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121.
This study examined an important but rarely investigated aspect of the dissemination process: the intensity of training provided to practitioners. Counselors in 57 schools were randomly assigned to 1 of 3 conditions: Coping Power–training plus feedback (CP-TF), Coping Power–basic training (CP-BT), or a comparison condition. CP-TF counselors produced reductions in children’s externalizing behavior problems and improvements in children’s social and academic skills in comparison to results for target children in both the comparison and the CP-BT conditions. Training intensity was critical for successful dissemination, although the implementation mechanism underlying this effect remains unclear, as condition effects were not significant for completion of session objectives but were significant for the quality of counselors’ engagement with children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
122.
Functionalized gold nanoparticles have been covalently bound to internal, modified sites on double-stranded DNA. Gold nanoparticles coated with mercaptosuccinic acid or thioctic acid were bound to amino-modified thymine bases on double-stranded DNA. Visible absorption spectra, gel electrophoresis, and atomic force microscopy were used to analyze the products. Thiol groups were added to one end of the gold/nanoparticle product, which was then attached to a gold surface. This method has the potential to allow controlled placement of particles with subnanometer precision and to allow attachment of the product to fixed contacts for nanodevice fabrication.  相似文献   
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In the early adoption phase of business-to-consumer (B2C) ecommerce, the tasks that proved most conducive to online consumer interaction typically were goal-directed, being clear in sequence and structure. A key challenge in ecommerce is the ability to design interfaces that support experiential tasks in addition to goal-directed tasks. Most of the ecommerce research on interface design, however, has focused on goal-directed tasks and has not addressed experiential tasks. Based on the literature from interface metaphors and mental models, this paper explores the use of tangible attributes derived from the physical business domain as a technique for designing an interface that effectively supports experiential tasks. A laboratory experiment was designed and conducted to test the impact of two types of interfaces and business domain familiarity when completing an experiential task. Because consumers need to retain and recall information to evaluate products/services or to make brand associations, retention/recall of information was measured on both the day of the treatment and after a 2-day lag. Results revealed that the interface based upon the business domain metaphor stimulated higher levels of retention and recall of information and thus provided the desired support for experiential tasks. Further, users with weaker domain familiarity showed the greatest improvement in retention and recall, particularly after a 2-day lag, when using the interface with the business domain metaphor design.  相似文献   
124.
Localization ROC (LROC) observer studies examined whether detector response compensation (DRC) in ordered-subset, expectation-maximization (OSEM) reconstructions helps in the detection and localization of hot tumors. Simulated gallium (Ga-67) images of the thoracic region were used in the study. The projection data modeled the acquisition of attenuated 93- and 185-keV photons with a medium-energy parallel-hole collimator, but scatter was not modeled. Images were reconstructed with five strategies: 1) OSEM with no DRC; 2) OSEM preceded by restoration filtering; 3) OSEM with iterative DRC; 4) OSEM with an ideal DRC; and 5) filtered backprojection (FBP) with no DRC. All strategies included attenuation correction. There were four LROC studies conducted. In a study using a single tumor activity, the ideal DRC offered the best performance, followed by iterative DRC, restoration filtering, OSEM with no DRC, and FBP. Statistical significance at the 5% level was found between all pairs of strategies except for restoration filtering and OSEM with no DRC. A similar ranking was found for a more realistic study using multiple tumor activities. Additional studies considered the effects of OSEM iteration number and tumor activity on the detection improvement that iterative DRC offered with respect to OSEM with no DRC.  相似文献   
125.
Comments on M. McCloskey and H. E. Egeth's (see record 1984-06612-001) argument that psychologists should not give expert testimony concerning eyewitness reliability on the basis of psychological findings on perception and memory. The present author discusses the importance of process issues in legal situations and contests McCloskey and Egeth's conclusions concerning "overbelief" of eyewitness accuracy. (5 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Leptin, the protein product of the adipose tissue-specific ob (obese) gene (1), reduces the body weight, adiposity and food intake of obese ob/ob mice on peripheral or central injection (2, 3, 4). [125I]leptin binding has been detected in mouse choroid plexus (5), from which a leptin receptor gene was expression cloned (5). The gene has at least 6 splice variants (6, 7). Leptin receptor mRNA was localized in the hypothalamus by in situ hybridization being particularly abundantly expressed in the arcuate nucleus (8). There is evidence linking the physiological effects of injected leptin with hypothalamic neuropeptide Y (9, 10) (NPY), which has potent central effects on food intake and energy balance (11), and is also expressed in the arcuate nucleus. Here we report dual in situ hybridization studies for leptin receptor and NPY gene expression in the mouse arcuate nucleus, where the majority of cells examined expressed both genes. This provides the first direct evidence that leptin acts on cells that express NPY mRNA.  相似文献   
129.
The objectives of this study were to quantify the effectiveness of dietary retinol sources, orange fruit, and dark-green, leafy vegetables in improving vitamin A status, and to test whether orange fruit is a better source of vitamin A and carotenoids than are leafy vegetables. Anemic schoolchildren aged 7-11 y (n = 238) in West Java, Indonesia, were randomly allocated to 1 of 4 groups to consume 2 complete meals/d, 6 d/wk, for 9 wk: 1) 556 retinol equivalents (RE)/d from retinol-rich food (n = 48); 2) 509 RE/d from fruit (n = 49); 3) 684 RE/d from dark-green, leafy vegetables and carrots (n = 45); and 4) 44 RE/d from low-retinol, low-carotene food (n = 46). Mean changes in serum retinol concentrations of the retinol-rich, fruit, vegetable, and low-retinol, low-carotene groups were 0.23 (95% CI: 0.18, 0.28), 0.12 (0.06, 0.18), 0.07 (0.03,0.11), and 0.00 (-0.06, 0.05) micromol/L, respectively. Mean changes in serum beta-carotene concentrations in the vegetable and fruit groups were 0.14 (0.12, 0.17) and 0.52 (0.43, 0.60) micromol/L, respectively. Until now, it has been assumed that 6 microg dietary beta-carotene is equivalent to 1 RE. On the basis of this study, however, the equivalent of 1 RE would be 12 microg beta-carotene (95% CI: 6 microg, 29 microg) for fruit and 26 microg beta-carotene (95% CI: 13 microg, 76 microg) for leafy vegetables and carrots. Thus, the apparent mean vitamin A activity of carotenoids in fruit and in leafy vegetables and carrots was 50% (95% CI: 21%, 100%) and 23% (95% CI: 8%, 46%) of that assumed, respectively. This has important implications for choosing strategies for controlling vitamin A deficiency. Research should be directed toward ways of improving bioavailability and bioconversion of dietary carotenoids, focusing on factors such as intestinal parasites, absorption inhibitors, and food matrixes.  相似文献   
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