Discovering classes in microarray data using island counts

We present a new biclustering algorithm to simultaneously discover tissue classes and identify a set of genes that well-characterize these classes from DNA microarray data sets. We employ a combinatorial optimization approach where the object is to simultaneously identify an interesting set of genes and a partition of the array samples that optimizes a certain score based on a novel color island statistic. While this optimization problem is NP-complete in general, we are effectively able to solve problems of interest to optimality using a branch-and-bound algorithm. We have tested the algorithm on a 30 sample Cutaneous T-cell Lymphoma data set; it was able to almost perfectly discriminate short-term survivors from long-term survivors and normal controls. Another useful feature of our method is that can easily handle missing expression data.     

Consumption Over the Life Cycle

This paper estimates a structural model of optimal life‐cycle consumption expenditures in the presence of realistic labor income uncertainty. We employ synthetic cohort techniques and Consumer Expenditure Survey data to construct average age‐profiles of consumption and income over the working lives of typical households across different education and occupation groups. The model fits the profiles quite well. In addition to providing reasonable estimates of the discount rate and risk aversion, we find that consumer behavior changes strikingly over the life cycle. Young consumers behave as buffer‐stock agents. Around age 40, the typical household starts accumulating liquid assets for retirement and its behavior mimics more closely that of a certainty equivalent consumer. Our methodology provides a natural decomposition of saving and wealth into its precautionary and life‐cycle components.     

Reliability Analysis for Hazardous Waste Treatment Processes

The reliability of a treatment process is addressed in terms of achieving a regulatory effluent concentration standard and the design safety factors associated with the treatment process. This methodology was then applied to two aqueous hazardous waste treatment processes: packed tower aeration and activated sludge (aerobic) biological treatment. The designs achieving 95 percent reliability were compared with those designs based on conventional practice to determine their patterns of conservatism. Scoping-level treatment costs were also related to reliability levels for these treatment processes. The results indicate that the reliability levels for the physical/chemical treatment process (packed tower aeration) based on the deterministic safety factors range from 80 percent to over 99 percent, whereas those for the biological treatment process range from near 0 percent to over 99 percent, depending on the compound evaluated. Increases in reliability per unit increase in treatment costs are most pronounced at lower reliability levels (less than about 80 percent) than at the higher reliability levels (greater than 90 percent, indicating a point of diminishing returns. Additional research focused on process parameters that presently contain large uncertainties may reduce those uncertainties, with attending increases in the reliability levels of the treatment processes.     

The Dynamics of Disaster Recovery: Resilience and Entropy in Hurricane Response Systems 2005–2008

The challenge for policy makers and disaster managers is to achieve a balance between two dynamics — resilience and entropy — in order to develop sustainable risk reduction. Achieving an appropriate balance between resilience and entropy in any given community requires a systematic exploration of both dynamics. The recent hurricanes that struck Louisiana, Hurricane Katrina on August 29, 2005 and Hurricane Gustav, on September 1, 2008, offer an unusual opportunity to assess the degree to which both dynamics operated following Hurricane Katrina.     

Patterns of Autonomic Arousal in Imaginal Situations of Winning and Losing in Problem Gambling

AIMS: To examine changes in skin conductance level (SCL), for problem gamblers in response to personally relevant imaginal tasks, representing winning or losing. SETTING, DESIGN, PARTICIPANTS AND MEASUREMENTS: SCL and subjective arousal were compared for problem poker machine gamblers (n = 13) and a control group (n = 20). Participants were asked to describe a situation in which they had (a) won and (b) lost during a period of gambling. Before and during the task, recordings of SCL were taken. FINDINGS: There were significant differences between responses of problem and social gamblers. A significant interaction indicated that social gamblers became more aroused in reaction to winning than losing, whereas problem gamblers became equally aroused in response to both tasks. CONCLUSIONS: The results suggest that it may be responses to losing, rather than winning that are paramount to the development and maintenance of problem gambling.     

Many a slip between cup and lip. Process evaluation of a program to promote and support evidence-based public health practice

The main aims of this study are to document whether an intervention for promoting evidence-based public health practice had been delivered as intended and to explore the reasons for its lack of impact. Process data from the implementation of the program and data from interviews with 40 public health physicians are analyzed. Although they expressed satisfaction with the service, the doctors experienced the program as rather irrelevant for their daily work. They did not perceive that they dealt with many issues relevant for the use of research information, and if they did, referring to research would not make any difference to the way others perceived their advice. There is a need to develop more overlying strategies for integrating evidence into decision making than addressing the individual level.     

A survey of problematic sexualized behaviors of children in the New York City Child Welfare System:estimates of problem, impact on services, and need for training

Forty-eight of 52 (92%) agencies contracted with the New York City Administration for Children's Services (ACS) responded to a survey about problematic sexualized behaviors (PSB) of children in different levels of care within the child welfare system. Results revealed that almost all agencies reported PSB within their foster boarding home and residential treatment centers. A majority of agencies perceived PSB to be a significant problem for which staff and families were not sufficiently trained. These findings highlight many avenues for advocacy, clinical intervention, and staff development.