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101.
102.
《Social Development》2018,27(2):322-334
During infancy, cardiac vagal modulation has been associated with attentional and social engagement behaviors. While studies have shown that infants display a behavioral repertoire that enables them to interact with others by being able to regulate themselves in order to attend to and to discriminate emotional and social cues, vagal modulation to sensory stimuli and its association with behavioral outcomes at early ages remains to be addressed. In this study, we analyzed the cardiac vagal response of 1‐month‐old infants to two auditory stimuli intensities and whether vagal response was associated with social interactive and self‐regulatory abilities. Therefore, we recorded cardiac and respiratory physiological responses in 28 infants using a Biopac System. Neurobehavioral assessment was performed using the Neonatal Behavioral Assessment Scale. We observed increased respiratory sinus arrhythmia (RSA) amplitude to both auditory stimuli intensities when compared to baseline. No intensity effect was found for the RSA response. Additionally, we observed that higher RSA amplitude to both auditory stimuli was positively correlated with adjusted self‐regulatory behaviors, suggesting a convergence between multiple measures assessing infants' state regulation. Results are discussed in light of 1‐month‐old infants' auditory stimuli processing and its implications for regulatory behaviors and the emergent social‐like behaviors.  相似文献   
103.
Sweden is seen as a typical example of a social democratic welfare regime, with universal and generous welfare policies. However, in the last decades, there have been substantial reductions in the Swedish provision of care for older people. This study aimed to examine trends in sources of care‐receipt in older people (77+) living in their own home and with a perceived need for help with two specific tasks: house cleaning and/or food shopping. Trends in care‐receipt were examined in relation to gender, living alone, having children and socio‐economic position. Data from the 1992, 2002 and 2011 data collection waves of the national study, Swedish Panel Study of Living Conditions of the Oldest Old (SWEOLD), were used. Response rates varied between 86 and 95 per cent, and the sample represents the population well. Trends and differences between groups were explored in bivariate and logistic regression analyses. There was a reduction in formal care‐receipt regarding house cleaning and food shopping over the study period. It was more common for women than men to receive formal care, and more common for men than women to receive informal care. Reductions in formal care have affected older women more than older men. Still, living alone was the most influential factor in care‐receipt, associated with a greater likelihood of formal care‐receipt and a lower likelihood of informal care‐receipt. It can be concluded that public responsibility for care is becoming more narrowly defined in Sweden, and that more responsibility for care is placed on persons in need of care and their families.  相似文献   
104.
The Hartley‐Rao‐Cochran sampling design is an unequal probability sampling design which can be used to select samples from finite populations. We propose to adjust the empirical likelihood approach for the Hartley‐Rao‐Cochran sampling design. The approach proposed intrinsically incorporates sampling weights, auxiliary information and allows for large sampling fractions. It can be used to construct confidence intervals. In a simulation study, we show that the coverage may be better for the empirical likelihood confidence interval than for standard confidence intervals based on variance estimates. The approach proposed is simple to implement and less computer intensive than bootstrap. The confidence interval proposed does not rely on re‐sampling, linearization, variance estimation, design‐effects or joint inclusion probabilities.  相似文献   
105.
Underneath impressive growth levels, the Chilean economy displays signs of being caught in a middle‐income trap. It has been unable to improve its productivity, increase the added value of its exports or upgrade its value chain. Its economy cannot compete either with low‐wage countries or highly productive, innovative countries. Its export strategy based on export promotion seems to have outlived its usefulness. It achieved remarkable quantitative success, but must now attend qualitative attributes. Instead of regarding market‐driven export promotion and state‐led export development as substitutes, this article proposes to view them as alternatives in different stages of development. To choose the appropriate time, more attention should be given to non‐traditional, structural indicators, like export sophistication and political‐institutional capabilities.  相似文献   
106.
Using a recent public expenditure dataset, this article proposes a ‘reality check’ of the level and composition of input subsidies in nine African countries between 2006 and 2013. Results show that input subsidies (1) received close to 35% of agricultural‐specific expenditure on average and (2) cover a variety of interventions, including investments in capital, such as on‐farm irrigation, and in on‐farm services, such as inspection or training. Further, the figures show that input subsidies tended to become entrenched in agricultural budgets over time, leading to sub‐optimal execution rates, and were primarily funded by the national taxpayer, while donors invested more in public goods. Findings confirm that input subsidies crowded out other spending categories likely to be more supportive of long‐term agricultural development objectives. The article concludes that the political economy of input subsidies should be directed to making more concrete efforts to attain a better balance of public expenditure on agriculture. Furthermore, policy‐makers should aim to increase the efficiency and policy coherence of input subsidies, since merely abolishing them is likely to be unfeasible in the short term.  相似文献   
107.
A challenge for large‐scale environmental health investigations such as the National Children's Study (NCS), is characterizing exposures to multiple, co‐occurring chemical agents with varying spatiotemporal concentrations and consequences modulated by biochemical, physiological, behavioral, socioeconomic, and environmental factors. Such investigations can benefit from systematic retrieval, analysis, and integration of diverse extant information on both contaminant patterns and exposure‐relevant factors. This requires development, evaluation, and deployment of informatics methods that support flexible access and analysis of multiattribute data across multiple spatiotemporal scales. A new “Tiered Exposure Ranking” (TiER) framework, developed to support various aspects of risk‐relevant exposure characterization, is described here, with examples demonstrating its application to the NCS. TiER utilizes advances in informatics computational methods, extant database content and availability, and integrative environmental/exposure/biological modeling to support both “discovery‐driven” and “hypothesis‐driven” analyses. “Tier 1” applications focus on “exposomic” pattern recognition for extracting information from multidimensional data sets, whereas second and higher tier applications utilize mechanistic models to develop risk‐relevant exposure metrics for populations and individuals. In this article, “tier 1” applications of TiER explore identification of potentially causative associations among risk factors, for prioritizing further studies, by considering publicly available demographic/socioeconomic, behavioral, and environmental data in relation to two health endpoints (preterm birth and low birth weight). A “tier 2” application develops estimates of pollutant mixture inhalation exposure indices for NCS counties, formulated to support risk characterization for these endpoints. Applications of TiER demonstrate the feasibility of developing risk‐relevant exposure characterizations for pollutants using extant environmental and demographic/socioeconomic data.  相似文献   
108.
We study partial linear single-index models (PLSiMs) when the response and the covariates in the parametric part are measured with additive distortion measurement errors. These distortions are modeled by unknown functions of a commonly observable confounding variable. We use the semiparametric profile least-squares method to estimate the parameters in the PLSiMs based on the residuals obtained from the distorted variables and confounding variable. We also employ the smoothly clipped absolute deviation penalty (SCAD) to select the relevant variables in the PLSiMs. We show that the resulting SCAD estimators are consistent and possess the oracle property. For the non parametric link function, we construct the simultaneous confidence bands and obtain the asymptotic distribution of the maximum absolute deviation between the estimated link function and the true link function. A simulation study is conducted to evaluate the performance of the proposed methods and a real dataset is analyzed for illustration.  相似文献   
109.
Efforts to improve child survival in lower-income countries typically focus on fundamental factors such as economic resources and infrastructure provision, even though research from post-industrial countries confirms that family instability has important health consequences. We tested the association between maternal union instability and children’s mortality risk in Africa, Latin America and the Caribbean, and Asia using children’s actual experience of mortality (discrete-time probit hazard models) as well as their experience of untreated morbidity (probit regression). Children of divorced/separated mothers experience compromised survival chances, but children of mothers who have never been in a union generally do not. Among children of partnered women, those whose mothers have experienced prior union transitions have a higher mortality risk. Targeting children of mothers who have experienced union instability—regardless of current union status—may augment ongoing efforts to reduce childhood mortality, especially in Africa and Latin America where union transitions are common.  相似文献   
110.
Response‐adaptive randomisation (RAR) can considerably improve the chances of a successful treatment outcome for patients in a clinical trial by skewing the allocation probability towards better performing treatments as data accumulates. There is considerable interest in using RAR designs in drug development for rare diseases, where traditional designs are not either feasible or ethically questionable. In this paper, we discuss and address a major criticism levelled at RAR: namely, type I error inflation due to an unknown time trend over the course of the trial. The most common cause of this phenomenon is changes in the characteristics of recruited patients—referred to as patient drift. This is a realistic concern for clinical trials in rare diseases due to their lengthly accrual rate. We compute the type I error inflation as a function of the time trend magnitude to determine in which contexts the problem is most exacerbated. We then assess the ability of different correction methods to preserve type I error in these contexts and their performance in terms of other operating characteristics, including patient benefit and power. We make recommendations as to which correction methods are most suitable in the rare disease context for several RAR rules, differentiating between the 2‐armed and the multi‐armed case. We further propose a RAR design for multi‐armed clinical trials, which is computationally efficient and robust to several time trends considered.  相似文献   
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