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Dinoflagellate biostratigraphy of the Cretaceous-Tertiary boundary, Round Bay, MarylandBenson, Don Gehr 07 July 2010 (has links)
The Monmouth and Brightseat Formations contain a rich and diverse dinoflagellate assemblage. Thirty-five genera and sixty-six species, of which two genera and eight species are new, are described in this study. The stratigraphic distribution of the taxa is summarized in Figure 4. The content of the assemblage changes suddenly at the Cretaceous-Tertiary boundary with thirteen species making the~r first appearance at or just above the boundary. Nineteen species cross the boundary and thirty-five species are restricted to the Cretaceous. The rather sudden change in the nature of the dinoflagellate assemblage at the boundary is interpreted by the author to indicate a paraconformable relationship between the Cretaceous and Paleocene sediments. The term paraconformity is used since there is little field evidence (a few pebbles, some lignite, and evidence of boring) indicating any extensive period of erosion at the boundary. / Master of Science
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Development of Improved Connection Details for Voided Slab BridgesJoyce, Patrick Conor 23 June 2014 (has links)
Adjacent voided slab bridges (AVSB) are economical systems for short spans. They provide the advantages of having low clearances due to their small section depths, accelerated construction times, and high torsional stiffness. The current longitudinal connection detail, a partial depth grouted shear key, has been known to fail in many of these bridges. The failure leads to reflective cracking in the wearing surface which allows chloride laden water to seep down through the joint, where it corrodes the reinforcement and prestressing strand. Ultimately, the failed keys lead to costly repairs and bridge replacements sooner than their proposed lifespan.
This research project aimed to develop a more durable longitudinal connection detail by using sub-assemblages to test five alternate connections. The objective was to find a connection that abated all cracking in the shear key, thus removing the need for transverse post-tensioning. The tested connections employed alternate connection shapes and two different mix designs of fiber reinforced high strength concretes. The results showed that each tested connection outperformed the current detail.
The findings of this research indicate that the longitudinal connection detail of adjacent member voided slab bridges should be modified. The modified version should be a blockout with lap splice connection detail utilizing a nonproprietary fiber reinforced high strength
concrete. / Master of Science
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Étude de facteurs cellulaires et viraux influençant le site d'assemblage et l'infectivité du virus d'immunodéficience humaine type 1 (VIH-1)Cervantes Acosta, Guillermo January 2001 (has links)
Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.
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Digital refit analysis of anthropogenically fragmented equine bone from the Schoningen 13 II-4 Deposits, GermanyHolland, Andrew D., Hutson, J.M., Villaluenga, A., Sparrow, Thomas, Murgatroyd, Andrew, García-Moreno, A., Turner, E., Evans, Adrian A., Gaudzinski-Windheuser, S., Wilson, Andrew S. 19 August 2022 (has links)
No / Excavation of the Schöningen lignite mine in Germany produced the earliest examples of hunting spears to date, and a large assemblage of anthropogenically fragmented faunal remains deposited in anaerobic lacustrine silt sediments during the Middle Pleistocene. The exceptional preservation of the assemblage makes the site of prime importance to our understanding of the behavioural, social and economic patterns of hominins in the Lower Palaeolithic of the Middle Pleistocene in Europe. This chapter describes the digital refitting analysis, part of the AHRC-funded Fragmented Heritage project, undertaken to address the logistical challenge posed by manually comparing individual bone fragments within the assemblage to identify refitting sequences. This logistical refit challenge uses the Schöningen assemblage to investigate the effectiveness of a digital refit approach to the analysis of large faunal assemblages. We describe the process from digitisation of the bone fragments by macro structured light scanning, digital segmentation of refitting surfaces, and digital comparison of the refitting and non-refitting surfaces to produce statistical matches. We discuss how taphonomic data can be visualised from the analysis and can be used to inform interpretation of the taphonomic histories of these faunal remains and the human behaviours associated with the formation of this unique assemblage. / The research was funded through an AHRC doctoral award as part of the AHRC Digital Transformations funded Theme Large Grant Fragmented Heritage (AH/L00688X/1) and through in-kind contributions from MONREPOS.
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Personal, Political, Pedagogic: Challenging the binary bind in archaeological teaching, learning and fieldworkCobb, H., Croucher, Karina 04 1900 (has links)
Yes / In this paper we consider how we can undercut the various binaries of gender and sexuality in
archaeological practice, and particularly in our teaching. We argue that taking an assemblage theory approach enables us to look at the multiplicity of identities of those practicing archaeology as different and intersecting assemblages that bring one another into being through their connections at different scales. In particular, we examine how this approach can be applied to archaeological pedagogy and how this in turn enables us to move away from modern binary distinctions about sex and gender identities from the "bottom up", fostering an approach in our students that will then go on to be developed in professional practice.
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Assembling archaeological pedagogy. A theoretical framework for valuing pedagogy in archaeological interpretation and practiceCobb, H., Croucher, Karina 26 November 2014 (has links)
No / Drawing on relational theoretical perspectives in archaeological discourse, this paper
considers how we can address the undervaluation of pedagogy and pedagogic
research in archaeology. Through examining the relationships between fieldwork,
teaching, and research, in light of Ingold’s concept of the meshwork and DeLanda’s
assemblage theory, the division between teaching and research is undermined,
and students and pedagogy are recentred as fundamental to the production of
archaeological knowledge. This paper provides a theoretical grounding for resituating
our current practices, suggests practical means for change, and highlights the benefit
to the archaeological discipline arising from a revaluation of archaeological pedagogic
research and an enmeshed understanding of archaeological practice.
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Technological, Refitting and Microwear of the Stone Artefact AssemblagePope, M., Davis, R., Evans, Adrian A. 12 August 2020 (has links)
No
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Scottish soldiers from the Battle of Dunbar 1650: a prosopographical approach to a skeletal assemblageMillard, A.R., Annis, R.G., Caffell, A.C., Dodd, L.L., Fischer, R., Gerrard, C.M., Graves, C.P., Hendy, J., Mackenzie, L., Montgomery, J., Nowell, G.M., Radini, A., Beaumont, Julia, Koon, Hannah E.C., Speller, C.F. 17 December 2020 (has links)
Yes / After the Battle Dunbar between English and Scottish forces in 1650, captured Scottish soldiers were imprisoned in Durham and many hundreds died there within a few weeks. The partial skeletal remains of 28 of these men were discovered in 2013. Building on previous osteological work, here we report wide-ranging scientific studies of the remains to address the following questions: Did they have comparable diet, health and disease throughout their lives? Did they have common histories of movement (or lack of movement) during their childhoods? Can we create a collective biography of these men?
Strontium and oxygen isotope analysis of tooth enamel investigated childhood movement. Carbon and nitrogen isotope analysis of incrementally sampled dentine addressed childhood diet and nutrition. Metaproteomic analysis of dental calculus investigated oral microbiomes and food residues; this was complemented by microscopic analysis of debris in calculus from ingested materials. Selected individuals were examined for dental microwear. The extent of hydroxylation of proline in collagen was examined as a potential biomarker for scurvy. An osteobiography for each man was created using the full range of data generated about him, and these were synthesised using an approach based on the historical method for a collective biography or prosopography.
The childhood residences of the men were primarily within the Midland Valley of Scotland, though some spent parts of their childhood outside the British Isles. This is concordant with the known recruitment areas of the Scottish army in 1650. Their diets included oats, brassicas and milk but little seafood, as expected for lowland rather than highland diets of the period. Childhood periods of starvation or illness were almost ubiquitous, but not simultaneous, suggesting regionally variable food shortages in the 1620s and 1630s. It is likely there was widespread low-level scurvy, ameliorating in later years of life, which suggests historically unrecorded shortages of fruit and vegetables in the early 1640s. Almost all men were exposed to burnt plant matter, probably as inhaled soot, and this may relate to the high proportion of them with of sinusitis. Interpersonal violence causing skeletal trauma was rare. Based on commonalities in their osteobiographies, we argue that these men were drawn from the same stratum of society.
This study is perhaps the most extensive to date of individuals from 17th century Scotland. Combined with a precise historical context it allows the lives of these men to be investigated and compared to the historical record with unprecedented precision. It illustrates the power of archaeological science methods to confirm, challenge and complement historical evidence. / The excavation and post-excavation
programme was primarily funded by Durham
University, with the palaeoproteomic analysis
funded through the Wellcome Trust www.
wellcome.ac.uk (108375/Z/15/Z to CFS).
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Spatial and Temporal Dynamics of Larval Fish Assemblages in the Strait of GeorgiaGuan, Lu 30 April 2015 (has links)
For marine fishes, the early larval phase is considered a critical stage for survivorship and recruitment. The spatial and temporal dynamics of larval fish assemblages can influence their success and trophic structure of marine communities and entire ecosystems. This thesis will provide the first characterization of larval fish assemblage in the Strait of Georgia (SoG) in terms of diversity, abundance and composition, and their variability over multiple temporal scales, as well as the first quantification of variability in larval fish distribution in the SoG across multiple spatial scales. On the interdecadal scale, a significant decrease in larval abundance of several dominant fish taxa (Pacific hake, walleye Pollock, northern smoothtongue and rockfishes) contributed to a decline in total larval abundance and turnover in the composition structure between the early 1980s and the late 2000s. In contrast, both abundance and the relative composition of flatfishes and several demersal forage fish taxa increased during the same period. On interannual scales, abundance, diversity and community structure of the spring larval assemblages varied dramatically through 2007-2010, a period which alternated between strong La Niña and El Niño events. Higher overall larval concentrations were associated with warm conditions in the SoG in 2007 and 2010, while the lowest larval concentration was associated with cooler condition in 2009. Examination of associations between larval fish assemblages and environmental fluctuations suggests a potential influence of large-scale climate processes between the early 1980s and the late 2000s, but a primary association with local environmental
factors on interannual scales. Spatial patterns in larval density of three dominant fish taxa (Pacific herring, Pacific hake and northern smoothtongue) were mostly structured on predefined broad (> 40km) and medium (20~40km) scales. Although their scale-dependent associations with environmental factors varied interannually, larval distributions in the central-southern SoG were generally associated with salinity, temperature and vertical stability of water column in the upper layer (0-50m). Our results emphasize the role of local estuarine circulation in structuring hierarchical spatial distributions of planktonic fish larvae in the SoG. These findings will provide considerable implications in fisheries resource management and conservation strategies. / Graduate / 0416 / 0329 / guanlu129@gmail.com
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Calibration and Application of the MagEval geothermometer in sedimentary rocks / Calibration et Application du géothermomètre magnétique MagEval dans les roches sédimentaireKars, Myriam 05 January 2012 (has links)
Pour évaluer la température d’enfouissement subie par les roches sédimentaires, une large gamme de géothermomètres est disponible, basés sur les constituants organiques ou minéralogiques de ces roches. Comme pour toutes les techniques expérimentales, elles présentent des avantages et des inconvénients. Dans cette thèse, nous utilisons une approche magnétique pour estimer la température d’enfouissement. Dans une première partie, nous avons étudié l’assemblage magnétique de puits sélectionnés à travers le monde pour mieux caractériser le géothermomètre magnétique MagEval. Deux calibrations ont pu être établies. Pour décrire la relation entre la température maximale d’enfouissement subie par les roches et leur assemblage magnétique, nous avons réalisé des expériences de chauffe en laboratoire de 50 à 130°C sur des argilites non métamorphosées. Les chauffes expérimentales ont montré que des nanominéraux magnétiques sont continuellement produits avec la température. Dans une deuxième partie, nous avons étudié les propriétés magnétiques des roches sédimentaires dans deux sites géologiques analogues pétroliers : le bassin des Grès d’Annot dans le SE de la France (température d’enfouissement 60-250°C) et les chaînes plissées de la Valley & Ridge Province dans les Appalaches, Etats-Unis (température d’enfouissement _120-200°C). Ces études suggèrent une évolution des principaux minéraux magnétiques avec la température. Magnétite, nanogoethite et pyrrhotite sont principalement formées. Les différents résultats obtenus dans cette thèse nous ont permis de proposer une évolution des minéraux magnétiques en fonction de la maturité des roches et de la température. / To evaluate the burial temperature experienced by sedimentary rocks, a wide range of geothermometers is available, based on both organic and inorganic constituents of these rocks. Like all experimental techniques, they show limitations. In this thesis, we used a magnetic approach to estimate burial temperature. In a first part, we studied the magnetic assemblage of selected boreholes over the world to better characterize the magnetic geothermometer MagEval. Two calibrations were established. To assess the relationship between the peak burial temperature experienced by the rocks and their constitutive magnetic minerals, we conducted laboratory heating experiments from 50 to 130°C on unmetamorphosed claystones. The experimental heating showed that nano magnetic minerals are continuously produced with temperature. In a second part, we investigated rockmagnetic properties of sedimentary rocks from two geological plays of petroleum interest : the Grès d’Annot basin in SE France (burial temperature 60-250°C) and the fold-and-thrust belts of the Valley & Ridge Province in the Appalachians, USA (burial temperature _120-200°C). These studies suggested an evolution of the main magnetic minerals with temperature. Magnetite, nanogoethite and pyrrhotite are mainly formed. All the conducted analyses lead us to propose an evolution of the magnetic minerals as a function of the maturity of the rocks and temperature.
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