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BACKGROUND: Studies have shown that short-chain fatty acids (SCFAs) are a potential regulator of skeletal muscle energy metabolism, but the exact mechanism is unclear. OBJECTIVE: To observe the effect of SCFAs on aged rats with sarcopenia and to explore the underlying mechanism. METHODS: Sprague-Dawley rats were randomly divided into control group, sarcopenia group, and sarcopenia + SCFAs group (SCFAs group). In the latter two groups, rat models of sarcopenia were established using ovariectomized rats injected with 5 mg/kg dexamethasone for 7 days. In the control group, the abdominal cavity was only exposed but not removed, and then sutured. Rats in the SCFAs group were administered drinking water containing 150 mmol/L short-chain fatty acids, 600 mg/kg sodium acetate, 200 mg/kg sodium propionate, and 200 mg/kg sodium butyrate for 4 weeks. Rats in the control and sarcopenia groups were given the same volume of normal saline. Successful modeling was assessed by measuring the bilateral gastrocnemius muscle mass and body mass to calculate the gastrocnemius index after modeling. Food intake, body mass and grip strength of rats were measured at 0, 1, 2 and 4 weeks after successful modeling; morphological changes of gastrocnemius muscle were observed by hematoxylin-eosin staining; and the expression of p-AMPK and p-ULK1 proteins in gastrocnemius muscle was detected by western blot. RESULTS AND CONCLUSION: Compared with the control group, the sarcopenia group showed significantly decreased body mass, food intake, forelimb grip strength (P < 0.05), wet mass of gastrocnemius muscle (P < 0.05), and protein levels of p-AMPK and p-ULK1 (P < 0.05). Compared with the sarcopenia group, the SCFAs group showed a significant increase in food intake, body mass, grip strength, wet mass of gastrocnemius muscle, and protein levels of p-AMPK and p-ULK1 in gastrocnemius muscle (P < 0.05). All these findings indicate that SCFAs improve symptoms of sarcopenia in the elderly and may be associated with the upregulation of AMPK and ULK1 proteins in skeletal muscle. [ABSTRACT FROM AUTHOR]

Objective Based on the Gene Expression Omnibus （GEO） database, our aim is to identify potential mitophagy-related genes for sarcopenia and to observe their expression changes in skeletal muscle tissues of patients with sarcopenia. Methods Gene expression datasets for sarcopenia （GSE1428） were obtained from the GEO database and differentially expressed genes （DEGs） in the sarcopenia samples and normal samples were screened. The DEGs of sarcopenia were intersected with mitophagy-related genes using the "VennDiagram" package to obtain mitophagy-related DEGs of sarcopenia. The biological functions of mitophagy-related DEGs for sarcopenia were analyzed using Gene Ontology （GO） and Kyoto Encyclopedia of Genes and Genomes （KEGG). The mitophagy-related target genes for sarcopenia were selected using Cytoscape, and the expression changes of these genes in skeletal muscle tissues of patients with sarcopenia and controls were observed in the gene expression datasets GSE136344 for sarcopenia. Results Ninety-nine mitophagy-DEGs for sarcopenia were screened out. As shown by KEGG enrichment analyses, these genes were significantly enriched in pathways responsible for neurodegeneration-multiple diseases, Parkinson's disease, prion disease, and so on. GO function annotation showed that DEGs were mostly located in the mitochondrial inner membrane and mitochondrial protein-containing complex, where they were engaged in biological processes such as energy metabolism, cellular respiration, and oxidative phosphorylation. They were also involved in the molecular functions of active transmembrane transporter activity, etc. The inner membrane mitochondrial protein （IMMT), dynamin 1-like （DNM1L), and ATP5A1 were identified as the mitophagy-related target genes for sarcopenia. Sarcopenic patients exhibited lower expression levels of IMMT and DNM1L in their skeletal muscles in comparison with non-sarcopenic individuals （all P<0. 05). Conclusions IMMT and DNM1L were identified as significant mitophagy-related target genes for sarcopenia. These target genes contributed to the pathogenesis of Sarcopenia not on‐ ly by affecting neurodegeneration-multiple diseases pathways, Parkinson's disease pathway, and prion disease pathway but also by participating in biological processes such as energy metabolism, cellular respiration, and oxidative phosphorylation. Patients with sarcopenia exhibited lower expression levels of IMMT and DNM1L in skeletal muscle tissues. [ABSTRACT FROM AUTHOR]

This study was carried out to investigate the impact of two litter remaining characteristics of six typical vegetation communities in urban green spaces on the physicochemical properties of the soil. Typical vegetation communities in Yuantouzhu Park were selected as the research area, and the litter amounts of those vegetation communities in the urban green spaces and their responses to the soil physicochemical properties were studied. The results showed that the annual litter amounts of the tree-shrub-ground cover, tree-lawn, tree-ground cover, and tree-shrub-lawn communities were significantly higher (P<0.05) than those of the shrub-ground cover and shrub-lawn communities. The litter standing stock, total soil porosity, non-capillary porosity, and soil organic matter, total N, and hydrolyzed N contents of the coverage from the tree-shrub-ground cover, tree-ground cover, and shrub-ground cover communities were all significantly higher than those of the coverage from the tree-shrub-lawn, tree-lawn, and shrub, lawn communities. Soil bulk density of tree-shrub-ground cover, tree-ground cover, and shrub-ground cover communities were all significantly lower than it of tree-shrub-lawn, tree-lawn, and shrub-lawn communities. Although there were some significant differences in the soil capillary porosity, pH value, and total P content among the six communities, there were no differences in the total K and available K contents. According to the correlation analysis, the annual litter in the communities had no correlation with the indicators of the physicochemical properties of soil at 0-10 cm. By contrast, the litter standing stock was closely related to the soil physicochemical properties, that is, its value was significantly negatively correlated with the soil bulk density (P<0.01) and pH value (P<0.05) and significantly positively correlated with the total soil porosity, non-capillary porosity, soil organic matter, total N content, hydrolyzed N value (P<0.01), and available K content (P<0.05) and had no correlation with the soil capillary porosity and total P and total K contents. These results indicated that litter on the surface cover of urban green spaces can directly or indirectly improve the soil physicochemical properties as well as the soil water holding capacity and permeability. Increasing soil organic matter and N contents can also improve the soil pH value. [ABSTRACT FROM AUTHOR]

Objective To investigate the current status of personal control perception in patients undergoing total hip arthroplasty (THA) and analyze its influencing factors. Methods A total of 302 patients undergoing THA from three tertiary hospitals in Urumqi were surveyed using general information questionnaires, self-efficacy for rehabilitation exercise, health belief, social support, hip joint function, and personal control perception scales. Results The average score of personal control perception in patients undergoing THA was (24.09±5.11) points. Regression analysis showed that age, educational level, health belief score, pain score, social support score, self-efficacy score, and hip joint function score were influencing factors of personal control perception in patients undergoing THA. Conclusion Younger age, higher educational level, higher health belief level, lower pain intensity, higher self-efficacy for rehabilitation exercise level, better social support level, and better recovery of hip joint function were associated with better personal control perception in patients undergoing THA. Healthcare providers should develop personalized intervention measures based on these influencing factors to improve patients′ personal control perception and thereby enhance the rehabilitation outcomes of patients undergoing THA. [ABSTRACT FROM AUTHOR]

目的 探讨慢性肾脏病管理模式对慢性肾脏病伴高尿酸血症患者的影响。方法 选取该院 2016 年 4 月至2017 年 4 月收治的82例慢性肾脏病伴高尿酸血症患者进行分组比较,给予慢性肾脏病管理模式者纳入观察组,给予常规疾病管理者 纳入对照组,每组各 41 例。结果 干预后, 2 组尿酸水平均有所下降, 且观察组的尿酸水平显著低于对照组,差异有统计学意义 (P <0.05)。干预后,观察组的高嘌呤饮食者比例均显著低于对照组, 且观察组的运动者比例显著高于对照组, 差异有统计学意 义(P <0.05)。干预后观察组的肌酐、尿素氮及 24 h 尿蛋白定量与对照组相比具有明显改善,差异有统计学意义 (P <0.05)。结 论 临床将慢性肾脏病管理模式应用到慢性肾脏病伴高尿酸血症患者护理管理工作中, 可提升患者自我管理水平, 纠正不良生活 习惯,故有进一步推广的价值。 [ABSTRACT FROM AUTHOR]

目的 探讨同伴教育在护理学基础技能培训中的应用及效果。 方法 选取该校2013级高职护理专业（普招班）11个班中随机抽取2个班116名学生作为研究对象，将其分为实验组和对照组，各58名。实验组学生采取同伴教育法，对照组采用传统教学法。操作复习后进行技能考核，对考核效果进行评价。 结果 实验组学生操作考核成绩明显优于对照组，差异有统计学意义（χ2=19.90，P<0.01）；且实验组学生各项目成绩均明显高于对照组，差异均有统计学意义（P<0.05）。 结论 在护理学基础技能培训中使用同伴教育法，可取得良好的教学效果，也可激发学生的学习积极性，提高沟通能力及团队合作精神。 [ABSTRACT FROM AUTHOR]

Aiming at the problem that electric arc was difficult to extinguish in the process of DC circuit breaker interrupting, the interrupt characteristics of the DC circuit breaker were analyzed. How to shorten the combustion time of the arc was analyzed by this paper, and the in­fluence of the time constant on the breaking capacity of the circuit breaker, the rising rate of the arc current and the relationship between the current of the breaker and the arcing time was studied. Based on the above analysis, created a prototype, and open circuit was tested for many times by using high voltage DC test rig simulation about different short circuit fault current of DC circuit breaker, won a lot of experi­mental data. The results show that the circuit breaker in the rated voltage is DC 1800 V, which can reliably remove fault current to 80 kA, circuit breaker fault current decreases with time constant, arcing time decreases with the increase of breaking current. [ABSTRACT FROM AUTHOR]

Traditional hammer mill generally has the problem that the screening efficiency is lower than the grinding efficiency. In order to improve the screen efficiency of the hammer mill, based on the combination of experiment and numerical simulation method, the influence of the structure parameters of the hammer mill screen and the air flow velocity in the separation device on the screening efficiency was studied, the mechanism of screening was revealed, and the way to improve the screening efficiency of the crusher was explored. According to a type of hammer mill designed by research group, we designed a screening test bench to simulate the air flow field in the separation device of the hammer mill using a blower as the air flow source. In this experiment, 5 kinds of particle sizes through screen were selected, and the influences of 4 factors including the screen hole shape, the screen installation angle, the screen hole arrangement and the air flow velocity on the particle screening efficiency were investigated. In the experiment, 10 kinds of screens were adopted, which were composed of 5 kinds of screen hole shapes and 2 kinds of screen hole arrangements, and there were 11 screen installation angles and 8 kinds of air flow velocity levels selected. The 5 kinds of screen holes were the rectangular hole, the oblong hole, the hexagonal hole, the square hole and the circle hole. The 2 kinds of screen arrangements included "U" type and "T" type arrangement. The experiment showed that the screening efficiency was high and then became low after the air velocity increased; the screen hole shape and screen installation angle had lager effect on the screening efficiency; the arrangement of the screen holes had less effect on the screening efficiency. Also the EDEM-FLUENT software was used to simulate the process of particle screening; the simulation and the experiment results were basically consistent, and the relative error of the two was not more than 4%. Based on this, the research found the optimum combination of the structure parameters and the flow parameters of the screen: when the air flow rate was 6-15 m/s, the screen efficiency of the material was gradually increasing and then decreasing; when the air flow velocity was 6-7 m/s, the phenomenon of material passing through screen was not obvious, mainly because air was not sufficient to drive the movement of particles when the material was under the influence of gravity; when the air flow velocity was more than 7 m/s, the screen efficiency increased, and when air flow speed reached 12.37 m/s, the screening efficiency reached the optimal value, but when the air flow speed continued to increase, the screening efficiency decreased; when the air flow velocity reached 14.21 m/s, the air flow began to negatively impact the particles passing through the screen and the screening efficiency decreased. This was because when the energy of air flow was greater, the particle reached the screen panel with greater speed for the first time, and if they first failed to pass through the screen, they would hit the screen surface to rebound, thereby reducing the secondary screen penetration probability. When the screen installation angle was in the range of 20°-70°, the screening efficiency decreased with the screen installation angle, and the best screen installation angle was 35°-45°; if the screen's opening rate was the same, the screening efficiency of the rectangular hole was the highest among the 5 kinds of screens, and the screening efficiency of circle hole was the lowest of all; the screen hole arrangement had little influence on the screening efficiency. Results suggest that when the air flow velocity was 12.37 m/s, and the screen installation angle was 40°, the rectangular "T" type arrangement had the highest screening efficiency of 0.72-0.74. [ABSTRACT FROM AUTHOR]

In order to test the flow field of the mill, the project group proposed a new method based on virtual instrument technology, and constructed a set of test system according to the method, which coverd the design of the instrument selection, data acquisition, data analysis and processing. In the program design process, we designed an integrated virtual digital filter using the powerful data and signal analysis tools in Lab VIEW, which covers 6 kinds of commonly used digital filters. Taking a new type of mill prototype as the experimental object, the project group carried out many test experiments on the single air flow field and the air and solid two-phase flow field in the chamber. Firstly, the pressure and velocity of the air flow field in A section were tested by 2 kinds of test methods and the single flow field of the whole chamber was simulated and analyzed. Through the comparison, the result showed that the error was in the 5% and the 3 ones were consistent with each other. Secondly, when the speed was constant, the pressure distribution of the flow field near the wall under the condition of no load and load was consistent with that of the flow field near the wall. Thirdly, the influence of material concentration on the flow field near the wall was not obvious at the 1000, 1500, 2000 and 2500 r/min rotating speed of the air flow field, the effective value of the pressure decreased with the increase of the speed, and the air-solid two-phase flow had the same law. The effective value of the pressure in the corresponding test point was reduced. In air flow field, the pressure value of less than or equal to 1500 r/min was positive. This showed that in the work, the low speed of the pressure field was small, and the negative pressure of the back was small. Besides, rotation speed of the mill had a great influence on negative pressure, when the speed changed from 1000 to 2500 r/min, and the maximum negative pressure of test was from-20.35 to-411.15 Pa. The negative pressure calculated by back propagation(BP) neural network algorithm was from-37.24 to-678.42 Pa. The effect of material on the flow field near the wall was not much, but it would weaken the negative pressure in the center area. The sealing performance of the mill had great influence on the internal flow field. Under the 2500 r/min work condition, so the theoretical maximum negative pressure was-2.5 KPa, and the test maximum negative pressure was only-411.15 Pa. Therefore, the method and the measuring system provide the technical support for the following study on the relationship between the pressure and the structural parameters of the mill, and provide the theoretical basis for the optimization design of the new type of mill. [ABSTRACT FROM AUTHOR]