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991.
Calderón-Garcidueñas L Engle R Mora-Tiscareño A Styner M Gómez-Garza G Zhu H Jewells V Torres-Jardón R Romero L Monroy-Acosta ME Bryant C González-González LO Medina-Cortina H D'Angiulli A 《Brain and cognition》2011,77(3):345-355
Exposure to severe air pollution produces neuroinflammation and structural brain alterations in children. We tested whether patterns of brain growth, cognitive deficits and white matter hyperintensities (WMH) are associated with exposures to severe air pollution. Baseline and 1 year follow-up measurements of global and regional brain MRI volumes, cognitive abilities (Wechsler Intelligence Scale for Children-Revised, WISC-R), and serum inflammatory mediators were collected in 20 Mexico City (MC) children (10 with white matter hyperintensities, WMH+, and 10 without, WMH−) and 10 matched controls (CTL) from a low polluted city. There were significant differences in white matter volumes between CTL and MC children - both WMH+ and WMH− - in right parietal and bilateral temporal areas. Both WMH− and WMH+ MC children showed progressive deficits, compared to CTL children, on the WISC-R Vocabulary and Digit Span subtests. The cognitive deficits in highly exposed children match the localization of the volumetric differences detected over the 1 year follow-up, since the deficits observed are consistent with impairment of parietal and temporal lobe functions. Regardless of the presence of prefrontal WMH, Mexico City children performed more poorly across a variety of cognitive tests, compared to CTL children, thus WMH+ is likely only partially identifying underlying white matter pathology. Together these findings reveal that exposure to air pollution may perturb the trajectory of cerebral development and result in cognitive deficits during childhood. 相似文献
992.
Vanessa B. Sheppard Kristi D. Graves Juleen Christopher Alejandra Hurtado-de-Mendoza Costellia Talley Karen Patricia Williams 《Journal of genetic counseling》2014,23(3):311-322
Genetic counseling and testing for hereditary breast cancer have the potential benefit of early detection and early interventions in African American women. However, African American women have low use of these services compared to White women. We conducted two focus groups with African American women diagnosed with breast cancer (affected group, n?=?13) and women with at least one first-degree relative with breast/ovarian cancer (unaffected group, n?=?8). A content analysis approach was employed to analyze interview data. Breast cancer survivors had more knowledge about genetic counseling and testing than participants who were unaffected with cancer. However, knowledge about genetic counseling was limited in both groups. Barriers to pursuing genetic counseling and testing included poor understanding of the genetic counseling and testing process, fear of carrying the mutation, concerns about discrimination, and cost. Motivators to participate in genetic counseling and testing included desire to help family members, insurance coverage, and potential of benefiting the larger African American community. Education efforts are needed to increase genetic counseling and testing awareness in the African American community. 相似文献
993.
Richard T. Liu Lauren B. Alloy Becky M. Mastin James Y. Choi Elaine M. Boland Abigail Jenkins 《Anxiety, stress, and coping》2014,27(6):695-711
Background and Objectives: Although there is supporting evidence for the stress generation hypothesis (i.e., the tendency for depression-prone individuals to experience more negative dependent events influenced by their behaviors and characteristics), additional research is required to advance current understanding of the specific types of dependent events relevant to this effect. The present study elaborated on the stress generation hypothesis, in which the content of negative dependent events experienced by individuals is contingent upon, and matches, the nature of their particular vulnerabilities. This extension was tested within the context of Cole's competency-based model of depression. Design: Participants (n = 185) were assessed at two time-points separated by a four-month interval. Methods: Self-perceived competence in academic, social, and appearance domains at the initial time-point were examined in relation to negative life events prospectively occurring over the four-month follow-up period, assessed using the “contextual threat” method. Results: Partial support was obtained for vulnerability-specific stress generation. Stress-generation specificity was found for self-perceived competence in appearance and academic domains, but not for self-perceived social competence. Conclusions: The current findings are consistent with the possibility of a more complex relation between self-perceived social competence and domain-congruent stress generation. Individuals may be more likely to experience negative dependent events in domains matching their specific vulnerabilities. 相似文献
994.
Benjamin A. McDunn Aisha P. Siddiqui James M. Brown 《Psychonomic bulletin & review》2014,21(2):370-375
Boundary extension (BE) is a remarkably consistent visual memory error in which participants remember seeing a more wide-angle image of a scene than was actually viewed (Intraub & Richardson, Journal of Experimental Psychology: Learning, Memory, and Cognition 15:179–187, 1989). Multiple stimulus factors are thought to contribute to the occurrence of BE, including object recognition, conceptual knowledge of scenes, and amodal perception at the view boundaries (Intraub, Wiley Interdisciplinary Reviews: Cognitive Science 3:117–127, 2012). In the present study, we used abstract scenes instead of images of the real world, in order to remove expectations based on semantic associations with objects and the schematic context of the view. Close-angle and wide-angle scenes were created using irregular geometric shapes rated by independent observers as lacking any easily recognizable structure. The abstract objects were tested on either a random-dot or a blank background in order to assess the influence of implied continuation of the image beyond its boundaries. The random-dot background conditions had background occlusion cues either present or absent at the image border, in order to test their influence on BE in the absence of high-level information about the scenes. The results indicate that high-level information about objects and schematic context is unnecessary for BE to occur, and that occlusion information at the image boundary also has little influence on BE. Contrary to previous studies, we also found clear BE for all conditions, despite using scenes depicting undetailed objects on a blank white background. The results highlighted the ubiquitous nature of BE and the adaptability of scene perception processes. 相似文献
995.
Slepian, Masicampo, Toosi, and Ambady (Journal of Experimental Psychology: General, 141, 619–624, 2012, Study 1) found that individuals recalling and writing about a big, meaningful secret judged a pictured hill as steeper than did those who recalled and wrote about a small, inconsequential secret (with estimates unrelated to physical effort unaffected). From an embodied cognition perspective, this result was interpreted as suggesting that important secrets weigh people down. Answering to mounting calls for the crucial need of independent direct replications of published findings to ensure the self-correcting nature of our science, we sought to corroborate Slepian et al.’s finding in two extremely high-powered, preregistered studies that were very faithful to all procedural and methodological details of the original study (i.e., same cover story, study title, manipulation, measures, item order, scale anchors, task instructions, sampling frame, population, and statistical analyses). In both samples, we were unsuccessful in replicating the target finding. Although Slepian et al. reported three other studies supporting the secret burdensomeness phenomenon, we advise that these three other findings need to be independently corroborated before the general phenomenon informs theory or health interventions. 相似文献
996.
ADHERENCE TO DISCRETE‐TRIAL INSTRUCTION PROCEDURES BY RURAL PARENTS OF CHILDREN WITH AUTISM
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Claire C. St. Peter Lashanna Y. Brunson James E. Cook Shrinidhi Subramaniam Nicholas A. Larson Mark Clingan Susannah G. Poe 《Behavioral Interventions》2014,29(3):200-212
Parents of children with autism spectrum disorders may not attempt treatment, even when effective treatment options are available. Little is known about how to improve frequency of attempts to implement treatment (‘treatment adherence’). We provided 32 rural parents of young children with autism spectrum disorders with either written or video training materials about how to implement discrete‐trial instruction and compared parental adherence between the written (control) and video (experimental) groups. Parents who received video instructions adhered to the training procedures to a significantly greater extent than did parents who received written instructions, suggesting that instruction format is a predictor of training success. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
997.
998.
The dual-use issue is often framed as a series of paralyzing ‘dilemmas’ facing the scientific community as well as institutions which support innovation. While this conceptualization of the dual-use issue can be useful in certain contexts (such as in awareness-raising and as part of educational activities directed at the scientific community) its usefulness is more limited when reflecting on the governance and politics of the dual-use issue. Within this paper, key shortcomings of the dilemma framing are outlined. It is argued that many of the issues raised in the most recent debates about ‘dual-use’ bird flu research remain unresolved. This includes questions about the trajectories of certain lines of research, as well as broader trends in the practice and governance of science. This leads to difficult questions about current approaches to the dual-use issue within the US, as well as internationally. 相似文献
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