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801.
Contrast analysis of repeated-measures data generally focuses on hypotheses when only 1 pattern of results is of theoretical interest. This article articulates a framework for contrast analysis in repeated-measures contexts in which researchers have hypotheses relevant to 1 potential pattern or multiple potential patterns of results. For example, a researcher might ask whether participants exhibit a pattern of (a) immediate symptom reduction or (b) delayed symptom reduction. Alternatively, the researcher might ask whether 2 or more groups exhibit 2 or more patterns to differing degrees. Building on the familiar logic and computational procedures for 1-pattern hypotheses, the authors present a contrast analysis framework that integrates analysis of 1-pattern and multiple-pattern hypotheses and accommodates 1 group or multiple groups of participants. 相似文献
802.
Serotonin (5-HT) modulates numerous processes in the central nervous system that are relevant to neuropsychiatric function and dysfunction. It exerts significant effects on anxiety, mood, impulsivity, sleep, ingestive behavior, reward systems, and psychosis. Serotonergic dysfunction has been implicated in several psychiatric conditions but efforts to more clearly understand the mechanisms of this influence have been hampered by the complexity of this system at the receptor level. There are at least 14 distinct receptors that mediate the effects of 5-HT as well as several enzymes that control its synthesis and metabolism. Pharmacologic agents that target specific receptors have provided clues regarding the function of these receptors in the human brain. 5-HT is also an important modulator of neural development and several groups have employed a genetic strategy relevant to behavior. Several inactivation mutations of specific 5-HT receptors have been generated producing interesting behavioral phenotypes related to anxiety, depression, drug abuse, psychosis, and cognition. In many cases, knockout mice have been used to confirm what has already been suspected based on pharmacologic studies. In other instances, mutations have demonstrated new functions of serotonergic genes in development and behavior. 相似文献
803.
The purpose of this article is to propose a simple effect size estimate (obtained from the sample size, N, and a p value) that can be used (a) in meta-analytic research where only sample sizes and p values have been reported by the original investigator, (b) where no generally accepted effect size estimate exists, or (c) where directly computed effect size estimates are likely to be misleading. This effect size estimate is called r(equivalent) because it equals the sample point-biserial correlation between the treatment indicator and an exactly normally distributed outcome in a two-treatment experiment with N/2 units in each group and the obtained p value. As part of placing r(equivalent) into a broader context, the authors also address limitations of r(equivalent). 相似文献
804.
Folkman and Lazarus's theory of stress and coping was used to develop a measure assessing the perceived stress within a bicultural context. Middle school students of Mexican descent (N = 881) reported their perceived stress from intergenerational acculturation gaps, within-group discrimination, out-group discrimination, and monolingual stress. Although immigrant youths reported more total number of stressors, U.S.-born youths reported more stress from needing better Spanish and impact of parents' culture. Immigrant youths reported more stress from needing better English in school. Higher stress was associated with more depressive symptoms for both U.S.-born and immigrant youths. Although this study has identified some elements of stress, it has not identified positive coping mechanisms of the bicultural context for Latino youths. 相似文献
805.
Tsai JL Pole N Levenson RW Muñoz RF 《Cultural diversity & ethnic minority psychology》2003,9(1):49-63
Emotional responses (physiology, self-report, and facial expression) of 12 depressed and 10 nondepressed Spanish-speaking Latinas during sad and amusing film clips of human and animal content were compared. Depressed Latinas demonstrated less electrodermal reactivity across all the film clips and displayed fewer social smiles during the amusing-human film clip than nondepressed Latinas. No differences emerged for cardiovascular measures, reports of emotion, or facial expressions of happiness and negative emotion. Observed differences in electrodermal reactivity are similar to results from previous studies of Anglo Americans, suggesting that reduced electrodermal activity may be linked to depression across cultures. The findings also suggest that, for Latinas, depression may selectively alter expressions that serve interpersonal functions. 相似文献
806.
McGinn RE 《Science and engineering ethics》2003,9(4):517-542
A survey on ethical issues in engineering was administered over a five-year period to Stanford engineering students and practicing
engineers. Analysis of its results strongly suggests that important disconnects exist between the education of engineering
students regarding ethical issues in engineering on the one hand, and the realities of contemporary engineering practice on
the other. Two noteworthy consequences of these gaps are that the views of engineering students differ substantially over
what makes an issue an ethical issue, while practicing engineers exhibit significant disagreement over what is the most important
non-technical aspect of being a responsible engineering professional in contemporary society. These divergences impede the
recognition of ethical issues and of specific moral responsibilities of engineers in concrete professional practice. It is
argued that the use of suitably refined and probing surveys of engineering students and practicing engineers about ethical
issues in engineering is an important although neglected empirical approach to the study of engineering ethics. Such an approach
can enhance the prevailing case study method and combat over-tidy theoretical-analytical approaches to the subject.
When a train arrives at a station in the London Underground, a public announcement cautions passengers to “mind the gap”,
i.e. heed the space between the station platform and the carriage while entering or exiting.
An early draft of this paper was presented at the International Conference on Ethics in Engineering and Computer Science,
Case Western Reserve University, Cleveland, Ohio, March 21–23, 1999. 相似文献
807.
Miller PN Lawrence RJ Powell RC 《The journal of pastoral care & counseling : JPCC》2003,57(2):111-116
In the current cultural context, clinically trained ministers, lay and ordained, offer themselves to troubled souls through at least three distinct varieties of assistance: pastoral care, pastoral counseling, and pastoral psychotherapy. This essay delineates three accepted disciplines, emphasizing the importance of ascertaining, and perhaps re-evaluating, the particular needs and desires of persons who are in physical, mental, or spiritual distress. "Pastoral care," "pastoral counseling," and "pastoral psychotherapy" each play an important role in fulfilling the traditional mandate for "the cure of souls." 相似文献
808.
The increasing use of verbal reports in psychological research requires tools for improving the ease and reliability of collecting
and coding verbal report data. An approach is described that maintains the verbal report data in digitally recorded audio
form throughout the collecting and encoding processes. A new computer-aided encoding tool, CAPAS, is described, which randomly
selects and plays individual protocol segments and stores computer keyboard-entered codes in an SPSS-formatted data file. 相似文献
809.
Devan BD Goad EH Petri HL Antoniadis EA Hong NS Ko CH Leblanc L Lebovic SS Lo Q Ralph MR McDonald RJ 《Neurobiology of learning and memory》2001,75(1):51-62
It is thought that circadian rhythms may influence learning and memory processes. However, research supporting this view does not dissociate a mnemonic impairment from other performance deficits. Furthermore, published reports do not specify the type of memory system influenced by the circadian system. The present study assessed the effects of phase shifting on acquisition and expression of place navigation in the water maze, a task sensitive to hippocampal dysfunction. The results showed that phase-shifting circadian rhythms in rats impaired the expression of place information on a retention test but not initial acquisition or encoding of place information. These results suggest that disruption of circadian rhythms may impair consolidation of previously encoded hippocampal place information. 相似文献
810.
Experiments were conducted in which observers learned to classify simple perceptual stimuli into low-variability and high-variability categories. Similarities between objects were measured in independent psychological-scaling tasks. The results showed that observers classified transfer stimuli into the high-variability categories with greater probability than was predicted by a baseline version of an exemplar-similarity model. Qualitative evidence for the role of category variability on perceptual classification, which could not be explained in terms of the baseline exemplar-similarity model, was obtained as well. Possible accounts of the effects of category variability are considered in the General Discussion section. 相似文献