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Jouriles Ernest N.; McDonald Renee; Rosenfield David; Stephens Nanette; Corbitt-Shindler Deborah; Miller Pamela C. 《Canadian Metallurgical Quarterly》2009,77(4):705
This study was a randomized clinical trial of Project Support, an intervention designed to reduce conduct problems among children exposed to intimate partner violence. Participants were 66 families (mothers and children) with at least 1 child exhibiting clinical levels of conduct problems. Families were recruited from domestic violence shelters. The Project Support intervention involves (a) teaching mothers child management skills and (b) providing instrumental and emotional support to mothers. Families were randomly assigned to the Project Support intervention condition or to an existing services comparison condition. They were assessed on 6 occasions over 20 months, following their departure from the shelter. Children in families in the Project Support condition, compared with those in the comparison condition, exhibited greater reductions in conduct problems. Mothers in the Project Support condition, compared with those in the comparison condition, displayed greater reductions in inconsistent and harsh parenting behaviors and psychiatric symptoms. Changes in mothers’ parenting and psychiatric symptoms accounted for a sizable proportion of Project Support’s effects on child conduct problems at the end of treatment. Clinical and policy implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Sandradewi J Prévôt AS Szidat S Perron N Alfarra MR Lanz VA Weingartner E Baltensperger U 《Environmental science & technology》2008,42(9):3316-3323
A source apportionment study was performed for particulate matter in the small village of Roveredo, Switzerland, where more than 70% of the households use wood burning for heating purposes. A two-lane trans-Alpine highway passes through the village and contributes to the total aerosol burden in the area. The village is located in a steep Alpine valley characterized by strong and persistent temperature inversions during winter, especially from December to February. During two winter and one early spring campaigns, a seven-wavelength aethalometer, high volume (HIVOL) samplers, an Aerodyne quadrupole aerosol mass spectrometer (AMS), an optical particle counter (OPC), and a Sunset Laboratory OCEC analyzer were deployed to study the contribution of wood burning and traffic aerosols to particulate matter. A linear regression model of the carbonaceous particulate mass in the submicrometer size range CM(PM1) as a function of aerosol light absorption properties measured by the aethalometer is introduced to estimate the particulate mass from wood burning and traffic (PM(wb), PM(traffic)). This model was calibrated with analyses from the 14C method using HIVOL filter measurements. These results indicate that light absorption exponents of 1.1 for traffic and 1.8-1.9 for wood burning calculated from the light absorption at 470 and 950 nanometers should be used to obtain agreement of the two methods regarding the relative wood burning and traffic emission contributions to CM(PM1) and also to black carbon. The resulting PM(wb) and PM(traffic) values explain 86% of the variance of the CM(PM1) and contribute, on average, 88 and 12% to CM(PM1), respectively. The black carbon is estimated to be 51% due to wood burning and 49% due to traffic emissions. The average organic carbon/total carbon (OC/TC) values were estimated to be 0.52 for traffic and 0.88 for wood burning particulate emissions. 相似文献
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In spite of the obvious impact that decisions on workforce planning have on the capacity of a production system, they are rarely mentioned in strategic capacity planning literature. This paper analyses the implications of embodying decisions on work shifts in strategic capacity planning and proposes a mathematical programming model that allows treating any type of relationship between the intensity in the use of the production equipment and maintenance and variable production costs. A computational experiment shows that the model can be solved in acceptable computing times for moderate values of the number of types of equipment and of work shifts. Using the model, the optimal solutions for diverse scenarios are presented and compared with those obtained under the assumption that the work shifts must be kept invariable over the entire horizon. 相似文献
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Scientometrics - The COVID-19 pandemic is creating a global health emergency. Mapping this health emergency in scientific publications demands multiple approaches to obtain a picture as complete as... 相似文献
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The paper deals with the failure mechanisms and behavior of composite steel-concrete beams prestressed with external tendons and subjected to positive bending. Experimental tests were carried out on beams with straight and draped tendons as well as on a non-prestressed beam. Six simply supported beams subjected to a positive static bending moment were tested up to failure. The influence of shear connection flexibility was taken into account and slip was measured along the beam axis. Concurrently, push-out specimens were made and tested to determine shear force vs. slip curves. It was found that at the same eccentricity of tendons (draped or straight without saddle points) the tendon shape has no significant effect on the behavior and ultimate resistance of composite steel-concrete beams. It is also shown that steel-concrete bond cohesion can significantly influence the behavior of the shear connection in composite beams. This influence is comparable with the design shear resistance of a single stud connector. 相似文献