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121.
目的:分析空腹和餐后,有氧运动对II糖尿病患者血浆脂蛋白特性、前B1一HDL浓度、体外HDL,清除巨噬细胞胆固醇和抑制LDL氧化能力的作用。方法:受试者分为三组,健康对照组(A,n=11);II糖尿病运动组(B,n=11);II糖尿病不运动组(C,n=11)。A和B组进行4个月的有氧运动。所有受试者都进行一次脂肪餐负荷试验以分析各种参数的基础值和最后值。结果:运动没有改变体重、BMI、血浆总胆固醇、LDL、HDL、TG、胰岛素浓度和HOMA—IR,但是降低了腰围。HDL3没有变化,有氧运动没有改变其清除细胞胆固醇的能力。糖尿病患者进行有氧运动能改善饥饿状态下HDL,阻止LDL最大氧化率能力的15%,降低餐后血浆前β1-HDL浓度,表明增加前β1-HDL向大的、更加成熟的HDL转化。就此而言,规律的有氧运动增加健康人空腹和餐后的HDL2和TG,增加糖尿病患者空腹时HDL2和TG。结论:研究结果显示糖尿病患者进行有氧运动改善HDL抑制LDL氧化的效力,帮助HDL成熟。这个结果不依赖于胰岛素抵抗的改变和血浆HDL浓度的变化。 相似文献
122.
Modeling and multi-objective optimization of a gasoline engine using neural networks and evolutionary algorithms 总被引:1,自引:0,他引:1
José D.MARTNEZ-MORALES Elvia R.PALACIOS-HERNNDEZ Gerardo A.VELZQUEZ-CARRILLO 《浙江大学学报(A卷英文版)》2013,14(9):657-670
In this paper, a multi-objective particle swarm optimization (MOPSO) algorithm and a nondominated sorting genetic algorithm II (NSGA-II) are used to optimize the operating parameters of a 1.6 L, spark ignition (SI) gasoline engine. The aim of this optimization is to reduce engine emissions in terms of carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx), which are the causes of diverse environmental problems such as air pollution and global warming. Stationary engine tests were performed for data generation, covering 60 operating conditions. Artificial neural networks (ANNs) were used to predict exhaust emissions, whose inputs were from six engine operating parameters, and the outputs were three resulting exhaust emissions. The outputs of ANNs were used to evaluate objective functions within the optimization algorithms: NSGA-II and MOPSO. Then a decision-making process was conducted, using a fuzzy method to select a Pareto solution with which the best emission reductions can be achieved. The NSGA-II algorithm achieved reductions of at least 9.84%, 82.44%, and 13.78% for CO, HC, and NOx, respectively. With a MOPSO algorithm the reached reductions were at least 13.68%, 83.80%, and 7.67% for CO, HC, and NOx, respectively. 相似文献
123.
According to the principles of simultaneous equilibrium and electronic charge neutrality, the thermodynamics of Zn(II)-NaOH-H2O system was studied in this paper. Varying the concentration of sodium hydroxide, in range of 0- 400 g/L, the distribution law of all zinc species and the mathematical model of equilibrium concentration of zinc in the system were obtained. The relative errors between theoretic calculation and the experimental values of total concentration of zinc were analyzed, and the absolute average error is only 0.129 8%. The mathematical model and the thermodynamic data are believable. 相似文献
124.
125.
Photosystem II (PSII) is a fascinating photosynthesis-involved enzyme, participating in sunlight-harvest, water splitting, oxygen release, and proton/electron generation and transfer. Scientists have been inspired to couple PSII with synthetic hierarchical structures via biomimetic assembly, facilitating attainment of natural photosynthesis processes, such as photocatalytic water splitting, electron transfer and ATP synthesis, in vivo. In the past decade, there has been significant progress in PSII-based biomimetic systems, such as artificial chloroplasts and photoelectrochemical cells. The biomimetic assembly approach helps PSII gather functions and properties from synthetic materials, resulting in a complex with partly natural and partly synthetic components. PSII-based biomimetic assembly offers opportunities to forward semi-biohybrid research and synchronously inspire optimization of artificial light-harvest micro/nanodevices. This review summarizes recent studies on how PSII combines with artificial structures via molecular assembly and highlights PSII-based semi-natural biosystems which arise from synthetic parts and natural components. Moreover, we discuss the challenges and remaining problems for PSII-based systems and the outlook for their development and applications. We believe this topic provides inspiration for rational designs to develop biomimetic PSII-based semi-natural devices and further reveal the secrets of energy conversion within natural photosynthesis from the molecular level. 相似文献
126.
柏林大学办学模式的确立:理性的凯旋 总被引:1,自引:0,他引:1
200年前柏林大学的建立及其办学模式在全世界的传播,是欧洲文明进程特别是启蒙运动的成果。柏林大学模式已经超越自身,代表着欧洲理性思想。洪堡关于教学自由、教学与研究统一、科学统一性的办学思想,是启蒙思想的具体体现。自由和竞争等制度因素在柏林大学的成功实践中发挥了重要作用。 相似文献
127.
洪堡2010,何去何从 总被引:1,自引:0,他引:1
2010年10月10日,柏林洪堡大学盼来建校200周年,同时也迎来一位新校长。既有传承,也有新生。然而,200周年校庆之扛鼎之作《洪堡备忘录2010》欲求远眺未来却深陷对历史的纷争,就职典礼上新任校长理应展现蓝图却呼吁以洪堡为标杆。以此事件为主线,以洪堡模式核心理念的“教学与科研相统一”为切入点,通过对德国高等教育的现状与历史的分析,作者认为,旨在创建一所“典范大学”的洪堡模式自始至终未能在德国本土实现,且渐行渐远,尽管柏林大学作为“现代大学之母”与“现代之原型”被世界广为追捧乃至复制,在德国亦无尽魂牵梦绕。洪堡理念的百年失意恰恰源于教学与科研的世纪纠结。走在教学与科研之间,洪堡2010前途未卜。 相似文献
128.
Anthea Seles 《Archival Science》2006,6(3-4):393-405
Contemporary Church recordkeeping has been an area all too often ignored by historians and archivists. There were two significant
events in the last 140 years that defined the types of records created and maintained within the Church namely: Vatican I
and Vatican II. After the suspension of Vatican I and the promulgation of Pastor Aeternus, we begin to see a centralization in ecclesiastical governance structures, due in part to interpretations of papal primacy.
This centralization of Church authority eventually impinged upon the recordkeeping processes of dioceses. However after Vatican
II the pendulum shifted with the promulgation of the Decree Concerning the Pastoral Office of the Bishop and the re-introduction of the tenet of collegiality. The promulgation of this document and others caused a de-centralization
of Church recordkeeping practices. Using the Archdiocese of Vancouver as a case study this paper will attempt to show recordkeeping
changes that occurred after Vatican I and Vatican II and the impact these councils had on archdiocesan administration. 相似文献
129.
遵循运动处方原理和模式,以太极拳运动防治"肝肾阴虚证"高血压病为例,探讨其临床实效性,实验结果表明:1)16周实验后,实验组C-反应蛋白(CRP)浓度降低与实验前相比有差异。而对照组没有显著性变化。2)实验组收缩压较实验前有显著性降低,而舒张压有极其显著性降低。且实验前后收缩压、舒张压的差值与对照组相比,收缩压有显著差异,舒张压有极其显著性差异。3)运动后受试者感觉心情愉悦、平衡能力增强、头脑清醒、身体轻松、精力充沛、无不适感等情况,实验组为95.15%,对照组为76.08%,差异显著。受试者自觉失眠、多梦、头晕、耳鸣、乏力、烦燥等不适症状得到改善,其中实验组为90.33%,对照组为87.53%;实验组在医生指导下减少用药量,感觉轻松自如、精力充沛,自觉症状改善,血压呈下降和稳定状态,实验组无自觉症状者为41.68%,而对照组无自觉症状者为31.83%,有显著差异,表明太极拳运动处方防治高血压病效果显著,具有临床指导意义。 相似文献
130.
王明明 《唐山师范学院学报》2014,(4):21-22
分数的发展史是汉语史的重要组成部分,分数研究方面论著亦颇多,然而学者们研究分数的材料多以传世文献为主,他们取得了很大的成绩,却也有很大的局限,主要问题是很难做到全面掌握材料,故论及多有缺陷。《岳麓书院秦简(贰)》作为中国最早的数学书,分数大量应用,对早期分数研究的价值不言而喻。 相似文献