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Who borrows laptop computers in an academic health sciences library? Why do they choose to check out laptops? In a survey, laptop computer users responded that the laptops were used most frequently to do class-related work. Laptops were most often checked out because they could be taken to a quiet area of the library or to where the user had more room to work. The majority of such borrowers were satisfied or very satisfied with the laptops and the service from the library. The majority of those completing the survey were medical school students and graduate students. The circulation of laptop computers at this academic health sciences library is a very successful and popular program.  相似文献   
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This study explored the relationship between metacognition and intelligence in a group of normal adolescents. The relationship has strong theoretical support in current conceptions of intelligence. For the purposes of this study metacognition was assessed across three different cognitive problem sets. Correlational analyses indicated a nonsignificant relationship between intelligence and metacognition. These results suggest that tests of metacognition and intelligence may tap unrelated aspects of cognition and that additional research will be required to understand the relationship between these two constructs.  相似文献   
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IntroductionTwo new formulas, the Martin-Hopkins and the Sampson formula, were recently developed to overcome shortcomings of the Friedewald formula for calculating LDL-cholesterol. We aimed to compare the concordance of the two formulas with apolipoprotein B (apoB), a surrogate marker of the number of LDL particles.Materials and methodsIn a study of serum lipid data of 1179 patients who consulted the AZ St-Jan Hospital Bruges for cardiovascular risk assessment, the correlation and concordance of the Friedewald, Martin-Hopkins and Sampson formulas with apoB concentration, measured by immunonephelometry, were determined and compared.ResultsThe Martin-Hopkins formula showed significantly higher correlation coefficient than the Friedewald formula with apoB in the entire dataset and in patients with low LDL-cholesterol < 1.8 mmol/L. Both Martin-Hopkins and Sampson formulas yielded > 70% concordance of LDL-cholesterol with regard to treatment group classification based on population-equivalent thresholds of apoB in hypertriglyceridemic patients (2-4.5 mmol/L), with the highest concordance (75.6%) obtained using Martin-Hopkins formula vs. 60.5% with Friedewald formula.ConclusionThe Martin-Hopkins (and, to a lesser extent, Sampson) formula is more closely associated with the number of LDL particles than Friedewald formula. This, in combination with literature evidence of lesser accuracy of the Friedewald formula, is an argument to switch from Friedewald to a modified, improved formula.  相似文献   
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The aim of present study was to examine the relationships between serum and salivary values of free testosterone, dehydroepiandrosterone, and cortisol before and after a session of resistance exercise. Twenty-eight healthy men (mean age 40 years, s = 4) participated in the present study. Serum and salivary samples were collected at rest and after a multiple-sets resistance exercise protocol, of approximately 25 minutes duration. Concentrations of free testosterone, dehydroepiandrosterone, and cortisol were measured using radioimmunoassay kits. No significant correlation was observed between serum free testosterone and salivary testosterone (r = 0.22 to 0.26, P > 0.05). Serum cortisol was significantly correlated with salivary cortisol before (r = 0.52, P = 0.005) and after (r = 0.62, P = 0.001) the exercise protocol. Serum and salivary concentrations of dehydroepiandrosterone were significantly correlated before (r = 0.68, P < 0.001) and after (r = 0.7, P < 0.001) exercise. The results of the present study suggest that even under exercise conditions, the salivary values of cortisol and dehydroepiandrosterone can reflect the behaviour of these hormones in blood. However, further studies are necessary to verify if salivary testosterone reflects the behaviour of serum free testosterone during resistance exercise.  相似文献   
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Abstract

This article discusses the application of digital video to multimedia, and looks at the pros and cons of two different approaches. It also considers the standards of equipment for various uses.  相似文献   
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Unlike some pivotal ideas in the history of science, the basic notion of natural selection is remarkably simple and so one might expect most students to easily grasp the basic principles of the Darwinian theory; yet many students nevertheless have difficulty understanding Darwinian evolution. We suggest that misconceptions about natural selection arise from mistaken categorization. Our thesis for explaining students’ failure to understand this concept or evolution in general is not that they necessarily fail to understand individual Darwinian principles; rather, they often fail to understand the ontological features of equilibration processes, of which evolution is one instance. They thus attribute the evolutionary process in general, and natural selection in particular, with event‐like properties. For example, naive students appear to focus on the idea of survival of the fittest, but embed this idea within an event ontology that involves actors struggling to overcome obstacles and achieve goals. Results showed that most naive subjects’ evolutionary explanations reflected an event ontology. Furthermore, event ontology attributes were positively correlated with non‐Darwinian explanations; by contrast, equilibration attributes, when present, were positively correlated with key Darwinian principles. These findings suggest that students would greatly benefit from science instruction that emphasized the underlying ontology of modern evolutionary theory.  相似文献   
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