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11.
Rushen Shi  Elsa Santos  Jun Gao  Aijun Li 《Infancy》2017,22(6):790-800
This study examined the perception of Mandarin lexical tones by non‐tone‐learning infants. We tested French‐learning 4‐, 8‐, and 11‐month‐olds on Tone 2 (rising) versus Tone 3 (dipping), the most acoustically similar contrast in Mandarin, and on Tone 1 (high) versus Tone 4 (falling), acoustically more dissimilar contrast. We hypothesized that sensitivity should decline with age for the similar contrast, and the dissimilar contrast should remain more discriminable. Infants were habituated to one tone and tested with the same tone versus the contrastive tone. Results showed that the dissimilar T1–T4 contrast was consistently discriminated by all three ages, whereas the discrimination of the similar T2–T3 contrast revealed a tendency to decline over the ages. These results suggest that relative to consonants and vowels, perceptual sensitivity to lexical tones remains stronger in non‐tone‐learning infants. Discrimination of lexical tones is affected by both acoustic salience and perceptual attunement to the native‐language phonology.  相似文献   
12.
Despite recent successes, Brazilian income (cash) transfer policies remain controversial, and alternative approaches to income redistribution are being actively considered. This article contributes to this debate, analysing the effects of several alternative policies for income redistribution in the Brazilian economy using a computable general equilibrium model. Simulations were conducted consistent with the following policies: direct transfer of income, reduction of taxes, and incentives to agricultural exports. The results suggest that transfer of income is the most effective in promoting redistribution of income, with a positive impact on the level of welfare of the poorest households.  相似文献   
13.
Over the last 40 years, the Sahel has seen a long-term downward trend in rainfall. The importance of ecological variables as factors affecting child survival in rural subsistence societies has already been emphasized, but little empirical evidence has been gathered to support this. This paper presents a comparative event history analysis aimed at understanding how rainfall variations may influence child mortality in two neighbouring countries, Burkina Faso and Mali. These countries are similar in terms of population dynamics, economy, livelihood, child mortality and rainfall conditions (i.e. strong south–north decreasing rainfall gradient). Individual data for both countries came from two detailed nationally representative retrospective surveys conducted in 2000. Rainfall data for the 1960–1998 time period were obtained from the Climatic Research Unit. This study shows that child survival in each country is related to specific patterns of rainfall variation across livelihood regions, highlighting the complex nature of environmental causality of child mortality.  相似文献   
14.
有很多模型解释自20世纪60年代以来中国生育率的快速下降,及其在不同地区起始时间的差异。对于引起生育行为变化的最主要因素是有意的政策控制,还是体制变化,抑或是通常的现代化因素,学者们各有争论。在此,我们采用一种行为—体制化的方式将分析从3个不同农村地区收集来的民族志和问卷调查资料。这3个地区包括浙江省的萧山县,河北省磁县,和广东省英德县,它们生育率下降的模式各不相同。我们的分析显示,以上3组因素没有一组能独立解释这3个地方生育率下降的不同开始时间和不同速度。要解释3地生育水平下降的不同模式,我们需要考虑生育率下降早期,包括社会文化环境(如教育的普及,生育控制的意识形态,社会性别关系等)和政治经济体系(如经济发展,计划生育政策,集体劳动体系等)在内的各种地区差异。  相似文献   
15.
This study tested assumptions and conclusions reached in an earlier confirmatory factor analysis (CFA) study of the social competence (SC) construct for preschool children. Two samples (total N = 408; a new Portuguese sample and one from US samples that had participated in the original study) contributed data. Seven SC indicators were tested for mean differences across age, sex, and sample. Significant sex differences were found for peer acceptance (favoring girls) and for initiating affectively neutral interactions (boys had higher rates), and the sex by sample interaction also was significant for initiating interactions (i.e., effect significant only in the Portuguese sample). In CFAs, the hypothesized structure of SC fits the data and was invariant across sample and age within sample in both measurement and structural tests. The model was invariant at the measurement level for sex within sample tests, but not at the structural level. The results replicate and extend understandings of SC reported in the original study.  相似文献   
16.
Interdependency analysis in the context of this article is a process of assessing and managing risks inherent in a system of interconnected entities (e.g., infrastructures or industry sectors). Invoking the principles of input-output (I-O) and decomposition analysis, the article offers a framework for describing how terrorism-induced perturbations can propagate due to interconnectedness. Data published by the Bureau of Economic Analysis Division of the U.S. Department of Commerce is utilized to present applications to serve as test beds for the proposed framework. Specifically, a case study estimating the economic impact of airline demand perturbations to national-level U.S. sectors is made possible using I-O matrices. A ranking of the affected sectors according to their vulnerability to perturbations originating from a primary sector (e.g., air transportation) can serve as important input to risk management. For example, limited resources can be prioritized for the "top-n" sectors that are perceived to suffer the greatest economic losses due to terrorism. In addition, regional decomposition via location quotients enables the analysis of local-level terrorism events. The Regional I-O Multiplier System II (RIMS II) Division of the U.S. Department of Commerce is the agency responsible for releasing the regional multipliers for various geographical resolutions (economic areas, states, and counties). A regional-level case study demonstrates a process of estimating the economic impact of transportation-related scenarios on industry sectors within Economic Area 010 (the New York metropolitan region and vicinities).  相似文献   
17.
The lower extremity performance in elderly female patients with mild to moderate Parkinson's disease (PD; n = 12) and controls (n = 16) was compared. Isometric dynamometry and force-plate measurements were used. PD patients had lower (p < .05) bilateral (BL) maximal isometric leg-extension force (MF), BL isometric MF relative to body mass, and maximal rate of isometric force development than control participants. BL strength deficit was greater (p < .05) in PD patients than in controls. A significantly longer chair-rise time and lower maximal rate of vertical-ground-reaction-force development while rising from a chair was found in PD patients than in controls. These findings suggest that elderly women with PD have lowered voluntary isometric force-generation capacity of the leg-extensor muscles. Reduced BL leg-extension strength might contribute to the difficulty of individuals with PD to rise from a chair.  相似文献   
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19.
This paper investigates the initial planning process for the transition of an organization from a R & D environment to an Operations environment. Using a developed transition life cycle model, the paper demonstrates a four step analysis of the management of the transition. Further, the paper suggests the utilization of existing methods for achieving a smooth transformation under various levels of technical, political, cultural, managerial, and economic uncertainties. Finally, the paper lists possible courses of action and considerations for the transition once the initial planning stage is completed. The concepts herein were used to begin planning the change, from R & D to Operations, of the Space Shuttle Program at NASA.  相似文献   
20.
Intergenerational relations among in-laws are involuntary ties emerging as a consequence of marriage. As such, these relations provide a window through which the dynamics involved in restructuring social networks following life transitions may be observed. A questionnaire, based on the social convoy model, was given to an ethnically diverse sample of adults with living in-laws (N = 170), married 2–15 years. About half of the respondents included in-laws in a concentric circle network diagram of persons close and important to them. The strongest unique predictors of convoy placement for the mother-in-law were support, frequency of contact, relationship quality, and length of marriage, and for the father-in-law were support, relationship quality, and value similarity. This study sheds light on the dynamics of an intergenerational relationship that has been largely ignored in the literature, laying the groundwork for conceptualizing ways to foster positive in-law relationships as a necessary tool in managing the care of the growing numbers of elderly in the new millennium.  相似文献   
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