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1.
Twenty-six suicide attempters, 9 to 18 years of age, were compared with 725 nonattempters on measures of school achievement, educational goals, socioeconomic status, and depression. As has been found in studies using clinical samples, suicide attempters in our communitybased sample had significantly lower school achievement than nonattempters. The relationship between attempted suicide and low school achievement seemed to be explained by the effects of depression. Lower-SES youth tended to be more likely to attempt suicide than higher-SES youths. However, SES appeared to have little effect on the relationship between attempted suicide and school achievement. Results also suggest that children of mothers with low educational goals for them may be more at risk for attempted suicide than youths whose mothers have higher educational goals for their children.This research was supported by the National Institute of Mental Health, Grant No. MH36971.  相似文献   
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Developed empowerment theory and replicated previous research on citizen participation and perceived control. Few investigators have designed studies that specifically test empowerment theory. This research further extends a theoretical model of psychological empowerment that includes intrapersonal, interactional, and behavioral components, by studying a large randomly selected urban and suburban community sample and examining race differences. Results suggest that one underlying dimension that combines different measures of perceived control may be interpreted as the intrapersonal component of psychological empowerment, because it distinguishes groups defined by their level of participation in community organizations and activities (behavioral component). The association found between the intrapersonal and behavioral components is consistent with empowerment theory. Interaction effects between race groups and participation suggest that participation may be more strongly associated with the intrapersonal component of psychological empowerment for African Americans than for white individuals. Implications for empowerment theory and intervention design are discussed. The authors express appreciation to Steven Rosenstone who was the Principal Investigator for the Detroit Area Study from which the data for our study is based. We also thank Deborah A. Salem and the anonymous reviewers for their thoughtful comments on earlier drafts of this paper.  相似文献   
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The use of neurological tests in various states of undernutrition has confirmed the presence of delays in reflex ontogeny. Glucocorticoid administration in conditions of normal nutrition produces diminished growth and alterations in brain development similar to those observed in malnutrition, but there is not enough evidence about its effect on reflex development. In addition, some facts lead us to think that the use of permissive doses of these hormones during gestation could alleviate some of the effects of protein malnutrition on the development of pups. In the present study the ages at which certain reflexes appeared in the offspring of Wistar rats (Rattus norvegicus) fed a 20% (N) or 10% (M) protein diet from a week before conception to the end of lactation were observed. Each dietary group was subdivided into two: mothers receiving a daily injection during gestation either of a 0.9% NaCl (S) solution or of a 0.5 mg/100 g weight hydrocortisone acetate (C) solution. Results showed that the NS group of pups generally presented earlier ages of appearance of the variables under study than the remaining groups. Pups of the NC group presented delays in the age of appearance of reflexes. Finally, protein malnutrition delayed the appearance of reflexes and this effect seemed to be attenuated by treatment with hydrocortisone. Thus, hydrocortisone administration in protein malnutrition conditions seems to be beneficial although the results are harmful when administered under normal nutritional conditions.  相似文献   
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A rapid serial visual presentation (RSVP) paradigm using both one and two response dimensions was used to test parallel processing models of stimulus dimensions. Fifty subjects were asked to report the identity and/or color of a target uppercase word inserted in a series of lowercase words. The results produced a predominance of posttarget intrusions for color responses and a predominance of pretarget intrusions for identity responses. The requirement of a response to a second dimension impaired hit rates but did not change the pattern of intrusions. An examination of the distributions of intrusions in each response dimension as a function of the response given to the other dimension showed an unexpectedly high percentage of simultaneous hits, a moderate covariation between both responses, and the same patterns of intrusions when compared with the general distributions. While these results seem to be compatible with parallel models of processing for stimulus dimensions, two modifications to this model are suggested. First, the processing of response dimension(s) needs some attentional resources. Second, provision for a mixed model is indicated, which would include trials where no illusory conjunctions are formed.  相似文献   
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Guideline sentencing systems, including the new federal guidelines, have not settled on a clear conception of when and how a trial judge should explain sentences. Indeterminate sentencing systems did not have a tradition of written sentencing decisions and recent sentencing reforms do not focus on the trial judge's role. This article suggests the many advantages of written sentencing opinions. Initial experience under the federal sentencing guidelines bolsters the conclusion that written sentencing opinions in appropriate cases—including both sentences “within” guidelines and guideline “departures”—are the next step in the evolving law of sentencing and the best way to recognize trial judges as an essential engine of principled change.  相似文献   
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Summary Four experiments were conducted to examine processes in identification and selective adaptation of hues in color perception that exactly parallel processes in identification and adaptation of auditory detectors that provide information for phonemic perception. The first experiment demonstrated an effect of adaptation on identification of blue and green when a hue category center was used as the adaptor; this experiment also assessed recovery from adaptation. Adaptation to one hue was found to shift identification to favor the alternative hue, implicating a single detector underlying hue categorization. The second experiment demonstrated similar effects of adaptation between green and yellow. The third experiment compared the magnitudes of shift following adaptation with a category center, a near-boundary hue, and variously graded adaptation series. Adaptation was found to be related to the category representativeness of the adaptor(s). Results of the third experiment also provided support for the view that adaptation, rather than response bias, is responsible for shifts in the position of identification functions following extended stimulus exposure. The fourth experiment explored the neural loci of adaptation by an interocular transfer test. Hue adaptation was found to occur at both central and peripheral loci. In the four main experiments, reaction times to identify hues in unadapted and adapted states were also analyzed and compared. Subsidiary experiments assessed the effects of stimulus luminance on the magnitude of adaptation. General principles of categorical perception and its underlying bases, including the sweep, magnitude, and symmetry of adaptation, are discussed. The principal findings of these studies provide new data on hue perception which strikingly parallel findings in speech perception.  相似文献   
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Although current theories of memory emphasize the fact that learning is an active process, there is little consensus on the role of active learning. This paper attempts to provide a more precise characterization of active learning in the acquisition of computer skills. The analysis of verbal protocols suggests that active learning varies on at least two dimensions: schema orientation and learning strategy. Schema orientation refers to the type of information the learner is acquiring and varies from relational information to procedural information. Learning strategy describes how the information is acquired. Some people prefer to be internally driven and form their own plans for learning. Others are externally driven and allow the instructional materials to guide their learning. These differences need to be taken into account in describing learning and in designing instructional materials.  相似文献   
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Simulations of space use by animals were run to determine the relationship among home range area estimates, variability, and sample size (number of locations). As sample size increased, home range size increased asymptotically, whereas variability decreased among mean home range area estimates generated by multiple simulations for the same sample size. Our results suggest that field workers should ascertain between 100 and 200 locations in order to estimate reliably home range area. In some cases, this suggested guideline is higher than values found in the few published studies in which the relationship between home range area and number of locations is addressed. Sampling differences for small species occupying relatively small home ranges indicate that fewer locations may be sufficient to allow for a reliable estimate of home range. Intraspecific variability in social status (group member, loner, resident, transient), age, sex, reproductive condition, and food resources also have to be considered, as do season, habitat, and differences in sampling and analytical methods. Comparative data still are needed.  相似文献   
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