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921.
The purpose of the paper is to present a logical framework that allow to formalize a kind of prima facie duties, defeasible conditional duties, indefeasible conditional duties and actual (indefeasible) duties, as well as to show their logical interconnections.  相似文献   
922.
923.
We present three experiments designed to investigate the role of prosody during sentence processing. The first investigated the question of whether an utterance's prosodic contour influences its comprehension on-line. We spliced the beginning and end portions of direct object and embedded clause sentences and observed the consequent effects on comprehension using a dual-task procedure to measure processing load. Our second experiment sought to determine-whether the constituent structure of these sentences could be reliably predicted using prosodic information. We found that the duration and F0 contour associated with the main-clause verb and the following NP reliably distinguished between the direct object and embedded clause constructions. In the final experiment, we manipulated the duration of the main-clause verb and found that subjects used this information to guide their initial parse during on-line sentence comprehension. The need for a model of sentence processing that addresses the use of prosodic information is discussed.The work reported in this paper was supported in part by NTH grant DC00494.  相似文献   
924.
The importance of using culturally sensitive educational materials in HIV-related interventions with racial and ethnic minority groups is widely recognized. However, little empirical research has been conducted to assess the relative effectiveness of different techniques for creating culturally sensitive AIDS educational videos. Two field experiments with three samples of African American adults (N = 174, 173, and 143) were conducted to assess how source characteristics (race of communicator), message characteristics (multicultural message vs. culturally specific message), and audience characteristics (racial distrust and AIDS-related distrust) influence proximate (perceptions of the message's credibility and attractiveness) and distal (AIDS-related attitudes, beliefs, and behavioral intentions) output variables for AIDS educational videos. In Study 1, an AIDS video with a culturally specific message was rated as more credible, more attractive, and of higher quality than was a video with a multicultural message. The multicultural message was rated less favorably when delivered by a White announcer than when the announcer was Black. In Study 2, the same pattern was replicated with a second community sample and a campus-based sample. Study 2 also indicated that a multicultural message might be more effective if delivered in a culturally specific context, namely, after audience members watch a culturally specific video. Minimal changes were observed in distal outcome variables. It is argued that influencing proximate output variables is necessary, though not sufficient, for effecting long-term change in AIDS-related attitudes, beliefs, and behaviors.  相似文献   
925.
Although few guidelines exist, many therapists use prayer as a part of psychotherapy. The immense variance inherent in prayer behaviors and the paucity of literature on its use beckons the profession to develop a model for its use in therapy, examine the ethical implications for such use, and prepare guidelines for practice. A tripartite model for the conceptualization and localization of prayer in therapy is presented, ethical issues of therapist bias and competence and clients' right to autonomous decision making are considered, and guidelines for employing prayer in psychotherapy are developed.  相似文献   
926.
Recent research on hunger and eating has shown that (a) among individuals with adlibitum access to food, hunger and eating are not regulated by deviations in the body's energy resources from set-points, and (b) it is healthier for people to consume their daily caloric intake as several small snacks than as 3 large meals. People's beliefs about hunger and eating were assessed in 2 questionnaire studies. In Study 1, a large sample of undergraduates was surveyed; in Study 2, dietetics students, nursing students, medical students, dietitians, nurses, and doctors were surveyed. Both studies revealed that people's personal theories of hunger and eating were inconsistent with research findings in ways that could promote overconsumption. These results suggest that educational programs designed to modify the beliefs about hunger and eating of people suffering from problems of overconsumption and of health professionals who treat problems of overconsumption may increase the effectiveness of current treatment regimens.  相似文献   
927.
The proposal of Friman, Hayes, and Wilson (1998) that the concept of emotion be incorporated into behavior analysis is questioned. Their proposal is undermined by the problem of the verification of private events by others. A focus on private events, as exemplified by the proposal of Friman et al., can lead to a reversion to notions of agency and the autonomous individual. Also, the anchoring of hypothetical constructs to the behavioral data language is ill advised.  相似文献   
928.
Multiple baseline designs were used to examine the effects of an instructional package on accuracy of performance in solving multiplication facts by 3 students with learning disabilities. The instructional package included the following components: (a) a modified instructional sequence in which multiplication facts were grouped into the zeros, ones, doubles, fives, and nines categories, and those remaining; (b) identification of the category in which each fact belonged; (c) mnemonic strategies associated with solving facts in each category; and (d) steps to be completed for solving facts in each category. Results indicated that the instructional package produced substantial and immediate effects. After receiving instruction, a participant's accuracy was often 100%, and this was maintained throughout the evaluation even as other strategies were introduced. Comparable results occurred across students, demonstrating replication of the effects of the instructional package.  相似文献   
929.
FEMALE PARTNERS OF BISEXUAL MEN What They Don't Know Might Hurt Them   总被引:2,自引:0,他引:2  
Individual interviews with 350 behaviorally bisexual men aged 18–30 revealed that 71% of their female sexual partners and 59% of their steady female sexual partners in the past 6 months had not been aware of their homosexual activity. Rates of nondisclosure were higher for African-American than White men. Compared to nondisclosers, men who disclosed to all their female partners were less self-homophobic and perceived their friends, families, and neighbors as more accepting of their homosexual behavior. Compared to men who had disclosed, the nondisclosers had more female partners and used condoms less consistently with women.  相似文献   
930.
The purpose of the study is to investigate the influence of initial projection of the centre of gravity (CG) on the spatial and temporal organization of the dynamic phenomena accompanying a voluntary movement in humans. From a horizontal quadrupedal stance, ten normal subjects were instructed to raise the right forelimb towards a support target in self paced velocity conditions. Three experimental conditions were tested for which the initial CG projection was either within (C1), at the limits of (C2) or outside the supporting triangle (C3). The results showed that vertical force variations on the four supports always preceded the first vertical displacement of the right wrist (onset of the movement). From C1 to C3, the duration of these anticipatory dynamic phenomena increased enabling an adjustment of the CG position such that equilibrium constraints were fulfilled. For all conditions, the acceleration peak of the CG occurred prior to the onset of movement and from C1 to C3, its magnitude increased in a single direction of the horizontal plane. For each condition, the load transfer was directed to the left forelimb and the right hindlimb (diagonal strategy) and reached a maximal value at the time of lift-off. With respect to this moment, the onset of the movement occurred increasingly early from C1 to C3. These results suggest that contribution of peripheral cues to postural control is more important, when the requirements of horizontal CG displacement increase.  相似文献   
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