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Description
For the past 30 years wildlife biologists have debated the need of pronghorn antelope (Antilocapra americana) to drink freestanding water (free water). Some have suggested that pronghorn may feed at night to increase preformed water (plant moisture) intake, thus decreasing their dependence on free water. Pronghorn diet composition and nutrient

For the past 30 years wildlife biologists have debated the need of pronghorn antelope (Antilocapra americana) to drink freestanding water (free water). Some have suggested that pronghorn may feed at night to increase preformed water (plant moisture) intake, thus decreasing their dependence on free water. Pronghorn diet composition and nutrient intake is integral to understanding water available to pronghorn through preformed and metabolic sources. The dual purpose of this study was to determine plant composition of pronghorn diets, and to examine whether night feeding provides a water allocation advantage by testing for differences between day and night and modeling free water requirements during biologically critical seasons and years of different precipitation. I determined species composition, selected nutrients, and moisture content of American pronghorn diets on Perry Mesa, Arizona in March, May, June and August of 2008 and 2009. I used microhistological analysis of fecal samples to determine percent plant composition of pronghorn diets. I used forage samples to evaluate the nutrient composition of those diets for moisture, crude protein and structural carbohydrates, and to calculate metabolic water. I used calculations proposed by Fox et al. (2000) to model free water requirements and modified the equations to reflect increased requirements for lactation. Diet analysis revealed that pronghorn used between 67% and 99% forbs and suggested fair range conditions. Preformed water was not significantly different between night and day. Night feeding appeared to be of marginal advantage, providing an average potential 9% preformed water increase in 2008, and 3% in 2009. The model indicated that neither male nor female pronghorn could meet their water requirements from preformed and metabolic water during any time period, season or year. The average free water requirements for females ranged from 0.67 L/animal/day (SE 0.06) in March, 2008 to 3.12 L/animal/day (SE 0.02) in June, 2009. The model showed that American pronghorn on Perry Mesa require access to free water during biological stress periods.
ContributorsTluczek, Melanie (Author) / Miller, William H. (Thesis advisor) / Brown, David E. (Committee member) / Steele, Kelly (Committee member) / Arizona State University (Publisher)
Created2012
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Description
Is it possible to treat the mouth as a natural environment, and determine new methods to keep the microbiome in check? The need for biodiversity in health may suggest that every species carries out a specific function that is required to maintain equilibrium and homeostasis within the oral cavity. Furthermore,

Is it possible to treat the mouth as a natural environment, and determine new methods to keep the microbiome in check? The need for biodiversity in health may suggest that every species carries out a specific function that is required to maintain equilibrium and homeostasis within the oral cavity. Furthermore, the relationship between the microbiome and its host is mutually beneficial because the host is providing microbes with an environment in which they can flourish and, in turn, keep their host healthy. Reviewing examples of larger scale environmental shifts could provide a window by which scientists can make hypotheses. Certain medications and healthcare treatments have been proven to cause xerostomia. This disorder is characterized by a dry mouth, and known to be associated with a change in the composition, and reduction, of saliva. Two case studies performed by Bardow et al, and Leal et al, tested and studied the relationships of certain medications and confirmed their side effects on the salivary glands [2,3]. Their results confirmed a relationship between specific medicines, and the correlating complaints of xerostomia. In addition, Vissink et al conducted case studies that helped to further identify how radiotherapy causes hyposalivation of the salivary glands [4]. Specifically patients that have been diagnosed with oral cancer, and are treated by radiotherapy, have been diagnosed with xerostomia. As stated prior, studies have shown that patients having an ecologically balanced and diverse microbiome tend to have healthier mouths. The oral cavity is like any biome, consisting of commensalism within itself and mutualism with its host. Due to the decreased salivary output, caused by xerostomia, increased parasitic bacteria build up within the oral cavity thus causing dental disease. Every human body contains a personalized microbiome that is essential to maintaining health but capable of eliciting disease. The Human Oral Microbiomics Database (HOMD) is a set of reference 16S rRNA gene sequences. These are then used to define individual human oral taxa. By conducting metagenomic experiments at the molecular and cellular level, scientists can identify and label micro species that inhabit the mouth during parasitic outbreaks or a shifting of the microbiome. Because the HOMD is incomplete, so is our ability to cure, or prevent, oral disease. The purpose of the thesis is to research what is known about xerostomia and its effects on the complex microbiome of the oral cavity. It is important that researchers determine whether this particular perspective is worth considering. In addition, the goal is to create novel experiments for treatment and prevention of dental diseases.
ContributorsHalcomb, Michael Jordan (Author) / Chen, Qiang (Thesis director) / Steele, Kelly (Committee member) / Barrett, The Honors College (Contributor) / College of Letters and Sciences (Contributor)
Created2015-05
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Description
The objective of this research was to predict the persistence of potential future contaminants in indirect potable reuse systems. In order to accurately estimate the fates of future contaminants in indirect potable reuse systems, results describing persistence from EPI Suite were modified to include sorption and oxidation. The target future

The objective of this research was to predict the persistence of potential future contaminants in indirect potable reuse systems. In order to accurately estimate the fates of future contaminants in indirect potable reuse systems, results describing persistence from EPI Suite were modified to include sorption and oxidation. The target future contaminants studied were the approximately 2000 pharmaceuticals currently undergoing testing by United States Food and Drug Administration (US FDA). Specific organic substances such as analgesics, antibiotics, and pesticides were used to verify the predicted half-lives by comparing with reported values in the literature. During sub-surface transport, an important component of indirect potable reuse systems, the effects of sorption and oxidation are important mechanisms. These mechanisms are not considered by the quantitative structure activity relationship (QSAR) model predictions for half-lives from EPI Suite. Modifying the predictions from EPI Suite to include the effects of sorption and oxidation greatly improved the accuracy of predictions in the sub-surface environment. During validation, the error was reduced by over 50% when the predictions were modified to include sorption and oxidation. Molecular weight (MW) is an important criteria for estimating the persistence of chemicals in the sub-surface environment. EPI Suite predicts that high MW compounds are persistent since the QSAR model assumes steric hindrances will prevent transformations. Therefore, results from EPI Suite can be very misleading for high MW compounds. Persistence was affected by the total number of halogen atoms in chemicals more than the sum of N-heterocyclic aromatics in chemicals. Most contaminants (over 90%) were non-persistent in the sub-surface environment suggesting that the target future drugs do not pose a significant risk to potable reuse systems. Another important finding is that the percentage of compounds produced from the biotechnology industry is increasing rapidly and should dominate the future production of pharmaceuticals. In turn, pharmaceuticals should become less persistent in the future. An evaluation of indirect potable reuse systems that use reverse osmosis (RO) for potential rejection of the target contaminants was performed by statistical analysis. Most target compounds (over 95%) can be removed by RO based on size rejection and other removal mechanisms.
ContributorsLim, Seung (Author) / Fox, Peter (Thesis advisor) / Abbaszadegan, Morteza (Committee member) / Halden, Rolf (Committee member) / Arizona State University (Publisher)
Created2011
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Description
The deterioration of drinking-water quality within distribution systems is a serious cause for concern. Extensive water-quality deterioration often results in violations against regulatory standards and has been linked to water-borne disease outbreaks. The causes for the deterioration of drinking water quality inside distribution systems are not yet fully

The deterioration of drinking-water quality within distribution systems is a serious cause for concern. Extensive water-quality deterioration often results in violations against regulatory standards and has been linked to water-borne disease outbreaks. The causes for the deterioration of drinking water quality inside distribution systems are not yet fully understood. Mathematical models are often used to analyze how different biological, chemical, and physical phenomena interact and cause water quality deterioration inside distribution systems. In this dissertation research I developed a mathematical model, the Expanded Comprehensive Disinfection and Water Quality (CDWQ-E) model, to track water quality changes in chloraminated water. I then applied CDWQ-E to forecast water quality deterioration trends and the ability of Naegleria fowleri (N.fowleri), a protozoan pathogen, to thrive within drinking-water distribution systems. When used to assess the efficacy of substrate limitation versus disinfection in controlling bacterial growth, CDWQ-E demonstrated that bacterial growth is more effectively controlled by lowering substrate loading into distribution systems than by adding residual disinfectants. High substrate concentrations supported extensive bacterial growth even in the presence of high levels of chloramine. Model results also showed that chloramine decay and oxidation of organic matter increase the pool of available ammonia, and thus have potential to advance nitrification within distribution systems. Without exception, trends predicted by CDWQ-E matched trends observed from experimental studies. When CDWQ-E was used to evaluate the ability N. fowleri to survive in finished drinking water, the model predicted that N. fowleri can survive for extended periods of time in distribution systems. Model results also showed that N. fowleri growth depends on the availability of high bacterial densities in the 105 CFU/mL range. Since HPC levels this high are rarely reported in bulk water, it is clear that in distribution systems biofilms are the prime reservoirs N. fowleri because of their high bacterial densities. Controlled laboratory experiments also showed that drinking water can be a source of N. fowleri, and the main reservoir appeared to be biofilms dominated by bacteria. When introduced to pipe-loops N. fowleri successfully attached to biofilms and survived for 5 months.
ContributorsBiyela, Precious Thabisile (Author) / Rittmann, Bruce E. (Thesis advisor) / Abbaszadegan, Morteza (Committee member) / Butler, Caitlyn (Committee member) / Arizona State University (Publisher)
Created2010
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Description
The impact of physical/chemical properties of gray water on microbial inactivation in gray water using chlorine was investigated through creating artificial gray water in lab, varying specific components, and then measuring microbial inactivation. Gray water was made through taking autoclaved nanopure water, and increasing the concentration of surfacants, the turbidity,

The impact of physical/chemical properties of gray water on microbial inactivation in gray water using chlorine was investigated through creating artificial gray water in lab, varying specific components, and then measuring microbial inactivation. Gray water was made through taking autoclaved nanopure water, and increasing the concentration of surfacants, the turbidity, the concentration of organic content, and spiking E. coli grown in tryptic soy broth (TSB); chlorine was introduced using Clorox Disinfecting Bleach2. Bacteria was detected using tryptic soy agar (TSA), and E. coli was specifically detected using the selective media, brilliance. The log inactivation of bacteria detected using TSA was shown to be inversely related to the turbidity of the solution. Complete inactivation of E. coli concentrations between 104-105 CFU/100 ml in gray water with turbidities between 10-100 NTU, 0.1-0.5 mg/L of humic acid, and 0.1 ml of Dawn Ultra, was shown to occur, as detected by brilliance, at chlorine concentrations of 1-2 mg/L within 30 seconds. These result in concentration time (CT) values between 0.5-1 mg/L·min. Under the same gray water conditions, and an E. coli concentration of 104 CFU/100 ml and a chlorine concentration of 0.01 mg/L, complete inactivation was shown to occur in all trials within two minutes. These result in CT values ranging from 0.005 to 0.02. The turbidity and humic acid concentration were shown to be inversely related to the log inactivation and directly related to the CT value. This study shows that chlorination is a valid method of treatment of gray water for certain irrigation reuses.
ContributorsGreenberg, Samuel Gabe (Author) / Abbaszadegan, Morteza (Thesis director) / Schoepf, Jared (Committee member) / Alum, Absar (Committee member) / Chemical Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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Description
The purpose of this study was to determine the applicability of fluorescent microspheres as a surrogate to measure the removal of Cryptosporidium oocysts through the coagulation, flocculation, sedimentation, and filtration steps of conventional water treatment. In order to maintain accuracy and applicability, a local water treatment facility was chosen as

The purpose of this study was to determine the applicability of fluorescent microspheres as a surrogate to measure the removal of Cryptosporidium oocysts through the coagulation, flocculation, sedimentation, and filtration steps of conventional water treatment. In order to maintain accuracy and applicability, a local water treatment facility was chosen as the system to model. The city of Chandler Arizona utilizes conventional treatment methodologies to remove pathogens from municipal drinking water and thus the water, coagulant, polymer, and doses concentrations were sourced directly from the plant. Jar testing was performed on four combinations of coagulant, polymer, and fluorescent microsphere to determine if the log removal was similar to that of Cryptosporidium oocysts.

Complications with the material properties of the microspheres arose during testing that ultimately yielded unfavorable but conclusive results. Log removal of microspheres did not increase with added coagulant in the predicted manner, though the beads were seen aggregating, the low density of the particles made the sedimentation step inefficient. This result can be explained by the low density of the microspheres as well as the potential presence of residual coagulant present in the system. Given the unfavorable properties of the beads, they do not appear to be a suitable candidate for the surrogacy of Cryptosporidium oocysts in conventional drinking water treatment. The beads in their current state are not an adequate surrogate; however, future testing has been outlined to modify the experiment in such a way that the microspheres should behave like oocysts in terms of physical transportation.
ContributorsLinks, Alexander Glenn (Author) / Abbaszadegan, Morteza (Thesis advisor) / Alum, Absar (Committee member) / Fox, Peter (Committee member) / Arizona State University (Publisher)
Created2015
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Description
The need for rapid, specific and sensitive assays that provide a detection of bacterial indicators are important for monitoring water quality. Rapid detection using biosensor is a novel approach for microbiological testing applications. Besides, validation of rapid methods is an obstacle in adoption of such new bio-sensing technologies.

The need for rapid, specific and sensitive assays that provide a detection of bacterial indicators are important for monitoring water quality. Rapid detection using biosensor is a novel approach for microbiological testing applications. Besides, validation of rapid methods is an obstacle in adoption of such new bio-sensing technologies. In this study, the strategy developed is based on using the compound 4-methylumbelliferyl glucuronide (MUG), which is hydrolyzed rapidly by the action of E. coli β-D-glucuronidase (GUD) enzyme to yield a fluorogenic product that can be quantified and directly related to the number of E. coli cells present in water samples. The detection time required for the biosensor response ranged from 30 to 120 minutes, depending on the number of bacteria. The specificity of the MUG based biosensor platform assay for the detection of E. coli was examined by pure cultures of non-target bacterial genera and also non-target substrates. GUD activity was found to be specific for E. coli and no such enzymatic activity was detected in other species. Moreover, the sensitivity of rapid enzymatic assays was investigated and repeatedly determined to be less than 10 E. coli cells per reaction vial concentrated from 100 mL of water samples. The applicability of the method was tested by performing fluorescence assays under pure and mixed bacterial flora in environmental samples. In addition, the procedural QA/QC for routine monitoring of drinking water samples have been validated by comparing the performance of the biosensor platform for the detection of E. coli and culture-based standard techniques such as Membrane Filtration (MF). The results of this study indicated that the fluorescence signals generated in samples using specific substrate molecules can be utilized to develop a bio-sensing platform for the detection of E. coli in drinking water. The procedural QA/QC of the biosensor will provide both industry and regulatory authorities a useful tool for near real-time monitoring of E. coli in drinking water samples. Furthermore, this system can be applied independently or in conjunction with other methods as a part of an array of biochemical assays in order to reliably detect E. coli in water.
ContributorsHesari, Nikou (Author) / Abbaszadegan, Morteza (Thesis advisor) / Alum, Absar (Committee member) / Fox, Peter (Committee member) / Stout, Valerie (Committee member) / Arizona State University (Publisher)
Created2015
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Description
The National Research Council 2011 report lists quantifying the extent of de facto (or unplanned) potable reuse in the U.S. as the top research need associated with assessing the potential for expanding the nations water supply through reuse of municipal wastewater. Efforts to identify the significance and potential health impacts

The National Research Council 2011 report lists quantifying the extent of de facto (or unplanned) potable reuse in the U.S. as the top research need associated with assessing the potential for expanding the nations water supply through reuse of municipal wastewater. Efforts to identify the significance and potential health impacts of de facto water reuse are impeded by out dated information regarding the contribution of municipal wastewater effluent to potable water supplies. This project aims to answer this research need. The overall goal of the this project is to quantify the extent of de facto reuse by developing a model that estimates the amount of wastewater effluent that is present within drinking water treatment plants; and to use the model in conjunction with a survey to help assess public perceptions. The four-step approach to accomplish this goal includes: (1) creating a GIS-based model coupled with Python programming; (2) validating the model with field studies by analyzing sucralose as a wastewater tracer; (3) estimating the percentage of wastewater in raw drinking water sources under varying streamflow conditions; (4) and assessing through a social survey the perceptions of the general public relating to acceptance and occurrence of de facto reuse. The resulting De Facto Reuse in our Nations Consumable Supply (DRINCS) Model, estimates that treated municipal wastewater is present at nearly 50% of drinking water treatment plant intake sites serving greater than 10,000 people (N=2,056). Contrary to the high frequency of occurrence, the magnitude of occurrence is relatively low with 50% of impacted intakes yielding less than 1% de facto reuse under average streamflow conditions. Model estimates increase under low flow conditions (modeled by Q95), in several cases treated wastewater makes up 100% of the water supply. De facto reuse occurs at levels that surpass what is publically perceived in the three cities of Atlanta, GA, Philadelphia, PA, and Phoenix, AZ. Respondents with knowledge of de facto reuse occurrence are 10 times more likely to have a high acceptance (greater than 75%) of treated wastewater at their home tap.
ContributorsRice, Jacelyn (Author) / Westerhoff, Paul (Thesis advisor) / Abbaszadegan, Morteza (Committee member) / Vivoni, Enrique (Committee member) / Wutich, Amber (Committee member) / Arizona State University (Publisher)
Created2014
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Description
Microalgae represent a potential sustainable alternative for the enhancement and protection of agricultural crops. The dry biomass and cellular extracts of Scenedesmus dimorphus were applied as a biofertilizer, a foliar spray, and a seed primer to evaluate seed germination, plant growth, and crop yield of Roma tomato plants. The dry

Microalgae represent a potential sustainable alternative for the enhancement and protection of agricultural crops. The dry biomass and cellular extracts of Scenedesmus dimorphus were applied as a biofertilizer, a foliar spray, and a seed primer to evaluate seed germination, plant growth, and crop yield of Roma tomato plants. The dry biomass was applied as a biofertilizer at 50 g and 100 g per plant, to evaluate its effects on plant development and crop yield. Biofertilizer treatments enhanced plant growth and led to greater crop (fruit) production. Timing of biofertilizer application proved to be of importance - earlier 50 g biofertilizer application resulted in greater plant growth. Scenedesmus dimorphus culture, growth medium, and different concentrations (1%, 5%, 10%, 25%, 50%, 75%, 100%) of aqueous cell extracts were used as seed primers to determine effects on germination. Seeds treated with Scenedesmus dimorphus culture and with extract concentrations higher than 50 % (0.75 g ml-1) triggered faster germination - 2 days earlier than the control group. Extract foliar sprays of 50 ml and 100 ml, were obtained and applied to tomato plants at various extract concentrations (10%, 25%, 50%, 75% and 100%). Plant height, flower development and number of branches were significantly enhanced with 50 % (7.5 g ml-1) extracts. Higher concentration sprays led to a decrease in growth. The extracts were further screened to assess potential antimicrobial activity against the bacterium Escherichia coli ATCC 25922, the fungi Candida albicans ATCC 90028 and Aspergillus brasiliensis ATCC 16404. No antimicrobial activity was observed from the microalga extracts on the selected microorganisms.
ContributorsGarcia-Gonzalez, Jesus (Author) / Sommerfeld, Milton (Thesis advisor) / Steele, Kelly (Committee member) / Henderson, Mark (Committee member) / Arizona State University (Publisher)
Created2014
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Description
Granular activated carbon (GAC) filters are final polishing step in the drinking water treatment systems for removal of dissolved organic carbon fractions. Generally filters are colonized by bacterial communities and their activity reduces biodegradable solutes allowing partial regeneration of GAC's adsorptive capacity. When the bacteria pass into the filtrate due

Granular activated carbon (GAC) filters are final polishing step in the drinking water treatment systems for removal of dissolved organic carbon fractions. Generally filters are colonized by bacterial communities and their activity reduces biodegradable solutes allowing partial regeneration of GAC's adsorptive capacity. When the bacteria pass into the filtrate due to increased growth, microbiological quality of drinking water is compromised and regrowth in the distribution system occurs. Bacteria attached to carbon particles as biofilms or in conjugation with other bacteria were observed to be highly resistant to post filtration microbial mitigation techniques. Some of these bacteria were identified as pathogenic.

This study focuses on one such pathogen Legionella pneumophila which is resistant to environmental stressors and treatment conditions. It is also responsible for Legionnaires' disease outbreak through drinking water thus attracting attention of regulatory agencies. The work assessed the attachment and colonization of Legionella and heterotrophic bacteria in lab scale GAC media column filters. Quantification of Legionella and HPC in the influent, effluent, column's biofilms and on the GAC particles was performed over time using fluorescent microscopy and culture based techniques.

The results indicated gradual increase in the colonization of the GAC particles with HPC bacteria. Initially high number of Legionella cells were detected in the column effluent and were not detected on GAC suggesting low attachment of the cells to the particles potentially due to lack of any previous biofilms. With the initial colonization of the filter media by other bacteria the number of Legionella cells on the GAC particles and biofilms also increased. Presence of Legionella was confirmed in all the samples collected from the columns spiked with Legionella. Significant increase in the Legionella was observed in column's inner surface biofilm (0.25 logs up to 0.52 logs) and on GAC particles (0.42 logs up to 0.63 logs) after 2 months. Legionella and HPC attached to column's biofilm were higher than that on GAC particles indicating the strong association with biofilms. The bacterial concentration slowly increased in the effluent. This may be due to column's wall effect decreasing filter efficiency, possible exhaustion of GAC capacity over time and potential bacterial growth.
ContributorsSharma, Harsha (Author) / Abbaszadegan, Morteza (Thesis advisor) / Alum, Absar (Committee member) / Fox, Peter (Committee member) / Arizona State University (Publisher)
Created2014