• 1,4-Dioxane Remediation Using a Constructed Wetland

      Ward, William Jackson (The University of Arizona., 2008)
      This research addressed the question whether a constructed wetland system with phytoremediation could successfully uptake 1,4-Dioxane in groundwater and secondary effluent. It further addressed whether open pond storage could successfully treat wetland discharge. The project was located at the University of Arizona's Constructed Ecosystems Research Facility (CERF) in Tucson, Arizona. This two-year field study was motivated by previous laboratory studies which demonstrated the capability of plants to remediate the recalcitrant contaminant 1,4-Dioxane.The study was conducted in two open steel tanks configured to simulate constructed wetlands. The efficacy of 1,4-Dioxane uptake by cottonwood trees was tested in a side-by-side comparison utilizing planted and unplanted tanks. The sub-surface hydraulic conditions were fully characterized by bromide tracer studies. Six experiments were conducted, in which tapwater or secondary effluent was spiked with 5.2 mg/L 1,4-Dioxane and fed to the planted and unplanted (control) tank. The tank discharges were retained in separate open ponds to test if open pond storage would reduce 1,4-Dioxane content. Additional side experiments were conducted to examine the role of volatilization and UV degradation. Comparison of 1,4-Dioxane mass discharge from the planted and the control tank demonstrated an 18-48 percent uptake by the cottonwood trees. Mass balance assessments showed 1,4-Dioxane uptake efficiency was positively correlated to cottonwood transpiration rates in the planted tank. The open pond 1,4-Dioxane measurements demonstrated a 64-85 percent reduction in 1,4-Dioxane concentration due to volatilization during the initial 120 hours pond lapse time. Elimination of 1,4-Dioxane from the ponds followed first order kinetics. Field and laboratory side experiments demonstrated the potential for UV photo degradation of 1-4-Dioxane.
    • 1. Anionic additions to glycosyl iodides 2. Neutral addition of alcohols to glycosyl iodides 3. Glycosyl iodides in solid phase oligosaccharide synthesis

      Hadd, Michael Joseph (The University of Arizona., 1998)
      The usefulness of glycosyl iodides in carbohydrate chemistry has been demonstrated. Both anionic and neutral nucleophiles have been shown to react readily with glycosyl iodides as the glycosyl donor. High yields and stereoselectivity were obtained along with short reaction times. Anionic nucleophiles gave β glycosides selectively, whereas neutral nucleophiles gave α glycosides in the presence of tetrabutylammonium iodide. Initial investigation of the applicability of these glycosidation conditions to solid phase oligosaccharide synthesis has been accomplished.
    • 1. Development of a novel ELISA for the testing of glycobioconjugates as anti-HIV agents 2. Synthesis of potential inhibitors of the HIV entry mechanism 3. Probing the secondary structural characteristics of oligosaccharides utilizing circular dichroism

      McReynolds, Kathrine Dawn (The University of Arizona., 1999)
      AIDS, or acquired immunodeficiency syndrome, is caused by the human immunodeficiency virus (HIV). HIV is a retrovirus that is capable of rapid genetic mutation, which makes the virus and the disease difficult to treat. Several drug therapies are currently available, in the form of viral enzyme inhibitors. Other inhibitors of the viral entry and replication process are being investigated to enhance the drug therapy arsenal. Our research has focused on the development of HIV entry inhibitors. We are working towards the development of novel carbohydrate-based agents that are capable of binding the gp120 protein on the viral surface, such that viral entry into an uninfected host cell is prevented. In order for our research to progress, a qualitative method by which our synthetic compounds could be evaluated for gp120 binding was sought. We have developed a unique ELISA (enzyme-linked immunosorbent assay) that indicates whether or not a compound has binding affinity for the viral protein. A TIRF (total internal reflection fluorescence) microscopy method, has been developed as part of a collaborative effort with the laboratories of Professors Saavedra and O'Brien, to assess active compounds for quantitative equilibrium binding constants to gp120. We have synthesized several carbohydrate-based molecules targeted to one or more of the binding sites on the surface of gp120; the galactosylceramide site, the V3 loop, and the CD4 binding site. Utilizing both the ELISA and TIRF methods, we have succeeded in probing the binding profile of gp120. Circular dichroism studies have also been employed to evaluate the secondary structural characteristics of oligomeric carbohydrate materials. Molecules with helical properties have potential as CD4 binding site inhibitors. The long term goals of this project involve the synthesis and gp120 binding evaluation of novel carbohydrate-based materials to serve as entry inhibitors of the HIV replication process. A possible application of this project lies in the development of compounds capable of binding to more than one site on the protein. A variation of this goal involves the tethering of various compounds with specificities to different sites on gp120, for the purpose of inhibiting multiple binding sites on the protein.
    • 1. Mechanistic studies on the formation of glycosyl iodides 2. Synthesis of amino sugars via glycosyl iodides

      Nguyen, Truc Ngoc, 1972- (The University of Arizona., 1998)
      The synthesis of oligosaccharides remains a challenging task. In our studies, we applied glycosyl iodides to the synthesis of oligosaccharides. The mechanism of formation of glycosyl iodides from anomeric acetates of glucose, galactose and mannose, and 1,2 and 1,6 anhydro sugars were investigated by NMR. Glycosyl iodides were then applied in glycosidation studies and specifically in the synthesis of a precursor to the trisaccharide of Lewis x, a blood group antigen.
    • 1. Synthesis of C-glycoside sulfones via oxirane-thirane exchange 2. Preparation of sialic acid derivatives amenable to solid-phase synthesis 3. Conformational analysis of complex polysaccharides

      Flaherty, Terrence Michael (The University of Arizona., 1997)
      As part of a program directed toward the synthesis of novel glycosyl transferase inhibitors possessing a sugar-CH₂-SO₂-CH₂-SO₂-CH₂-nucleoside structure, β-C-glycoside sulfones have been prepared with high stereoselectivity. Both glucose and fucose derivatives were prepared. Sulfur incorporation was achieved by free radical addition of thiolacetic acid to exocyclic glycals. As part of a program directed toward the preparation of amide-linked sialic acid oligomers, a strategy was developed for the synthesis of sialic acid derivatives possessing either a free amine or a free acid functionality. Solution phase coupling of these monomers using standard peptide coupling techniques resulted in the synthesis of (1 → 5)-amide linked sialic acid dimers. As part of a program directed toward the identification of novel helical structures, the solution phase conformation of the polylactone of colominic acid was examined by NMR and molecular modeling. The two structures generated from molecular modeling that were consistent with the NOE data were both helical.
    • The 11/10th century B.C.E. transition in the Aijalon Valley Region: New evidence from Tel Miqne-Ekron Stratum IV

      Ortiz, Steven Michael (The University of Arizona., 2000)
      Recent deconstructionist trends within Syro-Palestinian archaeology and biblical studies have now converged on the Israelite Monarchy causing two major ceramic reappraisals of the Iron Age I and II Periods. The result is a proposal for a new low chronology in Syro-Palestinian archaeology. These trends are creating more problems than they are solving by naively assuming ceramic change was consistent throughout Syro-Palestine and manipulating the archaeological data to fit the new models. The dissertation addresses the radical archaeological and historical reconstructions of the current trend by focusing on the Iron Age I-II transition in the northern parts of the Philistine coast and Shephelah (foothills)--Aijalon Valley Region. Excavations at Tel Miqne-Ekron provide new evidence for an evaluation of recent chronological proposals and aide in the development of a ceramic corpus of the Aijalon Valley Region. As a border site between the coastal region and the hills, Tel Miqne is an important site to isolate and compare regional variations and the complex socioeconomic variables that pattern the archaeological record. The dissertation is divided into three parts. Part I includes a review of current work in Syro-Palestinian Iron Age research and an overview of ceramic theory development. Part II contains the core database: (1) development of the Tel Miqne Stratum IV typology, and (2) a comparanda, with other sites in the region and attempt to isolate the chronological and spatial patterns of the Iron Age transition (11/10th century B.C.E.). Part III contains the results and interpretations. This study concludes that: (1) ceramic change is not chronologically homogeneous and therefore regional variation must be incorporated in all ceramic analyses; (2) the proposed new Low Chronology for the Iron Age in the southern Levant cannot be supported by the archaeological evidence; and (3) the Aijalon Valley Region reflects the complexity of the Iron Age transition as many ethnic elements and political groups vied for control of the important crossroads and access to coastal ports.
    • 13C and 37Cl characterization of PCE and application to contamination of the Harrison Landfill: Tucson, Arizona

      Rosengreen, Sven Albert. (The University of Arizona., 2000)
      Tetrachloroethene (PCE) contamination of groundwater and soil air underneath Harrison Landfill in Tucson, Arizona, likely occurred by downward vapor phase transport of PCE dumped in the landfill. This study has explored the possibility of using isotopic techniques to better understand this process. The author designed and used a technique for the extraction of PCE vapors from soil air, for 6 13C and 637C1 analysis. It involved collecting PCE vapors by passing soil air through PCE adsorbent traps, then processing and transferring the PCE to a combustion tube. The author also measured for 6 13C and 637C1 values from manufactured trichloroethene (TCE, same as measured by another lab) and PCE samples. An additional experiment measured the 6 13C and 837C1 values of the liquid PCE residual after evaporating various fractions of PCE. 8 13C and 837Cl values of the TCE samples previously described were similar to the earlier values, indicating that 8 13C and 637C1 measurements of solvents (including PCE) were reproducible. Successive evaporation of PCE followed a Rayleigh trend, indicating a values of 1.0006 for carbon and 0.9992 for chlorine. The author simulated the PCE soil vapor sampling in the laboratory, achieving high yields and good separation of PCE. 8 13C values from Harrison soil PCE vapors ranged from — 27.3 to —25.1 0/00 and were within previous values for PCE. 637C1 values were at least 2.3 0/00 higher than any previously reported for PCE samples. 637C1 values for PCE, indicated that either the PCE in Harrison landfill became fractionated in situ, or was already 37C1 rich when dumped at the site.
    • 15-deoxy-delta-12, 14-prostaglandin J2 (15d-PGJ2) Mediated Signaling in Colon Cancer

      Mehta, Dipti J (The University of Arizona., 2006)
      Normal tissue structure and function are maintained by a dynamic interaction between epithelial cells and the stroma consisting of fibroblasts, adipose, vasculature and resident immune cells, and a multitude of cytokines and growth factors. Stroma was usually studied in the background of the malignant lesion, only in recent years researchers have started considering its role before carcinogenic lesions appear. Recent studies have shown that stromal cells and their products can cause the transformation of adjacent cells through transient signaling during phenomena like adipogenesis and inflammation by secreting various cytokines and chemokines into the matrix which can lead to apoptosis resistance, proliferation, mutations etc. Research in the last few years has demonstrated a functional role for stroma in the initiation and progression of breast, colon and prostate carcinomas. In this study effect of adipogenesis and/or inflammation on prostaglandin biosynthesis is investigated and the effects that these prostaglandins can have on epithelial cells is highlighted. This work demonstrates that normal colonic fibroblasts CCD18Co can produce anti-tumorigenic and pro-tumorigenic prostaglandins during adipogenesis and that this signaling is mediated via COX-2 activation. Although deoxycholic acid (DCA), a secondary bile acid that is responsible for inflammation in the gastro-intestinal tract, induces COX-2 signaling in the fibroblasts the downstream signaling of prostaglandin synthases is suppressed. Adipogenesis also leads to an increased polyamine catabolism. Effects of the prostaglandins were studied on various epithelial colon cancer cell lines. It was seen that 15d-PGJ2 causes growth inhibition and apoptosis in all cell lines tested and it was demonstrated that an activated K-RAS suppressed this phenomena. It was also seen that 15d-PGJ2 treatment could induce MAPK signaling and that an activated K-RAS suppressed JNK activation via AKT and MKK4. In conclusion this work reports that colonic fibroblasts can produce anti-tumorigenic factors like 15d-PGJ2 which may then induce apoptosis in epithelial cancer cells. This would be suppressed by an activated K-RAS and at the same time 15d-PGJ2 mediated MAPK signaling could confer a growth advantage for these cells and thus aid in tumor progression.
    • The 150-Hour Rule: How Policy Decisions Affect the Supply of Public Accountants

      McLeod, Martha Lamb (The University of Arizona., 2011-05)
    • 17β Estradiol Decreases Vasodilation at 31°C in Ovariectomized Rats

      Brown, Jessica Nicole (The University of Arizona., 2010-05)
      The purpose of this Honor's Thesis is to investigate rat heat dissipation in correlation with estradiol (commonly referred to as estrogen) at different environmental (ambient) temperatures. The relevance of this study is investigative of post-menopausal hot flushes as a thermoregulatory dysfunction.
    • The 1888 election

      Reed, Raymond Lawrence, 1912- (The University of Arizona., 1938)
    • The 1889 and 1900 Paris Universal Expositions: French masculine nationalism and the American response

      Cooley, Kristin Nicole (The University of Arizona., 2001)
      Universal expositions of the later nineteenth century were opportunities for the host country to reinforce its sense of nationalism and to showcase its technological progress or, read differently, the progress of man. This thesis examines nationhood as defined in terms of masculinity at the 1889 Paris Universal Exposition, which demonstrated French technological, colonial, and artistic superiority over all other nations. This superiority was trumpeted not just through architecture and colonial exhibits, but also through criticism of other countries' artwork, particularly painting and sculpture from the United States. Also discussed is the reaction of American artists to the criticism received in 1889 by producing art at the 1900 Paris Universal Exposition that resonated with masculinity, thereby projecting an enhanced national identity in fine art.
    • The 1979 Iranian revolution: the revolutionary revolution

      Brandis, Dov Asher (The University of Arizona., 2009-05)
    • 1990 Spousal rape occurrence

      Watson, Patti Rae, 1958- (The University of Arizona., 1991)
      The purpose of this study was to (1) determine the number of Spousal Rapes reported to law enforcement agencies of the Tucson Metropolitan Area during 1990, (2) measure expert perceptions regarding the occurrence of Spousal Rape in the Tucson Metropolitan Area during 1990, (3) compare official reports and expert perceptions regarding the occurrence of Spousal Rape, and (4) determine what experts believe to cause under-reporting, if found. The population for this study consisted of 30 experts working with victims of spousal rape. These experts were from 4 categories: human service workers, therapists, attorneys, and researchers. Thirteen spousal rape reports were received by law enforcement agencies in the Tucson Metropolitan Area. Experts believed that spousal rape occurrence was 10-2500 times higher than the number reported. Most reasons for under-reported that were shared by experts pertained to low public awareness regarding the causes for spousal rape. Also presented are conclusions, recommendations, and implications.
    • 1D and 2D Photonic Crystal Nanocavities for Semiconductor Cavity QED

      Richards, Benjamin Colby (The University of Arizona., 2011)
      The topic of this dissertation is photonic crystal nanocavities for semiconductor cavity quantum electrodynamics. For the purposes of this study, these nanocavities may be one dimensional (1D) or two dimensional (2D) in design. The 2D devices are active and contain embedded InAs quantum dots (QDs), whereas the 1D devices are passive and contain no active emitters. The 2D photonic crystal nanocavities are fabricated in a slab of GaAs with a single layer of InAs QDs embedded in the slab. When a cavity mode substantially overlaps the QD ensemble, the dots affect the linewidths of the observed modes, leading to broadening of the linewidth at low excitation powers due to absorption and narrowing of the linewidths at high excitation powers due to gain when the QD ensemble absorption is saturated. We observe lasing from a few QDs in such a nanocavity. A technique is discussed with allows us to tune the resonance wavelength of a nanocavity by condensation of an inert gas onto the sample, which is held at cryogenic temperatures. The structural quality at the interfaces of epitaxially grown semiconductor heterostructures is investigated, and a growth instability is discovered which leads to roughness on the bottom of the GaAs slabs. Adjustment of MBE growth parameters leads to the elimination of this roughness, and the result is higher nanocavity quality factors. A number of methods for optimizing the fabrication of nanocavities is presented, which lead to higher quality factors. It is shown that some fundamental limiting factor, not yet fully understood, is preventing high quality factors at wavelengths shorter than 950 nm. Silicon 1D devices without active emitters are investigated by means of a tapered microfiber loop, and high quality factors are observed. This measurement technique is compared to a cross-polarized resonant scattering method. The quality factors observed in the silicon nanocavities are higher than those observed in GaAs, consistent with our observation that quality factors are in general higher at longer wavelengths.