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Human biology seeks to understand human variation and the biological, environmental, social, and historical influences on that variation. Views of the nature of both variation and environment have changed during the past 100 years. Typological approaches to nature and human diversity shifted to an evolutionary perspective during the first half of the 20th century. In the second half, widespread human biological variation was documented and interpreted in terms of adaptation to the environment. Environmental physiology and reproductive ecology continue to document environmental influences on human biological functioning, but with (1) an expanded concept of environment that acknowledges more fully the interactions among its physical, biotic, and social aspects and (2) an expanded theoretical basis, drawing on evolutionary ecology and life history theory, acknowledging tradeoffs and changing constraints and opportunities over the lifetime. Human biology gains from greater interaction with other fields, such as political ecology, but also contributes to them. [Keywords: biological anthropology, human ecology, adaptation, environmental physiology, reproductive ecology]  相似文献   

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Nature and Society: Anthropological Perspectives. Philippe Descola and Gisli Pálsson. eds. New York: Routledge, 1996. 310pp.  相似文献   

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An official organization responsible for ecological research and nature conservation was formed in 1949. This paper traces its development and vicissitudes, first as an independent Nature Conservancy, then as a part of the Natural Environment Research Council, and finally as the Nature Conservancy Council. Much has been achieved: ecology is now a household word; there is a strong voluntary tide for nature conservation in the country; and there have been notable achievements in practical conservation. But the dangers to nature in Britain have proved to be much greater than anticipated.  相似文献   

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This year (2014) marks the 270th anniversary of Jean‐Baptiste de Lamarck's birth, which presents a good occasion to reflect on the wide‐reaching, although largely ignored, legacy of the French naturalist and its modern‐day renaissance. A discussion is provided of the broad and controversial influence of Lamarckian thought on science, politics and art, with a focus on Lamarck's curious recent comeback to the public and academic eyes in relation to the burgeoning discipline of epigenetics. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 114 , 242–247.  相似文献   

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Reversible hormone conjugations in plants may represent physiologically and biochemically essential pathways in the regulation of endogenous levels of biologically active pools of phytohormones. Conjugates of auxins, gibberellins, and cytokinins are now widely recognized as serving a storage function for rapid (im)mobilization of these phytohormones, depending on a variety of environmental, developmental, and physiological factors. The significance of conjugates of other phytohormones (abscisic acid, ethylene, jasmonic acid, and salicylic acid) is less well understood. Recent developments in studies on phytohormone conjugation, involving both biochemical and molecular biology approaches, are presented here. The nature and possible functions of the conjugates are discussed. Conjugates of other compounds (e.g., anthranilate-glucosides) are also known (for review, see Hösel, 1981). However, it is not known whether these compounds have a signaling function.  相似文献   

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Intratumor heterogeneity inherent in the majority of human cancers is a major obstacle for a highly efficient diagnosis and successful prognosis and treatment of these diseases. Being a result of clonal diversity within the same tumor, intratumor heterogeneity can be manifested in variability of genetic and epigenetic status, gene and protein expression, morphological structure, and other features of the tumor. It is most likely that the appearance of this diversity is a source for the adaptation of the tumor to changes in microenvironmental conditions and/or a tool for changing its malignant potential. In any case, both processes result in the appearance of cell clones with different undetermined sets of hallmarks. In this review, we describe the heterogeneity of molecular disorders in various human tumors and consider modern viewpoints of its development including genetic and non-genetic factors of heterogeneity origin and the role of cancer stem cells and clonal evolution. We also systematize data on the contribution of tumor diversity to progression of various tumors and the efficiency of their treatment. The main problems are indicated in the diagnosis and therapy of malignant tumors caused by intratumor heterogeneity and possible pathways for their solution. Moreover, we also suggest the key goals whose achievement promises to minimize the problem of intratumor heterogeneity and to identify new prognostic, predictive, and target markers for adequate and effective treatment of cancer.  相似文献   

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Computational inverse design and consequent experimental results allow for the identification of new tetrahedrite‐mineral compositions as promising absorber candidates in drift‐based thin‐film solar cells. In device simulations, cell efficiencies above 20% are modeled with absorber layers as thin as 250 nm. These new compositions thus open opportunities for realization of a new class of high‐efficiency thin‐film solar cell.  相似文献   

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Hydrogen production by water splitting may be an appealing solution for future energy needs. To evolve hydrogen efficiently in a sustainable manner, it is necessary first to synthesize what we may call a 'super catalyst' for water oxidation, which is the more challenging half reaction of water splitting. An efficient system for water oxidation exists in the water oxidizing complex in cyanobacteria, algae and plants; further, recently published data on the Manganese-calcium cluster have provided details on the mechanism and structure of the water oxidizing complex. Here, we have briefly reviewed the characteristics of the natural system from the standpoint of what we could learn from it to produce an efficient artificial system. In short, to design an efficient water oxidizing complex for artificial photosynthesis, we must learn and use wisely the knowledge about water oxidation and the water oxidizing complex in the natural system. This article is part of a Special Issue entitled: Photosynthesis Research for Sustainability: from Natural to Artificial.  相似文献   

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