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991.
工业化、城市化促使家庭和社会在各个方面都发生了重大变革.本文试图通过分析19世纪末20世纪初美国近代城市化完成后美国家庭开始出现的一些变化,指出它们对美国社会的积极的和消极的影响,这将有助于我们更好地认识并理解当代美国家庭问题,也能为中国建立和完善社会主义家庭制度提供一些借鉴和启示.  相似文献   
992.
Interestisrapidlyemergingintheexplorationofmetalnanoparticlesforthedetectionofvariouskindsofmolecules.ExcellentexamplesincludeDNAdetectionbycomplimentaryinteractionsofthiol \|containingDNAattachedtogoldnano particles[1] ,potassiumionsensorsbyusing 15 crown …  相似文献   
993.
A new approach based on the concept of the diversity increment is applied to reconstruct a phylogeny. The phylogeny of the Eutherian orders use concatenated H-stranded amino acid sequences, and the result is consistent with the commonly accepted one for the Eutherians. Foundation item: Supported by the National Natural Science Foundation of China ( 30170214) and the Open Foundation of the State Key Laboratory of Software Engineer, Wuhan University, China. Biography: Shi Feng ( 1966- ), male, Ph. D, Associate professor, research direction: bioinformatics.  相似文献   
994.
The Analytic Network Process (ANP) is a multicriteria theory of measurement used to derive relative priority scales of absolute numbers from individual judgments (or from actual measurements normalized to a relative form) that also belong to a fundamental scale of absolute numbers. These judgments represent the relative influence, of one of two elements over the other in a pairwise comparison process on a third element in the system, with respect to an underlying control criterion. Through its supermatrix, whose entries are themselves matrices of column priorities, the ANP synthesizes the outcome of dependence and feedback within and between clusters of elements. The Analytic Hierarchy Process (AHP) with its independence assumptions on upper levels from lower levels and the independence of the elements in a level is a special case of the ANP. The ANP is an essential tool for articulating our understanding of a decision problem. One had to overcome the limitation of linear hierarchic structures and their mathematical consequences. This part on the ANP summarizes and illustrates the basic concepts of the ANP and shows how informed intuitive judgments can lead to real life answers that are matched by actual measurements in the real world (for example, relative dollar values) as illustrated in market share examples that rely on judgments and not on numerical data. Thomas L. Saaty holds the Chair of University Professor, Katz Graduate School of Business, University of Pittsburgh, Pittsburgh, PA, and obtained his Ph.D. in mathematics from Yale University. Before that he was a professor at the Wharton School of the University of Pennsylvania for ten years. Prior to that he spent seven years at the Arms Control and Disarmament Agency in the State Department in Washington, DC, that carried out the arms reduction negotiations with the Soviets in Geneva. His current research interests include decision-making, planning, conflict resolution and synthesis in the brain. As a result of his search for an effective means to deal with weapons tradeoffs at the Disarmament Agency and, more generally, with decision-making and resource allocation, Professor Saaty developed The Analytic Hierarchy Process (AHP) and its generalization to dependence and feedback, the Analytic Network Process (ANP). He is co-developer of the software Expert Choice and of the software Super Decisions for decisions with dependence and feedback. He has authored or co-authored twelve books on the AHP/ANP. Professor Saaty has also written a number of other books that embrace a variety of topics, including Modern Nonlinear Equations, Nonlinear Mathematics, Graph Theory, The Four Color Problem, Behavioral Mathematics, Queuing Theory, Optimization in Integers, Embracing the Future and The Brain: Unraveling the Mystery of How It Works. His most recent book is Creative Thinking, Problem Solving & Decision Making. The book is a rich collection of ideas, incorporating research by a growing body of researchers and practitioners, profiles of creative people, projects and products, theory, philosophy, physics and metaphysics...all explained with a liberal dose of humor. He has published more than 300 refereed articles in a wide variety of professional journals. He has been on the editorial boards of Mathematical Reviews, Operations Research, Naval Research Logistics Quarterly, Mathematical and Computer Modeling, Socio-Economic Planning Sciences, Applied Mathematics Letters, and several others. He also served as consultant to many corporations and governments.  相似文献   
995.
Calcium carbonate crystallization was performed in hydrogel of hydroxypropylmethyl cellulose (HPMC). Results showed that the polyhydroxy functionalities in HPMC gel network facilitated the nucleation of aragonite which was not found in experiment without HPMC hydrogel and in experiment using methylcellulose (MC) hydrogel as template. On the other hand, due to the unique assembly of the macromolecules in HPMC hydrogel network, which was different from other hydrogels used in some previous reports, particular crystal morphology, corncob-like CaCO_3, was obtained for the first time.  相似文献   
996.
通过对AC-3系统的结构和功能的分析,论述了该系统的内在工作原理及应用前景.  相似文献   
997.
ECM模型对固定资产投资的实证分析   总被引:4,自引:0,他引:4  
本文通过协整检验和误差修正模型,实证发现财政支出和利用外资是影响固定资产投资的重要因素.从长期和短期来看财政支出和利用外资对固定资产投资的影响都很显著,且财政支出的影响大于利用外资的影响.  相似文献   
998.
Fibre channel storage area networks (FC-SAN) are effective solutions to address storage management problems caused by very large volumes of data. But the expense of fibre channel devices limits FC-SAN applications. The use of IP networks instead of fibre channel networks will reduce SAN cost, but will also reduce the performance. Therefore, small computer system interface (SCSI) devices were considered to replace FC disks to reduce the SAN cost. A driver for the FC network adapter and the FC target, designed and implemented to support this structure, obeys the SCSI protocol and works in target mode with 200 MB/s bandwidth. The FC target architecture and implementation were compared with the FC initiator.The SCSI command transfer process in the FC layer was described. The performance test results show that the maximum I/O throughput reachs 167 MB/s for read requests and 196 MB/s for write requests (FC bandwidth is 200 MB/s), verifying that the FC target is very efficient. The modularization, efficiency, and low cost of the FC target will enable SAN and fibre channel to be more widely used in applications.  相似文献   
999.
大鼠生理性缺铁状态的初步验证   总被引:2,自引:0,他引:2  
在标准饲养条件下,对大鼠生长期的血液学参数进行了动态观察,发现大鼠在长期存在生理性缺铁状态。这与以往文献中记载的营养性铁缺乏的概念和机理不相同。营养性铁缺乏是指食物中可利用铁不足导致体内铁缺乏甚至贫血,我们提出的生理性缺陷铁状态是指,人和动物在生长期血红蛋白(hemoglobin,Hb)的合成因受铁代谢一系列机制的制约,即使食物中营养成分齐全和富足,也不能避免的相对低铁状态。其生化特征是红细胞游离原卟啉(free erythrocyte protoporphyrin,FEP)与Hb的比值(FEP/Hb)下降,而营养性铁缺乏则表现为FEP/Hb比值升高,二者可以界定。  相似文献   
1000.
The current study was to investigate mRNA expression of cyclin D2 and p16 during the transition from cardiac myocyte hyperplasia to hypertrophy. Cultured cardiac myocytes (CM) and fibroblasts (FC) obtained from 1-day-old Sparague-Dawley rats were used in this study. We have determined (1) hyperplasia by cell growth curve and fluorescence activated cell sorting (FACS); and (2) ultrastructure by electron microscope observation; and (3) expresions of cyclin D2 mRNA and p16 mRNA by using in situ hybridization and image analysis. The results were shown (1) Results of cell growth curve and FACS analysis showed CM could proliferate in the first 3 cultured days (4 days in postnatal development). But the ability decreased quickly, concomitant with the differentiation. (2) The ultrastructure of CM showed the large amount of myofilaments and mitochondrion and FC showed moderate amount of rough endoplasmic reticulum. (3) The expression of cyclin D2 mRNA in 3−, 4−, 5−day CM group was 0.89 times (p<0.05), 0.80 times (p<0.05) and 0.56 times (p<0.01) of that in 1-day group respectively. P16 mRNA in 2−, 3−, 4−, 5−day CM group were 1.63 times (p<0.01), 1.72 times (p<0.01), 1.99 times (p<0.01) and 2.84 times (p<0.01) of that in 1−day group respectively. It can be concluded that cultured neonatal rat cardiac myocytes could proliferate during the first 3 cultured days, but the ability of proliferation decreased, from the fourth day, concomitant with differentiation. Cyclin D2 and p16 have the key roles during the transition from myocyte hyperplasia to hypertrophy. Biography: Zhang Yu-xia (1974-), female, Master, research direction: cardiovascular pathology.  相似文献   
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