Cell proliferation and differentiation are tightly regulated processes required for the proper development of multi-cellular organisms. To understand the effects of cell proliferation on embryo patterning in mice, we inactivated Aurora A, a gene essential for completion of the cell cycle. We discovered that inhibiting cell proliferation leads to different outcomes depending on the tissue affected. If the epiblast, the embryonic component, is compromised, it leads to gastrulation failure. However, when Aurora A is inactivated in extra-embryonic tissues, mutant embryos fail to properly establish the anteroposterior axis. Ablation of Aurora A in the epiblast eventually leads to abnormal embryos composed solely of extra-embryonic tissues. We took advantage of this phenomenon to generate embryonic stem (ES) cell-derived mice. We successfully generated newborn pups using this epiblast ablation chimera strategy. Our results highlight the importance of coordinated cell proliferation events in embryo patterning. In addition, epiblast ablation chimeras provide a novel in vivo assay for pluripotency that is simpler and more amenable to use by stem cell researchers.

The Auroral Acceleration Region (AAR) is a key region in understanding the interactionbetween the Magnetosphere and Ionosphere. To understand the physical, spatial, and temporal features of the region, multi-point measurements are required. Distributed small-satellite missions such as constellations of multiple nano satellites (for example multi-unit CubeSats) would enable such type of measurements. The capabilities of such a mission will highly depend on the number of satellites - one reason that makes low-cost platforms like CubeSats a very promising choice. In a previous study, the state-of-the-art of miniaturized payloads for AAR measurements was analyzed and evaluated on the capabilities of different multi-CubeSat configurations equipped with such payloads in addressing different open questions in AAR. This thesis will provide the mission analysis of such a multi-CubeSat mission to the AAR and possible mission design. This includes defining the mission scenario and associated requirements, developing a mathematical description of AAR that allows for specific regions in space to be targeted, an optimisation process for designing orbits targeting these regions, conversion of a satellite formation to appropriate orbits, verifying the scientific performance of this formation and the various costs associated with entering, maintaining, and exiting these orbits.

No description available.

The Aurora zone is an ore zone which was recently discovered in the Björkdal gold mine, northern Sweden, and it has been the main focus of mining and exploration activities for the past few years (Pressacco et al., 2020). The purpose of this project is to determine how gold occurs in the Aurora zone. A three-day long campaign was therefore done at the processing plant at the Björkdal mine where 11 000 tonnes of ore from the drive Aurora 370/1650 E+W were processed. The issue regarding the ore from the Aurora zone is that it has a lower recovery compared to the rest of the mine.  Six chip samples, 12 samples from the ingoing plant feed and two tailing samples were analyzed using optical microscopy, scanning electron microscopy (SEM), and automated mineralogy (QEMSCAN). This was done to determine the mineralogy, grain size distribution, mineral associations, textures and modal mineralogy which all are factors that could influence the metal recovery at the processing plant. The samples were prepared using the cold mounting method and epoxy mounts were created. After cutting, grinding, and polishing, the sections were ready to be examined. Optical microscopy was performed using a Nikon ECLIPSE E600 POL microscope. Ten epoxy mounts were carbon coated and automated mineralogy was performed on nine of them in a ZEISS Sigma 300 VP using a recipe (analysis mode) for “bright phase search”. Manual point-ID analysis was done using a ZEISS MERLIN SEM. Fifty gold grains were identified in this study, 48 of them in the chip samples and two of them in the ingoing-feed samples. 64% of them were associated with silicates, 22% were quartz associated, 12% were associated with bismuth minerals and 2% of them were associated with sulfides. The grain size distribution has a range between 0.7 and 19 μm and the median grain size is 4.8 μm. The gold grains identified from the Aurora zone have a significantly smaller median grain size than gold from other parts of the mine. The majority of the gold grains identified in this study, have a very fine grain size, are mainly associated with silicates and most prominently occur as inclusions. Gold that occurs in this way is typically difficult to recover in the processing plant and it seems like this is the main reason for the lower gold recovery from the Aurora ore zone.  No gold was found in the tailings, suggesting that the mineral process is performing well although no thorough conclusion can be made in regards of the processing. The lack of data for the different sample types in this project is an issue. Gold from the tailings must be identified and examined to draw any clear conclusions regarding the processing. For future work, it is therefore recommended to analyze more tailing samples and to implement hydroseparation at the sample preparation stage, to separate the heavier gold particles from lighter minerals. Then more gold will most likely get detected in the tailing samples.

Joaquín Salvador Lavado Tejón, el famoso humorista gráfico conocido mundialmente como Quino, en una de sus tiras del 29 de julio de 2002 grafica una situación singular. A partir de cuatro viñetas ilustra la condición histórica de servidumbre que ha subsumido a la mujer desde la época más tradicional hasta la contemporánea. En la última viñeta, Mafalda concluye con la siguiente reflexión: ―Claro, lo malo es que la mujer en vez de jugar un papel, ha jugado un trapo en la historia de la humanidad‖ (Quino 2002). Emprendí el análisis de La sangre de la aurora por dos razones que están íntimamente ligadas a esta última sentencia de Quino: el papel de la mujer a lo largo de los diferentes procesos históricos y la función de ―trapo‖ que el sistema patriarcal le ha impuesto. / Tesis

El debate sobre la violencia y las víctimas ha cobrado mayor protagonismo en los últimos años, así como la producción cultural que se hace alrededor de esta categoría. Pero esta centralidad de la víctima se ha vuelto problemática, como ya lo han señalado otros estudios, en cuanto encasilla a los sujetos en roles pasivos o los inserta como meros objetos. Es por esta razón que me ha interesado analizar la novela La sangre de la aurora, pues si bien mantiene a la víctima como una categoría central y remanente de la violencia, su visión va más allá de ella y no permite limitarla a un estereotipo determinado. Considero que esta tesis rescata esos elementos que la novela de Salazar Jiménez visibiliza sobre la violencia y los tipos de violencia que sufren las víctimas y cómo se diferencia de otras narrativas al representarla, dándole una nueva configuración al término. Asimismo con la ayuda de la teoría psiconalítica determino que la novela ahonda en el pasado traumático de las víctimas y construye una noción de trauma que se ve reflejado en la forma narrativa fragmentada y caótica. Todo ello, dentro de una perspectiva de género que nos revela una potencialidad de lo femenino. De este modo, la novela va más allá de las víctimas al devolverles a éstas su condición de sujetos políticos, otorgándoles una voz y agencia propias, recogiendo todas sus complejidades y experiencias y, además, problematizando el término al incluir al perpetrador en dicha categoría. / Tesis

Literary descriptions of shifting from and transgressing assigned sex were common in 19th Century Sweden. This thesis forms a contribution to the larger project of writing a history of Swedish trans literature, and develops new interpretations of certain works of fiction by applying a transgender studies perspective. Through trans readings the thesis also examines what potential and possible implications literature might have for trans people beyond the literary realm. Trans readings are able to supplement earlier research by providing a nuanced understanding of the production of trans- and cisgenders. The theoretical perspectives used in the thesis are drawn for the most part from queer and transgender studies. The thesis adopts a conceptual understanding of trans as a movement, and aims to widen the scope of what may be considered relevant to a history of trans literature. The primary objects of analysis are the 1833 autobiography of widely known thief and cross-dresser Lasse-Maja (Lars Molin), C.J.L. Almqvist’s Drottningens juvelsmycke (1834), and Aurora Ljungstedt’s Moderna typer (1874). In closing, two texts from the fin-de-siècle are also closely read; Amanda Kerfstedt’s Reflexer (1901) and Frida Stéenhoff’s “Ett sällsamt öde” (1911). A wide range of other fiction is additionally studied in order to establish a contextual pattern of trans literary traditions. The thesis demonstrates that trans permeates all kinds of fiction, and that the characters analysed construct both trans and cis gender categories. It concludes that trans is done in a variety of ways, and with a variety of meanings in 19th and early 20th century literature. Trans is often depicted as a positive, fruitful and desirable act, through trans characters who are both themselves subjects of erotic desire and who become symbols of liberty and emancipation. Other trans figures however are often counter images of what are considered to be correct sexes, and are depicted as threatening and/or ridiculous. Both these negative and positive representations of trans affirm the gender binary. At the same time, they also break and destabilize that same binary, and the trans characters in the study both can and cannot be interpreted as transgressing cis- and heteronormativity respectively.

The Auroral Large Imaging System (ALIS) was proposed in 1989 by Åke Steen as a joint Scandinavian ground-based nework of automated auroral imaging stations. The primary scientic objective was in the field of auroral physics, but it was soon realised that ALIS could be used in other fields, for example, studies of Polar Stratospheric Clouds (PSC), meteors, as well as other atmospheric phenomena. This report describes the design, operation and scientic results from a Swedish prototype of ALIS consisting of six unmanned remote-controlled stations located in a grid of about 50 km in northern Sweden. Each station is equipped with a sensitive high-resolution (1024 x 1024 pixels) unintensified monochromatic CCDimager. A six-position filter-wheel for narrow-band interference filters facilitates absolute spectroscopic measurements of, for example, auroral and airglow emissions. Overlapping fields-of-view resulting from the station baseline of about 50 km combined with the station field-of-view of 50° to 60°, enable triangulation as well as tomographic methods to be employed for obtaining altitude information of the observed phenomena. ALIS was probably one of the first instruments to take advantage of unintensi- fied (i.e. no image-intensifier) scientific-grade CCDs as detectors for spectroscopic imaging studies with multiple stations of faint phenomena such as aurora, airglow, etc. This makes absolute calibration a task that is as important as it is dificult. Although ALIS was primarily designed for auroral studies, the majority of the scientific results so far have, quite unexpectedly, been obtained from observations of HF pump-enhanced airglow (recently renamed Radio-Induced Aurora). ALIS made the first unambiguous observation of this phenomena at high-latitudes and the first tomography-like inversion of height profiles of the airglow regions. The scientific results so far include tomographic estimates of the auroral electron spectra, coordinated observations with satellite and radar, as well as studies of polar stratospheric clouds. An ALIS imager also participated in a joint project that produced the first ground-based daytime auroral images. Recently ALIS made spectroscopic observations of a Leonid meteor-trail and preliminary analysis indicates the possible detection of water in the Leonid.

AtMAP65-4 est une protéine associée aux microtubules appartenant à la famille des AtMAP65s qui compte 9 membres identifiés chez Arabidopsis thaliana. Ces protéines appartiennent à une famille conservée au cours de l'évolution, les MAP65s. Ainsi, des protéines homologues sont présentes chez de mammifères (PRC1), chez la levure (Ase1p) ou chez la drosophile (FEO). Jusqu'ici l'étude des propriétés moléculaires et fonctionnelles des AtMAP65s s'est portée essentiellement sur l'étude d'AtMAP65-1 et AtMAP65-5. La principale caractéristique de ces protéines est d'induire la formation de faisceaux de microtubules in vitro. La distribution des AtMAP65s in vivo est très régulée, celle-ci sont localisées avec des réseaux des microtubules bien définis. Ainsi, leur rôle supposé est de mettre en place ces réseaux puis de participer à leur maintient. La localisation d'AtMAP65-4 apparait comme très intéressante car elle est strictement associée avec les microtubules du fuseau mitotique. D'après les résultats obtenus au cours de ce travail, nous avons suggéré que la fonction in vivo d'AtMAP65-4 est de participer à la mise en place et au maintient des microtubules en faisceaux dans les fibres kinétochoriennes lors de la division cellulaire. Lors d'une étude in vitro nous avons montré qu'AtMAP65-4 modifie les paramètres dynamiques de polymérisation des microtubules. Outre sa capacité à former des faisceaux, AtMAP65-4 permet une croissance régulière des microtubules au sein des faisceaux qu'elle induit. Le mécanisme d'action de la MAP à l'échelle moléculaire a été analysé à travers une étude bioinformatique où nous avons modélisé l'activité d'AtMAP65-4. Les données obtenues montrent qu'AtMAP65-4 peut bloquer les évènements de dépolymérisation des microtubules. Par ailleurs, l'activité d'AtMAP65-4 pourrait être régulée in vivo par des modifications post traductionnelles. En effet, nous avons montré et étudié l'effet de la phosphorylation d'AtMAP65-4 par les kinases Auroras. Cette phosphorylation pourrait être impliquée dans la régulation de l'activité d'AtMAP65-4 au cours de la mitose. / AtMAP65-4 is a microtubule-associated protein belonging to the AtMAP65s family that comprises 9 members identified in Arabidopsis thaliana. These proteins belong to a family conserved during evolution, MAP65s. Thus, homologous proteins are present in mammals (PRC1), in yeast (Ase1p) or Drosophila (FEO). So far the study of molecular properties and functional AtMAP65s has focused mainly on AtMAP65-1 and AtMAP65-5. The main feature of these proteins is to induce the formation of microtubule bundles in vitro. In vivo, these AtMAP65s are localized with subsets of microtubule bundles as they are suggested to play a role in establishing and maintaining these networks. From the results we obtained on AtMAP65-4 properties during this work such as the in vivo localization, biochemical properties and functional effetc on the MT polymerization, we suggested that the in vivo function of AtMAP65-4 is involved in setting up and maintaining microtubule bundles within kinetochore fibers during cell division. In vitro studies allowed us to show that AtMAP65-4 changes the dynamic parameters of microtubule. In addition to its ability to form bundles, AtMAP65-4 allows steady growth of microtubules in bundles it induces. The mechanism of action of the MAP at the molecular level was analyzed through a bioinformatics study where we modeled the activity of AtMAP65-4 and concluded that it could block the depolymerization events. Moreover, the activity of AtMAP65-4 could be regulated in vivo by post-translational modifications. Indeed, we have shown that AtMAP65-4 is phosphorylated by Aurora kinases in vitro. The effect of this phosphorylation during mitosis is under investigation.

Thesis (M.F.A.)--Boston University PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / The purpose of this thesis is to closely analyze some of the individual authorial voices that have emerged from contemporary Romanian cinema. Billed by the international critical establishment as a "New Wave," the recent slate of Romanian productions, while very successful on the international festival circuit, still lacks an apt conceptualization of the precise characteristics that set these new filmmakers apart, not only from other international directors, but also from one another. The analysis focuses on six recent productions: Stuffand Dough (2001), The Death of Mr. Lazarescu (2005) and Aurora (2010) by Cristi Puiu, 12:08 East of Bucharest (2006) and Police, Adjective (2010) by Corneliu Porumboiu, and The Autobiography of Nicolae Ceausescu (2010) by Andrei Ujica, breaking down the individual authorial characteristics and thematic and stylistic concerns of each filmmaker and contextualizing them within the larger history of Romanian film, as well as the trajectories of international art cinema.