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941.
942.
Do 9‐month‐old infants motorically simulate actions they perceive others perform? Two experiments tested whether action observation, like overt reaching, is sufficient to elicit the Piagetian A‐not‐B error. Infants recovered a toy hidden at location A or observed an experimenter recover the toy. After the toy was hidden at location B, infants in both conditions perseverated in reaching to A, demonstrating that active search by the infant is not necessary for the A‐not‐B error. Consistent with prior research, infants displayed an ipsilateral bias when reaching, the so‐called mysterious midline barrier. A similar ipsilateral bias was also observed depending on the manner in which the experimenter reached; infants perseverated following observation of ipsi‐ but not contralateral reaches by the experimenter. Thus, infants perseverated only following observation of actions they themselves were able to perform, suggesting that they coded others' actions in terms of motor simulation.  相似文献   
943.
One of the continuing challenges posed by unprecedented urbanization in the developing countries is the provision of adequate housing. Over the last three decades, Nigeria, like several developing countries, has emphasised public housing schemes, but with little success. This coincides with global paradigm shift from direct public provision of housing to the enablement of private shelter initiatives and housing production. The paper discusses private housing development features and dynamics and the factors affecting the sector in the country. It argues for the creation of an enabling environment, including support of housing initiatives and investments by householders, small-scale providers, and entrepreneurial private firms. The paper identifies the implications of enabling strategy for housing finance, access to land, residential infrastructure, institutional regulations and building materials and related industry particularly in the light of the need for the private sector to play greater roles in housing. It draws from aspects of empirical study by the authors and some review of housing policy-related issues.  相似文献   
944.
945.
In designing appropriate devices for the development of a functional pancreatic substitute, computational models capable of accurately predicting cellular behavior constitute a critical aspect. This study investigated the model-based design, fabrication and in vitro and in vivo experimental characterization of a pancreatic substitute consisting of mouse insulinoma cells encapsulated in agarose in a disk-shaped construct. Two construct prototypes were examined: (i) a single disk construct comprised of agarose and βTC3 cells; and (ii) a buffered disk construct, consisting of agarose and βTC3 cells, coated with an additional layer of pure agarose. Diffusional studies of glucose and insulin were performed to characterize the transport properties of the material. Three dimensional oxygen diffusion-reaction models were used to predict the appropriate cell loadings for the two construct prototypes under varying external oxygen tensions. In vitro and in vivo experiments found the overall viable cell number for each construct prototype plateaued to the same value, regardless of the initial cell seeding number, when constructs were placed under identical environmental conditions. Furthermore, mathematical model calculations correlated well with experimental in vitro and in vivo results of cell viability, indicating oxygen tension to be the dominating factor in establishing total viable cell number in these constructs. These results indicate that the development of a computational model capable of accurately predicting overall cell viability is useful for the development of tissue engineered constructs, when permissive matrices and continuous cell lines are used. The applicability of this modeling and experimental methodology in the development of agarose-based constructs for use as a bioartificial pancreas is discussed. The authors would like to dedicate this paper to the memory of the colleague, friend, and mentor Professor Ioannis (Yanni) Constantinidis, who died suddenly and untimely on April 16, 2006.  相似文献   
946.
文章探讨的是作者书写"看见自我"的视觉经验及其反思。在唐代诗人中,题咏自己的肖像画、书写揽镜自照心情者,以白居易(772~846)的作品最多,至少有十五首。文章即以白居易观看自己的肖像画以及照镜题材的诗作为例,分析诗人从凝视自我的视觉体验中感知的自我意识。诗人透过画像再现或镜面反射,得知三重层次的"自我形象"——真实自我的幻影、他人眼中的"我"以及理想之"我"的期许。  相似文献   
947.
We consider linear combinations of “natural” timescales and choose the “best” one which provides the minimum coefficient of variation of the lifetime. Our time scale is in fact a generalized Miner time scale because the latter is based on an appropriate weighting of the times spent on low and high level loadings. The suggested modus operandi for finding the“best” time scale has many features in common with the approach suggested by Farewell and Cox (1979) and Oakes (1995) which is devoted to multiple time scales in survival analysis. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
948.
This paper is a revision of an address given upon receipt of the Leo G. Reeder Award for Distinguished Scholarship in Medical Sociology. It was presented on August 14, 1990 to The Medical Sociology Section of the American Sociological Association during its annual meetings, held in Washington, DC. Herein I reflect on the structured silence of personal bodily experience and on the unfinished paradigmatic challenge of feminism as a way of leading to a new praxis in medical sociology.  相似文献   
949.
950.
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