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Operating characteristics of the Center for Epidemiologic Studies Depression Scale (CES-D) were examined by using data from 4 samples of students in Grades 9–12. The CES-D was found to have good internal consistency and test–retest reliability. Dimensionality was comparable to that found for adults. Structure varied little by order of assessment (Trial 1 of Trial 2), age, or gender. Salience of items, in terms of rank order of mean item scores, was remarkably similar to that reported for college and general adult samples. With the standard cutoff score of 16 or more, half of the high school students were classified as depressed. There was a pronounced gender effect, with proportionately more women reporting depressive symptoms across the 4 samples. Although it appears that the CES-D scale may be appropriate for use with adolescents, the issues of stability of scores over time, appropriate cutoff scores, and usefulness in detecting cases of clinical depression remain unresolved. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Ultrathin strained-Si/strained-Ge heterostructures on insulator have been fabricated using a bond and etch-back technique. The substrate consists of a trilayer of 9 nm strained-Si/4 nm strained-Ge/3 nm strained-Si on a 400-nm-thick buried oxide. The epitaxial trilayer structure was originally grown pseudomorphic to a relaxed Si0.5Ge0.5 layer on a donor substrate. Raman analysis of the as-grown and final transferred layer structures indicates that there is little change in the strain in the Si and Ge layers after layer transfer. These ultrathin Si and Ge films have very high levels of strain (∼1.8% biaxial tension and 1.4% compression, respectively), and are suitable for enhanced-mobility field-effect transistor applications.  相似文献   
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In this study the effects of CCK microinjections into the rostral or caudal nucleus accumbens (Acc) on locomotor activation derived from systemic amphetamine treatment were examined. It was found that CCK microinjections into the rostral Acc attenuated and CCK microinjections into the caudal Acc potentiated amphetamine-induced locomotor activity. Results indicate that rostral Acc CCK microinjections have dopamine agonistlike effects on amphetamine-induced locomotor activity. The relevance of the present findings to previous results regarding CCK–dopamine interactions is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The primary objective of the experiments reported here was to demonstrate the effects of opening up the design envelope for auditory alarms on the ability of people to learn the meanings of a set of alarms. Two sets of alarms were tested, one already extant and one newly-designed set for the same set of functions, designed according to a rationale set out by the authors aimed at increasing the heterogeneity of the alarm set and incorporating some well-established principles of alarm design. For both sets of alarms, a similarity-rating experiment was followed by a learning experiment. The results showed that the newly-designed set was judged to be more internally dissimilar, and easier to learn, than the extant set. The design rationale outlined in the paper is useful for design purposes in a variety of practical domains and shows how alarm designers, even at a relatively late stage in the design process, can improve the efficacy of an alarm set.  相似文献   
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BACKGROUND: Soybean seeds are rich in natural protein and are favorable environments for targeted protein expression. Soybeans represent an ideal platform for the production of novel vaccines that, in theory, do not require a cold chain. This study investigated the stability of a soybean‐derived antigen following long‐term storage, formulation, and shipment overseas in the absence of refrigeration. RESULTS: Transgenic seeds can be stored for more than 4 years at ambient temperature with no detectable loss of FanC antigen stability. Conventional processing methods utilizing heat, mechanical extraction and solvent extraction resulted in practical formulations that could be lyophilized, stored as dried milk powder and rehydrated in water without loss of FanC antigen stability. Overseas shipment of transgenic seed powder and soymilk formulations in the absence of a cold chain had no adverse effects on formulations or the FanC antigen. CONCLUSION: The feasibility of long‐term storage, processing and shipment of transgenic soy products in the absence of a cold chain was demonstrated. Soybeans represent a practical platform for development of novel vaccines to potentially address the worldwide need for vaccines that are cost‐effective, easy to formulate and can be manufactured, stored and transported without refrigeration. Copyright © 2009 Society of Chemical Industry  相似文献   
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The restoration of body contours as shaped by adipose tissue remains a clinical challenge specifically in patients who have experienced loss of contour due to trauma, surgical removal of tumours or congenital abnormalities. We have developed a novel macro-microporous biomaterial for use in soft tissue re-bulking and augmentation. Alginate beads provided the pore template for the construct. Incorporation, and subsequent dissolution, of the beads within a 7 % (w/v) gelatin matrix, produced a highly porous scaffold with an average pore size of 2.01 ± 0.08 mm. The ability of this scaffold to support the in vitro growth and differentiation of human adipose-derived stem cells (ADSCs) was then investigated. Histological analysis confirmed that the scaffold itself provided a suitable environment to support the growth of ADSCs on the scaffold walls. When delivered into the macropores in a fibrin hydrogel, ADSCs proliferated and filled the pores. In addition, ADSCs could readily be differentiated along the adipogenic lineage. These results therefore describe a novel scaffold that can support the proliferation and delivery of ADSCs. The scaffold is the first stage in developing a clinical alternative to current treatment methods for soft tissue reconstruction.  相似文献   
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