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– Disparities in incident stroke risk among women by race and ethnicity persist. Few studies report the distribution and association of stroke risk factors by age group among a diverse sample of women.

A fluorescent sensor for the determination of Ag+by time-gated mode is proposed. The method is based on Ag+-induced formation of quantum dot/DNA/gold nanoparticle complexes. Two ssDNA strands (strand A and strand B) are designed which contain C–C mismatched base pairs that can specifically react with Ag+. The water-soluble long-lifetime fluorescence quantum dots (Mn:CdS/ZnS) functionalized with strand A are selected as the fluorophore. The gold nanoparticles (GNPs) which are labeled with strand B, acted as the quencher. When Ag+is absent in the sample solution, DNA-modified GNPs and Mn:CdS/ZnS were in the freedom state, the fluorescence signal of Mn:CdS/ZnS is obviously strong. When Ag+are present in the sample solution, a DNA duplex is formed because of the strong binding ability between Ag+and cytosine bases and formed stable C–Ag+–C structures. As a result, the Mn:CdS/ZnS and the GNPs are brought into close proximity, which caused the fluorescence quenching of the Mn:CdS/ZnS due to the nanometal surface energy transfer (NSET) between the Mn:CdS/ZnS and GNPs. This fluorescent sensor could present a satisfactory specificity and selectivity for Ag+. Meanwhile, the detection limit of Ag+was estimated to be 7.9 nM.

This study categorizes older adults living in rural areas by denture status, assesses the frequency of wearing dentures during meals, and determines whether denture status or use is associated with dietary quality or the number of foods avoided. A multi-ethnic population-based sample of adults ≥60 years (N = 635) in the rural United States was interviewed. Survey included denture use, removing dentures before eating, and foods avoided due to oral health problems. Dietary intakes were converted into Healthy Eating Index-2005 scores. Sixty percent wore removable dentures of some type; 55% never, 27% sometimes, and 18% always removed dentures when eating. More frequent removal was associated with lower dietary quality and more foods avoided. Those with severe tooth loss had the lowest dietary quality and avoided the most foods. Many rural older adults wear dentures. Learning how they adapt to denture use will offer insight into their nutritional self-management and help explain differences in dietary quality.

Background: We have developed an animal model of alcohol self‐administration that initially employs schedule‐induced polydipsia (SIP) to establish reliable ethanol consumption under open access (22 h/d) conditions with food and water concurrently available. SIP is an adjunctive behavior that is generated by constraining access to an important commodity (e.g., flavored food). The induction schedule and ethanol polydipsia generated under these conditions affords the opportunity to investigate the development of drinking typologies that lead to chronic, excessive alcohol consumption.

Temporal microarray gene expression profiles allow characterization of gene function through time dynamics of gene coexpression within the same genetic pathway. In this paper, we define and estimate a global time shift characteristic for each gene via least squares, inferred from pairwise curve alignments. These time shift characteristics of individual genes reflect a time ordering that is derived from ob- served temporal gene expression profiles. Once these time shift characteristics are obtained for each gene, they can be entered into further analyses, such as clustering. We illustrate the proposed methodology using Drosophila embryonic development and yeast cell-cycle gene expression profiles, as well as simulations. Feasibility is demonstrated through the successful recovery of time ordering. Estimated time shifts for Drosophila maternal and zygotic genes provide excellent discrimination between these two categories and confirm known genetic pathways through the time order of gene expression. The application to yeast cell-cycle data establishes a natural time order of genes that is in line with cell-cycle phases. The method does not require periodicity of gene expression profiles. Asymptotic justifications are also provided.

Introduction:Social isolation, or lack of social network ties, independently predicts incident heart failure (HF) in middle-aged adults (mediated through depressive symptoms). However, it is unknown whether social isolation predicts HF in older adults and if so, what mediates and moderates the association. These questions are important given that the risks of HF and social isolation increase with age.Objectives:To 1) examine whether socially isolated Women?s Health Initiative (WHI) participants had higher HF incidence than those who were not; 2) explore whether depressive symptoms mediate the association; and 3) assess the impact of race/ethnicity, perceived social support, stressful life events, and caregiving as potential effect modifiers.Methods:The sample included 44,174 racially/ethnically diverse WHI participants (mean age at baseline: 63 years) who had adjudicated data on incident HF requiring hospitalization. Women were classified as socially isolated if they were not married and had no religious or community ties. Depressive symptoms were measured using the 8-item Burnham short version of the Center for Epidemiologic Studies- Depression scale. Perceived social support was measured using 9 items from the Medical Outcomes Study social support scale. We assessed 10 stressful life events using a modified questionnaire from the Beta-Blocker Heart Attack Trial. We used a single item to assess caregiving.Results:Over a median 15.0 years follow-up, 6% (n=2148) HF incidence was observed among 35,586 women, and 8% (n=2800) were socially isolated. In an unadjusted model, women who were socially isolated had a 33% higher risk of incident HF than those who were not isolated (HR 1.33; 95% CI 1.15-1.54). In models fully adjusted for demographic, clinical and behavioral variables, general health, and physical functioning, socially isolated women had a 19% higher risk of developing HF (HR 1.19, 95% CI 1.03-1.39). Depressive symptoms did not mediate the association, nor did it differ by race/ethnicity, perceived support, life stressors, or caregiving.Conclusions:Our findings suggest a modest association between self-reported social isolation and incident HF. Future studies should examine other mediators (e.g. loneliness) of this association.

Motivation: Temporal gene expression profiles provide an important characterization of gene function, as biological systems are predominantly developmental and dynamic. We propose a method of classifying collections of temporal gene expression curves in which individual expression profiles are modeled as independent realizations of a stochastic process. The method uses a recently developed functional logistic regression tool based on functional principal components, aimed at classifying gene expression curves into known gene groups. The number of eigenfunctions in the classifier can be chosen by leave-one-out cross-validation with the aim of minimizing the classification error. Results: We demonstrate that this methodology provides low-error-rate classification for both yeast cell-cycle gene expression profiles and Dictyostelium cell-type specific gene expression patterns. It also works well in simulations. We compare our functional principal components approach with a B-spline implementation of functional discriminant analysis for the yeast cell-cycle data and simulations. This indicates comparative advantages of our approach which uses fewer eigenfunctions/base functions. The proposed methodology is promising for the analysis of temporal gene expression data and beyond. Availability: MATLAB programs are available upon request. Contact: ileng@wfubmc.edu Supplementary information: Supplementary materials are available on the journal's website.