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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
401

Gender Representation in the Media : A Critical Analysis of the Construction of Female Sexuality in Men's Pornographic and Non-Pornographic Magazines

Tognela, Jennifer January 2011 (has links)
This thesis applies the radical feminist perspective set out by MacKinnon (1993) and Dworkin (1995), to analyze the construction of female sexuality within popular Canadian men’s pornographic magazines and non-pornographic magazines. A mixed methods approach was used to analyze the images and text within the feature articles of the selected magazines. Results revealed that women continue to be constructed as sexual objects within both categories of magazines, but the earlier link identified by MacKinnon and Dworkin between violence and sexuality was on longer apparent. Instead, women were a sexual puzzle that the magazines attempted to unpack. Rather than a strict dichotomy between pornographic and non-pornographic magazines, a continuum of grey emerged whereby the level of explicitness between the two magazines increased as the continuum progressed from left to right, thereby demonstrating the pornographication of mainstream media, as per McNair (2002).
402

Development of Radical Cascade via Gold(I) Photocatalysis and Application towards One-Pot Bromination/Carbocyclization

Lanoix, Stéphanie January 2015 (has links)
Radical chemistry is a crucial tool to organic chemists. Recent trends in the field have been directed towards the development of photocatalysts capable of generating a radical through a renewable source like sunlight using a single electron transfer mechanism. The use of Au2dppm2Cl2, having a stronger reducing potential, allows an expansion of the reactivity to those achieved by iridium and ruthenium catalysts.1 The focus of this thesis is axed on the development of Au2dppm2Cl2 as an efficient photoredox catalyst for a tandem one-pot catalysis and its application in a dual catalytic system. The use of Au2dppm2Cl2 in a dual catalysis for the synthesis of β-amino acids was undertaken. The problems encountered over the course of the investigation showed an insufficient oxidation potential of the photoredox catalyst in addition to the facile homolytic cleavage of the C-halogen bond under UV light. However, this shows great promise for the achievement of beta amino acids using solely organocatalysis. The development of a tandem one-pot radical cyclization for the synthesis of fused- carbocycles, which are frequently encountered scaffolds in diterpenoid natural products, is reported. The initial experiments were conducted on a model substrate, enabling the verification of the proposed hypothesis. The success of this methodology was then applied to various substrates affording the desired fused 5 membered rings in good yields. These reactions show tremendous potential in the field of total synthesis for the rapid access of complex molecular structures. (1) Revol, G.; McCallum, T.; Morin, M.; Gagosz, F.; Barriault, L. Angew. Chem. Int. Ed. 2013, 52, 13342.
403

Mathematical Modeling of Immuno-radioprotector Delivery System Using a Monoclonal Antibody

Alhassani, Maha January 2015 (has links)
Amifostine (WR-2721, delivered as Ethyol) is a radioprotector agent that reduces the likelihood of early and/or late biological effects by eliminating free radical particles during ionizing radiation fraction (radiotherapy). It activates in under normal tissues conditions to reduce mutation and fraction in DNA. Among 4000 prodrug compounds, amifostine is the only agent has been approved from the US Food and Drug Administration in clinical purposes. The main effective mechanisms of amifostine are based on scavenging for free radical, improving for DNA repair step and indication of cellular hypoxia. In the same time, this drug is not widely used around the world for different reasons mainly its high cost and toxicity level (lethal dose). Conjugating a monoclonal antibody with amifostine by a suitable linker is a process of Antibody Drug Conjugate producing immuno-radioprotector molecule hypothesis. Administrated molecule is an approach of targeted delivery therapy that increases the dosage uptake into particular area of treatment to minimize the dose distribution in non-targeted area in the body. In the present work, we proposed a three-compartment system model to simulate the two-pore theory pathway of an immuno-radioprotector molecule when it is crossing the physiological barriers. The model investigated its distribution and elimination in porous media (with both large and small pores) within a pharmacokinetics compartmented model approach.
404

Investigating the Interactions between Free Radicals and Supported Noble Metal Nanoparticles in Oxidation Reactions

Crites, Charles-Oneil January 2015 (has links)
This thesis studies the interaction between free radical species and supported noble metal nanoparticles (silver and gold) in the context of oxidation reactions. The peroxidation of cumene is the first reaction to be discussed and the difference in peroxidation product distribution using silver nanoparticles (AgNP) versus gold nanoparticles (AuNP) is examined. Specifically, cumyl alcohol is obtained as the major product obtained when using supported AuNP, whereas cumene hydroperoxide is favoured for AgNP. Such variations in product distribution are partially explained by the differences in the nanoparticle Fenton activity, where the TiO2 support was proposed to enhance such activity due to possible electron shuttling capabilities with the nanoparticle surface. Use of hydrotalcite as a support was found to minimize this characteristic, due to its insulator properties. The stability of hydroperoxide was tested in the presence of various others supports (activated carbon, Al2O3, ZnO, SiO2 and clays) with little success, with hydroperoxide exhibiting stability in the presence of HT. Using an oxygen uptake apparatus, the interaction of the cumyl peroxyl radical with the AuNP surface was demonstrated. Furthermore, this interaction promotes decomposition leading to the corresponding alkoxyl radical and subsequent hydrogen abstraction to form the observed cumyl alcohol product. The radical interaction with supported nanoparticles, and its reversibility appear different for gold and silver and accounts for a large part of the product distribution differences observed between AuNP and AgNP, as illustrated below. The peroxidation of ethylbenzene and propylbenzene was studied and revealed the participation of a reactive surface oxygen species due to the decomposition of peroxyl radicals on the nanoparticle surface. The reactive oxygen species was found to be transient in nature in the case of AuNP . Furthermore, this surface species was found to be an important participant in hydrogen abstraction leading to peroxide product formation. Finally, supported nanoparticle catalyzed tetralin peroxidation was investigated to determine the influence of temperature on the peroxidation product distribution and how changes in the reaction temperature can effect the radical-nanoparticle surface interactions.
405

Synthesis, Kinetics and Mechanisms of Designer and Natural Product Antioxidants: From Solution to Cells

Li, Bo January 2016 (has links)
Lipid peroxidation has been implicated in the onset and progression of many degenerative diseases, including cardiovascular disease, Alzheimer’s disease and cancer. Accordingly, for more than 50 years, considerable effort has been devoted to the design of synthetic compounds or the discovery of natural products that can slow lipid peroxidation. Despite the enormous investments made to date, no clear antioxidant strategies have emerged for the treatment and/or prevention of degenerative disease. We argue that this is because of a lack of fundamental understanding of the chemical reactivity of these compounds in relevant contexts. Herein, we describe studies of our optimized synthetic radical-trapping antioxidant (RTA) – the tetrahydronaphthyridinols (THNs). We first present the synthesis of a series of THN analogs of α-tocopherol (Nature’s premier lipid-soluble radical-trapping antioxidant) with varying sidechain substitution and then demonstrate how systematic changes in the lipophilicity of these potent antioxidants impact their peroxyl radical-trapping activities in lipid bilayers and mammalian cell culture. Their regenerability by water-soluble reductants in lipid bilayers, binding to human tocopherol transport protein (hTTP), and cytotoxicity were also evaluated to provide insight on whether this type of antioxidant can be potentially pushed toward animal studies. We also describe analogous studies of natural products such as the garlic-derived thiosulfinate allicin and the grape-derived polyphenol resveratrol. These compounds have attracted significant attention in the past 20 years due to their purported health benefits, which are often ascribed to their purported radical-trapping activities. To date, systematic studies on their radical-trapping activities in solution, lipid bilayers and mammalian cells have been lacking. We have determined that allicin and petivericin, while effective RTAs in solution, are not so in lipid bilayers. Moreover, the compounds are not antioxidants in cell culture, but instead kill the cells. Similarly, resveratrol and its dimers pallidol and quadrangularin A, are found to be inefficient RTAs in lipid bilayers. Our studies to date rather suggest that they autoxidize readily to produce hydrogen peroxide, which may induce expression of phase 2 antioxidant enzymes, affording cytoprotection. Our insights underscore the need for systematic studies of antioxidant activity in multiple contexts.
406

School change and leadership : an insider perspective of how school change can be achieved within a centralised education system

Constantinou, Elena January 2014 (has links)
The study reported in this thesis investigates how change was managed within one school with a view to drawing out implications for the relationship between school improvement and leadership. Significantly, it examines the challenge of bringing about school improvement in a highly centralised education system, using the example of Cyprus.
407

The Investigation of Photocatalysts and Iron Based Materials in the Oxidation and the Adsorption of Toxic Organic and Chromium Materials

Jiang, Wenjun 13 November 2013 (has links)
The presences of heavy metals, organic contaminants and natural toxins in natural water bodies pose a serious threat to the environment and the health of living organisms. Therefore, there is a critical need to identify sustainable and environmentally friendly water treatment processes. In this dissertation, I focus on the fundamental studies of advanced oxidation processes and magnetic nano-materials as promising new technologies for water treatments. Advanced oxidation processes employ reactive oxygen species (ROS) which can lead to the mineralization of a number of pollutants and toxins. The rates of formation, steady-state concentrations, and kinetic parameters of hydroxyl radical and singlet oxygen produced by various TiO2 photocatalysts under UV or visible irradiations were measured using selective chemical probes. Hydroxyl radical is the dominant ROS, and its generation is dependent on experimental conditions. The optimal condition for generation of hydroxyl radical by of TiO2 coated glass microspheres is studied by response surface methodology, and the optimal conditions are applied for the degradation of dimethyl phthalate. Singlet oxygen (1O2) also plays an important role for advanced processes, so the degradation of microcystin-LR by rose bengal, an 1O2 sensitizer was studied. The measured bimolecular reaction rate constant between MC-LR and 1O2 is ~ 106 M-1 s-1 based on competition kinetics with furfuryl alcohol. The typical adsorbent needs separation after the treatment, while magnetic iron oxides can be easily removed by a magnetic field. Maghemite and humic acid coated magnetite (HA-Fe3O4) were synthesized, characterized and applied for chromium(VI) removal. The adsorption of chromium(VI) by maghemite and HA-Fe3O4 follow a pseudo-second-order kinetic process. The adsorption of chromium(VI) by maghemite is accurately modeled using adsorption isotherms, and solution pH and presence of humic acid influence adsorption. Humic acid coated magnetite can adsorb and reduce chromium(VI) to non-toxic chromium (III), and the reaction is not highly dependent on solution pH. The functional groups associated with humic acid act as ligands lead to the Cr(III) complex via a coupled reduction-complexation mechanism. Extended X-ray absorption fine structure spectroscopy demonstrates the Cr(III) in the Cr-loaded HA-Fe3O4 materials has six neighboring oxygen atoms in an octahedral geometry with average bond lengths of 1.98 Å.
408

GENDER-CRITICAL/ GENDERLESS? A CRITICAL DISCOURSE ANALYSIS OF TRANS-EXCLUSIONARY RADICAL FEMINISM (TERF) IN FEMINIST CURRENT

Vajjala, Emily 01 May 2020 (has links)
Feminist Current is a multi-author Canadian self-proclaimed feminist website which frequently publishes trans-exclusionary radical feminist (TERF) discourse via blogs, podcasts, and global news. This project is a critical discourse analysis of the ways in which Feminist Current communicatively constructs and deconstructs transgender identity in problematic and exclusionary ways. In this study, I consider significant definitions given through Feminist Current, entertain the question of whether TERF is a slur, and discuss the major themes. Based on twenty-three sampled essays published on Feminist Current, I find that Feminist Current authors use five major themes in their discourse: violence against women, strategic censorship, antimanipulation and pro-bodily autonomy, performances of humor and naivete, and calls for solidarity. This discourse functions to separate transwomen from women’s spaces and position transwomen as illegitimate and aggressive, while simultaneously repositioning radical feminism as a superior ideological framing.
409

Development of All-Organic Magnetic Mixed Micelles Aiming at Biomedical Application / 生物医療応用を目指した純有機磁性混合ミセルの開発

Nagura, Kota 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(人間・環境学) / 甲第21873号 / 人博第902号 / 新制||人||215(附属図書館) / 2018||人博||902(吉田南総合図書館) / 京都大学大学院人間・環境学研究科相関環境学専攻 / (主査)教授 小松 直樹, 教授 加藤 立久, 准教授 廣戸 聡 / 学位規則第4条第1項該当 / Doctor of Human and Environmental Studies / Kyoto University / DFAM
410

Development of Transformation Reactions with Alkylsilyl Peroxidesas Alkyl Radical Precursors under Cu Catalysis / 銅触媒存在下アルキルシリルペルオキシドをアルキルラジカル源として用いる分子変換反応の開発

Sakurai, Shunya 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(理学) / 甲第23029号 / 理博第4706号 / 新制||理||1675(附属図書館) / 京都大学大学院理学研究科化学専攻 / (主査)准教授 加納 太一, 教授 依光 英樹, 教授 時任 宣博 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

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