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11.
This article describes how a frequentist model averaging approach can be used for concentration–QT analyses in the context of thorough QTc studies. Based on simulations, we have concluded that starting from three candidate model families (linear, exponential, and Emax) the model averaging approach leads to treatment effect estimates that are quite robust with respect to the control of the type I error in nearly all simulated scenarios; in particular, with the model averaging approach, the type I error appears less sensitive to model misspecification than the widely used linear model. We noticed also few differences in terms of performance between the model averaging approach and the more classical model selection approach, but we believe that, despite both can be recommended in practice, the model averaging approach can be more appealing because of some deficiencies of model selection approach pointed out in the literature. We think that a model averaging or model selection approach should be systematically considered for conducting concentration–QT analyses. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
12.
The Director General of IOM reflects on the next steps to implement the Global Compact for Migration, IOM's new responsibility as Coordinator of the UN Migration Network, and the role that research can play in realizing the Compact's potential.  相似文献   
13.
The sexual health problems experienced by homeless youth bring into question their use of available sexual health services. Using a qualitative typological analysis, this study aims to identify sexual health services utilization profiles for homeless youth, and to understand the role of the homeless experience on the utilization of sexual health services. Individual interviews were conducted with 33 homeless youth (17 men, 16 women) between 18 and 25?years of age. Typological analysis identified four profiles: (1) a targeted use of sexual health services to determine one’s serological status following a relational change during the homeless experience; (2) a limited use of sexual health services to manage sexual emergencies that arise during the homeless experience; (3) a regular use of sexual health services to avoid the risks associated with the homeless experience; (4) a frequent use of sexual health services to obtain support when engaging in prostitution during the homeless experience. This study shows that the precarious and unstable conditions within the homeless experience incite youth to utilize sexual health services in different ways. These findings point to the importance of rethinking sexual health services to better adapt them to the different utilization profiles of homeless youth.  相似文献   
14.
We introduce and study optimization problems which are related to the well-known Subset Sum problem. In each new problem, a node-weighted digraph is given and one has to select a subset of vertices whose total weight does not exceed a given budget. Some additional constraints called digraph constraints and maximality need to be satisfied. The digraph constraint imposes that a node must belong to the solution if at least one of its predecessors is in the solution. An alternative of this constraint says that a node must belong to the solution if all its predecessors are in the solution. The maximality constraint ensures that no superset of a feasible solution is also feasible. The combination of these constraints provides four problems. We study their complexity and present some approximation results according to the type of input digraph, such as directed acyclic graphs and oriented trees.  相似文献   
15.
Afforestation is inserted in the urban environment and interferes directly in the surface runoff. In order to quantify the rainfall interception by tree species, an experiment was carried out in the city of Uruaçu, Goiás, Brazil, with the four most common tree species in the urban afforestation of the region. The species chosen were the Mangifera indica (mango tree), the Caesalpinia peltophoroides (sibipiruna tree), the Pachira aquatica (munguba tree) and the Licania tomentosa (oiti). In order to register precipitation, ten pluviographs were used. They are capable of measuring precipitation over time in terms of duration, volume, and intensity. For events with a mean cumulative precipitation of 16.7 mm, the mean values of interception found in each species were: Mangifera indica - 8.0 mm; Pachira aquatica - 7.4 mm; Licania tomentosa - 7.2 mm; and Caesalpinia peltophoroides - 4.8 mm. The research confirms the importance of studies related to the identification of the species’ individual characteristics that interfere in the rainfall interception capacity and that can consequently contribute to urban drainage actions. In addition, it proves the existence of variations of rainfall interception in relation to rainfall events and during their occurrences and emphasizes the need for a careful definition of the species that will compose the urban afforestation.  相似文献   
16.
Very preterm (VPT) infants are at risk for altered socio‐emotional stress regulation, even in the absence of perinatal complications. Moreover, becoming a mother of a VPT infant is a traumatic event, which might affect the establishment of a bonding relationship toward the infant during the postnatal period. The main aim of the present study was to assess the association between maternal postnatal bonding and socio‐emotional stress response in 3‐month‐old VPT infants, compared to full‐term (FT) controls. Thirty‐three VPT and 28 FT infant‐mother dyads underwent the maternal Face‐to‐Face Still‐Face (FFSF) procedure to assess socio‐emotional stress regulation. Maternal postnatal bonding was measured through the Maternal Post‐Natal Attachment Scale (MPAS), which includes three scales: Quality of attachment, Absence of hostility, and Pleasure in interaction. The VPT infants exhibited less self‐directed and other‐directed regulatory behaviors during the Still‐Face episode. Mothers of VPT infants reported lower Quality of attachment compared to FT counterparts. Importantly, higher levels of Quality of attachment were associated with more other‐directed behaviors during the Still‐Face episode in FT dyads, whereas this was not observed in VPT dyads. In conclusion, VPT infants might be exposed to a double‐risk condition for socio‐emotional development, encompassing both difficulties in stress response and the exposure to a less‐than‐optimal maternal bonding.  相似文献   
17.
ABSTRACT

In 2013, after nearly two decades of operating in a distributed legacy Integrated Library System (ILS) environment on local servers, the Orbis Cascade Alliance, a consortium of public and private academic libraries in Washington, Oregon, and Idaho, began a two-year-long process to migrate its 37 members to a shared implementation of Ex Libris's cloud-based Alma library management system (LMS) and Primo discovery interface. Although much has been written on electronic resource management (ERM) functionality at an institution level, little has been written on serials and ERM functionality and workflows within a shared consortial environment. This article discusses the challenges and opportunities of implementing a consortial-based LMS, with particular emphasis on serials and ERM functionality. Key migration issues related to serials control, acquisitions, licensing, administration, cataloging, statistics, and interoperability are examined at the institutional and large-scale networked levels. Benefits and limitations of using a shared consortial cloud-based LMS are explored, and the overall capabilities of the Alma LMS for electronic resource management are reviewed.  相似文献   
18.
We derive an empirical poverty index containing most of those proposed in the literature. Then, we study its asymptotic behavior by using empirical processes theory. From the results obtained, we derive a Wald-type test for comparing a vector of theoretical poverty indices to a vector of reference indices. We study the test statistic under the null hypothesis of equality, fixed alternatives, and a sequence of local alternatives. A simulation experiment conducted shows that our test performs well for exponential and Pareto data.  相似文献   
19.
The way public policies are managed in Brazil has changed since the 1988 Federal Constitution. This study aimed to identify how changes in the structure of public expenditure composition at Brazilian federal states influenced local human development in these states. The states’ public expenditures were categorized according to their nature as spending indices whereas human development was measured through a human development index (HD). To verify the relationships between these variables, an accounting-social theoretical model was created and estimated through latent growth modeling (LGM). The LGM measurement period comprised five administration cycles of the Brazilian states (1988–2011). Variables were measured on data of the second year of state government term; their mean initial values and growth rates were recorded. Results show that, influenced by policies of centralized regulation promoted by the federal government, only the social spending growth rates had statistically significant effect on the human development growth rate, although not considered of great magnitude. Among mean initial values, the most significant was that of minimum spending (SIm), which denotes the direct impact of the Fiscal Accountability Law [Lei de Responsabilidade Fiscal, in Portuguese] on human development improvements. The mean initial value of economic spending also showed a positive and significant effect on HD growth rate.  相似文献   
20.
This article focuses on English language teaching in Brazilian public schools, based on experiences in primary and secondary education, as well as in Teaching Practicum courses at a university. Through these experiences, the article critiques the overemphasis on grammar and the lack of an intercultural approach. The author engages the reader with a theoretical discussion regarding the connection between language and culture and the possibilities for the implementation of intercultural principles. The article closes with some reflections on what intercultural language learning looks like in practice.  相似文献   
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