664 research outputs found
A TALE OF TWO CITIES: DIET, HEALTH AND MIGRATION IN POST-MEDIEVAL COVENTRY AND CHELSEA THROUGH BIOGRAPHICAL RECONSTRUCTION, OSTEOARCHAEOLOGY AND ISOTOPE BIOGEOCHEMISTRY
Get PDFBiogeochemical research has over the past four-and-a-half decades improved our understanding of human interaction with past environments. The application of different isotope systems has allowed archaeologists to interpret ancient diet, migration and pollution. Although well established in archaeology, biogeochemical interpretations are burdened with questions not only as to the methodology employed but also whether the data presents a consistent picture of past human activity. The use of biographically identifiable individuals offers a means by which the isotope systems may be tested against extent documentary evidence. A sample of forty-five individuals, almost half of which were named individuals, were obtained from the sites of Holy Trinity (Coventry) and St. Luke's (Old Street, Chelsea) and the stable isotopes of carbon, nitrogen, oxygen, strontium and lead analysed. The biographies ofthe named individuals were reconstructed through analysis ofextant historical documentation and' used to provide a framework of interpretation for the biogeochemical teclmiques applied. Comparisons are made between the two sites in relation to the biogeochemical techniques employed, biographical reconstruction and osteoarchaeological evidence for disease, migration and diet to address methodological issues and broader questions on 'i,ndustrialisation' during the eighteenth and nineteenth centuries. The osteoarchaeological evidence suggests separation of the two groups into discrete' populations, one that is characterised by occupationally-derived osteoarthropathies (Coventry), and the second, Chelsea, which has an absence of these pathologies. This supports the historical character of the t\VO cities: Coventry as an industrial city in contrast to Chelsea, a 'village of palaces' or pleasure resort. Biogeochemically, carbon and nitrogen isotopes revealed a picture of status-based access to protein resources in a diet that is particularly dominated by freshwater fish, terrestrial omnivores such as pig, or a combination of the two. There is, however, little evidence for a difference in access to such resources between the sexes. Likewise, strontium and oxygen isotopes are capable of differentiating between the two populations and therefore in identifying local and migrant individuals, though limitations in the sample prevent the full utilisation of this data. In one case (Milborough Maxwell) the isotopic techniques \vere able to reveal trans-Atlantic migration between England and the Caribbean. Analysis of lead isotopes of the two populations indicates that while there is little to differentiate the two sites, heavy metal exposure is greater for the eighteenth and nineteenth centuries than for previous periods.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Molecular gas in dusty high-redshift galaxies
No full textWe present high-resolution observations of carbon monoxide (CO) emission lines for three high-redshift galaxies in order to determine their molecular gas and star formation properties. These galaxies (SMM J14011+0252, SMM J00266+1708, and SDSS J0901+1814) have large infrared luminosities, which imply high dust enshrouded star formation rates and substantial molecular gas masses. We observed these sources using the Robert C. Byrd Green Bank Telescope, the Karl G. Jansky Very Large Array, the Plateau de Bure Interferometer, and the Submillimeter Array in order to obtain measurements of multiple CO spectral lines, allowing us to determine the physical conditions of the molecular gas. Our high resolution and multi-line CO mapping of SMM J00266+1708 reveals that it is a pair of merging galaxies, whose two components have different gas excitation conditions and different gas kinematics. For SMM J14011+0252 (J14011), we find a near-unity CO(3-2)/CO(1-0) intensity ratio, consistent with a single phase (i.e., a single temperature and density) of molecular gas and different from the average population value for dusty galaxies selected at submillimeter wavelengths. Our radiative transfer modeling (using the large velocity gradient approximation) indicates that converting the CO line luminosity to molecular gas mass requires a Galactic (disk-like) scale factor rather than the typical conversion factor assumed for starbursts. Despite this choice of conversion factor, J14011 falls in the same region of star formation rate surface density and gas mass surface density (the Schmidt-Kennicutt relation) as other starburst galaxies. SDSS J0901+1814 (J0901) was initially selected as a star-forming galaxy at ultraviolet wavelengths, but also has a large infrared luminosity. We use the magnification provided by the strong gravitational lensing affecting this system to examine the spatial variation of the CO excitation within J0901. We find that the CO(3-2)/CO(1-0) line ratio is higher in central regions than in extended structure, supporting a picture of the molecular gas where regions of higher excitation gas (higher temperature and density) are embedded in an extended low excitation phase. We also examine the resolved Schmidt-Kennicutt relation as a function of CO line excitation for J0901 and find no systematic difference between the best-fit power law indices for the two emission lines.Ph. D.Includes bibliographical referencesby Chelsea Electra Sharo
A 'philosophical storehouse': the life and afterlife of the Royal Society's repository
No full textPhDIn June 1781, the Royal Society’s repository was transferred to the British
Museum. Though ostensibly as a result of the limited space in the Royal Society’s
purpose-built accommodation at Somerset House, the Society were perhaps also a
little relieved to relinquish a collection that had proved to be somewhat burdensome
during its residence at the Society and which was frequently criticised for its decaying
specimens, broken items and missing, possibly stolen, objects. However this seems to
be only part of the story. Drawing upon manuscript material in the Royal Society and
the British Library, this study will examine the repository’s pattern of usage,
collecting strategies and intellectual output throughout its life, in addition to exploring
its afterlife at the British Museum using the British Museum’s, Royal College of
Surgeon’s and Natural History Museum’s extensive archives. This thesis will seek to
reveal an alternative account of the Royal Society’s repository arguing that it was
comprised of a substantial and significant collection that the British Museum, at least
initially, appears to have been grateful to receive and which, periodically, played a
central role in the Society’s and naturalists' work
A politics of conversion: nihilism and love in Toni Morrison's fiction
Get PDFTese (doutorado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão. Programa de Pós-Graduação em Letras.O estudo Uma Política de Conversão: Niilismo e Amor na Ficção de Toni Morrison começa com a idéia de que a Literatura Afro-Americana apresenta um sentido de auto-reflexividade e hibridismo, através do qual autobiografia dialoga com romance, o espiritual se funde com o político. A partir deste traço dialógico a auto-reflexividade é politicamente estabelecida entre niilismo e amor. Na política de conversão, o estudo analisa as formas como mulheres negras, individualmente ou em grupo, fogem da escravidão para a liberdade, avançam da individualidade para a coletividade, ou substituem niilismo por amor. Metodologicamente o estudo apresenta sete capítulos. O primeiro discute os aspectos dialógicos que ilustram as conexões entre narrativas espirituais, de escravos e ficção, entre espiritualidade e política. O segundo examina o diálogo entre a conversão, pregação pública e formação da comunidade em Diário e Experiências Religiosas de Lee. O capítulo sugere que ao afirmar espiritualidade e humanidade a narradora abre profundo espaço para a mulher negra reclamar direitos civis. O terceiro discute o diálogo no interior da política de conversão entre narrativa de escravos e ficção. Este diálogo lida com niilismo e amor em Incidentes de Jacobs e Amada, Sula e O Olho Mais Azul de Morrison. Para a análise de niilismo e amor valores individuais e coletivos são considerados em relação a cinco aspectos: ambiente e agente antagonistas, agente de apoio, propósito da personagem e resultado alcançado. É visível, no estudo, o apoio que certas mulheres recebem de suas comunidades para contra-atacar antagonistas. O apoio nem sempre resulta na superação do niilismo e, por isso, derrota temporária pode ocorrer antes que elas sejam reintegradas à comunidade, como acontece com Linda Brent. O quarto capítulo examina as fraquezas e as energias da política da conversão e a reintegração de Sethe Suggs à comunidade de Bluestone Road. O quinto avalia como a comunidade de Bottom tenta controlar a individualidade de Sula Peace e como um grupo de mulheres lideradas por Nel Wrights consegue resgatar o espírito de independência da heroína. O sexto mostra como a política da conversão das mulheres de Lorain é incapaz de garantir a saúde mental de Pecola Breedlove, mas consegue criar um papel mais consistente para o grupo. No sétimo, a conclusão examina da relação dialética entre niilismo e amor ou auto-amor nas experiências dos indivíduos e dos grupos. O estudo sugere que em Incidentes a busca de Linda Brent por liberdade envolve elementos de autodestruição e de autoempoderamento. Da mesma maneira, o estudo conclui que em Amada o amor que Sethe Suggs tem para as suas crianças mata a própria filha, enfatizando, assim, o desejo de livrá-la da escravidão. Igualmente em Sula, a individualidade de Sula Peace não apenas limita, mas também expande as experiências do grupo, levando-o à emancipação. Finalmente, em O Olho Mais Azul a luta de Pecola Breedlove por amor e beleza reflete auto-ódio ao mesmo tempo em que reconstrói a auto-apreciação de toda a comunidade
Groups with the basis property
No full text"The first author is supported by an EPSRC Doctoral Training Grant"We study finite groups for which every minimal generating set has the same cardinality. A group has the basis property if it and every subgroup satisfies this condition on minimal generating sets. We classify all finite groups with the basis property.Peer reviewe
Species turnover and invasion of dominant freshwater invertebrates alter biodiversity–ecosystem-function relationship
Get PDFFreshwater ecosystems rely on allochthonous resources. Integration of these subsidies depends on diversity of both terrestrial resources and aquatic shredder and decomposer communities, but the diversity effects on leaf litter breakdown and decomposition are less clear in aquatic than terrestrial ecosystems. We need a better understanding of this relationship because aquatic communities are rapidly changing with species invasions and anthropogenic impacts. Here, we experimentally disentangled the effects of leaf and shredder richness on leaf litter breakdown by macroinvertebrates in mesocosm experiments using three species of amphipods, a dominant guild of crustaceans in European freshwater ecosystems. Increased leaf richness led to lower-than-predicted leaf consumption by native shredders, with mixed evidence of resource-switching or prioritization of preferred food items within a leaf mix. Higher shredder species richness never promoted leaf consumption rates compared to predictions from relevant single-species experiments, and instead sometimes substantially decreased leaf consumption. We then conducted a meta-analysis of leaf litter consumption rates by seven widely distributed amphipod species (the three used in the experiments and four additional species). As expected based on our own experiments, nonnative amphipod species generally had lower biomass- adjusted leaf litter consumption rates, although their larger body size led to higher per-individual leaf consumption rates. Contamination of the water by metals, pesticides, and other chemicals additionally significantly decreased leaf litter consumption by multiple native and nonnative species compared to unpolluted systems. While the meta-analysis suggested that litter consumption, and thus breakdown, would decline if native shredders are replaced by nonnative heterospecifics, complete species replacement is not the only outcome following immigration in a meta-community context. Our experiments suggest that breakdown rates could remain reasonably high where native species coexist with nonnative arrivals. Experiments that neglect the ecological realism of species coexistence will necessarily mischaracterize effects on ecosystem functioning
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