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BACKGROUND The assessment of air pollution exposure using only community average concentrations may lead to measurement error that lowers estimates of the health burden attributable to poor air quality. To test this hypothesis, we modeled the association between air pollution and mortality using small-area exposure measures in Los Angeles, California. (More)
We conducted an extended follow-up and spatial analysis of the American Cancer Society (ACS) Cancer Prevention Study II (CPS-II) cohort in order to further examine associations between long-term exposure to particulate air pollution and mortality in large U.S. cities. The current study sought to clarify outstanding scientific issues that arose from our(More)
We present a new statistical model for linking spatial variation in ambient air pollution to mortality. The model incorporates risk factors measured at the individual level, such as smoking, and at the spatial level, such as air pollution. We demonstrate that the spatial autocorrelation in community mortality rates, an indication of not fully characterizing(More)
Cohort study designs are often used to assess the association between community-based ambient air pollution concentrations and health outcomes, such as mortality, development and prevalence of disease, and pulmonary function. Typically, a large number of subjects are enrolled in the study in each of a small number of communities. Fixed-site monitors are(More)
In medical and health studies, heterogeneities in clustered count data have been traditionally modeled by positive random effects in Poisson mixed models; however, excessive zeros often occur in clustered medical and health count data. In this paper, we consider a three-level random effects zero-inflated Poisson model for health-care utilization data where(More)
The evaluation of area-specific risks for large fires is of great policy relevance to fire management and prevention. When analyzing data for the burned areas of large fires in Canada, we found that there are dramatic patterns that cannot be adequately modelled by traditional hierarchical modelling assuming spatial autocorrelation. In this paper, we use the(More)
Analysis of longitudinal data with excessive zeros has gained increasing attention in recent years; however, current approaches to the analysis of longitudinal data with excessive zeros have primarily focused on balanced data. Dropouts are common in longitudinal studies; therefore, the analysis of the resulting unbalanced data is complicated by the missing(More)
Excited state solvation plays a very important role in modulating the emission behavior of fluorophores upon excitation. Here, the solvation effects on the local micro-environment around a fluorophore are proposed by investigating the fantastic emission behavior of a novel amyloid fibril marker, NIAD-4, in different alcoholic and aprotic solvents. In(More)
Precipitation is of great importance to agriculture, environment and ecosystem as a regular precipitation pattern is usually vital to healthy plants; excessive or insufficient rainfall can be harmful. Periodic patterns of precipitation can be studied based on regularly observed data over time. Since regularly observed precipitation data are generally skewed(More)
A comparative investigation on the photophysical properties and solvation-related ICT dynamics of three push-pull compounds containing different donors including carbazole, triphenylamine and phenothiazine, was performed. The steady-state spectra and theoretical calculations show the charge transfers from the central donors to the acceptors at each side.(More)