961 resultados para Booth, George G. (George Gough), 1864-1949


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Exiguobacterium antarcticum is a psychotropic bacterium isolated for the first time from microbial mats of Lake Fryxell in Antarctica. Many organisms of the genus Exiguobacterium are extremophiles and have properties of biotechnological interest, e. g., the capacity to adapt to cold, which make this genus a target for discovering new enzymes, such as lipases and proteases, in addition to improving our understanding of the mechanisms of adaptation and survival at low temperatures. This study presents the genome of E. antarcticum B7, isolated from a biofilm sample of Ginger Lake on King George Island, Antarctic peninsula.

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La Tesi di Dottorato prende in considerazione la collocazione storica e critica di G. E. Moore nel panorama filosofico europeo, con particolare riferimento al suo rapporto con il neo-hegelismo britanico prima e con il realismo poi. Al centro della Tesi si trova l'esame dell'intuizionismo etico di G. E. Moore.

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A comparative study was carried out on soils of the maritime (Arctowski, King George Island) and the continental (Casey, Wilkes Land) Antarctic. Soil sampIes are described for surface layers (0-10 cm) by their in situ temperature profiles as well as by field and laboratory analyses of grain sizes, pH and nutrient contents. Active cryoturbation is a main factor of mixing processes in surfaces with high silt and clay content. In both regions processes of podzolisation were recognized. Microclimatic conditions show the importance of small scale processes which are of special importance for freeze-thaw cycles. The distribution of nutrients and other inorganic components is rather homogeneous in regosols and leptosols. But in soils with organic top layers by lichen and moss cushions (crusts) accumulation occurs as well as displacement of metal ions into deeper layers (>10 cm). Histosols show patterns of brown soils. Special attention is given to the origin of nitrogen compounts and the different ways of import of other components (e.g. chloride) into the Antarctic system are discussed.

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The West Antarctic Peninsula is one of the fastest warming regions on the planet. Faster glacier retreat and related calving events lead to more frequent iceberg scouring, fresh water input and higher sediment loads which may affect benthic marine communities. On the other hand, the appearance of newly formed ice-free areas provides new substrates for colonization. Here we investigated the effect of these conditions on four benthic size classes (microbenthos, meiofauna and macrofauna) using Potter Cove (King George Island, West Antarctic Peninsula) as a case study. We identified three sites within the cove experiencing different levels of glacier retreat-related disturbance. Our results showed the existence of different communities at the same depth over a relatively small distance (about 1 km**2). This suggests glacial activity structures biotic communities over a relatively small spatial scale. In areas with frequent ice scouring and higher sediment accumulation rates, a patchy community, mainly dominated by macrobenthic scavengers (such as Barrukia cristata), vagile organisms, and younger individuals of sessile species (such as Yoldia eigthsi) was found. Meiofauna organisms such as cumaceans are found to be resistant to re-suspension and high sedimentation loads. The nematode genus Microlaimus was found to be successful in the newly exposed ice-free site, confirming its ability as a pioneering colonizer. In general, the different biological size classes appear to respond in different ways to the ongoing disturbances, suggesting that adaptation processes may be size related. Our results suggest that with continued deglaciation, more diverse but less patchy macrobenthic assemblages can become established due to less frequent ice scouring events.

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This study presents soil temperature and moisture regimes from March 2008 to January 2009 for two active layer monitoring (CALM-S) sites at King George Island, Maritime Antarctica. The monitoring sites were installed during the summer of 2008 and consist of thermistors (accuracy of ±0.2 °C), arranged vertically with probes at different depths and one soil moisture probe placed at the bottommost layer at each site (accuracy of ± 2.5%), recording data at hourly intervals in a high capacity datalogger. The active layer thermal regime in the studied period for both soils was typical of periglacial environments, with extreme variation in surface temperature during summer resulting in frequent freeze and thaw cycles. The great majority of the soil temperature readings during the eleven month period was close to 0 °C, resulting in low values of freezing and thawing degree days. Both soils have poor thermal apparent diffusivity but values were higher for the soil from Fildes Peninsula. The different moisture regimes for the studied soils were attributed to soil texture, with the coarser soil presenting much lower water content during all seasons. Differences in water and ice contents may explain the contrasting patterns of freezing of the studied soils, being two-sided for the coarser soil and one-sided for the loamy soil. The temperature profile of the studied soils during the eleven month period indicates that the active layer reached a maximum depth of approximately 92 cm at Potter and 89 cm at Fildes. Longer data sets are needed for more conclusive analysis on active layer behaviour in this part of Antarctica.

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Both the olivine-hearing tholeiite basalts of the island and the brown soils which have developed on the basalts contain 2-20% of a swelling clay mineral. It emerges from chemical, optical, X-ray diffraction and differential thermal analytical studies that this clay mineral is a Mg-rich, Fe2+ and AI-bearing tri-octahedral smectite, e. g. Mg-saponite. Due to petrographic and crystal chemical properties the saponite should have been formed by hydrothermal alteration of the primary Mg-Fe-minerals olivine and clinopyroxene. The soils consist of plagioclase, saponite and goethite which has been formed by chemical weathering within the soils. In the uppermost layer some of the soils contain humic substances and phosphatic material, the latter may be related to the recent production of guano.

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La tesis se centra en el estudio, descripción y análisis del libro publicado por el arquitecto británico George Edmund Street en 1865, bajo el título Some Account of Gothic Architecture in Spain. El libro dio a conocer una de la colecciones más importantes de dibujos realizada en el siglo XIX sobre la arquitectura ³tica española, y por lo tanto fue una primera referencia para su estudio, hasta bien entrado el siglo veinte. El volumen incluyó 107 grabados de diversos tipos de edificios con perspectivas y detalles, y 25 láminas con 45 planos de plantas de iglesias y claustros, muchos de ellos publicados por primera vez. Gracias a varias campañas de verano por la mitad norte del país, la casi inexplorada -desde un punto de vista académico- arquitectura española medieval fue finalmente descubierta. Este hecho conduce a una pregunta intrigante que está en el origen de esta investigación ¿cómo pudo Street en pocos viajes sentar las bases de la historia del ³tico español que hasta entonces los estudiosos españoles no habían sido capaces de definir? Esta tesis comienza describiendo la obra de Street en su contexto cultural con un breve repaso a su biografía y a su posición profesional y teórica. También su relación con las personas más representativas que participaron en el estudio de la arquitectura ³tica, como Robert Willis, William Whewell, Augustus Pugin, o George G. Scott. Se ha prestado especial atención, en explicar su papel relevante en el Gothic Revival, para entender el significado de su interés en la arquitectura ³tica continental. Estos capítulos preliminares son seguidos por una revisión del papel del dibujo como herramienta para la arquitectura de los viajeros en sus rutas en busca de la arquitectura ³tica. También se trata la influencia de la Royal Academy y sus académicos, (entre los cuales estuvo Street) y su formación académica. Finalmente la tesis entra en el estudio de los planos arquitectónicos que Street hizo durante sus viajes continentales de arquitectura, seguido por una descripción detallada de sus dibujos de España, analizando su método, su técnica, y las nuevas características aportadas, que fueron una novedad en el contexto español. También se lleva a cabo algunos estudios comparativos de los dibujos de España, gracias a una recopilación exhaustiva de bocetos y dibujos originales de Street, que en su gran mayoría se conservan en los archivos del RIBA, cotejándolos con sus versiones finales, con dibujos de la época de otros autores sobre los mismos edificios, y con fotos recientes. La tesis deja claro por qué y cómo Street, gracias a su soporte teórico y habilidades para el dibujo, pudo realizar algo que había pasado desapercibido para los estudiosos españoles de la época (construcción, historia de los estilos, señalamiento de períodos constructivos), lo que le permitió encontrar el lugar adecuado de la arquitectura ³tica española en la historia y en el mapa de la arquitectura ³tica europea. ABSTRACT This thesis focuses on the study, description and analysis of the book published by the British architect George Edmund Street in 1865, under the title Some Account of Gothic Architecture in Spain. The book displayed one of the most significant collections of drawings on Spanish Gothic Architecture made in the nineteenth century, and therefore was a first reference for its study, until well into the twentieth century. The book included 107 engravings, the surveying of various types of buildings with perspectives and details, and 25 sheets containing 45 ground plans of churches and cloisters, many of them new and published for the first time. Thanks to several summer campaigns in the north half of the country, the almost unexplored -from a scholar point of view- medieval Spanish architecture was eventually revealed. This fact lead to an intriguing question that is at the origin of this research: how could Street in a few trips lay the foundations of the history of Spanish Gothic that until then Spanish scholars had not been able to define? This thesis begins inscribing this Street's work in his cultural context. A brief review of his biography and professional and theoretical positions has been seen as necessary. Also his debts and relationship with the most representative people involved in the study of Gothic architecture, like Robert Willis, William Whewell, Augustus Pugin, or George G. Scott are discussed. Special attention has been paid, taken into account his relevant role in the Gothic Revival, to understand the significance of his interest in continental Gothic architecture. These preliminary chapters are followed by a review of role of drawing as a tool for Architectural travellers in their Tours in search of the Gothic architecture. The influence of the Royal Academy and its academicians, (among which was Street) and his educational background are here tackled. Eventually this thesis enters into the study of the architectural drawings Street made during his continental architectural journeys, which is followed by a detailed description and analysis of the Spanish ones: his methods, his technique, and the new features which were a novelty in the Spanish context are explored. Also in this thesis is carried out some comparative studies thanks to a previous exhaustive gathering of Street's sketches and original drawings, most of which are preserved in the RIBA archives. Their final versions, drawings of the same buildings from other contemporary draughtsman and pictures of their current state are compared with them. This thesis makes clear why and how Street thanks to his theoretical back-ground and portraying skills could realize what have passed unnoticed by contemporary Spanish scholars (construction, genealogy of forms, dating of periods) allowing him to find the proper place of the Spanish architecture in the history and the map of European Gothic architecture.