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排序方式: 共有1014条查询结果,搜索用时 31 毫秒
991.
Robin J. Boyd Thomas A. August Robert Cooke Mark Logie Francesca Mancini Gary D. Powney David B. Roy Katharine Turvey Nick J. B. Isaac 《Biological reviews of the Cambridge Philosophical Society》2023,98(5):1492-1508
Policy makers require high-level summaries of biodiversity change. However, deriving such summaries from raw biodiversity data is a complex process involving several intermediary stages. In this paper, we describe an operational workflow for generating annual estimates of species occupancy at national scales from raw species occurrence data, which can be used to construct a range of policy-relevant biodiversity indicators. We describe the workflow in detail: from data acquisition, data assessment and data manipulation, through modelling, model evaluation, application and dissemination. At each stage, we draw on our experience developing and applying the workflow for almost a decade to outline the challenges that analysts might face. These challenges span many areas of ecology, taxonomy, data science, computing and statistics. In our case, the principal output of the workflow is annual estimates of occupancy, with measures of uncertainty, for over 5000 species in each of several defined ‘regions’ (e.g. countries, protected areas, etc.) of the UK from 1970 to 2019. This data product corresponds closely to the notion of a species distribution Essential Biodiversity Variable (EBV). Throughout the paper, we highlight methodologies that might not be applicable outside of the UK and suggest alternatives. We also highlight areas where the workflow can be improved; in particular, methods are needed to mitigate and communicate the risk of bias arising from the lack of representativeness that is typical of biodiversity data. Finally, we revisit the ‘ideal’ and ‘minimal’ criteria for species distribution EBVs laid out in previous contributions and pose some outstanding questions that should be addressed as a matter of priority. Going forward, we hope that this paper acts as a template for research groups around the world seeking to develop similar data products. 相似文献
992.
Katharine Milton 《International journal of primatology》1998,19(3):513-548
Remarkably little attention has been focused on the physiological ecology of free-ranging primates. Yet without such information, it may prove difficult to advance our understanding of factors influencing the dietary behavior of wild primates much beyond its present state. Mantled howlers (Alouatta palliata) have been studied in terms of some features of physiological ecology. Results of this work have helped to clarify some factors influencing howler and other primate food choices in the natural environment and have called into question various assumptions about leaf-eating primates. For example, though howlers eat considerable foliage, they do not exhibit a lower than predicted basal metabolic rate, nor do available data suggest that secondary compounds strongly influence howler food selection. Comparison of howlers with members of the Colobinae reveals some differences in features of their respective energetic and digestive physiology and raises timely issues for future research. 相似文献
993.
Andrea Soriano-Redondo Marta Acácio Aldina M. A. Franco Bruno Herlander Martins Francisco Moreira Katharine Rogerson Inês Catry 《Ibis》2020,162(2):581-588
The development and miniaturization of GPS tracking devices has enabled a better understanding of migration phenology, but it can be challenging to identify where and when migration starts and ends, and researchers rely on multiple methods to infer it. Here, we use GPS tracks of 18 trans-Saharan migrant White Storks Ciconia ciconia to determine how the choice of method influences the estimation of migratory timing and discuss its implications. We evaluate and provide R code for the implementation of five alternative methods: spatial threshold, absolute displacement, spatio-temporal displacement, net squared displacement and change point analysis. Spatial threshold, absolute displacement and spatio-temporal displacement methods produce, in most cases, significantly different estimates of migration timing and duration as compared with net squared displacement and change point analysis. 相似文献
994.
Infection- and vaccine-induced antibody binding and neutralization of the B.1.351 SARS-CoV-2 variant
Venkata Viswanadh Edara Carson Norwood Katharine Floyd Lilin Lai Meredith E. Davis-Gardner William H. Hudson Grace Mantus Lindsay E. Nyhoff Max W. Adelman Rebecca Fineman Shivan Patel Rebecca Byram Dumingu Nipuni Gomes Garett Michael Hayatu Abdullahi Nour Beydoun Bernadine Panganiban Nina McNair Mehul S. Suthar 《Cell host & microbe》2021,29(4):516-521.e3
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995.
996.
Katharine Tyler 《Ethnos》2013,78(3):391-412
This article explores ethnographically the ‘village’ as a stage for the enactment and reproduction of a racialised set of white middle-class social and moral values. To do this I draw upon interview material with middle-class whites who live in a suburban ‘village’ on the border of rural Leicestershire and urban Leicester in England. I explore the way in which my co-conversationalists reflexively and imaginatively defend their area's ‘village’ identity through a discourse that ‘others’ its wealthy Asian residents. Although these raced others have achieved economic parity with the more affluent wealthy white middle-class residents, they are imagined to lack the ‘proper’ middle-class values of respectability and decorum, which are associated with the traditional white rhythms of English village life. 相似文献
997.
998.
Richa Rathore Katharine E. Caldwell Charles Schutt Caitlyn B. Brashears Bethany C. Prudner William R. Ehrhardt Cheuk Hong Leung Heather Lin Najat C. Daw Hannah C. Beird Abigail Giles Wei-Lien Wang Alexander J. Lazar John S.A. Chrisinger J. Andrew Livingston Brian A. Van Tine 《Cell reports》2021,34(4):108678
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999.
1000.