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991.
Reported are the results of a multiyear study in which reading comprehension and writing were integrated within an in-depth science instructional model (Science IDEAS) in daily 1.5 to 2 h daily lessons on a schoolwide basis in grades 3–4–5. Multilevel (HLM7) achievement findings showed the experimental intervention resulted in significant and consistent direct effects in grades 3–4–5 and complementary transfer effects in grades 6–7 on both ITBS Science (+1.08 Grade Equivalent Units [GE]) and ITBS Reading (+.57 GE). Discussed are implications of the findings and related research for changing grade K-5 curriculum policy to allocate increased instructional time for integrated science instruction.  相似文献   
992.
This article examines college student disengagement from sports, presents a multidimensional concept of athletic identity, and introduces a new measure intended to assist college counselors in their work with disengaged athletes. The Multidimensional Athletic Identity and Engagement Scale (MAIES) is introduced (Cronbach alpha .98, with subscale alphas between .78 and .96), and the results of exploratory and confirmatory factor analyses and convergent and divergent validity with 250 college student participants are presented. Using case examples, the authors discuss how counselors may use the MAIES in their work with students. Limitations of the study and suggestions for future research are discussed.  相似文献   
993.
Although there is a large body of research on the effectiveness of supplemental instruction for college undergraduates, very little of it has focused on transfer students, who often confront additional sources of stress and historically perform more poorly than their native student counterparts. In this study, we investigated the effectiveness of a peer-based supplemental instructional program in general and organic chemistry at a large state university over a six-year period, while considering differences across transfer and nontransfer students. The results suggest that the supplemental instruction improved outcomes overall but that nontransfer students benefit to a greater degree than transfer students, in the form of higher grades and pass rates, from attending supplemental instruction. The results suggest that peer-based supplemental instruction is a useful method to improve undergraduate student performance in chemistry, but more research is needed on ways to enhance the effectiveness of interventions in improving the performance of transfer undergraduate students in STEM fields.  相似文献   
994.
Bridging schools and communities has been a goal, if not hurdle, for reformers who aim to improve the education of low-income and underrepresented students from the bottom-up. Strategies to create these connections are often characterized as ‘brokerage’, where individuals or organizations bridge two or more social worlds. This paper details the design and implementation of educational technologies that support the brokering of school–community connections using a ‘culturally responsive computing’ (CRC) framework. Culturally responsive education is often limited to content and learning styles, which misses the opportunities it creates for a brokerage process that also connects to education-based social movements for economic access in underrepresented communities. This paper provides empirical support for the claim that the CRC framework is well suited for both purposes. It allows schools and communities to build assets together, translating the knowledge and skills of underrepresented communities into math and computing education, while illuminating the ways in which technologies can motivate education-based social movement building.  相似文献   
995.
996.
住宅输电线是世界上分布最广泛的网络,无处不在的家庭电源插座即将成为人们进入互联网世界的大门,期盼通过电线,将PC、电话、音响甚至电冰箱都能连成一气,统统连上网络,彼此沟通,而无需大费周折另外布线!要完全不出错,通过电源线进行讯号处理的复杂程度远远超过之前采用的任何技术.  相似文献   
997.
998.
Allergenic/antigenic proteins are known to induce Type I and Type III hypersensitivity reactions leading to allergic bronchopulmonary aspergillosis (ABPA) in immunocompetent host. The common structural features or intrinsic properties of the allergens/antigens leading to allergenicity in a host are not well understood. In the current report, comparative analysis of proteins on two dimensional gel electrophoresis (2D-3) and specific IgE immunoblots ofA. fumigatus secretory proteins (1st, 2nd and 3rd week culture filtrate proteins) was carried out. We observed a total of 159 proteins in 1st, 2nd and 3rd week culture filtrates ofA. fumigatus. Specific IgE immunoreactivity was observed in 75 proteins with different intensity. Third week culture filtrate showed maximum number of proteins, 142, and specific IgE immunoreactive proteins, 65. MALDI-TOF analysis resulted in putative identification of two allergens as hypothetical protein YBL057c fromSaccharomyces cereviseae and unnamed protein product fromDebaryomyces hansenii (similar to IPF14568 ofCandida albicans). Identification of a repertoire of specific IgE immunoreactive proteins will facilitate the studies on structure-function relationship of these proteins relevant for diagnosis and pathogenesis.  相似文献   
999.
In this paper the patenting activity of the international pharmaceutical industry in London between 1900 and 1966 is analysed. Although patent data as a measure of industrial activity is not without defects it can be used both as an adjunct to and as a surrogate for more conventional yardsticks such as concentration ratios, sales statistics and so on. The results indicate that patenting activity can be used as both an absolute and relative indicator of an industry's pace of technological change. They help pinpoint the international distribution of pharmaceutical research and development. If analysed by product or process they can aid in the understanding of why an industry's competitive behaviour is or is not primarily one of price rivalry. Finally, they illustrate the continuing role of the individual inventor.  相似文献   
1000.
数千年来,人类一直对死亡异常恐惧,科学能够帮助我们摆脱这一宿命吗?  相似文献   
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