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The water accumulation in goaf and coal rock interaction will weaken the strength of the coal pillar in the section and cause gradual destruction and failure of the coal pillar. The interaction of water and rock is the key factor that must be considered in the design of the reasonable width of the coal pillar. The uniaxial compression experiment and theoretical analysis are carried out based on the engineering background of the coal pillar design between mining area 31 and 33 of a mine in Xinjie mining area, Ordos, Inner Mongolia. The results show that water-rock interaction has a significant impact on the weakening of coal strength parameters. The width of the plastic zone at the side of the water accumulation in the section coal pillar expands with the increase of the weakening degree of the coal body strength. Based on the basic conditions for the stability of the section coal pillar, the reasonable theoretical width of the section coal pillar is 53.62 m. Using FLAC3D to simulate the process of water-rock interaction, the paper analyzes the stability characteristics of coal pillar with different widths. The results show that when the width of the coal pillar is small, the weakening effect of water accumulation in goaf has stronger destructive capability to the elastic core area with higher stress concentration. With the increase of coal pillar width, the stress concentration degree in the elastic core area decreases. The area where the vertical stress at the water accumulation side of the goaf is lower than that of the original rock increases. The stress concentration distribution on both sides of the coal pillar tends to be uniform, and the weakening effect of water accumulation in the goaf on the elastic core area is no longer significant. Based on the results of theoretical calculation and numerical simulation, the width of coal pillar is determined to be 70 m. The engineering application results show that the coal pillar with width of 70 m can effectively bear the roof pressure. The deformation of the roadway surrounding rock is small, the stress of the anchor cable is stable, and the safety production of the mine is guaranteed.

With the development of China's economy, the aging of the population is becoming more and more prominent, and China will enter a stage of deep aging. With the development of social economy and social progress, China's urban residents have put forward higher requirements for social and economic development. Judging from the survey results in recent years, the currently designed buildings are not suitable for the elderly to live in, which is not conducive to improving the quality of life of the elderly. This paper firstly introduces the influencing factors of modern pension building space design, then states the principles of pension building space design, and finally describes the problems and solutions existing in the current design of pension buildings under the concept of ageing.

Objective To explore the protective effect of β-caryophyllene (BCP) on cerebral ischemia-reperfusion (I/R) rats and related mechanism. Methods SD rats were randomized into sham operation group, I/R group, and low-, medium- and high-dose BCP groups (102, 204 and 408 mg·kg-1), Jagged1 (Notch1 agonist, 50 mg·kg-1 in 3 h before I/R injury)+BCP group, and Jagged1 group. The treatments were given to the corresponding rats through intragastric infusion. In 7 d later, SD rat CIR model was established with suture-occlusion, with ischemia for 1.5 h followed by reperfusion for 48 h. The infarct volume and neurobehavioral score were measured; Western blotting was used to detect the cerebral protein levels of Notch1, NF-κB p65, NF-κB p-p65 and Hes1; HE staining was applied to observe the number of dead cells, and ELISA was employed to detect the changes of TNF-α and IL1-β contents in the ischemic hippocampus. Results BCP treatment could significantly improve the neurological deficit, reduce the infarct volume, down-regulate the protein levels of Notch1, NF-κB and Hes1 in the hippocampus (P < 0.05), reduce the releases of TNF-α and IL-1β (P < 0.05), and attenuate the death of hippocampal neuronal cells in the rats after cerebral I/R injury. Comparing the simple Jagged1 intervention group, Notch1 agonist, Jagged1, could antagonize the therapeutic effects of BCP. Conclusion BCP can attenuate cerebral I/R injury in rats, and exerts its protective effect probably through inhibiting Notch1/NF-κB signal axis to reduce the release of inflammatory factors.

Due to the semiconductor properties and the weak charge transfer ability, the further application of spinellide material will be hindered in energy storage. Herein, the NiCo2S4 prepared by the two‐step method is modified adopting Se powder with different mass ratios under aqueous solvothermal conditions. Thanks to the selenide formed on the surface, the Se‐NiCo2S4‐10 sample exhibits a specific capacitance of 713 F g−1 at the current density of 1.0 A g−1, which is 2.6 times higher than that of pure NiCo2S4. Commercially, the assembled asymmetric supercapacitors Se‐NiCo2S4‐10//AC present an energy density of 25.13 Wh kg−1 under the power density of 753.9 W kg−1. This work shows that surface selenization has the effect of reducing charge transfer on spinel‐like nanomaterials, which provides a modified idea for the application of spinel materials in supercapacitor electrodes. [ABSTRACT FROM AUTHOR]

Objective To investigate the protective effect of β-caryophyllene (BCP) against ischemic stroke injury in mice and clarify whether such protective effects are associated with miR-183 and nuclear factor-κB (NF-κB) expression. Methods Ninety male C57BL/6 mice were randomized equally into 3 groups, namely the sham-operated group, ischemia-reperfusion (I/R) model group, and BCP (72 mg/kg) pretreatment group. The mice in the latter 2 groups were subjected to middle cerebral artery occlusion for 60 min followed by reperfusion for 24 h. The neurological deficits and infarct volume of the mice were measured, and the pathological changes in the brain tissues were observed using HE and Nissl staining. The expression of miR-183, NF-κB, p-NF-κB, interleukin-1β (IL-1β), and IL-6 in the brain were detected, and the targeting relationship between miR-183 and NF-κB was determined. In the in vitro experiment, the cortical neurons isolated from the brain of neonatal mice were divided into normal group, oxygen-glucose deprivation (OGD) group, and OGD group with 10 μmol/L BCP pretreatment. Immunofluorescence assay was employed for morphological observation of the neurons, and the cell injury was assessed with lactate dehydrogenase (LDH) leakage assay. The expression levels of miR-183, IL-1β, IL-6 and NF-κB in the neurons were measured. Results In the mouse models of ischemic stroke, BCP pretreatment significantly improved neurologic deficit score, reduced the infarct volume, lessened pathological changes of the brain tissue, and decreased the number of Nissl-positive cells in the cortex (P < 0.05). BCP pretreatment significantly upregulated the expression of miR-183 in the brain tissues of the mice (P < 0.05). In the in vitro experiment, BCP pretreatment produced obvious protective effect on neurons and significantly lowered neuronal death rate following OGD (P < 0.05). BCP treatment significantly upregulated the expression of miR-183, inhibited NF-κB activation and lowered the expressions of inflammatory factors in the neurons (P < 0.05). Conclusion BCP protects the brain tissues against ischemic stroke injury by upregulating the expression of miR-183, which inhibits NF-κB activation and lowers the release of inflammatory factors to alleviate inflammation in the brain.

Thin-walled box-shaped tubes, which feature good energy absorption and have a wide range of applications, can be flexibly combined with various buffer materials to form a combined energy consumption structure; However, in view of the complexity of the buffer forms when subjected to axial compression, there is still much room for intensive study in the calculation of the folding method, energy consumption and average force of the tube body during axial crushing. Based on the folding mode and spatial buckling behavior theory of box-shaped tube under axial compression, it not only sorts out the literature on the establishment and improvement process of super-folding theory, but also makes a comparison and analysis of the advantages and disadvantages of the classical method in the calculation of critical buckling force of box-shaped tubes. Moreover, it gives an overview on the common application methods of tube engineering and theoretical progress in terms of the application of box-shaped tubes, as well as makes a summary of the prospect and improvement of box section tube application in civil engineering at the end in this paper.

Stepping up legislation in the foreign-related field is a foundation and prerequisite for advancing the rule of law in domestic and foreign-related affairs in a coordinated manner. It is also an important link in the promotion of the socialist legal system with the Constitution as the core, as proposed in the Report to the 20th National Congress of the Communist Party of China (CPC). Since China introduced the reform and openingup policy in 1978, China's legal system in the foreign-related field has evolved from initial formulation to mature framework, and China's legislation in the foreignrelated field has maintained distinct Chinese characteristics and contemporary features. Currently, China's legislation in the foreign-related field focuses on national security and on high-level opening-up. It continuously strengthens the connection of the rule of law in domestic affairs with that in international affairs, and consistently promotes the China's legal system of extraterritorial application. Furthermore, legislation in the foreign-related field in China still has issues to address, which include the inconclusive status of international treaties within the legal system, a relatively conservative domestic approach in exercising extraterritorial jurisdiction, and a limited scope of legal liability. To better respond to the need of legislation in building a human community with a shared future and to enhance China's right to international legal discourse in global governance, China needs to move faster to introduce the Law on Foreign Relations of the People's Republic of China. This law should reflect the basic positions, principles, and policies that China upholds in matters of foreign relations, as highlighted in the Report to the 20th CPC National Congress. Furthermore, China should continue to improve legislation in key areas of national security and increase the preexisting punitive measures for responding to actions that harm national security both domestically and internationally. Legislation should also be strengthened to counter sanctions and interference, and supporting measures should be adopted to ensure the effect of relevant legislation. In the field of foreign economic and trade relations, China should incorporate highstandard international economic and trade rules in relevant legislations, and should legalize the replicable and promotable legal rules in the building of free trade zones. Additionally, the existing jurisdictional system and international commercial dispute resolution system should be promoted. [ABSTRACT FROM AUTHOR]

This study examined the associations among physical education students' perceptions of their teachers' autonomy-supportive and controlling interpersonal styles, need satisfaction and need frustration, and indices of psychological well-being (subjective vitality) and ill-being (negative affect). The results from 591 Chinese secondary school students in Hong Kong indicated that the relationship between students' perceptions of autonomy-supportive teaching behaviors and subjective vitality was primarily mediated by need satisfaction, whereas the relationship between perceived controlling teaching behaviors and negative affect was primarily mediated by need frustration. The results obtained from the multi-group structural equation model also suggested that these relationships were invariant across sex.