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Background: Search filters have been developed in MEDLINE and EMBASE to help overcome the challenges of searching electronic databases for information on adverse effects. However, little evaluation of their effectiveness has been carried out. Objectives: To measure the sensitivity and precision of available adverse effects search filters in MEDLINE and EMBASE. Methods: A case study systematic review of fracture related adverse effects associated with the use of thiazolidinediones was used. Twelve MEDLINE search strategies and three EMBASE search strategies were tested. Results: Nineteen relevant references from MEDLINE and 24 from EMBASE were included in the review. Four search filters in MEDLINE achieved high sensitivity (95 or 100%) with an improved level of precision from searches without any adverse effects filter. High precision in MEDLINE could also be achieved (up to 53%) using search filters that rely on Medical Subject Headings. No search filter in EMBASE achieved high precision (all were under 5%) and the highest sensitivity in EMBASE was 83%. Conclusions: Adverse effects search filters appear to be effective in MEDLINE for achieving either high sensitivity or high precision. Search filters in EMBASE, however, do not appear as effective, particularly in improving precision.  相似文献   
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In testing the factorial invariance of a measure across groups, the groups are often of different sizes. Large imbalances in group size might affect the results of factorial invariance studies and lead to incorrect conclusions of invariance because the fit function in multiple-group factor analysis includes a weighting by group sample size. The implication is that violations of invariance might not be detected if the sample sizes of the 2 groups are severely unbalanced. In this study, we examined the effects of group size differences on results of factorial invariance tests, proposed a subsampling method to address unbalanced sample size issue in factorial invariance studies, and evaluated the proposed approach in various simulation conditions. Our findings confirm that violations of invariance might be masked in the case of severely unbalanced group size conditions and support the use of the proposed subsampling method to obtain accurate results for invariance studies.  相似文献   
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The primary purpose of the current research was to identify core contextual factors that facilitate or hinder the process of organizational knowledge creation practices. The grounded theory framework and negotiated coding approach were employed. Serving as the fundamental research framework was Nonaka and his colleagues' knowledge creation and conversion theory, along with their proposed knowledge creation enablers. A total of 314 codeable units from 153 individuals were used for data analysis. All answers were coded and categorized into three emerged domains—organization, team/subgroup, and individual—for both areas of facilitating and hindering factors. Limitations and implications for further research are presented in the discussion section.  相似文献   
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Although it is well established that Black male students are underrepresented in gifted educational programs in the United States, due to a scarcity of longitudinal prospective research, little is known about the protective factors at the child, family, and school level that increase the probability of Black male students being identified as gifted during early elementary school. Using data from the Miami School Readiness Project, we followed 6,926 low-income Black males from preschool through 5th grade to describe trajectories for the 453 Black males (6.5 %) who were identified as gifted, and examined child, family, and preschool variables associated with gifted classification. Boys were most commonly identified as gifted in first and second grade, and 15 % of the identified boys did not appear to be receiving gifted courses. Hierarchical multiple logistic regression analyses revealed that being classified as gifted in early elementary school was more likely for Black males who (a) attended public school pre-K programs at age four, (b) had higher cognitive, language, fine motor, behavioral, and emergent literacy school readiness skills before entering kindergarten, (c) spoke a language other than English at home, (d) were older upon entering kindergarten, (e) received higher grades in school, and (f) scored higher on standardized tests of math and reading. Predictors of gifted identification in the kindergarten year were different and weaker compared to identification in later years. Implications for early identification and intervention for talented Black males are discussed.  相似文献   
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A Multicultural Counseling course (MCC) brings unique challenges and rewards to both instructors and students. Given its unique challenges, the process of teaching a MCC is as important as, or even more important than, the content. Drawing from extant literature and the authors’ experiences, this paper discusses such topics as what to teach, how to teach, classroom dynamics, instructors’ issues, and students’ issues to provide a concise, practical, and comprehensive framework for teaching such difficult but essential courses.  相似文献   
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Optoelectrofluidic field separation (OEFS) of particles under light -intensity gradient (LIG) is reported, where the LIG illumination on the photoconductive layer converts the short-ranged dielectrophoresis (DEP) force to the long-ranged one. The long-ranged DEP force can compete with the hydrodynamic force by alternating current electro-osmosis (ACEO) over the entire illumination area for realizing effective field separation of particles. In the OEFS system, the codirectional illumination and observation induce the levitation effect, compensating the attenuation of the DEP force under LIG illumination by slightly floating particles from the surface. Results of the field separation and concentration of diverse particle pairs (0.82–16 μm) are well demonstrated, and conditions determining the critical radius and effective particle manipulation are discussed. The OEFS with codirectional LIG strategy could be a promising particle manipulation method in many applications where a rapid manipulation of biological cells and particles over the entire working area are of interest.  相似文献   
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In practical text classification tasks, the ability to interpret the classification result is as important as the ability to classify exactly. Associative classifiers have many favorable characteristics such as rapid training, good classification accuracy, and excellent interpretation. However, associative classifiers also have some obstacles to overcome when they are applied in the area of text classification. The target text collection generally has a very high dimension, thus the training process might take a very long time. We propose a feature selection based on the mutual information between the word and class variables to reduce the space dimension of the associative classifiers. In addition, the training process of the associative classifier produces a huge amount of classification rules, which makes the prediction with a new document ineffective. We resolve this by introducing a new efficient method for storing and pruning classification rules. This method can also be used when predicting a test document. Experimental results using the 20-newsgroups dataset show many benefits of the associative classification in both training and predicting when applied to a real world problem.  相似文献   
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We present an engineered three-dimensional (3D) in vitro brain microvasculature system embedded within the bulk of a collagen matrix. To create a hydrogel template for the functional brain microvascular structure, we fabricated an array of microchannels made of collagen I using microneedles and a 3D printed frame. By culturing mouse brain endothelial cells (bEnd.3) on the luminal surface of cylindrical collagen microchannels, we reconstructed an array of brain microvasculature in vitro with circular cross-sections. We characterized the barrier function of our brain microvasculature by measuring transendothelial permeability of 40 kDa fluorescein isothiocyanate-dextran (Stoke''s radius of ∼4.5 nm), based on an analytical model. The transendothelial permeability decreased significantly over 3 weeks of culture. We also present the disruption of the barrier function with a hyperosmotic mannitol as well as a subsequent recovery over 4 days. Our brain microvasculature model in vitro, consisting of system-in-hydrogel combined with the widely emerging 3D printing technique, can serve as a useful tool not only for fundamental studies associated with blood-brain barrier in physiological and pathological settings but also for pharmaceutical applications.  相似文献   
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