scholarly journals Characterization of atmospheric aerosol in the US Southeast from ground- and space-based measurements over the past decade

2012 ◽  
Vol 5 (7) ◽  
pp. 1667-1682 ◽  
Author(s):  
E. J. Alston ◽  
I. N. Sokolik ◽  
O. V. Kalashnikova
Keyword(s):  
Environmental Protection Agency ◽  
Regional Scale ◽  
Correlation Coefficients ◽  
The State ◽  
Study Region ◽  
The Past ◽  
The Us ◽  
Us Epa ◽  
Terra Satellite

Abstract. This study examines how aerosols measured from the ground and space over the US Southeast change temporally over a regional scale during the past decade. PM2.5 (particulate matter with aerodynamic diameter >2.5 micrometers) data consist of two datasets that represent the measurements that are used for regulatory purposes by the US EPA (Environmental Protection Agency) and continuous measurements used for quickly disseminating air quality information. AOD (aerosol optical depth) data come from three NASA sensors: the MODIS sensors onboard Terra and Aqua satellites and the MISR sensor onboard the Terra satellite. We analyze all available data over the state of Georgia from 2000–2009 of both types of aerosol data. The analysis reveals that during the summer the large metropolitan area of Atlanta has average PM2.5 concentrations that are 50% more than the remainder of the state. Strong seasonality is detected in both the AOD and PM2.5 datasets, as evidenced by a threefold increase of AOD from mean winter values to mean summer values, and the increase in PM2.5 concentrations is almost twofold over the same period. Additionally, there is agreement between MODIS and MISR onboard the Terra satellite during the spring and summer, having correlation coefficients of 0.64 and 0.71, respectively. Monthly anomalies were used to determine the presence of a trend in all considered aerosol datasets. We found negative linear trends for both the monthly AOD anomalies from MODIS onboard Terra and the PM2.5 datasets, which are statistically significant. Decreasing trends were also found for MISR onboard Terra and MODIS onboard Aqua, but those trends were not statistically significant. The observed decrease in AOD and PM2.5 concentrations may be indicative of the brightening over the study region during the past decade.

scholarly journals Characterization of atmospheric aerosol in the US Southeast from ground- and space-based measurements over the past decade

2011 ◽  
Vol 4 (6) ◽  
pp. 7559-7595
Author(s):  
E. J. Alston ◽  
I. N. Sokolik ◽  
O. V. Kalashnikova
Keyword(s):  
Regional Scale ◽  
Correlation Coefficients ◽  
The State ◽  
The Past ◽  
The Us ◽  
Us Epa ◽  
Terra Satellite ◽  
Strong Seasonality ◽  
Good Agreement

Abstract. This study examines how aerosols measured from the ground and space over the US Southeast change temporally over a regional scale during the past decade. PM2.5 data consist of two datasets that represent the measurements that are used for regulatory purposes by the US EPA and continuous measurements used for quickly disseminating air quality information. AOD data comes from three NASA sensors: the MODIS sensors onboard Terra and Aqua satellites and the MISR sensor onboard the Terra satellite. We analyze all available data over the state of Georgia from 2000–2009 of both types of aerosol data. The analysis reveals that during the summer the large metropolitan area of Atlanta has average PM2.5 concentrations that are 50% more than the remainder of the state. Strong seasonality is detected in both the AOD and PM2.5 datasets; as evidenced by a threefold increase of AOD from mean winter values to mean summer values, and the increase in PM2.5 concentrations is almost twofold from over the same period. Additionally, there is good agreement between MODIS and MISR onboard the Terra satellite during the spring and summer having correlation coefficients of 0.64 and 0.71, respectively. Monthly anomalies were used to determine the presence of a trend in all considered aerosol datasets. We found negative linear trends in both the monthly AOD anomalies from MODIS onboard Terra and the PM2.5 datasets, which are statistically significant for α = 0.05. Decreasing trends were also found for MISR onboard Terra and MODIS onboard Aqua, but those trends were not statistically significant.

scholarly journals Simulation of a biogas cleaning process using different amines

2018 ◽  
Vol 27 (47) ◽  
Author(s):  
Guillermo Sepúlveda ◽  
Luis Eduardo Jaimes ◽  
Leonardo Pacheco ◽  
Carlos Alirio Díaz
Keyword(s):  
Environmental Protection Agency ◽  
Landfill Gas ◽  
Cleaning Process ◽  
Fuel Gas ◽  
Combustion Properties ◽  
The Us ◽  
Us Epa ◽  
Combustible Gases ◽  
Combustion Processes ◽  
Landfill Gas Emissions

The use of biogas generated in landfills has gained importance in developing countries like Colombia. Taking into account that this biogas presents poor combustion properties that make interchangeability with other combustible gases difficult, the elimination of gases and vapors, such as CO2 and H2O, through a cleaning process, in which the biogas is converted to biomethane, improves the biogas properties as a fuel gas for general use. In this work, we simulated the generation of biogas at El Carrasco sanitary landfill in Bucaramanga, using the US EPA (United States Environmental Protection Agency) landfill gas emissions model. Additionally, we simulated the biogas cleaning process to extract the remaining moisture using the ProMax software; for this, we used three different amines (MDEA, MEA, and DEA), followed by a glycol dehydration process. The results showed that the amine MEA produced the largest increase in the concentration of CH4 (90.37 %) for the biogas generated in the landfill. Furthermore, dehydration with glycol was an efficient process to obtain a gas with a high percentage of methane (91.47 %) and low water presence (1.27 %); this would allow the use of biomethane in conventional industrial combustion processes and power generation.

Population Issues and Reproductive Politics

2013 ◽  
Author(s):  
Rickie Solinger
Keyword(s):  
United States ◽  
Population Growth ◽  
The United States ◽  
The State ◽  
Reproductive Politics ◽  
The Past ◽  
United States Today ◽  
The Us

What is the state of population growth in the United States today, and how is it affected by immigration? According to the 2010 census, the US population has grown 9.7 percent (adding about 27 million people, including about 13 million immigrants) during the past...

scholarly journals Geochemical Behavior of Uranium and Radon in Groundwater of Jurassic Granite Area, Icheon, Middle Korea

Water ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1278 ◽  
Author(s):  
Byong Wook Cho ◽  
Chang Oh Choo
Keyword(s):  
Standard Deviation ◽  
Environmental Protection Agency ◽  
Maximum Contaminant Level ◽  
Contaminant Level ◽  
Low Concentrations ◽  
Wide Range ◽  
The Us ◽  
Us Epa ◽  
Independent Behavior ◽  
Radon Concentrations

Uranium concentrations (a total of 82 samples) in groundwater in Icheon, middle Korea, showed a wide range from 0.02 to 1640 μg/L with a mean of 56.77 μg/L, a median of 3.03 μg/L, and a standard deviation of 228.63 μg/L. Most groundwater samples had quite low concentrations: 32.9% were below 1 μg/L, while 15.9% exceeded 30 μg/L, the maximum contaminant level (MCL) of the US EPA (Environmental Protection Agency). Radon concentrations also ranged widely from 1.48 to 865.8 Bq/L. Although the standard deviation of radon was large (151.8 Bq/L), the mean was 211.29 Bq/L and the median was 176.86 Bq/L. Overall, 64.6% of the samples exceeded the alternative maximum contaminant level (AMCL) of the US EPA (148 Bq/L). According to statistical analyses, there was no close correlations between uranium and radon, but there were correlations between uranium and redox potential (Eh) (−0.54), dissolved oxygen (DO) (−0.50), HCO3− (0.45), Sr (0.65), and SiO2 (−0.44). Radon showed independent behavior with respect to most components in groundwater. Uranium concentrations in groundwater increased with increasing water–rock interactions. Anomalously high uranium and radon concentrations in groundwater are preferentially localized in granite areas and spatial distributions are remarkably heterogeneous.

scholarly journals The contribution of marine organics to the air quality of the western United States

2010 ◽  
Vol 10 (15) ◽  
pp. 7415-7423 ◽  
Author(s):  
B. Gantt ◽  
N. Meskhidze ◽  
A. G. Carlton
Keyword(s):  
United States ◽  
Air Quality ◽  
San Francisco ◽  
Atmospheric Chemistry ◽  
Environmental Protection Agency ◽  
Regional Scale ◽  
The United States ◽  
Coastal Areas ◽  
Western United States ◽  
The Us

Abstract. The contribution of marine organic emissions to the air quality in coastal areas of the western United States is studied using the latest version of the US Environmental Protection Agency (EPA) regional-scale Community Multiscale Air Quality (CMAQv4.7) modeling system. Emissions of marine isoprene, monoterpenes, and primary organic matter (POM) from the ocean are implemented into the model to provide a comprehensive view of the connection between ocean biology and atmospheric chemistry and air pollution. Model simulations show that marine organics can increase the concentration of PM2.5 by 0.1–0.3 μg m−3 (up to 5%) in some coastal cities such as San Francisco, CA. This increase in the PM2.5 concentration is primarily attributed to the POM emissions, with small contributions from the marine isoprene and monoterpenes. When marine organic emissions are included, organic carbon (OC) concentrations over the remote ocean are increased by up to 50% (25% in coastal areas), values consistent with recent observational findings. This study is the first to quantify the air quality impacts from marine POM and monoterpenes for the United States, and it highlights the need for inclusion of marine organic emissions in air quality models.

scholarly journals Evaluation of US state pollinators using 3 evidence-based policymaking frameworks

2021 ◽  
Author(s):  
Kaitlin Stack Whitney ◽  
Briana Burt Stringer
Keyword(s):  
Best Practices ◽  
Science Policy ◽  
Environmental Protection Agency ◽  
State Level ◽  
The State ◽  
Evidence Based ◽  
Conservation Policies ◽  
The Us ◽  
State Policymaking ◽  
Us Federal Government

After the US federal government created a national pollinator protection plan in 2015, many states followed with their own. Since their goal is to promote pollinating insect conservation, we wanted to know whether the state plans are using best practices for evidence-based science policy. In early 2019 we found and downloaded every existing, publicly available US state pollinator protection plan. We then used content analysis to assess the goals, scope, and implementation of state-level pollinator protection plans across the US. This analysis was conducted using three distinct frameworks for evidence-based policymaking: US Department of Interior Adaptive Resources Management (ARM), US Environmental Protection Agency management pollinator protection plan (MP3) guidance, and Pew Trusts Pew-MacAthur Results First Project elements of evidence-based state policymaking (PEW) framework. Then we scored them using the framework criteria, to assess whether the plans were using known best practices for evidence based policymaking. Of the 31 states with a state pollinator plan, Connecticut was the state with the lowest total score across the three evaluation frameworks. The state with the highest overall scores, across the three frameworks, was Missouri. Most states did not score highly on the majority of the frameworks. Overall, many state plans were lacking policy elements that address monitoring, evaluation, and adjustment. These missing elements impact the ability of states to achieve their conservation goals. Our results indicate that states can improve their pollinator conservation policies to better match evidence-based science policy guidance, regardless of which framework is used.

scholarly journals Principles and techniques towards successful development of enzyme-linked immunosorbent assay (ELISA) for dioxin analysis

2021 ◽  
Author(s):  
Wei Zhang
Keyword(s):  
Immunosorbent Assay ◽  
Environmental Protection Agency ◽  
High Resolution Mass Spectrometry ◽  
Enzyme Linked Immunosorbent Assay ◽  
Environmental Matrices ◽  
Successful Development ◽  
Trace Level ◽  
The Us ◽  
Us Epa ◽  
Technical Details

Dioxins are highly toxic, persistent and bio-accumulative compounds. Laboratory detection of dioxins in various environmental matrices is one of the most technically demanding and expensive tasks in analytical chemistry.The cost to analyze a soil sample by conventional gas chromatography-high resolution mass spectrometry (GC-HRMS) is approximately $1,900 USC accordign to the Unisted States Environmental Protection Agency (US EPA) (Billets, 2005). As an alternative, enzyme-linked immunosorbent assay (ELISA) for dioxin analysis has been commercially available for over a decade and recognized as the US EPA Method 3025. However, assay attributes need to be examined, especially at trace level detection. In this study, sources of error in ELISA, such as background contamination and dioxin-like polycholrinated biphenyl (dl-BCB) cross-reactions have been investigated. Quality assurance data on spikes have been reviewed and the recovery was estimated to be 70%. Technical details that are crucial for the performance of dioxin in ELISA were also identified and addressed.

Pandemic Reemergence and Four Waves of Excess Mortality Coinciding With the 1918 Influenza Pandemic in Michigan: Insights for COVID-19

2021 ◽  
Vol 111 (3) ◽  
pp. 430-437
Author(s):  
Siddharth Chandra ◽  
Julia Christensen ◽  
Madhur Chandra ◽  
Nigel Paneth
Keyword(s):  
Broad Spectrum ◽  
Excess Mortality ◽  
Influenza Pandemic ◽  
The State ◽  
Viral Pathogens ◽  
Monthly Data ◽  
Social Distancing ◽  
The Past ◽  
The Us ◽  
1918 Influenza

The global influenza pandemic that emerged in 1918 has become the event of reference for a broad spectrum of policymakers seeking to learn from the past. This article sheds light on multiple waves of excess mortality that occurred in the US state of Michigan at the time with insights into how epidemics might evolve and propagate across space and time. We analyzed original monthly data on all-cause deaths by county for the 83 counties of Michigan and interpreted the results in the context of what is known about the pandemic. Counties in Michigan experienced up to four waves of excess mortality over a span of two years, including a severe one in early 1920. Some counties experienced two waves in late 1918 while others had only one. The 1920 wave propagated across the state in a different manner than the fall and winter 1918 waves. The twin waves in late 1918 were likely related to the timing of the statewide imposition of a three-week social distancing order. Michigan’s experience holds sobering lessons for those who wish to understand how immunologically naïve populations encounter novel viral pathogens.

scholarly journals Structural characterization of Polycyclic Aromatic Hydrocarbon degrading enzymes

2014 ◽  
Vol 70 (a1) ◽  
pp. C472-C472
Author(s):  
Juliana Coitinho ◽  
Debora Costa ◽  
Samuel Guimaraes ◽  
Cintia Neves ◽  
Simara Araujo ◽  
...  
Keyword(s):  
Aromatic Hydrocarbons ◽  
Environmental Protection Agency ◽  
Metabolic Activation ◽  
Degradation Pathway ◽  
Laboratory Animals ◽  
International Agency ◽  
Naphthalene Degradation ◽  
The Us ◽  
Polycyclic Aromatic

Polycyclic aromatic hydrocarbons (PAHs) are a group of aromatic hydrocarbons composed of two or more fused rings and include naphthalene, phenanthrene, pyrene and benzo[a]pyrene amongst others. Exposure to naphthalene has been associated with several toxic manifestations in humans and laboratory animals, with the lens of the eye and the lungs being most sensitive [1]. Additionally, this compound has been reclassified as a possible human carcinogen by the US Environmental Protection Agency and the International Agency for Research on Cancer. It has recently been suggested that naphthalene undergoes metabolic activation to 1,2-naphthoquinone, which reacts with DNA, leading to the formation of apurinic sites on DNA and depurinating DNA adducts [2]. Moreover, a number of studies have attested to the carcinogenic and mutagenic properties of more complex PAHs, suggesting the need for further work on the elimination of these compounds from the environment. The Gram-negative bacterium P. putida G7 is among the best studied naphthalene-degrading species. The genes associated with naphthalene metabolism are localized on NAH7, an 83 kilobase plasmid. In P. putida G7 the naphthalene-oxidation genes are organized into two operons under salicylate control. The first operon (upper naphthalene-degradation pathway) includes the genes nahAaAbAcAdBCDEF, which code for the conversion of naphthalene to salicylate, while the second operon (lower pathway) includes the genes nahGTHINLOMKJ responsible for the oxidation of salicylate via the catechol meta-cleavage pathway [3]. In the last years, our group focused on the structure elucidation and the kinetic characterization of the P. putida G7 enzymes involved in the naphthalene degradation pathway. We intend to present these results which basically describe the 3D structures of NahB, NahF, NahG, NahI, NahK and NahK/NahL complex and some kinetic data of these enzymes and their mutants. This work was supported by FAPEMIG, CNPq and VALE S.A.

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