A dissertation submitted to the faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science in Medicine in the Division of Human Genetics. / Genetic polymorphisms within the non-recombining portion of Y-chromosome (NRY) preserve a record of human paternal genetic heritage that has persisted to the present, allowing human evolutionary inference, population affinity and demographic history, to be elucidated. To elucidate the geographic origins of the paternal ancestry of the present- day South African (SA) ‘Coloured’ population, a total sample of 167 individuals consisting of Cape Malay (N=54) and ‘Coloured’ groups from Cape Town (N=48) and Johannesburg (N=65) were analysed at 21 binary and eight short tandem repeat (STR) polymorphic loci within NRY. A SA White sample (present study, N=97) as well as other presumed parental populations were included for comparative analysis. Haplotypes constructed using both biallelic haplogroup and STR haplotype data assisted in resolving the geographic regions of origin of Y-chromosome in these groups. Altogether the proportions of African, European and Asian contributions were estimated to be 0%, 18.5% and 46.3% in the Cape Malay, 31.3%, 25% and 20.1% in the Cape ‘Coloureds’, and 24.6%, 40% and 16.9%, in the ‘Coloured’ group from Johannesburg. Those haplotypes that could not be unambiguously resolved to European or Asian origins were referred to as Eurasian lineages, and constituted 35.2%, 22.9% and 18.5% of Y- chromosomes in the Cape Malays, Cape ‘Coloureds’ and Johannesburg ‘Coloureds’, respectively. While the ‘Coloured’ groups currently residing in Cape Town and Johannesburg were not significantly different from each other, both groups were significantly different from the Cape Malay population. This was further supported from the association of these groups in population trees. For the most part, these data corroborate historical data concerning the history of ‘Coloured’ populations, but is the first study to show how males have contributed in shaping the gene pool of the ‘Coloured’ population from South Africa. / WHSLYP2016

Thesis (M.Sc. (Med.))--University of the Witwatersrand, Faculty of Health Sciences, 1998. / The issue of Malagasy ancestry has been controversial, and has still not been completely resolved. The historical, linguistic, archaeological and some genetic evidence points to the fact that modern Malagasy are the descendants of immigrants who arrived on the island over the past 2000 years, from South and Southeast Asia, Africa and the Near East. In more recent centuries, mainly in the twentieth century, there have been significant numbers of Indian, Chinese and French immigrants. In addition, archaeological and historical studies of specific regional populations of Malagasy suggest a complex pattern of internal migration within the island, extending back in time to the first European contacts with the island in the sixteenth century. The 22 Malagasy ethnic groups may be classified as "highland" or "lowland" depending on their geographic distribution on the island. Within the ethnic groups, the founding populations have made different genetic contributions: the highland groups are said to have a greater Indonesian contribution to their ancestry, while the lowlanders have a greater African contribution to their ancestry. Genetic studies on the Malagasy have been limited by small sample sizes, deficiencies in sampling procedures and in the limited number of polymorphisms studied. In light of the paucity of written records, the Department of Human Genetics, SAIMR, has undertaken a large study in Madagascar to reconstruct the biological history of its people, using genetic variation. This thesis forms a part of this study. Variation in the a- and p-globin cluster has been extensively studied in many parts of the world, and has been shown to be population specific, with specific variants having distinct geographical distributions. Thus haemoglobin and its related disorders have been the subject of extensive studies for determining the origin(s) of particular populations. In this study, some of the a- and p-globin variation present in the Malagasy was characterised. Seven RFLPs/HVRs in the a-globin gene cluster and seven RFLPs in the p-globin gene cluster were analysed. The common a- and p-globin gene cluster haplotypes differ between African and Asian populations. Frequencies also vary between populations in a specific geographical regions. The aim of this study was to characterise the haplotypes present in the Malagasy, to provide information on the relative genetic contributions of different populations to the peoples of Madagascar. DNA samples from randomly selected, haematologically normal individuals were analysed. Individuals were chosen from six Malagasy ethnic groups: two “highland” populations (Merina and Betsileo), two “lowland" populations (Antasaka and Tsimiheti) and two populations from the south-west of the island (Mahafaly and Vezo). The groups chosen cover a broad range of Madagascar and thus provide some representation of the Malagasy population as a whole. The number of individuals studied in each ethnic group are as follows: Merina: 88; Betsileo: 78; Antasaka: 67; Tsimiheti: 67; Mahafaly: 26; Vezo: 25. The frequencies of the a- and (B-globin RFLP sites and a-globin HVRs in the Malagasy vere calculated. 5' and 3’ p-globin haplotypes were constructed on the basis of homozygosity. A maximum-likelihood algorithm was used to obtain frequencies of 5’ P-globin haplotypes that could not be assigned on the basis of homozygosity. These data were then subject to statistical analysis. The frequencies of the 5’ p-globin haplotypes (consisting of the five sites Hindi 5' to e, Hindi 11 within Gy and Ay, Hindi within \|/P and 3' to it) were the most informative data set for comparing the Malagasy ethnic groups to each other and to other world populations. Unfortunately, the maximum-likelihood estimates of 5‘ p-globin haplotypes could not be used for comparative analyses due to the lack of similar data in other populations. However the strong correlation between the maximum-likelihood frequencies and the observed frequencies illustrated the ability of the algorithm to determine hapiotype frequencies from otherwise uninformative individuals. 5’ p-globin haplotypes were assigned unambiguously for 248 Malagasy chromosomes. Ten haplotypes were found; of these, nine have been reported previously in other world populations and one has not been reported and hns thus been called “rare” in this study. The frequencies of unambiguous 5’ p-globin haplotypes in the Malagasy and the proposed parental populations were initially analysed with x2 tests. For a more accurate comparison between these populations, genetic distances were calculated and used for the construction of phylogenetic trees, principle component analysis was carried out, and a study of heterozygosity versus distance from the centroid was performed. Admixture estimates of two African populations and one Indonesian population to Malagasy ancestry were calculated. Certain general trends were noted in all the analyses. The results are in agreement with the historical data which provides evidence for both African and Asian contributions to Malagasy ancestry. The highlanders were more closely affiliated to the Indonesian/Polynesian populations, while the south-west groups showed the strongest associations with the African populations. The lowlanders were consistently intermediate in position between the highlanders and the south-west groups, with the Antasaka being slightly more closely related to the African populations than the Tsimiheti. The Malagasy were shown to have high heterozygosities, similar to those of African populations, and this high degree of diversity is probably a reflection of the many sources of ancestry of the Malagasy. The south-west groups were the furthest outliers in the model of heterozygosity versus distance from the centroid, suggesting that these groups are the most genetically admixed of all the Malagasy groups that were studied. Estimates of ancestral population admixture confirmed these trends, with the highlanders having the highest proportional contribution by Indonesians (53%), but the lowest total African contribution (47%), while the south-west groups have the highest Bantu contribution (65%). The Indonesian and African contributions to the lowlanders are intermediate between those to highlanders and south-west groups. Overall the Malagasy subjects included in this study showed a 61% African admixture contribution and a 39% Indonesian admixture contribution. It is hoped that the results obtained in this study will contribute to the larger project concerning the origins of the Malagasy, and that they may be used to shed further light on the much debated issue of Malagasy ancestry.

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Masters of Science June 2015 / Adenium swazicum is currently listed as Critically Endangered due to past and future population declines, which have been estimated to be 80% over three generations. Although 10-20% of the population is present in formal protected areas, no studies have been published on the species population biology and ecology, which are essential to ensure its effective conservation. The broad aim of this research was to investigate the population biology and ecology of Adenium swazicum by investigating factors such as current distribution, population structure, reproductive characteristics, germination, herbivory and current threats. The current distribution of Adenium swazicum was determined by searching all herbarium records on the National Herbarium Pretoria Computerised Information System as well as additional suitable habitat through fieldwork, conducted during the flowering period (October to April) between 2009 and 2011. The current Extent of Occurrence (EOO) and Area of Occupancy (AOO) were determined by incorporating all confirmed localities of Adenium swazicum. To determine the population biology of Adenium swazicum, fifty plants in four representative populations were studied with regards to plant size, extent and intensity of herbivory, flower production as well as follicle and seed production. The reproduction of Adenium swazicum was determined through pollinator observations while the number of flowers and fruit (follicles) produced, as well as fruit and seed set were compared in the four representative populations. Seed viability was determined through tetrazolium staining, while germination experiments were used to determine minimum, maximum and optimum temperature ranges as well as mean germination time. Seedling emergence and establishment were determined for various soil media, depth of seed planting, watering regimes and shading. The current distribution of A. swazicum included 23 localities in South Africa, Swaziland and Mozambique, while the Extent of Occurrence (EOO) was approximately 8 392km² (839 246 ha) and the Area of Occupancy (AOO) was estimated to be 8.5km² (850ha). Although this indicates that A. swazicum might be more widespread than previously believed, the population sizes were all small (between 1 and 141) and most of the populations were still threatened, mostly by habitat destruction and harvesting for medicinal purposes. The research found that adult A. swazicum plants were found to have a high tolerance to natural disturbance (fire, herbivory) and resprout from the underground tuber even if all above ground parts were destroyed. It is however unlikely that seedlings and juveniles will be able to withstand significant impact on the above ground parts since the underground tuber only develops in plants older than 24 months. Despite big and bright floral displays which should attract insect pollinators, low diurnal insect activity was observed around A. swazicum. However, a fast flying Sphingidae (Hawk Moth), which is most likely a pollinator, was observed at A. swazicum flowers at dusk. Small population size and isolation might have been the cause of no reproduction (very few follicles and no seed) in at least one population in 2010. Continued reproduction failure as well as destruction of remaining adult plants by housing developments and collection for medicinal purposes might lead to the local extinction of this population. With sufficient available moisture, high germination success (82 to 90%) for A. swazicum was achieved at temperatures between 20°C and 35°C, without any pre-treatment, and ‘maximum’ germination was reached in less than 90 hours. The cultivation of A. swazicum from seed is highly successful, with different soil media having no apparent influence on seedling emergence and establishment. Seedling emergence was highly dependent on water, and although shading did not influence seedling emergence, seedling establishment/survival was highly dependent on shading. Since seed release from A. swazicum coincides with the start of the rainy season (October), as well as short germination responses, it is highly unlikely that A. swazicum forms persistent soil seed banks. The uncomplicated propagation of A. swazicum has resulted in a significant ex situ collection at the Lowveld National Botanical Garden, with more than 2000 plants (adults and seedlings) grown from seeds which were collected from four different populations over an eight year period. In addition, the Skukuza indigenous nursery in Kruger National Park has more than 250 plants (adults and seedlings) all of which were grown from seed collected in the KNP. These living ex situ collections provide a valuable source of plant material for future restoration projects. Despite an increase in the number of known Adenium swazicum populations, the population sizes are small (1 to 141) and most populations are still threatened by habitat destruction and high levels of exploitation by medicinal plant harvesters. It is therefore recommended that Adenium swazicum remains listed as Critically Endangered (A4acd;B2cb). Criteria A4acd: “An observed, estimated, inferred, projected or suspected population reduction (up to a maximum of 100 years) where the time period must include both the past and future, and where the causes of reduction may not have ceased or, may not be understood, or may not be reversible based on”. This assessment was based on (a) the causes of reduction of Adenium swazicum populations have not ceased and may not be reversible, (c) there is a decline in AOO, EOO and habitat quality; and (d) there is actual, continuing exploitation of A. swazicum. Adenium swazicum also qualifies as CR under criteria B2b(iv,v): “Geographic range in the form of Area of Occupancy (AOO) of <10km² with (b) continuing decline in (iv) number of locations or subpopulations and (v) number of mature individuals”. No immediate management intervention is needed for populations which are located in formal protected areas, although it is recommended that these populations be monitored, especially with regards to reproduction to inform future management decisions. It is possible that low seed viability recorded in population C in 2009 and 2010 could be due to inbreeding depression caused by the destruction of surrounding populations due to sugarcane fields and harvesting of adult plants for medicinal uses. The Low veld National Botanical Garden had collected parental material from populations surrounding population C since 2003; it is recommended that restoration of decimated populations be conducted in secure areas on for example private land and community schools. Lastly, seed collected from various populations should be banked at the Kew Millennium Seed Bank Project, England to ensure viable ex situ collections.

M.Sc.(Med.) (Population Based Field Epidemiology) / Background Assessing HIV incidence over time in a rural population, largely characterized by high levels of migration and poverty is important to understand the dynamics of the spread of HIV infection. Understanding patterns of HIV infection is a key to defining the appropriate strategies for prevention of the disease especially in areas where information on HIV incidence is scarce, such as in Africa and South Africa in particular. Objectives and methods The main objective of this study is to measure the association between migration history and newly acquired HIV infection by sex. The specific objectives are to: (i) quantify median distance of migration by members of the cohort during the period of observation; (ii) measure the association between migration status and acquisition of HIV infection among males and females study participants. The current analysis is based on secondary data collected at the Africa Centre Demographic Surveillance System (DSS) in South Africa. Women aged 15-49 years and men aged 15-54 years were enrolled in the study and tested for HIV between 2003/5 and 2008. A Weibull survival model was used to determine the probability of HIV infection, subject to migration and possible confounders. Results For external migration, the median of external in-migration distance was 53.9 km, with a lower quartile of 27 km and upper quartile of 204 km while the median of external out-migration distance was 104.7 km, with a lower quartile of 52 km and upper quartile of 204 km. The total migration rate among males is 8.8 and for females the rate is 8.2 per 100 person-years (PYO). The majority of external migrants moved to Durban, which appeared to be the most important origin and destination for most migrants. Of the 9300 individuals enrolled in this study, 699 sero-converted. The HIV incidence rate among non-migrants males was 2.0/100 PYO (95% CI, 1.7 – 2.3) and for non-migrants females was 4.1/100 PYO (95% CI, 3.8 – 4.5) while the HIV incidence rates among migrants were higher for females in all categories: 2.0/100 PYO (95% CI, 1.3- 3.1) among internal migrants, 3.8/100 PYO (95% CI, 1.7- 8.5) for external in-migrant and among external out-migrants the HIV incidence rate was 3.2/100 PYO (95% CI, 2.3 – 4.5). For both genders, except internal migration showed a significant risk of HIV acquisition, other types of migration showed no significant association with HIV acquisition. Among other predictors, males who were in the age group 25-29 had the highest hazard of 3.75 times increased risk of HIV acquisition compared to the age group 15-19 [HR = 3.75, 95% CI (2.30 – 6.32), P < 0.001]. Females aged 20-24 years had 43% increased risk of HIV acquisition compared to the those aged 15-19 years [HR = 1.43, 95% CI (1.13 – 1.79), P = 0.002]. For marital status, females who had never been married and not engaged had 71% increased risk of HIV acquisition compared to those who were married, [HR = 1.71, 95% CI (1.09 – 2.68), P = 0.019]. Females with conjugal partners who were always resident and females with conjugal partners who were partial resident had a reduced risk of HIV acquisition of 41% [HR = 0.59, 95% CI (0.36 – 0.95), P = 0.031] and 38% [HR = 0.62, 95% CI (0.40 – 0.96), P = 0.034] respectively. Conclusion Rates of migration vary by age and gender in this cohort of repeat-testers of HIV. Younger individuals migrated more often and the majority of migrants moved to urban centres close to the study area. In terms of HIV incidence, for all covariates, females had higher rates of HIV acquisition than males. External migration does not appear to increase HIV acquisition for this cohort of repeat-testers of HIV, and those who internally migrated had a reduced risk of HIV acquisition. Based on these findings, public health efforts aimed at controlling the spread of HIV infection in this cohort should target at socio-economic condition, sexual behaviour and empowering of women in particular.

Student Number : 9908888R - MSc research report - School of Statistics and Actuarial Science - Faculty of Science / Much research has been devoted towards the understanding of population behaviour. Such understanding has often been furthered through the development of theoretical population models. This research report explores a variety of population models and their implications. The implications of the various models are explored using both analytical results and simulations. Specific aspects of population behaviour studied include gross fluctuation characteristics and extinction probabilities for a population. This research report starts with an overview of Deterministic Models. This is followed by a study of Birth and Death Processes, Branching Processes and Models that incorporate environmental variability. Finally, we study the maximum likelihood approach to population parameter estimation. The more notable theoretical results derived include: the development of models that incorporate the population’s history; models that incorporate discontinuous environmental changes and the development of a means of parameter estimation for a Stochastic Differential Equation.

La vincristine est un vinca-alcaloïde très largement utilisé et reste incontournable dans la prise en chargethérapeutique de nombreux cancers, notamment en pédiatrie. Ce médicament présente une neurotoxicitédose-limitant, très variable d’un individu à l’autre, difficilement prévisible, ayant ainsi des conséquencescliniques directes sur l’efficacité thérapeutique. Cette variabilité pourraient avoir une originepharmacocinétique et pharmacogénétique, en partie liée au métabolisme hépatique intense de la vincristinepar les enzymes CYP3A4 et CYP3A5 et à son transport par la P-glycoprotéine (codée par le gène ABCB1).En effet, de nombreux polymorphismes génétiques des gènes CYP3A4, CYP3A5 et ABCB1 ont été décritsdont certains sont associés à d’importantes différences d’expression et/ou de fonctionnalité de la protéine.Nous avons donc développé une méthode de dosage sensible et hautement spécifique de la vincristine parLC-MSMS, adaptée à la réalisation d’une étude de pharmacocinétique-pharmacogénétique dans unepopulation pédiatrique atteinte de tumeurs solides.Nous avons montré que les différents facteurs démographiques, thérapeutiques et génétiques étudiés(allèles CYP3A5*3, CYP3A4*1B ; mutations ABCB1 C1236T, G2677T(A) et C3435T) ne sont pasprédictifs de la variabilité de la pharmacocinétique de la vincristine observée dans notre populationpédiatrique. Ces résultats sont renforcés par l’observation d’une large variabilité pharmacocinétique entreles cures pour un même patient, qui ne peut être expliquée par des facteurs génétiques. Nous avons pu chezcertains patients, évaluer l’accumulation intracellulaire de la vincristine. Une importante variabilité estégalement retrouvée au niveau cellulaire et nos résultats montrent deux profils d’accumulationintracellulaire de vincristine très distincts qui pourraient avoir une origine génétique. En effet, les patientsporteurs du génotype hétérozygote d’ABCB1 présentaient une tendance à une plus forte accumulation surles temps précoces.Néanmoins, l’incidence de survenue d’une neurotoxicité n’a pas non plus été associée à des différencesd’exposition plasmatique ou d’accumulation intracellulaire de vincristine ou encore aux polymorphismesgénétiques étudiés du CYP3A4, CYP3A5 et d’ABCB1 dans notre population. La pertinence clinique d’unedifférence d’accumulation intracellulaire de la vincristine reste à être évaluée sur un effectif beaucoup plusimportant. La variabilité de la neurotoxicité de la vincristine ne semble donc pas être prédite par desfacteurs génétiques affectant la pharmacocinétique et pourrait donc avoir notamment une originepharmacodynamique, liée à une modification de sa sensibilité chez certains patients. / Vincristine is a natural vinca-alkaloid widely used in many chemotherapy regimens for paediatric tumourdiseases. The most frequent and clinically relevant side-effect of vincristine is a dose-limitingneurotoxicity which is unpredictable and characterized by a great variability between patients. Thisvariability could have a pharmacokinetic and pharmacogenetic origin, partly due to the intense hepaticmetabolism of vincristine through both CYP3A4 and CYP3A5 and a transport by P-glycoprotein (encodedby the ABCB1 gene). Indeed, several genetic polymorphisms have been described for CYP3A4, CYP3A5and ABCB1 which could affect the expression and/or the functionality of the protein. We have firstdeveloped a sensitive and highly specific LC-MS/MS method for vincristine quantification, suitable for apharmacokinetics-pharmacogenetics study in paediatric patients treated for solid tumours diseases.Our results showed that demographic, therapeutic and genetic factors assessed (CYP3A5*3, CYP3A4*1Balleles and ABCB1 C1236T, G2677T (A) and C3435T mutations) are not predictive of vincristinepharmacokinetics variability observed in our paediatric population. These results are enhanced by theobservation of a wide inter-course variability which cannot be explained by genetic factors. In somepatients, we were able to evaluate the vincristine intracellular concentration and we observed similarly alarge inter-patient variability. Two populations emerge according with the intracellular vincristineaccumulation and this dichotomic distribution could have a genetic origin. Indeed, a tendency to a greateraccumulation of intracellular vincristine was observed in patients with ABCB1 CGC-TTT diplotype in theearly post-dose period.Nevertheless, the incidence of neurotoxicity in our population has not been associated to differences inplasma exposure and intracellular accumulation of vincristine and to the assessed genetic polymorphismsof CYP3A4, CYP3A5 and ABCB1. The clinical relevance of differences in the intracellular accumulation ofvincristine remains to be evaluated on a larger cohort of patients. The variability of vincristineneurotoxicity does not seem to be explained by genetic factors affecting its pharmacokinetics and thereforecould have a pharmacodynamic origin, probably linked to a modification of vincristine sensitivity inpatients.

論文(碩士)--香港中文大學, 1974. / Ms. / Includes bibliographical references (l. 93-97). / Thesis (M.A.)--Xianggang Zhong wen da xue, 1974. / Chapter 第一章 --- 平城 / Chapter 第一節 --- 平城的創建　 --- p.1 / Chapter 第二節 --- 平城居民數字的估計 --- p.14 / Chapter 一 --- 道武帝以前的情形 --- p.15 / Chapter 二 --- 道武帝與明元帝時代 --- p.17 / Chapter 三 --- 太武帝時代　 --- p.22 / Chapter 四 --- 文成帝與献文帝時代 --- p.26 / Chapter 五 --- 孝文帝時代 --- p.27 / Chapter 第三節 --- 平城的經濟情況　 --- p.29 / Chapter 一 --- 前言 --- p.29 / Chapter 二 --- 平城前期是農業與畜牧游獵並重 --- p.31 / Chapter 三 --- 平城後期是農業重於游獵　 --- p.44 / Chapter 四 --- 北魏時代平城附近的自然資源　 --- p.46 / Chapter A --- 鹽 --- p.46 / Chapter B --- 漁 --- p.47 / Chapter 五 --- 結論 --- p.48 / Chapter 第二章 --- 洛陽 / Chapter 第一節 --- 北魏洛陽城郭圖觀念的形成 --- p.58 / Chapter 第二節 --- 繪北魏洛陽城郭圖後新發現諸問題 --- p.62 / Chapter 一 --- 坊里數目很難與古籍所載契合 --- p.62 / Chapter 二 --- 大市周圍諸里秩序或有掉亂　 --- p.63 / Chapter 三 --- 不能入圖的坊里 --- p.64 / Chapter 四 --- 靈臺位置　 --- p.65 / Chapter 第三節 --- 古籍所載輿閻實測图中遺跡相符合處 --- p.67 / Chapter 第四節 --- 關於北魏洛陽城郭圖的一點說明　 --- p.69 / Chapter 第五節 --- 北魏都洛時代洛陽的居民數字 --- p.71 / Chapter 第六節 --- 洛陽的都市性質 --- p.76 / Chapter 一 --- 政治性都市 --- p.76 / Chapter 二 --- 計劃性都市　 --- p.76 / Chapter 三 --- 消費性都市 --- p.78 / Chapter 第三章 --- 鄴都 / Chapter 第一節 --- 鄴都的人口 --- p.82 / Chapter 第二節 --- 鄴都的經濟 --- p.86 / 結論　 --- p.91 / 參攷書目　 --- p.93 / Chapter 附图一 --- 水經濟图所附之平城图 / Chapter 二 --- 閻文儒：漢魏洛陽城實測图 / Chapter 三 --- 北魏洛陽城郭图 / Chapter 四 --- 水經濟圖所附之鄴城图

Yung Wun Na. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 60-62). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Statistical Modeling --- p.4 / Chapter 2.1 --- Capture Recapture Model --- p.4 / Chapter 2.1.1 --- Petersen Estimate --- p.5 / Chapter 2.1.2 --- Chapman Estimate --- p.8 / Chapter 2.2 --- The Bootstrap Method --- p.9 / Chapter 2.2.1 --- The Bootstrap Percentile Method --- p.10 / Chapter 2.3 --- The Double Bootstrap Method --- p.12 / Chapter 2.3.1 --- The Robbins-Monro Method --- p.12 / Chapter 2.3.2 --- Confidence Interval generated by the Robbins-Monro Method --- p.13 / Chapter 2.3.3 --- Three Different Approaches --- p.16 / Chapter 3 --- Empirical Study --- p.19 / Chapter 3.1 --- Introduction --- p.19 / Chapter 3.2 --- Double Bootstrap Method --- p.20 / Chapter 3.2.1 --- Petersen Estimate --- p.20 / Chapter 3.2.2 --- Chapman Estimate --- p.27 / Chapter 3.2.3 --- Comparison of Petersen and Chapman Estimates --- p.31 / Chapter 3.3 --- Conclusion --- p.33 / Chapter 4 --- Simulation Study --- p.35 / Chapter 4.1 --- Introduction --- p.35 / Chapter 4.2 --- Simulation Results of Double Bootstrap Method --- p.36 / Chapter 5 --- Conclusion and Discussion --- p.52 / References --- p.60

The hard tick Ixodes ricinus is one of the most important species of disease vectors worldwide. It transmits a variety of pathogens, including spirochaetes that are the causative agent of Lyme borreliosis (LB) in humans. This study aimed at analysing different aspects of the ecology, molecular evolution, and microbial associations of I. ricinus. A novel scheme for the phylogenetic analysis and genotyping of I. ricinus was established as part of this study. Phylogeographic clustering of I. ricinus samples fromdifferent European countries was observed, while samples from two different sites inSouthwest England did not show spatial differentiation. The ecology and host abundance in these two habitats was assessed. Differences in the density of questing ticks and in the abundance of rodent hosts were observed. Both sites exhibited low densities of rodents and of ticks infesting them. A blood meal analysis revealed high proportions of mixed feedings and showed artiodactyls to be a main host group for immature I. ricinus ticks from Britain. The prevalence rates of Wolbachia endobacteria in British I. ricinus samples were higher than rates found in samples from other European countries. The unique endosymbiont Midichloria was detected in all female I. ricinus ticks that were screened. A newly developed multi gene analysis of Midichloria samples from six European countries showed a largely coordinated phylogeography with their tick hosts. Taken together, the findings of this thesis demonstrate that British I. ricinus ticks differ from their European counterparts in several ways, which has implications for the epidemiology of infectious diseases transmitted by this vector.

This research encompasses the fields of social protection and migration through an empirical study of the Mexican conditional cash-transfer (CCT) programme, Oportunidades, in two indigenous locations. The thesis looks at the way(s) in which Oportunidades and migration, both international and domestic, influence each other. It focuses on the decision to migrate of individuals – in particular of former and current beneficiaries of the programme – and offers a methodological approach that is different to previous studies on this topic. The thesis employs both qualitative and ethnographic data on the mutual effects of CCTs and migration through multi-sited research covering the high region of the Mixes in Oaxaca, Oaxaca City and Mexico City, and in California, USA. The results show that: - the outcome of the influence of Oportunidades on the decision to migrate is very dependent on contextual variables, mainly the migration situation in each village, the social and cultural norms around the purpose and meaning of migration, and the circumstances of beneficiaries' households. The outcome of Oportunidades was mediated by what the individual household and community considered as the means to achieve social mobility, which differed across the two main localities of study; - the allocation of remittances, both international and internal, had an influence not only on the households but also on the norms and values of the society more broadly, through the annual cargos or local-council elections and the aspirations of beneficiaries; and finally that - the transition from more years of education to skilled jobs, as expected by Oportunidades, is not straightforward. This thesis explores how these transitions take place in reality and the different meanings and paths to social mobility they have for beneficiaries.