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This paper reports research on the effects of variations in injection velocity and permeability on the heat transfer and flow through a highly porous medium between two horizontal parallel plates situated at constant distance with constant suction by the upper plate. Due to this type of variation in injection velocity and in permeability the flow becomes three dimensional. The governing equations are solved by adopting complex variable notations to obtain the expressions for the velocity and temperature field. The skin-friction along the main flow direction and rate of heat transfer are discussed with the help of graphs.  相似文献   
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Quantitative trait loci (QTL) analysis was conducted in bread wheat for 14 important traits utilizing data from four different mapping populations involving different approaches of QTL analysis. Analysis for grain protein content (GPC) sug- gested that the major part of genetic variation for this trait is due to environmental interactions. In contrast, pre-harvest sprouting tolerance (PHST) was controlled mainly by main effect QTL (M-QTL) with very little genetic variation due to environmental interactions; a major QTL for PHST was detected on chromosome arm 3AL. For grain weight, one QTL each was detected on chromosome arms 1AS, 2BS and 7AS. QTL for 4 growth related traits taken together detected by different methods ranged from 37 to 40; nine QTL that were detected by single-locus as well as two-locus analyses were all M-QTL. Similarly, single-locus and two-locus QTL analyses for seven yield and yield contributing traits in two populations respectively allowed detection of 25 and 50 QTL by composite interval mapping (CIM), 16 and 25 QTL by multiple-trait composite interval mapping (MCIM) and 38 and 37 QTL by two-locus analyses. These studies should prove useful in QTL cloning and wheat improvement through marker aided selection.  相似文献   
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饮食是人类物质生活最基本的内容之一。同时,一个地区、一个群体的饮食文化往往是一个地区、一个群体文化的浓缩。因此,罗布泊维吾尔人的多姿多彩的文化中独具特色的应是饮食文化。本文根据田野调查资料,对罗布泊维吾尔族传统饮食文化做一概述。  相似文献   
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The correlation between antioxidant capacity and oxidative damage during aging has been reported in several tissues in different species. Glutathione-S-transferases (GST) can metabolise endogenous and exogenous toxins and carcinogens by catalysing the conjugation of diverse electrophiles with reduced glutathione (GSH). We observe a significant (P < 0.001) increase in plasma GST activity as a function of human age (r = 0.5675). A significant (P < 0.001) positive correlation (r = 0.8979) is observed between GST activity and total plasma antioxidant potential measured as ferric reducing ability of the plasma (FRAP). GST activity and red cell intracellular GSH also show a significant positive correlation (r = 0.7014). We hypothesize that the increased activity of plasma GST is a manifestation of increased generation of ROS and a concomitant decrease in the level of plasma antioxidant capacity during aging.  相似文献   
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The Mach number, angle of attack and altitude of operation for an interceptor vary widely during the course of its trajectory. As a result, the interceptor Center of Pressure (CP) locations move significantly around a given Center of Gravity (CG) location at these operating conditions. This results in an inevitable variation in aerodynamic static stability leading to stable and unstable operating regions. In order to ensure good speed of response during the interceptor homing phase, lesser static stability is desirable. Hence the requirement to handle aerodynamic instability at some other operating conditions in the interceptor envelope become inevitable. Since flexibility has a strong bearing on autopilot design, it becomes necessary to control unstable operating points in the presence of flexibility modes. Despite the static stability variation, aerodynamic design can control the level of maximum instability of the configuration. Hence the maximum static instability the autopilot can handle has to be specified for aerodynamic configuration design. This paper brings out the limitations of autopilot design in controlling an unstable interceptor with low bending mode frequencies in terms of maximum instability the autopilot design can handle, which serves as an important input for aerodynamic design.  相似文献   
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Mitochondrial diseases are a heterogeneous group of disorders in which a primary mitochondrial dysfunction is proven by morphological, biochemical, and genetic examinations. The mitral valve has important function in the regulation of blood flow from one chamber to another. Often, the mitral valve becomes abnormal with age, in Rheumatic fever or it is abnormal from birth (Congenital) or it can be destroyed by infection i.e. bacterial endocarditis and needs replacement. Myocardial function depends on energy produced by mitochondria and in any of these disease conditions, mitochondrial functions and enzyme activities may be impaired. With this in view, we analyzed the relationship between preoperative clinical conditions (as per New York heart Association) and extent of mitochondrial enzyme activities in damaged Human mitral valve in two types of heart disease such as Rheumatic Heart Disease (RHD) and Bacterial Endocarditis (BE). Thirty nine Patients undergoing cardiopulmonary bypass (CPB) for routine valvular heart surgery were included in the study. Controls included 11 normal porcine mitral valve samples without any evidence of heart disease. Mitochondrial enzymes like cytochrome oxidase (COX), succinate dehydrogenase (SDH), malate dehydrogenase (MDH), citrate synthase (CS) and ATPase were determined. Mitochondrial COX, SDH, CS and Total ATPase activities were significantly decreased in disease condition like BE and RHD when compared with control (P<0.001). On the other hand as per New York Heart Association (NYHA) preoperative clinical classification, all the mitochondrial enzymes were significantly (p<0.05) impaired in class IV as compared with NYHA class I, II and III. Present study shows that impairment in the mitochondrial enzymes activities are more pronounced in bacterial endocarditis (BE). It also indicates that damage to mitochondrial enzymes are most pronounced in NYHA class IV.  相似文献   
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In this paper, a novel neighborhood based document smoothing model for information retrieval has been proposed. Lexical association between terms is used to provide a context sensitive indexing weight to the document terms, i.e. the term weights are redistributed based on the lexical association with the context words. A generalized retrieval framework has been presented and it has been shown that the vector space model (VSM), divergence from randomness (DFR), Okapi Best Matching 25 (BM25) and the language model (LM) based retrieval frameworks are special cases of this generalized framework. Being proposed in the generalized retrieval framework, the neighborhood based document smoothing model is applicable to all the indexing models that use the term-document frequency scheme. The proposed smoothing model is as efficient as the baseline retrieval frameworks at runtime. Experiments over the TREC datasets show that the neighborhood based document smoothing model consistently improves the retrieval performance of VSM, DFR, BM25 and LM and the improvements are statistically significant.  相似文献   
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Scaffolding provides content-area teachers (CATs) with an effective means to integrate language instruction into content-area instruction for English language learners (ELLs). Data for this study were derived from 33 CAT discussions while they were pursuing professional development in an American university classroom over 32 weeks. The discussions yielded 408 scaffolding statements that were coded and analyzed. The findings identified linguistic, conceptual, social and cultural scaffolding as part of the CATs’ personal practical knowledge. Also, the findings demonstrated that CATs’ knowledge of cultural scaffolding is limited in comparison to other scaffolding strategies. The findings have an impact on the nature of ELL instruction and its effectiveness.  相似文献   
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