Synthesis of model oxepin substrates for comparative two electron oxidation studies with cytochrome P450 and cerium ammonium nitrate to investigate benzene metabolism

Two model oxepins were synthesized in an attempt to model the metabolism of benzene in the human liver. 4,5-Benzoxepin was subjected to similar enzyme reactions that the oxepin metabolite itself would encounter if one was exposed to benzene. In addition, a synthesis of 2,3-benzoxepin was completed in order to compare enzyme and non-enzyme catalyzed reactions with that of 4,5-benzoxepin. In an attempt to test the validity of the enzyme reactions, the model oxepins were also reacted with a two single electron oxidizing inorganic salt, cerium (IV) ammonium nitrate (CAN) to see if the intermediates following the enzyme reaction were consistent. Other chemists in the past have postulated that oxepin undergoes further epoxidation in metabolism instead of two single electron oxidations, so a test with dimethyldioxirane (DMDO) was also performed on the model oxepins to observe if their products closer matched the enzyme reactions. Research suggests that oxepin can follow both the two single electron oxidation and further epoxidation metabolic pathways when exposed to enzymes CYP1A2 and CYP3A4 under multiple concentrations of enzyme with a fixed concentration of model oxepin substrate. Amides and lactams are common structural motifs found in a variety of natural products and construct the backbone of amino acid chains, proteins, and enzymes. Amides have 3 major resonance contributors. 4-Silatranones have been calculated previously to have the nitrogen lone pair delocalized like in normal amides vs. having a coordinate covalent bond with silicon as in silatranes, which is a bridged bicyclic amine dependent upon conformation. This research aims to synthesize strained lactams known as 4-silatranones and to help elucidate who wins the competition for nitrogen’s lone pair-the silicon via dative bond or delocalization into the amide carbonyl. Iron chelators have many biological applications including the treatment of iron overload disease, the suppression or promotion of reactive oxygen species production and even the ability to sense the iron status in the cell. Development of a chelator that can modulate and sense intracellular iron is the goal of this research. 8-hydroxyquinoline has been shown as a powerful chelating agent for iron in the past when three equivalents of 8-hydroxyquinoline have been tethered to a tripodal linker allowing for a hexadentate chelator to completely sequester iron. This portion of the project focuses on the synthesis of a tripodal linker with a carboxylic acid handle (Figure 4) to attach the chelator to lysine residue of a SS-peptide (synthesized by a research group member) that targets the mitochondria of a cell which contain labile iron pools

A study of certain trace metals in sea water using anodic stripping voltammetry

Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution January, 1970Anodic stripping voltammetry utilizing a thin film mercury composite graphite electrode has been evaluated and applied for the direct analysis of the metals, Zn, Cu, Pb, and Cd in sea water. The electrode was observed to follow theoretical behavior for thin film electrodes and the technique was found not to be adversely affected by dissolved organic material in sea water. Good precision (ca., 5%) was obtained in both coastal and open ocean waters at the in situ concentrations of Zn, Cu, Pb, and Cd. It was shown that this method is at present most suitable for measurements of Cu, Pb, and Cd in sea water. Evidence is given suggesting that Ni may interfere with the determination of Zn through formation of an intermetallic compound, and further studies are indicated to understand this phenomenon. The anodic stripping apparatus was adapted and used conveniently on shipboard. It was demonstrated that stripping analysis could be combined with a method for the destruction of dissolved organic matter (photo-oxidation with ultra-violet radiation), and with an addification procedure to obtain measurements of trace metal speciation in sea water. An argument for the existence of Cu-aspartic acid chelates in sea water has been described theoretically and demonstrated empirically; suggesting that a significant fraction of Cu and other trace metals may be expected to be organically sequestered in sea water. A study of coastal waters employing the total method (anodic stripping-photo-oxidation-acidification) indicated the presence of a significant group of organic ligands that complex Cu (ca., 60%). It was also shown that the waters subject to gross pollution contain about 30% of the total Cu in very stable organic complexes that release Cu only when the dissolved organic matter is destroyed, and not when the pH of this sea water is adjusted to 3. An open ocean trace metal study of a thermal-front zone in the western Sargasso Sea gave data for Cu, Zn, Pb, and Cd that compared favorably with other relevant investigations. Higher free metal concentrations were observed south of the front than to the north, providing further evidence that these fronts may mark a change between southern and northern conditions in the Sargasso Sea. Data obtained from shipboard analyses using the total analytical method indicates the presence of weak organic complexes with Cu and Pb in open ocean waters.This research has been supported for various periods by funds granted by the U.S. Office of Naval Research Contract 1841 (74), U.S. Atomic Energy Commission Contracts AT (30-1)-1919, and AT (30-1)-905, and a Graduate Fellowship provided by the Woods Hole Oceanographic Institution

Testing of GdCl3 Doping in Water Cherenkov Antineutrino Detectors

Improved neutron and neutrino detection using water Cherenkov detectors loaded with gadolinium has been proposed for potential application in both large and small volume detectors. In this thesis, work performed to determine the effect on transparency resulting from use of GdCl3 in stainless steel constructed water Cherenkov detectors is presented. In addition, results of an experiment performed using a small volume water Cherenkov de- tector are reported. This was the first use of gadolinium loaded water to detect reactor antineutrinos

Signs of blackness.

The life of an African American male homosexual artist, making his way in the theatre of America, is one of paradox. It is comprised of a litany of limited choices which also stay in flux. Yet in this void of choice, one must find a way to stay true to oneself, his racial heritage, and sexual/spiritual core. An artist of color, he must try to maintain this firm foundation while working as a commercial artist in the white supremacist, patriarchal, capitalistic, hetero-normative culture that is the American theatre. The signs of blackness that are intended, given, and received by my audiences vary greatly. In my sojourn at the University of Louisville, I have played many roles that have strengthened, broken, and confused archetypal black stereotypes. This thesis will explore and analyze my journey. Chapter 1 explains my start in acting, my birth as an artist, the mentors who inspired me and fostered the genesis of my artistic passion, the formation of my aesthetic sense as an artist, and my reasons for deciding to go to graduate school and further my academic exploration of acting. Chapter 2 includes an analysis of three roles I have played at the University of Louisville, examining them through the lens of rehearsal, production, and the signs intended and perceived through my performance. Chapter 3 describes my thesis role. A full examination of my process, the character analysis of the role, the rehearsal, and revelations found during the process. Chapter 4 discusses performance and the direction my thesis role has traveled. My journey as the character is explored there. Chapter 5 details what is next for me artistically and what I leave behind for future graduate students

Conversation analysis, practitioner based research, reflexivity and reflective practice: Some exploratory remarks.

During the course of this paper we intend to explore some possibilities that relate to ethnomethodology, conversation analysis, reflexive practice and practitioner based research. We intend to explore the way in which conversation analysis may facilitate some objectives and goals of reflexive practice and practitioner based research within professional practice. In order to fulfil this objective, this paper will discuss and describe the methodological approach of conversation analysis, explore the principles of reflexive practice and practitioner based research and consider the extent to which conversation analysis may be used as a means of fulfilling the aims of these inter-related projects within professional settings

Molecular Characterisation of Bacteriophage K Towards Applications for the Biocontrol of Pathogenic Staphylococci

End of project reportThe aim of this work was to characterise staphylococcal bacteriophage (a bacterial virus) and to assess their potential as therapeutic agents against pathogenic strains of Staphylococcus aureus, particularly mastitis-causing strains. The project included the use of two newly isolated phage CS1 and DW2, and an existing polyvalent phage. The new phage were isolated from the farmyard and characterised by electron microscopy and restriction analysis. Both phage were shown to belong to the Siphoviridae family and were lytic for representatives of all three clonal groups of Irish mastitis-associated staphylococci. A cocktail of three phage (CS1, DW2 and K) at 108 (plaque forming units) PFU/ml was infused into cows teats in animal trials. The lack of an increase in somatic cell counts in milks indicated strongly that the phage did not irritate the animal. In addition, the most potent phage used in this study, phage K, was further studied by genome sequencing, which revealed a linear DNA genome of 127,395 base pairs, which encodes 118 putative ORFs (open reading frames)

Is there a relationship between Water Potential and the Mechanical Strength of Salix lasiolepis?



Bioaccumulation and trophic transfer of methylmercury in Long Island Sound

Author Posting. © Springer, 2006. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Archives of Environmental Contamination and Toxicology 51 (2006): 416-424, doi:10.1007/s00244-005-0265-7.Humans are exposed to methylmercury (MeHg) principally by consumption of marine fish. The coastal zone supports the majority of marine fish production, and may therefore be an important source of MeHg to humans; however, little is known about the bioaccumulation or MeHg in near-shore marine ecosystems. We examined MeHg in microseston, zooplankton, a decapod crustacean and four representative species of finfish that differ in trophic status and/or prey selection in Long Island Sound (LIS), a large coastal embayment in the northeastern United States. MeHg biomagnifies in LIS; levels in microseston were 104.2 greater than those in water and 2.3-fold less than zooplankton. MeHg concentrations were related positively to fish length for each species, but often varied considerably among larger individuals. This may be due to differences in the past dietary MeHg exposure of these fish, some of which are migratory. Sedimentary production and mobilization can account for most of the MeHg in microseston of LIS, and by extension, other near-shore locations. Hence, much of the MeHg in higher trophic levels of coastal marine ecosystems, including fishes destined for human consumption, may be attributed to net sedimentary production and dietary bioaccumulation.This study was supported by a STAR grant (R827635) and graduate student fellowship (U91591801) from the U.S. EPA, and the Postdoctoral Scholar Program at the Woods Hole Oceanographic Institution, with funding provided by the Doherty Foundation