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Title: ³H-ouabain binding and sodium-pump activity measured in myocytes isolated from guinea-pig heart
Creator: Stemmer, Paul
Date: 1986
Collection: Electronic Theses & Dissertations

Title: ²⁰Mg beta decay and the ¹⁵O(alpha, gamma)¹⁹Ne(p, gamma)²⁰Na reaction sequence in Type I x-ray bursts
Creator: Glassman, Brent
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Constraining the ¹⁵O(alpha, gamma)¹⁹Ne(p, gamma)²⁰Na reaction rate is critically important for accurately simulating x-ray burst light curves, our only x-ray burst observable from Earth. Both the ¹⁵O(alpha, gamma)¹⁹Ne(p, gamma) and )¹⁹Ne(p, gamma)²⁰Na reaction rates have been studied using a multitude of experimental techniques, yet only upper limits had been determined at the outset of the present work. The ¹⁵O(alpha, gamma)¹⁹Ne(p, gamma) reaction in particular has been singled out as the...
Show moreConstraining the ¹⁵O(alpha, gamma)¹⁹Ne(p, gamma)²⁰Na reaction rate is critically important for accurately simulating x-ray burst light curves, our only x-ray burst observable from Earth. Both the ¹⁵O(alpha, gamma)¹⁹Ne(p, gamma) and )¹⁹Ne(p, gamma)²⁰Na reaction rates have been studied using a multitude of experimental techniques, yet only upper limits had been determined at the outset of the present work. The ¹⁵O(alpha, gamma)¹⁹Ne(p, gamma) reaction in particular has been singled out as the most important reaction rate of all currently unknown rates to measure. Utilizing the beta decay of ²⁰Mg to populate ²⁰Na excited states, we further constrain the ¹⁹Ne(p,gamma)²⁰Na reaction rate by searching for gamma decays from the most important resonance at E_x=2647 keV. Additionally, by populating ²⁰Na excited states high above the proton threshold, we populate the most important ¹⁹Ne resonance for measuring the ¹⁵O(alpha, gamma)¹⁹Ne(p, gamma) reaction rate at E_x=4.03 MeV. Herein, the results of this study are reported including: The full ²⁰Mg beta-delayed gamma ray spectrum and decay scheme; the upper limit on the beta decay feeding of the ²⁰Na 2647 keV state; the Doppler broadening analysis of nine gamma ray peaks from six excited states in ¹⁹Ne; the intensity of ²⁰Mg(beta,p,gamma) to the 4.03 MeV state in ¹⁹Ne; the measurement of the ²⁰Na excitation energy at 7.44 {+0.25_{-0.22 MeV feeding the 4.03 MeV state in ¹⁹Ne; and the measurement of the center of mass proton energy for the feeding of the important 4.03 MeV state in ¹⁹Ne at 1.23 {+0.25_{-0.22 MeV.
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Title: ¡Palenque! : Cross Cultural Exchange among Indigenous and African Peoples in 17th Century Veracruz, Mexico
Creator: Ramirez, Christian Valentin
Date: 2021
Collection: Electronic Theses & Dissertations
Description: With the arrival of 16th century Spanish migrants to the Americas came new geopolitical identities, racial and cultural hierarchies, and the transformation of social relationships between and among Indigenous communities in Mesoamerica. The Spanish were accompanied by both free and enslaved Africans who transformed the social, cultural, and racial structures of what would later become New Spain. In the context of this historical reality, this dissertation will explore two Afro-Indigenous...
Show moreWith the arrival of 16th century Spanish migrants to the Americas came new geopolitical identities, racial and cultural hierarchies, and the transformation of social relationships between and among Indigenous communities in Mesoamerica. The Spanish were accompanied by both free and enslaved Africans who transformed the social, cultural, and racial structures of what would later become New Spain. In the context of this historical reality, this dissertation will explore two Afro-Indigenous palenques, or self-liberated settlements, by the names of San Lorenzo de los Negros (Yanga) and Nuestra Señora de Guadalupe de los Morenos de Amapa (Mandinga), using a case study approach that combines analysis of primary archival data and secondary literary sources. By exploring self-liberated communities, I will reconstruct a narrative about Afro-Indigenous alliances and their multiple forms of collective resistance against their colonial conditions. The goal is to historicize the African presence as they coalesced with the Indigenous world in New Spain. Additionally, my goal is to demonstrate how European modernity was a key operating ideology in the assignment of their racial/ethnic identities.This dissertation examines the following: 1) investigates and trace the historical processes that made colonial Veracruz a location of cross-cultural exchange; 2) to examines how two distinct colonized groups adapted themselves to their new social relations initiated by Spanish colonialism in order to form their respective palenques; 3) explore how the Spanish racialization project reorganized the racial/ethnic identities of its’ subjects for colonial stability. Overall, this dissertation addresses the literary gap in Sociology and Chicano/Latino Studies concerning the social processes that created the need for palenques during the colonial Mexican era.
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Title: a synthetic medium for microbiological assay of riboflavin, pantothenic acid, biotin, nicotinic acid, pyridoxine and folic acid
Creator: Hyma, Andrew M.
Date: 1945
Collection: Electronic Theses & Dissertations

Title: [FeFe]-hydrogenase substrate transport mechanisms and investigation of algal hydrogen metabolism
Creator: Cornish, Adam
Date: 2012
Collection: Electronic Theses & Dissertations
Description: The global population has recently exceeded 7 billion people and the demand for energy continues to expand as the number of industrialized countries grows. Currently, the energy economy is dominated by the utilization of polluting and non-renewable fossil fuels. Both the collection and use of petroleum-based fuels is destructive to the environment and is not sustainable over a long time-scale, which justifies the investigation into the development of renewable, alternative fuels. Of the...
Show moreThe global population has recently exceeded 7 billion people and the demand for energy continues to expand as the number of industrialized countries grows. Currently, the energy economy is dominated by the utilization of polluting and non-renewable fossil fuels. Both the collection and use of petroleum-based fuels is destructive to the environment and is not sustainable over a long time-scale, which justifies the investigation into the development of renewable, alternative fuels. Of the various fuels that have been proposed, molecular hydrogen (H₂) in particular holds great promise as a clean-burning fuel capable of supplementing the current energy economy, especially as the combustion of H₂ generates only water vapor as by-product. H₂ can be generated via a number of chemical processes, but current H₂ technologies either require fossil fuels as inputs or are energy-inefficient. The biological production of H₂, however, has garnered a great deal of interest because microorganisms are able to drive H₂ synthesis using energy derived from both light and dark fermentative metabolisms. This manner of production does not depend on mining non-renewable resources and microbes can be cultured at the industrial scale without competing with arable land needed for agriculture. H₂ evolution in these microorganisms is dependent on nitrogenases and/or hydrogenases, enzymes which utilize unique metal centers for catalysis. Hydrogenases have been of particular interest for industrial-scale H₂ production because these enzymes are found in a diverse array of organisms and require only protons and electrons as substrates. In particular, [FeFe]-hydrogenases have very high turnover numbers and catalysis can be coupled to photosynthesis. Unfortunately, these enzymes are inactivated by molecular oxygen (O₂), and a number of studies have therefore attempted to engineer O₂-tolerant hydrogenases. However, engineering enzymes to introduce optimal qualities has been impeded by an incomplete understanding of the overall reaction mechanism. Substrate (protons, electrons, and ₂) transport is essential to hydrogenase activity, yet relatively little information is available regarding the intraprotein transport of substrate in [FeFe]-hydrogenase. I focused my investigation on identifying and testing pathways important for substrate transport between the enzyme surface and the active site in the Clostridium pasteurianum [FeFe]-hydrogenase. I have elucidated a key pathway for proton transport and confirmed that two iron-sulfur clusters are essential in an electron transfer relay, contributing to the overall characterization of [FeFe]-hydrogenase activity. Green algae utilize [FeFe]-hydrogenases to catalyze H₂ production using reducing equivalents derived from photosynthesis and these enzymes are an integral component of anaerobic metabolism in these microalgae. I explored the H₂ production capabilities of a multicellular green alga, Volvox carteri, and characterized two hydrogenases likely responsible for this activity. In addition, a unique hydrogenase gene cluster discovered within the Volvox carteri genome provided interesting hints into the origin of [FeFe]-hydrogenase in green algae.
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Title: [Delta]2079-tetrahydrocannabinol-mediated suppression of the Interferon-alpha (IFNalpha) response by plasmacytoid dendritic cells and IFNalpha-mediated activation of T cells in healthy and human immunodeficiency virus (HIV) infected human subjects
Creator: Henriquez, Joseph Edgar
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Δ9-tetrahydrocannabinol (THC) is the primary psychoactive cannabinoid congener in Cannabis sativa and is a well characterized modulator of immune activation. In murine models, treatment with THC can exacerbate viral and bacterial infection, in part, by suppression of the inflammatory cytokine response. One of the key classes of cytokines suppressed by THC is type I interferons (IFN), a group of cytokines consisting of IFNα and IFNβ. The primary source of IFNα during acute antiviral immune...
Show moreΔ9-tetrahydrocannabinol (THC) is the primary psychoactive cannabinoid congener in Cannabis sativa and is a well characterized modulator of immune activation. In murine models, treatment with THC can exacerbate viral and bacterial infection, in part, by suppression of the inflammatory cytokine response. One of the key classes of cytokines suppressed by THC is type I interferons (IFN), a group of cytokines consisting of IFNα and IFNβ. The primary source of IFNα during acute antiviral immune responses is the Plasmacytoid Dendritic Cell (pDC), which can secrete 1000-fold more IFNα than other circulating peripheral blood mononuclear cells (PBMC). Paradoxically, patients infected with human immunodeficiency virus (HIV), a chronic viral infection that causes immunodeficiency via infection and depletion of CD4+ T cells, have fewer circulating pDC with a reduced capacity to secrete IFNα. Furthermore, circulating pDC number has been correlated with CD4+ T cell number and treatment with IFNα can reduce HIV-mediated CD4+ T cell depletion. Conversely, hyperactivation of pDC is associated with T cell exhaustion and is implicated in HIV-associated neurocognitive disorders (HAND). Interestingly, many HIV patients utilize medicinal cannabinoids to combat the effects of chronic HIV infection. The focus of this project was to determine if IFNα-mediated stimulation of T-cells can be suppressed by THC by testing the following hypothesis: THC will suppress TLR-9-dependent activation of pDC, subsequent efficacy of pDC-mediated T cell activation, and CD8+ T cell-mediated activation of astrocytes. These studies revealed that CpG-ODN-induced IFNα secretion and expression of CD83, a costimulatory molecule, by pDC is suppressed by THC in a concentration dependent manner. Furthermore, key intracellular signaling events required for inflammatory cytokine secretion by pDC were suppressed by treatment with THC and CBR2-specific agonists in pDC from healthy donors. Additionally, pDC from HIV+ donors were more sensitive to THC-mediated suppression than pDC from healthy donors. Treatment with THC also inhibited IFNα-mediated activation of CD4+ and CD8+ T cells from healthy and HIV+ donors. Specifically, treatment with THC diminished IFNα-induced IL-7R expression, cognate signaling, and subsequent proliferation. Interestingly, and in contrast to the results in pDC, T cells from HIV+ donors were less sensitive to the suppressive effects of THC. Finally, stimulation by CD3/CD28/IFNα induced the secretion of IFNγ and TNFα by CD8+ T cells from healthy donors. Further, IFNγ and TNFα induced secretion of inflammatory cytokines by U251 astrocytes. Coculture of CD8+ T cells with U251 astrocytes and direct stimulation of U251 astrocytes with recombinant TNFα and IFNγ revealed that treatment with THC reduced both the activation and secretion of cytokines from CD8+ T cells and the subsequent cytokine-mediated stimulation of the U251 astrocytes. Collectively, these studies have provided evidence for the use of cannabinoids in ablating the type of neuroimmune interactions which can lead to HAND by demonstrating that THC can suppress the activation of pDC, and subsequent activation of T cells and astrocytes.
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Title: [Delta]2079-tetrahydrocannabinol suppresses human monocyte activation and monocyte-mediated astrocyte inflammation : implications for HIV-associated neuroinflammation
Creator: Rizzo, Michael Denton
Date: 2019
Collection: Electronic Theses & Dissertations
Description: A hallmark of human immunodeficiency virus (HIV) infection is chronic immune activation and is believed to be one of the major contributors to neuroinflammation and HIV-associated neurocognitive disorder (HAND). Circulating activated monocytes, including those that are CD16⁺, have been implicated in HIV-associated neuroinflammation. These activated monocytes become infected with HIV in the periphery, cross the blood-brain barrier (BBB) and release inflammatory factors, HIV virions and viral...
Show moreA hallmark of human immunodeficiency virus (HIV) infection is chronic immune activation and is believed to be one of the major contributors to neuroinflammation and HIV-associated neurocognitive disorder (HAND). Circulating activated monocytes, including those that are CD16⁺, have been implicated in HIV-associated neuroinflammation. These activated monocytes become infected with HIV in the periphery, cross the blood-brain barrier (BBB) and release inflammatory factors, HIV virions and viral proteins. These factors lead to HIV infection and activation of brain-resident cells, including microglia and astrocytes, driving a pro-inflammatory environment in the brain. Ultimately, these processes contribute to neuronal dysfunction and death, ultimately resulting in cognitive decline in up to 50% of the HIV-infected population. Cannabis is widely used by the HIV-infected population at an estimated prevalence of 23-56% in the United States. [Delta]2079-Tetrahydrocannabinol (THC) and cannabidiol (CBD), two major constituents of cannabis, are known to have immune suppressive and anti-inflammatory properties. The overall objective of this project was to determine whether the cannabinoids, THC and CBD, could suppress monocyte activation and monocyte-mediated astrocyte inflammation, which are key processes implicated in chronic neuroinflammation and HAND. Herein, it is shown that HIV-infected donors using cannabis displayed a lower level of circulating activated (CD16⁺) monocytes and plasma IP-10 compared to non-using HIV-infected donors. Furthermore, in vitro studies revealed that THC but not CBD suppressed monocyte expression of CD16 and secretion of IP-10, suggesting that THC is the major cannabinoid in cannabis promoting the anti-inflammatory effects. To determine whether activated monocytes could promote inflammatory functions of brain-resident glial cells, we developed a human co-culture system utilizing primary monocytes and cell-line/primary fetal astrocytes with viral-related stimulators (IFNa a0333nd a TLR7 agonist - R837). Monocytes, together with IFNa a0333nd/or R837, promoted astrocyte secretion of MCP-1, IL-6 and IP-10. Furthermore, monocyte-derived IL-1v0333 was critical for astrocyte secretion of pro-inflammatory factors, as neutralization of IL-1v0333 strongly hampered the astrocyte response, while direct addition of recombinant IL-1v0333 to astrocyte monocultures mimicked the actions of monocytes. In vitro THC treatment of the R837-stimulated co-culture resulted in decreased astrocyte production of MCP-1 and IL-6, while CBD increased IL-6 production and had no effect on MCP-1 production. With the use of separate monocyte and astrocyte monocultures, THC and CBD were shown to directly target both cell types. Interestingly, THC and CBD were both shown to decrease the percent of astrocytes producing IL-6 and MCP-1, which for THC, is concordant with the co-culture observation. However, the CBD-mediated decrease in IL-6 and MCP-1 production in the astrocyte monoculture differed from the observations in the CBD-treated co-culture. Our findings were explained when THC and CBD were shown to suppress and augment monocyte production of IL-1v0333, respectively. Furthermore, the CBD-mediated augmentation of monocyte-derived IL-1v0333 was able to override the direct CBD suppression on the astrocytes. Collectively, THC but not CBD, impairs monocyte activation and monocyte-driven astrocyte inflammatory responses. In the context of HAND, cannabis use, in particular THC, may decelerate monocyte processes that are implicated in neuroinflammation and cognitive dysfunction.
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Title: Zymogen granule membrane phosphorylation and glycoprotein topology in the exocrine pancreas
Creator: Lewis, Douglas S.
Date: 1977
Collection: Electronic Theses & Dissertations

Title: Zygosporogenesis in Zygorhynchus heterogamus, and zygosporogenesis and sporangiosporogenesis in Mycotypha africana
Creator: Edelmann, Richard Edward
Date: 1994
Collection: Electronic Theses & Dissertations

Title: Zwitterionic excited states of the delta-manifold of quadruply bonded metal dimers
Creator: Engebretson, Daniel Scott
Date: 1998
Collection: Electronic Theses & Dissertations

Title: Zoo visitor satisfaction with animal visibility
Creator: Couch, Ashley S.
Date: 2013
Collection: Electronic Theses & Dissertations
Description: Millions of people visit zoos on an annual basis but we know very little about zoo visitor satisfaction with animal visibility; a lack of animal visibility may negatively impact a zoo visit. This study attempts to determine the overall satisfaction of zoo visitors, their satisfaction with animal visibility, and how important they consider animal welfare and animal visibility. Also, this study examines how often visitors expect the animals to be visible. Finally, wildlife tourists and their...
Show moreMillions of people visit zoos on an annual basis but we know very little about zoo visitor satisfaction with animal visibility; a lack of animal visibility may negatively impact a zoo visit. This study attempts to determine the overall satisfaction of zoo visitors, their satisfaction with animal visibility, and how important they consider animal welfare and animal visibility. Also, this study examines how often visitors expect the animals to be visible. Finally, wildlife tourists and their satisfaction with animal visibility in the wild is compared to a zoo setting. These questions will be analyzed between an array of demographic groups treated as the dependent variables (men vs. women, zoo members vs. non members, age, income, presence of children, weekday vs. weekend visitors, education level) or other visitor features (if they feel the zoo is a good value, feel animals need a hiding place out of view of the zoo visitors, visit frequency). Nearly 500 zoo visitors at two zoos completed an exit survey. T-tests were used to find statistical significance. The results show that most zoo visitors are very satisfied with their zoo experience but there were some statistically significant differences found. Overall, the value of the zoo, zoo membership, and visit frequency were found to have significant differences in some of the survey questions. Wildlife tourists were found to have higher expectations of visibility in a captive setting. The results differed between the two zoos which could be due to the features of each zoo, unique visitor experiences, or even outside factors such as mood. Overall, zoo administrators can learn more about visitor satisfaction and expectations about their visit from this type of research to ensure a positive experience for their visitors and welfare for the animals.
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