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981.
The authors discuss potential confusion in conducting primary studies and meta-analyses on the basis of differences between groups. First, the authors show that a formula for the sampling error of the standardized mean difference (d) that is based on equal group sample sizes can produce substantially biased results if applied with markedly unequal group sizes. Second, the authors show that the same concerns are present when primary analyses or meta-analyses are conducted with point-biserial correlations, as the point-biserial correlation (r) is a transformation of d. Third, the authors examine the practice of correcting a point-biserial r for unequal sample sizes and note that such correction would also increase the sampling error of the corrected r. Correcting rs for unequal sample sizes, but using the standard formula for sampling error in uncorrected r, can result in bias. The authors offer a set of recommendations for conducting meta-analyses of group differences. 相似文献
982.
This study describes the development of the Home Environment Resources Scale, a Brazilian measure for families with children ages 6 to 12 years. The scale measures aspects of support for school achievement, made available to the child at home. A first version of the measure with 11 subscales was administered to 100 mothers or guardians of children with poor school achievement in a clinical setting. Analysis of the items in the first version resulted in a final version comprising 8 subscales with acceptable indices of internal consistency. Two validity studies were conducted. One aimed at verifying to what extent the Home Environment Resources Scale could discriminate the home environment of students referred to a mental health clinic on account of poor school performance. The sample included mothers of 53 referred and 23 nonreferred children. The two groups differed significantly in home resources and on four subscales. The other study assessed the validity, i.e., prediction of the academic outcome of children entering Grade 1. 70 children and their mothers participated. Results indicate that school achievement and social competence at school are mediated by family support. 相似文献
983.
Transitions in caregivers' use of paid home help: associations with stress appraisals and well-being
This study examines the associations between transitions in paid home care and stress appraisals and psychological well-being of family caregivers of dementia relatives. The sample consisted of 264 caregivers who completed up to 3 interviews during 1 year. Longitudinal analyses (i.e., generalized estimating equations) showed that the onset of paid home care was associated with increases in feelings of worry and strain and a worsening in positive affect. Ending paid home care was strongly associated with a decrease in depressive symptoms, whereas sustained use of paid home care was related to reduced overload. Several possible mechanisms for the complex relationship of paid home care and family caregivers' stress appraisals and well-being are discussed. 相似文献
984.
Ana Waleska P.C.?Mendon?aEmail author Libania Nacif?Xavier Vera Lucia Alves?Breglia Miriam Waidenfeld?Chaves Maria Teresa Cavalcanti?de Oliveira Cecília Neves?Lima Pablo S.M. Bispo?Dos Santos 《Studies in Philosophy and Education》2005,24(6):471-498
This article proposes to analyse some aspects of the appropriation of New School thinking in Brazil, particularly Deweyan pragmatism, in the 1950s and 1960s. The analysis is based on the assumption that the developmentalist ideology that punctuated the debate on the economic, political and social restructuring of the country in these two decades constituted fertile ground for the return and expansion of pragmatist thinking amongst Brazilian educators, articulating itself, sometimes in contradictory ways, with this ideology. The focus of the analysis will be on the writings of the group of educators which circulated around the figure of Anísio Teixeira, at the time director of the National Institute for Pedagogic Studies (INEP), an organ linked to the Ministry of Education and Culture (MEC), which set itself the task of producing research that would support public policy in the field of education, as well as constituting itself as a center for teacher education and the stimulus and development of innovative experiences in the public school system. The appropriation of Deweyan pragmatism, in this context, had a triple perspective: pragmatism as scientific method, implying a specific conception of science, particularly the social sciences, with emphasis on the application of scientific knowledge in the solution of practical problems; as a way of democratic life; and as a synonym for experimentalism, in the sphere of schooling. 相似文献
985.
Activation of adenosine receptors in the posterior cingulate cortex impairs memory retrieval in the rat 总被引:2,自引:0,他引:2
Pereira GS Rossato JI Sarkis JJ Cammarota M Bonan CD Izquierdo I 《Neurobiology of learning and memory》2005,83(3):217-223
Adenosine A1 and A2A receptor agonists and antagonists have been reported to alter learning and memory. The aim of our study was to investigate the involvement of adenosinergic system in memory retrieval into posterior cingulate cortex (PCC) of Wistar rats. To clarify this question, we tested specifics agonist and antagonists of adenosine A1 and A2A receptors in rats submitted to a one-trial inhibitory avoidance task. The stimulation of adenosine A1 and A2A receptors by CPA and CGS21680, respectively, impaired memory retrieval for inhibitory avoidance task, into PCC. These findings provide behavioral evidence for the role of adenosinergic system in the memory retrieval into PCC. 相似文献
986.
This literature review examined the characteristics and effectiveness of treatments dedicated exclusively to body image. A total of 18 studies met selection criteria. All but one involved at least one cognitive-behavioural therapy (CBT) condition and only three compared CBT to another treatment approach. Twelve studies were conducted with non-clinical, body dissatisfied, participants and only one focussed on eating disordered women. Overall, the interventions were highly effective in improving body image and psychological variables and, to a lesser extent, eating attitude and behaviour. Changes were generally maintained at follow-up. Given their efficacy, more controlled trials of stand-alone body image treatments in clinical populations are needed. Investigating approaches other than CBT may open fruitful avenues of body image treatment. 相似文献
987.
This study examined the development of infants' ability to perceive, learn, and remember the unique face-voice relations of unfamiliar adults. Infants of 2, 4, and 6 months were habituated to the faces and voices of 2 same-gender adults speaking and then received test trials where the faces and voices were synchronized yet mismatched. Results indicated that 4- and 6-month-olds, but not 2-month-olds, detected the change in face-voice pairings. Two-month-olds did, however, discriminate among the faces and voices in a control study. Results of a subsequent intermodal matching procedure indicated that only the 6-month-olds showed matching and memory for the face-voice relations. These findings suggest that infants' ability to detect the arbitrary relations between specific faces and voices of unfamiliar adults emerges between 2 and 4 months of age, whereas matching and memory for these relations emerges somewhat later, perhaps between 4 and 6 months of age. 相似文献
988.
This study explores multiple relational contexts that promote vulnerability and protection against early pregnancy in a potential risk group of Portuguese adolescents. A comparative analysis was made between two groups of female adolescents of low socioeconomic status: pregnant adolescents (n=57) and adolescents without a history of pregnancy (n=81). Results suggest that several variables belonging to different contexts-family and school and peer relations--are important in the characterization of the two groups. Lower levels of mother's overprotection and father's emotional support, presence of early pregnancy in adolescent's mother, lower level of emotional proximity to peer relations, and higher number of school failures are significantly associated with adolescent pregnancy. 相似文献
989.
Two studies investigated the impact of past ingroup experiences on individual aspirations and effort. Participants were told that in the past, members of their group had either been offered no opportunities (closed), few opportunities (token), or equal opportunities (open) to achieve a desired outcome. The results show that past group experiences determine responses to current opportunities and affect the perceived feasibility of individual success as well as individual performance. Exposure to a token system has different effects, depending on whether the group is historically advantaged or disadvantaged. Whereas those with a collective history of success see token mobility as a challenge and show superior performance, the same situation constitutes a threat to members of a historically disadvantaged group, who fail to take advantage of the opportunities offered to them and perform suboptimally. 相似文献
990.
Arrigo JM 《Science and engineering ethics》2004,10(3):543-572
Following the September 2001 terrorist attacks on the United States, much support for torture interrogation of terrorists
has emerged in the public forum, largely based on the “ticking bomb” scenario. Although deontological and virtue ethics provide
incisive arguments against torture, they do not speak directly to scientists and government officials responsible for national
security in a utilitarian framework. Drawing from criminology, organizational theory, social psychology, the historical record,
and my interviews with military professionals, I assess the potential of an official U.S. program of torture interrogation
from a practical perspective. The central element of program design is a sound causal model relating input to output. I explore
three principal models of how torture interrogation leads to truth: the animal instinct model, the cognitive failure model, and the data processing model. These models show why torture interrogation fails overall as a counterterrorist tactic. They also expose the processes that
lead from a precision torture interrogation program to breakdowns in key institutions—health care, biomedical research, police,
judiciary, and military. The breakdowns evolve from institutional dynamics that are independent of the original moral rationale.
The counterargument, of course, is that in a society destroyed by terrorism there will be nothing to repair. That is why the
actual causal mechanism of torture interrogation in curtailing terrorism must be elucidated by utilitarians rather than presumed. 相似文献