Les virophages sont des petits virus à ADN possédant une capside icosaédrique de 50-60 nm et un génome de 17 à 26 Kb codant potentiellement pour une vingtaine de gènes. Ils ont été découverts associés à des grands virus à ADN appartenant à l’ordre des Megavirales, pour lesquels leur présence serait délétère.Le premier projet du travail de thèse a été de faire le bilan des propriétés connues des virophages au travers d’une revue. La deuxième partie correspond à un bilan des avancées en matière d’isolement de virus géants dans les amibes – hôtes naturels des Mimiviridae –, pouvant être associés aux virophages. La troisième section se focalise sur la réplication des virophages Sputnik avec différents virus parmi les Mimiviridae, ainsi que sur l’isolement d’une nouvelle souche de Sputnik sans son hôte natif par l’utilisation d’un Mimiviridae en tant que virus rapporteur. La dernière partie est enfin basée sur l’identification d’un nouveau virophage – Zamilon – isolé en association avec un Mimiviridae du groupe C, et présentant une spécificité d'hôtes restreinte. Celle-ci est d'ailleurs étudiée.Les résultats présentés dans cette thèse démontrent une certaine complexité des interactions entre les virophages et leurs hôtes. Au sein d’une même famille d’hôtes, certains virophages possèdent un large spectre de spécificité, alors que d’autres ne peuvent se multiplier qu’avec certains d’entre eux, comme cela a déjà été observé chez les bactériophages. Compte-tenu de leur impact potentiel sur les virus géants, ces résultats soutiennent l’hypothèse d’une régulation des populations virales environnementales par les virophages. / Virophages are small DNA viruses with a 50-60 nm width icosahedral capsid encompassing a 17 to 26 Kb genome, putatively coding approximately 20 genes. They have been discovered in association with large DNA virus belonging to the order of the Megavirales, for which they are noxious.The first project of this thesis work was to recapitulate in a review the known features of the virophages. The second part corresponds to a summary of the advances in the field of giant viruses isolation in amoebas – the common hosts of Mimiviridae –. The third section is focused on the replication of the Sputnik virophages with viruses belonging to the Mimiviridae, and on the isolation of a new Sputnik strain with a Mimiviridae reporter instead of with its natural viral host. Finally, the last part is based on the identification of a new virophage – Zamilon – isolated in combination with a group C Mimiviridae, and exhibiting a restricted spectrum of specificity. The latter is herein studied.The results described herein show the complexity of the interactions between virophages and their giant hosts viruses. Within the same host family, some virophages have a broad-range host spectrum whereas others are limited to some viruses, a feature already described for bacteriophages. Regarding the potential impact of the virophages over their host viruses, these results support the hypothesis of a virophages’ major role in a regulation of viral populations in environment.

This thesis offers an insight in how information influence works in the digital modern age, through the use of strategic narratives in news reporting. The study uses a combination of a textual and narrative analysis in order to examine what kind of patterns are possible to distinguish in how the Russian state-funded news agencies RT and Sputnik are portraying Sweden in their reporting. Insights obtained by analyzing articles from the mentioned news outlets shows that four strategical ’master’-narratives can be found in the reporting: 1) Sweden is being ridiculed, 2) Sweden is portrayed as a collapsing state, 3) conspiracy theories about Sweden are made up and, 4) Russia is portrayed in friendly and peaceful terms. The analysis ultimately demonstrates how these four ‘master’-narratives can be understood as information produced in order to spread a negative image about Sweden and to promote a positive image of Russia. The study emphasizes the importance of continued research in the area and discusses the difficulties with addressing something that cannot be termed as fake news, but rather as fake narratives.

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The spins of planetary bodies are not stagnant; they evolve in response to both external and internal forces. One way a planet's spin can change is through true polar wander. True polar wander is the reorientation of a planetary body with respect to its angular momentum vector, and occurs when mass is redistributed within the body, changing its principal axes of inertia. True polar wander can literally reshape a world, and has important implications for a variety of processes—from the long-term stability of polar volatiles in the permanently shadowed regions of airless worlds like the Moon and Mercury, to the global tectonic patterns of icy worlds like Pluto. In this dissertation, we investigate three specific instances of planetary true polar wander, and their associated consequences. In Chapter 2 we investigate the classic problem of the Moon's dynamical figure. By considering the effects of a fossil figure supported by an elastic lithosphere, and the contribution of impact basins to the figure, we find that the lunar figure is consistent with the Moon's lithosphere freezing in when the Moon was much closer to the Earth, on a low eccentricity synchronous orbit. The South Pole-Aitken impact basin is the single largest perturbation to the Moon’s figure and resulted in tens of degrees of true polar wander after its formation. In Chapter 3 we continue our analyses of the lunar figure in light of the discovery of a lunar ”volatile" paleopole, preserved in the distribution of hydrogen near the Moon's poles. We find that the formation and evolution of the Procellarum KREEP Terrain significantly altered the Moon’s orientation, implying that some fraction of the Moon’s polar volatiles are ancient—predating the geologic activity within the Procellarum region. In Chapter 4 we investigate how the formation of the giant, basin-filling glacier, Sputnik Planitia reoriented Pluto. This reorientation is recorded in both the present- day location of Sputnik Planitia (near the Pluto-Charon tidal axis), and the tectonic record of Pluto. This reorientation likely reflects a coupling between Pluto’s volatile cycles and rotational dynamics, and may be active on other worlds with comparably large, mobile volatile reservoirs. Finally, in Chapter 5 we consider the broader context of these studies, and touch on future investigations of true polar wander on Mercury, Venus, Mars, Vesta, Ceres, and other worlds in our solar system.

On 4 October 1957, the Soviet Union launched Sputnik, the world's first artificial satellite, and the Space Age had arrived. While not an American achievement, Sputnik stands as a significant juncture in United States history. This thesis explores the resulting American political crisis, its development in the final three months of 1957, and the impact Sputnik had on American life. The thesis also examines the social and political context of the Sputnik crisis and will challenge some long-standing analysis of how America's reaction to the Soviet satellite developed. To accomplish this task, it was necessary to consult both primary and secondary sources. Important primary sources include government documents from both the Legislative and Executive Branches of the United States Government, attained from both printed volumes and online archives. The memoirs of key individuals also shed light on the mindset of prominent politicians and policymakers of the period. Newspapers and magazines from the era were examined to explore the media and public reaction to the Sputnik Crisis and related events. Secondary sources are used as both avenues of information and theory regarding the events, and also for the purposes of examining the consensus of others who have explored this topic. The topics covered in the thesis include the flow of events before, during, and after the Sputnik Crisis of 1957; analysis of contextual issues such as missile and satellite development and American culture of the period; and analysis of how the Sputnik Crisis unfolded and how this impacted American culture and national policy.

Les virus sont présents dans tous les écosystèmes, et sont les entités les plus abondantes dans le milieu marin. Bien que nous associons systématiquement virus aux maladies, la plupart d'entre eux coexistent cependant en équilibre avec leur hôte. Les virus sont associés à tous les règnes de la vie, même les virus qui affectent d'autres virus(virophages). La définition aujourd'hui d'un virus chez les virologues, c'est qu'un virus est un parasite génétique qui utilise des systèmes cellulaires pour sa propre réplication. Les hôtes les plus couramment utilisés par les virus que nous avons étudiés sont principalement des protozoaires. Ainsi, les Amoebozoa font l'objet de nombreuses études et sont utilisés pour isoler de nouvelles espèces intracellulaires( virus, bactéries). Ces espèces ont évolué de manière à résister aux effets consécutifs à la phagocytose ou à l'ingestion dans des vacuoles, et restent viable dans le cytoplasme de l'amibe, et ont le potentiel de se multiplier dans les parasites. Dans cette étude, nous avons dans un premier temps étudier les diverses interactions existantes entre virus Acanthamoeba polypaghaga Mimivirus(APMV) et des bactéries au sein de l'amibe. Pour cela, nous avons choisi un système original basé sur la co-culture de l'APMV, soit seul ou en combinaison avec deux autres microorganismes isolés individuellement à partir de l'amibe. Il s'agit d'une bactérie intracellulaire stricte(BABL1) et le virophage de APMV (Sputnik). Cela nous a permis de mettre en évidence, d'une part la capacité du virophage à moduler la virulence d'APMV tout en révélant, d'autre part, la bataille qui a eu lieu entre eux au cours de l'infection de l'hôte. dans un deuxième temps, nous avons examiné l'activité virucide des biocides couramment utilisés en pratique clinique pour la désinfection des équipements hospitaliers. APMV et Marseillevirus montrent une grande résitance aux biocides chimiques, en particulier l'alcool. Seule la température de 75°C et le glutaraldéhyde ont réussi à réduire les titres d'APMV et Marseillevirus à des niveaux indétectables. Après dessiccation ou exposition aux rayonnements ultraviolets, APMV et marseillevirus ont démontré leur stabilité durable. Précédent le pré-traitement des échantillons de l'environnement par l'éthanol à 70°C, a permis la disparition des contaminants bactériens sans réduire la charge virale, permettant leur isolement sur amibe, sans avoir besoin d'utiliser des antibiotiques, qui peuvent avoir un effet délétère su les amibes. / In this study, we first examined the various interactions taking place between the virus Acanthamoeba polyphaga Mimivirus (APMV) and bacteria within the amoeba. We chose an original system based on a co-culture of APMV either alone or in combination with two other organisms isolated from amoeba, i.e a strict intracellular bacterium (BABL1) and the virophage of APMV (Sputnik). This allowed us to highlight, on the one hand, the possibility to modulate the virulence of APMV while revealing, on the other hand, the battle which occurs between them during the infection of the host. We then examined the virucidal activity of biocides commonly used in clinical practice for the disinfection of hospital equipment. APMV and Marseillevirus show high resistance to chemical biocides, especially to alcohol. Only a temperature of 75°C or glutaraldehyde were able to reduce APMV and Marseillevirus titres to undetectable levels. Whether dried or under ultraviolet, APMV and Marseillevirus demonstrated their lasting stability. Previous pre-treatment of environmental samples by ethanol 70° allowed disappearance of bacterial contaminating bacteria without reducing giant virus load allowing their isolation on amoeba without need the use of antibiotic that may have a deleterious effect on amoebae.

The thesis aims to give a deeper understanding of the Russian use of soft power by examining identity building. This research is one of very few that shed light on Russia’s ambitions of exploitation of space. Further knowledge in the field is necessary to understand the underlying motives and objectives behind the Russian space program. This in-depth analysis fills a noteworthy knowledge gap. Using the method of narrative analysis as defined by Roselle, Miskimmon, and O’Laughlin (2014,2017), combined with the theory of strategic narratives and state identity as defined by Eriksson et al (2020), the thesis investigates Russian identity building, examining Russian space program under Putin. In particular, Putin’s 2013, 2016 and 2020 Cosmonautics Day video link-ups with the International Space Station are analyzed. This thesis attempts to define Russia’s future space plan and its geopolitical importance in maintaining the nation’s role on the international arena post-soviet. The results indicate that Eriksson et al's definition of cultural narratives about state identity can be found in future Russian space plans.

Thesis advisor: Seth Jacobs / The 1950s and early 1960s witnessed a dawning awareness throughout many sectors of American society that women were good for more than simply bearing children and tending house. The threat of communism, epitomized by the Soviet Union's launch of Sputnik in 1957, created extreme anxiety in the United States, an anxiety that manifested itself in two contradictory fashions. First, American women learned that the nation's best defense against communism began in the home, which was decidedly women's domain. The second message that American women received during this time is unquestionably the lesser known. The federal government and much of American society identified women as an untapped resource in national defense, a source of innovation and advancement in science and technology, thereby implying that with the help of American women, the United States could match Soviet achievements in these fields. / Thesis (BA) — Boston College, 2005. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: History. / Discipline: College Honors Program.

Information is power in the 21st century and strategic narratives through framing are nowadays regarded as part of the modern armoury of war. States constantly compete to create credible narratives in support of their actions on the international policy arena. After the Crimean crisis in 2014 the world was forced to open its eyes to medias new usage in modern warfare. State funded news agencies play an important role in this recent development and one of the most prominent actors is Russia. This thesis seeks to contribute to the discussion of strategic narratives and framing in the news media through a case study of the Russian news site Sputnik News. The thesis focuses on the news agency’s depiction of five empirical events in which the Swedish and Russian armed forces were involved during 2014 and 2015. A qualitative analysis of 25 news articles discussing the five events has detected proof of pro-Russian framing processes. The aim of Sputnik News seems to be a transformation of the general Swedish frame regarding Russia itself and perhaps more specifically Russia’s recent change in foreign policy.

ABSTRACT The aim for this study is to examine how relatives to children who participated/participate in Youth and family team Sputnik-group, oriented towards support groups for children of substance abusing parents, perceive the work done by the organization. On the basis of this aim three questions were formulated: do the relatives perceive a change in the communication with the child as an effect of the child’s participation in Sputnik’s activities, do the relatives perceive a change in their relationship with the child as an effect of the child’s participation in Sputnik’s activities, do the relatives think that their awareness of substance abuse have changed following the child’s participation in Sputnik’s activities. Previous research, Mead’s perspective, the concept of “groups” and support groups for children, were used to interpret the results. The method consists of a questionnaire which was sent out in 71 copies out of which 40 were returned. Further, staff members of Sputnik were interviewed to provide information about the program. The result of the questionnaire shows that some respondents perceived changes that consisted of an improved and more open communication and relation. Moreover, the majority of the respondents had a positive apprehension of the activity. Even among those who were more negative there was only one who was completely negative towards the whole program. The positive components described by the respondents correspond with the purpose of support groups for children as defined by the literature.