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381.
ABSTRACT

Caring for dependents with disabilities and how this type of care differs from the care of typically developing dependents has largely remained unaddressed in the work–family literature, partly because of a lack of theoretical development on the concept of dependent family care. Studies examining dependent family care often apply a life course perspective, missing key disability factors influencing dependent family care demands and need for resources. This article develops a theoretical framework of dependent family care that accounts for both typical care, which follows the life course trajectory, and exceptional care, which follows a disability trajectory. We position dependent family care as based on a continuum, achieved by adapting life course theory, family adjustment to chronic illness, ecological systems theory, stigma theory and the social model of disability into a model. We explain how dependent family care occurs and what contributes to whether one is engaging in typical or exceptional care. We draw broad constructs representing predictors of different types of dependent family care. We provide specific examples to illustrate how one might test theoretical propositions, an agenda for further research and discuss implications for family–work–community research and practice.  相似文献   
382.
The ability to discriminate the trajectories of moving objects is highly adaptive and fundamental for physical and social interactions. Therefore, we could reasonably expect sensitivity to different trajectories already at birth, as a precursor of later communicative and defensive abilities. To investigate this possibility, we measured newborns' looking behavior to evaluate their ability to discriminate between visual stimuli depicting motion along different trajectories happening within the space surrounding their body. Differently from previous studies, we did not take into account defensive reactions, which may not be elicited by impending collision as newborns might not categorize approaching stimuli as possible dangers. In two experiments, we showed that newborns display a spontaneous visual preference for trajectories directed toward their body. We found this visual preference when visual stimuli depicted motion in opposite directions (approaching vs. receding) as well as when they both moved toward the peripersonal space and differed only in their specific target (i.e., the body vs. the space around it). These findings suggest that at birth human infants seem to be already equipped with visual mechanisms predisposing them to perceive their presence in the environment and to adaptively focus their attention on the peripersonal space and their bodily self.  相似文献   
383.
384.
Burns and Stalker's theory of organic/mechanistic structures (1961, The Management of Innovation. London: Tavistock) has been widely used. However, review of the empirical literature revealed inconsistencies in how the concepts have been operationalized. These inconsistencies may interfere with the ability to consolidate knowledge. This paper reviews the various ways in which researchers have operationalized the concepts, and summarizes the empirical findings derived from these operationalizations. In doing so, it highlights gaps and opportunities for future empirical and methodological work, suggesting the need to further our theoretical conceptualization of the concepts and to draw attention to Burns and Stalker's ( 1961 ) largely neglected corollary of the employee experience. As such, this review provides a road map for future exploration of the wide‐ranging implications associated with organic and mechanistic structures.  相似文献   
385.
386.
Aging males have a decrease in testosterone levels, by which the testosterone treatment may influence in a negatively fashion the liver.

Aim: This study aimed to analyze the effects of aging with or without testosterone administration on the liver components of animals.

Methods: Wistar rats were divided into three groups: 20 months’ group (G20), 24 months’ group (G24), group treated with testosterone for 16 weeks (GT). All groups were sacrificed at 24 months except for G20 that was sacrificed at 20 months.

Results: Aging and testosterone treatment alters the body weight (BW), liver weight (LW) and relative liver weight. Besides, testosterone increased the mitogen capacity of hepatocytes. Nonetheless, we reinforce the negative effects of testosterone on old animals’ liver as chronic hepatic congestion and/or cholestasis. In addition, we observed that testosterone plays an important role on hepatic glycogen stores.

Conclusions: Our study showed many implications for the knowledge about the effects of aging with or without testosterone administration on old animals’ liver.  相似文献   

387.
This paper addresses the issue of estimating the expectation of a real-valued random variable of the form \(X = g(\mathbf {U})\) where g is a deterministic function and \(\mathbf {U}\) can be a random finite- or infinite-dimensional vector. Using recent results on rare event simulation, we propose a unified framework for dealing with both probability and mean estimation for such random variables, i.e. linking algorithms such as Tootsie Pop Algorithm or Last Particle Algorithm with nested sampling. Especially, it extends nested sampling as follows: first the random variable X does not need to be bounded any more: it gives the principle of an ideal estimator with an infinite number of terms that is unbiased and always better than a classical Monte Carlo estimator—in particular it has a finite variance as soon as there exists \(k \in \mathbb {R}> 1\) such that \({\text {E}}\left[ X^k \right] < \infty \). Moreover we address the issue of nested sampling termination and show that a random truncation of the sum can preserve unbiasedness while increasing the variance only by a factor up to 2 compared to the ideal case. We also build an unbiased estimator with fixed computational budget which supports a Central Limit Theorem and discuss parallel implementation of nested sampling, which can dramatically reduce its running time. Finally we extensively study the case where X is heavy-tailed.  相似文献   
388.
The relationship between migration and child health in individual countries is well known, but the cross-national variation in this relationship is largely untested. Using Demographic and Health Survey (DHS) data from 52 medium and low income countries, this study examines the effect of rural–urban migration on infant mortality and whether its effect varies cross-nationally. A secondary objective is to determine whether there is a relationship between the time a child is born in the migration process and infant mortality. Hypotheses are developed on the basis of competing theories on the relationship between migration and health. There are modest, but significant cross-national effects of rural–urban migration on infant mortality, which were better revealed in the presence of family- and child-level variables. The results also show that the unadjusted effects of rural–urban migration are quite substantial, but were largely accounted for by family- and child-level factors including education, socioeconomic status (SES), marital status, birth order, maternal age at child’s birth, and inter-births intervals. The results largely point to a selection process, which is further confirmed by results showing that the hazards of infant death increase with length of urban residence. Programs that target increasing maternal education, improving household SES, and lengthening interbirth intervals would therefore greatly benefit child survival in less developed countries.  相似文献   
389.
Whether homosexuality or internalized homo-negativity is the critical variable affecting the mental health of men who have sex with men has long been debated. As part of a larger study, 422 Midwestern homosexual men completed questionnaires examining degree of homosexuality, internalized homo-negativity, and depression. Logistic regression modeling identified internalized homo-negativity, but not degree of homosexuality, as significantly associated with greater adjustment depression (OR = 1.5), major depression (OR = 2.6), dysthymia (OR = 1.5), and likelihood of being in therapy (OR = 1.4). Internalized homo-negativity was also negatively associated with overall sexual health, psychosexual maturation, comfort with sexual orientation, "outness," and peer socialization. Internalized homo-negativity, not homosexuality, appears associated with negative health outcomes. Providers should promote sexual health and avoid interventions that reinforce internalized homo-negativity.  相似文献   
390.
In this paper we analyse how whistle-blowing affects fraudulent behaviour of managers while the company instigates imperfect internal audit to detect the fraud. To do so, we employ in a first step a non-cooperative inspection game to analyse fraudulent behaviour of a manager controlled by an internal auditor. In a second step we introduce exogenous whistle-blowing of a manager’s employee to aid the auditor to reveal the fraud. In a third step, the two-person inspection game is extended to a three-person approach with endogenous whistle-blowing. Our novel results are that the intensity of internal audit is always lower with whistle-blowing than without and that whistle-blowing renders the manager to act less fraudulently than compared to the basic inspection game if and only if she is unaware of the whistle-blower’s expected pay-off and the efficacy of internal audit is sufficiently low.  相似文献   
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