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981.
The relationship between social insurance, which provides families protection against certain risks, and child economic security is understudied. Using the 2004 Survey of Income and Program Participation (SIPP) matched to Social Security Administration benefit records, this article investigates the economic welfare effects of the child component of the US Social Security program. We examine how the poverty rate of child beneficiaries would change, absent Social Security income, and how heavily the family incomes of these children rely on it, by family characteristics. Our findings reveal that Social Security plays an important role in mitigating economic insecurity among children deprived of a wage-earning parent through disability, death, or retirement. Family structure, earnings, and employment status are identified as key factors moderating the effect of Social Security on child recipients’ financial circumstance. 相似文献
982.
Urbanization is a pervasive and growing threat to amphibian populations globally. Although the number of studies is increasing,
many aspects of basic amphibian biology have not been investigated in urban settings. We reviewed 32 urban studies from North
America and quantified the number of species studied and their response to urbanization. We examined existing research on
breeding habitats, life-history stages, movement patterns, and habitat use relative to urbanization. We found amphibians as
a whole respond negatively to urbanization (69 reported responses were negative, 6 were positive and 35 showed no effect).
We caution, however, that many North American species still lack or are associated with conflicting information regarding
species-specific responses (e.g., 89 potential responses were unknown). Approximately 40% of all anuran and 14% of caudate
species in North America were investigated in the literature; however, the most diverse genera (e.g., Plethodon and Eurycea) were the most understudied likely due to their cryptic terrestrial lifestyles and biases in sampling protocols that assess
wetland habitats via call surveys. Research on movement and small scale habitat use was deficient. Adult, juvenile, tadpole,
and egg mass life-history stages commonly served as direct measures of species presence and abundance; however, such data
do not accurately reflect recruitment into subsequent age classes and population persistence. The lack of data on many North
American species may be contributing to poor management of urban amphibian populations and their habitats. 相似文献
983.
984.
985.
In this article we highlight the effects of heterogeneous institutional contexts on transnational professional service firms, a relatively poorly studied issue. Specifically, we provide empirical analysis of how the specificities of the Italian institutional context affect the activities of English legal professional service firms in Milan. This reveals the intimate connection between a variety of capitalism, place specific workplace cultures and practices, and the institution‐related challenges transnational professional service firms and all transnational corporations (TNCs) face. We also reveal the way institutionally generated differences at the level of work practices are managed in transnational law firms through worldwide training programmes designed to ‘govern’ the practices of workers in different parts of the TNC's network. This emphasizes the importance of studying attempts to manage institutional heterogeneity at the level of workplace practices, something often missed in existing mesoscale studies of TNC governance structures. Consequently, we highlight detailed empirical archaeologies that explore the direct links between institutions and practices as an important component of future research on the effects of institutions on TNCs. 相似文献
986.
Differences in infant distress and regulatory behaviors based on the quality of attachment to mother, emotion context (frustration versus fear), and whether or not mothers were actively involved in the emotion-eliciting tasks were examined in a sample of 98 16-month-old infants and their mothers. Dyads participated in the Strange Situation, a limiting task designed to elicit infant frustration, and a novelty task designed to elicit infant fear. Mothers were asked to remain uninvolved during the first minute of each task, and then instructed to engage with their infants as they wished for the remaining three minutes. Independent of concurrent maternal sensitivity, resistant infants were significantly more distressed than secure and avoidant infants. Avoidant infants engaged in fewer active mother-oriented regulation behaviors than secure and resistant infants and engaged in more self-soothing in the mother involved condition than the mother uninvolved condition. Resistant infants engaged in more physical comfort with their mothers and more venting than both secure and avoidant infants, and exhibited a smaller variety of adaptive non-mother-oriented strategies than did secure infants. There were few differences in infant distress and regulatory behaviors as a function of emotion task and maternal involvement. Limitations and implications for future research are discussed. 相似文献
987.
Linguistic stress and sequential statistical cues to word boundaries interact during speech segmentation in infancy. However, little is known about how the different acoustic components of stress constrain statistical learning. The current studies were designed to investigate whether intensity and duration each function independently as cues to initial prominence (trochaic‐based hypothesis) or whether, as predicted by the Iambic‐Trochaic Law (ITL), intensity and duration have characteristic and separable effects on rhythmic grouping (ITL‐based hypothesis) in a statistical learning task. Infants were familiarized with an artificial language (Experiments 1 and 3) or a tone stream (Experiment 2) in which there was an alternation in either intensity or duration. In addition to potential acoustic cues, the familiarization sequences also contained statistical cues to word boundaries. In speech (Experiment 1) and nonspeech (Experiment 2) conditions, 9‐month‐old infants demonstrated discrimination patterns consistent with an ITL‐based hypothesis: intensity signaled initial prominence and duration signaled final prominence. The results of Experiment 3, in which 6.5‐month‐old infants were familiarized with the speech streams from Experiment 1, suggest that there is a developmental change in infants’ willingness to treat increased duration as a cue to word offsets in fluent speech. Infants’ perceptual systems interact with linguistic experience to constrain how infants learn from their auditory environment. 相似文献
988.
Sosulski MR Donnell C Kim WJ 《Journal of social work in disability & rehabilitation》2012,11(1):33-54
Studies indicate positive effects of the U.S. Vocational Rehabilitation Services (VRS) in assisting people with disabilities to find independent employment. Underemployment continues to impact access to adequate health care and other benefits. Workers with disabilities receive fewer benefits, overall. With data from the Longitudinal Study of Vocational Rehabilitation Services Program (LSVRSP), the authors compare the rates of receipt of 6 types of benefits for people with physical, mental, and sensory impairments. Although those with physical disabilities are most likely to receive benefits, all groups lack adequate access to health care, sick leave, and vacation. The authors discuss implications for services provision in the current job market. 相似文献
989.
990.
Walter Bossert Satya R. Chakravarty Conchita D’Ambrosio 《Journal of Economic Inequality》2012,10(2):145-162
We examine the measurement of individual poverty in an intertemporal context. Our aim is to capture the importance of persistence in a state of poverty and we characterize a corresponding individual intertemporal poverty measure. Our first axiom requires that intertemporal poverty is identical to static poverty in the degenerate single-period case. The remaining two properties express decomposability requirements within poverty spells and across spells in order to reflect the persistence issue. In addition, we axiomatize an aggregation procedure to obtain an intertemporal poverty measure for societies and we illustrate our new index with an application to EU countries. 相似文献