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941.
This paper studies the behavior of a variety of stakeholders around the adoption of managerial innovations desired by operational managers of health services institutions. We show that if the operational manager may cause the managerial innovation, the tool prospective is subject to power games around coalitions of actors. The study of several management situations in health services institutions enables us, using the game theory, to highlight the “winning”, “losing” and “uncertain” coalitions that can achieve operational management within the establishment to settle a managerial innovation.  相似文献   
942.
943.
In the workload control literature, the Load-Oriented Order Release (LOOR) approach has been neglected since its robustness was questioned at the end of the 1990s. This paper revisits LOOR and evaluates whether its performance can be improved in two ways. First, an intermediate pull release mechanism is added to avoid starvation between periodic release events. This mechanism was recently shown to be effective at improving the performance of a state-of-the-art release method known as LUMS COR. Second, an integer linear programming model is used to manage the trade-off between the timing and load balancing functions of order release. The two refinements are assessed using simulations of different shop configurations, which allow us to evaluate robustness. Results demonstrate that the refinements contribute to improving the performance of LOOR such that it can even outperform LUMS COR. Perhaps counter-intuitively, putting more emphasis on load balancing than on the urgency of individual orders is shown to lead to a lower percentage of tardy orders. Overall, the improvements mean that concerns about LOOR’s robustness are no longer valid – it now appears suitable for a wide range of shops found in practice.  相似文献   
944.
Men's relationships to gender-based violence (GBV) have long been an area of sociological inquiry, but until recently men have primarily been framed as perpetrators of violence against women. More recently, research on men and GBV has broadened to include studying men as victims/survivors, as investigators and law enforcement officers, as passive or active bystanders, and as allies in working to address this social problem. We review this research in an effort to bridge these divergent bodies of work; we identify methodological trends and gaps in existing research, make recommendations for improved theoretical and methodological robustness, and suggest that research perspectives on men and GBV have shifted over time as wider understandings of gender and masculinities become more hopeful and more inclusive. While we see optimism and promise in new directions of GBV research, we urge ongoing research to retain the wisdoms and critical perspectives that marked the beginnings of GBV inquiry.  相似文献   
945.
There is mixed evidence in the existing literature on whether children are associated with greater subjective well-being, with the correlation depending on which countries and populations are considered. We here provide a systematic analysis of this question based on three different datasets: two cross-national and one national panel. We show that the association between children and subjective well-being is positive only in developed countries, and for those who become parents after the age of 30 and who have higher income. We also provide evidence of a positive selection into parenthood, whereby happier individuals are more likely to have children.  相似文献   
946.
Due to economic decline and the recent rise in home foreclosure, many U.S. cities are faced with managing large acreages of vacant land. Interest in local food production on this land has the potential to dramatically reshape the composition of greenspace found within urban landscapes. This study examined how the conversion of vacant land to urban gardens and farms influenced arthropod generalist predator populations and their ability to support biocontrol services. We found that the abundance of Coccinellidae and Syrphidae, and the activity density of Carabidae, Formicidae, and Lycosidae were equivalent among vacant lot and urban garden sites. Dolichopodidae abundance and the activity density of Linyphiidae and Opiliones were reduced in urban gardens whereas Anthocoridae abundance and the activity density of Staphylinidae were greater within urban gardens relative to vacant lots. The biocontrol service supplied by generalist predators was measured using sentinel eggs (Helicoverpa zea (Noctuiidae)) and pupae (Sarcophaga bullata (Sarcophagidae) and Musca domestica (Muscidae)). We found no difference in the biocontrol of H. zea eggs or M. domestica pupae among the focal greenspaces. We found no difference in the removal of S. bullata pupae by predators in June 2010, whereas in August 2010 a greater proportion of pupae were removed in urban garden sites relative to vacant lots. Based on these findings, we discuss the potential of the urban landscape to support generalist predators and sustainable urban gardening and farming.  相似文献   
947.
Aude Bernard 《Demography》2017,54(6):2201-2221
Internal migration intensities fluctuate over time, but both migration levels and trends show great diversity. The dynamics underpinning these trends remain poorly understood because they are analyzed almost exclusively by applying period measures to cross-sectional data. This article proposes 10 cohort measures that can be applied to both prospective and retrospective data to systematically examine long-term trends. To demonstrate their benefits, the proposed measures are applied to retrospective survey data for England that provide residential histories from birth to age 50 for cohorts born between 1918 and 1957. The analysis reveals stable lifetime migration for men but increased lifetime migration for women associated with earlier ages at moving in adulthood and a compression of intervals between consecutive moves. The proposed cohort measures provide a more comprehensive picture of migration behavior and should be used to complement period measures in exploring long-term trends. Increasing availability of retrospective and longitudinal survey data means that researchers can now apply the proposed measures to a wide range of countries.  相似文献   
948.
Coping plays a central role in the appearance and persistence of pathological gambling. Anxious and depressive symptomatology also influence pathological gambling and are related to coping. This study aimed to analyze pathological gamblers’ coping strategies and styles, as well as associated anxious and depressive symptomatology. The study sample included 167 male pathological gamblers (mean age = 39.29 years) and 107 non-gamblers (mean age = 33.43 years). Measures of gambling, coping, and anxious and depressive symptomatology were used. Results showed that pathological gamblers’ scored higher in all the maladaptive coping strategies, problem- and emotion-focused disengagement, and disengagement subscales. These subscales also correlated with pathological gambling, and anxious and depressive symptomatology. Pathological gamblers also scored higher in emotional expression and emotion-focused engagement, with no differences in the rest of the adaptive coping strategies. Coping was also found to predict pathological gambling and anxious and depressive symptomatology. It was found that coping mediated the relationship between pathological gambling and anxious symptomatology when controlling for the effect of age. Specifically, social withdrawal and disengagement stood out as mediators. These results provide practical information for use in clinical settings with people diagnosed with pathological gambling.  相似文献   
949.
950.
Statistical model learning problems are traditionally solved using either heuristic greedy optimization or stochastic simulation, such as Markov chain Monte Carlo or simulated annealing. Recently, there has been an increasing interest in the use of combinatorial search methods, including those based on computational logic. Some of these methods are particularly attractive since they can also be successful in proving the global optimality of solutions, in contrast to stochastic algorithms that only guarantee optimality at the limit. Here we improve and generalize a recently introduced constraint-based method for learning undirected graphical models. The new method combines perfect elimination orderings with various strategies for solution pruning and offers a dramatic improvement both in terms of time and memory complexity. We also show that the method is capable of efficiently handling a more general class of models, called stratified/labeled graphical models, which have an astronomically larger model space.  相似文献   
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