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91.
B. Koetz F. Morsdorf S. van der Linden T. Curt B. Allgwer 《Forest Ecology and Management》2008,256(3):263
Forest fire management practices are highly dependent on the proper monitoring of the spatial distribution of the natural and man-made fuel complexes at landscape level. Spatial patterns of fuel types as well as the three-dimensional structure and state of the vegetation are essential for the assessment and prediction of forest fire risk and fire behaviour. A combination of the two remote sensing systems, imaging spectrometry and light detection and ranging (LiDAR), is well suited to map fuel types and properties, especially within the complex wildland–urban interface. LiDAR observations sample the spatial information dimension providing explicit geometric information about the structure of the Earth's surface and super-imposed objects. Imaging spectrometry on the other hand samples the spectral dimension, which is sensitive for discrimination of surface types. As a non-parametric classifier support vector machines (SVM) are particularly well adapted to classify data of high dimensionality and from multiple sources as proposed in this work. The presented approach achieves an improved land cover mapping adapted to forest fire management needs. The map is based on a single SVM classifier combining the spectral and spatial information dimensions provided by imaging spectrometry and LiDAR. 相似文献
92.
Jun Ohnishi Toshio Kitamura Fumihiro Terami Ken-ichiro Honda 《Journal of General Plant Pathology》2009,75(2):131-139
We studied the presence of a potential transmission barrier that blocks Tomato yellow leaf curl virus in the nonvector greenhouse whitefly, Trialeurodes vaporariorum. Because T. vaporariorum can ingest and retain the virus after acquisition feeding on an infected plant, comparable to the vector whitefly Bemisia tabaci, circumstance evidence suggested that a transmission barrier presents at location(s) where the virus moves from the digestive
tract lumen to the hemolymph. To provide direct evidence for the site of a transmission barrier in the nonvector insect, we
compared the accumulation levels and localization of the virus between the two species of whiteflies. Quantitative real-time
and conventional PCR analysis showed that accumulation of the virus during acquisition feeding and retention after a short
acquisition period were indistinguishable between the two species, but the circulation of the virus within the whiteflies
differed significantly between the species. In an immunofluorescence analysis using an antibody specific to the coat protein
of the virus, the virus was restricted to the luminal surface of the midgut epithelial cells and did not enter their cytoplasm
or that of the salivary glands in T. vaporariorum. In contrast, the virus was localized within the cytoplasm of the midgut epithelial cells and in the paired salivary glands
of B. tabaci adults. This direct evidence shows that a selective transmission barrier at the luminal membrane surface of midgut epithelial
cells in the nonvector whitefly blocks entrance of the virus into the midgut epithelial cells, resulting in incompetence as
a vector of the virus. 相似文献
93.
甘蓝型油菜依赖焦磷酸的磷酸果糖激酶(PFK)基因片段克隆及hpRNAi载体构建 总被引:4,自引:0,他引:4
依赖焦磷酸的磷酸果糖激酶(PFK)是糖酵解途径的关键酶。本研究首先构建带有种子特异性napin启动子和Nos终止子的植物表达载体2300-nap及带有组成型35S启动子和Nos终止子的植物表达载体2300-35S;然后用PCR法从甘蓝型油菜(BrassicanapusL.)中油119总基因组中扩增出依赖焦磷酸的磷酸果糖激酶(PFK)基因片段,再以扩增出的PFK基因片段作模板设计引物扩增出一个相应的小片段。将两个PFK基因片段反向连接,插入到植物表达载体2300-nap的napin启动子和nos终止子之间,植物表达载体2300-35S的35S启动子和nos终止子之间,分别构建成可转录表达出发夹RNA(hairpinRNA,hpRNA)结构的种子特异型和组成型油菜RNA干扰载体,为今后油菜利用RNA干扰(RNAi)提高含油量的基因工程研究奠定了基础。 相似文献
94.
本文扼要地介绍了决策支持系统(DSS)在解决半结构化问题决策中的作用,论述了它在农业上应用的必要性和可能性,文中举例简介了农场适度经营规模的DSS,以展示其建立过程,和作者在1987年建立的饲料配方DSS。 相似文献
95.
96.
蛋白质功能的预测是当前生物信息技术的一个重要研究方向,它广泛应用于分析新发现蛋白质的功能及人工合成的蛋白质功能。利用酵母蛋白相互作用数据,首先针对传统的基于支持向量机和基于邻近投票法的功能预测法分析了它们各自的优劣性,然后研究出结合2种预测方法的优势的NC-SVM法对酵母蛋白的功能进行预测,采用科学的评价方法,通过反复试验并对结果进行分析,发现这种新方法的预测结果优于单独使用前2种,而且具有一定的稳定性。 相似文献
97.
98.
Reallocation of regular size parcels is accepted as the core of land consolidation. For fast and efficient progress in projects, usage of computer technology has been essential.In this case study, a Spatial Decision Support System (SDSS)-based land reallocation model was developed to provide reallocating newly created regular size parcels to landowners in land consolidation projects. Reallocation results of the SDSS-based land reallocation model and conventional land reallocation models are compared. Surveys were conducted with the landowners in order to obtain their opinions of the land reallocation results. The purpose of the survey study was to determine which of the two land reallocation models they preferred. 66.1% (39 people) of the interviewed landowners stated that they were pleased with their land reallocation on the basis of the conventional land reallocation model. This compares with 89.9% (53 people) of the landowners who expressed that they were pleased with the outcome of the SDSS-based model. According to the results, the SDSS-based land reallocation model was more preferred by landowners. 相似文献
99.
应用Gateway技术构建水稻OsDAD1基因的RNA干涉载体 总被引:7,自引:0,他引:7
近年来,RNA干涉广泛应用于植物基因功能研究.Gateway技术是通过采用多重载体高效构建目标基因及任何DNA片段克隆和表达载体的研究平台,该技术以λ噬菌体的位点特异性重组体系为基础,两端具有重组位点的DNA片段或目标基因可以非常容易地被重组克隆到含同源重组位点的载体上.这种以重组为基础的克隆体系目前已被广泛应用于分子生物学中来分析基因的功能.本文应用Gateway技术体系替代传统载体构建方法,构建了水稻基因OsDAD1的RNA干涉载体,从而证明了Gateway技术的可行性. 相似文献
100.