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61.
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Charles D. Laughlin 《Human nature (Hawthorne, N.Y.)》1991,2(3):171-213
Ample evidence from various quarters indicates that the perceptual-cognitive competence of the pre- and perinatal human being
is significantly greater than was once thought. Some of the evidence of this emerging picture of early competence is reviewed,
and its importance both as evidence of the biogenetic structural concept of “neurognosis” and for a theory of enculturation
is discussed. The literature of pre- and perinatal psychology, especially that of developmental neuropsychology, psychobiology,
and social psychophysiology, is incorporated, and some of the implications of these data for a theory of enculturation are
suggested.
This paper was presented at the annual meeting of the American Anthropological Association, Washington, D.C., November 1989.
Charles D. Laughlin, Professor of Anthropology at Carleton University, Ottawa, Canada, has done ethnographic fieldwork among
the So of northeastern Uganda and among Tibetan lamas in Nepal and India. He completed postdoctoral studies in neurophysiology
at the Institute of Neurological Sciences, University of Pennsylvania. He is editor of both theNeuroanthropology Network Newsletter and thePre- and Peri-Natal Psychology Journal. 相似文献
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65.
Marc Ledig Adam Holownia Jean-Christophe Copin Georges Tholey Irina Anokhina 《Neurochemical research》1996,21(3):313-317
The aim of this work was to investigate the effect of supplementation of a maternal alcohol diet with a grape extract on glial
cell development. Glial cells were cultured during 4 weeks from cortical brain cells of the new born offspring in DMEM medium
supplemented with fetal calf serum. Enzymatic markers of nerve cell development were measured (enolase isoenzymes and glutamine
synthetase). Since alcohol consumption produces free radicals the antioxidant system superoxide dismutase was also investigated.
Compared to the decrease found in only alcohol treated animals, all parameters except neuron-specific enolase were antagonized
and even stimulated after grape extract supplementation. The effect was more important after only 1 month than 3 months of
treatment. Also in the total brain an alcohol antagonizing effect and a glutamine synthetase activation were found. Our data
demonstrate that addition of a grape extract to the maternal alcohol diet may partially or completely overcome the alcohol
induced retardation of glial cell development. 相似文献
66.
多功能农业景观:内涵、进展与研究范式 总被引:2,自引:0,他引:2
多功能农业景观是景观尺度下农业多功能性的空间表征,具有生物多样性保护、田园风光留存和地域文化传承等多种重要的非经济功能。构建多功能农业景观是促进区域农业可持续发展与人类福祉提升的重要途径,同时也是多学科交叉的综合性研究。在已有景观生态学研究范式的基础上,探讨了多功能农业景观的内涵和国内外相关研究进展,并提出了"格局-功能-需求-管理"的多功能农业景观研究范式。与此同时,绘制了新研究范式的概念框架,通过划分四大研究模块具体分析了如何基于新研究范式开展多功能农业景观的构建、评价和管理等工作。本研究为实现区域农业景观的可持续发展和阐明多功能农业景观的内在运行机制奠定理论基础提供支持,为乡村生态景观营造关键问题的解决与多功能农业景观的实际构建提供帮助。 相似文献
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As a factor associated with urban management and planning, urban development intensity (UDI) could in fact form the basis for a new rationale in coordinating urban sustainable development and reducing CO2 emissions. However, existing literature engaging in the task of quantifying the impacts of urban development intensity on CO2 emissions is limited. Therefore, the goal of this study is to quantify the relationship between urban development intensity and CO2 emissions for a panel made up of the five major cities in China (Beijing, Shanghai, Tianjin, Chongqing and Guangzhou) using time series data from 1995 to 2011. Firstly, this study calculated CO2 emissions for the five selected cities and presented a comprehensive index system for the assessment of the level of urban development intensity based on six aspects (land-use intensity, economic intensity, population intensity, infrastructure intensity, public service intensity and eco-environmental intensity) using locally important socioeconomic variables. Panel data analysis was subsequently utilised in order to quantify the relationships between urban development intensity and CO2 emissions. The empirical results of the study indicate that factors such as land-use intensity, economic intensity, population intensity, infrastructure intensity and public service intensity exert a positive influence on CO2 emissions. Further, the estimated coefficients suggest that land-use intensity is the most important factor in relation to CO2 emissions. Conversely, eco-environmental intensity was identified as having a major inhibitory effect on CO2 emission levels. The findings of this study hold important implications for both academics and practitioners, indicating that, on the path towards developing low-carbon cities in China, the effects of urban development intensity must be taken into consideration. 相似文献
70.
H. S. Heide-Jørgensen 《Planta》1991,183(4):511-519
Transmission electron microscopy was used to investigate the development and ultrastructure of the cuticles of the bladder primordium and other parts of Utricularia, the stem of Cuscuta gronovii, and the leaves of Athanasia parviflora. In all materials investigated, except the apical meristem of Cassytha pubescens, the first-formed cuticle, named the procuticle, was very electron dense and apparently amorphous in texture. Later, the procuticle changed its ultrastructural appearance: in all species having a procuticle it lost much of its electron density. Simultaneously, it developed into a lamellar structure in U. lateriflora and Cuscuta, and became part of a lamellar cuticle proper. In U. sandersonii and Athanasia the procuticle generally remained without visible structure. The velum of the pavement epithelium of Utricularia is considered to be a slightly modified procuticle which has become loosened from the epithelial cells and stretched. 相似文献