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21.
1IntroductionTiledesigllalldof)erati()lloftilt.egratedmultiplewatersuppliesandhydroelectricfacilitiestol>ostutilizea1'egi()llalt-c'aterresourcecallcollstituteacolllplexanddifficultoptimizationprohleln.involvingill('tilt(-'r;('tiollofI)oliti('alalldlegalprocesses,institutiollalregulat,ionsalldengilleerillgecollolllics.Tllolastqllart('rofa(}elltur}'11aswitllessedasigllificantdevelopmelltofoptimizatiollalgol'itllllls.Tillsif('ti.it}'ilasI>een1llotivatedbytwomajorfactorsftherapidevolutiollofcom…  相似文献   
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A major consideration in the selection of a forecasting method for a specific situation is the type of pattern in the data. Before the data pattern is identified, the forecaster must recognize the dependence of any forecasting method upon the accompanying reliable database. This issue is discussed in the paper with reference to databases for international business.  相似文献   
24.
Eosinophils as mediators of antibody-dependent damage to schistosomula.   总被引:67,自引:0,他引:67  
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This article reports the effect of ageing on the microstructure, martensitic transformation, magnetic properties, and mechanical properties of Ni51Fe18Ga27Ti4 shape memory alloy. There are five specimens of this alloy aged at 573 up to 973 K for 3 h per each. This range of ageing temperature greatly affects the microstructure of the alloy. As the ageing temperature increased from 573 up to 973 K, the microstructure of Ni51Fe18Ga27Ti4 alloy gradually changed from the entirely martensitic matrix at 573 K to the fully austenitic microstructure at 973 K. The volume fraction of precipitated Ni3Ti particles increased with the ageing temperature increasing from 573 to 773 K. Further increasing the ageing temperature to 973 K decreased the content of Ni3Ti in the microstructure. The martensitic transformation temperature was decreased steadily by increasing the ageing temperature. The magnetization saturation, remnant magnetization, and coercivity increased with the ageing temperature increasing up to 773 K. A further increase in ageing temperature decreased these magnetic properties. Moreover, the hardness values were gradually increased at first by increasing the ageing temperature to 773 K, and then dramatically decreased to the lowest value at 973 K.  相似文献   
26.
Transthyretin (TTR) is a functional protein in the pancreatic β-cell. It promotes insulin release and protects against β-cell death. We now demonstrate by ligand blotting, adsorption to specific magnetic beads, and surface plasmon resonance that TTR binds to glucose-regulated proteins (Grps)78, 94, and 170, which are members of the endoplasmic reticulum chaperone family, but Grps78 and 94 have also been found at the plasma membrane. The effect of TTR on changes in cytoplasmic free Ca2+ concentration ([Ca2+]i) was abolished if the cells were treated with either dynasore, a specific inhibitor of dynamin GTPase that blocks clathrin-mediated endocytosis, or an antibody against Grp78, that prevents TTR from binding to Grp78. The conclusion is that TTR binds to Grp78 at the plasma membrane, is internalized into the β-cell via a clathrin-dependent pathway, and that this internalization is necessary for the effects of TTR on β-cell function.  相似文献   
27.
Systemic Practice and Action Research - Considering the unfortunate intensification of the Non-performing loans in Iran`s credits system makes it vital to study the current system shortcomings....  相似文献   
28.
Paramyosin and actin in schistosomal teguments   总被引:24,自引:0,他引:24  
Schistosomes are blood-dwelling trematode parasites that infect 200 million people in developing countries. The critical role served by the tegument in immune evasion and parasite homeostasis suggests that a detailed knowledge of tegumental components would be helpful in the design of new drugs and the production of vaccines. We demonstrate here, by immunoelectron microscopy, that the cytoskeletal proteins actin and paramyosin are organized into major tegumental structures of Schistosoma mansoni. The surface spines are composed of paracrystalline arrays of actin filaments. Actin is also present in areas recovering from damage, implying an important role for this structural protein in tegumental repair. Paramyosin exists predominantly in the tegument in a non-filamentous form, the membrane-bounded elongate bodies. The localization of this protein to the tegument of the parasite is the likely basis for resistance to S. mansoni observed in mice immunized with paramyosin (refs 1, 2 and T. P. Flanigen et al., in preparation).  相似文献   
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This study compared the microstructure and mechanical characteristics of AA6061-T6 joints produced using friction stir welding (FSW), friction stir vibration welding (FSVW), and tungsten inert gas welding (TIG). FSVW is a modified version of FSW wherein the joining specimens are vibrated normal to the welding line during FSW. The results indicated that the weld region grains for FSVW and FSW were equiaxed and were smaller than the grains for TIG. In addition, the weld region grains for FSVW were finer compared with those for FSW. Results also showed that the strength, hardness, and toughness values of the joints produced by FSVW were higher than those of the other joints produced by FSW and TIG. The vibration during FSW enhanced dynamic recrystallization, which led to the development of finer grains. The weld efficiency of FSVW was approximately 81%, whereas those of FSW and TIG were approximately 74% and 67%, respectively.  相似文献   
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