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931.
932.
Recent legislative and regulatory developments have focused attention on older adults' capacity for involvement in health care decision-making. The Omnibus Budget Reconciliation Act of 1987 (OBRA 87) focused attention on the rights of nursing home residents to be involved in health care decision-making to the fullest extent possible. This article uses data from the 1987 National Medical Expenditure Survey (NMES) to examine rates of incapacity for health care decision-making among nursing home residents. Elements of the Oklahoma statute were used to operationalize decision-making incapacity: disability or disorder, difficulty in decision-making or communicating decisions, and functional disability. Fifty-three percent of nursing home residents had a combination of either physical or mental impairment and an impairment in either self-care or money management. The discussion focuses on the policy and practice implications of significant rates of incapacity among nursing home residents.  相似文献   
933.
Four pigeons responded on multiple schedules arranged on a “main” key in a two-key experimental chamber. A constant schedule component was alternated with another component that was varied over conditions. On an extra response key, conjoint schedules of reinforcement that operated in both components were arranged concurrently with the multiple schedule on the main key. On the main key, changes in reinforcement rate in the varied component were inversely related to changes in response rates in the constant component (behavioral contrast). On the extra key, some reinforcers were reallocated between components, depending on the schedules in effect on the main key in the varied component. In the varied component, the obtained rates of reinforcement on the extra key were inversely related to main-key reinforcement rate. In the constant component, extra-key reinforcer rates were positively related to main-key reinforcer rates obtained in the varied component, and were not a function of response rates on the extra key. In two comparisons, the rate at which components alternated and the value of the main-key schedule in the constant component were varied. Consistent with earlier work, long components reduced the extent of contrast. Reductions in contrast as a function of component duration were accompanied by similar reductions in the extent of reinforcer reallocation on the extra key. In the second comparison, lowering the rate of reinforcement in the constant component increased the rate at which extra-key reinforcers were obtained, reduced the extent of reinforcer reallocation, and reduced contrast. Overall, the results are consistent with the suggestion that some contrast effects are due to the changes in extraneous reinforcement during the constant component, and that manipulations of component duration, and manipulations of the rate of reinforcement in the constant component, affect contrast because they influence the extent of extraneous reinforcer real-location.  相似文献   
934.
Behavioral momentum theory relates resistance to change of responding in a multiple-schedule component to the total reinforcement obtained in that component, regardless of how the reinforcers are produced. Four pigeons responded in a series of multiple-schedule conditions in which a variable-interval 40-s schedule arranged reinforcers for pecking in one component and a variable-interval 360-s schedule arranged them in the other. In addition, responses on a second key were reinforced according to variable-interval schedules that were equal in the two components. In different parts of the experiment, responding was disrupted by changing the rate of reinforcement on the second key or by delivering response-independent food during a blackout separating the two components. Consistent with momentum theory, responding on the first key in Part 1 changed more in the component with the lower reinforcement total when it was disrupted by changes in the rate of reinforcement on the second key. However, responding on the second key changed more in the component with the higher reinforcement total. In Parts 2 and 3, responding was disrupted with free food presented during intercomponent blackouts, with extinction (Part 2) or variable-interval 80-s reinforcement (Part 3) arranged on the second key. Here, resistance to change was greater for the component with greater overall reinforcement. Failures of momentum theory to predict short-term differences in resistance to change occurred with disruptors that caused greater change between steady states for the richer component. Consistency of effects across disruptors may yet be found if short-term effects of disruptors are assessed relative to the extent of change observed after prolonged exposure.  相似文献   
935.
What Do We Know When We Know a Person?   总被引:12,自引:1,他引:11  
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936.
This study investigated the relationship between coping strategies and distress symptomatology in survivors of sexual revictimization. Coping strategies were assessed with the revised Ways of Coping Scale (Aldwin & Revenson, 1987). Distress symptoms included global distress, depression, anxiety, and somatization. Subjects were 44 survivors of sexual victimization in both childhood and adulthood; 54 survivors of a single incident of sexual victimization in childhood; and 256 nonvictimized individuals. All were drawn from a subject pool of female undergraduate students. Multivariate analysis of variance revealed significant differences between groups on reported symptomatology and coping strategies. Victimized groups reported more distress than did the nonvictimized group. The multiple victimization group indicated greater use of coping strategies than did the nonvictimized group, and both victimized groups reported greater use of the escapism strategy than did the nonvictimized group. Multiple backward regression analysis found that coping strategies were predictive of distress symptomatology in all three groups, with escapism as the most potent predictor of distress for each group. Coping strategies were the most powerful predictors of distress in the multiply victimized group. The results of this study provide strong support for the importance of addressing coping strategies in clinical intervention of distress, particularly with survivors of multiple sexual victimization.  相似文献   
937.
The control of the ground reaction force vector relative to the center of gravity (CoG) was examined while subjects performed a back-lifting task. Six male subjects (aged 24.0 +/- 2.5 years) repeatedly lifted a barbell. A biomechanical analysis that used a linked segment model revealed that the summed rotations of body segments during lifting yielded a specific rate of change of the angular momentum of the entire body. This equaled the external moment provided by Fsubg; relative to CoG. This implies that multisegment movements involve control of the angular momentum of the entire body through an appropriately directed Fsubg;. Thus, in dynamic tasks Fsubg; is pointed away from rather than lined up with the CoG, as is the case in static tasks.  相似文献   
938.
Based on extensive formative research in the three Eastern Caribbean countries of St. Lucia, St. Vincent and the Grenadines, and Grenada (Fishbein, Middlestadt, & Trafimow, 1993; Fishbein, Trafimow, et al., 1993), a three-nation, mass media, condom use campaign was developed. In order to assess the impact of the campaign, a follow-up survey was conducted in St. Vincent and the Grenadines. This paper examines the effectiveness of the campaign by comparing responses on this survey by respondents who were or were not exposed to the campaign. A statistically significant impact of exposure to the campaign was obtained, indicating that a well-designed, empirically based, mass media campaign can be an effective tool in the battle to prevent the spread of AIDS.  相似文献   
939.
Conclusion I have tried to demonstrate that black church defiant spirituality is a complex, multi-dimensional phenomenon. In essence it represents the quest of exiled African peoples to experience ontological harmony with God and all of creation. In the context of a racist society, it has adapted itself to the exigencies of survival and gradual liberation. Specifically, it has sought to reconstruct reality by religiously affirming God's sovereignty over the just and unjust. Also, it has negated black invisibility, subverted political anemia, and now struggles to resist and conquer an encroaching spiritual despair in post-industrial society.I have identified three basic treasures which the black church may offer to other cultures, namely, that care and discipline are the responsibility of every Christian, that authentic Christian worship nurtures commitments to individual and social transformation and it offers a full sensory experience. I close with words from one of America's greatest twentieth century poets, Langston Hughes (1974)—entitled Mother to Son: Well, son, I'll tell you: Life for me ain't been no crystal stair. It's had tacks in it, And splinters, And boards torn up, And places with no carpet on the floor—Bare. But all the time I'se been a-climbin' on, And reachra' landin's, And turnin' corners, And sometimes goin' in the dark Where there ain't been no light. So boy, don't you turn back. Don't you set down on the steps 'Cause you finds it's kinder hard. Don't you fall now —For I'se still goin', honey, I'se still climbin', And life for me ain't been no crystal stair. (p. 187)  相似文献   
940.
A problem which enthusiasts ofIST, Nelson's internal set theory, usually face is how to treat external sets in the internal universe which does not contain them directly. To solve this problem, we considerBST,bounded set theory, a modification ofIST which is, briefly, a theory for the family of thoseIST sets which are members of standard sets.We show thatBST is strong enough to incorporate external sets in the internal universe in a way sufficient to develop the most advanced applications of nonstandard methods. In particular, we define inBST an enlargement of theBST universe which satisfies the axioms ofHST, an external theory close to a theory introduced by Hrbaek. HST includes Replacement and Saturation for all formulas but contradicts the Power Set and Choice axioms (either of them is incompatible with Replacement plus Saturation), therefore to get an external universe which satisfies all ofZFC minus Regularity one has to pay by a restriction of Saturation. We prove thatHST admits a system of subuniverses which modelZFC (minus Regularity but with Power Set and Choice) and Saturation in a form restricted by a fixed but arbitrary standard cardinal.Thus the proposed system of set theoretic foundations for nonstandard mathematics, based on the simple and natural axioms of the internal theoryBST, provides the treatment of external sets sufficient to carry out elaborate external constructions.Partially supported by AMS grants in 1993 and 1994 and DFG grant in 1994.Presented byRobert Goldblatt  相似文献   
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