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How do we remain healthy, for the most parts, in the midst of an environment teeming with opportunistic and infectious microbes, potential carcinogens and allergens? The fact is that our immune system, by and large, does a fine job in protecting us. It is therefore important to understand the organization of the immune network, which is broadly categorized into two groups: innate and adaptive. Cells involved in innate immunity are the first to come into contact with invading microbes, similar to the border security force, and respond rapidly but in a non-specific manner. On the other hand, the cells involved in adaptive immunity are slower to respond but act in a very specific manner. Though the primary response is slow, the secondary response is much faster and demonstrates memory. This article will focus on some important features and key players involved in the adaptive immune response. The first part deals with the humoral immune response mediated mainly by immunoglobulins produced by the B cells. The second part deals with T cells, the Major Histocompatibility Complex (MHC)-encoded molecules, and Recombination Activating Genes (RAG) responsible for generating diverse B-cell receptors (BCR) and T-cell receptors (TCR). With the advent of newer and smarter infectious agents, it is important to understand the working of the immune network as more research in this area may facilitate the development of better protective strategies.  相似文献   
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Pleurotus sajor-caju (Fr.) Singer was cultivated on selected agro wastes viz. cotton stalks, groundnut haulms, soybean straw, pigeon pea stalks and leaves and wheat straw, alone or in combinations. Cotton stalks, pigeon pea stalks and wheat straw alone or in combination were found to be more suitable than groundnut haulms and soybean straw for the cultivation. Organic supplements such as groundnut oilseed cake, gram powder and rice bran not only affected growth parameters but also increased yields. Thus bioconversion of lignocellulosic biomass by P. sajor-caju offers a promising way to convert low quality biomass into an improved human food.  相似文献   
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We present a curriculum that prepares students for supporting large Enterprise Information Systems (EIS). EIS is best explained through the evolution of Enterprise Resource Planning (ERP). These systems evolved over the last years driven by (1) changing business requirements and (2) new development capabilities provided by technologies evolution and software vendors’ innovation. These developments led to a new discipline—Enterprise Information Systems, which deals with issues whose focus is on creating and sustaining business benefits through the utilization of corporate IT infrastructure assets. Currently, EIS knowledge is essentially acquired on the job after substantial time of experience building and longer career ladder scale. This paper presents an experience of a curriculum implementation that prepares students for the pervasive EIS landscape in meeting today’s corporate needs. Our IT-based educational approach is evaluated as an alternative to prevailing Business-based approaches to EIS instruction. In this IT-rooted approach, the curriculum is divided into four sections: a Core IT block of courses followed by two progressive-levels of advanced EIS-related specialized subjects, and an industry-oriented field-training experience. Initially, a Core IT background provides a foundation for IT innovation in developing EIS components at sophomore-level. A junior-level of specialized instruction introduces integrated modules which form EIS platforms. Finally, supporting technologies of EIS-related processes and workflows are presented at senior-level of specialized EIS instruction. An assessment case study of the proposed Enterprise System programs is carried out through which we discuss the results of the curriculum performance.  相似文献   
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This review evaluated the effects of precooling via cold water immersion (CWI) and ingestion of ice slurry/slushy or crushed ice (ICE) on endurance performance measures (e.g. time-to-exhaustion and time trials) and psychophysiological parameters (core [Tcore] and skin [Tskin] temperatures, whole body sweat [WBS] response, heart rate [HR], thermal sensation [TS], and perceived exertion [RPE]). Twenty-two studies were included in the meta-analysis based on the following criteria: (i) cooling was performed before exercise with ICE or CWI; (ii) exercise longer than 6?min was performed in ambient temperature ≥26°C; and (iii) crossover study design with a non-cooling passive control condition. CWI improved performance measures (weighted average effect size in Hedges’ g [95% confidence interval]?+?0.53 [0.28; 0.77]) and resulted in greater increase (ΔEX) in Tskin (+4.15 [3.1; 5.21]) during exercise, while lower peak Tcore (?0.93 [?1.18; ?0.67]), WBS (?0.74 [?1.18; ?0.3]), and TS (?0.5 [?0.8; ?0.19]) were observed without concomitant changes in ΔEX-Tcore (+0.19 [?0.22; 0.6]), peak Tskin (?0.67 [?1.52; 0.18]), peak HR (?0.14 [?0.38; 0.11]), and RPE (?0.14 [?0.39; 0.12]). ICE had no clear effect on performance measures (+0.2 [?0.07; 0.46]) but resulted in greater ΔEX-Tcore (+1.02 [0.59; 1.45]) and ΔEX-Tskin (+0.34 [0.02; 0.67]) without concomitant changes in peak Tcore (?0.1 [?0.48; 0.28]), peak Tskin (+0.1 [?0.22; 0.41]), peak HR (+0.08 [?0.19; 0.35]), WBS (?0.12 [?0.42; 0.18]), TS (?0.2 [?0.49; 0.1]), and RPE (?0.01 [?0.33; 0.31]). From both ergogenic and thermoregulatory perspectives, CWI may be more effective than ICE as a precooling treatment prior to exercise in the heat.  相似文献   
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A 30‐s ‘all‐out’ power protocol was studied in four groups of racing cyclists including internationals (n = 8), Category 1 (n = 10), Category 2 (n = 15) and Category 3 (n = 11). Following warm‐up each subject completed five trials interspersed by 3 min of low intensity exercise on an ergowheel racing cycle ergometry system at a power output of 15 W kg–1 body weight, generated at 130 rev min–1. Temporal indices of performance included delay time (DT) to achieve the power criterion, total time (TT) of the maintenance of the power criterion and the ratio of TT/DT. ‘Explosive’ leg strength was assessed from a vertical jump. The results indicated that international and Category 1 cyclists had lower DT (2.2 ± 0.1s and 2.1 +0.0s, respectively; P<0.05), higher TT (28.1 ±0.7s and 27.0+0.7s, respectively; P<0.05) and elevated TT/DT (12.8 and 12.9, respectively; P<0.01). ‘Explosive’ leg strength was also higher (P<0.05) in the internationals than in the other groups of cyclists. The protocol provides a sport‐related method for the assessment of short term endurance performance ability in racing cyclists which may be of value in identifying the anaerobic capability of individual cyclists.  相似文献   
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The insulin-like growth factor 1 (IGF1) gene is a member of the group of somatotropin axis genes that play a significant role in cell proliferation and growth of muscles. Here, we searched for polymorphisms in buffalo IGF1 and found two novel single nucleotide polymorphisms (SNPs), G64A and G280A, in the noncoding sequences of exon 1 and exon 4, respectively. Statistical analysis of different genotypes showed that the individuals with GG genotypes had significantly (P<0.05) higher body weight (BW) and average daily gain (ADG) than those with other genotypes at ages of 3–6 months in G64A SNP and 6–9 months in G280A SNP. The combined genotypes of these two SNPs produced three haplotypes, GG/GG, AG/AG, and AA/AA, which were significantly associated (P<0.0001) with BW and ADG at an age from 3 to 12 months. Buffaloes with the homozygous GG/GG haplotype showed higher growth performance than other buffaloes. The two SNPs were correlated with mRNA levels of IGF1 and IGF1 receptor (IGF1R) in semitendinosus muscle as well as with the serum concentration level of IGF1. Also, buffaloes with GG/GG haplotype showed higher mRNA and serum concentration levels. The data revealed that these two SNPs could be valuable genetic markers for selection of Egyptian buffaloes for better performance in the population.  相似文献   
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Educational technology research and development -  相似文献   
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