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21.
Athanasios Paschalis Simone Fatichi Jakob Zscheischler Philippe Ciais Michael Bahn Lena Boysen Jinfeng Chang Martin De Kauwe Marc Estiarte Daniel Goll Paul J. Hanson Anna B. Harper Enqing Hou Jaime Kigel Alan K. Knapp Klaus S. Larsen Wei Li Sebastian Lienert Yiqi Luo Patrick Meir Julia E. M. S. Nabel Rom Ogaya Anthony J. Parolari Changhui Peng Josep Peuelas Julia Pongratz Serge Rambal Inger K. Schmidt Hao Shi Marcelo Sternberg Hanqin Tian Elisabeth Tschumi Anna Ukkola Sara Vicca Nicolas Viovy Ying‐Ping Wang Zhuonan Wang Karina Williams Donghai Wu Qiuan Zhu 《Global Change Biology》2020,26(6):3336-3355
Changes in rainfall amounts and patterns have been observed and are expected to continue in the near future with potentially significant ecological and societal consequences. Modelling vegetation responses to changes in rainfall is thus crucial to project water and carbon cycles in the future. In this study, we present the results of a new model‐data intercomparison project, where we tested the ability of 10 terrestrial biosphere models to reproduce the observed sensitivity of ecosystem productivity to rainfall changes at 10 sites across the globe, in nine of which, rainfall exclusion and/or irrigation experiments had been performed. The key results are as follows: (a) Inter‐model variation is generally large and model agreement varies with timescales. In severely water‐limited sites, models only agree on the interannual variability of evapotranspiration and to a smaller extent on gross primary productivity. In more mesic sites, model agreement for both water and carbon fluxes is typically higher on fine (daily–monthly) timescales and reduces on longer (seasonal–annual) scales. (b) Models on average overestimate the relationship between ecosystem productivity and mean rainfall amounts across sites (in space) and have a low capacity in reproducing the temporal (interannual) sensitivity of vegetation productivity to annual rainfall at a given site, even though observation uncertainty is comparable to inter‐model variability. (c) Most models reproduced the sign of the observed patterns in productivity changes in rainfall manipulation experiments but had a low capacity in reproducing the observed magnitude of productivity changes. Models better reproduced the observed productivity responses due to rainfall exclusion than addition. (d) All models attribute ecosystem productivity changes to the intensity of vegetation stress and peak leaf area, whereas the impact of the change in growing season length is negligible. The relative contribution of the peak leaf area and vegetation stress intensity was highly variable among models. 相似文献
22.
Chan Luo Fenghua LuXiaoli Wang Zhiqiang WangXiangping Li Fangqiang GongJianrong Jiang Qingyou LiuDeshun Shi 《Theriogenology》2013
It has been reported that buffalo (Bubalus bubalis) embryos reconstructed by somatic cell nucleus transfer (SCNT) can develop to the full term of gestation and result in newborn calves. However, the developmental competence of reconstructed embryos is still low. Recently, it has been reported that treating donor cells or embryos with trichostatin A (TSA) can increase the cloning efficiency in some species. Thus, the present study was undertaken to improve the development of buffalo SCNT embryos by treatment of donor cells (buffalo fetal fibroblasts) with TSA and explore the relation between histone acetylation status of donor cells and developmental competence of SCNT embryos. Treatment of donor cells with either 0.15 or 0.3 μM TSA for 48 hours resulted in a significant increase in the cleavage rate and blastocyst yield of SCNT embryos (P < 0.05). Meanwhile, the expression level of HDAC1 in donor cells was also decreased (0.4–0.6 fold, P < 0.05) by TSA treatment, although the expression level of HAT1 was not affected. Further measurement of the epigenetic maker AcH4K8 in buffalo IVF and SCNT embryos at the eight-cell stage revealed that the spatial distribution of acH4K8 staining in SCNT embryos was different from the IVF embryos. Treatment of donor cells with TSA resulted in an increase in the AcH4K8 level of SCNT embryos and similar to fertilized counterparts. These results suggest that treatment of donor cells with TSA can facilitate their nucleus reprogramming by affecting the acetylated status of H4K8 and improving the in vitro development of buffalo SCNT embryos. The AcH4K8 status at the eight-cell stage can be used as an epigenetic marker for predicting the SCNT efficiency in buffalos. 相似文献
23.
Yang CH Liu XM Si JJ Shi HS Xue YX Liu JF Luo YX Chen C Li P Yang JL Wu P Lu L 《PloS one》2012,7(6):e39696
The inhibitor κB protein kinase/nuclear factor κB (IKK/NF-κB) signaling pathway is critical for synaptic plasticity. However, the role of IKK/NF-κB in drug withdrawal-associated conditioned place aversion (CPA) memory is unknown. Here, we showed that inhibition of IKK/NF-κB by sulphasalazine (SSZ; 10 mM, i.c.v.) selectively blocked the extinction but not acquisition or expression of morphine-induced CPA in rats. The blockade of CPA extinction induced by SSZ was abolished by sodium butyrate, an inhibitor of histone deacetylase. Thus, the IKK/NF-κB signaling pathway might play a critical role in the extinction of morphine-induced CPA in rats and might be a potential pharmacotherapy target for opiate addiction. 相似文献
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Xiaokang Sun Jie Lv Fei Wang Chenyang Zhang Liangxiang Zhu Guangye Zhang Tongle Xu Zhenghui Luo Haoran Lin Xiaoping Ouyang Chunming Yang Chuluo Yang Gang Li Hanlin Hu 《Liver Transplantation》2024,14(3):2302731
Achieving high-performance in all-small-molecule organic solar cells (ASM-OSCs) significantly relies on precise nanoscale phase separation through domain size manipulation in the active layer. Nonetheless, for ASM-OSC systems, forging a clear connection between the tuning of domain size and the intricacies of phase separation proves to be a formidable challenge. This study investigates the intricate interplay between domain size adjustment and the creation of optimal phase separation morphology, crucial for ASM-OSCs’ performance. It is demonstrated that exceptional phase separation in ASM-OSCs’ active layer is achieved by meticulously controlling the continuity and uniformity of domains via re-packing process. A series of halogen-substituted solvents (Fluorobenzene, Chlorobenzene, Bromobenzene, and Iodobenzene) is adopted to tune the re-packing kinetics, the ASM-OSCs treated with CB exhibited an impressive 16.2% power conversion efficiency (PCE). The PCE enhancement can be attributed to the gradual crystallization process, promoting a smoothly interconnected and uniformly distributed domain size. This, in turn, leads to a favorable phase separation morphology, enhanced charge transfer, extended carrier lifetime, and consequently, reduced recombination of free charges. The findings emphasize the pivotal role of re-packing kinetics in achieving optimal phase separation in ASM-OSCs, offering valuable insights for designing high-performance ASM-OSCs fabrication strategies. 相似文献
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Divalent cations such as Ca+2 can act as bridges between lipopolysaccharide subunits causing large vesicles to form. During a two-stage ultrafiltration Ca+2 re-aggregated lipopolysaccharide subunits in protein solutions into large vesicles that could not pass a 300,000 nominal molecular weight cut-off ultrafiltration membrane. Such re-aggregation occurred at concentration ratio of hemoglobin Ao / lipopolysaccharide equal to or less than 17.0, or at concentration ratio of Ca+2 / hemoglobin Ao / lipopolysaccharide equal to or greater than 8.5. 相似文献
30.
Jia Liu Feng-Yu Liu Zhi-Qian Tong Zhi-Hua Li Wen Chen Wen-Hong Luo Hui Li Hong-Jun Luo Yan Tang Jun-Min Tang Jie Cai Fei-Fei Liao You Wan 《PloS one》2013,8(3)