Magister Scientiae (Medical Bioscience) - MSc(MBS) / Aim: Leukocytes are the major source of reactive oxygen species (ROS) in the ejaculate and contribute to up to 30% of male infertility. ROS have been associated with markers of apoptosis such as sperm DNA damage, externalization of phosphatidylserine and caspase-3 activation. Therefore, this study aimed at investigating the impact male genital tract infections/inflammations on the induction of apoptosis in spermatozoa.Materials and Methods: Semen samples were obtained from 60 men consulting for fertility problems at the Reproductive Biology Unit, University of Stellenbosch at Tygerberg Academic Hospital, and Vincent Pallotti Hospital (Cape Town, South Africa). To investigate the relationship between male genital tract infection and sperm apoptosis, the following were measured: semen parameters including sperm count, motility and forward progression; oxidative status in the ejaculate by evaluating the concentration of seminal leukocytes, ROS production in the ejaculate,generation of O2-• and H2O2 by spermatozoa, and the activity of reduced glutathione(GSH) in sperm; sperm apoptotic markers by measuring mitochondrial membrane potential (Δψm), caspase-3/7 activation, and DNA fragmentation (TUNEL).Results: The concentration of seminal leukocytes had a significant positive correlation with ROS production in the ejaculate (ρ=0.378; P=0.0064), sperm O2-• production (ρ=0.336; P=0.0098), and caspase-3/7 activation in sperm (ρ=0.527;P<0.0001). Furthermore, at the cutoff value of ≥0.25×106 leukocytes/mL of semen,the concentration of peroxidase-positive cells correlated significantly with sperm GSH activity (ρ=0.718; P=0.008), the percentage of sperm with disrupted Δψm(ρ=0.465; P=0.043), caspase-3/7 activation in sperm (ρ=0.794; P=0.001), and the percentage of sperm with fragmented DNA (ρ=0.563; P=0.017). ROS production in the ejaculate, besides the association with seminal leukocytes, was also correlated with the sperm count (ρ= -0.296; P=0.033), sperm GSH activity (ρ=0.577; P<0.0001),caspase-3/7 activation in sperm (ρ=0.487; P=0.0005), and sperm DNA fragmentation(ρ=0.331 P=0.0171). Caspase-3/7 activation was strongly correlated with oxidative stress in both, the ejaculate and in spermatozoa; although this parameter was not correlated with sperm Δψm and DNA fragmentation. Sperm O2-•, which had a link with seminal leukocyte concentration, was significantly correlated to sperm Δψm(P=0.0098), as was sperm GSH activity (P=0.0055). Sperm DNA fragmentation was positively correlated with ROS in the ejaculate and sperm H2O2-production(P=0.039). Conclusions: Excessive ROS in the ejaculate, mainly a consequence of seminal leukocytes, is not only linked to internal generation of O2-•, but also to sperm DNA fragmentation and the activation of effector caspases. Moreover, even in nonleukocytospermic patients with ≥0.25×106 leukocytes/mL of semen, oxidative stresscan occur which can trigger apoptosis, caspase-3/7 activation, and induce sperm DNA fragmentation. Therefore, it is possible that male genital tract infection, the major cause of leukocyte infiltration in the male reproductive tract, can induce apoptosis, of which the observed sperm DNA fragmentation is a late feature.

Current theories in psychology now suggest that behaviours that were primarily associated with psychotic disorders, such as delusional experiences, can be observed in the healthy general population (van Os, Linscott, Myin-Germeys, Delespaul and Krabbendam, 2009). Delusions, a common symptom of schizophrenia, have been associated with a tendency to jump to conclusions. In simpler terms, it has been discussed that those that experience delusions will reach final decisions earlier than controls upon the basis of little evidence (Huq, Garety and Hemsley, 1988). The aim of the research was to investigate the factors that may moderate this susceptibility to jump to conclusions amongst the sub-clinical range of delusional thinking amongst the distinct construct measures of the Peters et al. Delusions Inventory (PDI: Peters, Day and Garety, 1996). Numerous studies were conducted to investigate: intelligence, probability calculation ability, experimental task design and task delivery upon the emergence of the jump to conclusions bias (Chapters II-VI). Moderator analyses identified that task design and task delivery were strong predictors of the quantity of information requested prior to finalising a decision; with restricted data gathering occurring with the use of face-to-face abstract tasks (Chapter III and VI B). When tasks included neutral and emotionally-unstimulating material, a data gathering bias was either not observed (Chapter II) or data gathering was enhanced amongst those with high belief conviction. Perceived life stress, perceived task stress and specific reasoning styles were investigated in an attempt to explain the situation-specific differences (Chapters VII and VIII). It was concluded in the General Discussion that delusional thinking appears to be associated with hasty decision making, under specific situational circumstances and can differ between the distinct constructs of the PDI measure (Peters et al. 1996). Sub-clinical delusional ideation is an overall summation of belief distress, preoccupation and conviction. The current research argues that the three psychological dimensions of delusional belief can influence decision making uniquely; specifically in relation to the emergence of a data gathering bias.

This thesis explores the decision making styles demonstrated by people with anorexia. It is presented as three papers: 1) a literature review; 2) an empirical study and 3) a personal reflection on the processes involved in conducting the research and critical appraisal of the issues which emerged. The literature review in Paper 1 systematically explored the existing research that examined decision making in disordered eating populations. Twenty seven papers were reviewed and their findings synthesised to develop a comprehensive overview of decision making across a spectrum of disordered eating populations. Parallels in decision making across diagnostic categories were identified, and the relationship between decision making and clinical, personality and demographic variables was also explored. Methodological quality of studies was reviewed; recommendations for future research were also identified. Broadly, the findings indicated that similar styles of decision making appear evident in anorexia and bulimia. No characteristically different decision making patterns were demonstrated by people with eating disorder-not otherwise specified or by people recovered from anorexia. The evidence regarding nature of decision making in obesity and binge eating disorder was less conclusive. The empirical study conducted in Paper 2 endeavoured to enhance our understanding of the nature of decision making in disordered eating. The study examined a specific decision making bias i.e. the ‘jumping to conclusions’ bias in people with anorexia. The study also explored whether eating disorder related beliefs in anorexia could be considered to be of ‘delusional’ proportions. The results indicated that compared with a healthy control group, people with anorexia did not display a ‘jumping to conclusions’ bias. They did not display a tendency to make decisions on the basis of little evidence. The majority of individuals with anorexia did demonstrate limited insight into their eating disorder related beliefs, though only a minority subgroup held beliefs that could be considered ‘delusional’. Methodological limitations and clinical implications of the findings are discussed. The third paper provides a personal and critical reflective account of the processes involved in conducting both the literature review and the scientific study. It critically appraises aspects of the research process including strengths and limitations of both studies. Implications for clinical practice, replication and directions for future research are also identified. This paper also includes personal reflections on the approaches used and the challenges encountered within these.

A Critical Examination of A.J. Ayer's Moral Philosophy Ayer' s overall notion of ethics is that all normative ethical statements are cognitively meaningless. This thesis is an attempt to refute this claim. Ayer's notion is based, I think, on his following two convictions: ( i ) ethical statements are purely emotive, (ii) reasoning from factual premises to ethical conclusions is neither deductive nor inductive. Ethical statements are, according to Ayer, purely emotive because they are pure expressions of the feelings and emotions of the speaker. This means that ethical statements do not even report the speaker's mental state. I have shown that there are some voluntarily uttered ethical statements which are not expressive and hence that some ethical statements are not purely emotive. The controversy whether ethical statements can be deduced formally from factual statements is very old. I have switched the problem to a different direction by showing that the induction/deduction dichotomy is not adequate for reasoning. Other reasoning processes, like informal reasoning, allow one to deduce ethical conclusions from factual premises. It is also shown how Ayer's criterion of meaning, namely the verification principle, renders ethical statements meaningful. Finally, I have defended universalistic act-utilitarianism as a cognitive theory of ethics. / Thesis / Master of Arts (MA)

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In our experience of teaching Calculus to engineering undergraduates we have had to grapple with many different problems. A major hurdle has been students’ inability to appreciate the importance of the theory. In their view the theoretical part of mathematics is separate from the computing part. In general, students also believe that they can pass their exams even though they do not have a real understanding of the theory behind the problems they are required to solve. In an effort to surmount these difficulties we tried to find ways to make students better understand the theoretical part of Calculus. This paper describes our experience of teaching Calculus. It reports on the continuation of our previous research.

This thesis consists of a summary and five papers, dealing with self-normalized sums of independent, identically distributed random variables, and three-decision procedures for directional conclusions. In Paper I, we investigate a general set-up for Student's t-statistic. Finiteness of absolute moments is related to the corresponding degree of freedom, and relevant properties of the underlying distribution, assuming independent, identically distributed random variables. In Paper II, we investigate a certain kind of self-normalized sums. We show that the corresponding quadratic moments are greater than or equal to one, with equality if and only if the underlying distribution is symmetrically distributed around the origin. In Paper III, we study linear combinations of independent Rademacher random variables. A family of universal bounds on the corresponding tail probabilities is derived through the technique known as exponential tilting. Connections to self-normalized sums of symmetrically distributed random variables are given. In Paper IV, we consider a general formulation of three-decision procedures for directional conclusions. We introduce three kinds of optimality characterizations, and formulate corresponding sufficiency conditions. These conditions are applied to exponential families of distributions. In Paper V, we investigate the Benjamini-Hochberg procedure as a means of confirming a selection of statistical decisions on the basis of a corresponding set of generalized p-values. Assuming independence, we show that control is imposed on the expected average loss among confirmed decisions. Connections to directional conclusions are given.

Development cooperation is nowadays a highly discussed topic, especially in the context of its effectiveness. In the past years the European Union and the Organization for economic cooperation and development adopted several documents concerning aid effectiveness and possible ways of its improvement. The aim of this thesis is to find out, in the case of selected states (France, Sweden, and the Czech Republic), if they implement the commitments resulting from these documents into their national development policies and if they carry out their development cooperation in compliance with them. Since the commitments in this area overlap between the two organizations and both of them are trying to influence the states to fulfill their commitments, this thesis will also try to identify which of these organizations has a greater influence on the chosen states. Keywords EU development policy, Council Conclusions, Member States, OECD, aid effectiveness, financial commitments

In our experience of teaching Calculus to engineering undergraduates we have had to grapple with many different problems. A major hurdle has been students’ inability to appreciate the importance of the theory. In their view the theoretical part of mathematics is separate from the computing part. In general, students also believe that they can pass their exams even though they do not have a real understanding of the theory behind the problems they are required to solve. In an effort to surmount these difficulties we tried to find ways to make students better understand the theoretical part of Calculus. This paper describes our experience of teaching Calculus. It reports on the continuation of our previous research.