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21.
The Association of College and Research Libraries (ACRL) Science and Technology Section (STS) wiki was launched in 2008. This article discusses the STS wiki development, content, publicity, and its application across the science disciplines. Information about assessment and future plans for the wiki is also provided. Some of the information included in this article was presented in a panel for the 2010 United States Agricultural Information Network (USAIN) Conference.  相似文献   
22.
The genome sequence of Drosophila melanogaster   总被引:2,自引:0,他引:2  
The fly Drosophila melanogaster is one of the most intensively studied organisms in biology and serves as a model system for the investigation of many developmental and cellular processes common to higher eukaryotes, including humans. We have determined the nucleotide sequence of nearly all of the approximately 120-megabase euchromatic portion of the Drosophila genome using a whole-genome shotgun sequencing strategy supported by extensive clone-based sequence and a high-quality bacterial artificial chromosome physical map. Efforts are under way to close the remaining gaps; however, the sequence is of sufficient accuracy and contiguity to be declared substantially complete and to support an initial analysis of genome structure and preliminary gene annotation and interpretation. The genome encodes approximately 13,600 genes, somewhat fewer than the smaller Caenorhabditis elegans genome, but with comparable functional diversity.  相似文献   
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A 290-million-year-old reptilian skeleton from the Lower Permian (Asselian) of Germany provides evidence of abilities for cursorial bipedal locomotion, employing a parasagittal digitigrade posture. The skeleton is of a small bolosaurid, Eudibamus cursoris, gen. et sp. nov. and confirms the widespread distribution of Bolosauridae across Laurasia during this early stage of amniote evolution. E. cursoris is the oldest known representative of Parareptilia, a major clade of reptiles.  相似文献   
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We constructed a bacterial artificial chromosome (BAC)-based physical map of chromosomes 2 and 3 of Drosophila melanogaster, which constitute 81% of the genome. Sequence tagged site (STS) content, restriction fingerprinting, and polytene chromosome in situ hybridization approaches were integrated to produce a map spanning the euchromatin. Three of five remaining gaps are in repeat-rich regions near the centromeres. A tiling path of clones spanning this map and STS maps of chromosomes X and 4 was sequenced to low coverage; the maps and tiling path sequence were used to support and verify the whole-genome sequence assembly, and tiling path BACs were used as templates in sequence finishing.  相似文献   
27.
Species of somatostatin of higher molecular weight were present in the nerve terminals (synaptosomes) of ovine stalk median eminences and were released by depolarizing stimuli. One of these species was identified as the biologically active molecule octacosa somatostatin. Octacosa somatostatin appears therefore to be secreted into the hypothalamic-hypophyseal system, supporting the concept of a role for this peptide in regulating pituitary hormone secretion.  相似文献   
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Elevated phosphate concentrations at Safaga and Quseir, Red Sea, Egyptian coast, wererelated to some ecological and nutritional aspects of the macro-alga Cystoseira myrica during1985. The results obtained were compared with those recorded for a non-polluted control site atGhardaqa. Chemical analysis of surface seawater samples revealed that the concentrations of dissolvedphosphate at Safaga and Quseir were 3 and 20 times as much as that at Ghardaqa, respectively.The standing crop of C. myrica showed two peaks in spring and autumn. Maximum biomass yield(491 g m-2) and number of individuals (127 m-2) of C. myrica were recorded in the spring at theGhardaqa site. Quseir C. myrica samples contained significantly higher protein-N, total-N andtotal-P values but lower carbohydrate values than the Safaga and Ghardaqa samples (LSD at 1%level). Tissue N:P molar ratios for C. myrica, Laurencia papillosa and Ulva lactuca collected fromGhardaqa ranged from 68-98, compared to 30-59 for the same species collected at thephosphorus polluted sites at Safaga and Quseir. The carbon levels and the C:N ratios of C. myricaexhibited no significant variations in the three studied sites. However, the C:P ratios of Ghardaqaplants were significantly higher than those of Safaga and Quseir.  相似文献   
30.
The soybean product MON 87701 × MON 89788 expresses both the cry1Ac gene derived from Bacillus thuringiensis and the cp4 epsps (5-enolpyruvylshikimate-3-phosphate synthase) gene derived from Agrobacterium sp. strain CP4. Each biotechnology-derived trait confers specific benefits of insect resistance and glyphosate tolerance, respectively. The purpose of this study was to compare the composition of seed and forage from this combined-trait product to those of conventional soybean grown in geographically and climatically distinct regions. Field trials were conducted in the United States during the 2007 growing season, in Argentina during the 2007-2008 growing season, and in the northern and southern soybean regions of Brazil during the 2007-2008 and 2008-2009 growing seasons. Results demonstrated that the compositional equivalence of MON 87701 × MON 89788 to the conventional soybean extended across all regions and growing seasons. Further evaluation of the data showed that natural variation (region and growing season) contributed more to compositional variability in soybean, particularly for such components as isoflavones, fatty acids, and vitamin E, than transgene insertion.  相似文献   
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