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31.
采用病原分离与鉴定、人工感染试验等方法,在对养殖牙鲆病例进行发病情况、病理变化特征检验的基础上,进行病原学检验。结果表明,此病例属于由弧菌属(VibrioPacini1854)细菌引起的败血感染症。经对12株纯培养菌(HQ010712-1—HQ010712-12)进行形态特征、理化特性等表观分类学指征的检验,选择代表菌株(HQ010712-1株)进行16S rRNA基因的测定与系统发育学分析等,判定为弧菌属的一个新种。将HQ010712-1株送中国典型培养物保藏中心(CCTCC)进行了复核鉴定与分类定名,依据分离地定名为秦皇岛弧菌(Vibrioqinhuangdaorasp.nov.);参考菌株为HQ010712-1。  相似文献   
32.
The fragments of 350 bp in 28S rRNA from the closely related monogenea of trematoda, Neobenedenia girellae and N. melleni are obtained by polymerase chain reaction (PCR) amplified using a couple of special primers and then sequenced. The results show that the comparison of 28S rRNA sequences, with only a base varying in 337 bp accounting for 0.3% genetic difference, from the relative species N. girellae and N. melleni parasitized on the different fishes in different farms displays that they possess a very high genetic similarity of 99.7%, higher than that of 99.41% for the single species N. melleni sampled in different areas, and the intraspecific divergence of N.melleni is 0.59%. Meanwhile, the interspecific differences between the two Neobenedenia and three Benedenia (i.e., B. lutjani, B. rohdei and B. seriolae) range from 2.08% tol 1.73%. In addition, UPGMA and MP molecular phylogenetic trees are constructed and proved to be consistent with each other. Though the morphological characteristics and the results of genetic diversity for the two Neobenedenia show a high similarity, whether they belong to a single species or not are still undefined, and the more genes of them should be further investigated, in combination with the systematical and detailed morphological study.  相似文献   
33.
全面、现势的土地利用基础图件是一个国家摸清其土地资源家底,进行土地资源合理利用、规划和科学管理的基础和前提条件。本文从数据源、处理手段与采用的技术方法对土地利用基础图件更新的技术体系进行了研究,基于图件更新技术流程的三个主要环节对图件更新方法进行了系统分析和分类总结,继而提出了一套集RS/GIS/GPS技术于一体的图件更新技术方法与流程;同时依托具有自主知识产权的遥感数据处理平台CASM Im-ageInfo,将整个作业流程一体化,构建了适合我国具体国情的实用和可操作性强的土地利用基础图件更新软件系统,实现了土地利用基础图件的快速更新。  相似文献   
34.
利用了SuperMap Objects组件,构建了C/S模式的河南理工大学校园导航系统,实现了信息查询、路径导航、办事指南、地图与数据编辑、数据输出、用户管理及三维虚拟校园导航等功能,并提供了与现有校园系统集成的接口.  相似文献   
35.
随着3S技术的不断发展,客户要求的不断提高,原始的服务方式已经不能满足客户对多元信息获取的需要,在这样的背景之下,哈尔滨市用地查询分析系统应运而生,它的成功研制有效解决了客户需求,并对其他项目数据整合的方式与方法提供了有益的解决方案。  相似文献   
36.
An updated analysis of geothermal data from the highland area of eastern Brazil has been carried out and the characteristics of regional variations in geothermal gradients and heat flow examined. The database employed includes results of geothermal measurements at 45 localities. The results indicate that the Salvador craton and the adjacent metamorphic fold belts northeastern parts of the study area are characterized by geothermal gradients in the range of 6–17°C/km. The estimated heat flow values fall in the range of 28–53 mW/m2, with low values in the cratonic area relative to the fold belts. On the other hand, the São Francisco craton and the intracratonic São Francisco sedimentary basin in the southwestern parts are characterized by relatively higher gradient values, in the range of 14–42°C/km, with the corresponding heat flow values falling in the range of 36–89 mW/m2. Maps of regional variations indicate that high heat flow anomaly in the São Francisco craton is limited to areas of sedimentary cover, to the west of the Espinhaço mountain belt. Crustal thermal models have been developed to examine the implications of the observed intracratonic variations in heat flow. The thermal models take into consideration variation of thermal conductivity with temperature as well as change of radiogenic heat generation with depth. Vertical distributions of seismic velocities were used in obtaining estimates of radiogenic heat production in crustal layers. Crustal temperatures are calculated based on a procedure that makes simultaneous use of the Kirchoff and Generalized Integral Transforms, providing thereby analytical solutions in 2D and 3D geometry. The results point to temperature variations of up to 300°C at the Moho depth, between the northern Salvador and southern São Francisco cratons. There are indications that differences in rheological properties, related to thermal field, are responsible for the contrasting styles of deformation patterns in the adjacent metamorphic fold belts.  相似文献   
37.
Intrusive features of varying size can be interpreted from the aeromagnetic map of the Xanthi area in N. Greece.The Xanthi pluton, which outcrops north of the city of Xanthi, seems to have the shape of a truncated pyramid. This feature has relatively large areal extent and reaches an approximate depth of 7 km. Another, relatively large magnetic body is buried under the sediments at the estuary of the Nestos River.3-D models of several smaller intrusions were constructed and the produced effect was compared to the observed. Some of these intrusions seem to be detached branches of the large Xanthi pluton.The basement in the outer part of the basin of the Nestos River seems to be buried at about 4 km depth. This figure is obtained by the Multiple Source Werner Deconvolution estimates and it is in agreement with the results of former geophysical studies and deep industrial boreholes.A 3-D model of the Xanthi-Komotini basin suggests that this basin is about 0.4 km deep at its southern part. The depth at its northern boundary is about 1.8 km while the boundary itself is formed by the large Kavala-Xanthi-Komotini fault.The Tertiary basin of the Nestos River and the observed magmatism are consistent with the idea of an older extensional tectonic regime in the area.  相似文献   
38.
The existence of a suspected geological fault has been confirmed using Solid State Nuclear Track Detectors (SSNTDs) by measuring radon concentration variations in the upper soil above its inferred position. The results obtained prompted us to increase the natural radon signal in the soil, using an additional radon source; this enhancement technique, has been experimentally checked with SSNTD detectors.On leave from Faculté des Sciences, Laboratoire des D.S.T.N. Université de Dakar, Dakar-Fann, Sénégal  相似文献   
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ABSTRACT. This study examines altitudinal residential segregation by race in 146 cities in the U.S. South. It begins by embedding the topic in recent theorizations of the social construction of nature, the geography of race, and environmental justice. Second, it focuses on how housing markets, particularly in the South, tend to segregate minorities in low‐lying, flood‐prone, and amenity‐poor segments of urban areas. It tests empirically the hypothesis that blacks are disproportionately concentrated in lower‐altitude areas using gis to correlate race and elevation by digital elevation‐model block group within each city in 1990 and 2000. The statistical results confirm the suspected trend. A map of coefficients indicates strong positive associations in cities in the interior South‐where the hypothesis is confirmed‐and an inverse relationship near the coast, where whites dominate higher‐valued coastal properties. Selected city case studies demonstrate these relationships connecting the broad dynamics of racial segregation to the particularities of individual places.  相似文献   
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