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中国中老年人群甘油三酯葡萄糖指数-腰围身高比与认知障碍关联的队列研究

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中华流行病学杂志 2024年第6期45卷 802-808页

作者：侯丁淳魏玥孙玉梅裴丽君陈功北京大学人口研究所北京100871 北京大学护理学院北京100191 北京大学中国老龄事业发展研究中心北京100871

目的分析中老年人中甘油三酯葡萄糖指数(TyG)-腰围身高比(WHtR)(TyG-WHtR)与认知障碍的关联。方法应用中国健康与养老追踪调查数据,以2011年和2015年的8946名中老年人为基线人群,构建队列数据库。应用Cox比例风险回归模型估计中老年人基... 详细信息

目的分析中老年人中甘油三酯葡萄糖指数(TyG)-腰围身高比(WHtR)(TyG-WHtR)与认知障碍的关联。方法应用中国健康与养老追踪调查数据,以2011年和2015年的8946名中老年人为基线人群,构建队列数据库。应用Cox比例风险回归模型估计中老年人基线TyG-WHtR不同水平与认知障碍风险的关联,并分别进行年龄和性别分层分析。结果8946名研究对象平均随访7.08人年,认知障碍发病密度为21.15/1000人年。与TyG-WHtR的Q_(1)水平相比,其Q_(3)和Q_(4)水平分别使认知障碍风险增加32%(HR=1.32,95%CI:1.09~1.60)和47%(HR=1.47,95%CI:1.14~1.91)。趋势检验显示,认知障碍风险随TyG-WHtR水平升高而增加,且存在剂量-反应关系(P=0.001)。分层分析显示,45~59岁人群中,与TyG-WHtR的Q_(1)水平相比,其Q_(3)水平使认知障碍风险增加34%(HR=1.34,95%CI:1.02~1.78);≥60岁人群中,相比于TyG-WHtR的Q_(1)水平,其Q_(3)和Q_(4)水平分别使认知障碍风险增加31%(HR=1.31,95%CI:1.01~1.72)和63%(HR=1.63,95%CI:1.15~2.31);男性中,TyG-WHtR水平与认知障碍风险无统计学关联(P>0.05);女性中,相比于TyG-WHtR的Q_(1)水平,其Q_(4)水平使认知障碍风险增加76%(HR=1.76,95%CI:1.26~2.46)。结论中老年人中较高的TyG-WHtR水平可增加认知障碍风险,且存在年龄、性别差异,早期的心血管健康管理和科学合理的体重管理对预防认知障碍具有重要意义。

关键词：认知障碍甘油三酯葡萄糖指数-腰围身高比队列研究中老年人

1982—2021年中国60~94岁老年人痴呆症死亡趋势的年龄-时期-队列分析

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中华预防医学杂志 2024年第8期58卷 1177-1183页

作者：魏玥梁博李佳佳闫晓晋裴丽君北京大学人口研究所北京100871 北京大学中国人口健康与发展研究中心北京100871

目的分析1982—2021年中国60~94岁老年人痴呆症死亡率的趋势。方法采用2021年全球疾病负担数据库数据,利用Joinpoint回归模型分析1982—2021年中国60~94岁老年人痴呆症死亡率的变化趋势;采用年龄-时期-队列分析方法,对中国60~94岁老年... 详细信息

目的分析1982—2021年中国60~94岁老年人痴呆症死亡率的趋势。方法采用2021年全球疾病负担数据库数据,利用Joinpoint回归模型分析1982—2021年中国60~94岁老年人痴呆症死亡率的变化趋势;采用年龄-时期-队列分析方法,对中国60~94岁老年人痴呆症死亡数据的年龄效应、时期效应和队列效应进行分解。结果1982—2021年,中国60~94岁老年女性痴呆症的粗死亡率(133.67/10万~214.02/10万)高于男性(70.92/10万~119.70/10万),女性痴呆症年龄标准化死亡率(230.74/10万~246.87/10万)也高于男性(132.88/10万~140.19/10万),且两性痴呆症的年龄标准化死亡率均呈"N"型波动趋势。60~94岁老年男性痴呆症死亡率平均年度变化百分比(AAPC)为0.07%(95%CI:0.01%~0.13%),老年女性痴呆症死亡率的AAPC为-0.01%(95%CI:-0.08%~0.07%)。年龄效应分析显示,自60岁起,男性和女性痴呆症死亡风险随增龄而增长,特别是在75~94岁老年人中,痴呆症死亡率迅速上升;时期效应分析显示,60~94岁老年男性和女性痴呆症死亡风险总体呈现下降趋势,但在2017—2021年有所上升;队列效应分析显示,较晚出生队列的痴呆症死亡风险更低。结论1982—2021年,中国60~94岁老年人痴呆症死亡率波动变化,但近年来痴呆症死亡率反弹式上升,未来应重点关注女性和75~94岁人群。

关键词：死亡率痴呆症年龄-时期-队列分析中国监测

Sufficient conditions of the various stabilities of the linear time-varying delayed differential equations

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Theoretical & Applied Mechanics Letters 2013年第6期3卷 59-61页

作者： lijun pei School of Mathematics and Statistics Zhengzhou University

Due to the appearance and the study of the ornithopter and flexible-wing micro air vehicles, etc., the time-varying systems become more and more important and ubiquitous in the study of the mechanics. In this letter, the sufficient conditions of the uniform asymptotic stability are first presented for the delayed time-varying linear differential equations with any time delay by employing the Dini derivative, Lozinskii measure and the generalized scalar Halanay delayed differential inequality. They are especially based on the estimation of the arbitrary solutions but not the fundamental solution matrix since their solutions＇ space is infinite-dimensional. Then some sufficient conditions of the stability, asymptotic stability and uniform asymptotic stability of the delayed time-varying linear system with a sufficiently small time delay are reported by employing Taylor expansion and Dini derivative. It implies that these stabilities can be guaranteed by the Lozinskii measure of the matrix composing of the time delay and the coefficient matrices of the system.

关键词： sufficient conditions stability uniform asymptotic stability time delay time-varying linearsystem

Adverse Childhood Experiences and Depressive Symptoms Trajectories Among Middle-Aged and Elderly—China,2011–2018

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China CDC weekly 2022年第27期4卷 588-592,I0003-I0007页

作者： Jiajia Li Shiqi Lin lijun pei Institute of Population Research/China Center on Population Health and Development Peking UniversityBeijingChina.

Summary What is already known about this topic?Previous studies in western populations have found consistent relationships between adverse childhood experiences and the development of mood and anxiety disorders,especially depressive symptoms in adolescence and *** is added by this report?This study used a longitudinal design and analytic method to model depressive symptom trajectories from 2011 to 2018 among the middle-aged and elderly in *** study also investigated the association between adverse childhood experiences and adulthood depressive symptoms in the Chinese *** are the implications for public health practice?Future public policy could consider early prevention and intervention on adverse childhood experiences to prevent adult depressive ***,it is essential to create safe,stable,and nurturing environments for children’s development.

关键词： prevention Middle policy

Trends of Adverse Pregnancy Outcomes in a High Prevalence Region of Birth Defects——Shanxi Province,China,2007-2019

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China CDC weekly 2021年第31期3卷 661-664页

作者： Shiqi Lin Yuan Zhang Jiajia Li Jilei Wu lijun pei Institute of Population Research/China Center on Population Health and Development Peking UniversityBeijingChina National Research Institute for Health and Family Planning BeijingChina

Summary What is already known about this topic?Shanxi Province in northern China has been identified as a region with the highest prevalence of birth defects *** large amounts of financial support devoted for prevention and related interventions for birth defects,huge progress has been made as a 60% decrease in its prevalence was observed from 2009 to 2014.

关键词： nationwide devoted prevention

Measuring the Effect of COVID-19 Pandemic on Mortality:Review and Prospect--China,2021

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China CDC weekly 2022年第23期4卷 499-503页

作者： Jinlong Lin Guogui Huang Yue Wei lijun pei Institute of Population Research China Center on Population Health and DevelopmentPeking UniversityBeijingChina Macquarie Business School Macquarie UniversitySydneyAustralia

Current progress in measuring the effect of the pandemic on mortality is *** studies have comprehensively and systematically elucidated the mechanism through which the pandemic affects mortality and what indicators are valid to capture such an *** paper presents a comprehensive analysis regarding the multifaceted effects of coronavirus disease 2019(COVID-19)on mortality and its measurements[i.e.,confirmed deaths per million people(CDPMP),case fatality rate(CFR),infection fatality risk(IFR),excess mortality P-score(EMPS),and life expectancy(LE)].It was revealed that both data collection efforts and measurements on mortality due to COVID-19 were far from perfect and discussed the importance of accurate,prompt,and accessible data by any government over the course of fighting against the COVID-19 *** is believed that the biggest challenge in measuring the effect of the COVID-19 pandemic on mortality lies not in the construction of indicators at the academic level,but in the collection of data at the practical ***,it is suggested to take measures to better monitor the development of the pandemic and mitigate the increasing burdens borne by the public health systems by improving the tracking system of mortality,standardizing the diagnosis of COVID-19’s deaths,and disclosing mortality data.

关键词： diagnosis prompt fighting

Trends in the Prevalence of Cognitive Impairment Among Older Adults Aged 65 to 105 Years—China,2002–2018

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China CDC weekly 2022年第42期4卷 945-949页

作者： Xiaojin Yan Shiqi Lin Jiajia Li Hao Cheng Xiangguo Liu lijun pei Institute of Population Research Peking UniversityBeijingChina National Academy of Innovation Strategy China Association for Science and TechnologyBeijingChina

Introduction:This study aims to analyze trends and subgroup differences in the prevalence of cognitive impairment among older Chinese adults aged 65–105 years from 2002 to ***:Data were drawn from six waves of the Chinese Longitudinal Healthy Longevity Survey(CLHLS).Cognitive function was measured using the Chinese version of the Mini-Mental State Examination(CMMSE).Cognitive impairment was determined by the total CMMSE score and educational attainment of *** generalized estimating equation(GEE)models with a logistic link and binominal distribution were performed to assess the secular trend in the ***:The prevalence of cognitive impairment among older adults aged 65–105 years decreased from 3.44%[95%confidence interval(CI):3.15%–3.73%]in 2002 to 2.41%(95%CI:2.17%–2.65%)in 2018 in *** prevalence was slightly higher in women than in men in 2002(3.71%vs.3.13%,P<0.05),and there was no significant difference between women and men in 2018(2.60%vs.2.21%,P=0.12).Rural older adults had a higher prevalence of cognitive impairment before 2014,but their urban counterparts had a higher prevalence in 2018(2.75%vs.2.06%,P<0.05).The GEE regression model showed that each successive year was associated with a 3%reduction in the odds of the prevalence of cognitive impairment[odds ratio(OR)=0.97;95%CI:0.97–0.97;P<0.05].Conclusions:The prevalence of cognitive impairment among Chinese older adults aged 65–105 years declined slowly from 2002 to *** gender,urban-rural,age,and regional differences in the prevalence of cognitive impairment changed over time.

关键词： slowly nominal successive

Sufficient,necessary and iD conditions of the stability of the coefficients-time-varying linear system with time delays

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Sufficient,necessary and iD conditions of the stability of t...

基于迁移学习的LLaMA 2大语言模型微调优化方法

第九届全国动力学与控制学术会议

作者： pei lijun Department of Mathematics Zhengzhou University

Due to the appearance and the study of the various kinds of the time-varying mechanisms(such as the ornithopter,flexible-wing micro air vehicles,space shuttles, missiles,etc.),the time-varying systems become more and more important and ubiquitous in the study of the *** they should be viewed as a brand-new differential equations systems and the different methods be employed to study them.

关键词： sufficient necessary and iD conditions stability uniform asymptotic stability time delay time-varying linear system

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软件工程 2024年第9期27卷 32-36页

作者：孙倩石竞泽裴丽君张倩怡徐凤强大连东软信息学院辽宁大连116023 大连交通大学软件学院辽宁大连116028

在计算资源受限情况下,针对大语言模型微调面临的训练成本高、微调时间长等问题,提出一种基于迁移学习的预训练大模型的微调优化方法。首先,在原有自注意力验证损失函数中引入权重方向惩罚因子,提高模型收敛速度。其次,改进自注意力验... 详细信息

在计算资源受限情况下,针对大语言模型微调面临的训练成本高、微调时间长等问题,提出一种基于迁移学习的预训练大模型的微调优化方法。首先,在原有自注意力验证损失函数中引入权重方向惩罚因子,提高模型收敛速度。其次,改进自注意力验证优化器,用来平衡不同权重参数的衰减程度。实验结果表明,改进后的微调优化方法可以有效减少微调的迭代次数,提高微调效率,从而提升大语言模型在下游任务的迁移应用能力。

关键词：大语言模型微调优化迁移学习

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