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This study explored the three-dimensional flow characteristics in a recirculation zone near a permeable buttress in curved channels with varying curvatures. Understanding these characteristics is crucial for managing natural river bends, as rivers often meander, with backwater zones formed behind obstructions, such as mountains in the riverbed. The direct comparison of the recirculation zones across different bend types revealed the correlation between the flow characteristics and bend curvature. However, previous studies have focused on flow velocities and turbulent kinetic energy without a probability density analysis. This analysis provided a more comprehensive understanding of the flow characteristics. Gaussian kernel density estimation was applied in this study to observe the distribution of the flow velocities, turbulent kinetic energy, and turbulent kinetic energy dissipation rate. The results indicated that the longitudinal time-averaged flow velocity in the recirculation zone typically ranged from −0.2 m/s to −0.8 m/s, with all the skewness coefficients exceeding 0. The horizontal time-averaged flow velocity in the recirculation zone fell between −0.175 m/s and −0.1 m/s. The skewness coefficients were negative at water depths of 16%, 33%, and 50% within the 90° and 180° bends, indicating a non-normal distribution. The probability density distribution of turbulent kinetic energy in the recirculation zone was skewed, ranging from 0 to 0.02 m2·s−2, with the skewness coefficient almost always greater than 0. The plot demonstrated multiple peaks, indicating a broad distribution of turbulent kinetic energy rather than a concentration within a specific interval. This distribution included both the high and low regions of turbulent kinetic energy. Although the overall rate of turbulent kinetic energy dissipation in the recirculation zone was relatively low, there were multiple peaks, suggesting the localized areas with higher dissipation rates alongside the regions with lower rates. These findings were significant for managing the meandering river channels, restoring the subaqueous ecosystems, understanding the pollutant diffusion mechanisms in backwater areas, the sedimentation of nutrient-laden sediments, and optimizing the parameters for spur dike design. [ABSTRACT FROM AUTHOR]

In this paper, a numerical computation method for the Gierer–Meinhardt model in two-dimensional space diffusion with homogeneous Neumann boundary conditions, considering the interaction between activator and inhibitor substances, is proposed. First, a high-order compact finite difference scheme is constructed for the Gierer–Meinhardt model using the finite difference method. A fourth-order compact difference scheme is applied to the second-order spatial derivative terms, while the time derivative terms are discretized using Taylor series expansion and residual correction functions. Consequently, the difference scheme achieves fourth-order accuracy in space and second-order accuracy in time for the Gierer–Meinhardt model. In addition, the stability of the difference scheme is demonstrated using Fourier analysis. Finally, numerical simulations are conducted on the Gierer–Meinhardt model near its equilibrium point to explore the impact of the inhibitor degradation rate, denoted as E, on the pattern formation. The model exhibits distinct pattern structures with varying E, thereby revealing the relationship between tissue variability and pattern formation in biological systems. [ABSTRACT FROM AUTHOR]

Transcription factor EB (TFEB)-based gene therapy is a promising therapeutic strategy in treating neurodegenerative diseases by promoting autophagy/lysosome-mediated degradation and clearance of misfolded proteins that contribute to the pathogenesis of these diseases. However, recent findings have shown that TFEB has proinflammatory properties, raising the safety concerns about its clinical application. To investigate whether TFEB induces significant inflammatory responses in the brain, male C57BL/6 mice were injected with phosphate-buffered saline (PBS), adeno-associated virus serotype 8 (AAV8) vectors overexpressing mouse TFEB (pAAV8-CMV-mTFEB), or AAV8 vectors expressing green fluorescent proteins (GFPs) in the barrel cortex. The brain tissue samples were collected at 2 months after injection. Western blotting and immunofluorescence staining showed that mTFEB protein levels were significantly increased in the brain tissue samples of mice injected with mTFEB-overexpressing vectors compared with those injected with PBS or GFP-overexpressing vectors. pAAV8-CMV-mTFEB injection resulted in significant elevations in the mRNA and protein levels of lysosomal biogenesis indicators in the brain tissue samples. No significant changes were observed in the expressions of GFAP, Iba1, and proinflammation mediators in the pAAV8-CMV-mTFEB-injected brain compared with those in the control groups. Collectively, our results suggest that AAV8 successfully mediates mTFEB overexpression in the mouse brain without inducing apparent local inflammation, supporting the safety of TFEB-based gene therapy in treating neurodegenerative diseases.

The COVID-19 pandemic is a major public health emergency and a significant stressor to most people. The objective of this study was to examine the mental health status and social support level of participants from 2019 to 2020. The study aimed to investigate the changes in people's psychological capital state due to the COVID-19 pandemic. A longitudinal study was performed to study the psychosocial predictors of mental health among a sample of 2,999 Chinese employees in 2019, and the follow-up survey was conducted one year later. Regression coefficients were visualized in a heatmap. Path analysis was performed base on the structural equation model (SEM) to measure the associations between study variables. The status of mental health, resilience, and optimism changed significantly during the pandemic (P < 0.05). The level of employee's social support in 2019 could significantly and positively predicted the level of employee's psychological capital in 2020, and the level of employee mental health in 2019 significantly and negatively predicted the level of employee psychological capital in 2020. The mental health of employees played an intermediary role between social support and psychological capital. These results highlight that the COVID-19 pandemic has a strong impact on the psychological capital of company employees. While demanding performance, corporations should ensure timely intervention in the mental health of their employees. [ABSTRACT FROM AUTHOR]

Leukoaraiosis (LA) is a disease manifested by demyelination and gliosis in white matter, mainly caused by cerebrovascular diseases. LA is closely related to the expression level of inflammatory factors, oxidative stress, and vascular endothelial dysfunction in patients. Vitamin E may play antioxidant and anti-inflammatory roles in various diseases. We aimed to explore the effects of vitamin E on the patients with LA. A total of 160 patients with LA were recruited in this research. Matrix metalloproteinase-9 (MMP-9), MMP-2, C-reactive protein (CRP), complement 3 (C3), C4, nitric oxide (NO), and endothelin (ET) levels were evaluated by ELISA. The Mini-Mental State Examination (MMSE) was used for cognitive impairment assessment. Superoxide dismutase (SOD) and malondialdehyde (MDA) concentrations were analyzed by commercial kits. The levels of CRP, C3, and C4 significantly decreased in the serum of LA patients after the administration of vitamin E. The levels of MMP-2 and MPP-9 showed a significant decrease in the administered group. Vitamin E significantly inhibited the expression of MDA, while significantly upregulated the expression of SOD. Significant increase in NO production and significant downregulation of ET expression occurred in vitamin E groups. MMSE score was significantly increased by vitamin E. In conclusion, vitamin E showed effects on the alleviation of inflammatory response, oxidative stress, endothelial damage, and cognitive dysfunction. Thus, vitamin E could be a potential drug for the clinical treatment of LA patients. [ABSTRACT FROM AUTHOR]

Previous studies have reported high rates of poor mental health among nursing students, but few studies focused on the internal pathway of mental health. This cross-sectional study was conducted at a vocational medical school and investigated 384 nursing students. Symptom Check List-90, Index of Well-Being Scale and Cynical Attitudes Toward College Scale were used to test mental health, subjective well-being (SWB) and cynicism of nursing students, respectively. Academic cynicism, social cynicism and institutional cynicism were negatively related to mental health. SWB not only directly had positive effect on mental health, but had an indirect effect on mental health through academic cynicism, social cynicism and institutional cynicism. [ABSTRACT FROM AUTHOR]

This study explores the association between life satisfaction and depression among patients with cardiovascular diseases and whether this association is mediated by self-esteem. A cross-sectional study was conducted in a third-grade hospital. We examined 300 patients with cardiovascular diseases with a mean age of 62.00 years (females, 133). Life satisfaction was associated with depression. Adding self-esteem to the model weakened the strength of the association between the two. Moreover, 34.2% of the effect of life satisfaction on depression could be explained by self-esteem. We found that self-esteem could totally explain the effect of life satisfaction on depression among patients with cardiovascular diseases. [ABSTRACT FROM AUTHOR]