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关键词： 饮食偏好   骨关节炎   欧洲人群   孟德尔随机化   全基因组关联研究   因果关系  

摘要： 背景:有研究表明饮食摄入与骨关节炎之间存在潜在的关联,但食物偏好与骨关节炎间是否存在因果关系仍未可知。国内目前尚未有大规模饮食偏好与骨关节炎全基因组关联研究。目的:探究欧洲人群饮食偏好与骨关节炎间的因果关联,以期为骨关节炎的预防提供理论依据,同时为国内髋膝关节骨关节炎高危人群识别提供参考数据。方法:选用人类全基因组关联研究数据中欧洲人群20种饮食偏好遗传统计数据集筛选暴露因素相关工具变量,结局选用骨关节炎遗传统计数据集,排除与混杂因素相关工具变量后,主要采用逆方差加权分析法进行两样本孟德尔随机化因果关联分析,其余4种统计方法作为补充,并对结果进行敏感性检验。结果与结论:①逆方差加权分析结果显示,喜好烤肉(OR=1.204,95%CI:1.058-1.370,P=0.005)、牛肉(OR=1.167,95%CI:1.034-1.317,P=0.012)、鸡肉(OR=1.399,95%CI:1.119-1.749,P=0.003)、猪排(OR=1.218,95%CI:1.039-1.427,P=0.015)及咖啡(OR=1.133,95%CI:1.037-1.238,P=0.006)是膝髋关节骨关节炎的风险因素;喜好蔬菜(OR=0.893,95%CI:0.827-0.964,P=0.004)和醋(OR=0.897,95%CI:0.812-0.991,P=0.032)是膝髋关节骨关节炎的保护因素;②敏感性分析结果显示,纳入分析的工具变量不存在水平多效性及偏倚,并根据异质性分析结果使用对应的逆方差加权分析效应模型;③此次研究结果在饮食偏好与髋膝关节骨关节炎相关研究中提供了一定的参考价值,但仅纳入来自欧洲人群的人类全基因组关联研究数据,研究结果在其他种族中的有效性仍待检验;且并未进行性别、年龄及其他健康状态分层,研究结果难以完全排除来自人群分层的偏倚,未来仍需更大规模、更细化分类的样本数据开展相关因果关系研究。

关键词： Volumetric locking   Mixed displacement-pressure formulation   EFG method   Irregular pressure node distribution   Hyperelastic materials  

摘要： Rubber-like materials that are commonly used in structural applications are modelled using hyperelastic material models. Most of the hyperelastic materials are nearly incompressible, which poses challenges, i.e., volumetric locking during numerical modelling. There exist many formulations in the context of the finite element method, among which the mixed displacement-pressure formulation is robust. However, such a displacement-pressure formulation is less explored in meshfree methods, which mitigates the problem associated with mesh distortion during large deformation. This work addresses this issue of alleviating volumetric locking in the element-free Galerkin method (EFGM), which is one of the popular meshfree methods. A two-field mixed variational formulation using the perturbed Lagrangian approach within the EFGM framework is proposed for modelling nearly incompressible hyperelastic material models, such as Neo-Hookean and Mooney-Rivlin. Taking advantage of the meshless nature of the EFGM, this work introduces a unique approach by randomly distributing pressure nodes across the geometry, following specific guidelines. A wide spectrum of problems involving bending, tension, compression, and contact is solved using two approaches of the proposed displacement-pressure node formulation involving regular and irregular pressure node distribution. It is observed that both approaches give accurate results compared to the reference results, though the latter offers flexibility in the pressure nodal distribution. (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic). (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic) (sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic). (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)-(sic)(sic)(sic)(sic)(sic)(si

关键词： Micropolar elasticity   Sliding friction   Size effect   Indentation   Singular integral equation  

摘要： In this study, the sliding friction contact problems associated with the indentation of an elastic half-plane by rigid cylindrical and flat punches were investigated within the context of the micropolar theory. The micropolar theory of elasticity introduces the characteristic material length and the dimensionless coupling number to describe the size effect. Coulomb's friction law is satisfied by a punch when it is subjected to both normal and tangential forces. Using the Fourier integral transformation technique, these mixed-boundary value problems were reduced to singular integral equations of the second kind in which the unknown quantity is the contact stress on the contact surface. The collocation method was utilized to solve the integral equations numerically. An extensive parametric study was conducted to investigate the effects of the friction coefficient, the characteristic material length, and the dimensionless coupling number on the normal and in-plane stresses. The results show that the contact stress predicted by the micropolar theory differs significantly from those predicted by the couple stress theory and the classical elasticity theory.

关键词： Boussinesq problem   Finite elastic layer   Surface effect   Thickness effect   Analytical solution  

摘要： Both the thickness effect and surface effect should be important in nano-indentation behavior of coatings due to the finite thickness and small indentation size. As a basic solution, the two-dimensional Boussinesq problem of a finite elastic layer bonded to a rigid substrate is studied in this paper, employing the surface-energy-density-based elastic theory. The Airy stress function and Fourier integral transform methods are adopted to solve the problem. A nalytical solutions of both the stress and displacement fields are well achieved for a finite elastic layer under a concentrated force and a uniform pressure. Unlike the classical solutions, it is discovered that both the thickness effect and surface effect will show significant influences on the Boussinesq elastic behaviors. The surface effect would harden the finite elastic layer and induce a more uniformly distributing displacements and stresses. Only when the thickness is sufficiently large, the Boussinesq solution of an elastic half space may represent that of a finite elastic layer case. A generalized hardness is further defined to include the coupling effects of thickness and surface for the Boussinesq problem of a finite elastic layer. Such a study would assist in the design and property evaluation of coatings and micro-devices with layer-substrate structures.

关键词： 乡村振兴战略   老年人需求   农村社区   老年教育课程  

摘要： 乡村振兴战略的提出,不单推动农村经济发展,同时也对农村社会治理提出更高要求.在老龄化逐步加深的背景下,农村社区内老年人的教育需求日益凸显.农村老年教育既是提高个人素质的途径,也是增强乡村社区凝聚力,提升文化软实力的有效手段.从课程设计原则、课程在乡村振兴中的作用等角度,探讨符合老年人生理与心理特点的教育课程,并结合具体实践,提出有针对性的开发策略,旨在为农村社区提供可持续发展的教育支持.

关键词： 中职数学   专业发展   课程思政  

摘要： 数学作为中职核心课程,不仅富有独特的学科价值,还承载着“立德树人”的重要使命。本文主要探索如何结合中职专业发展的需求在数学教学中落实课程思政,首先分析了中职数学课程思政的实施现状,然后采用文献研究法,明确了中职数学课程思政的实施策略,最后结合不同专业给出了数学课程思政的案例。

关键词： 公安本科院校   公安学   公安人才   警察学院   一所   海警   职业院校   人才培养模式  

摘要： 2021年,海南省委、省政府通过有效整合海南政法职业学院(以下简称“海政”)等相关资源筹建海南警察学院(以下简称“海警院”)。海政是一所专业设置涵盖公安、司法、法律类专业的公办高等政法类职业院校。海警院拟办成一所专业涵盖法学、公安学、公安技术的省属公办公安本科院校,这与原来海政人才培养模式有较大不同。因此,对海警院公安人才培养模式进行研究,不仅能促进海政教师顺利转型,也能为培养自贸港所需的公安人才奠定扎实的师资基础。

关键词： 心理弹性发展模型   经皮肾镜取石术   肾结石   不良情绪   饮水依从性  

摘要： 目的:分析基于心理弹性发展模型下的护理模式在经皮肾镜取石术治疗肾结石中的临床应用效果。方法:回顾性选取南阳市第一人民医院2022年9月至2023年9月收治的84例经皮肾镜取石术治疗肾结石患者,按护理方法不同分为心理弹性组(n=42)、对照组(n=42),对照组行常规护理,心理弹性组在此基础上给予心理弹性发展模型下的护理模式。比较两组术后恢复情况、并发症发生率、心理弹性[Wagnild-Young心理弹性量表(RS-11)]、饮水依从性、护理满意度。结果:心理弹性组拔除造瘘管、拔除导尿管、下床活动、住院时间均短于对照组(P<0.05);两组并发症发生率比较,差异无统计学意义(P>0.05);干预后心理弹性组RS-11评分高于对照组(P<0.05);干预后心理弹性组饮水依从性高于对照组(P<0.05);心理弹性组护理满意度97.62%高于对照组80.95%(P<0.05)。结论:对经皮肾镜取石术治疗肾结石患者实施基于心理弹性发展模型下的护理模式,能改善术后恢复情况,提高心理弹性、饮水依从性、护理满意度。

关键词： 人力资源管理   员工考核   绩效考核   人才储备   人力资源配置   三甲医院   信息化系统   医院人才  

摘要： 随着医疗行业的快速发展,尤其是三甲医院对人才的需求越来越高,人力资源管理已成为医院运营的核心组成部分。然而,传统的管理模式无法有效支撑医院的长远发展,需构建信息化平台提升医院管理效能、促进员工发展。三甲医院人力资源管理的核心需求战略需求与功能痛点整合。医院在人力资源配置上不仅需满足日常运作,还必须助力医疗机构长期的发展。因此医院战略规划中包含发展及人才队伍构建计划,这就需要建立人力资源信息化平台,为医院人才的整体规划、用人需求、人才储备等方面提供有力支撑。目前,部门间数据互通不畅、员工考核结果的主观性偏高等各种因素对管理的效能和决策的合理性产生影响,信息化系统可以有效解决这些问题,并增强数据互通、流程协作及绩效考核的科学化水平。

关键词： 地球系统模式   发展历程   研究进展   不足与挑战   陆-海-气-人耦合  

摘要： 地球系统模式是理解和预测全球变化的核心工具,近年来取得了显著进展。其性能提升体现在圈层耦合过程的精细化发展,以及圈层内复杂物理和化学过程的逐步引入。不确定性的降低则得益于新方法和新技术的发展和应用。然而,地球系统模式仍面临诸多挑战,包括对复杂交互过程的表征能力不足、社会-生态系统过程模拟的局限性,以及区域极端事件模拟能力的提升需求。未来的发展需深化跨学科协作,借助新技术强化数据获取与模型预测能力,同时聚焦社会-生态系统过程及其影响机制的研究,以增强对区域极端事件的模拟与预测能力,构建完善的陆-海-气-人相互耦合的新一代地球系统模式,为人类社会的可持续发展及全球变化的应对和预测提供更科学的支撑。