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61.
This ethnographic study of a third grade classroom examined elementary school science learning as a sociocultural accomplishment. The research focused on how a teacher helped his students acquire psychological tools for learning to think and engage in scientific practices as locally defined. Analyses of classroom discourse examined both how the teacher used mediational strategies to frame disciplinary knowledge in science as well as how students internalized and appropriated ways of knowing in science. The study documented and analyzed how students came to appropriate scientific knowledge as their own in an ongoing manner tied to their identities as student scientists. Implications for sociocultural theory in science education research are discussed. John Reveles is an assistant professor in the Elementary Education Department at California State University, Northridge. He received his Ph.D. from the University of California, Santa Barbara in 2005. Before pursuing his Ph.D., he worked as a bilingual elementary school teacher for 3 years. His research focuses on the development of scientific literacy in elementary school settings; sociocultural influences on students' academic identity; equity of access issues in science education; qualitative and quantitative research methods. Within the Michael D. Eisner College of Education, he teaches elementary science curriculum methods courses, graduate science education seminars, and graduate research courses. Gregory Kelly is a professor of science education at Penn State University. He is a former Peace Corps Volunteer and physics teacher. He received his Ph.D. from Cornell in 1994. His research focuses on classroom discourse, epistemology, and science learning. This work has been supported by grants from Spencer Foundation, National Science Foundation, and the National Academy of Education. He teaches courses concerning the uses of history, philosophy, sociology of science in science teaching and teaching and learning science in secondary schools. He is editor of the journal Science Education. Richard Durán is a Professor in the Gevirtz Graduate School of Education, University of California, Santa Barbara. His research and publications have been in the areas of literacy and assessment of English Language Learners and Latino students. He has also conducted research on after school computer clubs, technology and learning as part of the international UC Links Network. With support from the Kellogg Foundation, he is implementing and investigating community and family-centered intervention programs serving the educational progress of Latino students in the middle and high school grades.  相似文献   
62.
Pedro Gutiérrez Bueno wrote two editions of a chemistry textbook between 1788 and 1802. The paper offers a comparative view of both editions taking into account Gutiérrez Bueno’s biography, his intended audience and the changes related to the so-called chemical revolution. Some conclusions are at odds with common images about scientific revolutions and the role of textbooks in science. The analysis aims to shed some light on the multiple historical forces shaping textbooks and the way in which scientific change is assimilated by their writers. This research was partially supported by the program BHA2002-04611-CO3-02  相似文献   
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This paper gives background information on early childhood services in Ireland and presents the results of a survey of the preschool experiences of 1065 children. The results of the survey suggest that the majority of children experienced some form of early childhood service before starting school. The most common service was a playgroup although a significant proportion of the children had experienced home‐based care with a relative or family day care provider. The implications of the findings for the development of a policy on early childhood services are discussed.  相似文献   
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During the last decades, the education system has been marked by distinct processes of internationalisation. In the field of higher education, there are numerous and varied schools with different international profiles. This paper focuses on processes of internationalisation in the German sector of higher education. We contrast two higher secondary schools with international profiles: one international school in a West German metropolitan region with a long tradition and a younger internationally-profiled school located in the periphery of an East German urban centre. This institutional analysis presents school cultural similarities and differences with regard to different claims and concepts of internationality. This analysis is complemented by a reconstruction of three patterns of biographical meaning examining the internationality of pupils and their respective habitual fit to these internationally-profiled schools. We draw on qualitative data, consisting mainly of interviews with head teachers and pupils of these two schools. We argue that these differing regional forms of internationalisation indicate a stratification and hierarchisation in the field of higher education in Germany.  相似文献   
67.
Despite its frequent use, there is little understanding of the concept of differential among upper high school and undergraduate students of physics. As a first step to identify the origin of this situation and to revert it, we have done a historic and epistemological study aimed at clarifying the role and the meaning of the differential in physics and at improving curricular and teaching models in the sense of Gilbert et al. (Gilbert J.K., Boulter C., & Rutherford, M.: 1998a, International Journal of Science Education 20(1), 83–97, Gilbert J.K., Boulter C., & Rutherford, M.: 1998b, International Journal of Science Education 20(2), 187–203). We describe the contributions of Leibniz and Cauchy and stress their shortcomings, which are overcome by the alternative definition proposed by the French mathematician Fréchet, dating from early 20th century. As a result of this study, we answer to some fundamental questions related to a proper understanding of the differential in physics education (for 17–19 years old students).  相似文献   
68.
The Inductive Query By Example (IQBE) paradigm allows a system to automatically derive queries for a specific Information Retrieval System (IRS). Classic IRSs based on this paradigm [Smith, M., & Smith, M. (1997). The use of genetic programming to build Boolean queries for text retrieval through relevance feedback. Journal of Information Science, 23(6), 423–431] generate a single solution (Boolean query) in each run, that with the best fitness value, which is usually based on a weighted combination of the basic performance criteria, precision and recall.  相似文献   
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Introduction

Extremely high glucose concentrations have been shown to interfere with creatinine assays especially with Jaffe method in peritoneal dialysate. Because diabetes is the fastest growing chronic disease in the world, laboratories study with varying glucose concentrations. We investigated whether different levels of glucose spiked in serum interfere with 21 routine chemistry and thyroid assays at glucose concentrations between 17-51 mmol/L.

Materials and methods

Baseline (group I) serum pool with glucose concentration of 5.55 (5.44-5.61) mmol/L was prepared from patient sera. Spiking with 20% dextrose solution, sample groups were obtained with glucose concentrations: 17.09, 34.52, and 50.95 mmol/L (group II, III, IV, respectively). Total of 21 biochemistry analytes and thyroid tests were studied on Abbott c8000 and i2000sr with commercial reagents. Bias from baseline value was checked statistically and clinically.

Results

Creatinine increased significantly by 8.74%, 31.66%, 55.31% at groups II, III, IV, respectively with P values of < 0.001. At the median glucose concentration of 50.95 mmol/L, calcium, albumin, chloride and FT4 biased significantly clinically (-0.85%, 1.63%, 0.65%, 7.4% with P values 0.138, 0.214, 0.004, < 0.001, respectively). Remaining assays were free of interference.

Conclusion

Among the numerous biochemical parameters studied, only a few parameters are affected by dramatically increased glucose concentration. The creatinine measurements obtained in human sera with the Jaffe alkaline method at high glucose concentrations should be interpreted with caution. Other tests that were affected with extremely high glucose concentrations were calcium, albumin, chloride and FT4, hence results should be taken into consideration in patients with poor diabetic control.Key words: assay interference, glucose interference, preanalytical phase, creatinine, Jaffe kinetic assay, thyroid function tests  相似文献   
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