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Polyimide (PI) is an indispensable material in the field of electrical insulation devices owing to its high mechanical strength, high insulating properties and excellent thermal stability. However, the rigid structure not only gives PI these excellent properties but also makes it difficult for PI to self-heal, be recycled, and reused. Herein, a self-healable PI (SHPI) film is developed by the synergistic combination of dynamic disulfide bonds and flexible polysiloxane molecules (PDMS). Two functional monomers are introduced into the PI matrix through simple copolymerization, which confers excellent self-healing and recycling abilities. Furthermore, the SHPI retains high thermal stability with thermal decomposition temperature at 5 wt% weight reduction (Td5%) = 427 °C and good breakdown strength (E0 ∼ 318 MV m−1). Moreover, carbon fiber (CF) reinforced composite films (CFRCs) by combining SHPI with CFs are also produced, and they exhibit excellent mechanical strength and load-bearing capacity. The CFs can be reused multiple times with a recycling efficiency of nearly 100%. The SHPI is expected to have widespread use and popularity in the field of electrical insulation as an excellent recyclable insulation material. [ABSTRACT FROM AUTHOR]

The COVID-19 outbreak led to widespread school closures and the shift to remote teaching, potentially resulting in lasting negative impacts on teachers' psychological well-being due to increased workloads and a perceived lack of administrative support. Despite the significance of these challenges, few studies have delved into the long-term effects of perceived instructional leadership on teachers' psychological health. To bridge this research gap, we utilized longitudinal data from 927 primary and secondary school teachers surveyed in two phases: Time 1 in mid-November 2021 and Time 2 in early January 2022. Using hierarchical linear modeling (HLM), our findings revealed that perceptions of instructional leadership, especially the "perceived school neglect of teaching autonomy" at Time 1 were positively correlated with burnout levels at Time 2. Additionally, burnout at Time 2 was positively associated with psychological distress and acted as a mediator between the "perceived school neglect of teaching autonomy" and psychological distress. In light of these findings, we recommend that schools prioritize teachers' teaching autonomy and take proactive measures to mitigate burnout and psychological distress, aiming for the sustainable well-being of both teachers and students in the post-pandemic era. [ABSTRACT FROM AUTHOR]

In the modelling of hydrological processes on a regional scale, remote-sensing snow depth products with a high spatial and temporal resolution are essential for climate change studies and for scientific decision-making by management. The existing snow depth products have low spatial resolution and are mostly applicable to large-scale studies; however, they are insufficiently accurate for the estimation of snow depth on a regional scale, especially in shallow snow areas and mountainous regions. In this study, we coupled SSM/I, SSMIS, and AMSR2 passive microwave brightness temperature data and MODIS, TM, and Landsat 8 OLI fractional snow cover area (fSCA) data, based on Python, with 30 m spatially resolved fractional snow cover area (fSCA) data obtained by the spatio-temporal dynamic warping algorithm to invert the low-resolution passive microwave snow depths, and we developed a spatially downscaled snow depth inversion method suitable for the Turpan–Hami region. However, due to the long data-processing time and the insufficient arithmetical power of the hardware, this study had to set the spatial resolution of the result output to 250 m. As a result, a day-by-day 250 m spatial resolution snow depth dataset for 20 hydrological years (1 August 2000–31 July 2020) was generated, and the accuracy was evaluated using the measured snow depth data from the meteorological stations, with the results of r = 0.836 (p ≤ 0.01), MAE = 1.496 cm, and RMSE = 2.597 cm, which are relatively reliable and more applicable to the Turpan–Hami area. Based on the spatially downscaled snow depth data produced, this study found that the snow in the Turpan–Hami area is mainly distributed in the northern part of Turpan (Bogda Mountain), the northwestern part of Hami (Barkun Autonomous Prefecture), and the central part of the area (North Tianshan Mountain, Barkun Mountain, and Harlik Mountain). The average annual snow depth in the Turpan–Hami area is only 0.89 cm, and the average annual snow depth increases with elevation, in line with the obvious law of vertical progression. The annual mean snow depth in the Turpan–Hami area showed a "fluctuating decreasing" trend with a rate of 0.01 cm·a−1 over the 20 hydrological years in the Turpan–Hami area. Overall, the spatially downscaled snow depth inversion algorithm developed in this study not only solves the problem of coarse spatial resolution of microwave brightness temperature data and the difficulty of obtaining accurate shallow snow depth but also solves the problem of estimating the shallow snow depth on a regional scale, which is of great significance for gaining a further understanding of the snow accumulation information in the Tuha region and for promoting the investigation and management of water resources in arid zones. [ABSTRACT FROM AUTHOR]

The physiological changes in cut flowers after harvest accelerates their senescence process and greatly affects the quality of cut flowers. Thus the preservation technology is a key factor in limiting the development of the cut-flower industry. The objective of the present study was to explore a new method of preserving cut roses to reduce post-harvest storage and transportation losses. Cut roses were packaged in polyethylene (PE) bags of 40 × 110 cm, with 0, 2, 6, 20, and 30 microperforations of 600 μm at 4°C. The adjustment of the number of microperforations allowed the control of gas concentrations inside the packaging, and those with 20 microperforations permitted the best quality characteristics at 4°C. The findings revealed variations in the gas environment within modified atmosphere packaging (MAP) with different numbers of micropores, which exerted diverse effects on the preservation of cut rose flowers. The MAP with 20 micropores demonstrated the most effective preservation outcome. It not only effectively maintains the antioxidant capacity, the vitality of POD, SOD, and anti-superoxide anion in cut roses but also inhibits the accumulation of H2O2 content. Additionally, it effectively maintained the storage quality by inhibiting the respiration rate, ethylene production rate, and decay rate in cut roses. [ABSTRACT FROM AUTHOR]

Purpose: To systematically review the available evidence regarding the prevalence and outcomes of cognitive frailty—a clinical syndrome characterized by the combination of physical frailty and cognitive impairment, without dementia—in community-dwelling older adults. Method: The following databases were searched: PubMed, Web of Science, Embase, EBSCO, Cochrane Central Register of Controlled Trials, ProQuest, CNKI, Wanfang, VIP, and CBMdisc (inception to October 2, 2023). Results: Twenty-four studies were included (N = 62,169) reporting a median prevalence of cognitive frailty among community-dwelling older adults of 12.2%. Frailty with cognitive impairment was independently associated with increased all-cause mortality (adjusted 8-year hazard ratio [HR] = 2.6, 95% confidence interval [CI] [2.05, 3.30]). There was evidence of increased risk of 3-year mortality for frailty (adjusted HR = 1.92, 95% CI [1.26, 2.93]) and prefrailty (adjusted HR = 1.79, 95% CI [1.33, 2.41]) with cognitive impairment. There was also evidence of increased risk of dementia for frailty (adjusted 24-month HR = 6.19, 95% CI [2.74, 13.99]; adjusted 4-year HR = 4.98, 95% CI [2.17, 11.41]) and prefrailty (adjusted 4-year HR = 5.21, 95% CI [2.95, 9.20]; adjusted 5-year HR = 14.5, 95% CI [1.68, 125.1]) with cognitive impairment. Activities of daily living (ADL) dependence was more frequent in individuals with cognitive impairment and frailty (adjusted 4-year odds ratio = 5.6, 95% CI [2.13, 14.72]). Conclusion: Of community-dwelling older adults, 12.2% have cognitive frailty as well as increased risk of all-cause mortality, dementia, and ADL dependence. Further studies on prevention and treatment of cognitive frailty is warranted. Health care providers should formulate specific interventions to decrease the impact of cognitive frailty. [Research in Gerontological Nursing, 17(4), 202–212.] [ABSTRACT FROM AUTHOR]

Chronic inflammation and excessive reactive oxygen species (ROS) can impair diabetic wound healing. Regulatory T cells (Tregs) have emerged as a promising target to promote wound healing by regulating the immune system and supporting tissue repair through the secretion of growth factors and cytokines. However, an effective strategy for the on‐demand recruitment of Tregs for wound healing is still lacking. Here, an ROS‐scavenging Tregs‐recruiting hydrogel patch is developed for the sequential release of C─C motif chemokine 22 (CCL22) triggered by the ROS in the diabetic wound bed. The hydrogel patch is prepared by crosslinking the gelatin with ROS cleavable linker together with CCL22 (RSG‐CCL22). RSG‐CCL22 presented desirable physical properties suitable for skin regeneration purposes. In addition, the ROS scavenging feature of the RSG suppresses the differentiation of T helper 17 (Th17) cells and protects the recruited Tregs from apoptosis and oxidative stress, which maximizes their function in accelerating wound closure and promoting hair follicle regeneration in a diabetic full‐thickness skin defect mouse model. Therefore, the proposed approach provides a new therapeutic strategy for tissue regeneration and wound repair via effective recruitment of functional Tregs through ROS‐triggered on‐demand delivery. [ABSTRACT FROM AUTHOR]

HOTAIRM1, a newly found long non-coding RNA (lncRNA), is abnormally expressed in diverse malignant tumors, regulated mRNA, miRNA, relevant target gene or protein through specific signal transduction pathways to function in mechanisms of proliferation, invasion and metastasis of tumor cells. HOTAIRM1 is closely related to the clinicopathology or molecular pathology and have shown great potential in therapy and predicting prognosis of patients.

Low packing densities are key structural features of amphidynamic crystals built with static and mobile components. Here we report a loosely packed crystal of dendrimeric rotor 2 and the fast dynamics of all its aromatic groups, both resulting from the hyperbranched structure of the molecule. Compound 2 was synthesized with a convergent strategy to construct a central phenylene core with stators consisting of two layers of triarylmethyl groups. Single crystal X-ray diffraction analysis confirmed a low-density packing structure consisting of one molecule of 2 and approximately eight solvent molecules per unit cell. Three isotopologues of 2 were synthesized to study the motion of each segment of the molecule in the solid state using variable temperature quadrupolar echo (2)H NMR spectroscopy. Line shape analysis of the spectra reveals that the central phenylene, the six branch phenylenes, and the 18 periphery phenyls all display megahertz rotational dynamics in the crystals at ambient temperature. Arrhenius analysis of the data gives similar activation energies and pre-exponential factors for different parts of the structure. The observed pre-exponential factors are 4-6 orders of magnitude greater than those of elementary site-exchange processes, indicating that the dynamics are not dictated by static energetic potentials. Instead, the activation energies for rotations in the crystals of 2 are controlled by temperature dependent local structural fluctuations and crystal fluidity.

Tyrosinase (EC 1.14.18.1) catalyzes both the hydroxylation of tyrosine into o-diphenols and the oxidation of o-diphenols into o-quinones that form brown or black pigments. In the present paper, cefotaxime, a cephalosporin antibacterial drug, was tested as an inhibitor of tyrosinase. The results show that cefotaxime inhibits both the monophenolase and diphenolase activities of tyrosinase. For the monophenolase activity, cefotaxime increased the lag time and decreased the steady-state activity with an IC50 of 3.2 mM. For the diphenolase activity, the inhibition by cefotaxime is reversible and mix-I type with an IC50 of 0.14 mM. The inhibition constants (K(I) and K(IS)) were determined to be 0.14 and 0.36 mM, respectively. The molecular mechanism of inhibition of tyrosinase by cefotaxime was determined by fluorescence quenching and molecular docking. The results demonstrated that cefotaxime was a static quencher of tyrosinase and that cefotaxime could dock favorably in the active site of tyrosinase. This research may offer a lead for designing and synthesizing novel and effective tyrosinase inhibitors in the future.

To identify false-positive SARS-CoV-2 test results caused by novel coronavirus inactivated vaccine contamination, a novel RT-qPCR targeting the ORF1ab and N genes of SARS-CoV-2 and Vero gene was developed. The amplification efficiency, precision, and lower limit of detection (LLOD) of the RT-qPCR assay were determined. A total of 346 clinical samples and 132 environmental samples were assessed, and the diagnostic performance was evaluated. The results showed that the amplification efficiency of the ORF1ab, N, and Vero genes was 95%, 97%, and 93%, respectively. The coefficients of variation of Ct values at a concentration of 3 × 104 copies/mL were lower than 5%. The LLOD for the ORF1ab, N, and Vero genes reached 8.0, 3.3, and 8.2 copies/reaction, respectively. For the 346 clinical samples, our RT-qPCR assay identified SARS-CoV-2-positive and SARS-CoV-2-negative samples with a sensitivity of 100.00% and a specificity of 99.30% and novel coronavirus inactivated vaccine-contaminated samples with a sensitivity of 100% and a specificity of 100%. For the environmental samples, our RT-qPCR assay identified novel coronavirus inactivated vaccine-contaminated samples with a sensitivity of 88.06% and a specificity of 95.38%. In conclusion, the RT-qPCR assay we established can be used to diagnose COVID-19 and, to a certain extent, false-positive results due to vaccine contamination.

Underwater visual detection technology is crucial for marine exploration and monitoring. Given the growing demand for accurate underwater target recognition, this study introduces an innovative architecture, YOLOv8-MU, which significantly enhances the detection accuracy. This model incorporates the large kernel block (LarK block) from UniRepLKNet to optimize the backbone network, achieving a broader receptive field without increasing the model's depth. Additionally, the integration of C2fSTR, which combines the Swin transformer with the C2f module, and the SPPFCSPC_EMA module, which blends Cross-Stage Partial Fast Spatial Pyramid Pooling (SPPFCSPC) with attention mechanisms, notably improves the detection accuracy and robustness for various biological targets. A fusion block from DAMO-YOLO further enhances the multi-scale feature extraction capabilities in the model's neck. Moreover, the adoption of the MPDIoU loss function, designed around the vertex distance, effectively addresses the challenges of localization accuracy and boundary clarity in underwater organism detection. The experimental results on the URPC2019 dataset indicate that YOLOv8-MU achieves an mAP@0.5 of 78.4%, showing an improvement of 4.0% over the original YOLOv8 model. Additionally, on the URPC2020 dataset, it achieves 80.9%, and, on the Aquarium dataset, it reaches 75.5%, surpassing other models, including YOLOv5 and YOLOv8n, thus confirming the wide applicability and generalization capabilities of our proposed improved model architecture. Furthermore, an evaluation on the improved URPC2019 dataset demonstrates leading performance (SOTA), with an mAP@0.5 of 88.1%, further verifying its superiority on this dataset. These results highlight the model's broad applicability and generalization capabilities across various underwater datasets. [ABSTRACT FROM AUTHOR]

Previous studies have revealed that Propane-2-sulfonic acid octadec-9-enyl-amide(N15) exerts a protective role in the inflammatory response after ischemic stroke and in neuronal damage. However, little is known about N15 in Alzheimer's disease (AD). The aim of this study was to investigate the effects of N15 on AD and explore the underlying molecular mechanism. AD mice model was established by lateral ventricular injection with Aβ25–35. N15 was daily intraperitoneal administered for 28 days. Morris Water Maze was used to evaluate the neurocognitive function of the mice. The expression of PPARα/γ, brain-derived neurotrophic factor (BDNF), Neurotrophin-3 (NT3), ADAM10, PS1 and BACE1 were measured by qPCR. Aβ amyloid in the hippocampus was measured by Congo red assay. Toluidine blue staining was used to detect the neuronal apoptosis. Protein levels of ADAM10, PS1 and BACE1 were determined using immunoblotting. N15 treatment significantly reduced neurocognitive dysfunction, which also significantly activated the expression of PPARα/γ at an optimal dose of 200 mg/kg. Administration of N15 alleviated the formation of Aβ amyloid in the hippocampus of AD mice, enhanced the BDNF mRNA expression, decreased the mRNA and protein levels of PS1 and BACE1, upregulated ADAM10 mRNA and protein levels. N15 exerts its neuroprotective effects through the activation of PPARα/γ and may be a potential drug for the treatment of AD. [ABSTRACT FROM AUTHOR]

The southwest vortices (SWVs) are a unique type of mesoscale vortex that frequently induce torrential rainfall in China. In this study, we focused a long‐lived quasi‐stationary SWV, which was the primary system for producing an extremely heavy rainstorm within/around Sichuan (the maximum hourly precipitation was ~103.8 mm) in Mid July 2021. After reproduced the SWV's formation by using Weather Research and Forecasting model, we conducted trajectory analyses and topography sensitivity simulations to understand the effects of complicated topography on the vortex's formation. It is found that, the regions south and southwest of the SWV acted as the most important source regions for the air clusters that formed the SWV (proportion ≥ 65%), and the air clusters originated from the upper layer contributed the most (≥60%). Of these, the air clusters sourced from the upper layer southwest and south of the SWV played the most important role in the SWV's formation, as their increase in cyclonic vorticity and their contributions to trajectory number and vorticity were all much larger than those of the others. Sensitivity simulations indicated that, detailed topography features around the Sichuan Basin were crucial in determining the structure, intensity and precipitation of the SWV, whereas, the topography features were not a decisive factor for the SWV's formation. In summary, our findings are useful to enrich the current understanding of the SWVs' formation, which would be helpful to improve the related forecasts. [ABSTRACT FROM AUTHOR]

Several modifiable lifestyle risk factors have been linked to higher cancer risk in the literature. Determining the proportion and number of cancer cases attributable to these risk factors is pivotal in informing effective cancer prevention and control plans that have the greatest effect on reducing cancer incidence. We aimed to estimate the proportion and number of incident cancer cases that were attributable to modifiable lifestyle risk factors (ie, tobacco smoking, high alcohol consumption, excess body weight, physical inactivity and unhealthy diet) in Switzerland between 2015 and 2019. The exposure prevalence of selected risk factors was estimated based on the representative national nutrition survey menuCH, the associated relative risks were obtained from systematic literature reviews and the numbers of incident cancer cases were provided by the National Institute for Cancer Epidemiology and Registration. The fractions and numbers of attributable cases were calculated overall, by sex and by the three major language regions of Switzerland. The investigated modifiable risk factors combined were linked to 25.2% of potentially preventable incident cancer cases in Switzerland between 2015 and 2019. The proportion and numbers were slightly larger in males (28.4%, 6945 cases per year) than in females (21.9%, 4493 cases per year), and variations were observed between language regions. Tobacco smoking, excess body weight and high alcohol consumption were the leading contributors to lifestyle‐attributable cancer cases. The observed differences in the leading risk factors both within Switzerland and compared to other countries underline the need for regionally and nationally tailored cancer prevention and education strategies. [ABSTRACT FROM AUTHOR]