Environmental Tobacco Smoke Exposure in Relation to Family Characteristics, Stressors and Chemical Co-Exposures in California Girls.

Childhood environmental tobacco smoke (ETS) exposure is a risk factor for adverse health outcomes and may disproportionately burden lower socioeconomic status groups, exacerbating health disparities. We explored associations of demographic factors, stressful life events, and chemical co-exposures, with cotinine levels, among girls in the CYGNET Study. Data were collected from families of girls aged 6-8 years old in Northern California, through clinic exams, questionnaires and biospecimens (n = 421). Linear regression and factor analysis were conducted to explore predictors of urinary cotinine and co-exposure body burdens, respectively. In unadjusted models, geometric mean cotinine concentrations were higher among Black (0.59 ug/g creatinine) than non-Hispanic white (0.27), Asian (0.32), or Hispanic (0.34) participants. Following adjustment, living in a rented home, lower primary caregiver education, and lack of two biologic parents in the home were associated with higher cotinine concentrations. Girls who experienced parental separation or unemployment in the family had higher unadjusted cotinine concentrations. Higher cotinine was also associated with higher polybrominated diphenyl ether and metals concentrations. Our findings have environmental justice implications as Black and socio-economically disadvantaged young girls experienced higher ETS exposure, also associated with higher exposure to other chemicals. Efforts to reduce ETS and co-exposures should account for other disparity-related factors

Nitrogen and Fiber Digestion in Sheep Fed Fresh-Frozen and Field-Dried High and Low Tannin Sericea Lespedeza

Field-drying reduces extractable condensed tannin (CT) of sericea lespedeza [Lespedeza cuneata (Dum-Cours) G. Don], but effects on specific bound and unbound forms of CT and the relationship to protein and fiber digestion in ruminants are unclear. Intake and digestibility of fresh-frozen and field-dried high- and low-tannin sericea were investigated in a feeding trial with sheep (Ovis spp.). Field-drying had no effect on crude protein (CP) and fiber content of sericea, but shifted CT from extractable to bound forms. Digestion coefficients for CP, neutral detergent fiber (NDF), and acid detergent fiber (ADF) were lower for high-tannin sericea than the low-tannin type. Field-drying had no effect on fiber digestibility but increased CP digestibility and N retention in sheep fed high-tannin forage. Apparent digestion of CT was high for all treatments, but this is likely due to difficulty in analyzing CT in fecal material. Nutritional effects of CT in sericea lespedeza are related to both total CT and proportion of bound and unbound CT in the forage

Accuracy and Precision of Tidal Wetland Soil Carbon Mapping in the Conterminous United States

Tidal wetlands produce long-term soil organic carbon (C) stocks. Thus for carbon accounting purposes, we need accurate and precise information on the magnitude and spatial distribution of those stocks. We assembled and analyzed an unprecedented soil core dataset, and tested three strategies for mapping carbon stocks: applying the average value from the synthesis to mapped tidal wetlands, applying models fit using empirical data and applied using soil, vegetation and salinity maps, and relying on independently generated soil carbon maps. Soil carbon stocks were far lower on average and varied less spatially and with depth than stocks calculated from available soils maps. Further, variation in carbon density was not well-predicted based on climate, salinity, vegetation, or soil classes. Instead, the assembled dataset showed that carbon density across the conterminous united states (CONUS) was normally distributed, with a predictable range of observations. We identified the simplest strategy, applying mean carbon density (27.0 kg C m−3), as the best performing strategy, and conservatively estimated that the top meter of CONUS tidal wetland soil contains 0.72 petagrams C. This strategy could provide standardization in CONUS tidal carbon accounting until such a time as modeling and mapping advancements can quantitatively improve accuracy and precision

Controlled Thiol-ene Polymer Microsphere Production Using a Low-Frequency Acoustic Excitation Coaxial Flow Method

A novel technique for the production of thiol-ene microspheres using acoustic resonance and coaxial flow is reported. The method utilizes low-frequency acoustically driven mechanical perturbations to disrupt the flow of a thiol-ene liquid jet, resulting in small thiol-ene droplets that are photochemically polymerized to yield thiol-ene microspheres. Tuning of the frequency, amplitude, and monomer solution viscosity are critical parameters impacting the diameter of the microspheres produced. Characterization by optical microscopy, scanning electron microscopy, and dynamic light scattering reveal microspheres of diameters \u3c10 mu m, with narrow particle distributions. (C) 2016 Elsevier Ltd. All rights reserved

Residential proximity to traffic and female pubertal development

Traffic-related air pollution (TRAP) has been linked with several adverse health outcomes, including preterm birth and low birth weight, which are both related to onset of puberty. No studies to date have investigated the association between TRAP and altered pubertal timing