874 resultados para Saline adaptation


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野大豆和锦鸡儿,同属豆科植物。前者是一年生自交植物,后者是多年生异交植物;一个是大豆的种质资源,另一个是固沙植物;一个具有耐盐适应,另一个能够抗旱。本文首先结合同工酶分析结果,通过随机扩增多态性DNA(RAPD]标记研究了锦鸡儿和野大豆群体的分子生态学特征。然后用限制性内切酶消化了单态的野大豆群体扩增产物以提高RAPD标记检测野大豆DNA多态性的能力。并且根据锦鸡儿群体的RAPD谱估算了每位点上的等位基因频率,分别用Shannon信息指数和Nei指数估测了各群体的遗传变异。最后,在以上研究的基础上结合我们实验室有关锦鸡儿和野大豆的形态,种子蛋白或同工酶方面的分析得到以下结论: 1]在本文的实验条件下,RAPD标记的重复性很好,使有关锦鸡儿和野大豆群体分子生态学的研究结果有了可靠的基础。 2]RAPD标记的显性特征使实验中确定显、隐性等位基因频率困难较大。用估测的显、隐性等位基因频率通过Shannon信息指数估算群体遗传多样性可能更适合于异交植物。 3)用限制性内切酶消化随机扩增产物后,能够提高RAPD标记检测野大豆群体DNA多态性的能力。4]按RAPD多态位点比率排列毛乌素沙地锦鸡儿各群体为:硬粱群体<沙丘群体<硬粱覆沙群体<毛条群体<滩地覆沙群体<软梁覆沙群体。按遗传多样性排列各群体为:硬粱群体<硬梁覆沙群体<沙丘群体<软梁覆沙群体<毛条群体<滩地覆沙群体。反映了RAPD多态位点比率与遗传多样性在检测群体DNA多态性能力上的异同。 5]毛乌素沙地锦鸡儿群体间 存在着强大的基因流,其高度异交性与生态过渡带可能是一致的。 6]根据同工酶、种子蛋白的分析结果,硬粱覆沙群体的基因多样性在毛鸟素沙地锦鸡儿各群体中是最高的。然而,根据DNA多态性的研究结果,硬粱覆沙群体的基因多样性在各个群体中仅大于硬梁群体。反映了锦鸡尔表型分化与基因型分化的差异。7]就本文的研究结果来看,野大豆群体以其高水平的遗传多样性和发育变通性适应着多变的盐环境。8]无论从DNA多态位点比率还是群体的基因多样性来看,异交植物锦鸡儿群体都具有比自交植物野大豆群体较高的水平。除了盐适应的野大豆群体外,一般来讲,锦鸡儿群体间的基因流要明显地大干野大豆的群体间的基因流。

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The striped catfish (Pangasianodon hypophthalmus) culture industry in the Mekong Delta in Vietnam has developed rapidly over the past decade. The culture industry now however, faces some significant challenges, especially related to climate change impacts notably from predicted extensive saltwater intrusion into many low topographical coastal provinces across the Mekong Delta. This problem highlights a need for development of culture stocks that can tolerate more saline culture environments as a response to expansion of saline water-intruded land. While a traditional artificial selection program can potentially address this need, understanding the genomic basis of salinity tolerance can assist development of more productive culture lines. The current study applied a transcriptomic approach using Ion PGM technology to generate expressed sequence tag (EST) resources from the intestine and swim bladder from striped catfish reared at a salinity level of 9 ppt which showed best growth performance. Total sequence data generated was 467.8 Mbp, consisting of 4,116,424 reads with an average length of 112 bp. De novo assembly was employed that generated 51,188 contigs, and allowed identification of 16,116 putative genes based on the GenBank non-redundant database. GO annotation, KEGG pathway mapping, and functional annotation of the EST sequences recovered with a wide diversity of biological functions and processes. In addition, more than 11,600 simple sequence repeats were also detected. This is the first comprehensive analysis of a striped catfish transcriptome, and provides a valuable genomic resource for future selective breeding programs and functional or evolutionary studies of genes that influence salinity tolerance in this important culture species.

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The purpose of this study is to demonstrate the appropriateness of “Japanese Manufacturing Management” (JMM) strategies in the Asian, ASEAN and Australasian automotive sectors. Secondly, the study assessed JMM as a prompt, effective and efficient global manufacturing management practice for automotive manufacturing companies to learn; benchmark for best practice; acquire product and process innovation, and enhance their capabilities and capacities. In this study, the philosophies, systems and tools that have been adopted in various automotive manufacturing assembly plants and their tier 1 suppliers in the three Regions were examined. A number of top to middle managers in these companies were located in Thailand, Indonesia, Malaysia, Singapore, Philippines, Viet Nam, and Australia and were interviewed by using a qualitative methodology. The results confirmed that the six pillars of JMM (culture change, quality at shop floor, consensus, incremental continual improvement, benchmarking, and backward-forward integration) are key enablers to success in adopting JMM in both automotive and other manufacturing sectors in the three Regions. The analysis and on-site interviews identified a number of recommendations that were validated by the automotive manufacturing company’s managers as the most functional JMM strategies.

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Aim To measure latitude-related body size variation in field-collected Paropsis atomaria Olivier (Coleoptera: Chrysomelidae) individuals and to conduct common-garden experiments to determine whether such variation is due to phenotypic plasticity or local adaptation. Location Four collection sites from the east coast of Australia were selected for our present field collections: Canberra (latitude 35°19' S), Bangalow (latitude 28°43' S), Beerburrum (latitude 26°58' S) and Lowmead (latitude 24°29' S). Museum specimens collected over the past 100 years and covering the same geographical area as the present field collections came from one state, one national and one private collection. Methods Body size (pronotum width) was measured for 118 field-collected beetles and 302 specimens from collections. We then reared larvae from the latitudinal extremes (Canberra and Lowmead) to determine whether the size cline was the result of phenotypic plasticity or evolved differences (= local adaptation) between sites. Results Beetles decreased in size with increasing latitude, representing a converse Bergmann cline. A decrease in developmental temperature produced larger adults for both Lowmead (low latitude) and Canberra (high latitude) individuals, and those from Lowmead were larger than those from Canberra when reared under identical conditions. Main conclusions The converse Bergmann cline in P. atomaria is likely to be the result of local adaptation to season length.

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Examined the social adaptation of 32 children in grades 3–6 with mild intellectual disability: 13 Ss were partially integrated into regular primary school classes and 19 Ss were full-time in separate classes. Sociometric status was assessed using best friend and play rating measures. Consistent with previous research, children with intellectual disability were less socially accepted than were a matched group of 32 children with no learning disabilities. Children in partially integrated classes received more play nominations than those in separate classes, but had no greater acceptance as a best friend. On teachers' reports, disabled children had higher levels of inappropriate social behaviours, but there was no significant difference in appropriate behaviours. Self-assessments by integrated children were more negative than those by children in separate classes, and their peer-relationship satisfaction was lower. Ratings by disabled children of their satisfaction with peer relationships were associated with ratings of appropriate social skills by themselves and their teachers, and with self-ratings of negative behaviour. The study confirmed that partial integration can have negative consequences for children with an intellectual disability.

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The use of the PC and Internet for placing telephone calls will present new opportunities to capture vast amounts of un-transcribed speech for a particular speaker. This paper investigates how to best exploit this data for speaker-dependent speech recognition. Supervised and unsupervised experiments in acoustic model and language model adaptation are presented. Using one hour of automatically transcribed speech per speaker with a word error rate of 36.0%, unsupervised adaptation resulted in an absolute gain of 6.3%, equivalent to 70% of the gain from the supervised case, with additional adaptation data likely to yield further improvements. LM adaptation experiments suggested that although there seems to be a small degree of speaker idiolect, adaptation to the speaker alone, without considering the topic of the conversation, is in itself unlikely to improve transcription accuracy.

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The term self-selected (i.e., individual or comfortable walking pace or speed) is commonly used in the literature (Frost, Dowling, Bar-Or, & Dyson, 1997; Jeng, Liao, Lai, & Hou, 1997; Wergel-Kolmert & Wohlfart, 1999; Maltais, Bar-Or, Pienynowski, & Galea, 2003; Browning & Kram, 2005; Browning, Baker, Herron, & Kram, 2006; Hills, Byrne, Wearing, & Armstrong, 2006) and is identified as the most efficient walking speed, with increased efficiency defined by lower oxygen uptake (VO^sub 2^) per unit mechanical work (Hoyt & Taylor, 1981; Taylor, Heglund, & Maloiy, 1982; Hreljac, 1993). [...] assessing individual and group differences in metabolic energy expenditure using oxygen uptake requires individuals to be comfortable with, and able to accommodate to, the equipment.