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971.
Consensus decision making in human crowds 总被引:1,自引:0,他引:1
972.
Nakamura Y Ogura M Tanaka D Inagaki N 《Biochemical and biophysical research communications》2008,366(1):174-179
Yeast silent information regulator 2 (SIR2) is involved in extension of yeast longevity by calorie restriction, and SIRT3, SIRT4, and SIRT5 are mammalian homologs of SIR2 localized in mitochondria. We have investigated the localization of these three SIRT proteins of mouse. SIRT3, SIRT4, and SIRT5 proteins were localized in different compartments of the mitochondria. When SIRT3 and SIRT5 were co-expressed in the cell, localization of SIRT3 protein changed from mitochondria to nucleus. These results suggest that the SIRT3, SIRT4, and SIRT5 proteins exert distinct functions in mitochondria. In addition, the SIRT3 protein might function in nucleus. 相似文献
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黄土高原地区植被与气候的关系 总被引:46,自引:6,他引:40
利用地理信息系统技术结合典范对应分析和数量区划的方法。研究了黄土高原地区植被与气候之间的关系。排序结果表明:CCA的第一轴代表黄土高原植被和气候梯度的纬向变化,水分梯度是决定植被分布的最主要气候因子,热量梯度中的全年月平均最低气温、月平均最高气温、年均温也对植被的纬向性分布有较大的影响,黄土高原植被与气候梯度表现出明显的纬向性;CCA的第二轴代表黄土高原植被和气候梯度的经向性变化,热量梯度是决定植被经向性分布的最主要气候因子,水分梯度中的全年最大蒸散量对植被的经向性分布有较大的影响。黄土高原植被与气候梯度表现出明显的经向分布规律性。 相似文献
976.
Paulien Hogeweg Nobuto Takeuchi 《Origins of life and evolution of the biosphere》2003,33(4-5):375-403
In this paper we explore the impact of new levels ofselection in models of early evolution.We contrast two types of higher levels of selection. On the one hand we look at spatially explicitmodels of replicators in which, by a process of self-organization, new levels of selection ariseas large scale spatial patterns with a dynamics of their own. Alternatively externally imposedlevels of selection above the basic replicators are created by enclosing the replicators in vesicles.In this paper we first review some results on the impact of emerging higher levels of selection onthe evolutionary persistence of interacting co-evolvingreplicator systems. Moreover, we presenta vesicle model, which can potentially integrate emerging and imposed levels of selection. We use the models to examinethe classical problem information integration in early evolution.Supplementary material to this paper is available in electronic form at http://dx.doi.org/10.1023/A:1025754907141 相似文献
977.
Melanie J. B. Zeppel Brad R. Murray Derek Eamus 《Ecological Management & Restoration》2003,4(S1):S53-S59
Summary We used digital map overlays in a geographical information system (GIS) to quantify the potential impact of dryland salinity on the threatened flora and fauna of New South Wales (NSW). Geographical areas of conservation priority were identified based on richness of threatened species with distribution records overlapping dryland salinity. Two alternative schemes – Interim Biogeographical Regionalization for Australia (regions) and catchment boundaries (catchments) – were used to subdivide NSW. Sydney Basin, North Coast and South-western Slopes regions – and Hunter, Sydney, Macquarie, Murrumbidgee and Lachlan catchments – were identified as priority areas with more than 10 salinity-overlap species present. Five threatened plant species were identified as priority species due to more than half of their known distributions overlapping areas of dryland salinity. Threatened animal species of most concern had 10–50% of their records overlapping areas of dryland salinity. Our findings demonstrate that landscape exposure to dryland salinity should be used in conjunction with total richness of threatened species for prioritizing conservation of geographical areas with respect to the potential impact of dryland salinity on threatened species. 相似文献
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森林对水文过程影响研究进展 总被引:44,自引:5,他引:39
根据森林对水文过程的影响,森林水文学研究可以分为3个相互关联的方面:森林植被变化影响水量和水质定位试验研究;森林植被变化对水文循环机制的影响;旨在为资源管理和工程建设提供决策依据的基于物理过程分布式参数森林水文模型开发,定位试验研究不仅可以为森林水文模型参数化提供第一手资料,同时也可以揭示森林植被影响径流形成机制和进行径流成份的分割,径流形成机机制的研究则有助于改善基于物理过程模型的开发,模型研究反过来又可以为改进试验研究和径流形成机制研究提供指导。本文对以上3个方面的国内外研究进展进行了较为系统的概括。 相似文献
980.