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231.
To identify the challenges that students must meet to engage in effective self-directed inquiry, a class was followed for three years, from the fourth through the sixth grades, as they engaged in a sequence of progressively more demanding inquiry activities. Students made substantial progress in understanding the objectives of inquiry, identifying questions, attending to evidence, identifying patterns, making controlled comparisons, interpreting increasingly complex data, supporting claims, and drawing justified conclusions. Retaining awareness of inquiry objectives and integrating influences of multiple variables in predicting outcomes were two areas that remained challenging. A comparison group of seventh graders who had not been involved in the program displayed strikingly different approaches to an inquiry task, indicating that the skills identified here are not ones that develop in the absence of appropriate kinds of educational experiences.  相似文献   
232.
This paper demonstrates experimentally that the mere fact that an alternative was chosen in the past increases the likelihood that it will be re-chosen in the future, when new alternatives are being offered. The experimental design consists of a new variation of the free-choice paradigm that is immune to Chen and Risen’s (2010) criticism of how results have been interpreted in previous studies of post-decision effects. An additional experiment indicates that once participants have chosen a particular alternative they view its characteristics more positively. I suggest that the new design can be used to study various aspects of the effect of past decisions on future ones. In the present paper, I apply it to show that the allocation of limited resources among various uses may be biased in favor of a particular use if it was preferred to another in a previous situation.  相似文献   
233.
Veterans from the conflicts in Afghanistan (Operation Enduring Freedom; OEF) and Iraq (Operation Iraqi Freedom; OIF) have reported elevated rates of alcohol consumption, and greater depression and posttraumatic stress disorder (PTSD) symptoms are associated with increased alcohol use. Presence of a spouse/partner, which has been associated with reduced drinking, may buffer the relationship between mental health symptoms and alcohol consumption. To examine this hypothesis, the current study utilized baseline survey data from OEF/OIF veterans (N = 325) enrolled in a brief alcohol intervention. Spouse/partner presence moderated the relationship between depression symptoms and alcohol consumption such that depression was positively associated with drinking for veterans without a spouse/partner. Exploratory analyses indicated that the relationship between depression and alcohol use may be particularly salient for veterans without a spouse/partner and a lower number of deployments. Spouse/partner presence did not moderate the relationship between PTSD symptoms and alcohol consumption. Implications of the findings are discussed.  相似文献   
234.
We examined how interpersonal justice from coworkers, the traditional justice facets (i.e., distributive, procedural, interpersonal, informational), and overall justice perceptions relate to employee psychological strain and turnover intentions in Canadian Armed Forces personnel. Specifically, we hypothesized that overall justice would mediate the relationships between the justice facets (including coworker justice) and strain, and strain would mediate the relationship between overall justice and turnover intent. We used a cross-sectional correlational design with personnel from 2 military units (total N = 218) as our sample. A 2-step structural equation modeling technique was used to evaluate our hypotheses. Support for our hypotheses was obtained with 1 exception: informational justice did not predict overall justice judgments. Our results suggest that employees’ reactions to individual justice events and different sources of justice exert their effects on strain and turnover intent indirectly through their impact on a global evaluation of justice in their work environment.  相似文献   
235.
EDITORIAL     
The aim of the present study was to evaluate the usefulness of Barkley’s (1997a) model of inhibition and executive functioning in describing the deficits associated with Attention Deficit Hyperactivity Disorder (ADHD). Besides group differences, the present study addressed the question of independent effects of inhibition and the other executive functions in discriminating between children with ADHD and controls and how well, in terms of sensitivity and specificity, these measures can classify the children into the correct group. The results showed that children with ADHD differed significantly from controls with regard to measures of inhibition as well as all other executive function measures, except repetition of hand movements. In logistic regression models, three different measures tapping inhibition, working memory and emotion regulation were shown to be significant independent predictors of group membership. The sensitivity for these three variables as a set was 76.2, the specificity was 90.5, with a total of 86% of the sample correctly classified. When excluding the parental rating of emotion regulation, the overall classification rate decreased some, but was still relatively high in comparison with previous studies within this area of research.  相似文献   
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This paper seeks to explore some of the effects of abuse by a mother on her very young son. It considers how the primitive capacity for coping with anxiety by splitting and projection has been rendered ineffectual, and how the structures that have evolved to compensate have profoundly affected the boy's emotional and mental capacities. In the first fifteen months of therapy, the boy has begun to make some tentative moves towards effective splitting and projection, with its hope of healthier growth. This hope is hard for him to bear, involving, as it must, searing depressive pain. There is consequently a powerful pull towards a pathological organization where omnipotence and omniscience offer, disastrously, an exciting and pain-free alternative. The boy's therapy and his therapist are exposed to the full impact of the omnipotent onslaught, and evolving ways of bearing this and continuing to think was not only essential for survival but, also, a major tool of the therapy.  相似文献   
239.
We used an intersectional minority stress perspective to examine the association between family/cultural stress and mental health among substance-using Mexican-Americans. Employing a unique longitudinal sample of 239 socioeconomically disadvantaged, non-injecting heroin-using Mexican-Americans from San Antonio, Texas, we examined how culturally relevant stressors are related to depression and suicidal ideation. First, we identified depression and suicidal ideation prevalence rates for this disadvantaged sample. Second, we determined how cultural stress is experienced over time using stress trajectories. Third, we evaluated how family/cultural stressors and stress trajectories are related to depression and suicidal ideation outcomes. Results showed high rates of baseline depression (24 %) and suicidal ideation (30 %). We used latent class growth analysis to identify three primary stress trajectories (stable, high but decreasing, and increasing) over three time points during 1 year. We found that the increasing stressors trajectory was associated with higher rates of depression and suicidal ideation, and that stress trajectories had unique relationships with mental illness. We also showed that baseline stressors, sum stressors, and high but decreasing stressors maintained positive associations with mental illness after controlling for baseline depression. Our results highlight the importance of focusing on within-group, culturally specific stressors and addressing both operant and cumulative stressors in the study of mental health for marginalized populations and suggest the importance of early intervention in minimizing stressors.  相似文献   
240.
Exaggeration of the vowel space in infant-directed speech (IDS) is well documented for English, but not consistently replicated in other languages or for other speech-sound contrasts. A second attested, but less discussed, pattern of change in IDS is an overall rise of the formant frequencies, which may reflect an affective speaking style. The present study investigates longitudinally how Dutch mothers change their corner vowels, voiceless fricatives, and pitch when speaking to their infant at 11 and 15 months of age. In comparison to adult-directed speech (ADS), Dutch IDS has a smaller vowel space, higher second and third formant frequencies in the vowels, and a higher spectral frequency in the fricatives. The formants of the vowels and spectral frequency of the fricatives are raised more strongly for infants at 11 than at 15 months, while the pitch is more extreme in IDS to 15-month olds. These results show that enhanced positive affect is the main factor influencing Dutch mothers’ realisation of speech sounds in IDS, especially to younger infants. This study provides evidence that mothers’ expression of emotion in IDS can influence the realisation of speech sounds, and that the loss or gain of speech clarity may be secondary effects of affect.  相似文献   
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