Large scale communication networks—Design and analysis

The paper discusses the problem of design and analysis of large scale communication systems. An iterative process, composed of a minimum cost network design algorithm and a network performance algorithm, is presented for the solution of these problems. Computational considerations, using these algorithms, are discussed.     

Research Note: The LIVITY study: research challenges and strategies for engaging with the black caribbean community in a study of HIV infection

There is an increasing incidence of new HIV‐1 diagnoses among black Caribbeans in the UK, but there has been limited research in this area. The LIVITY study is the first in‐depth epidemiological and behavioural study to examine the impact of HIV among black Caribbeans in the UK. The UK black Caribbean community has traditionally been regarded as less likely to participate in clinical research and surveys. We identified three major challenges to recruitment to the LIVITY study: general distrust of the research process; the considerable stigma surrounding HIV in the black Caribbean community and the sensitivity of obtaining detailed sexual histories. The strategies devised to help overcome these barriers to optimise recruitment included: the establishment of a black Caribbean Community Advisory Group to facilitate communication between the community and the researchers and assist in questionnaire design to improve acceptability to the participants; use of healthcare practitioners as gatekeepers; extensive piloting and modification of the questionnaire among black Caribbean patients; reassurances of confidentiality during recruitment; and ethnic matching between interviewer and study participants. Another challenge was the high rate of loss to follow‐up among eligible patients, potentially compromising the study’s generalisability. Nevertheless, use of the above strategies resulted in a satisfactory enrolment rate of 57%, who were representative of all eligible patients.     

Maternal influences on effortful control in adolescence: Developmental pathways to externalizing behaviors

Adolescents' effortful control is subject to numerous maternal influences. Specifically, a mother's own effortful control is associated with her child's effortful control. However, maternal substance use, psychopathology, and stress within the parenting role may also lead to poor effortful control for their child. Poor effortful control during adolescence can subsequently contribute to a variety of negative outcomes, including externalizing behaviors. A sample of 460 adolescents (47% female, 59.3% Non‐Hispanic Caucasian) was selected from a longitudinal, multigenerational study. The goal was to examine maternal effortful control, substance use, psychopathology, and stress in their offspring's childhood (M_age = 6.27) and their influence on their children's effortful control in early adolescence (M_age = 12.21) and the subsequent effect of effortful control on adolescents’ externalizing behavior (M_age = 13.53). Maternal effortful control (measured via conscientiousness) and psychopathology were associated with adolescent effortful control, which was associated with externalizing behavior a year later. Additionally, there was a significant indirect association between maternal effortful control and adolescent externalizing behaviors via adolescent effortful control. Thus, adolescent effortful control is associated with maternal effortful control but also subject to specific maternal risk factors in childhood. These results inform potential maternal strategies for promoting positive developmental outcomes in adolescents.     

Assessing the effectiveness of strategic planning

This paper describes a method for assessing the effectiveness of strategic planning systems in terms of the results actually observed subsequent to planning activity. The paper explains in particular how, in making the assessment, one might cope with the fact of environmental change subsequent to the setting of planned goals. This ends oriented approach to measuring effectiveness is shown to be complementary to process oriented approaches and is illustrated by an example from the coal industry.     

Improving homeless persons' utilisation of primary care: lessons to be learned from an outreach programme in The Netherlands

Elissen AMJ, Van Raak AJA, Derckx EWCC, Vrijhoef HJM. Improving homeless persons' utilisation of primary care: lessons to be learned from an outreach programme in The Netherlands Faced with rising homelessness, countries around the world are in need of innovative approaches to caring for those without shelter, who, more often than not, suffer from severe health problems. We conducted a case study of an innovative Dutch Primary Care for the Homeless (PCH) programme to gain insight into clients' demographic characteristics, health problems and service use, and to develop an explanation for its success in increasing the latter. Our analyses are based on a combination of quantitative and qualitative data. The results of the study suggest that the success of the PCH programme can be explained by the providers' pragmatism and will to adapt their mode of care provision to the behavioural patterns and needs of their homeless clients.     

Obtaining least absolute value estimates for a two-way classification model

The importance of the two-way classification model is well known, but the standard method of analysis is least squares. Often, the data of the model calls for a more robust estimation technique. This paper demonstrates the equivalence between the problem of obtaining least absolute value estimates for the two-way classification model and a capacitated transportation problem. A special purpose primal algorithm is developed to provide the least absolute value estimates. A computational comparison is made between an implementation of this specialized algorithm and a standard capacitated transportation code.     

USING ARTIFICIAL INTELLIGENCE TECHNIQUES TO ENHANCE THE CAPABILITIES OF MODEL MANAGEMENT SYSTEMS

Decision Support Systems (DSSs) originally were proposed as interactive problem-solving vehicles through which models and analytical techniques could be made available to decision makers. Model management represents a line of research within the DSS field that focuses on the design and implementation of software environments to support the use of DSSs for this purpose. This paper describes the tasks that must be supported within these environments and illustrates how existing prototype Model Management Systems (MMSs) implementations provide this support. The use of artificial intelligence techniques in such implementations are reveiwed, and three scenarios are presented to show how future MMSs could be constructed using these techniques.     

Chiari type I malformations in young adults: implications for the college health practitioner

The authors describe 2 cases of Chiari type I malformation (CM-I) in students presenting to a college health center within a 6-month period. A review of CM-I, including epidemiology, typical presentation, evaluation, and management, is followed by a discussion of the clinical and functional implications of the disorder in an emerging adult population.     

A stratified unrelated question randomized response model

This paper presents a new randomized response model that combines Kim and Warde's (2004) stratified Warner's randomized response technique using optimal allocation with the unrelated question randomized response model. The empirical studies performed show that, for the prior information given, the new model is more efficient in terms of variance (in the case of completely truthful reporting) and mean square error (in the case of less than completely truthful reporting) than its component models.     

Chiari Type I Malformations in Young Adults: Implications for the College Health Practitioner

Abstract

The authors describe 2 cases of Chiari type I malformation (CM-I) in students presenting to a college health center within a 6-month period. A review of CM-I, including epidemiology, typical presentation, evaluation, and management, is followed by a discussion of the clinical and functional implications of the disorder in an emerging adult population.