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981.
Butler LD Seagraves DA Desjardins JC Azarow J Hastings A Garlan RW DiMiceli S Winzelberg A Spiegel D 《CNS spectrums》2002,7(8):597-603
This article reports on the planning, development, and implementation of a large national Internet-based panel study of how Americans are coping with the terrorist attacks of September 11, 2001. The study was designed to determine predictors and correlates of risk and resilience, both cross-sectionally and longitudinally. In order to acquire timely and meaningful data, we developed/adapted an extensive set of measures, obtained human subjects approval, and posted a research Web site just 17 days after the attacks. This article describes the major hurdles we confronted and the guidelines we recommend regarding these topics, including the methodological trade-offs inherent in Internet-based research, information technology requirements and tribulations, human subjects issues, selection of measures and securing permission for their use, and the challenges of participant recruitment. We also discuss issues that we did not anticipate, including the survey intervention. We focus not on findings, but on the concrete procedural, administrative, technical, and scientific challenges we encountered and the solutions we devised under considerable time and resource pressures. 相似文献
982.
Mathew SJ Coplan JD Smith EL Scharf BA Owens MJ Nemeroff CB Mann JJ Gorman JM Rosenblum LA 《Stress (Amsterdam, Netherlands)》2002,5(3):185-193
Adolescent bonnet macaques nursed as infants by mothers facing unpredictable requirements for food procurement (variable foraging demand, VFD) display persistent neurobiological disturbances. This study examined the long-term neurochemical and behavioral effects of adverse rearing initiated later in infancy than in previous cohorts of subjects to test the hypothesis that the timing of an early adverse experience would influence patterns of biobehavioral outcome. Cisternal cerebrospinal fluid (CSF) monoamine and corticotropin-releasing factor (CRF) concentrations were obtained from 20 bonnet macaques (11 VFD-reared and 9 normally reared controls) approximately 2 years after the end of differential rearing. VFD-reared primates displayed on multiple samplings significantly lower CSF CRF concentrations and higher CSF 5-hydroxyindoleacetic acid (5-HIAA) concentration compared to controls. In the VFD-reared, significant inverse correlations between CRF and all three monoamines were found (5-HIAA, 3-methoxy-4-hydroxyphenethyleneglycol and homovanillic acid), most prominently for 5-HIAA. In controls, but not VFD-reared subjects, CSF CRF was positively correlated with changes in "gregariousness" upon presentation of a fear stimulus. VFD-reared subjects displayed greater baseline hierarchical engagement than controls. In contrast to prior findings, in which rearing under VFD conditions at an earlier age led to increased CSF CRF compared with controls, CSF CRF was lower after later exposure to VFD rearing than in controls. Thus, the timing of exposure to VFD conditions early in life evidently determines whether CSF CRF was found to be elevated or decreased, within the context of increased serotonin metabolism, during the course of primate maturation. 相似文献
983.
Gerson AC Butler R Moxey-Mims M Wentz A Shinnar S Lande MB Mendley SR Warady BA Furth SL Hooper SR 《Mental retardation and developmental disabilities research reviews》2006,12(3):208-215
Given the rise in chronic kidney disease (CKD) in both children and adults, CKD has recently been targeted as a public health priority. Childhood onset kidney disease is generally a noncurable and progressive condition that leads to kidney failure by early adulthood. Fortunately, improved identification of kidney problems allows for early intervention, which is thought to slow progression toward end-stage renal disease. In addition, medical interventions for pediatric end-stage renal disease have also improved, allowing children to take advantage of lifesaving renal replacement treatments such as dialysis and kidney transplantation. In spite of improvements in identification and treatment, CKD causes both direct and indirect insults to a variety of organ systems. This paper reviews recently published studies pertaining to the neurocognitive and psychosocial impact of CKD on children of various ages and at various stages of kidney failure. Specific attention is focused on summarizing peer reviewed research that describes associations between kidney functioning and cognitive functioning, language acquisition, visual spatial abilities, memory, and executive functioning. In addition, peer reviewed research describing psychosocial outcomes associated with CKD related to academic achievement, social-behavioral functioning, and quality of life are summarized. The authors also identified disease-specific factors that likely mediate neurocognitive outcomes (e.g., anemia, hypertension, cardiovascular) and endorse the importance of continued interdisciplinary research collaborations that will provide a better understanding of the mechanisms responsible for improved neurocognitive functioning after transplantation. The authors conclude this review by describing a multicenter, prospective, longitudinal, National Institutes of Health funded study that is currently examining the developmental outcomes of children with mild to moderate CKD. The authors speculate that the Chronic Kidney Disease in Children Prospective Cohort Study (CKiD) findings will provide additional evidence-based guidance for clinicians and researchers working with children and adolescents with deteriorating kidney function to improve medical and developmental outcomes. 相似文献
984.
Jeremy D. Finn 《Sex roles》1980,6(1):9-26
Through their organization and curricula, schools either promote separate roles for males and females or operate to minimize differences. This study describes sex differences in science and reading achievement and attitudes for nationwide samples of 14-year-old children in the United States, Sweden, and England. There are largely the same sex differences in all three countries: Male and female pupils have similar reading skills, while girls have more positive reading habits; males outperform females in science, with the smallest difference observed for biology; males have more positive attitudes toward science, except that females believe science to be at least as important a topic as boys do. There is no noteworthy increase in sex distinctions with one more year of schooling, from grade 8 to grade 9. However, in English coeducational schools, girls show a deceleration in science and vocabulary achievement relative to their male peers. Girls in English one-sex schools exceed their male counterparts in reading and several science subjects. It is hypothesized that the role of successful female teachers and peers, and the absence of social pressure from boys, may facilitate girls' learning in these areas. A study is proposed of specific school practices and the ways in which they determine sex discrepancies.An earlier version of this article was presented to the annual meeting of the American Educational Research Association, San Francisco, April 1976. The author is grateful to Heidi Wolfstetter-Kausch for assistance in researching background material for the article. 相似文献
985.
Alexandra M. Harrison Nadia Bruschweiler-Stern Karlen Lyons-Ruth Alexander C. Morgan Jeremy P. Nahum Louis Sander Daniel N. Stern Edward Z. Tronick 《Infant mental health journal》1998,19(3):309-314
The analysis of a girl from ages 3 to 5 years old offers a clinical illustration of an alternative theory of change. In this theory the process of change is organized around nodal points of exchange between patient and analyst, designated as “now moments” and “moments of meeting.” In the case presented, these moments were preceded by an intensification of affect and were accompanied by a sense of openness and ambiguity. As often as not they were nonverbal and sometimes did not even involve symbolic representation. The process resulted in a progressively expanded repertoire of ways of being together and ways of doing things together. In a parallel and mutually influencing track, the child was telling me a story that gave meaning to her world, and increased the coherence of her sense of self. © 1998 Michigan Association for Infant Mental Health 相似文献
986.
987.
Philosophical Studies - We show that, contrary to conventional wisdom, Frege’s distinction between sense and reference does not reconcile a classical logic of identity with apparent... 相似文献
988.
Evan M. Palmer Michael J. Van Wert Todd S. Horowitz Jeremy M. Wolfe 《Attention, perception & psychophysics》2001,81(1):47-60
In visual search tasks, observers can guide their attention towards items in the visual field that share features with the target item. In this series of studies, we examined the time course of guidance toward a subset of items that have the same color as the target item. Landolt Cs were placed on 16 colored disks. Fifteen distractor Cs had gaps facing up or down while one target C had a gap facing left or right. Observers searched for the target C and reported which side contained the gap as quickly as possible. In the absence of other information, observers must search at random through the Cs. However, during the trial, the disks changed colors. Twelve disks were now of one color and four disks were of another color. Observers knew that the target C would always be in the smaller color set. The experimental question was how quickly observers could guide their attention to the smaller color set. Results indicate that observers could not make instantaneous use of color information to guide the search, even when they knew which two colors would be appearing on every trial. In each study, it took participants 200–300 ms to fully utilize the color information once presented. Control studies replicated the finding with more saturated colors and with colored C stimuli (rather than Cs on colored disks). We conclude that segregation of a display by color for the purposes of guidance takes 200–300 ms to fully develop. 相似文献
989.
990.