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81.
Zhenhong Hu Han Y. H. Chen Chao Yue Xiao Ying Gong Junjiong Shao Guiyao Zhou Jiawei Wang Minhuang Wang Jianyang Xia Yongtao Li Xuhui Zhou Sean T. Michaletz 《Global Change Biology》2020,26(6):3429-3442
CO2 fluxes from wood decomposition represent an important source of carbon from forest ecosystems to the atmosphere, which are determined by both wood traits and climate influencing the metabolic rates of decomposers. Previous studies have quantified the effects of moisture and temperature on wood decomposition, but these effects were not separated from the potential influence of wood traits. Indeed, it is not well understood how traits and climate interact to influence wood CO2 fluxes. Here, we examined the responses of CO2 fluxes from dead wood with different traits (angiosperm and gymnosperm) to 0%, 35%, and 70% rainfall reduction across seasonal temperature gradients. Our results showed that drought significantly decreased wood CO2 fluxes, but its effects varied with both taxonomical group and drought intensity. Drought‐induced reduction in wood CO2 fluxes was larger in angiosperms than gymnosperms for the 35% rainfall reduction treatment, but there was no significant difference between these groups for the 70% reduction treatment. This is because wood nitrogen density and carbon quality were significantly higher in angiosperms than gymnosperms, yielding a higher moisture sensitivity of wood decomposition. These findings were demonstrated by a significant positive interaction effect between wood nitrogen and moisture on CO2 fluxes in a structural equation model. Additionally, we ascertained that a constant temperature sensitivity of CO2 fluxes was independent of wood traits and consistent with previous estimates for extracellular enzyme kinetics. Our results highlight the key role of wood traits in regulating drought responses of wood carbon fluxes. Given that both climate and forest management might extensively modify taxonomic compositions in the future, it is critical for carbon cycle models to account for such interactions between wood traits and climate in driving dynamics of wood decomposition. 相似文献
82.
Sun Qingshen Liu Xinyang Zhang Yanyan Song Yong Ma Xiuyan Shi Yue Li Xiuliang 《Probiotics and antimicrobial proteins》2020,12(2):535-544
Probiotics and Antimicrobial Proteins - This paper aims to study the effects of compound microbe-based beads on changes in the intestinal microbiota and alleviation of high-fat (HF)... 相似文献
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The supercritical fluid chromatographic separation of underivatized amino acids was explored using immobilized chiral crown ether column CROWNPAK CR-I (+) and mass spectrometric detection. The type of modifier, acidic additives, and the role of water were investigated. Enantioseparation was achieved for all 18 amino acids investigated with short retention times (less than 3 minutes) and average resolution of greater than 5.0. Analysis of enantiomerically pure standards demonstrated the D enantiomer eluted first for all amino acids using a CROWNPAK CR-I (+) column. 相似文献
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Amino Acids - Kinase-targeted therapy has been widely used as a lifesaving strategy for cancer patients. However, many patients treated with targeted cancer drugs are clinically observed to rapidly... 相似文献
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Binglin Yue Haiyan Yang Jian Wang Wenxiu Ru Jiyao Wu Yongzheng Huang Xianyong Lan Chuzhao Lei Hong Chen 《Cell proliferation》2020,53(7)
Exosomes are membrane‐bound extracellular vesicles that are produced in the endosomal compartment of most mammalian cell types and then released. Exosomes are effective carriers for the intercellular material transfer of material that can influence a series of physiological and pathological processes in recipient cells. Among loaded cargoes, non‐coding RNAs (ncRNAs) vary for the exosome‐producing cell and its homeostatic state, and characterization of the biogenesis and secretion of exosomal ncRNAs and the functions of these ncRNAs in skeletal muscle myogenesis remain preliminary. In this review, we will describe what is currently known of exosome biogenesis, release and uptake of exosomal ncRNAs, as well as the varied functions of exosomal miRNAs in skeletal muscle myogenesis. 相似文献
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在水热条件下合成纳米δ-Bi2O3负载多孔沸石球填料(Bi-PZSF),研究其对水体中Cr(Ⅵ)的吸附性能(包括等温吸附、吸附动力学和吸附稳定性)以及溶解氧、pH等因素对吸附过程的影响及其吸附机理。结果表明:朗格缪尔模型和准二级动力学模型对实验结果具有良好的拟合度,在中性条件下,水体中的溶解氧含量对吸附速率影响较小,Bi-PZSF的最大吸附量为955.69 mg·kg^-1,比天然沸石的吸附量提升了近120倍;Bi-PZSF在NO3^-和SO4^2-的溶液中呈现出较强的选择吸收Cr(Ⅵ)能力,Cr(Ⅵ)去除率均在97%以上;同时,Bi-PZSF在吸附Cr(Ⅵ)后表现出高稳定性。Cr(Ⅵ)的去除主要是通过与附着在Bi-PZSF上的纳米δ-Bi2O3的表面羟基交换完成的。 相似文献