Master of Science, The Ohio State University, 1953, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Arts, The Ohio State University, 1915, Graduate School

Committee: Not Provided (Other) Subjects:

Doctor of Philosophy, Miami University, 2024, Biology

CHAPTER 1: Nutrient excretion by fish supports a variable but significant proportion of lake primary productivity over 15 years. This chapter analyzes the long-term importance of excretion from gizzard shad for primary production in a midwestern reservoir using a supply:demand (S:D) approach and considers environmental and population variables that best predict the S:D ratio. Gizzard shad excretion supported a variable proportion of phytoplankton phosphorus demand, and it supported more demand during the summer than spring. Stream discharge, temperature, and gizzard shad population biomass best predicted S:D during the spring, while the biomass of the young-of-year best predicted S:D in the summer. CHAPTER 2: Combined influence of parasites and temperature on nutrient excretion rates and body stoichiometry of a freshwater fish. The rates of excretion from fish and the ratios of the nutrients excreted are expected to change as aquatic ecosystems warm. An experiment examined the excretion rates from bluegill under three climate scenarios and a range of natural parasite intensity. Carbon and phosphorus excretion increased with temperature but declined with parasite load, and the C and N concentrations in fish bodies declined with parasite load. CHAPTER 3: Ontogenetic changes in the gut microbiomes of Gizzard Shad and Bluegill and their relationship to nutrient excretion. The microbial communities within the guts of animals contribute to their health, but little is known about how these communities change with development and contribute to ecosystem processes. We conducted an exploratory study to learn about the gut microbiome of larval, young-of-year, and adult gizzard shad and bluegill as well as the relationship between microbiomes and excretion. We found that the two fish species had similar microbial communities as larvae, but the communities were different in the adults. The guts of adult gizzard shad contained taxa that are believed to fix nitrogen as well as s (open full item for complete abstract)

Committee: Michael Vanni (Advisor); Melany Fisk (Committee Member); Matthew Saxton (Committee Member); Roxane Maranger (Committee Member); Christopher Myers (Committee Member); María González (Committee Member) Subjects: Biogeochemistry; Biology; Environmental Science; Limnology; Science Education

MS, University of Cincinnati, 2023, Medicine: Industrial Hygiene (Environmental Health)

Humans can be exposed to hazardous chemicals through the three main routes of exposure which are inhalation, ingestion, and dermal. The hand – to – mouth behavior in infants and toddlers is a common route of exposure due to infants' and toddlers' exploratory behavior. Exposures to hazardous chemicals can be measured by biomonitoring. Biomonitoring measure the total exposure at an individual level from all exposure routes and sources. With the infant's exploratory behavior, primarily from the infants crawling, we asked whether infant internal doses of polyhalogenated organophosphate (PHOP) flame retardants are higher than the doses found in adults. The project identified human biomonitoring data for PHOPS from published articles. The three main polyhalogenated organophosphate flame retardants were: tris (1-chloro – 2 – propyl) phosphate, tris (2 – chloroethyl) phosphate, and tris (1, 3 – dichloroisopropyl) phosphate). A total of four hundred and seven published data articles were initially reviewed by the team for screening. For the light extraction, two hundred and ninety-nine published data articles were screened. Out of the two hundred and ninety-nine articles a total of one hundred and thirty were screened for this master's thesis, and reverse dosimetry was conducted on five articles with data on children or other potential highly exposed groups. The internal dose of PHOPS were calculated by applying reverse dosimetry to the concentrations in the human urine. We currently, do not have enough evidence to determine whether infants have a higher internal dose than adults. The results indicate that further investigation on infant and adult internal doses of PHOPS is needed.

Committee: Kermit Davis Ph.D. (Committee Chair); John Reichard PharmD Ph.D. (Committee Member); Lynne Haber Ph.D. (Committee Member); Mary Beth Genter Ph.D. (Committee Member) Subjects: Environmental Science

Doctor of Philosophy, The Ohio State University, 2021, Environment and Natural Resources

Headwater streams are common features of forested landscape and provide critical resources to near-stream riparian forests and downstream aquatic habitat. In many small streams in the southern Appalachians, often narrow and heavily shaded, these systems are almost entirely dependent on external input of nutrients. The volume and quality of nutrients available to headwater ecosystems varies through space and time, depending on the species of trees present in riparian forests, the time of year, and the rate of litter-processing by invertebrates. Additionally, nutrients are not distributed uniformly through aquatic ecosystems, and may be moved or aggregated by both physical and biological processes. Despite the perceived greater reliance on allochthonous input, there has been little work to identify how wildlife inhabiting smaller streams are facilitating stream nutrient dynamics both within streams and riparian systems. To increase our understanding of the role of animals in headwater streams, my research investigates the patterns of density, biomass, foraging, and excretion in the Black-bellied salamander (Desmognathus quadramaculatus), the largest, most-aquatic species of salamander occurring in fishless headwaters of the southern Appalachians. Desmognathus quadramaculatus forage both within and directly around streams, spending significant amounts of non-foraging time in stream banks or under partially submerged cover objects. Additionally, D. quadramaculatus have a 3-year larval period in this region and require permanent aquatic habitat for larval development. These traits suggest D. quadramaculatus may play a substantial role in the transfer of nutrients between riparian and aquatic ecosystems. The primary objective of my research was to (1) identify spatial patterns in stream-associated salamander density and (2) evaluate the extent to which D. quadramaculatus move nutrients between aquatic and terrestrial habitat through patterns in foraging and excretion. (open full item for complete abstract)

Committee: William Peterman (Advisor); Christopher Tonra (Committee Member); Mazeika Sullivan (Committee Member) Subjects: Aquatic Sciences; Biology; Conservation; Ecology; Environmental Science

Doctor of Philosophy, The Ohio State University, 2020, Animal Sciences

A study was designed to evaluate the effects of energy source and feeding level on total tract nutrient digestibility and nitrogen excretion in Miniature Horse geldings. Further investigation into nutrients and their concentrations were done to determine if more accurate estimates of digestible energy (DE) could be attained by applying a summative model that accounts for actual digestibility of nutrients, including residual organic matter (ROM). For chapter 3, six mature Miniature Horse geldings (8.3 ± 3.5 yr) were used in a 6  6 Latin square design and randomly assigned to one of six diet sequences for six 14-d periods. Diets consisted of mixed grass hay plus one of three energy supplements: oats, beet pulp, or rice bran at high (75% DE by supplement and 25% DE by hay) or low (40% of DE by supplement and 60% DE by hay) levels of inclusion based on predicted DE values Pagan (1998). Higher inclusion level of energy supplement increased apparent total tract digestibility of DM (P ≤ 0.06), OM (P ≤ 0.01), and LCFA (P ≤ 0.01). Supplement type × level interactions were found (P < 0.10) for variables relating to intake, digestibility, and nitrogen output. An energy source × level interaction was detected (P ≤ 0.03) when total tract apparent N digestibility was corrected for bacterial N loss; however, there were no differences across treatments except for BPH being lower than all others. Urinary N output was increased (P ≤ 0.02) in horses fed BPL had compared to BPH but was not different (P ≥ 0.10) between horses fed OH or OL. Urinary N excretion as a percent of N intake was higher (P ≤ 0.04) for horses fed rice bran than beet pulp, but both were not different (P ≥ 0.10) from horses fed oats. Both energy source (P ≤ 0.03) and inclusion level (P ≤ 0.01) affected fecal N output (g/d), which increased for treatments with greater N intake (low inclusion), and the main effect of oats decreased (P ≤ 0.03) fecal N over beet pulp or rice bran. Beet pulp supplementation increas (open full item for complete abstract)

Committee: Jeffery Firkins (Advisor); Laurie Lawrence (Committee Member); William Weiss (Committee Member); Anthony Parker (Committee Member) Subjects: Animal Sciences

Master of Science, The Ohio State University, 2017, Animal Sciences

This research was designed to study the long-term effects of feeding a high corn reduced-fat distillers grains (RFDG) on long-term performance, and nutrient excretion and utilization of dairy cattle and if the addition of monensin to a high-RFDG diet affected performance and nutrient excretion. To assess these objectives, 36 mid-lactation Holstein cows were fed either a control (CON), a 28.8% RFDG diet (DM basis) replacing SBM, soyhulls, and supplemental fat and calcium phosphate (DG), or the DG diet with monensin at 20 mg/kg of DM (DGMon). The experiment was conducted for 11 weeks during which dry matter intake (DMI); milk yield, composition, and fatty acid profile; fecal, and urinary excretion and milk secretion of nitrogen (N), phosphorus (P) and sulfur (S) were measured. For the production portion of the experiment, RFDG diets (i.e., DG + DGMon) vs. CON did not affect milk yield (40.3 vs. 40.8 kg/d), but decreased DMI (24.9 vs. 26.4 kg/d), milk fat yield (1.12 vs.1.55 kg/d), milk protein yield (1.24 vs. 1.32 kg/d), and energy-corrected milk yield (37.7 vs. 43.5 kg/d). Adding monensin to the DG diet (i.e., DGMon vs. DG) did not affect DMI (24.4 vs. 25.4 kg/d) and milk yield (39.2 vs. 41.3 kg/d), but decreased milk fat yield (1.08 vs. 1.23 kg/d), milk protein yield (1.20 vs. 1.28 kg/d), and energy-corrected milk yield (36.0 vs. 39.4 kg/d). Additionally, difference in DMI between treatments increased as the experiment progressed and tended to be different by the conclusion of the trial (27.8, 25.4, and 23.4 kg/d for CON, DG and DGMon, respectively). Furthermore, milk fat yield and energy-corrected milk yield decreased for DG diets vs. CON as the experiment progressed. For milk fatty acid profile, feeding DG and DGMon compared to CON resulted in an increased concentration of trans-10, cis-12 18:2, trans-10 18:2, long-chain (> 16C), and polyunsaturated fatty acids, and a decrease in short-chain (<16C) and most odd- and branched-chain fatty acids compared with CON (open full item for complete abstract)

Committee: Chanhee Lee (Advisor); William Weiss (Committee Member); Thaddeus Ezeji (Committee Member) Subjects: Animal Sciences

Master of Science, The Ohio State University, 2015, Entomology

Mosquitoes are one of the major threats to human health worldwide. They are vectors of protozoans, arboviruses, and filarial nematodes that cause diseases in humans and animals. The Asian tiger mosquito Aedes albopictus is a vector of medically important arboviruses such as dengue fever, chikungunya fever, yellow fever, among others. Control of these diseases often involves control of the mosquito vectors with chemical insecticides. However, the use of a limited number of chemicals with similar modes of actions has led to resistance in several mosquito species. The development of new insecticides with novel modes of action is considered a promising strategy to overcome resistance. The Piermarini lab has recently shown that the renal (Malpighian) tubules of mosquitoes are promising physiological targets to disrupt for killing mosquitoes via a novel mode of action. The Malpighian tubules play a critical role by mediating the rapid excretion of water and ions derived from the ingested blood. However, the physiological roles of Malpighian tubules during the chronic processing of blood meals after the initial diuresis is complete (~1-2 h after feeding) are not known. Therefore, the goal of this thesis was to characterize the transcriptomic dynamics of Malpighian tubules at 3 h, 12 h, and 24 h after blood feeding using next generation sequencing (RNA-Seq). In Chapter 2, we generated single-end sequences of cDNA libraries derived from Malpighian tubules of non-blood fed and blood fed A. albopictus (adult females) and mapped them to the existing genome of Aedes aegypti. In brief, our results suggest that the Malpighian tubules switch from a tissue dedicated to salt and water excretion to one more focused on the detoxification and excretion of metabolic wastes associated with blood meal processing (e.g., heme, ammonia). In Chapter 3, we generated paired-end sequences of cDNA libraries derived from Malpighian tubules of non-blood fed and blood fed A. albopictus and assembled (open full item for complete abstract)

Committee: Peter Piermarini PhD (Advisor); Andrew Michel PhD (Committee Member); David Denlinger PhD (Committee Member) Subjects: Entomology

Doctor of Philosophy, The Ohio State University, 2006, Evolution, Ecology, and Organismal Biology

Lake Erie is facing many perturbations. This study focuses on two issues, the external phosphorus loading and dreissenids' invasion, and investigates the interactions of the responses of the lower trophic levels to these two stressors. I construct an ecological model, EcoLE, based on a USEPA two-dimensional hydrodynamic and water quality model, CE-QUAL-W2. Data from the field year 1997 are used to calibrate the model, while data from 1998 and 1999 are used for verification. There is a good agreement between the modeled and field-measured state variables, and EcoLE catches the major characteristics of the physical, chemical and biological processes found in Lake Erie. We are confident in using this model for qualitative analysis, but one should be cautious in using it for quantitative predictions of Lake Erie processes. When I turn off the turbulent mixing processes, total dissolved phosphorus (TP-F) becomes concentrated in the lower water strata and diatom biomass decreases dramatically. When I turn on the mixing processes again, there is more TP-F in the upper water strata but less TP-F accumulated in the whole water column, because non-diatom edible algae (NDEA) and diatoms become more abundant in the water column. Blue-green algae are less affected by hydrodynamics but depend on the amount of available phosphorus in the whole water column. When I turn off the chemical and biological processes, external TP loads are distributed throughout the western basin and the west central basin as a result of physical mixing. External TP loads have minor direct effects on the east central and the eastern basins, where up to 60% of the daily algal P-demands come from SRP released by organic matter decomposition and by algal and crustacean P excretion. Dreissenid mussel daily grazing impact is less than 10% of the NDEA and diatom biomass in the western basin, and only 1-2% in the central and eastern basins. Impacts of dreissenid nutrient excretion become more important than the (open full item for complete abstract)

Committee: David Culver (Advisor) Subjects: Biology, Limnology

Doctor of Philosophy, The Ohio State University, 2003, Animal Science

The mechanism of action of 2-hydroxy-4-(methylthio) butanoic acid and its effects on N efficiency, ruminal variables, and milk production and composition were examined. In Trial 1, metabolizable protein (MP) supply and AA balance was manipulated through selection of highly digestible RUP sources and Met supplementation. Treatments were: 1) 18.3 % crude protein with low estimated intestinal digestibility of RUP; 2) 18.3 % CP with high digestibility RUP; 3) 16.9 % CP with high digestibility RUP; and 4) 17.0 % CP with high digestibility RUP and supplemental Met. Supplementing the highly digestible RUP source with rumen available and rumen escape sources of Met resulted in maximal milk and protein production and maximum N efficiency by cows during the production trial. In Trial 2, continuous culture fermenters were used to determine the optimal concentration of HMB for digestibility of carbohydrates and synthesis of microbial N. Treatments were three concentrations of HMB (0, 0.055, and 0.110 %) and one concentration of dl-Met (0.097 %). Digestibility of carbohydrate, other than ADF, was largely insensitive to treatment. Differences in concentration and production of individual VFA were seen and the proportion of bacterial N produced from NH3-N decreased linearly with increasing HMB. This suggests that supplementation of HMB may have a sparing effect on branched chain volatile fatty acids. In trial 3, eight cows were used to examine the passage of HMB from the rumen, ruminal effects of HMB, and effects on production, N utilization, VFA, and protozoa. Samples of omasal fluid were used to determine the amount of Met supplements passing out of the rumen. Treatments were: (1) no methionine (2) 2-hydroxy-4-methylthiobutanoic acid at 0.10% of DM; (3) isopropyl HMB at 0.13 % of DM; and (4) dl-methionine at 0.088% of DM. Digestibility in the rumen was not different. Protozoa were increased numerically in the omasum by HMB and HMBi treatments. The percentage of HMB that passed i (open full item for complete abstract)

Committee: Normand St-Pierre (Advisor) Subjects:

Master of Science, Miami University, 2003, Zoology

Fish are important in coupling benthic and pelagic habitats by consuming benthic prey and providing essential nutrients (nitrogen N and phosphorus P) to algae. However, because a complete understanding of fish effects on nutrient dynamics is still lacking, I measured how fish excretion rates (N and P) are affected by variable consumption rates under laboratory and field conditions. Then measured the effects changes in excretion rates had on community and nutrient dynamics. Results showed that variable consumption rates can alter fish excretion rates of nutrients and that algal biomass and sedimentation increased when fish fed on benthic prey, compared to fish not fed benthic prey. Thus, providing experimental evidence that benthic-pelagic coupling, via fish induced translocation and sedimentation shapes pelagic food-webs and cycling of nutrients between pelagic and benthic habitats. Lastly, fish body and excreted N:P both increased with consumption rate, suggesting that stoichiometry models need to better incorporate consumption rate.

Committee: Mike Vanni (Advisor) Subjects: Biology, Zoology

Doctor of Philosophy, Case Western Reserve University, 2008, Pathology

Human immunodeficiency virus (HIV-1) is estimated to have newly infected 2.5 million people worldwide in 2007 (UNAIDS 2007) and current treatments only delay the course of this disease. HIV is primarily transmitted through mucosal surfaces and initially propagates in the lamina propria below the polarized epithelial mucosa. IgA, produced in the lamina propria and transcytosed across the mucosal epithelium, is the first line of defense against HIV. This study was initiated to determine if IgA against the more invariant internal HIV proteins are capable of mediating intraepithelial viral neutralization. Polarized primate epithelial cells expressing the polymeric immunoglobulin receptor (pIgR) were transfected with proviral DNA, and IgA was added to the basolateral side. Transcytosing IgA against the HIV proteins Gag and RT significantly inhibited HIV replication in a concentration dependent manner. Consistent with intracellular neutralization, colocalization of the internal proteins and IgA was visualized with confocal microscopy. Thus, at least in the context of infections of polarized epithelia, antibody-mediated neutralization is not necessarily restricted to viral surface antigens. Another potential IgA defense mechanism against HIV is immune excretion, where IgA can bind and form immune complexes in the basolateral compartment (lamina propria) that can be transported and released apically (luminal). IgA against HIV envelope proteins was used to study the ability of polarized epithelial cells to excrete virus from the basolateral to apical surface via pIgR-mediated binding and transport of HIV-IgA immune complexes. Excretion was dependent on IgA concentration and exposure time. Combination of IgA against gp120 and gp41 showed a synergistic increase of excretion. Each IgA antibody demonstrated different levels of excretion ability, which correlated with the ability of the different IgAs to bind HIV and of the immune complexes to bind pIgR. Confocal microscopy showe (open full item for complete abstract)

Committee: Yung Huang (Advisor) Subjects: Health Sciences, Immunology