Master of Science (MS), Wright State University, 2024, Biological Sciences

Emerald ash borer (EAB), Agrilus planipennis, is an invasive pest that significantly impacts olive trees (Olea europaea). This study aimed to assess the role of abiotic stress factors such as drought and salinity in influencing plant defenses and resistance to EAB, while also examining cultivar variation in resistance. The study specifically aimed to address: (1) What effects do varying degrees of abiotic stress (drought, salinity) have on olive trees' antioxidant and peroxidase activity in olive tree? (2) Do distinct olive cultivars exhibit varying levels of resistance to EAB under various stressors? We used a controlled experimental design with two stress treatments (drought and salinity) and 20 olive cultivars to conduct the bioassay. Growth metrics (height and stem diameter), peroxidase activity, and antioxidant activity were measured, while EAB survival and performance were assessed by monitoring larval feeding and growth. Results indicated no significant differences in antioxidant activity between treatments, although low salinity slightly enhanced antioxidant responses. Peroxidase activity was highest under high salinity, and growth responses varied by treatment and cultivar, with Leccino showing the highest antioxidant activity. EAB larvae performed best under drought conditions but exhibited poor survival on certain cultivars. These findings suggest that abiotic stress influences both plant defense mechanisms and pest resistance, with cultivar-specific responses to stress and pest pressure.

Committee: Don Cipollini Ph.D. (Advisor); John Stireman III Ph.D. (Committee Member); Volker Bahn Ph.D. (Committee Member) Subjects: Agriculture; Agronomy; Biology; Botany; Chemistry; Ecology; Entomology; Environmental Science; Environmental Studies; Nutrition; Plant Biology; Plant Pathology; Plant Sciences; Public Health; Soil Sciences

Master of Science, The Ohio State University, 2007, Graduate School

Committee: Not Provided (Other) Subjects:

Doctor of Philosophy, The Ohio State University, 2024, Materials Science and Engineering

This dissertation presents biochemical sensing systems for wearable, implantable, and high-resolution chemical sensing applications. By integrating biorecognition elements, sensing interfaces, and wireless communication strategies, we aim to provide a low-cost, reliable, and highly accurate platform for real-time biochemical monitoring in clinical and experimental settings. We first demonstrate a wireless sensing system that is miniaturized, lightweight, and compatible with common biochemical sensing interfaces. Inspired by RF tuning circuits, our simple circuit design allows battery-free operation and accurate monitoring of multiple biomarkers. The modular design separates the inductive coupling unit and the electrochemical sensing interface, minimizing strain-induced changes and ensuring accurate recording. This system is compatible with common electrochemical sensing methods, including ion-sensitive membranes (ISM), aptamer-based sensors, and enzymatic interfaces. And allow for the detection of ions, neurotransmitters, and metabolites across different application scenarios. For instance, a "smart necklace" consists of glucose sensors, that are capable of wirelessly detecting sweat glucose during exercise. A wearable skin patch monitored cortisol levels in sweat showcases the functional adaptability for stress-related biomarker detection. Additionally, a miniaturized implant prototype illustrated the potential for continuous in vivo monitoring. Our work also introduces a portable vector network analyzer (pVNA) designed to overcome the size limitations of traditional VNAs. This research provides the design and working principle for a wearable reader, which allows for real-time monitoring of resonance frequency and Q factor of the inductive coupling wireless sensor. Furthermore, we introduce “NeuroThread”, a neurotransmitter-sensing platform that utilizes the cross-section of commercially available ultrathin microwires to serve as microelectrode. This cost (open full item for complete abstract)

Committee: Jinghua Li (Advisor); Heather Powell (Committee Member); Pelagia-Irene Gouma (Committee Member) Subjects: Engineering; Materials Science; Nanoscience; Neurosciences

Doctor of Philosophy, The Ohio State University, 2023, Mechanical Engineering

The extracellular matrix (ECM) is a 3D non-cellular polymer network that is present within all tissues and organs. The ECM is complex, dynamically remodeling, and crucial for maintaining homeostasis of the cellular microenvironment. The ECM provides not only a physical scaffold for cells, but also regulates various processes such as proliferation, migration, and differentiation of cells. Crosstalk between ECM constituents can occur either physically where cell-ECM interactions are regulated by the biophysical properties of the host tissue, or biochemically, through signaling molecules. On a biochemical level, interactions can happen through direct cell signaling, or through the ECM-mediated capture and release of potent signaling molecules. Studies have reported the effect of certain circulating molecules, like extracellular nucleic acids, and platelet derived growth factor (PDGF) in disease progression, such as in the case of cancer, cardiovascular, fibrotic, Parkinson, Alzheimer, and kidney diseases. On a biophysical level, modulation of the mechanical properties of the ECM by cells is believed to significantly influence the progression of certain diseased tissue such as in fibrosis, healing wounds, or the stroma of tumors, all of which are known to exhibit ECM remodeling through the cross-linking of fibrillar collagen and/or deposition of non-collagenous ECM. In addition, slowly moving interstitial flow through the ECM plays a major role in modulating cancer cell migration that may promote metastasis by redistributing morphogens, leading to chemotaxis, or through the activation of cell-surface mechanosensors, such as focal adhesion proteins, that promote cell motility. Here, I present hybrid in vitro systems that utilize microfluidic devices and DNA-based nanoscale sensors that enable measuring biochemical cues and biophysical forces in the ECM at a sub-cellular level. This thesis is organized into three parts. Part 1 covers engineering the ECM with DNA-b (open full item for complete abstract)

Committee: Carlos Castro (Advisor); Benjamin Walter (Committee Member); Jonathan Song (Advisor); Gunjan Agarwal (Committee Member) Subjects: Biomedical Engineering; Mechanical Engineering; Nanotechnology

Master of Science in Chemistry, Youngstown State University, 2023, Department of Biological Sciences and Chemistry

The enzyme β-galactosidase plays a role in the hydrolysis of lactose to galactose and glucose. Depending on the source, β-galactosidases can also carry out transglycosylation. This research was aimed at the biochemical characterization of β-galactosidase from Enterobacter sp. YSU. The enzyme is within the family of glycoside hydrolases. The Enterobacter sp. YSU β-galactosidase was overexpressed in E. coli. Subsequently, it was isolated using ammonium sulfate precipitation and a Q-Sepharose ion-exchange column. The single polypeptide chain protein contains 1056 amino acids with a molecular weight of 120 kDa. An in-gel activity test using 4-methylumbelliferyl-β-D-galactopyranoside established that the protein is active in its dimeric form. Dissociation of β-galactosidase into monomers in the presence of detergents like SDS results in the loss of enzymatic activity. The enzyme shows its optimal activity at pH 7.4 and a temperature of 40 °C. It has a limited substrate specificity of o-nitrophenyl-β-D-galactopyranoside (o-NPGal) and lactose. The catalytic parameters of the enzyme for o-NPGal were determined: KM is 0.3 mM, and kcat is 146 s-1. With respect to lactose, KM is 22 mM, and kcat is 3.86×103 min-1. Galactose competitively suppresses β-galactosidase activity, whereas glucose uncompetitively inhibits the enzyme. The enzymatic activity of β-galactosidase was affected by the presence of Mg2+ but not other divalent ions like calcium, zinc, or copper. Dimethyl sulfoxide caused a notable decrease in the activity of β-galactosidase while 2-mercaptoethanol had no effect on the activity of the enzyme. The β-galactosidase from Enterobacter sp. YSU showed a similar KM for lactose with most β-galactosidases isolated from other organisms but a higher kcat, and, therefore, there is a need to explore its applications in the hydrolysis of lactose.

Committee: Nina Stourman PhD (Advisor); Michael Serra PhD (Committee Member); Jonathan Caguiat PhD (Committee Member) Subjects: Biochemistry; Biology; Biomedical Research; Chemistry; Food Science; Health Sciences; Molecules

Doctor of Philosophy, The Ohio State University, 2021, Horticulture and Crop Science

Water deficit stress (WDS) is the most destructive abiotic stress limiting global crop productivity with precarious economic and sociological impacts. Plant growth-promoting fungi Trichoderma are studied as accessible and sustainable tools for enhancing plant growth and mitigating biotic and abiotic stressors in both research and commercial production settings. However, whether different species or isolates of Trichoderma have adapted as symbionts in stress environments remains unclear. In addition, plant genotype also influences the degree of fungal colonization and crop stress-mitigating potential of Trichoderma even for the established commercial isolates. This work evaluates the ability of novel isolates from several species of Trichoderma, primarily native to different agroecological regions in Nepal, to improve growth in different tomato genotypes exposed to WDS conditions. The results demonstrate differences in the ability of Trichoderma isolates to thrive in a low moisture environment and to confer tolerance to water deficit in the tomato plant. Trichoderma asperelloides NT33, isolated from a dry region, delivered consistent performance advantages to its tomato partners. NT33 inoculation improves the morphological, physiological, and biochemical parameters in drought susceptible tomato genotype and can ameliorate the negative impact of WDS in plants by modulating the plants' natural defense systems. Further, transcriptomic analysis was conducted to elucidate the key molecular mechanisms and candidate genes involved in water deficit response. The study showed that the metabolic pathways involved in secondary metabolite production and antioxidative defense are the main mechanisms adopted by NT33 inoculated plants for maintenance of homeostasis balance in the plant under WDS conditions compared to non-inoculated control plants. This research delivers insights into mechanisms adopted by novel Trichoderma isolates to increase plant growth and induce defense respo (open full item for complete abstract)

Committee: Joseph Scheerens (Advisor); Maria Soledad Benitez Ponce (Advisor); Sally Miller (Committee Member); Michelle Jones (Committee Member); Joshua Blakeslee (Committee Member) Subjects: Agriculture; Horticulture; Physiology; Plant Biology

Doctor of Philosophy, The Ohio State University, 2019, Food, Agricultural and Biological Engineering

Lactic acid is a platform chemical that can be utilized for a variety of applications in food, medical, packaging, and cosmetics industries. The global market for lactic acid is expected to grow substantially from $2.1 billion in 2016 to $9.8 billion in 2025. Lactic acid can be produced from both petroleum and biobased sources; however, the demand for lactic acid produced from biobased feedstock sources is expected to increase due to growing consumer awareness of the need for sustainability, biodegradability, recyclability and green packaging in different industries. Biobased lactic acid can be produced from starch-rich feedstocks, such as corn grain, and lignocellulosic feedstocks, such as corn stover and miscanthus. Lactic acid produced from biobased feedstocks can yield lactic acid isomers suitable for applications in the food and medical industries. Despite huge growth potential, the techno-economics and environmental impacts of different pathways for biobased lactic acid production are not well studied. Thus, the objective of this dissertation was to analyze the techno-economics and life cycle environmental impacts of producing lactic acid from biobased feedstocks, including corn grain, corn stover and miscanthus. These feedstocks were selected based on their current availability and future potential for biorefinery use in the U.S. The study evaluated different logistics and conversion pathways by developing comprehensive techno-economic and life cycle assessment models. The models incorporated data collected from the literature related to biomass production, harvest, post-harvest logistics and conversion to lactic acid. Three grain logistics scenarios were defined based on intermediate grain storage at 1) farm storage structure, 2) country elevator, and 3) both, before the grain delivery to the biorefinery. The 90% central range (CR) for the grain logistics cost, including costs for grain harvest, hauling, and storage, was $36-50 per metric ton (t). The grai (open full item for complete abstract)

Committee: Ajay Shah (Advisor); Erdal Ozkan (Committee Member); Harold M. Keener (Committee Member); Katrina Cornish (Committee Member) Subjects: Agricultural Engineering; Engineering

Doctor of Engineering, Cleveland State University, 2017, Washkewicz College of Engineering

The dairy industry generates abundant milk waste waters characterized by high biochemical oxygen demand (BOD) and chemical oxygen demand (COD) concentrations that can be very harmful to the environment, if left untreated. Electrocoagulation (EC) has been in use for waste water treatment. The treatment application uses aluminum electrodes and iron or the combined hybrid Al/Fe electrodes. Milk waste water contains high concentration organic pollutants and the main constituents of those organics are carbohydrates, proteins and fats, originating from the milk. The process of separating the flocculated sludge from waste water that has been treated using the electrocoagulation process can be accomplished by the flotation processes. The electroflotation technology is effective in removing colloidal particles, oil, grease, as well as organic pollutants from waste water. This study uses electrochemical and electroflotation treatment of milk waste water by means of an aluminum electrode with specific parameters including total organic carbon (TOC), pH, turbidity, transmittance, and temperature. Even though the electrochemical and electroflotation treatment processes have been around for some time, it has not been thoroughly studied. This study is going to highlight the importance of this technique as a pre-treatment method of milk waste water and its contribution to the reduction of pollutants in the milk processing industry. Furthermore, the process of electroflotation and electrochemical flotation continuously prove to be effective in remediation of varieties of pollutants of different chemical compositions and have the ability to achieve a very high treatment efficiency.

Committee: Yung-Tse Hung Ph.D. (Committee Chair); Walter Kocher Ph.D. (Committee Member); Lili Dong Ph.D. (Committee Member); Chung-Yi Suen Ph.D. (Committee Member); Saili Shao Ph.D. (Committee Member) Subjects: Civil Engineering; Engineering; Environmental Engineering

Master of Sciences (Engineering), Case Western Reserve University, 2017, Biomedical Engineering

Gleason score and nomograms are current methods used to evaluate prostate cancer (CaP) but are subject to inter-observer variability. The combination of computer extracted measurements from H&E and Feulgen stained CaP images could allow for improved characterization of disease appearance and enable accurate prediction of which patients are at risk for biochemical recurrence (BCR) and metastasis following radical prostatectomy. Nuclear morphology, architecture, and texture features were extracted from the tumor and tumor-adjacent benign regions of stained tissue microarray images of 260 CaP patients. A machine learning classifier was trained with the most predictive features identified on the training set to predict outcomes on the validation set. Clinical predictors of Gleason score and nomograms had a maximum prediction accuracy of 70.4% for BCR and 60% for metastasis on the validation set. The combination of H&E and Feulgen features yielded an accuracy of 95.63% for BCR and 70.8% for metastasis predictions.

Committee: Anant Madabhushi (Advisor); Satish Viswanath (Committee Member); David Wilson (Committee Member); Robin Elliott (Committee Member) Subjects: Biomedical Engineering

Doctor of Philosophy, The Ohio State University, 1986, Graduate School

Committee: Not Provided (Other) Subjects: Health Sciences

Doctor of Philosophy, The Ohio State University, 1986, Graduate School

Committee: Not Provided (Other) Subjects: Health Sciences

Doctor of Philosophy, University of Toledo, 2013, Chemistry

Protein ligand interactions play a key role in the majority of all biological processes. Proteins display unique binding sites that are recognized by specific ligand through distinct interactions. Characterization of these interactions provides insights that are exploitable for designing drugs. Here we study enzyme-substrate interactions in a protein encoded by Helicobacter pylori (H. pylori), which is associated with gastric and duodenal ulcers. H. pylori MTAN (HpMTAN) catalyzes the hydrolysis of N-ribosidic bonds of at least four different adenosine based substrates; S-adenosylhomocysteine (SAH), 5'-methylthioadenosine (MTA), 5'-deoxyadeosine (5'-DOA) and 6-amino-6-deoxyfutalosine. This hydrolytic activity places MTAN at the hub of at least seven fundamental metabolic pathways: the purine salvage pathway, the methionine salvage pathway, S-adenosylmethionine (SAM)-dependent methylation pathways, polyamine biosynthesis, the production of quorum sensing molecules and menaquinone biosynthesis. Campylobacter and Helicobacter are dependent on MTAN for menaquinone synthesis, an essential metabolite for bacterial viability, making MTAN an excellent target for the development of new treatments for Helicobacter infections. To structurally characterize the interactions between MTAN and its various substrates, complexes of an inactive mutant of the HpMTAN with two known substrates, 5'-methylthioadenosine (MTA) and S-adenosylhomocysteine (SAH) were formed and crystallized. The crystal structures of mutant HpMTAN complexed with SAH and MTA were solved to 1.2 and 1.6 A respectively. The HpMTAN-SAH co-crystal structure represents the first visualization of interactions between the homocysteine moiety of SAH and the 5'-alkylthiol-binding subsite of the MTAN active site. The co-crystal structure of wild-type MTAN with products, adenine and S-ribosylhomocysteine, was determined to 1.54 A resolution. The similarities and differences in these three structures highlight features tha (open full item for complete abstract)

Committee: Donald Ronning PhD (Committee Chair); John Bellizzi PhD (Committee Member); Steve Sucheck PhD (Committee Member); Constance Schall PhD (Committee Member) Subjects: Chemistry

PhD, University of Cincinnati, 2008, Engineering : Electrical Engineering

The objective of this research is to develop new functional nano/micro bead-packed columns on polymer lab-on-a-chips (PLOC) using self-assembly microfabrication technologies for practical on-site biochemical analyses or point-of-care clinical diagnostics. In order to achieve the goal of this research, new polymer microfabrication methods such as (a) a multi-chip assembly method for polymer chips using pin-hole pair structure and (b) a self-assembly and packing method for nano/micro beads on polymer chips have been newly developed and characterized. The novel microfabrication methods have been applied for the realization of practical polymer lab chips such as (a) sample preparation for matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and (b) on-chip capillary electrochromatography with electrochemical detection for on-site clinical analysis. The state-of-art microfabrication techniques have been demonstrated by development and characterization of high quality disposable polymer capillary electrophoresis (CE) microchips. To realize polymer lab-on-a-chips in a multilayer format, a new assembly technique using pin-hole pair structure has been developed for the fabrication of multilayered polymer chips. This newly developed technique directly addresses the alignment problem that has been considered as one of the most difficult tasks in the bonding assembly of multiple polymer layers for the multi-layered polymer lab chips. Functional on-chip bead-packed columns using a slurry packing method and a self-assembly method have been developed and characterized in this work. An on-chip reversed phase chromatography (RPC) column packed with RPC media (SOURCE 15RPC) has been realized using the slurry packing method, where the geometrical restrictions with precise alignments, which are essential for the packing process, were achieved using the pin-hole pair structure assisted assembly technique. The RPC column integrated with the sample preparation chip (open full item for complete abstract)

Committee: Chong Ahn (Committee Chair); Joseph Nevin (Committee Member); Ian Papautsky (Committee Member); William Heineman (Committee Member); Patrick Limbach (Committee Member); Paul Bishop (Committee Member) Subjects: Electrical Engineering

Doctor of Philosophy, The Ohio State University, 2008, Environmental Science

Sanitary sewer overflow (SSO) has characteristics of high flow rate, low and varying pollutant concentrations, and low frequency of events. Fixed media bioreactor (biofilter) is a proven technology used for wastewater treatment in unsewered rural areas. No previous research has been published on SSO treatment with fixed media bioreactors. This study expands the application of fixed media bioreactor technology by testing its feasibility in the treatment of SSO wastewater at high hydraulic loading rates. Five types of fixed media bioreactors – sand, textile peat, textile/sand, and peat/sand – were set up in the laboratory and used to treat SSO once a month. Wastewater from a simulated 25-year peak flow was loaded to the surface of bioreactors at 0.2 m/hr for 6 hr. Biochemical oxygen demand (BOD5), total suspended solids (TSS), ammonia nitrogen (NH4-N) and total phosphorus (TP) were measured as waster quality characteristics. Sand bioreactors showed the best system performance for treating SSO with effluent concentration of 14 mg BOD5/L, which met 7-day effluent limit for stream discharge from conventional treatment technologies in Ohio's antidegradation rule (3745-1-05). Linear regression and Bayesian models were applied for the factor analysis of organic matter removal. The results showed that the type of bioreactor media was the most significant factor. All bioreactors had the effluent concentrations of TSS < 18 mg/L, the discharge standard of the Ohio antidegradation rule. The bioreactors had the highest efficiency in the NH4-N and TP removal for a relatively short SSO event of 2 hr. The treatment capacity decreased with higher influent concentration during 4 hr and 6 hr loadings. The treatment efficiency was also evaluated in sand bioreactors with different resting period between two SSO events and different dosing strategies. The low frequency of SSO (1, 2, 3 and 6 months resting between events) did not show significant impact on the treatment performance. The pe (open full item for complete abstract)

Committee: Karen Mancl PhD (Advisor); Olli Tuovinen PhD (Committee Member); Anne Carey PhD (Committee Member); Robert Sykes PhD (Committee Member) Subjects: Environmental Engineering; Environmental Science; Technology

Doctor of Philosophy, The Ohio State University, 2002, Biochemistry

Human T-cell leukemia virus (HTLV) is an oncogenic retrovirus that is associated with leukemia and neurological disorders in humans. One of the viral regulatory proteins, Rex, is critical for viral replication and is involved in preferential binding, stabilization and export of unspliced and incompletely-spliced viral RNA transcripts from the nucleus to cytoplasm. The function of Rex is mediated through a cis-acting Rex-responsive element (RxRE) present in the viral RNA transcripts. We have reported previously that the phosphorylation (on serines) of HTLV-type 2 Rex (Rex-2) is required for efficient binding of Rex to HTLV target RNAs in vitro. To identify critical phosphorylation sites within Rex-2, we generated a panel of Rex-2 mutant derivatives in which serine and threonine residues throughout the protein were altered. Using a Rex-2 functional assay, we identified mutants that disrupt previously defined RNA binding/nuclear localization domain, the activation/nuclear export (NE) domain, and the putative multimerization domain. In addition, we identified a novel domain at the carboxy terminus that is important for Rex-2 function. One of the C-terminal mutants (S151A, S153A) displayed a reduction of the p26-phosphorylated conformation of Rex that also correlated with reduced Rex function. Replacement of both serine residues 151 and 153 with aspartic acid locked Rex-2 in a phosphorylated active state and restored Rex-2 function. Two-dimentional phosphoamino acid analysis of the Rex-2 mutant containing threonine residues at 151 and 153 revealed a decreased serine phosphorylation in conjunction with an increased threonine phosphorylation providing further evidence of in vivo phosphorylation of these residues. We next correlated a panel of functionally defective Rex-2 mutants with various biochemical properties to delineate any additional defects with these mutants. Our subcellular localization study indicates that the phosphorylation mutant, S151A,S153A showed diffuse (open full item for complete abstract)

Committee: Patrick Green (Advisor) Subjects: Biology, Molecular

Doctor of Philosophy, The Ohio State University, 2013, Food Science and Nutrition

Soy isoflavones have generated substantial interest in the last few decades. However, bioavailability, metabolism, bioactivity and structural fate of isoflavones have been the subject of much stimulating discussion. Of the many dietary variables of interest, diets rich in soy foods are hypothesized, to reduce the risk of prostate cancer or enhance the efficacy of prostate cancer therapy. Despite the significant effort invested in soy research and the many hypotheses that have emerged, evidence-based and scientifically established dietary interventions to prevent or enhance the therapy of prostate cancer, have yet to be defined. The evidence is derived from descriptive epidemiology, laboratory animal models, and in vitro studies, yet data from clinical intervention trials is limited. Integrating soy bioactive compounds in substantial amounts – levels common in Asian diets – and in their most bioavailable form into novel, food products appropriate for clinical trials may address this need. Two distinct soy breads were formulated to deliver 30 mg of isoflavones/80 g slice. In one bread type, the isoflavones occurred predominantly as glucosides while in the other soy bread the isoflavone existed predominantly as aglycones (potentially most active and more readily absorbed). We hypothesized the aglycone-rich soy-almond bread compared to the glycoside-rich soy bread would provide greater bioavailable soy isoflavones which will have a greater effect on health outcomes. Thus the aglycone rich bread will serve as an excellent source of bioavailable soy isoflavones for future large-scale randomized clinical trials designed to evaluate the health benefits of soy for the prevention of cancer, as complementary therapy for cancer, or to prevent and treat other age-related illnesses. A 20-week randomized phase II cross-over trial involving 40 men with known prostate cancer and escalating prostate specific antigen (PSA) was conducted and addressed the following objectives: a.) Op (open full item for complete abstract)

Committee: Yael Vodovotz PhD (Advisor); Steven Schwartz PhD (Advisor); Steven Clinton MD, PhD (Committee Member); Christopher Weghorst PhD (Committee Member) Subjects: Analytical Chemistry; Food Science; Nutrition; Oncology