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71.
Michelle Bosquet Enlow Katrina L. Devick Kelly J. Brunst Lianna R. Lipton Brent A. Coull Rosalind J. Wright 《Infancy》2017,22(4):492-513
Little research has examined the impact of maternal lifetime trauma exposure on infant temperament. We examined associations between maternal trauma history and infant negative affectivity and modification by prenatal cortisol exposure in a sociodemographically diverse sample of mother–infant dyads. During pregnancy, mothers completed measures of lifetime trauma exposure and current stressors. Third‐trimester cortisol output was assessed from maternal hair. When infants were 6 months old, mothers completed the Infant Behavior Questionnaire‐Revised. In analyses that controlled for infant sex and maternal age, education, race/ethnicity, and stress during pregnancy, greater maternal trauma exposure was associated with increased infant distress to limitations and sadness. Higher and lower prenatal cortisol exposure modified the magnitude and direction of association between maternal trauma history and infant rate of recovery from arousal. The association between maternal trauma history and infant distress to limitations was somewhat stronger among infants exposed to higher levels of prenatal cortisol. The analyses suggested that maternal lifetime trauma exposure is associated with several domains of infant negative affectivity independently of maternal stress exposures during pregnancy and that some of these associations may be modified by prenatal cortisol exposure. The findings have implications for understanding the intergenerational impact of trauma exposure on child developmental outcomes. 相似文献
72.
73.
Tommy Wright 《The American statistician》2013,67(4):217-224
We present a surprising though obvious result that seems to have been unnoticed until now. In particular, we demonstrate the equivalence of two well-known problems—the optimal allocation of the fixed overall sample size n among L strata under stratified random sampling and the optimal allocation of the H = 435 seats among the 50 states for apportionment of the U.S. House of Representatives following each decennial census. In spite of the strong similarity manifest in the statements of the two problems, they have not been linked and they have well-known but different solutions; one solution is not explicitly exact (Neyman allocation), and the other (equal proportions) is exact. We give explicit exact solutions for both and note that the solutions are equivalent. In fact, we conclude by showing that both problems are special cases of a general problem. The result is significant for stratified random sampling in that it explicitly shows how to minimize sampling error when estimating a total TY while keeping the final overall sample size fixed at n; this is usually not the case in practice with Neyman allocation where the resulting final overall sample size might be near n + L after rounding. An example reveals that controlled rounding with Neyman allocation does not always lead to the optimum allocation, that is, an allocation that minimizes variance. 相似文献
74.
75.
Respiratory illness is an important childhood illness and a significant cause of infant mortality. This study examined the
relationship between neighbourhood level variables and rates of respiratory illness for children less than 2 years of age,
born in Saskatoon between 1992 and 1994. Rates of respiratory illness, as measured by proportion of children hospitalized
and frequency of hospitalization and ambulatory visits to physicians, were higher among infants living in socially disadvantaged
neighbourhoods. Multivariate predictive models for rates of respiratory illness support the research hypothesis that housing
characteristics, in the presence of other neighbourhood characteristics, have a significant impact on determining the rates
of respiratory illness among Saskatoon children. 相似文献
76.
Schmied V Cooke M Gutwein R Steinlein E Homer C 《Women and birth : journal of the Australian College of Midwives》2008,21(3):99-105
BACKGROUND: In Australia and internationally, women report high levels of dissatisfaction with hospital-based postnatal care. AIM: To design and implement strategies to improve hospital-based postnatal care at a Sydney metropolitan hospital. METHOD: This was an Action Research study. In Phase One, midwives considered the literature and participated in group discussions and interviews to determine their perceptions of postnatal care and the factors that facilitate or hinder the provision of quality care. In Phase Two, midwives participated in 12 working group meetings to design strategies to improve care. RESULTS: Several important principles of postnatal care were described, including building a relationship with women, meeting their individual needs, being flexible in approach and providing continuity of care. 'Listening to women', 'being there,' and 'normalising experiences and expectations' were believed to be critical to achieving these principles. A key strategy 'One to One Time' was designed to provide women with an uninterrupted period of time each day with a midwife who was available to listen to their needs and concerns and discuss issues related to their health and that of their baby. CONCLUSION: Midwives designed and implemented strategies that they believed would improve in-hospital postnatal care. 相似文献
77.
Arrivals of new immigrants into the south Florida area have put increased pressure on housing markets and fostered renewed efforts to provide more affordable housing. Many view household extension largely as a response to the lack of a sufficient amount of affordable housing. This paper examines the nature, proportion and housing condition of nuclear and extended households in the Miami-Fort Lauderdale area. The study also investigates how the incidence and housing situation of extended households has changed during the period from 1986 to 1990. This study illustrates that extended families in the Miami-Fort Lauderdale area are not uniformly worse off than nuclear families, given ethnicity and income level. While the area's housing problems require attention, some of that attention should be focused on removing institutional barriers to household extension and to providing broader housing choices for minority ethnic groups. 相似文献
78.
Adolescent peer crowds such as Punks and Goths are mainly identified by their strikingly unusual or even shocking appearances. Although many studies find these crowds, few have tried to explain why some youths take on these startling or shocking appearances. We hypothesized that an off‐putting appearance is a way to cope with behavioral inhibition by limiting social contacts. Using data from 1,200 7th–11th graders, we compared peer crowds characterized by their startling appearance (“Radical” crowds) with three theoretically relevant comparison groups. Results showed that youths affiliating with Radical crowds were more inhibited than other youths, including those in crowds previously shown to be shy or socially anxious. Inhibited Radicals, however, had poorer emotional adjustment than inhibited youths in other crowds. If Radical styles are a way for inhibited youths to cope by limiting social contacts, the strategy does not seem to be beneficial for emotional adjustment. 相似文献
79.
Ecological research can augment restoration practice in urban areas degraded by invasive species—examples from Chicago Wilderness 总被引:1,自引:1,他引:0
Liam Heneghan Lauren Umek Brad Bernau Kevin Grady Jamie Iatropulos David Jabon Margaret Workman 《Urban Ecosystems》2009,12(1):63-77
Urban biodiversity conservation needs a firm scientific foundation, one that draws upon active and regionally calibrated research
programs. Until recently this foundation has not existed. In this paper we examine the way in which the emerging discipline
of restoration ecology in an urban context can learn from the experiences of ongoing restoration projects and in turn how
novel insights from research of urban soils can help these projects define and reach their goals. Limitations on collaboration
between academic researchers and practitioners continues be problematic. We discuss a model whereby this impediment may be
removed. A case study of Rhamnus cathartica, an invader of Midwestern woodlands which modifies some important soil ecosystem properties will be used to illustrate the
potential for engagement between research and practice. 相似文献
80.
Employment and earnings of foreign-born scientists and engineers 总被引:1,自引:1,他引:0
Espenshade Thomas J. Usdansky Margaret L. Chung Chang Y. 《Population research and policy review》2001,20(1-2):81-105
Population Research and Policy Review - 相似文献