Gene regulation during meiosis.

Meiosis is essential for gamete production in all sexually reproducing organisms. It entails two successive cell divisions without DNA replication, producing haploid cells from diploid ones. This process involves complex morphological and molecular differentiation that varies across species and between sexes. Specialized genomic events like meiotic recombination and chromosome segregation are tightly regulated, including preparation for post-meiotic development. Research in model organisms, notably yeast, has shed light on the genetic and molecular aspects of meiosis and its regulation. Although mammalian meiosis research faces challenges, particularly in replicating gametogenesis in vitro, advances in genetic and genomic technologies are providing mechanistic insights. Here we review the genetics and molecular biology of meiotic gene expression control, focusing on mammals.

Switchable Power Generation in Triboelectric Nanogenerator Toward Chip-Less Wearable Power Module Applications.

A conceptual shift toward next-generation wearable electronics is driving research into self-powered electronics technologies that can be independently operated without plugging into the grid for external power feeding. Triboelectric nanogenerators (TENGs) are emerging as a key component of self-powered electronics, but a power type mismatch between supply and demand limits their direct implementation into wearable self-powered electronics. Here, a TENG with switchable power mode capability is reported where the charge flow direction is modulated over the course of slow and random mechanical stimuli, with exceptional rectification capabilities as high as ≈133, stable outputs over the cycles, and design flexibility in different platforms. Importantly, the remarkable switchable power generation with fabric counter materials illuminates a new path for the smooth integration of flexible TENGs into wearable self-powered electronics.

Properties and functions of acylated starch with short-chain fatty acids: a comprehensive review.

Short-chain fatty acids (SCFAs) are the primary energy source of colonic epithelial cells, but oral SCFAs are digested, absorbed, or degraded before reaching the colon. The acylated starch with SCFAs can be fermented and release specific SCFAs under the action of colonic intestinal microbiota. This review first introduces the preparation method, reaction mechanism, and substitution factors. Second, the structure, physical and chemical properties, in vitro function, and mechanism of acylated starch were expounded. Finally, the application of acylated starch in foods is introduced, and its safety is evaluated, providing a basis for the further development of acylated starch-based foods. The acylated starch obtained by different acylation types and preparation methods is different in particle, molecular, and crystal structures, leading to changes in the function and physicochemical properties. Meanwhile, acylated starch has the functional potential of targeted delivery of SCFAs to the colon, which can increase SCFAs in feces and intestine, selectively regulate the intestinal microbiota, and produce a prebiotic effect conducive to host health. The safety of acetylated starch has been supported by relevant studies, which have been widely used in various food fields and have great potential in the food industry.

Predictive role of depressive symptoms on frailty and its components in Chinese middle-aged and older adults: a longitudinal analysis.

BACKGROUND: To investigate the cross-sectional and longitudinal associations between depressive symptoms and the prevalence of frailty and its components in a nationally representative sample of middle-aged and older Chinese adults. METHOD: The China Health and Retirement Longitudinal Study (CHARLS) provided data on 2581 (after inclusion and exclusion criteria) adults aged ≥ 45 years. Every two years, face-to-face, computer-aided personal interviews (CAPI), and structured questionnaires were used to follow up with the respondents. The Chinese version of the Center for Epidemiologic Studies-Depression Scale (CES-D) was used to evaluate depressive symptoms, and the Fried criteria were used to measure frailty. The odds ratio (OR) and 95% confidence interval (CI) for the association of exposure (depressive symptoms at baseline) with the onset of the outcome (frailty and its components) in the individuals at baseline were analyzed by binary logistic regression. RESULTS: At baseline, 11.62% of participants had frailty, and 57.92% had depressive symptoms. In the cross-sectional analysis, depressive symptoms (OR = 5.222, 95%CI 3.665-7.442) were associated with frailty. In the longitudinal analysis, after adjusting for the full set of covariates among participants free of baseline frailty, depressive symptoms were significantly associated with incident frailty during the short term (OR = 2.193, 95%CI 1.324-3.631) and the long term (OR = 1.926, 95%CI 1.021-3.632). Meanwhile, depressive symptoms were associated with an increased risk of weakness (OR = 1.990, 95%CI 1.250-3.166), slowness (OR = 1.395, 95%CI 1.044-1.865), and exhaustion (OR = 2.827, 95%CI 2.150-3.719) onset during the short-term. Depressive symptoms were associated with an increased risk of exhaustion (OR = 2.869, 95%CI 2.004-4.109) onset during the long-term. CONCLUSION: Among middle-aged and older adults, depressive symptoms could predict frailty during 2 years of follow-up and 4 years of follow-up. When considering potential confounding factors, depressive symptoms were considered a predictor of weakness, slowness, and exhaustion. Interventions aimed at preventing depressive symptoms may be beneficial in reducing frailty and its components.

Enhanced chromium and nitrogen removal by constructing a biofilm reaction system based on denitrifying bacteria preferential colonization theory.

Understanding the developmental characteristics of microbial communities in biofilms is crucial for designing targeted functional microbial enhancements for the remediation of complex contamination scenarios. The strong prioritization effect of microorganisms confers the ability to colonize strains that arrive first dominantly. In this study, the auto-aggregating denitrifying bacterial Pseudomonas stutzeri strain YC-34, which has both nitrogen and chromium removal characteristics, was used as a biological material to form a stable biofilm system based on the principle of dominant colonization and biofortification. The effect of the biofilm system on nitrogen and chromium removal was characterized by measuring the changes in the quality of influent and effluent water. The pattern of biofilm changes was analyzed by measuring biofilm content and thickness and characterizing extracellular polymer substances (EPS). Further analysis of the biofilm microbiota characteristics and potential functions revealed the mechanism of strain YC-34 biofortified biofilm. The results revealed that the biofilm system formed could achieve 90.56% nitrate-nitrogen removal with an average initial nitrate-nitrogen concentration of 51.9 mg/L and 40% chromium removal with an average initial hexavalent chromium Cr(VI) concentration of 7.12 mg/L. The biofilm properties of the system were comparatively analyzed during the biofilm formation period, the fluctuation period of Cr(VI)-stressed water quality, and the stabilization period of Cr(VI)-stressed water quality. The biofilm system may be able to increase the structure of hydrogen bonds, the type of protein secondary structure, and the abundance of amino acid-like components in the EPS, which may confer biofilm tolerance to Cr(VI) stress and allow the system to maintain a stable biofilm structure. Furthermore, microbial characterization indicated an increase in microbial diversity in the face of chromium stress, with an increase in the abundance of nitrogen removal-associated functional microbiota and an increasing trend in the abundance of nitrogen transfer pathways. These results demonstrate that the biofilm system is stable in nitrogen and chromium removal. This bioaugmentation method may provide a new way for the remediation of heavy metal-polluted water bodies and also provides theoretical and application parameters for the popularization and application of biofilm systems.

The effectiveness of using situational awareness and case-based seminars in a comprehensive nursing skill practice course for undergraduate nursing students: a quasi-experimental study.

BACKGROUND: Nurses play an important role in healthcare development. The increasing demands for nurses mean that nursing schools at the undergraduate level have the responsibility to ensure patient safety and quality care through a well-designed curriculum. This research aimed to evaluate the effect of the teaching method combined with situational awareness and case-based seminars in a comprehensive nursing skills practice course on the level of self-directed learning, professional identity, academic self-efficacy, theoretical scores, practical scores, teaching satisfaction, and student competence among nursing students. METHODS: The research population comprised was of the grades of 2019 and 2020 at Wannan Medical College in Anhui Province, China (n = 169, response rate 77.88%). The observation group from grade 2020 used the teaching method combined with situational awareness and case-based seminars, whereas the control group from grade 2019 used the traditional teaching mode. General information, self-directed learning, a professional identity, and academic self-efficacy were compared between the two groups. This research used means and standard deviations, chi-square, the Shapiro-Wilk test, and an independent sample t-test for statistical analyses. RESULTS: Compared with the control group, the total scores for self-directed learning, professional identity, and academic self-efficacy were higher in the observation group (78.80 ± 7.89 vs 60.21 ± 7.44, 63.39 ± 7.87 vs 52.35 ± 7.68, and 22.31 ± 3.30 vs 21.28 ± 2.31, respectively, with P < 0.05 for all scores). More significant improvements were made in the observation group on the level of theoretical scores (81.39 ± 3.32 vs 76.28 ± 5.90) and practical scores (93.32 ± 4.70 vs 90.67 ± 5.09) (P < 0.05). Meanwhile, teaching satisfaction, which includes teaching method (66/18 vs 32/53) and teacher-student interaction (72/12 vs 34/51), and student competence, which includes team cooperation (67/17 vs 39/46), critical thinking (60/24 vs 31/54), and communication skills (67/17 vs 38/47) after the intervention (P < 0.05). There was no significant difference in social persuasion (P > 0.05). CONCLUSION: The teaching method combined with situational awareness and case-based seminars in a comprehensive nursing skills practice course has the potential to improve the level of self-directed learning, professional identity, and academic self-efficacy, and it increases theoretical scores, practical scores, teaching satisfaction, and student competence.

Anisotropic medium sensing controlled by bound states in the continuum in polarization-independent metasurfaces.

Bound states in the continuum (BICs) with infinite quality factor (Q-factor) and significant field enhancement pave the way for realizing highly sensitive optical sensors with enhanced light-matter interactions on the nanoscale. However, current optical sensing methods are difficult to discriminate between isotropic and anisotropic media from resonance spectral lines, resulting in optical sensing methods still being limited to isotropic media. In this work, we demonstrate that BICs can be realized by modulating the period of structural units to convert BICs to QBICs without changing their space group symmetry, and propose a polarization-independent metasurfaces-based realization of highly sensitive refractive index sensors for isotropic and anisotropic media as well as discrimination. We propose a metasurface of tetrameric silicon nanoboxes with C4 symmetry as structural units to achieve the conversion of BICs to QBICs by modulating the period of structural units without changing the geometry of the structure. Two QBICs modes dominated by electric toroidal dipole and magnetic toroidal dipole are identified by multipolar decomposition and electromagnetic distribution calculations. Meanwhile, we realize the refractive index detection and resolution of isotropic and anisotropic media based on polarization-independent metasurfaces combined with isotropic and anisotropic media layers. Our work provides what we believe to be a new method for realizing the fast resolution and refractive index optical sensing of isotropic and anisotropic media, and offers new ideas for the design and application of polarization-independent metasurfaces.

[Advances in synthesis of 2-phenylethanol].

2-phenylethanol (2-PE), an aromatic alcohol with a rose fragrance, is the second most widely used flavoring substance in the world. It is widely used in the cosmetic, food, and pharmaceutical industries. This paper introduces the chemical synthesis methods of 2-PE and the synthetic pathways in plants and microorganisms, summarizes the strategies to improve the microbial synthesis of 2-PE, reviews the research progress in de novo synthesis of 2-PE in microorganisms, and makes an outlook on the research prospects, aiming to provide a theoretical basis for the industrial production of 2-PE.

Attentional Bias of Individuals with Social Anxiety towards Facial and Somatic Emotional Cues in a Holistic Manner.

Attentional bias towards threatening information is a crucial factor contributing to the development and persistence of social anxiety. However, the attentional bias towards threat information and the preferential processing pattern of emotional cues in individuals with social anxiety disorder during integrated facial and physical stimuli processing remain unclear. In this study, we employed a dot-probe paradigm to investigate the attentional bias towards integrated emotions (facial-body) among students with high and low levels of social anxiety (Experiment 1). Experiments 2 and 3 examined the attentional bias of socially anxious individuals when faced with conflicting emotional cues from faces or bodies in relation to integrated emotions. The data revealed that participants both high and low levels of social anxiety participants exhibited accelerated orienting and biased attention towards facial-body emotional processing. When there was inconsistency between emotional cues from faces or bodies and integrated emotions, higher levels of social anxiety were associated with increased vigilance towards threatening faces or bodies. These findings underscore that individuals with social anxiety possess an ability to rapidly capture threatening cues during the processing of facial-body emotional stimuli while also demonstrating a tendency to avoid relying solely on facial cues by compensating through bodily cues for emotion perception.

Scalable and Efficient Generation of Mouse Primordial Germ Cell-like Cells.

Primordial germ cells (PGCs) are the founder cells of the germline. The ability to generate PGC-like cells (PGCLCs) from pluripotent stem cells has advanced our knowledge of gametogenesis and holds promise for developing infertility treatments. However, generating an ample supply of PGCLCs for demanding applications such as high-throughput genetic screens has been a limitation. Here, we demonstrated that simultaneous overexpressing 4 transcriptional factors - Nanog and three PGC master regulators Prdm1, Prdm14 and Tfap2c - in suspended mouse epiblast like cells (EpiLCs) and formative embryonic stem cells (ESCs) results in efficient and cost-effective production of PGCLCs. The overexpression of Nanog enhances the PGC regulatory network and suppresses differentiation of somatic lineages, enabling a significant improvement in the efficiency of PGCLC production. Transcriptomic analysis reveals that differentiated PGCLCs exhibit similarities to in vivo PGCs and are more advanced compared to cytokine-induced PGCLCs. These differentiated PGCLCs could be sustained over prolonged periods of culture and could differentiate into spermatogonia-like cells in vitro. Importantly, the ability to produce PGCLCs at scale, without using costly cytokines, enables biochemical and functional genomic screens to dissect mechanisms of germ cell development and infertility.

Achieving High-Rate and Stable Sodium-Ion Storage by Constructing Okra-Like NiS2/FeS2@Multichannel Carbon Nanofibers.

Transition metal sulfides (TMSs) are considered as promising anode materials for sodium-ion batteries (SIBs) due to their high theoretical capacities. However, the relatively low electrical conductivity, large volume variation, and easy aggregation/pulverization of active materials seriously hinder their practical application. Herein, okra-like NiS2/FeS2 particles encapsulated in multichannel N-doped carbon nanofibers (NiS2/FeS2@MCNFs) are fabricated by a coprecipitation, electrospinning, and carbonization/sulfurization strategy. The combined advantages arising from the hollow multichannel structure in carbon skeleton and heterogeneous NiS2/FeS2 particles with rich interfaces can provide facile ion/electron transfer paths, ensure boosted reaction kinetics, and help maintain the structural integrity, thereby resulting in a high reversible capacity (457 mA h g-1 at 1 A g-1), excellent rate performance (350 mA h g-1 at 5 A g-1), and outstanding long-term cycling stability (93.5% retention after 1100 cycles). This work provides a facile and efficient synthetic strategy to develop TMS-based heterostructured anode materials with high-rate and stable sodium storage properties.

The crosstalk between cell death and pregnancy related diseases: A narrative review.

Programmed cell death is intricately linked to various physiological phenomena such as growth, development, and metabolism, as well as the proper function of the pancreatic ß cell and the migration and invasion of trophoblast cells in the placenta during pregnancy. Traditional and recently identified programmed cell death include apoptosis, autophagy, pyroptosis, necroptosis, and ferroptosis. In addition to cancer and degenerative diseases, abnormal activation of cell death has also been implicated in pregnancy related diseases like preeclampsia, gestational diabetes mellitus, intrahepatic cholestasis of pregnancy, fetal growth restriction, and recurrent miscarriage. Excessive or insufficient cell death and pregnancy related diseases may be mutually determined, ultimately resulting in adverse pregnancy outcomes. In this review, we systematically describe the characteristics and mechanisms underlying several types of cell death and their roles in pregnancy related diseases. Moreover, we discuss potential therapeutic strategies that target cell death signaling pathways for pregnancy related diseases, hoping that more meaningful treatments will be applied in clinical practice in the future.

Accelerated Selective Li+ Transports Assisted by Microcrack-Free Anionic Network Polymer Membranes for Long Cyclable Lithium Metal Batteries.

Rechargeable Li metal batteries have the potential to meet the demands of high-energy density batteries for electric vehicles and grid-energy storage system applications. Achieving this goal, however, requires resolving not only safety concerns and a shortened battery cycle life arising from a combination of undesirable lithium dendrite and solid-electrolyte interphase formations. Here, a series of microcrack-free anionic network polymer membranes formed by a facile one-step click reaction are reported, displaying a high cation conductivity of 3.1 × 10-5 S cm-1 at high temperature, a wide electrochemical stability window up to 5 V, a remarkable resistance to dendrite growth, and outstanding non-flammability. These enhanced properties are attributed to the presence of tethered borate anions in microcrack-free membranes, which benefits the acceleration of selective Li+ cations transport as well as suppression of dendrite growth. Ultimately, the microcrack-free anionic network polymer membranes render Li metal batteries a safe and long-cyclable energy storage device at high temperatures with a capacity retention of 92.7% and an average coulombic efficiency of 99.867% at 450 cycles.

Predictive Role of Depressive Symptoms on Frailty and its Components in Chinese Middle-Aged and Older Adults: a Longitudinal Analysis.

Background: To investigate the cross-sectional and longitudinal associations between depressive symptoms and the prevalence of frailty and its components in a nationally representative sample of middle-aged and older Chinese adults. Method: The China Health and Retirement Longitudinal Study (CHARLS) provided data on 17,104 adults aged ≥ 45 years. Every two years, face-to-face, computer-aided personal interviews (CAPI), and structured questionnaires were used to follow up with the respondents. The Chinese version of the Center for Epidemiologic Studies-Depression Scale (CES-D) was used to evaluate depressive symptoms, and the Fried criteria were used to measure frailty. The odds ratio (OR) and 95% confidence interval (CI) for the cross-sectional connections among depressive symptoms and frailty and its components in the individuals at baseline were analyzed using logistic regression. A Cox proportional hazards analysis was performed using the hazard ratio (HR) and 95% confidence interval for the prospective connection between baseline depressive symptoms and frailty and its component in the participants without frailty at baseline. Results: At baseline, 11.62% of participants had frailty, and 57.92% had depressive symptoms. In the cross-sectional analysis, depressive symptoms (OR = 5.222, 95%CI 3.665-7.442) were associated with frailty. In the longitudinal analysis, after adjusting for the full set of covariates among participants free of baseline frailty, depressive symptoms were significantly associated with incident frailty during the short term [HR = 2.193 (1.324-3.631)] and the long term [HR = 1.926 (1.021-3.632)]. Meanwhile, depressive symptoms were associated with an increased risk of weakness [HR = 1.990 (1.250-3.166)], slowness [HR = 1.395 (1.044-1.865)], and exhaustion [HR = 2.827 (2.150-3.719)] onset during the short-term. Depressive symptoms were associated with an increased risk of exhaustion [HR = 2.869 (2.004-4.109)] onset during the long-term. Conclusion: Among middle-aged and older adults, depressive symptoms could predict frailty during 2 years of follow-up and 4 years of follow-up. When considering potential confounding factors, depressive symptoms were considered a predictor of weakness, slowness, and exhaustion. Interventions aimed at preventing depressive symptoms may be beneficial in reducing frailty and its components.

Characteristics of the means and methods used in soccer training / Características dos meios e métodos utilizados no treinamento de futebol / Características de los medios y métodos utilizados en el entrenamiento de fútbol

ABSTRACT Introduction The correct understanding and implementation of the tasks set by the coach for the player are achieved through a wide variety of training sessions. To date, the question of training effectiveness and the preparation of professional soccer players for matches has not been sufficiently studied. Objective Study the means and methods used in soccer training. By comparison, find out which method is most effective in achieving a positive result during the game and maintaining the players' health. Methods The study used mathematical and physical methods and comparative analysis. In the study, the main training methods in a team were considered. A comparative analysis was made between two types of individual soccer players' training to improve physical and technical parameters. Result We established which parameters influence the choice of the training scheme. The effectiveness of both training systems is proven by the statistical indicators of soccer players who train according to these methods. Conclusion The effectiveness of the training methodology chosen by a soccer player depends on his initial physical abilities and professional skills. The study's practical significance is determined by the fact that the proposed methods can be used in training professional athletes. Evidence level II; Therapeutic studies - outcomes research.

RESUMO Introdução A correta compreensão e implementação das tarefas definidas pelo treinador para o jogador é alcançada através de uma ampla variedade de sessões de treinamento. Até hoje, a questão da eficácia do treinamento e a preparação dos jogadores profissionais de futebol para os jogos não foi suficientemente estudada. Objetivo Estudar os meios e métodos utilizados no treinamento de futebol e, por comparação, descobrir qual dos métodos é mais eficaz para obter um resultado positivo durante o jogo e manter a saúde dos jogadores. Métodos O estudo utilizou métodos matemáticos e físicos, assim como análise comparativa. No decorrer do estudo, foram considerados os principais métodos de treinamento em uma equipe. Foi realizada uma análise comparativa entre dois tipos de treinamento individual de jogadores de futebol, objetivando melhorar parâmetros físicos e técnicos. Resultado Foram estabelecidos quais parâmetros influenciam a escolha do esquema de treinamento. A eficácia de ambos os sistemas de treinamento é comprovada pelos indicadores estatísticos dos jogadores de futebol que treinam de acordo com estes métodos. Conclusão A eficácia da metodologia de treinamento escolhida por um jogador de futebol depende de suas habilidades físicas iniciais e habilidades profissionais. O significado prático do estudo é determinado pelo fato de que os métodos propostos podem ser utilizados no treinamento de atletas profissionais. Evidência nível II; Estudos terapêuticos - pesquisa de resultados.

RESUMEN Introducción La correcta comprensión y ejecución de las tareas establecidas por el entrenador para el jugador se consigue a través de una amplia variedad de sesiones de entrenamiento. Hasta hoy, la cuestión de la eficacia del entrenamiento y la preparación de los futbolistas profesionales para los partidos no se ha estudiado suficientemente. Objetivo Estudiar los medios y métodos utilizados en el entrenamiento de fútbol y, por comparación, averiguar qué método es más eficaz para conseguir un resultado positivo durante el juego y mantener la salud de los jugadores. Métodos El estudio utilizó métodos matemáticos y físicos, así como análisis comparativos. En el transcurso del estudio, se consideraron los principales métodos de formación en un equipo. Se realizó un análisis comparativo entre dos tipos de entrenamiento individual de jugadores de fútbol, con el objetivo de mejorar los parámetros físicos y técnicos. Resultado Se estableció qué parámetros influyen en la elección del esquema de entrenamiento. La eficacia de ambos sistemas de entrenamiento queda demostrada por los indicadores estadísticos de los futbolistas que entrenan según estos métodos. Conclusión La eficacia de la metodología de entrenamiento elegida por un futbolista depende de sus capacidades físicas iniciales y de sus habilidades profesionales. La importancia práctica del estudio viene determinada por el hecho de que los métodos propuestos pueden utilizarse en el entrenamiento de atletas profesionales. Nivel de evidencia II; Estudios terapéuticos - investigación de resultados.