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Soldiers, athletes, and rescue personnel must often maintain cognitive focus while performing intense, prolonged, and physically demanding activities. The simultaneous activation of cognitive and physical functions can disrupt their performance reciprocally. In the current study, we developed and demonstrated the feasibility of a virtual reality (VR)-based experimental protocol that enables rigorous exploration of the effects of prolonged physical and cognitive efforts. A battery of established neurocognitive tests was used to compare novel cognitive tasks to simulated loaded marches. We simulated a 10-km loaded march in our virtual reality environment, with or without integrated cognitive tasks (VR-COG). During three experimental visits, participants were evaluated pre- and post-activity, including the Color Trail Test (CTT), the Synthetic Work Environment (SYNWIN) battery for assessing multitasking, and physical tests (i.e., time to exhaustion). Results show that Strong or moderate correlations (r ≥ 0.58, p ≤ 0.05) were found between VR-COG scores and scores on the cognitive tests. Both the SYNWIN and CTT showed no condition effects but significant time effects, indicating better performance in the post-activity assessment than in the pre-activity assessment. This novel protocol can contribute to our understanding of physical-cognitive interactions, since virtual environments are ideal for studying high performance professional activity in realistic but controlled settings. [ABSTRACT FROM AUTHOR]

Food deprivation can occur for different reasons. Fasting (<24 h duration) occurs to meet religious or well-being goals. Starvation (>1-day duration) occurs when there is intentional (hunger strike or treatment of a medical condition) or unintentional (anorexia nervosa, drought, epidemic famine, war, or natural disaster) food deprivation. A scoping review was undertaken using the PubMed database to explore 1805 abstracts and review 88 eligible full-text articles to explore the adaptive relationships that emerge between cortisol, insulin, glucagon, and thyroid hormones on the metabolic pathways of macronutrients in humans during fasting and starvation. The collected data indicate that fasting and starvation prime the human body to increase cortisol levels and decrease the insulin/glucagon ratio and triiodothyronine (T3) levels. During fasting, increased levels of cortisol and a decreased insulin/glucagon ratio enhance glycogenolysis and reduce the peripheral uptake of glucose and glycogenesis, whereas decreased T3 levels potentially reduce glycogenolysis. During starvation, increased levels of cortisol and a decreased insulin/glucagon ratio enhance lipolysis, proteolysis, fatty acid and amino acid oxidation, ketogenesis, and ureagenesis, and decreased T3 levels reduce thermogenesis. We present a potential crosstalk between T3 and the above hormones, including between T3 and leptin, to extend their adaptive roles in the metabolism of endogenous macronutrients during food deprivation. [ABSTRACT FROM AUTHOR]

In recent years, an increasing research interest has been seen in the clinical consequences of hamstring-muscle injuries in sports. Yet the literature is lacking on hamstring flexibility and it correlations with physical performance and injury risk-factors, especially among young basketball players. The aim of this study, therefore, was to examine the relationships between hamstring flexibility, physical performance, and injuries among young basketball players. The study, which was conducted during 2022- 2023, including 114 basketball players aged 12-17 years. Anthropometric data, hamstring flexibility test results, and physical performance data were collected. A positive correlation was seen between hamstring flexibility and physical performance. However, no correlation was found between hamstring flexibility and injury prevalence and/or visits to a physician. The findings of this study emphasize the importance of including flexibility exercises in basketball training programs, as a means for maximizing performance and possibly preventing injuries. [ABSTRACT FROM AUTHOR]

Simple Summary: In the present work, calcium was found to prevent degradation of factor VIII during intermittent motion. In addition, calcium supplementation in drinking water consumed by mice increased factor VIII in blood and striated muscle. The clinical relevance of this work is that oral calcium may be evaluated as a potential supportive therapy in hemophilia patients. Another aspect is that food additives with calcium may increase factor VIII level, which is known to contribute to both arterial and venous thrombosis. Background: Hemophilia A and B induce recurrent bleeding episodes, mainly in skeletal muscles and joints that are in intermittent motion. We have previously demonstrated that intermittent motion contributes to increased degradation of factors VIII and IX. Objectives: Given that calcium ions are known to enhance factor VIII–von Willebrand factor (vWF) interaction, the present study has investigated the role of these ions on factors VIII and IX in the condition of motion. Methods: The effects of calcium ions were assessed using purified proteins via Western blot, factor VIII activity, immunocytochemistry, and in Institute of Cancer Research (ICR) mice with no specific genetic background. Results: Calcium was found to prevent degradation of plasma-derived factor VIII but not that of factor IX, during intermittent motion. Calcium levels in the microcirculation of mouse striated muscles were elevated following movement, enabling prevention of factor VIII degradation in normal physiology. Calcium supplementation in drinking water increased factor VIII levels in blood and striated muscles of ICR mice during movement. Conclusions: calcium ions decrease factor VIII degradation in the condition of motion. Further research on the impact of calcium salt oral supplementation on hemophilia patients is warranted. [ABSTRACT FROM AUTHOR]

The article reports on the current status of the Baksan Large Neutrino Telescope project and describes some selective results of the first stage of the project, a detector prototype with a liquid scintillator mass of 0.5 tons. The results of the second stage of the project, a prototype with liquid scintillator mass of 5 tons, and project prospects also presented. [ABSTRACT FROM AUTHOR]

Metal-loaded liquid organic scintillators (MeLS) are discussed from the point of view of light yield at high metal loading (Gd, Nd, Zr, In). It is shown that, when metal -diketonates are introduced into the scintillator, its light yield is always lower than when carboxylates are used, which is explained by the structural difference between these complexes. The nature of the metal in some cases (Nd) also affects the light attenuation length and, consequently, the MeLS light yield. The composition of the solvent (the fraction of aromatics in the main solvent) and the degree of purification of the introduced metal complex also have a significant effect on the light yield. [ABSTRACT FROM AUTHOR]

Low background segmented liquid scintillator detector, doped with an indium as a target for solar neutrino registration, can be used for measuring total solar neutrino spectrum including neutrinos. A detector consisting of small modules filled with liquid scintillator in the volume of 1–2 L is considered. Silicon matrices are used for light collection. The background of indium beta-activity is suppressed by triple coincidences. The detector of such a type can measure Be neutrino flux with high accuracy and independently check the measurement performed by the Borexino Collaboration. [ABSTRACT FROM AUTHOR]

The energy resolution is calculated for a neodymium-containing liquid organic scintillation detector (Nd-OS) with a volume of several liters to search for neutrinoless double beta decay of 150Nd as a function of the neodymium concentration up to 5 g/L. The results are presented in detailed tables and graphs. [ABSTRACT FROM AUTHOR]

In the TeV energy domain, it becomes difficult and very costly to control the trajectories of particles using electromagnets to obtain the extracted beams on accelerators. Highly gradient devices based on curved crystals are more suitable for these purposes. These crystals can work as super-strong lenses with a focal length of less than 1 m and with an equivalent magnetic field of 1000 T. In this paper, a scheme for the formation of a divergent beam with an energy of 50 GeV by two sequentially arranged focusing crystals is implemented to create an axially symmetric beam with a small divergence of 30 µrad in both horizontal and vertical planes. One promising application of such a scheme is the creation of high-energy neutrino beams. [ABSTRACT FROM AUTHOR]

The most common clinical presentation of hemophilia A and hemophilia B is bleeding in large joints and striated muscles. It is unclear why bleeding has a predilection to affect joints and muscles. As muscles and joints are involved in intermittent movement, we explored whether this phenomenon could be associated with an impact on factor VIII and IX levels. Purified proteins and a mouse model were assessed using coagulation assays, Western blot analysis and immuno-staining. Movement caused an increase in thrombin activity and a decrease in factor VIII and factor IX activity. The decrease in factor VIII activity was more significant in the presence of thrombin and during movement. Under movement condition, sodium ions appeared to enhance the activity of thrombin that resulted in decreased factor VIII activity. Unlike factor VIII, the reduction in factor IX levels in the movement condition was thrombin-independent. High factor VIII levels were found to protect factor IX from degradation and vice versa. In mice that were in movement, factor VIII and IX levels decreased in the microcirculation of the muscle tissue compared with other tissues and to the muscle tissue at rest. Movement had no effect on von Willebrand factor levels. Movement induces reduction in factor VIII and IX levels. It enables an increase in the binding of sodium ions to thrombin leading to enhanced thrombin activity and augmented degradation of factor VIII. These data suggest a potential mechanism underlying the tendency of hemophilia patients to bleed in muscles and joints. [ABSTRACT FROM AUTHOR]

The current state of the Baksan Large Neutrino Telescope project is reviewed. Selected results are presented from the first stage of the project, a prototype detector with a liquid scintillator weighing 0.5 tons. Results from the second stage of the project, a prototype with a liquid scintillator having a mass of five tons, are described along with prospects for the project. [ABSTRACT FROM AUTHOR]

It becomes difficult and expensive to control TeV-particle trajectories using electromagnets to obtain extracted beams at accelerators. For these purposes, high-gradient devices based on bent crystals are more suitable. These crystals can serve as superstrong lenses with a focal length of less than 1 m with an equivalent magnetic field of 1000 T. In this work, a scheme based on two successive focusing crystals has been implemented to form a 50 GeV axially symmetric beam with a small divergence of 30 μrad in both the horizontal and vertical planes. One of the promising applications of this scheme is the creation of high-energy neutrino beams. [ABSTRACT FROM AUTHOR]

Synthine and T-6 propellant are studied as new basic solvents for creating liquid organic scintillators. The light attenuation length in these solvents (both those obtained from the manufacturer and those subjected to chromatographic purification on Al O ) was measured along with the relative light yield of scintillators based on them. The chemical composition of synthine was determined by the method of chromato-mass spectrometry and UV spectrophotometry. A Nd-loaded scintillator ( 9 g/L) based on a synthine–pseudocumene mixture was created, and its light yield (LY 60 ) was measured with respect to a scintillator based on linear alkyl benzene (LAB). [ABSTRACT FROM AUTHOR]

The compatibility of memristor materials with advanced complementary metal-oxide-semiconductor (CMOS) technology is a key factor for microelectronics element base manufacturing. Therefore, we continued studying previously fabricated CMOS-compatible Ni/Si3N4/SiO2/p+-Si samples. We approximated volt-ampere characteristics (VAC) at different temperatures using the general form of the spatial charge-limiting current (SCLC) equation assuming exponential and Gaussian trap distribution within the band gap of Si3N4. Our approximation demonstrated better experimental data matching compared to previous work, where the approximation was based on the uniform trap distribution law. Further, we performed another additional sample measurement set of the samples to evaluate the parameters of the low-resistance state (LRS) variations at different temperatures. Analysis of these measurements allowed us to estimate the temperatures at which the samples will retain LRS for 10 years. [ABSTRACT FROM AUTHOR]

The aim of this study consisted in an investigation of the variability and functional status of the Helicobacter pylorioipA gene by using a sequencing method and evaluation of the association of oipA functionality with the cagPAI genes and clinical outcomes. The object of the study was 84 samples of H. pylori DNA isolated from antrum biopsies of the gastric mucosa from patients with gastroduodenal diseases. The presence of the cagPAI genes were determined by PCR. The oipA gene status was determined using sequencing reactions. Our results revealed that 79.8% of H. pylori samples had the "on" status of the oipA gene, while the remaining 20.2% of the samples had a nonfunctional gene status. The "on" status of the oipA gene was found to be statistically associated with an increased risk of developing duodenal ulcer compared with superficial gastritis (p < 0.003, OR = 14.5). However, no significant association was observed between the functional oipA status and atrophy gastritis (p < 0.05). The study showed there to be a high frequency of detection of genes of the pathogenicity island among H. pylori DNA samples with an "on" status of the oipA gene. There was a significant correlation between an "on" status of the oipA gene and the presence of all studied cagPAI genes; the highest correlation was found for the cagT and cagM genes. The link between the functional status of the oipA gene and other virulence factors encoded by the pathogenicity island cagPAI is important in the pathogenesis of H. pylori and requires further investigation. [ABSTRACT FROM AUTHOR]

This paper describes an experiment on focusing a proton beam with an energy of 50 GeV on the U‑70 accelerator using a crystal device. The focusing device is based on the use of bending a plane-parallel silicon wafer in which the side faces are rotated relative to the crystallographic planes by a small angle. The beam is focused at a distance of 10 cm into a narrow line with a width of FWHM ~7 μm. The prospects for using such a short-focus device on modern accelerators are described. [ABSTRACT FROM AUTHOR]

A modification of the LENS (Low Energy Neutrino Spectroscopy) project for spectroscopy of solar neutrinos with energies above about 715 keV on the basis of new technologies and solutions is examined. The respective detector employs In nuclei as a target for neutrinos. The creation of a detector containing about 200 t of a scintillator loaded with 10 t of indium will make it possible to measure, within five years, the energy spectra of solar neutrinos from Be, neutrinos from the CNO cycle, and neutrinos with small systematic errors. The detector was simulated in the form of a set of cells of a liquid scintillator doped with indium (about 10 in weight). Necessary technical conditions for detector cells are formulated, and the possible counting rate for events induced by internal and external backgrounds and characterized by an energy release of 600 to 1600 keV is estimated. It is shown that such a detector is implementable, in principle. [ABSTRACT FROM AUTHOR]

Aims: To examine: (1) a motivational pathway where head nurse proactive leadership and nurse vigour are linked, which in turn correlates to missed nursing care, and might be moderated by workload; and (2) an energetic pathway where workload and nurse exhaustion are linked, which in turn correlates to missed nursing care, and might be moderated by head nurse proactive leadership. Design: A cross‐sectional design, with nurses nested in wards. Methods: During 2018, 196 nurses from 37 wards completed questionnaires that included the 22‐item MISSCARE survey; the 6‐item Work Demand subscale; the 10‐item Proactivity Personality scale; the 5‐item Exhaustion subscale of the Maslach Burnout Inventory; the 5‐item Vigour subscale of the Work Engagement scale; and nurse's and head nurse's sociodemographic characteristics. Moderation‐mediation models were performed using mixed‐linear model analyses. Results: A moderation‐mediation motivational pathway was supported. Specifically, nurse vigour was higher under low workload when head nurse proactive leadership was high (β = −.09, p =.050), which in turn was associated with lower missed nursing care (β = −.10, p =.045). Yet, a moderation‐mediation energetic pathway was not supported. Specifically, nurse exhaustion was lower under low workload when head nurse proactive leadership was high (β =.14, p =.032), but no association was found between exhaustion and missed nursing care. Conclusions: This study shows that there is a significant role for nurse agency and nurse ability to cope with scarce resources. Impact: To date, research has focused mainly on the assumption that missed nursing care is a result of scarce resources. Findings indicate that even under scarce resources, nurses can be motivated to reduce missed nursing care. Emphasis should be placed on promoting and maximizing nurse motivation. This can be achieved by developing and implementing interventions of proactive leadership of head nurses. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic outbreak had a negative impact on kindergarten activities. These young children, who had been compelled to stay home during lockdowns, suffered a lack of movement and loss of mobility, resulting in deteriorated physical motor skills. Lack of sufficient motor experience in early childhood can impair children's motor and cognitive development. Balance skills are fundamental to all other motor abilities, from the most basic movements to the most complex motor skills. The purpose of this study was to implement a short-term physical activity program, which may have a direct effect on children's fundamental balance ability. Ninety-six kindergarten children (45 boys and 51 girls), aged 4–6 years, participated in the study. Data were analyzed using three-way ANOVA and interaction analyses. The results suggest that short, focused, and dedicated balance training programs have a beneficial influence on the static balance of preschoolers and can mitigate some of the negative physical outcomes of lockdowns. In conclusion, this study indicates that a short-term physical training program had a positive effect on the motor abilities of preschoolers after COVID-19-related lockdowns. More research is needed in order to fully understand the complete impact of the worldwide health crisis and the best ways in which to address it. [ABSTRACT FROM AUTHOR]

We consider the process of tokenization of credits in the peer-to-peer lending model. The investor risk is formulated in terms of reliability theory. This allows us to write restrictions on the parameters of the token package that provide a given risk and profitability for the known parameters of the loan portfolio. [ABSTRACT FROM AUTHOR]

We consider the problem of minimizing the risk taken on by investors in a two-tier (banking) system of lending and a system of peer-to-peer lending, assuming the incoming risks to be constant. It is shown that with the introduction of a special (nonsystematic) risk, the peer-to-peer lending model turns out to be optimal. [ABSTRACT FROM AUTHOR]

The paper deals with the phylogenetic and functional microbial diversity in the samples of umbric luvisol contaminated and uncontaminated with hydrocarbons and of urban stratozem. High-throughput sequencing of the V3–V4 region of the 16S rRNA gene revealed predomination of bacteria of the phyla Proteobacteria, Actinobacteria, and Acidobacteria in the studied soil samples. Bacteria of the genera Sphingomonas, Bradyrhizobium, and Pseudolabrys in the samples of umbric luvisol and bacteria of the genera Brevundimonas, Stenotrophomonas, and Streptomyces in urbostratozem had the greatest potential functional activity in conversion of nitrogen compounds, degradation of chloroalkanes, chloroalkenes, and benzoate. Strains of Stenotrophomonas maltophilia, which degraded oil, petroleum products, and polycyclic aromatic hydrocarbons (PAHs, phenanthrene, anthracene, and pyrene) were isolated from oil-contaminated soils. Under microcosm conditions, microorganisms of umbric luvisol efficiently degraded various components of naphthenic-methane and methane-naphthenic oil. While the content of aromatic components in naphthenic-methane oil degraded by the soil microbial community and by the community enriched with S. maltophilia strain P420c was almost the same, in the variant with bioaugmentation the degradation process of these components proceeded 14 days faster. The enrichment of soil with specific degraders of PAHs and aromatic compounds may be appropriate for the soils of northern regions with a low duration of the summer period, which are polluted with oil with a high content of aromatic and asphalt-resinous compounds. [ABSTRACT FROM AUTHOR]

Metal β-diketonates and carboxylates have been studied with the aim to use them in element-containing liquid organic scintillators. Their effect on the light yield and transparency of scintillators has been studied. Absorption spectra of neodymium and zirconium β-diketonates and neodymium and gadolinium 3,5,5-trimethylhexanoates have been reported. In terms of specific light yield of scintillators with added β-diketonates and carboxylates, it has been concluded that the high values of specific light yield at large concentrations of β-diketonates (50%) can be achieved only on addition of considerable amounts of scintillation additives (up to 100 g/L). The stability of metal-containing scintillators related to the structure of added compounds, purity of all components of scintillator, and effect of metal carboxylates and β-diketonates on alkylbenzene oxidation have been studied. [ABSTRACT FROM AUTHOR]

A radiation monitor based on a cast polystyrene scintillator with wavelength-shifting optical fibers is described, which has a large aperture; the dimensions of the active part of the detector are 100 × 200 × 5 cm. The monitor also includes a sensor for the presence of a monitored object and a television camera, united by a single control system. The monitor is designed to control transportation of radioactive materials. The operating experience is described. [ABSTRACT FROM AUTHOR]

Purpose: Heat intolerance (HI) is determined in the Israel Defense Force according to a heat tolerance test (HTT) before returning to duty after an exertional heat stroke (EHS) event. Recently, increased numbers of female combatants resulted in an increased number of EHS cases among women and a higher percentage of heat intolerance (HI) individuals. We aimed to evaluate the differences between tolerance to heat among women performing an HTT in relation to their menstrual cycle phase. Method: Thirty-three female participants were sorted into two groups: HI and heat tolerant (HT) according to two HTTs performed during both the luteal and follicular phases of the menstrual cycle or while consuming and during a break from consuming contraceptives. Results: HT women had an 18% higher maximal oxygen uptake (p < .005, 95% CI [2.6,9.8]) and 1.2% lower skin temperature in the HTT at the during and follicular phases (p < .01, 95% CI [0.12,0.77]) and 1.7% lower at the off and luteal phases (p < .001, 95% CI [0.34,0.92]). The mean sweat rate was 14% lower among the HI group only at the HTT at the during and follicular phases (p < .05, 95% CI (3,88)]). Conclusion: We found that HT can be predicted using aerobic capacity and core body temperature. Moreover, during the luteal phase, women presented altered thermoregulation that decreased the probability of being HT. This emphasizes the importance of considering the HT/HI criteria in the HTT for women, according to their aerobic ability and menstrual-cycle phase. [ABSTRACT FROM AUTHOR]

Zirconium β-diketonates (synthesized dipivaloylmethanate and commercially available acetylacetonate) have been studied to obtain low-background Zr-containing liquid organic scintillators. Their solubility in organic solvents—linear alkylbenzene and pseudocumene—has been studied. Light absorption in pseudocumene and hexane and specific light yield of scintillator with added β-diketonates depending on zirconium concentration and scintillation additives has been measured. It has been shown that the specific light yield of scintillator has a high value (>60%) only at low zirconium concentration (not higher 2.5 g/L). [ABSTRACT FROM AUTHOR]

In view of the successful experience in the generation of pion and kaon secondary beams using a focusing crystal, it has been proposed to build at the U-70 accelerator a new-type channel of secondary particles that does not consume electric power. It has been shown experimentally that an extraction septum magnet can be protected from radiation by applying a multistrip crystal device through current septum shadowing by the crystal that involves the bulk reflection regime for the deflection of particles. The listed applications of crystals are novel in the world practice with accelerators. [ABSTRACT FROM AUTHOR]

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An amendment to this paper has been published and can be accessed via the original article. [ABSTRACT FROM AUTHOR]

It is well-established that physical exercise in humans improves cognitive functions, such as executive functions, pattern separation, and working memory. It is yet unknown, however, whether spatial learning, long known to be affected by exercise in rodents, is also affected in humans. In order to address this question, we recruited 20 healthy young male adults (18–30 years old) divided into exercise and control groups (n = 10 in each group). The exercise group performed three sessions per week of mild-intensity aerobic exercise for 12 weeks, while the control group was instructed not to engage in any physical activity. Both groups performed maximal oxygen uptake (VO2max) tests to assess their cardiovascular fitness at baseline and every 4 weeks through the 12 weeks of the training program. The effects of mild aerobic exercise were tested on performance in two different virtual reality (VR)-based spatial learning tasks: (1) virtual Morris water maze (VMWM) and (2) virtual Radial arm water maze (VRAWM). Subjects were tested in both tasks at baseline prior to the training program and at the end of 12 weeks training program. While the mild-intensity aerobic exercise did not affect subjects' VO2max parameters, mean time to anaerobic threshold increased for the exercise group compared with control. No effect was observed, however, on performance in the VMWM or VRAWM between the two groups. Based on these results, we suggest that mild-intensity aerobic exercise does not improve spatial learning and memory in young, healthy adults. [ABSTRACT FROM AUTHOR]

The surface-enhanced Raman spectroscopy (SERS) signal of a reporter on silver nanoparticles can be effectively gained by gradient electric field application. The external electric field initiates the dielectrophoresis of nanoparticles and their electrically induced dipole–dipole interaction. Owing to dielectrophoresis, the nanoparticles are concentrated in the area of high electrical field strength. The induced dipole–dipole interaction leads to additional coagulation of nanoparticles and formation of hotspots. Both dielectrophoresis and induced dipole–dipole interaction increase the number of hotspots, which leads to a SERS signal growth. These two mechanisms of SERS signal amplification are explained by the dielectrophoresis and Derjaguin–Landau–Verwey–Overbeek theories. The benefits of the surface-enhanced Raman spectroscopy in tandem with the gradient electric field are experimentally confirmed using a SERS-active reporter, 4-mercaptophenylboronic acid which has a characteristic peak at Raman shift of 1586 cm−1, conjugated to silver nanoparticles of 32, 52, 58, and 74 nm in diameter. The SERS signal gain depends on the silver nanoparticle stability, size, and electric field strength. The limit of detection for 4-mPBA in the system under study can be calculated from the concentration plot and equals to 63 nM. The enhancement factor calculated for SERS in tandem with the gradient electric field can reach 106. Graphical abstract [ABSTRACT FROM AUTHOR]

A multistage collimation system for the absorption of the growing halo of circulating beams is used at the Large Hadron Collider (LHC) to protect superconducting magnets and to ensure their reliable operation. A similar system is also planned for the Future Circular Collider (FCC). Studies for the improvement of the collimation system are performed prior to the operation of the LHC with a high luminosity. Studies have shown that one of the solutions to improve the beam collimation is the use of channeling in a short bent crystal, which serves as a primary collimator throwing particles deep into the secondary collimator by means of channeling. This system is very sensitive to the angular position of the crystal and various possible vibrations. In this work, another approach to beam collimation based on the bulk reflection of particles from bent crystal-lographic planes in a sequence of crystals has been proposed. Advantages of this scheme have been justified and a multistrip crystal device has been proposed to implement this scheme. [ABSTRACT FROM AUTHOR]

Sicoli & Holton (2014) (PLoS ONE 9:3, e91722) use computational phylogenetics to argue that linguistic data from the putative, but likely, Dene-Yeniseian macro-family are better compatible with a homeland in Beringia (i.e., northeastern Siberia plus northwestern Alaska) than with one in central Siberia or deeper Asia. I show that a more careful examination of the data invalidates this conclusion: in fact, linguistic data do not support Beringia as the homeland. In the course of showing this, I discuss, without requiring a deep mathematical background, a number of methodological issues concerning computational phylogenetic analyses of linguistic data and drawing inferences from them. The aim is to contribute to making computational phylogenetics less of a black box for historical linguists. I conclude with a brief overview of the current evidence bearing on the Dene-Yeniseian homeland from linguistics, archaeology, folklore studies and genetics, and suggest current best practice for linguistic phylogenetics, the use of which would have helped to avoid some of the problems in Sicoli and Holton's Dene-Yeniseian study, and in turn the percolation of those problems into subsequent synthetic interdisciplinary research. [ABSTRACT FROM AUTHOR]

Background: A walking blood bank (WBB) refers to the use of fellow combatants for battlefield blood donation. This requires pretesting combatants for infectious diseases and blood type. A fundamental prerequisite for this technique is that the donating soldier will suffer minimal physiological and mental impact. The purpose of the current study is to assess the effect of blood shedding on battlefield performance.Methods: This is a double-blind randomized control trial. Forty Israel Defense Forces combatants volunteered for the study. Participants underwent baseline evaluation, including repeated measurement of vital signs, cognitive evaluation, physical evaluation, and a strenuous shooting test. Three weeks after the baseline evaluation, subjects were randomized to either blood donation or the control group. For blinding purposes, all subjects underwent venous catheterization for the duration of a blood donation. Repeated vital signs and function evaluation were then performed.Results: Thirty-six patients were available for randomization. Baseline measurements were similar for both groups. Mean strenuous shooting score was 80.5 ± 9.5 for the control group and 82 ± 6.6 for the test group (p = 0.58). No clinically or statistically significant differences were found in tests designed to evaluate cognitive performance or physical functions. Vital signs taken multiple times were also similar between the test and control groups.Conclusions: Executive, cognitive, and physical functions were well preserved after blood donation. This study supports the hypothesis that a WBB does not decrease donor combat performance. The categorical prohibition of physical exercise following blood donation might need to be reconsidered in both military and civilian populations. [ABSTRACT FROM AUTHOR]

The participation of women in physically strenuous athletic and occupational tasks has increased substantially in the past decade. Female sex steroids have influences on thermoregulatory processes that could impact physical performance in the heat. Here, we summarize and evaluate the current literature regarding sex differences in thermoregulation and provide recommendations for heat-illness risk-mitigation strategies. [ABSTRACT FROM AUTHOR]

Objective: Researchers have produced a hypothesis of transient heat intolerance (HI) after exertional heat stroke (EHS). Based on this hypothesis, heat-tolerance testing (HTT) has been postponed until weeks 6 to 8 after EHS and other types of exertional heat illness (EHI). We compared the HTT results of participants after either EHS or other EHI who were tested earlier (≤6-week group) versus those who were tested later (>6-week group) to verify the hypothesis. Design: Cohort study. Setting: Data obtained from records of military athletes who experienced EHS or EHI. Patients or Other Participants All participants: who underwent HTT after EHI or EHS experienced between 2014 and 2018 and for whom complete data regarding the severity of the event (rectal temperature, neurologic symptoms, and laboratory results) and HTT results were available were included. Participants with suspected EHS and those with other EHIs were evaluated separately. Main Outcome Measure(s): The percentages of participants with HI and mean probability of heat tolerance were compared between those tested within 6 weeks of the event and those tested later. Results: A total of 186 participants were included in this study (EHS: 12 in the <6-week group, 9 in the >6-week group; EHI: 94 in the <6-week group, 71 in the >6-week group). In the EHS group, the percentages with HI (33% versus 44%, P = .67) and mean probability of heat tolerance (0.82 versus 0.82, P = .98) did not differ. In the EHI group, participants who were tested after 6 weeks had a greater chance of being diagnosed with HI (38% versus 21.3%, P < .02) Conclusions: The HTT results were similar between participants with EHS who were tested early (<6 weeks) and those tested late (>6 weeks). Further investigation of heat-tolerance changes in larger cohorts of patients after EHS is required to verify the theory of transient HI. [ABSTRACT FROM AUTHOR]

For the work with polynomials such data representations as lists of terms, geobuckets, and heaps are usually used. In this paper, an attempt to give a new look on the representation of polynomials for computing involutive and Gröbner bases of systems of nonlinear polynomial equations is made. The proposed approach makes it possible to execute a part of this computational task on the GPU, which opens prospects for solving more complicated problems. [ABSTRACT FROM AUTHOR]

Factors affecting the stability of gadolinium- and neodymium-loaded liquid organic scintillators intended for use in large-scale experimental facilities for neutrino physics and astrophysics are examined. The effect of composition (type and structural formula of gadolinium and neodymium compounds) on the optical properties of such scintillators is analyzed. It is shown that the oxidation of alkylbenzenes is one of the reasons for the degradation (decrease in transparency) of the scintillators. Gadolinium and neodymium compounds may be catalysts for the oxidation processes. [ABSTRACT FROM AUTHOR]

We present the experimental observation of the reduction of multiple scattering of high-energy positively charged particles during channeling in single crystals. According to our measurements the rms angle of multiple scattering in the plane orthogonal to the plane of the channeling is less than half that for non-channeled particles moving in the same crystal. In the experiment we use focusing bent single crystals. Such crystals have a variable thickness in the direction of beam propagation. This allows us to measure rms angles of scattering as a function of thickness for channeled and non-channeled particles. The behaviour with thickness of non-channeled particles is in agreement with expectations whereas the behaviour of channeled particles has unexpected features. [ABSTRACT FROM AUTHOR]

Context: The heat-tolerance test (HTT) is a screening tool for secondary prevention of exertional heat illness by the Israel Defense Forces. To discern participant tolerance, recruits are exposed to intermediate environmental and exercise stresses, and their physiological responses, core temperature, and heart rate are monitored. When their physiological measures rise at a higher rate or exceed the upper levels of absolute values compared with other participants, heat intolerance (HI) is diagnosed. Objective: To develop a mathematical model to interpret HTT results and provide a quantitative estimate of the probability of heat tolerance (PHT). Design: Cross-sectional study. Setting: Warrior Health Research Institute. Patients or Other Participants: The HTT results of 175 random individuals tested after an episode of exertional heat illness were classified qualitatively and then divided into training (n = 112) and testing (n = 63) datasets. All individuals were male soldiers (age range = 18-22 years) who had sustained an episode of definitive or suspected exertional heat stroke. Main Outcome Measure(s): Based on the decision algorithm used by the Israel Defense Forces for manual interpretation of the HTT, we designed a logistic regression model to predict the heat-tolerance state. The model used a time series of physiological measures (core temperature and heart rate) of individuals to predict the manually assigned diagnosis of HT or HI. It was initially fitted and then tested on 2 separate, random datasets. The model produced a single value, the PHT, and its predictive ability was demonstrated by prediction-density plots, receiver operating characteristic curve, contingency tables, and conventional screening test evaluation measures. Results: According to prediction-density plots of the testing set, all HT patients had a PHT of 0.7 to 1. The receiver operating characteristic curve plot showed that PHT was an excellent predictor of the manual HT interpretations (area under the curve = 0.973). Using a cutoff probability of 0.5 for the diagnosis of HI, we found that PHT had sensitivity, specificity, and accuracy of 100%, 90%, and 92.06%, respectively. Conclusions: The PHT has the potential to be substituted for manual interpretation of the HTT and to serve in a variety of clinical and research applications. [ABSTRACT FROM AUTHOR]

In recent years, an increasing research interest has been seen in the clinical consequences of hamstring-muscle injuries in sports. Yet the literature is lacking on hamstring flexibility and it correlations with physical performance and injury risk-factors, especially among young basketball players. The aim of this study, therefore, was to examine the relationships between hamstring flexibility, physical performance, and injuries among young basketball players. The study, which was conducted during 2022- 2023, including 114 basketball players aged 12-17 years. Anthropometric data, hamstring flexibility test results, and physical performance data were collected. A positive correlation was seen between hamstring flexibility and physical performance. However, no correlation was found between hamstring flexibility and injury prevalence and/or visits to a physician. The findings of this study emphasize the importance of including flexibility exercises in basketball training programs, as a means for maximizing performance and possibly preventing injuries. [ABSTRACT FROM AUTHOR]

Walkden and Breitbarth employ historical data in order to test a conjecture expressed by Trudgill (2011) regarding a link between linguistic complexity and the language-contact situation: namely, "short-term contact involving extensive adult second-language (L2) use is predicted to lead to simplification" (W&B). Drawing on L2 research in the generative tradition, W&B use a specific theoretical concept supposed to faithfully capture L2-difficulty: Interpretability Hypothesis, which states that (assuming a broadly Minimalist-Framework analysis) uninterpretable features are not easily available to L2-learners. And, in order to connect uninterpretable features with Trudgill's conjecture in the way the authors do, we need a difficulty that only arises with the presence of L2 learners. [Extracted from the article]

The aim of this study was to evaluate the prevalence of Helicobacter pylori genotypes (vacA and cagPAI) directly in gastric biopsy specimens in patients with gastric diseases in Belarus. Gastric biopsies were collected from 461 patients with different gastrointestinal disorders: superficial gastritis (287 subjects), atrophy gastritis (59 subjects), erosive gastritis (47 subjects), duodenal ulcer disease (54 subjects), and stomach ulcer (14 subjects). PCR-based genotyping was used to detect s1a, s1b, s2, m1a, m1b, m2, cagM, cagA, and cagT genes. Overall prevalence of vacA s1a allele was 60.5% followed by m2 (47.1%) and m1a (37.5%). The analysis of data showed that genotype s1a / m1a was significantly more prevalent in patients with duodenal ulcer (21.4% vs. 45.1%, OR = 3.0, 95% CI = 1.5–6.1). The cagA gene was found with a high incidence in most patients with inflammatory diseases of stomach and duodenum. There was a significant increase in the frequency of cagT in patients with duodenal ulcer as compared to superficial gastritis. A high cagM prevalence was found in patients with atrophy gastritis and duodenal ulcer disease. All three island genes of pathogenicity of cagPAI are more often detected in patients with duodenal ulcer, which increases the risk of developing duodenal ulcer by 4.5 times. [ABSTRACT FROM AUTHOR]

The generation of beams of secondary particles (π and K mesons) at proton accelerators is a difficult scientific and engineering problem. To obtain narrow directional particle beams for experiments, intense extracted proton beams are used, secondary particles (π and K mesons) are generated at an external target, and they are focused and transferred through long magneto-optical channels. In this work, a surprisingly simple method based on a crystal focusing device has been proposed to obtain secondary beams. An experiment on the production of a secondary beam using a crystal has been performed at the U-70 accelerator. Schemes for the formation of beams with energies E ~ 1 TeV have been proposed for large colliders such as the Large Hadron Collider. [ABSTRACT FROM AUTHOR]