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201.
This study examined whether the efficacy of keepin' it REAL, a model program for substance use prevention in schools, was moderated by gender, ethnicity, and acculturation. Gender differences in program efficacy may arise through boys' higher risk of drug use, inadequate attention to girls' developmental issues, or cultural factors like polarized gender expectations. Data came from a randomized trial in 35 Phoenix, Arizona, middle schools involving 4,622 mostly Latino 7th graders. Using multi-level mixed models and multiple imputation missing techniques, results for the total sample showed no gender differences in program effects on recent substance use, but the program was more effective in fostering boys' than girls' anti-drug norms. Subgroup analyses demonstrated several more beneficial program effects for boys than girls (less alcohol and cigarette use and stronger anti-drug norms), but only among less acculturated Latinos. There were no gender differences in program effects among more acculturated Latinos, nor among non-Latino whites.  相似文献   
202.
As canons for trustworthiness developed explicitly in the discourse of qualitative inquiry, the emphasis was on procedural matters rather than fundamentally relational ones. A nod was made to the relational in such strategies as “member checks” but the issues of how the evaluator actually relates to participants and to the larger communities of practice and discourse—matters subsumed under moral principles and ethical standards—were often marginalized. This chapter posits that the first consideration in designing and conducting rigorous evaluation inquiry, and in critiquing the results of any research, should be the study's trustworthiness. Judging a study's trustworthiness, however, should focus on much more than procedural matters; it should also rely on moral principles and ethical standards which specifically address how we relate to an evaluation's participants. Central to these considerations are cross-cultural sensibilities about the nuanced meanings associated with any principles and standards. The chapter provides a theoretical framework for this position and offers two illustrative examples in the form of dialogues.  相似文献   
203.
Despite evidence that individuals with schizophrenia spectrum disorders experience significant and persistent symptoms of anxiety, there are few reports of the use of empirically supported treatments for anxiety in this population. This article describes how we have tried to adapt mindfulness interventions to help individuals with schizophrenia who experience significant anxiety symptoms. Although mindfulness has been widely used to help individuals without psychosis, to our knowledge, this is the first study adapting it to help those with schizophrenia manage worry and stress. We provide an overview of the intervention and use an individual example to describe how our treatment development group responded. We also explore directions for future research of mindfulness interventions for schizophrenia.  相似文献   
204.
Quality of life was compared for lifetime victimized (n = 353) and nonvictimized men (n = 167) for demographic and quality of life variables by a cross-sectional design. The univariate analyses showed that victims compared to nonvictims had a lower quality of life, were younger, more often had upper secondary school education, and were more often blue-collar/low white-collar workers, on student allowances, on unemployment, financially strained, and smokers. The regressions revealed that unemployment, financial strain, smoking, depression, and home/public abuse were associated with reduced quality of life among victimized men. Being a blue-collar/low/intermediate white-collar worker and social support were related to increased quality of life. This study may have provided new insights into the experiences of quality of life of victimized men.  相似文献   
205.
Using a spatially extensive urban database constructed from the Maryland Biological Stream Survey (MBSS), we describe the relationships of nutrients in small-order streams to eight defined categories of percent catchment urbanization, correlations between chloride and conductivity in urban streams, and relationships between nutrients and chloride with two Maryland-specific indices of biotic integrity for benthic macroinvertebrates and fish assemblages. Stream nutrients become elevated with increasing percent catchment urbanization, followed by increases in all four measured nitrogen species and total phosphorus at catchment urbanization levels greater than 10%. There was a strong collinear relationship (r 2 = 0.90) between chloride and conductivity (trimeans) across all eight urbanization classes, where Cl (mg/L) = −0.397 + 0.188*conductivity (μS/cm). Critical values for all water quality parameters with the two Maryland biological indices were derived using quantile regression, with significant regressions developed for 11 of 16 water quality parameters and the two biotic indices. For nitrate (NO3-N), the critical thresholds between fair and poor stream quality for the two Maryland biological indices were 0.83 mg/L (benthic macroinvertebrate assemblages) and 0.86 mg/L (fish assemblages). Increasing stream nutrient and chloride levels, associated with widespread catchment urbanization intensity, now affect many small streams in Maryland, with implications for decreasing water quality in major tributaries and the Chesapeake Bay.  相似文献   
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Deterministic goal programs for employee scheduling decisions attempt to minimize expected operating costs by assigning the ideal number of employees to each feasible schedule. For each period in the planning horizon, managers must first determine the amount of labor that should be scheduled for duty. These requirements are often established with marginal analysis techniques, which use estimates for incremental labor costs and shortage expenses. Typically, each period in the planning horizon is evaluated as an independent epoch. An implicit assumption is that individual employees can be assigned to schedules with as little as a single period of work. If this assumption violates local work rules, the labor requirements parameters for the deterministic goal program may be suboptimal. As we show in this research, this well-known limitation can lead to costly staffing and scheduling errors. We propose an employee scheduling model that overcomes this limitation by integrating the labor requirements and scheduling decisions. Instead of a single, externally determined staffing goal for each period, the model uses a probability distribution for the quantity of labor required. The model is free to choose an appropriate staffing level for each period, eliminating the need for a separate goal-setting procedure. In most cases this results in better, less costly decisions. In addition, the proposed model easily accommodates both linear and nonlinear under- and overstaffing penalties. We use simple examples to demonstrate many of these advantages and to illustrate the key techniques necessary to implement our model. We also assess its performance in a study of more than 1,700 simulated stochastic employee scheduling problems.  相似文献   
210.
The preceding critique [1] of the paper “The Information Problems in Organizations: A Research Model for the Value of Information and Information Systems” [3], reaches general conclusions with respect to the original paper and the applicability of economics to MIS research. These conclusions are based on arguments developed at a different level of analysis than that used in the original paper, and without considering the goals and intent of the original paper. The differences between the critique and the original paper are highlighted.  相似文献   
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