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Plasma ghrelin in response to submaximal exercise in college studetns of different training status

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Plasma ghrelin in response to submaximal exercise in college...

角色的扭曲:西部地区产业结构演进的历史回顾

中国生理学会第23届全国会员代表大会暨生理学学术大会

作者： Yun-Hong WANG~1,Yuan YAO~1,Lei LIANG~1,Men-Hua ZHAO~1,Xiao-Ran LIU~1,Chao-Shu TANG~2 1 Capital Institute Of Physical Education,beijing,100088,China 2 beijing university,beijing 100871,China

Introduction:Ghrelin is an orexigenic hormone secreted from endocrine cells in the stomach and other *** previous studies have investigated the response of plasma total ghrelin to exercise,and most of these studies indicated plasma total ghrelin concentrations were unaffected by a single session of exercise,or were suppressed for up to an hour after the cessation of ***,no studies have documented the level of ghrelin more than 3 h after exercise *** study was to investigate plasma levels in response to acute exercise of different training status in order to understand the role of ghrelin in exercise ***:Twenty eight healthy male college students of martial arts(n=17) and other college students(n=16),(aged 21.5±1.1 vs 19.1±0.5,unit:year;body mass 69.8+11.8 vs 66.4±9.7,unit:kg;height 173.2±6.2 vs 175.0±7.6,unit:cm;BMI 23.2±3.3 vs 21.8±3.7,unit:kg/m;VO2max 43.7±5.9 vs 41.1±10.0,unit:mL/(min·kg);training status:6.5±3.1 vs 0.0±0.0,unit:year),participated in this *** former students practiced martial arts regularly for 3-10 years;the latter students didn’t participate in regular exercise *** experiment included a maximal incremental exercise test and a submaximal exercise with one week in *** maximal incremental exercise tests were performed on the *** the test,more than 10 min resting period was allowed to evaluate the parameters at rest,as well as to withdraw the blood *** maximal exercise test started at a power output of 50 W which was increased 30 W every 3 min until *** sub-maximal incremental exercise was performed using the same *** 5 min warming up,the subjects maintained the intensity of 60%-70% VO2max for 25 min,followed by a 5 min of cool *** pedaling rates of both trials were 60 rev/*** pressure(BP) as well as heart rate(HR) was measured at 0,1,3 and 5 h after the exercise *** blood sample was collected at the same ***

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唐都学刊 2004年第6期20卷 95-98页

作者：刘静罗佐宪中国人民大学国际关系学院北京100872 中国石油化工集团总公司战略规划研究所北京100083

西部地区作为一个重要区域,其产业结构的优化,不仅是西部地区各方面(经济、社会、资源与环境)协调发展的前提条件,更是全国产业结构优化的有机组成部分,是促进整个国民经济协调发展、各民族共同繁荣进步的重要保证。解放后,在不同的历... 详细信息

西部地区作为一个重要区域,其产业结构的优化,不仅是西部地区各方面(经济、社会、资源与环境)协调发展的前提条件,更是全国产业结构优化的有机组成部分,是促进整个国民经济协调发展、各民族共同繁荣进步的重要保证。解放后,在不同的历史时期,由于国际国内诸多方面因素的影响,西部地区在全国产业结构总体布局中充当的角色也在不断地发生着变化,但其发展变化的轨迹并不是按照比较优势、规模经济和区域分工原则来运行的。

关键词：西部地区产业结构演进协调发展区域分工产业结构优化中国规模经济角色发展变化前提条件

大学生在高校教学质量管理中的主体地位和作用

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江苏教育学院学报（社会科学版） 2004年第2期20卷 32-34页

作者：李阳生茶世俊中南大学湖南长沙410083 北京大学教育学院北京100871

教师授课质量是影响大学生学习主体性的主要因素 ,大学生参与教学管理有助于提高教师授课质量 ,参与的核心环节包括教学评价、方法研讨和课程优化。学生参与教学质量管理 ,必须以转变观念为先导、以政策和制度为保障、以组织建设抓落实。

关键词：学习主体性授课质量学生参与保证机制

从世界部分产油国提高采收率的措施看地球物理技术发展

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特种油气藏 2003年第2期10卷 14-16页

作者：楚泽涵李艳华蔡智鸣封锡强石油大学北京102200 北京大学北京100871 中油辽河石油勘探局辽宁盘锦124020

统计分析世界部分产油国家提高石油采收率的增产措施的发展趋势 :热采是目前提高采收率的主要方法 ,注CO2 增产的方法发展最快 ,而注聚合物的方法在国外已经逐渐淘汰。根据这些情况 ,地球物理技术的发展要考虑适当提高下井仪器的温度性... 详细信息

统计分析世界部分产油国家提高石油采收率的增产措施的发展趋势 :热采是目前提高采收率的主要方法 ,注CO2 增产的方法发展最快 ,而注聚合物的方法在国外已经逐渐淘汰。根据这些情况 ,地球物理技术的发展要考虑适当提高下井仪器的温度性能指标 ,加强地层孔隙中流体成分和性质的研究 ,尤其是在地层温度。

关键词：世界产油国提高采收率地球物理技术增产措施

THE PHYSICAL ENTROPY OF SINGLE CONSERVATION LAWS

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Journal of Computational Mathematics 1998年第5期16卷 437-444页

作者： (Department of Mathematics, Peking university, beijing\ 100871, China) beijing Univ Dept Math Beijing 100871 Peoples R China

By means of the comparisons with the formulas in statistical mechanics and thermodynamics, in this paper it is demonstrated that for the single conservation law partial derivative(t)u + partial derivative(x)f(u) = 0, if the flux function f(u) is convex (or concave), then, the physical entropy is S = -f(u); Furthermore, if we assume this result can be generalized to any f(u) with two order continuous derivative, from the thermodynamical principle that the local entropy production must be non-negative, one entropy inequality is derived, by which the O.A. Olejnik's famous E- condition can be explained successfully in physics.

关键词： conservation laws entropy entropy production

Some Results on the Multiplier Conjecture for the Case n=5n_1

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Acta Mathematica Sinica,English Series 1998年第4期14卷 535-540页

作者： Wan Zhaoze, Department of Mathematics, Peking university, beijing\ 100871, China Department of Mathematics Peking University Beijing China

Using the method presented in [1], we obtain some new results which improve on the result of MacFarland’s theorem (see [2]) in this case.

关键词： Difference sets Multiplier CH-equations

CORRELATION BETWEEN STRESS COMPONENTS AND STRESS CORROSION CRACKS IN BRASS Lecturer,Department of Materials Physics,university of Science and Technology beijing,beijing 100083,China

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Acta Metallurgica Sinica(English Letters) 1992年第9期5卷 178-182页

作者： QIAO Lijie LIU Rui XIAO Jimei university of Science and Technology beijing,beijing,China

The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.

关键词： stress corrosion cracking stress compoonent brass ammonia solution

INFINITE ELEMENT METHOD FOR THE EXTERIOR PROBLEMS OF THE HELMHOLTZ EQUATIONS

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Journal of Computational Mathematics 2000年第6期18卷 657-672页

作者： Lung-an Ying (School of Mathematical Sciences, Peking university, beijing\ 100871, China) 北京大学北京 100871

There are two cases of the exterior problems of the Helmholtz equation. If λ ≥ 0 the bilinear form is coercive, and if λ < 0 it is the scattering problem. We give a new approach of the infinite element method, which enables us to solve these exterior problems as well as corner problems. A numerical example of the scattering problem is given. [ABSTRACT FROM AUTHOR]

关键词： Helmholtz equation exterior problem infinite element method

Kinetic characteristics of continuous flow polymerase chain reaction chip: A numerical investigation

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Science China(Technological Sciences) 2010年第7期53卷 1967-1972页

作者： WANG ShiYing1 & WANG Wei2,3 1 School of Physics, Peking university, beijing\ 100871, China 2 Institute of Microelectronics, Peking university, beijing\ 100871, China 3 National Key Laboratory of Science and Technology on Micro/Nano Fabrication, beijing\ 100871, China 1. School of Physics Peking University Beijing 100871 China2. Institute of Microelectronics Peking University Beijing 100871 China3. National Key Laboratory of Science and Technology on Micro/Nano Fabrication Beijing 100871 China

Continuous flow PCR (polymerase chain reaction) chip holds impressive advantages compared to micro chamber PCR chip. In order to have better understanding of kinetic characteristics of continuous flow PCR chip, a comprehensive mathematical model is presented in this paper, including melting, annealing and extension phases of a typical PCR process which has the essence of a convection-diffusion-reaction system. Using this model, we can simulate the PCR process in series of reaction cycles. Numerical results show that the average sample velocity plays a significant role in affecting the amplification efficiency. Also, appropriate combination of the PCR mixture is important for high-quality DNA amplification. Giving a large initial DNA concentration range, the continuous flow PCR scheme holds excellent real-time detection ability theoretically. The present numerical model bridges the temperature distribution to the real DNA amplification, and thereby is able to successfully predict continuous flow PCR properties which are important for the chip design.

关键词： continuous flow PCR chip numerical simulation convection-diffusion-reaction system