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961.
Pengxue Li Qiaozhi Yu Xu Gu Chunmiao Xu Shilian Qi Hong Wang Fenglin Zhong Tobias I. Baskin Abidur Rahman Shuang Wu 《Current biology : CB》2018,28(17):2777-2786.e2
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Hugh A. L. Henry Mehdi Abedi Concepción L. Alados Karen H. Beard Lauchlan H. Fraser Anke Jentsch Juergen Kreyling Andrew Kulmatiski Eric G. Lamb Wei Sun Mathew R. Vankoughnett Susanna Venn Christiane Werner Ilka Beil Irmgard Blindow Sven Dahlke Maren Dubbert Alexandra Effinger Heath W. Garris Maite Gartzia Tobias Gebauer Mohammed A. S. Arfin Khan Andrey V. Malyshev John Morgan Charles Nock Janelle P. Paulson Yolanda Pueyo Holly J. Stover Xuechen Yang 《Ecosystems》2018,21(7):1432-1444
Reduced precipitation treatments often are used in field experiments to explore the effects of drought on plant productivity and species composition. However, in seasonally snow-covered regions reduced precipitation also reduces snow cover, which can increase soil frost depth, decrease minimum soil temperatures and increase soil freeze–thaw cycles. Therefore, in addition to the effects of reduced precipitation on plants via drought, freezing damage to overwintering plant tissues at or below the soil surface could further affect plant productivity and relative species abundances during the growing season. We examined the effects of both reduced rainfall (via rain-out shelters) and reduced snow cover (via snow removal) at 13 sites globally (primarily grasslands) within the framework of the International Drought Experiment, a coordinated distributed experiment. Plant cover was estimated at the species level, and aboveground biomass was quantified at the functional group level. Among sites, we observed a negative correlation between the snow removal effect on minimum soil temperature and plant biomass production the next growing season. Three sites exhibited significant rain-out shelter effects on plant productivity, but there was no correlation among sites between the rain-out shelter effect on minimum soil moisture and plant biomass. There was no interaction between snow removal and rain-out shelters for plant biomass, although these two factors only exhibited significant effects simultaneously for a single site. Overall, our results reveal that reduced snowfall, when it decreases minimum soil temperatures, can be an important component of the total effect of reduced precipitation on plant productivity. 相似文献
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Immunological and functional characterization of Mycobacterium leprae protein antigens: an overview 总被引:2,自引:0,他引:2
Jelle E.R. Thole Brigitte Wieles Josephine E. Clark-Curtiss Tom H.M. Ottenhoff Tobias F. Rinke de Wit 《Molecular microbiology》1995,18(5):791-800
A major focus of leprosy research in the last 10 years has been the identification and characterization of antigens of Mycobacterium leprae that interact with antibodies and T cells of the host's immune response. Through the combined efforts of many different laboratories, a substantial number of protein antigens have been identified and characterized. In this MicroReview we present an updated list of M. leprae protein antigens, and, with emphasis on recent developments, summarize what is known regarding their functional and immunological features. 相似文献
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The effect of the crystal lattice on the side-chain conformation andside-chain dynamics in peptides is investigated by solid-state NMR, using thecyclic decapeptide antamanide as an example. The study takes advantage of the13C assignment of the backbone and side chains based on theresolution-enhanced 2D spin-diffusion spectra by heteronuclear and homonucleardecoupling. The spectra even allow for a stereospecific assignment of the-carbons of the valine residue. It is found that the valine side chaincoexists in two static rotamer conformations which have not been observed byX-ray crystallography. In addition, remarkable effects of the crystal packingon the methyl-group rotation frequency are found from 13Crelaxation measurements. 相似文献
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