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21.
This study examines whether place of residence is a factor associated with reporting a positive HIV/AIDS, Hepatitis C (HCV), or Sexually Transmitted Disease (STD) status in a sample of 400 injection drug users (IDUs) residing on the Island of Puerto Rico (N=139) and in western Massachusetts (N=261). Logistic regression models revealed that IDUs residing in western Massachusetts were 66% less likely to be HIV positive compared to IDUs residing in Puerto Rico (p<.000) while IDUs residing in western Massachusetts were about 67% less likely to have a positive STD status than those residing in Puerto Rico (p<.000). Place of residence was not significantly associated with HCV status. Results indicate the need to develop prevention programs tailored to the unique socio-cultural context of Puerto Rican IDUs residing on the Island of Puerto Rico whose circumstances differ from those in the mainland US. To reduce drug use, HIV/AIDS, HCV, and STDs among Puerto Ricans in both locales, the Capacity Enhancement Model is proposed in order to develop more effective prevention programs.  相似文献   
22.
2003年8月的一个下午,包括百老汇在内的美国东北部、中西部城市以及加拿大安大略省经历了一次大停电,约5千万人受到这次停电事故的影响。除了抱怨不方便、公交乘客一筹莫展、以及饭店和市场里的食品腐败变质之外,许多城市居民感到震撼的是,当夜幕降临时,透过黑暗的摩天大楼,人们凝望天空,看到了令人惊讶的景象——璀璨星空。这些居住在东北部电力发达城市的居民自发聚集,凝望星空这一幕被《纽约时报》报道。  相似文献   
23.
This study aims to analyze the factors that justify the low use of a mechanical transfer in the context of a long-term institution. It is a device intended for internal transportation of individuals who have mobility problems. The analysis involves researchers from the fields of health and engineering in order to generate design criteria that consider the needs of caregivers and patients of this institution. To understand the reality of this site and their specificities, was used Ergonomic Work Analysis.  相似文献   
24.
This project, developed by the Design Studies Research Group at the Universidad Pontificia Bolivariana (UPB), presents a design proposal focused on human factors for ischial support for the stations of the Medellín Metro. An initial pilot scheme was developed on Platform 'A' of San Antonio - the most important transfer station. The methodology of the Ergonomics Research Division at UPB constituted the basis of the project. This methodology observes, analyses and draws conclusions of the conditions that optimize the User-Product-Context nexus, and in doing so defines design requirements which, in this proposal, centered on the needs of the users of the Medellín Metro. The Experimental Morphology Research Division provided technical support in the form of modelling, production and structural testing of the object. The proposal includes thematic units, themes and priority components for analysis and application in the design process. In addition, the project generates certain activities and moments that future designers can develop in a parallel manner, coherent with the vision of ergonomics. The methodology focused on the requirements of the users and took into account the existing space (the Metro System), thus establishing relationships of use that were coherent with the principles of ergonomics and design.  相似文献   
25.
This work presents the initial steps of ergonomic analysis of industrial activities, which are being held in the premises of an Agricultural Experimental farm belonging to an institution of higher education. The methods employed in the initial step was confined to desk research, its purpose was to know the demographic profile and understand organizational structure followed by systematic observations in workplaces using semi-structured interviews and a questionnaire of perception to operators. The presentation of the results will provide a summary of the analysis of activity sectors visited, understanding the biomechanical efforts entered (posture and strength), as well as the evaluation according to the perception of officials to respect the constraints, ambience and suggestions. It was noted that 90% of employees surveyed feel some kind of discomfort. It also highlights the age factor of this questionnaire, in which the majority (90%) is above 40 years old, and this fact confirms and reinforces the appearance or accumulation of injuries among the employers. At this stage there was no intention to deploy improvements, but create assumptions and guide future intervention actions that can be performed.  相似文献   
26.
Interval censoring appears when the event of interest is only known to have occurred within a random time interval. Estimation and hypothesis testing procedures for interval-censored data are surveyed. We distinguish between frequentist and Bayesian approaches. Computational aspects for every proposed method are described and solutions with S-Plus, whenever are feasible, are mentioned. Three real data sets are analyzed.  相似文献   
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28.
This study determined the shape of trajectories from ages 13 to 19 of 4 types of dating abuse perpetration and examined whether the demographic characteristics of sex, minority status, socioeconomic status, and family structure systematically explained variation in the trajectories. The data are from 5 waves of data collected from 973 adolescents participating in the control group of a randomized trial. The mean trajectory for psychological dating abuse was positive linear, but the mean trajectories were curvilinear for moderate physical, severe physical, and sexual dating abuse. At all ages, boys reported more severe physical and sexual dating abuse than girls, minorities reported more moderate and severe physical dating abuse than Whites, adolescents in single‐parent households reported more psychological and severe physical dating abuse than those in 2‐parent‐households, and parental education was negatively associated with psychological and moderate physical dating abuse perpetration. The findings have implications for future research and for practice.  相似文献   
29.
Identifying which factors affect firms' performance is a critical issue in strategic management research. This paper addresses the influence of managerial team over the behaviour and performance of small and medium‐sized enterprises (SMEs). By treating top management team (TMT) characteristics as predictors of a firm's strategic orientation, we seek to provide a more complete understanding of how the characteristics of managerial teams shape decision‐making processes and SMEs' behaviours in order to successfully compete in low munificent environments. Based on primary data regarding managerial characteristics and firms' behaviours of a sample of 295 SMEs, our results confirm that a firm's strategic orientation plays a mediating role in explaining how TMT characteristics determine SMEs' performance.  相似文献   
30.
A graph \(G\) with convex-\(QP\) stability number (or simply a convex-\(QP\) graph) is a graph for which the stability number is equal to the optimal value of a convex quadratic program, say \(P(G)\). There are polynomial-time procedures to recognize convex-\(QP\) graphs, except when the graph \(G\) is adverse or contains an adverse subgraph (that is, a non complete graph, without isolated vertices, such that the least eigenvalue of its adjacency matrix and the optimal value of \(P(G)\) are both integer and none of them changes when the neighborhood of any vertex of \(G\) is deleted). In this paper, from a characterization of convex-\(QP\) graphs based on star sets associated to the least eigenvalue of its adjacency matrix, a simplex-like algorithm for the recognition of convex-\(QP\) adverse graphs is introduced.  相似文献   
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