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841.
Relationships between perceived life satisfaction and sexual risk-taking behaviors were examined in a statewide sample of public high school students (n = 4,758) using the self-report CDC Youth Risk Behavior Survey (YRBS). Adjusted polychotomous logistic regression analyses and multivariate models (via SUDAAN) constructed separately, revealed a significant race by gender interaction for each race-gender group. Age of first intercourse (13), two or more lifetime sexual intercourse partners, alcohol/drug use before last intercourse, no use of contraception at last intercourse, being forced to have sex, forcing someone to have sex, and having beaten up a date in the last 12 months and having been beaten up by a date (in last 12 months) were associated (p = .05) with reduced life satisfaction. Measures of life satisfaction as a component of comprehensive assessments of adolescent sexual risk-taking behaviors in fieldwork, research, and program-evaluation efforts should be considered.  相似文献   
842.
843.
When a meta-analysis on results from experimental studies is conducted, differences in the study design must be taken into consideration. A method for combining results across independent-groups and repeated measures designs is described, and the conditions under which such an analysis is appropriate are discussed. Combining results across designs requires that (a) all effect sizes be transformed into a common metric, (b) effect sizes from each design estimate the same treatment effect, and (c) meta-analysis procedures use design-specific estimates of sampling variance to reflect the precision of the effect size estimates.  相似文献   
844.
The processing of emotional expressions is fundamental for normal socialization and interaction. Reduced responsiveness to the expressions of sadness and fear has been implicated in the development of psychopathy (R. J. R. Blair, 1995). The current study investigates the ability of adult psychopathic individuals to process vocal affect. Psychopathic and nonpsychopathic adults, defined by the Hare Psychopathy Checklist-Revised (PCL-R; R. D. Hare, 1991), were presented with neutral words spoken with intonations conveying happiness, disgust, anger, sadness, and fear and were asked to identify the emotion of the speaker on the basis of prosody. The results indicated that psychopathic inmates were particularly impaired in the recognition of fearful vocal affect. These results are interpreted with reference to the low-fear and violence inhibition mechanism models of psychopathy.  相似文献   
845.
This article develops the argument that Friedrich Nietzsche influenced several aspects of Freud's later writings by illustrating, in particular, the impact of Nietzsche's On the Genealogy of Morals on Freud's Civilization and its Discontents. The theoretical and conceptual schemes represented in Freud's Discontents are found to bear a remarkable similarity to Nietzsche's Genealogy on a number of highly specific points. It is suggested that "DAS ES," "Uber-ich," and "bad conscience," concepts central to Freud's moral theory of mind, are at least partly derived from Nietzsche. Moreover, Freud's phylogenetic theory of guilt is based upon premises found in Nietzsche, as are specific details relating to ideas on human prehistory and the ancestral family. Based on this evidence, a re-examination of the moral and social dimensions of Freud's "structural" model may be in order.  相似文献   
846.

Dedication

Acknowledgments 2002  相似文献   
847.
This study examined how specific features of adaptive tests are related to test takers' reactions. Participants took a computer-adaptive test in which 2 features, difficulty of the initial item and difficulty of subsequent items, were manipulated, then responded to questionnaires assessing their reactions to the test. The data show that the relationship between a test's objective difficulty, which was determined by the 2 manipulated test characteristics, and reactions was fully mediated by perceived performance. Additional analyses evaluated the impact of feedback on reactions to the adaptive test. In general, feedback that was consistent with perceptions of performance was positively related to reactions. The results suggest that minor changes to the design of an adaptive test may potentially enhance examinees' reactions.  相似文献   
848.
Smell identification deficits are consistently found in schizophrenia (SZ), but little is known about the nature and characterization of this deficit or its relationship to the phenomenology of the illness. This study aims to further delineate smell identification errors in SZ by examining the relationship of patient demographic differences with smell-identification performance. Our results showed that a patient's gender and education were related to odor-identification scores, with better performance seen in female patients and in those with greater educational attainment. However, there was no effect related to age, ethnicity, or socioeconomic status on odor identification. A smell identification deficit was also unrelated to clinical characteristics of the patients, including age at first hospitalization, number of psychiatric hospitalizations, and duration of illness. Odor identification also did not differ by SZ subtype, nor between SZ and schizoaffective disorder patients. These findings emphasize that odor identification deficits in SZ are unrelated to clinical illness features, cannot be explained by other confounds related to olfaction in the general population, and may be core features related to the SZ disease process.  相似文献   
849.
Four rats obtained food pellets by poking a key and 5-s presentations of the discriminative stimuli by pressing a lever. Every 1 or 2 min, the prevailing schedule of reinforcement for key poking alternated between rich (either variable-interval [VI] 30 s or VI 60 s) and lean (either VI 240 s, VI 480 s, or extinction) components. While the key was dark (mixed-schedule stimulus), no exteroceptive stimulus indicated the prevailing schedule. A lever press (i.e., an observing response), however, illuminated the key for 5 s with either a steady light (S+), signaling the rich reinforcement schedule, or a blinking light (S-), signaling the lean reinforcement schedule. One goal was to determine whether rats would engage in selective observing (i.e., a pattern of responding that maintains contact with S+ and decreases contact with S-). Such a pattern was found, in that a 5-s presentation of S+ was followed relatively quickly by another observing response (which likely produced another 5-s period of S+), whereas exposure to S- resulted in extended breaks from observing. Additional conditions demonstrated that the rate of observing remained high when lever presses were effective only when the rich reinforcement schedule was in effect (S+ only condition), but decreased to a low level when lever presses were effective only during the lean reinforcement component (S- only condition) or when lever presses had no effect (in removing the mixed stimulus or presenting the multiple-schedule stimuli). These findings are consistent with relativistic conceptualizations of conditioned reinforcement and extend the generality of selective observing to procedures in which the experimenter controls the duration of stimulus presentations, the schedule components both offer intermittent food reinforcement, and rats serve as subjects.  相似文献   
850.
Rats obtained food pellets by nose poking a lighted key, the illumination of which alternated every 50 s during a session between blinking and steady, signaling either a relatively rich (60 per hour) or relatively lean (15 per hour) rate of reinforcement. During one training condition, all the reinforcers in the presence of the rich-reinforcement signal were response dependent (i.e., a variable-interval schedule); during another condition only 25% were response dependent (i.e., a variable-time schedule operated concurrently with a variable-interval schedule). An extinction session followed each training block. For both kinds of training schedule, and consistent with prior results, response rate was more resistant to extinction in the presence of the rich-reinforcement signal than in the presence of the lean-reinforcement signal. Analysis of interresponse-time distributions from baseline showed that differential resistance to extinction was not related to baseline differences in the rate of initiating response bouts or in the length of bouts. Also, bout-initiation rate (like response rate) was most resistant to extinction in the presence of the rich-reinforcement signal. These results support the proposal of behavioral momentum theory (e.g., Nevin & Grace, 2000) that resistance to extinction in the presence of a discriminative stimulus is determined more by the stimulus-reinforcer (Pavlovian) than by the stimulus-response-reinforcer (operant) contingency.  相似文献   
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