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71.
The first year of a 5 year professional development project for elementary teachers in two mid-western states integrated a bridge of two distinctly different distance education networks (T-1 and fiber optics) to provide science professional development for elementary school teachers in rural communities. Interactive television (ITV), the title given to the distance component, consisted of a series of twenty-four, 2 h presentations by scientists and content specialists. It provided expansion to the science pedagogical content knowledge of the elementary teachers involved. Eighty-five teachers in 38 school districts from the two states completed individual surveys following the final ITV session. Analysis of variance of participants post-session survey scores yielded differences (p < 0.05) on the subscales measuring perceived effectiveness of using distance education for professional development purposes and years of teaching experience. Teachers with over 20 years of classroom experience perceived the use of distance education technologies for science professional development to be more effective than teachers with 16–20 years of classroom experience. These results might suggest another digital divide.  相似文献   
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反应级数的确定在化学动力学研究中非常重要,现给出了利用计算机和用微分法确定反应级数的方法.为了使编程的程序简短、高效,采用MATLAB语言作为编程语言.  相似文献   
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Luciferase from firefly lantern extract was immobilized on CNBr-activated Sepharose 4B. The kinetic properties of immobilized luciferase were extensively studied. TheK m′ for D-luciferin is 11.9 μmol/L, the optimum pH and temperature for Sepharose-bound enzyme were 7.8 and 25°C respectively. A luminescence fiber optic biosensor, making use of immobilized crude luciferase, was developed for assay of ATP. The peak light intensity was linear with respect to ATP concentration in range of 10−9–10−5 mol/L. A biological application was also demonstrated with the determination of serum ATP from rats bred in low versus normal oxygen environments.  相似文献   
76.
We designed from scratch a minimal manual of the kind proposed by Carroll (1990) for Unix e-mail. The design process involved acquiring from a set of experts information about e-mail use that would be helpful to novices, and acquiring from novices information that guided subsequent versions of the manual. The seventh version of the minimal manual was tested against a commercial manual, in a comparative performance experiment, with 30 naive subjects. It had approximately 13% of the pages of the commercial manual; it resulted in 30% faster learning and more effective use of the e-mail system overall, and significantly better performance on individual subtasks; including the recovery from errors. Significantly more users were satisfied with it than with the conventional manual. Carroll's general principles of manual design for minimal manuals were found to be a good basis for design, and we suggest these guidelines are suitable for the design of such manuals from scratch.  相似文献   
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The relationship of past and present and the linking of characters through time and place are themes that underlie the work of many writers for children. This article considers the use of the Ghost as a literary device to allow the exploration of what is, what has been, and what might have been, particularly in the 1973 Carnegie Medal Winner,The Ghost of Thomas Kempe, by Penelope Lively.Judith Armstrong was brought up in Lancashire. She has travelled widely, and taught young children in England and Ethiopia. She is currently working on themes associated with the supernatural in children's books.  相似文献   
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This study investigated patterns of college attendance using data from a nationwide and contemporary sample of 2112 rural youth. We found that more than half of rural youth attended two-year institutions at some point during their college career and about a fourth initially enrolled in a two-year college before enrolling in a four-year college. Results also revealed that parental education, college preparatory track and preparation experiences, and teacher expectations predicted students’ college attendance patterns. Our findings point to the importance of two-year colleges and highlight the influence of family characteristics and students’ schooling experiences in the postsecondary trajectories of rural youth.  相似文献   
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In 2001, for the first time in the history of the International Association for Counselling, International Conference was held in a developing Asian country–India, with the theme Families in Transition–Counselling in Transition–Meeting the Challenges Ahead. This special issue contains some of the presentations made by Indian participants during this conference which best reflect the challenges and diversities of counseling efforts with families in India. The first article was specially written for this issue in order to give an international relationship of this journal an in depth contextual understanding of Indian families in transition and the challenges they pose to the contemporary Indian counselor. Two articles are reflected to counseling families affected by socio-politial and economic changes. Five authors have written on counseling related to physical and mental disability/addiction and last two articles are reflected to authors experiences as family counselors.  相似文献   
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