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921.
Infants' response to maternal mirroring was investigated in 4‐month‐old infants. Mother–infant dyads participated in the still face and replay tasks. Infants were grouped by those whose mothers did and did not mirror their behavior in the interactive phases of the tasks. In the still face task, infants with maternal mirroring showed more attention, smiling, and positive vocalizations across the phases, although both groups of infants demonstrated the still‐face effect with attention and smiling. Infants' social bidding to the mother during the still‐face phase correlated with mothers' mirroring behavior. In the replay task, infants with maternal mirroring demonstrated carryover effects with smiling; infants without maternal mirroring showed no awareness of change in their mothers' behavior. In both the still face and replay tasks, infants with maternal mirroring were more engaged with their mothers. Results suggest that maternal mirroring of infants' behavior affects infants' detection of, and response to, reciprocal interaction.  相似文献   
922.
Beginning in the 1980s, Mexico's social and labour policies took a neoliberal turn which exacerbated inequalities, poverty and social exclusion. The change of policy course that has occurred over the past decade has so far failed to bring about a critical review of the country's economic model and its social consequences. The role of the State has been systematically cut back; social services have been outsourced to the market; and informal family‐based social protection has gained ground. Mexico's social model has thus been reduced to a system that is almost exclusively concerned with protection for those living in extreme poverty.  相似文献   
923.
Using longitudinal data from the Fragile Families and Child Well‐being Study (N = 1,162) and the National Evaluation of Welfare‐to‐Work Strategies (N = 1,308), we estimate associations between material and instrumental support available to low‐income mothers and young children’s socioemotional well‐being. In multivariate OLS models, we find mothers’ available support is negatively associated with children’s behavior problems and positively associated with prosocial behavior in both data sets; associations between available support and children’s internalizing and prosocial behaviors attenuate but remain robust in residualized change models. Overall, results support the hypothesis that the availability of a private safety net is positively associated with children’s socioemotional adjustment.  相似文献   
924.
925.
Studies investigating the connection between environmental factors and migration are difficult to execute because they require the integration of microdata and spatial information. In this article, we introduce the novel, publically available data extraction system Terra Populus (TerraPop), which was designed to facilitate population–environment studies. We showcase the use of TerraPop by exploring variations in the climate–migration association in Burkina Faso and Senegal based on differences in the local food security context. Food security was approximated using anthropometric indicators of child stunting and wasting derived from Demographic and Health Surveys and linked to the TerraPop extract of climate and migration information. We find that an increase in heat waves was associated with a decrease in international migration from Burkina Faso, while excessive precipitation increased international moves from Senegal. Significant interactions reveal that the adverse effects of heat waves and droughts are strongly amplified in highly food insecure Senegalese departments.  相似文献   
926.
Poverty and vulnerability to poverty are major challenges facing developing countries and have attracted the attention of development economists and policy analysts in recent years. This study examined the relationship between household food poverty and vulnerability to food poverty in Nigeria based on data from Nigeria Living Standard Survey (NLSS) (2004) obtained from the National Bureau of Statistics. A least-cost technique associated with the food-energy-intake approach was used to compute zone-specific food poverty lines based on the food baskets common to each geo-political zone; the Foster–Greer–Thorbecke (FGT) poverty index was used in computing food poverty incidence; the three-step feasible generalised least squares (3FGLS) procedure was used in estimating the magnitude of vulnerability to food poverty; cross tabulation and Pearson’s product moment correlation coefficient were utilised for the purpose of analysing the association between household food poverty and vulnerability to food poverty. The food poverty incidence was 50.23 % while the vulnerability to food poverty incidence was 61.68 % and the vulnerability to food poverty/food poverty ratio was 1.228. The food poor were more vulnerable to food poverty than the non food poor. There was significant positive correlation between food poverty incidence and vulnerability to food poverty incidence even though the correlation was not very strong. Thus, policies and programmes that will optimally reduce food poverty and vulnerability to food poverty should be adopted in Nigeria; these should be targeted more on the food poor. This is a major way to break the yoke of underdevelopment in Nigeria.  相似文献   
927.
Randomized response models deal with stigmatizing variables appearing in health surveys. Additive and subtractive scrambling in split sample and double response yield unbiased mean and sensitivity estimators of high precision. The split sample method is protective of privacy. The double response method is as protective only conditionally. To achieve the maximum efficiency, the scrambling variables must be similar to each other and the probability of obtaining a true response must be as large as possible. The randomized response procedures yield more efficient estimates of the average total number of classes missed by university students.  相似文献   
928.
The conceptualization of ‘lifestyle mobilities’ has yet to fully account for the diversity within and across mobile communities in terms of leisure, travel, and identity. Lifestyle rock climbers, for example, maintain minimalist, hypermobile lifestyles in the full-time, non-professional pursuit of the sport. In an effort to interrogate lifestyle rock climbing within the broader conceptualization of lifestyle mobilities, this paper applies mesotheoretical ‘politics of mobility’ framework. It begins by tracing constellations of mobility and historical contexts within the rock climbing community more broadly. This is followed by an examination of the facets of a politics of mobility: motive force, speed, rhythm, route, experience, friction, turbulence, and remove, which together offer more nuanced understandings of the movement patterns and travel decisions of lifestyle climbing. However, to account for the community dynamics of lifestyle mobilities, there is a need to delve deeper and attend to the social relations that result from collective performances.  相似文献   
929.
We estimate a mixed logit model of the demand for local news service. Results provide evidence that suggest the representative consumer values more diverse news, more coverage of multicultural issues, and more information on community news, and has a distaste for advertising. Demand estimates are used to calculate the impact on consumer welfare from a marginal decrease in the number of independent television stations that lowers the amount of diversity, multiculturalism, community news, and advertising. Consumer welfare decreases, but the losses are smaller in large markets. For example, small‐market consumers lose $45 million annually while large‐market consumers lose $13 million. (JEL C9, C25, L13, L82, L96)  相似文献   
930.
Growing human populations make it imperative for ecologists to identify strategies to conserve biodiversity in human-dominated landscapes, such as cities. Effects of urbanization on birds are particularly well-studied, but questions remain regarding the best conservation approaches. Debate about the relative utility of focusing conservation efforts on nature reserves versus developed lands has focused largely on comparing species abundance or presence, with few studies addressing underlying behavioral or demographic mechanisms. Here we evaluated differences in avian reproductive success in nature reserves and matrix habitats to test the assumption that nest predation is lower within areas protected from development. Specifically, we investigated 1) whether nest survival differed in replicated pairs of forest parks and residential neighborhoods and 2) whether differences in nest survival were associated with changes in which species most frequently depredated nests. From April–August 2007–2014, we monitored nests of two native birds, American robin (Turdus migratorius) and northern cardinal (Cardinalis cardinalis), and video-documented nest predators in paired forest-matrix habitats in the Columbus, Ohio metropolitan area. We found similar rates of nest survival in the two habitats for both robins (Χ21?=?0.715, p?=?0.398, n?=?741 nests) and cardinals (Χ21?=?0.926, p?=?0.336, n?=?1156 nests), but interactions between predators and prey differed. In particular, domestic cats (Felis catus) were over five times as likely to depredate cardinal nests in matrix habitats versus forest parks (Χ21?=?7.24, simulated p?=?0.010; nforest?=?3, nmatrix?=?7). Our results suggest that at least in some circumstances, nest success of native birds may be equivalent between nature reserves and adjacent residential matrix habitats, and thus residential neighborhoods may contribute positively to bird conservation in urban landscapes.  相似文献   
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