Unraveling the transcriptomic landscape of eye migration and visual adaptations during flatfish metamorphosis.

Flatfish undergo a remarkable metamorphosis from symmetrical pelagic larvae to fully asymmetrical benthic juveniles. The most distinctive features of this transformation is the migration of one eye. The molecular role of thyroid hormone in the metamorphosis process in flatfishes is well established. However, the regulatory network that facilitates eye movement remains enigmatic. This paper presents a morphological investigation of the metamorphic process in turbot eyes, using advanced imaging techniques and a global view of gene expression. The study covers migrant and non-migrant eyes and aims to identify the genes that are active during ocular migration. Our transcriptomic analysis shows a significant up-regulation of immune-related genes. The analysis of eye-specific genes reveals distinct patterns during the metamorphic process. Myosin is highlighted in the non-migrant eye, while ependymin is highlighted in the migrant eye, possibly involved in optic nerve regeneration. Furthermore, a potential association between the alx3 gene and cranial restructuring has been identified. Additionally, it confirmed simultaneous adaptation to low light in both eyes, as described by changes in opsins expression during the metamorphic process. The study also revealed that ocular migration activates systems asynchronously in both eyes, providing insight into multifaceted reorganization processes during metamorphosis of flatfish.

Interlayer Coupling Controlled Ordering and Phases in Polar Vortex Superlattices.

The recent discovery of polar topological structures has opened the door for exciting physics and emergent properties. There is, however, little methodology to engineer stability and ordering in these systems, properties of interest for engineering emergent functionalities. Notably, when the surface area is extended to arbitrary thicknesses, the topological polar texture becomes unstable. Here we show that this instability of the phase is due to electrical coupling between successive layers. We demonstrate that this electrical coupling is indicative of an effective screening length in the dielectric, similar to the conductor-ferroelectric interface. Controlling the electrostatics of the superlattice interfaces, the system can be tuned between a pure topological vortex state and a mixed classical-topological phase. This coupling also enables engineering coherency among the vortices, not only tuning the bulk phase diagram but also enabling the emergence of a 3D lattice of polar textures.

Clinical Presentation Differences Among Four Subtypes of Femoroacetabular Impingement: A Case-Control Study.

OBJECTIVE: The aims of this study were to assess the psychological, functional, and physical differences between patients with femoroacetabular impingement (FAI) syndrome and individuals who were asymptomatic (controls) to analyze clinical differences among 4 subtypes of FAI (cam type, cam type with labral tear, pincer type, and pincer type with labral tear), to calculate the correlations among the variables described, and to identify risk factors contributing to the hip function variance. METHODS: A case-control study was conducted at a hospital rehabilitation unit with a cohort of individuals who were asymptomatic (controls) and a cohort of patients with FAI. Sociodemographic characteristics, pain intensity, psychological health status, hip range of motion (RoM), hip isometric strength, and hip function were assessed. RESULTS: A total of 69 controls and 69 patients with FAI were analyzed. Although sociodemographic characteristics were comparable between samples, poorer hip RoM, strength, and psychological health were found for the cases. FAI subtypes showed no significant pain intensity, psychological health, or RoM differences (except for hip adduction), but hip strength differed among FAI subtypes. Multiple significant correlations between psychological health, pain intensity, RoM, strength, and hip function were found. The variance values of the International Hip Outcome Tool, Hip Outcome Score (HOS) for daily living activities, and HOS for sports activities were partially explained (47.6%, 36.0%, and 21.6%, respectively) on the basis of kinesiophobia, hip strength, self-efficacy, and anxiety. CONCLUSION: Patients with FAI showed poorer psychological health, hip RoM, and strength than individuals who were asymptomatic and had similar sociodemographic characteristics. FAI subtype influenced the patients' clinical presentations. Hip strength, kinesiophobia, anxiety, and self-efficacy should be targeted for improving hip function, as they have been demonstrated to be important contributors to hip disability. IMPACT: This study demonstrated that pain catastrophizing, hip strength, and hip adduction differed among FAI subtypes. However, hip function and pain intensity were comparable between FAI subtypes.

The Relationship between Vegetarian Diet and Sports Performance: A Systematic Review.

INTRODUCTION: In recent years, the vegetarian diet has increased in popularity among athletes. The aim of this review is to ascertain the differences in variables related to performance, nutritional intake, and health in athletes according to whether they are omnivores or vegetarians. METHODOLOGY: A literature search was carried out in different databases: PubMed, Web of Science, Dialnet, and Cochrane. The keywords used were "vegetarian diet", "vegan diet", "exercise", "sport", and "performance". After applying different inclusion criteria, six studies were included in the review. RESULTS: No significant differences were obtained in variables related to physical performance (adherence exercise, Vo2Máx, muscle power, and sprint test) or health (body composition, psychological well-being, and social relationships), but dietary intake was significantly higher in carbohydrates and lower in proteins in vegetarian athletes (p < 0.05). CONCLUSIONS: It cannot be affirmed that vegetarian subjects have a higher sports performance, for which more research should be carried out.

Electromyographic Activity of the Pelvic Floor Muscles and Internal Oblique Muscles in Women during Running with Traditional and Minimalist Shoes: A Cross-Over Clinical Trial.

The study aimed to investigate the effects of footwear on the electromyographic (EMG) activity of pelvic floor muscles (PFMs) and internal oblique (IO) muscles during running at different speeds. The study also aimed to explore the correlation between EMG activity of PFMs and IO muscles and participants' morphological characteristics. Ten nulliparous female runners were included in the study. The participants ran for 90 s at speeds of 9, 11, and 13 km/h wearing both traditional and minimalist shoes. EMG outcomes were presented as a percentage of maximum voluntary contraction (%MVC). Comparative analysis was conducted using the Wilcoxon rank test. Correlational analysis was performed using the Rho-Spearman correlation coefficient. The %MVC for the IO muscles was significantly lower when using minimalist shoes compared to traditional shoes (p = 0.04). No statistically significant differences were found for the PFMs (p > 0.05). The study also observed large correlations between age and %MVC of the PFMs and IO muscles (rho = -0.64; p = 0.04). Minimalist shoes decreased the activity of IO muscles in female runners. However, no significant differences in EMG activity of PFMs were found when comparing traditional and minimalist footwear. The long-term effects of minimalist footwear on EMG activity of PFMs and IO muscles, as well as their relationship to morphological characteristics, require further investigation.

The emergence of three-dimensional chiral domain walls in polar vortices.

Chirality or handedness of a material can be used as an order parameter to uncover the emergent electronic properties for quantum information science. Conventionally, chirality is found in naturally occurring biomolecules and magnetic materials. Chirality can be engineered in a topological polar vortex ferroelectric/dielectric system via atomic-scale symmetry-breaking operations. We use four-dimensional scanning transmission electron microscopy (4D-STEM) to map out the topology-driven three-dimensional domain walls, where the handedness of two neighbor topological domains change or remain the same. The nature of the domain walls is governed by the interplay of the local perpendicular (lateral) and parallel (axial) polarization with respect to the tubular vortex structures. Unique symmetry-breaking operations and the finite nature of domain walls result in a triple point formation at the junction of chiral and achiral domain walls. The unconventional nature of the domain walls with triple point pairs may result in unique electrostatic and magnetic properties potentially useful for quantum sensing applications.

Pure Chiral Polar Vortex Phase in PbTiO3/SrTiO3 Superlattices with Tunable Circular Dichroism.

Nontrivial polarization textures have been demonstrated in ferroelectric/dielectric superlattices, where the electrostatic, elastic, and different gradient energies compete in a delicate balance. When PbTiO3/SrTiO3 superlattices are grown on DyScO3, the coexistence of ferroelectric domains and vortex structure is observed for n = 12-20 unit cells. Here, we report an approach to achieve single-phase vortex structures in superlattices by controlling the epitaxial strain using Sr1.04Al0.12Ga0.35Ta0.50O3 substrates. The domain width follows Kittel's law with the thickness of the ferroelectric PbTiO3 layers. A phase transition from vortex to a disordered phase with temperature is characterized by the correlation length. Resonant soft X-ray diffraction circular dichroism at the titanium L-edge reveals enhanced chirality with the thickness of the ferroelectric layer. These results are supported by second-principles simulations, which demonstrate that the integrated helicity increases with n. The stabilization of chiral single-phase polar vortices in ferroelectric/dielectric superlattices can enable novel optoelectronic devices with enhanced ferroelectric-light interaction.

Physical Activity Levels, Eating Habits, and Well-Being Measures in Students of Healthcare Degrees in the Second Year of the COVID-19 Pandemic.

BACKGROUND: When the first cases of COVID-19 (caused by SARS-CoV-2 virus infection) were discovered, exceptional norms to fight the spread of the virus were established by applying movement restrictions (lockdown) in many countries. These unprecedented norms led to sedentary behaviours and less healthy diets which could persist for much longer after lockdown. The aim of this study was to analyse the physical activity, eating habits, self-perceived well-being, and toxic habits, as well as the perceived changes of these habits with respect to the pre-pandemic period, in a population of university students in the second year of the COVID-19 pandemic. METHODS: A single-centre, cross-sectional study was conducted in a population of university students of healthcare degrees. A total of 961 students (639 (66.5%) women and 322 (33.5%) men) signed the informed consent and completed the questionnaire. The study was conducted through an anonymous survey, which was voluntarily self-completed by the students on an online platform. The questionnaire was based on the Spanish Health Survey and it was divided into six main parts: demographic and anthropometric characteristics, physical activity, eating habits, well-being measures (sleeping habits, health state, and stress), toxic habits, and perception of the influence of the COVID-19 pandemic on the variables described. RESULTS AND CONCLUSIONS: The results showed that, during the second year of the pandemic, statistically significant dependence was identified for those students that showed higher levels of physical activity with greater perceived physical activity (p < 0.05), healthier eating habits (p < 0.05), and a better self-perceived health state (p < 0.05), with respect to the 12 months before the COVID-19 pandemic. On the other hand, there was a negative correlation between the sedentary students and greater perceived physical activity (p < 0.05). With regard to toxic habits and physical activity, a significant correlation was only detected between sedentary behaviour and cocaine consumption (p < 0.05). Analysing eating habits, it was observed that the students who smoked, consumed alcohol, and binge drank had low adherence to the Mediterranean diet (p < 0.05). In addition, those students with high stress levels slept less than 7 h (p < 0.05).

Genome-wide chromatin accessibility and gene expression profiling during flatfish metamorphosis.

Metamorphosis is a widely studied post-embryonic process in which many tissues undergo dramatic modifications to adapt to the new adult lifestyle. Flatfishes represent a good example of metamorphosis in teleost fishes. During metamorphosis of flatfish, organ regression and neoformation occur, with one of the most notable changes being the migration of one of the eyes to the other side of the body. In order to create a useful and reliable tool to advance the molecular study of metamorphosis in flatfish, we generated a chromatin accessible atlas as well as gene expression profile during four developmental stages ranging from a phylotypic to a post-metamorphic stage. We identified 29,019 differentially accessible chromatin regions and 3,253 differentially expressed genes. We found stage-specific regulatory regions and gene expression profiles, supporting the quality of the results. Our work provides strongly reproducible data for further studies to elucidate the regulatory elements that ensure successful metamorphosis in flatfish species.

Emergent chirality in a polar meron to skyrmion phase transition.

Polar skyrmions are predicted to emerge from the interplay of elastic, electrostatic and gradient energies, in contrast to the key role of the anti-symmetric Dzyalozhinskii-Moriya interaction in magnetic skyrmions. Here, we explore the reversible transition from a skyrmion state (topological charge of -1) to a two-dimensional, tetratic lattice of merons (with topological charge of -1/2) upon varying the temperature and elastic boundary conditions in [(PbTiO3)16/(SrTiO3)16]8 membranes. This topological phase transition is accompanied by a change in chirality, from zero-net chirality (in meronic phase) to net-handedness (in skyrmionic phase). We show how scanning electron diffraction provides a robust measure of the local polarization simultaneously with the strain state at sub-nm resolution, while also directly mapping the chirality of each skyrmion. Using this, we demonstrate strain as a crucial order parameter to drive isotropic-to-anisotropic structural transitions of chiral polar skyrmions to non-chiral merons, validated with X-ray reciprocal space mapping and phase-field simulations.

Effects of Creatine Supplementation after 20 Minutes of Recovery in a Bench Press Exercise Protocol in Moderately Physically Trained Men.

BACKGROUND: The aims of this study were to analyse the effect of creatine supplementation on the performance improvement in a bench pressing (BP) strength test of muscle failure and to evaluate muscle fatigue and metabolic stress 20 min after the exercise. METHODS: Fifty young and healthy individuals were randomly assigned to a creatine group (n = 25) or a placebo group (n = 25). Three exercise sessions were carried out, with one week of rest between them. In the first week, a progressive load BP test was performed until the individuals reached the one repetition maximum (1RM) in order to for us obtain the load-to-velocity ratio of each participant. In the second week, the participants conducted a three-set BP exercise protocol against 70% 1RM, where they performed the maximum number of repetitions (MNR) until muscle failure occurred, with two minutes of rest between the sets. After one week, and following a supplementation period of 7 days, where half of the participants consumed 0.3 g·kg-1·day-1 of creatine monohydrate (CR) and the other half consumed 0.3 g·kg-1·day-1 of placebo (PLA, maltodextrin), the protocol from the second week was repeated. After each set, and up to 20 min after finishing the exercise, the blood lactate concentrations and mean propulsive velocity (MPV) at 1 m·s-1 were measured. RESULTS: The CR group performed a significantly higher number of repetitions in Set 1 (CR = 14.8 repetitions, PLA = 13.6 repetitions, p = 0.006) and Set 2 (CR = 8 repetitions, PLA = 6.7 repetitions, p = 0.006) after supplementation, whereas no significant differences were seen in Set 3 (CR = 5.3 repetitions, PLA = 4.7 repetitions, p = 0.176). However, there was a significant increase in blood lactate at minute 10 (p = 0.003), minute 15 (p = 0.020), and minute 20 (p = 0.015) after the exercise in the post-supplementation period. Similarly, a significant increase was observed in the MPV at 1 m·s-1 in the CR group with respect to the PLA group at 10, 15, and 20 min after the exercise. CONCLUSIONS: Although the creatine supplementation improved the performance in the strength test of muscle failure, the metabolic stress and muscle fatigue values were greater during the 20 min of recovery.

The Chester Step Test Is a Reproducible Tool to Assess Exercise Capacity and Exertional Desaturation in Post-COVID-19 Patients.

Many people recovering from an acute episode of coronavirus disease (COVID-19) experience prolonged symptoms. Exercise testing is a feasible and cost-effective option for assessing exercise tolerance, fatigue, and dyspnea related to effort. Being that the Chester step test (CST) is a progressive, submaximal test for predicting aerobic capacity, it could be a good option to explore. This study aimed to determine the reproducibility of CST for assessing exertional desaturation and exercise capacity in patients post-COVID-19 disease. A cross-sectional study was conducted on post-COVID-19 patients. Two attempts of the CST were performed. The intraclass correlation coefficient (ICC) was used to assess agreement between the two tests. Forty-two symptomatic post-COVID-19 patients were included, the mean age was 53.8 ± 10.3 years, and 52% were female. There was no significant difference between both tests (p = 0.896). Twenty-four percent of participants (10 cases) had a clinically significant decrease in SpO2 at the first assessment, compared to 30.1% (13 cases) at the second, with no significant difference. An ICC of 0.993 (95% CI: 0.987 to 0.996) was obtained for the total number of steps in the CST.

Structural Chirality of Polar Skyrmions Probed by Resonant Elastic X-Ray Scattering.

An escalating challenge in condensed-matter research is the characterization of emergent order-parameter nanostructures such as ferroelectric and ferromagnetic skyrmions. Their small length scales coupled with complex, three-dimensional polarization or spin structures makes them demanding to trace out fully. Resonant elastic x-ray scattering (REXS) has emerged as a technique to study chirality in spin textures such as skyrmions and domain walls. It has, however, been used to a considerably lesser extent to study analogous features in ferroelectrics. Here, we present a framework for modeling REXS from an arbitrary arrangement of charge quadrupole moments, which can be applied to nanostructures in materials such as ferroelectrics. With this, we demonstrate how extended reciprocal space scans using REXS with circularly polarized x rays can probe the three-dimensional structure and chirality of polar skyrmions. Measurements, bolstered by quantitative scattering calculations, show that polar skyrmions of mixed chirality coexist, and that REXS allows valuation of relative fractions of right- and left-handed skyrmions. Our quantitative analysis of the structure and chirality of polar skyrmions highlights the capability of REXS for establishing complex topological structures toward future application exploits.

Effects of minimalist shoes on pelvic floor activity in nulliparous women during running at different velocities: a randomized cross-over clinical trial.

In the last decade, minimalist shoes have gained popularity as an alternative to traditional shoes. The aim of the present study was to determine the short-term effects of minimalist shoes in femur range of motion (ROM) and cadence. The secondary objectives were the assessment of the electromyographic activity of the pelvic floor muscles (PFM) in nulliparous women. A randomized, prospective cross-over clinical trial design was used for the study. A total of 51 participants were randomly allocated into a two-sequence crossover design (AB/BA crossover design). Femur ROM, cadence and PFM activity were recorded. The femur ROM at 6 km/h was greater with the minimalist shoes by 1.62 degrees than with the traditional ones (p = 0.001). There was a main effect of the type of shoe (p = 0.015) systematically observing a higher running cadence with the minimalist shoe compared to the traditional one. Electromyographic activity of the PFM revealed significant differences for 11 km/h for the total average (p = 0.027) and the minimum peaks at 9 km/h (p = 0.011) and 11 km/h (p = 0.048) for the minimalist shoe with respect to the traditional shoes. Minimalist shoes produce immediate effects on the biomechanical variables of running. An increase was observed in the femur ROM at 6 km/h and in the cadence at 11 km/h with the use of minimalist shoes. The use of minimalist shoes increased the electromyographic activation of the PFM in the minimum peaks at speeds of 9 and 11 km/h and in the total average at speeds of 11 km/h compared to the traditional shoe.

Validity and Test-Retest Reliability of the Spanish Version of the International Hip Outcome Tool (iHOT-12Sv).

Objective: To develop a Spanish version of the international Hip Outcome Tool questionnaire (iHOT-12Sv) for assessing the psychometric characteristics (internal consistency, convergent validity, test−retest reliability, and floor and ceiling effects) of this version in physically active patients with hip pain. Methods: After conducting the translation and transcultural adaptation, a consecutive sample of patients with labral tear injury and/or femoroacetabular impingement (Pincer or Cam type) were recruited in a Spanish Hospital. Patients completed the iHOT-12Sv and the Spanish version of the iHOT-33 and the Hip Outcome Score (HOS). Internal consistency was calculated using Cronbach's alpha; convergent validity was evaluated using Spearman correlation coefficients (Rho) with iHOT-33 and HOS; test−retest reliability was examined using the intraclass correlation coefficient (ICC), standard error of measurement (SEM), and minimal detectable changes (MDC); and floor and ceiling effects were calculated as the percentage of patients who obtained the minimum and maximum score. Results: One hundred and fifty-three patients (64.7% males) participated in this study. Cronbach's alpha of 0.92 revealed the excellent internal consistency. In addition, the iHOT-12Sv demonstrated strong to very strong correlations with the HOS (Rho ranged from 0.741 to 0.827; p < 0.001) and the iHOT-33 (Rho = 0.932; p < 0.001), respectively; acceptable test-retest reliability (ICC = 0.86 to 0.94); SEM = 6.21 and MDC = 17.22; and no floor or ceiling effects were found. Conclusions: The iHOT-12Sv can be used as a valid and reliable tool for clinical evaluation of physically active patients with hip pathology. However, the full version is preferable for research purposes aiming to assess changes in hip function.

Similar Slow Component of Oxygen Uptake and Ventilatory Efficiency between an Aerobic Dance Session on an Air Dissipation Platform and a Constant-Load Treadmill Test in Healthy Women.

There is a lack of evidence about the slow component of oxygen consumption (V.O2sc) and ventilatory efficiency (slope VE·VCO2−1) during an aerobic dance (AD) session on an air dissipation platform (ADP) despite the key role played in endurance exercises. This research was designed to assess V.O2sc, ventilatory efficiency, and blood lactate concentration by comparing two exercise modes: AD session on an ADP versus treadmill test at a constant-load intensity of the first ventilatory threshold (VT1). In the first session, an incremental treadmill test was completed. In sessions 2 and 3, the participants were randomly assigned to the AD session on an ADP or to a treadmill constant-load test at VT1 intensity to determine their cardioventilatory responses. In addition, their blood lactate levels and ratings of perceived exertion (RPE, CR-10) were evaluated. No significant differences were found between the constant-load treadmill test and AD session on an ADP with respect to V.O2sc, VE VCO2−1 slope, and RPE (p > 0.05). Higher blood lactate concentrations were observed in an AD session on an ADP than in a constant-load treadmill test at 10 min (p = 0.003) and 20 min (p < 0.001). The two different exercise modalities showed similar V.O2sc and VE·VCO2−1 slope, even though the blood lactate concentrations were different.

Effects of Capacitive-Resistive Electric Transfer on Sports Performance in Paralympic Swimmers: A Stopped Randomized Clinical Trial.

Throughout history a variety of therapeutic tools have been studied as possible enhancers of sports activities. This study proposes the use of Capacitive-Resistive Electric Transfer (CRET) as a performance booster to paralympic athletes, specifically those belonging to the Spanish Paralympic swimming committee. The study was a randomized, single-blind, and observer-blind, crossover clinical trial. Six athletes were randomly assigned to three groups: one treated with CRET (A); a placebo group (B) and a control group (C). The CRET group attended a twenty-minute session before being subjected to pool trials at distances of 50 and 100 m at maximum performance. Measurements were in two dimensions: time in seconds and the Borg scale for perceived exertion. Comparisons between groups were made with respect to distance and the main variables. In the case of perceived exertion, no significant changes were observed in any of the distances; however, in the case of the time variable, a significant difference was observed between Group A vs. Personal Record at 100 m distance (76.3 ± 6.8 vs. 68.4 ± 3.3). The proposed protocol and level of hyperthermia applied suggest refusal of CRET use for the 100-m distance a few minutes before sports practice. Our analysis suggests the need to modify the presented protocol. ClinicalTrials.gov identifier under NCT number: NCT04336007.

Neuromuscular Fatigue and Metabolic Stress during the 15 Minutes of Rest after Carrying Out a Bench Press Exercise Protocol.

Background: Velocity loss (VL) at 1 m·s−1 can help to determine neuromuscular fatigue after performing an exercise protocol. The aim of this study was to analyse muscle fatigue and metabolic stress during the 15 min that follow the execution of a bench press (BP) exercise protocol. Methods: Forty-four healthy male students of sports science performed two exercise sessions separated by one week of rest. In the first week, the participants carried out a test with progressive loads in the (BP) exercise until reaching the one-repetition maximum (1RM) in order to obtain the load−velocity relationship of each participant. In the second week, each participant conducted three BP exercise sets at an intensity of 70% of 1RM, determining this load through the mean propulsive velocity (MPV) obtained from the individual load−velocity relationship, with the participants performing the maximum number of repetitions (MNR) to muscle failure. Two minutes of rest were allocated between sets. MPV at 1 m·s−1 and blood lactate concentrations were recorded before executing the exercise and at minute 0, 5, 10 and 15 after performing the exercise protocol. Results: A two-factor repeated measures ANOVA was performed. MPV at 1 m·s−1 in minute 0 post-exercise was −33.3% (p < 0.05), whereas in minute 10 and 15 post-exercise, it was ≈−9% (p > 0.05). Regarding the blood lactate levels, significant differences were observed in all measurements before and after the exercise protocol (p < 0.001), obtaining ≈7 mmol·L−1 at minute 10 post-exercise and 4.3 mmol·L−1 after 15 min of recovery. Conclusions: MPV with medium or moderate loads shows a certain recovery from minute 10 of rest. However, the blood lactate levels are still high (>5 mmol·L−1). Therefore, although there seem to be certain conditions to reach a similar maximum MPV peak, the residual fatigue at the neuromuscular level and the non-recovery of metabolic homeostasis would hinder the reproduction of these protocols, both at the level of applied stimulus and from a methodological perspective, since a long recovery time would be required between sets and exercises.

Toxic Habits and Well-Being Measures in Spanish Healthcare University Students during the COVID-19 Pandemic.

BACKGROUND: Unhealthy lifestyles are strongly entrenched in healthcare universities and have sometimes been linked to stress or lack of sleep. This study investigated the prevalence of toxic habits (smoking, patterns of harmful alcohol use, and illicit drug use), stress levels, perceived health status, and sleep duration and assessed the connections between toxic habits and said well-being measures, as well as healthcare students' perception of the influence of the COVID-19 pandemic on these health-related behaviors. METHODS: In a cross-sectional study, healthcare students from Alfonso X University (Spain) completed a health survey composed of Alcohol Use Disorders Identification Test (AUDIT-C), Perceived Stress Scale (PSS-10), self-perceived health status, and the number of hours of sleep. RESULTS: A total of 997 healthcare students completed the survey, of which 982 were analyzed. Being a smoker (32.2%) was associated with worse health status and insufficient sleep. Risk drinkers (33.2%) were associated with being female, and the consumption of cannabinoids (6.7%), with being male. These three toxic habits were related to each other. High levels of stress (28.2%) were correlated with worse ratings in the perception of health status (29.2%) and with insufficient sleep (45.8%), and all of them were associated with the female sex. Respectively, 49.3% and 44.2% of students recognized a worsening in their perception of stress and their sleep habits during the pandemic. CONCLUSION: Healthcare universities must carry out health promotion programs for stress management, sleep habits, and unhealthy lifestyles.

Layered gallium sulfide optical properties from monolayer to CVD crystalline thin films.

Interest in layered van der Waals semiconductor gallium monosulfide (GaS) is growing rapidly because of its wide band gap value between those of two-dimensional transition metal dichalcogenides and of insulating layered materials such as hexagonal boron nitride. For the design of envisaged optoelectronic, photocatalytic and photonic applications of GaS, the knowledge of its dielectric function is fundamental. Here we present a combined theoretical and experimental investigation of the dielectric function of crystalline 2H-GaS from monolayer to bulk. Spectroscopic imaging ellipsometry with micron resolution measurements are corroborated by first principle calculations of the electronic structure and dielectric function. We further demonstrate and validate the applicability of the established dielectric function to the analysis of the optical response of c-axis oriented GaS layers grown by chemical vapor deposition (CVD). These optical results can guide the design of novel, to our knowledge, optoelectronic and photonic devices based on low-dimensional GaS.