10 research outputs found
Intraurban Variation of Fine Particle Elemental Concentrations in New York City
Few
past studies have collected and analyzed within-city variation
of fine particulate matter (PM<sub>2.5</sub>) elements. We developed
land-use regression (LUR) models to characterize spatial variation
of 15 PM<sub>2.5</sub> elements collected at 150 street-level locations
in New York City during December 2008–November 2009: aluminum,
bromine, calcium, copper, iron, potassium, manganese, sodium, nickel,
lead, sulfur, silicon, titanium, vanadium, and zinc. Summer- and winter-only
data available at 99 locations in the subsequent 3 years, up to November
2012, were analyzed to examine variation of LUR results across years.
Spatial variation of each element was modeled in LUR including six
major emission indicators: boilers burning residual oil; traffic density;
industrial structures; construction/demolition (these four indicators
in buffers of 50 to 1000 m), commercial cooking based on a dispersion
model; and ship traffic based on inverse distance to navigation path
weighted by associated port berth volume. All the elements except
sodium were associated with at least one source, with <i>R</i><sup>2</sup> ranging from 0.2 to 0.8. Strong source-element associations,
persistent across years, were found for residual oil burning (nickel,
zinc), near-road traffic (copper, iron, and titanium), and ship traffic
(vanadium). These emission source indicators were also significant
and consistent predictors of PM<sub>2.5</sub> concentrations across
years
Additional file 1: Table S1 of The associations between daily spring pollen counts, over-the-counter allergy medication sales, and asthma syndrome emergency department visits in New York City, 2002-2012
Correlation matrix of log-transformed tree pollens, weather, and air pollution variables. Figure S1: Year-round daily time-series of over-the-counter allergy medications sales, asthma ED visits syndrome, and log-transformed ash pollen concentrations. Figure S2: Year-to-year average peak date correspondence between tree pollens and OTC allergy medication sales. Figure S3: Individual lag days’ rate ratios for OTC allergy medication sales and asthma syndrome ED visits. Figure S4: Sensitivity analysis using alternative pollen metrics for OTC allergy medication sales and asthma syndrome ED visits. Figure S5. Sensitivity analysis using alternative model specifications for OTC allergy medication sales and asthma syndrome ED visits. (PDF 1467 kb
A Hybrid Approach to Estimating National Scale Spatiotemporal Variability of PM<sub>2.5</sub> in the Contiguous United States
Airborne
fine particulate matter exhibits spatiotemporal variability
at multiple scales, which presents challenges to estimating exposures
for health effects assessment. Here we created a model to predict
ambient particulate matter less than 2.5 ÎĽm in aerodynamic diameter
(PM<sub>2.5</sub>) across the contiguous United States to be applied
to health effects modeling. We developed a hybrid approach combining
a land use regression model (LUR) selected with a machine learning
method, and Bayesian Maximum Entropy (BME) interpolation of the LUR
space-time residuals. The PM<sub>2.5</sub> data set included 104,172
monthly observations at 1464 monitoring locations with approximately
10% of locations reserved for cross-validation. LUR models were based
on remote sensing estimates of PM<sub>2.5</sub>, land use and traffic
indicators. Normalized cross-validated <i>R</i><sup>2</sup> values for LUR were 0.63 and 0.11 with and without remote sensing,
respectively, suggesting remote sensing is a strong predictor of ground-level
concentrations. In the models including the BME interpolation of the
residuals, cross-validated <i>R</i><sup>2</sup> were 0.79
for both configurations; the model without remotely sensed data described
more fine-scale variation than the model including remote sensing.
Our results suggest that our modeling framework can predict ground-level
concentrations of PM<sub>2.5</sub> at multiple scales over the contiguous
U.S
A Hybrid Approach to Estimating National Scale Spatiotemporal Variability of PM<sub>2.5</sub> in the Contiguous United States
Airborne
fine particulate matter exhibits spatiotemporal variability
at multiple scales, which presents challenges to estimating exposures
for health effects assessment. Here we created a model to predict
ambient particulate matter less than 2.5 ÎĽm in aerodynamic diameter
(PM<sub>2.5</sub>) across the contiguous United States to be applied
to health effects modeling. We developed a hybrid approach combining
a land use regression model (LUR) selected with a machine learning
method, and Bayesian Maximum Entropy (BME) interpolation of the LUR
space-time residuals. The PM<sub>2.5</sub> data set included 104,172
monthly observations at 1464 monitoring locations with approximately
10% of locations reserved for cross-validation. LUR models were based
on remote sensing estimates of PM<sub>2.5</sub>, land use and traffic
indicators. Normalized cross-validated <i>R</i><sup>2</sup> values for LUR were 0.63 and 0.11 with and without remote sensing,
respectively, suggesting remote sensing is a strong predictor of ground-level
concentrations. In the models including the BME interpolation of the
residuals, cross-validated <i>R</i><sup>2</sup> were 0.79
for both configurations; the model without remotely sensed data described
more fine-scale variation than the model including remote sensing.
Our results suggest that our modeling framework can predict ground-level
concentrations of PM<sub>2.5</sub> at multiple scales over the contiguous
U.S
Characteristics of the sample of people who inject drugs (PWID), drawn from the 2009 Centers for Disease Control and Prevention’s National HIV Behavior Surveillance.
<p>Characteristics of the sample of people who inject drugs (PWID), drawn from the 2009 Centers for Disease Control and Prevention’s National HIV Behavior Surveillance.</p
Components Generated by the Principal Components Analysis.
<p>Components Generated by the Principal Components Analysis.</p
Bivariate associations between HIV negative status and participant characteristics<sup>1</sup>.
<p>Bivariate associations between HIV negative status and participant characteristics<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0150410#t006fn001" target="_blank"><sup>1</sup></a>.</p
Characteristics of the ZIP Codes (N = 968), Counties (N = 51), and Metropolitan Statistical Areas (MSAs; N = 19) where the 9,077 participants of the 2009 Centers for Disease Control and Prevention’s National HIV Behavioral Surveillance Lived, by Racial/Ethnic Group<sup>1</sup>.
<p>Characteristics of the ZIP Codes (N = 968), Counties (N = 51), and Metropolitan Statistical Areas (MSAs; N = 19) where the 9,077 participants of the 2009 Centers for Disease Control and Prevention’s National HIV Behavioral Surveillance Lived, by Racial/Ethnic Group<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0150410#t004fn001" target="_blank"><sup>1</sup></a>.</p
Multivariable hierarchical generalized linear models regressing the odds of HIV negative status on characteristics of the environments where people who inject drugs (N = 9,077) lived when participating in the National HIV Behavioral Surveillance in 2009<sup>1</sup>.
<p>Multivariable hierarchical generalized linear models regressing the odds of HIV negative status on characteristics of the environments where people who inject drugs (N = 9,077) lived when participating in the National HIV Behavioral Surveillance in 2009<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0150410#t007fn001" target="_blank"><sup>1</sup></a>.</p
Bivariate associations between HIV negative status and (a) features of the environments where people who inject drugs (N = 9,077) lived when participating in the 2009 National HIV Behavioral Surveillance, and (b) participant characteristics<sup>1</sup>.
<p>Bivariate associations between HIV negative status and (a) features of the environments where people who inject drugs (N = 9,077) lived when participating in the 2009 National HIV Behavioral Surveillance, and (b) participant characteristics<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0150410#t005fn001" target="_blank"><sup>1</sup></a>.</p