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This body of work endeavours to interrogate mainstream media and popular culture [mis]representations of racialized persons, in addition to the negative impact such imageries have on identity formation processes - principally amongst populations of young men and women of African descent. While this work focuses on North American contexts, this examination is applicable to all peoples in the African Diaspora. I intend to uncover the learning possibilities for racialized youth, by introducing an educational model that prepares students to critique various forms of media, as well as teaching and encouraging them to create their own realities through the use of a critical form of media education in multiple level classrooms, starting with those in the Toronto District School Board. The ultimate goal of this project is to propel racialized students to move away from the [mis]educative effects of the media, toward beginning to define themselves on their own terms.

The first objective of this thesis was to assess the feasibility of designing a “smart” degradable polymer that can release anti-inflammatory drugs in response to inflammatory-related enzymes. The drug polymer was synthesized using diisocyanates, poly(caprolactone)diols, and oxaceprol (OC) biomonomers. Biodegradation studies demonstrated that the trimethylhexamethylene diisocyanate-based drug polymer responded to an inflammatory enzyme to release more OC, while a 1, 12-diisocyanatododecane analog demonstrated minimal drug release. The drug delivery response was believed to be a direct function of the molecular structure and distribution of the hard segment. The second objective of this thesis was to elucidate the anti-inflammatory mechanisms of OC by investigating its effects on cytokine-induced monocytic-cells adhesion in human umbilical vein endothelial cells (HUVECs) in vitro. Results showed that OC had no direct effect on the monocyte-endothelium adhesion, suggesting that OC may mediate inflammation by mechanisms other than those suggested by the literature.

Although nanocrystalline silver is used commercially to treat burns and wounds, the mechanisms of action (MOA) for its activity are not clear. The purposes of this work were to determine if nanocrystalline silver has anti-inflammatory activity, determine physicochemical properties critical for its MOA, and develop nanocrystalline silver-derived solutions for use in the treatment of lung diseases, including ARDS and pneumonia. In a porcine contact dermatitis model, nanocrystalline silver had anti-inflammatory activity independent of antimicrobial activity, with increased apoptosis induction in inflammatory cells, but not keratinocytes; decreased expression of TNF-, TGF-, IL-8, and MMPs; and increased expression of IL-4, EGF, KGF, and KGF-2. Treatment with AgNO3 (Ag+) increased inflammation, and caused apoptosis induction in keratinocytes. Thus, nanocrystalline silver releases additional species, perhaps Ag^(0)-containing clusters, resulting in anti-inflammatory activity. SIMS analysis showed significant deposition of Ag-clusters after nanocrystalline silver, but not AgNO3, treatment. Nanocrystalline silver had a systemic effect, despite SIMS analysis showing minimal skin penetration by silver, suggesting that nanocrystalline silver interacts with cells near tissue surfaces that release signals altering the inflammatory cascade. Relative to various Ag+-releasing dressings, nanocrystalline silver had significantly enhanced antimicrobial activity, Ag+-resistant bacteria kill, and was not prone to development of resistant bacteria, indicating that nanocrystalline silver releases antimicrobial species additional to Ag+, and has multiple bactericidal MOA. Single silver nanocrystals are inactive, and heat treatment of nanocrystalline silver resulting in crystallites over ~30 nm caused loss of antimicrobial activity, soluble silver, silver oxide, and oxygen. This indicates a poly-nanocrystalline silver structure is necessary for optimal antimicrobial activity, as is having silver oxide to pin the nanostructure, preventing its growth. While oxygen is necessary during sputtering to produce silver oxide, too much oxygen reduces antimicrobial activity, as silver oxide is predominantly deposited. Sufficient total silver, modifiable with current and time, is also important for activity. Nanocrystalline silver-derived solution properties vary significantly with dissolution conditions. Solutions generated at pH 4-6 have stronger antimicrobial activity, and solutions generated at pH 9 have stronger anti-inflammatory activity. Overall, nanocrystalline silver-derived solutions have biological properties similar to nanocrystalline silver, indicating that they may be useful in a variety of medical applications.

The overall emphasis of this doctoral dissertation is on the design, synthesis, detailed characterization and application of amphiphilic hyperbranched fluoropolymers (HBFPs) crosslinked with poly(ethylene glycols) (PEGs) in complex polymer coatings as anti-biofouling surfaces. This dissertation bridges synthetic polymer chemistry, materials science and biology to produce functional coatings capable of fouling prevention, demonstrating thermo-controlled healing and acting as a benchmark surface to understand component:property relationships prior to increasing formulation complexities. A two-dimensional array of HBFP-PEG coatings was produced by the co-deposition of uniquely composed HBFPs with varying weight percentages of PEG. Bulk and surface properties were evaluated and assigned to formulation trends. Based on these findings, the most viable candidates were replicated and their fouling responses were assessed against three marine fouling organisms. An active mode of biofouling resistance was covalently grafted onto the surface of HBFP-PEG. The presentation of the settlement-deterrent molecule noradrenaline (NA) works in tandem with the highly-complex surface, to act as a dual-mode, anti-biofouling coating NA-HBFP-PEG. Secondary ion mass spectrometry (SIMS) was employed to quantify the extent of NA substitution. Biological assays against oyster hemocytes confirmed the activity of the grafted NA and cyprid settlement assays supported that the overall anti-biofouling ability of NA-HBFP-PEG was increased by 75%. Thermally-reversible crosslinks were installed as healable units throughout the framework of the networks, with the goal of generating coatings that could possess a greater resistance to mechanical failure. Small molecule and linear polymer models were probed by nuclear magnetic resonance (NMR) spectroscopy and gel permeation chromatography (GPC) to demonstrate the controlled reversibility of the crosslinks. Optical microscopy was employed to visualize surface scratch healing and fluorescence microscopy was used to identify the adsorption behavior of fluorescently-labeled proteins. A benchmark, anti-biofouling surface was generated through thiol-ene crosslinking of a linear fluoropolymer with pendant alkenes (LFPene) with pentaerythritol tetrakis(3-mercaptopropionate) (PETMP). Core constituents were evaluated spectroscopically and surfaces of LFPene-PETMP, along with two model surfaces that largely expressed a single component, were analyzed to understand how individual elements and blending contributed to the physical, mechanical and anti-biofouling properties to generate a performance baseline to compare against future generations.

Thesis (PhDPharmacy)--University of South Australia, 2003.

Bibliography: leaves 159-164. / iv, 158 leaves ; 30cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis examines routes for the asymmetric synthesis of three members of the nonsteroidal anti-inflammatory class of drugs (NSAIDs) The aryl propanoic acid ibuprofen is synthesized in 96% e.e. Control of stereochemistry is achieved by use of the Sharpless epoxidation reaction, followed by reduction of the product epoxide by complex hydride with assistance by titanium tetraisopropoxide acting as a Lewis acid. The final step is the coupling of an optically active carboxylic acid intermediate with the iso-butyl side chain to give (S)-ibuprofen. / Thesis (Ph.D.)--University of Adelaide, Dept. of Organic Chemistry, 1997?

xiv, 165, xxix leaves : graphs, tables ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Microbiology, 1975

Doctor of Philosophy(PhD) / The present study deals with the synthesis, characterization, determination of anticancer activity of three mononuclear trans-planaraminepalladium(II) complexes code named TH5, TH6 and TH7 and three trinuclear complexes code named TH1, TH8 and TH14. The activity of the compounds against human cancer cell lines: A2780, A2780cisR and A2780ZD0473R, cell uptake, DNA-binding and nature of interaction with pBR322 plasmid DNA have been determined. Whereas cisplatin binds with DNA forming mainly intrastrand GG adduct that causes local bending of a DNA strand, TH5, TH6, TH7, TH1 and TH8 bind with DNA forming mainly interstrand GG adducts that causes more of a global change in DNA conformation. Although TH5, TH6 and TH7 each have two substituted pyridine ligands in a trans-geometry (3-hydroxypyridine in TH5, 2-hydroxypyridine in TH6 and 4-hydroxypyridine in TH7), the compounds differ in their activity against ovarian cancer cell lines, indicating that non-covalent interactions involving the hydroxyl group may be playing a significant role in activity of the compounds. Among trinuclear complexes TH1 is found to be significantly more active than cisplatin. It is actually twice as active as cisplatin against the parent cell line A2780, thirteen times as active as cisplatin against the cisplatin-resistant cell line A2780cisR and 11.5 times as active as cisplatin against the cell line A2780ZD0473R. Whereas the resistance factor for cisplatin as applied to the cell lines A2780 and A2780cisR cell lines is 12.9 that for TH1 is 1.98. The results suggest that TH1 has been able to significantly overcome resistance operating in A2780cisR cell line. The compound is soluble in water so that it may be taken orally. Provided it has favourable toxicity profile, TH1 has the potential to be developed into a highly active anticancer drug with a wider spectrum of activity than cisplatin. Although platinum drugs use a shot-gun approach to kill cancerous cells, widespread use in the clinic and increasing volume of their sale indicate that even in the genomic age, there is still need for shot-gun drugs in the clinic.

The overall aims of this thesis were to conduct a broad survey of possible organic corrosion inhibitors in near-neutral chloride solutions and to elucidate the mechanisms of such action. Altogether, 130 organic compounds were studied as possible corrosion inhibitors for pure iron, mild steel, copper and aluminium in aerated near-neutral (pH = 8.4) solutions containing 500 ppm NaCl and 100 ppm NaHCO,, conditions often encountered in water-based automotive engine coolants. Inhibitor behaviour was investigated using steady-state electrochemical techniques including polarisation curves, Stern-Geary and corrosion potential (Em,) measurements. The organic compounds examined were found to be highly specific in their inhibitive action toward the metals studied. Typical examples of highly effective corrosion inhibitors were: sebacate and octanoate for pure iron; oleate and sebacate for mild steel; benzotriazole and 2-mercaptobenzothiazole for copper; and laurate and oleate for aluminium. E, was found to provide a rapid and convenient screening test for evaluating the inhibitor performance of organic compounds toward pure iron, mild steel and aluminium but was less useful for copper. Good organic inhibitors were found to act as anodic inhibitors toward pure iron and mild steel but as anodic or mixed-type inhibitors toward copper. For aluminium, the majority of the compounds studied were found to act as anodic inhibitors. However,However, it was also found that only pit initiation was inhibited, i.e. existing pits were not prevented from developing. Optical microscopy of pitted aluminium surfaces indicated their nature varied considerably with inhibition efficiency. The role of complex formation in organic corrosion inhibitors was found to vary with the metal. Complexation of either iron(I1) or iron(II1) ions was found to have an insignificant effect on mild steel. The corrosion rate of copper was found to increase with the copper(LI) complex stability, thus indicating complex formation to be the rate-determining step. For aluminium, the observed effects were found to depend on complex stability. For weak to moderate complexants, inhibitor efficiency (measured as E,,) increased with increasing complexation. However, very strong complexing agents were sufficiently stable to dissolve the aluminium oxide surface, leading to poor inhibition. Aluminium pit morphology was found, using scanning electron microscopy, to change from hemispherical in the uninhibited solution to irregular in the presence of complexing inhibitors. No simple relationships between inhibitor efficiency and molecular structure were found. However, carbon chain length, the nature of functional group(s) and their location in the molecule were found to be important but varied according to the metal. The inhibiting ability of sebacate (a straight chain C, dicarboxylate) was found not to be compromised by water movement (stirring) or pre-existing corrosion product layers. Immersion tests showed that passive film formation on mild steel in sebacate solution involved two stages and was complete only after -100 h immersion. The ion selective properties of several iron(II1) carboxylates and hydrated iron(II1) oxide films were studied by membrane potential measurements in neutral sodium chloride solutions. Some specimens were also studied by Mossbauer spectroscopy. These results show that dicarboxylates are good inhibitors toward mild steel because they form impermeable films. Poor inhibitor performance is associated with the anion selectivity of the film which in turn appears to be related to the film purity. A model is suggested for the inhibition mechanism of mild steel corrosion by dicarboxylates in aerated near-neutral chloride solutions.