Browsing by Author "Gohlke, Julia"

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    Climate change and physical activity: ambient temperature and urban trail use in Texas
    Lanza, Kevin; Gohlke, Julia; Wang, Suwei; Sheffield, Perry E.; Wilhelmi, Olga (Springer, 2022-05)
    Individuals in the USA are insufficiently active, increasing their chronic disease risk. Extreme temperatures may reduce physical activity due to thermal discomfort. Cooler climate studies have suggested climate change may have a net positive effect on physical activity, yet research gaps remain for warmer climates and within-day physical activity patterns. We determined the association between ambient temperatures (contemporary and projected) and urban trail use in a humid subtropical climate. At a trail in Austin, TX, five electronic counters recorded hourly pedestrian and cyclist counts in 2019. Weather data were acquired from World Weather Online. Generalized additive models estimated the association between temperature and trail counts. We then combined the estimated exposure-response relation with weather projections from climate models for intermediate (RCP4.5) and high (RCP8.5) emissions scenarios by NASA NEX-GDDP. From summer to autumn to spring to winter, hourly trail counts shifted from bimodal (mid-morning and early-evening peaks) to one mid-day peak. Pedestrians were more likely to use the trail between 7 and 27 degrees C (45-81 degrees F) with peak use at 17 degrees C (63 degrees F) and cyclists between 15 and 33 degrees C (59-91 degrees F) with peak use at 27 degrees C (81 degrees F) than at temperature extremes. A net decrease in trail use was estimated by 2041-2060 (RCP4.5: pedestrians = -4.5%, cyclists = - 1.1%; RCP8.5: pedestrians = - 6.6%, cyclists = - 1.6%) and 2081-2100 (RCP4.5: pedestrians= -7.5%, cyclists= - 1.9%; RCP8.5: pedestrians= - 16%, cyclists= -4.5%). Results suggest climate change may reduce trail use. We recommend interventions for thermal comfort at settings for physical activity.
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    Identifying exposure pathways mediating adverse birth outcomes near active surface mines in Central Appalachia
    Ruktanonchai, Corrine W.; McKnight, Molly X.; Buttling, Lauren; Kolivras, Korine N.; Krometis, Leigh-Anne H.; Gohlke, Julia (Lippincott Williams & Wilkins, 2022-06)
    Background: Previous work has determined an association between proximity to active surface mining within Central Appalachia and an increased risk of preterm birth (PTB) and low birthweight (LBW). Multiple potential exposure pathways may exist; however, including inhalation of particulate matter (airshed exposure), or exposure to impacted surface waters (watershed exposure). We hypothesize that this relationship is mediated by exposure to contaminants along one or both of these pathways. Methods: We geolocated 194,084 birth records through health departments in WV, KY, VA, and TN between 1990 and 2015. We performed a mediation analysis, iteratively including within our models: (a) the percent of active surface mining within 5 km of maternal residence during gestation; (b) the cumulative surface mining airshed trajectories experienced during gestation; and (c) the percent of active surface mining occurring within the watershed of residency during gestation. Results: Our baseline models found that active surface mining was associated with an increased odds of PTB (1.09, 1.05-1.13) and LBW (1.06, 1.02-1.11), controlling for individual-level predictors. When mediators were added to the baseline model, the association between active mining and birth outcomes became nonsignificant (PTB: 0.48, 0.14-1.58; LBW 0.78, 0.19-3.00), whereas the association between PTB and LBW remained significant by airshed exposure (PTB: 1.14, 1.11-1.18; LBW: 1.06, 1.03-1.10). Conclusions: Our results found that surface mining airsheds at least partially explained the association between active mining and adverse birth outcomes, consistent with a hypothesis of mediation, while mediation via the watershed pathway was less evident.