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991.
992.
Poly A RNA status and itsin vitro translation in a rabbit reticulolysate cell free system, were assessed in the skeletal muscle of young boys with Duchenne muscular dystrophy. Compared to normals there is a significant 48% increase in poly A RNA content of dystrophic muscle and its translatability was increased by 56% based on35S methionine incorporation into total protein systhesised. Immunoprecipitation of the translated products with monospecific antibodies showed that there is a 2.6 fold and a 2 fold increase in m and μ calpains respectively. This underlines the importance of both synthetic and degenerative activities in the early pathology in DMD muscle.  相似文献   
993.
In previous work it was established that the U.K. tractor industry was characterised by a high degree of technical change and that this was brought about by a process of more or less continuous incremental innovation. What was lacking was an analysis of how much technical change had been introduced and an indication of the role played by technical change in determining the performance of the U.K. tractor industry internationally. This paper concludes that on the average technical change in the industry had increased by as much as 150 percent during the years 1959–1977, though there is some indication that the rate of change might now be slowing somewhat.In order to determine the relative importance of technical change a method was developed to operationalise the distinction between price and non-price competition as well as the idea of intrinsic (technical) and associative (non-technical) factors as constituents of the latter. Based on cross-sectional data for the year 1978, it has been possible to show that British manufacturers tend to produce moderately priced tractors of low to medium technical sophistication: that German manufacturers produced the most technically sophisticated tractors; that the Italian manufacturers are not generally more sophisticated, technically, than the British producers except with respect to their development of four-wheel drive; and that COMECON-based producers combine a very low price with some degree of technical sophistication. Finally, it has been possible to show that the tractors with the highest sales are among the less sophisticated in each of the power ranges investigated and that new entrants used technical sophistication as an element of their entry strategy. The answer to the question of what allows the market leader to be market leader required the development of measures for associative non-price factors, such as the availability of a dealer network brand loyalty, resale prices of tractor models, etc. By performing a regression analysis on these measures along with previously derived measures of quality-adjusted price and relative technical sophistication it has been possible to show that market leadership is achieved as a result of a balance of a number of factors, the most important of which are the size of the dealer network, warrants cost, advertising, technical sophistication and price.  相似文献   
994.
In this paper, we consider the difficulties that a group of internationally educated female teachers (female IETs) encountered in the process of seeking certification in the Canadian Maritimes. We read their experiences in the context of neoliberalism, in particular how they are positioned in the labour force and also the teaching profession. We consider the material effects of differences such as gender, race, ethnicity, and regional location for the female IETs. Further, we underscore implications for teacher education.  相似文献   
995.
996.
There are two indisputable findings in science education research. First, students go to school with some intuitive beliefs about the natural world and physical phenomena that pose an obstacle to the learning of formal science. Second, these beliefs result from the confluence of two factors, namely, their everyday experience as they interact with the world around them and a set of operational constraints or principles that channel both perceptually and conceptually the way these experiences are perceived and interpreted. History of science suggests that the theories of early scientists through which they sought to explain physical phenomena relied mostly on ideas that closely fitted their experiences of the relevant phenomena. This characteristic of the early scientific ideas is the root of the epistemological difficulties that early scientists faced in their attempts to explain the phenomena. In this paper, we focus on the early theories in optics (from ancient Greek to the late Islamic scientific traditions) and argue that students face some of the same epistemological problems as early scientists in explaining vision and optical phenomena for the reason that students’ intuitive beliefs are also closely tied to particular phenomena and as a result the underlying notions are fragmentary and lack the necessary generality that would allow them to cover many disparate phenomena. Knowledge of these epistemological problems can help the instructor to identify the key elements for a better understanding of the formal theory of optics and, in turn, lead to a more effective instruction.  相似文献   
997.
Several scholars contend that learning with computer games and simulations results in students thinking more like professionals. Bearing this goal in mind, we investigated how a group of pharmacy students learnt with an in‐house developed computer simulation, SimPharm. Adopting situated cognition as our theoretical lens, we conducted a case study involving 20 undergraduate students to tease out how they made meaning of a clinical case differently in two different contexts: a typical paper‐based workshop and one enabled by SimPharm. The data collected included audio recordings of classroom discourse, focus group interviews and class observations. The findings identified differences in four areas: framing of the problem; problem‐solving steps and tools used; sources and meaning of feedback; and conceptualisation of the patient. These four areas can serve as axes along which future evaluations of educational simulations can be carried out based on their affordances.  相似文献   
998.
999.
Based on theoretically driven models, the Chicago School Readiness Project (CSRP) targeted low-income children's school readiness through the mediating mechanism of self-regulation. The CSRP is a multicomponent, cluster-randomized efficacy trial implemented in 35 Head Start-funded classrooms (N = 602 children). The analyses confirm that the CSRP improved low-income children's self-regulation skills (as indexed by attention/impulse control and executive function) from fall to spring of the Head Start year. Analyses also suggest significant benefits of CSRP for children's preacademic skills, as measured by vocabulary, letter-naming, and math skills. Partial support was found for improvement in children's self-regulation as a hypothesized mediator for children's gains in academic readiness. Implications for programs and policies that support young children's behavioral health and academic success are discussed.  相似文献   
1000.
In this article, Walter Parker brings structure and agency to the foreground of the current tumult of public schooling in the United States. He focuses on three structures that are serving as rules and resources for creative agency. These are a discourse of derision about failing schools, a broad mobilization of multiculturalism, and an enduring nationalism. Drawing on Anthony Giddens's structuration theory, Parker examines how these discourses figure in redefining school reform, redefining school curricula, and requiring schools once again to serve nationalistic purposes.  相似文献   
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