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BackgroundPhysical activity can alleviate negative emotions in college students by enhancing mood and cognitive functions. Yet, the mechanisms underlying these benefits remain unclear.PurposeThis study examines the association between physical activity and negative emotions—specifically, depression, anxiety, and stress—in college students. Additionally, we explore the mediating effects of psychological resilience and coping styles to offer theoretical and practical insights for mitigating students’ negative emotions.MethodsUsing a stratified random sampling approach, a total of 1,380 college students, from five universities in Hangzhou, Nanjing, and Wenzhou, were included in the analysis. The survey instruments included the Physical Activity Rating Scale, Connor-Davidson Resilience Scale, Simple Coping Style Scale, and Depression-Anxiety Stress Scale. The data were statistically analyzed using multivariate methods with IBM SPSS 25.0 and the PROCESS V3.3 plug-in.Results(1) College students engage in a low level of physical activity, with male students participating significantly more than female students (p

Purpose: This study aimed to screen biomarkers to predict the efficacy of programmed cell death 1 (PD-1) blockade immunotherapy combined with chemotherapy as neoadjuvant therapy for esophageal squamous cell carcinoma (ESCC). Methods: In the first stage of the study, the baseline concentrations of 40 tumor-related chemokines in the serum samples of 50 patients were measured to screen for possible biomarkers. We investigated whether the baseline concentration of the selected chemokine was related to the therapeutic outcomes and tumor microenvironment states of patients treated with the therapy. In the second stage, the reliability of the selected biomarkers was retested in 34 patients. Results: The baseline concentration of macrophage migration inhibitory factor (MIF) was negatively correlated with disease-free survival (DFS) and overall survival (OS) in patients treated with the therapy. In addition, a low baseline expression level of MIF is related to a better tumor microenvironment for the treatment of ESCC. A secondary finding was that effective treatment decreased the serum concentration of MIF. Conclusion: Baseline MIF levels were negatively correlated with neoadjuvant therapy efficacy. Thus, MIF may serve as a predictive biomarker for this therapy. The accuracy of the prediction could be improved if the serum concentration of MIF is measured again after the patient received several weeks of treatment.

The COVID-19 vaccines have been developed in a wide range of countries. This study aimed to examine factors that related to vaccination rates and willingness to be vaccinated against COVID-19 among Chinese healthcare workers (HCWs). From 3rd February to 18th February, 2021, an online cross-sectional survey was conducted among HCWs to investigate factors associated with the acceptance and willingness of COVID-19 vaccination. Sociodemographic characteristics and the acceptance of COVID-19 vaccination among Chinese HCWs were evaluated. A total of 2156 HCWs from 21 provinces in China responded to this survey (effective rate: 98.99%)), among whom 1433 (66.5%) were vaccinated with at least one dose. Higher vaccination rates were associated with older age, working as a clinician, having no personal religion, working in a fever clinic or higher hospital grade, and having received vaccine education, family history for influenza vaccination and strong familiarity with the vaccine. Willingness for vaccination was related to working in midwestern China, considerable knowledge of the vaccine, received vaccine education, and strong confidence in the vaccine. Results of this study can provide evidence for the government to improve vaccine coverage by addressing vaccine hesitancy in the COVID-19 pandemic and future public health emergencies.

In this work, the effect of Mo and Cr on microstructure and mechanical properties of newly titanium alloys (Ti–3Al–2Nb-1.2V–1Zr–1Sn-xCr-yMo) was investigated, and a composition-microstructure-properties relationship was established by diffusion multiple. The microstructure characterization (volume fraction, size of α phases) for alloys with different molybdenum equivalent (Mo[q]) was predicted by machine learning (BP neural network), and the result shows a good agreement between the predicted results and experimental values. Combining diffusion multiple and BP neural network, a Ti alloy (Ti–3Al–2Nb-1.2V–1Zr–1Sn–4Cr–4Mo) with outstanding mechanical properties was successfully designed. The mechanical test result shows that excellent balance of strength (YS~1200 MPa) and plasticity (El~12%) can be achieved after the solution treatment at 750 °C and aging at 550 °C for 6 h. During deformation, Primary globular primary α phases were elongated, and secondary acicular α phases resisted the dislocation slipping, which provides good plasticity and strength for the alloys, respectively.

In December 2019, an outbreak of the novel coronavirus pneumonia infection occurred in Wuhan City, Hubei Province, China, and it has received substantial attention globally. Few studies have investigated the psychological stress of students in Health University during the COVID-19 outbreak, and almost no work has attended to the influencing factors that may cause their psychological stress risk. This cross-sectional, survey-based, region-stratified study collected demographic data and mental measurement from 2,498 medical students and 1,177 non-medical students in 31 provinces from March 5, 2020, to March 10, 2020, in China. The psychological stress was measured using the Chinese Perceived Stress Scales (CPSS) under a self-design questionnaire. Sociodemographic, major characteristics, and knowledge of the novel coronavirus pneumonia were also identified as potential influencing factors of stress. The study revealed that medical students are suffering from more stress than non-medical students almost in all provinces of China. Four influencing factors including level of familiarity with the novel coronavirus, family income, major of students, and status of the intern student can be significantly related to students’ stress in the medical group by using the univariate and multivariate analysis. Further analysis showed that students with low stress had a greater number of positive psychological emotions and a lower number of negative psychological emotions than with medical students with high stress. In addition, high stress caused low enthusiasm for learning in these medical students and lead to little/no willingness to do professional medical work in the future. In conclusion, we need to increase the level of our knowledge related to the novel coronavirus pneumonia to reduce stress and strongly focus on the special populations in medical students with certain features, such as intern students, clinical nursing students, and low-income families, to improve their learning attitudes and establish positive professional mental outlooks.

Endosseous titanium (Ti) implant failure due to poor biocompatibility of implant surface remains a major problem for osseointegration. Improving the topography of Ti surface may enhance osseointegration, however, the mechanism remains unknown. To investigate the effect of modified Ti surface on osteogenesis, we loaded rapamycin (RA) onto nano-hydroxyapatite (HAp) coated Ti surface which was acid-etched, alkali-heated and HAp coated sequentially. Sodium hyaluronate (SH) was employed as an intermediate layer for the load of RA, and a steady release rate of RA was maintained. Cell vitality of MC3T3-E1 was assessed by MTT. Osteogenesis of MC3T3-E1 on this modified Ti surface was evaluated by alkaline phosphatase (ALP) activity, mineralization and related osteogenesis genes osteocalcin (OCN), osteopontin (OPN), Collagen-I and Runx2. The result revealed that RA/SH-loaded nano-HAp Ti surface was innocent for cell vitality and even more beneficial for cell osteogenesis in vitro. Furthermore, osteogenesis of MC3T3-E1 showed significant association with the mammalian target of rapamycin (mTOR) phosphorylation by RA, which required further study about the mechanism. The approach to this modified Ti surface presented in this paper has high research value for the development of Ti-based implant.

Modulating inflammation is crucial for repairing vascular injury. Phagocytosis of apoptotic cells represents an effective mechanism for attenuating inflammation and improving regeneration during natural healing. However, strategies for repairing vascular injuries using biomaterials derived from apoptotic cells are still undeveloped. Herein, apoptotic body‐mimetic nanovesicles (ApoNVs) derived from rat adipose‐derived mesenchymal stem cells (rASCs) are prepared using a one‐step extrusion method. ApoNVs inherit the unique anti‐inflammatory and pro‐regenerative properties of the parental apoptotic rASCs, as evidenced by enhanced M2 polarization of macrophages and promoted endothelial cell proliferation and migration following treatment with ApoNVs. Moreover, ApoNVs enhance the contractile phenotype of vascular smooth muscle cells through the mediation of ApoNVs‐induced repolarized macrophages. After engineering ApoNVs with P‐selectin binding peptide (ApoNVs‐PBP), their ability to target injured artery increased nearly sevenfold compared to unmodified ApoNVs. In a rat wire‐mediated femoral artery injury model, ApoNVs‐PBP effectively suppress inflammation and significantly reduce blood flow velocity and neointimal hyperplasia at the injury site. ApoNVs exhibit similar therapeutic effects, though to a lesser extent. This study provides strong evidence validating the targeted delivery of ApoNVs as an innovative approach for repairing vascular injury and highlights their potential in treating other inflammatory diseases. [ABSTRACT FROM AUTHOR]

The flow distribution pair of the piston pump, the largest contact area among the three friction pairs in a plunger pump, significantly influences the pump's overall performance. Magnetic fluid sealing, a novel sealing method, offers advantages such as zero leakage, long lifespan, high reliability, and no pollution, making it widely applicable across various fields. This approach provides a new solution for the end-face sealing valve plate pairs in plunger pumps. To address the leakage issue of the flow distribution pair, we designed a magnetic fluid radial sealing structure for the end face of the flow distribution pair and optimized the key parameters of the sealing structure by numerical simulation. Based on the optimization results, we developed a corresponding magnetic fluid sealing device and tested its pressure resistance performance under both static and dynamic conditions. The experimental results indicate that the sealing performance is superior when sealing gases compared to liquids, especially under dynamic conditions. This is attributed to the instability of the sealing interface caused by centrifugal force, leading to seal failure. Under static conditions, the sealing performance primarily depends on the saturation magnetization of the magnetic fluid and is independent of other physical properties. In dynamic conditions, the pressure resistance decreases with increasing speed. While the viscosity of the magnetic fluid impacts the sealing performance, the saturation magnetization remains the critical factor determining the critical sealing capacity. These findings provide valuable insights for the design of end-face radial magnetic fluid sealing devices. [ABSTRACT FROM AUTHOR]

Vascular injury is central to the pathogenesis and progression of cardiovascular diseases, however, fostering alternative strategies to alleviate vascular injury remains a persisting challenge. Given the central role of cell‐derived nitric oxide (NO) in modulating the endogenous repair of vascular injury, NO‐generating proteolipid nanovesicles (PLV‐NO) are designed that recapitulate the cell‐mimicking functions for vascular repair and replacement. Specifically, the proteolipid nanovesicles (PLV) are versatilely fabricated using membrane proteins derived from different types of cells, followed by the incorporation of NO‐generating nanozymes capable of catalyzing endogenous donors to produce NO. Taking two vascular injury models, two types of PLV‐NO are tailored to meet the individual requirements of targeted diseases using platelet membrane proteins and endothelial membrane proteins, respectively. The platelet‐based PLV‐NO (pPLV‐NO) demonstrates its efficacy in targeted repair of a vascular endothelium injury model through systemic delivery. On the other hand, the endothelial cell (EC)‐based PLV‐NO (ePLV‐NO) exhibits suppression of thrombosis when modified onto a locally transplanted small‐diameter vascular graft (SDVG). The versatile design of PLV‐NO may enable a promising therapeutic option for various vascular injury‐evoked cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Baking is the most costly and critical process in anode preparation, and the study from the microscopic scale is conducive to the optimisation of anode baking process. In this research, a hybrid simulation method of reactive force field molecular dynamics (ReaxFF-MD) and force-biased Monte Carlo (fbMC) was proposed to understand the interaction mechanism between coal tar pitch (CTP) and calcined petroleum coke (CPC) during kneading and baking processes, and to explore the optimal ratio of CTP from the molecular scale. Results showed that the CTP content of 14 wt.% was beneficial for anode production. The mechanism of anode coking behaviour at high temperatures was also analyzed. The carbonisation of CTP during high-temperature baking broke the carbon rings and formed straight chains, exposing active carbon atoms that can bond with the remaining layers. As the high-temperature simulation progresses, the carbon chains at the bonding sites became increasingly cyclized and aromatised, which made the layered structure of the baked block similar to that of graphite. The generation of various volatile hydrocarbons during the baking process was observed, namely CH4, C2H4, C2H2, C2H6, and C3H6. This work provides theoretical basis for process optimisation. [ABSTRACT FROM AUTHOR]