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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.
381

The determination of a series of ages of a Hawaiian volcano by the potassium-argon method / Ages of a Hawaiian volcano

Funkhouser, John Gray January 1966 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii, 1966. / Bibliography: leaves 156-168. / xiii, 168 l illus. (part mounted), tables
382

Utility of leaf wax normal alkanes for lacustrine sediment chronology and for reconstruction of holocene paleovegetative changes in Hawaiʻi : an application of robust molecular radiocarbon and stable carbon isotopic techniques

Uchikawa, Joji January 2006 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 165-166). / xii, 166 leaves, bound col. ill., maps 29 cm
383

Family ties: molecular phylogenetics, evolution and radiation of flatworm parasites (Monogenea: capsalidae).

Perkins, Elizabeth January 2010 (has links)
The Capsalidae is a diverse family of ectoparasites of marine fish (Platyhelminthes: Monogenea). It is a large family with approximately 180 described species and many more yet to be discovered. Capsalids have a global distribution and parasitise a diversity of hosts from the Chondrichthyes to bony fishes. A morphological classification exists for the family based on a few key characters such as testes number, their arrangement and morphology of the posterior attachment organ (haptor). Phylogenetic relationships within the family and its position within the Monogenea are largely unexplored. I have used various molecular phylogenetic techniques to resolve relationships and explore the evolution and radiation of this family. Specimens from the Capsalidae and other monogenean families (outgroups) were obtained through fresh collections and generous donations by other parasitologists. Specimens were stored in 95% undenatured ethanol. Three unlinked nuclear genes (28S ribosomal RNA, Histone 3 and Elongation Factor 1 α) and two mitochondrial genes (Cytochrome Oxidase 3 and Cytochrome B) were amplified for 78 capsalid taxa in 28 genera representing all nine subfamilies and 30 outgroup taxa (eight Polyopisthocotylea and 22 Monopisthocotylea). Analyses showed the Capsalidae is monophyletic, with the sister group remaining unresolved. Some analyses supported Gyrodactylidae and Udonellidae as the sister group but in other analyses, it was unresolved with the Monocotylidae and Microbothriidae also possible sister groups. The Capsalinae, Encotyllabinae and Nitzschiinae are monophyletic, but analyses did not support monophyly for the Benedeniinae, Entobdellinae and Trochopodinae. Monophyly was supported for Capsala, Capsaloides, Encotyllabe, Entobdella, Listrocephalos, Neobenedenia, Nitzschia and Tristoma, but Metabenedeniella is paraphyletic and Benedenia and Neoentobdella are polyphyletic. Comparisons of the distribution of character states for the small number of morphological characters on a molecular phylogeny show a high frequency of apparent homoplasy. Consequently the current morphological classification for the Capsalidae shows little correspondence with the phylogenetic hypotheses I present. I also sequenced the first complete mitochondrial (mt) genome for a capsalid species, Benedenia seriolae. The mt genome of B. seriolae shows some tRNA rearrangements in comparison to three Gyrodactylus spp. (Gyrodactylidae), the only other complete monopisthocotylean mt genomes sequenced. It also lacks the duplicated, conserved non-coding regions present in Gyrodactylus spp. making the genome smaller in size. I combined this genome with other available platyhelminth mt genomes to investigate the monophyly of Monogenea and the evolution of diet across the Neodermata. Results confirm paraphyly for the Monogenea and also suggest paraphyly for the epidermal feeding Monopisthocotylea. I hypothesise that the Monopisthocotylea represent the first shift to parasitism in the Neodermata from a free living ancestor and following this, there was a dietary shift to blood feeding (Polyopisthocotylea). The Digenea and Cestoda independently evolved dietary specialisations to suit their diverse microhabitats and broad range of vertebrate final hosts. Using Elongation Factor 1 α I have estimated molecular divergence dates for the Neodermata, Monogenea and Capsalidae. Molecular clock analyses estimate the Neodermata diverged from the free living platyhelminths 513 million years ago (mya) (95% HPD [highest posterior density]: 473–605) before the appearance of vertebrates in the fossil record. The Monogenea diverged from the other neodermatan classes 441 mya (95% HPD: 420–547) coinciding with the appearance of fish in the fossil record. The most recent common ancestor of the Capsalidae arose approximately 235 million years ago (95% HPD: 200–274) following the Permian/Triassic extinction event and coinciding with the diversification of bony fishes in the marine environment. I compared the capsalid phylogeny to a phylogeny of fishes that I generated using eight nuclear and three mt genes to explore the evolution and the radiation of the Capsalidae across fishes. There is no significant global signal of coevolution with only five parasite-host associations that may be a result of coevolution. Estimated molecular divergence dates are also compared and do not reveal temporal congruence. Radiation of the family may have been driven by host switching constrained by shared host ecology, biology, behaviour and plasticity in morphological adaptations by the parasites. This study advances our understanding of the evolution of this monogenean family and provides insights into the evolution of the Neodermata and the complicated realities of reconstructing the evolutionary history of parasitic groups. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1522353 / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2010
384

The Pleistocene glaciations of the Cradle Mountain Region, Tasmania

Thrush, Michael January 2008 (has links)
Research Doctorate - Doctor of Philosophy (PhD) / The northern Central Highlands region of Tasmania extending north from Cradle Mountain to the Middlesex Plains shows evidence of three glacial stages, with the final stage consisting of several ice advance phases. From oldest to youngest these have been named the Middlesex Glaciation, the Sunshine Glaciation and the Cradle Glaciation. Cosmogenic exposure-age dating of boulders and ice-abraded bedrock, radiocarbon dating of post-glacial organic deposits, and relative dating techniques have resulted in assignment of the following ages for the events: Middlesex Glaciation, MIS 10; Sunshine Glaciation, MIS 6 and the Cradle Glaciation having MIS 3 and MIS 2 phases. The Cradle Glaciation correlates with the global Last Glaciation. Exposure-age dating of three of the Cradle Glaciation ice advance phases indicates that the Pencil Pine Phase predates 38.9±4.0 ka, the Dove Phase occurred ca. 29.2±1.4 ka, and the Cradle Valley Phase occurred between >19.7±1.1 – 17.6±1.0 ka. At least two undated retreat/readvance phases followed the Cradle Valley Phase. Deglaciation of the area was probably complete considerably before 11.2 ka. The recognised glacial events decreased in areal extent in each successive advance. Using the 0°C summer mean isotherm as the base for the altitude of the equilibrium line altitude, the regional snowline, regional snowline depression and temperature depression for each of the events were: Middlesex Glaciation, 942 m/1616 m/10.5°C; Sunshine Glaciation, 984 m/1574 m/10.23°C; Pencil Pine Phase, 1010 m/1548 m/10.06°C; Dove Phase, 1050 m/1508 m/9.8°C; and the Cradle Valley Phase, 1060 m/1498 m/9.74°C. The geomorphic evidence and dating of several phases of the Cradle Glaciation indicates a complex history of ice advances for Tasmania during the Last Glaciation.
385

A Geomorphological and Sedimentological Investigation into the Glacial Deposits of the Lake Clearwater Basin, Mid Canterbury, New Zealand.

Evans, Michael Douglas January 2008 (has links)
This thesis presents the findings of a combined geomorphological, sedimentological and geochronological investigation into the glacial history of the Clearwater Basin, Mid Canterbury, New Zealand. The study demonstrates that a thick wedge of glacial and paraglacial sediments are preserved in the valley. These are >100m thick and preserve evidence of at least 3 glacial phases (>180ka). The study presents a new and detailed geomorphology map for the Clearwater valley and adjacent areas and has added 17 new recessional positions to the local glacial record. Surface Exposure Dating (SED) has been used to directly date the moraines of the Clearwater Basin providing the first detailed chronology for glacial moraine in this area. In total 31 cosmogenic ages from 9 separate moraines are presented. The results demonstrate that the LGM advance is the Trinity moraine of Mabin (1980) and not the Hakatere moraine as previously assumed and that the LGM was achieved at or about 23ka. The Clearwater glacier receded up valley between 23 and 13ka with some indication of accelerated retreat after c.16ka. The correlation to the adjacent Lake Heron Valley is also revised.
386

Development and application of optical dating using quartz and potassium-feldspar from quaternary sediments

Li, Bo, January 2007 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2008. / Also available in print.
387

Holocene evolution of a hypersaline lake Lagkor Tso, western Tibet /

Lee, Ting, Jennifer, January 2008 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2008. / Also available in print.
388

Archaeology and historical problems of the Second Intermediate Period

Williams, Bruce, January 1900 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Near Eastern Languages and Civilizations, December 1975. / Available in PDF. Includes bibliographical references.
389

The application of artificial thermoluminescence to uranium exploration and uranium ore genesis studies /

Hochman, Mark Brett McEwen. January 1989 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, Dept. of Geology and Geophysics, 1990. / Typescript (Photocopy). Includes copies of 5 published papers co-authored by the author in back. Includes bibliographical references (leaves 214-230).
390

Interpersonal perception of values in dating couples and implications for relationship quality and satisfaction /

Brandlmayr, Dawn E. January 2007 (has links)
Thesis (Ph.D.)--York University, 2007. Graduate Programme in Psychology. / Typescript. Includes bibliographical references (leaves 120-130). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:NR29319

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