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21.
The Skinny on Body Dissatisfaction: A Longitudinal Study of Adolescent Girls and Boys 总被引:3,自引:1,他引:3
The present study tested whether theoretically derived risk factors predicted increases in body dissatisfaction and whether gender moderated these relations with data from a longitudinal study of 428 adolescent girls and boys because few prospective studies have examined these aims, despite evidence that body dissatisfaction increases risk for various psychiatric disturbances. Body dissatisfaction showed significant increases for girls and significant decreases for boys during early adolescence. For both genders, parental support deficits, negative affectivity, and self-reported dietary restraint showed significant relations to future increases in body dissatisfaction. Ideal body internalization and body mass index did not demonstrate significant relations to future increases in body dissatisfaction; peer support deficits showed a marginal relation to this outcome. Gender did not moderate these relations, despite adequate power to detect interactive effects.
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Sarah Kate BearmanEmail: |
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Efficient capillary electrophoretic STR analysis requires rapid, reproducible and robust separation of DNA fragments with reasonable capillary longevity--this is currently accomplished using proprietary commercial polymeric sieving matrices specifically developed for this separation. These matrices, while effective, are costly and do not provide adequate resolution of STR DNA fragments in capillaries with shorter effective separation lengths, increasing the time required to accomplish the separation and minimizing the potential extrapolation to other miniaturized platforms. As the forensic community looks toward next generation microchip technology as a means of processing casework more rapidly, new sieving polymers need to be evaluated for utilization in this platform. The research presented here describes the assessment of commercially-available polymeric sieving matrices for STR analysis, with consideration given to feasibility of incorporation into a microdevice. Polymer composition, molecular weight, and concentration were evaluated, along with an assessment of the effects of buffer composition, separation temperature, and capillary length. These variables were evaluated individually or collectively on the ability to resolve STR DNA fragments and the reproducibility of the separations and the results compared to a proprietary commercial product. A 600,000 Da MW poly(ethylene oxide) (PEO) solution at a 3% (w/v) concentration was determined to be the most suitable matrix for these separations. This polymer, in coated capillaries, provided highly robust and reproducible separations, with near baseline resolution of fragments having single base differences. Reductions in the temperature of the separation, from 60 degrees C to 40 degrees C, and the urea concentration of the buffer, from 7 M to 3.5 M, provided increased longevity of the PEO polymer for repeated separations. Comparison of this polymer with currently specified commercial products used for STR analysis showed that the optimized PEO matrix provided superior separations under all conditions tested. In addition, PEO could be utilized in shorter capillary systems, with a concurrent decrease in analysis time, highlighting its potential for use in shortened capillary or microdevice systems. 相似文献
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