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961.
246 men and 191 women (aged 40–72 yrs) were monitored for medical care utilization in a health maintenance organization (HMO) over a 5-yr period. Rates of utilization were related to initially obtained indicators of life stress and social support and to interactions between life stress, social support, and age. Predictors of male and female HMO use are discussed. Multiple regression permitted a distinction between immediate and delayed effects of stresses on HMO visits. Implications regarding the buffering hypothesis for the mitigating effects of social support on the likelihood of health breakdown are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
962.
Energy-stability theory is applied to the case of radiation heat transfer in an optically thin, quiescent fluid layer heated from below and bounded by rigid, black, perfectly conducting planes. The radiation term in the energy equation destroys the quadratic character of the energy identity. It is shown, however, that the right-hand side of the energy identity can be bounded by a suitable quadratic term for all physically allowable disturbances. The result is a conditional stability limit dependent upon disturbance amplitude. Results are computed for a variety of cases; these are compared to existing linear and energy stability results.  相似文献   
963.
964.
The authors evaluated sexual practices, sexually tempting situations, and risk avoidance coping strategies among HIV-seropositive men who have sex with men and who were seeking HIV prevention services. HIV-seropositive men who practiced unprotected anal intercourse in the previous 4 weeks reported stronger temptations to engage in high-risk sex than men who were sexually safe. Being in a positive mood and being with desirable partners were particularly tempting risk situations for seropositive men, who also possessed less coping capacity to deal with risky situations than safer men. Prevention interventions must address the needs of men infected with HIV and must remove barriers to enrolling in prevention programs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
965.
Over the past 15 years, disorders of the self have occupied the attention of the psychoanalytic community. In particular, Otto Kernberg and Heinz Kohut have written extensively about narcissism, but from distinctly different theoretical vantage points. Each theorist has attracted adherents, but the debate between the conflict and deficit models of narcissism has been largely polemical, serving to further polarize the psychoanalytic community. Using the techniques of causal modeling, the article introduces this powerful data analytic strategy to psychoanalytic researchers and tests a model of narcissism which permits a direct, empirical comparison of some of the ideas of Kernberg and Kohut. In a number of strategic comparisons involving the theoretical underpinnings of narcissism--the structural stability of the self, damaged self-esteem, and grandiosity--these data appear to be more consistent with the deficit model, although various aspects of the conflict model also find support. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
966.
Covert channels are information leaks in systems that use resources to transfer secretly a message. They are a threat for security, performance, but also for a system's profitability. This paper proposes a new approach to detect covert channels from scenario models of protocols. The problem of finding covert channels in scenarios is first modeled as a game, in which a pair of malicious users S,R is trying to transfer information while the rest of the protocol tries to prevent it. The messages transferred are encoded by behavioral choices at some precise moments, and decoded by a transducer whose input vocabulary is an observation of the system. We then characterize the presence of a covert channel as the existence of a winning strategy for S,R and of a decoder.  相似文献   
967.
Supercritical Debinding of Injection Molded Ceramics   总被引:1,自引:0,他引:1  
Extraction of organic additives from extrusion-molded cylinders of alumina by a supercritical fluid is investigated. Hildebrand parameters alone are not adequate to predict conditions for optimal polymer extraction with supercritical CO2. The results obtained with two models developed for the kinetics of binder extraction suggest that polymer extraction from green samples is controlled by diffusion without development of a reaction front. The solubility and diffusivity of polymers both affect the extraction rate, with opposite pressure and temperature dependencies.  相似文献   
968.
969.
Reviews the book, Devenir consultant: instrument autogéré de formation (Module d'apprentissage I et Dossier d'intervention II by Robert Robert Lescarbeau, Maurice Rayette, and Yves St-Arnaud (1985). This book is a pedagogic tool intended to facilitate the consultation training. It is composed of two handbooks. The first, Modules of Training, constitute the basic text. The second, File of Intervention, are a collection of relevant instruments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
970.
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