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The Association Between Daily Physical Activity and Risk of Hypertension in Middle-Aged and Older Adults:A Nationwide Cohort Study in China
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作者 Junhua Zhang jie rong +1 位作者 Hui Zhang Yongmei Yan 《Journal of Clinical and Nursing Research》 2024年第9期83-92,共10页
Physical activity (PA) plays a key role in the treatment of hypertension, and moderate to vigorous PA has been documented to lower the risk of developing hypertension. However, dose-response relationships between PA a... Physical activity (PA) plays a key role in the treatment of hypertension, and moderate to vigorous PA has been documented to lower the risk of developing hypertension. However, dose-response relationships between PA and hypertension are not consistent, and little is known about this relationship within the Chinese middle-aged and older people. We investigated the relationship between PA and hypertension within this population using China Health and Nutrition Survey 1991-2015 data. Physical activity was expressed in terms of the metabolic equivalent task (MET) and participants were divided into groups according to quartiles, namely, Q1 (< 32.97 METs-h/w), Q2 (32.97-60.38 METs-h/ w), Q3 (60.38-98.95 METs-h/w), and Q4 (> 98.95 METs-h/w). Compared with the Q1 group, the odds ratio of risk with hypertension (95% CIs) after adjusting for confounding factors were 0.63 (0.35, 1.12), 0.49 (0.28, 0.86), and 0.62 (0.35, 1.09) for those in Q2, Q3, and Q4, respectively. Restricted cubic spline functions were used and a U-shaped relationship between physical activity and hypertension risk was found, indicative of an optimal level of physical activity, which was found to be 112 METs-h/w. Our data suggest maintenance of optimal levels of total daily physical activity may be important for preventing hypertension in Chinese adults over the age of 40. 展开更多
关键词 Physical activity HYPERTENSION Middle age Older adults
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高阶有限差分法求解Helmholtz方程
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作者 陈健军 揭蓉 +1 位作者 朱小玲 隆广庆 《南宁师范大学学报(自然科学版)》 2020年第1期1-7,17,共8页
提出加权六阶有限差分方案对Helmholtz方程求解.采用中心六阶差分方案离散二阶导数项,匹配界面和边界(MIB)方法用于处理由此产生的边界问题.对于零阶项的离散化,通过利用所有13个点设计加权平均法,并通过最小化数值频散来确定权重参数.... 提出加权六阶有限差分方案对Helmholtz方程求解.采用中心六阶差分方案离散二阶导数项,匹配界面和边界(MIB)方法用于处理由此产生的边界问题.对于零阶项的离散化,通过利用所有13个点设计加权平均法,并通过最小化数值频散来确定权重参数.该新方案在抑制数值频散方面简单有效.最后,通过数值算例说明了新方案的数值收敛性和有效性. 展开更多
关键词 HELMHOLTZ方程 有限差分法 数值频散 匹配界面和边界(MIB)方法
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Steklov特征值问题的快速Fourier-Galerkin方法
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作者 揭蓉 陈健军 +1 位作者 朱小玲 隆广庆 《南宁师范大学学报(自然科学版)》 2020年第1期8-17,共10页
该文将Steklov特征值问题化为边界积分方程特征值问题,利用Fourier基底给出边界积分方程特征值问题的Fourier-Galerkin方法和具有光滑核的紧积分算子的稠密矩阵的压缩策略,并证明该方法收敛阶达到最佳.
关键词 Steklov特征值问题 边界积分特征值方程 Fourier-Galerkin方法
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弱奇异积分算子特征值问题的无网格配置法
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作者 宣丽凤 陈健军 +1 位作者 揭蓉 隆广庆 《广西师范学院学报(自然科学版)》 2018年第3期20-26,共7页
该文讨论奇异积分算子特征值的无网格算法.首先介绍了移动最小二乘法逼近(MLS)方法,然后介绍特征值问题的基础知识,最后,结合最小二乘逼近的方法和求解特征值的理论知识,给出求解特征值问题的两种算法形式,并对算法求得的特征值进行收... 该文讨论奇异积分算子特征值的无网格算法.首先介绍了移动最小二乘法逼近(MLS)方法,然后介绍特征值问题的基础知识,最后,结合最小二乘逼近的方法和求解特征值的理论知识,给出求解特征值问题的两种算法形式,并对算法求得的特征值进行收敛性分析. 展开更多
关键词 特征值问题 MLS方法 无网格配置法
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