Search

Your search keyword '"Davis, Karelyn"' showing total 17 results
Start Over Author "Davis, Karelyn" Publication Year Range Last 10 years
17 results on '"Davis, Karelyn"'

12. Exposure to Free and Conjugated Forms of Bisphenol A and Triclosan among Pregnant Women in the MIREC Cohort

Author

Arbuckle, Tye E., primary, Marro, Leonora, additional, Davis, Karelyn, additional, Fisher, Mandy, additional, Ayotte, Pierre, additional, Bélanger, Patrick, additional, Dumas, Pierre, additional, LeBlanc, Alain, additional, Bérubé, René, additional, Gaudreau, Éric, additional, Provencher, Gilles, additional, Faustman, Elaine M., additional, Vigoren, Eric, additional, Ettinger, Adrienne S., additional, Dellarco, Michael, additional, MacPherson, Susan, additional, and Fraser, William D., additional

Published
2015
Full Text
View/download PDF

13. Persistent organic pollutants (POPs) and metals in primiparous women: a comparison from Canada and Mexico

Author

Adlard, Bryan, primary, Davis, Karelyn, additional, Liang, Chun Lei, additional, S. Curren, Meredith, additional, Rodríguez-Dozal, Sandra, additional, Riojas-Rodríguez, Horacio, additional, Hernández-Ávila, Mauricio, additional, Foster, Warren, additional, Needham, Larry, additional, Wong, Lee-Yang, additional, Weber, Jean-Philippe, additional, Marro, Leonora, additional, Leech, Tara, additional, and Van Oostdam, Jay, additional

Published
2014
Full Text
View/download PDF

14. Comparison of Persistent Organic Pollutants (Pops) and Metals in Primiparous Women from Canada and Mexico

Author

Adlard*, Bryan, primary, Davis, Karelyn, additional, Liang, Chun Lei, additional, Curren, Meredith, additional, Rodríguez-Dozal, Sandra, additional, Riojas-Rodríguez, Horacio, additional, Foster, Warren, additional, Wong, Lee-Yang, additional, Weber, Jean-Philippe, additional, Marro, Leonora, additional, and Van Oostdam, Jay, additional

Published
2014
Full Text
View/download PDF

16. Research. Exposure to Free and Conjugated Forms of Bisphenol A and Triclosan among Pregnant Women in the MIREC Cohort.

Author

Arbuckle, Tye E., Marro, Leonora, Davis, Karelyn, Fisher, Mandy, Ayotte, Pierre, Bélanger, Patrick, Dumas, Pierre, LeBlanc, Alain, Bérubé, René, Gaudreau, Éric, Provencher, Gilles, Faustman, Elaine M., Vigoren, Eric, Ettinger, Adrienne S., Dellarco, Michael, MacPherson, Susan, and Fraser, William D.

Subjects
PHENOL analysis, CONFIDENCE intervals, MATERNAL age, PHENOLS, RESEARCH funding, TRICLOSAN, DATA analysis software, DESCRIPTIVE statistics, ODDS ratio, PREGNANCY
Abstract

Background: Bisphenol A (BPA) and triclosan (TCS) are two nonpersistent chemicals that have been frequently measured in spot urine samples from the general population but less so in pregnant women; however, data are limited on the free (bioactive) and conjugated forms of these phenols. Objectives: The Maternal-Infant Research on Environmental Chemicals (MIREC) Study addressed these data gaps by utilizing stored maternal urine samples from a large multicenter cohort study of Canadian pregnant women. Methods: Concentrations of free and conjugated forms of BPA and TCS were measured in about 1,890 first-trimester urine samples by ultra performance liquid chromatograpy-tandem mass spectrometry using isotope dilution. Results: The glucuronides of BPA and TCS were the predominant forms of these chemicals measured (detected in 95% and 99% of samples, respectively), whereas the free forms were detected in 43% and 80% of samples, respectively. The geometric mean urinary concentrations for glucuronides of BPA and TCS were 0.80 μg/L (95% CI: 0.75, 0.85) and 12.30 μg/L (95% CI: 11.08, 13.65), respectively. Significant predictors of BPA included maternal age < 25 vs. ≥ 35 years, current smoking, low vs. high household income, and low vs. high education. For TCS, urinary concentrations were significantly higher in women ≥ 25 years of age, never vs. current smokers, and women with high household income and high education. Conclusions: The results from this study represent the largest national-level data on urinary concentrations of free and conjugated forms of BPA and TCS in pregnant women and suggest that maternal characteristics predicting elevated urinary concentrations of these phenols largely act in opposite directions. Citation: Arbuckle TE, Marro L, Davis K, Fisher M, Ayotte P, Bélanger P, Dumas P, LeBlanc A, Bérubé R, Gaudreau É, Provencher G, Faustman EM, Vigoren E, Ettinger AS, Dellarco M, MacPherson S, Fraser WD. 2015. Exposure to free and conjugated forms of bisphenol A and triclosan among pregnant women in the MIREC cohort. Environ Health Perspect 123:277-284; http://dx.doi.org/10.1289/ehp.1408187 [ABSTRACT FROM AUTHOR]

Published
2015
Full Text
View/download PDF

17. Constrained inference for generalized linear models with incomplete covariate data.

Author

Davis, Karelyn A., Sinha, Sanjoy K., and Park, Chul Gyu

Subjects
*LINEAR statistical models, *GENERALIZATION, *MISSING data (Statistics), *CLINICAL trials, *COMPUTER simulation, *LIKELIHOOD ratio tests
Abstract

Missing data are common in many experiments, including surveys, clinical trials, epidemiological studies, and environmental studies. Unconstrained likelihood inferences for generalized linear models (GLMs) with nonignorable missing covariates have been studied extensively in the literature. However, parameter orderings or constraints may occur naturally in practice, and thus the efficiency of a statistical method may be improved by incorporating parameter constraints into the likelihood function. In this paper, we consider constrained inference for analysing GLMs with nonignorable missing covariates under linear inequality constraints on the model parameters. Specifically, constrained maximum likelihood (ML) estimation is based on the gradient projection expectation maximization approach. Further, we investigate the asymptotic null distribution of the constrained likelihood ratio test (LRT). Simulations study the empirical properties of the constrained ML estimators and LRTs, which demonstrate improved precision of these constrained techniques. An application to contaminant levels in an environmental study is also presented. [ABSTRACT FROM AUTHOR]

Published
2015
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results