994 resultados para Global VAR


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The composition of the leaf oils from seven populations of J. sabina L., one population of Juniperus sabina var. arenaria (E. H. Wilson) Farjon were examined for their geographic variation. In addition, the leaf oils of J. chinensis L. and J. davurica Pall. were compared to J. sabina. Juniperus sabina var. arenarla, the sand loving juniper, oil was found to be very similar to that of J. davurica, Mongolia, and J. sabina, on sand dunes in Mongolia. This suggests that J. sabina var. arenaria might be conspecific with J. davurica. Farjon's move (2001) of J. sabina var. arenaria out of J. chinensis is supported. Considerable differentiation was found in populations of J. sabina from the Iberian peninsula. Cedrol, citronellol, safrole, trans-sabinyl acetate, terpinen-4-ol and beta-thujone were found to be polymorphic in several populations.

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具有全局平移优先属性的主动轮廓更适于目标跟踪。演化轮廓具有的全局平移优先性可以理解为沿轮廓的速度场具有相等的倾向。根据此思想,通过定义在曲线扰动集合上的新内积空间导出了一种简单,具有平移优先的梯度流。新的内积空间由于是通过向H0主动轮廓对应的內积空间引入曲线扰动的方差获得,所以此主动轮廓称为方差主动轮廓。方差主动轮廓是将H0主动轮廓与其对应的平均梯度流通过加权求和获得,而H1主动轮廓则是通过H0主动轮廓与特定类型的核函数进行卷积得到。因此方差主动轮廓实现时更简单和快速。最后给出了H0,H1和方差主动轮廓在频域与时域的分析。

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通过对甘蓝进行品种差异、亚细胞分析、根际分泌物提取污染土壤中的铊、营养元素添加以及野外甘蓝样品采集分析,结合地球化学理论。分析了甘蓝对铊吸收富集的机理,并得出以下几点结论: (1) 甘蓝叶、根及茎对铊的吸收存在着明显差异,表明在面临土壤铊胁迫时,叶是铊的主要储存部位,而根和茎主要起到了转运作用。甘蓝中铊含量的升高导致了对钙和镁吸收能力的提高。不同品种甘蓝之间的吸收能力差别不大,通过选择种植对铊吸收能力小的甘蓝来控制铊的食物链危害是不可行的。此外,还应该避免在高铊土壤地区种植甘蓝。 (2) 高达92%的铊存在于甘蓝叶细胞液组分中,表明细胞液组分是铊在甘蓝叶细胞中的一个重要储存部位。但是在不同品种甘蓝叶中,铊的亚细胞分布形态没有显著差异,在甘蓝面对铊胁迫时,其叶细胞器组分中铊含量始终维持很低的含量。甘蓝对铊的解毒机制很可能就是通过在细胞内的区隔化作用(compartmentalization),把进入体内的铊结合到细胞液组分以及细胞壁上,从而减少了铊对重要细胞器官的损伤。铊在甘蓝叶各亚细胞组分中的分配与常量元素存在一定的关系。在甘蓝叶细胞内,Tl+往细胞液组分中的传输很有可能是通过Na+/K+/2Cl–联合传输机制、Ca2+活化的钾离子通道以及一些需Mg2+或Mn2+的K+活化酶完成的。需要Mn2+参与的K+活化酶可能对于铊往细胞器中的转移起到了主导作用。在细胞壁中,很可能Ca2+活化的K+通道或者是某些特定的需要Mn2+的K+活化酶对铊的迁移或固定起了影响作用。 (3) 随着氮、磷、钾营养元素的加入,甘蓝地上部的生物量有一定程度的上升。影响主次因素依次均为氮>磷>钾。随着氮、磷、钾营养元素的加入,甘蓝地上部和地下部的铊含量并没有上升,而是有一定程度的下降。甘蓝地上部中铊含量的影响主次因素依次为磷>氮>钾,甘蓝地下部中铊含量的影响主次因素依次为氮>磷>钾。氮、磷、钾营养元素的加入都提高了甘蓝对铊的吸收量。甘蓝对铊吸收量的影响主次因素依次均为氮>磷>钾。因此我们认为,氮,磷,钾的加入显著提高了甘蓝生物量和铊的吸收量,但是随之而来的生物稀释效应,导致了甘蓝地上部和地下部含量的降低。运用铊累积量来判断营养元素对甘蓝吸收铊的影响更为客观和可靠。 (4) 通过对比蒸馏水和根际分泌物提取液对污染土壤中铊的提取能力,发现甘蓝根际分泌物提取液(root exudates)对污染土壤中的铊具有明显的活化作用。提取液的pH和土壤铊的提取率存在一定的正相关(R2=0.1659),也就是说提取液的pH与其对污染土壤中铊的提取能力成正比。但是甘蓝体内各部分铊含量与其根际分泌物提取液对土壤铊的提取率没有任何关系,表明大量的植物非必需元素铊进入甘蓝后,并没有对其根际分泌物的产生任何影响。土壤pH越高,生长的甘蓝的根际分泌物提取液对土壤提取率就越高,甘蓝分泌物提取液对铊的提取率升高可以补偿由于土壤pH升高而造成的水溶态存在的铊减少。 (5) 铊在甘蓝叶片和叶柄中的分布状况为老叶叶片>新叶叶片>老叶叶柄>新叶叶柄,表明叶柄也是运输铊的一个重要器官。但是叶柄对铊的转运能力并没有茎那么强烈,而叶片才是甘蓝中最主要的铊储存部位。铊在根、茎、老叶和新叶中亚细胞的分布均为细胞液>>细胞壁>细胞器,这和前期室内温室培养甘蓝叶片中的分布结果是一致的。根据植物采矿经济理论的计算结果,很显然甘蓝可以成为土壤铊污染的植物修复和采矿的备选对象。

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The inherent instability of metabolite production in plant cell culture-based bioprocessing is a major problem hindering its commercialization. To understand the extent and causes of this instability, this study was aimed at understanding the variability of anthocyanin accumulation during long-term subcultures, as well as within subculture batches, in Vitis vinifera cell cultures. Therefore, four cell line suspensions of Vitis vinitera L. var. Gamay Freaux, A, B, C and D, originated from the same callus by cell-aggregate cloning, were established with starting anthocyanin contents of 2.73 +/- 0.15, 1.45 +/- 0.04, 0.77 +/- 0.024 and 0.27 +/- 0.04 CV (Color Value)/g-FCW (fresh cell weight), respectively. During weekly subculturing of 33 batches over 8 months, the anthocyanin biosynthetic capacity was gradually lost at various rates, for all four cell lines, regardless of the significant difference in the starting anthocyanin content. Contrary to this general trend, a significant fluctuation in the anthocyanin content was observed, but with an irregular cyclic pattern. The variabilities in the anthocyanin content between the subcultures for the 33 batches, as represented by the variation coefficient (VC), were 58, 57, 54, and 84% for V vinifera cell lines A, B, C and D, respectively. Within one subculture, the VCs from 12 replicate flasks for each of 12 independent subcultures were averaged, and found to be 9.7%, ranging from 4 to 17%. High- and low-producing cell lines, VV05 and VV06, with 1.8-fold differences in their basal anthocyanin contents, exhibited different inducibilities to L-phenylalanine feeding, methyl jasmonate and light irradiation. The low-producing cell line, showed greater potential in enhanced the anthocyanin production.

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Taxonomia e nomenclatura. O gênero Schizolobium. Distribuição geográfica. Características da espécie. Usos. Reprodução sexuada. Germinação. Produção de mudas. Propagação assexuada. Preparo do solo e plantio. Espaçamento. Adubação. Controle de pragas e doenças. Controle de plantas invasoras. Silvicultura e manejo. Crescimento. Utilização em sistemas agroflorestais. Plantio com cultivos perenes. SAFs a partir de regeneração natural de paricá. Uso de leguminosas em sistemas agroflorestais com paricá. Orçamento para produção de 10.000 mudas de paricá.

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As cultivares utilizadas pelos produtores acreanos são pouco adaptadas às condições climáticas locais. Novas cultivares de repolho adaptadas às temperaturas elevadas e resistentes às principais doenças, têm sido lançadas no mercado pelos órgãos de pesquisa pública e firmas privadas. Como existem poucas informações no Estado em relação ao comportamento dessas cultivares, foi iniciado um trabalho de introdução e avaliação, com o objetivo de identificar germoplasmas adaptados às condições edafoclimáticas do Acre.

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Pesquisa que busca caracterizar as emissões de inflorescências do coqueiro anão por ano.

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Estabelece as percentagens dos componentes de frutos de coqueiro anao, nos pontos de colheita para agua de coco, seis meses e sete meses, e para albumen solido, doze meses.

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Traditionally, language speakers are categorised as mono-lingual, bilingual, or multilingual. It is traditionally assumed in English language education that the ‘lingual’ is something that can be ‘fixed’ in form, written down to be learnt, and taught. Accordingly, the ‘mono’-lingual will have a ‘fixed’ linguistic form. Such a ‘form’ differs according to a number of criteria or influences including region or ‘type’ of English (for example, World Englishes) but is nevertheless assumed to be a ‘form’. ‘Mono-lingualism’ is defined and believed, traditionally, to be ‘speaking one language’; wherever that language is; or whatever that language may be. In this chapter, grounded in an individual subjective philosophy of language, we question this traditional definition. Viewing language from the philosophical perspectives such as those of Bakhtin and Voloshinov, we argue that the prominence of ‘context’ and ‘consciousness’ in language means that to ‘fix’ the form of a language goes against the very spirit of how it is formed and used. We thus challenge the categorisation of ‘mono’-lingualism; proposing that such a categorisation is actually a category error, or a case ‘in which a property is ascribed to a thing that could not possibly have that property’ (Restivo, 2013, p. 175), in this case the property of ‘mono’. Using this proposition as a starting point, we suggest that more time be devoted to language in its context and as per its genuine use as a vehicle for consciousness. We theorise this can be done through a ‘literacy’ based approach which fronts the context of language use rather than the language itself. We outline how we envision this working for teachers, students and materials developers of English Language Education materials in a global setting. To do this we consider Scotland’s Curriculum for Excellence as an exemplar to promote conscious language use in context.

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Technological developments over the last thirty years increasingly shaped the means by which we recruit, select and appraise employees. Today, technology supports more flexible and geographically dispersed working modes: From teleworkers, to virtual workers, to e-interns (also known as virtual interns). The current article describes how developments in e-HRM and changes in employment forms contribute to the development and increasing popularity of e-internships (better known as virtual internships) amongst small and medium-sized enterprises. In this paper, we reflect on the rise of e-internships across different countries and relate this to e-HRM and technological advances. We explore the opportunities and challenges. These include developing effective global talent and knowledge management practices, managing diversity as well as intellectual and social capital. We furthermore link the employment of e-internship practices to strategic organizational goals and learning. In the final section, we also critically reflect on the high investment required for e-internships to succeed. The discussion on e-internships is set in the literature on e-HRM, virtual teams and knowledge management, which is furthermore supported by interviews conducted with e-interns or internship managers. Keywords: e-internships, virtual internships, computer-mediated communication