Uranium-series radionuclide records of paleoceanographic and sedimentary changes in the Arctic Ocean

Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution February 2009.The radionuclides 231Pa and 230Th, produced in the water column and removed from the ocean by particle scavenging and burial in sediments, offer a means for paleoceanographers to examine past dynamics of both water column and sedimentary processes. I show for the first time that a state of balance exists between 230Th production and burial in the Central Arctic basins, based on measured sedimentary 230Thxs inventories in box cores, establishing this nuclide’s utility as a paleoceanographic indicator of sedimentary processes and as a normalization tool. I present the first 230Th-normalized particle fluxes calculated for the central Arctic: vertical particle fluxes were extremely low during the late glacial, rose during the deglaciation due to particle inputs from shelf inundation, increased productivity and ice-rafted debris, and fell again following the establishment of interglacial conditions. A major event of lateral sediment redistribution, inferred from surplus 230Thxs inventories, occurred in the Makarov Basin during the deglaciation and may have been due to destabilization of slope and shelf sediments as sea level rose. I present the first high-resolution, radiocarbon-dated downcore records of sedimentary 231Pa/230Th from the Arctic Ocean. Low ratios indicate that 231Pa was exported from all sites during the late glacial period, with export decreasing during the deglaciation and Holocene. 231Pa/230Th measurements in cores from three continental slope sites show no evidence for a 231Pa sink related to boundary scavenging on the continental slopes. Holocene 231Pa/230Th ratios show a very significant variation by depth, with strong export of 231Pa at deep sites but little or no export at shallow sites, a result which echoes findings for the South Atlantic and the Pacific. The Arctic thus appears fundamentally similar to other ocean basins in its 231Pa and 230Th dynamics, despite its peculiar qualities of sea ice cover, low particle flux, and relatively isolated deep waters.My graduate work has been funded by NSF grants OCE-0402565 and OCE- 0550637 to Jerry McManus, ARC-0520073 to Bill Curry, and OCE-0118126 to Daniel McCorkle. My graduate education was also supported by an IODP Schlanger Ocean Drilling Fellowship, WHOI Fellowships from the WHOI Academic Programs Office, and an MIT Presidential Fellowship

Consumptive death in Victorian literature: 1830 - 1880.

PhDVictorian medical men, writers, relatives of the dying and consumptive sufferers themselves seized on the narrative potential of representations of the disease in a variety of ways. I argue that both medical and lay writers subscribed to a common set of beliefs about the disease and that medical knowledge, moreover, shared a common narrative way of knowing and understanding it. I analyse aspects of general clinical expository texts, including accompanying illustrations, showing how a narrative knowledge of death and the tubercular body was elaborated. Furthermore, I show how documents used in the compilation of medical statistics on the cause of death were fundamentally narrative through their reliance on case narratives. It is demonstrated that Dickens uses a seldom noticed consumptive death and decline to offset his heroine's development in Bleak House, in ways similar to those developed in Jane Eyre. Similarly, it is shown that Mrs Gaskell's use of a consumptive alcoholic 'fallen woman' unsettles her account of her heroine in Mary Barton. George Eliot's 'Janet's Repentance' is analysed, showing how the psychological struggle between an orientation towards life or death is played out across both alcoholism and consumption. I also examine how consumption presents a narrative opportunity whereby plots involving setbacks in love are resolved through women's consumptive deaths in popular fiction by Rhoda Broughton,Ladv Georgiana Fullerton and others. Through an examination of the Journal of Emily Shore and accounts of other actual deaths, I illustrate how experiences and accounts of consumptive deaths were structured and rendered intelligible through reliance on beliefs encountered in both fiction and medicine. In conclusion, the thesis alerts readers to the presence of signifiers of consumption in Victorian texts, showing how various narrative strategies are integral to any understanding of representations of its dying victim