The use of nature-based solutions (NbS) to address the risks posed by hydro-meteorological hazards have not yet become part of the mainstream policy response, and one of the main reasons cited for this, is the lack of evidence that they can effectively reduce disaster risk. This paper addresses this issue, by providing model-based evidence from five European case studies which demonstrate the effectiveness of five different NbS in reducing the magnitude of the hazard and thus risk, in present-day and possible future climates. In OAL-Austria, the hazard is a deep-seated landslide, and the NbS analysed is afforestation. Modelling results show that in today's climate and a landcover scenario of mature forest, a reduction in landslide velocity of 27.6% could be achieved. In OAL-Germany, the hazard is river flooding and the NbS analysed is managed grazing with removal of woody vegetation. Modelling results show that the NbS could potentially reduce maximum flood water depth in the near-future (2031-2060) and far-future (2070-2099), by 0.036m and 0.155m, respectively. In OAL-Greece, the hazard is river flooding, and the NbS is upscaled natural storage reservoirs. Modelling results show that in a possible future climate the upscaled NbS show most potential in reducing the total flooded area by up to 1.26 km2. In OAL-Ireland, the hazard is surface and river flooding, and the NbS is green roofs. Results from a modelled upscaling analysis under two different climate scenarios show that both maximum flood water depth, and total flooded area were able to be reduced. In OAL-UK, the hazard is shallow landslides, and the NbS is high-density planting of two different tree species. Modelling results under two different climate scenarios show that both tree species were able to improve slope stability, and that this increased over time as the NbS matured. The significance of these results is discussed within the context of the performance of the NbS over time, to different magnitude type events, impact with stakeholders in engendering wider support for the adoption of the NbS in the OALs, and the uncertainty in the modelling analyses.
This study aims to address the challenges associated with rockfall assessment and monitoring, focusing on the coastal cliffs of “Navagio Shipwreck Beach” in Zakynthos. A complete time-series analysis was conducted using state-of-the-art methodologies including a 2020 survey using unmanned aerial systems (UASs) and two subsequent surveys, incorporating terrestrial laser scanning (TLS) and UAS survey techniques in 2023. Achieving high precision and accuracy in georeferencing involving direct georeferencing, the utilization of pseudo ground control points (pGCPs), and integrating post-processing kinematics (PPK) with global navigation satellite system (GNSS) permanent stations’ RINEX data is necessary for co-registering the multitemporal models effectively. For the change detection analysis, UAS surveys were utilized, employing the multiscale model-to-model cloud comparison (M3C2) algorithm, while TLS data were used in a validation methodology due to their very high-resolution model. The synergy of these advanced technologies and methodologies offers a comprehensive understanding of rockfall dynamics, aiding in effective assessment and monitoring strategies for coastal cliffs prone to rockfall risk.
Museums are called to respond to contemporary challenges and contribute to the formation of more progressive societies. One of the major challenges of our time is climate change and sustainability, and museums could construct cocreated narratives around climate and implement targeted actions for the audiences through their sensorial and affective experiences. More specifically, Geology and Paleontology museums are repositories of knowledge on geoheritage and geoconservation, recognized for their scientific, pedagogical, cultural, and recreational values. The educational potential of geological and paleontological exhibits could be used in informal education activities regarding the climate emergency and the need for sustainability. Taking the above into consideration, this study focuses on both the creation and the evaluation of an educational program for the Natural History Museum of Arsakeio Campus in Psychicko. According to our findings, students really enjoyed their experience in the Museum, gained knowledge regarding mass extinctions driven by climate change, and suggested ways to tackle the current problems and promote our planet’s sustainability.
The pincer complexes [NiIIBr(CNC)]Br (4), [CrIIIBr3(CNC)] (5 a) and [CrIIIBr2.3Cl0.7(CNC)] (5 b), where CNC=3,3′-(pyridine-2,6-diyl)bis(1-mesityl-3,4,5,6-tetrahydropyrimidin-2-ylidene), were obtained from the novel ligand CNC, generated in situ from the precursor (CHNCH)Br2 and [NiIIBr2(PPh3)2] or from [CrII{N(SiMe3)2}2(THF)2] and (CHNCH)Br2 by aminolysis, respectively. The tetrahedrally distorted square planar (τ4≅0.30) geometry and the singlet ground state of Ni in 4 were attributed to steric constraints of the CNC backbone. Computational methods highlighted the dependence of the coordination geometry and the singlet-triplet energy difference on the size of the N-substituent of the tetrahydropyrimidine wingtips and contrasted it to the situation in 5-membered imidazolin-2-ylidene pincer analogues. The octahedral CrIII metal center in 5 a and 5 b is presumably formed after one electron oxidation from CH2Cl2. 4/MAO and 5 a/MAO were catalysts of moderate activity for the oligomerization and polymerization of ethylene, respectively. The analogous (CH^N^CH)Br2 precursor, where (CH^N^CH)=3,3′-(pyridine-2,6-diylbis(methylene))bis(1-mesityl-3,4,5,6-tetrahydropyrimidin-1-ium), was also prepared, however its coordination chemistry was not studied due to the inherent instability of the resulting free C^N^C ligand.
The aim of this study was to investigate whether an epistemological adequacy (knowledge of the Nature of Science, NOS) contributes to a better understanding and the acceptance of the Theory of Evolution by Natural Selection (ThENS). It was performed in two parts with the help of two questionnaires: 1. with students of Education, with a minimum familiarity to ThENS and NOS, before and after the application of a general biology course, and 2. with 200 Science Education teachers of various specialties who teach or have taught biology-related subjects. The education students showed some moderate levels of profi ciency regarding NOS that was improved statistically signifi cantly, even after a limited teaching intervention. An interesting founding was that, while their understanding of the ThENS was not very much improved by the course, it was found a positive correlation between their NOS familiarity and acceptance of evolution. As for the Science teachers, besides the above queries, some other variables were additionally investigated: E.g. to what extent, a better Epistemological Adequacy (knowledge of the Nature of Science) can infl uence their understanding and acceptance of the ThENS, or whether this affi liation could have been affected by their college or university instruction. The results showed a positive correlation between their epistemological adequacy and the acceptance and understanding of ThENS.
Savran D, Isaak J, Ayangeakaa AD, Beuschlein M, Finch SW, Gribble D, Gupta A, Hauf J, James XK, Janssens RVF, et al.NSR Query Results. Phys. Rev. C Phys Rev C. 2024;109:044604.
Linh BD, Corsi A, Gillibert A, Obertelli A, Doornenbal P, Barbieri C, Duguet T, Gomez-Ramos M, Holt JD, Hu BS, et al.NSR Query Results. Phys. Rev. C. 2024;109:034312.
Efstathiou M, Vasileiou P, Mertzimekis T, Zyriliou A, Karadimas A, Chalil A, Koseoglou P, Mărginean N, Mihai C, Costache C, et al.Nuclear lifetime measurements around Z= 50. HNPS Advances in Nuclear Physics. 2024;30:51–54.
OBJECTIVE: Nutritional guidelines for postmenopausal women differ. This study aimed to assess postmenopausal women's knowledge, beliefs, and practices regarding nutrition during menopause and their dietary habits. METHODS: This cross-sectional study was conducted in a menopause clinic, and data from 105 women were analyzed. A nutrition knowledge, attitudes, and perceptions (KAP) questionnaire was designed, structured, and piloted before implementation, based on the Hellenic dietary guidelines. International Physical Activity Questionnaire-Greek version, MedDietScore, and Menopause-specific Quality of Life questionnaires were administered. RESULTS: The mean ± SD age of the women was 56.9 ± 4.6 years. The mean ± SD KAP score was 12.2 ± 3.5. Those who lived in rural areas had lower KAP scores than those who lived in urban areas ( P = 0.004). Of all the women, 74.5{%} knew the Mediterranean diet pyramid, whereas 9.8{%} knew the Hellenic dietary guidelines. Women who had read the guidelines showed better knowledge of Mediterranean diet food groups (Pearson, 0.309; P = 0.039). Knowledge of dairy services was correlated with consumption of dairy products ( P = 0.002). Furthermore, 76.4{%} were willing to participate in nutrition education programs. The International Physical Activity Questionnaire score was positively correlated with years of smoking ( P = 0.002). Physical activity correlated with adherence to the Mediterranean diet ( P = 0.044). CONCLUSIONS: The majority of postmenopausal Greek women in this study were unaware of the Hellenic dietary guidelines. In general, women's knowledge of nutrition during menopause was moderate. Greek postmenopausal women are willing to participate in nutrition education programs, which should raise awareness of healthy lifestyles through nutrition, exercise, and smoking cessation.
Accurate modelling of air-sea processes is essential for reliable forecasts of Mediterranean tropical-like cyclones (also known as “Medicanes”). Medicanes occasionally develop in the Mediterranean causing extreme weather conditions with catastrophic potential due to excessive precipitation, windstorms, and coastal flooding. In this work, we investigate how the complexity of ocean-wave-atmosphere coupling and model initialization affect the simulated track and intensity of the Medicane Ianos (2020). Results indicate that the model's initial conditions and the cyclone's development stage are the main drivers of track position errors, while ocean and wave feedback have a significant impact on the intensity and evolution of the cyclone. Compared with an atmosphere-only simulation, an atmosphere-ocean coupled system reproduces the cyclone's SST cooling effect (up to 3.7 °C), in agreement also with the satellite observations thus, reducing the cyclone intensity, as estimated by the minimum MSLP, the 10-m wind speed and the surface enthalpy flux. Adding a wave model to the coupled system, further increases the magnitude of ocean cooling (by about 1.2 °C), due to increased sea surface roughness leading to increased wind stress and enhanced upper ocean mixing. Overall, surface waves are shown to have competing effects on cyclone intensity i.e., negative feedback via increasing the surface momentum flux and positive feedback via increasing the enthalpy flux, the latter being more sensitive to surface roughness rather than to SST modifications brought by the wave coupled system. The turbulent air-sea fluxes under high winds, appear to be very sensitive to sea-state patterns resolved by the coupled models, highlighting the need to improve forecasting systems for extreme weather events in the Mediterranean.
Accurate modelling of air-sea processes is essential for reliable forecasts of Mediterranean tropical-like cyclones (also known as “Medicanes”). Medicanes occasionally develop in the Mediterranean causing extreme weather conditions with catastrophic potential due to excessive precipitation, windstorms, and coastal flooding. In this work, we investigate how the complexity of ocean-wave-atmosphere coupling and model initialization affect the simulated track and intensity of the Medicane Ianos (2020). Results indicate that the model's initial conditions and the cyclone's development stage are the main drivers of track position errors, while ocean and wave feedback have a significant impact on the intensity and evolution of the cyclone. Compared with an atmosphere-only simulation, an atmosphere-ocean coupled system reproduces the cyclone's SST cooling effect (up to 3.7 °C), in agreement also with the satellite observations thus, reducing the cyclone intensity, as estimated by the minimum MSLP, the 10-m wind speed and the surface enthalpy flux. Adding a wave model to the coupled system, further increases the magnitude of ocean cooling (by about 1.2 °C), due to increased sea surface roughness leading to increased wind stress and enhanced upper ocean mixing. Overall, surface waves are shown to have competing effects on cyclone intensity i.e., negative feedback via increasing the surface momentum flux and positive feedback via increasing the enthalpy flux, the latter being more sensitive to surface roughness rather than to SST modifications brought by the wave coupled system. The turbulent air-sea fluxes under high winds, appear to be very sensitive to sea-state patterns resolved by the coupled models, highlighting the need to improve forecasting systems for extreme weather events in the Mediterranean.
Natural products are attractive components to tailor environmentally friendly advanced new materials. We present surface-confined metallosupramolecular engineering of coordination polymers using natural dyes as molecular building blocks: indigo and the related Tyrian purple. Both building blocks yield identical, well-defined coordination polymers composed of (1 dehydroindigo : 1 Fe) repeat units on two different silver single crystal surfaces. These polymers are characterized atomically by submolecular resolution scanning tunnelling microscopy, bond-resolving atomic force microscopy and X-ray photoelectron spectroscopy. On Ag(100) and on Ag(111), the trans configuration of dehydroindigo results in N,O-chelation in the polymer chains. On the more inert Ag(111) surface, the molecules additionally undergo thermally induced isomerization from the trans to the cis configuration and afford N,N- plus O,O-chelation. Density functional theory calculations confirm that the coordination polymers of the cis-isomers on Ag(111) and of the trans-isomers on Ag(100) are energetically favoured. Our results demonstrate post-synthetic linker isomerization in interfacial metal-organic nanosystems.
In this paper we study periodicity phenomena for modular extensions between Weyl modules and between Weyl and simple modules of the general linear group that are associated to adding a power of the characteristic to the first parts of the involved partitions.
PURPOSE: Variants in the GNB1 gene, which encodes for the beta-1 subunit of G proteins, have been associated with intellectual development disorder (OMIM: 616973), characterized by developmental delay, infantile hypotonia, seizures, and psychiatric problems. GNB1 variants may also cause a multisystem disorder, with symptoms such as hearing and vision impairment, gastrointestinal disorders, genitourinary abnormalities, and growth delay. CASE PRESENTATIONS: We present two pediatric patients with two novel GNB1 variants. The first patient is a 12-year old Caucasian European female with a history of neonatal hypotonia, feeding difficulties, and failure to thrive for the first 2 years of life. Subsequently, she developed grade 3 obesity, hyperphagia, and autoimmune thyroiditis. Whole Exome Sequencing (WES) revealed a novel likely pathogenic variant in the GNB1 gene (NM{\_}002074.5:c.93{\_}94del, p.Gln32AspfsTer46), which is predicted to result in a loss or disruption of normal protein function through nonsense-mediated decay (NMD) or protein truncation. The second patient is a 2-year old Roma female with severe failure to thrive during infancy, congenital hypothyroidism, and transient hyperoxaluria. No developmental delay was identified. Genetic testing excluded primary hyperoxaluria and WES revealed to be a novel likely pathogenic variant {\{}NM{\_}002074.5:c.183G {\textgreater} T (NP{\_}002065.1:p.Met61Ile), which is predicted to have a damaging effect on the gene or gene product. CONCLUSION: We present two rare pediatric cases with novel GNB1 variants which highlight the phenotypic variability associated with disrupted GNB1 expression. GNB1 may serve as a candidate gene for severe early onset obesity, hyperphagia, neurodevelopmental delay, and other metabolic and endocrine disorders.}
BACKGROUND: Pulmonary complications are the most common cause of death after surgery. This study aimed to derive and externally validate a novel prognostic model that can be used before elective surgery to estimate the risk of postoperative pulmonary complications and to support resource allocation and prioritisation during pandemic recovery.
METHODS: Data from an international, prospective cohort study were used to develop a novel prognostic risk model for pulmonary complications after elective surgery in adult patients (aged ≥18 years) across all operation and disease types. The primary outcome measure was postoperative pulmonary complications at 30 days after surgery, which was a composite of pneumonia, acute respiratory distress syndrome, and unexpected mechanical ventilation. Model development with candidate predictor variables was done in the GlobalSurg-CovidSurg Week dataset (global; October, 2020). Two structured machine learning techniques were explored (XGBoost and the least absolute shrinkage and selection operator [LASSO]), and the model with the best performance (GSU-Pulmonary Score) underwent internal validation using bootstrap resampling. The discrimination and calibration of the score were externally validated in two further prospective cohorts: CovidSurg-Cancer (worldwide; February to August, 2020, during the COVID-19 pandemic) and RECON (UK and Australasia; January to October, 2019, before the COVID-19 pandemic). The model was deployed as an online web application. The GlobalSurg-CovidSurg Week and CovidSurg-Cancer studies were registered with ClinicalTrials.gov, NCT04509986 and NCT04384926.
FINDINGS: Prognostic models were developed from 13 candidate predictor variables in data from 86 231 patients (1158 hospitals in 114 countries). External validation included 30 492 patients from CovidSurg-Cancer (726 hospitals in 75 countries) and 6789 from RECON (150 hospitals in three countries). The overall rates of pulmonary complications were 2·0% in derivation data, and 3·9% (CovidSurg-Cancer) and 4·7% (RECON) in the validation datasets. Penalised regression using LASSO had similar discrimination to XGBoost (area under the receiver operating curve [AUROC] 0·786, 95% CI 0·774-0·798 vs 0·785, 0·772-0·797), was more explainable, and required fewer covariables. The final GSU-Pulmonary Score included ten predictor variables and showed good discrimination and calibration upon internal validation (AUROC 0·773, 95% CI 0·751-0·795; Brier score 0·020, calibration in the large [CITL] 0·034, slope 0·954). The model performance was acceptable on external validation in CovidSurg-Cancer (AUROC 0·746, 95% CI 0·733-0·760; Brier score 0·036, CITL 0·109, slope 1·056), but with some miscalibration in RECON data (AUROC 0·716, 95% CI 0·689-0·744; Brier score 0·045, CITL 1·040, slope 1·009).
INTERPRETATION: This novel prognostic risk score uses simple predictor variables available at the time of a decision for elective surgery that can accurately stratify patients' risk of postoperative pulmonary complications, including during SARS-CoV-2 outbreaks. It could inform surgical consent, resource allocation, and hospital-level prioritisation as elective surgery is upscaled to address global backlogs.
FUNDING: National Institute for Health Research.
This paper discusses certain aspects of the dominant cultural heritage discourse in Greece, and their effects on the construction, preservation, and diffusion of public memory; although my case studies will not be archaeological as such, I will be discussing the materialities political power is imbued with, and the ways in which it regenerates itself at their expense (a process in which Greek archaeology often interferes). Focusing on what we generally call “alien monuments,” that is, monuments that do not form part of the hegemonic culture, the paper discusses minority legacies, as they strive to rescue themselves from centrally waged wars on memory, and oblivion.
INTRODUCTION: Tanzania has a high adolescent birth rate and many sexually active adolescents do not have access to effective contraception. Teenage pregnancy is considered a high-risk pregnancy. Furthermore, it leads to social inequalities for both mother and offspring. METHODS: We conducted semistructured interviews with 12 adolescent mothers during their stay in the postnatal ward of the maternity department of a tertiary hospital in Zanzibar. The study took place between November and December 2022. Data were then analyzed qualitatively. RESULTS: The main theme that emerged from the interview data was that pregnancy seemed to affect the lives of young girls in a negative way. The majority of pregnancies were unplanned, and the girls reported low family planning uptake. Another recurring theme was that girls had many οbstacles in their education prior to pregnancy, which left them uncertain about their future. Finally, despite the advice of local doctors, the majority of the girls received minimal prenatal care, mostly because they did not regard obstetric care to be a priority. CONCLUSIONS: Adolescent pregnancy remains an important public health issue in Tanzania, despite significant measures by authorities to reduce it. Educational changes and professional opportunities as well as family planning services may enable young girls to achieve professional and personal goals while delaying motherhood into adulthood.
The present paper focuses on the recall of childhood experiences of adults who had at least one parent misusing alcohol and/or drugs. The study aims to gain an in-depth understanding of the recall of these experiences in adulthood and their effect on relationships with significant others. Twelve (12) adults, who had experienced as children in their family’s drug and alcohol misuse were interviewed and their interviews were analyzed using thematic analysis. The findings of the qualitative study suggest that adults recall in their childhood the reversal of family roles and traumas that seem to affect their current relationships. The research findings indicate the necessity of supporting early enough children who grow up in families where alcohol and drug misuse are part of daily life and to create a therapeutic alliance in adult life in order to advance in their relationship with self and others.
Context. Relativistic shocks are present in all high-energy astrophysical processes involving relativistic plasma outflows interacting with their ambient medium. While they are well understood in the context of relativistic hydrodynamics and ideal magnetohydrodynamics (MHD), there is a limited understanding of the properties related to their propagation in media characterized by finite electrical conductivity. Aims: This work presents a systematic method for the derivation and solution of the jump conditions for relativistic shocks propagating in MHD media with finite electrical conductivity. This method is applied to the numerical solution of the Riemann problem and the determination of the conditions inside the blastwave that is formed when ultrarelativistic magnetized ejecta interact with the circumburst medium during a gamma-ray burst. Methods: We derived the covariant relations expressing the jump conditions in a frame-independent manner. The resulting algebraic equations expressing the Rankine-Hugoniot conditions in the propagation medium's frame were then solved numerically. A variable adiabatic index equation of state was used in order to obtain a realistic description of the post-shock fluid's thermodynamics. This method was then employed for the solution of the Riemann problem for the case of a forward and a reverse shock, both of which form during the interaction of a gamma-ray burst ejecta with the circumburst medium. This allowed us to determine the kinematics of the resulting blastwave and the dynamical conditions in its interior. Results: Our solutions clearly depict the impact of the plasma's electrical conductivity in the properties of the post-shock medium. Two characteristic regimes are identified with respect to the value of a dimensionless parameter that has a linear dependence on the conductivity. For small values of this parameter, the shock affects only the hydrodynamic properties of the propagation medium and leaves its electromagnetic field unaffected. No current layer forms in the shock front; thus, we refer to this as the current-free regime. For large values of this parameter, the ideal MHD regime has been retrieved. We also show that the assumption of a finite electrical conductivity can lead to higher efficiencies in the conversion of the ejecta energy into thermal energy of the blastwave through the reverse shock. The theory developed in this work can be applied to the construction of Riemann solvers for resistive relativistic MHD (RR4MHD).
The carnation Dianthus fruticosus L. ssp. fruticosus (Caryophyllaceae) is a range-restricted perennial, endemic plant that grows on cliffs, rocks, ravines, terraces, and boulders on Serifos Island in the Cyclades in the Aegean archipelago (Greece), possessing an impressive, aesthetic blossoming during the dry season. This indigenous carnation of Serifos has attracted the interest of naturalists andscientists. Specimens of this subspecific taxon from the island of Serifos (Greece) were collected during botanical explorations in preindustrial times by the French naturalist Joseph Pitton de Tournefort (1702) and in the late eighteenth century by the English Professor of Botany at the University of Oxford John Sibthorp (1787). Those specimens, documented in relevant publications and labelled with different names (i.e., Caryophyllus Graecus arboreus and Caryophyllus arboreus Seriphius in the early eighteenth century and Dianthus fruticosus in the early nineteenth century), are related to aspects of vegetation history, linking the past to the present and (most probably) to the future. Today, a thorough understanding of the in situ development and functionality of this endemic carnation is still required, as is a framework of its sustainability and management in small-scale insular habitats. The timeless perception of the emblematic wild carnation Dianthus fruticosus ssp. fruticosus, which is still growing on inland and coastal sites of Serifos and neighboring islands in the Cyclades (Greece), is also a reminder that a native plant is often a repository to which local communities may look when crafting their identity.
This manuscript presents a multidisciplinary study that proposes a methodology for delineating and categorizing vulnerability at rockfall risk areas to avoid human injuries and infrastructure damage caused by rockfalls. The presented workflow includes (i) classical geological mapping, (ii) the interpretation of high-resolution satellite data for observing the spatial distribution of fallen boulders, (iii) analytical hierarchy processing of spatial information within a Geographical Information System (GIS) platform, (iv) close-range remote sensing campaigns with Unmanned Aerial Systems (UASs), and (v) integrated simulation of rockfall events. This methodology was applied to Kalymnos Island, which belongs to the Dodecanese Islands complex of the southeastern Aegean Sea in Greece. It is characterized by unique geomorphological features, including extensive vertical limestone cliffs that span the island. These cliffs make it one of the world’s most densely concentrated areas for sport climbing. The results highlighted the areas that the local authorities need to focus on and suggested measures for increasing the safety of climbers and infrastructure.
This study investigated the influence of language – first language (L1)versus second language (L2) – on the experience and the expression ofthe emotion of guilt. Fifty-two Greek – Spanish bilinguals read twomoral scenarios that induced guilt in their L2 (Spanish) and rated theintensity with which they felt a series of emotions (moral scenario task).Then they were asked to recall and write about a real-life event thatmade them feel guilty in their L2 (autobiographical memory task). Amonth later they performed the same tasks in their L1. Content analysisand emotional vocabulary analysis were conducted to examine crosslinguisticdifferences in the expression of guilt. Overall, these bilingualsexperienced higher levels of guilt and regret when they read the moralscenarios in their L1 Greek. They also used a greater number of emotionwords in their autobiographical memories in L1. However, theyappeared to be more willing to talk about sensitive topics (e.g.infidelity, homosexuality, and death) in their L2. These findings haveimplications for both psychotherapy and L2 instruction.
The purpose of this research is to create a typology of the long-distance running community of Greece. The sample consisted of 3228 participants/runners in the "Athens Marathon. The Authentic". The variables used for the segmentation included the demographic, social, attitudinal, and behavioral characteristics of the individuals participating in running as a leisure time physical activity. A cluster analysis was implemented using Python K-Mode by creating a code and using the Elbow method because all the variables were categorical. The analysis yields five (5) different clusters, with some similarities but discernible differences, which distinguish each one of the clusters, making them unique. According to the recorded differences, each one of the clusters was assigned a name. The first cluster was named Leisure Health-Oriented Joggers, the second cluster Older Competitive Marathon Runners, the third Health Oriented Experienced Marathon Runners, the fourth Lonely Marathon Runners, and the fifth Sports Oriented Social Marathon Runners. This is the first-ever presentation of a typology of the Greek running community. Moreover, such a typology could benefit the private and public sectors. Specifically, the segmentation of the running community could influence the sport industry in regard to services, products or merchandise as well as entrepreneurial initiatives. By focusing on the characteristics of each distinctive cluster, the public sector could use this as a guide in planning and implementing new physical activity policies, projects and programs.
Keywords: Marathon, Running movement, Physical Activity, Segmentation, Habits, Attitudes, Sport industry, Market segmentation, Gender gap
Organometallic complexes of the formula [Ru(N^N)(p-cymene)Cl][X] (N^N = bidentate polypyridyl ligands, p-cymene = 1-methyl-4-(1-methylethyl)-benzene, X = counter anion), are currently studied as possible candidates for the potential treatment of cancer. Searching for new organometallic compounds with good to moderate cytotoxic activities, a series of mononuclear water-soluble ruthenium(II)–arene complexes incorporating substituted pyridine–quinoline ligands, with pending -CH2OH, -CO2H and -CO2Me groups in the 4-position of quinoline ring, were synthesized, for the first time, to study their possible effect to modulate the activity of the ruthenium p-cymene complexes. These include the [Ru(η6-p-cymene)(pqhyme)Cl][X] (X = Cl− (1-Cl), PF6− (1-PF6), pqhyme = 4-hydroxymethyl-2-(pyridin-2-yl)quinoline), [Ru(η6-p-cymene)(pqca)Cl][Cl] ((2-Cl), pqca = 4-carboxy-2-(pyridin-2-yl)quinoline), and [Ru(η6-p-cymene)(pqcame)Cl][X] (X = Cl− (3-Cl), PF6− (3-PF6), pqcame = 4-carboxymethyl-2-(pyridin-2-yl)quinoline) complexes, respectively. Identification of the complexes was based on multinuclear NMR and ATR-IR spectroscopic methods, elemental analysis, conductivity measurements, UV–Vis spectroscopic, and ESI-HRMS techniques. The solid-state structures of 1-PF6 and 3-PF6 have been elucidated by single-crystal X-ray diffraction revealing a three-legged piano stool geometry. This is the first time that the in vitro cytotoxic activities of these complexes are studied. These were conducted in HEK293T (human embryonic kidney cells) and HeLa cells (cervical cancer cells) via the MTT assay. The results show poor in vitro anticancer activities for the HeLa cancer cell lines and 3-Cl proved to be the most potent (IC50 > 80 μΜ). In both cell lines, the cytotoxicity of the ligand precursor pqhyme is significantly higher than that of cisplatin.
Organometallic ruthenium complexes with p-cymene = 1-methyl-4-(1-methylethyl)-benzene and N^N = bidentate polypyridyl ligands constitute interesting candidates with biological and catalytic properties. Towards this aim, we have synthesized four ruthenium(II)–arene complexes of the type [Ru(η6-p-cymene)(N^N)Cl][X] (N^N = Br-Qpy = 6-bromo-4-phenyl-2-pyridin-2-yl-quinoline, X = Cl− (1a); PF6− (1b); N^N = OH-Ph-Qpy = 4-(4-phenyl-2-(pyridin-2-yl)quinolin-6-yl)phenol, X = Cl− (2a); PF6− (2b)). This is the first report of ruthenium(II) p-cymene complexes incorporating substituted pyridine–quinoline ligands, with –Br and –C6H4OH groups in the 6-position of quinoline. We also refer to the cytotoxicity of the ligands and their possible effect of modulating the activity of the ruthenium(II) complexes. These were characterized by a combination of spectroscopic methods (ATR-IR, UV–Vis, multinuclear NMR), elemental analysis, and conductivity measurements. The solid-state structure of 2b, determined by single-crystal X-ray diffraction, reveals a three-legged piano-stool geometry. The in vitro cytotoxic activities of the new complexes were evaluated in HEK293T (human embryonic kidney cells) and in HeLa cells (cervical cancer cells), via the MTT assay. Poor in vitro anticancer activities were observed for the HeLa cancer cell line, with 2a being the most potent (IC50 = 75 μΜ). The cytotoxicity of Br-Qpy in HEK293T is comparable to that of cisplatin. Both complexes 1a and 1b successfully catalyze the transfer hydrogenation of benzophenone to benzhydrol by 2-propanol at 82 °C. The catalytic performance of 1a in the ratio of S:Cat:B = 400:1:40 (S = substrate, Cat = catalyst, B = base = KOiPr) leads to a conversion of 94%, within 3 h of reaction. Presumably, catalytic transformation takes place via ruthenium(II) hydride species being the active catalyst.
Background: School health education (SHE) serves as a primary pedagogical aspect of public health. This study aims to explore the curricula of preservice schoolteachers, examining whether graduate courses in Greek universities include SHE, how it is structured, and whether critical pedagogy principles are integrated. Methods: A corpus of n = 21 documents was compiled, encompassing all educational departments in Greek higher education, including Departments of Early Childhood Education and Care (n = 3), Departments of Preschool Education (n = 9), and Departments of Primary Education (n = 9). Results: Content analysis revealed the presence of SHE in 11 out of 21 educational departments. Thematic analysis uncovered significant variability in the curricula, with greater emphasis placed on health-related topics rather than the methodologies and values of SHE. Critical pedagogy principles were not explicitly evident in the curricula, while a persistent biomedical orientation left little room for the development of concepts related to social justice. Conclusions: This study represents the first of its kind in Greece and among the few internationally to examine preservice training for schoolteachers in SHE. The findings underscore the need for revisions to align with the key lessons learned from the major public health crisis of the COVID-19 pandemic. It is imperative to acknowledge that vulnerabilities have been exacerbated, and inequalities widened, necessitating a reassessment of current approaches to health education within teacher training programs.
Blazars—a subclass of active galaxies—are intrinsically time-variable broadband sources of electromagnetic radiation. In this contribution, we explored relativistic proton (hadronic) signatures in the time domain blazar emission and searched for those parameter combinations that unveil their presence during flaring epochs. We generated time series for key model parameters, like magnetic field strength and the power-law index of radiating particles, which were motivated from a simulated time series with statistical properties describing the observed GeV gamma-ray flux. We chose the TeV blazar Mrk 501 as our test case, as it had been the study ground for extensive investigations during individual flaring events. Using the code LeHaMoC, we computed the electromagnetic and neutrino emissions for a period of several years that contained several flares of interest. We show that for both of those particle distributions the power-law index variations that were tied to moderate changes in the magnetic field strength of the emitting region might naturally lead to hard X-ray flares with very-high-energy γ-ray counterparts. We found spectral differences measurable by the Cherenkov Telescope Array Observatory at sub-TeV energies, and we computed the neutrino fluence over 14.5 years. The latter predicted ∼0.2 muon and anti-muon neutrinos, consistent with the non-detection of high-energy neutrinos from Mrk 501.
Neuropsychiatric disorders, which are associated with stress hormone dysregulation, occur at different rates in men and women. Moreover, nowadays, preclinical and clinical evidence demonstrates that sex and gender can lead to differences in stress responses that predispose males and females to different expressions of similar pathologies. In this curated review, we focus on what is known about sex differences in classic mechanisms of stress response, such as glucocorticoid hormones and corticotrophin-releasing factor (CRF), which are components of the hypothalamicpituitary- adrenal (HPA) axis. Then, we present sex differences in neurotransmitter levels, such as serotonin, dopamine, glutamate and GABA, as well as indices of neurodegeneration, such as amyloid β and Tau. Gonadal hormone effects, such as estrogens and testosterone, are also discussed throughout the review. We also review in detail preclinical data investigating sex differences caused by recentlyrecognized regulators of stress and disease, such as the immune system, genetic and epigenetic mechanisms, as well neurosteroids. Finally, we discuss how understanding sex differences in stress responses, as well as in pharmacology, can be leveraged into novel, more efficacious therapeutics for all. Based on the supporting evidence, it is obvious that incorporating sex as a biological variable into preclinical research is imperative for the understanding and treatment of stress-related neuropsychiatric disorders, such as depression, anxiety and Alzheimer's disease.
The paper explores the potential of sound to repoliticize theatre and performance. By examining the activity and dramaturgical practices of the multimedia art collective Medea Electronique (Greece), it highlights contradictions of contemporary art, particularly the continuous transition from ‘everything is political’ to ‘no, not everything is political’ and vice versa. From a post-Brechtian perspective, the political function of art lies in preserving the diverse sensibilities at the core of art’s autonomy. This entails avoiding that art be reduced to a post-political gesture or aligning it too closely with everyday aestheticized experiences.
François-René de Chateaubriand occupe une place particulière dans la mémoire collective de la Grèce moderne. Il est inscrit dans les lettres grecques modernes au double titre de philhellène et d’homme de lettres, aux côtés d’autres écrivains et philhellènes européens tels que Byron et Victor Hugo ou encore Béranger. À sa mort, en juillet 1848, les journaux grecs saluent unanimement un fidèle ami de la Grèce. Mais dans quelle mesure son œuvre littéraire était-elle connue du public grec ? Quelles œuvres étaient traduites et quelle en fut leur réception ? La présente étude tente un premier recensement des traductions grecques de Chateaubriand au XIXe siècle et une périodisation de la présence de son œuvre en Grèce. Si dans un premier temps les lecteurs de Chateaubriand appartiennent à une élite intellectuelle francophone susceptible de pouvoir le lire dans l’original, le cercle des lecteurs s’élargit progressivement grâce notamment à des traductions intégrales mais aussi grâce à des traductions partielles insérées dans les revues littéraires du XIXe siècle.
Remotely sensed data play a crucial role in monitoring the El Niño/La Niña Southern Oscillation (ENSO), which is an oceanic-atmospheric phenomenon occurring quasi-periodically with several impacts worldwide, such as specific biological and global climate responses. Since 1980, Earth has witnessed three strong ENSO events (1982–1983, 1997–1998, 2015–2016). In September 2022, La Niña entered its third year and was unlikely to continue through 2024. Instead, since 2022, forecasts have pointed to a transition from La Niña to a Neutral phase in the summer or late 2023. The onset of El Niño occurred around April 2023, and it is anticipated by sophisticated models to be a strong event through the Northern Hemisphere winter (December 2023–February 2024). The aim of this study is to demonstrate the ability of the combination of two new methods to improve the accuracy of the above claim because El Niño apart from climate anomalies, significantly impacts Earth’s ecosystems and human societies, regulating the spread of diseases by insects (e.g., malaria and dengue fever), and influencing nutrients, phytoplankton biomass, and primary productivity. This is done by exploring first the previous major El Niño events in the period January 1876–July 2023. Our calculations show that the ongoing 2023–2024 El Niño will not be the strongest.
Active tuning of the scattering of particles and metasurfaces is a highly sought-after property for a host of electromagnetic and photonic applications, but it normally requires challenging-to-control tunable (reconfigurable) or active (gain) media. Here, we introduce the concepts of anisotropic virtual gain and oblique Kerker effect, where a completely lossy anisotropic medium behaves exactly as its anisotropic
gain counterpart upon excitation by a synthetic complex-frequency wave. The strategy allows one to largely tune the magnitude and angle of a particle’s scattering simply by changing the shape (envelope) of the incoming radiation, rather than by an involved medium-tuning mechanism. The so-attained anisotropic virtual gain enables directional super-scattering at an oblique direction with fine-management of the scattering angle. Our study is based on analytical techniques that allow multipolar decomposition of the scattered field in agreement with full-wave simulations, and lays the foundations for a light management method.
Metasurfaces are capable of fully reshaping the wavefronts of incident beams in desiredmanners.However,therequirementforexternallightexcitationand the resonant nature of their meta-atoms, make challenging their on-chip integration. Here, we introduce the conceptanddesignofafreshclassof metasurfaces, driven by unidirectional guided waves, capable of arbitrary wavefront control based on the uniquedispersion properties of unidirectional guided waves rather than resonant meta-atoms. Upon experimentally demonstrating the feasibility of our designs in the microwave regime, we numerically validate the introduced principle through the design of several microwave meta-devices using metal-air-gyromagnetic unidirectional surface magneto-plasmons, agilely converting unidirectional guided modes into the wavefrontsof3DBesselbeams,focusedwaves,andcontrollablevortexbeams. We, further, numerically demonstrate sub-diffraction focusing, which is beyond the capability of conventional metasurfaces. Our unfamiliar yet prac tical designs may enable full, broadband manipulation of electromagnetic waves on deep subwavelength scales.
In the past two decades, index-near-zero (INZ) modes and materials, with their spatial phase invariance and super coupling, gained increasing attention for applications in all-optical/quantum computing and communication. However, the modulation of INZ modes is typically complex and discontinuous, often achieved through intricate experimental methods, thereby hindering their widespread application. Here, we propose two deep-subwavelength magneto-optical one-way waveguides and discover three broadband tunable INZ modes, exhibiting predict able behavior dependent on the external magnetic field (EMF). By utilizing these INZ modes, we design broadband tunable all-optical phase modulators through straightforward EMF control. The tunable and predictable nature of INZ modes, combined with deep-subwavelength phase modulators, may advance miniaturized all-optical communication and computation.
The inevitable feedback between the environmental and energy crisis within the next decades can probably trigger and/or promote a global imbalance in both financial and public health terms. To handle this difficult situation, in the last decades, many different classes of materials have been recruited to assist in the management, production, and storage of so-called clean energy. Probably, ferromagnets, superconductors and ferroelectric/piezoelectric materials stand at the frontline of applications that relate to clean energy. For instance, ferromagnets are usually employed in wind turbines, superconductors are commonly used in storage facilities and ferroelectric/piezoelectric materials are employed for the harvesting of stray energy from the ambient environment. In this work, we focus on the wide family of ferroelectric/piezoelectric materials, reviewing their physical properties in close connection to their application in the field of clean energy. Among other compounds, we focus on the archetypal compound Pb(Zr,Ti)O3 (or PZT), which is well studied and thus preferred for its reliable performance in applications. Also, we pay special attention to the advanced ferroelectric relaxor compound (1−x)Pb(Mg1/3Nb2/3)O3−xPbTiO3 (or PMN-xPT) due to its superior performance. The inhomogeneous composition that many kinds of such materials exhibit at the so-called morphotropic phase boundary is reviewed in connection to possible advantages that it may bring when applications are considered.
We aim to identify the key drivers of capital depletion under the adverse scenario by reverse engineering the EU-wide stress tests. Our sample consists of the banks that participated in the 2016, 2018 and 2021 EU-wide stress tests. We use three separate sets of variables, namely the bank-specific indicators, the macroeconomic parameters, and the banks’ exposures per loan portfolio. The results demonstrate that banks that are more profitable, more efficient, smaller, more exposed to corporate clients, less exposed to governments and having booked more impairments beforehand experience lower capital depletion under the adverse scenario. In addition, high rates of inflation imply more severe capital reductions, while high GDP leads to mild capital depletion. The asset mix on banks' balance sheets significantly affects the impact of stress test under the adverse scenario. Results are robust to alternative econometric approaches and provide important implications for both supervisors and banks.
Nanoparticle formation by Spark Discharge Aerosol Generation offers low-cost fabrication of nanoparticles, without the use of chemicals or vacuum. It produces aerosol particles of a few nanometers in size with high purity. In this work, copper-based - CuO (tenorite) and Cu- nanoparticles are produced, characterized and used to modify face mask air filters, achieving the introduction of antibacterial and antiviral properties. A range of characterization techniques have been employed, down to the atomic level. The majority of the particles are CuO (of a few nanometers in size that agglomerate to form aggregates), the remainder being a small number of larger Cu particles. The particles were deposited on various substrates, mainly fiber filters in order to study them and use them as biocidal agents. On face masks, their antibacterial activity against Escherichia coli (E.coli) results in a 100% decrease in bacteria cell viability. Their antiviral activity on face masks results in a 90% reduction of the Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2) viability, 15 minutes post the application of the virus stock solution. This highlights the effectiveness of this approach, its simplicity, its low cost and its excellent environmental credentials.
Context. A correlation has been reported between the arrival directions of high-energy IceCube events and γ-ray blazars classified as intermediate- and high-synchrotron-peaked BL Lacs. Subsequent studies have investigated the optical properties of these sources, compiled and analyzed public multiwavelength data, and constrained their individual neutrino emission based on public IceCube point-source data. Aims. We provide a theoretical interpretation of public multiwavelength and neutrino point source data for the 32 BL Lac objects in the sample previously associated with an IceCube alert event. We combined the individual source results to draw conclusions regarding the multimesssenger properties of the sample and the required power in relativistic protons. Methods. We performed particle interaction modeling using open-source numerical simulation software. We constrained the model parameters using a novel and unique approach that simultaneously describes the host galaxy contribution, the observed synchrotron peak properties, the average multiwavelength fluxes, and, where possible, the IceCube point source constraints. Results. We show that a single-zone leptohadronic model can describe the multiwavelength broadband fluxes from all 32 IceCube candidates. In some cases, the model suggests that hadronic emission may contribute a considerable fraction of the γ-ray flux. The required power in relativistic protons ranges from a few percent to a factor of ten of the Eddington luminosity, which is energetically less demanding compared to other leptohadronic blazar models in recent literature. The model can describe the 68% confidence level IceCube flux for a large fraction of the masquerading BL Lacs in the sample, including TXS 0506+056; whereas, for true BL Lacs, the model predicts a low neutrino flux in the IceCube sensitivity range. Physically, this distinction is due to the presence of photons from broad line emission in masquerading BL Lacs, which increase the efficiency of hadronic interactions. The predicted neutrino flux peaks between a few petaelectronvolt and 100 PeV and scales positively with the flux in the gigaelectronvolt, megaelectronvolt, X-ray, and optical bands. Based on these results, we provide a list of the brightest neutrino emitters, which can be used for future searches targeting the 10–100 PeV regime.
Enciu M, Obertelli A, Doornenbal P, Heinz M, Miyagi T, Nowacki F, Ogata K, Poves A, Schwenk A, Yoshida K, et al.Spectroscopy of K 52. Physical Review C. 2024;110:064301.
Consider the general linear group $G=GL_{n}(K)$ defined over an infinite field $K$ of positive characteristic $p$. We denote by $\Delta(\lambda)$ the Weyl module of $G$ which corresponds to a partition $\lambda$. Let $\lambda, \mu$ be partitions of $r$ and let $\gamma$ be partition with all parts divisible by $p$. In the first main result of this paper, we find sufficient conditions on $\lambda, \mu and \gamma$ so that $Hom_G(\Delta(\lambda),\Delta(\mu)) \simeq Hom_G(\Delta(\lambda +\gamma),\Delta(\mu +\gamma))$, thus providing an answer to a question of D. Hemmer. As corollaries we obtain stability and periodicity results for homomorphism spaces. In the second main result we find related sufficient conditions on $\lambda, \mu$ and $p$ so that $Hom_G(\Delta(\lambda),\Delta(\mu))$ is nonzero. An explicit map is provided that corresponds to the sum of all semistandard tableaux of shape $\mu$ and weight $\lambda$.
Static waste heat recovery, by means of thermoelectric generator (TEG) modules, constitutes a fast-growing energy harvesting technology on the way towards greener transportation. Many commercial solutions are already available for small internal combustion engine (ICE) vehicles, whereas further development and cost reductions of TEG devices expand their applicability at higher-power transportation means (i.e., ships and aircrafts). In this light, the integration of waste heat recovery based on TEG modules in a shipboard distribution network is studied in this work. Several voltage step-up techniques are considered, whereas the most suitable ones are assessed via the LTspice simulation platform. The design procedure of the selected LLC resonant converter is presented and analyzed in detail. Furthermore, a flexible control strategy is proposed, capable of either output voltage regulation (constant voltage) or maximum power point tracking (MPPT), according to the application demands. Finally, both simulations and experiments (on a suitable laboratory testbench) are performed. The obtained measurements indicate the high efficiency that can be achieved with the LLC converter for a wide operating area as well as the functionality and adequate performance of the control scheme in both operating conditions.
Teachers face many issues when trying to integrate digital resources (DR) into mathematics classes. This article applies an identity-based perspective to understand teachers’ roles in the practices that evolve in such classes. We focus on Victor, a Greek mathematics teacher, who, when viewed from levels beyond the classroom, experienced to become a reform-oriented teacher and a designer of DR. We explore how these experiences of professional identity shapes and is shaped by his work with DR at the classroom level. We show how Victor’s identity changed from ‘being a Mathematics teacher who struggles with inquiry-based teaching’ to ‘becoming a mathematics Teacher who uses DR to support inquiry-based learning’ and outline what fuelled these changes. Our results suggest the importance of connecting an identity perspective to classroom interactions and mathematics.
Health literacy is a significant element of education and is inextricably linked to children’s and adolescents’ growth and prosperity. It is critical to monitor students’ health literacy on a nationwide scale and identify the factors that influence it in order to create policies that advance it. The purpose of this study was to determine the health literacy level of Greek secondary school students and to correlate it with possible determinants such as personal and family characteristics, social support and personal and/or family illness experiences. A representative sample of 2749 seventh-, ninth-, and tenth-grade students was involved. Results showed that a higher motivation to learn about health topics and having positive social interactions and support were strongly associated with a higher level of health literacy. Gender, high academic achievement, absence of learning disabilities, gender, preference for biology and informatics and primary source of health information were also found to influence the skills’ level. In order to enhance health literacy, the Greek educational system should take measures to include health literacy skills development goals in their curricula.
Oxidative stress refers to the overproduction of reactive oxygen species and is often associated with numerous pathological conditions. Superoxide dismutase (SOD) is a widely used enzyme for evaluating oxidative stress, with numerous methods being developed for its detection in biological specimens like blood, urine, and saliva. In this study, a simple metal-assisted chemical etching method was employed for the fabrication of nanostructured silicon surfaces decorated with either silver dendrites or silver aggregates. Those surfaces were used as substrates for the immunochemical determination of SOD in synthetic saliva through surface-enhanced Raman spectroscopy (SERS) and surface-enhanced fluorescence (SEF). The immunoassay was based on a 3-step competitive assay format, which included, after the immunoreaction with the specific anti-SOD antibody, a reaction with a biotinylated secondary antibody and streptavidin. Streptavidin labeled with peroxidase was used in combination with a precipitating tetramethylbenzidine substrate for detection through SERS, whereas for SEF measurements, streptavidin labeled with the fluorescent dye Rhodamine Red-X was utilized. Both immunoassays were sensitive, with a detection limit of 0.01 μg/mL and a linear dynamic range from 0.03 to 3.3 μg/mL, enabling the evaluation of the oxidative stress status of an organism.
Oxidative stress is defined by an imbalance between the generation of reactive oxygen species and the biological system’s ability to neutralize them. This condition is commonly linked to various pathological conditions [1]. Superoxide dismutase (SOD) is a widely used enzyme to assess oxidative stress, and various techniques have been developed for its detection in biological samples such as blood, urine, and saliva [2]. Surface-enhanced photoluminescence (PL) is a particularly sensitive method, offering minimal interference from the sample matrix [3]. In this work, silver nanostructured surfaces were implemented as substrates for the immunochemical determination of SOD in synthetic saliva through PL. The substrates were prepared using a single-step metal-assisted chemical etching method (MACE), resulting in the formation of silicon nanowires decorated with silver dendrites of approximately 1.5 μm in height [4]. For SOD detection, a three-step competitive immunoassay configuration was followed. Briefly, SOD was immobilized onto the substrates and then the functionalized substrates were incubated with mixtures of SOD with anti-SOD primary antibody, prepared either in assay buffer or synthetic saliva. Then, a solution of biotinylated anti-species specific antibody was added, followed by a reaction with streptavidin labelled with the fluorescent dye Rhodamine Red-X, and the signal was determined through an in-house developed optical set-up. The developed method presents similar or slightly lower sensitivity (detection limit 0.05 μg/mL) compared to the literature; however, it does not require labor-intensive sample pretreatment steps [5,6]. The aforementioned findings demonstrate the capability of the developed method to detect superoxide dismutase in natural saliva, in order to evaluate the oxidative stress status of an organism.
In this work, silicon nanowires were constructed by metal-assisted chemical etching and decorated with silver nanoparticles and used as substrates for the SERS determination of oxidative stress markers, namely glutathione, malondialdehyde and catalase. The assays were sensitive, with detection limits of 50 and 3.2 nM for glutathione and malondialdehyde, respectively, and 0.5 μg/mL for catalase, indicating the capability of the proposed substrates to be implemented for the determination of various oxidative stress markers.
The synergetic effects of electromagnetic and chemical enhancements via the combination of semiconductor nanomaterials with noble metal nanoparticles is crucial to the performance of surface-enhanced Raman scattering (SERS). Here, WO3/TiO2 photonic crystal films in the form of three-dimensional inverse opals were fabricated via the co-assembly of polymer colloidal templates with water-soluble precursors in order to simultaneously grow both constituent metal oxides with tailored electronic properties and photonic band gaps. The surface modification of compositionally tuned WO3/TiO2 inverse opals by Ag nanoparticles is demonstrated to be an efficient method to boost SERS efficiency in the detection of 4−mercaptobenzoic acid via the synergy of plasmonic effects with charge transfer and slow-light trapping.
Carbene-metal-amide (CMA) complexes of gold, silver, and copper have been studied extensively for their photochemical/photocatalytic properties and as potential (pre-)catalysts in organic synthesis. Herein, the design, synthesis, and characterization of five bench-stable Au-, Ag-, and Cu-NHC complexes bearing the benzotriazolyl anion as an amide donor, are reported. All complexes are synthesized in a facile and straightforward manner, using mild conditions. The catalytic activity of the Ag and Cu complexes was studied in propargylamide cycloisomerization and carbonyl hydrosilylation reactions. Both CMA-catalyzed transformations proceed under mild conditions and are highly efficient for a range of propargylamides and carbonyl compounds, respectively, affording the desired corresponding products in good to excellent yields.
The goal of the study presented in this paper is to evaluate the performance of a proposed adaptive beamforming approach in cell-free massive multiple input multiple output (CF-mMIMO) orientations. To this end, mobile stations (MSs) can be served by multiple access points (APs) simultaneously. In the same context, the performance of a dynamic physical resource block (PRB) allocation approach isevaluated as well, where the set of assigned PRBs per active MS is constantly updated according to their signal strength and the amount of interference that cause to the rest of the co-channel MSs. Performance evaluation takes place in a two-tier wireless orientation, employing a system-level simulator designed for parallel Monte Carlo simulations. According to the presented results, a significant gain in energy efficiency (EE) can be achieved for medium data rate services when comparing the cell-free (CF) resource allocation approach to single AP links (non-CF). This is made feasible via cooperative beamforming, where on one hand, the radiation figures of the APs that serve a particularMSare jointly updated to ensure quality of service(QoS), and on the other hand, the effects of these updates on the other MSs are evaluated as well. Although EE for high data rate services decreases compared to the non-CF scenario, the proposed dynamic PRB allocation strategy significantly lowers the number of active radiating elements required to meet minimumQoS standards, thereby reducing both hardware and computational demands.
The recent discovery of astrophysical neutrinos from the Seyfert galaxy NGC 1068 suggests the presence of nonthermal protons within a compact "coronal" region close to the central black hole. The acceleration mechanism of these nonthermal protons remains elusive. We show that a large-scale magnetic reconnection layer, of the order of a few gravitational radii, may provide such a mechanism. In such a scenario, rough energy equipartition between magnetic fields, X-ray photons, and nonthermal protons is established in the reconnection region. Motivated by recent 3D particle-in-cell simulations of relativistic reconnection, we assume that the spectrum of accelerated protons is a broken power law, with the break energy being constrained by energy conservation (i.e., the energy density of accelerated protons is at most comparable to the magnetic energy density). The proton spectrum is ${{dn}}_{p}/{{dE}}_{p}\propto {E}_{p}^{-1}$ below the break and ${{dn}}_{p}/{{dE}}_{p}\propto {E}_{p}^{-s}$ above the break, with IceCube neutrino observations suggesting s ≃ 3. Protons above the break lose most of their energy within the reconnection layer via photohadronic collisions with the coronal X-rays, producing a neutrino signal in good agreement with the recent observations. Gamma rays injected in photohadronic collisions are cascaded to lower energies, sustaining the population of electron-positron pairs that makes the corona moderately Compton thick.
Context. Very high-energy (VHE, E > 100 GeV) observations of the blazar Mrk 501 with MAGIC in 2014 provided evidence for an unusual narrow spectral feature at about 3 TeV during an extreme X-ray flaring activity. The one-zone synchrotron-self Compton scenario, widely used in blazar broadband spectral modeling, fails to explain the narrow TeV component. Aims: Motivated by this rare observation, we propose an alternative model for the production of narrow features in the VHE spectra of flaring blazars. These spectral features may result from the decay of neutral pions (π0 bumps) that are in turn produced via interactions of protons (of tens of TeV energy) with energetic photons, whose density increases during hard X-ray flares. Methods: We explored the conditions needed for the emergence of narrow π0 bumps in VHE blazar spectra during X-ray flares reaching synchrotron energies ∼100 keV using time-dependent radiative transfer calculations. We focused on high-synchrotron peaked (HSP) blazars, which comprise the majority of VHE-detected extragalactic sources. Results: We find that synchrotron-dominated flares with peak energies ≳100 keV can be ideal periods for the search of π0 bumps in the VHE spectra of HSP blazars. The flaring region is optically thin to photopion production, its energy content is dominated by the relativistic proton population, and the inferred jet power is highly super-Eddington. Application of the model to the spectral energy distribution of Mrk 501 on MJD 56857.98 shows that the VHE spectrum of the flare is described well by the sum of a synchrotron self-Compton (SSC) component and a distinct π0 bump centered at 3 TeV. Spectral fitting of simulated SSC+π0 spectra for the Cherenkov Telescope Array (CTA) show that a π0 bump could be detected at a 5σ significance level with a 30-min exposure. Conclusions: A harder VHE γ-ray spectrum than the usual SSC prediction or, more occasionally, a distinct narrow bump at VHE energies during hard X-ray flares, can be suggestive of a relativistic hadronic component in blazar jets that otherwise would remain hidden. The production of narrow features or spectral hardenings due to π0 decay in the VHE spectra of blazars is testable with the advent of CTA.
We model the spectral formation occurring in the binary X-ray pulsar (XRP) RX J0209.6‑7427 during the 2019 super-Eddington outburst. Using a theoretical model previously developed by the authors, we are able to produce spectra that closely resemble the phase-averaged X-ray spectra observed using the Nuclear Spectroscopic Telescope Array and Insight-HXMT during low- and high-luminosity states of the outburst, respectively. The theoretical model simulates the accretion of fully ionized gas in a dipole magnetic field and includes a complete description of the radiation hydrodynamics, matter distribution, and spectral formation. Type II X-ray outbursts provide an opportunity to study accretion over a large range of luminosities for the same neutron star. The analysis performed here represents the first time both the outburst low and high states of an accretion-powered XRP are modeled using a physics-based model rather than standard phenomenological fitting with arbitrary mathematical functions. We find that the outer polar cap radius remains constant and the column is more fully filled with increasing luminosity, Comptonized bremsstrahlung dominates the formation of the phase-averaged X-ray spectrum, and a negative correlation exists between cyclotron centroid energy and luminosity, as expected. The super-Eddington nature of the outburst is rendered possible owing to the low scattering cross section for photons propagating parallel to the magnetic field. We also find that emission through the column top dominates in both the low and high states, implying that the pulse profiles should have a roughly sinusoidal shape, which agrees with observed properties of ultraluminous XRPs.
We theoretically investigated the electron–surface optical phonon interaction across the long-range Fröhlich coupling in monolayer transition metal dichalcogenides, such as WS2, WSe2, MoS2, and MoSe2 monolayers, on SiC and hexagonal BN dielectric substrates. We employed the effective Hamiltonian in the K+(K−) valley of the hexagonal Brillouin zone to assess the electronic energy shifts induced by the interaction between electronic states and surface polar optical phonons. Our results indicate that the interaction between electrons and surface optical phonons depends upon the polar nature of the substrate. We have also calculated the polaronic oscillator strength, as well as the polaronic scattering rate of the lower polaron state in monolayer WS2, WSe2, MoS2, and MoSe2 on SiC and hexagonal BN dielectric substrates. As a result, we have theoretically proved the following: firstly, the enhancement of the polaronic scattering rate with temperature, and secondly, the notable influence of the careful selection of surrounding dielectrics on both the polaronic oscillator strength and the polaronic scattering rate. Thus, optimal dielectrics would be those exhibiting both elevated optical phonon energy and a high static dielectric constant.
This study delves into the exploration of wave propagation in spatially homogeneous systems governed by a Klein-Gordon–type equation with a periodically time-varying cutoff frequency. Through a combination of analytical calculations and numerical simulations, intriguing and distinctive features in the dispersion diagram of these systems are uncovered. Notably, the examined configurations demonstrate some remarkable transitions as the modulation frequency increases. These transitions encompass a transformation from a frequency gap to a wave-number (q) gap around q=0, with the transition point corresponding to a gapless Dirac dispersion with an exceptional point of degeneracy. Subsequently, the q gap undergoes a bifurcation into two symmetric gaps at positive and negative wave numbers. At this second transition point, the dispersion diagram takes the form of an imaginary Dirac dispersion relation and exhibits an isolated exceptional point at the center of the q=0 gap. These findings contribute to a deeper understanding of wave dynamics in periodically modulated media, uncovering tunable phenomena.
The synthesis and characterization of a homologous series of T-shaped {MNO}10 nitrosyl complexes of the form [M(PR3)2(NO)]+ (M = Pd, Pt; R = tBu, Ad) are reported. These diamagnetic nitrosyls are obtained from monovalent or zerovalent precursors by treatment with NO and NO+, respectively, and are notable for distinctly bent M-NO angles of ∼123° in the solid state. Adoption of this coordination mode in solution is also supported by the analysis of isotopically enriched samples by 15N NMR spectroscopy. Effective oxidation states of M0/NO+ are calculated, and metal-nitrosyl bonding has been interrogated using DFT-based energy decomposition analysis techniques. While a linear nitrosyl coordination mode was found to be electronically preferred, the M-NO and P-M-P angles are inversely correlated to the extent that binding in this manner is prevented by steric repulsion between the bulky ancillary phosphine ligands.
This study examines the impact of different turbidity products on the Aegean Sea surface physical characteristics, by performing twin-experiment simulations using a high-resolution regional ocean model. The turbidity products used include an in-situ based diffuse attenuation coefficient dataset at 490 nm (kd490, in m- 1) and a satellite derived kd490 product. Satellite turbidity products are broadly used in ocean simulations due to their spatiotemporal coverage and algorithm universality. Their validation and empirical components are trained mainly in phytoplankton driven regions and this may cause systematic differences in oligotrophic areas of variable optical properties’ composition. In the Aegean Sea, the in-situ based turbidity product accounts for the contribution of suspended particles in the solar heating profile, having further implications in the surface characteristics. The Aegean Sea upper-ocean thermohaline characteristics and general circulation patterns, reveal distinct differences between the twin-experiment simulations, showcasing mesoscale to locally induced impact of the turbidity variations. The turbidity impact on the air-sea interaction fluxes affects both thermodynamic processes i.e., solar radiation penetration and absorption in the water column, as well as dynamic processes i.e., momentum fluxes due to changes of the sea surface temperature and subsequently to the momentum drag coefficient. The Aegean Sea surface characteristics in the in-situ based turbidity product simulation, show a stronger decoupling between the North and the South Aegean Sea, when compared with the satellite derived turbidity product simulation. These results highlight the importance of incorporating more realistic turbidity products in ocean models, especially for optically complex regions such as the Aegean Sea.
This study examines the impact of different turbidity products on the Aegean Sea surface physical characteristics, by performing twin-experiment simulations using a high-resolution regional ocean model. The turbidity products used include an in-situ based diffuse attenuation coefficient dataset at 490 nm (kd490, in m− 1) and a satellite derived kd490 product. Satellite turbidity products are broadly used in ocean simulations due to their spatiotemporal coverage and algorithm universality. Their validation and empirical components are trained mainly in phytoplankton driven regions and this may cause systematic differences in oligotrophic areas of variable optical properties’ composition. In the Aegean Sea, the in-situ based turbidity product accounts for the contribution of suspended particles in the solar heating profile, having further implications in the surface characteristics. The Aegean Sea upper-ocean thermohaline characteristics and general circulation patterns, reveal distinct differences between the twin-experiment simulations, showcasing mesoscale to locally induced impact of the turbidity variations. The turbidity impact on the air-sea interaction fluxes affects both thermodynamic processes i.e., solar radiation penetration and absorption in the water column, as well as dynamic processes i.e., momentum fluxes due to changes of the sea surface temperature and subsequently to the momentum drag coefficient. The Aegean Sea surface characteristics in the in-situ based turbidity product simulation, show a stronger decoupling between the North and the South Aegean Sea, when compared with the satellite derived turbidity product simulation. These results highlight the importance of incorporating more realistic turbidity products in ocean models, especially for optically complex regions such as the Aegean Sea.
Metamaterials are a fascinating class of photonic materials since they allow us to control optical responses (largely) at will. Besides being an intellectual challenge, adding time variations into spatial metamaterials increases the degrees of freedom to tune their effective response, which motivates their exploration. However, to exploit such materials in the future design of functional devices, we may wish to treat them at the effective level to avoid considering all the mesoscopic details. To permit such effective treatment, we describe here an eigenmode-based approach to homogenize spatiotemporal metamaterials composed of a periodic arrangement of scatterers made from a time-varying material. Practically, we consider the periodic arrangement of spheres within one layer. In our two-step homogenization scheme, we first temporally homogenize that metasurface using the eigenmodes of the bulk time-varying material. Following this, we perform spatial homogenization by inverting the Fresnel coefficients of a slab made from a stationary material. These steps effectively describe the optical response of the spatiotemporal metasurface as a homogeneous slab. We validate our results by comparing the optical observables, i.e., reflectivity and transmissivity, of the metasurface with those of the homogenized slab, and we assess the limitations of the homogenization.
Categorization and identification of typical exemplars within semantic categories is a universal skill of human cognition which is involved in language development. However, cultural, and experiential aspects might influence typicality effects. This paper examines the role of native language and culture on that categorization process and on typicality effects. Towards that objective, we had Spanish native speakers and Spanish FL learners whose mother tongue is Greek complete a category generation word association task. Data were analyzed within a network and graph theory framework as the best fitting for this type of data, bearing in mind previous descriptions of semantic memory. Results showed how, indeed, native speakers and learners of varying proficiency levels differ in their availability and production of typical exemplars, especially in slot-filler categories versus taxonomic categories. Lexical access during category generation might be determined by native language and culture. Additionally, natives’ mental lexicon seems to feature denser connections responsible for more efficient access.
Uncertainty profoundly shapes modern production models and the institutional framework of economies. This study investigates the assumption that heightened uncertainty leads to reduced innovation outcomes. Using an unbalanced panel dataset of 143 countries from 1997 to 2020, the analysis reveals that increased uncertainty significantly affects economies' innovation performance. Economic institutions play a critical role in this process, acting as safeguards or enhancers under high uncertainty. Uncertainty and economic institutions work in synergy, with uncertainty exerting a more prominent impact. In advanced economies, uncertainty and economic institutions negatively influence innovation outcomes, but these economies counteract uncertainty by increasing research and development (R&D) spending. Economic institutions may limit R&D expenditure but create an environment conducive to higher researcher employment. On the other hand, developing economies experience a stronger negative effect of uncertainty compared to advanced economies, and economic institutions require support to foster innovation production. Moreover, these economies have limited capacity to mitigate uncertainty through R&D investments. Overall, this study underscores the complex relationship between uncertainty, economic institutions, and innovation outcomes across different types of economies.
Preparing prospective mathematics teachers to become teachers who recognize andrespond to students’ mathematical needs is challenging. In this study, we use the construct of critical incident as a tool to support prospective mathematics teachers’ reflection on their authentic fieldwork activities, notice students’ thinking, and link it to the complexity of mathematics teaching. Particularly, we aim to explore the characteristics and evolution of prospective mathematics teachers’ noticing of students’ mathematical thinking when critical incidents trigger reflective discussions. Critical incidents are moments in which students’ mathematical thinking becomes apparent and can provide teachers with opportunities to delve more deeply into the mathematics discussed in the lesson. In the study, twenty-two prospective mathematics teachers participated in fieldwork activities that included observing and teaching secondary school classrooms. The prospective teachers identified critical incidents from their observations and teaching, which were the foci for reflective discussion in university sessions. By characterizing the prospective teachers’ reflective talk in these discussions, we demonstrate the discussion’s evolution.In it, participants questioned learning and teaching mathematics and suggested alternate explanations. This characterization also shows that using critical incidents in the university discussions enabled the prospective teachers to link students’ thinking with the teacher’s teaching practices while supporting their reflection using classroom evidence. We emphasize the importance of descriptive talk in the discussion, which allows for deepening the prospective teachers’ reflections. Further, we explore the teacher educator’s contributions in those discussions, showing that the teacher educator mainly maintained the reflective talk by contextualizing the critical incidents and pressing the participants to explain further issues they raised in the discussions. Implications for mathematics teacher education are discussed.
The issue of interpersonal comparisons of utility is about the possibility (or not) of comparing the utility or welfare or the mental states in general, of different individuals. Embedded in the conceptual framework of utilitarianism, interpersonal comparisons were admissible in economics as part of the theoretical justification of welfare policies until the first decades of the twentieth century. Under the strong influence of the scientific philosophy of positivism as reflected in the works of early neoclassical economists and as epitomized by Lionel Robbins, utility comparisons were subsequently rejected as a value judgement. Robbins’ methodological stance is still prevalent among mainstream economists. Despite the explicit rejection of comparability by the majority of economists, interpersonal comparisons are necessary for many key policy issues, such as progressive taxation, social welfare policies, GDP-based welfare comparisons, cost–benefit analysis, and public goods provision. In this paper, the case of interpersonal utility comparisons is discussed as an illustrative example of the usefulness of the study of the role of value judgements, and generally of the interrelationship between ethics and economics. It is argued that the current tension between theory and policy practice might be resolved through the efforts of prominent economists and philosophers to challenge positivism, and especially its problematic treatment of value judgements and of ethical assumptions in general. The discussion also provides more strength to the view that policy makers and their economic advisers cannot avoid ethical questions in their analysis of the workings of the economic system
Karakousis ND, Pyrgioti EE, Georgakopoulos PN, Karagiannakis DS, Papanas N. Vitamin E and diabetic foot ulcers. Current Diabetes Reviews. 2024;20:29–32.
<p><span style="font-weight: 400;">The growing energy demand has intensified interest in marine renewable sources. This study assesses wave energy potential in the Mediterranean and Black Seas using a 15-year (2010–2024) wave hindcast with the WaveWatch III model. It examines the spatial and temporal distribution of significant wave height, wave energy period, and overall wave energy resources at a basin-wide scale. The findings identify the western Mediterranean—particularly the area west of Sardinia and from the Gulf of Lion to the Algerian coast— as having considerable wave energy potential, primarily due to the Mistral winds during winter. Other regions, such as the Alboran Sea, central-south Aegean Sea, and western Black Sea, show lower wave energy levels but remain promising for wave energy converter development due to moderate wave power variability over time. To assess the impact of wave-current interactions on wave power estimation, additional simulations were performed over a 5-year sub-period without current forcing. Results indicate that currents can reduce extreme wave power values in the most energetic areas by up to 5 kWm</span><sup><span style="font-weight: 400;">-1</span></sup><span style="font-weight: 400;">. This study establishes a baseline wave-only simulation to aid future research using a regional coupled ocean-atmosphere-wave system for more precise wave power assessments.</span></p>
The integration of renewable rnergy sources (RESs) into the power grid involves operational challenges due to the inherent RES energy-production variability. Imbalances between actual power generation and scheduled production can lead to grid instability and revenue loss for RES operators and aggregators. To address this risk, in this paper, we introduce a mutually beneficial bilateral trading scheme between a RES and a DR aggregator to internally offset real-time energy imbalances before resorting to the flexibility market. We consider that the DR aggregator manages the energy demand of users, characterized by uncertainty in their participation in DR events and thus the actual provision of flexibility, subject to their offered monetary incentives. Given that the RES aggregator faces penalties according to dual pricing for positive or negative imbalances, we develop an optimization framework to achieve the required flexibility while addressing the trade-off between maximizing the profit of the RES and DR aggregators and appropriately incentivizing the users. By using appropriate parameterization of the solution, the achievable revenue for the imbalance offsetting can be shared between the RES and the DR aggregators while keeping users satisfied. Our analysis highlights the interdependencies of the demand–production energy imbalance on user characteristics and the RES and DR aggregator profits. Based on our results, we show that a win–win outcome (for the RES and DR aggregators and the users) is possible for a wide range of cases, and we provide guidelines so that such bilateral agreements between RES and DR aggregators could emerge in practical settings.
An X-ray brightening of a source likely associated with the Be X-ray binary candidate RX J0032.9-7348 in the SMC (Kahabka, Pietsch 1996, A & A 312, 919) was recently discovered with the Einstein Probe mission (EP, ATel#16880).
Generalized inverses are extremely effective in many areas of mathematics and engineering. The zeroing neural network (ZNN) technique, which is currently recognized as the state-of-the-art approach for calculating the time-varying Moore-Penrose matrix inverse, is investigated in this study as a solution to the problem of calculating the time-varying minimum rank outer inverse (TV-MROI) with prescribed range and/or TV-MROI with prescribed kernel. As a result, four novel ZNN models are introduced for computing the TV-MROI, and their efficiency is examined. Numerical tests examine and validate the effectiveness of the introduced ZNN models for calculating TV-MROI with prescribed range and/or prescribed kernel.
This study aimed to systematically review research findings regarding the relationship between adult friendship and wellbeing. A multidimensional scope for wellbeing and its components with the use of the PERMA theory was adopted. A total of 38 research articles published between 2000 and 2019 were reviewed. In general, adult friendship was found to predict or at least be positively correlated with wellbeing and its components. In particular, the results showed that friendship quality and socializing with friends predict wellbeing levels. In addition, number of friends, their reactions to their friend's attempts of capitalizing positive events, support of friend's autonomy, and efforts to maintain friendship are positively correlated with wellbeing. Efforts to maintain the friendship, friendship quality, personal sense of uniqueness, perceived mattering, satisfaction of basic psychological needs, and subjective vitality mediated this relationship. However, research findings highlighted several gaps and limitations of the existing literature on the relationship between adult friendship and wellbeing components. For example, for particular wellbeing components, findings were non-existent, sparse, contradictory, fragmentary, or for specific populations only. Implications of this review for planning and implementing positive friendship interventions in several contexts, such as school, work, counseling, and society, are discussed.
Rhodococcus is perhaps the most promising biodesulfurization genus and is able to withstand the harsh process conditions of a biphasic biodesulfurization process. In the present work, we constructed an advanced biocatalyst harboring a combination of three genetic modifications, namely, an operon rearrangement, a promoter exchange, and a gene overlap removal. ABSTRACT Biodesulfurization poses as an ideal replacement to the high cost hydrodesulfurization of the recalcitrant heterocyclic sulfur compounds, such as dibenzothiophene (DBT) and its derivatives. The increasingly stringent limits on fuel sulfur content intensify the need for improved desulfurization biocatalysts, without sacrificing the calorific value of the fuel. Selective sulfur removal in a wide range of biodesulfurization strains, as well as in the model biocatalyst Rhodococcus qingshengii IGTS8, occurs via the 4S metabolic pathway that involves the dszABC operon, which encodes enzymes that catalyze the generation of 2-hydroxybiphenyl and sulfite from DBT. Here, using a homologous recombination process, we generate two recombinant IGTS8 biocatalysts, harboring native or rearranged, nonrepressible desulfurization operons, within the native dsz locus. The alleviation of sulfate-, methionine-, and cysteine-mediated dsz repression is achieved through the exchange of the native promoter Pdsz, with the nonrepressible Pkap1 promoter. The Dsz-mediated desulfurization from DBT was monitored at three growth phases, through HPLC analysis of end product levels. Notably, an 86-fold enhancement of desulfurization activity was documented in the presence of selected repressive sulfur sources for the recombinant biocatalyst harboring a combination of three targeted genetic modifications, namely, a dsz operon rearrangement, a native promoter exchange, and a dszA-dszB overlap removal. In addition, transcript level comparison highlighted the diverse effects of our genetic engineering approaches on dsz mRNA ratios and revealed a gene-specific differential increase in mRNA levels. IMPORTANCE Rhodococcus is perhaps the most promising biodesulfurization genus and is able to withstand the harsh process conditions of a biphasic biodesulfurization process. In the present work, we constructed an advanced biocatalyst harboring a combination of three genetic modifications, namely, an operon rearrangement, a promoter exchange, and a gene overlap removal. Our homologous recombination approach generated stable biocatalysts that do not require antibiotic addition, while harboring nonrepressible desulfurization operons that present very high biodesulfurization activities and are produced in simple and low-cost media. In addition, transcript level quantification validated the effects of our genetic engineering approaches on recombinant strains’ dsz mRNA ratios and revealed a gene-specific differential increase in mRNA levels. Based on these findings, the present work can pave the way for further strain and process optimization studies that could eventually lead to an economically viable biodesulfurization process.
Aging is the major risk factor for several life-threatening pathologies and impairs the function of multiple cellular compartments and organelles. Age-dependent deterioration of nuclear morphology is a common feature in evolutionarily divergent organisms. Lipid droplets have been shown to localize in most nuclear compartments, where they impinge on genome architecture and integrity. However, the significance of progressive nuclear lipid accumulation and its impact on organismal homeostasis remain obscure. Here, we implement non-linear imaging modalities to monitor and quantify age-dependent nuclear lipid deposition in Caenorhabditis elegans. We find that lipid droplets increasingly accumulate in the nuclear envelope, during aging. Longevity-promoting interventions, such as low insulin signaling and caloric restriction, abolish the rate of nuclear lipid accrual and decrease the size of lipid droplets. Suppression of lipotoxic lipid accumulation in hypodermal and intestinal nuclei is dependent on the transcription factor HLH-30/TFEB and the triglyceride lipase ATGL-1. HLH-30 regulates the expression of ATGL-1 to reduce nuclear lipid droplet abundance in response to lifespan-extending conditions. Notably, ATGL-1 localizes to the nuclear envelope and moderates lipid content in long-lived mutant nematodes during aging. Our findings indicate that the reduced ATGL-1 activity leads to excessive nuclear lipid accumulation, perturbing nuclear homeostasis and undermining organismal physiology, during aging.
In this paper, I discuss the notion of “repatriation” of antiquities that have been illicitly excavated and exported, against the backdrop of Greece’s attempts to achieve their return. Taking the British Museum Caryatid as my primary case study, I survey recent Greek theatre plays and children’s storybooks in order to examine how the stolen statue is invariably portrayed as the nation’s missing “daughter” or “sister”, suffering in solitary exile and eagerly awaiting “her” return. Based on this discussion, I proceed to claim that the repatriation narrative serves as a means to reconfirm Greece’s whiteness, and the Greek nation’s rightful place as part of the West. Employing the methodological tools of coloniality and crypto-coloniality, as well as the parallel modern example of Egypt, I argue that it is through such attempts at partial representation that political communities in the periphery of the West imagine themselves into being.
As a discipline deeply rooted in the turbulent nation-building days of the “long 19th c.”, archaeology is closely entangled with political discourse. Modernity, however, has also effected a breed of politics carried out through the use of archaeology, and the past’s grip on the ways we perceive our present. This paper is not a discussion of the political aspects of archaeological praxis in contemporary societies but an exploration of politics carried out through an archaeological way of thinking and acting. I call this breed of archaeologically informed politics over life “Archaeopolitics”. My main case study come from present-day Greece, and South-Eastern Europe at large, though – as my first example is bound to show – what I am describing here may be observed in many other regions of the world and in a timeframe much wider than the later 20th – early 21st c.
The sensitivity of air quality model responses to modifications in input data (e.g. emissions, meteorology and boundary conditions)or model configurations is recognized as an important issue for air quality modelling applications in support of air qualityplans. In the framework of FAIRMODE (Forum of Air Quality Modelling in Europe, https:// fairm ode. jrc. ec. europa. eu/) adedicated air quality modelling exercise has been designed to address this issue. The main goal was to evaluate the magnitudeand variability of air quality model responses when studying emission scenarios/projections by assessing the changes of modeloutput in response to emission changes. This work is based on several air quality models that are used to support model usersand developers, and, consequently, policy makers. We present the FAIRMODE exercise and the participating models, andprovide an analysis of the variability of O3and PM concentrations due to emission reduction scenarios. The key novel feature,in comparison with other exercises, is that emission reduction strategies in the present work are applied and evaluated at urbanscale over a large number of cities using new indicators such as the absolute potential, the relative potential and the absolutepotency. The results show that there is a larger variability of concentration changes between models, when the emission reductionscenarios are applied, than for their respective baseline absolute concentrations. For ozone, the variability between modelsof absolute baseline concentrations is below 10%, while the variability of concentration changes (when emissions are similarlyperturbed) exceeds, in some instances 100% or higher during episodes. Combined emission reductions are usually more efficientthan the sum of single precursor emission reductions both for O3and PM. In particular for ozone, model responses, in terms oflinearity and additivity, show a clear impact of non-linear chemistry processes. This analysis gives an insight into the impact ofmodel’ sensitivity to emission reductions that may be considered when designing air quality plans and paves the way of morein-depth analysis to disentangle the role of emissions from model formulation for present and future air quality assessments.
PURPOSE: The purpose of this study was to determine whether specific genetic polymorphisms affect the response to intravitreal anti-vascular endothelial growth factor (anti-VEGF) treatment in patients with macular oedema secondary to retinal vein occlusion (RVO). METHODS: Participants in this prospective study were 50 patients with macular oedema secondary to RVO, who were treated with intravitreal ranibizumab or aflibercept, and were followed-up for 12 months after initiation of treatment. Five single nucleotide polymorphisms (SNPs) from three different genes (APOE, PON1, SDF-1) were examined as potential predictors for treatment response to intravitreal anti-VEGF agents. RESULTS: Patients with the LL genotype of the PON1 L55M SNP had significantly higher reduction in central subfield thickness (CST) at month 12 after initiation of intravitreal anti-VEGF treatment (101.63 +/- 56.80 mum in LL vs. 72.44 +/- 39.41 mum in LM vs. 40.25 +/- 19.33 mum in MM, p = .026). Patients with the M allele of the PON1 L55M SNP were significantly associated with lower reduction in CST compared to non-carriers (68.29 +/- 38.77 mum in LM + MM vs. 101.63 +/- 56.80 mum in LL, p = .032). CONCLUSION: PON1 L55M SNP may serve as a promising genetic biomarker for predicting response to intravitreal anti-VEGF treatment in patients with macular oedema due to RVO
In this study, we present a method to estimate posterior distributions for standard accretion torque model parameters and binary orbital parameters for X-ray binaries using a nested sampling algorithm for Bayesian parameter estimation. We study the spin evolution of two Be X-ray binary systems in the Magellanic Clouds, RX J0520.5-6932 and RX J0209-7427, during major outbursts, in which they surpassed the Eddington limit. Moreover, we apply our method to the recently discovered Swift J0243.6+6124, the only known Galactic pulsating ultra-luminous X-ray source. This is an excellent candidate for studying the disc evolution at super-Eddington accretion rates, because its luminosity spans several orders of magnitude during its outburst, with a maximum LX that exceeded the Eddington limit by a factor of ~10. Our method, when applied to RX J0520.5-6932 and RX J0209-7427, is able to identify the more favourable torque model for each system, while yielding meaningful ranges for the NS and orbital parameters. Our analysis for Swift J0243.6+6124 illustrates that, contrary to the standard torque model predictions, the magnetospheric radius (Rm) and the Alfvén radius (RA) are not proportional to each other when surpassing the Eddington limit. Reported distance estimates of this source range between 5 and 7 kpc. Smaller distances require non-typical neutron star properties (i.e. mass and radius) and possibly lower radiative efficiency of the accretion column.
The names of plants cited in Hypnerotomachia Poliphili have been re-examined. According to our survey, we suggest increasing the previously published botanical entities quoted in this book; therefore, 46 botanical entities and 100 textual passages linked to botanical entries are presented, completing the previously published botanical content of Hypnerotomachia Poliphili. The botanical section of the novel Hypnerotomachia Poliphili, which constitutes a literary source of information, includes in total 331 botanical entities associated with 772 textual passages, providing aesthetic, cultural, symbolic and physical pathways that animated the world of plants.
Context. The Magellanic Clouds are our nearest star-forming galaxies. While the population of high-mass X-ray binaries (HMXBs) in the Small Magellanic Cloud is relatively well studied, our knowledge about the Large Magellanic Cloud (LMC) is far from complete given its large angular extent and the insufficient coverage with X-ray observations. Aims: We conducted a search for new HMXBs in the LMC using data from eROSITA, the soft X-ray instrument on board the Spektrum-Roentgen-Gamma satellite. Methods: After confirming the nature of eRASSU J052914.9−662446 as a hard X-ray source that is positionally coincident with an early-type star, we followed it up with optical spectroscopic observations from the South African Large Telescope (SALT) and a dedicated NuSTAR observation. Results: We study the broadband timing and spectral behaviour of the newly discovered HMXB eRASSU J052914.9−662446 through eROSITA, Swift, and NuSTAR data in X-rays and the Optical Gravitational Lensing Experiment (OGLE) and SALT RSS data at the optical wavelength. We report the detection of a spin period at 1412 s and suggest that the orbital period of the system is ∼151 days. We thereby establish that eRASSU J052914.9−662446 is an accreting pulsar. Furthermore, through optical spectroscopic observations and the detection of Hα emission, the source is identified as a Be X-ray binary pulsar in the LMC. We also investigated the variability of the source in the optical and X-ray regime over the past decades and provide estimates of the possible magnetic field strength of the neutron star.
This study examines the impact of light absorption from biomass burning (BB) brown carbon (BrC) in the Mediterranean basin from local and distant fire incidents during a typical fire season in August 2019 and under severe fire activity in August 2021. The approaches of Saleh et al. (2014) and Wang et al. (2018) are used to describe the BrC absorption within the WRF-Chem model. Focusing on three regions in the Mediterranean (around the islands of Sicily, Malta, and Crete) that are most affected by BB activity, BrC absorption approximates 5 Mm−1 in OC concentrations up to 3 μg m−3 and can approach 15 Mm−1 in extreme conditions (up to 10 μg m−3). When photochemical bleaching is considered, BrC undergoes almost immediate bleaching upon emission due to high levels of OH radical in the Mediterranean atmosphere during summertime, decreasing light absorption between 56% and 75% under both average and extreme BB conditions. Cloud formation is facilitated above the PBL due to moisture increase induced by BrC at the area of fire events, while transported drier and warmer air masses tend to dissipate cloud formation further away from the BB source. The impact of BrC absorption on irradiances is small (up to −6 W m−2 in extreme conditions) and is often overlapped by the absorption from water vapour variations. BrC direct radiative effect (DRE) is estimated at 0.04 W m−2 (∼10% of BC) in average and 0.18 W m−2 in extreme BB activity under clear sky. Under all sky, low-level clouds dissipation in 2019 with average BB emissions enhances DRE (at 0.15 W m−2), while the higher clouds dissipation in 2021 limits DRE (at 0.11 W m−2) resulting in lower DRE despite the extreme BB conditions.
Nanostructured noble metal surfaces enhance the photoluminescence emitted by fluorescent molecules, permitting the development of highly sensitive fluorescence immunoassays. To this end, surfaces with silicon nanowires decorated with silver nanoparticles in the form of dendrites or aggregates were evaluated as substrates for the immunochemical detection of two ovarian cancer indicators, carbohydrate antigen 125 (CA125) and human epididymis protein 4 (HE4). The substrates were prepared by metal-enhanced chemical etching of silicon wafers to create, in one step, silicon nanowires and silver nanoparticles on top of them. For both analytes, non-competitive immunoassays were developed using pairs of highly specific monoclonal antibodies, one for analyte capture on the substrate and the other for detection. In order to facilitate the identification of the immunocomplexes through a reaction with streptavidin labeled with Rhodamine Red-X, the detection antibodies were biotinylated. An in-house-developed optical set-up was used for photoluminescence signal measurements after assay completion. The detection limits achieved were 2.5 U/mL and 3.12 pM for CA125 and HE4, respectively, with linear dynamic ranges extending up to 500 U/mL for CA125 and up to 500 pM for HE4, covering the concentration ranges of both healthy and ovarian cancer patients. Thus, the proposed method could be implemented for the early diagnosis and/or prognosis and monitoring of ovarian cancer.
Charge injection and transport interlayers play a crucial role in many classes of optoelectronics, including organic and perovskite ones. Here, we demonstrate the beneficial role of carbon nanodots, both pristine and nitrogen-functionalized, as electron transport materials in organic light emitting diodes (OLEDs) and organic solar cells (OSCs). Pristine (referred to as C-dots) and nitrogen-functionalized (referred to as NC-dots) carbon dots are systematically studied regarding their properties by using cyclic voltammetry, Fourier-transform infrared (FTIR) and UV–Vis absorption spectroscopy in order to reveal their energetic alignment and possible interaction with the organic semiconductor’s emissive layer. Atomic force microscopy unravels the ultra-thin nature of the interlayers. They are next applied as interlayers between an Al metal cathode and a conventional green-yellow copolymer—in particular, (poly[(9,9-dioctylfluorenyl-2,7-diyl)-alt-co-(1,4-benzo-{2,1′,3}-thiadiazole)], F8BT)—used as an emissive layer in fluorescent OLEDs. Electrical measurements indicate that both the C-dot- and NC-dot-based OLED devices present significant improvements in their current and luminescent characteristics, mainly due to a decrease in electron injection barrier. Both C-dots and NC-dots are also used as cathode interfacial layers in OSCs with an inverted architecture. An increase of nearly 10% in power conversion efficiency (PCE) for the devices using the C-dots and NC-dots compared to the reference one is achieved. The application of low-cost solution-processed materials in OLEDs and OSCs may contribute to their wide implementation in large-area applications.
Here, we present an olfactory-dependent chemotaxis assay for evaluating changes in memory-like behavior in both wild-type and Alzheimer's-disease-like C. elegans models. We describe steps for synchronizing and preparing C. elegans populations and for performing isoamyl alcohol conditioning during starvation and chemotaxis assaying. We then detail counting and quantification procedures. This protocol is applicable to mechanistic exploration and drug screening in neurodegenerative diseases and brain aging.
Earth Observation (EO) is widely recognized as a powerful tool for Climate Change and Sustainability Education (CCSE); however, the uptake of EO data in schools is still limited due to technical, motivational, or informational barriers. A major factor for the exploitation of EO in schools is the availability of curriculum-relevant pedagogical content that is attractive and personally meaningful to learners. Here, we examine whether an EO-based learning scenario developed for primary schools and implemented by EO novice teachers and students, based solely on written instructions, can serve as an effective entry point for incorporating EO into schools and addressing CCSE objectives. Our study showed that: (a) cloud-based EO tools are suitable for EO-novice teachers and students, who quickly become familiar with them and grasp basic EO concepts; (b) the combined use of EO-based and place-based learning helps students bridge the local and the global perspective of Climate Change (CC) impacts; (c) EO-based educational material stimulates students’ interest for satellites and EO technology; (d) the phenomenon-based approach grabs students’ attention, provokes their curiosity, and acts as a springboard for scientific inquiry on CC impacts; and (e) our scenario’s learning approaches promoted teachers’ upskilling and intra-school collaboration.
Geomorphological and sedimentological indicators are often used to reconstruct not only coastal evolution, but also relative sea level changes. In this work, we studied the coastal sediments of Psatha bay (Alkyonides Gulf, Greece) and beachrock outcrops in order to reconstruct the coastal evolution of the area. The drillings analysis included stratigraphy, sediment texture and radiocarbon dating. Detailed mapping of the beachrocks was accomplished using DGPS-GNSS, as well as mineralogical analysis and OSL dating of beachrock samples. The new beachrock index points indicate a sea level that fell by 0.64 ± 0.13 m since 2200 ± 210 years BP and by 0.95 ± 0.13 m since 4160 ± 320 years BP, as a direct result of its location near the uplifting footwall of Psatha fault, suggesting further a rate of tectonic uplift of ~0.26 mm/yr for the late Holocene.
Geomorphological and sedimentological indicators are often used to reconstruct not only coastal evolution, but also relative sea level changes. In this work, we studied the coastal sediments of Psatha bay (Alkyonides Gulf, Greece) and beachrock outcrops in order to reconstruct the coastal evolution of the area. The drillings analysis included stratigraphy, sediment texture and radiocarbon dating. Detailed mapping of the beachrocks was accomplished using DGPS-GNSS, as well as mineralogical analysis and OSL dating of beachrock samples. The new beachrock index points indicate a sea level that fell by 0.64 ± 0.13 m since 2200 ± 210 years BP and by 0.95 ± 0.13 m since 4160 ± 320 years BP, as a direct result of its location near the uplifting footwall of Psatha fault, suggesting further a rate of tectonic uplift of ~0.26 mm/yr for the late Holocene.
In this paper, we present a systematic GIS-based approach for producing updated, upscaled, unified and reevaluated maps for the Ionian Islands of Greece, which is an area of great geological interest. In particular, Cephalonia and Lefkada are two islands with an increased and intense seismicity. Therefore, a common GIS geodatabase was produced for handling the geoinformation of the area. New upscaled (scale 1:50,000) geotechnical and seismotectonic maps of these islands were produced based on older ones. On the other hand, the corresponding maps of the islands, based on the categories of the Greek antiseismic code and Eurocode 8, were produced in an effort to correlate them. Beyond that, all the available isoseismal maps of the earthquakes that hit the Ionian Islands were gathered in an effort to evaluate them and to find possible correlations with the other types of maps. Based on the correlation results, the consideration of the Vs30 parameter in the Greek antiseismic code is proposed for a better categorization of the geological formations.
In this paper, we present a systematic GIS-based approach for producing updated, upscaled, unified and reevaluated maps for the Ionian Islands of Greece, which is an area of great geological interest. In particular, Cephalonia and Lefkada are two islands with an increased and intense seismicity. Therefore, a common GIS geodatabase was produced for handling the geoinformation of the area. New upscaled (scale 1:50,000) geotechnical and seismotectonic maps of these islands were produced based on older ones. On the other hand, the corresponding maps of the islands, based on the categories of the Greek antiseismic code and Eurocode 8, were produced in an effort to correlate them. Beyond that, all the available isoseismal maps of the earthquakes that hit the Ionian Islands were gathered in an effort to evaluate them and to find possible correlations with the other types of maps. Based on the correlation results, the consideration of the Vs30 parameter in the Greek antiseismic code is proposed for a better categorization of the geological formations.
In several MIMO system applications, the deviations of some output performance variables from their nominal values are required to be controlled independently, while the other performance variables are required to remain at their nominal value. This problem, named noninteracting control with simultaneous partial output zeroing, is important in the case of the common design of multi-model systems. To this end, the problem of a common noninteracting control with simultaneous common partial output zeroing is formulated. The present paper aims to develop a solution to the problem of multi-model normal linear time-invariant systems via regular and static measurement output feedback. The present approach follows the method developed for the solution of the common I/O decoupling problem. The main results of the paper are the introduction and the formulation of the problem at hand, the establishment of the necessary and sufficient conditions for its solvability, and the derivation of the respective general solution of the controller matrices. For the resulting closed-loop system, the additional design requirement of approximate command following a simultaneous I/O stabilizability is studied using a composite norm 2 type cost function and a metaheuristic algorithm for the derivation of the free parameters of the controller. The present results are illustrated through a numerical example of a nonlinear process with two operating points. Moreover, all the above results are successfully applied to the two-model description of a robot-tracked UGV, using a common controller feeding back measurements of the motor currents and the orientation of the vehicle.
This article considers the rituals and ceremonies celebrating the French pro-communist activist, Eugénie Cotton, president of the Union des Femmes françaises (UFF – Union of French Women) and of the Women’s International Democratic Federation (WIDF), and the way Cotton was elevated to the rank of universal authority, exemplifying virtues not unrelated to the model of the Virgin Mary. This exploration of the enactment of the female version of the cult of the leader in the communist world during the Cold War contrasts with the masculine focus of the substantial historiographical production of the last twenty years on this topic. The paper examines the circumstances that gave birth to the “Cotton cult,” the key moments in its evolution, the mechanisms of its diffusion, and the gender shifts in the process of its invention.
INTRODUCTION: Functional Hypothalamic Amenorrhea (FHA) has been associated with excessive-chronic stress, eating disorders, and weight loss. A common feature is the increased serum cortisol, but its measurement has many limitations. Currently, salivary cortisol (SC) has been proposed as a more sensitive and adequate index. AIM: To investigate the SC alterations through a 24-h period and the possible correlation with the severity of stress in women with FHA. METHODS: Between July 2019 and March 2021, 12 FHA women and 12 healthy controls of comparable age were included. Psychological, eating, and physical abnormalities were evaluated by applying equivalent validated self-questionnaires. RESULTS: No significant differences were found between FHA women and healthy individuals with respect to morning (8:00 am) serum cortisol and ACTH (522.5 ± 162.2 vs 442 ± 138.5 nmol/l; p = 0.204 and 37 ± 44.8 vs 17.4 ± 10.8 pg/ml; p = 0.186, respectively). Women with FHA had statistically significant higher morning SC compared to control subjects (21.8 ± 5.9 nmol/l vs 12.8 ± 3.8 nmol/l; p {\textless} 0.001), while no significant differences were found regarding the afternoon (4:00 pm) and midnight (12:00 am) SC. A significant positive correlation was found between morning SC and morning serum cortisol (rho = 0.532; p = 0.007), EAT-26 (rho = 0.527; p = 0.008) and HADS-Anxiety score (rho = 0.471; p = 0.02). Additionally, a significant negative correlation between morning SC and BMI was observed (rho = -0.53; p = 0.009). CONCLUSION: Compared to serum cortisol, SC seems to express better the hypercortisolemic state of women with FHA and correlates well with the underlying contributing factors. Larger studies are needed in order to confirm these results and validate the optimal SC cut-off value associated with the development of FHA.
Pancreatoduodenectomy remains a complex abdominal operation for hpb surgeons. Significant complications keep on occurring to many patients undergoing Whipple procedure. We present ten patients, who required completion pancreatectomy in the early postoperative period after Whipples procedure, due to postoperative complications. Indications for completion pancreatectomy included: Sepsis secondary to uncontrolled GRADE C postoperative pancreatic fistula, pancreatic leak and bleeding, postoperative hemorrhage, pancreatic leak with gastrointestinal anastomosis dehiscence, and hepaticojejunal anastomosis dehiscence combined with hemorrhage. Completion pancreatectomy was carried out at a mean interval of 9 days following Whipple procedure. Six patients (60%) survived the operation and discharged from the hospital, with a median survival of 21.3 months. Four patients (40%) died in the early post-operative period due to sepsis (10%) and multiple organ failure (30%). Completion pancreatectomy after pancreatoduodenectomy is rarely indicated and it can be considered as a salvage procedure in the management of severe life-threatening post pancreatic surgery complications.
BACKGROUND/OBJECTIVE (S): Completion pancreatectomy (C.P.) is one acceptable treatment of choice in clinical scenarios such as management of post-pancreatectomy complications and recurrence in the pancreatic remnant. Studies referring to completion pancreatectomy as a distinct operation are limited, without emphasizing at the operation itself, rather reporting completion pancreatectomy as a possible option for treatment of various diseases. The identification of indications of CP in various pathologies and the clinical outcomes are therefore mandatory.
METHODS: A systematic literature search was performed in the Pubmed and Scopus Databases (February 2020),guided by the PRISMA protocol, for all studies reporting CP as a surgical procedure with reference at indications for performing it combined with postoperative morbidity and/or mortality.
RESULTS: Out of 1647 studies, 32 studies from 10 countries with 2775 patients in total, of whom 561 (20.2%) CPs met the inclusion criteria and were included in the analysis. Inclusion year ranged from 1964 to 2018 and were published from 1992 until 2019. 17 studies with a total number of 249 CPs were performed for post-pancreatectomy complications. Mortality rate was 44.5% (111 out of 249). Morbidity rate was (72.6%). 12 studies with 225 CPs were performed for isolated local recurrence after initial resection with a morbidity rate of 21.5% and 0% mortality rate in the early postoperative period. Two studies with a total number of 12 patients reported CP as a treatment option for recurrent neuroendocrine neoplasms. The mortality in those studies was 8% (1/12) and the mean morbidity rate was 58.3% (7/12). Finally, CP for refractory chronic pancreatitis was presented in one study with morbidity and mortality rates of 19% and 0%, respectively.
CONCLUSION: Completion pancreatectomy is a distinct treatment option for various pathologies. Morbidity and mortality rates depend on the indications of performing CP, the status performance of the patients and whether the operation is performed electively or urgently
Neutron star high-mass X-ray binaries with superorbital modulations in luminosity host warped inner accretion disks that occult the neutron star during precession. In SMC X-1, the instability in the warped disk geometry causes superorbital period "excursions": times of instability when the superorbital period decreases from its typical value of 55 to ~40 days. Disk instability makes SMC X-1 an ideal system in which to investigate the effects of variable disk geometry on the inner accretion flow. Using the high-resolution spectral and timing capabilities of the Neutron Star Interior Composition Explorer, we examined the high state of four different superorbital cycles of SMC X-1 to search for changes in spectral shape and connections to the unstable disk geometry. We performed pulse phase-averaged and phase-resolved spectroscopy to closely compare the changes in spectral shape and any cycle-to-cycle variations. While some parameters, including the photon index and absorbing column density, show slight variations with superorbital phase, these changes are most evident during the intermediate state of the superorbital cycle. Few spectral changes are observed within the high state of the superorbital cycle, possibly indicating the disk instability does not significantly change SMC X-1's accretion process.
The Athenet network is the network of the Seismological Laboratory of the National and Kapodistrian University of Athens. We present the geophysical investigation that has been carried out at six seismological stations of the Athenet network for their site characterization. More specifically, at the location of each seismological station, four geophysical methods have been carried out: Seismic Refraction Tomography (SRT), Multichannel Analysis of Surface Waves (MASW), the Horizontal to Vertical Spectral Ratio (HVSR) technique, and Electrical Resistivity Tomography (ERT). The applied geophysical survey provided important information regarding the site characterization at the selected seismological stations, including key parameters such as the fundamental frequency fo, the shear-wave velocity VS, the average shear-wave velocity for the upper 30 m depth (VS30), the seismic bedrock depth, the soil type, and the subsurface geology. Moreover, selected elastic moduli (Poisson’s ratio, shear, bulk, and Young moduli) have been calculated. The site characterization information contributes to the determination of the amplification factors for each site that can lead to more accurate calculation of Peak Ground Acceleration (PGA) or Peak Ground Velocity (PGV) and, therefore, trustworthy Probabilistic and Stochastic Seismic Hazard Assessments. The derived fundamental frequency for the seismological stations of VILL, LOUT, THAL, and EPID have been determined to be equal to 10.4, 2.7, 1.4, and 7.1 Hz and their amplification factors to be 1.9, 3.1, 1.7, and 2.6, respectively. For stations MDRA and ATAL, these parameters could not be determined.
INTRODUCTION: The aim of this study was to investigate the possible correlation between peripheral blood biomarkers and morphological characteristics of retinal imaging in patients with retinal vein occlusion (RVO). METHODS: Participants in this cross-sectional observational study were 65 consecutive patients (65 eyes) with treatment-naive RVO, who underwent spectral-domain optical coherence tomography (SD-OCT) and fundus fluorescein angiography (FFA). In addition, peripheral blood samples were taken to evaluate full blood count and biochemical parameters. The association between imaging characteristics and laboratory parameters was examined. RESULTS: Eyes with subretinal fluid presented significantly higher neutrophil-to-lymphocyte ratios (p = 0.028). Hyperreflective foci on SD-OCT were found to be associated with higher triglyceride levels (p = 0.024). The presence of cysts on SD-OCT was associated with significantly higher triglycerides (p = 0.010). Central subfield thickness (CST) higher than 464 mum was associated with higher lymphocyte count (p = 0.016) and higher urea (p = 0.015). No significant associations were found between laboratory parameters and intraretinal fluid, ellipsoid zone and external limiting membrane condition, or epiretinal membrane and macular ischemia. CONCLUSIONS: Specific imaging morphological characteristics were found to be associated with laboratory parameters in patients with RVO. These findings may help reveal the pathophysiology of RVO and its correlation with the development of specific clinical signs, while they could guide individualized treatment
Cosmetic labiaplasty is a form of Female Genital Cosmetic Surgery (FGCS) that is performed with the deliberate intent to alter the appearance and morphology of the external genitalia in the absence of medical concerns. Over the last decade, there is an increasing demand for FGCS and the industry behind it is constantly growing. Adolescents comprise an extremely vulnerable population, with labiaplasties in this particular age group having also increased. However, labiaplasty has been widely contested due to the irrevocable alteration of a psychosexually significant body part on minors too young to consent. Besides, the changes that occur during pubertal development in the genital area can significantly alter pediatric surgical results. Genital anatomy is more diverse than we previously thought and there is evidence to suggest that the labia minora with their rich innervation play an important role in sexual arousal and pleasure. Education regarding the wide range of normal genital appearance suffices in most cases to dissolve concerns regarding body self-image. Mental health issues should always be explored and, if identified, the girl should be referred to an experienced professional for their resolution. Postponing labiaplasty until adulthood is strongly recommended to help adolescents achieve a well-informed decision regarding an irreversible procedure with possible adverse esthetic and functional outcomes.
Mitochondria are highly dynamic organelles that serve as the primary cellular energy-generating system. Apart from ATP production, they are
essential for many biological processes, including calcium homeostasis,
lipid biogenesis, ROS regulation and programmed cell death, which
collectively render them invaluable for neuronal integrity and function.
Emerging evidence indicates that mitochondrial dysfunction and altered
mitochondrial dynamics are crucial hallmarks of a wide variety of
neurodevelopmental and neurodegenerative conditions. At the same time, the
gut microbiome has been implicated in the pathogenesis of several
neurodegenerative disorders due to the bidirectional communication between
the gut and the central nervous system, known as the gut-brain axis. Here
we summarize new insights into the complex interplay between mitochondria,
gut microbiota and neurodegeneration, and we refer to animal models that
could elucidate the underlying mechanisms, as well as novel interventions
to tackle age-related neurodegenerative conditions, based on this
intricate network.
On October 30, 2020, 11:51 UTC, a large shallow earthquake of moment magnitude Mw7.0 ruptured the eastern Aegean Sea area and affected several Greek islands, mainly Samos, as well as the Izmir area, western Turkey. A moderate damaging tsunami followed the earthquake and inundated many coastal zones in the area. At 12:15 UTC, the Greek Civil Protection sent to the residents of the eastern Aegean Sea Greek islands a tsunami alert via SMS through the single European emergency phone number 112. It has been the first time that a tsunami warning was publicly issued in the frame of the North-East Atlantic and Mediterranean Tsunami Warning System (NEAMTWS/IOC/UNESCO) since the system became operational during the summer of 2012. Through an on-line questionnaire survey conducted soon after the event we investigated the impact the tsunami 112 alert message had among the population. The aim of this study is to assess the effectiveness of the 112 number as a tool for tsunami early warning, to look after possible weaknesses that may need future improvements and to better understand the level of tsunami risk awareness among the population. The response received from 344 citizens clearly indicates that the particular tsunami alert in general had positive impact to the message recipients, but highlights several weaknesses of the tsunami emergency management chain in Greece and demonstrates some aspects of the 112 system that need improvement.
This study introduces an innovative Cumulative Link Modeling approach to monitor crop progress over large areas using remote sensing data. The models utilize the predictive attributes of calendar time, thermal time, and the Normalized Difference Vegetation Index (NDVI). Two distinct issues are tackled: real-time crop progress prediction, and completed season fitting. In the context of prediction, the study presents two model variations, the standard one based on the Multinomial distribution and a novel one based on the Multivariate Binomial distribution. In the context of fitting, random effects are incorporated to capture the inherent inter-seasonal variability, allowing the estimation of biological parameters that govern crop development and determine stage completion requirements. Theoretical properties in terms of consistency, asymptotic normality, and distribution-misspecification are reviewed. Model performance was evaluated on eight crops, namely corn, oats, sorghum, soybeans, winter wheat, alfalfa, dry beans, and millet, using in-situ data from Nebraska, USA, spanning a 20-year period. The results demonstrate the wide applicability of this approach to different crops, providing real-time predictions of crop progress worldwide, solely utilizing open-access data. To facilitate implementation, an ecosystem of R packages has been developed and made publicly accessible under the name Ages of Man.
We report comprehensive spectral and temporal properties of the Be/X-ray binary pulsar SMC X-2 using X-ray observations during the 2015 and 2022 outbursts. The pulse profile of the pulsar is unique and strongly luminosity dependent. It evolves from a broad-humped into a double-peaked profile above luminosity 3 × 1038 erg s-1. The pulse fraction of the pulsar is found to be a linear function of luminosity as well as energy. We also studied the spectral evolution of the source during the latest 2022 outburst with NICER. The observed photon index shows a negative and positive correlation below and above the critical luminosity, respectively, suggesting evidence of spectral transition from the sub-critical to supercritical regime. The broad-band spectroscopy of four sets of NuSTAR and XRT/NICER data from both outbursts can be described using a cut-off power-law model with a blackbody component. In addition to the 6.4 keV iron fluorescence line, an absorption-like feature is clearly detected in the spectra. The cyclotron line energy observed during the 2015 outburst is below 29.5 keV, however latest estimates in the 2022 outburst suggest a value of 31.5 keV. Moreover, an increase of 3.4 keV is detected in the cyclotron line energy at equal levels of luminosity observed in 2022 with respect to 2015. The observed cyclotron line energy variation is explored in terms of accretion induced screening mechanism or geometrical variation in line forming region.
On 6 February 2023, southeastern Turkey was struck by two major earthquakes that devastated 11 provinces. Tens of thousands of buildings collapsed and more were later demolished. During post-event field surveys conducted by the authors, several disposal sites set up in the most affected provinces were detected and checked for suitability. Based on field observations on the properties of sites and their surrounding areas as well as on the implemented debris management activities, it is concluded that all sites had characteristics that did not allow them to be classified as safe for earthquake debris management. This inadequacy is mainly attributed to their proximity to areas, where thousands of people reside. As regards the environmental impact, these sites were operating within or close to surface water bodies. This situation reveals a rush for rapid recovery resulting in serious errors in the preparation and implementation of disaster management plans. In this context, measures for effective debris management are proposed based on the existing scientific knowledge and operational experience. This paper aims to highlight challenges during earthquakes debris management and related threats posed to public health and the environment in order to be avoided in future destructive events.
Wastewater analysis is the most attractive alternative way for the quantification and variant profiling of SARS-CoV-2. Infection dynamics can be monitored by RT-qPCR assays while NGS can provide evidence for the presence of existing or new emerging SARS-CoV-2 variants. Herein, apart from the infection dynamic in Attica since June 1st, 2021, the monitoring of 9 mutations of the omicron and 4 mutations of the delta SARS-CoV-2 variants, utilizing both novel Nested-Seq and RT-PCR, is reported and the substitution of the delta variant (B.1.617.2) by the omicron variant (B.1.1.529) in Attica, Greece within approximately one month is highlighted. The key difference between the two methodologies is discovery power. RT-PCR can only detect known sequences cost-effectively, while NGS is a hypothesis-free approach that does not require prior knowledge to detect novel genes. Overall, the potential of wastewater genomic surveillance for the early discovery and monitoring of variants important for disease management at the community level is underlined. This is the first study, reporting the SARS-CoV-2 infection dynamic for an extended time period and the first attempt to monitor two of the most severe variants with two different methodologies in Greece.
Cellular and molecular immune components play a crucial role in the development and perpetuation of human malignancies, shaping anti-tumor responses. A novel immune regulator is interleukin-37 (IL-37), already shown to be involved in the inflammation associated with the pathophysiology of many human disorders, including cancer. The interplay between tumor and immune cells is of great importance, especially for highly immunogenic tumors such as bladder urothelial carcinoma (BLCA). This study aimed to investigate the potential of IL-37 and its receptor SIGIRR (single immunoglobulin IL-1-related receptor) to serve as prognostic and/or diagnostic markers in patients with BLCA. To this end, a series of bioinformatics tools processing -omics datasets and specifically designed qPCR assays on human BLCA tumors and cancer cell lines were utilized. Bioinformatics analysis revealed that IL-37 levels correlate with BLCA tumor development and are higher in patients with longer overall survival. Furthermore, mutations on SIGIRR are associated with enhanced infiltration of the tumor by regulatory T cells and dendritic cells. Based on the qPCR validation experiments, BLCA epithelial cells express the IL-37c and IL-37e isoforms, while the latter is the predominant variant detected in tumor biopsies, also associated with higher grade and the non-muscle-invasive type. This is the first time, to the best of our knowledge, that IL-37 and SIGIRR levels have been assessed in BLCA tumor lesions, and associations with pathological and survival parameters are described, while a transcript variant-specific signature is indicated to have a diagnostic potential. These data strongly indicate the need for further investigation of the involvement of this cytokine and interconnected molecules in the pathophysiology of the disease and its prospective as a therapeutic target and biomarker for BLCA.
The diffuse attenuation coefficient is an indicator of light availability in the surface layer, and is used in a broad range of applications, including numerical simulations, for the parameterization of the light transmission in the water column. In this study, a new dataset of the diffuse attenuation coefficient for the Eastern Mediterranean Sea test case is developed using an existing optical dataset of 2614 beam attenuation coefficient profiles. This method introduces a way of overcoming the difficulty of measuring the diffuse attenuation coefficient in-situ by utilizing the most routinely measured variable, the beam attenuation coefficient. The proposed approach uses existing semi-analytical relationships and a neural network. The neural network, a multi-layer perceptron regression model, is trained and validated with a dataset of 29398 concurrent bio-optical in-situ measurements from the PROSOPE cruise and remotely sensed surface variables. The model is applied to the Eastern Mediterranean dataset and the results are interpolated into a gridded gap-free field, with a grid resolution of 0.0416° x 0.0416°, which is assessed and compared with a satellite-derived product, investigating their significant differences. The resulting field's mean value is slightly reduced with respect to the satellite product, showing regions of higher turbidity, with the most prominent located in the northern Aegean Sea in regions of excess colored dissolved organic matter and around mesoscale features and in the Cretan and Levantine Sea in regions of higher mesoscale activity.
Let $K$ be an infinite field of characteristic $p>0$ and let $\lambda, \mu$ be partitions, where $\mu$ has two parts. We find sufficient arithmetic conditions on $p, \lambda, \mu$ for the existence of a nonzero homomorphism $\Delta(\lambda) \to \Delta (\mu)$ of Weyl modules for the general linear group $GL_n(K)$. Also for each $p$ we find sufficient conditions so that the corresponding homomorphism spaces have dimension at least 2.
INTRODUCTION: Antidepressants are widely used for the pharmacological treatment of anxiety and mood disorders. Since the eruption of the SARS-COV-2 pandemic and the later development of targeted treatments against COVID-19, inevitably many patients receive antidepressants as well as targeted treatments against COVID-19 against COVID-19. Co-administration of antidepressants with COVID-19 therapeutics has the potential of drug-drug interactions, of varying severity and clinical significance. AREAS COVERED: This is a curated narrative review of the current state of the art regarding drug-drug interactions between COVID-19 therapeutics and medications licensed for the pharmacotherapy of depression. A systematic search of electronic databases, using as keywords the international nonproprietaty names of currently approved COVID-19 therapeutics and antidepressants was performed, and additionally online interaction checker tools were consulted. Derived data were synthesized for each COVID-19 therapeutic and presented with up-to-date guidance. EXPERT OPINION: Several COVID-19 therapeutics have potential for drug-drug interactions with antidepressants. Remdesivir and Nirmatrelvir-Ritonavir have the higher risk, whereas several monoclonal antibodies appear safer. The most serious drug-drug interactions (serotonin syndrome and QTc prolongation) require close monitoring; however, DDI toward reducing the efficacy of antidepressants may be difficult to recognize. As COVID-19 treatment protocols take precedence, psychiatrists should exert flexibility in antidepressant use and proactively monitor treatment progress.
We present the first results for the dust-scattering rings of GRB 221009A, coined as the gamma-ray bursts (GRBs) of the century, as observed by the Neil Gehrels Swift Observatory. We perform analysis of both time resolved observations and stacked data. The former approach enable us to study the expansion of the most prominent rings, associate their origin with the prompt X-ray emission of the GRB and determine the location of the dust layers. The stacked radial profiles increase the signal-to-noise ratio of the data and allows detection of fainter and overlapping peaks in the angular profile. We find a total of 16 dust concentrations (with hints of even more) that span about 15kpc in depth and could be responsible for the highly structured X-ray angular profiles. By comparing the relative scattered fluxes of the five most prominent rings we show that the layer with the largest amount of dust is located at about 0.44 kpc away from us. We finally compare the location of the dust layers with results from experiments that study the 3D structure of our Galaxy via extinction or CO radio observations, and highlight the complementarity of dust X-ray tomography to these approaches.
We report on NICER observations of the Be X-ray binary 4U 0115+63 during the rise of the source's current historic outburst, which began around 2023 March 28 and is the brightest recorded in 27 years.
On 6 February 2023, East Anatolia was devastated by two major earthquakes resulting in hundreds of thousands of collapses and tens of thousands of human casualties. This paper investigates the factors related to building properties and earthquake environmental effects (EEEs) that contributed to the building damage grade and distribution in southeastern Turkey. In regards to the building construction properties, the loose enforcement of the building code, the random urban planning solutions and the poor construction standards are the main construction deficiencies that led to one of the largest disasters in Turkey’s recent history. Regarding geological factors, the triggering of primary and secondary EEEs largely shaped the grade and distribution of damage. Where coseismic surface ruptures intersected with the built environment, heavy to very heavy structural damage was observed. This was evident in many cases along the ruptured segments of the East Anatolian Fault Zone (EAFZ). Liquefaction observed close to waterbodies caused damage typical of building foundation load-bearing capacity loss. The earthquake-triggered landslides affected mainly mountainous and semi-mountainous settlements characterized with pre-earthquake high related susceptibility. The high susceptibility to generation of EEEs was extensively confirmed in many cases resulting in extensive damage. The provided information highlights the importance of such studies for hazard mitigation and disaster risk reduction.
This paper explores the efficacy of the geoeducational assessment method (GEOAM) in evaluating the geoeducational potential of geosites. Leveraging a case study involving four geotopes on the island of Samos, Aegean Sea, Greece, this study examines the strengths and limitations of the GEOAM approach, aiming to comprehensively elucidate its efficacy. The assessment outcomes illuminate the vital role of targeted strategies in enhancing the educational and sustainable impact of geosites, thereby fostering geological understanding and responsible environmental engagement. A prominent finding is the urgency to address the gap in foundational geological knowledge, underscored by the need for robust geoeducation programs at schools and the augmented presence of geologists. While acknowledging potential limitations, including subjectivity in scoring and data availability constraints, this study underscores the method’s broader contribution to societal goals. By integrating geoethic principles, GEOAM offers a comprehensive framework aligning with the objectives of geological comprehension and environmentally conscious practices.
This paper investigates the relationship between investors' attention, as measured by Google search queries, and equity implied volatility during the COVID-19 outbreak. Recent studies show that search investors' behavior data is an extremely abundant repository of predictive data, and investor-limited attention increases when the uncertainty level is high. Our study using data from thirteen countries across the globe during the first wave of the COVID-19 pandemic (January–April 2020) examines whether the search “topic and terms” for the pandemic affect market participants’ expectations about future realized volatility. With the panic and uncertainty about COVID-19, our empirical findings show that increased internet searches during the pandemic caused the information to flow into the financial markets at a faster rate and thus resulting in higher implied volatility directly and via the stock return-risk relation. More specifically for the latter, the leverage effect in the VIX becomes stronger as Google search queries intensify. Both the direct and indirect effects on implied volatility, highlight a risk-aversion channel that operates during the pandemic. We also find that these effects are stronger in Europe than in the rest of the world. Moreover, in a panel vector autoregression framework, we show that a positive shock on stock returns may soothe COVID-related Google searches in Europe. Our findings suggest that Google-based attention to COVID-19 leads to elevated risk aversion in stock markets.
Defining efficient families of recurrent neural networks (RNN) models for solving time-varying nonlinear equations is an interesting research topic in applied mathematics. Accordingly, one of the underlying elements in designing RNN is the use of efficient nonlinear activation functions. The role of the activation function is to bring out an output from a set of input values that are supplied into a node. Our goal is to define new family of activation functions consisting of a fixed gain parameter and a functional part. Corresponding zeroing neural networks (ZNN) is defined, termed as varying-parameter improved zeroing neural network (VPIZNN), and applied to solving time-varying nonlinear equations. Compared with previous ZNN models, the new VPIZNN models reach an accelerated finite-time convergence due to the new time-varying activation function which is embedded into the VPIZNN design. Theoretical results and numerical experiments are presented to demonstrate the superiority of the novel VPIZNN formula. The capability of the proposed VPIZNN models are demonstrated in studying and solving the Van der Pol equation and finding the root $$\root m \of {a(t)}$$.
In recent years, advances in science and technology have improved our quality of life, enabling us to tackle diseases and increase human life expectancy. However, longevity is accompanied by an accretion in the frequency of age-related neurodegenerative diseases, creating a growing burden, with pervasive social impact for human societies. The cost of managing such chronic disorders and the lack of effective treatments highlight the need to decipher their molecular and genetic underpinnings, in order to discover new therapeutic targets. In this effort, the nematode serves as a powerful tool to recapitulate several disease-related phenotypes and provides a highly malleable genetic model that allows the implementation of multidisciplinary approaches, in addition to large-scale genetic and pharmacological screens. Its anatomical transparency allows the use of co-expressed fluorescent proteins to track the progress of neurodegeneration. Moreover, the functional conservation of neuronal processes, along with the high homology between nematode and human genomes, render extremely suitable for the study of human neurodegenerative disorders. This review describes nematode models used to study neurodegeneration and underscores their contribution in the effort to dissect the molecular basis of human diseases and identify novel gene targets with therapeutic potential.
Transplant-associated thrombotic microangiopathy (TMA) occurs in a significant percentage of patients after allogeneic stem cell transplantation (allo-SCT) and is associated with significant morbidity and mortality. The aim of the present study was to examine the association of serum angiopoetin-2 (Ang2) levels and the presence of antibodies against angiotensin II type 1 (AT1R) and ndothelin A Recreptor (ETAR) with the outcome of patients with TMA and/or graft-versus-host disease (GVHD) after allo-SCT. Analysis of our data showed that elevated serum Ang2 levels at the time of TMA diagnosis are significantly associated with increased non-relapse mortality and decreased overall survival. To our knowledge, this is the first study demonstrating an association between raised Ang2 levels and poor outcomes in patients with TMA. Antibodies against AT1R (AT1R-Abs) and ETAR (ETAR-Abs) were detected in 27% and 23% of the patients, respectively, but there was no association between the presence of autoantibodies and the outcome of patients with TMA. However, a significant finding was the strong positive correlation between the presence of AT1R-Abs with the occurrence of chronic fibrotic GVHD, such as scleroderma and cryptogenic organizing pneumonia, raising the possibility of the contribution of autoantibodies in the pathogenesis of fibrotic GVHD manifestations
In this study, we developed active substrates consisting of Ag-decorated silicon nanowires on a Si substrate using a single-step Metal Assisted Chemical Etching (MACE) process, and evaluated their performance in the identification of low concentrations of Rhodamine 6G using surface-enhanced photoluminescence spectroscopy. Different structures with Ag-aggregates as well as Ag-dendrites were fabricated and studied depending on the etching parameters. Moreover, the addition of Au nanoparticles by simple drop-casting on the MACE-treated surfaces can enhance the photoluminescence significantly, and the structures have shown a Limit of Detection of Rhodamine 6G down to 10−12 M for the case of the Ag-dendrites enriched with Au nanoparticles.
Context. During the third all-sky survey (eRASS3), eROSITA, the soft X-ray instrument aboard Spectrum-Roentgen-Gamma, detected a new hard X-ray transient, eRASSt J040515.6 − 745202, in the direction of the Magellanic Bridge. Aims: We arranged follow-up observations and searched for archival data to reveal the nature of the transient. Methods: Using X-ray observations with XMM-Newton, NICER, and Swift, we investigated the temporal and spectral behaviour of the source for over about 10 days. Results: The X-ray light curve obtained from the XMM-Newton observation with an ∼28 ks exposure revealed a type-I X-ray burst with a peak bolometric luminosity of at least 1.4 × 1037 erg s−1. The burst energetics are consistent with a location of the burster at the distance of the Magellanic Bridge. The relatively long exponential decay time of the burst of ∼70 s indicates that it ignited in a H-rich environment. The non-detection of the source during the other eROSITA surveys, twelve and six months before and six months after eRASS3, suggests that the burst was discovered during a moderate outburst which reached 2.6 × 1036 erg s−1 in persistent emission. During the NICER observations, the source showed alternating flux states with the high level at a similar brightness as during the XMM-Newton observation. This behaviour is likely caused by dips as also seen during the last hour of the XMM-Newton observation. Evidence for a recurrence of the dips with a period of ∼21.8 h suggests eRASSt J040515.6 − 745202 is a low-mass X-ray binary (LMXB) system with an accretion disk seen nearly edge on. We identify a multi-wavelength counterpart to the X-ray source in UVW1 and g, r, i, and z images obtained by the optical/UV monitor on XMM-Newton and the Dark Energy Camera at the Cerro Tololo Inter-American Observatory. The spectral energy distribution is consistent with radiation from an accretion disk which dominates the UV and from a cool late-type star detected in the optical to infrared wavelengths. Conclusions: After the discovery of X-ray bursts in M 31, the Magellanic Bridge is only the second location outside of the Milky Way where an X-ray burster was found. The burst uniquely identifies eRASSt J040515.6 − 745202 as an LMXB system with a neutron star. Its location in the Magellanic Bridge confirms the existence of an older stellar population which is expected if the bridge was formed by tidal interactions between the Magellanic Clouds, which stripped gas and stars from the clouds.
The La1-xCaxMnO3 series of compounds with antiferromagnetic ground states (x 1/2) have been extensively studied due to the novel spin, orbital, and charge-ordering states observed when the calcium concentration is a simple fraction (x = 1/2, 2/3, and 3/4). The ground states of these compositions have been explained by the Goodenough charge, orbital, and spin ordering model. An important issue remaining is the elucidation of how the ground state changes when x is not a simple number. Here we study the magnetic structure of La1-xCaxMnO3 for 0.51 x 0.69 using powder neutron diffraction measurements supported by magnetization data. For compositions with 0.51 x 0.56, the magnetic structure, which we term as an incommensurate charge exchange (CE) structure can be described by two propagation vectors kC = [1/2, 0, 1/2] and kE = [6E, 0, 1/2]. In the second one, the component parallel to the a* axis of the reciprocal lattice changes with the Mn4+ concentration x as 6E approximate to x - 1/2 providing, thus, an unambiguous signature of the adoption of an incommensurate magnetic structure. As x gradually increases, the diffraction data reveal that two magnetic phases-one adopting the incommensurate CE, and one adopting the commensurate "2/3" magnetic structure-co-exist in the concentration regime of 0.57 x 0.61. Around the simple fraction x = 2/3, the magnetic structure can be also described by three propagation vectors, the commensurate kE = [0, 0, 1/2], kC = [1/2, 0, 1/2], and an incommensurate k2/3 = [1/3 + 62/3, 0, 1/2] propagation vector with 62/3 taking negative/zero/positive values for x smaller than/equal to/larger than 2/3, respectively. Our experimental results for 0.51 x 0.56 are neither in favor of a stripe structure consisting of a fine mixture of x = 1/2 and x = 2/3 phases (phase separation) nor of a defect structure in which an appropriate amount of Mn3+-O sheets have been replaced by Mn4+-O sheets (defect structure). A sinusoidal modulated structure has been used as a possible candidate in explaining the experimental neutron diffraction magnetic Bragg peaks. This result may be linked to the presence of a mixed orbital state of the manganese ions.
The main contribution of this paper is to develop explicit expressions for the Drazin inverse of two kinds of anti-triangular block complex matrices under new assumptions. Further, we apply our results to obtain new formulae for the Drazin inverse of a 2 × 2 block complex matrix. We present a list of well-known results which are recovered in this paper. We give three examples to illustrate our new explicit expressions.
Previous research findings demonstrate that both savoring ability and the presence of high-quality friendships play a significant role in enhancing one’s overall sense of wellbeing. However, these associations have not been thoroughly investigated within a diverse range of adults across their lifespans, nor have they been explored in the specific cultural context of Greece. Thus, the primary objective of this study was to delve into the relationships between close friendship quality, the utilization of savoring techniques, and wellbeing within the Greek cultural framework. The study involved 771 adults from Greece with an average age of 38.35 years, who completed the McGill Friendship Functions Questionnaire, the PERMA Profiler, and the Abridged Ways of Savoring Checklist. Results revealed that there exists a positive correlation between friendship quality and savoring strategies with overall wellbeing. Moreover, the study identified a significant association wherein a greater employment of savoring strategies was linked to higher levels of friendship quality. While this study contributes valuable insights, it also has limitations that warrant acknowledgment. Furthermore, suggestions for potential future research directions are proposed, and the implications of these findings are discussed in relation to interventions aimed at enhancing both friendships and the practice of savoring across various contexts.
The relationship between humans and the environment in the modern world is challenging. UNESCO Global Geoparks are current holistic approaches for protecting and managing geographical areas that emphasise local communities and sustainability. This paper attempts to review the grey literature of Greek universities through their academic repositories, regarding the research field referred to as Greek UNESCO Global Geoparks from 2000 to 2022 and using the keyword “Geopark” to determine possible future research directions. Through the systematic literature review methodology, from 138 bibliographic sources, 28 were selected, which met the predefined criteria. In general, there is a growing scientific–academic interest in Geoparks, which mainly concerns the aspects of geotourism (n = 7), geology (n = 6), management (n = 4), and education (n = 4). Future research directions may focus on promoting the socio-economic and cultural aspects of Geoparks, investing in collaborative management and governance of Geoparks, facing climate change and environmental challenges in Geoparks, and enhancing Geoenvironmental Education in Geoparks. Such approaches may serve the United Nation’s Seventeen Sustainable Development Goals and cultivate cognitive and emotional bonds between local populations and the geoenvironment.
BACKGROUND: Males with 5$\alpha$-reductase deficiency experience oligospermia or azoospermia, resulting in fertility problems. OBJECTIVE: The aim of the present systemic review was to assess the fertility status of males with 5$\alpha$-reductase type 2 deficiency and explore how reproduction can be achieved in these patients. STUDY DESIGN: An extensive search of two databases (Pubmed and SCOPUS) was performed. Studies with original clinical data in patients with 5$\alpha$-reductase deficiency evaluating the impact of the disease on semen quality and quantity and pregnancy outcomes through assisted or natural conception methods were eligible to be included in this systematic review. RESULTS: A total of nine cases were identified based on the eligibility criteria, all of which included reports of successful reproduction in males with 5$\alpha$-reductase type 2 deficiency. DISCUSSION: In five individuals, assisted reproduction technology was used to achieve conception, highlighting its importance in solving the fertility problems that males with 5$\alpha$-reductase deficiency are facing. Potential future fertility is a further indication for assigning the male gender in diagnosed newborns. CONCLUSION: In order to achieve this, the development of a management plan starting at birth is crucial for these patients, so that spermatogenesis and potential fertility can be preserved. In adulthood, semen analysis and mutation screening may also help in guiding these patients to select the correct fertilization method for their individual genetic and phenotypic characteristics.
The concept of Finite Absorption Time (FAT) for oral drug administration is set to affect pharmacokinetic analyses, Physiologically-based Pharmacokinetics simulations, and Pharmacometrics.
Identification of differentially expressed proteins (DEPs) in first trimester maternal plasma between pregnant women with a subsequent spontaneous moderate/late Preterm Delivery (sPTD) and women who delivered at term. The sPTD group consisted of women who delivered between 32°/7 and 366/7?weeks of gestation. Isobaric tags for relative and absolute quantification (iTRAQ) coupled with LC?MS/MS was used for the analysis of five first trimester maternal plasma samples obtained from women with a subsequent moderate/late preterm sPTD and five women with term deliveries. Enzyme-linked immunosorbent assay (ELISA) was further applied in an independent cohort of 29 sPTD cases and 29 controls to verify the expression levels of selected proteins. 236 DEPs, mainly linked to coagulation and complement cascade, were identified in first trimester maternal plasma obtained from the sPTD group. Decreased levels of selected proteins, namely, VCAM-1, SAA, and Talin-1, were further confirmed using ELISA, highlighting their potential as candidate predictive biomarkers for sPTD at32°/7 and 366/7?weeks of gestation. First trimester maternal plasma proteomic analysis revealed protein changes associated with subsequent moderate/late preterm sPTD.
Gamma-ray flares of blazars may be accompanied by high-energy neutrinos due to interactions of high-energy cosmic rays in the jet with photons, as suggested by the detection of the high-energy neutrino IceCube-170922A during a major gamma-ray flare from blazar TXS 0506+056 at the ~3σ significance level. In this work, we present a statistical study of gamma-ray emission from blazars to constrain the contribution of gamma-ray flares to their neutrino output. We construct weekly binned light curves for 145 gamma-ray bright blazars in the Fermi Large Area Telescope Monitored Source List adding TXS 0506+056. We derive the fraction of time spent in the flaring state (flare duty cycle) and the fraction of energy released during each flare from the light curves with a Bayesian blocks algorithm. We find that blazars with lower flare duty cycles and energy fractions are more numerous among our sample. We identify a significant difference in flare duty cycles between blazar subclasses at a significance level of 5%. Then using a general scaling relation for the neutrino and gamma-ray luminosities, ${L}_{\nu }\propto {({L}_{\gamma })}^{\gamma }$ with a weighting exponent of γ = 1.0-2.0, normalized to the quiescent gamma-ray or X-ray flux of each blazar, we evaluate the neutrino energy flux of each gamma-ray flare. The gamma-ray flare distribution indicates that blazar neutrino emission may be dominated by flares for γ ≳ 1.5. The neutrino energy fluxes for 1 week and 10 yr bins are compared with the decl.-dependent IceCube sensitivity to constrain the standard neutrino emission models for gamma-ray flares. Finally, we present the upper-limit contribution of blazar gamma-ray flares to the isotropic diffuse neutrino flux.
Employee attrition, defined as the voluntary resignation of a subset of a company’s workforce, represents a direct threat to the financial health and overall prosperity of a firm. From lost reputation and sales to the undermining of the company’s long-term strategy and corporate secrets, the effects of employee attrition are multidimensional and, in the absence of thorough planning, may endanger the very existence of the firm. It is thus impeccable in today’s competitive environment that a company acquires tools that enable timely prediction of employee attrition and thus leave room either for retention campaigns or for the formulation of strategical maneuvers that will allow the firm to undergo their replacement process with its economic activity left unscathed. To this end, a weights and structure determination (WASD) neural network utilizing Fresnel cosine integrals in the determination of its activation functions, termed FCI-WASD, is developed through a process of three discrete stages. Those consist of populating the hidden layer with a sufficient number of neurons, fine-tuning the obtained structure through a neuron trimming process, and finally, storing the necessary portions of the network that will allow for its successful future recreation and application. Upon testing the FCI-WASD on two publicly available employee attrition datasets and comparing its performance to that of five popular and well-established classifiers, the vast majority of them coming from MATLAB’s classification learner app, the FCI-WASD demonstrated superior performance with the overall results suggesting that it is a competitive as well as reliable model that may be used with confidence in the task of employee attrition classification.
The present work is an attempt at a bibliographic overview in the field of paleontology and specifically in the field of fossils regarding their value and connection with history and mythology, and how it has been used to teach theory of evolution through natural selection (TENS) in a university course. To make our case, we use as our paradigm two well-known historical locations of Greece, namely Thermopiles and Marathon. The area of Marathon includes the location of Pikermi, which is very well known for its fossils that historically have been one of the first locations rich in fossils that have been studied so extensively. Before we make a short tour of other similar locations of the Greek peninsula that are good cases for teaching evolution using paleontology, we present an example of how fossils can be formed via sedimentation. For that, we are using the case of Thermopile, while in antiquity was chosen as the field of the famous battle as it was a very narrow strip of land between the mountain and the sea, nowadays, due to sedimentary alluvial deposits, has become a rather large field. To make the reader familiar with the fossils found around Greece and their topology, we present a short tour and some history about the fossils found throughout its territory. And finally, we argue about how the fossils and the museum education could be used to prepare the pupils for first contact with TENS.
Genital graft-versus-host disease (GVHD) after hematopoietic stem cell transplantation (HSCT) is an underdiagnosed manifestation of chronic GVHD. Few articles have been published in pediatric populations, and there are no established guidelines for the management of this condition in children. This study aims to provide a systematic literature review of the published studies and cases of genital (vulvovaginal) GVHD in girls and adolescents post HSCT, with a focus on the time of diagnosis and clinical manifestations. The authors searched for English-language articles published after 1990, which included full patient details. Thirty-two cases of female patients under 20 years of age were identified. The median time of diagnosis was 381 days (IQR: 226-730 days), and 83{%} of patients developed Grade 3 vulvovaginal GVHD. Based on these observations, an early pediatric gynecologic examination of these patients, soon within the first year after HSCT, could be suggested for early diagnosis, treatment initiation and prevention of long-term complications.
A new assessment method named GEOAM (geoeducational assessment method), that will be a useful tool for highlighting the geoeducational and geoethical value of a geosite, is proposed. This method takes into account, initially, 11 criteria, which are grouped into 8 categories. Each criterion addresses a different aspect of the geosite’s potential for promoting sustainable development, environmental management, and education. A simplified scoring system using a scale of 1–5 is used, where each criterion is scored based on the degree to which it is presented or implemented. The method was piloted in eight geotopes of the Kalymnos Island and five geotopes of the Nisyros Island, in the SE Aegean Sea, Greece. The implementation of this assessment method highlighted the geoeducational value of these geosites. Based on the criteria and subcriteria incorporated in GEOAM, this paper discusses GEOAM’s potential to promote sustainable development and rational environmental management by directing educators and stakeholders toward actions that conserve and protect geoheritage for future generations, while also contributing to the economic, social, and cultural development of the surrounding communities. By quantifying the geoeducational potential of geosites and integrating essential concepts such as geoconservation and geoethics, the implementation of this new assessment method can benefit the educational community, tourism industry, and environmental conservation efforts.
The geosites of Lemnos represent local touristic products that, beyond their high aesthetic value, display significant scientific links to the geological past as well as prehistory and history, archaeology, mythology and religious heritage of the island. The unique wealth of Lemnos geosites in combination with the abundance of archaeological sites, cultural monuments and museums composes the basis of what we define here as “Geo-Archaeo-Routes”: certain routes that can be geographically defined, offered, guided and finally followed by the touristic masses. The outcome of the performed quantitative Lemnos geosite assessment enables decision making, thus providing a toolbox useful for sustainable Geo-Archaeo-tourism development at a local level and forms the basis for designing “Geo-Archaeo-Routes”. “Geo-Archaeo-Routes” are particularly favorable of environmentally friendly alternative types of tourism, attracting naturalists, hikers, fans of cultural or religious tourism and many others who represent a major part of the touristic needs of the 21st century. The established hiking and road “Geo-Archaeo-Routes” on Lemnos Island may represent a distinctive touristic product as they offer a high level of “nalture” entertainment, blending “nature with culture” in the framework of a holistic geotouristic approach.
Studies of the upper 447m of the DEEP site sediment succession from central Lake Ohrid, Balkan Peninsula, North Macedonia and Albania provided important insights into the regional climate history and evolutionary dynamics since permanent lacustrine conditions established at 1.36 million years ago (Ma). This paper focuses on the entire 584-m-long DEEP sediment succession and a comparison to a 197-m-long sediment succession from the Pestani site ~5 km to the east in the lake, where drilling ended close to the bedrock, to unravel the earliest history of Lake Ohrid and its basin development. 26Al/10Be dating of clasts from the base of the DEEP sediment succession implies that the sedimentation in the modern basin started at c. 2 Ma. Geophysical, sedimentological and micropalaeontological data allow for chronological information to be transposed from the DEEP to the Pestani succession. Fluvial conditions, slack water conditions, peat formation and/or complete desiccation prevailed at the DEEP and Pestani sites until 1.36 and 1.21 Ma, respectively, before a larger lake extended over both sites. Activation of karst aquifers to the east probably by tectonic activity and a potential existence of neighbouring Lake Prespa supported filling of Lake Ohrid. The lake deepened gradually, with a relatively constant vertical displacement rate of ~0.2 mm/a-1 between the central and the eastern lateral basin and with greater water depth presumably during interglacial periods. Although the dynamic environment characterized by local processes and the fragmentary chronology of the basal sediment successions from both sites hamper palaeoclimatic significance prior to the existence of a larger lake, the new data provide an unprecedented and detailed picture of the geodynamic evolution of the basin and lake that is Europe's presumed oldest extant freshwater lake.
The study area of Rodafnidia on the island of Lesbos (Greece) is considered of archaeological interest, as Paleolithic stone tools have been recovered through excavation and collected from the ground surface in recent years. Geologically, the area is mostly covered by Quaternary post-alpine deposits and volcanic rocks. This paper presents the application of a local geophysical survey to determine the volume of the upper Quaternary deposits in which the Paleolithic artefacts can be found and the identification of their ignimbrite substrates. For this reason, the geoelectrical method was selected as the most appropriate for determining the lithostratigraphic subsurface layers. More specifically, a grid of twenty-one (21) Vertical Electrical Soundings (VES) along with an Electrical Resistivity Tomography (ERT) was carried out. The interpretation of the results of these surveys, in conjunction with the results of older excavation trenches, revealed that the Quaternary deposits have been investigated at depths ranging from 0.5 up to 28.5 meters. Furthermore, the lithological boundary of these post-alpine deposits and their underlying pyroclastic ignimbrite flow (with resistivity 24.0–58.0 Ohm.m) seem to dip to the north. The volume of the Quaternary layer is proposed as the maximum depth for archaeological investigation with high chances to recover more Paleolithic material.
Στο άρθρο διερευνάται η δυνατότητα μιας αφηγηματικής ερευνητικής προσέγγισης να αξιολογεί με επιστημονικό τρόπο τα αποτελέσματα της εκπαίδευσης υποψηφίων εκπαιδευτικών σε ένα πρόγραμμα Πρακτικής Άσκησης. Η έρευνα ήταν ποιοτική και πραγματοποιήθηκε την ακαδημαϊκή χρονιά 2021-2022 σε δύο φάσεις. Συμμετείχαν 73 φοιτητές/τριες από το Τμήμα Θεολογίας, του Εθνικού και Καποδιστριακού Πανεπιστημίου Αθηνών, στο πλαίσιο εφαρμογής του ετήσιου προγράμματος Πρακτικής Άσκησης. Μελετήθηκαν τα αποτελέσματα που έχει η Πρακτική Άσκηση υποψηφίων εκπαιδευτικών σε σχολικό περιβάλλον, όταν αυτή πραγματοποιείται μέσω εξατομικευμένης καθοδήγησης και εποπτείας (mentoring), και εξετάστηκε η χρήση μιας αφηγηματικής ερευνητικής προσέγγισης, της τεχνικής της «πιο σημαντικής αλλαγής» (Most significant change), στην αξιολόγηση των αποτελεσμάτων της εκπαίδευσής τους. Τόσο η συλλογή όσο και η ανάλυση των δεδομένων πραγματοποιήθηκαν σε δύο χρονικές φάσεις στη διάρκεια του προγράμματος, με αξιοποίηση της θεωρητικής βάσης της συγκεκριμένης τεχνικής. Συγκεκριμένα, στο μέσο και στο τέλος της Πρακτικής Άσκησης ζητήθηκε από τους/τις φοιτητές/τριες να καταγράψουν την πιο σημαντική αλλαγή που είχαν βιώσει προσωπικά μέσα από την εμπειρία της Πρακτικής Άσκησης, ενώ στη συνέχεια διενεργήθηκε ανάλυση όλων των αφηγήσεων των αλλαγών με τη συμβολή ανεξάρτητων κριτών, ξεχωριστά για κάθε μία από τις δύο φάσεις της ερευνητικής διαδικασίας. Από την ανάλυση περιεχομένου των δεδομένων προκύπτει ότι τα αποτελέσματα από την Πρακτική Άσκηση των υποψηφίων εκπαιδευτικών σχετίζονται με το ακαδημαϊκό κομμάτι της διδασκαλίας και τη θεωρία της, ενώ ταυτόχρονα προκύπτουν αποτελέσματα που συνδέονται με τη διαμόρφωση εκπαιδευτικής επαγγελματικής ταυτότητας. Η έρευνα επιβεβαιώνει την επιστημονική αξιοπιστία της χρήσης αφηγηματικών ερευνητικών προσεγγίσεων (τεχνική της πιο σημαντικής αλλαγής) στην αξιολόγηση των αποτελεσμάτων μιας παρόμοιας εκπαιδευτικής παρέμβασης, ενώ αναδεικνύει σημαντικά κριτήρια για τον μελλοντικό σχεδιασμό προγραμμάτων Πρακτικής Άσκησης, με σκοπό την εκπαίδευση φοιτητών/τριών και υποψηφίων εκπαιδευτικών.
This work presents and discusses chapter two of Marc Lavoie’s book Post-Keynesian Economics: New Foundations. It begins by analysing the concepts of uncertainty and rationality which are extremely important for the post Keynesian approach, and for economic theorizing in general. The notions of fundamental uncertainty and the closely related concept of procedural rationality, are employed in order to build the foundations of a theory of household choice. It proceeds by investigating the repercussions of the theory in a lexicographic/hierarchical analytical framework. In this framework, groups consume different goods depending on their respective needs, income effects are more important than substitution effects, and price competition has a secondary role. It is also shown that Lavoie’s approach does not only draw from the work of Keynes and other major post-Keynesian theorists, but also utilizes contributions from other strands of heterodox economics, thus providing an agenda for a possible theoretical synthesis.
Blazars are a rare class of active galactic nuclei (AGNs) with relativistic jets pointing towards the observer. Jets are thought to be launched as Poynting-flux dominated outflows that accelerate to relativistic speeds at the expense of the available magnetic energy. In this work, we consider electron-proton jets and assume that particles are energized via magnetic reconnection in parts of the jet where the magnetization is still high (σ ≥ 1). The magnetization and bulk Lorentz factor Γ are related to the available jet energy per baryon as μ = Γ(1 + σ). We adopt an observationally motivated relation between Γ and the mass accretion rate into the black hole $\dot{m}$, which also controls the luminosity of external radiation fields. We numerically compute the photon and neutrino jet emission as a function of μ and σ. We find that the blazar SED is produced by synchrotron and inverse Compton radiation of accelerated electrons, while the emission of hadronic-related processes is subdominant except for the highest magnetization considered. We show that low-luminosity blazars (Lγ ≲ 1045 erg s-1) are associated with less powerful, slower jets with higher magnetizations in the jet dissipation region. Their broad-band photon spectra resemble those of BL Lac objects, and the expected neutrino luminosity is $L_{\nu +\bar{\nu }}\sim (0.3-1)\, L_{\gamma }$. High-luminosity blazars (Lγ ≫ 1045 erg s-1) are associated with more powerful, faster jets with lower magnetizations. Their broad-band photon spectra resemble those of flat spectrum radio quasars, and they are expected to be dim neutrino sources with $L_{\nu +\bar{\nu }}\ll L_{\gamma }$.
Relativistic hadronic plasmas can become, under certain conditions, supercritical, abruptly and efficiently releasing the energy stored in protons through photon outbursts. Past studies have tried to relate the features of such hadronic supercriticalities (HSCs) to the phenomenology of gamma-ray burst (GRB) prompt emission. In this work we investigate, for the first time, HSC in adiabatically expanding sources. We examine the conditions required to trigger HSC, study the role of expansion velocity, and discuss our results in relation to GRB prompt emission. We find multipulse light curves from slowly expanding regions (≲ 0.01c) that are a manifestation of the natural HSC quasi-periodicity, while single-pulse light curves with a fast rise and slow decay are found for higher velocities. The formation of the photon spectrum is governed by an in-source electromagnetic cascade. The peak photon energy is approximately $1 \cdot \frac{\Gamma }{100} \frac{1+z}{3}$ MeV for maximum proton energies $(1-10) \cdot \frac{\Gamma }{100} \frac{1+z}{3}$ PeV, while the peak γ-ray luminosities are in the range $(10^{49}-10^{52}) \cdot (\frac{\Gamma }{100})^4$ erg s-1. HSC bursts peaking in the MeV energy band are also copious neutrino emitters with peak energies $\sim 10 \cdot \frac{\Gamma }{100} \frac{1+z}{3}$ TeV and an all-flavour neutrino fluence $\sim 10~{{\ \rm per\ cent}}$ of the γ-ray one. The hypothesis that long-duration GRBs are powered by HSCs could be applied therefore only to the most luminous GRBs observed assuming bulk Lorentz factors Γ ≤ 100.
Despite the unique position of gold catalysis in contemporary organic synthesis, this area of research is notorious for requiring activators and/or additives that enable catalysis by generating cationic forms of gold catalysts. Cycloisomerization reactions occupy a significant portion of the gold-catalyzed reaction space, while they represent a diverse family of reactions that are frequently utilized in synthesis. Herein, hexafluoroisopropanol (HFIP) is shown to be a uniquely simple tool for gold-catalyzed cycloisomerizations, rendering the use of external activators obsolete and leading to highly active catalytic systems with ppm levels of catalyst loading in certain cases. HFIP assumes a dual role as a solvent and an activator, operating via the dynamic activation of the Au-Cl bond through hydrogen bonding, which initiates the catalytic cycle. This special mode of catalysis can enable efficient and scalable cyclization reactions of propargylamides and ynoic acids with simple [AuCl(L)] complexes. A thorough screening of ancillary ligands and counter anions has been performed, establishing this methodology as an alternative to elaborate ligand/catalyst design and to the use of activators. Additionally, this concept is applied in C-C bond-forming cycloisomerization reactions leading to 2H-chromenes and to the design of catalytic systems for sequential or one-pot transformations leading to activated ketoesters, a functionalized N-heterocyclic carbene (NHC) precursor salt, and a compound bearing the bioactive indole core, among others. Importantly, through mechanistic investigations, including a “snapshot” of the species of interest in the solid state, we were able to unambiguously detect the key H-bonding interaction between HFIP and the gold catalyst, shedding light on the intermolecular mode of activation that enables catalysis. In the cases examined herein, HFIP is not only an excellent solvent but also a potent activator and a valuable synthetic handle when incorporated into functional groups of products.
Accreting neutron stars (NSs) represent a unique laboratory for probing the physics of accretion in the presence of strong magnetic fields (B ≳ 108 G). Additionally, the matter inside the NS itself exists in an ultra-dense, cold state that cannot be reproduced in Earth-based laboratories. Hence, observational studies of these objects are a way to probe the most extreme physical regimes. Here we present an overview of the field and discuss the most important outstanding problems related to NS accretion. We show how these open questions regarding accreting NSs in both low-mass and high-mass X-ray binary systems can be addressed with the High-Energy X-ray Probe (HEX-P) via simulated data. In particular, with the broad X-ray passband and improved sensitivity afforded by a low X-ray background, HEX-P will be able to 1) distinguish between competing continuum emission models; 2) provide tighter upper limits on NS radii via reflection modeling techniques that are independent and complementary to other existing methods; 3) constrain magnetic field geometry, plasma parameters, and accretion column emission patterns by characterizing fundamental and harmonic cyclotron lines and exploring their behavior with pulse phase; 4) directly measure the surface magnetic field strength of highly magnetized NSs at the lowest accretion luminosities; as well as 5) detect cyclotron line features in extragalactic sources and probe their dependence on luminosity in the super-Eddington regime in order to distinguish between geometrical evolution and accretion-induced decay of the magnetic field. In these ways HEX-P will provide an essential new tool for exploring the physics of NSs, their magnetic fields, and the physics of extreme accretion.
Introduction: Ultraluminous X-ray sources (ULXs) represent an extreme class of accreting compact objects: from the identification of some of the accretors as neutron stars to the detection of powerful winds travelling at 0.1–0.2 c, the increasing evidence points towards ULXs harbouring stellar-mass compact objects undergoing highly super-Eddington accretion. Measuring their intrinsic properties, such as the accretion rate onto the compact object, the outflow rate, the masses of accretor/companion-hence their progenitors, lifetimes, and future evolution-is challenging due to ULXs being mostly extragalactic and in crowded fields. Yet ULXs represent our best opportunity to understand super-Eddington accretion physics and the paths through binary evolution to eventual double compact object binaries and gravitational-wave sources. Methods: Through a combination of end-to-end and single-source simulations, we investigate the ability of HEX-P to study ULXs in the context of their host galaxies and compare it to XMM-Newton and NuSTAR, the current instruments with the most similar capabilities.Results: HEX-P's higher sensitivity, which is driven by its narrow point-spread function and low background, allows it to detect pulsations and broad spectral features from ULXs better than XMM-Newton and NuSTAR.Discussion: We describe the value of HEX-P in understanding ULXs and their associated key physics, through a combination of broadband sensitivity, timing resolution, and angular resolution, which make the mission ideal for pulsation detection and low-background, broadband spectral studies.
The identification of multiple simultaneous orientations of small molecule inhibitors binding to a protein target is a common challenge. It has recently been reported that the conformational heterogeneity of ligands is widely underreported in the Protein Data Bank, which is likely to impede optimal exploitation to improve affinity of these ligands. Significantly less is even known about multiple binding orientations for fragments (<300 Da), although this information would be essential for subsequent fragment optimisation using growing, linking or merging and rational structure-based design. Here, we use recently reported fragment hits for the SARS-CoV-2 non-structural protein 1 (nsp1) N-terminal domain to propose a general procedure for unambiguously identifying binding orientations of 2-dimensional fragments containing either sulphur or chloro substituents within the wavelength range of most tunable beamlines. By measuring datasets at two energies, using a tunable beamline operating in vacuum and optimised for data collection at very low X-ray energies, we show that the anomalous signal can be used to identify multiple orientations in small fragments containing sulphur and/or chloro substituents or to verify recently reported conformations. Although in this specific case we identified the positions of sulphur and chlorine in fragments bound to their protein target, we are confident that this work can be further expanded to additional atoms or ions which often occur in fragments. Finally, our improvements in the understanding of binding orientations will also serve to improve the rational optimisation of SARS-CoV-2 nsp1 fragment hits.
Ouldali N, Son MBF, McArdle AJ, Vito O, Vaugon E, Belot A, Leblanc C, Murray NL, Patel MM, Levin M. Immunomodulatory therapy for MIS-C. Pediatrics. 2023;152(1):e2022061173.
Noble metal nanostructured substrates enhance photoluminescence emitted from molecules immobilized onto their surface, allowing for the development of highly sensitive immunoassays employing fluorescent labels. In this work, nanostructured silver surfaces were implemented as substrates for the immunochemical detection of two ovarian cancer markers, carbohydrate antigen 125 (CA125) and human epididymis protein 4 (HE4). Biotinylated detection antibodies were used to allow for the detection of immunocomplexes through a reaction with streptavidin conjugated to Rhodamine Red-X. The detection limits achieved were 2.5 U/mL and 0.06 ng/mL for CA125 and HE4, respectively, with linear dynamic ranges, covering the concentration ranges of both healthy and ovarian cancer patients.
HIV/HCV prevention among people who inject drugs (PWID) is of key public health importance. We aimed to assess the impact of COVID-19 and associated response measures on HIV/HCV prevention services and socio-economic status of PWID in high-HIV-risk sites. Sites with recent (2011–2019) HIV outbreaks among PWID in Europe North America and Israel, that had been previously identified, were contacted early May 2020. Out of 17 sites invited to participate, 13 accepted. Semi-structured qualitative site reports were prepared covering data from March to May 2020, analyzed/coded and confirmed with a structured questionnaire, in which all sites explicitly responded to all 103 issues reported in the qualitative reports. Opioid maintenance treatment, needle/syringe programs and antiretroviral treatment /hepatitis C treatment continued, but with important reductions and operational changes. Increases in overdoses, widespread difficulties with food and hygiene needs, disruptions in drug supply, and increased homelessness were reported. Service programs rapidly reformed long established, and politically entrenched, restrictive service delivery policies. Future epidemic control measures should include mitigation of negative side-effects on service provision and socio-economic determinants in PWID.
Despite being relatively rare, Mediterranean tropical-like cyclones, also known as Medicanes, induce significant impacts on coastal Mediterranean areas. Under climate change, it is possible that these effects will increase in frequency and severity. Currently, there is only a broad understanding of the types and mechanisms of these impacts. This work studied Medicane Ianos (September 2020) and its effects on the Ionian Islands, in Greece, by developing a database of distinct impact elements based on field surveys and public records. Through this archive, the study explored the range of Ianos’ impacts to develop a systematic categorization. Results showed different types of effects induced on the natural and the built environment that can be grouped into 3 categories and 39 sub-categories in inland and coastal areas, indicating an extensive diversity of impacts, ranging from flooding and geomorphic effects to damages in various facilities, vehicles and infrastructure. The systematic description of the typology of Medicanes’ effects presented in this study is a contribution to a better understanding of their consequences as means to improve our ability to prepare for, respond to, and recover from them, a necessary stepping stone in improving the overall preparedness of both the general public and relevant authorities.
The influence of neutrosophy on many fields of science and technology, as well as its numerous applications, are evident. Our motivation is to apply neutrosophy for the first time in order to improve methods for solving unconstrained optimization. Particularly, in this research, we propose and investigate an improvement of line search methods for solving unconstrained nonlinear optimization models. The improvement is based on the application of symmetry involved in neutrosophic logic in determining appropriate step size for the class of descent direction methods. Theoretical analysis is performed to show the convergence of proposed iterations under the same conditions as for the related standard iterations. Mutual comparison and analysis of generated numerical results reveal better behavior of the suggested iterations compared with analogous available iterations considering the Dolan and Moré performance profiles and statistical ranking. Statistical comparison also reveals advantages of the neutrosophic improvements of the considered line search optimization methods.
This paper presents the methodology of an applied geophysical and remote sensing research at river deltas for their subsurface and surface structure and its application in the deltaic plain of Pineios River (Thessaly, Greece). The scope is to primarily calculate the thickness of deltaic post alpine deposits, with the contribution of Transient Electromagnetic Method (TEM), but also identify the surficial characteristics (biotic/ abiotic) of the area with the appropriate combination of spectral bands and spectral indices. Regarding the remote sensing approach, some geomorphological features were outlined. This was managed from six false color composites of the area, produced by combining spectral bands and additional five false color composites by combining several spectral indices. •The results of the TEM method along with their statistical analysis provided important information regarding the spatial distribution and thickness of the lithological units along the deltaic plain.•The combination of spectral bands 8, 7, 6 seems to adumbrate the hydrographic network of the area and even detects possible changes in the inflow.•The combination of spectral indices MSAVI2, WV-BI, WV-WI was helpful enough to geomorphological mapping of the deltaic plain.
This paper presents the methodology of an applied geophysical and remote sensing research at river deltas for their subsurface and surface structure and its application in the deltaic plain of Pineios River (Thessaly, Greece). The scope is to primarily calculate the thickness of deltaic post alpine deposits, with the contribution of Transient Electromagnetic Method (TEM), but also identify the surficial characteristics (biotic/ abiotic) of the area with the appropriate combination of spectral bands and spectral indices. Regarding the remote sensing approach, some geomorphological features were outlined. This was managed from six false color composites of the area, produced by combining spectral bands and additional five false color composites by combining several spectral indices. • The results of the TEM method along with their statistical analysis provided important information regarding the spatial distribution and thickness of the lithological units along the deltaic plain • The combination of spectral bands 8, 7, 6 seems to adumbrate the hydrographic network of the area and even detects possible changes in the inflow. • The combination of spectral indices MSAVI2, WV-BI, WV-WI was helpful enough to geomorphological mapping of the deltaic plain.
The dynamics of fluid flows give rise to robust, persistent circulation features that underpin the flow and exert strong control over the advection of water masses, either enhancing it or suppressing it, collectively known as lagrangian coherent structures. Lagrangian approaches and metrics have been shown to be better suited than eulerian ones at locating and delineating such structures and capturing the effect they have on the formation and dispersion of water masses, particularly at the smaller scales. In this paper, we use the framework of lagrangian coherent structures to analyse the ocean velocity fields over a climatological year obtained from a high-resolution eddy-resolving model in order to investigate the lagrangian regimes that affect the motion, separation and mixing of water masses in the Mediterranean Sea. The lagrangian regimes that develop in each sub-basin over the course of the year are characterised and regions of persistent lagrangian activity and coherent structure formation and presence are identified. A quantitative picture of the seasonal variability of the lagrangian coherent structure-induced horizontal mixing and vortex formation is obtained.
The dynamics of fluid flows give rise to robust, persistent circulation features that underpin the flow and exert strong control over the advection of water masses, either enhancing it or suppressing it, collectively known as lagrangian coherent structures. Lagrangian approaches and metrics have been shown to be better suited than eulerian ones at locating and delineating such structures and capturing the effect they have on the formation and dispersion of water masses, particularly at the smaller scales. In this paper, we use the framework of lagrangian coherent structures to analyse the ocean velocity fields over a climatological year obtained from a high-resolution eddy-resolving model in order to investigate the lagrangian regimes that affect the motion, separation and mixing of water masses in the Mediterranean Sea. The lagrangian regimes that develop in each sub-basin over the course of the year are characterised and regions of persistent lagrangian activity and coherent structure formation and presence are identified. A quantitative picture of the seasonal variability of the lagrangian coherent structure-induced horizontal mixing and vortex formation is obtained.
This paper proposes the utilization of large language models as recommendation systems for museum visitors. Since the aforementioned models lack the notion of context, they cannot work with temporal information that is often present in recommendations for cultural environments (e.g., special exhibitions or events). In this respect, the current work aims to enhance the capabilities of large language models through a fine-tuning process that incorporates contextual information and user instructions. The resulting models are expected to be capable of providing personalized recommendations that are aligned with user preferences and desires. More specifically, Generative Pre-trained Transformer 4, a knowledge-based large language model is fine-tuned and turned into a context-aware recommendation system, adapting its suggestions based on user input and specific contextual factors such as location, time of visit, and other relevant parameters. The effectiveness of the proposed approach is evaluated through certain user studies, which ensure an improved user experience and engagement within the museum environment.
We present here the first long Quaternary record of organic-walled dinoflagellate cyst assemblages analysed from sediment cores retrieved during the International Ocean Discovery Program (IODP) Expedition 381 in the Gulf of Corinth. Site M0078A is located in the central part of the Gulf of Corinth (GoC), a semi-isolated marine basin that was repeatedly isolated and reconnected to the Mediterranean Sea during the Quaternary glacial/interglacial cycles. Our results show that dinoflagellate cysts are sorted in two major ecogroups, each group alternating between marine and isolated/brackish conditions. The marine intervals are characterised by high dinocyst diversity whereas the isolated intervals are dominated by taxa thriving in low-salinity conditions such as Spiniferites cruciformis and Pyxidinopsis psilata. In several of these assemblages, S. cruciformis is so prevalent that it forms almost monospecific assemblages. The low salinity dinocyst assemblages are reported for the first time outside the Ponto-Caspian region and they show a close affinity to modern assemblages from the Black Sea, Caspian Sea and Marmara Sea. The alternations between marine and brackish conditions recorded in the Gulf of Corinth reflect changes in surface water salinity (SSS) and temperature (SST), in response to the Quaternary glacial-interglacial cycles. These seem to be in good agreement with regional and global marine isotope and sea-level records. Our findings suggest that the study region sensitively responds to climate forcing at orbital time scales and that local factors most likely drive shifts in dinoflagellate species composition and diversity.
À travers l’étude du système à effet intégrateur de rituels et de cérémonialscélébrant la présidente de l’UFF et de la FDIF Eugénie Cotton, promue en autorité universelle dont les vertus renvoient au modèle marial, le présent travail explore la mise en place dans le monde communiste de la guerre froide du versant féminin du culte du leader. Afin d’en saisir les spécificités par rapport à un phénomène historique dont la riche production historiographique des vingt dernières années consacre naturellement et exclusivement la masculinité, y sont examinés plus particulièrement les circonstances qui lui donnèrent naissance, les temps forts qui scandent son cheminement, les mécanismes de sa diffusion et les glissements genrés opérés dans le processus de son invention." The communist cult of the female leader: Eugénie Cotton (1881-1967), “world mother” "This article considers the rituals and ceremonies celebrating the French pro-communist activist, Eugénie Cotton, president of the Union of French Women (UFW) and of the Women’s International Democratic Federation (WIDF), and the way Cotton was elevated to the rank of universal authority, exemplifying virtues not unrelated to the model of the Virgin Mary. This exploration of the enactment of the female version of the cult of the leader in the communist world during the Cold War contrasts with the masculine focus of the substantial historiographical production of the last twenty years on this topic. The paper examines in particular the circumstances that gave birth to the “Cotton cult”, the key moments in its evolution, the mechanisms of its diffusion and the gender shifts in the process of its invention.
Mots-clés : Eugénie Cotton, culte du leader, UFF, FDIF, pacifisme,guerre froideKeywords: Eugénie Cotton, cult of the leader, UFW, WIDF, pacifism,Cold War
Vasileiou P, Mertzimekis TJ, Efstathiou M, Zyriliou A, Karadimas A, Chalil A, Koseoglou P, Bonatsos D, Martinou A, Mihai C, et al.Lifetime investigations in the A 120 region. 2023.
Vasileiou P, Mertzimekis TJ, Efstathiou M, Zyriliou A, Karadimas A, Chalil A, Koseoglou P, Bonatsos D, Martinou A, Mihai C, et al.Lifetime investigations in the A 120 region. 2023.
A proper generalization of the extended boundary condition method to calculate the transition matrix, T, for electromagnetic scattering from a homogeneous and isotropic body of arbitrary shape, characterized by a periodically time-varying electric permittivity, is presented. The application of the method on a specific example of a spheroidal dielectric particle confirms that time modulation induces strong inelastic scattering, accompanied by energy transfer between the scatterer and the light field, when the difference of the incident wave frequency to a particle optical resonance matches an integer multiple of the modulation frequency. Moreover, it is shown that, for nonspherical scatterers, these effects can be selectively tuned by external means such as the polarization and the propagation direction of the incident light beam. The method is readily implementable in available dynamic multiple-scattering computer codes, and, because of its versatility and computational efficiency, it can offer new opportunities for studying more complex time-varying photonic structures.
The stability of astrophysical jets in the linear regime is investigated by presenting a methodology to find the growth rates of the various instabilities. We perturb a cylindrical axisymmetric steady jet, linearize the relativistic ideal magnetohydrodynamic (MHD) equations, and analyze the evolution of the eigenmodes of the perturbation by deriving the differential equations that need to be integrated, subject to the appropriate boundary conditions, in order to find the dispersion relation. We also apply the WKBJ approximation and, additionally, give analytical solutions in some subcases corresponding to unperturbed jets with constant bulk velocity along the symmetry axis.
Aims: We study the stability properties of relativistic magnetized astrophysical jets in the linear regime. We consider cylindrical cold jet configurations with constant Lorentz factor and constant density profiles across the jet. We are interested in probing the properties of the instabilities and identifying the physical quantities that affect the stability profile of the outflows. Methods: We conducted a linear stability analysis on the unperturbed outflow configurations we are interested in. We focus on the unstable branches, which can disrupt the initial outflow. We proceeded with a parametric study regarding the Lorentz factor, the ratio of the rest mass density of the jet to that of the environment, the magnetization, and the ratio of the poloidal component of the magnetic field to its toroidal counterpart measured on the boundary of the jet. We also consider two choices for the pressure of the environment, either thermal or magnetic, and check if this choice affects the results. Additionally, we applied a WKBJ method at the radius of the jet in order to study the local stability properties. Finally, we adapted the jet configuration in Cartesian geometry and compared the planar flow results with the results of the cylindrical counterpart. Results: While investigating the stability properties of the configurations, we observed the existence of a specific solution branch, which showcases the growth timescale of the instability comparable to the light crossing time of the jet radius. Our analysis focuses on this solution. All of the quantities considered for the parametric study affect the behavior of the mode while the magnetized environments seem to hinder its development compared to the hydrodynamic equivalent. Also, our analysis of the eigenfunctions of the system alongside the WKBJ results show that the mode develops in a very narrow layer near the boundary of the jet, establishing the notion of locality for the specific solution. The results indicate that the mode is a relativistic generalization of the Kelvin-Helmholtz instability. We compare this mode with the corresponding solution in Cartesian geometry and define the prerequisites for the Cartesian Kelvin-Helmholtz to successfully approximate the cylindrical counterpart. Conclusions: We identify the Kelvin-Helmholtz instability for a cold nonrotating relativistic jet carrying a helical magnetic field. Our parametric study reveals the important physical quantities that affect the stability profile of the outflow and their respective value ranges for which the instability is active. The Kelvin-Helmholtz mode and its stability properties are characterized by the locality of the solutions, the value of the angle between the magnetic field and the wavevector, the linear dependence between the mode's growth rate and the wavevector, and finally the stabilization of the mode for flows that are ultrafast magnetosonic. The cylindrical mode can be approximated successfully by the Cartesian Kelvin-Helmholtz instability whenever certain length scales are much larger than the jet radius.
Although the psychoanalytic theories of Heinz Kohut and Otto F. Kernberg have not explicitly focused on loneliness, they have the potential to offer a rich conceptualization of this experience in severe personality pathology. In this study, we attempt to illustrate and discuss the various qualities of loneliness in narcissistic, borderline, and other personality pathology, as implied in these theories. Kohut’s views on selfobjects are presented and the links between selfobjects and loneliness are highlighted. In this theory, loneliness may be regarded as grandiose isolation and object hunger may be viewed as a type of quasi, but not real loneliness. In Kernberg’s theory, emptiness seems to be the essence of loneliness, but it takes on different qualities in several personality disorders. Mature love is proposed as the opposite of loneliness. After identifying some points of convergence between Kohut and Kernberg regarding loneliness, we conclude with the view that real loneliness can be experienced only when genuine intimacy and mature dependence have been established.
We present a detailed compilation and analysis of the X-ray phase space of low- to intermediate-redshift (0 ≤ z ≤ 1) transients that consolidates observed light curves (and theory where necessary) for a large variety of classes of transient/variable phenomena in the 0.3-10 keV energy band. We include gamma-ray burst afterglows, supernovae, supernova shock breakouts and shocks interacting with the environment, tidal disruption events and active galactic nuclei, fast blue optical transients, cataclysmic variables, magnetar flares/outbursts and fast radio bursts, cool stellar flares, X-ray binary outbursts, and ultraluminous X-ray sources. Our overarching goal is to offer a comprehensive resource for the examination of these ephemeral events, extending the X-ray duration-luminosity phase space (DLPS) to show luminosity evolution. We use existing observations (both targeted and serendipitous) to characterize the behavior of various transient/variable populations. Contextualizing transient signals in the larger DLPS serves two primary purposes: to identify areas of interest (i.e., regions in the parameter space where one would expect detections, but in which observations have historically been lacking), and to provide initial qualitative guidance in classifying newly discovered transient signals. We find that while the most luminous (largely extragalactic) and least luminous (largely Galactic) part of the phase space is well populated at t > 0.1 days, intermediate-luminosity phenomena (L X = 1034-1042 erg s-1) represent a gap in the phase space. We thus identify L X = 1034-1042 erg s-1 and t = 10-4 to 0.1 days as a key discovery phase space in transient X-ray astronomy.
Wine quality and typicity are complex concepts that can be hard to define. Wine is a product destined to not only be consumed and appreciated but also marketed, and its distinctiveness, quality and typicity are important characteristics that describe a wine’s sensory profile and, ultimately, add value to the finished product. Even though both quality and typicity are mostly assessed using a sensory evaluation, many studies have examined the feasibility of using chemical analysis methods in order to increase the objectivity of assessments. Today, the use of chemometrics facilitates the handling of big data, and outcomes from various analytical techniques can be integrated to produce more accurate results. This study discusses the existing sensory and analytical approaches, implications and future prospects for an objective measurement of quality and typicity as well as methods for the selection of appropriate data for predictive model development.
Microbial desulfurization has been extensively studied as a promising alternative to the widely applied chemical desulfurization process. Sulfur removal from petroleum and its products becomes essential, as the environmental regulations become increasingly stringent. Rhodococcus qingshengii IGTS8 has gained ground as a naturally occurring model biocatalyst, due to its superior specific activity for desulfurization of dibenzothiophene (DBT). Recalcitrant organic sulfur compounds—DBT included—are preferentially removed by selective carbon-sulfur bond cleavage to avoid a reduction in the calorific value of the fuel. The process, however, still has not reached economically sustainable levels, as certain limitations have been identified. One of those bottlenecks is the repression of catalytic activity caused by ubiquitous sulfur sources such as inorganic sulfate, methionine, or cysteine. Herein, we report an optimized culture medium for wild-type stain IGTS8 that completely alleviates the sulfate-mediated repression of biodesulfurization activity without modification of the natural biocatalyst. Medium C not only promotes growth in the presence of several sulfur sources, including DBT, but also enhances biodesulfurization of resting cells grown in the presence of up to 5 mM sulfate. Based on the above, the present work can be considered as a step towards the development of a more viable commercial biodesulfurization process.
Research shows that, while exposure to English as a lingua franca (ELF) discourse and to discussion of ELF-related interactional strategies – such as rephrasing, paraphrasing and translanguaging – can help raise English language teachers’ and learners’ ELF awareness, this is often not enough nor is the value of such exposure adequately monitored. In this paper, following the principles of ELF awareness (Sifakis, Nicos. 2019. ELF awareness in English language teaching: Processes and practices. Applied Linguistics 40(2). 288–306), I suggest that raising teachers’ and learners’ awareness of and attitudes towards their own experience as users of English inside and outside of the classroom needs to be prioritised, especially in Expanding Circle teaching and learning contexts. Together with this awareness, teachers and learners need to be made fully conscious of their deeper perceptions about key ELF concerns, such as the role of the native speaker in ELF interactions, the nature of intercultural communication, etc. Such awareness can be raised through metalinguistic and metacognitive activities and questions added to existing activities/materials. To this end, I propose a framework and a series of specific step-by-step scenarios and tools for raising teachers’ and learners’ ELF awareness along these lines and present four examples of integrating such metacognitive and metalinguistic activities with those of a specific textbook.
Despite significant advancements in multiple myeloma (MM) therapy, the highly heterogenous treatment response hinders reliable prognosis and tailored therapeutics. Herein, we have studied the clinical utility of miRNAs in ameliorating patients’ management.
The main aim of this study is to model the Nature-based solution of Green Roofs (GRs) in order to assess their efficiency as a mitigation strategy for UHI effects and extreme summertime temperatures over Attica in Greece. The area of study is a region that encompasses Athens, the largest Metropolitan area of Greece, and the suburbs. The analysis has been performed with the use of an advanced modeling system that consists of the mesoscale Weather Research and Forecasting model (WRF) and the advanced multilayer urban canopy scheme building energy parameter and building energy model (BEP/BEM). The two modules are fully coupled, forming WRF urban. For a better description of the urban environment and in order to use the full capabilities of the urban canopy scheme, 11 urban classes corresponding to the WUDAPT Local Climate Zones (LCZ) were used instead of the 3 traditional urban classes that the default version uses. Sensitivity tests for a major heatwave that affected the area of study have been performed in order to evaluate the impact of GRs on the UHI structure. Results indicate that the modification of the roof energy budget decreased the maximum temperature during heatwaves and altered the spatio-temporal pattern of the effect.
In the present paper, a manufacturing cell in the presence of faults, coming from the devices of the process, is considered. The modular modeling of the subsystems of the cell is accomplished using of appropriate finite deterministic automata. The desired functionality of the cell as well as appropriate safety specifications are formulated as eleven desired languages. The desired languages are expressed as regular expressions in analytic forms. The languages are realized in the form of appropriate general type supervisor forms. Using these forms, a modular supervisory design scheme is accomplished providing satisfactory performance in the presence of faults as well guaranteeing the safety requirements. The aim of the present supervisor control scheme is to achieve tolerance of basic characteristics of the process coordination to upper-level faults, despite the presence of low-level faults in the devices of the process. The complexity of the supervisor scheme is computed.
For a subpopulation of energetic gamma-ray bursts (GRBs), a moderate baryonic loading may suffice to power ultra-high-energy cosmic rays (UHECRs). Motivated by this, we study the radiative signatures of cosmic-ray protons in the prompt phase of energetic GRBs. Our framework is the internal shock model with multicollision descriptions of the relativistic ejecta (with different emission regions along the jet), plus time-dependent calculations of photon and neutrino spectra. Our GRB prototypes are motivated by Fermi-Large Area Telescope-detected GRBs (including GRB 221009A) for which further, owing to the large energy flux, neutrino nonobservation of single events may pose a strong limit on the baryonic loading. We study the feedback of protons on electromagnetic spectra in synchrotron- and inverse Compton-dominated scenarios to identify the multiwavelength signatures, to constrain the maximally allowed baryonic loading, and to point out the differences between hadronic and inverse Compton signatures. We find that hadronic signatures appear as correlated flux increases in the optical-UV to soft X-ray and GeV-TeV gamma-ray ranges in the synchrotron scenarios, whereas they are difficult to identify in inverse Compton-dominated scenarios. We demonstrate that baryonic loadings around 10, which satisfy the UHECR energetic requirements, do not distort the predicted photon spectra in the Fermi Gamma-Ray Burst Monitor range and are consistent with constraints from neutrino data if the collision radii are large enough (i.e., the time variability is not too short). It therefore seems plausible that under the condition of large dissipation radii a population of energetic GRBs can be the origin of the UHECRs.
We present a multi-messenger model for the prompt emission from GRB 221009A within the internal shock scenario. We consider the time-dependent evolution of the outflow with its impact on the observed light curve from multiple collisions, as well as the self-consistent generation of the electromagnetic spectrum in synchrotron and inverse Compton-dominated scenarios. Our lepto-hadronic model includes UHE protons potentially accelerated in the outflow, and their feedback on spectral energy distribution and on the neutrino emission. We find that we can roughly reproduce the observed light curves with an engine with varying ejection velocity of ultrarelativistic material, which has an intermediate quiescent period of about 200 s and a variability timescale of ~1 s. We consider baryonic loadings of 3 and 30 that are compatible with the hypothesis that the highest-energetic LHAASO photons might come from UHECR interactions with the extragalactic background light, and the paradigm that energetic GRBs may power the UHECR flux. For these values and the high dissipation radii considered, we find consistency with the nonobservation of neutrinos and no significant signatures on the electromagnetic spectrum. Inverse Compton-dominated scenarios from the prompt emission are demonstrated to lead to about an order of magnitude higher fluxes in the HE range; this enhancement is testable via its spectral impact in the Fermi-GBM and LAT ranges.
The blazar PKS 0735+178 is possibly associated with multiple neutrino events observed by the IceCube, Baikal, Baksan, and KM3NeT neutrino telescopes while it was flaring in the γ-ray, X-ray, ultraviolet, and optical bands. We present a detailed study of this peculiar blazar to investigate the temporal and spectral changes in the multiwavelength emission when the neutrino events were observed. The analysis of Swift-XRT snapshots reveal a flux variability of more than a factor 2 in about 5 × 103 s during the observation on 2021 December 17. In the γ-ray band, the source was in its historical highest flux level at the time of the arrival of the neutrinos. The observational comparison between PKS 0735+178 and other neutrino source candidates, such as TXS 0506+056, PKS 1424+240, and GB6 J1542+6129, shows that all these sources share similar spectral energy distributions, very high radio and γ-ray powers, and parsec scale jet properties. Moreover, we present strong supporting evidence for PKS 0735+178 to be, like all the others, a masquerading BL Lac. We perform comprehensive modelling of the multiwavelength emission from PKS 0735+178 within one-zone lepto-hadronic models considering both internal and external photon fields and estimate the expected accompanying neutrino flux. The most optimistic scenario invokes a jet with luminosity close to the Eddington value and the interactions of ~ PeV protons with an external UV photon field. This scenario predicts ~0.067 muon and anti-muon neutrinos over the observed 3-week flare. Our results are consistent with the detection of one very high-energy neutrino like IceCube-211208A.
Nature-based solutions (NbS) can be beneficial to help human communities build resilience to climate change by managing and mitigating related hydro-meteorological hazards (HMHs). Substantial research has been carried out in the past on the detection and assessment of HMHs and their derived risks. Yet, knowledge on the performance and functioning of NbS to address these hazards is severely lacking. The latter is exacerbated by the lack of practical and viable approaches that would help identify and select NbS for specific problems. The EU-funded OPERANDUM project established seven Open-Air Laboratories (OALs) across Europe to co-develop, test, and generate an evidence base from innovative NbS deployed to address HMHs such as flooding, droughts, landslides, erosion, and eutrophication. Herein, we detail the original approaches that each OAL followed in the process of identifying and selecting NbS for specific hazards with the aim of proposing a novel, generic framework for selecting NbS. We found that the process of selecting NBS was overall complex and context-specific in all the OALs, and it comprised 26 steps distributed across three stages: (i) Problem recognition, (ii) NbS identification, and (iii) NbS selection. We also identified over 20 selection criteria which, in most cases, were shared across OALs and were chiefly related to sustainability aspects. All the identified NbS were related to the regulation of the water cycle, and they were mostly chosen according to three main factors: (i) hazard type, (ii) hazard scale, and (iii) OAL size. We noticed that OALs exposed to landslides and erosion selected NbS capable to manage water budgets within the soil compartment at the local or landscape scale, while OALs exposed to floods, droughts, and eutrophication selected approaches to managing water transport and storage at the catchment scale. We successfully portrayed a synthesis of the stages and steps followed in the OALs’ NbS selection process in a framework. The framework, which reflects the experiences of the stakeholders involved, is inclusive and integrated, and it can serve as a basis to inform NbS selection processes whilst facilitating the organisation of diverse stakeholders working towards finding solutions to natural hazards. We animate the future development of the proposed framework by integrating financial viability steps. We also encourage studies looking into the implementation of the proposed framework through quantitative approaches integrating multi-criteria analyses.
Background Multiple HIV outbreaks have been recorded among people who inject drugs (PWID) since 2010. During an intervention for PWID in 2019–2021 in Thessaloniki, Greece, an increasing number of HIV cases was documented. Here, we provide an analysis of this new outbreak. Methods ALEXANDROS was a community-based program and participation included interviewing, rapid HIV/HCV tests, counselling and linkage to care. PWID were recruited through Respondent-Driven Sampling (RDS) in five sampling rounds. Crude and RDS-weighted HIV prevalence estimates were obtained. HIV incidence was estimated from data on 380 initially seronegative PWID with at least two tests. Multivariable Cox proportional hazards model was used to assess risk factors for HIV seroconversion. Results In total, 1,101 PWID were recruited. At first participation, 53.7% were current PWID, 20.1% homeless, 20.3% on opioid substitution treatment and 4.8% had received syringes in the past 12 months. HIV prevalence (95% CI) was 7.0% (5.6–8.7%) and an increasing trend was observed over 2019–2021 (p = 0.002). Two-thirds of the cases (67.5%) were new diagnoses. HIV incidence was 7.0 new infections/100 person-years (95% CI:4.8–10.2). Homelessness in the past 12 months (HR:2.68; 95% CI:1.24–5.81) and receptive syringe sharing (HR:3.86; 95% CI:1.75–8.51) were independently associated with increased risk of seroconversion. By the end of the program, 67.3% of the newly diagnosed cases initiated antiretroviral treatment. Conclusions A new HIV outbreak among PWID was documented in Greece during the COVID-19 pandemic with homelessness and syringe sharing being associated with increased risk of HIV acquisition. Peer-driven programs targeting the population of high-risk underserved PWID can be used to early identify emerging outbreaks and to improve linkage to HIV care.
Disruption in neurogenesis and neuronal migration can influence the assembly of cortical circuits, affecting the excitatory-inhibitory balance and resulting in neurodevelopmental and neuropsychiatric disorders. Using ventral cerebral organoids and dorsoventral cerebral assembloids with mutations in the extracellular matrix gene LGALS3BP, we show that extracellular vesicles released into the extracellular environment regulate the molecular differentiation of neurons, resulting in alterations in migratory dynamics. To investigate how extracellular vesicles affect neuronal specification and migration dynamics, we collected extracellular vesicles from ventral cerebral organoids carrying a mutation in LGALS3BP, previously identified in individuals with cortical malformations and neuropsychiatric disorders. These results revealed differences in protein composition and changes in dorsoventral patterning. Proteins associated with cell fate decision, neuronal migration, and extracellular matrix composition were altered in mutant extracellular vesicles. Moreover, we show that treatment with extracellular vesicles changes the transcriptomic profile in neural progenitor cells. Our results indicate that neuronal molecular differentiation can be influenced by extracellular vesicles.
An improved activation function, termed extended sign-bi-power (Esbp), is proposed. An extension of the Li zeroing neural network (ELi-ZNN) based on the Esbp activation is derived to obtain the online solution of the time-varying inversion problem. A detailed theoretical analysis confirms that the new activation function accomplishes fast convergence in calculating the time-varying matrix inversion. At the same time, illustrative numerical experiments substantiate the excellent performance of the proposed activation function over the Li and tunable activation functions. Convergence properties and numerical behaviors of the proposed ELi-ZNN model are examined.
Due to its significance in science and engineering, time-varying linear matrix equation (LME) problems have received a lot of attention from scholars. It is for this reason that the issue of finding the minimum-norm least-squares solution of the time-varying quaternion LME (ML-TQ-LME) is addressed in this study. This is accomplished using the zeroing neural network (ZNN) technique, which has achieved considerable success in tackling time-varying issues. In light of that, two new ZNN models are introduced to solve the ML-TQ-LME problem for time-varying quaternion matrices of arbitrary dimension. Two simulation experiments and two practical acoustic source tracking applications show that the models function superbly.
The Markowitz model, a Nobel Prize winning model for portfolio analysis, paves the theoretical foundation in finance for modern investment. However, it remains a challenging problem in the high frequency trading (HFT) era to find a more time efficient solution for portfolio analysis, especially when considering circumstances with the dynamic fluctuation of stock prices and the desire to pursue contradictory objectives for less risk but more return. In this paper, we establish a recurrent neural network model to address this challenging problem in runtime. Rigorous theoretical analysis on the convergence and the optimality of portfolio optimization are presented. Numerical experiments are conducted based on real data from Dow Jones Industrial Average (DJIA) components and the results reveal that the proposed solution is superior to DJIA index in terms of higher investment returns and lower risks.
Importance sampling, a variant of online sampling, is often used in neural network training to improve the learning process, and, in particular, the convergence speed of the model. We study, here, the performance of a set of batch selection algorithms, namely, online sampling algorithms that process small parts of the dataset at each iteration. Convergence is accelerated through the creation of a bias towards the learning of hard samples. We first consider the baseline algorithm and investigate its performance in terms of convergence speed and generalization efficiency. The latter, however, is limited in case of poor balancing of data sets. To alleviate this shortcoming, we propose two variations of the algorithm that achieve better generalization and also manage to not undermine the convergence speed boost offered by the original algorithm. Various data transformation techniques were tested in conjunction with the proposed scheme to develop an overall training method of the model and to ensure robustness in different training environments. An experimental framework was constructed using three naturally imbalanced datasets and one artificially imbalanced one. The results assess the advantage in convergence of the extended algorithm over the vanilla one, but, mostly, show better generalization performance in imbalanced data environments.
An extension of the photonic layer multiple scattering methodology to dynamic spherical scatterers, which exhibit a periodic time-varying response, is presented. The applicability of the method is demonstrated on specific examples of single- and bi-layers of periodically modulated high-refractive-index spherical particles arranged on a square lattice. The results provide compelling evidence for strong and tunable inelastic scattering effects under the triple resonance condition, fulfilled for optical transitions between neighboring high-Q lattice modes of the appropriate symmetry, which originate from multipolar Mie resonances. A consistent interpretation of the underlying mechanisms is provided and potential applications in the design of nonreciprocal devices are discussed.
Magnetic reconnection is often invoked as a source of high-energy particles, and in relativistic astrophysical systems it is regarded as a prime candidate for powering fast and bright flares. We present a novel analytical model-supported and benchmarked with large-scale three-dimensional kinetic particle-in-cell simulations in electron-positron plasmas-that elucidates the physics governing the generation of power-law energy spectra in relativistic reconnection. Particles with Lorentz factor γ ≳ 3σ (here, σ is the magnetization) gain most of their energy in the inflow region, while meandering between the two sides of the reconnection layer. Their acceleration time is ${t}_{\mathrm{acc}}\sim \gamma \,{\eta }_{\mathrm{rec}}^{-1}{\omega }_{{\rm{c}}}^{-1}\simeq 20\,\gamma \,{\omega }_{{\rm{c}}}^{-1}$ , where η rec ≃ 0.06 is the inflow speed in units of the speed of light and ω c = eB 0/mc is the gyrofrequency in the upstream magnetic field. They leave the region of active energization after t esc, when they get captured by one of the outflowing flux ropes of reconnected plasma. We directly measure t esc in our simulations and find that t esc ~ t acc for σ ≳ few. This leads to a universal (i.e., σ-independent) power-law spectrum ${{dN}}_{\mathrm{free}}/d\gamma \propto {\gamma }^{-1}$ for the particles undergoing active acceleration, and ${dN}/d\gamma \propto {\gamma }^{-2}$ for the overall particle population. Our results help to shed light on the ubiquitous presence of power-law particle and photon spectra in astrophysical nonthermal sources.
DNA sequences of ideal and natural geometries are examined, studying their charge transport properties as mutation detectors. Ideal means textbook geometry. Natural means naturally distorted sequences; geometry taken from available databases. A tight-binding (TB) wire model at the base-pair level is recruited, together with a transfer matrix technique. The relevant TB parameters are obtained using a linear combination of all valence orbitals of all atoms, using geometry, either ideal or natural, as the only input. The investigated DNA sequences contain: (i) point substitution mutations – specifically, the transitions guanine (G) 2 adenine (A) – and (ii) sequences extracted from human chromosomes, modified by expanding the cytosine–adenine–guanine triplet [(CAG)n repeats] to mimic the following diseases: (a) Huntington’s disease, (b) Kennedy’s disease, (c) Spinocerebellar ataxia 6, (d) Spinocerebellar ataxia 7. Quantities such as eigenspectra, density of states, transmission coefficients, and the – more experimentally relevant – current–voltage (I–V) curves are studied, intending to find adequate features to recognize mutations. To this end, the normalised deviation of the I–V curve from the origin (NDIV) is also defined. The features of the NDIV seem to provide a clearer picture, being sensitive to the number of point mutations and allowing to characterise the degree of danger of developing the aforementioned diseases.
Physics-informed neural networks (PINNs) are machine learning models that integrate data-based learning with partial differential equations (PDEs). In this work, for the first time we extend PINNs to model the numerically challenging case of astrophysical shock waves in the presence of a stellar gravitational field. Notably, PINNs suffer from competing losses during gradient descent that can lead to poor performance especially in physical setups involving multiple scales, which is the case for shocks in the gravitationally stratified solar atmosphere. We applied PINNs in three different setups ranging from modeling astrophysical shocks in cases with no or little data to data-intensive cases. Namely, we used PINNs (a) to determine the effective polytropic index controlling the heating mechanism of the space plasma within 1% error, (b) to quantitatively show that data assimilation is seamless in PINNs and small amounts of data can significantly increase the model's accuracy, and (c) to solve the forward time-dependent problem for different temporal horizons. We addressed the poor performance of PINNs through an effective normalization approach by reformulating the fluid dynamics PDE system to absorb the gravity-caused variability. This led to a huge improvement in the overall model performance with the density accuracy improving between 2 and 16 times. Finally, we present a detailed critique on the strengths and drawbacks of PINNs in tackling realistic physical problems in astrophysics and conclude that PINNs can be a powerful complimentary modeling approach to classical fluid dynamics solvers.
To date, mechanistic modeling of oral drug absorption has been achieved via the use of physiologically based pharmacokinetic (PBPK) modeling, and more specifically, physiologically based biopharmaceutics model (PBBM). The concept of finite absorption time (FAT) has been developed recently and the application of the relevant physiologically based finite time pharmacokinetic (PBFTPK) models to experimental data provides explicit evidence that drug absorption terminates at a specific time point. In this manuscript, we explored how PBBM and PBFTPK models compare when applied to the same dataset. A set of six compounds with clinical data from immediate-release formulation were selected. Both models resulted in absorption time estimates within the small intestinal transit time, with PBFTPK models generally providing shorter time estimates. A clear relationship between the absorption rate and the product of permeability and luminal concentration was observed, in concurrence with the fundamental assumptions of PBFTPK models. We propose that future research on the synergy between the two modeling approaches can lead to both improvements in the initial parameterization of PBPK/PBBM models but to also expand mechanistic oral absorption concepts to more traditional pharmacometrics applications.
The study looks at how environmental concerns were gradually elevated inside the CAP's policy-making framework and how they helped towards the “greening” transition of European agriculture. Within the context of multilevel governance, the analysis is based ontheories of policy change, primarily neo-institutionalism and historical institutionalism. Theanalysis reveals that the historical trajectory of the previous era inside the EU and the global setting is being redefined by policy change
For over a century, the identification of high-energy cosmic ray (CR) sources remains an open question. For Galactic CRs with energy up to 1015 eV, supernova remnants (SNRs) have traditionally been thought the main candidate source. However, recent TeV γ-ray observations have questioned the SNR paradigm. Propagating CRs are deflected by the Galactic magnetic field, hence, γ-rays and neutrinos produced via inelastic hadronic interactions are the only means for unveiling the CR sources. In this work, we study the γ-ray and neutrino emission produced by CRs accelerated inside Galactic jets of stellar-mass black holes in X-ray binaries (BHXBs). We calculate the intrinsic neutrino emission of two prototypical BHXBs , Cygnus X-1 and GX 339-4, for which we have high-quality, quasi-simultaneous multiwavelength spectra. Based on these prototypical sources, we discuss the likelihood of the 35 known Galactic BHXBs to be efficient CR accelerators. Moreover, we estimate the potential contribution to the CR spectrum of a viable population of BHXBs that reside in the Galactic plane. When these BHXBs go into outburst, they may accelerate particles up to hundreds of TeV that contribute to the diffuse γ-ray and neutrino spectra while propagating in the Galactic medium. Using HERMES, an open-source code that calculates the hadronic processes along the line of sight, we discuss the contribution of BHXBs to the diffuse γ-ray and neutrino fluxes, and compare these to their intrinsic γ-ray and neutrino emissions. Finally, we discuss the contribution of BHXBs to the observed spectrum of Galactic CRs.
The present study aimed to analyse the associations between spatiotemporal characteristics of the setting and the origin of the ball in terms of the game complexes for junior female volleyball teams. Multinomial logistic regression and multiple correspondence analysis were applied to analyse 3.675 setting actions (Complex I = 1.593, Complex II = 2.082) in the final phase of the Greek Junior Championship. Results showed that the origin of the ball from the left lane of the court eases the setter for an accurate setting during CI while passing from the right lane incommodes the setter during CII. Regarding setting zone, for accurate setting, odds are increased by 3.2 for zone 4 during CI while decreased by 23.8 for zone 3 during CII. The junior setters' distribution of setting is predictable and creates favourable conditions for the opponent to deal with it. The improvement of junior female setters' ability to follow the team's offensive tactic regardless of the ball's origin, to manipulate passes received from the right lane of the court during CII and the acceleration of setting tempo for the wing hitters could be training goals for coaches.
This paper examines the principles of selection and arrangement of the letters of Basil the Great in the Aldine edition and in one of the major manuscript families, arguing that the ordering of Basil’s letters in them was mainly based on the content of the letters, whether thematical or by addressee. It concludes that the ancient and medieval thematical orderings of the letters are helpful for our understanding of the content of a large collection as that of Basil, compared to the modern reconstructed chronological order presented in the editions.
The origin of extremely fast variability is one of the long-standing questions in the gamma-ray astronomy of blazars. While many models explain the slower, lower energy variability, they cannot easily account for such fast flares reaching hour-to-minute timescales. Magnetic reconnection, a process where magnetic energy is converted to the acceleration of relativistic particles in the reconnection layer, is a candidate solution to this problem. In this work, we employ state-of-the-art particle-in-cell simulations in a statistical comparison with observations of a flaring episode of a well-known blazar, Mrk 421, at a very high energy (VHE, E > 100 GeV). We tested the predictions of our model by generating simulated VHE light curves that we compared quantitatively with methods that we have developed for a precise evaluation of theoretical and observed data. With our analysis, we can constrain the parameter space of the model, such as the magnetic field strength of the unreconnected plasma, viewing angle and the reconnection layer orientation in the blazar jet. Our analysis favours parameter spaces with magnetic field strength 0.1 G, rather large viewing angles (6 − 8°), and misaligned layer angles, offering a strong candidate explanation for the Doppler crisis often observed in the jets of high synchrotron peaking blazars. Full Tables B.1-B.10 are available at the CDS via anonymous ftp to cdsarc.cds.unistra.fr (ftp://130.79.128.5) or via https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/678/A140
During the last decades, the utilization of imaging modalities such as single photon emission computed tomography (SPECT), positron emission tomography (PET), and magnetic resonance imaging (MRI) in every day clinical practice has enabled clinicians to diagnose diseases accurately at early stages. Radiolabeled iron oxide nanoparticles (RIONs) combine their intrinsic magnetic behavior with the extrinsic character of the radionuclide additive, so that they constitute a platform of multifaceted physical properties. Thus, at a practical level, RIONs serve as the physical parent of the so-called dual-modality contrast agents (DMCAs) utilized in SPECT/MRI and PET/MRI applications due to their ability to combine, at real time, the high sensitivity of SPECT or PET together with the high spatial resolution of MRI. This review focuses on the synthesis and in vivo investigation of both biodistribution and imaging efficacy of RIONs as potential SPECT/MRI or PET/MRI DMCAs.
L’adoption d’une approche apaisante similaire, indistinctement et surtout de manière déraisonnable, constitue à la fois une erreur méthodologique et scientifique inhérente, mais aussi un choix diplomatique et national, à fortiori, malheureux qui, je le crains, conduira avec une précision mathématique dans une atteinte, sans précédent et en tout cas irréversible, aux intérêts de notre « commettant » nationalcommun (j’imagine)...Du peuple grec...De l’hellénisme, en général, en Grèce, à Chypre, mais aussi de la diaspora dans son ensemble !!! (qui a récemment acquis le droit de vote, elle est donc désormais légitimée d’avoir son mot à dire dans les affaires publiques!!!
Greece is a country structured by land, several islands and sea. A regional gravity model of such a country demands the involvement of several types of gravity data in order to cover all its territory. In this paper, we present the development of a regional combined gravity model of Greece and its surroundingarea, by integrating terrestrial, marine (shipborne and altimetry-derived gravity data) and satellite data (GOCE and GRACE data). These kinds of data, especially the terrestrial and marine ones, have passed quality and validation control since they were collected from different organizations, which means that they probably have been acquired and processed with different parametersand formulas. Following that, their integration was accomplished with the application of the least-squares collocation (LSC). Therefore, a newly combined regional gravity model of Greece and its surrounding areas has been developed. This gravity model can be valuable for regional geological and geophysical studies of Greece, since it provides homogeneously the distribution of Complete Bouguer anomaly (CBA) all over Greece, with updated gravity data and in good agreement with the initial gravity datasets that have been used.
Based on fresh archival research this article examines the exchange of Romanizing statuary between Italy and Spain during the ventennio fascista. Between 1933 and 1943, Italy and Spain exchanged copies of Roman statues as symbolic gestures, to substantiate their claims to a shared classical heritage of ‘imperial greatness’. Using press reports and documentary film excerpts the article reconstructs public events that took place in Merida, Tarragona, Palma, and Zaragoza and assesses their impact. Behind these exchanges, and public ceremonies staged on their occasion, lay the Fascist concept of romanità: an archaeologically and aesthetically charged discourse placing Late-Republican and Early-Imperial Roman heritage in the epicentre of Fascist identity politics. Through improvised public performances of romanità, classical materialities, monumental as well as spatial, were imbued with Fascist dynamics, as the past turned into the present and projected into the future. Through individual and collective performance these ceremonies embodied a primeval Fascist ideal that appeared at once spectacular and modern.
Objectives In the era of precision medicine, the highly aggressive and heterogenous triple-negative breast cancer (TNBC) is still characterized by limited options to support personalized prognosis and guide therapeutic interventions. Thereafter, the aim of the present study has been the thorough evaluation of miR-146a as a novel molecular indicator of TNBC prognosis and treatment outcome, utilizing four independent TNBC cohorts. Design & methods miR-146a levels were clinically evaluated in our screening (n = 122) and three external validation TNBC cohorts (de Rinaldis et al. 2013, n = 114; Jézéquel et al. 2015, n = 107; TCGA, n = 180). Analysis of miR-146a and validated gene targets was performed in Jézéquel et al. and TCGA validation cohorts. Patients’ survival, recurrence and metastasis were determined as clinical endpoints for the survival analysis. Internal validation was performed by bootstrap analysis and clinical net benefit was evaluated by decision curve analysis. Results Reduction of miR-146a is strongly associated with patients’ poor survival and can predict post-treatment disease early-recurrence, independently of tumor size, lymph node status, histological grade and patients’ age. The analysis of the external validation cohorts corroborated the unfavorable nature of miR-146a repression regarding patients’ survival and, strikingly, unveiled the ability of miR-146a to predict TNBC metastasis. Combined assessment of miR-146a levels and lymph node status resulted in superior risk-stratification of TNBC patients and higher clinical benefit regarding disease prognosis and post-treatment outcome. Ultimately, miR-146a was negatively associated with EGFR and SOX2 expression in TNBC. Conclusions miR-146a evaluation could ameliorate personalized prognosis and support precision medicine decisions in TNBC.
Accumulation of DNA damage resulting from reactive oxygen species was proposed to cause neurological and degenerative disease in patients, deficient in nucleotide excision repair (NER) or its transcription-coupled subpathway (TC-NER). Here, we assessed the requirement of TC-NER for the repair of specific types of oxidatively generated DNA modifications. We incorporated synthetic 5′,8-cyclo-2′-deoxypurine nucleotides (cyclo-dA, cyclo-dG) and thymine glycol (Tg) into an EGFP reporter gene to measure transcription-blocking potentials of these modifications in human cells. Using null mutants, we further identified the relevant DNA repair components by a host cell reactivation approach. The results indicated that NTHL1-initiated base excision repair is by far the most efficient pathway for Tg. Moreover, Tg was efficiently bypassed during transcription, which effectively rules out TC-NER as an alternative repair mechanism. In a sharp contrast, both cyclopurine lesions robustly blocked transcription and were repaired by NER, wherein the specific TC-NER components CSB/ERCC6 and CSA/ERCC8 were as essential as XPA. Instead, repair of classical NER substrates, cyclobutane pyrimidine dimer and N-(deoxyguanosin-8-yl)-2-acetylaminofluorene, occurred even when TC-NER was disrupted. The strict requirement of TC-NER highlights cyclo-dA and cyclo-dG as candidate damage types, accountable for cytotoxic and degenerative responses in individuals affected by genetic defects in this pathway.
The core components of both traditional and contemporary control systems are the proportional–integral–derivative (PID) control systems, which have established themselves as standards for technical and industrial applications. Therefore, the tuning of the PID controllers is of high importance. Utilizing optimization algorithms to reduce the mean square error of the controller’s output is one approach of tuning PID controllers. In this paper, an appropriately modified metaheuristic optimization algorithm dubbed beetle antennae search (BAS) is employed for robust tuning of PID controllers. The findings of three simulated experiments on stabilizing feedback control systems show that BAS produces comparable or higher performance than three other well-known optimization algorithms while only consuming a tenth of their time.
Mitochondria are cellular organelles that play an essential role in generating the chemical energy needed for the biochemical reactions in cells. Mitochondrial biogenesis, i.e., de novo mitochondria formation, results in enhanced cellular respiration, metabolic processes, and ATP generation, while autophagic clearance of mitochondria (mitophagy) is required to remove damaged or useless mitochondria. The balance between the opposing processes of mitochondrial biogenesis and mitophagy is highly regulated and crucial for the maintenance of the number and function of mitochondria as well as for the cellular homeostasis and adaptations to metabolic demands and extracellular stimuli. In skeletal muscle, mitochondria are essential for maintaining energy homeostasis, and the mitochondrial network exhibits complex behaviors and undergoes dynamic remodeling in response to various conditions and pathologies characterized by changes in muscle cell structure and metabolism, such as exercise, muscle damage, and myopathies. In particular, the involvement of mitochondrial remodeling in mediating skeletal muscle regeneration following damage has received increased attention, as modifications in mitophagy-related signals arise from exercise, while variations in mitochondrial restructuring pathways can lead to partial regeneration and impaired muscle function. Muscle regeneration (through myogenesis) following exercise-induced damage is characterized by a highly regulated, rapid turnover of poor-functioning mitochondria, permitting the synthesis of better-functioning mitochondria to occur. Nevertheless, essential aspects of mitochondrial remodeling during muscle regeneration remain poorly understood and warrant further characterization. In this review, we focus on the critical role of mitophagy for proper muscle cell regeneration following damage, highlighting the molecular mechanisms of the mitophagy-associated mitochondrial dynamics and network reformation.
The chemical investigation of the organic extract of the red alga Laurencia majuscula collected from Hurghada reef in the Red Sea resulted in the isolation of five C15 acetogenins, including four tricyclic ones of the maneonene type (1–4) and a 5-membered one (5), 15 sesquiterpenes, including seven lauranes (6–12), one cuparane (13), one seco-laurane (14), one snyderane (15), two chamigranes (16, 17), two rearranged chamigranes (18, 19) and one aristolane (20), as well as a tricyclic diterpene (21) and a chlorinated fatty acid derivative (22). Among them, compounds 1–3, 5, 7, 8, 10, 11 and 14 are new natural products. The structures and the relative configurations of the isolated natural products have been established based on extensive analysis of their NMR and MS data, while the absolute configuration of maneonenes F (1) and G (2) was determined on the basis of single-crystal X-ray diffraction analysis. The anti-inflammatory activity of compounds 1, 2, 4–8, 10, 12–16, 18 and 20–22 was evaluated by measuring suppression of nitric oxide (NO) release in TLR4-activated RAW 264.7 macrophages in culture. All compounds, except 6, exhibited significant anti-inflammatory activity. Among them, metabolites 1, 4 and 18 did not exhibit any cytostatic activity at the tested concentrations. The most prominent anti-inflammatory activity, accompanied by absence of cytostatic activity at the same concentration, was exerted by compounds 5 and 18, with IC50 values of 3.69 μM and 3.55 μΜ, respectively.
In recent years, on the one hand, we have witnessed the rise of blockchain technology, which has led to better transparency, traceability, and therefore, trustworthy exchange of digital assets among different actors. On the other hand, achieving trustworthy content exchange has been one of the primary objectives of the Semantic Web, part of the World Wide Web Consortium. Semantic Web and blockchain technologies are the fundamental building blocks of Web3 (the third version of the Internet), which aims to link data through a decentralized approach. Blockchain provides a decentralized and secure framework for users to safeguard their data and take control over their data and Web3 experiences. However, developing trustworthy decentralized applications (Dapps) is a challenge because many blockchain-based functionalities must be developed from scratch, and combined with data semantics to open new innovative opportunities. In this survey paper, we explore the cross-cutting domain of the Semantic Web and blockchain and identify the critical building blocks required to achieve trust in the Next-Generation Internet. The application domains that could benefit from these technologies are also investigated. We developed a deep analysis of the published literature between 2015 and 2023. We performed our analysis in different digital libraries (e.g., Elsevier, IEEE, ACM), and as a result of our research, we retrieved 137 papers, of which 97 were retrieved as relevant to include in the paper. Furthermore, we studied several aspects (e.g., network type, transactions per second) of existing blockchain platforms. Semantic Web and blockchain technologies can be used to realize a verification and certification process for data quality. Examples of mechanisms to achieve this are the Decentralized Identities of the Semantic Web or the various blockchain consensus protocols that help achieve decentralization and realize democratic principles. Therefore, Semantic Web and blockchain technologies should be combined to achieve trust in the highly decentralized, semantically complex, and dynamic environments needed to build smart applications of the future.
Sitting volleyball (SV) is a dynamic with short actions sport in the paralympic programme. The purpose of the study was to identify the volleyball skills that best discriminate between winning and losing an SV set, for both the genders. The data were collected from all sets played (N = 224) on the 2019 European men and women SV Championship. Cluster analysis established three types of sets according to the final score difference: 2–4 points (balanced), 5–11 points (semi-balanced) and over 11 points (unbalanced). Three-way MANOVAs were conducted to analyse gender, type of set and type of result differences for selected performance indicators. The analyses revealed significant multivariate differences across gender (p <.001), types of set (p =.014) and result (p <.001) and significant interaction effect of result with gender (p =.025) and type of set (p <.001). A follow-up discriminant analysis showed that setting and attacking were the most important skills for all sets. The results showed that in SV the attack is the most important factor, which determines winners and losers, even in balanced sets. In SV, the importance of skills across gender was similar to volleyball, while there were differences in the structure of the game compared to the sequential order of skills in volleyball.
Glutathione and malondialdehyde are two compounds commonly used to evaluate the oxidative stress status of an organism. Although their determination is usually performed in blood serum, saliva is gaining ground as the biological fluid of choice for oxidative stress determination at the point of need. For this purpose, surface-enhanced Raman spectroscopy (SERS), which is a highly sensitive method for the detection of biomolecules, could offer additional advantages regarding the analysis of biological fluids at the point of need. In this work, silicon nanowires decorated with silver nanoparticles made by metal-assisted chemical etching were evaluated as substrates for the SERS determination of glutathione and malondialdehyde in water and saliva. In particular, glutathione was determined by monitoring the reduction in the Raman signal obtained from substrates modified with crystal violet upon incubation with aqueous glutathione solutions. On the other hand, malondialdehyde was detected after a reaction with thiobarbituric acid to produce a derivative with a strong Raman signal. The detection limits achieved after optimization of several assay parameters were 50 and 3.2 nM for aqueous solutions of glutathione and malondialdehyde, respectively. In artificial saliva, however, the detection limits were 2.0 and 0.32 μM for glutathione and malondialdehyde, respectively, which are, nonetheless, adequate for the determination of these two markers in saliva.
Early diagnosis and monitoring are essential for the effective treatment and survival of patients with different types of malignancy. To this end, the accurate and sensitive determination of substances in human biological fluids related to cancer diagnosis and/or prognosis, i.e., cancer biomarkers, is of ultimate importance. Advancements in the field of immunodetection and nanomaterials have enabled the application of new transduction approaches for the sensitive detection of single or multiple cancer biomarkers in biological fluids. Immunosensors based on surface-enhanced Raman spectroscopy (SERS) are examples where the special properties of nanostructured materials and immunoreagents are combined to develop analytical tools that hold promise for point-of-care applications. In this frame, the subject of this review article is to present the advancements made so far regarding the immunochemical determination of cancer biomarkers by SERS. Thus, after a short introduction about the principles of both immunoassays and SERS, an extended presentation of up-to-date works regarding both single and multi-analyte determination of cancer biomarkers is presented. Finally, future perspectives on the field of SERS immunosensors for cancer markers detection are briefly discussed.
Depression and anxiety disorders carry a tremendous worldwide burden and emerge as a significant cause of disability among western societies. Both disorders are known to disproportionally affect women, as they are twice more likely to be diagnosed and moreover, they are also prone to suffer from female-specific mood disorders. Importantly, the prevalence of these affective disorders has notably risen after the COVID pandemic, especially in women. In this chapter, we describe factors that are possibly contributing to the expression of such sex differences in depression and anxiety. For this, we overview the effect of transcriptomic and genetic factors, the immune system, neuroendocrine aspects, and cognition. Furthermore, we also provide evidence of sex differences in antidepressant response and their causes. Finally, we emphasize the importance to consider sex as a biological variable in preclinical and clinical research, which may facilitate the discovery and development of new and more efficacious antidepressant and anxiolytic pharmacotherapies for both women and men.
Accretion disks around compact objects are expected to enter an unstable phase at high luminosity1. One instability may occur when the radiation pressure generated by accretion modifies the disk viscosity, resulting in the cyclic depletion and refilling of the inner disk on short timescales2. Such a scenario, however, has only been quantitatively verified for a single stellar-mass black hole3-5. Although there are hints of these cycles in a few isolated cases6-10, their apparent absence in the variable emission of most bright accreting neutron stars and black holes has been a continuing puzzle11. Here we report the presence of the same multiwavelength instability around an accreting neutron star. Moreover, we show that the variability across the electromagnetic spectrum—from radio to X-ray—of both black holes and neutron stars at high accretion rates can be explained consistently if the accretion disks are unstable, producing relativistic ejections during transitions that deplete or refill the inner disk. Such a new association allows us to identify the main physical components responsible for the fast multiwavelength variability of highly accreting compact objects.
Chemotherapy (CT) is central to the treatment of triple negative breast cancer (TNBC), but drug toxicity and resistance place strong restrictions on treatment regimes. Fasting sensitizes cancer cells to a range of chemotherapeutic agents and also ameliorates CT-associated adverse effects. However, the molecular mechanism(s) by which fasting, or short-term starvation (STS), improves the efficacy of CT is poorly characterized.
The simultaneous determination of two inflammatory diseases biomarkers, namely procalcitonin (PCT) and interleukin-6 (IL-6), in human serum samples employing a Point-of-Care device based on Multi Area Reflectance Spectroscopy is presented. Dual-analyte detection was achieved using silicon chips with two silicon dioxide areas of different thickness, one functionalized with an antibody specific for PCT and the other with an antibody specific for IL-6. The assay included reaction of immobilized capture antibodies with mixtures of PCT and IL-6 calibrators with the biotinylated detection antibodies, streptavidin and biotinylated-BSA. The reader provided for the automated execution of the assay procedure, as well as for the collection and processing of the reflected light spectrum, the shift of which is correlated to analytes concentration in the sample. The assay was completed in 35 min and the detection limits for PCT and IL-6 were 2.0 and 0.01 ng/mL respectively. The dual-analyte assay was characterized by high reproducibility (the intra- and inter-assay coefficients of variation were less than 10% for both analytes) and accuracy (the percent recovery values ranged from 80 to 113% for both analytes). Moreover, the values determined for the two analytes in human serum samples with the assay developed were in good agreement with the values determined for the same samples by clinical laboratory methods. These results support the potential of the proposed biosensing device application for inflammatory biomarkers determination at the Point-of-Need
Harnessing the potential beneficial effects of kinase signalling through the generation of direct kinase activators remains an underexplored area of drug development(1-5). This also applies to the PI3K signalling pathway, which has been extensively targeted by inhibitors for conditions with PI3K overactivation, such as cancer and immune dysregulation. Here we report the discovery of UCL-TRO-1938 (referred to as 1938 hereon), a small-molecule activator of the PI3Kalpha isoform, a crucial effector of growth factor signalling. 1938 allosterically activates PI3Kalpha through a distinct mechanism by enhancing multiple steps of the PI3Kalpha catalytic cycle and causes both local and global conformational changes in the PI3Kalpha structure. This compound is selective for PI3Kalpha over other PI3K isoforms and multiple protein and lipid kinases. It transiently activates PI3K signalling in all rodent and human cells tested, resulting in cellular responses such as proliferation and neurite outgrowth. In rodent models, acute treatment with 1938 provides cardioprotection from ischaemia-reperfusion injury and, after local administration, enhances nerve regeneration following nerve crush. This study identifies a chemical tool to directly probe the PI3Kalpha signalling pathway and a new approach to modulate PI3K activity, widening the therapeutic potential of targeting these enzymes through short-term activation for tissue protection and regeneration. Our findings illustrate the potential of activating kinases for therapeutic benefit, a currently largely untapped area of drug development.
Many issues arise from the recession of sea cliffs, including threats to coastal communities and infrastructure. The best proxy to study cliff instability processes is the cliff face evolution. Unfortunately, due to its verticality, this proxy is difficult to observe and measure. This study proposed and compared three remote sensing methods based on structure-from-motion (SfM) photogrammetry or stereorestitution: boat-based SfM photogrammetry with smartphones, unmanned aerial system (UAS) or unmanned aerial vehicle (UAV) photogrammetry with centimetric positioning and Pléiades tri-stereo imagery. An inter-comparison showed that the mean distance between the point clouds produced by the different methods was about 2 m. The satellite approach had the advantage of covering greater distances. The SfM photogrammetry approach from a boat allowed for a better reconstruction of the cliff foot (especially in the case of overhangs). However, over long distances, significant geometric distortions affected the method. The UAS with centimetric positioning offered a good compromise, but flight autonomy limited the extent of the monitored area. SfM photogrammetry from a boat can be used as an initial estimate for risk management services following a localized emergency. For long-term monitoring of the coastline and its evolution, satellite photogrammetry is recommended.
This study aimed to investigate the ways subtypes of social withdrawal and dimensions of solitude are related to existential concerns in emerging adulthood. The links between social withdrawal/solitude and existential well-being are a highly neglected research issue. Participants were 774 emerging adults (50.4% males) aged 18?25 (M = 20.07) from Greece. They completed measures on social withdrawal, solitude, authenticity, meaning in life, existential anxiety, and existential loneliness. We used structural equation modeling to analyze the data. Results indicated that shyness, avoidance, and isolation were associated with more existential concerns, whereas unsociability was associated with less existential concerns. The solitude dimensions - enlightenment, freedom, intimacy, and loneliness - were differentially associated with existential concerns, with enlightenment exhibiting the most existential benefits. Findings showed that existential well-being is dependent on emerging adults? quality of withdrawal experiences and ability to make constructive use of solitude.
The goal of the paper is the design of soft sensors for single input single output (SISO) nonlinear processes. This goal is of essential importance for process monitoring, fault detection and fault isolation. The observer‐based technique, being a fruitful direction in soft sensor design, is followed to develop soft sensors for nonlinear processes with known dynamics and unknown physical parameters. A new and general approach, based on the identified I/O linear approximant system descriptions, around prespecified operating points, and a bank of switching linear observers, will be developed. The system property of the I/O reconstructability of the state space linear approximant of a nonlinear model is presented. The design of each observer is based on the I/O measurements and structural characteristics of the nonlinear process. Observer‐oriented target areas are introduced, and the respective dense web principle is formulated. The design is completed by the design of a data‐driven rule‐based system, providing stepwise switching among the observers of the bank. The number of observers of the bank is equal to the number of the linear approximants of the nonlinear process model and is equal to the number of the respective target operating areas. The target operating areas are required to satisfy the dense web principle. The information provided by the soft sensor is the estimation of the non‐measured variables of the process. The information used by the soft sensor is the identified I/O approximants of the process as well as the real time values of the measurement variables. The efficiency of the design scheme is illustrated through symbolic and numerical simulation results for a chemostat. The nonlinear model of the chemostat is initially approximated by a set of ten linear approximants. After, the I/O approximants are identified, the respective observers are designed and the target operating areas are determined, where several cases of the satisfaction of the dense web principle are investigated. The soft sensor is composed in terms of the designed observers. Simulation results illustrate the satisfactory performance of the designed soft sensor.
Extraordinary optical transmission (EOT) is a hallmark of surface plasmons and a precursor to nanoplasmonics and metamaterials. However, to the best of our knowledge, this effect has never been topologically protected in three dimensions, leaving it vulnerable to structural imperfections, nonlocal effects, and backreflections. We report broadband, three-dimensional unidirectional structures that allow for EOT (normalized transmission > 1) through deep-subdiffractional single holes, immune to these deleterious effects. These structures avoid unnecessary propagation losses and achieve maximum transmission through a single hole, limited only by unavoidable dissipative losses. In the limit of vanishing losses, the transmission through a deep-subdiffractional hole can approach unity, significantly surpassing existing devices, and rivaling the performance of negative-index ‘perfect’ lenses. The topological stability of these structures renders them robust against surface roughness, defects, and nonlocality, without the need for elaborate meta-structures or tapering.
Standard electronic computing based on nanoelectronics and logic gates has upended our lives in a profound way. However, suffering from, both, Moore’s law and Joule’s law, further development of logic devices based solely on elec-tricity has gradually stuck in the mire. All-optical logic devices are believed to be a potential solution for such a problem. This work proposes an all-optical digital logical system (AODLS) based on unidirectional (one-way propagation) modes in the microwave regime. In a Y-shaped module of the AODLS, the basic seven logic gates, including OR, AND, NOT, NOR, NAND, XOR, and XNOR gates, are achieved for continuous broadband operation relying on the existence of unidi-rectional electromagnetic signals. Extremely large extinction and contrast ratios are found in these logic gates. The idea of “negative logic” is used in designing the AODLS. Moreover, the authors further demonstrate that the AODLS can be assembled to multi-input and/or multi-output logical functionalities, which is promising for parallel computation. Besides, numerical simulations perfectly fit with and corroborate the theoretical analyses presented here. The low-loss, broadband, and robust characteristics of this system are outlined and studied in some detail. The AODLS consisting of unidirectional structures may open a new route for all-optical calculation and integrated optical circuits.
All-optical logic gates have been studied intensively owing to their potential to enable broadband, low-loss and high-speed communications. However, poor tunability has remained a key challenge in this field. In this work, we propose a Y-shaped structure composed of Yttrium Iron Garnet (YIG) layers that can serve as tunable all-optical logic gates, including, but not limited to, OR, AND and NOT gates, by applying external magnetic fields to magnetize the YIG layers. Our findings reveal that these logic gates are founded on protected one-way edge modes, where by tuning the wavenumber k of the operating mode to a sufficiently small (or even zero) value, the gates can become nearly immune to nonlocal effects. This not only enhances their reliability but also allows for maintaining extremely high precision in their operations. Furthermore, the operating band itself of the logic gates is also shown to be tunable. We introduce a straightforward and practical method for controlling and switching these gates between "work", "skip", and "stop" modes. These findings have potentially significant implications for the design of high-performance and robust all-optical microwave communication systems.