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371.
Research note     
Conclusions The results of the present study seem to justify the following conclusions: (1) it is possible to identify several, relatively independent, and psychologically meaningful dimensions of the self-concept; and (2) the self-concept as measured by the Self-concept Scale functions independently of intelligence and academic aptitude as a correlate of academic achievement. Therefore, the new instriument has opotential to make an important contribution to the prediction of academic achievement. Since the istrument is only in its experimental stage, replication and cross-validation studies should be carried out to confirm the findings of the study.OISEBased mainly on Gill (1968).  相似文献   
372.
Objectives: To devise and evaluate a sensitive search strategy to retrieve diagnostic studies on specific diagnostic tests for deep vein thrombosis (DVT). Methods: Systematic reviews on diagnostic tests for DVT were identified and the studies cited by them used to produce a reference set of search results (to be used to evaluate different search strategies). Five existing diagnosis search filters were combined to produce a sensitive search. This combined search was then refined to produce a more specific strategy, which was run on medline and the results were checked against the reference set. This search was too specific and was modified to produce a more balanced final strategy, which was again tested and the results compared with the reference set. The sensitivity of this newly created strategy was compared with the existing diagnosis searches already found. Finally, studies identified by the final search strategy were critically appraised for validity and relevance and the selected articles were compared with those found in the reference set. Results: The final filter retrieved 124 out of 126 references from the reference set. From the search result, 227 cohort studies were selected and 147 of these were not cited in any of the systematic reviews on diagnostic tests for DVT. Conclusions: The search strategy had 98.8% sensitivity. The precision of 8.8%, although low, compares well with other strategies with high sensitivity. Most of the systematic reviews on diagnosing a DVT have omitted a number of high quality articles.  相似文献   
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Recent research on education and occupational attainment has opened up new areas for study. Employing the bilateral or segmented theory of labor markets, this research has begun to reveal both the complexity and variability of schooling's impact upon the diverse work careers of differing groups in society. Specific attention is paid to recent studies of the effect of educational origins upon the work careers of individuals in professional and business—managerial occupations in the United States. Among professional occupations not only do college origins matter but their impact is greater among graduates of low social status backgrounds than among those of high status origins. Implications for our understanding of the role of higher education in social stratification is explored with specific reference to current theories of educational sponsorship.  相似文献   
377.
ABSTRACT

This experimental program, implemented by the Managing Collection Environment Initiative at the Getty Conservation Institute, has provided data about the response of historic objects to changes in relative humidity (RH). Alongside other less sensitive documentation techniques (visual observation, physical measurements, photography, and 3D scanning), acoustic emission (AE) was monitored for six historic, museum-like wooden objects exposed to gradually increasing RH variations. Quantitative calibration of AE sensors and an anti-correlation measuring scheme to reduce environmental noise allowed the AE system to effectively trace micro-damage development caused by environmentally induced stress. Using an epidemiological approach, with respect to sample selection and experimental protocol, the obtained results can be used to explore the acceptable range of climate fluctuations for museum collections. The study’s well-controlled environmental protocol also allowed for the examination of the concept of ‘proofed fluctuation’ by the analysis of object response to reoccurring conditions.  相似文献   
378.
Editor's Note: The following is adapted from a letter and accompanying essay that were sent to each of the regents of the University of California at the close of the spring semester, 1990, by Prof. Sarich.  相似文献   
379.
Biotechnology is an emergent sector based on the creation of research-intensive Small and Medium Enterprises (SMEs). While some SMEs are growing, most of them remain small, even those set-up several years ago. What is the pattern of development of the biotech sector? What are the patterns of development of firms? Studies on the development of high-tech SMEs have focused on a business model, in which entrepreneurs rely on growth forecasts to persuade capital investors (business angels and venture capitalists) to invest in a radical innovation project. Firms aim for a world market to industrialise their innovation, and initial public offering (IPO) enables initial investors to make profits that offset risky initial investment. While this model is appealing, it is simply one of the possible models of biotechnology development. Some firms are not designed to experience exponential growth, and choose to target local markets. Moreover, not all firms have the ambition of being listed on the stock exchange. Based on an in-depth analysis of the business and development of 60 French biotech SMEs, this article identifies two business models. By defining the development trajectories of each of these models, it highlights the temporary nature of the emergent model.  相似文献   
380.
DOES THE SCHOOL COMPOSITION EFFECT MATTER? EVIDENCE FROM BELGIAN DATA   总被引:2,自引:1,他引:1  
ABSTRACT:  Even if the literature on the effects of pupil composition has been extensive, no clear consensus has been reached concerning the significance and magnitude of this effect. The first objective of this article is to estimate the magnitude of the school composition effect in primary schools (6th grade) in French-speaking Belgium. Different indicators of school composition are used: academic, socio-cultural, 'language' and sex composition. Except for sex composition, the results show that the school composition effect explains significant amount of between schools variance even after controlling for pupils' initial performance, socio-cultural background, and non-cognitive dispositions. The second objective is to examine covariance between school composition and several organisational variables and their joint effect on school performance. The second set of analyses is intended to question the conceptual nature of the school composition effect, establishing whether it is direct or indirect.  相似文献   
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