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Body Mass Index and Hypertension Hemodynamic Subtypes in Yi Farmers and Migrants

Biomedical and Environmental Sciences 2012年第1期25卷 53-60页

作者： SHAN Guang Liang WEI Da Ying WANG chun xiu ZHANG Jian Hua WANG Bin MA Ming Ju PAN Li YU Tao XUE Fang WANG Ping WU Zheng Lai Department of Epidemiology and Statistics＇ Institute of Basic Medical Sciences Chinese Academy of Medical Sciences School of Basic Medicine Peking Union Medical College Beijing 100005 China Liangshan Yi Autonomous Prefectural Center for Disease Control and Prevention Xichang 615000 Sichuan China Department of Epidemiology and Social Medicine Xuanwu Hospital Capital University of Medical Sciences Beijing 100053 China

Objective To examine the relationship between overweight or obesity and the risk of the various hypertension hemodynamic subtypes in Yi farmers and migrants. Methods A cross-sectional study of 2 358 Yi farmers and 2 392 Yi migrants was carried out in the Liangshan Yi autonomous prefecture, Sichuan, China in 2007. Results The standardized prevalence of overweight in female Yi farmers （6.22%） was higher than in males （3.25%）, whereas in Yi migrants 32.56% of males and 28.78% of females were overweight. The standardized prevalence of obesity was 0 and 0.62% in male and female Yi farmers, compared to 3.91% and 5.57% in male and female Yi migrants, respectively. For both genders the standardized prevalence of ISH, IDH, and SDH was higher in Yi migrants than Yi farmers. Overweight and obese Yi men and women had a higher risk for IDH and SDH （P〈O.002） than non-overweight/obese individuals. However, an association of overweight or obesity with ISH was observed only in men. Conclusion Yi migrants have substantially higher proportion of overweight and obese individuals, as well as individuals affected by ISH, IDH, and SDH, than do Yi farmers. Overweight and obesity are significant risk factors for the development of hypertension in Yi people.

关键词： Body mass index (BMI) Overweight Obesity Hypertension Ethnic Yi Migrant China

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分散型可再生能源技术扩散中的收入效应研究

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系统工程理论与实践 2014年第2期34卷 530-537页

作者：张磊史春秀高伟中国矿业大学管理学院徐州221116

阻碍分散型可再生能源技术扩散的重要因素是其较高的采用成本,而随着居民收入水平的逐步增加,对这种新能源技术的采用行为也越来越普遍.基于元胞自动机技术,考虑到绝对收入水平和相对收入水平对居民采用行为的影响机制,将元胞划分为潜... 详细信息

阻碍分散型可再生能源技术扩散的重要因素是其较高的采用成本,而随着居民收入水平的逐步增加,对这种新能源技术的采用行为也越来越普遍.基于元胞自动机技术,考虑到绝对收入水平和相对收入水平对居民采用行为的影响机制,将元胞划分为潜在者、等待者和采用者三种状态并定义了相互间的转化概率,建立了收入影响下的分散型可再生能源技术扩散模型.通过与太阳能热水器扩散数据的对比证明了模型的合理性,仿真分析表明,相对收入系数与等待元胞转化概率成反比,与采用元胞转化概率成正比,潜在者相对收入系数变动的边际贡献小于等待者;此外,研究还发现采用示范效应和收入敏感度是在特定收入范围内而非收入最大值区域是最优的,初始采用元胞收入水平高低对扩散进程没有显著的促进作用.这些结论对可再生能源技术推广和企业市场营销决策都有着积极的借鉴意义.

关键词：分散型可再生能源技术扩散收入效应元胞自动机

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应用遗传算法拟合偏振X射线荧光重叠谱

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光谱学与光谱分析 2008年第3期28卷 704-706页

作者：罗立强詹秀春国家地质实验测试中心北京100037

X射线荧光光谱分析由于受能量探测器分辨率的限制,谱线重叠干扰严重。不采用合适的重叠谱峰分解或曲线拟合技术,很难进行成分定性和定量分析。样品中的元素及谱线未知、背景基线不确定和模型初始参数不准确是曲线拟合中的最大困难。有... 详细信息

X射线荧光光谱分析由于受能量探测器分辨率的限制,谱线重叠干扰严重。不采用合适的重叠谱峰分解或曲线拟合技术,很难进行成分定性和定量分析。样品中的元素及谱线未知、背景基线不确定和模型初始参数不准确是曲线拟合中的最大困难。有多种算法可应用于光谱分析中的曲线拟合。文章将遗传算法应用于永磁材料偏振X射线荧光中的重叠谱分解,研究了进化策略对谱峰分解质量的影响,比较了遗传算法与传统算法的拟合结果。研究表明遗传算法在谱线严重重叠情况下仍具有较强的谱峰分解能力;群体初始化和进化策略的正确选择是该算法成功应用的关键;遗传算法具有全局搜索能力,对重叠谱峰的分辨能力优于标准Marquardt-Levenberg算法。

关键词：遗传算法偏振X射线荧光重叠谱分解永磁材料

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Electrical properties of Copper(Ⅱ) phthalocyanine derivative thin films

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Optoelectronics Letters 2007年第1期3卷 43-46页

作者： WANG Ting-ting HE Zhi-qun ZHENG Xiao-pan WANG Yong-sheng ZHANG chun-xiu ZHANG Wen-guan Key Laboratory of Luminescence and Optical Information Ministry of Education Institute of Optoelectronic Technology Beijing Jiaotong University Beijing 100044 China Lab of Printing ＆ Packaging Material and Technology-Beijing Area Major Laboratory Beijing Institute of Graphic Communication Beijing 102600 China

This paper reports an investigation on the electrical properties of thin film devices made by Copper(II) phthalocyanine derivative and polycarbonate (PC) composite. The conducting and injection mechanism are further discussed. Materials of a variety composition were prepared into the thin film via spin-coating. ITO and aluminum were used as the bottom and top electrode respectively. J-V characteristic was measured and the result demonstrates that at a small bias region an Ohmic contact was achieved. As the forward bias increased, the current became space charge limited. The result of AC impedance measurement indicates the device could be equivalent to a parallel RC system. The introduction of PC into the CuPc possibly reduces the charge overlapping between the aromatic rings and led to a reduction in the molecular interaction. Hence, the ac conductivity decreases sharply as PC composition increases. But no change in the transport mechanism is found.

关键词：铜酞菁染料衍生物聚碳酸酯复合薄膜电学性质

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基于混沌算子网络的时间序列多步预测研究

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物理学报 2010年第11期59卷 7650-7656页

作者：修春波徐勐天津工业大学电气工程与自动化学院天津300160

结合相空间重构理论和时间序列分析理论,提出一种用于时间序列多步预测的网络模型.网络采用多个混沌算子加权求和的形式构成.网络各层单元采用固定权值连接,混沌算子的控制参数利用混沌优化算法进行训练调节,从而控制预测网络的动力学行... 详细信息

结合相空间重构理论和时间序列分析理论,提出一种用于时间序列多步预测的网络模型.网络采用多个混沌算子加权求和的形式构成.网络各层单元采用固定权值连接,混沌算子的控制参数利用混沌优化算法进行训练调节,从而控制预测网络的动力学行为.利用已知时间序列数据构造出训练样本,训练样本在网络训练过程中仅使用一次,促使网络的动力学特性随时间的推移而变化,并逐渐逼近被预测系统的动力学特性,最终完成对未来时刻数据的预测.在对理论数据进行预测分析时,通过计算预测序列的Lyapunov指数验证了预测网络的有效性.在对实际时间序列的预测过程中,该网络表现出了良好的预测性能.仿真结果表明,该预测网络可对多种时间序列在一定的预测步长范围内实现有效的预测.

关键词：混沌算子预测网络多步预测时间序列

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混合动力电动汽车的跟车控制与能量管理

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自动化学报 2022年第1期48卷 162-170页

作者：赵秀春郭戈大连理工大学大连116024 大连民族大学大连116600 东北大学流程工业综合自动化国家重点实验室沈阳110004 东北大学秦皇岛分校控制工程学院秦皇岛066004

混合动力电动汽车(Hybrid electric vehicles,HEVs)的能量管理问题至关重要,而混合动力电动汽车的跟车控制不仅涉及跟车效果与安全性,也影响着能量的高效利用.将HEVs的跟车控制与能量管理相结合,提出一种基于安全距离的HEVs车辆跟踪与... 详细信息

混合动力电动汽车(Hybrid electric vehicles,HEVs)的能量管理问题至关重要,而混合动力电动汽车的跟车控制不仅涉及跟车效果与安全性,也影响着能量的高效利用.将HEVs的跟车控制与能量管理相结合,提出一种基于安全距离的HEVs车辆跟踪与能量管理控制方法.首先,考虑坡度、载荷变动建立了HEVs车辆跟车系统的非线性模型,并基于安全距离,提出一种基于道路观测器的动态面控制(Dynamic surface control,DSC)进行车辆跟踪控制.然后,结合跟踪控制下工况循环,采用滚动动态规划(Dynamic programming,DP)算法进行混合动力电动汽车能量实时优化控制.最后,通过仿真研究进行验证.

关键词：混合动力电动汽车动态面控制车辆跟踪能量管理动态规划

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Serum 25-Hydroxyvitamin D Level Might Be a Useful Indicator of Disease Severity in Obese Children With Atopic Dermatitis:A Case-Control Study

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International Journal of Dermatology and Venereology 2024年第1期7卷 6-11页

作者： Jing-Jing Chen Xiao-Kai Fang xiu-Mei Liu Xiao-chun Liu Xu Yao Department of Allergy and Rheumatology Hospital for Skin Diseases(Institute of Dermatology)Chinese Academy of Medical Sciences and Peking Union Medical CollegeNanjingJiangsu 210042China

Objective:To assess the relationship between the severity of atopic dermatitis(AD)in children of varying weight categories and their serum 25-hydroxyvitamin D[25(OH)D]***:The study population comprised 899 patients with AD and 854 age-and sex-matched *** Mann-Whitney U test and Kruskal-Wallis H tests were used to assess differences between groups,and Spearman correlation analysis was used to test ***:The 25(OH)D level in the AD group was M(Q_(25),Q_(75)),24.0(19.7,28.4)ng/mL,which was significantly lower than the control group(26.4[23.6,29.9]ng/mL;Z=-3.34,P=0.001).25(OH)D levels in children with AD were negatively correlated with body mass index(r=-0.30,P<0.001),Severity scoring of Atopic Dermatitis(SCORAD;r=-0.14,P<0.001),total immunoglobulin E(r=-0.13,P<0.001),and eosinophil(r=-0.08,P=0.017).There were statistically significant differences in 25(OH)D(H=18.46,P<0.001),total immunoglobulin E(H=9.13,P=0.010),eosinophil(H=67.17,P<0.001),and SCORAD(H=10.49,P=0.005)among groups with different body mass index *** 25(OH)D levels were 22.3(17.5,27.1)ng/mL in the overweight AD group and 22.3(17.6,25.7)ng/mL in the obese AD group,which were significantly lower than those in the normal-weight AD group(24.7[20.4,25.5]ng/mL;P=0.003,P=0.004).25(OH)D levels were negatively correlated with SCORAD in obese AD patients(r=-0.25,P=0.010).Conclusion:Vitamin D insufficient or deficient is obvious in children AD *** 25(OH)D levels in the overweight/obese AD group are significantly lower than those in the normal-weight AD *** D level is negatively correlated with SCORAD in obese children with AD.

关键词： atopic dermatitis vitamin D disease severity index immunoglobulin E body mass index eosinophil children overweight/obese

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Production of Transgenic Tall Fescue Plants with Enhanced Stress Tolerances by Agrobacterium tumefaciens-Mediated Transformation

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Agricultural Sciences in China 2006年第5期5卷 330-338页

作者： WU Guan-ting CHEN Jin-qing HU Zhang-hua LANG chun-xiu CHEN Xiao-yun WANG Fu-lin JIN Wei XIA Ying-wu Institute of Virology and Biotechnology Zhejiang Academy of Agricultural Sciences Hangzhou 310021 P.R. China Institute of Nuclear-Agricultural Sciences Zhejiang University Hangzhou 310029 P.R. China

In order to improve stress tolerances of turf-type tall fescue （Festuca arundinacea Schreb.）, Agrobacterium tumefaciens strain EHA105 carrying plasmid pCMD containing stress tolerance-related CBF1 gene from Arabidopsis thaliana was used to transform mature seeds-derived embryogenic calli of four cultivars. A total of 112 transgenic plants were regenerated from 32 independent lines and verified by histochemical detection of GUS activity, PCR assay and Southern hybridization analysis. The transformation frequency ranged from 0.92 to 2.87% with apparent differences among the cultivars. Stress tolerances of transgenic plants were enhanced, which was shown by the facts that transgenic plants had distinct growth superiority and significantly higher survival rate than non-transformed ones under high salinity and high osmosis stresses, and that relative electronic conductivity of in vitro leaves treated with low and high temoeratures, dehvdration and high salinity stresses was 25-30% lower in transgenic plants than in control *** addition,it was observed that growth of transgenic plants was inhibited due to constitutive overexpression of CBF1 gene under normal environmental conditions.

关键词： tall fescue (Festuca arundinacea Schreb.) Agrobacterium tumefaciens genetic transformation CBF1 gene stress tolerance

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