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1.
A meta-analysis of 47 studies was used to shed light on inconsistencies in the concurrent association between parental caregiving and child externalizing behavior. Parent–child associations were strongest when the measure of caregiving relied on observations or interviews, as opposed to questionnaires, and when the measure tapped combinations of parent behaviors (patterns), as opposed to single behaviors. Stronger parent–child associations were also found for older than for younger children, and for mothers than for fathers. Finally, externalizing was more strongly linked to parental caregiving for boys than for girls, especially among preadolescents and their mothers. The meta-analysis helps account for inconsistencies in findings across previous studies and supports theories emphasizing reciprocity of parent and child behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
The function of acidification along the endocytic pathway is not well understood, in part because the perturbants used to modify compartmental pH have global effects and in some cases alter cytoplasmic pH. We have used a new approach to study the effect of pH perturbation on postendocytic traffic in polarized Madin-Darby canine kidney (MDCK) cells. Influenza M2 is a small membrane protein that functions as an acid-activated ion channel and can elevate the pH of the trans-Golgi network and endosomes. We used recombinant adenoviruses to express the M2 protein of influenza virus in polarized MDCK cells stably transfected with the polymeric immunoglobulin (Ig) receptor. Using indirect immunofluorescence and immunoelectron microscopy, M2 was found to be concentrated at the apical plasma membrane and in subapical vesicles; intracellular M2 colocalized partly with internalized IgA in apical recycling endosomes as well as with the trans-Golgi network marker TGN-38. Expression of M2 slowed the rate of IgA transcytosis across polarized MDCK monolayers. The delay in transport occurred after IgA reached the apical recycling endosome, consistent with the localization of intracellular M2. Apical recycling of IgA was also slowed in the presence of M2, whereas basolateral recycling of transferrin and degradation of IgA were unaffected. By contrast, ammonium chloride affected both apical IgA and basolateral transferrin release. Together, our data suggest that M2 expression selectively perturbs acidification in compartments involved in apical delivery without disrupting other postendocytic transport steps.  相似文献   
3.
An array of perfectly alternating polycarbonate‐polydimethylsiloxane (PC‐PDMS) multiblock copolymers possessing systematic variations in block molecular weights were successfully produced by coupling preformed PC and PDMS telechelic oligomers using hydrosilylation. Based on gel permeation chromatography results, the multiblock copolymers were essentially void of the oligomeric precursors. Despite the relatively large difference in solubility parameter between PC and PDMS, the multiblock copolymers exhibited significant partial miscibility between the two phases. As expected, the degree of partial miscibility was dependent on the molecular weight of the blocks with the extent of partial miscibility increasing with decreasing block molecular weights. Morphological characterization using small angle X‐ray scattering showed that, at a given PC block molecular weight, the uniformity of the two phase morphology increased with increasing PDMS block molecular weight, which is consistent with a decrease in the extent of phase mixing with increasing PDMS block molecular weight. POLYM. ENG. SCI., 54:1648–1663, 2014. © 2013 Society of Plastics Engineers  相似文献   
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Administered the Stanford-Binet Intelligence Scale short form, J. Wright's (1973) measure of impulsivity-reflectivity (IR), and a measure hypothesis behavior to 102 preschoolers. Results show that mental age was more appropriate than IQ as an index of developmental variance in IR. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
An approach using spatial analysis of satellite IR spectral measurements for quality assessment is presented. The second spatial differential is used as a model of measurement noise for spatially smooth radiative fields. Spatial differentiation significantly magnifies the noise contribution and reduces the physical signal amplitude because of differences in spatial distributions of instrument noise and atmospheric thermal fields. The second spatial differential represents a convenient and effective tool for numerical analysis of satellite IR measurements. This paper demonstrates that statistics of the second spatial differential are informative predictors for data‐quality characterization. Statistics of the second spatial differential are used for identifying anomalies in spectral channel data caused by detector noise, sensitivity loss to spatial shortwave thermal variations, and spatially (temporally) correlated noise.  相似文献   
7.
Do clinic-referred children and their parents agree on the problems for which treatment is undertaken? The authors asked 381 outpatient-clinic-referred children and their parents to list, independently, the child's target problems. Of the parent-child pairs, 63 % failed to agree on even a single problem. When problems were grouped into broad categories (e.g., delinquent, withdrawn), more than a third of the pairs still failed to agree on a single broad problem area. Parent-child agreement was higher for externalizing than for internalizing problem categories (though poor for both). Low parent-child agreement may help explain the poor outcomes often reported for clinic-based child therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
Most empirically supported interventions for adolescent mental health problems are either downward adaptations of adult treatments or upward adaptations of child treatments. Although these treatments show respectable effects with teens, a review of the outcome research reveals significant gaps, both in coverage of adolescent conditions and problems (e.g., eating disorders, suicidality) and in attention to the biological, psychological, and social dimensions of adolescent development. The authors critique the field, propose a biopsychosocial framework for the development of dysfunction and intervention, and discuss ways the developmental literature can and cannot inform intervention and research. A long-term goal is an array of developmentally tailored treatments that are effective with clinically referred teens and an enriched understanding of when, how, and why the treatments work. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
The contingency–competence–control (CCC) model links contingency and competence beliefs to perceived control and, in turn, to depression. However, a developmental perspective suggests that noncontingency may be too abstract a concept to be directly tied to depression before adolescence. We tested the CCC model and this developmental notion, using structural equation modeling, with 360 clinic-referred 8- to 17-year-olds. The CCC model fit the data well for the full sample accounting for 46% of the variance in depression. Separate analyses by age group placed perceived contingency in the best-fit model for adolescents (ages 12–17 years) but not for children (8–11 years). This suggests that abstract cause–effect concepts may have more direct affective impact after the cognitive changes of adolescence (e.g., formal operations) than before. Finally, the CCC model accounted for much more variance in depression than conduct problems, suggesting diagnostic specificity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Child behavior problems and corresponding clinic referral patterns may be significantly influenced by cultural factors. Prevailing values and childrearing practices within a culture may discourage development of some child problems while fostering others. We explored this possibility, focusing on clinic referral problems of two different societies: (a) Jamaica, where the Afro-British culture discourages child aggression and other undercontrolled behavior and possibly fosters inhibition and other overcontrolled behavior, and (b) the United States, where undercontrolled child behavior is seemingly more generally accepted. We coded clinic-referred problems listed by parents of Jamaican and American youngsters (N?=?720). Cross-cultural differences were striking: Overcontrolled problems were noted more often for Jamaican than American youngsters, whereas the converse was true for uncontrolled problems. These and other findings suggest that factors such as culture and sex may be linked to substantial differences in the problems for which youngsters of different countries are treated in clinics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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