The Gaskiers glaciation (c. 580 Ma) has been classically traced along the Neoproterozoic Avalonian-Cadomian Terranes, which are now found scattered around the North Atlantic Ocean. Around 625 Ma these terranes were composed of volcanoes and arc-type basins. ‘Till-like’ diamictite horizons identified within these basins have been used as evidence for a ‘Snowball Earth-type’ glaciation at 580 Ma. However, others argue that these deposits are non-glacial debris flow deposits. To test the non-glacial interpretation of these deposits, a detailed sedimentological and basin analysis was conducted on the Neoproterozoic Squantum Member that occurs conformably with the volcanic-sedimentary rocks of the Boston Bay Group (eastern Massachusetts); this deposit is one of the most referenced ‘tillite’ deposits for the Gaskiers glaciation. This thesis shows that the ‘tillites’ of this succession are volcanically-influenced non-glacial debrites. Using the Lesser Antilles Arc and the adjacent Grenada Basin in the Caribbean Sea as a modern depositional analogue for the Avalonian-Cadomian Terranes, this study further reveals that debris flow facies types (diamicts) comparable to those of the Avalonian-Cadomian Terranes are produced at this modern arc and are recorded in the fill of the Grenada Basin. A similar study was conducted on the modern diamicts produced at the heavily glaciated Mount Rainier volcano (Washington, USA), revealing that despite the presence of local glaciers, debris flow is the dominant process depositing diamicts due to eruptions and flood events. The major thrust of this thesis is that it highlights the key role of tectonics and volcanism, not glaciation, in producing the diamictites of the Avalonian-Cadomian Terranes, and the importance of examining Neoproterozoic diamictite facies in their wider sedimentary, stratigraphic and tectonic context.

The Gaskiers glaciation (c. 580 Ma) has been classically traced along the Neoproterozoic Avalonian-Cadomian Terranes, which are now found scattered around the North Atlantic Ocean. Around 625 Ma these terranes were composed of volcanoes and arc-type basins. ‘Till-like’ diamictite horizons identified within these basins have been used as evidence for a ‘Snowball Earth-type’ glaciation at 580 Ma. However, others argue that these deposits are non-glacial debris flow deposits. To test the non-glacial interpretation of these deposits, a detailed sedimentological and basin analysis was conducted on the Neoproterozoic Squantum Member that occurs conformably with the volcanic-sedimentary rocks of the Boston Bay Group (eastern Massachusetts); this deposit is one of the most referenced ‘tillite’ deposits for the Gaskiers glaciation. This thesis shows that the ‘tillites’ of this succession are volcanically-influenced non-glacial debrites. Using the Lesser Antilles Arc and the adjacent Grenada Basin in the Caribbean Sea as a modern depositional analogue for the Avalonian-Cadomian Terranes, this study further reveals that debris flow facies types (diamicts) comparable to those of the Avalonian-Cadomian Terranes are produced at this modern arc and are recorded in the fill of the Grenada Basin. A similar study was conducted on the modern diamicts produced at the heavily glaciated Mount Rainier volcano (Washington, USA), revealing that despite the presence of local glaciers, debris flow is the dominant process depositing diamicts due to eruptions and flood events. The major thrust of this thesis is that it highlights the key role of tectonics and volcanism, not glaciation, in producing the diamictites of the Avalonian-Cadomian Terranes, and the importance of examining Neoproterozoic diamictite facies in their wider sedimentary, stratigraphic and tectonic context.

It has been commonly recognized that a series of global glaciation events occurred during the late Neoproterozoic Era (800 - 540 million years ago (Ma)). However, the extent of these glaciations continues to be hotly debated, namely whether the whole Earth was ice covered (ie. a “hard snowball”) or only the continents were fully ice covered but the oceans were not (“slushball/soft snowball”). Through a combination of climate modeling and carbon cycle modeling, I have investigated the plausibility of the “soft snowball” Earth hypothesis. It is demonstrated that the flow of land ice is critical to the formation of a “soft snowball”, such that low latitude land ice must be generated through ice transported from high latitudes. In order for a climate state of this kind to be realizable, continental fragments at low latitude must be well connected to those at high latitude, and the high latitude continents must be sufficiently extensive that a large ice sheet may initiate and subsequently flow to low latitude. It is found that these constraints are satisfied by the most accurate available continental reconstruction for both the initial Sturtian glaciation of the late Neoproterozoic and the subsequent Marinoan event. It is furthermore proposed that the alternative “hard snowball” hypothesis would have been prevented by a negative feedback due to the enhanced remineralization of dissolved organic carbon (DOC) in the ocean due to increased oxygen solubility in seawater at lower temperature. This process would release CO2 to the atmosphere, thus counteracting the initial climate cooling. I have also carried out detailed simulations in which an explicit model of the carbon cycle is coupled to the ice-sheet coupled climate model to investigate this feedback quantitatively. It is found that the remineralization of the DOC does indeed provide a strong negative feedback that counteracts climate cooling. The action of this feedback not only prevents the descent of the climate into a hard snowball state, but also enables the model to re-produce the δ13C carbon isotopic anomalies observed to accompany Neoproterozoic glacial events. The resistance of this carbon cycle coupled climate system to descent into a “hard snowball” state is further tested against stochastic perturbations, and shown to be robust in the presence of such influence.

It has been commonly recognized that a series of global glaciation events occurred during the late Neoproterozoic Era (800 - 540 million years ago (Ma)). However, the extent of these glaciations continues to be hotly debated, namely whether the whole Earth was ice covered (ie. a “hard snowball”) or only the continents were fully ice covered but the oceans were not (“slushball/soft snowball”). Through a combination of climate modeling and carbon cycle modeling, I have investigated the plausibility of the “soft snowball” Earth hypothesis. It is demonstrated that the flow of land ice is critical to the formation of a “soft snowball”, such that low latitude land ice must be generated through ice transported from high latitudes. In order for a climate state of this kind to be realizable, continental fragments at low latitude must be well connected to those at high latitude, and the high latitude continents must be sufficiently extensive that a large ice sheet may initiate and subsequently flow to low latitude. It is found that these constraints are satisfied by the most accurate available continental reconstruction for both the initial Sturtian glaciation of the late Neoproterozoic and the subsequent Marinoan event. It is furthermore proposed that the alternative “hard snowball” hypothesis would have been prevented by a negative feedback due to the enhanced remineralization of dissolved organic carbon (DOC) in the ocean due to increased oxygen solubility in seawater at lower temperature. This process would release CO2 to the atmosphere, thus counteracting the initial climate cooling. I have also carried out detailed simulations in which an explicit model of the carbon cycle is coupled to the ice-sheet coupled climate model to investigate this feedback quantitatively. It is found that the remineralization of the DOC does indeed provide a strong negative feedback that counteracts climate cooling. The action of this feedback not only prevents the descent of the climate into a hard snowball state, but also enables the model to re-produce the δ13C carbon isotopic anomalies observed to accompany Neoproterozoic glacial events. The resistance of this carbon cycle coupled climate system to descent into a “hard snowball” state is further tested against stochastic perturbations, and shown to be robust in the presence of such influence.

An interglacial mudstone sequence from the Port Askaig Tillite Formation on Islay was analysed using an Olympus XRF detector. The resulting geochemical log was compared with an XRF dataset acquired from a Quaternary sedimentary core from the Lomonosov Ridge in the Arctic Ocean. Chemical proxies representing climatic and environmental changes were analysed in an effort to specifically identify evidence of orbital forcing in the Cryogenian Period. The studied non-glacial rock-section from the Port Askaig Formation was interpreted as being deposited in a shallow marine setting at semitropical latitudes during an episode of global warming at some stage of the Sturtian glaciation (ca 717 – 660 Ma). The transport mechanism of glaciogenic material was by ice rafting. High hematite content was interpreted as an oxygenation event in a peritidal zone when isostatic rebound caused a sea level regression. Increasing amount of muscovite is interpreted to indicate increased weathering. Underlaying sequence of dolostone and overlaying sequence of sandstone were consistent with these interpretations. One interglacial phase is thus observed, which possibly could be attributed to Milankovitch orbital forcing. The interpretation of the paleoclimatic setting of the studied interglacial mudstone did not provide support for the Snowball Earth hypothesis in its “hard” version. Neither did other observations such as evidence of repeating glacial-interglacial cycles and banded iron formations (BIF) appearing also within the Sturtian glaciation.

This research is focused on strata deposited in northern Utah during the Cryogenian Period (850 – 635 Ma) of the Neoproterozoic Era, a period that derives its name from the widespread evidence for multiple, likely global, glacial events during this time, commonly referred to as “Snowball Earth” glaciations. This dissertation includes detailed studies of two Cryogenian successions in northern Utah that bracket potential “Snowball Earth” events: the upper part of the Uinta Mountain Group (deposited prior to the glaciations) and the dolomite member of the Kelly Canyon formation (hypothesized to have formed in the aftermath of a global glaciation that terminated at either 665 or 635 Ma). Both successions contain a lithostratigraphic, geochemical, and biotic record of the Earth’s oceans before and after the largest-magnitude glaciations in the history of our planet. The pre-glacial upper part of the Uinta Mountain Group in the area mapped for this study contains evidence of several (at least three) relatively short periods of ocean anoxia in which ferruginous conditions dominated and euxinia did not occur. There is no evidence that biota (organic-walled microfossil assemblages) were influenced by these brief anoxic events, but evidence from the composite Uinta Mountain Group stratigraphic record does suggest a gradual change in biota similar to that in the Chuar group. It is likely this biotic transition is related to nearshore eutrophication in the oceans, but additional redox geochemical information is needed to fully support this conclusion. The dolomite member of the Kelley Canyon Formation on Antelope Island (post-glacial component of this study) contains idiosyncratic lithologic features thought to be characteristic of 635 Ma deglacial strata, yet its C-isotope values do not lend unequivocal support to this global correlation, and regional correlations and U-Pb zircon ages suggest it is ~30 million years older. These results challenge the popular notion that Neoproterozoic post-glacial cap carbonates can be correlated based upon their lithologic “style,” and they also lend additional support to the possibility of a “Snowball Earth” event at ~665 Ma.

Video games and the social effects that they inflict upon society and the individual have been a highly debated subject. While studies have been made in regards to several social issues and their connection to video games, there was little research in regards to physical game gatherings like LAN-parties, as well as larger game gatherings like Dreamhack, and what the social effects of having physical contact with other people are at these gatherings. The goal with this study was to answer the question: “What are the social effects for the individual when participating in physical video game gatherings?”. This was done through a qualitative study by conducting five semi-structured interviews at the physical game gathering called Umeå Game Night that was located in the Umeå cultural center Klossen at Ålidhems Centrum. Four of the participants were male and one female. “Snowball-sampling” was used to gather the participants for the study through Game Night’s Facebook group. However, this sampling was unsuccessful when no participants were gained from it. Instead I had to take direct contact with people at the game gathering. The interviews were all done during the game gathering in their facility and were then transcribed for analysis with two types of methods; an inductive analysis that was backed up by a deductive analysis in the form of Activity Theory using Engeström’s model of Activity Theory. The results of this study showed that physical game gatherings helped to overcome some negative social effects that the participants thought surrounded online game as well as other social problems that they brought up during the interviews, like toxic behaviour, discrimination, and the feeling of not being welcome. There was an overwhelmingly positive reaction from the participants when being at the game gathering. Being able to socialize with other people proved to be the main motivation. However, even though physical game gatherings showed to improve negative social effects surrounding game, the learning process was still difficult to overcome for new players, and participating in these game gathering may even have negative results in keeping the new players interested in wanting to play as well as participate at the physical game gatherings. This was mainly because of the skill disparity between the experienced players, who were the majority at the game gathering, and the new players, who would feel potentially frustrated from seeing the experienced players being much better than themselves. However, the less experienced female participant in the study indicated that this issue may still be overcome, but more research needs to be done to see how big the issue surrounding the learning process when playing games at game gatherings actually is, and if there are ways to solve it.

The climate of the Neoproterozoic Snowball Earth is tested in the UKMO Unified Model, specifically the HadCM3 climate model. The model is largely left unchanged, but the boundary conditions, both external and initial, are adjusted to create experiments based on the Snowball Earth hypothesis. The model can reproduce multiple equilibrium climates, as have been seen in energy balance models of the Earth's climate. The modelled present day and Neoproterozoic versions of Earth can both reproduce both ice capped and ice covered climate states. Neither can reproduce a climate which remains ice free throughout the year, even with an equilibrated ocean or elevated levels of C02. In all cases the ice free climate reverts toward the ice capped climate after the first polar winter. The modelled Neoproterozoic ice covered climate, that is the climate of Snowball Earth, has a climate very different from the present day. These changes are mostly driven by the lower thermal inertia, latitudinal temperature differences and the changed meridional circulation that results. The weather of the modelled Snowball Earth climate is also very different, dom- inated by a strong diurnal variation due to solar heating, as opposed to the more varied weather in the present day. The model responds well to the conditions of the Snowball Earth climate, with temperatures similar to those predicted by a simple physical model. The model responds less well to high levels of C02 in the Snowball Earth climate. The ice model also allows excessive heat and moisture to escape from the ocean into the atmosphere compared to that that would be predicted from solid ice coverage of the ocean. The exit from a Snowball Earth state was also tested within the model. Neither an decrease in albedo nor an increase in CO2 is unable to increase the temperature of the climate system sufficiently to exit the Snowball Earth state.

« Les gens qui parlent ensemble votent ensemble ». En écrivant ces quelques mots, le sociologue britannique William Miller résumait, à la fin des années 1970, une tradition de recherche déjà ancienne : le vote, en tant qu‟expérience de groupe, se joue d‟abord dans les rapports que les citoyens ordinaires entretiennent avec ceux avec qui ils vivent quotidiennement. La recherche présentée dans cette thèse propose de réinterroger cette hypothèse par l‟intermédiaire d‟une enquête visant à saisir comment le contexte social d‟appartenance – entendu comme l‟entourage relationnel d‟un individu - structure la pratique des échanges politiques, et en quoi cette pratique peut-elle impacter les comportements électoraux individuels. L‟enquête en question a donc consisté à adapter la technique de l‟échantillonnage en boule-de-neige à la passation de questionnaires de personne à personne. Partant d‟un échantillon de base de dix personnes mobilisées à trois reprises – en 2009, 2010 et 2012 – il m‟a ainsi été possible d‟identifier des chaînes de relations grâce à la circulation de questionnaires au sein des cercles d‟interconnaissance des participants. En plus de données statistiques, l‟enquête s‟appuie sur une analyse ethnographique de la phase de construction des différents échantillons. Ce travail repose sur le postulat selon lequel les questionnaires élaborés constituent des "objets politiques", avec pour conséquence que les échanges de questionnaires au sein des populations étudiées instaurent de fait un cadre d'interactions présentant une dimension "politique". L‟étude ethnographique de la mise en oeuvre de cette passation offre ainsi l‟occasion de porter un regard original sur les moyens par lesquels des citoyens ordinaires organisent des échanges à dimension politique au sein de leurs réseaux d‟appartenance. Les résultats de cette analyse, confrontés à celle des échanges politiques plus ordinaires pratiqués au sein des contextes identifiés au cours de l‟enquête, montrent que le politique, loin d‟obéir à des logiques autonomes, prend sa source et prolonge les normes et les identités sociales produites par les groupes. La structure sociale du contexte – notamment son degré de cohésion – et sa composition en termes de ressources économiques, culturelles et politiques, déterminent le déroulement des échanges politiques et leur capacité à créer de la mobilisation et à faire en sorte que les identités collectives se traduisent en choix électoraux. / “People who talk together vote together”. By writing these few words, the British sociologist William Miller resumed, at the end of the 1970‟s, an old research tradition : voting, as a group experience, depends on the contacts that ordinary citizens maintain with those they live with everyday. The research presented in this thesis dissertation suggests questioning again this hypothesis by the mean of a survey that aims to understand how the social context of belonging – i.e. the relational surrounding of a person – shapes the practice of political exchange, and how this practice can affect individual electoral behavior. This survey consisted in an adaptation of the snowball sampling technique around the person-to-person transfer of questionnaires. Starting with a first sample of 10 people called up three times – in 2009, 2010, and 2012 – I could identify many chains of contacts by following the flow of questionnaires within circles of acquaintances of participants. Additionally with statistical data, the survey is based on an ethnographic analysis of the sampling procedure. This work is founded on the assumption that questionnaires elaborated for the survey constitute "political objects", with the consequence that the exchanges of questionnaires within the populations studied establish a setting of interactions with a political dimension. The ethnographic analysis of the elaboration of the transfer allows having an original look on the means by which ordinary citizens organize some political exchanges within the social networks they belong to. The results of this analysis, compared to the one of more ordinary exchanges practiced within social contexts identified during the survey, show that politics, far to respond to independent logics, take their origins in social norms and identities produced by groups. The social structure of context – mainly its cohesion degree – and its composition in terms of economic, cultural and political resources, determine the flow of political exchanges and their ability to create mobilization and to make possible the translation of collective identities into electoral choices.

Es evidente que la pobreza económica es uno de los problemas que presentan los países subdesarrollados, y que su reducción está relacionada con el aumento de la productividad en las PYME, dado el alto impacto que han representado a lo largo del tiempo. Muchas entidades han identificado la importancia de la agricultura en el sector económico del país. Por lo tanto, es necesario un diagnóstico en la zona. El propósito de este diagnóstico es tener una referencia del entorno desde el punto de vista general, en el que se pueden observar todas las interacciones, descripciones, particularidades y procesos existentes. En esta primera etapa del diagnóstico, se lleva a cabo utilizando un muestreo no probabilístico, que es un método común en la investigación. Uno de los muchos métodos utilizados para identificar el diagnóstico es el muestreo de bolas de nieve que permite encontrar el diagnóstico de poblaciones ocultas donde no hay manera de conocer todas las características de una población. La ventaja de utilizar este tipo de muestreo es que un solo informante inicial puede poner al investigador en contacto con otras fuentes. Además, sobre la base de los resultados obtenidos, se identificó que las causas del problema del sector de Chirimoya estaban asociadas a 3 procesos críticos que reflejaban la no productividad de este sector: proceso de gestión de planificación y control de la producción, proceso de gestión logística y proceso de gestión de la calidad. / It is evident that economic poverty is one of the problems presented by underdeveloped countries, and that their reduction is related to the increase in productivity in MSEs, given the high impact they have represented over time. Many entities have identified the importance of agriculture in the economic sector of the country. Therefore, a diagnosis is necessary in the area. The purpose of this diagnosis is to have a reference of the environment from the general point of view, in which all the interactions, descriptions, particularities and existing processes can be observed. In this first stage of the diagnosis, it is carried out using a non-probabilistic sampling, which is a common method in the investigation. One of the many methods used for identifying diagnosis is the snowball sampling that allows finding the diagnosis of hidden populations where there is no way to know all the characteristics of a population. The benefit of using this type of sampling is that a single initial informant can put the researcher in contact with other sources. Further, based on the results obtained, it was identified that the causes of the problem of the Cherimoya sector were associated to 3 critical processes that reflected the non-productivity of this sector: process of planning management and production control, process of logistic management and process of quality management. / Tesis