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During the operation of single-rotor helicopters, aviation accidents quite frequently occur in the form of an unintentional turn or even a yaw rotation, causing, as a rule, a ground collision. Numerous researchers of this problem consider the loss of helicopter tail-rotor effectiveness due to wind effects as one of its possible causes. There is even a special term – the Loss of Tail Rotor Effectiveness (LTE) in the foreign literature. Hence, this paper deals with an attempt to determine the capacity of an unintentional single-rotor helicopter yaw rotation occurrence due to wind effects (the impact of the main rotor on the tail rotor was not considered in this paper). To solve this issue, theoretical methods (analytical calculations and computational experiments) were used. To carry out analytical calculations and computational experiments, a mathematical model of the Mi-8MTV helicopter yaw rotation dynamics was developed, on the basis of which a software package integrating the LTE module (for modeling the dynamics of rotational yaw motion of the helicopter) and OGL (for helicopter motion visualization) was created. Analytical calculations revealed that the yaw angular acceleration value monitored in-flight during an unintentional rotation can manifest itself due to the tail rotor thrust loss in the vortex-ring state. But for the development of an unintentional rotation to angles and angular velocities recorded in real flights, that kind of tail rotor thrust loss should occur during the entire turn. In computational experiments using the mentioned above software package, conditions failed to be created for that kind of thrust loss during the entire turn. Consequently, those yaw angles and angular velocities, that occurred in flights, could not be reached. The tail rotor, when blown by the wind in the investigated range of wind velocities (from 1 to 20 m/s) does not lose its effectiveness to such an extent that an unintentional rotation cannot be stopped by means of the tail rotor.

Due to its widespread distribution, the problem of pollen allergy does not lose its relevance for practical healthcare: the variety of clinical forms, the possibility of polyvalent sensitization and pathogenetic treatment in the form of allergen-specific immunotherapy determine the importance of studying its clinical and epidemiological features.Materials and methods. A retrospective analysis of 119 discharge summaries of children with diagnoses of “Allergic rhinoconjunctivitis”, “Bronchial asthma”, “Atopic dermatitis”, occurring with clinically significant pollen sensitization, was carried out in the period 2015–2022. The prevalence, clinical features, prevailing symptoms and atopic comorbidity of patients with pollen allergy living in the Nizhny Novgorod region were assessed.Results. Pollen allergy is characterized by a variety of clinical manifestations, which are mainly represented by allergic rhinoconjunctivitis, bronchial asthma, and oral allergic syndrome. In the study, in the majority of patients, polyvalent sensitization was combined with a pronounced variety of products that provoke oral allergic syndrome. Manifestations of pollen allergies requiring seeking medical help are equally distributed among residents of Nizhny Novgorod and the region’s villages.Conclusions. Clinical and epidemiological features of the course of pollen allergy are of great interest to the practicing physician. The variety of manifestations of pollen allergies determines the need for a clinically effective treatment method, which today is ASIT. One of the needs of modern healthcare is to increase the awareness of primary care physicians about atopic diseases, incl. pollen allergy, with the aim of timely referral of patients to a specialist. Currently, allergen-specific immunotherapy is the most effective method of treating manifestations of pollen allergies.

ABSTRACT Inflammatory bowel diseases are characterized by chronic intestinal inflammation and alterations in the gut microbiota composition. Bacteroides fragilis, which secretes outer membrane vesicles (OMVs) with polysaccharide A (PSA), can moderate the inflammatory response and possibly alter the microbiota composition. In this study, we created a murine model of chronic sodium dextran sulfate (DSS)-induced intestinal colitis and treated it with B. fragilis OMVs. We monitored the efficiency of OMV therapy by determining the disease activity index (DAI) and performing histological examination (HE) of the intestine before and after vesicle exposure. We also analyzed the microbiota composition using 16S rRNA gene sequencing. Finally, we evaluated the volatile compound composition in the animals’ stools by HS-GC/MS to assess the functional activity of the microbiota. We observed more effective intestinal repair after OMV treatment according to the DAI and HE. A metabolomic study also revealed changes in the functional activity of the microbiota, with a predominance of phenol and pentanoic acid in the control group compared to the group treated with DSS and the group treated with OMVs (DSS OMVs). We also observed a positive correlation of these metabolites with Saccharibacteria and Acetivibrio in the control group, whereas in the DSS group, there was a negative correlation of phenol and pentanoic acid with Lactococcus and Romboutsia. According to the metabolome and sequencing data, the microbiota composition of the DSS-treated OMV group was intermediate between that of the control and DSS groups. OMVs not only have an anti-inflammatory effect but also contribute to the recovery of the microbiota composition.IMPORTANCEBacteroides fragilis vesicles contain superficially localized polysaccharide A (PSA), which has unique immune-modulating properties. Isolated PSA can prevent chemically induced colitis in a murine model. Outer membrane vesicles (OMVs) also contain digestive enzymes and volatile metabolites that can complement the anti-inflammatory properties of PSA. OMVs showed high therapeutic activity against sodium dextran sulfate-induced colitis, as confirmed by histological assays. 16S rRNA sequencing of fecal samples from different inflammatory stages, supplemented with comprehensive metabolome analysis of volatile compounds conducted by HS-GC/MS, revealed structural and functional alterations in the microbiota composition under the influence of OMVs. Correlation analysis of the OMV-treated and untreated experimental animal groups revealed associations of phenol and pentanoic acid with Lactococcus, Romboutsia, Saccharibacteria, and Acetivibrio.

The functional responsibilities of general practitioners (family doctors) (GPs) have changed significantly over the past decade. The number of GP functions has expanded. Despite the increasingly complex professional activities of GPs, there is no scientific evidence for the qualification characteristics of GPs expressed in knowledge, skills, abilities, and competencies in the theory and practice in training. In this regard, a study was conducted to determine the priority of GP competencies that make up the qualification characteristics of a specialist. Aim. To analyze, generalize and rationale the research results, as well as to develop preliminary guidelines for GP training. Material and methods. The information base for the study was the results of ranking competencies according to their importance in the professional activities of GPs in Russia. It was obtained during the ascertaining experiment, implemented using the Delphi method as a method of expert assessment and strategic planning of training specialists. Conclusion. The analysis of competencies developed and agreed upon by experts showed its compliance with the job functions of GPs, the requirements of the Federal State Educational Standard for the General Medical Practice (Family Medicine) and the WONCA guidelines. A summary of the study results to determine the priority of competence in GP activities showed the following: — all competencies (25) were defined as necessary and constitutive of GP qualification; — 21 competencies were considered significant and highly significant for GPs; — 4 competencies were considered as of moderate significance and below moderate significance. The analysis of the priority of competences revealed insufficient methodological support for GP training in accordance with the social order. The results obtained showed the need to continue the study within the project "Quality Management of Training of General Practitioners (Family Doctors)".

Results of experimental research and two-dimensional hydrodynamical simulations of close to critically damped microsecond timescale underwater electrical explosions of butterfly-shaped foils for six different materials are presented. Using current and voltage waveforms along with multi-frame shadow images of the shocks generated in water, the values of the specific action integral, h, were determined. It is shown that values of h can be calculated based on the average current density and that its value (within error bars) does not change in the range of current densities (0.5–1) × 108 A/cm2. The values of h were found to be consistent with those obtained for sub-microsecond underwater electrical explosions of wires made of the same material but differ from those obtained in earlier research with explosion of wires in vacuum. [ABSTRACT FROM AUTHOR]

Abstract Background Health-oriented leadership (HoL) has a positive impact on health- and work-related outcomes of employees in face-to-face settings. Increased digitization during the COVID-19 pandemic has led to many changes and increased job demands. According to current state of research, HoL in virtual teamwork is insufficiently researched. The aim of the study is to examine the experiences of virtual leaders during the COVID-19 pandemic and to identify preconditions and preventive measures for promoting HoL. Method Using a qualitative study design, semi-structured, guide-based telephone interviews were conducted with 16 German virtual leaders between May and July 2021. The collected data were inductively analyzed and interpreted using qualitative content analysis according to Mayring. Explorative analyses of differences between leaders with and without pre-pandemic experiences with virtual leadership were made. Results Results indicated that leaders, regardless of pre-pandemic experiences with virtual leadership, faced diverse challenges in implementing HoL in virtual teamwork during the COVID-19 pandemic. Virtual leaders perceived personal preconditions (e.g., leaders’ characteristics or behaviors), organizational preconditions (support by management or open-minded corporate culture), social preconditions (e.g., social support by team) and technical preconditions (e.g., sufficient technical equipment) as conducive to implementation of HoL. Almost all leaders with pre-pandemic experience identified a need for structural preventive measures, whereas almost all leaders without pre-pandemic experience reported a need for behavioral preventive measures in order to promote HoL in virtual teams. Conclusions This study suggests that implementing HoL in virtual teamwork is challenging, complex and requires adjustments in leadership behavior. Thereby, the study provides initial empirical findings for a holistic approach to HoL implementation in virtual teams, considering beneficial multilevel preconditions. Due to a limited generalization of present results, longitudinal and interventional studies will be necessary for the analysis of causal relationships in future research. In particular, a holistic research perspective in order to understand the complex, contextual interdependencies of leadership is recommended. In practice, based on a differentiated needs analysis, structural preventive measures for a holistic organizational development as well as behavioral preventive measures for ongoing personnel development are recommended.

Abstract Background Student midwives deliver care for women under challenging job demands, which may affect their mental health– thus creating a high need for health promotion. Given the lack of research addressing this topic, the aim of this study is to examine the links between stress perception, coping behaviors, work-privacy conflict, and perception of COVID-19 pandemic impact on studies of student midwives in northern Germany. Methods Data were collected using a cross-sectional online-survey at nine midwifery study sites in northern Germany from October 2022 to January 2023. 342 student midwives (response rate: 61.3%) were surveyed on stress perception, coping behaviors, work-privacy conflict, and perceived impact of the COVID-19 pandemic on their studies. Descriptive, linear regression and moderation analyses were run to test explorative assumptions. Results Results revealed that higher levels of perceived stress were reported by 13.4% of student midwives. Social support (M = 13.76, SD = 2.19) and active stress coping (M = 10.72, SD = 2.01) were identified as most prevalent coping behaviors in the present sample. It was found that work-privacy conflict was positively associated with stress perception (ß = 0.53, p =.001) and maladaptive coping behaviors (alcohol and cigarette consumption: ß = 0.14, p =.015), and negatively associated with adaptive coping behaviors (positive thinking: ß = − 0.25, p =.001, social support: ß = − 0.23, p =.001). Students with children reported significantly lower levels of social support than students without children. 55.6% of student midwives perceived a negative impact of the COVID-19 pandemic on their studies (mostly on lectures, seminars, and contact with fellow students). Conclusions Key findings highlighted moderate stress levels among student midwives during theoretical study stage. Based on current research, prevalence of high stress levels among student midwives remains unclear. Given the overall heterogeneous, limited research on student midwives’ stress perception, coping behaviors, work-privacy conflict and perceptions of COVID-19 pandemic impact on studies, implications for research are suggested, e.g. longitudinal studies at different time points and settings and interventional studies. Findings provide a starting point for implementation of workplace health promotion in theoretical and practical stages of midwifery science study programs, e.g. training courses on stress prevention and adaptive coping, and for improvement of working conditions.

Juvenile hormone plays a “status quo” role in Drosophila melanogaster larvae, preventing the untimely metamorphosis, and performs a gonadotropic function in imagoes, ensuring the ovaries’ preparedness for vitellogenesis. The decreased level of juvenile hormone results in reproductive disorders in D. melanogaster females including a delay in the oviposition onset and a fertility decrease. Another factor that can affect the insect reproduction is an infection with the maternally inherited symbiotic α-proteobacterium Wolbachia. The present study is devoted to the analysis of the expression of two juvenile hormone metabolism genes encoding enzymes of its synthesis and degradation, juvenile hormone acid O-methyltransferase ( jhamt) and juvenile hormone epoxide hydrase (Jheh1), respectively, in four wild-type D. melanogaster lines, two of them being infected with Wolbachia. Lines w153 and Bi90 were both derived from an individual wild-caught females infected with Wolbachia, while lines w153T and Bi90T were derived from them by tetracycline treatment and are free of infection. Line Bi90 is known to be infected with the Wolbachia strain wMel, and line w153, with the Wolbachia strain wMelPlus belonging to the wMelCS genotype. It was found that infection with either Wolbachia strain does not affect the expression of the studied genes. At the same time, it was shown that the w153 and w153T lines differ from the Bi90 and Bi90T lines by an increased level of the Jheh1 gene expression and do not differ in the jhamt gene expression level. Analysis of the fertility of these four lines showed that it does not depend on Wolbachia infection either, but differs between lines with different nuclear genotypes: in w153 and w153T, it is significantly lower than in lines Bi90 and Bi90T. The data obtained allow us to reasonably propose that the inter-line D. melanogaster polymorphism in the metabolism of the juvenile hormone is determined by its degradation (not by its synthesis) and correlates with the fertility level.

Climate change is the key challenge to agriculture in the XXI century. Future agricultural techniques in the Russian Federation should involve the optimization of land utilization. This optimization should apply algorithms for smart farming and take into consideration possible climate variations. Due to timely risk assessment, this approach would increase profitability and production sustainability of agricultural products without extra expenditures. Also, we should ground farming optimization not on available empirical data encompassing limited time intervals (month, year) or human personal evaluations but on the integral analysis of long-term information bodies using artificial intelligence. This article presents the results of a multivariate analysis of meteorological extremes which caused crop failures in Eastern and Western Europe in last 2600 years according to chronicle data and paleoreconstructions as well as reconstructions of heliophysical data for the last 9000 years. This information leads us to the conclusion that the current global warming will last for some time. However, subsequent climate changes may go in any direction. And cooling is more likely than warming; thus, we should be prepared to any scenario. Plant breeding can play a key role in solving food security problems connected with climate changes. Possible measures to adapt plant industry to the ongoing and expected climate changes are discussed. It is concluded that future breeding should be based on the use of highly adapted crops that have already been produced in pre-breeding programs, ready to meet future challenges caused by potential climate change.

An actual topic in higher education research today is the study of student experiences. It is believed that knowledge of educational settings, the degree of student involvement in educational and extracurricular activities, satisfaction with the quality of courses or practices offered, etc. helps to retain the student population, modernize educational programs, university campus services, etc. The study presents a new concept of student experience, corresponding to the key position of the university as an institution for the development of human and society. Research methods are conceptual analysis and conceptual design.Ideas about the “student experience” and the need to study its components are determined by the models of relations between the university and students. Currently, universities widely use the “instruction-based” and “consumer” models, and new models such as the “co-production” or “transformative learning” model are also being tested.The article examines the “anthropic” model of relations between the university and students, which 1) reflects the civilizational mission of the university; 2) is based on philosophical and anthropological ideas about the formation of an individual person as a “path” on which he/she discovers new realities (“horizons”) of personal and professional existence; 3) sets a new direction for research on student experience.A new concept of student experience is proposed, correlated with the “anthropic” model of relations between the university and students. Significant components of such experience are: “discovering others” who are carriers of a new (for the student) self-determination, thinking, worldview, and way of action; “shift of the horizon” – the discovery of new meanings, objects, transformation of consciousness (changing its schematisms and categories); mastering a new life world; overcoming the existing ways and patterns of thinking and action, personal limitations and building a new self; reflection of one’s path and “assembling oneself” through personal history.This concept of student experience will allow us to build educational practices that are adequate to the needs of active students focused on complex educational experiences – the path of discovery and transformation of consciousness and thinking