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In order to better solve the fuzziness and uncertainty in the evaluation index of mine emergency rescue team’s ability, the cloud model method is used to evaluate the ability of mine emergency rescue team, and the evaluation system is constructed by combining the first and second indexes, such as support system, institutional basis, comprehensive constitution, organizational construction and professional rescue. With the cloud theory, the index weight cloud and standard cloud are set up. The final evaluation cloud of each indicator is obtained based on the information of each evaluation indicator and cloud computing rules. Finally, compared with the evaluation standard cloud, the advantages and disadvantages are determined. The capacity evaluation standard of mine emergency rescue team can comprehensively and scientifically evaluate the capacity of mine emergency rescue team. The cloud model was used to find that Kailuan emergency rescue team had good command and management ability and comprehensive physical ability, but there were certain deficiencies in professional rescue, organizational construction and support system. The method is scientific, and the result is more intuitive with the help of evaluation cloud map, which is helpful to improve the level of mine accident emergency rescue.

In order to promote the cardiopulmonary function and health of miners in plateau areas, this paper uses scientific methods such as questionnaire survey, mathematical statistics and comparative analysis to test the cardiopulmonary function of healthy adult miners in Chian Tyrone, Tibet (high altitude area) and Kailuan, Hebei(low altitude area), and studies the test results from three dimensions of ventilation index, metabolic index and heart rate variability index.The results showed that there were significant differences in ventilation index, metabolism index and heart rate variability index between the plateau miners and the plain miners, and the indexes showed that the cardiopulmonary function of the plateau miners was significantly weaker than that of the plain miners.Based on the above research results, some suggestions were put forward to improve the cardiopulmonary function of plateau miners.This research has certain reference value and significance for improving the health of miners working on plateaus.

BACKGROUND: Physical activity (PA) holds profound implications for the holistic development of college students. However, students with chronic diseases or physical disabilities experience significantly limited PA during adaptive sports. OBJECTIVE: This study aims to investigate the relationship between physical activity and Functional Movement Screening (FMS) among university students who participate in the adaptive physical course. METHODS: 36 university students (from the adaptive physical course) completed the International Physical Activity Questionnaire-Long Form (IPAQ-L). Body measurements and FMS were assessed. Correlation analysis and t -tests were used to determine relationships and differences between various indicators. A two-way analysis of variance was used to investigate potential variations in FMS scores based on gender and weight status. RESULTS: The results show that gender, PA, and BMI significantly influence FMS scores in students participating in adaptive physical courses. FMS score is significantly negatively correlated with BMI and significantly positively correlated with PA. The FMS score for males, as well as the scores for Trunk Stability Push-Up and Rotary Stability, are significantly higher than those for females. CONCLUSION: University students in adaptive physical courses can benefit from increased PA and FMS scores. Improving functional movement and enhancing physical activity are crucial for promoting overall health in this population. [ABSTRACT FROM AUTHOR]

Broadband photodetectors with polarization-sensitive ability have received extraordinary attention for modern optoelectronic devices. Ideal photodetectors should possess high responsivity, fast response, and good stability, which are rare to meet at the same time in one low-symmetric two-dimentional (2D) material. In this work, neodymium diantimonides (NdSb2), a member of light rare-earth diantimonides RSb2 (R = La−Nd, Sm) with low-symmetry structure, is introduced as a fascinating highly anisotropic 2D material for broadband detection (532 nm to 4 µm). The photodetector exhibits a responsivity of 0.49 mA·W−1 with 15 µs response time at 532 nm and highly stable performance under ambient conditions over 8 months. Furthermore, we identify the polarization-sensitive photoresponse of the detector and demonstrate a high anisotropic factor ∼ 1.6. In addition, strong in-plane anisotropy is revealed by anisotropic phonon response and the photodetection mechanism is investigated by scanning photocurrent microscopy measurements. This pioneer work on NdSb2 paves the way for further exploration of 2D RSb2 for high performance polarized photodetectors with fast photothermoelectric response. [ABSTRACT FROM AUTHOR]

Corner-truncated octahedral Cu2O microcrystal was synthesized by a typical solution phase reduction method with CuSO4, glucose, and a small amount of NaOH. Researching into the reaction process, we found that the Cu2O microcrystal grew following the sol–gel growth model, instead of Lamer nucleation–diffusion model. The roles that OH− and SO42− played in the formation of the octahedral morphology were revealed by separating them and investigating the corresponding products, respectively. We used PVP (polyvinylpyrrolidone) in another experiment to show that the influence of the organic surfactant on the crystal habit may also be demonstrated more clearly using this method. [ABSTRACT FROM AUTHOR]

P‐n junctions based on two dimensional (2D) van der Waals (vdW) heterostructure are one of the most promising alternatives in next‐generation electronics and optoelectronics. By choosing different 2D transition metal dichalcogenides (TMDCs), the p‐n junctions have tailored energy band alignments and exhibit superior performance as photodetectors. The p‐n diodes working at reverse bias commonly have high detectivity due to suppressed dark current but suffer from low responsivity resulting from small quantum efficiency. Greater build‐in electric field in the depletion layer can improve the quantum efficiency by reducing recombination of charge carriers. Herein, Cu9S5, a novel p‐type semiconductor with direct bandgap and high optical absorption coefficient, is synthesized by salt‐assisted chemical vapor deposition (CVD) method. The high density of holes in Cu9S5 endows the constructed p‐n junction, Cu9S5/MoS2, with strong build‐in electric field according to Anderson heterojunction model. Consequently, the Cu9S5/MoS2 p‐n heterojunction has low dark current at reverse bias and high photoresponse under illumination due to the efficient charge separation. The Cu9S5/MoS2 photodetector exhibits good photodetectivity of 1.6 × 1012 Jones and photoresponsivity of 76 A W−1 under illumination. This study demonstrates Cu9S5 as a promising p‐type semiconductor for high‐performance p‐n heterojunction diodes. [ABSTRACT FROM AUTHOR]

Objective: To identify trends in physical fitness test scores of college freshmen and their physical fitness from 2018 to 2021, and to analyze the relationship between college students' Body Mass Index (BMI) and Physical Fitness Index (PFI)., Methods: This study obtained physical fitness test data from 7,541 freshmen at a university in Beijing, China, from 2018 to 2021. Analysis of variance (ANOVA) was used to compare the physical fitness indicators among different BMI levels by gender. A nonlinear quadratic regression model was used to evaluate the relationship between BMI and each indicator within gender groups., Results: The BMI of freshmen in China was generally increased over the study period, and BMI levels influenced students' physical fitness indexes to varying degrees. BMI was significantly correlated with the physical fitness indexes and PFI. The increase in BMI had a greater influence on the PFI of males than females., Conclusion: Students with a normal BMI show better physical fitness. A BMI below or above the normal range may result in poor physical fitness. The relationship between BMI and PFI has an inverted u-shaped curve. Physical education programs should be tailored to students with different fitness levels and fundamentals, including but not limited to the development of strength, speed, and other qualities., Competing Interests: Author FY was employed by Li Ning (China) Sports Goods Company Limited. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Guo, Shen, Yang and Yang.)

Strain engineering is a promising method for tuning the electronic properties of two-dimensional (2D) materials, which are capable of sustaining enormous strain thanks to their atomic thinness. However, applying a large and homogeneous strain on these 2D materials, including the typical semiconductor MoS 2 , remains cumbersome. Here we report a facile strategy for the fabrication of highly strained MoS 2 via chalcogenide substitution reaction (CSR) of MoTe 2 with lattice inheritance. The MoS 2 resulting from the sulfurized MoTe 2 sustains ultra large in-plane strain (approaching its strength limit ~10%) with great homogeneity. Furthermore, the strain can be deterministically and continuously tuned to ~1.5% by simply varying the processing temperature. Thanks to the fine control of our CSR process, we demonstrate a heterostructure of strained MoS 2 /MoTe 2 with abrupt interface. Finally, we verify that such a large strain potentially allows the modulation of MoS 2 bandgap over an ultra-broad range (~1 eV). Our controllable CSR strategy paves the way for the fabrication of highly strained 2D materials for applications in devices., Competing Interests: Conflict of interest The authors declare that they have no conflict of interest., (Copyright © 2021 Science China Press. Published by Elsevier B.V. All rights reserved.)