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Detecting Cyanobacteria Toxins: The Human Health Impact Of An Environmental Problem, Lillian E. Naimie 2019 Colby College

Detecting Cyanobacteria Toxins: The Human Health Impact Of An Environmental Problem, Lillian E. Naimie

Honors Theses

Cyanobacteria blooms are a growing concern in the world, as they can form a dense and sometimes toxin scum on water bodies. This paper will outline and discuss the environmental conditions that produce cyanobacteria bloom with a focus on the toxins produced by blooms and specifically the detection of these toxins through two analytical methods. Of the various toxins cyanobacteria are capable of producing, this paper will focus on microcystins and BMAA, a family of hepatotoxins and a specific neurotoxin respectively. The two analytical methods discussed are liquid chromatography coupled mass spectrometry and ELISA kit techniques. The advantages and drawbacks …


Effect Of Iron On The Oxidative Capacity Of Carbonaceous Nanoparticles, Daniel Chavez 2019 Central Washington University

Effect Of Iron On The Oxidative Capacity Of Carbonaceous Nanoparticles, Daniel Chavez

All Master's Theses

Inhalation of ambient particulate matter (PM2.5) emitted during combustion of fuels has negative impacts on human health. Triggered in part by the generation of reactive oxygen species (ROS) that lead to oxidative stress, significant gaps exist in the understanding of the detailed chemistry of these detrimental effects. Trace metals and carbonaceous material of the nanometer-sized particles contained in PM2.5 have been implicated as key players in causing these effects. Here, the role of Fe is investigated with carbonaceous nanoparticles (CNP) while mimicking simple cellular conditions. By adding environmentally representative and controlled concentrations of Fe(II) or Fe(III) to …


Extreme Molecular Diversity In Biomass Burning Atmospheric Organic Aerosol Observed Through Ultrahigh Resolution Mass Spectrometry, Matthew Brege 2019 Michigan Technological University

Extreme Molecular Diversity In Biomass Burning Atmospheric Organic Aerosol Observed Through Ultrahigh Resolution Mass Spectrometry, Matthew Brege

Dissertations, Master's Theses and Master's Reports

Ambient atmospheric aerosol is ubiquitous in the atmosphere, originating from a variety of natural and man-made sources. These microscopic particles have profound impacts on the global climate system as well as human health. The organic fraction of atmospheric aerosol is an extremely complex mixture which is not yet fully characterized. These unknown organic aerosol species contribute to the uncertainty in the effect of aerosol on climate and uncertainty in overall ambient aerosol toxicity. Light absorbing organic aerosol can interact with incoming solar radiation and contribute to atmospheric heating; however, the source apportionment and overall fate of these absorbing organic aerosol …


Pursue Undergraduate Research Journal Volume 2 (Issue 1) 2019, 2019 Prairie View A&M University

Pursue Undergraduate Research Journal Volume 2 (Issue 1) 2019

Pursue: Undergraduate Research Journal

The scholarly journal, “PURSUE: Undergraduate Research Journal” (ISSN 2473-6201), provides undergraduates an avenue to publish their original research abstracts and articles in the following areas: psychology, sociology, biology, chemistry, physics, engineering, computer science, mathematics, humanities, agriculture, architecture, health, business, and education (this list is not exclusive).

The original research articles included in this journal are peer reviewed and selected by the journal’s Editorial Board. The review process allows undergraduate researchers to receive feedback from notable scientists in their field of study and teach them about the publication process. Publication of their work will not only inform the scientific community; it …


Environmental Forensic Characterization Of Former Rail Yard Soils Located Adjacent To The Statue Of Liberty In The New York/New Jersey Harbor, Diane Hagmann, Michael A. Kruge, Matthew Chi-Hymn Cheung, Maria Mastalerz, José Luis Gallego, Jay Prakash Singh, Jennifer Krumins, Xiaona N. Li, Nina M. Goodey 2019 Montclair State University

Environmental Forensic Characterization Of Former Rail Yard Soils Located Adjacent To The Statue Of Liberty In The New York/New Jersey Harbor, Diane Hagmann, Michael A. Kruge, Matthew Chi-Hymn Cheung, Maria Mastalerz, José Luis Gallego, Jay Prakash Singh, Jennifer Krumins, Xiaona N. Li, Nina M. Goodey

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Identifying inorganic and organic soil contaminants in urban brownfields can give insights into the adverse effects of industrial activities on soil function, ecological health, and environmental quality. Liberty State Park in Jersey City (N.J., USA) once supported a major rail yard that had dock facilities for both cargo and passenger service; a portion remains closed to the public, and a forest developed and spread in this area. The objectives of this study were to: 1) characterize the organic and inorganic compounds in Liberty State Park soils and compare the findings to an uncontaminated reference site (Hutcheson Memorial Forest); and 2) …


Biogeochemical Response To Vegetation And Hydrologic Change In An Alaskan Boreal Fen Ecosystem, Danielle L. Rupp 2019 Michigan Technological University

Biogeochemical Response To Vegetation And Hydrologic Change In An Alaskan Boreal Fen Ecosystem, Danielle L. Rupp

Dissertations, Master's Theses and Master's Reports

Boreal peatlands store approximately one third of the earth’s terrestrial carbon, locked away in currently waterlogged and frozen conditions. Peatlands of boreal and arctic ecosystems are affected increasingly by shifting hydrology caused by climate change. The consequences of these relatively rapid ecosystem changes on carbon cycling between the landscape and the atmosphere could provide an amplifying feedback to climate warming. Alternatively, the advancement of terrestrial vegetation into once waterlogged soils could uptake carbon as a sink. Previous work suggests that fens will become an increasingly dominant landscape feature in the boreal. However, studies investigating fens, their response to hydrologic and …


Recent Trends In Stratospheric Chlorine From Very Short‐Lived Substances, Ryan Hossaini, Elliot Atlas, Sandip S. Dhomse, Martyn P. Chipperfield, Peter F. Bernath, Anton M. Fernando, Jens Mühle, Amber A. Leeson, Stephen A. Montzka, Wuhu Feng 2019 Old Dominion University

Recent Trends In Stratospheric Chlorine From Very Short‐Lived Substances, Ryan Hossaini, Elliot Atlas, Sandip S. Dhomse, Martyn P. Chipperfield, Peter F. Bernath, Anton M. Fernando, Jens Mühle, Amber A. Leeson, Stephen A. Montzka, Wuhu Feng

Chemistry & Biochemistry Faculty Publications

Very short‐lived substances (VSLS), including dichloromethane (CH2Cl2), chloroform (CHCl3), perchloroethylene (C2Cl4), and 1,2‐dichloroethane (C2H4Cl2), are a stratospheric chlorine source and therefore contribute to ozone depletion. We quantify stratospheric chlorine trends from these VSLS (VSLCltot) using a chemical transport model and atmospheric measurements, including novel high‐altitude aircraft data from the NASA VIRGAS (2015) and POSIDON (2016) missions. We estimate VSLCltot increased from 69 (±14) parts per trillion (ppt) Cl in 2000 to 111 (±22) ppt Cl in 2017, with >80% delivered to …


Shelf Inputs And Lateral Transport Of Mn, Co, And Ce In The Western North Pacific Ocean, Peter L. Morton, William M. Landing, Alan M. Shiller, Amy Moody, Thomas D. Kelly, Michael Bizimis, John R. Donat, Eric H. De Carlo, Joseph Shacat 2019 Old Dominion University

Shelf Inputs And Lateral Transport Of Mn, Co, And Ce In The Western North Pacific Ocean, Peter L. Morton, William M. Landing, Alan M. Shiller, Amy Moody, Thomas D. Kelly, Michael Bizimis, John R. Donat, Eric H. De Carlo, Joseph Shacat

Chemistry & Biochemistry Faculty Publications

The margin of the western North Pacific Ocean releases redox-active elements like Mn, Co, and Ce into the water column to undergo further transformation through oxide formation, scavenging, and reductive dissolution. Near the margin, the upper ocean waters enriched in these elements are characterized by high dissolved oxygen, low salinity, and low temperature, and are a source of the North Pacific Intermediate Water. High dissolved concentrations are observed across the Western Subarctic Gyre, with a rapid decrease in concentrations away from the margin and across the subarctic-subtropical front. The particulate concentrations of Mn, Co, and Ce are also high in …


Phosgene In The Upper Troposphere And Lower Stratosphere: A Marker For Product Gas Injection Due To Chlorine-Containing Very Short Lived Substances, Jeremy J. Harrison, Martyn P. Chipperfield, Ryan Hossaini, Christopher D. Boone, Sandip Dhomse, Wuhu Feng, Peter F. Bernath 2019 Old Dominion University

Phosgene In The Upper Troposphere And Lower Stratosphere: A Marker For Product Gas Injection Due To Chlorine-Containing Very Short Lived Substances, Jeremy J. Harrison, Martyn P. Chipperfield, Ryan Hossaini, Christopher D. Boone, Sandip Dhomse, Wuhu Feng, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

Abstract: Phosgene in the atmosphere is produced via the degradation of carbon tetrachloride, methyl chloroform, and a number of chlorine‐containing very short lived substances (VSLS). These VSLS are not regulated by the Montreal Protocol even though they contribute to stratospheric ozone depletion. While observations of VSLS can quantify direct stratospheric source gas injection, observations of phosgene in the upper troposphere/lower stratosphere can be used as a marker of product gas injection of chlorine‐containing VSLS. In this work we report upper troposphere/lower stratosphere measurements of phosgene made by the ACE‐FTS (Atmospheric Chemistry Experiment Fourier Transform Spectrometer) instrument and compare with results …


Spatial Patterns Of Particulate Organic Carbon Concentrations And Isotopic Signatures Across A Salinity Gradient In A River Dominated Estuary, Lauren E. Alvaro, John C. Lehrter, Mai Fung 2019 Florida Gulf Coast University

Spatial Patterns Of Particulate Organic Carbon Concentrations And Isotopic Signatures Across A Salinity Gradient In A River Dominated Estuary, Lauren E. Alvaro, John C. Lehrter, Mai Fung

Gulf and Caribbean Research

No abstract provided.


Method Considerations For Compound Identification In Complex Mixtures Using Electrospray Ionization Ultrahigh Resolution Mass Spectrometry, Tyler Leverton 2019 Michigan Technological University

Method Considerations For Compound Identification In Complex Mixtures Using Electrospray Ionization Ultrahigh Resolution Mass Spectrometry, Tyler Leverton

Dissertations, Master's Theses and Master's Reports

Biomass burning aerosols are highly complex organic mixtures of thousands of components with consequences for global climate. Complex mixture component identification requires accurate mass measurement capability to separate components on a milli-Dalton scale, frequently using ultrahigh resolution mass spectrometry with electrospray ionization. Certain sample preparations and the ionization process may introduce artifacts that obscure the composition of the sample. Two method considerations were explored using isotopically labeled 15NH4OH and MeOH-d3 to track artifact formation in biomass burning samples. Informatics techniques and a custom molecular formula assignment software were used to identify the isotopic atoms in artifact …


Novel Adsorbent For Industrial Wastewater Treatment Applications, Islam M. Al-Akraa, Ahmed Y. Zakaria Eng, Dalia A. Ali Eng, Hany A. Elazab Dr, Hoda A. Elsawy Dr 2019 The British University in Egypt

Novel Adsorbent For Industrial Wastewater Treatment Applications, Islam M. Al-Akraa, Ahmed Y. Zakaria Eng, Dalia A. Ali Eng, Hany A. Elazab Dr, Hoda A. Elsawy Dr

Chemical Engineering

In this study, the hydroxyapatite powder is investigated for both of methylene blue and thymol blue in aqueous solution. The physical and chemical properties of the adsorbent were evaluated systematically using the different techniques including Microsoft Excel programming, linear regression model and also the coefficient of determination. Batch adsorption experiments were conducted to determine the effect of contact time, solution pH, initial dye concentrations, and also the adsorbent dosage on adsorption. The adsorption kinetic parameters confirmed the better fitting of pseudo-second order kinetic model for both of methylene blue and thymol blue. The isotherm data of methylene blue and thymol …


Nanomaterials For Double-Stranded Rna Delivery, Stuart Lichtenberg 2019 University of Kentucky

Nanomaterials For Double-Stranded Rna Delivery, Stuart Lichtenberg

Theses and Dissertations--Plant and Soil Sciences

RNA interference has enormous potential as a potent, specific, and environmentally friendly alternative to small molecule pesticides for crop protection. The use of exogenous double-stranded RNA offers flexibility in targeting and use in crops in which transgenic manipulation is not an option. The combination of RNAi with nanotechnology offers further advantages that are not available with dsRNA alone. In this work, I have evaluated several different combinations of nanomaterials and polymers for use in RNAi-based pest control systems. First, I have characterized the use of chitosan/dsRNA polyplex nanoparticles for gene knockdown using the model nematode Caenorhabditis elegans. Though chitosan/dsRNA …


Spatial Fingerprinting Of Biogenic And Anthropogenic Volatile Organic Compounds In An Arid Unsaturated Zone, Christopher T. Green, Wentai Luo, Christopher H. Conaway, Karl B. Haase, Ronald J. Baker 2019 US Geological Survey

Spatial Fingerprinting Of Biogenic And Anthropogenic Volatile Organic Compounds In An Arid Unsaturated Zone, Christopher T. Green, Wentai Luo, Christopher H. Conaway, Karl B. Haase, Ronald J. Baker

Chemistry Faculty Publications and Presentations

Subsurface volatile organic compounds (VOCs) can pose risks to human and environmental health and mediate biological processes. Volatile organic compounds have both anthropogenic and biogenic origins, but the relative importance of these sources has not been explored in subsurface environments. This study synthesized 17 yr of VOC data from the Amargosa Desert Research Site in Nevada with the goal of improving understanding of spatial and temporal variations that distinguish sources of VOCs from a landfill and from ambient sources including biogenic VOCs (bVOCs). Gas samples were collected from 1999 to 2016 from an array of shallow sample points (0.5- and …


Synthesis Of N-Heterocyclic Molecules And Their Applicability Towards Ion Sensing: Polymeric Chemosensors, Aikohi M. Ugboya 2019 Georgia Southern University

Synthesis Of N-Heterocyclic Molecules And Their Applicability Towards Ion Sensing: Polymeric Chemosensors, Aikohi M. Ugboya

College of Graduate Studies: Theses & Dissertations

Critical to biological and environmental processes are anions because often times their relative concentration in our body can be an indicator of one’s well-being. Therefore, highly sensitive and cost-efficient methods for ions recognition is necessary for human health. In recent times, polymeric chemosensors have become a vital tool for sensing ions because of its higher sensitivity and good mechanical properties compared to their monomeric counterparts. These sensors are designed to produce a measurable response in the presence of a targeted ion such as an electrochemical or optical signal. The unique structure and the photophysical properties of the 1,2,3-triazole core coupled …


Effect Of Carbonaceous Nanoparticles On Naturally Occurring Iron Reduction By Carboxylates, Ashleen Reddy 2019 Central Washington University

Effect Of Carbonaceous Nanoparticles On Naturally Occurring Iron Reduction By Carboxylates, Ashleen Reddy

All Master's Theses

The emission of ambient particulate matter (PM) is regulated by many institutions due to the detrimental effects on health, environment and climate; yet many underlying mechanisms of PM reactivity are still not well understood. In the current study, the effect of carbonaceous nanoparticles (CNPs), contained within ultrafine PM (particle diameter ≤ 100 nm), is investigated on naturally occurring processes that increase the abundance of bioavailable iron. Enhancing iron bioavailability (i) increases primary productivity of iron-limited microorganisms, affecting the carbon cycle and global climate, and (ii) increase toxicity of inhaled particles through the associated production of reactive oxygen species (ROS). Specifically, …


Seasonal Soil Carbon Fluxes In Transitioning Agricultural Soils In Central Washington State: Relations To Land-Use, Environmental Factors And Soil Carbon-Nitrogen Characteristics, Brandon Kautzman 2019 Central Washington University

Seasonal Soil Carbon Fluxes In Transitioning Agricultural Soils In Central Washington State: Relations To Land-Use, Environmental Factors And Soil Carbon-Nitrogen Characteristics, Brandon Kautzman

All Master's Theses

Changing agricultural land-use practices to increase soil carbon sequestration contributes to climate change mitigation and improved food security by moving CO2 from the atmosphere into soil as soil organic carbon (SOC). In 2016, a farm in Thorp, Washington, Spoon Full Farm, began converting land historically farmed using conventional methods of tillage and synthetic fertilizers to conservation farming methods with direct seeding and organic soil amendments with a goal of sequestering carbon in the soil. This project evaluates relationships of soil CO2 respiration and net ecological exchange (NEE) with land-use types, seasonal environmental factors (air temperature, relative humidity, soil …


Oxidative Depolymerization Of Lignin To Low Molecular Weight Aromatics, Yang Song 2019 University of Kentucky

Oxidative Depolymerization Of Lignin To Low Molecular Weight Aromatics, Yang Song

Theses and Dissertations--Chemistry

To date, most lignocellulosic biorefinery strategies have focused on optimizing conversion of cellulose to ethanol, leaving lignin as an underutilized biomass constituent. Lignin is engineered by nature with the intent to protect plants from chemical and biological attack; this leaves lignin with high structural irregularity and recalcitrance, rendering conversion of the lignin macromolecule to valuable products particularly challenging. Nevertheless, given that the economics of cellulosic ethanol production are strongly dependent on the value that can be obtained for the lignin co-product, the successful valorization of lignin is a crucial step in the transition towards a bio-based economy.

This thesis focuses …


Investigation Of Thiol-Containing Biomarkers And Their Role In The Exposome, Tracy Gastineau-Stevens 2019 University of Kentucky

Investigation Of Thiol-Containing Biomarkers And Their Role In The Exposome, Tracy Gastineau-Stevens

Theses and Dissertations--Chemistry

Exposomics is an emerging area of study that looks at how the environment around a person or persons affects their overall health. Biomarkers have emerged as useful tools to better understand how the exposome affects a person. In this work, we investigate two potential endogenous biomarkers, homocysteine and glutathione that have been previously implicated in a number of diseases that have been linked to environmental causes. We also investigated an environmental exposure, the fungicide Ziram, which epidemiologically has been linked to diseases. In our investigation, we utilized capillary electrophoresis and capillary electrophoresis-mass spectrometry to develop a method for homocysteine and …


Silicone Wristbands As Passive Samplers For Quantitative Measurement Of Wood Smoke Exposure, Hannah J. Wright 2019 University of Montana

Silicone Wristbands As Passive Samplers For Quantitative Measurement Of Wood Smoke Exposure, Hannah J. Wright

Graduate Student Theses, Dissertations, & Professional Papers

Human exposure to biomass smoke is a health concern worldwide. Although many studies have measured particulate matter in wood smoke as a health concern, exposure to mutagenic and carcinogenic volatile and semivolatile compounds remains understudied. This research introduces a novel method of quantitative measurement of exposure to these compounds using silicone wristbands. The study developed a method to extract analytes of interest from the wristbands and quantify a few volatile organic compounds and polycyclic aromatic hydrocarbons with known ill health effects, and then performed linear regressions between extracted levels and exposure to those analytes using controlled exposure studies. Results indicate …


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