Toxoplasma gondii, protozoaire ubiquitaire chez les mammifères et les oiseaux, est l’agent étiologique de la toxoplasmose, une maladie posant un réel problème de santé publique dans le monde avec environ 200 000 nouveaux cas de toxoplasmose congénitale chaque année. Il a été montré que la sévérité clinique de la toxoplasmose variait en fonction des régions géographiques, avec en particulier l’Amérique du Sud qui paie le plus lourd tribu de cette maladie. Malheureusement, les mécanismes de ces disparités géographiques sont encore peu compris et l’origine géographique ainsi que l'histoire évolutive du pathogène sont encore incertaines. Une collection mondiale de 168 isolats de T. gondii recueillis dans 13 populations de 5 continents a été séquencée pour cinq fragments de gènes (140 single nucleotide polymorphisms à partir de 3153 bp par isolat). La phylogénie basée sur les méthodes de Maximum de vraisemblance avec une estimation de l’âge du plus récent ancêtre commun (TMRCA) et des analyses géostatistiques ont été réalisées afin d’inférer l’origine hypothétique de T. gondii. Nous montrons que les souches actuelles de ce parasite ont vraisemblablement évolué à partir d’un ancêtre Sud-Américain il y a environ 1,5 million d’années et avons reconstruit la propagation mondiale du pathogène qui a suivi. Cette émergence est beaucoup plus récente que l’apparition de la forme ancestrale de T. gondii il y a environ 11 Ma et est postérieure à l’arrivée des félidés dans cette partie du monde. Nous proposons que la lignée ancestrale de T. gondii ait été introduite en Amérique du Sud avec les félidés et que l’évolution de l’infectivité orale des kystes tissulaires à travers le carnivorisme ainsi que la diversification des félidés dans cette région du monde a permis l'apparition d'une nouvelle souche ayant une capacité de transmission beaucoup plus efficace que la lignée ancestrale, ce qui lui a permis de la supplanter et d’avoir une distribution pandémique. / Toxoplasma gondii, a protozoan found ubiquitously in mammals and birds, is the etiologic agent of toxoplasmosis, a disease causing substantial Public Health burden worldwide, including about 200,000 new cases of congenital toxoplasmosis each year. Clinical severity has been shown to vary across geographical regions with South America exhibiting the highest burden. Unfortunately, the drivers of these heterogeneities are still poorly understood, and the geographical origin and historical spread of the pathogen worldwide are currently uncertain. A worldwide sample of 168 T. gondii isolates gathered in 13 populations was sequenced for five fragments of genes (140 single nucleotide polymorphisms from 3,153 bp per isolate). Phylogeny based on Maximum likelihood methods with estimation of the time to the most recent common ancestor (TMRCA) and geostatistical analyses were performed for inferring the putative origin of T. gondii. We show that extant strains of the pathogen likely evolved from a South American ancestor, around 1.5 million years ago, and reconstruct the subsequent spread of the pathogen worldwide. This emergence is much more recent than the appearance of ancestral T. gondii, believed to have taken place about 11 My ago, and follows the arrival of felids in this part of the world. We posit that an ancestral lineage of T. gondii likely arrived in South America with felids and that the evolution of oral infectivity through carnivorism and the radiation of felids in this region enabled a new strain to outcompete the ancestral lineage and undergo a pandemic radiation.

This thesis examines the relevancy of south-west portals with regards to their potential usage in post-burial ritual activity with particular focus on the deposition of sacrificial offerings. South-west portals are a type of stone constructions found on the edges of mounds and stone settings in eastern central Sweden usually dating to the Viking Age (c. 750-1100 CE). As many as possible of all excavated south-west portals are accounted for. The find materials in south-west portals as well as their accessibility are assessed in accordance with the reasoning that long-term grave cult would result in repeated sacrificial depositions and that the portals would have had to have been accessible for such sacrifices to have been conducted. There is no clear evidence of south-west portals having been used for deliberate sacrificial depositions. Some portals would have been inaccessible and most non-funerary find assemblages were likely non-deliberate or at least nonindicative of repeated sacrifices. South-west portals were likely more relevant in funerary rites of passage or potentially odd instances of necromancy rather than in sacrifices connected to ancestor worship. / Denna avhandling undersöker relevansen av sydvästportar med avseende på deras potentiella användning i rituella aktiviteter efter begravningen med särskilt fokus på deponering av offergåvor. Sydvästportar är en typ av stenkonstruktioner som förekommer på kanterna av högar och stensättningar i östra Mellansverige, vanligtvis daterade till vikingatiden (ca 750-1100 e.v.t.). Så många som möjligt av alla utgrävda sydvästportar redovisas. Fyndmaterialet i sydvästportar samt deras tillgänglighet bedöms utifrån resonemanget att långvarig gravkult skulle resultera i upprepade offerdepositioner och att portarna skulle ha behövt vara tillgängliga för sådana offer att genomföras. Det finns inga tydliga bevis för att sydvästportar har använts för avsiktliga offerdepositioner. Vissa portar skulle ha varit otillgängliga och de fyndmaterialansamlingar som inte var gravar var sannolikt oavsiktliga eller åtminstone icke indikativa på upprepade offerriter. Sydvästportar var sannolikt mer relevanta i begravningsriter eller potentiellt udda fall av nekromanti snarare än i offer kopplade till förfädersdyrkan.

Microorganisms play crucial roles in aquatic environments in determining ecosystemstability and driving the turnover of elements essential to life. Understanding thedistribution and evolution of aquatic microorganisms will help us predict how aquaticecosystems will respond to Global Change, and such understanding can be gained bystudying these processes of the past. In this project, we investigate the evolutionaryrelationship between brackish water bacteria from the Baltic Sea and Caspian Seawith freshwater and marine bacteria, with the goal of understanding how brackishwater bacteria have evolved. 11,276 bacterial metagenome-assembled genomes(MAGs) from seven metagenomic datasets were used to conduct a comparativeanalysis of freshwater, brackish and marine bacteria. When clustering the genomes bypairwise average nucleotide identity (ANI) at the approximate species level (96.5%ANI), the Baltic Sea genomes were more likely to form clusters with the Caspian Seagenomes than with Swedish lakes genomes, even though geographic distancesbetween Swedish lakes and the Baltic Sea are much smaller. Phylogenomic analysisand ancestral state reconstruction showed that approximately half of the brackishMAGs had freshwater ancestors and half had marine ancestors. Phylogeneticdistances were on average shorter to freshwater ancestors, but when subsampling thetree to the same number of freshwater and marine MAG clusters, the distances werenot significantly different. Brackish genomes belonging to Acidimicrobiia,Actinobacteria and Cyanobacteriia tended to originate from freshwater bacteria, whilethose of Alphaproteobacteria and Bacteroidia mainly had evolved from marinebacteria. / Mikroorganismer spelar avgörande roller i akvatiska ekosystem där de driverkretsloppen av näringsämnen. En ökad förståelse för hur mikroorganismer anpassarsig till miljöförändringar är viktigt för att förutsäga hur akvatiska ekosystem kommeratt förändras som en konsekvens av global uppvärmning, och sådan förståelse kanuppnås genom att studera tidigare skeenden i evolutionen. I detta projekt undersökervi det evolutionära förhållandet mellan brackvatten-bakterier från Östersjön ochKaspiska havet med sötvattens- och marina bakterier, med målet att förstå hurbrackvatten-bakterier har utvecklats. 11,276 bakteriella arvsmassor somrekonstruerats med metagenomik från sju data-set användes för att utföra enjämförande analys av bakterie-genom från söt-, brack och havsvatten. Klustring avgenomen baserat på parvis genomsnittlig nukleotididentitet (ANI) på ungefärligartnivå (96,5% ANI), grupperade Östersjöns bakterier tillsammans med Kaspiskahavets bakterier mer än med bakterier från svenska sjöar, trots att det geografiskaavståndet mellan svenska sjöar och Östersjön är mycket mindre. Fylogenetisk analysvisade att ungefär hälften av brackvatten arterna hade anfäder från sötvatten ochhälften från havsvatten. De fylogenetiska avstånden var i genomsnitt kortare tillanfaderna i sötvatten, men när man reducerade trädet till att ha samma antal sötvattenoch marina arter var avstånden inte längre signifikant olika. Brackvatten-arter somtillhörde Acidimicrobiia, Actinobacteria och Cyanobacteriia tenderade att härstammafrån sötvattenbakterier, medan de från Alphaproteobacteria och Bacteroidia främsthärstammade från marina bakterier.

Pseudomonas syringae is a common foliar plant pathogenic bacterium that causes diseases on many crop plants. We hypothesized that today's highly virulent P. syringae crop pathogens with narrow host range might have evolved after the advent of agriculture from ancestral P. syringae strains with wide host range that were adapted to mixed plant communities. The model tomato and Arabidopsis pathogen P. syringae pv. tomato (Pto) DC3000 and its close relatives isolated from crop plants were thus selected to unravel basic principles of host range evolution by applying molecular evolutionary analysis and comparative genomics approaches. Phylogenetic analysis was combined with host range tests to reconstruct the host range of the most recent common ancestor of all analyzed strains isolated from crop plants. Even though reconstruction of host range of the most recent common ancestor of all analyzed strains was not conclusive, support for this hypothesis was found in some sub-groups of strains. The focus of my studies then turned to Pto T1, which was found to represent the most common P. syringae lineage causing bacterial speck disease on tomato world-wide. Five genomes were sequenced and compared to each other. Identical genotypes were found in North America and Europe suggesting frequent pathogen movement between these continents. Moreover, the type III-secreted effector gene hopM1 was found to be under strong selection for loss of function and non-synonymous mutations in the fliC gene allowed to identify a region that triggers plant immunity. Finally, Pto T1 was compared to closely related bacteria isolated from snow pack and surface water in the French Alps. Recombination between alpine strains and crop strains was inferred and virulence gene repertoires of alpine strains and crop strains were found to overlap. Alpine strains cause disease on tomato and have relatively wider host ranges than Pto T1. The conclusion from these studies is that Pto T1 and other crop pathogens may have evolved from ancestors similar to the characterized environmental strains isolated in the French Alps by adapting their effector repertoire to individual crops becoming more virulent on these crops but losing virulence on other plants. / Ph. D.

The world has become more and more religiously plural. It is therefore essential to acknowledge the meaningful aspects in the essence of all religions, including African Religion. The dissertation seeks to highlight the concept, ”continuity of life” in African Religion. Special emphasis is placed on the Zulus due to the vastness of the African continent. Three areas are investigated to show that there is the belief in life after death in African Religion, as it is the case with all great world religions, such as Judaism, Islam and Christianity. These are the sacredness of life, marriage with the gift of children as a blessing from the ancestors, as well as rites and ceremonies associated with death which show that the dead are still alive in a mysterious form. The conclusion is therefore that African Religion has a world status and should be included amongst the great world religions. / Religious Studies and Arabic / M. Th. (Biblical Studies)

This qualitative study focuses on two questions: a) Do present-day Shona still subscribe to the world-view of their ancestors? b) How does this world-view relate to that of the modern (Western) world? Interviews were conducted with government representatives, chiefs in Masvingo Province and people in all walks of life. Virtually all interviewees, even when participating in the "modern" sector (including Christianity), still subscribe to the traditional system. Government, however, has adopted the model of the pre-Independence government, with some concessions to tradition. The traditional world-view (emphasising its key symbols, blood and soil) and the history of the two dominant tribes in Masvingo Province are outlined. A case study of a current chieftaincy dispute illustrates the dilemma. Conclusion: searching dialogue between the two belief systems is needed to resolve the potentially creative ambivalence. Some key issues are suggested as starting points for such dialogue. / M.A. (Religious Studies)

The world has become more and more religiously plural. It is therefore essential to acknowledge the meaningful aspects in the essence of all religions, including African Religion. The dissertation seeks to highlight the concept, ”continuity of life” in African Religion. Special emphasis is placed on the Zulus due to the vastness of the African continent. Three areas are investigated to show that there is the belief in life after death in African Religion, as it is the case with all great world religions, such as Judaism, Islam and Christianity. These are the sacredness of life, marriage with the gift of children as a blessing from the ancestors, as well as rites and ceremonies associated with death which show that the dead are still alive in a mysterious form. The conclusion is therefore that African Religion has a world status and should be included amongst the great world religions. / Religious Studies and Arabic / M. Th. (Biblical Studies)

This qualitative study focuses on two questions: a) Do present-day Shona still subscribe to the world-view of their ancestors? b) How does this world-view relate to that of the modern (Western) world? Interviews were conducted with government representatives, chiefs in Masvingo Province and people in all walks of life. Virtually all interviewees, even when participating in the "modern" sector (including Christianity), still subscribe to the traditional system. Government, however, has adopted the model of the pre-Independence government, with some concessions to tradition. The traditional world-view (emphasising its key symbols, blood and soil) and the history of the two dominant tribes in Masvingo Province are outlined. A case study of a current chieftaincy dispute illustrates the dilemma. Conclusion: searching dialogue between the two belief systems is needed to resolve the potentially creative ambivalence. Some key issues are suggested as starting points for such dialogue. / M.A. (Religious Studies)

The Kyrgyz are a Mongolian, Turkic ethno-linguistic people group. The political and social changes of the post-soviet times have led to a great religious openness among the Kyrgyz. Within one decade the nunber of Kyrgyz Christians has grown from few dozens to over 3000. The intention of this work was to analyze the conversion process of the Kyrgyz converts to Christianity and to apply the results to further missiological activity. The religious background of the Kyrgyz, which is heavily influenced by Folk Islam, was presented in the first chapter of the paper. In the second chapter, interviews collected from Kyrgyz Christians were evaluated. The third chapter summarizes the most important findings of the work and makes them applicable for missionary work. The precise knowledge of the religious background of the Kyrgyz and intercultural communication that it is based upon it can essentially dismantle barriers for the acceptance of the gospel. / Christian Spirituality, Church History and Missiology / M. Th. (Missiology)

The study sets to establish trends with regard to the role of the praise singer, the changes with regard to the traditional praise singer's rendition/performance and the material or content of his/her poetry. Thus the study highlights the distinction observed between the praise singer of the past and the present praise singer. The study also shows that the praise singer's performance, in terms of his/her role and content, is in the state of flux. The study also demonstrates that the singer of the past and the present praise singer have the same role and their chants or poetry or songs have the same effect. It also highlights situations where praises are chanted in modern times. These are graduation ceremonies, weddings, political gatherings and traditional ceremonies, for example, the annual rain making ceremonies. These events or occasions are inextricably linked to traditional praises. The study also highlights the fact that traditional praises present the history and heroic deeds of members of the clan to which the beneficiary belongs. They also express the deep feeling of royalty and loyalty. Like in the past they boost morale. / African Languages / M.A. (African Languages)