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931.
A standardized procedure was developed for eliciting those details of a library's service policies that are important to its users and for recording the data by checking appropriate categories on a form. This inventory procedure covers the entire spectrum of user services and accommodates a wide range of policies. The inventory was originally designed for use by trained interviewers in largescale surveys of academic medical libraries. However, it is also suitable for other kinds of libraries, and the Interview Guide and Checklist can be used for a self-survey by library staff. In addition to survey use, the inventory has a variety of educational, administrative, managerial, and research applications. A method for weighting the categorical inventory data to reflect the relative desirability of different policies makes it possible to calculate scores indicating how a library's policies compare with those of an "optimal" library. An analogous inventory of the services a library provides to other libraries was developed for surveying major backup resources in the medical library system.  相似文献   
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Organic acid disorders are inherited metabolic disorders in which organic acids accumulate in tissues and biological fluids of affected individuals. Classical organic acidurias include methylmalonic aciduria, propionic aciduria, isovaleric aciduria and maple syrup urine disease (MSUD). They are considered the most frequent metabolic disorders among severely ill children. Patients frequently present with acute symptoms early in life. 420 cases clinically suspected to have organic aciduria, with upper age limit of 12 years for a 2-year period (January 2007–December 2008) were enrolled into this study. Metabolic acidosis and neurological symptoms were the most common signs. Screening tests and thin layer chromatography were done for detection of organic acidurias. Identification and quantitation of organic acids in urine and quantification of amino acids in blood were done by high performance liquid chromatography. Out of 420 patients, 45 patients (10.7%) were found to have organic acidurias. 15 cases of methylmalonic aciduria, 16 cases of propionic aciduria, 13 cases of MSUD, and one case of isovaleric aciduria were diagnosed. Results demonstrate the importance of testing for organic acidurias. Since organic aciduria may cause irreversible brain damage if not treated, we recommend selective screening amongst severely ill children despite implied extra costs.  相似文献   
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Biology of the twenty-first century is an increasingly quantitative science. Undergraduate biology education therefore needs to provide opportunities for students to develop fluency in the tools and language of quantitative disciplines. Quantitative literacy (QL) is important for future scientists as well as for citizens, who need to interpret numeric information and data-based claims regarding nearly every aspect of daily life. To address the need for QL in biology education, we incorporated quantitative concepts throughout a semester-long introductory biology course at a large research university. Early in the course, we assessed the quantitative skills that students bring to the introductory biology classroom and found that students had difficulties in performing simple calculations, representing data graphically, and articulating data-driven arguments. In response to students'' learning needs, we infused the course with quantitative concepts aligned with the existing course content and learning objectives. The effectiveness of this approach is demonstrated by significant improvement in the quality of students'' graphical representations of biological data. Infusing QL in introductory biology presents challenges. Our study, however, supports the conclusion that it is feasible in the context of an existing course, consistent with the goals of college biology education, and promotes students'' development of important quantitative skills.  相似文献   
938.
This study investigates how school demographics and their interactions with policies affect the mobility behaviors of public school teachers with various human capital characteristics. Using data from North Carolina from 1995 to 2006, it finds that teachers’ career stage and human capital investments dominate their decisions to leave public school teaching and school demographic characteristics play a dominant role in intra-system sorting. Schools serving at-risk children struggle to attract and retain teachers with desirable observable characteristics. We find evidence to suggest that across-the-board school-based pay-for-performance policies have small but significant associations with mobility decisions and appear to exacerbate inequities in the distribution of teacher qualifications.  相似文献   
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This special issue is dedicated to recentdevelopments within cognitive load theory (CLT)and identifies some instructional implicationsof the interaction between informationstructures and cognitive architecture. Thepresent article discusses the different studiesin this special issue. An important conclusionis that recent CLT research recognizes thelearners' level of expertise as an importantfactor mediating the relation between cognitivearchitecture, information structures, andlearning outcomes. In this context, we discussthe role of expertise in CLT research and therole of CLT in expertise research. Based onthis discussion, the use of CLT as a tool todevelop expertise is identified as a verypromising approach.  相似文献   
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