Statistical Modeling and Inference for Genomics: Data Integration, Shrinkage and Network Reconstruction

Vaart, A.W. van der [Promotor]Wiel, M.A. van de [Promotor

Detection and direction-discrimination of diotic and dichotic ramp modulations in amplitude and phase

When the source of a tone moves with respect to a listener's ears, dichotic (or interaural) phase and amplitude modulations (PM and AM) are produced. Two experiments investigated the psychophysical characteristics of dichotic linear ramp modulations in phase and amplitude, and compared them with the psychophysics of diotic PM and AM. In experiment 1, subjects were substantially more sensitive to dichotic PM than diotic PM, but AM sensitivity was equivalent in the dichotic and diotic conditions. Thresholds for discriminating modulation direction were smaller than detection thresholds for dichotic AM, and both diotic AM and PM. Dichotic PM discrimination thresholds were similar to detection thresholds. In experiment 2, the effects of ramp duration were examined. Sensitivity to dichotic AM and PM, and diotic AM increased as duration was increased from 20 ms to 200 ms. The functions relating sensitivity to ramp duration differed across the stimuli; sensitivity to dichotic PM increased more rapidly than sensitivity to dichotic or diotic AM. This was also reflected in shorter time-constants and minimum integration times for dichotic PM detection. These findings support the hypothesis that the analysis of dichotic PM and AM rely on separate mechanisms. © 2003 Acoustical Society of America

Successful long-term weight loss among participants with diabetes receiving an intervention promoting an adapted Mediterranean-style dietary pattern: The Heart Healthy Lenoir Project

Objective: To examine weight change by diabetes status among participants receiving a Mediterraneanstyle diet, physical activity, and weight loss intervention adapted for delivery in the southeastern USA, where rates of cardiovascular disease (CVD) are disproportionately high. Research design and methods: The intervention included: Phase I (months 1-6), an individually tailored intervention promoting a Mediterranean-style dietary pattern and increased walking; Phase II (months 7-12), option of a 16-week weight loss intervention for those with BMI≥25 kg/m2 offered as 16 weekly group sessions or 5 group sessions and 10 phone calls, or a lifestyle maintenance intervention; and Phase III (months 13-24), weight loss maintenance intervention for those losing ≥8 pounds with all others receiving a lifestyle maintenance intervention. Weight change was assessed at 6, 12, and 24-month follow-up. Results: Baseline characteristics (n=339): mean age 56, 77% female, 65% African-American, 124 (37%) with diabetes; mean weight 103 kg for those with diabetes and 95 kg for those without. Among participants with diabetes, average weight change was -1.2 kg (95% CI -2.1 to -0.4) at 6 months (n=92), -1.5 kg (95% CI -2.9 to -0.2) at 12 months (n=96), and -3.7 kg (95% CI -5.2 to -2.1) at 24 months (n=93). Among those without diabetes, weight change was -0.4 kg (95% CI -1.4 to 0.6) at 24 months (n=154). Conclusions: Participants with diabetes experienced sustained weight loss at 24-month follow-up. High-risk US populations with diabetes may experience clinically important weight loss from this type of lifestyle intervention

L'homme et l'eau dans le bassin du lac Tchad = Man and water in the lake Chad basin

That the notorious Sahelian drought (1968-1973) of Sahelo-Sudan Sub-Sahara was not unique has been established as a chronological sequence of past droughts in the Lake Chad basin. Historical drought chronology is traceable to written evidence. Pre-historical evidence of dune landscapes in the Nigerian Lake Chad basin may be located on the ground or in satellite imagery. Nevertheless, the 1980s drought continuum has the characteristic of being unique in the context of its severity and longevity. Some possible forcing agencies are considered as being meterological, while anthropogenetically-induced drought-desiccation is also of concern. Recently it has been indicated that a linkage between sea-surface temperatures and sahelian droughts seems to be of significance. (Résumé d'auteur

Local minimal realisations of trained Hopfield networks

A methodology for investigating the invariant structural characteristics..

PLRS: a flexible tool for the joint analysis of DNA copy number and mRNA expression data

DNA copy number and mRNA expression are commonly used data types in cancer studies. Available software for integrative analysis arbitrarily fixes the parametric form of the association between the two molecular levels and hence offers no opportunities for modelling it. We present a new tool for flexible modelling of this association. PLRS uses a wide class of interpretable models including popular ones and incorporates prior biological knowledge. It is capable to identify the gene-specific type of relationship between gene copy number and mRNA expression. Moreover, it tests the strength of the association and provides confidence intervals. We illustrate PLRS using glioblastoma data from The Cancer Genome Atlas. © 2013 The Author