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81.
82.
The current study used ecological momentary assessment to test several tenets of the reserve capacity model (L.C. Gallo & K. A. Matthews, 2003). Women (N = 108) with varying socioeconomic status (SES) monitored positive and negative psychosocial experiences and emotions across 2 days. Measures of intrapsychic and social resources were aggregated to represent the reserve capacity available to manage stress. Lower SES was associated with less perceived control and positive affect and more social strain. Control and strain contributed to the association between SES and positive affect. Lower SES elicited greater positive but not negative emotional reactivity to psychosocial experiences. Women with low SES had fewer resources relative to those with higher SES, and resources contributed to the association between SES and daily experiences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
83.
Viewing a distorted face induces large aftereffects in the appearance of an undistorted face. The authors examined the processes underlying this adaptation by comparing how selective the aftereffects are for different dimensions of the images including size, spatial frequency content, contrast, and color. Face aftereffects had weaker selectivity for changes in the size, contrast, or color of the images and stronger selectivity for changes in contrast polarity or spatial frequency. This pattern could arise if the adaptation is contingent on the perceived similarity of the stimuli as faces. Consistent with this, changing contrast polarity or spatial frequency had larger effects on the perceived identity of a face, and aftereffects were also selective for different individual faces. These results suggest that part of the sensitivity changes underlying the adaptation may arise at visual levels closely associated with the representation of faces. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
The state space explosion problem in model checking remains the chief obstacle to the practical verification of real-world distributed systems. We attempt to address this problem in the context of verifying concurrent (message-passing) C programs against safety specifications. More specifically, we present a fully automated compositional framework which combines two orthogonal abstraction techniques (operating respectively on data and events) within a counterexample-guided abstraction refinement (CEGAR) scheme. In this way, our algorithm incrementally increases the granularity of the abstractions until the specification is either established or refuted. Our explicit use of compositionality delays the onset of state space explosion for as long as possible. To our knowledge, this is the first compositional use of CEGAR in the context of model checking concurrent C programs. We describe our approach in detail, and report on some very encouraging preliminary experimental results obtained with our tool MAGIC.  相似文献   
85.
ROGUE is an architecture built on a real robot which provides algorithms for the integration of high-level planning, low-level robotic execution, and learning. ROGUE addresses successfully several of the challenges of a dynamic office gopher environment. This article presents the techniques for the integration of planning and execution.ROGUE uses and extends a classical planning algorithm to create plans for multiple interacting goals introduced by asynchronous user requests. ROGUE translates the planner';s actions to robot execution actions and monitors real world execution. ROGUE is currently implemented using the PRODIGY4.0 planner and the Xavier robot. This article describes how plans are created for multiple asynchronous goals, and how task priority and compatibility information are used to achieve appropriate efficient execution. We describe how ROGUE communicates with the planner and the robot to interleave planning with execution so that the planner can replan for failed actions, identify the actual outcome of an action with multiple possible outcomes, and take opportunities from changes in the environment.ROGUE represents a successful integration of a classical artificial intelligence planner with a real mobile robot.  相似文献   
86.
The authors examined the role of family factors and the course of schizophrenia by carrying out additional assessments and analyses in 2 previously published studies of Mexican American and Anglo American patients and families. The authors found partial support for an attributional model of relapse for families who are low in emotional overinvolvement. Attributions of control, criticism, and warmth together marginally predicted relapse. The data also indicated that for Mexican Americans, family warmth is a significant protective factor, whereas for Anglo Americans, family criticism is a significant risk factor. These findings suggest that the sociocultural context shapes the pathways by which family processes are related to the course of illness. Moreover, the warmth findings suggest that families may contribute to preventing relapse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
87.
88.
The current U.S. Environmental Protection Agency protocol for testing the effectiveness of dispersants, the swirling flask test, has been found to give widely varying results in the hands of different testing laboratories. The sources of the ambiguities in the test were determined by considering several options in a rigorous systematic fashion. Options considered were variability among three operators and the variability and limitations of three analytical instruments in establishing a calibration curve for oil/dispersant mixtures. Other options included flask type, impact of operational variables (rotational speed, mixing time, settling time, and oil:dispersant ratio), development of a revised procedure for dispersant effectiveness, reproducibility and repeatability of the revised procedure, and development of selection criteria for screening of dispersants. A redesign of the test flask, which is characterized by having baffles with a stopcock at the bottom for sample collection, was deemed necessary to accomplish reproducibility within operator and between operators. The results indicated that the baffled flask provided a total coefficient of variation (variations within operator and between operators) less than 11% compared to above 100% in some cases for the swirling flask.  相似文献   
89.
The current U.S. Environmental Protection Agency (EPA) protocol for testing the effectiveness of dispersants for use in treating oil spills on the open water, the swirling flask test (SFT), has been found to give widely varying results in the hands of different testing laboratories. Part I addressed the sources of the ambiguities in the EPA SFT and the development of a new test referred to as the baffled flask test (BFT). In this part of the series, further experiments were conducted for estimating the repeatability of three operators in determining the effectiveness of 18 dispersants by both the EPA SFT and the BFT methods. Overall statistical analysis of the results indicated that the coefficient of variation by the BFT was only 7.8% compared to 21.9% for the EPA SFT. The mean percent effectiveness of the EPA SFT was only 19.7% as compared to 64.6% for the BFT. Proposed selection criteria for screening of dispersants for listing on the National Contingency Plan Product Schedule have been developed.  相似文献   
90.
Eighty clients enrolled in a managed care health plan who identified panic disorder as their primary presenting problem were randomly assigned to treatment by a therapist recently trained in a manual-based empirically supported psychotherapy (M. G. Craske, E. Meadows, & D. H. Barlow, 1994) or a therapist conducting treatment as usual (TAU). Participants in both conditions showed significant change from pre- to posttreatment on a number of measures. Those receiving panic control therapy (PCT) showed greater levels of change than those receiving TAU. Among treatment completers, an average of 42.9% of those in PCT and 18.8% in TAU achieved clinically significant change across measures. The results are discussed with reference to the dissemination of PCT and other evidence-based psychotherapies to clinical practice settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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