David B. Thomas

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Artificial neural networks are a key tool for researchers attemptingto understand and replicate the behaviour and intelligencefound in biological neural networks. Software simulations offergreat flexibility and the ability to select which aspects of biologicalnetworks to model, but are slow when operating on more complexbiologically plausible models; while(More)
The future of high-performance computing is likely to rely on the ability to efficiently exploit huge amounts of parallelism. One way of taking advantage of this parallelism is to formulate problems as "embarrassingly parallel" Monte-Carlo simulations, which allow applications to achieve a linear speedup over multiple computational nodes, without requiring(More)
Adenocarcinomas of the esophagus and gastric cardia were once rare. However, for unknown reasons, their incidence has been increasing rapidly over the past 15 years in the United States and parts of Western Europe. In contrast, the incidence of esophageal squamous cell carcinomas has remained relatively constant. To investigate possible reasons for these(More)
BACKGROUND Aggressive challenging behaviour is frequently reported in adults with intellectual disability and it is often treated with antipsychotic drugs. However, no adequate evidence base for this practice exists. We compared flexible doses of haloperidol (a typical, first-generation antipsychotic drug), risperidone (an atypical, second-generation(More)
OBJECTIVE To identify time trends and factors associated with breast-conserving surgery (BCS) and delivery of postoperative radiation therapy among women with stage I or II breast cancer. DESIGN Survey. SETTING Population-based cancer registry in the Seattle-Puget Sound (Wash) region. PARTICIPANTS The study included 8095 women diagnosed with stage I(More)
BACKGROUND Among women who practice breast self-examination (BSE), breast cancers may be detected when they are at an earlier stage and are smaller than in women who do not practice BSE. However, the efficacy of breast self-examination for decreasing breast cancer mortality is unproven. This study was conducted to determine whether an intensive program of(More)
Rapid generation of high quality Gaussian random numbers is a key capability for simulations across a wide range of disciplines. Advances in computing have brought the power to conduct simulations with very large numbers of random numbers and with it, the challenge of meeting increasingly stringent requirements on the quality of Gaussian random number(More)
In many application domains, data are represented using large graphs involving millions of vertices and billions of edges. Graph exploration algorithms, such as breadth-first search (BFS), are largely dominated by memory latency and are challenging to process efficiently. In this paper, we present a reconfigurable hardware methodology for efficient parallel(More)
OBJECTIVE Diabetic kidney disease (DKD) is the single leading cause of kidney failure in the U.S., for which a cure has not yet been found. The aim of our study was to provide an unbiased catalog of gene-expression changes in human diabetic kidney biopsy samples. RESEARCH DESIGN AND METHODS Affymetrix expression arrays were used to identify differentially(More)
One explanation for the relative lack of progress in treating cancer in adolescents and young adults is that the biology of malignant diseases in this age group is different than in younger and older persons, not only in the spectrum of cancers but also within individual cancer types and within the patient (host). Molecular, epidemiological and therapeutic(More)