Institutional Repository

The University of Houston Institutional Repository (UHIR) collects, preserves and distributes scholarly output and creative works produced by the University of Houston community. UHIR provides free and open online access to the university’s research and scholarship, including electronic theses and dissertations.


Recent Submissions

The machine without the ghost: Early interactive television in Japan
(Convergence: The International Journal of Research into New Media Technologies, 2021-01-29) Rodwell, Elizabeth A.
This article is part of an ongoing ethnography of the Japanese television industry focusing on its attempts to experiment with live, interactive content that was manipulable via smart devices, laptops, and remote controls. Based on 18 months of fieldwork in the Japanese television industry in four major TV network offices and two production companies, it also incorporates interviews with more than 30 broadcast company employees. I use two case studies of early interactive television programming to discuss the strategies producers have used to create community and promote identification among audiences of these shows: ‘Arashi Feat. You’ was a live music event that courted a large audience through the involvement of a massively popular boy band and promoted the idea of ‘turning viewers into users’ by allowing them to play musical instruments along with the band. ‘The Last Award’ allowed participants to submit and evaluate each other’s videos live through a dedicated user interface. Through these examples, I argue that participation alters the nature of television spectacle and results in changes to the way producers address and inscribe audiences as cocreators of content. The rhetoric used by interactive television accordingly defaults to ‘we’ and ‘us’ and features accessible and relatable celebrities as surrogates for the audience.
Liver X Receptor Ligand GAC0001E5 Downregulates Antioxidant Capacity and ERBB2/HER2 Expression in HER2-Positive Breast Cancer Cells
(2024-04-25) Premaratne, Asitha; Basu, Shinjini; Bagchi, Abhinav; Zhou, Tianyi; Feng, Qin; Lin, Chin-Yo
The HER2-positive subtype accounts for approximately one-fifth of all breast cancers. Insensitivity and development of acquired resistance to targeted therapies in some patients contribute to their poor prognosis. HER2 overexpression is associated with metabolic reprogramming, facilitating cancer cell growth and survival. Novel liver X receptor (LXR) ligand GAC0001E5 (1E5) has been shown to inhibit cancer cell proliferation by disrupting glutaminolysis and inducing oxidative stress. In this study, HER2-positive breast cancer cells were treated with 1E5 to determine their potential inhibitory effects and mechanisms of action in HER2-positive breast cancers. Similar to previous observations in other cancer types, 1E5 treatments inhibited LXR activity, expression, and cancer cell proliferation. Expression of fatty acid synthesis genes, including fatty acid synthase (FASN), was downregulated following 1E5 treatment, and results from co-treatment experiments with an FASN inhibitor suggest that the same pathway is targeted by 1E5. Treatments with 1E5 disrupted glutaminolysis and resulted in increased oxidative stress. Strikingly, HER2 transcript and protein levels were both significantly downregulated by 1E5. Taken together, these findings indicate the therapeutic potential of targeting HER2 overexpression and associated metabolic reprogramming via the modulation of LXR in HER2-positive breast cancers.
The Potential Reversible Transition between Stem Cells and Transient-Amplifying Cells: The Limbal Epithelial Stem Cell Perspective
(2024-04-25) Verma, Sudhir; Lin, Xiao; Coulson-Thomas, Vivien J.
Stem cells (SCs) undergo asymmetric division, producing transit-amplifying cells (TACs) with increased proliferative potential that move into tissues and ultimately differentiate into a specialized cell type. Thus, TACs represent an intermediary state between stem cells and differentiated cells. In the cornea, a population of stem cells resides in the limbal region, named the limbal epithelial stem cells (LESCs). As LESCs proliferate, they generate TACs that move centripetally into the cornea and differentiate into corneal epithelial cells. Upon limbal injury, research suggests a population of progenitor-like cells that exists within the cornea can move centrifugally into the limbus, where they dedifferentiate into LESCs. Herein, we summarize recent advances made in understanding the mechanism that governs the differentiation of LESCs into TACs, and thereafter, into corneal epithelial cells. We also outline the evidence in support of the existence of progenitor-like cells in the cornea and whether TACs could represent a population of cells with progenitor-like capabilities within the cornea. Furthermore, to gain further insights into the dynamics of TACs in the cornea, we outline the most recent findings in other organ systems that support the hypothesis that TACs can dedifferentiate into SCs.
Analysis and design of a traveling-wave array of vertical monopoles in a substrate
(1988) Kwok, Sai Chong; Jackson, David R.; Long, Stuart A.; Wilton, Donald R.; Su, Wu-Pei
This thesis presents an analysis and design technique for a traveling-wave array of monopoles embedded within a substrate, fed by a meandering stripline. First, a Green's function for a vertical Hertzian dipole in a single-layered substrate is derived using reciprocity. The Green's function for a ring of vertically directed currents parallel to the ground plane in a substrate is then derived. This is used in an exact kernel formulation of the self impedance of a monopole, which is computed using a variational formula with an assumed piecewise sinusoidal current on the monopole. Both real-axis and deformed path methods are investigated to compute the resulting Sommerfeld integrals, while a branch-cut integration technique is used to evaluate the mutual impedance between monopoles in the array. A Bloch analysis is then used to analyze the structure, which can be approximated as a periodically loaded transmission line, with the loads being the active impedances of the monopoles presented to the stripline. Design principles and procedures are presented for arrays with constant attenuation. Concrete design examples are given. The radiation pattern of the array is also derived, based on the far-held pattern of a single monopole, obtained using reciprocity and plane-wave theory. A ten-element array with constant attenuation is built and tested for experimental verification of the theory.
Geometric analysis for the primitive-based three-dimensional object recognition
(1988) Hatem, Hmam; Dhawan, Atam P.; Anderson, Wallace L.; Rajaram, Navaratna S.
The objective of this thesis is to provide an existing knowledge-based three- dimensional object recognition system with the geometric reasoning necessary for a three- dimensional interpretation of a scene. The actual geometric analysis lies somewhere in the intermediate-level of the system. The system starts by extracting the features and builds relational knowledge between them. Difficulties of edge linking and vertex detection are circumvented by a new technique of gap filling. Next, geometric analysis, using the vanishing point approach, was found to provide the best approximation of the object sizes, and also recover the camera parameters and the depth information lost by the imaging process. This information is embedded in a framelike structure and forwarded to the high- level system for the purpose of image interpretation. Finally, computed results are compared with experimental data and are found to be in close agreement. Concluding remarks suggest further improvements in edge linking that will allow the consideration of a larger class of gap types.