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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Applications of time series analysis to geophysical data

Chave, Alan Dana January 1980 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Sciences, 1980. / Microfiche copy available in Archives and Science. / Vita. / Includes bibliographies. / by Alan Dana Chave. / Ph.D.
162

The application of inverse methods to problems in ocean circulation

Roemmich, Dean Howard January 1980 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Sciences, 1980. / Microfiche copy available in Archives and Science. / Vita. / Bibliography : leaves 122-129. / by Dean Howard Roemmich. / Ph.D.
163

Identifying and characterizing the immune cell populations of Atlantic bottlenose dolphins (Tursiops truncatus)

Unknown Date (has links)
Recently, there has been an increase in marine mammal mortalities, most commonly Atlantic bottlenose dolphins, Tursiops truncatus, which is an alarming indication of the health status of the marine ecosystem. Studies have demonstrated that some free-ranging dolphins exhibit a suppressed immune system possibly because of exposure to contaminants or infectious microorganisms. However, this research has been limited due to a lack of commercially available marine-specific antibodies. Therefore, the first chapter of this thesis aims to identify cross-reactive terrestrial-specific antibodies that could be used to phenotype and compare the immune cell populations of dolphins under human care and free-ranging dolphins. The second chapter aims to utilize terrestrial-specific growth factors and dendritic cell (DC) surface markers to generate, characterize, and compare ex vivo DCs from peripheral blood mononuclear cells (PBMCs) of dolphins under human care and free-ranging dolphins. In summary, I have identified differences within the PBMCs and ex vivo generated DCs of dolphins under human care and free-ranging dolphins that could potentially shed light on the impact of environmental contaminants and infectious microorganisms on immune cells which could lead to increased morbidity and mortality. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection
164

NATO’s eastward expansion and peace-enforcement role in the violent dissolution of Yugoslavia: 1994-2004.

Tsoundarou, Paul January 2008 (has links)
Since the end of the Cold War, political and geographical realities have changed considerably. One such reality was the balance of power between East and West, which was especially visible in Europe. The contest between rivals, the Warsaw Pact and the North Atlantic Treaty Organisation (NATO), was over. Ultimately, NATO found itself the pre-eminent security organisation in Europe. The new post-cold war environment forced questions about the appropriate role for NATO. However, that changed with both the process of NATO expansion into former Warsaw pact countries and the ethnic conflicts throughout the former Yugoslavia. NATO found a new purpose during the violent dissolution of Yugoslavia as ‘peace-enforcer’ in the Balkan region. The focus of this thesis is NATO’s role in peace-enforcement in the former Yugoslavia. It examines how NATO dealt with the end of the Cold War and the collapse of the Warsaw Pact. Specifically, how NATO managed to re-establish its relevance as a security organisation. NATO’s military intervention in Bosnia and Herzegovina and Kosovo were crucial in securing the end of hostilities in both those regions. NATO’s Implementation Force (IFOR), Stabilisation Force (SFOR) and Kosovo Force (KFOR) all played significant roles in subsequent peace-enforcement and peace-building roles in the region by suppressing violence through power projection and institution building. In 2001, NATO undertook a third operation in the Balkans, that time of a more limited nature, disarming ethnic Albanians in the Former Yugoslav Republic of Macedonia. NATO’s presence there also encouraged stability. This thesis argues that, ultimately, NATO maintained its relevance by the establishing a new role for itself after the Cold War through Eastward expansion and in suppressing ethnic conflict in the Balkans. Both these roles have been successful. The decisive interventions in Bosnia and Herzegovina, Kosovo and FYROM forced the belligerents to stop fighting. NATO’s subsequent enforcement of the peace has stopped each conflict from flaring up again. With NATO membership now including most of Europe, it remains the only viable security organisation on the continent. NATO’s effectiveness as a security organisation was demonstrated with its ability to end the conflict in the Balkans and providing a stable environment for the people of the region. This intervention was crucial to the definition of a new role for NATO in the post-Cold War world. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1320482 / Thesis (Ph.D.) -- University of Adelaide, School of History and Politics 2008
165

Pride and prejudice, practices and perceptions : a comparative case study in North Atlantic environmental history

Chittick, Sharla January 2011 (has links)
Due to escalating carbon-based emissions, anthropogenic climate change is wreaking havoc on the natural and built environment as higher near-surface temperatures cause arctic ice-melt, rising sea levels and unpredictable turbulent weather patterns. The effects are especially devastating to inhabitants living in the water-worlds of developing countries where environmental pressure only exacerbates their vulnerability to oppressive economic policies. As climatic and economic pressures escalate, threats to local resources, living space, safety and security are all reaching a tipping point. Climate refugees may survive, but they will fall victim to displacement, economic insecurity, and socio-cultural destruction. With the current economic system in peril, it is now a matter of urgency that the global community determine ways to modify their behaviour in order to minimize the impact of climate change. This interdisciplinary comparative analysis contributes to the dialogue by turning to environmental history for similar scenarios with contrasting outcomes. It isolates two North Atlantic water-worlds and their inhabitants at an historical juncture when the combination of climatic and economic pressures threatened their survival. During the sixteenth and seventeenth centuries, the Hebrideans in the Scottish Insular Gàidhealtachd and the Wabanaki in Ketakamigwa were both responding to the harsh conditions of the ‘Little Ice Age.’ While modifying their resource management, settlement patterns, and subsistence behaviours to accommodate climate change, they were simultaneously targeted by foreign opportunists whose practices and perceptions inevitably induced oppressive economic pressure. This critical period in their history serves as the centre of a pendulum that swings back to deglaciation and then forward again to the eighteenth century to examine the relationship between climate change and human behaviour in the North Atlantic. It will be demonstrated that both favourable and deteriorating climate conditions determine resource availability, but how humans manage those resources during feast or famine can determine their collective vulnerability to predators when the climate changes. It is argued that, historically, climate has determined levels of human development and survival on either side of the North Atlantic, regardless of sustainable practices. However, when cultural groups were under extreme environmental and economic pressure, there were additional factors that determined their fate. First, the condition of their native environment and prospect for continuing to inhabit it was partially determined by the level of sustainable practices. And, secondly, the way in which they perceived and treated one another partially determined their endurance. If they avoided internal stratification and self-protectionism by prioritising the needs of the group over that of the individual, they minimised fragmentation, avoided displacement, and maintained their social and culture cohesion.
166

Peat's secret archive : interpreting the geochemical and palaeodust record from Scottish peat as a potential index of North Atlantic storminess and Holocene climate change

Stewart, Helena K. January 2016 (has links)
Four continuous high-resolution peat records for the Holocene have been reconstructed across a ~300km transect from Shebster in Caithness to Yell in the Shetland Isles. These records describe the nature and extent of North Atlantic climate changes inferred from indicators of storminess and minerogenic aeolian dust, and are supported by radiogenic isotope analysis, tephrochronology and radiocarbon dating. The environmental changes at all four sites displays a significant degree of synchrony in response to changes in the position of the polar front jet (PFJ) stream and the phase of the North Atlantic Oscillation (NAO). Bromine concentrations in the peat, derived from sea spray, are used to reconstruct storm frequency and storm intensity, and mire surface wetness is used as an indicator of longer-term climate shifts. The results suggest a strong link between positive phases of the NAO and storminess. Subtle differences between the bromine concentrations and the mire surface wetness suggest that high intensity but perhaps less frequent periods of storminess are not necessarily associated with a wetter climate. Atmospheric minerogenic dust concentrations are used to reconstruct large-scale climate changes across the wider North Atlantic region. The results suggest a sympathy between dust activity and periods of glacial advance and a negative index of the NAO. Radiogenic isotope analysis suggests that the smallest particles may originate from Iceland.
167

Characteristics of upper heated oceanic layer from satellite observations

Mascarenhas, Affonso da Silveira January 1979 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Meteorology, 1979. / Microfiche copy available in Archives and Science. / Bibliography : leaves 81-83. / by Affonso da Silveira Mascarenhas, Jr. / M.S.
168

Variability in the North Atlantic Deep Western Boundary Current : upstream causes and downstream effects as observed at Line W / Variability in the NA DWBC : upstream causes and downstream effects as observed at Line W

Peña-Molino, Beatriz January 2010 (has links)
Thesis (Ph. D.)--Joint Program in Physical Oceanography (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2010. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 165-174). / The variability in the DWBC, its connection to the forcing in the northern North Atlantic and interaction with the Gulf Stream were explored from a combination of remote sensing and in-situ measurements in the western North Atlantic. Using satellite altimetry and Sea Surface Temperature (SST) we found evidence of the relation between changes in the Gulf Stream path and the variability in the temperature and velocity fields in the Slope Water. This relation was such that southward shifts of the main axis of the Gulf Stream were preceded by cold temperature anomalies and intensification of the southwestward flow. The analysis of 5.5 years of moored CTD and horizontal velocity data in the DWBC at 69 0W recorded during the period 2002-2008, showed that the variability along the DWBC is linked to changes in the dense water formation regions. The evolution of potential vorticity (PV) at the mooring site, characterized by a transition from deep to upper Labrador Sea Water (LSW), was similar to that observed in the Labrador Sea 6 to 9 years earlier, and imply spreading rates for the LSW that varied over time from 1.5 to 2.5cm/s. The time dependence of the spreading rates was in good agreement with changes in the strength of the DWBC at the mooring site. The evolution of the DWBC transport was explored in more detail from a 5- element moored array, also at 69'W. The results, for the period of 2004-2008, were consistent with the single mooring analysis. The variability measured from the array showed that upper, intermediate and deep water mass layers expand and contract at each other's expense, leading to alternating positive and negative PV anomalies at the upper-LSW, deep-LSW and Overflow Water (OW). Larger DWBC transports were associated with enhanced presence of recently ventilated upper-LSW and OW, rather than deep-LSW. The relative contribution of the different water masses to the observed circulation was investigated by inverting individual PV anomalies isolated from the observations. We found that changes in the depth-integrated circulation were mostly driven by changes in the OW. / by Beatriz Peña-Molino. / Ph.D.
169

The dynamics of mean circulation on the continental shelf

Shaw, Ping-Tung Peter January 1982 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Meteorology and Physical Oceanography, 1982. / Microfiche copy available in Archives and Science. / Vita. / Bibliography: leaves 221-225. / by Ping-Tung Peter Shaw. / Ph.D.
170

The dynamics and kinematics of the coastal boundary layer off Long Island

Pettigrew, Neal Robert January 1981 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Meteorology and Physical Oceanography, 1981. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND LINDGREN. / Vita. / Bibliography: leaves 255-261. / by Neal Robert Pettigrew. / Ph.D.

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