Master of Science, The Ohio State University, 2006, Graduate School

Committee: Not Provided (Other) Subjects:

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

Committee: Not Provided (Other) Subjects: Agriculture

Doctor of Philosophy (PhD), Wright State University, 2010, Computer Science and Engineering PhD

Three dimensional integration-based geometric visualization is a very powerful tool for analyzing flow phenomena in time dependent vector fields. Streamlines in particular have many perceptual benefits due to their ability to provide a snapshot of the vectors near key features of complex 3D flows at any instant in time. However, streamlines do not lend themselves well to animation. Subtle changes in the vector field at each time step lead to increasingly large changes between streamlines with the same seed point the longer they are integrated. Path lines, which show particle trajectories over time suffer from similar problems when attempting to animate them. Dynamic deformable objects in the flow domain also complicate the use of integration-based visualization. Current methods such as streamlines, path lines, streak lines, particle advection and their many conceptual and higher dimensional variants produce undesirable results for this kind of data when the most important flow phenomena occurs near and moves with the objects. In this work I present methods to handle both of these problems. First, the flowing seed point algorithm is introduced, which visually captures the perceptual benefits of smoothly animated streamlines and path lines by generating a series of seed points that travel through space and time on streak lines and timelines. Next, a novel dynamic seeding strategy for both streamlines and generalized streak lines is introduced to handle deformable moving objects in the flow domain in situations where static seeding objects fail for most time steps. These two methods are then combined in order to visualize the instantaneous direction and orientation of a flow which results from flapping objects in a fluid. Initial tests are performed with a single rigid flapping disk. Further tests were performed on a more complex biologically inspired CFD simulation of the deformable flapping wings of a dragonfly as it takes off and begins to maneuver. For this test (open full item for complete abstract)

Committee: Thomas Wischgoll PhD (Advisor); Yong Pei PhD (Committee Member); Arthur Goshtasby PhD (Committee Member); Haibo Dong PhD (Committee Member); Joerg Meyer PhD (Committee Member) Subjects: Computer Engineering; Computer Science

Doctor of Philosophy, The Ohio State University, 2004, Horticulture and Crop Science

Treating seeds with growth regulators may be a suitable method for controlling plug height of selected ornamental and horticultural plants. Soaking seeds in 50-1000 mg/L paclobutrazol solutions reduced plug growth in verbena (Verbena x hybrida Voss., cv. Quartz White), pansy (Viola wittrockiana, cv. Bingo Yellow Blotch), salvia (Salvia splendens, cv. Vista Red), marigold (Tagetes patula L., cv. Bonanza Gold), dill (Anathemum graveolens, cv. Fernleaf), and cucumber (Cucumis sativus, cv. Poinsett 76SR). When treating seeds with growth regulators, seedling emergence was delayed and reduced in verbena, pansy, salvia, dill, but not cucumber or marigold. Osmopriming or coating verbena seeds with 10-500 mg/L paclobutrazol were associated with 30-93% or 86-100% reduction in seedling emergence, respectively. Storing paclobutrazol-soaked seeds in a cold chamber for 22 months did not affect marigold growth reduction rates and seedling emergence. Soaking celosia (Celosia cristata, cv. New Look) seeds in 50-1000 mg/L paclobutrazol solutions was associated with negligible reduction in seedling growth. Soaking verbena or marigold seeds in 10-500 mg/L paclobutrazol solutions for 5-180 min did not reduce seed viability (tetrazolium test), but did reduce respiration and heat production rates in seeds. Reductions in seedling emergence and reduced respiration rates in paclobutrazol-treated seeds indicate that paclobutrazol imposed dormancy in verbena seeds. Washing restored rates of respiration and heat production in verbena and marigold seeds. Seed coat morphology or hilum size in verbena, celosia, marigold, or cucumber could not be associated with seedling growth response to treating seeds with growth regulators. Paclobutrazol concentration in the seed coats was higher than in the rest of the seed after soaking cucumber seeds in 1000-4000 mg/L paclobutrazol solutions. Total fruit yield and fruit size in cucumber were reduced when fruits were collected on plants grown from seeds soake (open full item for complete abstract)

Committee: Claudio Pasian (Advisor) Subjects: Agriculture, General

Master of Science, The Ohio State University, 1974, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 2008, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1979, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1916, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 2023, Food Science and Technology

Sunflower seeds are a popular snack in many countries such as the United States, China, and Spain. Sunflower seeds were roasted to create desirable aromas from the Maillard and lipid oxidation reactions. Increasing the pH increased the pyrazines but did not affect other volatiles. Adding reducing sugars or whey protein increased most volatiles. Fructose increased 2,5-dimethylpyrazine, 2-methylpyrazine, trimethylpyrazine concentration more than glucose. However, glucose increased furfural concentration more than fructose. Whey concentrate increased volatile levels more than any other treatment. Total Maillard volatiles and Browning index were increased by the same treatments. Sensory indicated that fructose increased desirable aroma the most, followed by whey protein treatments, and both were liked more than the pH 7 control. Optimizing roasting conditions by increasing the pH, reducing sugar and protein content can favor the Maillard reaction conditions increasing the positive aromas associated with roasted sunflower seeds.

Committee: Sheryl Barringer Dr. (Advisor); James Jasinski (Committee Member); Luis Rodriguez-Saona Dr. (Committee Member) Subjects: Chemistry; Food Science

Master of Science (MS), Ohio University, 2021, Plant Biology (Arts and Sciences)

Due to their sessile nature, plants rely on a variety of vectors, such as wind and animals, to distribute their seeds. It was previously assumed that seed dispersal consisted of a single phase, however recent studies have discovered that the seeds of many plants are dispersed by more than one vector in successive stages. Our research demonstrated the occurrence of multi-phase dispersal of forest perennial herb seeds by a species of scatter hoarding rodent in a temperate deciduous forest. In order to determine the effectiveness of Peromyscus leucopus (White-footed mice) as a secondary dispersal agent, we conducted two separate experiments that explored the seed preference, foraging, and hoarding behavior of P. leucopus. We also conducted a germination experiment to determine the suitability of different microsites for perennial forest herb germination. A field experiment designed to assess the ability of P. leucopus to distinguish seed quality and demonstrate preferences based on seed characteristics, found that this species does in fact demonstrate specific preferences based on seed characteristics. Their preference for smaller seeds went against our hypothesis and the expectations of the optimum foraging hypothesis. This animal's behavior regarding seed preference and seed hoarding behavior was further assessed in two separate trials of a tracking experiment utilizing seeds labeled with the radioactive isotope, Iron-59. From this experiment, we 4 were able to demonstrate the occurrence of scatter hoarding by P. leucopus involving four seed species. A spring germination experiment found that scatter hoard microsites are suitable for the germination of forest perennial herb seeds. The combined results from these three experiments demonstrated that P. leucopus has the potential to serve as an effective secondary seed dispersal agent for four species of perennial herbs that are native to the temperate deciduous forests of southeastern Ohio. Alt (open full item for complete abstract)

Committee: Glenn Matlack (Advisor); Harvey Ballard (Committee Member); Rebecca Snell (Committee Member) Subjects: Plant Biology

Ph.D., Antioch University, 2019, Antioch New England: Environmental Studies

Since the beginning of agriculture, seeds have been cultivated, saved, and exchanged by farmers each year to ensure the success of future crops adapted to local environments. Yet, over ninety percent of our diverse vegetable and fruit crop varieties have been lost due to the industrialization and commercialization of seeds. Industrial agriculture has caused a great homogenization of crop varieties, but locally adapted seeds and their seed savers do still exist on the fringe, and across the world. There is a small but growing body of research on agri-food networks in Western and developing countries where advocates are working to continue and/or redevelop a stock of locally adapted seed in order to better serve humanity's needs in light of the effects of climate change and corporate interests. Using Actor-Network Theory (ANT), this dissertation explores the seed as it exists within different agri-food networks. First, I explain ANT through a review of agri-food studies literature that utilizes this unique "theoro-methodology." Next, I investigate how the seed exists within traditional, modern alternative, and industrial agricultural networks in order to discover the effects that emerge from actor interactions with the seed in these networks. I then put this knowledge to use in an on-site research project where I conduct an ANT investigation of the Ridge & Hollow Seed Alliance network, located in southeastern Ohio. Important network effects that I discover include saved seed, profit, survival, and what I call "resilience knowledge" - knowledge that is gained at the margins of our food system, outside of the hegemonic industrial agriculture complex. Social-ecological resilience knowledge is being created through local food networks (and especially those that include seed saving and exchange). People, plants, and things - actors in these networks - are creating important resilience memories that might assist the local food movement in establishing itself as a viable alt (open full item for complete abstract)

Committee: Alesia Maltz Ph.D. (Committee Chair); Jean Kayira Ph.D. (Committee Member); Theresa Moran Ph.D. (Committee Member) Subjects: Agriculture; Environmental Studies

Doctor of Philosophy, The Ohio State University, 1987, Graduate School

Committee: Not Provided (Other) Subjects: Agriculture

Doctor of Philosophy, The Ohio State University, 1983, Graduate School

Committee: Not Provided (Other) Subjects: Biology

Doctor of Philosophy, The Ohio State University, 1975, Graduate School

Committee: Not Provided (Other) Subjects: Biology

Doctor of Philosophy, The Ohio State University, 1973, Graduate School

Committee: Not Provided (Other) Subjects: Agriculture

Doctor of Philosophy, The Ohio State University, 1963, Graduate School

Committee: Not Provided (Other) Subjects: Agriculture

Master of Science, The Ohio State University, 2012, Horticulture and Crop Science

Although gene flow between crop and wild relatives is not a new area of study, much can still be learned through the investigation of hybrids between divergent taxon. Most crops exchange alleles with wild and weedy relatives, especially when grown in crop centers of origin. Such gene flow can result in evolutionary consequences for wild populations ranging from genetic erosion and demographic swamping to the evolution of enhanced weediness. All of these scenarios are concerning, since wild populations constitute a breeding pool in which valuable allelic diversity is stewarded and weeds already cause problems in agriculture. Helianthus annuus was domesticated in North America where its cultivated and wild forms have been known to hybridize when grown in proximity. However, cultivated sunflower and its relative, common sunflower, differ in morphology, ecological habit, and life history. For example, dormancy differs between crop and wild sunflower types since it was selected against during domestication, but has remained necessary for maintaining fitness for wild plants. Sunflower has physiological dormancy, but the strength and duration of dormancy differs between wild and crop types. Achenes resulting from hybridization between crop and wild sunflower have been shown to have reduced dormancy compared to wild achenes. Although the introgression of crop alleles into wild populations cannot occur unless the F1 generation survives to reproduce, the dormancy of later generations is important for determining if this trait could provide significant resistance to introgression. The objectives of this work were twofold: to identify how maternal parent and differing crop allele percentages each affect seed germination, dormancy, and mortality. Here, fifteen hybrid crosstypes were created on three different maternal plant types – wild F1 crop-wild hybrid, and crop. Since the pericarp and seed coat of sunflower achenes are maternal tissue, contrasting the three maternal types a (open full item for complete abstract)

Committee: Kristin Mercer Dr. (Advisor); Peter Curtis Dr. (Committee Member); James Metzger Dr. (Committee Member); Emilie Regnier Dr. (Committee Member) Subjects: Agriculture; Physiology; Plant Biology

Master of Science, The Ohio State University, 2011, Food Science and Technology

Pumpkin (Cucurbita pepo and maxima) seeds are uniquely flavored and commonly consumed as a healthy roasted snack. The objective was to determine dominant volatiles in raw and roasted pumpkin seeds, and the effect of seed coat, moisture content, fatty acid ratio, total lipids, reducing sugars and harvest year on volatile formation. Sensory was conducted to evaluate overall liking of seed variety and texture. Seed processing included: extraction from the fruit, dehydration and roasting (150 C). Oil extraction was done using soxhlet method, fatty acid profile using GC-FID and reducing sugars using 3,5 dinitrosalycylic acid reagent and uv spectroscopy. Headspace analysis of seeds was performed by a Selected Ion Flow Tube Mass Spectrometer (SIFT-MS). Volatiles dominating in raw pumpkin seeds were lipid aldehydes, ethyl acetate, 2, 3-butandione and dimethylsulfide. Compounds contributing to roasted aroma include alkylpyrazines, and Strecker and lipid aldehydes. Overall, hull-less seeds had higher volatile lipid aldehydes along with Strecker aldehydes. Seeds dehydrated to a moisture content of 6.5% before roasting had higher initial and final volatile concentrations than seeds starting at 50% moisture. Higher oil content resulted in higher lipid aldehyde formation during roasting and a moderate correlation between FFA ratio and corresponding lipid aldehyde was found. Harvest year (2009 vs. 2010) had a significant impact on volatile formation in hull-less seeds, but not as much as variety differences. No significant correlation was found between reducing sugars and volatile formation. Sensory showed that hull-less seeds were liked significantly more than hulled seeds.

Committee: Sheryl Barringer PhD (Advisor); James Harper PhD (Committee Member); John Litchfield PhD (Committee Member) Subjects: Food Science

MS, Kent State University, 2008, College of Arts and Sciences / Department of Biological Sciences

Populations of plants can vary dramatically in the number of individuals they contain. Small populations are often at greater risk of extinction, making it important to understand why some populations consist of hundreds of plants while others contain fewer than twenty. Factors that affect germination, seedling establishment, growth, or survival will likely have a significant effect on population size. Because plants are continually in contact with the soil environment, such factors likely include interactions with soil microbes, such as fungi, and aspects of soil chemistry and composition. Lobelia siphilitica, an herbaceous perennial plant native to the eastern United States, exhibits a high degree of variation in population size. I sampled soils from 14 populations across Ohio and West Virginia, ranging in size continuously from 30-330 individuals. I have conducted two detailed studies addressing regional variability in soil properties, microbial community composition, and plant-microbe feedback that may explain plant population size variation. The first deals with spatial patterns of soil microbial community composition, and how this organization is affected the presence or absence of this plant species, soil characteristics, and geographic location (Chapter 2). I found that microbial communities found at different microhabitats within the same location can be structured quite differently, and that this may in fact be contributing to the actual soil effect. The second study examines plant-soil feedback and its potential to explain geographic variation in population size in L. siphilitica (Chapter 3). I found regional-scale variation in negative feedback on seed germination, growth, and survival that is likely mediated by biotic components in the soils. The strength of negative feedback was strongly positively correlated with plant population size, suggesting that the combination of negative effects on these plant success traits likely results in the geographic va (open full item for complete abstract)

Committee: Andrea Case (Advisor); Christopher Blackwood (Advisor); Oscar Rocha (Committee Member) Subjects: