Agent‐Based Modeling to Simulate Contamination Events and Evaluate Threat Management Strategies in Water Distribution Systems

In the event of contamination of a water distribution system, decisions must be made to mitigate the impact of the contamination and to protect public health. Making threat management decisions while a contaminant spreads through the network is a dynamic and interactive process. Response actions taken by the utility managers and water consumption choices made by the consumers will affect the hydraulics, and thus the spread of the contaminant plume, in the network. A modeling framework that allows the simulation of a contamination event under the effects of actions taken by utility managers and consumers will be a useful tool for the analysis of alternative threat mitigation and management strategies. This article presents a multiagent modeling framework that combines agent‐based, mechanistic, and dynamic methods. Agents select actions based on a set of rules that represent an individual's autonomy, goal‐based desires, and reaction to the environment and the actions of other agents. Consumer behaviors including ingestion, mobility, reduction of water demands, and word‐of‐mouth communication are simulated. Management strategies are evaluated, including opening hydrants to flush the contaminant and broadcasts. As actions taken by consumer agents and utility operators affect demands and flows in the system, the mechanistic model is updated. Management strategies are evaluated based on the exposure of the population to the contaminant. The framework is designed to consider the typical issues involved in water distribution threat management and provides valuable analysis of threat containment strategies for water distribution system contamination events.     

Potential Selective Responding in a Parent Questionnaire Study of Post-Institutionalized Children

This study assesses selective responding in a single wave of data collection and a four-wave study. Participants were 121 parents of post-institutionalized children, identified as “never responders,” “previous responders,” or “wave 4 responders.” Parents evaluated their adopted child's family, school, peer, and behavioral adjustment. Children (47% male) were 2 to 20 years old (M = 10.79, SD = 4.59) and adopted between 5 and 54 months of age (M = 15.49, SD = 9.94). Within a single wave of data collection, no evidence suggested that selective responding contributes much bias. Over a multi-wave study, however, results may under-represent adjustment difficulties.     

Serials spoken here: reports of conferences,institutes, and seminars

Abstract

Reports on the Ohio Valley Group of Technical Services Librarians (OVGTSL) Annual Conference, the April 2004 New England Technical Services Librarians (NETSL) Conference, the 2004 Acquisitions Institute at Timberline Lodge, and the 2004 Conference of the North American Serials Interest Group (NASIG).

Reports are from four conferences held in various parts of the United States and cover a wide range of topics. The Ohio Valley Group of Technical Services Librarians program emphasized the relationship between technical and public services. Education, both formal and continuing, was the theme for the New England Technical Services Librarians. Timberline Lodge hosted another Acquisitions Institute featuring sessions on new discoveries. The report on the 2004 North American Serials Group Annual Conference allows Conference Student Grant Award winner Chris Brady to include some personal reflections along with summaries of the sessions he attended.     

Adolescent Sibling Relationship Quality and Adjustment: Sibling Trustworthiness and Modeling,as Factors Directly and Indirectly Influencing These Associations

The main goal of this study was to examine the direct and moderating effects of trustworthiness and modeling on adolescent siblings' adjustment. Data were collected from 438 families including a mother, a younger sibling in fifth, sixth, or seventh grade (M = 11.6 years), and an older sibling (M = 14.3 years). Respondents completed Web‐based surveys describing sibling conflict and warmth. Siblings reported on trustworthiness and modeling, and mothers described adjustment. Sibling conflict was directly associated with internalizing and externalizing behaviors for both siblings. The older siblings' reports of trustworthiness were directly associated with the outcome measures. The younger siblings' reports of trustworthiness were less directly associated, but a possible salutary effect was most evident under the highest levels of sibling conflict or warmth. Higher sibling modeling was a risk factor for adjustment problems in relations characterized by high conflict. Results support exploring trustworthiness as a key dimension of sibling relations.     

Cost-effectiveness analysis of the New South Wales adult drug court program

In New South Wales, Australia, a cost-effectiveness evaluation was conducted of an adult drug court (ADC) program as an alternative to jail for criminal offenders addicted to illicit drugs. This article describes the program, the cost-effectiveness analysis, and the results. The results of this study reveal that, for the 23-month period of the evaluation, the ADC was as cost-effective as were conventional sanctions in delaying the time to the first offense and more cost-effective in reducing the frequency of offending for those outcome measures selected. Although the evaluation was conducted using the traditional steps of a cost-effectiveness analysis, because of the complexity of the program and data limitations it was not always possible to adhere to textbook procedures. As such, each step involved in undertaking the cost-effectiveness analysis is discussed, highlighting the key issues faced in the evaluation.     

Internet use among community college students: implications in designing healthcare interventions

The Internet has become a commonly used venue for seeking healthcare information. Young adults search the Internet for health information more than any other group, yet little is known about use patterns among community college students. The authors surveyed a diverse community college to assess students' use of the Internet for health-related information. More than 80% had home Internet access, regardless of race or gender. Men and women searched for health information in almost equal numbers. Most students were interested in searching for diet/nutrition topics, and least interested in smoking information. Although the digital divide appears to be closing, varying levels of interest in a variety of important health topics remain. Understanding these differences could guide the design of more effective Web-based health interventions.     

Effects of information on college students' perceptions of antidepressant medication

The authors examined the impact of pharmaceutical companies' advertisements on college students' perceptions of depression and concomitant treatment with antidepressants among 13 male and 31 female undergraduates from a midwestern university. The students were randomly assigned to groups that read either pharmaceutical company advertisements or scientific information about depression and its treatment. The analysis revealed that 40% of the women in the advertisement condition as opposed to 1 woman (6%) in the scientific condition rated themselves as having mild, moderate, or severe depression on the Beck Depression Inventory, second edition. Women in the advertisement condition were significantly more likely to believe that depression required treatment with antidepressant medication and were more willing than women in the scientific condition to suggest antidepressant treatment to others.     

Race and Place in the Adaptation of Mariel Exiles*

The influx of lower class émigrés during the 1980 Mariel Boatlift complicates the “success story” image of previous waves of Cuban exiles to the United States. Examination of Mariel exiles in terms of racial variation in adaptation does not exist; nor is analysis of the geographic distribution and internal migration of Mariel Cubans within the United States represented. Mariel exiles maneuver along distinguishable paths of adaptation as evidenced by patterns of settlement and geographical mobility. I argue that place is a necessary ingredient in illuminating diverse adjustment experiences among immigrants and refugees in the United States.

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