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Evolution And Ecology During Domestication In The Neotropical Fruit Tree, Byrsonima Crassifolia (Malpighiaceae), Genevieve Kerry Marie Croft

All Theses and Dissertations (ETDs)

Plant domestication is the process by which people take wild plants into cultivation and shape them over time into reliable food sources enhanced for consumption and propagation via agriculture. It causes genetic, phenotypic, and ecological changes in cultivated populations. This process is frequently studied in domesticated crops. And yet incipiently domesticated taxa, intermediate to wild and domesticated plants, offer unique opportunities to study domestication as it occurs.

In this dissertation, I use the incipiently domesticated Neotropical fruit tree, Byrsonima crassifolia: Malpighiaceae), to study the timing and extent of genetic and ecological changes in a plant with a varied cultivation history …

The Convergence Of Metabolism And Virulence Factor Regulation On Streptococcus Pyogenes Pathogenesis, Zachary Thomas Cusumano

All Theses and Dissertations (ETDs)

Nutrient acquisition is a strong driving force in the evolution of pathogenesis. For many pathogens such as Streptococcus pyogenes, the coordination of metabolism with the expression of virulence factors is necessary for colonization. Previous research examining the regulation of virulence factors in S. pyogenes identified a unique catabolite sensing regulatory pathway composed of the tagatose bis-phosphate aldolase LacD.1. Examination of LacD.1 has determined that while it still maintains its ancestral enzymatic activity its regulation occurs via a mechanism independent of catalysis. Our approach to understanding how S. pyogenes' metabolism contributes to pathogenesis involves both understanding the adaptation of LacD.1 as …

New Mri Techniques For Nanoparticle Based Functional And Molecular Imaging, Lingzhi Hu

All Theses and Dissertations (ETDs)

Although in clinical use for several decades, magnetic resonance imaging: MRI) is undergoing a transition from a qualitative anatomical imaging tool to a quantitative technique for evaluating myriad diseases. Furthermore, MRI has made great strides as a potential tool for molecular imaging of cellular and tissue biomarkers. Of the candidate contrast agents for molecular MRI, the excellent bio-compatibility and adaptability of perfluorocarbon nanoparticles: PFC NP) has established these agents as a potent targeted imaging agent and as a functional platform for non-invasive oxygen tension sensing. Direct readout and quantification of PFC NP can be achieved with fluorine: 19F) MRI because …

Regulation Of Metabolic Stress-Induced Snornas, Benjamin Steel Scruggs

All Theses and Dissertations (ETDs)

Accumulation of excess lipid in non-adipose tissues is associated with oxidative stress and organ dysfunction and plays an important role in diabetic complications. While a number of stress responses have been implicated, the precise molecular mechanisms linking lipid accumulation and cellular dysfunction are not fully understood. To elucidate molecular events critical for lipotoxicity, we used retroviral promoter trap mutagenesis to generate mutant Chinese hamster ovary cell lines resistant to lipotoxic and oxidative stress. This approach uncovered a previously unsuspected role for small nucleolar RNAs: snoRNAs) as critical mediators of lipotoxic cell death.

Herein we show that under lipotoxic conditions, intronic …

Video-Rate Fluorescence Molecular Tomography For Hand-Held And Multimodal Molecular Imaging, Metasebya Solomon

All Theses and Dissertations (ETDs)

In the United States, cancer is the second leading cause of death following heart disease. Although, a variety of treatment regimens are available, cancer management is complicated by the complexity of the disease and the variability, between people, of disease progression and response to therapy. Therefore, advancements in the methods and technologies for cancer diagnosis, prognosis and therapeutic monitoring are critical to improving the treatment of cancer patients.

The development of improved imaging methods for early diagnosis of cancer and of near real-time monitoring of tumor response to therapy may improve outcomes as well as the quality of life of …

Value Divergence In Global Intellectual Property Law, J. Janewa Oseitutu

Faculty Publications

It is a challenge for the United States to adequately protect the interests of its intellectual property industries, especially when U.S. interests are not in line with the social, cultural, and economic goals of other nations. Yet, as a major exporter of intellectual property protected goods, the U.S. has an interest in negotiating effective international intellectual property agreements that are perceived to be legitimate by the state signatories and their constituents. Focusing on value divergence, this article contributes to the growing body of literature on developing a robust but flexible global intellectual property system, arguing that the trade-based approach to …

Role Of Foundations In The Changing World Of Philanthropy: A Houston Perspective, Ronnie Hagerty

Antioch University Dissertations & Theses

From the earliest days of the American nation, philanthropy has had a defining role in leading change. Philanthropy has provided vision and voice for nascent social movements ranging from civil rights and the women’s movement to AIDS research and environmentalism. As the 21st century has moved into its second decade, philanthropy finds itself facing significant pressures that threaten to compromise its ability to innovate and advocate for issues and individuals whose voices cannot be heard over the public rhetoric of the day. Once perceived as the purview of the rich and well connected, modern philanthropy cuts across social, economic, and …

Women's Leadership In Philanthropy: An Analysis Of Six Giving Circles, Deborah A. Witte

Antioch University Dissertations & Theses

Women have played an essential role in the development of philanthropy in the United States. While their giving behavior and financial contributions have been studied extensively, other aspects of their philanthropy-namely leadership-have not been documented as completely. The giving circle-a new trend within philanthropy where groups of individuals pool their money, and through educating themselves about issues in their community, decide together where to award their funds-provides an ideal case for this study, as the majority of giving circle members are women. In order to gain a better understanding of women's leadership, focus groups were conducted with more than 35 …

Leading Deeply: A Heroic Journey Toward Wisdom And Transformation, Richard Warm

Antioch University Dissertations & Theses

This dissertation will explore leadership as a mytho-poetic transformational journey toward self-knowledge, authenticity, and ultimately wisdom; the power to make meaning and give something back to the world in which we live; and the necessity of transformation. I view leadership as a transformative process and a transformational responsibility. As leaders we must undergo our own transformation in order to lead change on a larger scale. The dissertation will be both philosophical and theoretical, exploring how the threads of the hero’s journey, transformation, wisdom, and leadership intertwine. It will also examine the role of education in this process. Education does not …

A Search For Home: Navigating Change In Battlestar Galactica, Kimberly S. Yost

Antioch University Dissertations & Theses

This dissertation explores the various ways in which the multiple leaders portrayed in the science fiction television series Battlestar Galactica (2003-2009) navigate extreme conditions of continual change. In addition, the dissertation contains a discussion of the larger narrative themes of love, forgiveness, redemption, and embracing the Other as principles effective leaders must cultivate. Through an interpretation of this specific popular media text, a deeper emotional sensitivity to and understanding of leadership, positive and negative, during extreme crises is gained. Furthermore, the series serves as a vehicle through which viewers can reflect on and engage in their own self-awareness about issues …

Faculty Work: Moving Beyond The Paradox Of Autonomy And Collaboration, Mark A. Hower

Antioch University Dissertations & Theses

Freedom to pursue one's intellectual interests, known as professional autonomy, is a valued and longstanding faculty tradition. Profound changes in society and the academy, however, suggest new values may be emerging. Collaboration, for example, is increasingly vital to success outside of the academy, and faculty culture, long an individualistic domain, may be shifting in response. This multiple case study explores how faculty members experience the relationship between professional autonomy and collaboration within the context of their department work. Faculty members in four departments were interviewed and both qualitative and simple quantitative data collected. The study found faculty members satisfied with …

Optimization Of Lactic Acid Fermentation Of York Cabbage For The Development Of Potential Probiotic Products, Amit Jaiswal, Shilpi Gupta, Nissreen Abu-Ghannam

Articles

In the present study, York cabbage was used as the sole substrate for the lactic acid (LA) fermentation with Lactobacillus plantarum. York cabbage was blanched at 95°C for 12min to inactivate surface microflora prior to fermentation. To achieve an optimal fermentation condition which would result in higher release of phytochemicals and antioxidant (AO) capacity in the broth, Box-Behnken design integrating a desirability approach was used. A second-order polynomial equation was developed indicating the effect of solute/liquid ratio, agitation rate and fermentation time on desired parameters. The optimized factors were used for fermenting York cabbage to obtain maximum bacterial growth, …

Brewer’S Spent Grain As A Functional Ingredient For Breadsticks, Anastasia Ktenioudaki, Valérie Chaurin, Sofia Reis, Eimear Gallagher

Articles

Brewer’s spent grain (BSG) was evaluated for its potential as a functional baking ingredient. Scanning electron microscopy (SEM) was used to examine the microstructure of BSG and wheat flours. Baked snacks (breadsticks) were prepared using 15%, 25% and 35% BSG and evaluated for their baking quality and fibre and protein content (over a period of 3 months). The addition of BSG altered the baking characteristics of the breadsticks by affecting their structure and texture. The snacks appeared to lack in cellular structure and crispiness. However, they had quite a stable shelf-life, as changes in texture, moisture and aw progressed at …

Structured Growth And Genetic Drift Raise Relatedness In The Social Amoeba Dictyostelium Discoideum, Neil J. Buttery, Chandra N. Jack, Boahemaa Adu-Oppong, Kate T. Snyder, Christoper R L Thompson, David C. Queller, Joan E. Strassmann

Biology Faculty Research

One condition for the evolution of altruism is genetic relatedness between altruist and beneficiary, often achieved through active kin recognition. Here, we investigate the power of a passive process resulting from genetic drift during population growth in the social amoeba Dictyostelium discoideum. We put labelled and unlabelled cells of the same clone in the centre of a plate, and allowed them to proliferate outward. Zones formed by genetic drift owing to the small population of actively growing cells at the colony edge. We also found that single cells could form zones of high relatedness. Relatedness increased at a significantly …

Mind The Gap: A Comparative Study Of Migratory Behavior In Social Amoebae, Owen M. Gilbert, Jennie J. Kuzdzal-Fick, David C. Queller, Joan E. Strassmann

Biology Faculty Research

Social amoebae aggregate to form a multicellular slug that migrates some distance. Most species produce a stalk during migration, but some do not. We show that Dictyostelium giganteum, a species that produces stalk during migration, is able to traverse small gaps and utilize bacterial resources following gap traversal by shedding live cells. In contrast, we found that Dictyostelium discoideum, a species that does not produce stalk during migration, can traverse gaps only when in the presence of other species’ stalks or other thin filaments. These findings suggest that production of stalk during migration allows traversal of gaps that commonly occurs …

Functional Analysis Of Conserved Motifs In The Mechanosensitive Channel Homolog Mscs-Like2 From Arabidopsis Thaliana, Gregory S. Jensen, Elizabeth S. Haswell

Biology Faculty Research

The Mechanosensitive channel of Small conductance (MscS) of Escherichia coli has become an excellent model system for the structural, biophysical, and functional study of mechanosensitive ion channels. MscS, a complex channel with multiple states, contributes to protection against lysis upon osmotic downshock. MscS homologs are widely and abundantly dispersed among the bacterial and plant lineages, but are not found in animals. Investigation into the eukaryotic branch of the MscS family is in the beginning stages, and it remains unclear how much MscS homologs from eukaryotes resemble E. coli MscS with respect to structure, function, and regulation. Here we test the …

Amino Acid Repeats Cause Extraordinary Coding Sequence Variation In The Social Amoeba Dictyostelium Discoideum, Clea Scala, Xiangjun Tian, Natasha J. Mehdiabadi, Margaret H. Smith, Gerda Saxer, Katie Stephens, Prince Buzombo, Joan E. Strassmann, David C. Queller

Biology Faculty Research

Protein sequences are normally the most conserved elements of genomes owing to purifying selection to maintain their functions. We document an extraordinary amount of within-species protein sequence variation in the model eukaryote Dictyostelium discoideum stemming from triplet DNA repeats coding for long strings of single amino acids. D. discoideum has a very large number of such strings, many of which are polyglutamine repeats, the same sequence that causes various human neurological disorders in humans, like Huntington’s disease. We show here that D. discoideum coding repeat loci are highly variable among individuals, making D. discoideum a candidate for the most variable …

'Delivering' Education; Maintaining Inequality. The Case Of Children With Disabilities In Afghanistan, Jean-Francois Trani, Parul Bakhshi, Anand Nandipati

Brown School Faculty Publications

Education for children with disabilities in Afghanistan, particularly disabled girls, continues to lag behind despite laudable efforts of the Ministry of Education to promote universal access for all. The opportunity for education constitutes not just a means of achieving learning outcomes but also a space for social interaction, individual development and psychosocial support, which are paramount in Conflict Affected Fragile States (CAFS). However, many persisting barriers still need to be overcome in Afghanistan to allow education for all and change negative attitudes towards education of children with disabilities. In this paper we argue that viewing education as a basic commodity, …

Decreasing Time To Market For A Medical Device: New Methods For The Product Development Process, Kelly Marie Davis

Doctoral Dissertations

"Through an example, led at a leading medical device company, this dissertation will demonstrate that by applying certain lean principals and tools to the development of a medical device, shortened development times can be obtained. The two papers presented in the dissertation will fill a gap in current literature. Literature presents lean techniques and applications used in many different industries. But, due to the uniqueness of the medical device industry, these general techniques are not ideal. New methods will be used and validated at a medical device company, Covidien. Instead of trying to implement many general lean principals to their …

Modeling Carbon Sequestration In Transition Zone To Optimize Storage Potential, Fang Yang

Doctoral Dissertations

"Shallow aquifers are potential candidates for carbon sequestration because of their wide distribution and low injection cost. Injected CO₂ in a shallow region segregates into two zones according to CO₂ phases within the initial reservoir pressure and the maximum bottom hole pressure: gas zone and transition zone. Transition zone is a better option because of favorable CO₂ properties. This work investigated the CO₂ storage potential in transition zone using the compositional simulator CMG-GEM and a design of experiment software iSIGHT. First, it addressed the basic characteristics of CO₂ sequestration in transition zone, and then modeled CO₂ injection with simultaneous water …

Therapeutic Effects Of N-Acetylcysteine Amide In The Treatment Of Eye Disorders, Joshua W. Carey

Doctoral Dissertations

"The loss of vision from age-related eye diseases now affects over 30 million people in the United States and is expected to reach twice that number within the next couple of decades. Among these disorders, age-related macular degeneration and cataract formation represent the largest percentage of these cases. Therapeutic options available for treating age-related macular degeneration are limited and there is no noninvasive form of treatment for cataracts current available. Several studies have indicated that oxidative stress plays an important role in the pathology of these age-related eye disorders. If oxidative stress is responsible for the initiation and progression of …

Inventing The Sculptor: Leonardo Da Vinci And The Persistence Of Myth, Emily Hanson

All Theses and Dissertations (ETDs)

No abstract provided.

The Feeding Ecology Of Yucatán Black Howler Monkeys (Alouatta Pigra) In Mangrove Forest, Tabasco, Mexico, Leandra Luecke Bridgeman

All Theses and Dissertations (ETDs)

Mangroves are composed of relatively few species of plants specially adapted to tidal inundation and saline conditions. Mangrove communities are not considered ideal environments for most mammals, especially large-bodied arboreal herbivores, because of the low-diversity, and supposedly, low-quality vegetation. In this study, I investigate the diet and behavior of a population of Yucatán black howler monkeys: Alouatta pigra) isolated in mangrove forest on the Pantanos de Centla Biosphere Reserve in Tabasco, Mexico. I focused my research on the relationship between the behavioral ecology of the monkeys and the diversity, distribution, and nutritional content of mangrove plants. After observations and plant …

Dynamic Deformation And Mechanical Properties Of Brain Tissue, Yuan Feng

All Theses and Dissertations (ETDs)

Traumatic brain injury is an important medical problem affecting millions of people. Mathematical models of brain biomechanics are being developed to simulate the mechanics of brain injury and to design protective devices. However, because of a lack of quantitative data on brain-skull boundary conditions and deformations, the predictions of mathematical models remain uncertain. The objectives of this dissertation are to develop methods and obtain experimental data that will be used to parameterize and validate models of traumatic brain injury. To that end, this dissertation first addresses the brain-skull boundary conditions by measuring human brain motion using tagged magnetic resonance imaging. …

Hydrodynamics, Mixing, And Mass Transfer In Bubble Columns With Internals, Mohamed Hamed

All Theses and Dissertations (ETDs)

Bubble columns and slurry bubble columns are considered reactors of choice for a wide range of applications in the chemical, biochemical, and petrochemical industries. Most of the chemical applications of bubble columns include exothermic processes and hence they require some means of heat removal to maintain a steady process. The most practical means for heat removal in these reactors is the utilization of vertical cooling internals since they provide high heat transfer area per reactor volume. However, the effects of these internals on the reactor performance are poorly understood in the open literature. This causes the design of the internals …

Regulation Of Toxoplasma Motility By Calcium-Dependent Protein Kinases, Sebastian Lourido

All Theses and Dissertations (ETDs)

Apicomplexans are protozoan parasites of animals, which must penetrate host cells to find a niche in which to replicate. To humans, they represent the most ubiquitous and deadliest eukaryotic pathogens, including Toxoplasma gondii and Plasmodium spp., the etiological agents of toxoplasmosis and malaria, respectively. A common mechanism enables these parasites to penetrate biological barriers and invade host cells actively, through a process termed gliding motility. This type of motility, unique to apicomplexans, relies on the directional translocation of adhesins via an actomyosin motor complex anchored in a vesicular network underlying the plasma membrane of the parasite. A variety of stimuli …

Natural Killer Cell Recruitment And Activation Following Orthopoxviral Infection, Melissa Anne Pak-Wittel

All Theses and Dissertations (ETDs)

The orthopoxviridae are large, complex DNA viruses with important historical and clinical significance. Members of this genus encode numerous proteins known to subvert the immune response to infection, providing a useful system to probe required host responses for resistance and survival. Natural killer: NK) cells provide an essential innate response to infection through direct lysis of infected cells and cytokine production. The innate anti-viral response following infection is associated with NK cell population expansion in draining LNs, where they are normally a rare population. We have identified mechanisms underlying NK cell expansion following orthopoxviral infection and have examined viral inhibition …

Multi-Contrast Photoacoustic Microscopy, Junjie Yao

All Theses and Dissertations (ETDs)

Photoacoustic microscopy is a hybrid imaging modality with high spatial resolution, moderate imaging depth, excellent imaging contrast and functional imaging capability. Taking full advantage of this powerful weapon, we have investigated different anatomical, functional, flow dynamic and metabolic parameter measurements using photoacoustic microscopy. Specifically, Evans-blue dye was used to enhance photoacoustic microscopy of capillaries; label-free transverse and axial blood flow was measured based on bandwidth broadening and time shift of the photoacoustic signals; metabolic rate of oxygen was quantified in vivo from all the five parameters measured by photoacoustic microcopy; whole cross-sectional imaging of small intestine was achieved on a …

Patterns Of Seasonal Variation In Diet, Abundance, And Movement Of The Scarlet Macaw (Ara Macao) In Southern Belize, Mark Stephen Mcreynolds

Antioch University Dissertations & Theses

This study was conducted in 2008 and 2009 to determine if Scarlet Macaws (Ara macao), in subtropical southern Belize, Central America, are seasonal and elevational migrants and if their movement is influenced by seasonally abundant food. Reports from southern Belize indicated strongly seasonal sightings of macaws (N ≈ 200) in two separate areas of considerable difference in elevation. I monitored plant phenology plots (2 m x 500 m) in low (N = 6) and high (N = 6) elevation areas for a year to compare fruit abundance with macaw sightings in point counts on the plots and nearby. My point …

Life In The Uncanny Valley: Workplace Issues For Knowledge Workers On The Autism Spectrum, Christina H. Rebholz

Antioch University Dissertations & Theses

Many journal articles about autism spectrum disorders have been published. The definition of “high-functioning autism” used in these papers may need to be reconsidered, as a segment of the population may be more skilled than has been historically thought. A percentage of people on the autism spectrum work in a high-paying professional capacity, in industries such as computer technology and health care. Their intellectual capacities allow them to successfully perform the portions of their jobs that require deep technical knowledge. However, they struggle with the cognitive and social issues associated with the autism spectrum, such as: concrete thinking; literal information …