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USF Tampa Graduate Theses and Dissertations

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Full-Text Articles in Physical Sciences and Mathematics

Stochastic Modeling And Analysis Of Energy Commodity Spot Price Processes, Olusegun Michael Otunuga Jun 2014

Stochastic Modeling And Analysis Of Energy Commodity Spot Price Processes, Olusegun Michael Otunuga

USF Tampa Graduate Theses and Dissertations

Supply and demand in the World oil market are balanced through responses to price movement with considerable complexity in the evolution of underlying supply-demand

expectation process. In order to be able to understand the price balancing process, it is important to know the economic forces and the behavior of energy commodity spot price processes. The relationship between the different energy sources and its utility together with uncertainty also play a role in many important energy issues.

The qualitative and quantitative behavior of energy commodities in which the trend in price of one commodity coincides with the trend in price of …


Evolution And Equilibration Of Artificial Morphologic Perturbations In The Form Of Nearshore Berm Nourishments Along The Florida Gulf Coast, Katherine Emily Brutsché Jun 2014

Evolution And Equilibration Of Artificial Morphologic Perturbations In The Form Of Nearshore Berm Nourishments Along The Florida Gulf Coast, Katherine Emily Brutsché

USF Tampa Graduate Theses and Dissertations

Inlets and channels are dredged often to maintain navigation safety. It is beneficial to reintroduce the dredged material back into the littoral system, in the form of beach or nearshore nourishments. Nourishment in the nearshore is becoming an increasingly utilized method, particularly for dredged material that contains more fine sediment than the native beach. This research examines the morphologic evolution of two different nearshore nourishments. A nearshore berm was constructed at Fort Myers Beach, Florida using mixed-sized sediment dredged from a nearby channel. The nearshore berm was placed in water depths between 1.2 and 2.4 m with the berm crest …


A Multi-Period Mixed Integer Linear Programming Model For Desalination And Electricity Co-Generation In Kuwait, Nael Abdulhameed Alqattan Jun 2014

A Multi-Period Mixed Integer Linear Programming Model For Desalination And Electricity Co-Generation In Kuwait, Nael Abdulhameed Alqattan

USF Tampa Graduate Theses and Dissertations

Water is the root of life and the engine that drives agriculture, industry, economy and services. The demand for water often necessitates desalination, particularly in arid coastal environments where there are several desalination technologies in use today such as Multi-Effect Distillation (MED) and Reverse Osmosis (RO). The key utility requirement for technologies such as desalination and population in general include energy in one form or another. Therefore, desalination and co-generation are often integrated. Another key utility is electricity which is generated from either renewable or non-renewable sources. The demands for water and electricity change over time and are subject to …


Topological Data Analysis Of Properties Of Four-Regular Rigid Vertex Graphs, Grant Mcneil Conine Jun 2014

Topological Data Analysis Of Properties Of Four-Regular Rigid Vertex Graphs, Grant Mcneil Conine

USF Tampa Graduate Theses and Dissertations

Homologous DNA recombination and rearrangement has been modeled with a class of four-regular rigid vertex graphs called assembly graphs which can also be represented by double occurrence words. Various invariants have been suggested for these graphs, some based on the structure of the graphs, and some biologically motivated.

In this thesis we use a novel method of data analysis based on a technique known as partial-clustering analysis and an algorithm known as Mapper to examine the relationships between these invariants. We introduce some of the basic machinery of topological data analysis, including the construction of simplicial complexes on a data …


Synthesis, Characterization And Mechanistic Studies Of Biomolecules@Mesomofs, Yao Chen Jun 2014

Synthesis, Characterization And Mechanistic Studies Of Biomolecules@Mesomofs, Yao Chen

USF Tampa Graduate Theses and Dissertations

Encapsulation of biomolecules is of great interest to research advances related to biology, physiology, immunology, and biochemistry, as well as industrial and biomedical applications such as drug delivery, biocatalysis, biofuel, food and cosmetics. Encapsulation provides functional characteristics that are not fulfilled by free biomolecules and stabilizes the fragile biomolecules. In terms of biocatalysis, solid support can often enhance the stability of enzymes, as well as facilitate separation and recovery for reuse while maintaining activity and selectivity. Various kinds of materials have been used for encapsulation of biomolecules, among which, porous materials are an important group. Metal-organic frameworks (MOFs) have attracted …


Can The Usa National Weather Service Heat Index Substitute For Wet Bulb Globe Temperature For Heat Stress Exposure Assessment?, Ivory Iheanacho Jun 2014

Can The Usa National Weather Service Heat Index Substitute For Wet Bulb Globe Temperature For Heat Stress Exposure Assessment?, Ivory Iheanacho

USF Tampa Graduate Theses and Dissertations

Heat stress occurs when the body cannot adequately cool itself due to the combined contributions of metabolic heat, environmental factors and clothing. Heat stress found in the workplace puts employees at risk of developing heat-related illnesses, disorders and could be fatal. The wet bulb globe temperature (WBGT) index is the current method used to assess environmental contributions to heat stress in an occupational setting. The purpose of this thesis was to explore whether the National Weather Service's Heat Index (HI) could substitute for the WBGT Index during occupational heat stress exposure assessment. The possibility of using the HI for heat …


Environment, Rights, And Waste In Bolivia: Addressing Water And Sanitation Processes For Improved Infrastructure, Maryann R. Cairns Jun 2014

Environment, Rights, And Waste In Bolivia: Addressing Water And Sanitation Processes For Improved Infrastructure, Maryann R. Cairns

USF Tampa Graduate Theses and Dissertations

Water and sanitation (WatSan) development projects impact both natural systems and societal structures where they are placed. A complex process of development, including inter-governmental policies, aid agencies, personal relationships, and community politics enhance and constrain the efficacy of these projects. This study presents the many ways in which the WatSan development process has unintended and unexpected returns for certain community groups. Using a political ecology framework, I look at power structures, perceived and projected environmental impacts, multiple stakeholders, and individual discourses to critique how the right to water and sanitation is implemented in a specific community context. This project advances …


Analysis Of Critical Behavior In Magnetic Materials, Dustin David Belyea Jun 2014

Analysis Of Critical Behavior In Magnetic Materials, Dustin David Belyea

USF Tampa Graduate Theses and Dissertations

This work contains a broad study of a variety of magnetic materials undergoing second order phase transitions. In general this leads to an overall increase in information and analytical methods to further the field of magnetocalorics. Specifically, critical aspects of magnetocaloric materials were compared within systems in relation to structure, stoichiometry, magnetic minority phases and magnetic contaminants. Detailed analyses were developed to quantify techniques which were in the past used mainly in a qualitative way, leading to a more complete understanding of how critical phenomena impacts the magnetocaloric response.


Characterization Of Waste Anesthetic Gas Exposures To Veterinary Workers In The Tampa Bay Area, Kyle Vogel Jun 2014

Characterization Of Waste Anesthetic Gas Exposures To Veterinary Workers In The Tampa Bay Area, Kyle Vogel

USF Tampa Graduate Theses and Dissertations

Veterinarians routinely conduct surgical operations on animals while veterinary technicians administer anesthetic gas to sedate the animal prior to an operation. One commonly used anesthetic agent in veterinary clinics is isoflurane. Veterinary workers have the potential to be exposed to this gas during surgical operations. The Occupational Safety and Health Administration (OSHA) does not have a specific Permissible Exposure Limit (PEL) for isoflurane, however The National Institutes for Health (NIH) does advise that workers should not be exposed to isoflurane in concentrations exceeding 2 parts per million (ppm) for an 8 hour Time Weighted Average (TWA).

Animal clinics vary in …


The Use And Effectiveness Of Online Social Media In Volunteer Organizations, Amy J. Connolly Jun 2014

The Use And Effectiveness Of Online Social Media In Volunteer Organizations, Amy J. Connolly

USF Tampa Graduate Theses and Dissertations

Volunteer organizations face two challenges not found in non-volunteer organizations: recruiting and retaining volunteers. While social media use is increasing amongst individuals, its use and effectiveness for volunteer recruitment and retention by volunteer organizations is unknown. The dissertation reports the results of three studies to investigate this important question. Using a mixed-methods approach, it addressed the dual nature of social media and its effectiveness by including volunteer organizations and social media users.

This dissertation found that although volunteer organizations are not using social media effectively, they could virtualize requirements of the recruitment process by focusing on relatable events instead of …


Insights Into The Epitaxial Relationships Between One-Dimensional Nanomaterials And Metal Catalyst Surfaces Using Density Functional Theory Calculations, Debosruti Dutta Jun 2014

Insights Into The Epitaxial Relationships Between One-Dimensional Nanomaterials And Metal Catalyst Surfaces Using Density Functional Theory Calculations, Debosruti Dutta

USF Tampa Graduate Theses and Dissertations

This dissertation involves the study of epitaxial behavior of one-dimensional nanomaterials like single-walled carbon nanotubes and Indium Arsenide nanowires grown on metallic catalyst surfaces. It has been previously observed in our novel microplasma based CVD growth of SWCNTs on Ni-Fe bimetallic nanoparticles that changes in the metal catalyst composition was accompanied by variations in the average metal-metal bond lengths of the nanoparticle and that in turn, affected nanotube chirality distributions. In this dissertation, we have developed a very simplistic model of the metal catalyst in order to explain the nanotube growth of specific nanotube chiralities on various Ni-Fe catalyst surfaces. …


Development And Assessment Of Self-Explaining Skills In College Chemistry Instruction, Adrian Villalta-Cerdas Jun 2014

Development And Assessment Of Self-Explaining Skills In College Chemistry Instruction, Adrian Villalta-Cerdas

USF Tampa Graduate Theses and Dissertations

The prevalent trend in chemistry instruction relies on what has been described as the classroom game. In this model, students take a passive role and the instructor does all the explaining (thinking), and learning is trivialized to knowing the correct answers (memorizing) and being able to produce them when prompted (regurgitating). The generation of explanations is central to scientific and technological development. In the process of figuring out explanations, the generation of inferences relies on the application of skills associated with scientific behaviors (e.g., analytical reasoning and critical thinking). The process of explanation generation causes a deeper analysis and revision …


Inactivation Of Ascaris In Double-Vault Urine-Diverting Composting Latrines In Panama: Methods And Environmental Health Engineering Field Applications, Daragh A. Gibson Jun 2014

Inactivation Of Ascaris In Double-Vault Urine-Diverting Composting Latrines In Panama: Methods And Environmental Health Engineering Field Applications, Daragh A. Gibson

USF Tampa Graduate Theses and Dissertations

The United Nations Millennium Development Goals have prioritized improving access to sanitation, but unfortunately about a third of the global population is still without an improved sanitation source and one billion still practice open defecation. Lack of access to adequate and safe sanitation means the proliferation of dangerous pathogens in the environment, especially soil-transmitted helminths (STHs). In the Bocas del Toro Province of Panama (and similar locations in the world), composting latrines have been built in many of the indigenous communities in the area. They are a form of dry or ecological sanitation and are designed to produce an end …


Diffuse Nutrient Pollution From Residential Catchments, Melissa Rachelle Butcher Jun 2014

Diffuse Nutrient Pollution From Residential Catchments, Melissa Rachelle Butcher

USF Tampa Graduate Theses and Dissertations

Nonpoint source nutrient pollution is diffuse pollution lacking discrete origin and conveyance. This thesis synthesizes and critically reviews research on residential nitrogen and phosphorus loss to stormwater runoff and leaching. The evaluation pulls from research covering influential socio-demographic indicators, such as use of lawn maintenance services and homeowner fertilizer practices. The extent to which such social and economic factors may influence the prevalence and fate of diffuse nutrients in stormwater runoff from residential areas has not been adequately established. Understanding the source and influencing factors of diffuse nutrient pollution is important in order to effectively protect surface and groundwater resources. …


Water And Health In The Nandamojo Watershed Of Costa Rica: Community Perceptions Towards Water, Sanitation, And The Environment, James Mcknight Jun 2014

Water And Health In The Nandamojo Watershed Of Costa Rica: Community Perceptions Towards Water, Sanitation, And The Environment, James Mcknight

USF Tampa Graduate Theses and Dissertations

Understanding the relationships between human health, water, sanitation, and environmental health is a requirement to understanding the challenges that face researchers when it comes to addressing global health relating to water and sanitation. Access to improved water and sanitation is not only a precondition to health, but to all aspects of daily living. Target 7.C of the Millennium Development Goals (MDGs) addresses worldwide disparities in access to improved water and sanitation by calling for the reduction in "half of the proportion of people without sustainable access to safe drinking water and sanitation by 2015". Over 90% of the population of …


Trend Analysis And Modeling Of Health And Environmental Data: Joinpoint And Functional Approach, Ram C. Kafle Jun 2014

Trend Analysis And Modeling Of Health And Environmental Data: Joinpoint And Functional Approach, Ram C. Kafle

USF Tampa Graduate Theses and Dissertations

The present study is divided into two parts: the first is on developing the statistical analysis and modeling of mortality (or incidence) trends using Bayesian joinpoint regression and the second is on fitting differential equations from time series data to derive the rate of change of carbon dioxide in the atmosphere.

Joinpoint regression model identifies significant changes in the trends of the incidence, mortality, and survival of a specific disease in a given population. Bayesian approach of joinpoint regression is widely used in modeling statistical data to identify the points in the trend where the significant changes occur. The purpose …


The Soft Mode Driven Dynamics Of Ferroelectric Perovskites At The Nanoscale: An Atomistic Study, Kevin Mccash May 2014

The Soft Mode Driven Dynamics Of Ferroelectric Perovskites At The Nanoscale: An Atomistic Study, Kevin Mccash

USF Tampa Graduate Theses and Dissertations

The discovery of ferroelectricity at the nanoscale has incited a lot of interest in perovskite ferroelectrics not only for their potential in device application but also for their potential to expand fundamental understanding of complex phenomena at very small size scales. Unfortunately, not much is known about the dynamics of ferroelectrics at this scale. Many of the widely held theories for ferroelectric materials are based on bulk dynamics which break down when applied to smaller scales. In an effort to increase understanding of nanoscale ferroelectric materials we use atomistic resolution computational simulations to investigate the dynamics of polar perovskites. Within …


Statistical Analysis, Modeling, And Algorithms For Pharmaceutical And Cancer Systems, Bong-Jin Choi May 2014

Statistical Analysis, Modeling, And Algorithms For Pharmaceutical And Cancer Systems, Bong-Jin Choi

USF Tampa Graduate Theses and Dissertations

The aim of the present study is to develop a statistical algorithm and model associ- ated with breast and lung cancer patients. In this study, we developed several statistical softwares, R packages, and models using our new statistical approach.

In the present study, we used the five parameters logistic model for determining the optimal doses of a pharmaceutical drugs, including dynamic initial points, an automatic process for outlier detection and an algorithm that develops a graphic user interface(GUI) program. The developed statistical procedure assists medical scientists by reducing their time in determining the optimal dose of new drugs, and can …


Marine Viral Diversity And Spatiotemporal Variability, Dawn Goldsmith May 2014

Marine Viral Diversity And Spatiotemporal Variability, Dawn Goldsmith

USF Tampa Graduate Theses and Dissertations

Marine viruses are the most numerous biological entities in the ocean, with an estimated abundance of 4 x 1030. They merit study not only because of their sheer abundance, but also because of the role they play in the Earth's biogeochemical cycles. Viral lysis of bacteria redirects the flow of nutrients among marine microbes, which ultimately affects the efficiency of the biological pump. Viral diversity is important because most viruses are host-specific. In preying on a certain type of bacteria, viruses affect the diversity and structure of the bacterial community, leading to changes in carbon and nutrient flows. …


Investigation Of Energy Alignment Models At Polymer Interfaces, Wenfeng Wang May 2014

Investigation Of Energy Alignment Models At Polymer Interfaces, Wenfeng Wang

USF Tampa Graduate Theses and Dissertations

The presented study investigated the Induced Density of Interface States (IDIS) model at different polymer interfaces by using photoemission spectroscopy in combination with electrospray deposition.

In recent years, organic electronics have attracted considerable attention due to their advantages of low-cost and easy-fabrication. The performance of such devices crucially depends on the energy barrier that controls the interface charge transfer. A significant effort has been made to explore the mechanisms that determine the direction and magnitude of charge transfer barriers in these devices. As a result of this effort, the IDIS model was developed to predict the energy alignment at metal/organic …


A Synthesis Approach Of Trp-Like Primary Amine Peptoid Side Chains Used In Cyclic Beta-Hairpin - Like Scaffolds, Josanne-Dee Woodroffe May 2014

A Synthesis Approach Of Trp-Like Primary Amine Peptoid Side Chains Used In Cyclic Beta-Hairpin - Like Scaffolds, Josanne-Dee Woodroffe

USF Tampa Graduate Theses and Dissertations

In recent studies it was reported that the D-amino acid containing peptide HYD1 was used in the treatment of necrotic cell death in multiple myeloma cell lines and showed promising biological activity and in vivo activity. It was meaningful to explore strategies for increasing the therapeutic efficacy of HYD1, a linear peptide. These efforts led to the development of MT1-101 (cyclized peptidomimetics), a lead compound that showed increased in vitro activity and in vivo activity. MTI-101 was found to bind the cell adhesion molecule CD44 and induce programmed necrosis in myeloma cell lines. It was important to improve on the …


Algae: Opportunities For Biomass Feedstock Production, Wastewater Treatment And Educational Outreach, Trina Cassandra Halfhide May 2014

Algae: Opportunities For Biomass Feedstock Production, Wastewater Treatment And Educational Outreach, Trina Cassandra Halfhide

USF Tampa Graduate Theses and Dissertations

Algae are a diverse group of simple organisms that lack roots, stems or leaves and are able to use sunlight, carbon dioxide, and nutrients to produce complex compounds, such as carbohydrates, proteins and lipids. These compounds, especially lipids, are highly sought-after by agricultural, nutraceutical and energy interests. Although there is great potential for algae derived biofuels, there are technical and economic challenges associated with their cultivation. Relevant to this dissertation, the environmental impacts associated with algae cultivation can be reduced by using municipal and agricultural wastewaters as a water and nutrient source. This research was divided into three sections to …


Skutterudite Derivatives: A Fundamental Investigation With Potential For Thermoelectric Applications, Kaya Wei May 2014

Skutterudite Derivatives: A Fundamental Investigation With Potential For Thermoelectric Applications, Kaya Wei

USF Tampa Graduate Theses and Dissertations

Thermoelectric devices allow for direct conversion of heat into electricity as well as solid-state refrigeration. The skutterudite family of compounds continues to be of considerable interest both scientifically and technologically due to their unique physical properties, in particular as promising thermoelectric materials. In this thesis, the basic thermoelectric phenomena and some background history on skutterudites will be reviewed. Rhombohedral derivatives of the cubic skutterudite CoSb3, namely Co4-xFexGe6Se6 with x=0, 1, 1.5 (p-type) and rare-earth filled Ce0.13Co4Ge6Se6 and Yb0.14Co4Ge6Se6 (n-type), were synthesized and their synthesis and low temperature transport properties will be discussed.

Reitveld refinement and elemental analysis were used to …


Spatial And Temporal Extent Of A Subsurface Hydrocarbon Intrusion Following The Deepwater Horizon Blowout, Kathleen Watson May 2014

Spatial And Temporal Extent Of A Subsurface Hydrocarbon Intrusion Following The Deepwater Horizon Blowout, Kathleen Watson

USF Tampa Graduate Theses and Dissertations

The Deepwater Horizon (DWH) oil spill in the Gulf of Mexico (GoM) released an estimated 4.9 million barrels of oil between April 20, 2010 and July 15, 2010. An estimated 36% of the oil formed a neutrally buoyant intrusion, containing both dissolved compounds and oil microdroplets, between 1000 and 1300 m depth. This study used geographic information systems software, and data from water samples that were collected as part of the National Resource Damage Assessment (NRDA), to determine that an area of at least 1,600 km2 was exposed to DWH oil. Toxic BTEX (benzene, toluene, ethylbenzene, and …


Study Of The Motility Of Biological Cells By Digital Holographic Microscopy, Xiao Yu May 2014

Study Of The Motility Of Biological Cells By Digital Holographic Microscopy, Xiao Yu

USF Tampa Graduate Theses and Dissertations

In this dissertation, I utilize digital holographic microscopy (DHM) to study the motility of biological cells. As an important feature of DHM, quantitative phase microscopy by digital holography (DH-QPM) is applied to study the cell-substrate interactions and migratory behavior of adhesive cells. The traction force exerted by biological cells is visualized as distortions in flexible substrata. Motile fibroblasts produce wrinkles when attached to a silicone rubber film. For the non-wrinkling elastic substrate polyacrylamide (PAA), surface deformation due to fibroblast adhesion and motility is visualized as tangential and vertical displacement. This surface deformation and the associated cellular traction forces are measured …


Drinking Water In The Developing World: Sources Of Fecal Contamination In Pitcher Pump Systems And Measurement Alternatives, Meghan Wahlstrom May 2014

Drinking Water In The Developing World: Sources Of Fecal Contamination In Pitcher Pump Systems And Measurement Alternatives, Meghan Wahlstrom

USF Tampa Graduate Theses and Dissertations

It has been reported that globally we have achieved Millennium Development Goal (MDG) Target 7C, to halve the proportion of the population without access to safe drinking water; however, there is a major flaw with this statement. While Target 7C calls for access to `safe' drinking water, what is actually being measured and reported is access to an `improved' water source. The World Health Organization (WHO) maintains that they must use this proxy measure because the methods for water quality testing are too expensive and logistically complicated, but by doing so, they may be over reporting safe water coverage.

This …


Troubled Waters: Georgia, Florida And Alabama's Conflict Over The Waters Of The Acf River Basin, Johnny King Alaziz Wong May 2014

Troubled Waters: Georgia, Florida And Alabama's Conflict Over The Waters Of The Acf River Basin, Johnny King Alaziz Wong

USF Tampa Graduate Theses and Dissertations

Since 1989, the co-riparian States of Georgia, Florida and Alabama have been locked in an overt and institutionalized conflict to secure access to the waters of the Apalachicola-Chattahoochee-Flint (ACF) River Basin. In 1997, in an effort to end this interstate conflict which had earned the reputation as the longest water conflict in U.S. history, public officials at the federal and state scales agreed to suspend all pending litigation against one another and concurrently deployed a dispute resolution mechanism, known as `compact negotiations,' in the hope of equitably allocating the waters of the ACF Basin. Despite proclamations by public officials, exclaiming …


An Assessment Of The Emas Pump And Its Potential For Use In Household Water Systems In Uganda, Jacob Daniel Carpenter May 2014

An Assessment Of The Emas Pump And Its Potential For Use In Household Water Systems In Uganda, Jacob Daniel Carpenter

USF Tampa Graduate Theses and Dissertations

Rural improved water supply coverage in Uganda has stagnated around 64% for a number of years and at this point more than 10 million rural people do not have access to an improved drinking water source. It has been recognized that progress toward improved water supply coverage and increased service levels may be gained through Government and nongovernmental organization (NGO) support of private investment in household and shared water supplies, commonly known as Self-supply. Self-supply can be promoted by introducing and building local capacity in appropriate and affordable water supply technologies such as hand-dug wells, manually drilled boreholes, low-cost pumps, …


Hail Formation In Florida, Matthew Stanley May 2014

Hail Formation In Florida, Matthew Stanley

USF Tampa Graduate Theses and Dissertations

ABSTRACT

Hail poses a substantial threat to life and property in the state of Florida. These losses could be minimized through better understanding of the relationships between atmospheric variables that impact hail formation in Florida. Improving hail forecasting in Florida requires analyzing a number of meteorological parameters and synoptic data related to hail formation.

NOAA archive data was retrieved to create a database that was used to categorize text files of hail days. The text files were entered into the National Oceanic and Atmospheric Administration Earth System Research Laboratory website to create National Centers for Environmental Prediction/National Center for Atmospheric …


Assessing The Impacts Of Unrestricted Pesticide Use In Small-Scale Agriculture On Water Quality And Associated Human Health And Ecological Implications In An Indigenous Village In Rural Panam[Aacute], Sarah Louise Watson May 2014

Assessing The Impacts Of Unrestricted Pesticide Use In Small-Scale Agriculture On Water Quality And Associated Human Health And Ecological Implications In An Indigenous Village In Rural Panam[Aacute], Sarah Louise Watson

USF Tampa Graduate Theses and Dissertations

In 2014, the global pesticide industry's projected worth is $52 billion and by 2020, the developing world will make up one-third of the world's chemical production and consumption. Pesticides can have unintended negative consequences for human health and the environment, especially in the developing world where regulations are loose or nonexistent. One country with unrestricted use of pesticides is Panam[aacute], especially in Santa Rosa de Cucunatí. In this indigenous village, small-scale farmers and ranchers spray paraquat, glyphosate, picloram, and 2,4-D at higher elevations than the spring water source of a gravity-fed water system, the river, and the village. The objective …