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Abstract

A study was made of the relationship of physique and developmental level, determined by use of the Wetzel Grid, to performance of junior high boys on four fitness tests: pull-ups, 50-yd. dash, standing broad jump, and softball throw. Subjects of different physique groups (heavy, medium, and thin) who were alike developmentally (accelerated, normal, and retarded) differed more markedly in performance than did subjects of different developmental levels who were alike with regard to physique. Subjects who were medium in physique and normal in development were the best performers. Subjects of heavy physique (many overweight) were the poorest performers. This would seem to indicate the need for a restudy of classification methods, particularly when norms are to be used for evaluating performance.  相似文献   
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A substantial part of the stock of technological knowhow in any given country is determined by foreign companies. Flows of technology are reflected in part by the international pattern of patenting behaviour. This paper examines both the patent applications in the UK by foreign countries and UK patent applications abroad. It concludes that each country is exposed to a subset of world-wide technology determined by the profitability of transfer of new knowhow. Profitability is affected by the size of potential supply of new inventions in donor countries, by the attractiveness of markets for knowhow in recipient countries and by the costs of transfer.  相似文献   
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A seven channel polystyrene (PS) microchip has been constructed using a micromilling machine and a high-temperature assembling. Protein A (PA) has been immobilized by a passive sorption on the microchannel walls. Two bioaffinity assays with human immunoglobulin G (hIgG) as a ligand have been carried out. (i) PA as the receptor and fluorescently labeled hIgG (FITC-hIgG) as the ligand, (ii) PA as the receptor with hIgG as the quantified ligand and fluorescently labeled goat anti-human IgG (FITC-gIgG) as the secondary ligand. One incubation step of the assays took only 5 min instead of hours typical for enzyme-linked immunosorbent assay applications. Calibration curves of the dependence of a fluorescence signal on the hIgG concentration in a sample have been obtained in one step due to a parallel arrangement of microchannels. A mathematical model of the PA-FITC-hIgG complex formation in the chip has been developed. The values of the kinetic constant of the PA-FITC-hIgG binding (kon=5.5 m3 mol−1 s−1) and the equilibrium dissociation constant of the formed complex (Kd≤3×10−6 mol m−3) have been obtained by fitting to experimental data. The proposed microchip enables fast evaluation of kinetic and equilibrium constants of ligand-receptor bioaffinity pairs and the ligand quantification. As the use of microfluidic chips for immunoassays is often limited by price, we used procedures and chemicals that allow for an inexpensive construction and operation of the microdevice, e.g., temperature assembling as a fabrication technique, detection via an ordinary digital camera, nonspecific polystyrene as a substrate, passive sorption of biomolecules as an immobilization technique, etc.  相似文献   
89.
紧生成l—群的一个结构定理   总被引:1,自引:0,他引:1  
l-群G称为紧生成的,如果对于G的任意子集{αλ|λ∈Λ}且α=∨λ∈Λαλ存在,必存在{αλ|λ∈Λ}的有限子集a1、a2……an,使得a=∨ni=1ai。主要结果是:G∈F,则G是紧生成的当且仅当G的任一个l-子群是闭的,且Г(G)满足极小条件。  相似文献   
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Volume Contents

Contents Volume 7 2001  相似文献   
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