26 research outputs found
A Geologically Based Indoor-Radon Potential Map of Kentucky
We combined 71,930 short-term (median duration 4 days) home radon test results with 1:24,000-scale bedrock geologic map coverage of Kentucky to produce a statewide geologically based indoor-radon potential map. The test results were positively skewed with a mean of 266 Bq/m3, median of 122 Bq/m3, and 75th percentile of 289 Bq/m3. We identified 106 formations with ≥10 test results. Analysis of results from 20 predominantly monolithologic formations showed indoor-radon concentrations to be positively skewed on a formation-by-formation basis, with a proportional relationship between sample means and standard deviations. Limestone (median 170 Bq/m3) and dolostone (median 130 Bq/m3) tended to have higher indoor-radon concentrations than siltstones and sandstones (median 67 Bq/m3) or unlithified surficial deposits (median 63 Bq/m3). Individual shales had median values ranging from 67 to 189 Bq/m3; the median value for all shale values was 85 Bq/m3. Percentages of values falling above the U.S. Environmental Protection Agency (EPA) action level of 148 Bq/m3 were sandstone and siltstone: 24%, unlithified clastic: 21%, dolostone: 46%, limestone: 55%, and shale: 34%. Mississippian limestones, Ordovician limestones, and Devonian black shales had the highest indoor-radon potential values in Kentucky. Indoor-radon test mean values for the selected formations were also weakly, but statistically significantly, correlated with mean aeroradiometric uranium concentrations. To produce a map useful to nonspecialists, we classified each of the 106 formations into five radon-geologic classes on the basis of their 75th percentile radon concentrations. The statewide map is freely available through an interactive internet map service
Geospatial data analysis in Russia’s geoweb
The chapter examines the role of geospatial data in Russia’s online ecosystem. Facilitated by the rise of geographic information systems and user-generated content, the distribution of geospatial data has blurred the line between physical spaces and their virtual representations. The chapter discusses different sources of these data available for Digital Russian Studies (e.g., social data and crowdsourced databases) together with the novel techniques for extracting geolocation from various data formats (e.g., textual documents and images). It also scrutinizes different ways of using these data, varying from mapping the spatial distribution of social and political phenomena to investigating the use of geotag data for cultural practices’ digitization to exploring the use of geoweb for narrating individual and collective identities online
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Associations between long-term aircraft noise exposure, cardiovascular disease, and mortality in US cohorts of female nurses
Background:There is limited research examining aircraft noise and cardiovascular disease (CVD) risk. The objective of this study was to investigate associations of aircraft noise with CVD among two US cohorts, the Nurses’ Health Study (NHS) and Nurses’ Health Study II (NHSII).Methods:Between 1994 and 2014, we followed 57,306 NHS and 60,058 NHSII participants surrounding 90 airports. Aircraft noise was modeled above 44 A-weighted decibels (dB(A)) and linked to geocoded addresses. Based on exposure distributions, we dichotomized exposures at 50 dB(A) and tested sensitivity of this cut-point by analyzing aircraft noise as categories (<45, 45–49, 50–54, ≥55) and continuously. We fit cohort-specific Cox proportional hazards models to estimate relationships between time-varying day-night average sound level (DNL) and CVD incidence and CVD and all-cause mortality, adjusting for fixed and time-varying individual- and area-level covariates. Results were pooled using random effects meta-analysis.Results:Over 20 years of follow-up, there were 4529 CVD cases and 14,930 deaths. Approximately 7% (n = 317) of CVD cases were exposed to DNL ≥50 dB(A). In pooled analyses comparing ≥50 with <50 dB(A), the adjusted hazard ratio for CVD incidence was 1.00 (95% confidence interval: 0.89, 1.12). The corresponding adjusted hazard ratio for all-cause mortality was 1.02 (95% confidence interval: 0.96, 1.09). Patterns were similar for CVD mortality in NHS yet underpowered.Conclusions:Among participants in the NHS and NHSII prospective cohorts who generally experience low exposure to aircraft noise, we did not find adverse associations of aircraft noise with CVD incidence, CVD mortality, or all-cause mortality
Long-term aircraft noise exposure and risk of hypertension in the Nurses' Health Studies
Aircraft noise can affect populations living near airports. Chronic exposure to aircraft noise has been associated with cardiovascular disease, including hypertension. However, previous studies have been limited in their ability to characterize noise exposures over time and to adequately control for confounders.The aim of this study was to examine the association between aircraft noise and incident hypertension in two cohorts of female nurses, using aircraft noise exposure estimates with high spatial resolution over a 20-year period.We obtained contour maps of modeled aircraft noise levels over time for 90 U.S. airports and linked them with geocoded addresses of participants in the Nurses' Health Study (NHS) and Nurses' Health Study II (NHS II) to assign noise exposure for 1994–2014 and 1995–2013, respectively. We used time-varying Cox proportional hazards models to estimate hypertension risk associated with time-varying noise exposure (dichotomized at 45 and 55 dB(A)), adjusting for fixed and time-varying confounders. Results from both cohorts were pooled via random effects meta-analysis.In meta-analyses of parsimonious and fully-adjusted models with aircraft noise dichotomized at 45 dB(A), hazard ratios (HR) for hypertension incidence were 1.04 (95% CI: 1.00, 1.07) and 1.03 (95% CI: 0.99, 1.07), respectively. When dichotomized at 55 dB(A), HRs were 1.10 (95% CI: 1.01, 1.19) and 1.07 (95% CI: 0.98, 1.15), respectively. After conducting fully-adjusted sensitivity analyses limited to years in which particulate matter (PM) was obtained, we observed similar findings. In NHS, the PM-unadjusted HR was 1.01 (95% CI: 0.90, 1.14) and PM-adjusted HR was 1.01 (95% CI: 0.89, 1.14); in NHS II, the PM-unadjusted HR was 1.08 (95% CI: 0.96, 1.22) and the PM-adjusted HR was 1.08 (95% CI: 0.95, 1.21). Overall, in these cohorts, we found marginally suggestive evidence of a positive association between aircraft noise exposure and hypertension.•We examined associations between aircraft noise and incident hypertension.•We found marginally suggestive associations, adjusting for confounders.•Air pollution did not confound the relationships between noise and hypertension.•We examined modifiers and found indications with smoking
Association of social distancing and face mask use with risk of COVID-19
Estimating the effectiveness of COVID-19 control measures requires large prospective data including symptoms and personal risk factors. Here, the authors used data from smartphone-based application and found that individual face mask use was associated with a 64% reduced risk of COVID-19 symptoms