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<p> The proper organization of receptors and signal transduction protein complexes of epithelial and neuronal cells is crucial in tissue formation, cellular differentiation and proper overall development and function. Scaffolding proteins are major components involved in protein targeting and protein complex assembly. MAGUK.s, a family of scaffolding proteins with multiple binding domains such as PDZ, SH3 and GUK, are important regulators of cellular polarity by recruiting and assembling signal and cytoskeletal components into large complexes. Cell polarity is established and maintained by the proper formation and placement of cellular junctions, which separate the plasma membrane into two distinct domains: apical and basolateral. Epithelial polarity determinants from the Bazooka, Crumbs and Scribble complexes establish the boundaries between the apical and basolateral membrane domains and situate the adherens junctions (AJ) at the interface between the two domains. In neuronal cells, the organization and polarization of the presynaptic and the postsynaptic membranes is organized by the CASKIVELIIMINTl/Xllalpha complex. Both CASK and VELI also play a role in epithelial cells. </p> <p> Two novel proteins, originally discovered by Far Western overlay assay in Mus musculus, have been identified as additional binding partners of VELI: PALS I and PALS2. Both proteins are MAGUK.s and are thought to compete with CASK for binding VELI via L27 domain dimerization. PALSl, a major component of the Crumbs complex, is essential for the formation of AJ and the establishment of cellular polarity. PALS2 has been shown to co localize with E-cadherin below tight junctions and directly associate with nectin-like molecule-2 (Necl-2) at extra junctional regions, however its function remains unknown. </p> <p> Using Drosophila melanogaster as a model organism, we have identified the potential Drosophila ortholog of P ALS2, termed dP ALS2, and found that it is conserved across other species. We have done extensive sequence analysis of dP ALS2 at the nucleotide and amino acid level and determined the RNA transcript distribution and protein localization. </p> <p> dP ALS2 expression begins around stage 13 in embryonic tissues in a transversestriped pattern in the epithelia and continues in this striped pattern until the end of stage 17. dP ALS2 is expressed in adult tissues but undetectable in larval tissues. Based on homology and the expression pattern, dP ALS2 may play a role in cell adhesion or cell polarity, similar to the mammalian orthologs. However the striped expression pattern of dPALS2 is similar to segment polarity proteins thus implying dPALS2 may play a role in segment polarity. </p> / Thesis / Master of Science (MSc)

Thesis / Master of Applied Science (MASc)

PEA3 is a member of the expanding Ets family of transcription factors. In the adult mouse, PEA3 mRNA is expressed at highest levels in the brain, epididymis and at lower levels in the mammary gland, testes, ovary and uterus. PEA3 mRNA is expressed differentially during mouse embryogenesis and is down-regulated following retinoic acid induced differentiation in mouse embryonal carcinoma cell lines. PEA3 is overexpressed at the transcriptional level in 93% of all HER2/neu positive human breast tumors. The molecular basis for differential transcription of the PEA3 gene is not known. Sequence analysis revealed that the upstream region of the PEA3 gene has characteristics of a CpG island and does not possess a recognizable "TATA" element. Rapid amplification of 5' eDNA ends (5'RACE) reveals that transcription initiates from multiple sites, consistent with the absence of TATA elements. To localize cis-acting sequences required for PEA3 expression, deletions of the putative promoter were placed upstream of a luciferase reporter gene and tested for activity in the FM3A cell line. FM3A cells express substantial levels of PEA3 mRNA and protein, which suggests that all of the factors required for transcription are present in the cells. Transient transfections of 5' and 3' deletion mutants of the PEA3 promoter indicated that the efficiency of the PEA3 promoter depended on both negative and positive cis-elements, located upstream and downstream of the transcription start sites. A DNA fragment containing a region from -3 to +676, relative to the major start site of transcription, was sufficient for maximal promoter activity. Luciferase reporter plasmids containing more 5' flanking sequence had lower activity indicating the presence of silencer elements. To aid the identification of critical sequence elements within the minimal PEA3 promoter, we cloned and sequenced the putative human PEA3 promoter. Comparison of the mouse and human PEA3 DNAs revealed that sequences required for maximal promoter activity in the mouse were highly conserved in the human gene. Furthermore, these conserved sequences corresponded to a variety of consensus binding sites: 6 Sp1, 8 c-ets-1, 3 PEA3, 3 AP-2, 3 MZF-1, 2 MyoD, 2 Ik-1, 2 c/EBPB, 2 oEF-1/USF, 2 HSFI and one of each of the following: AP-4, Ik-2, SRY, CP2, HEN-I, CREB andE47. / Thesis / Master of Science (MS)

Recently scholars involved in narrative analysis seem to have overlooked the role of the narrator and overemphasized that of the readers. They even have different perspectives on the identification of the readers. Whoever the reader is, they place an omnipotent ability onto the reader as the master of interpreting the biblical narratives so that the reader maintains an unchanged position in this field but the narrator loses his/her effect. Such a tendency becomes more problematic in dealing with biblical characterization. With this problem in mind, the principal objective of this dissertation is to demonstrate the dynamic relationship between the narrative themes and characters created by the Lukan narrator rather than the reader in the Infancy Narrative. This study considers the narrator as the main entity who creates the narrative themes, especially in relation to the narrative characters, and presents a model of narrative analysis which has been formalized for the study of the Luke's thematic characterization in the Infancy Narrative (Luke 1-2). The main question of the dissertation is two-fold: 1) how does the narrator characterize his characters for the sake of his narrative themes?; 2) What is the thematic function of the Infancy Narrative in the Lukan Gospel in relation to the narrator's thematization of the characters? In order to answer this question, this study suggests three steps for analyzing the narrative. One is to define the types of characters (on-stage: front ground, foreground, and background; and off-stage: setting and potential), another is to determine narrative themes based upon three dimensions (textual, intertextual, and extratextual), and the other is to observe thematic relations between the characters in the Infancy Narrative and the following parts of the Lukan Gospel. With these steps, this study defmes all characters of the Infancy Narrative and evaluates their thematic roles, and the narrator's themes conveyed by his characters. Lastly, after examining the thematic coherence through narrative characters in the Gospel, this dissertation attests that the Infancy Narrative is a well-designed thematic introduction of the Gospel which establishes the major themes of the Gospel, conveyed by the divine characters (God, the Holy Spirit, and the angel), John, Jesus, and others. / Thesis / Doctor of Philosophy (PhD)

Coal preparation is widely regarded as a cost effective method for reducing the amounts of potentially hazardous air pollutant precursors (HAPPs) that occur as trace elements in the run-of-mine coals. Unfortunately, many existing coal preparation plants are inefficient in removing trace elements because of poor circuit design and inadequate liberation of coal and mineral matter. These problems are often difficult to correct in the absence of characterization data regarding the mineralogical association and washability of trace elements in run-of-mine coals. Therefore, the first step in removing the trace elements through coal preparation is to characterize the modes of association for trace elements in a coal seam. The purpose of this project was to link the occurrence of specific trace elements to the mineralogy and washability characteristics of different eastern U.S. coal seams. Detailed characterization studies were carried out using scanning electron microscopy (SEM) coupled with automated image analysis (AIA) to establish the association between different trace elements and the various components contained in coal. The first step in this analysis required the preparation of 11 different density fractions from a run-of-mine sample of 65 x 100 mesh Pittsburgh No. 8 coal. The samples were then examined using the scanning electron microscope (SEM) to establish the individual mineral constituents contained within each gravity fraction. For comparison, each gravity fraction was also carefully analyzed for trace element content by atomic adsorption spectroscopy (AA). The contribution of various mineral components to the trace element concentrations was determined in the present work using statistical procedures, i.e., individual linear regression and multiple linear regression. After completing the SEM analyses, washability (float-sink) tests were performed on three different coal seams. In this work, several size fractions from each of three different run-of-mine coals were subjected to float-sink testing and release analysis. Because of the overwhelming amount of data, statistical analyses were conducted to show the key relationships identified by this work. The data collected from this study show that trace elements are primarily associated with the mineral matter present in run-of-mine coal. The washability work also shows that the trace elements are concentrated in the heavier specific gravity classes. The characterization work shows that majority of the trace elements are associated with the ash-forming mineral matter and pyrite. The only element found to have a strong association with organic matter was beryllium. The information obtained from this work suggests that a properly designed coal preparation plant can remove substantial amounts of trace elements prior to coal combustion. / Master of Science

Over the past 40 years, several procedures have been proposed for characterizing ideal flotation behavior. These procedures, known as release or tree analysis, generally involve multi-stage flotation in batch, laboratory flotation cells using various combinations of rougher, cleaner, and scavenger configurations. Although some of these procedures have been experimentally compared, there remains considerable controversy as to which approach best approximates the ideal flotation response. In this investigation, modeling and simulation techniques are used in conjunction with experimental studies to compare three procedures commonly used for characterizing flotation behavior. These procedures include timed release analysis, simplified release analysis, and tree analysis. Timed release analysis is shown to produce superior results to simplified release analysis and tree analysis; although simplified release analysis appears to be best suited for locating the "elbow" of the grade-recovery curve. In no case, do any of these techniques approximate a perfect separation. A novel technique, known as reverse release analysis, is described and demonstrated to be superior to the other three procedures. Finally, a theoretical methodology for obtaining the true ideal separation curve is presented. / Master of Science

Direct conversion of solar energy, which is the most powerful and unlimited one among the renewable energy sources / into the electrical energy by the photovoltaic devices, is a promising way of meeting the energy needs of future. Thin film semiconductor materials show great promise for the production of efficient, low-cost solar cell devices. Recently advanced research on thin film photovoltaics in all aspects, has attracted intense attention. Thin film semiconductors for the photovoltaic applications are deposited in large areas by different methods. In this study, deposition and characterization of CuIn1-x GaxSe2 ( CIGS ) semiconductor thin films by thermal evaporation and e-beam evaporation methods were investigated. Material properties and deposition parameters of the thin films are aimed to be optimized for solar cell applications. Structural properties of the deposited CIGS thin films were examined through X-ray diffraction and Energy Dispersive X-ray Analysis. The temperature dependent electrical conductivity, Hall effect and photoconductivity of these samples have been measured between 100 and 400 K. For the optical characterization of CIGS thin films, the transmission measurements have been carried out in the wavelength region of 325-900 nm. The changes in the structural, electrical and optical properties of samples through post-depositional annealing effect were also analyzed.

In the present study, the effect of S and Se substitution on structural, electrical and optical properties of AgGa(Se2-xSx) thin films has been investigated. AgGa(Se0.5S0.5 )2 thin films were prepared by using the thermal evaporation method. X-ray diffraction (XRD) analysis has revealed that the transformation from amorphous to polycrystalline structure took place at about 450 oC. The detailed information about the stoichometry and the segregation mechanisms of the constituent elements in the structure has been obtained by performing both energy dispersive X-ray analysis (EDXA) and X-ray photoelectron spectroscopy (XPS) measurements. AgGaSe2 thin films were deposited by using both electron-beam (e-beam) and sputtering techniques. In e-beam evaporated thin films, the effect of annealing on the structural and morphological properties of the deposited films has been studied by means of XRD, XPS, scanning electron microscopy (SEM) and EDXA measurements. Structural analysis has shown that samples annealed between 300 and 600 oC were in polycrystalline structure with co-existance of Ag, Ga2Se3, GaSe, and AgGaSe2. The variation of surface morphology, chemical composition and bonding nature of constituent elements on post-annealing has been determined by EDXA and XPS analyses. AgGaSe2 thin films were also prepared by using sputtering technique. XRD measurements have shown that the mono-phase AgGaSe2 structure is formed at annealing temperature of 600 oC. The crystal-field and spin-orbit splitting levels were resolved. These levels around 2.03 and 2.30 eV were also detected from the photospectral response measurements. Thin films of Ag-Ga-S (AGS) compound were prepared by using AgGaS2 single crystalline powder and deposition of the excess silver (Ag) intralayer with double source thermal evaporation method. As a consequence of systematic optimization of thickness of Ag layer, Ag(Ga,S) with the stoichiometry of AgGa5S8 and AgGaS2 were obtained and systematic study to obtain structural, electrical and optical properties was carried out.

International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Initial results of wideband channel sounding experiments sponsored by the Advanced Range Telemetry (ARTM) program are presented. Data collected at Edwards EAFB during the Winter 1998-1999, are analyzed in the frequency domain to estimate the number, strength, and delays of the significant multipath reflections observed during the experiments. We observe that the channel is adequately modeled using two or three multipath reflections. The multipath fade events are correlated with recorded bit error rates and transmitter location to provide a comprehensive overview of the channel characteristics. Summaries from two test flights are included where it is seen that the 2- and 3-ray channel models provide excellent models for the data. In general, the 3-ray model captures the essential features of the multipath interference. In this model the first multipath is a strong specular reflection with relative amplitude greater than 0.5 and relative delay in the 30 to 70 ns range. The second multipath is a much weaker reflection with relative amplitude less than 0.5 and relative delay in the 175 to 325 ns range.