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71.
[Correction Notice: An erratum for this article was reported in Vol 103(3) of Psychological Bulletin (see record 2008-10688-001). Tables 1 and 2 contain several errors. The correct data is provided in the erratum. These errors do not influence any of the main points or conclusions in this article.] Obesity is a common problem in children and is associated with an increased risk of adult obesity. Twenty-four studies on the behavioral treatment of childhood obesity are reviewed. Studies involving comparisons of behavioral treatment with no treatment or placebos have shown the superiority of behavioral treatment. In addition, the effects of a number of treatment factors on outcome are suggested. These factors include parental involvement, the arrangement of treatment contingencies, and exercise. Several directions for future research are presented, including selecting which children to treat, individualizing treatment, prevention, community programs, and the side effects of weight control. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
72.
Two-year follow-up data (from inner-city, minority adolescents) were collected to test the effectiveness of 2 skills-based substance abuse prevention programs and were compared both with a control condition and with each other. Students were originally recruited from 6 New York City public schools while in 7th grade. Schools were matched and assigned to receive a generic skills training prevention approach, a culturally focused prevention approach, or an information-only control. Students in both prevention approaches had less current alcohol use and had lower intentions to engage in future alcohol use relative to students in the control group. Students in the culturally focused group also engaged less in current alcohol behavior and had lower intentions to drink beer or wine than those in the generic skills group. Both prevention programs influenced several mediating variables in a direction consistent with nondrug use, and these variables also mediated alcohol use. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
73.
Analyzed the effects of family variables (e.g., family size, family weight composition, parental weight) on child weight loss in a series of family-based, behaviorally oriented weight control programs for children from 102 families. Results show that the amount of relative weight change was related to initial treatment success, the number of children in the family, and the gender of the child. Children who were more successful lost more weight initially, had fewer siblings, and were female. It is suggested that family size may interact with treatment to determine weight change, possibly by reducing the amount of time a parent has to spend promoting behavior change or the effectiveness of parents in managing their children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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75.
We describe the growth of modulation-doped ZnSe/(Zn,Cd)Se quantum wells on (110) GaAs substrates. Unlike the well-known protocol for the epitaxy of ZnSe-based quantum structures on (001) GaAs, we find that the fabrication of quantum well structures on (110) GaAs requires significantly different growth conditions and sample architecture. We use magnetotransport measurements to confirm the formation of a two-dimensional electron gas in these samples, and then measure transverse electron spin relaxation times using time-resolved Faraday rotation. In contrast to expectations based upon known spin relaxation mechanisms, we find surprisingly little difference between the spin lifetimes in these (110)-oriented samples in comparison with (100)-oriented control samples.  相似文献   
76.
Investigated the psychometric properties of the McMaster Family Assessment Device (FAD [N. Epstein et al; see PA, Vol 71:2891]), a multidimensional measure of family functioning, using data from psychiatric (n?=?1,138), nonclinical (n?=?627), and medical (n?=?298) samples. Internal scale reliabilities and factorial validity were assessed for each group, and results were compared across groups. In general, scale reliabilities were favorable and the hypothesized factor structure of the FAD was supported. Results also support the use of the 60-item version over the original 53-item version. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Boron has been proposed as a candidate for hydrogen production. In this study a process is described in which boron is used as a means to store and transport solar energy from a production site to motor vehicles, where it is used to generate hydrogen and heat. The proposed multi-step fuel cycle includes no carbon as a reducing agent and, therefore, no release of CO2 to the atmosphere. This process is safe, mostly involving harmless materials and well-understood technologies. It eliminates the distribution, storage, and pumping of hydrogen at the refueling station, and diminishes the amount of hydrogen stored on the vehicle to a minimum. It is shown that the boron reaction with water, performed on-board of a vehicle, has high hydrogen storage capacity based on both volume and mass, compared with other candidate technologies. An energy balance of the entire process predicts that the overall efficiency of converting solar energy to work by the vehicle engine can be about 11%.  相似文献   
79.
Moiré interferometry was used for direct measurements of the crack tip behavior in the homogeneous compact tension (CT) specimens of A533B and HT80 steels, and in electron-beam welded inhomogeneous CT specimens of the two materials. These two materials have considerably different yield stresses, although their elastic properties are the same. Five types of homogeneous and inhomogeneous specimens were used in the experiment. Moiré fringe patterns of the five specimen types were directly compared for elastic, elastic-plastic and unloaded stages. Although the global deformations in terms of the load versus COD relations exhibit little inhomogeneity effects, large inhomogeneity effects were observed in the moiré fringe patterns in the elastic-plastic and unloaded stages. The near-tip deformations were also compared with the corresponding HRR singular fields. In a horizontal weld specimen, due to strong hardening in the weld region, the slope of the displacement field does not shift the characteristic HRR field for the A533B or the HT80 steel for increasing load.  相似文献   
80.
A single sodium depletion enhances the salt appetite that is expressed after a second and subsequent sodium depletions. The enhanced salt intake, as measured by a decrease in latency to drink and an increase in volume of 3% NaCl ingested, is not accounted for by an increased sodium loss. The enhanced salt intake occurs even when the interval between first and second depletion is as long as 4 months. The enhanced salt appetite does not depend on the drinking of salt after the animal's first sodium depletion and is specific for strong 0.52 M NaCl but not for 0.52 M KCl. Moreover, it can be produced without sodium depletion by the actions of the hormones aldosterone and angiotensin on the brain. These results suggest that angiotensin and aldosterone, which are released in response to sodium depletion, (a) increase renal sodium conservation, (b) evoke a salt appetite to restore the lost sodium, and (c) produce enduring changes in the brain that prepare it for more rapid and more vigorous expression of salt appetite in response to future sodium depletions. Thus the neural mechanisms that govern salt appetite are not only activated by the hormones of sodium conservation but appear also to be organized by them for a lifelong increase in avidity for salty substances. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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