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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.
261

Functional morphology and evolution of the adapiform dentition, with particular emphasis on the Asian Sivaladapidae

White, Jessica Lynn. January 2006 (has links)
Thesis (Ph.D.)--University of Iowa, 2006. / Supervisor: Russell L. Ciochon. Includes bibliographical references (leaves 228-242).
262

Environnements paraliques à ambre et à végétaux du Crétacé nord-aquitain (Charents, sud-ouest de la France) /

Perrichot, Vincent. January 2005 (has links)
Thesis (doctoral)--Université de Rennes, 2003. / Includes bibliographical references. Also available on the World Wide Web.
263

The Devonian corals of the Yarrol province, Eastern-central Queensland /

Blake, Paul Raymond. January 2006 (has links) (PDF)
Thesis (Ph.D.) - University of Queensland, 2005. / Includes bibliography.
264

Paleoecology of fossil species of canids (Canidae, Carnivora, Mammalia)

OKŘINOVÁ, Isabela January 2013 (has links)
There were reconstructed phylogeny of recent and fossil species of subfamily Caninae in this study. Resulting phylogeny was used for examining possible causes of cooperative behaviour in Caninae. The study tried tu explain evolution of social behavior in canids.
265

Urban air quality management and planning in South Africa

Scorgie, Yvonne 05 November 2012 (has links)
Ph.D. / Fossil fuel burning within residential, industrial and power generation sectors represents a persistent source of air pollution within many parts of South Africa, with the contribution of road transport emissions becoming increasingly important. Additionally, biomass burning, including agricultural burning and wild fires, represents an intermittent but seasonally significant source of atmospheric emissions. Effective air pollution control was historically hindered by the absence of enabling legislation and cooperative governance. The promulgation of the National Environmental Management: Air Quality Act, Act 39 of 2004 represented a major step forward in the evolution of air quality management within South Africa. The historical debate regarding the practicability of effective air quality management is however ongoing. South Africa‟s continued dependence on coal to support its energy-intensive industrial and mining sectors, continued household fuel burning for space heating and cooking purposes within a number of areas, and the dire need for employment creation and focus on rapid development continue to challenge the realisation of air quality improvements. This study investigates the multiple factors contributing to the degradation of air quality in South Africa, and the consequent human health, environmental and economic effects of this pollution. The study critically examines legal, technical and social measures implementable within a tailored system of air quality management which is compatible with socio-economic growth. This thesis integrates and expands on pertinent components of several individual research projects completed by the author during her tenure as a doctoral candidate. The research projects were completed during the period (2002 – 2009) on behalf of various parties including national and local government, standards setting bodies and private organisations. Quantification of health risks associated with significant anthropogenic sources within several South African conurbations, covering 40% of the national population, and the establishment of cost-optimised air pollution interventions, forms a key component of the thesis. In this externalities study, emissions were estimated and effects and associated costs quantified for household fuel burning, power generation, industrial and commercial fuel burning and road transport. Total direct health costs related to inhalation exposures to fuel burning emissions were estimated to be of the order of 3.5 billion 2002 Rands per annum across health effects, conurbations and source groupings assessed. Household fuel burning was estimated to be responsible for about 68% of the total health costs estimated across all conurbations, vehicle emissions for 13%, industrial and commercial fuel burning for 13%, and power generation for about 6%. Emission reduction opportunities were identified and assessed for residential fuel burning, coalfired power generation, road transport, coal-fired industrial boilers and specific individual industries. It was concluded that significant health effect reductions could cost-effectively be achieved through addressing residential fuel burning as a priority. Lower benefit-cost ratios associated with industrial and vehicular interventions are due, in part, to these fuel burning sources having been more effectively regulated historically. The need for effective management of industrial and vehicle emissions is however supported. Based on international experience and local trends in vehicle activity, the contribution of transport emissions will become increasingly ix significant if not adequately addressed. Industrial process emissions unrelated to fuel burning may include significant emissions of criteria pollutants, in addition to trace releases of a wide range of hazardous air pollutants. Internationally, actions taken to address air pollution problems have met with mixed results. Failure to integrate economic considerations into air quality management planning, and to integrate air quality considerations into development planning represent key weaknesses in the strategies implemented. A contribution is made in this thesis by highlighting such lessons and proposing legal, technical and social measures which, when implemented within a rational system of air quality management, are suited to addressing complex air pollution sources without negatively affecting socio-economic prosperity and equity. Components of an effective, affordable and equitable emissions control policy proposed for adoption within South Africa include phased national standards setting, compliance promotion and self-monitoring, market-based instruments, and the implementation of risk-based enforcement and compliance monitoring strategies.
266

Upper Llandovery brachiopods from Shropshire

Cocks, Leonard Robert Morrison January 1965 (has links)
No description available.
267

Corals from the Rundle formation (Mississippian) of Banff, Alberta

Frebold, Fridtjof Albert January 1955 (has links)
This thesis contains descriptions and illustrations of six genera and seven species of fossil corals collected by the writer on Mount Norquay, Banff National Park, Alberta. A brief discussion of the fossil locality and stratigraphy of the Rundle formation in that area is given. As a result of statistical research and graphic representation, a new species Faberophyllum multiseptatum is described. The new species is closely related to F. languidum, F. leathamense, F. pisgahense, and F. araneosum. The species Ekvasophyllnm banffense is proposed, and the species Lophyphyllum ? cascadense Warren is redescribed and referred to the genus Ekvasophyllum. The genera Triplophyllites and Cyathoclisia, which previously have not been described from Canada, are recognized and briefly discussed. The descriptions of Lithostrotion whitneyi and Lithostrotionella banffensis are revised and adequately illustrated. From the study of corals from the upper Rundle formation the writer concludes that these may be important horizon markers, and recommendations are made for more extensive and detailed work on this subject. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
268

The holocene ostracods of the Agulhas Bank, South Africa : their classification, distribution and ecology

Conway-Physick, Jessica Ann January 1995 (has links)
Bibliography: pages 69-77. / An analysis of the Holocene ostracod fauna of the Agulhas Bank has been carried out on seventy-three surficial sediment samples. Sixty-six species of Ostracoda have been recorded, of which fifty-nine species are accounted for in forty genera and the remaining seven species are of indeterminate classification. The species are described and their distribution and ecology is given. An. analysis of the sedimentology, as well as an oceanographic analysis of the bottom water on the Agulhas Bank, has provided environmental parameters for each sediment sample location, enabling relationships to be described between ostracod faunas and environmental conditions. Quantitative factor analysis has been carried out on the twenty-four most abundant species, generating seven factor associations relating ostracod assemblages to a set of environmental parameters. The independent variables analyzed were the temperature, salinity and dissolved-oxygen content of the bottom water, as well as the sand content of the sediment. Contour maps of these variables have been drawn up using SADCO data for the oceanographic variables, and the sediment samples to calculate the sand content. The overall oceanography of the Agulhas Bank has been analyzed by relating the environmental parameters generated at each location to the water masses present on the shelf, and to the oceanic currents affecting them. Finally, the seven factor associations generated have been related directly to the substrate types, the water masses, and the currents present on the Agulhas Bank.
269

The osteology and relationships of aquatic eosuchians from the Upper Permian of Africa and Madagascar /

Currie, Philip J. January 1981 (has links)
No description available.
270

Calcareous nannofossil and foraminiferal analysis of the middle to upper cretaceous Bathurst Island Group, Northern Bonaparte Basin and Darwin Shelf, Northern Australia /

Campbell, Robert John. January 2003 (has links)
Thesis (Ph.D.)--University of Western Australia, 2003.

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