Master of Science in Engineering, University of Akron, 2023, Chemical Engineering

Algal cyanobacteria can produce cyanotoxins in the surface water. The rise in cyanotoxins occurrence and concentration threatens animals and humans, making them a global environmental challenge. Powdered activated carbon (PAC) is a non-reactive and cost-effective option for the adsorption of cyanotoxins. The extent of adsorption is influenced by the properties of PAC, toxins, and surface water. This project focused on the removal of varying concentrations of microcystin-LR (MC-LR, 0.3, 1.6, and 20 μg/L) and saxitoxin (STX, 0.3 and 1.6 μg/L) with three different PAC sources. Experiments were performed with distilled water (pH 6 and 9) and natural water (pH 6, 8, and 9) when MC-LR and STX were present alone and simultaneously. Mixing rates of drinking water plant were scaled down to lab scale to replicate the rapid mix-flocculation by maintaining the same velocity gradient using a gang mixer. Additional tests were performed to find PAC's point of zero charge (pHPZC) to determine its overall surface charge variation with pH, which could affect adsorption based on cyanotoxin's charge. Source of PAC impacted removal of toxins. For instance, the wood-lignite-based PAC from CarbPure (CP) adsorbed more MC-LR than the bituminous coal-based PAC purchased from Calgon Carbon (CC) (p<0.05). Depending on the initial concentration, CP adsorbed 49-87% MC-LR in distilled water and 60-84% in raw water. CC only adsorbed 20-60% MC-LR from distilled water and 11-21% from raw water. In raw water across all pH and concentration combinations, STX removal was 16-80% with CP and 31-46% with CC. An experiment performed on 0.3 μg/L STX in distilled water with an additional PAC, Aquasorb (AS), had a removal trend of CP > AS > CC. The presence of multiple sources (AS and CP) may have enhanced adsorption. CP adsorbed (14-77%) more STX in distilled water than CC (21-49%) and AS (16-68%). When toxins were present simultaneously, CP effectively removed 48-72% MC-LR and 30-66% STX, depending upon the (open full item for complete abstract)

Committee: BI-MIN ZHANG NEWBY (Committee Member); LU-KWANG JU (Committee Member); TERESA CUTRIGHT (Advisor) Subjects: Chemical Engineering; Civil Engineering; Environmental Engineering

MA, Kent State University, 2023, College of Arts and Sciences / Department of Psychological Sciences

The increased demands that arise with dementia progression can make caregiving challenging, leading to an onset of burden in the caregiver. Although burden is often associated with caregiving, the role of the caregiver is linked to beneficial outcomes as well. Because individuals who report many positive aspects of caregiving tend to exhibit lower burden relative to those reporting few positive aspects of caregiving, caregiver burden and positive aspects of caregiving are often viewed as mutually exclusive constructs. The present study is a retrospective review of medical records from an outpatient memory clinic, with the goals of better understanding whether and how these constructs coexist within the individual caregiver and exploring potential contributors to caregiver profiles that emerge. A total of 225 patient-caregiver dyads were included in analyses. Results suggested a three-cluster solution with a highly burdened group, a group with low-moderate burden and positive experiences, and a group with high positive experiences. Presence of greater neuropsychiatric symptoms predicted assignment to the higher burden cluster, and greater care recipient dependence predicted assignment to the cluster with higher positive experiences. Future research should investigate other potential contributors to the experience of burden and positive aspects of caregiving.

Committee: Mary Beth Spitznagel (Advisor) Subjects: Clinical Psychology

Master of Science in Engineering, University of Akron, 2022, Civil Engineering

Cyanotoxins produced from cyanobacteria dominated harmful algal blooms (cHABs) are on the rise. This increase in toxins poses a threat to ecosystems as well as drinking water systems. This thesis evaluated the treatment of Anatoxin (ATX) and Saxitoxin (STX) when alone or with Microcystin (MC) using conditions of the Alliance drinking water treatment plant. The two treatments of focus were powdered activated carbon (PAC) added during the flocculation phase, which was evaluated in distilled (DI) water and raw source water, and chlorination in the disinfection phase evaluated in post-filtration water. The impact of pH was considered for both treatments. The impact of cyanobacteria cells in the PAC treatment was also assessed. STX showed removal of up to 81% in DI water, this best condition was achieved for the pH of 8 and 1.6 μg/L. The same trend was observed in raw water with a removal of up to 79% when STX was alone at pH 9. MC showed no impact on STX removal since removals were also in the 70-78% range (p>0.05). For ATX, the removal in DI water was minimal with the highest being 35% at pH 6 at a concentration of 20 μg/L. In general, a lower pH showed higher removal. In raw water at the same concentration, the removal went up to 80%. pH changes did not seem to have an impact on the removal. The addition of a higher concentration of MC seemed to improve the removal of ATX, this could be due to the charges of each of the toxins. The addition of cells did inhibit the removal of ATX, but not of MC. During chlorine experiments, STX had higher removals at higher pH levels. The highest removal was 57% at pH 9 with a concentration of 0.3 μg/L and MC concentration of 1.6. This corroborated that a higher concentration of MC led to higher removal. Only one ATX experiment was done since it had been shown before to not be very effective. ATX was removed by 38% at pH 6. Lastly, a concurrent study determined removal efficiencies for PAC and chlorine for the City of Akron, O (open full item for complete abstract)

Committee: Teresa Cutright (Advisor); Richard Einsporn (Committee Member); Nariman Mahabadi (Committee Member) Subjects: Civil Engineering; Environmental Engineering; Water Resource Management

Doctor of Philosophy, The Ohio State University, 2021, Computer Science and Engineering

Differential privacy has become a widely accepted data privacy model because of the strong formal guarantee it offers, namely no individual's data has a significant impact on the outcome of analyses on the data set. Unfortunately, this strict guarantee leads to fundamental limitations pertaining to the utility of different machine learning algorithms. These limitations manifest in various problem settings. For instance, learning simple classes of functions (e.g. one-dimensional thresholds over R) is impossible under differential privacy even though it can be easily learned without privacy constraints. As another example, the resulting error in privately solving fundamental problems such as stochastic convex optimization (SCO) or empirical risk minimization (ERM) is known to incur a necessary dependence on the dimension of the problem, which limits the applicability of such private algorithms in practical scenarios where the dimension is often very large. The goal of this dissertation is to tackle some of these fundamental limitations. To circumvent these challenges, we pursue two directions: (1) relaxing the model of differentially private learning, and (2) exploiting the geometry of the learning problem. In the first direction, the goal is to exploit a limited amount of public data to achieve substantial gains in accuracy (or, equivalently savings in sample complexity) of differentially private algorithms. In particular, We study the problem of differentially private release of classification queries. In this problem, the algorithm is given a private training dataset drawn from some unknown distribution and a stream of classification queries given by a sequence unlabeled feature vectors. Here, the feature-vectors defining the set of queries are assumed to be public (i.e., they do not involve any privacy constraints), and drawn from the same distribution as the feature vectors of the private dataset. We formally study this problem in the agnostic probab (open full item for complete abstract)

Committee: Raef Bassily (Advisor); Atanas Rountev (Committee Member); Wei-Lun Chao (Committee Member) Subjects: Computer Science

Doctor of Philosophy, University of Akron, 2020, Civil Engineering

Drinking water treatment is a combination of physical and chemical processes to improve the quality of the finished water (i.e. treated water). In addition to particle removal, treatment plants must reduce the dissolved organic matter (DOM) concentration. DOM must be reduced because it contains disinfection byproduct (DBP) precursors and creates disinfectant demand in the distribution system. Fluorescence measurements, including those used in this study, offer a rapid but effective technique to measure and characterize DOM in both the source and treated water, as well as assess powdered activated carbon (PAC) performance. PAC is a widely used material for DOM and trace compound removal. This research focused on two different aspects using fluorescence metrics: (1) incorporating them into models for treated water quality prediction and (2) to assess PAC performance and competitive adsorption from DOM. The first part of this study focused on a modeling approach of treated water quality data collected by former coworkers1,2 obtained from a water treatment plant (WTP) in Ohio. The dataset includes over 800 fluorescence inplant measurements from December 2009 to December 2012. Reduction of disinfection by-product (DBP) formation potential was studied based on UV, dissolved organic matter (DOM) and fluorescence-derived metrics. Parameters measuring water quality including fluorescence intensity were collected before and after coagulation and the DBP formation potential (DBPFP) was also measured.A comparative study including different model functions of Gaussian, Neural Networks, Linear Regression, Simple linear regression, SMOreg, Bagging, M5Rules and trees was performed. The purpose of this work was to examine fluorescence excitation emission matrix spectroscopy (EEMs) measures as predictors and compare them with more general DOM measurement methods (DOC and UV254). These models could then be used to monitor, model, and manage DBPFP during water (open full item for complete abstract)

Committee: Christopher Miller Dr. (Advisor); Stephen Duirk Dr. (Committee Member); Roke David Dr. (Committee Member); Qindan Huang Dr. (Committee Member); Einsporn Richard Dr. (Committee Member) Subjects: Environmental Engineering; Environmental Science

Master of Science in Engineering, University of Akron, 2020, Civil Engineering

Excess phosphorous in water ways is known to be a cause of harmful algal blooms. These blooms have caused problems with water aesthetics and recreational use. Water Treatment Residual (WTR) has been shown to have an affinity for phosphorous. Since WTR is a bi-product of the drinking water treatment process it has the potential of being a low-cost alternative to remove excess phosphorous from water ways, potentially preventing harmful algal blooms. A previous study proved there was a beneficial reuse for WTR produced at the Akron Water Treatment plant for binding excess phosphorous. This research thesis looked further into Akron Water Treatment Plants WTR, to see if baking could increase its phosphorous adsorption capacity. Initial 24-hour sorption studies determined optimal baking temperatures of 175°C for Al-WTR (ce = 0.31 mg/L, qe = 117.21) and 150°C for PAC-WTR (ce = 0.20 mg/L, qe = 120.00). Isotherm studies for baked Al-WTR (175°C) and PAC-WTR (150°C) found that there was a net desorption of phosphorous when in distilled background solution. A statistical analysis across all experimental conditions determined that baked PAC-WTR (mean qe 11.00 mg/kg) performed significantly (ρ < 0.05) better than baked Al-WTR (mean qe 8.18 mg/kg). When the specific condition of the isotherm experiments were considered, baked PAC-WTR sorbed more PO4 (mean qe 36.64 mg/kg) (ρ < 0.05) when subjected to raw water at 20°C and static in conditions. Baked Al-WTR was the next best (mean qe 21.42 mg/kg) significantly (ρ < 0.05) in 5°C Static in raw water. Continuous flow column tests were also conducted to find the sorption maximum of the baked WTR, and to compare the adsorption capacity of As-Is WTR versus baked WTR conducted. Baked WTR was found to have an affinity for phosphorous with a sorption capacity of 7.91 mg-P/g-WTR for baked Al-WTR and 16.21 mg-P/kg-WTR. When compared to As-Is WTR, baked PAC WTR was the only material found to have a higher adsorption capacity by (open full item for complete abstract)

Committee: Teresa Cutright PhD (Advisor); Donald Ott PhD (Committee Member); Stephen Duirk PhD (Committee Member) Subjects: Civil Engineering; Engineering; Environmental Engineering; Environmental Science

Artium Baccalaureus (AB), Ohio University, 2014, French

Pendant que les communautes rurales se trouvent de plus en plus poussees vers l’urbanisation, les paysans francais s’accrochent a leurs proprietes et a leur heritage. L’agriculture mecanisee, alimentee par un haut taux d’investissement et des developpements technologiques, remplace le besoin du travail manuel a la campagne pendant que les methodes productivistes augment brusquement la reserve des produits agricoles aux niveaux excessifs, font baisser les prix, et saisissent la part de marche. Bien que les grandes corporations agroalimentaires en France soient mieux regulees que celles dans d’autres pays tels que les Etats-Unis, la legislation au niveau national et au niveau europeen favorisent les operations agricoles plus efficaces au depens des petites fermes traditionnelles. Cette these part en exploration des chances de reussite de redynamiser les communautes rurales durables en France, et les benefices atteignables si l’on soutient des methodes de culture traditionnelles et moins intensives. As rural communities find themselves continuously pushed towards urbanization, the French provincial-farmer class clings to its landholdings and its heritage. New investments in expensive farming equipment and techniques are replacing the need for manual labor in the countryside as productivist methods hike the supply of agricultural products to excessive levels, depress prices, and seize market share. While large food and agriculture corporations in France are more tightly regulated than they are in countries such as the United States, legislation at both the national and European levels have favored more efficient agricultural operations to the detriment of traditional small farms. This thesis explores the viability of reinvigorating sustainable rural communities in France and the benefits of supporting less-intensive, more traditional farming practices.

Committee: Lois Vines Dr. (Advisor) Subjects: Agricultural Economics; Agriculture; Business Costs; Conservation; Demographics; Economics; Environmental Economics; Environmental Health; Environmental Management; Environmental Studies; European Studies; Food Science; Modern History

PhD, University of Cincinnati, 2009, Medicine : Industrial Hygiene (Environmental Health)

Exposures to polycyclic aromatic hydrocarbons (PAHs) may cause lung and bladder cancer. Exposure monitoring programs have been used in the aluminum smelter industry for decades to decrease the risk of cancer from exposure to PAHs, while other industries such as the offshore industry has never been monitored. Biological monitoring of PAHs incorporates all routes of exposure. Measuring post-shift urinary 1-hydroxypyrene (1OHP), a metabolite of pyrene, is a surrogate for workers' daily PAH exposures, while DNA adducts detected in white blood cells or urothelial cells can reflect chronic exposures to PAHs. In the first study, we reviewed the scientific literature to identify changes over time in (1) 1OHP levels, (2) DNA-adduct levels, and (3) other contributing factors associated with 1OHP and DNA-adduct levels in the aluminum smelter industry. No trends were observed in 1OHP and DNA-adduct levels. This could be due to variable selection of study populations and poorly identified job tasks which prevent comparison of jobs across plants and times, unassessed worker exposure variability, and the impact of cumulative exposures. Inconsistent findings were also observed in the analysis of CYP1A1, GSTM1 and GSTP1 polymorphisms and their effect on biomarker levels. Future studies should be aimed at follow-up in workplaces where dermal and inhalation exposure interventions have been employed. In the second study, we explored the possibility of exposure to PAH derivatives in aluminum smelters such as fluorine-substituted PAHs (F-PAHs). Coal tar is used as an anode and cryolite (Na3AlF6) is the solvent in the electrochemical reaction in a smelter. The aim of this study was to determine whether F-PAHs were actually formed in aluminum smelters. Settled dust samples (n = 5) were extracted using established PAH extraction methods. Detection methods were reverse phase high performance liquid chromatography with photodiode array ultraviolet detection (HPLC/PDA), and gas chromatography (open full item for complete abstract)

Committee: Glenn Talaska PhD (Committee Chair); Paul Succop PhD (Committee Member); Mary Beth Genter PhD (Committee Member); James Mack PhD (Committee Member); Tania Carreon PhD (Committee Member) Subjects: Analytical Chemistry; Biostatistics; Chemical Engineering; Chemistry; Environmental Engineering; Environmental Science; Epidemiology; Health; Occupational Safety; Oncology; Organic Chemistry; Petroleum Production; Public Health; Toxicology

Doctor of Philosophy, The Ohio State University, 2009, Civil Engineering

The presence of cyanobacteria and associated cyanotoxins in surface water is of increasing concern. Microcystins are one of the most dangerous and commonly occurring classes of cyanotoxins. Ingestion of microcystin-LR can lead to liver damage and the promotion of liver tumors. Due to adverse health effects, the World Health Organization set a guideline level of 1 part per billion (ppb) for microcystin-LR in drinking water. However, current water treatment facilities may not specifically treat drinking water for microcystins. The overall goal of this research was to develop an advanced and effective process for the removal of microcystins from drinking water. To achieve this goal, powdered activated carbon (PAC), iron oxide nanoparticles, and ultrafiltration (UF) membranes were explored as promising treatment technologies. The use of ultrafiltration was investigated for the rejection of microcystin-LR from drinking water. Adsorption dominated rejection for most UF membranes, at least at early filtration times, while both size exclusion and adsorption were important in removing microcystin-LR by the tight thin-film membranes. The extent of membrane adsorption was generally related to membrane hydrophobicity. The application of ultrafiltration coupled with powdered activated carbon (PAC-UF) was also investigated. Of the two different PAC materials, wood-based activated carbon was more effective at removing microcystin-LR than coconut-based carbon due to greater mesopore volume. The PAC-UF system had the highest removal efficiency among the three processes (i.e., PAC adsorption, ultrafiltration, and PAC-UF) for both hydrophobic polyethersulfone (PES) and hydrophilic cellulose acetate (CA) membranes. When PAC was coupled to UF using PES membranes, greater removal of microcystin-LR occurred compared to when CA membranes were used, due to sorption of the toxin to the PES membrane surface. In further studies, Suwannee River Fulvic Acid (SRFA) was used to examine the effe (open full item for complete abstract)

Committee: Harold Walker (Advisor); Linda Weavers (Committee Member); John Lenhart (Committee Member); Yu-Ping Chin (Committee Member) Subjects: Chemical Engineering; Chemistry; Civil Engineering; Engineering; Environmental Engineering; Environmental Science; Geochemistry

Master of Science, Miami University, 2005, Physics

The main focus of this research is to show, through the use of perturbed angular correlation spectroscopy (PAC), that a displacive phase change occurs in the mineral zirconium silicate, ZrSiO4, which is related to the purity of the sample. This phase change is known to exist in pure naturally occurring zircon, which has low levels of impurities and radiation damage. This subtle phase change occurs in the mineral occurs around the annealing temperature of 800°C. In order to obtain an extremely pure crystal, a synthetic ZrSiO4 crystal is made. Once the phase change is shown to exist in the synthetic ZrSiO4, the theory that the phase change is dependent upon the purity of the sample will be reconfirmed by performing the same experiments using a synthetic sample of hafnon, HfSiO4. Zircon and hafnon share many of the same physical and chemical properties and should behave the same under the performed tests. The observation of the phase change is performed by using the measurable electric field gradient parameters obtained from PAC spectroscopy. X-ray diffraction (XRD) spectroscopy is used after the production of the synthetic samples to determine the relative purity of both samples. Both samples were run under the same conditions and both do exhibit the phase change at a temperature shortly following the annealing temperature. As shown in this work these phase changes are seen in the pure synthetic samples, and as shown in previous work, are only present in naturally occurring samples that have low levels of impurities.

Committee: Herbert Jaeger (Advisor) Subjects:

Master of Science, Miami University, 2005, Physics

The mineral zirconium silicate, ZrSiO4, or zircon is of interest due to its low coefficient of thermal expansion. Metamict zircon heated above 800 °C undergoes a structural displacive phase transition. These properties are favorable for applications in the foundry industry as form liners, wave guide materials, and actinide-bearing structures for nuclear waste containment. Perturbed angular correlation (PAC) techniques are used to study the short range order of any phase transition at a Zr-site. PAC measurements of the electric field gradient (EFG) were obtained for two samples from room temperature to 1100 °C. Samples for the PAC experiments were prepared from commercial materials obtained from Aldrich and Alfa Aesar. The primary EFG parameters for both samples were consistent with previously published data. The quadrupole interaction frequency decreased linearly with increasing temperature and the asymmetry values were near zero. Uncharacteristic observations in the anisotropy may be resultant of an after effect condition. Evidence of a displacive phase transition in the temperature range of 800 °C could not be confirmed.

Committee: Herbert Jaeger (Advisor) Subjects:

Doctor of Philosophy, Miami University, 2013, Chemistry and Biochemistry

The goal of the research performed for this thesis was to further develop and evaluate vibrational spectroscopic techniques, specifically infrared and Raman spectroscopies, in challenging sampling situations. Some experiments focused on analyzing samples with techniques that had limited to no previous research while others focused on modifying current techniques providing alternate and possibly improved methods of detection and analysis. Chapter 1 provides background into the fundamentals of infrared and Raman spectroscopy and briefly covers sampling techniques available. Chapter 2 demonstrates that a commercial Raman microscope can be externally modified to sample using attenuated total internal reflectance (ATR). This modification allowed the collection of nanometer thin films without spectral contamination from sub-layers and demonstrated improved collection parameters. Chapter 3 evaluated a constructed dispersive Raman spectrometer operating with near–infrared (NIR) wavelengths to determine polyethylene terephthalate film thickness for process monitoring purposes. Chapter 4 demonstrated the potential capabilities of NIR-diffuse reflectance spectroscopy for the detection of high energy materials to provide alternative methods of detection and increase safety in the battlefield. Chapter 5 was an investigation of a planar array spectrograph employed as a real-time detector for liquid chromatography separations.

Committee: André Sommer Dr. (Advisor); Neil Danielson Dr. (Committee Chair); Shouzhong Zou Dr. (Committee Member); David Oertel Dr. (Committee Member); Paul James Dr. (Committee Member) Subjects: Chemistry