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The COVID-19 pandemic has led to a global crisis resulting in lockdowns worldwide. Studies found that these could amplify negative affects predictive of disturbances in time perception. However, all existing studies on this topic concentrated on the general population during a lockdown at home. There was no research on university students living in dormitories. This study fills a gap in the literature by investigating the affective states and awareness of the passage of time of Chinese university students during an exceptional dormitory lockdown. Using a snowball sampling approach, this web-based study recruited 225 volunteers (136 girls, 17-27 years old) during a dormitory lockdown. The online survey consisted of questions on demographic information, affective states (the Chinese version of the depression anxiety stress scales-21 (DASS-21) on depression, anxiety, and stress), and sense of the passage of time (the translated version of the assessment of passage of time over daily, weekly and yearly periods). The researchers shared the questionnaire link via the social media application WeChat. The study applied descriptive statistics and column charts to represent students' affective states and sense of the passage of time under extreme conditions and Pearson's correlation analysis to examine the impact of affective states on their sense of time. The study's results indicate that the dormitory lockdown caused a significant increase in all depression, anxiety, and stress categories of the DASS-21, as well as a distortion of the sense of time passing. However, the direction of the distortion differed from that in previous studies. Moreover, a Pearson correlation analysis showed that none of the three negative affects could be associated with students' sense of time. The findings of this study indicate an increased vulnerability of students due to the lockdown. Their emotions were strongly affected, requiring particular interventions to preserve their mental well-being. In addition, they showed a different distortion direction of time passage. Finally, they differed in the correlations between negative affect and the sense of passage of time compared to the general population in lockdown at home. This shows a need to investigate the impact of psychological states on students' routines and quality of life in emergencies. This study's scope should be expanded by incorporating additional factors pertaining to the passage of time and by integrating cross-cultural comparisons.

Introduction: There is a high morbidity and mortality rate in mechanical trauma (MT)-induced hepatic injury. Currently, the molecular mechanisms underlying liver MT are largely unclear. Exploring the underlying mechanisms and developing safe and effective medicines to alleviate MT-induced hepatic injury is an urgent requirement. The aim of this study was to reveal the role of mitochondria-associated ER membranes (MAMs) in post-traumatic liver injury, and ascertain whether melatonin protects against MT-induced hepatic injury by regulating MAMs. Methods: Hepatic mechanical injury was established in Sprague–Dawley rats and primary hepatocytes. A variety of experimental methods were employed to assess the effects of melatonin on hepatic injury, apoptosis, MAMs formation, mitochondrial function and signaling pathways. Results: Significant increase of IP3R1 expression and MAMs formation were observed in MT-induced hepatic injury. Melatonin treatment at the dose of 30 mg/kg inhibited IP3R1-mediated MAMs and attenuated MT-induced liver injury in vivo. In vitro, primary hepatocytes cultured in 20% trauma serum (TS) for 12 h showed upregulated IP3R1 expression, increased MAMs formation and cell injury, which were suppressed by melatonin (100 μmol/L) treatment. Consequently, melatonin suppressed mitochondrial calcium overload, increased mitochondrial membrane potential and improved mitochondrial function under traumatic condition. Melatonin's inhibitory effects on MAMs formation and mitochondrial calcium overload were blunted when IP3R1 was overexpressed. Mechanistically, melatonin bound to its receptor (MR) and increased the expression of phosphorylated ERK1/2, which interacted with FoxO1 and inhibited the activation of FoxO1 that bound to the IP3R1 promoter to inhibit MAMs formation. Conclusion: Melatonin prevents the formation of MAMs via the MR-ERK1/2-FoxO1-IP3R1 pathway, thereby alleviating the development of MT-induced liver injury. Melatonin-modulated MAMs may be a promising therapeutic therapy for traumatic hepatic injury. [ABSTRACT FROM AUTHOR]

Aim: Under hypobaric hypoxia (HH), the heart triggers various defense mechanisms including metabolic remodeling against lack of oxygen. Mitofusin 2 (MFN2), located at the mitochondrial outer membrane, is closely involved in the regulation of mitochondrial fusion and cell metabolism. To date, however, the role of MFN2 in cardiac response to HH has not been explored. Methods: Loss‐ and gain‐of‐function approaches were used to investigate the role of MFN2 in cardiac response to HH. In vitro, the function of MFN2 in the contraction of primary neonatal rat cardiomyocytes under hypoxia was examined. Non‐targeted metabolomics and mitochondrial respiration analyses, as well as functional experiments were performed to explore underlying molecular mechanisms. Results: Our data demonstrated that, following 4 weeks of HH, cardiac‐specific MFN2 knockout (MFN2 cKO) mice exhibited significantly better cardiac function than control mice. Moreover, restoring the expression of MFN2 clearly inhibited the cardiac response to HH in MFN2 cKO mice. Importantly, MFN2 knockout significantly improved cardiac metabolic reprogramming during HH, resulting in reduced capacity for fatty acid oxidation (FAO) and oxidative phosphorylation, and increased glycolysis and ATP production. In vitro data showed that down‐regulation of MFN2 promoted cardiomyocyte contractility under hypoxia. Interestingly, increased FAO through palmitate treatment decreased contractility of cardiomyocyte with MFN2 knockdown under hypoxia. Furthermore, treatment with mdivi‐1, an inhibitor of mitochondrial fission, disrupted HH‐induced metabolic reprogramming and subsequently promoted cardiac dysfunction in MFN2‐knockout hearts. Conclusion: Our findings provide the first evidence that down‐regulation of MFN2 preserves cardiac function in chronic HH by promoting cardiac metabolic reprogramming. [ABSTRACT FROM AUTHOR]

The COVID‐19 pandemic has led to a global crisis resulting in lockdowns worldwide. Studies found that these could amplify negative affects predictive of disturbances in time perception. However, all existing studies on this topic concentrated on the general population during a lockdown at home. There was no research on university students living in dormitories. This study fills a gap in the literature by investigating the affective states and awareness of the passage of time of Chinese university students during an exceptional dormitory lockdown. Using a snowball sampling approach, this web‐based study recruited 225 volunteers (136 girls, 17−27 years old) during a dormitory lockdown. The online survey consisted of questions on demographic information, affective states (the Chinese version of the depression anxiety stress scales‐21 (DASS‐21) on depression, anxiety, and stress), and sense of the passage of time (the translated version of the assessment of passage of time over daily, weekly and yearly periods). The researchers shared the questionnaire link via the social media application WeChat. The study applied descriptive statistics and column charts to represent students' affective states and sense of the passage of time under extreme conditions and Pearson's correlation analysis to examine the impact of affective states on their sense of time. The study's results indicate that the dormitory lockdown caused a significant increase in all depression, anxiety, and stress categories of the DASS‐21, as well as a distortion of the sense of time passing. However, the direction of the distortion differed from that in previous studies. Moreover, a Pearson correlation analysis showed that none of the three negative affects could be associated with students' sense of time. The findings of this study indicate an increased vulnerability of students due to the lockdown. Their emotions were strongly affected, requiring particular interventions to preserve their mental well‐being. In addition, they showed a different distortion direction of time passage. Finally, they differed in the correlations between negative affect and the sense of passage of time compared to the general population in lockdown at home. This shows a need to investigate the impact of psychological states on students' routines and quality of life in emergencies. This study's scope should be expanded by incorporating additional factors pertaining to the passage of time and by integrating cross‐cultural comparisons. Practitioner Points: 1.The dormitory lockdown caused a significant increase in all depression, anxiety, and stress categories of the DASS‐21.2.The dormitory lockdown caused a distortion of the sense of time passing, which differed from that in previous studies.3.None of the three negative affects could be associated with students' sense of time. [ABSTRACT FROM AUTHOR]

This paper presents a new topology named zero-voltage switching (ZVS) resonant reset dual switch forward dc-dc converter, which, compared with resonant reset single switch forward dc-dc converter, maintains the advantage that duty cycle can be more than 50%, at the same time disadvantages of high voltage stress for main switches and low efficiency are overcome. In addition, ZVS is achieved for all switches of the presented topology. Therefore, this proposed topology is very attractive for high voltage input, wide range, and high efficiency applications. In this paper, the operation principle and characteristic of this topology are analyzed in detail. Next, the design consideration is presented. Finally, the advantages mentioned above are verified by experimental results. Index Terms--Zero-voltage switching (ZVS).

The performance of reinforced concrete (RC) columns plays a crucial role in the overall performance of framed structures and RC bridges. Therefore, the deformation limits associated with the performance of RC columns constitute an important part in the performance criteria for structural systems. On the other hand, it is possible to analytically correlate qualitative performance descriptions to quantitative design parameters such as curvature and drift at the column level. In this paper, probabilistic drift limits of RC columns at three distinctive performance levels are investigated by means of Monte Carlo simulation of the sectional curvature in conjunction with a statistical model of the plastic hinge length. A simple methodology is then introduced to evaluate the performance reliability of different column designs by constructing the fragility curves. With a generic single degree of freedom system consisting of a particular column, the probabilistic drift demands are derived from the displacement response spectra (DRS). The probability distributions of the DRS are established from a large set of ground motion records. Results of fragility curves demonstrate that increasing the flexural strength of a column does not significantly enhance its performance reliability during a probable earthquake; as a result, a design with higher flexural strength and lower ductility could be less reliable than a comparable lower strength and higher ductility design. DOI: 10.1061/(ASCE)0733-9445(2005)131:6(966) CE Database subject headings: Probabilistic models; Drift; Reliability; Performance evaluation; Concrete columns.