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11.
This paper presents a qualitative analysis of front‐line practices regarding emergency removals in Finnish and Irish child protection. It examines how the responses to children's immediate danger are framed by legislation and how front‐line practitioners assess the child's situation and make emergency placement decisions. The data consist of interviews with 16 Irish and 33 Finnish social workers. These child welfare protection systems respond differently to a task that appears to be similar. The Irish team‐based practice rests on the social workers' shared assessment of the child's needs, and the formal decision is made by the courts (or police officers at night‐time); and the Finnish practice involves only one single social worker who makes both the assessment and the removal decision. The Irish system is tightly time regulated, whereas the Finnish system provides a more flexible time frame. Both approaches put a lot of stress on social workers' practice, which also includes creative workarounds (e.g., “planned emergency removals” in Finland). Future research will need to explore these features from the point of view of a child's right to protection.  相似文献   
12.
In this study, the authors used data from the first wave of the Generations and Gender Survey to investigate relationship quality among currently married and cohabiting individuals ages 18 to 55 (N = 41,760) in 8 European countries (Bulgaria, France, Germany, Hungary, Norway, Romania, Russia, and The Netherlands). They expected to find fewer differences between cohabitation and marriage in countries where cohabitation is widespread. Controlling for a range of selection characteristics of respondents and their partners (e.g., common children, union duration, and education), the analyses showed that in all countries cohabiters more often had breakup plans and were less satisfied with their relationships than individuals who married. This cohabitation gap in relationship quality was largest in Russia, Romania, and Germany, which indeed were among the countries in the current sample where cohabitation was least prevalent.  相似文献   
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Physical activity takes place in different social contexts such as leisure, home, and work. However, the differential associations of these distinct categories of activity with aspects of well-being have rarely been investigated. This study was designed to estimate independent associations of (a) leisure-time, (b) domestic and (c) work-related physical activities with subjective well-being in older adults. A cross-sectional survey was conducted in 2009 with 2,295 community-dwelling older adults aged 65 or older in Kaohsiung, Taiwan. Among them, 307 participants were selected for a 3-year follow-up study in 2012. The results based on cross-sectional and longitudinal analyses demonstrated that leisure-time physical activity, after multivariate adjustment, was positively associated with five dimensions of well-being, including ‘physical’, ‘psychological’, ‘independence’, ‘learning and growth’, and ‘social’ well-being. Household physical activity was positively associated only with ‘social’ well-being. Occupational physical activity was not related to any dimension of well-being. The study suggests that associations between physical activity and dimensions of subjective well-being during later life are dependent on the social context in which the activity takes place. This study indicates that physical activity taken as leisure has greatest potential to enhance the quality of life of older adults.  相似文献   
15.
Asymptotics of an alternative extreme-value estimator for the autocorrelation parameter in a first-order bifurcating autoregressive (BAR) process with non-gaussian innovations are derived. This contrasts with traditional estimators whose asymptotic behavior depends on the central part of the innovation distribution. Within any BAR model, the main concern is addressing the complex dependency between generations. The inability of traditional methods to handle this dependency motivated an alternative procedure. With the combination of an extreme-value approach and a clever blocking argument, the dependency issue within the BAR process was resolved, which in turn allowed us to derive the limiting distribution for the proposed estimator through the use of regular variation and non-stationary point processes. Finally, the implications of our extreme-value approach are discussed with an extensive simulation study that not only assesses the reliability of our proposed estimate but also presents the findings for a new estimator of an unknown location parameter θ and its implications.  相似文献   
16.

Age‐specific models of population renewal (with and without feedback) which imply convergence to a stable state for some levels of fertility or feedback may imply the presence of long‐term cycling around a constant or exponentially changing equilibrium for other levels of fertility or feedback. The switch from one regime to the other is a “bifurcation.”; The conditions for bifurcation involve the roots of an analogue of Lotka's Equation.

Typically bifurcation is induced by raising the strength of feedback or the level of fertility. It has been known since the early 1980s, however, that this is sometimes impossible. It is sometimes impossible even with the linear renewal equation itself and with the most basic of non‐linear models, Lee's cohort feedback model.

Here it is proved that this typical route to bifurcation does not fail for these basic models in the presence of a condition which always holds for realistic applications with higher organisms: the existence of a span of ages before the onset of fertility.

Specifically, a strictly positive lower bound on ages of procreation is proved to be sufficient to guarantee the existence of a rescaling of Lotka's Equation for which the real part of some complex root vanishes. This result holds for absolutely Lebesgue‐integrable (signed) net maternity functions on the positive real line and for absolutely summable (signed) net maternities on the positive integers.

It follows that Coale's rescaling device for the analysis of approach to stability in stable population theory can be implemented for all realistic human net maternity schedules. It also follows that the many special cases of the cohort feedback model throughout population biology will all generate persistent cycling instead of stability if feedback is sufficiently strong.  相似文献   
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Abstract

This research develops a model of relationships among components of Total-JIT, including JIT-information, JIT-manufacturing, JIT-purchasing, and JIT-selling, to establish an implementation hierarchy based on relative importance. The data collected relates to the relationships among JIT components and two performance measures, supply chain competency and organizational performance. Two groups are used in the research, one group of five operations management academics and another group of 30 practicing operations managers working in U.S. manufacturing firms. An interpretive structural modelling methodology is used to develop alternative structural models. The academics’ data show JIT-information emerging as lynchpin of relationships, directly impacting all other JIT practices and both performance measures. The practitioners’ data indicates that all JIT practices and performance measures are interactive as components and outcomes. This study is the first to apply interpretive structural modelling to investigate the interplay among total-JIT components and the performance measures of supply chain competency and organizational performance.  相似文献   
20.
Consistent with a new genre of research on life-course analyses of health-service use, this study explores the consequences of long-term exposure to a risk factor. Drawing from cumulative-disadvantage theory, the study examines whether obesity, especially chronic obesity, increases hospitalization admission and length of stay. Analyses make use of hospital records abstracted over 20 years from a national survey of adults 41 to 77 years of age at baseline (n = 4,574). Multiple measures of body weight are used to calculate adult obesity duration. Results reveal that obesity increased hospital admissions and length of stay over the 20 years studied. Among persons obese at any time during the study, years of obesity also led to longer stays. The findings highlight the utility of measures of the duration of risk exposure for both life-course studies of health and tests of cumulative-disadvantage theory.  相似文献   
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