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101.
102.
Adjuvant disease-prevention with complete Freund's adjuvant and with mineral oil alone 总被引:1,自引:0,他引:1
103.
Ouimette Andrew P. Ollinger Scott V. Lepine Lucie C. Stephens Ryan B. Rowe Rebecca J. Vadeboncoeur Matthew A. Tumber-Davila Shersingh J. Hobbie Erik A. 《Ecosystems》2020,23(4):715-729
Ecosystems - Carbon (C) fluxes among different components of plant growth are important to forest ecosystem C cycling and are strongly influenced by species composition and resource availability.... 相似文献
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Claire S. Teitelbaum Caroline R. Amoroso Shan Huang T. Jonathan Davies Julie Rushmore John M. Drake Patrick R. Stephens James E. Byers Ania A. Majewska Charles L. Nunn 《Ecography》2020,43(9):1316-1328
Understanding the drivers of biodiversity is important for forecasting changes in the distribution of life on earth. However, most studies of biodiversity are limited by uneven sampling effort, with some regions or taxa better sampled than others. Numerous methods have been developed to account for differences in sampling effort, but most methods were developed for systematic surveys in which all study units are sampled using the same design and assemblages are sampled randomly. Databases compiled from multiple sources, such as from the literature, often violate these assumptions because they are composed of studies that vary widely in their goals and methods. Here, we compared the performance of several popular methods for estimating parasite diversity based on a large and widely used parasite database, the Global Mammal Parasite Database (GMPD). We created artificial datasets of host–parasite interactions based on the structure of the GMPD, then used these datasets to evaluate which methods best control for differential sampling effort. We evaluated the precision and bias of seven methods, including species accumulation and nonparametric diversity estimators, compared to analyzing the raw data without controlling for sampling variation. We find that nonparametric estimators, and particularly the Chao2 and second-order jackknife estimators, perform better than other methods. However, these estimators still perform poorly relative to systematic sampling, and effect sizes should be interpreted with caution because they tend to be lower than actual effect sizes. Overall, these estimators are more effective in comparative studies than for producing true estimates of diversity. We make recommendations for future sampling strategies and statistical methods that would improve estimates of global parasite diversity. 相似文献
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Andrew D. Stephens Cory W. Quammen Binny Chang Julian Haase Russell M. Taylor II Kerry Bloom 《Molecular biology of the cell》2013,24(24):3909-3919
In mitosis, the pericentromere is organized into a spring composed of cohesin, condensin, and a rosette of intramolecular chromatin loops. Cohesin and condensin are enriched in the pericentromere, with spatially distinct patterns of localization. Using model convolution of computer simulations, we deduce the mechanistic consequences of their spatial segregation. Condensin lies proximal to the spindle axis, whereas cohesin is radially displaced from condensin and the interpolar microtubules. The histone deacetylase Sir2 is responsible for the axial position of condensin, while the radial displacement of chromatin loops dictates the position of cohesin. The heterogeneity in distribution of condensin is most accurately modeled by clusters along the spindle axis. In contrast, cohesin is evenly distributed (barrel of 500-nm width × 550-nm length). Models of cohesin gradients that decay from the centromere or sister cohesin axis, as previously suggested, do not match experimental images. The fine structures of cohesin and condensin deduced with subpixel localization accuracy reveal critical features of how these complexes mold pericentric chromatin into a functional spring. 相似文献
108.
Biobanks are increasingly being established to act as mediators between patient-donors and researchers. In practice, some of these will close. This paper details the experiences of one such bank. We report interviews with the bank's staff and oversight group during the period when the bank ceased biobanking activity, reconfigured as a disseminator of best practice, before then closing altogether. The paper makes three distinct contributions: (i) to provide a detailed account of the establishment, operational challenges, and eventual closure of the bank, which makes clear the rapid turnover in a cycle of promise and disappointment; (ii) to explore this in terms of a novel analytical focus upon field, institutional, and individual expectations; and (iii) to use this typology to demonstrate how, even after the bank's closure, aspects of its work were reconfigured and reused in new contexts. This provides a unique empirical analysis of the under-reported issue of biobank closure. 相似文献
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Cécilia G. Maubaret Klelia D. Salpea Casey E. Romanoski Lasse Folkersen Jackie A. Cooper Coralea Stephanou Ka Wah Li Jutta Palmen Anders Hamsten Andrew Neil Jeffrey W. Stephens Aldons J. Lusis Per Eriksson Philippa J. Talmud Steve E. Humphries the Simon Broome Research Group the EARSII consortium 《PloS one》2013,8(12)