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151.
As compared with conventional vaccine production systems, plant-made vaccines (PMVs) are said to enjoy a range of advantages including cost of production and ease of storage for distribution in developing countries. In this article, we introduce the science of PMV production, and address ethical issues associated with development and clinical testing of PMVs within three interrelated domains: PMVs as transgenic plants; PMVs as clinical research materials; and PMVs as agents of global health. We present three conclusions: first, while many of the ethical issues raised by PMVs are familiar, PMVs add a new dimension to old issues, and raise some novel issues for ethicists and policy-makers; secondly, it is premature to promise broad applicability of PMVs across the developing world without having demonstrated their feasibility; thirdly, in particular, proponents of PMVs as a solution to global health problems must, as a condition of the ethical conduct of their research, define the commercial feasibility of PMVs for distribution in the developing world. 相似文献
152.
Schneider KJ 《The American psychologist》2006,61(3):258; discussion 259-258; discussion 261
153.
There is a growing trend toward later toilet training of typically developing children. This trend is a problem for caregivers and professionals who work with young children, because it is associated with a number of costs and health risks in child-care settings. Results of a recent study (Tarbox, Williams, & Friman, 2004) suggest that wearing underwear may facilitate the development of toileting skills. Based on these findings, we examined the effects of wearing disposable diapers, disposable pull-on training pants, and underwear on urinary continence of 5 typically developing toddlers in a child-care setting. Underwear decreased incontinence and increased continent urinations for 2 of the 5 participants, produced no improvement in 2 participants, and when combined with increased fluid intake and longer sitting periods, produced some favorable trends for the 5th participant. 相似文献
154.
Thompson R Dubowitz H English DJ Nooner KB Wike T Bangdiwala SI Runyan DK Briggs EC 《Suicide & life-threatening behavior》2006,36(2):167-181
This study examined concordance between adult and child reports of child suicidality using a sample of 1,046 8-year-old children at risk for, or having experienced, maltreatment. Concordance was low with both caregivers and teachers. For children reporting no suicidality, caregiver-child agreement was associated with few transitions in caregiver and low social withdrawal and aggression, and teacher-child agreement was associated with non-White ethnicity, good academic performance, and low thought problems. For children reporting suicidality, care-giver-child agreement was associated with perceptions of child mental health needs, aggression, and somatic complaints, and teacher-child agreement was associated with thought problems. 相似文献
155.
The focus of this study was to identify factors that differentiate women drug abusers who had experienced suicidal ideation from those who did not. Face-to-face interviews were conducted with 221 cocaine-using women in Atlanta, GA, 88 (39.8%) of whom reported thinking about committing suicide at least once during the 90 days prior to interview and 133 (60.2%) of whom did not. Multivariate logistic regression was used to identify predictors of suicidal ideation, and post hoc goodness-of-fit tests were conducted to assess the robustness of final models derived. Model 1 excluded all psychosocial functioning measures and Model 2 included these items. Both models showed that suicidal ideation was more common among women who were unemployed, had been abused sexually, engaged in sexual relations to cope with stresses, or had less helpful relatives. In addition, Model 1 revealed a heightened risk for women experiencing financial problems and those who had a previous mental health diagnosis, whereas Model 2 showed an elevated risk among women who experienced anxiety and those who had lower levels of self-esteem. These findings suggest the need for prevention and intervention programs that target at-risk women, and for such programs to include an emphasis on suicidal ideation in addition to focusing on risk factors that are addressed more commonly. 相似文献
156.
Norman JF Crabtree CE Herrmann M Thompson SR Shular CF Clayton AM 《Perception & psychophysics》2006,68(1):94-101
In two experiments, we investigated the ability of younger and older observers to perceive and discriminate 3-D shape from static and dynamic patterns of binocular disparity. In both experiments, the younger observers' discrimination accuracies were 20% higher than those of the older observers. Despite this quantitative difference, in all other respects the older observers performed similarly to the younger observers. Both age groups were similarly affected by changes in the magnitude of binocular disparity, by reductions in binocular correspondence, and by increases in the speed of stereoscopic motion. In addition, observers in both age groups exhibited an advantage in performance for dynamic stereograms when the patterns of binocular disparity contained significant amounts of correspondence "noise." The process of aging does affect stereopsis, but the effects are quantitative rather than qualitative. 相似文献
157.
This study examined the impact of changes in level of current grief over time on changes in memory for past grief. Following from previous work on the impact of current affective state on memory for past affectively salient events, bereaved individuals who underwent a greater reduction in grief over time were expected to show a similar pattern of changes in memory for past grief. A sample of conjugally bereaved participants completed measures of current grief and memory for past grief at the time of the loss of their spouse at each of the 2, 6, 13, and 30 month post-loss time periods. As predicted, those who reported greater reduction in grief over the course of the study were more likely to remember their past grief as progressively less severe relative to those who underwent less reduction in grief over time. A nonrecursive causal model analysis verified that changes in memory for past grief were explained by changes in current grief. These results were discussed in terms of contemporary reconstructive memory accounts of the effect of affective state on memory. 相似文献
158.
Yaron G. Rabinowitz Mark G. Hartlaub Ericka C. Saenz Larry W. Thompson Dolores Gallagher-Thompson 《Journal of religion and health》2010,49(4):498-512
The current study explored the relationship between religious coping and cumulative health risk associated with health behavior
patterns in a sample of 256 Latina and Caucasian female caregivers of elderly relatives with dementia. Primary analyses examined
the relationship between religious coping (both positive and negative) and an overall index of cumulative health risk. Secondary
analyses were conducted on the individual health behaviors subsumed in the broader index. Findings revealed that negative
religious coping was significantly associated with increased cumulative health risk. Positive religious coping was predictive
of decreased cumulative health risk among Latina caregivers but not among Caucasians. Negative religious coping was significantly
associated with both an increased likelihood for weight gain and increased dietary restriction. Positive religious coping
was associated with decreased likelihood for weight gain in Latinas. Implications for both caregivers and clinicians are discussed. 相似文献
159.
Kirby Deater‐Deckard Charles Beekman Zhe Wang Jungmeen Kim Stephen Petrill Lee Thompson Laura DeThorne 《Journal of personality》2010,78(3):991-1010
ABSTRACT We examined mothers' ratings of children's affective and behavioral aspects of approach tendencies and links with overt aggressive behavior problems while considering the genetic etiology of these processes. Approach/positive anticipation (AP), frustration/anger (FA), and overt aggression in 4–9‐year‐olds were assessed using mothers' reports in a diverse national sample (n=992) and a sample of same‐sex twins (n=195 pairs). AP and FA were positively correlated with each other and with overt aggression (r from .2 to .5), and these associations were very similar for boys and girls. AP and FA provided overlapping as well as independent statistical prediction of aggression. AP statistical prediction of aggression was substantially mediated by FA, an effect that was accounted for by underlying genetic and nonshared environmental influences. 相似文献
160.
Individual vocal recognition behaviors in songbirds provide an excellent framework for the investigation of comparative psychological and neurobiological mechanisms that support the perception and cognition of complex acoustic communication signals. To this end, the complex songs of European starlings have been studied extensively. Yet, several basic parameters of starling individual vocal recognition have not been assessed. Here we investigate the temporal extent of song information acquired by starlings during vocal recognition learning. We trained two groups of starlings using standard operant conditioning techniques to recognize several songs from two conspecific male singers. In the first experiment we tested their ability to maintain accurate recognition when presented with (1) random sequences of 1–12 motifs (stereotyped song components) drawn from the training songs, and (2) 0.1–12-s excerpts of continuous song drawn from the training songs. We found that song recognition improved monotonically as more vocal material is provided. In the second experiment, we systematically substituted continuous, varying length regions of white noise for portions of the training songs and again examined recognition accuracy. Recognition remained above chance levels for all noise substitutions tested (up to 91% of the training stimulus) although all but the smallest substitutions led to some decrement in song recognition. Overall, above chance recognition could be obtained with surprisingly few motifs, short excerpts of song, and in the absence of large portions of the training songs. These results suggest that starlings acquire a representation of song during individual vocal recognition learning that is robust to perturbations and distributed broadly over large portions of these complex acoustic sequences. 相似文献