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61.
To identify potential antivirals against BTV, we have developed, optimized and validated three assays presented here. The CPE-based assay was the first assay developed to evaluate whether a compound showed any antiviral efficacy and have been used to screen large compound library. Meanwhile, cytotoxicity of antivirals could also be evaluated using the CPE-based assay. The dose-response assay was designed to determine the range of efficacy for the selected antiviral, i.e. 50% inhibitory concentration (IC50) or effective concentration (EC50), as well as its range of cytotoxicity (CC50). The ToA assay was employed for the initial MoA study to determine the underlying mechanism of the novel antivirals during BTV viral lifecycle or the possible effect on host cellular machinery. These assays are vital for the evaluation of antiviral efficacy in cell culture system, and have been used for our recent researches leading to the identification of a number of novel antivirals against BTV. 相似文献
62.
The complicated task of measuring environmental sustainability has often led to comparative evaluations of national performance using ranking lists and generic policy targets. In this paper, a set of national environmental indicators is determined through the deployment of a five-stage methodology, which includes the use of focus group research and formation of an expert team to guide the process, selection of an initial pool of pre-existing indicators, establishment of criteria to guide the selection process, and setting of appropriate policy or trend-based targets given the nation-specific context. The nations of Iceland and Norway are used as case studies to demonstrate an effective means of communicating indicator outcomes over time. National performance is first evaluated on an indicator-by-indicator basis and then summarised overall through a system of traffic lights and radar charts for trend and target-based indicators respectively. Via this analytical process, it also becomes clear that data shortages partially constrain the extent to which a nation’s environmental sustainability performance can be deciphered. Improved data collection is necessary connected to the measurement of several environmental issues on a national scale, particularly the sustainability of fisheries, soil erosion and biodiversity. 相似文献
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64.
Heihe River is the second largest inland river in northwest China which flows through Qinghai Province, Gansu Province and Inner Mongolia Autonomous Region. Because of the rapid development of social economy, the sharp increase of water utilization in the middle reaches and the aggravation of contradiction of supply and demand on water resources, the water to the lower reaches decreases and the ecological environment deteriorates constantly. According to the severe situation of ecology system depravation in Heihe River basin, Chinese government decided to invest 2.35 billion RMB to carry out 3 years ecological management in Heihe River basin from August in 2001. After 3 years ecological management, the depravation of ecological environment is controlled effectively. This paper researches the ecological management engineering in the upper reaches of Heihe River and evaluates the effect of the ecological management engineering. The methods of field sampling and measuring are used to obtain the index indicating the ecology change in the upper reaches of Heihe River in 2006. The effects of fencing grassland, fencing natural forest, and artificial afforestation to the ecology are evaluated. The result suggests that: Firstly, in fencing grassland area, the yield of grass had increased by 42–113%, average height of the grass had increased by 60–100%, and the degree of coverage had increased by 67–100%. Secondly, in fencing natural forests area, the degree of coverage had increased by 15–33%, the shade density had increased by 50–100%, average height had increased by 80–125%, and the crown size had increased by 63–186%. Thirdly, the growth increment of the trees in artificial afforestation area is bigger than that outside artificial afforestation area. In conclusion, ecological management leads to obvious ecological effect in the upper reaches of Heihe River. 相似文献
65.
野生杜鹃花迁地保护适应性评价 总被引:11,自引:0,他引:11
通过半定量评价法 ,对四川都江堰中国杜鹃园内引种的来自各地的、分属杜鹃属 7亚属、 35组 (或亚组 )的 131种杜鹃花的适应能力和对各生态因子的耐性进行了研究。结果表明 :很适应的占 2 5 % ,适应的占 5 2 % ,欠适应的占 15 % ,不适应的占 8%。常绿杜鹃亚属、杜鹃亚属的多数种类或主要分布于常绿阔叶林、常绿落叶阔叶混交林、针阔混交林、寒温性针叶林中的杜鹃类群 ,很适应或适应中国杜鹃园的生境 ;而主要分布于高山灌丛、高山草甸上和低海拔松 -栎林中的杜鹃类群 ,表现为欠适应或不适应当地的生境条件。从上述证据中我们认为中国杜鹃园地址的选择基本上满足了杜鹃花的迁地保护需要。 相似文献
66.
水稻耐冷性鉴定评价方法 总被引:47,自引:7,他引:40
水稻耐冷性是我国东北和西南高海拔地区、日本、韩国和朝鲜等国水稻育种的重要研究目标,至今许多学者对水稻耐冷性进行了广泛的研究,并且目前所采用的耐冷性鉴定评价方法已基本成熟,但国内还没有对其进行技术规范化.本文汇总了国内外至今所采用的水稻耐冷性鉴定方法和耐冷指标及分级标准等,将为水稻耐冷性种质资源鉴定和育种以及我国水稻耐冷性鉴定评价技术规范的制定提供参考依据. 相似文献
67.
吉林省生态系统服务价值评估 总被引:2,自引:0,他引:2
吉林省生态系统效益总价值为1.74×1010USD·a-1,占全国总价值的3.6%。其中,森林生态系统效益的总价值占全省的15%,草原生态系统、沼泽湿地生态系统、河流湖泊生态系统以及耕地生态系统分别占1.6%、51.3%、29%和3.1%。其中,面积比重占到90%以上的的森林、草地和耕地生态系统效益价值占全省的20%左右,面积比重仅占6.2%的河流湖泊及沼泽湿地则占全省的80%之多;沼泽湿地的生态系统效益价值所占比例最高,草地最低;十七种生态系统效益中,生态系统的生态效益价值为1.55×1010USD·a-1,占总价值的88.9%,远高于其经济效益和社会效益的价值;在地区分布上,吉林省各地区生态系统效益价值排序为白城﹥延边州﹥松源﹥长春﹥吉林﹥通化﹥四平﹥白山﹥辽源。 相似文献
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69.
水稻耐盐碱鉴定标准评价及建议与展望 总被引:7,自引:0,他引:7
杨福 《植物遗传资源学报》2011,12(4):625-628
对国内外水稻耐盐碱鉴定评价标准进行了评述,指出目前采用的评价标准存在着对盐碱害判断不够全面、准确的问题,只适用对水稻进行生物耐盐力的鉴定,而不适合对水稻的农业耐盐力进行鉴定;提出了对水稻耐盐碱鉴定的标准品种、方法、鉴定胁迫浓度等进行改进的建议,强调对水稻进行全生育期的耐盐碱性鉴定。 相似文献
70.
基于主成分分析的优质鸡肉质评价研究 总被引:4,自引:0,他引:4
优质鸡的内涵在于肉质,但目前肉质的评定还没有一个统一的标准.本研究通过对大恒优质肉鸡5个新品系共150个个体和与肉质有密切联系的8个理化指标进行主成分分析,8个原始指标被综合成了3个独立的新指标:主成分1,肉质因子;主成分2,口感和风味因子;主成分3,嫩度因子,筛选出的3个新指标包含了原有指标的大部分信息,累积贡献率达到88.42%.通过比较3个指标的综合得分大小对10个群体的优质鸡肉质进行了评价,结果表明:S01系肉质最好,S03系次之,而D99系肉质最差,而且母鸡肉质均优于公鸡.同时利用第一主成分制定了优质鸡的肉质指数. 相似文献