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991.
Objective: The familial context plays an important role in psychosocial responses to genetic testing. The purpose of this study was to compare sibling pairs with different combinations of BRCA1/BRCA2 test results on measures of affect, interpersonal responses, and physiological reactions. Design: Forty-nine sibling dyads with different combinations of BRCA1/BRCA2 test results (i.e., mixed, positive, negative) completed a questionnaire, and 35 of the dyads also participated in a laboratory-based discussion of genetic testing. Main Outcome Measures: The primary outcome variables included participant reports of supportive actions toward their sibling, state anger and anxiety, perceptions of sibling behavior, and electrodermal responses. Results: Compared to positive and negative dyads, mixed pairs reported less friendly general support actions, noted more anger, and perceived their sibling to be less friendly and more dominant during the interactions. In comparisons between same-result (i.e., positive, negative) pairs, positive dyads reported more dominant support behaviors and perceived their sibling to be friendlier during the interactions. Conclusion: Data suggest that siblings who have different test results may experience more interpersonal strain than siblings who have the same test result. Future research on genetic testing and family relationships can expand upon these findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
School psychology at the doctoral level is recognized as a specialty of professional psychology by the American Psychological Association, with corresponding licensure as a psychologist granted by state boards of psychology. School psychology also is regulated by state boards of education; they set the credentialing standards for professional practice in public schools. The intent of this article is to enhance the understanding of this distinct and multiply influenced specialty. The need for psychological services in schools is highlighted, followed by a discussion of multiple influences and licensing/credentialing issues. Next, the specialty is delineated, its distinctiveness highlighted, and competencies for practice in the public schools elaborated. Finally, education/training models and mechanisms for program accreditation are described, as are the major professional organizations in school psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
993.
In 1988, the control of the American Psychological Association shifted to those advocating the interests of professional practice and a substantial segment of the scientific community in psychology seceded to form the American Psychological Society, devoted to scientific psychology and scientific-based practice. In this climate, it has become increasingly difficult for scientists and practitioners to maintain analytical discussions of the philosophical and methodological issues that divide these two groups. For over 25 years, the authors have been fortunate to have the professional and intellectual luxury of just such a discussion, and present here a dialogue that attempts to capture their initial stark differences in perspective and the process by which differences have been clarified, and areas of agreement established. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
994.
Mexican American students are the fastest growing group in U.S. public schools. There is a growing body of research indicating that Mexican American families underutilize mental health services and are more likely to drop out of care prematurely when they do seek help. These findings may indicate that our health care system is not providing ethnic minorities with culturally competent care. Although cognitive?behavioral interventions are considered to be evidence-based treatments for child anxiety disorders, previous protocols have not taken cultural factors into account. This article discusses how to adapt cognitive?behavioral therapy (CBT) for Mexican American students with anxiety disorders. Working within the Psychotherapy Adaptation and Modification Framework (PAMF), this article offers adaptation principles that may guide school psychologists in implementing CBT strategies when working with Mexican American youth and their families. A case study is provided illustrating how cultural modifications of CBT can lead to positive outcomes for Mexican American students. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
995.
Building on the network theory of brokerage and closure, this study takes a structural approach to examine network structure and its influence on reception of different types of social support. The study extracted ego networks of 227 active users from a large online health social network and tracked their received supportive comments on personal profiles for 3 months. A total of 3,270 comments were analyzed. The results showed that network brokerage (operationalized as effective size) predicted the amount of informational and network support, whereas network closure (operationalized as local clustering coefficient) predicted the amount of emotional and esteem support received on one's profile. Moreover, brokerage was found to predict received emotional support. Theoretical and practical implications were discussed.  相似文献   
996.
997.
A deployable, shape memory polymer adapter is investigated for reducing the hemodynamic stress caused by dialysis needle flow impingement within an arteriovenous graft. Computational fluid dynamics simulations of dialysis sessions with and without the adapter demonstrate that the adapter provides a significant decrease in the wall shear stress. Preliminary in vitro flow visualization measurements are made within a graft model following delivery and actuation of a prototype shape memory polymer adapter. Both the simulations and the qualitative flow visualization measurements demonstrate that the adapter reduces the severity of the dialysis needle flow impingement on the vascular access graft.  相似文献   
998.
Accurate predictions of image variances can be useful for reconstruction algorithm analysis and for the design of regularization methods. Computing the predicted variance at every pixel using matrix-based approximations [1] is impractical. Even most recently adopted methods that are based on local discrete Fourier approximations are impractical since they would require a forward and backprojection and two fast Fourier transform (FFT) calculations for every pixel, particularly for shift-variant systems like fan-beam tomography. This paper describes new "analytical" approaches to predicting the approximate variance maps of 2-D images that are reconstructed by penalized-likelihood estimation with quadratic regularization in fan-beam geometries. The simplest of the proposed analytical approaches requires computation equivalent to one backprojection and some summations, so it is computationally practical even for the data sizes in X-ray computed tomography (CT). Simulation results show that it gives accurate predictions of the variance maps. The parallel-beam geometry is a simple special case of the fan-beam analysis. The analysis is also applicable to 2-D positron emission tomography (PET).  相似文献   
999.
In clinical applications where structural asymmetries between homologous shapes have been correlated with pathology, the questions of definition and quantification of "asymmetry" arise naturally. When not only the degree but the position of deformity is thought relevant, asymmetry localization must also be addressed. Asymmetries between paired shapes have already been formulated in terms of (nonrigid) diffeomorphisms between the shapes. For the infinity of such maps possible for a given pair, we define optimality as the minimization of deviation from isometry under the constraint of piecewise deformation homogeneity. We propose a novel variational formulation for segmenting asymmetric regions from surface pairs based on the minimization of a functional of both the deformation map and the segmentation boundary, which defines the regions within which the homogeneity constraint is to be enforced. The functional minimization is achieved via a quasi-simultaneous evolution of the map and the segmenting curve, conducted on and between two-dimensional surface parametric domains. We present examples using both synthetic data and pairs of left and right hippocampal structures and demonstrate the relevance of the extracted features through a clinical epilepsy classification analysis.  相似文献   
1000.
This paper demonstrates a chemical surface modification method for covalent attachment of various polymers by using silane-based "click" chemistry on silica surfaces and within glass microchannels suitable for CE systems. Modified surfaces are characterized by contact angle measurements, X-ray photoelectron spectroscopy, and Fourier transform infrared-attenuated total reflection spectroscopy. Electroosmotic flow (EOF) measurements in modified and unmodified channels are provided. Spectroscopic and transport data show that various polymers can be covalently attached to glass surfaces with a measurable change in EOF.  相似文献   
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