Les virus foamy simiens (VFS) sont la troisième famille des rétrovirus complexes exogènes infectant l'Homme. Ces virus, zoonotique, sont transmis par des fluides biologiques (principalement la salive), lors d'un contact direct entre un individu et un singe infecté. Ils établissent une infection chronique chez l'hôte infecté. À ce jour, aucune pathologie n'a été associée à au cas d'infections humaines par le VFS, et aucun cas de transmission secondaire n'a été rapporté dans la population. L'infection VFS représente un modèle naturel de la restriction de l'émergence d'un rétrovirus simien chez l'Homme. Lors de ma thèse, j'ai caractérisé la réponse humorale contre les VFS chez des personnes vivant au Cameroun ou au Gal infectées suite à des morsures lors d'épisodes de chasse. J'ai montré la présence d'anticorps neutralisants les VFS dans 48 sujets infectés, à des titres élevés. La population étudiée est infectée par des virus de deux génotypes qui diffèrent dans le domaine central de la protéine impliqué dans la liaison au récepteur cellulaire. J'ai montré des réponses neutralisantes spécifiques de chaque génotype des sujets étudiés et des réactivités croisées chez 40% d'entre-eux. Parmi ces derniers, la moitié est infectée par deux souches virales. En conclusion, mon travail de thèse est la première caractérisation des anticorps neutralisants chez des personnes infectées chroniquement par un VFS zoonotique : ces anticorps sont fréquemment détectés, à des titres élevés et sont dirigés contre des épitopes conservés entre les VFS de chimpanzé et de gorille. / Simian foamy virus (SFV) are the third family of exogenous complex retroviruses infecting humans. These viruses, of origins, are transmitted by body fluids (mainly saliva), through a direct contact between an individual and an infected m establish a chronic infection in the infected human host. To date, neither pathology, nor secondary transmission has be to be associated with SFV infection in humans. Therefore, SFV represents a natural model of restriction emerging simiar in humans. During my PhD, I characterized the humoral response against SFV in people living in Cameroon and Gabon, mainly infected bites during hunting episodes. I showed the presence of SFV neutralizing antibodies in the plasma of 48 infected individ titers. Our study population is infected with viruses of 2 different genotypes, which differ in the central region of the En region involved in binding to the cellular receptor.While in 60% of cases, neutralizing response was specific to a single genotype, 40% of cases showed cross-reactivity. Cr( was associated in 50% of cases with co-infection with viruses from both genotypes.In conclusion, my PhD is the first study to characterize neutralizing antibodies in individuals chronically infected with a zoonotic SFV : these antibodies are frequently detected at high titers and are directed against epitopes commonly found in chimpanzee and gorilla SFV.

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My thesis is on the epistemology of the sophist Protagoras. Through the reading of Plato' Theaetetus and Protagoras, I have reconstructed (a) Protagorean theory of knowledge, according to which Protagoras is an inter-subjectivist (as far as perceptions are concerned) and a moral relativist (as far as ethical judgements are concerned).In Chapter 1,1 first try to reconstruct the development of Protagoras' life. I list then Protagoras' few (extant) fragments, offering their different interpretations. Lastly, I deal with modern and most recent scholarship on Protagoras, ending the chapter with some considerations about the scholarly legitimacy of my thesis. In chapters 2 and 3, I deal with the Protagorean section in Plato's Theaetetus. Through a detailed (and critical) analysis of Plato's exegesis of Protagoras' maxim "Man is the measure of all things", I first reconstruct the perceptual (and individualistic) side of Protagoras' epistemology and then the ethical (and collective) side of such an epistemology. At the end of chapter 3, Protagoras' theory of knowledge already reveals itself as a rather complete epistemology. Such a (complete) picture of Protagoras' epistemology is reinforced in chapter 4, which deals with the Great Speech (mainly the myth) of the Protagoras. Through a close analysis of the core of the Great Speech, I confirm the ethical and collective reading of Protagoras' maxim that I have given in chapter 3. I end the chapter by providing some (modern) suggestions for taking Protagoras as a more serious epistemologist than he is actually thought of In the Conclusion, I sum up my whole reconstruction of the Platonic Protagoras and of his theory of knowledge, connecting it briefly with some features of fifth-century B.C Greek epistemology and, again, with some modern philosophical tenets.

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<p>In recent years, the number of vehicles has increased dramatically in Europe, USA and Japan. This causes a high traffic density and makes new security features a crucial point in order to keep the traffic safe. Inter-vehicle communication offers solutions in this field, as cars can communicate with each other. To this date, there is no special technology standardized for inter-vehicle communication. This is the reason why car makers, researchers and academics have invested money and time in different research projects so that in future they may come up with a common solution. Some of the technologies like DSRC, CALM, IEEE 802.11 or Infrared are thought to be more reliable than others according to different authors [9][23].</p><p>The technologies described above will help to improve road safety and application scenarios like lane change, blind merge or pre and post crash situations can be addressed. The position of each car is known through a GPS; speed, heading and other dynamic data of a car are known to all cars in the same vicinity.</p><p>In this thesis, a thorough investigation of services and applications related to inter-vehicular communication technology (i.e. car-to-car and car-to-infrastructure or vice versa) will be carry out. The emphasis will be on requirements on the communication system, sensors and user interface in order to make the technology more useful for future vehicle alert system and to avoid as many of the mentioned scenarios as possible. A rear-end collision can be avoided if the driver is warned within 0 to 5 second of potential accident.</p>

In recent years, the number of vehicles has increased dramatically in Europe, USA and Japan. This causes a high traffic density and makes new security features a crucial point in order to keep the traffic safe. Inter-vehicle communication offers solutions in this field, as cars can communicate with each other. To this date, there is no special technology standardized for inter-vehicle communication. This is the reason why car makers, researchers and academics have invested money and time in different research projects so that in future they may come up with a common solution. Some of the technologies like DSRC, CALM, IEEE 802.11 or Infrared are thought to be more reliable than others according to different authors [9][23]. The technologies described above will help to improve road safety and application scenarios like lane change, blind merge or pre and post crash situations can be addressed. The position of each car is known through a GPS; speed, heading and other dynamic data of a car are known to all cars in the same vicinity. In this thesis, a thorough investigation of services and applications related to inter-vehicular communication technology (i.e. car-to-car and car-to-infrastructure or vice versa) will be carry out. The emphasis will be on requirements on the communication system, sensors and user interface in order to make the technology more useful for future vehicle alert system and to avoid as many of the mentioned scenarios as possible. A rear-end collision can be avoided if the driver is warned within 0 to 5 second of potential accident.

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