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211.
The study reported in this paper concerns the tensions and conflicts that teachers experience while they enact a new set of reform-oriented curricular materials into their classrooms. Our focus is οn the interactions developed in two groups of teachers in two schools for a period of a school year. We use Activity Theory to study emerging contradictions and we elaborate on the construct of dialectical opposition to understand the nature of these contradictions and their potential for teacher learning. We provide evidence that discussions about contradictions and their dialectical character in the two groups support teachers to engage differently in mathematics teaching and learning and carry potentials for shifts in the practices that evolve in their classrooms. Our study addresses empirically in the context of mathematics teaching the philosophical claim about the role of contradictions as a driving force for any dynamic system.  相似文献   
212.
An important issue in the design of secondary-level education is the balance between conveying general and occupation-specific (vocational) skills. On the one hand, vocationally oriented programmes, providing occupation-specific skills with immediate labour market relevance, have repeatedly been shown to secure safe pathways into employment. On the other hand, these programmes tend to put less emphasis on developing general knowledge, skills and competencies, including numeracy and literacy, which are foundational to lifelong learning. Hence, when the needs of the labour market change, employees who opted for a vocational track when they were at secondary school risk being less flexible in adapting to such changes later in their career. The authors of this article examine whether this results in a trade-off between short-term gains and long-term losses by considering differences in the labour market careers of vocationally and generally educated respondents in the 2012 Programme for the International Assessment of Adult Competencies (PIAAC). Their results suggest that early labour market benefits of vocational specialisation decrease over time; the authors relate this to its lower ability to equip secondary school students – future employees – with skills for lifelong learning.  相似文献   
213.
Business professors were surveyed to determine their attitudes towards two methods of collecting students' teaching evaluations of faculty--the traditional paper-and-pencil method conducted in class and the online method conducted via the Internet. Faculty preferred the traditional paper method, mainly because they believed it would produce a higher and more accurate response than the online method. Faculty characteristics were examined to determine whether they were related to attitudes towards the online method of collecting teaching evaluations. No characteristics were found to be significantly associated with attitudes towards the online method. Suggestions for future researchers are offered.  相似文献   
214.
The performance in vibration environment of switching apparatus containing mechanical contact is an important element when judging the apparatus’s reliability. A piecewise linear two-degrees-of-freedom mathematical model considering contact loss was built in this work, and the vibration performance of the model under random external Gaussian white noise excitation was investigated by using Monte Carlo simulation in Matlab/Simulink. Simulation showed that the spectral content and statistical characters of the contact force coincided strongly with reality. The random vibration character of the contact system was solved using time (numerical) domain simulation in this paper. Conclusions reached here are of great importance for reliability design of switching apparatus.  相似文献   
215.
Homoharringtonine (HHT) has currently been used successfully in the treatment of acute and chronic myeloid leukemias and has been shown to induce apoptosis of different types of leukemic cells in vitro. Emerging evidence suggests that angiogenesis may play an important role in hematological malignancies, such as leukemia. How ever, whether HHT can relieve leukemia by anti-angiogenesis is still unknown. We investigated the anti-angiogenesis potential of HHT with the human umbilical vein endothelial cell line (ECV304) and leukemic cell line (K562) in vitro. Cellular proliferation was determined by MTT assay and apoptosis was analyzed by flow cytometry. The mRNA expression of vascular endothelial growth factor (VEGF) was assessed by RT-PCR and VEGF protein production was detected by Western blot. Inhibition of cell proliferation and induction of apoptosis by HHT were discovered in ECV304 cells, and appeared in a dose- and time-dependent manner. Also, treatment with HHT caused down-regulation of VEGF mRNA expression in K562 cells in similar dose- and time-dependent manner and inhibition of VEGF protein production in K562 cells in response to the enhancing concentration of HHT. The results demonstrated that HHT could also induce apoptosis in endothelium and down-regulate VEGF expression in K562 cells. In conclusion, we believe HHT has anti-angiogenesis potential and speculate that HHT might exert its anti-leukemia effects via reduction of angiogenesis.  相似文献   
216.
The education of child‐centered early childhood practitioners involves issues of content, pedagogy, relationships and context. Recent insights on the nature of child‐centered teaching generated by collaborative research with teachers, has highlighted its complexity and suggests that new ways of thinking about teacher education are needed. But developing a more learner‐centered approach to early childhood teacher education will be difficult, given the instrumentalist orientation in many institutions and in societies at large. This paper discusses the broad issues surrounding the development of a more learner‐centered approach to early childhood teacher education and describes several initiatives the authors have been involved in, in Australia and the United States.  相似文献   
217.
218.
Most counselors recognize the importance ofcultural competence in their work. As part ofeffective treatment, skills in accuratelydiagnosing clients from diverse backgrounds areessential, yet specific techniques addressingcultural differences to aid in the diagnosisprocess are underrepresented in the counselingliterature. The purpose of this article is tooffer one step toward the development ofdiagnostic methods suitable for an increasinglydiverse client base. The importance ofcultural competency during the diagnostic phaseof counseling is discussed, the nature ofculture and its influence on diagnosis isreviewed, and a practical conceptual frameworkthat can assist counselors in makingsystematic, culturally sensitive diagnosis ispresented.  相似文献   
219.
This study tested preschoolers' ability to provide accurate verbal associations to alcoholic beverage odors and whether this ability was related to parental drinking patterns and motivations. Older preschoolers performed better than younger preschoolers; photographic cues improved performance; children who correctly identified a substance by smell had socially appropriate knowledge of the culturally appropriate users of the substance; children reported liking substances that are used mainly by children and adults, and generally reported disliking substances whose use is legally limited to adults only; children were better at identifying substances they commonly use, but success at recognition of alcoholic beverages was related to heavier parental drinking and use of alcohol for escape reasons. Findings have implications for theories of socialization to drug use and for models of prevention.  相似文献   
220.
Whole system improvement—where the vast majority of schools improve—is difficult to achieve. Some jurisdictions use what turns out to be ‘wrong’ policy drivers like testing and evaluation. Rather, success turns out to depend on changing the culture of schools and their relationship to the infrastructure of policies and regulation. I examined the six cases studies in the light of whole system change criteria. Two of the case studies, South Africa and India, represent limited but useful examples in that they focus on basic skills like literacy. A second set of two studies, Escuela Nueva and LCP in Mexico, represent strong examples of how bottom up strategies can spread to significant levels. The final two, Long Beach in the US and Ontario, are strong examples of how deep change can be accomplished by focusing on a few core priorities and then building a culture over a number of years to support and sustain the changes. The paper then draws conclusions about the conditions that will be required for large scale change to occur.  相似文献   
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