Investigation of Polymer–Plasticizer Blends as SH-SAW Sensor Coatings for Detection of Benzene in Water with High Sensitivity and Long-Term Stability

We report the first-ever direct detection of benzene in water at concentrations below 100 ppb (parts per billion) using acoustic wave (specifically, shear-horizontal surface acoustic wave, SH-SAW) sensors with plasticized polymer coatings. Two polymers and two plasticizers were studied as materials for sensor coatings. For each polymer–plasticizer combination, the influence of the mixing ratio of the blend on the sensitivity to benzene was measured and compared to commercially available polymers that were used for BTEX (benzene, toluene, ethylbenzene, and xylene) detection in previous work. After optimizing the coating parameters, the highest sensitivity and lowest detection limit for benzene were found for a 1.25 μm thick sensor coating of 17.5%-by-weight diisooctyl azelate-polystyrene on the tested acoustic wave device. The calculated detection limit was 45 ppb, with actual sensor responses to concentrations down to 65 ppb measured directly. Among the sensor coatings that showed good sensitivity to benzene, the best long-term stability was found for a 1.0 μm thick coating of 23% diisononyl cyclohexane-1,2-dicarboxylate-polystyrene, which was studied here because it is known to show no detectable leaching in water. The present work demonstrates that, by varying type of plasticizer, mixing ratio, and coating thickness, the mechanical and chemical properties of the coatings can be conveniently tailored to maximize analyte sorption and partial chemical selectivity for a given class of analytes as well as to minimize acoustic-wave attenuation in contact with an aqueous phase at the operating frequency of the sensor device

Power Sector Opportunities for Reducing Carbon Dioxide Emissions: Colorado

President Obama announced a national climate plan in June 2013 and directed the U.S. Environmental Protection Agency (EPA) to set carbon pollution standards for the power sector. Once EPA establishes those standards, states will implement their own plans for achieving those reductions. In this fact sheet, WRI examines existing tools Colorado can use to reduce power plant emissions

The Effects of Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) on Brown Adipogenesis in Stem Cell Culture

Polyunsaturated fatty acids (PUFAs), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are major maternal dietary supplements due to their positive benefits on neurological tissue growth during the first 12 weeks of gestation. Previous studies show that EPA and DHA inhibit muscle formation but promote adipogenesis. However, no research has addressed the question whether high intake of EPA and DHA affects brown fat development during gestation. The objective of this study was to measure the effect of EPA and DHA supplement on brown adipogenesis and potential pathways related to mitochondrial biosynthesis using fibroblasts as in vitro model. Using Oil-Red-O staining and PCR testing, lipid droplet formation and tested six genes were examined and PGC1α presented statistically significant difference from the control group when treated with PUFAs. Results indicated that PGC1α gene expression can be to be alternated by EPA and DHA treatment. Mitochondrial biosynthesis can potentially be promoted by increased PGC1α gene expression. However, the lipid droplets accumulated in the PUFAs treated group show an unknown mechanism of the n-3 PUFA on adipogenesis that needs to be revealed

The Tragedy of Distrust in the Implementation of Federal Environmental Law

The relationship between the EPA and Congress Since the founding of the EPA in 1970 has been marked by congressional oversight that has seriously frustrated the development and implementation of federal environmental protection policy. A destructive cycle has emerged: agency distrust has led to the failure of its policies, creating further distrust and further failure

Power Sector Opportunities for Reducing Carbon Dioxide Emissions: Minnesota

President obama announced a national climate plan in June 2013 and directed the U.S. Environmental Protection agency (EPa) to set carbon pollution standards for the power sector. once EPa establishes those standards, states will implement their own plans for achieving those reductions. In this fact sheet, WRI examines existing tools Minnesota can use to reduce power plant emissions

Power Sector Opportunities for Reducing Carbon Dioxide Emissions: Michigan

President Obama announced a national climate plan in June 2013 and directed the U.S. Environmental Protection Agency (EPA) to set carbon pollution standards for the power sector. Once EPA establishes those standards, states will implement their own plans for achieving reductions. In this fact sheet, WRI examines existing tools Michigan can use to reduce power plant emissions

Forest cover estimation in Ireland using radar remote sensing: a comparative analysis of forest cover assessment methodologies

Quantification of spatial and temporal changes in forest cover is an essential component of forest monitoring programs. Due to its cloud free capability, Synthetic Aperture Radar (SAR) is an ideal source of information on forest dynamics in countries with near-constant cloud-cover. However, few studies have investigated the use of SAR for forest cover estimation in landscapes with highly sparse and fragmented forest cover. In this study, the potential use of L-band SAR for forest cover estimation in two regions (Longford and Sligo) in Ireland is investigated and compared to forest cover estimates derived from three national (Forestry2010, Prime2, National Forest Inventory), one pan-European (Forest Map 2006) and one global forest cover (Global Forest Change) product. Two machine-learning approaches (Random Forests and Extremely Randomised Trees) are evaluated. Both Random Forests and Extremely Randomised Trees classification accuracies were high (98.1–98.5%), with differences between the two classifiers being minimal (<0.5%). Increasing levels of post classification filtering led to a decrease in estimated forest area and an increase in overall accuracy of SAR-derived forest cover maps. All forest cover products were evaluated using an independent validation dataset. For the Longford region, the highest overall accuracy was recorded with the Forestry2010 dataset (97.42%) whereas in Sligo, highest overall accuracy was obtained for the Prime2 dataset (97.43%), although accuracies of SAR-derived forest maps were comparable. Our findings indicate that spaceborne radar could aid inventories in regions with low levels of forest cover in fragmented landscapes. The reduced accuracies observed for the global and pan-continental forest cover maps in comparison to national and SAR-derived forest maps indicate that caution should be exercised when applying these datasets for national reporting

Addressing Uncertainty in TMDLS: Short Course at Arkansas Water Resources Center 2001 Annual Conference

Management of a critical natural resource like water requires information on the status of that resource. The US Environmental Protection Agency (EPA) reported in the 1998 National Water Quality Inventory that more than 291,000 miles of assessed rivers and streams and 5 million acres of lakes do not meet State water quality standards. This inventory represents a compilation of State assessments of 840,000 miles of rivers and 17.4 million acres of lakes; a 22 percent increase in river miles and 4 percent increase in lake acres over their 1996 reports. Siltation, bacteria, nutrients and metals were the leading pollutants of impaired waters, according to EPA. The sources of these pollutants were presumed to be runoff from agricultural lands and urban areas. EPA suggests that the majority of Americans-over 218 million-live within ten miles of a polluted waterbody. This seems to contradict the recent proclamations of the success of the Clean Water Act, the Nation\u27s water pollution control law. EPA also claims that, while water quality is still threatened in the US, the amount of water safe for fishing and swimming has doubled since 1972, and that the number of people served by sewage treatment plants has more than doubled

The impact of fish oil fatty-acids on post-prandial vascular reactivity.

Progressive loss of vascular reactivity and increased vascular tone with age are being increasingly recognised as significant cardiovascular disease (CVD) risk factors. The vasculature has emerged as a target for dietary strategies to modify these progressions. Our previous data suggest that inclusion of fish oil in a high-fat test meal improves postprandial vascular reactivity in healthy men. The primary aim of this project was to determine the individual effects of the fish oil fatty acids, eicosapentaenoic acid (EPA) versus docosahexaenoic acid (DHA) on post-prandial vascular reactivity and to identify underlying molecular mechanisms of these effects. In this study, the acute effects of a single dose (4.16g) of EPA, DHA and placebo oil on postprandial vascular reactivity were determined in men categorised as being at a 1.5 relative risk of CVD in a double-blind randomised crossover trial. Measures of vascular tone and function, alongside an endothelium dependent measure of vascular reactivity, were taken along with blood samples, at baseline and at 4 hours in order to coincide with the anticipated peak plasma concentration of these fatty acids. These blood samples were utilised for assessment of biomarkers associated with changes in vascular tone and postprandial whole blood culture (WBC). WBC was conducted to investigate the effect of changes in the postprandial lipidome, dependent on EPA and DHA consumption, on cytokine production. Response to intervention according to genotype was also determined retrospectively. We observed that DHA (p=0.04) but not EPA (p=0.06) significantly reduced Augmentation Index (AI) postprandially when compared to control. AI was reduced by 13.3% and 11.3% in response to DHA and EPA respectively. In addition, our data shows for the first time, that levels of the vasoactive n-3 PUFA epoxide and diol metabolites are subject to large changes post consumption of physiological levels of EPA and DHA. Our data also suggests there is wide inter-individual variability in circulating levels of these compounds, which may in part explain inter-individual responsiveness to EPA and DHA. We were not able to observe changes in plasma nitrite or H2S levels postprandially, suggesting that EPA and DHA dependent changes in vascular tone may be mediated in part by their vasoactive epoxide and diol metabolites. However, whole Blood Culture experiments did not show a significant effect on any of the cytokines or growth factors investigated, before or after correction for BMI and AGE. Finally, our investigations of response to treatment by genotype suggested a novel interaction between the PPAR-ƴ rs1801282 polymorphism, DHA consumption and improvements in postprandial triglyceridemia. The findings of this thesis emphasise the differential effects of EPA and DHA in the vasculature and the inter-individual responsiveness to these nutrients