Doctor of Philosophy, The Ohio State University, 2015, Chemical Engineering

Our three studies examine the factors of learning styles, student self-efficacy, collective (team) efficacy, attitudes, perceptions, and performance at individual and team levels. Each study addresses a different environment: (i) Individual Level—we are interested in how variability in learning styles engaged by specific exam problems may correlate with student learning styles, self-efficacy, and performance in our introductory chemical engineering course, Process Fundamentals (i.e., mass and energy or material balances); (ii) Team Level—we are interested in understanding how team composition with respect to learning styles (homogeneous vs. heterogeneous teams) may influence these factors in the upper level Unit Operations course; (iii) Combinatorial Level—we are interested in understanding how collective efficacy may influence individual self-efficacy and again if there are any correlations with learning styles and performance in the senior level Process Design and Development course. Some of the most interesting results of these studies have stemmed from the study on individual students, which has shown correlations between learning style preferences and performance in specific instances. Even more interesting, evaluating and characterizing the learning styles that exam problems engage has shown strong variations in problem types by instructor. This presents new questions regarding how these variations may affect student understanding and subsequent performance. Also included are details regarding a course developed in Technical and Professional Communication (for Chemical Engineers) that was offered Spring 2014 and Spring 2015.

Committee: David Wood (Advisor); James Rathman (Committee Member); David Tomasko (Committee Member) Subjects: Chemical Engineering; Education

Doctor of Philosophy, The Ohio State University, 2015, Evolution, Ecology and Organismal Biology

Communication between potential mates is of vital importance to the fitness of many taxa, allowing individuals to find one another, as well convey and receive information important in assessing a suitable mate. Signals involved in sexual communication can be transmitted through visual, vibrational and chemical modalities, with chemical communication being the oldest and most widespread. The ability to detect visual and vibrational cues often occurs across a range of inputs, while chemical communication has the potential for much higher specificity, as only those receivers possessing chemosensory cells attuned to the compounds used will be able to detect their presence. The detection and integration of multimodal signals into a behavioral response has been extensively studied in the Schizocosa ocreata (Hentz 1844) wolf spider (Lycosidae) model system. In this ground dwelling species, males respond to substrates containing female chemical signals with visual and vibratory courtship displays. While this response has been well characterized, the chemical identity of these signaling compounds is currently unknown, and pheromone identity has been understudied across spiders as a whole. The behavioral response of male S. ocreata to conspecific chemical signals has primarily been studied in the context of substrate bound female cues, though past studies have suggested that chemicals produced by conspecific male competitors may inhibit male courtship behavior, and have even suggested a role for olfaction.We further examined the role olfaction plays in male detection and location of females, and while we found no evidence that males are utilizing olfaction to find mates, we did observe behavioral changes to conspecifics of both sexes, and a reduction of activity in the presence of volatile cues from a predator. At levels of competitor cues that males are expected to encounter in nature, we found no evidence that male-male inhibition occurs in this species. In examining male r (open full item for complete abstract)

Committee: J. Andrew Roberts (Advisor); Susan Gershman (Committee Member); Roman Lanno (Committee Member) Subjects: Behavioral Sciences; Biology; Ecology

MS, University of Cincinnati, 2010, Arts and Sciences: Biological Sciences

In predatory animals such as spiders, females are often aggressive or potentially cannibalistic, and thus selection has favored males that recognize females and signal their identity and intent to mate at a distance. This often involves recognition of chemical cues or signals (pheromones) from females. Chemical communication is an important part of the mating process in the wolf spider Schizocosa ocreata, as cues associated with female silk are sufficient to elicit courtship from males. However, it is not known whether females also respond to chemical cues associated with male silk. Although responses of males to airborne chemical cues from females have been demonstrated in some spider species, this has not been well examined in S. ocreata. In this study, I examine how both male and female S. ocreata wolf spiders respond to silk-borne and airborne chemical cues from members of the same or opposite sex. I collected silk from mature males and females onto a piece of filter paper and recorded the amount of time that spiders spent in a stimulus chamber containing male silk, female silk, and no silk (control). Males spent more time on female silk, while females spent significantly less on female silk, but neither sex showed a significant difference between male silk and a control. In addition, I conducted studies in an olfactometer in which subjects were exposed to airborne chemical cues from a male spider, female spider, male silk, female silk, or a blank control. I scored the choice made as well as specific male courtship behaviors. Males and females showed no significant directional response to airborne cues from either sex, but males displayed courtship behaviors most often and at higher rates when exposed to airborne cues from females. Furthermore, I compared the rates of male courtship behaviors between airborne chemical cues and silk-borne cues from females and found that silk elicited higher rates of courtship than airborne chemical cues. I conclude that chemical (open full item for complete abstract)

Committee: George Uetz PhD (Committee Chair); Michal Polak PhD (Committee Member); Alan Cady PhD (Committee Member) Subjects: Biology

Doctor of Philosophy, The Ohio State University, 2007, Human Nutrition and Food Management

Cataract is the leading cause of vision loss worldwide and is treated only by surgical intervention. Oxidative stress-induced damage to the lens can accumulate with aging or exposure to environmental and/or chemical stressors. Lens epithelial cells (LEC) comprise the first cell layer exposed to stress, and LEC death is considered an initiating event in cataract development. Activation of stress-induced cell signaling pathways coordinates the LEC response to injury. The first objective of this research was to determine the mechanism(s) of cell death in human lens epithelial cells (HLE) exposed to environmental (ultraviolet B (UVB) radiation) and chemical stressors (hydrogen peroxide, (H 2O 2) and tertiary butyl hydroperoxide, (TBHP)). While all three stressors decreased HLE cell density, exposure to UVB resulted in changes in cell morphology, DNA fragmentation and annexin/propidium iodide staining consistent with apoptosis, whereas H 2O 2and TBHP treatment resulted in necrosis. Activation of signaling proteins such as JNK, c-Jun and DNA fragmentation factor 45 (DFF45) were observed only in UVB-treated cells. Gap junction intercellular communication (GJIC) facilitates nutrient transport in the lens, and is regulated by cell stress, cell signaling pathways and dietary compounds. The mechanism of this regulation is not clearly established, although changes in connexins, structural proteins of gap junction channels, is involved. Connexin 43 (Cx43) is the major connexin present in LEC. The second objective of this research was to examine the role of cell signaling pathways and the dietary compounds, retinoids and carotenoids, in modulating GJIC in canine LEC. Treatment with the protein kinase C (PKC) activator, TPA, significantly decreased GJIC in canine LEC and increased Cx43 phosphorylation. Inhibition of PKC partially restored TPA-inhibited GJIC and reduced Cx43 phosphorylation. Retinoic acid increased expression of Cx43 and enhanced GJIC in canine LEC. LEC utilize str (open full item for complete abstract)

Committee: Joshua Bomser (Advisor) Subjects: Health Sciences, Nutrition

Master of Science, Miami University, 2011, Zoology

The cellar spider, Pholcus manueli (Araneae, Pholcidae), has recently expanded its range and is now abundant throughout the Midwest. However, little is known about its biology and especially factors that might influence its dispersal. Studying P. manueli dispersal patterns should shed light on whether an individual can assess its environment and what factors might be important in the decision to disperse from an area. In a laboratory experiment, I observed both males and females dispersing from an environment perceived to be male dominant. In a field study, I observed that neither sex ratios nor density had a significant effect on the likelihood of dispersal. However, when comparing the amount of dispersal in the male and female biased populations, there again tended to be more dispersal in male dominated enclosures. Therefore, movement of these spiders between patches is caused, at least in part, by the demography of the population.

Committee: Ann Rypstra (Advisor); Alan Cady (Committee Member); Brian Keane (Committee Member) Subjects: Behavioral Sciences; Biology; Ecology; Zoology

Master of Science (MS), Bowling Green State University, 2006, Biological Sciences

Animals use sensory communication to locate conspecifics, food, shelter, and avoid predators. Using urine visualization techniques as well as Digital Particle Illumination Velocimetry, we examined the role of urinary signals and current generations during social interactions of male and female crayfish. Both reproductive and non-reproductive crayfish were paired to gain a better understanding of how reproductive state influences communication. Analyses of agonistic and mating events were paired in time with recorded urine release and current generation, illustrating a correlation of chemical communication with ritualistic social behavior. Four treatment groups were run with various pairings of reproductively: (1) both opponents reproductively active, (2) only the male in reproductive, (3) only the female reproductive, or (4) both opponents non-reproductive. Results showed differences between treatment groups in urine release, current generation, and social behavior. Within reproductive pairings, both the male and female crayfish generated currents and released urine at higher rates then those in other treatment groups. Urine was released most often when opponents were in chelae contact with each other and these releases were often accompanied by anterior current generation. There were few differences in between males and females in utilization of chemical and mechanical signals. Overall, there was recognition of reproductive state and subsequent changes in behavior in both the male and female crayfish. This study provides additional evidence that both males and females are affected by their own reproductive state and the reproductive state of conspecifics.

Committee: Paul Moore (Advisor) Subjects: