Lishui Vocational and Technical College

Bone marrow mesenchymal stem cell-derived exosomes (BMSCs-Exos) with their molecular cargo have therapeutic potential for pulmonary fibrosis (PF). This research was performed to uncover how microRNA-31-5p (miR-31-5p), carried by BMSCs-Exos, affects PF via modulating IGFBP7. C57BL/6 mice were treated with bleomycin (BLM) to induce PF. Pulmonary function was tested, and fibrotic changes in the mouse lung tissues were examined. Levels of fibrosis-related inflammatory factors, including tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6, were tested. Mouse BMSCs were isolated and identified, and BMSCs-Exos were obtained by ultracentrifugation. Exosome morphology was observed by transmission electron microscopy, the surface markers were measured, and the expression levels of BMSCs-Exo marker proteins were assessed. The targeting relation between miR-31-5p and IGFBP7 was assessed, and the expression of both was tested. After modeling, mice exhibited decreased functional residual capacity, lung compliance, inspiratory capacity, vital capacity, total lung capacity, and forced vital capacity. After 14 days of BLM induction, thickening of the main tracheal wall, fibroblast accumulation, immune cell infiltration in lung interstitium, and increased collagen deposition were observed. Elevated levels of TNF-α, IL-1β, and IL-6 were also noted. BMSCs-Exos attenuated BLM-induced PF, and BMSCs-Exo-derived miR-31-5p ameliorated PF in mice. miR-31-5p was shown to target IGFBP7, diminishing both transcript and protein levels. IGFBP7 overexpression reversed the ameliorative impact of miR-31-5p on PF in mice. BMSCs-Exos ameliorate PF development by delivering miR-31-5p to repress IGFBP7.

PurposeThis study examined the associations between perceived PE teacher teaching styles on Chinese middle school students' sports learning engagement, and the mediating roles of classroom satisfaction and psychological resilience.MethodsA cross-sectional survey assessed 1,629 junior and senior high school students in Chengdu and Chongqing, Validated scales measured perceived teaching styles, psychological resilience, sports learning engagement, and PE class satisfaction. SPSS 26.0 was used for correlation, regression, and mediation analyses (SPSS PROCESS v4.1 Macro, Model 4).ResultsPerceived teaching styles were positively associated with sports learning engagement (β = 0.371, 95%CI = 0.343–0.398, p < 0.01). Significant associations emerged for rigorous-logical (β = 0.292, 95%CI = 0.066–0.518, p < 0.05), caring-sharing (β = 0.489, 95%CI = 0.179–0.800, p < 0.01), and innovative-exploratory (β = 0.898, 95% CI = 0.523–1.273, p < 0.01) styles, but not for humorous-active (β = 0.095, 95% CI = −0.092–0.282, p > 0.05).Classroom satisfaction and psychological resilience partially mediated the relationship between teaching style and learning engagement (p < 0.05), with the mediating role of psychological resilience (26.0%) being significantly stronger than that of classroom satisfaction (18.9%).ConclusionThere is a significant positive association between PE teachers‘ teaching styles and students' PE learning engagement. Moreover, classroom satisfaction and psychological resilience play mediating roles in this relationship. Therefore, it is recommended that PE teachers prioritize the adoption of positive teaching styles in PE classroom instruction.

Chemical pesticides have traditionally been a primary strategy for controlling plant diseases. With the mounting issues in disease control arising from the prolonged use of pesticides, the three ″R″ issues (resistance, residues, and resurgence) and the three ″risks″ (disability, teratogenicity, and mutagenicity) have become more prominent, significantly hindering agricultural development. There is an urgent need to develop sustainable and environmentally friendly approaches to prevent and control plant diseases. RNA pesticides are poised to lead a green revolution in agriculture, and spray-induced gene silencing (SIGS), depending on dsRNA and nanotechnology, is a novel approach offering efficient and targeted strategies for sustainable management of plant pathogens. The technology avoids the potential ecological risks associated with genetically modified crops. This review outlines the recent progress in understanding the molecular mechanisms of dsRNA silencing in plant pathogens and focuses on the advancements in SIGS using nanotechnology for managing plant diseases. The combination of SIGS with nanopesticide will provide a dual effect on disease control.

Feline panleukopenia, feline calicivirus infection, feline viral rhinotracheitis, and feline infectious peritonitis are significant diseases that threaten feline health. The trend of mixed infections is increasing, and current diagnostic methods are limited in scope and unable to provide rapid, simultaneous detection of these diseases. Four groups of primers and probes targeting the VP2 gene of Feline Panleukopenia virus (FPV), the TK gene of Feline Herpesvirus (FHV-1), the ORF2 gene of Feline Calicivirus (FCV), and the N gene of Feline Infectious Peritonitis Virus (FIPV) were designed. After optimizing the concentrations of primers and probes and annealing temperature, a quadruplex TaqMan MGB fluorescent quantitative PCR method was established to concurrently detect these four pathogens. Recombinant plasmid standards were constructed to establish standard curves, and the sensitivity, specificity, reproducibility, and clinical application of the assay were evaluated. The optimal final concentrations of primers for FPV, FHV-1, FCV, and FIPV were 0.08, 0.04, 0.06, and 0.12 μM, respectively, and the optimal final concentrations of probes were 0.08, 0.08, 0.12, and 0.12 μM, respectively. The best annealing temperature was 59°C. No cross-reaction was observed with common pathogens in infected cats. The minimal detection limits for recombinant plasmids of T-VP2, T-TK, T-ORF2, and T-N were 50.79, 53.21, 47.91 and 41.25 copies/μL, respectively. The R² values of standard curves are 0.994, 1.0, 0.998 and 0.999, respectively, and high amplification efficiencies of 105.05%, 96.28%, 98.82%, and 96.45%, respectively. The coefficient of variation for inter-batch and intra-batch tests ranged from 0.14 to 1.37%. Among 381 fecal samples from cats, the detection rates for FPV, FHV-1, FCV, and FIPV were 13.65% (52/381), 18.37% (70/381), 26.77% (102/381), and 9.71% (37/381), respectively, with a 100% agreement with previously reported methods and commercial kits. The sensitive, specific, high-throughput, quadruplex TaqMan MGB quantitative fluorescent quantitative PCR method was successfully established for the simultaneous detection of FPV, FHV-1, FCV, and FIPV.

This research assesses practices and legislation about post-mining land utilization in the United States. This paper examines insights from these practices and legislation within the Indonesian legal environment. This study employs a normative legal methodology within a comparative legal framework. The research indicates that the United States’s post-mining land use policies and practices are regulated by the Surface Mining Control and Reclamation Act (SMCRA) and different federal regulations supporting public purposes such as airports, shopping centers, and industrial zones. Rigorous supervision is enforced on post-mining land prior to its designation as appropriate for use. Specialized land management methods are implemented when mining occurs on prime agricultural land. The efficacy of reclamation is significantly contingent upon the use of scientifically substantiated optimal management practices that emphasize ecological restoration and biodiversity enhancement. Longitudinal studies in the United States about ecological reclamation demonstrate that effective strategies, including surface soil replacement and customized planting schemes, markedly enhance the likelihood of successful revegetation of former mining sites. The United States offers a robust framework underpinned by comprehensive policies and efficient implementation that Indonesia can adopt. Future adoption of post-mining land use policies and practices in Indonesia should establish a harmonious equilibrium that fosters sustainable development, preserves environmental integrity, and promotes active community engagement.

Wearable medical devices play an increasingly important role in disease diagnosis and health management, and self-powered sensors based on the triboelectric principle provide new ideas for the development of wearable respiratory monitoring devices. To overcome the unstable shortage of reported triboelectric yarn with a single electrode and two freestanding electrodes, this work designed a coaxially braided triboelectric-sensing thread (CBTT) with a braided mesh spacer separating two-electrodes, which potentially meets the daily and long-term stable monitoring of human respiratory movements, and the effects of the braiding parameters of the mesh spacer on the performance of the CBTT were discussed. The results show that both the braiding process parameters of the mesh spacer and the specification of the mesh-braiding yarn affect the performance of the prepared CBTT. Among them, CBTT prepared by nylon monofilaments with a diameter of 0.2 mm and a 30° on-machine braiding angle had the best sensing performance under the designed strain range. In addition, for the respiratory state monitoring, the output response and the accuracy of CBTT with a mesh spacer are highest among three kinds of the studied sensing yarns with coaxially braiding structure. These results indicated the stable structure advantage of the seamless integration of a mesh spacer into the coaxially braiding two-electrodes triboelectric sensing yarn and brings new tools for user-friendly health monitoring.

The flow occurring at the bottom of a polycrystalline diamond compact (PDC) drill bit involves a complex process made up of drilling fluid and the drilled rock cuttings. A thorough understanding of the bottom-hole flow conditions is essential for accurately evaluating and optimizing the hydraulic structure design of the PDC drill bit. Based on a comprehensive understanding of the hydraulic structure and fluid flow characteristics of PDC drill bits, this study integrates computational fluid dynamics (CFD) with rock-breaking simulation methods to refine and enhance the numerical simulation approach for the liquid–solid two-phase flow field of PDC drill bits. This study further conducts a comparative analysis of simulation results between single-phase and liquid–solid two-phase flows, highlighting the influence of rock cuttings on flow dynamics. The results reveal substantial differences in flow behavior between single-phase and two-phase conditions, with rock cuttings altering the velocity distribution, flow patterns, and hydraulic performance near the bottom-hole region of the drill bit. The two-phase flow simulation results demonstrate higher accuracy and provide a more detailed depiction of the bottom-hole flow, facilitating the identification of previously unrecognized issues in the hydraulic structure design. These findings advance the methodology for multiphase flow simulation in PDC drill bit studies, providing significant academic and engineering value by offering actionable insights for optimizing hydraulic structures and extending bit life.

Abstract With the rapid development of UAV industry, autonomous UAV obstacle avoidance navigation has become a core problem in the field of UAV control. Based on recurrent neural networks, this paper proposes an LSTM-enhanced Layered-RSAC algorithm to construct a collaborative task execution and autonomous navigation system for UAV swarms. By constructing the autonomous navigation system of UAV, its accuracy is tested and the UAV operation situation index is examined. Through model training, the standard deviation of the a priori strategy with the best success rate of autonomous navigation is explored. The a priori strategy σ = 0.45 is taken as the initial value to verify the performance improvement of the Layered-RSAC algorithm. The results show that the Layered-RSAC algorithm reaches 90% navigation success rate at 50 training steps for the first time and stabilizes at 90% to 100% success rate after 100 training steps, which is significantly ahead of Prior-Policy, DDPG and SAC algorithms.

在我国产业升级的大背景下，高职教育肩负着培养技术技能型人才的重任，同时也承担着工匠精神传承与创新的使命。针对高职金工实训中工匠精神的传承与创新存在的学生内驱力不足、教学中忽视工匠精神元素发掘的问题，提出了在工匠精神的传承与创新中，以榜样的示范作用激励学生，并在教学中发掘工匠专注、严谨、精益、创新等工匠精神元素，多维度培养工匠精神，将工匠精神的传承扎根于金工实训教学全过程，为新时代“大国工匠”培养提供参考。Against the backdrop of industrial upgrading in our country, vocational education shoulders the responsibility of cultivating technical and skilled talents, as well as the mission of inheriting and innovating the spirit of craftsmanship. In response to the problems of insufficient internal motivation among students and neglect of the exploration of craftsmanship elements in vocational metalworking training, this paper proposes that in the inheritance and innovation of craftsmanship spirit, students should be motivated by the exemplary role of role models, and craftsmanship spirit elements such as focus, rigor, lean, and innovation should be explored in teaching to cultivate craftsmanship spirit from multiple dimensions. The inheritance of craftsmanship spirit should be rooted in the entire process of metalworking training teaching, providing reference for the cultivation of “great country craftsmen” in the new era.