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排序方式: 共有174条查询结果,搜索用时 15 毫秒
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MJ Thompson J Toomre ER Anderson HM Antia G Berthomieu D Burtonclay SM Chitre J Christensen-Dalsgaard T Corbard M DeRosa CR Genovese DO Gough DA Haber JW Harvey F Hill R Howe SG Korzennik AG Kosovichev JW Leibacher FP Pijpers J Provost EJ Rhodes J Schou T Sekii PB Stark PR Wilson 《Science (New York, N.Y.)》1996,272(5266):1300-1305
Splitting of the sun's global oscillation frequencies by large-scale flows can be used to investigate how rotation varies with radius and latitude within the solar interior. The nearly uninterrupted observations by the Global Oscillation Network Group (GONG) yield oscillation power spectra with high duty cycles and high signal-to-noise ratios. Frequency splittings derived from GONG observations confirm that the variation of rotation rate with latitude seen at the surface carries through much of the convection zone, at the base of which is an adjustment layer leading to latitudinally independent rotation at greater depths. A distinctive shear layer just below the surface is discernible at low to mid-latitudes. 相似文献
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Javier Moreno Ignacio Palomo Javier Escalera Berta Martín-López Carlos Montes 《Landscape Ecology》2014,29(8):1407-1421
Integrating ecosystem services into ecosystem-based management (EBM) is currently one of the most relevant challenges for management. For that purpose, it is necessary to depict the relationships established between ecosystems and society considering the delivery, use and governance of ecosystem services. One effective way of doing so involves collaboration between researchers, who scientifically study the system, and managers, who have specific experience and technical knowledge. With this aim, we held two workshops in 2011 in the National Parks of Doñana and Sierra Nevada, Andalusia (Spain), with researchers and managers from the protected areas at different organizational levels: local, regional and national. Taking the participative mental model technique as an inspiration, we developed a tool that was used as a means to allow a holistic analysis of ecosystem services from an interdisciplinary and participative perspective. We found that participatory mental models, help integrating ecosystem services into EBM as it includes stakeholders’ proposals and knowledge. For the implementation of ecosystem services for management, we discuss the necessity of navigating a process that requires considerable changes, not only in using new concepts such as ecosystem services, but also in the management structures that govern the services. This process would require closer interaction between citizens, researchers and managers, and the creation of new participation spaces that include ecosystem service beneficiaries located beyond protected areas. 相似文献
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Retrospective analysis of records, from July 1987 to June 1991, of 1140 inspections of slaughtered pigs from 154 swine herds in the Pig Health Monitoring Scheme of South Australia was conducted to evaluate patterns of variation in the prevalence and severity of skin lesions typical of sarcoptic mange. An increase in the severity of sarcoptic mange in winter and spring was observed. There was a substantial reduction in the severity of mange over the period of monitoring. These observations support the role of monitoring at slaughter in the management of endemic disease. They provide some basis for refining control programs for mange to improve cost-effectiveness. 相似文献
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A cross-sectional study to show Eperythrozoon ovis infection is prevalent in Western Australian sheep farms 总被引:4,自引:0,他引:4
A serological survey and risk factor study was conducted to estimate the prevalence of Eperythrozoon ovis infection in Western Australian weaner sheep, the prevalence of farms with infected sheep, and to identify factors affecting initiation and maintenance of infection on the farm. The study was conducted on 91 farms, purposively chosen from 41 randomly selected regional shires stratified by sheep number and rainfall zones. Twenty sheep were selected systematically from a mixed-sex flock on each farm and tested for serum antibody to E ovis using an enzyme-linked immunosorbent assay. Information on putative risk factors was collected using an interview questionnaire. Antibody to E ovis was detected in 4.5% of sheep on 47% of the farms sampled. The prevalence of E ovis infection in sheep was estimated at the 95% confidence level to be between 3.6 and 5.5%, and the prevalence of farms with infected sheep was estimated to be between 37.5 and 56.5%. Most farms with serological evidence of infection occurred in the Great Southern agricultural region (79.5%), south-east of Perth through to Albany (latitude 32 to 34 degrees S, longitude 116 to 120 degrees E), and in the Northern region (12.8%) surrounding Geraldton (latitude 29 degrees S, longitude 114 degrees E). There were significantly more farms (P less than 0.05) with evidence of infection in the Great Southern region compared to the Central region between Geraldton and Perth, and on farms in the region south compared to north of latitude 32 degrees S. None of the putative risk factors examined in the questionnaire were associated with serological evidence of infection on the farm.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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