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In this thesis, some issues about the human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) have been addressed by concentrating on the stochastic modelling of the dynamics of the viruses. The aim of this thesis is to determine parameters such as the mean number of free HIV, infectious free HIV and non-infectious free HIV which are essential in determining incubation period of the virus, the disease progression of an infected individual and the efficacy of the treatment used. This thesis comprises of six chapters. The first two chapters are introductory to the viruses and reasons why HIV-1 is given priority over HIV-2 are given. The pathogenesis of the virus is addressed. This is because knowledge of the pathogenesis and strains of the virus has become essential in the study of HIV in vivo dynamics which is still paving ways into extensive research of the ways to contain the disease better. In chapter three the distribution functions of the HIV incubation period and seroconversion time are determined via stochastic models by building on previous work of Lui et al. (1988) and Medley et al. (1988). Also AIDS incidence projection was done using the Backcalculation method. Chapter four deals with the formulation of stochastic model of the dynamics of HIV in an infected individual. Two stochastic models are proposed and analysed for the dynamics of the viral load in a HIV infected person and the multiplication process of the virions inside an infected T4 cell. Also a numerical illustration of the stochastic models derived is given. In chapter five, the T4 cell count which is considered one of the markers of disease progression in HIV infected individual is examined. WHO has recently advocated that countries encourage HIV infected individuals to commence antiretroviral treatments once their T4 cell count is 350 cells per ml of blood. This is because when the T4 cell count is low, the T4 cells are unable to mount an effective immune response against antigens (and any such foreign matters in the body) and consequently, the individual becomes susceptible to opportunistic infections and lymphomas. We developed a stochastic catastrophe model to obtain the mean, variance and covariance of the uninfected, infected and lysed T4 cells; also the amount of toxin produced in a HIV infected person from the time of infection to the present time is derived. A numerical illustration of the correlation structure between uninfected and infected T4 cells, and infected and lysed T4 cells is portrayed. Antiretrioviral treatments were introduced while we await a cure. Treatment with single drug failed due to the fact that HIV evolved rapidly because of its high replication rate. Thus drug resistance to single therapeutic treatment in HIV infected individuals has promoted research into combined treatments. In chapter six a stochastic model under combined therapeutic treatment is derived. Mean numbers of free HIV, infectious free HIV and non-infectious free HIV are obtained. Variance and co-variance structures of our parameters were obtained unlike in previous work of Perelson et al. (1996), Tan and Xiang (1999). / Thesis (PhD)--University of Pretoria, 2009. / Statistics / unrestricted

There are many ways in which gender diversity and sexualness are experienced, spoken of and transacted in India. Recent activism against marginalisation related to sexual and gender nonconformity has led to transformation of some of these idioms into objects that circulate in particular registers of governmentality. In the process, something quite else is created, and this something else portends to speak the truth of 'sexuality in India'. Based on fieldwork carried out between 2005 and 2007 in cities, towns and villages around India, this thesis tells a story of this emergence of 'sexuality' as an aspect of personhood, a political object, a basis for social mobility, a mode of connectedness between people and as a legitimate cause for a movement. The term 'Queer', used variously in India, is a shorthand in some contexts for people who identify as Lesbian, Gay, Bisexual, Transgender, and with South Asian identities such as Hijra, Kothi and Aravani. In others, it refers to a political project challenging norms of heterosexual monogamy, marking a conscious move away from identity-based politics premised on a bio-medical presumption that desire defines personhood. Evoking both these meanings, I examine queer activism as the negotiation of terms of entry of Queer bodies into epidemiological and juridical registers. In relation to the first, I examine interventions of the transnational HIV/AIDS industry that target 'men who have sex with men' – or 'MSM' – the category through which the industry apprehends sexualness between male subjects. I focus on the political-economic conditions of epidemiological knowledge, and on the transformation of idioms of gender and sexualness that its production draws upon. The industry, I argue, is involved in establishing availability of socio-economically marginalised bodies for intervention and research. These relationships of availability are possible because of their promise of social mobility and respectability for queer folk, hitherto despised in masculinist political economies. This mobility is contingent upon the creation and adoption of epidemiologically overdetermined identities which ironically find political significance in being seen as timeless and 'traditional'. The dichotomous being of the 'MSM' - simultaneously the producer and the object of this epidemiological knowledge, implies that the production of this knowledge is predicated upon the ability of queer folk to perform their place in the 'community'. The relationships in the 'field' are already written into the data, and thus the knowledge. Epidemiological knowledge, and the subjects it speaks of, I thus argue, are best understood as articulations of the conditions of their production. The second theme, of Law and the juridical register, opens with an examination of the tensions involved in the production of 'homophobia' as a political object. The disavowal of erotic dimensions in the naming of experiences as 'homophobic violence' is situated in the context of a popular imagination of a worthy juridical subject, and in broader imaginings of power. I then turn to the conditions under which the law, and in particular, Section 377 of the Indian Penal Code, a Victorian anti-sodomy law under which homosexuality is seen to be criminalised, comes to be central to the Queer movement in India. Activism has given Section 377 a 'social life', an awareness of the law in public spheres, amongst law enforcers and branches of the State. Simultaneously, the Law has been inaugurated as a space for the articulation of more diffuse tensions. It has given a tangibility and intelligibility to experiences of exclusion, marginalisation and violence. I then examine a litigation at the High Court of Delhi challenging this law on grounds that it violates Fundamental Rights, focussing on the constitution of a coherent Queer body, cast simultaneously as enumerable, drawing on epidemiological knowledge; and, as capable of instantiation through individual narratives of violation. This project, where a sexuality is ascribed to the citizen-subject, is then juxtaposed with instances where activists actively strip sexualness off of the Queer body in order to make claims to citizenship. This is a cleavage in the Queer movement, an effect of the diversity of bodies it claims to speak of, as, and for, and the conditions under which these diverse bodies seek articulation. Between these projects lies ambiguity, which, I argue, is a precious resource for Queer folk, and for the movement. I suggest a conceptual shift from 'sexuality', (as personhood), to 'sexualness' (where desire flows through subjects without constituting them), argue that the Subject found in registers of governmentality may best be understood in terms of its political economy and distinct from psychic formations, and finally, offer up thoughts for a politics of ambiguity.