Thesis (Ph.D. (Zoology))--North-West University, Potchefstroom Campus, 2008.

Since its characterization, the definitive shortcoming of the bacterial luciferase (lux) bioluminescent reporter system has been its inability to express at a functional level in the eukaryotic cellular background. While recent developments have allowed for lux function in the lower eukaryote Saccharomyces cerevisiae, they have not provided for autonomous function in higher eukaryotes capable of serving as human biomedical proxies. Here it is reported for the first time that, through a process of poly-bicistronic expression of human codon-optimized lux genes, it is possible to autonomously produce a bioluminescent signal directly from mammalian cells. The low background of the bioluminescent signal, along with its characteristic lack of substrate amendment required for bioluminescent production, makes a mammalian-based lux reporter system ideal for real-time monitoring of cell culture or murine model systems. The delectability of a lux-based system provides for a functionally equivalent process to monitoring firefly luciferase-expressing cells under cell culture or subcutaneous imaging conditions without the well-documented uncertainties stemming from additional substrate introduction. However, the relatively blue-shifted emission wavelength of the lux reporter system, along with its low quantum yield, has been shown to reduce its effectiveness for use during deep tissue imaging of animal subjects. Despite these disadvantages, it has been demonstrated that a human cell line expressing the human codon-optimized lux genes can function as a biosensor for determination of human bioavailability of toxic compounds and that, by regulating the production of the luxC and luxE genes, the lux system can be employed as the first mammalian, real-time, fully autonomous bioreporter. These cell lines provide unique and efficient models for the detection and monitoring of human-relevant compounds of interest. The limiting reagent for bioluminescent production in the mammalian cellular background has been determined to be the cytosolic availability of the FMNH2 co-substrate and, in light of this evidence, directions for future optimization have been characterized and evaluated in respect to their ability to increase bioluminescent yield under these conditions.

Le milieu de la bande dessinée au Québec s'est enrichi depuis quelques années de nouvelles structures éditoriales qui ont favorisé l'éclosion de nombreux talents, particulièrement à l'intérieur du champ autobiographique. Le but de ce mémoire est de mettre en lumière certaines de ces voix singulières : Jimmy Beaulieu, Michel Rabagliati, Luc Giard, Line Gamache, Geneviève Castrée et Julie Doucet. Le propre de l'autobiographie en bande dessinée étant de représenter graphiquement le personnage, je m'attarderai ici à la manière dont le «je» est figuré. Cet avatar, amalgame de l'auteur et de son style, peut adopter différentes postures, l'une, par exemple, exposant l'introspection ou une autre, au contraire, provoquant l'identification du lecteur. La focalisation les influence fortement. De plus, les différentes catégories du champ autobiographique se déclinent par un contrat de lecture, proposant une stratégie d'ambiguïté ou un pacte référentiel, et par la structure narrative ou spéculative de l'œuvre. Elles ont une forme plus moderne selon leur capacité à se remettre en question. Mon hypothèse est celle de l'existence d'un lien entre le type de discours (autobiographie, récit autobiographique, roman autobiographique et auto-essai) et les perspectives employées. Pour la vérifier, j'ai formé, au préalable, trois couples en réunissant les œuvres qui présentent l'auteur avec certaines affinités. Cela a permis la comparaison et l'exploration des différents modes d'expression de mon objet d'étude. Le point de vue le plus usuel est sans conteste la perspective externe qui institue le «je» en personnage. Ses effets varient cependant selon la catégorie utilisée. Le point de vue interne est plutôt minoritaire et renforce un «je» déjà au plus près de l'auteur. La focalisation zéro sert, dans les exemples étudiés, à transmettre les perceptions et à donner accès directement aux pensées. Enfin, le point de vue expressif exhibe le bouleversement du créateur jusque dans son trait. Ainsi, ceux qui exposent leur intériorité sont aussi ceux qui utilisent des narrations qui se remettent en question: Jimmy Beaulieu, Luc Giard et Geneviève Castrée. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : bande dessinée, points de vue, autobiographie

La pensée politique se heurte aujourd'hui à l’impossibilité de définir la communauté politique une fois les catégories traditionnelles (Nation, Peuple, Classe) mises en déroute. À l'heure de la critique de toutes les catégories totalisantes, de toutes les essences, la tâche de penser le commun paraît ardue. Pourtant, trois auteurs de philosophie politique, Giorgio Agamben, Jean-Luc Nancy et Jacques Rancière, ont tenté, dans leurs œuvres respectives, de relever le défi. Ce mémoire passe en revue leurs propositions pour une communauté désubstantialisée, ne s'assemblant plus autour d'une particularité exclusive mais ne sombrant pas non plus dans l'universalisme abstrait. Il présente les prémisses principales sur lesquelles s'appuie cette vision de la communauté : une politique sans archè, la fin de toute téléologie et l'appropriation de l'impropriété. La dernière partie du mémoire présente la proposition de recherche qui stipule que c'est en réactivant le thème de l'exigence communiste que ces trois auteurs peuvent énoncer la communauté politique comme un partage extatique, évitant le piège du libéralisme mais aussi du communautarisme. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : communauté, Jacques Rancière, Jean-Luc Nancy, Giorgio Agamben, extatique, anarchie, Bataille, désœuvrement, singularité, impropriété, commun, exigence communiste.

Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains vii, 179 p. Includes abstract and vita. Advisor: Eugene Holland, Dept. of French and Italian. Includes bibliographical references (p. 165-179).

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal

Persistent organic pollutants (POPs) are a threat to the environment and human health because they are ubiquitous, resistant to degradation, can bio-accumulate in organisms and bio-magnify in food chains. They have a detrimental effect on the reproductive, nervous and immunity systems of vertebrates. An international treaty, the Stockholm Convention on POPs, came into force in 2004 and aims to limit and eventually prohibit any use and unintentional production of POPs. South Africa ratified the Convention in 2002. Those compounds currently listed by the Stockholm Convention as POPs include chlorinated pesticides such as dichlorodiphenyltrichlorethane (DDT), chlordane and dieldrin, and industry-related compounds such as polychlorinated biphenyls (PCBs) and hexachlorobenzene. Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are also regarded as POPs but - together with some PCBs - they are the unintentional result of anthropogenic activity. This study focussed on the PCDDs, PCDFs and dioxin-like PCBs in the aquatic environment of South Africa particularly because the water resources in this country are under pressure. Despite the fact that South Africa has the sources of these compounds, little is known about the levels of these three groups of compounds. The concentration of twelve dioxin-like PCBs, seven PCDDs and ten PCDFs were determined for 22 sites selected on the grounds of their proximity to possible pollution sources. Analytical determinations included gas chromatography/mass spectrometry and a cell-based bio-assay, the H4IIE-/17C reporter gene assay. Possible sources of the observed pollution were inferred using the following statistical investigative methods: principal component and hierarchical cluster analysis. Seven of the sites had levels higher than the threshold effect concentration of Canada's sediment quality guidelines of 0.85 ngTEQ kg'1 (Toxic Equivalency Quotient). The other sites had lower levels. The highest concentration, 17.8 ng TEQ kg"1, was measured at a site in the southern Gauteng Province. Most of the PCDD/F pollution seemed to have come from combustion sources related to human activity, rather than industrial combustion. Most of the dioxin-like PCB pollution seemed to have been from commercial PCB preparations. Future research would require better characterisation of the sources in order to reduce the formation of these compounds, but also to better understand the exposure and risk scenarios, if humans are to be in close contact with these sources. / Thesis (Ph.D. (Zoology))--North-West University, Potchefstroom Campus, 2008.

Water resources in South Africa are scarce, and should therefore be protected against pollutants, also from persistent organic pollutants (POPs). POPs are a global concern due to their ubiquitous presence, persistence and toxicity. This is emphasised by the Stockholm Convention on POPs, which aims at reducing and ultimately eliminating them. South Africa signed and ratified the treaty, and it became international law on 17 May 2004, but there is still a lack of information regarding POPs in South Africa. This study focussed on establishing the levels of POPs and other organic pollutants, which included various organochlorine pesticides (OCPs), polycyclic aromatic hydrocarbons (PAHs), dioxin-like compounds (DLCs), non-dioxin-like polychlorinated biphenyls (PCBs) and polybrominated diphenyl ether (PBDE). Sampling regions included the industrial cities – Cape Town, Richards Bay, Durban and Bloemfontein, and low-income, high density residential areas surrounding a wetland in Soweto/Lenasia and Botshabelo. Additionally, rivers flowing into neighbouring countries, rivers in the vicinity of paper and pulp producers and high altitude rivers were included. Sediment samples were firstly screened for the presence of DLCs by the H4IIE-luc bio-assay, whereafter sites eliciting quantifiable responses were selected for further chemical analysis by high resolution gas chromatography-high resolution mass spectrometry (HRGC/HRMS). Of the 96 sites, only 23 had quantifiable levels of DLCs. These sites were mainly of industrial, semi-industrial or low-income residential nature. PAHs were the predominant class of compounds at most of the sites, while OCPs and PCBs were present in moderate concentrations and PBDEs in minor concentrations. The concentration of pollutants measured in South African soils and sediments were intermediate when compared to the levels measured in some European, Asian and Scandinavian countries, with the exception of a few sites where exceptionally high levels of compounds were measured. The carbon content normalized concentrations of certain compounds at some of the sites exceeded the Canadian sediment quality guidelines. The estimated cancer risk associated with dermal absorption of OCPs measured in this study was negligible when compared to the background cancer risk expected for South Africans due to life style factors. However, it was estimated that dermal exposure to PCBs, DLCs and PAHs may lead to severe increases in cancer cases, and may seriously impact on human health. / Thesis (Ph.D. (Environmental Science))--North-West University, Potchefstroom Campus, 2011.

Water resources in South Africa are scarce, and should therefore be protected against pollutants, also from persistent organic pollutants (POPs). POPs are a global concern due to their ubiquitous presence, persistence and toxicity. This is emphasised by the Stockholm Convention on POPs, which aims at reducing and ultimately eliminating them. South Africa signed and ratified the treaty, and it became international law on 17 May 2004, but there is still a lack of information regarding POPs in South Africa. This study focussed on establishing the levels of POPs and other organic pollutants, which included various organochlorine pesticides (OCPs), polycyclic aromatic hydrocarbons (PAHs), dioxin-like compounds (DLCs), non-dioxin-like polychlorinated biphenyls (PCBs) and polybrominated diphenyl ether (PBDE). Sampling regions included the industrial cities – Cape Town, Richards Bay, Durban and Bloemfontein, and low-income, high density residential areas surrounding a wetland in Soweto/Lenasia and Botshabelo. Additionally, rivers flowing into neighbouring countries, rivers in the vicinity of paper and pulp producers and high altitude rivers were included. Sediment samples were firstly screened for the presence of DLCs by the H4IIE-luc bio-assay, whereafter sites eliciting quantifiable responses were selected for further chemical analysis by high resolution gas chromatography-high resolution mass spectrometry (HRGC/HRMS). Of the 96 sites, only 23 had quantifiable levels of DLCs. These sites were mainly of industrial, semi-industrial or low-income residential nature. PAHs were the predominant class of compounds at most of the sites, while OCPs and PCBs were present in moderate concentrations and PBDEs in minor concentrations. The concentration of pollutants measured in South African soils and sediments were intermediate when compared to the levels measured in some European, Asian and Scandinavian countries, with the exception of a few sites where exceptionally high levels of compounds were measured. The carbon content normalized concentrations of certain compounds at some of the sites exceeded the Canadian sediment quality guidelines. The estimated cancer risk associated with dermal absorption of OCPs measured in this study was negligible when compared to the background cancer risk expected for South Africans due to life style factors. However, it was estimated that dermal exposure to PCBs, DLCs and PAHs may lead to severe increases in cancer cases, and may seriously impact on human health. / Thesis (Ph.D. (Environmental Science))--North-West University, Potchefstroom Campus, 2011.

This thesis brings the philosophies of Jean-Luc Nancy, Slavoj Zizek and Bruno Latour into conversation around the cynosure of ecological rhetoric. It argues for a renewed contemplation of political ecology, one that relinquishes the concept of Nature in favour of the overtly politicized notion of a world in common. By tracing, for the first time, the intersections between these three thinkers’ respective philosophies of nature, this thesis strives to articulate a philosophical framework that can live up to the ecological challenges of the contemporary Anthropocene. / Graduate / 0422 / 0401 / 0298