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With the improvement of high complexity and automation level of the aircraft systems，pilots are often ill-prepared to cope with an actual emergency or failure，and their corrective actions may be erroneous，delayed or incomplete. Therefore，there is an urgent need to consider flight crew human factors in system safety assessment. By analyzing the requirements of CCAR25.1309（b）and（c）and failure processing process of flight crew，based on the failure conditions in functional hazard assessment，the methods of requirements capture and analysis of flight crew human factors is proposed. By applying these methods in the aircraft development，the top down design for safety which from failure condition to alert and procedures is achieved，and a complete chain of compliance evidence for human factor of safety is established. The results show that the proposed method can effectively demonstrate airworthiness compliance with human factors of CCAR25.1309 （b）and（c）.

Hyperuricemia (HUA) is a disease caused by excessive production and/or inadequate excretion of uric acid (UA) in the body, and persistent HUA can lead to gout. Asymptomatic HUA is closely related to other metabolic diseases, such as chronic kidney disease, diabetes and cardiovascular disease. Probiotic intervention is a potentially safe, cost-effective treatment to improve HUA. This paper mainly describes the mechanisms of action of probiotics in reducing the level of uric acid, including inhibiting xanthine oxidase activity, absorbing and degrading purines in the intestine, regulating intestinal flora homeostasis and restoring intestinal barrier function. In addition, probiotics can promote uric acid excretion and consequently reduced uric acid levels by promoting the expression of urate transport proteins and inhibiting the expression of urate reabsorbing proteins. Probiotics have great potential in alleviating HUA. This review hopes to provide a theoretical basis for subsequent research.

Cervical cancer continues to be a concern, and the prognosis of locally advanced cervical cancer remains poor. IMPA2 was previously identified as a potential oncogene and regulator of tumor apoptosis. In this study, we aim to further elucidate the underlying mechanisms of IMPA2 gene in the regulation of cervical cancer apoptosis. First, we identify AIFM2 as an upregulated gene in IMPA2-silenced cervical cancer cells, and inhibition of AIFM2 reverses IMPA2 knockdown-induced apoptosis. Further study reveals that AIFM2 regulates cell apoptosis in a mitochondrial-dependent manner with a redistribution of mitochondrial membrane potential and intracellular Ca 2+ levels. However, the analysis of the STRING database and our experimental results show that AIFM2 has little effect on cervical cancer progression and survival. Further mechanistic study demonstrates that IMPA2 and AIFM2 silencing inhibits apoptosis by activating p53. Meanwhile, the knockdown of IMPA2 enhances the chemosensitivity of cervical cancer cells by strengthening paclitaxel-induced apoptosis. Based on the above results, the IMPA2/AIFM2/p53 pathway may be a new molecular mechanism for paclitaxel treatment of cervical cancer and an effective strategy to enhance the sensitivity of cervical cancer cells to paclitaxel. Our findings display a novel function of IMPA2 in regulating cell apoptosis and paclitaxel resistance mediated by a disturbance of AIFM2 and p53 expression, potentially making it a novel therapeutic target for cervical cancer treatment.

The irregular characteristics and geometric randomness of horn-type ice are significant while the behaviors of separation are complex. The mechanism and factor leading to the essential change of stall performance are still not clear. According to actual requirements of airworthiness certification of a large passenger aircraft, a family of horn-type ice shapes with different parameters are constructed based on typical supercritical airfoil and icing environment. By combining with wind tunnel test and numerical simulation methods, the parameter sensitivity of airfoil stall characteristics to the change of ice height and angle is systematically analyzed and the essential influence mechanism of the ice shape parameters leading to the change of separation bubble development under stall process is summarized, which provides a theoretical basis for ice airworthiness certification of large passenger aircraft.

Introduction: Altitudinal changes in soil bacterial diversity, composition, biotic interactions, and function are prevalent. However, the overall patterns and associations among these dimensions remain unclear, particularly in vulnerable alpine mountain ecosystems. Methods: Here, we investigated soil bacterial communities along a high-altitude gradient to elucidate patterns and associations in taxonomic and phylogenetic diversity, co-occurrence networks, and functional potentials. Results: We observed increasing altitudinal trends in bacterial richness and phylogenetic diversity, along with significant differences in taxonomic and phylogenetic composition across altitudes. The connectivity component of the co-occurrence network properties showed a negative association with altitude. We also observed high redundancy in functional potentials, resulting in insignificant variation in functional diversity along the altitudinal gradient. However, the strength of functional diversity varied based on the interaction between network connectivity and phylogenetic diversity. Additionally, functional dissimilarity was more closely associated with phylogenetic rather than taxonomic dissimilarity or differences in network properties, highlighting the role of phylogenetic lineages in functional redundancy. Discussion: This study characterizes the altitudinal distribution of soil bacteria and explores their covariations, enhancing our understanding of soil bacterial diversity and functional potentials along altitudinal gradients and providing valuable insights for predicting community changes and improving alpine ecosystem conservation. [ABSTRACT FROM AUTHOR]

High-speed reducers in electric vehicles, characterized by high rotation speeds, heavy loads, large helix angles, and high contact ratios, are prone to tooth surface scuffing due to high sliding speeds. This scuffing is caused by adhesion wear from excessive instantaneous friction flash temperatures. The prevailing approach to gear scuffing analysis relies on the standard formula method, which is a relatively rudimentary technique. This method lacks the precision required to accurately assess the intricate distribution of tooth surface flash temperature (TSFT), limiting its efficacy in targeted tooth optimization. This study introduces an enhanced semi-analytical method to calculate TSFT and analyzes its variation under different conditions: increased tooth number and reduced module, altered pressure angle, and varied helix angle. The aim is to understand how these geometric parameters affect TSFT and the scuffing load capacity of high-speed reducer gears. This study calculates load distribution and TSFT under peak operating conditions and shows that increasing the tooth number, pressure angle, and helix angle can reduce maximum TSFT by more than 30%, improving scuffing safety and load capacity. However, these improvements must consider the gear's allowable bending safety factor and bearing service life. The research concludes that optimizing these geometric parameters can significantly enhance the scuffing load capacity of gearsets. [ABSTRACT FROM AUTHOR]

Animal body size exhibits rapid responses to environmental variations and displays considerable variability across ecological scales, significantly influencing ecological community assembly. However, our understanding of the extent of body size variation and its responses to environmental differences within soil fauna remains limited, impeding a comprehensive grasp of soil fauna's functional ecology. Here, we aim to investigate the magnitude of intrageneric body size variation and its implications for soil nematode community assembly along an altitudinal gradient. We examined soil nematode body size responses along an altitudinal gradient spanning from 3136 to 4128 m in an alpine mountain region of the eastern Tibetan Plateau. We assessed the contributions of intra‐ and intergeneric variations in body size, both within and among communities, using individual body size values. The implications of these variations for community assembly processes were determined through phenotypic variance ratios employing permutation tests. Our analyses did not reveal statistically significant correlations between altitude and the community‐weighted mean body mass, regardless of considering intrageneric trait variation (IGTV). Approximately 15% of the variation in body size among communities and a substantial 72% of the variation in body size within communities can be attributed to IGTV. Altitude did not significantly affect IGTV within or among communities. Furthermore, our results underscored the dominant role of internal filtering within the community in governing nematode community assembly, with external filtering outside the community playing a limited role within our altitudinal range. Our findings emphasize the dominant role of body size variation within communities rather than among communities, attributable to strong internal filtering processes. These findings advance our understanding of body size variation in soil nematodes across ecological scales and highlight the pivotal role of intrageneric variation in shaping the functional ecology of soil fauna. [ABSTRACT FROM AUTHOR]