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基于有序Logistic回归模型的北京高校男生有氧能力

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科学技术与工程 2024年第16期24卷 6659-6666页

作者：李闯涛高晓嶙王昊王文迪国家体育总局体育科学研究所北京100061

为探索北京高校男生有氧能力的影响因素,通过随机抽样法抽取134名18~25岁北京高校男生,空腹抽静脉血测血液指标,用德国MetaMax 3B系统实时监测气体代谢,通过线性递增方案测得最大摄氧量(maximum oxygen uptake, VO_(2max))相对值。采用S... 详细信息

为探索北京高校男生有氧能力的影响因素,通过随机抽样法抽取134名18~25岁北京高校男生,空腹抽静脉血测血液指标,用德国MetaMax 3B系统实时监测气体代谢,通过线性递增方案测得最大摄氧量(maximum oxygen uptake, VO_(2max))相对值。采用Spearman相关、有序Logistic回归等分析方法进行分析处理。结果表明:回归方程中影响北京高校男生有氧能力的因素有体重(M)、心率(heart rate, HR)、每搏输出量(stroke volume, SV)、心室射血时间(ventricular ejection, VET)、血红蛋白(hemoglobin, HGB)。方程模型系数综合检验步(step)、块(block)、模型(model)检验的P均小于0.01;拟合优度检验的-2对数似然值(-2LL)为159.374,Cox&Snell R^(2)为0.331,Nagelkerke R^(2)为0.373;方程预测等级1准确率为45.5%,等级2准确率为100%,等级3准确率为100%,综合为81.8%,说明Logistic回归模型性能良好。Hosmer和Lemeshow检验预测值与观望值无显著性差异(P>0.05)。可见北京高校男生定量负荷心功能、血液指标与有氧能力的多元Logistic回归模型拟合度较好,且HR、SV、VET、HGB是预测北京高校男生有氧能力的重要因素。同时研究中受试者无需运动至极限状态,运动强度大大降低,可以有效避免运动风险的发生,回归模型的检验结果良好,适合在大样本人群中推广。

关键词：有氧能力生长和发育运动男生有序Logistic回归模型

维普期刊数据库

Core shift limitation in investment casting process of hollow turbine blade

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Chinese Journal of Aeronautics 2024年第8期37卷 513-526页

作者： Kang CUI lin JING Ruisong JIANG Longnv YU xiao gao Automation and Software Engineering Shanxi UniversityTaiyuan 030006China Key Laboratory of High Performance Manufacturing for Aero Engine Ministry of Industry and Information TechnologySchool of Mechanical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China School of Mechanical Engineering Sichuan UniversityChengdu 610065China

The deviation in wall thickness caused by core shift during the investment casting process significantly impacts the strength and service life of hollow turbine *** address this issue,a core shift limitation method is developed in this ***,a shift model is established based on computational fluid dynamics and motion simulation to predict the movement of the ceramic core in investment casting ***,utilizing this model,an optimization method for fixturing layout inside the refractory ceramic shell is devised for the ceramic *** casting experiment demonstrates that by utilizing the optimized fixture layout,not only can core shift during the investment casting pouring process be effectively controlled,but also the maximum wall thickness error of the blade can be reduced by 42.02%.In addition,the core shift prediction is also validated,with a prediction error of less than 26.9%.

关键词： Hollow turbine blade Wall thickness Ceramic core Shift prediction Fixturing layout optimization

An Updated GA Signaling ＇Relief of Repression＇ Regulatory Model

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Molecular Plant 2011年第4期4卷 601-606页

作者： Xiu-Hua gao Sen-lin xiao Qin-Fang Yao Yu-Juan Wang Xiang-Dong Fu State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing100101 China

Gibberellic acid （GA） regulates many aspects of plant growth and development. The DELLA proteins act to restrain plant growth, and GA relieves this repression by promoting their degradation via the 26S proteasome pathway. The elucidation of the crystalline structure of the GA soluble receptor GID1 protein represents an important breakthrough for understanding the way in which GA is perceived and how it induces the destabilization of the DELLA proteins. Recent advances have revealed that the DELLA proteins are involved in protein-protein interactions within various environmental and hormone signaling pathways. In this review, we highlight our current understanding of the ＇relief of repression＇ model that aims to explain the role of GA and the function of the DELLA proteins, incorporating the many aspects of cross-talk shown to exist in the control of plant development and the response to stress.

关键词： GA DELLA repression cross-talk interaction.

Effect of N-Doping on Absorption and Luminescence of Anatase TiO_(2) Films

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Chinese Physics Letters 2012年第2期29卷 204-207页

作者： XIANG Xia SHI xiao-Yan gao xiao-lin JI Fang WANG Ya-Jun LIU Chun-Ming ZU xiao-Tao Department of Applied Physics University of Electronic Science and Technology of ChinaChengdu 610054 Institute of Mechanical Manufacture Technology China Academy of Engineering PhysicsMianyang 621900

Anatase TiO_(2) films are deposited on glass substrates at different oxygen partial pressures of 0.8-1.6 *** temperature N ion implantation is conducted in the films at ion fluences up to 5 × 10^(17) ions/cm^(2).UV-visible absorption and photoluminescence (PL) are *** the increase of N ion fluences,the band gap of TiO_(2) decreases and the absorbance increases.X-ray photoelectron spectroscopy (XPS) confirms the formation of O-Ti-N nitride after implantation,resulting in the red shift of the band *** PL intensity of the deposited films increases with the increasing oxygen partial pressure and decreases remarkably due to the irradiation defects induced by ion implantation.

关键词： implantation fir visible

Metabolomic Analysis in Saliva and Different Brain Regions of Older Mice with Postoperative Delirium Behaviors

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Biomedical and Environmental Sciences 2024年第2期37卷 133-145页

作者： LIU xiao CAO Ying lin xiao Wan gao Dan Yang MIAO Hui Hui LI Tian Zuo Department of Anesthesiology Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China

Objective Postoperative delirium(POD)has become a critical challenge with severe consequences and increased incidences as the global population ***,the underlying mechanism is yet *** study aimed to explore the changes in metabolites in three specific brain regions and saliva of older mice with postoperative delirium behavior and to identify potential non-invasive *** Eighteen-month-old male C57/BL6 mice were randomly assigned to the anesthesia/surgery or control *** tests were conducted 24 h before surgery and 6,9,and 24 h after *** C3(C3)and S100 calcium-binding protein B protein(S100beta)levels were measured in the hippocampus,and a metabolomics analysis was performed on saliva,hippocampus,cortex,and amygdala *** In total,43,33,38,and 14 differential metabolites were detected in the saliva,hippocampus,cortex,and amygdala,respectively.“Pyruvate”“alpha-linolenic acid”and“2-oleoyl-1-palmitoy-snglycero-3-phosphocholine”are enriched in one common pathway and may be potential non-invasive biomarkers for *** changes were observed in the three brain regions,with the upregulation of 1-methylhistidine and downregulation of *** Dysfunctions in energy metabolism,oxidative stress,and neurotransmitter dysregulation are implicated in the development of *** identification of changes in the level of salivary metabolite biomarkers could aid in the development of noninvasive diagnostic methods for POD.

关键词： Metabolomic Postoperative delirium(POD) Mechanism Biological marker

维普期刊数据库

A surgical alternative of fusiform penetrating keratoplasty for the management of severe infectious keratitis

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1431-1436页

作者： xiao-lin Qi Li-Chao Wang Miao-lin Wang Hua gao Eye Hospital of Shandong First Medical University State Key Laboratory Cultivation BaseShandong Provincial Key Laboratory of OphthalmologyShandong Eye InstituteShandong First Medical University&Shandong Academy of Medical SciencesJinan 250021Shandong ProvinceChina

AIM:To describe the surgical procedure of fusiform penetrating keratoplasty(FPK)using multiple trephines of different sizes for treating patients with severe infectious ***:Fourteen eyes underwent FPK,and 15 eyes received conventional penetrating keratoplasty(PK)were included in the *** best-corrected visual acuity(BCVA),refractive outcomes,endothelial cell density,and postoperative complications were ***:The FPK group was followed for an average of 15.3±2.1mo,whereas the PK group was followed for 16.1±*** corneal ulcers were elliptical-shaped in all 14 eyes in the FPK *** mean BCVA(logMAR,0.26±0.13)showed no statistically significant differences from that in the PK group(logMAR,0.21±0.12,P>0.05)at 1y after *** the mean curvature,mean astigmatism,and mean spherical equivalent in the FPK group were lower than those in the PK group(P<0.05).Peripheral anterior synechia was observed in one patient in the FPK group,whereas 6 patients in the PK *** loosening and neovascularization were observed in 4 and 5 eyes in the PK group,*** graft immune rejection or elevation of intraocular pressure was observed in the two ***:For patients with elliptical-shaped corneas or corneal ulcers,FPK can avoid disrupting of corneal limbus,reduce the risk of postoperative complications,and can result in satisfactory visual quality.

关键词： fusiform penetrating keratoplasty multiple trephines infectious keratitis cornea

Tetrahedral framework nucleic acids/hyaluronic acidmethacrylic anhydride hybrid hydrogel with antimicrobial and anti-inflammatory properties for infected wound healing

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International Journal of Oral Science 2024年第3期16卷 436-447页

作者： Cai Qi Qiang Sun Dexuan xiao Mei Zhang Shaojingya gao Bin Guo Yunfeng lin State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases&West China Hospital of Stomatology Sichuan UniversityChengduChina Sichuan Provincial Engineering Research Center of Oral Biomaterials ChengduChina Department of Stomatology The First Medical CentreChinese PLA General HospitalBeijingChina

Bacterial resistance and excessive inflammation are common issues that hinder wound *** peptides(AMPs)offer a promising and versatile antibacterial option compared to traditional antibiotics,with additional anti-inflammatory ***,the applications of AMPs are limited by their antimicrobial effects and stability against bacterial *** are regarded as a promising drug delivery platform that could enhance the antibacterial properties and stability of ***,in this study,a composite hydrogel(HAMA/t-GL13K)was prepared via the photocross-linking method,in which tFNAs carry *** hydrogel was injectable,biocompatible,and could be instantly *** exhibited broad-spectrum antibacterial and anti-inflammatory properties by inhibiting the expression of inflammatory factors and scavenging ***,the hydrogel inhibited bacterial infection,shortened the wound healing time of skin defects in infected skin full-thickness defect wound models and reduced *** constructed HAMA/tFNA-AMPs hydrogels exhibit the potential for clinical use in treating microbial infections and promoting wound healing.

关键词： properties. hydrogel anhydride

维普期刊数据库

APFA:Ameliorated Pathfinder Algorithm for Engineering Applications

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Journal of Bionic Engineering 2024年第3期21卷 1592-1616页

作者： Keyu Zhong Fen xiao Xieping gao Key Laboratory of Computing and Stochastic Mathematics of Ministry of Education Hunan Normal UniversityChangsha410081China School of Mathematics and Statistics Hunan Normal UniversityChangsha410081China School of Computer Science Xiangtan UniversityXiangtan411105China Hunan Provincial Key Laboratory of Intelligent Computing and Language Information Processing Hunan Normal UniversityChangsha410081China

Pathfinder algorithm(PFA)is a swarm intelligent optimization algorithm inspired by the collective activity behavior of swarm animals,imitating the leader in the population to guide followers in finding the best food *** algorithm has the characteristics of a simple structure and high ***,PFA faces challenges such as insufficient population diversity and susceptibility to local optima due to its inability to effectively balance the exploration and exploitation *** paper proposes an Ameliorated Pathfinder Algorithm called APFA to solve complex engineering optimization ***,a guidance mechanism based on multiple elite individuals is presented to enhance the global search capability of the ***,to improve the exploration efficiency of the algorithm,the Logistic chaos mapping is introduced to help the algorithm find more high-quality potential solutions while avoiding the worst ***,a comprehensive following strategy is designed to avoid the algorithm falling into local optima and further improve the convergence *** three strategies achieve an effective balance between exploration and exploitation overall,thus improving the optimization performance of the *** performance evaluation,APFA is validated by the CEC2022 benchmark test set and five engineering optimization problems,and compared with the state-of-the-art metaheuristic *** numerical experimental results demonstrated the superiority of APFA.

关键词： Pathfinder algorithm Swarm intelligent Metaheuristic Engineering problems

An Efficient Multi-objective Approach Based on Golden Jackal Search for Dynamic Economic Emission Dispatch

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Journal of Bionic Engineering 2024年第3期21卷 1541-1566页

Dynamic Economic Emission Dispatch(DEED)aims to optimize control over fuel cost and pollution emission,two conflicting objectives,by scheduling the output power of various units at specific *** many methods well-performed on the DEED problem,most of them fail to achieve expected results in practice due to a lack of effective trade-off mechanisms between the convergence and diversity of non-dominated optimal dispatching *** address this issue,a new multi-objective solver called Multi-Objective Golden Jackal Optimization(MOGJO)algorithm is proposed to cope with the DEED *** proposed algorithm first stores non-dominated optimal solutions found so far into an ***,it chooses the best dispatching solution from the archive as the leader through a selection mechanism designed based on elite selection strategy and Euclidean distance index *** mechanism can guide the algorithm to search for better dispatching solutions in the direction of reducing fuel costs and pollutant ***,the basic golden jackal optimization algorithm has the drawback of insufficient search,which hinders its ability to effectively discover more Pareto *** this end,a non-linear control parameter based on the cosine function is introduced to enhance global exploration of the dispatching space,thus improving the efficiency of finding the optimal dispatching *** proposed MOGJO is evaluated on the latest CEC benchmark test functions,and its superiority over the state-of-the-art multi-objective optimizers is highlighted by performance ***,empirical results on 5-unit,10-unit,IEEE 30-bus,and 30-unit systems show that the MOGJO can provide competitive compromise scheduling solutions compared to published DEED ***,in the analysis of the Pareto dominance relationship and the Euclidean distance index,the optimal dispatching solutions provided by MOGJO are the closest to the ideal solutions for minimizing fuel costs

关键词： Dynamic economic emission dispatch Multi-objective optimization Golden jackal Euclidean distance index