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In this paper we explore two teachers' views on the role(s) of parents, the local community and children's home lives in the learning of mathematics in primary school. We use Moll and Greenberg's concept of ‘funds of knowledge’ and apply it to the case studies of two teachers working in the UK context. Issues of teachers' professional experience, ethnicity, class and gender emerge as significant in examining similarities and differences in the teachers' beliefs, understandings and practices in the area of linking home and school. We end with a discussion of some implications for teacher education and professional development. 相似文献
153.
Previous research has shown that a region of the midbrain, the periaqueductal gray matter (PAG), is critical for vocalization. In this review, we describe the results of previous investigations in which we sought to find out how PAG neurons integrate the activity and precise timing of respiratory, laryngeal, and oral muscle activity for natural-sounding vocalization using the technique of excitatory amino acid microinjections in cats. In these studies, all surgical procedures were carried out under deep anaesthesia. In the precollicular decerebrate cat two general types of vocalization, classified as voiced and unvoiced, could be evoked by exciting neurons in the lateral part of the intermediate part of the PAG. The patterns of evoked electromyographic activity were strikingly similar to previously reported patterns of human muscle activity. Coordinated patterns of activity were evoked with just-threshold excitation leading to the conclusion that patterned muscle activity corresponding to the major categories of voiced and voiceless sound production are represented in the PAG. In a parallel series of human and animal experiments, we also determined that the speech and vocalization respiratory patterns are integrated and coordinated with afferent signals related to lung volume. These data have led to the proposal of a new hypothesis for the neural control of vocalization: that the PAG is a crucial brain site for mammalian voice production, not only in the production of emotional or involuntary sounds, but also as a generator of specific respiratory and laryngeal motor patterns essential for human speech and song 相似文献
154.
J. A. Blanc C. A. Stone C. A. D'Urso T. L. M. Langlands J. R. Crooks D. E. Foster 《Journal of Radioanalytical and Nuclear Chemistry》1997,219(2):251-255
We are developing electronic laboratories to help introduce students to nuclear science. An electronic laboratory is a collection of computer simulations of nuclear science experiments. Each program allows students to set experimental parameters, collect data, and analyze results. Experiments can easily be repeated because the computer can compress time. Electronic laboratories are useful for schools with existing nuclear science programs because they can prepare students for actual laboratory work. They are also useful for schools without specialized facilities, since they give students an empirical understanding of nuclear science but do not require specialized equipment. We present three electronic experiments. 相似文献
155.
Six bands in the 0-v″ progression and three bands in the 1-v″ progression of the A2Πi → X2Πr visible system of SO+ have been recorded photoelectrically and rotationally assigned. Molecular constants for v′ = 0 and 1 in the A state and for v″ = 4–9 in the X state have been obtained using direct fitting and merging techniques. 相似文献
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On a recent attempt to define the interpretation basis in the many worlds interpretation of quantum mechanics 总被引:1,自引:0,他引:1
David Deutsch's 1985 algorithm to determine the preferred product structure and basis in the many worlds interpretation is examined. His heuristic argument for the conditions appearing in the algorithm is found wanting. The question of the existence and uniqueness of a final solution to his algorithm is discussed. The algorithm is shown to be inadequate to account for certain types of measurement which are, at least in principle, possible. 相似文献
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A procedure has been developed for the determination of the amount of gold clad on a brass base. The method does not require dissolution of the sample and utilizes the presence of copper in the base metal as an internal standard. 相似文献