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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.
41

Landfill Site Selection By Using Geographic Information Systems

Sener, Basak 01 September 2004 (has links) (PDF)
One of the serious and growing potential problems in most large urban areas is the shortage of land for waste disposal. Although there are some efforts to reduce and recover the waste, disposal in landfills is still the most common method for waste destination. An inappropriate landfill site may have negative environmental, economic and ecological impacts. Therefore, it should be selected carefully by considering both regulations and constraints on other sources. In this study, candidate sites for an appropriate landfill area in the vicinity of Ankara are determined by using the integration of Geographic Information Systems and Multicriteria Decision Analysis. For this purpose, sixteen input map layers including topography, settlements (urban centers and villages), roads (Highway E90 and village roads), railways, airport, wetlands, infrastructures (pipelines and power lines), slope, geology, land use, floodplains, aquifers and surface water are prepared and two different MCDA methods (Simple Additive Weighting and Analytic Hierarchy Process) are implemented in GIS environment. Comparison of the maps produced by these two different methods shows that both methods yield conformable results. Field checks also confirm that the candidate sites agree well with the selected criteria.
42

Genesis Of The Karaali (ankara, Turkey) Fe-cu Sulfide Mineralization

Imer, Ali 01 January 2006 (has links) (PDF)
With the closure of Neo-Tethys in the Early Tertiary, oceanic crustal material was accreted along the izmir-Ankara-Erzincan Suture Zone. The Ankara m&eacute / lange developed within this suture zone and contains Cretaceous ophiolitic fragments, some of which host significant Fe-Cu sulfide mineralization. Such mineralization is observed as massive to disseminated pyrite-chalcopyrite hosted by pillow to massive basalts in a dismembered and tectonically imbricated ophiolite block near Karaali, Ankara. Basaltic host rocks lack most of their primary mineral assemblages and textural relationships. As a consequence of greenschist-facies metamorphism and hydrothermal alteration, the basalts were strongly albitized and propylitized prior to late-stage argillic alteration, which is proximal to the main mineralized zone. Sulfide mineralization occurs in a massive sulfide lens and laterally extensive, 10-meter-thick zone of anastomosing quartz-sulfide veins. Other than pyrite and chalcopyrite, bornite, covellite and sphalerite also occur as minor sulfide phases, and the source of sulfur is determined to have been magmatic on the basis of 34S isotope analyses. A series of geochemical analyses suggest that the basaltic host rocks formed within a subduction-related tectonic setting, and the mineralization is thought to have formed during a medium-temperature hydrothermal event which was followed by another later period of low-temperature hydrothermal activity. Field, petrographical and geochemical evidence show that the Karaali Fe-Cu mineralization is genetically correlative with the Cyprus and K&uuml / re massive sulfide deposits, and may be classified as a Cyprus-type massive sulfide deposit.
43

Market Share Analysis For Shopping Centers In Ankara

Yavuzer, Ipek 01 January 2005 (has links) (PDF)
In the last decade, the changes in living styles of people and shopping activities brought a new concept, &ldquo / shopping center&rdquo / . By the time the numbers of shopping centers increased and this big consumption market created a great competition among the investors. The investors had the necessity of examining their market share within the market and other social and spatial factors for the feasibility of their shopping centers. In this thesis considering the need of such a study, a market share analysis is carried out to determine the market share of shopping centers within the competition, analyze the important facts of the market share, estimate the market capacity and potential market regions. Ankara is chosen as the study area since it has an increasing trend for the development of shopping centers. Tthe study is carried out for Armada, Bilkent and 5M Migros shopping centers since they serve for the whole city and have different functions such as recreation, restaurants, cultural activities together with shopping activities. For the analysis a gravity model developed by Lakshmanan and Hansen is used. The model estimates the market share of the centers among regions considering the factors, as accessibility in terms of cost and time, economic conditions of regions, attractiveness of shopping centers and competitors of the market. For the application process Geographic Information Systems ESRI Arc GIS 8.1 and ESRI ArcView 3.2 are used as software to store and manipulate data, build regulations on road network structure, calculate distances and costs, and present maps and results.
44

Design Of Water Distribution System By Optimization Using Reliability Considerations

Akdogan, Tevfik 01 June 2005 (has links) (PDF)
ABSTRACT DESIGN OF WATER DISTRIBUTION SYSTEM BY OPTIMIZATION USING RELIABILITY CONSIDERATIONS Akdogan, Tevfik Department of Civil Engineering Supervisor : Assoc. Prof. Dr. Nuri Merzi April 2005, 91 pages In spite of a wide research, design of water distribution networks are not realized using optimization techniques. One reason for this fact is, design of water distribution networks is evaluated, mostly, as a least-cost optimization problem where pipe diameters being the only decision variables. The other motivation for preferring the traditional modeling practice is that, existing optimization algorithms are not presented to the user as friendly as it should be. In fact, water distribution systems are very complex systems such that it is not easy to obtain least-cost design systems considering other constraints such as reliability, in addition to classical constraints related to hydraulic feasibility, satisfaction of nodal demands and requirement of nodal pressures. This study presents a user-friendly package concerning the design of water distribution networks by optimization using reliability considerations / this works employs the algorithm proposed by Goulter and Coals (1986). At the end, a skeletonized network design is offered / various costs are estimated in regard to the degree of reliability.
45

An Analysis Of The Conservation Of The Twentieth Century Architectural Heritage In Turkey: The Case Of Ankara

Elmas, Nimet 01 July 2005 (has links) (PDF)
This thesis examines the twentieth century architecture from the perspective of conservation. The criteria of conservation have changed as the idea of conserving a single monument has progressed into the acceptance of the need to conserve different cultural properties and the field has been enriched with new notions, such as the twentieth century architectural heritage. The main concern in this thesis is to present these current debates about and developments in the conservation of the twentieth century architecture in the world and in Turkey. Such a study initially entails to deal with the basic issues of conservation, the twentieth century architecture in the world and in Turkey and its conservation, and to form a detailed documentation of registered twentieth century buildings. With reference to the information gathered from this study and by examining the registration decisions of buildings the aim is to analyse the practice of the conservation of the twentieth century architecture in Ankara as an exemplary case of the current situation of the field in these terms in Turkey.
46

&quot / the Citadel Of Ankara&quot / :aspects Of Visual Documentation And Analysis Regarding Material Use

Suluner, Hasan Sinan 01 November 2005 (has links) (PDF)
This thesis examines the history, written sources and physical aspects of the citadel at Ankara with respect to building materials, masonry styles, design and topography. The distribution of different types of building materials in selected areas are analyzed and documented by using modern methods.
47

Breeding Biology, Population Size And Spatial Distribution Of A Common Nightingale (luscinia Megarhynchos Brehm, 1831) Population At Yalincak (ankara)

Ozbahar, Ilker 01 December 2005 (has links) (PDF)
Many bird populations are known to show strong territoriality as well as high site fidelity during breeding. The Common Nightingale (Luscinia megarhynchos) is one of many such migratory species that annually occupies the same favourable habitat. Especially dominant males prefer to breed in the same area every year, and high fidelity probably assures high breeding success. This study aims to investigate breeding biology, population size and spatial distribution of nightingales at a small area in Yalincak within the METU campus grounds (Ankara, Turkey). From 2003 to 2005, birds were captured and marked with metal or colour rings or radio tags for monitoring. Analyses were carried out on 77 individuals, including ringing data from the previous two years. Phenology of the study population was characterized by early arrival of males in late April, followed one week later by females. Nesting immediately followed and the first young fledged in early June. Second broods were also recorded. Most birds apparently left for the south within August. The population in the 2.65 ha large area was estimated to be about 20-25 individuals. However, only 2-4 breeding territories were present and a large proportion of floaters existed. Territory sizes were smaller than reported elsewhere. Annual survival rate was 0.424 &amp / #61617 / 0.121. Contrary to previous knowledge, taxonomically the Yalincak population belonged to subspecies africana although more westerly subspecies could be recorded during migration. This study revealed the importance of small but productive biotopes as important breeding habitats for passerines. It also showed that a few highly successful individuals may contribute out of proportion to the next generation.
48

Memory, Identity, Home: Self-perception Of Identity Among The Armenian And Jewish Communities In Ankara

Bal, Ozgur 01 May 2006 (has links) (PDF)
This thesis explores the identity perceptions of the Armenian and Jewish communities in the context of Ankara. Purpose of the study is to understand the ways the members of these communities experienced the social, spatial, political and cultural changes in the capital-city after the establishment of Turkish nation-state / and in what ways they draw on these experiences in terms of their identifications, self-understanding, and feelings of belonging. For this purpose, life-story narratives of people who were born in the early Republican era and of the following generation were collected through oral history methodology. As a result of the analyses of these narratives, multiple, fluid, contextual, and contingent character of identity in terms of the Armenian and Jewish communities in Ankara is pointed, and it is concluded that community identity for the members of these communities was symbolically constructed.
49

Vergleich von rekombinanten Vaccinia- und DNA-Vektoren zur Tumorimmuntherapie im C57BL/6-Mausmodell

Johnen, Heiko January 2002 (has links)
In der vorliegenden Arbeit wurden Tumorimpfstoffe auf der Basis des Plasmid-Vektors pCI, modified vaccinia virus Ankara (MVA) und MVA-infizierten dendritischen Zellen entwickelt und durch Sequenzierung, Western blotting und durchflußzytometrische Analyse überprüft. Die in vivo Wirksamkeit der Vakzinen wurde in verschiedenen Tumormodellen in C57BL/6 Mäusen verglichen. Die auf dem eukaryotischen Expressionsvektor pCI basierende DNA-Vakzinierung induzierte einen sehr wirksamen, antigenspezifischen und langfristigen Schutz vor Muzin, CEA oder beta-Galactosidase exprimierenden Tumoren. Eine MVA-Vakzinierung bietet in den in dieser Arbeit durchgeführten Tumormodellen keinen signifikanten Schutz vor Muzin oder beta-Galactosidase exprimierenden Tumoren. <br /> <br /> Sowohl humane, als auch murine in vitro generierte dendritische Zellen lassen sich mit MVA &ndash; im Vergleich zu anderen viralen Vektoren &ndash; sehr gut infizieren. Die Expressionsrate der eingefügten Gene ist aber gering im Vergleich zur Expression in permissiven Wirtszellen des Virus (embryonale Hühnerfibroblasten). Es konnte gezeigt werden, daß eine MVA-Infektion dendritischer Zellen ähnliche Auswirkungen auf den Reifezustand humaner und muriner dendritischer Zellen hat, wie eine Infektion mit replikationskompetenten Vakzinia-Stämmen, und außerdem die Hochregulation von CD40 während der terminalen Reifung von murinen dendritischen Zellen inhibiert wird. Die während der langfristigen in vitro Kultur auf CEF-Zellen entstandenen Deletionen im MVA Genom führten zu einer starken Attenuierung und dem Verlust einiger Gene, die immunmodulatorische Proteine kodieren, jedoch nicht zu einer Verminderung des zytopathischen Effekts in dendritischen Zellen. <br /> <br /> Die geringe Expressionsrate und die beobachtete Inhibition der Expression kostimulatorischer Moleküle auf dendritischen Zellen kann für eine wenig effektive Induktion einer Immunantwort in MVA vakzinierten Tieren durch cross priming oder die direkte Infektion antigenpräsentierender Zellen verantwortlich sein.<br /> <br /> Durch die Modifikation einer Methode zur intrazellulären IFN-gamma Färbung konnten in vakzinierten Mäusen tumorantigenspezifische CTL sensitiv und quantitativ detektiert werden. Die so bestimmte CTL-Frequenz, nicht jedoch die humorale Antwort, korrelierte mit der in vivo Wirksamkeit der verschiedenen Vakzinen: DNA vakzinierte Tiere entwickeln starke tumorantigenspezifische CTL-Antworten, wohingegen in MVA-vakzinierten Tieren überwiegend gegen virale Epitope gerichtete CD4 und CD8-T-Zellen detektiert wurden.<br /> <br /> Die Wirksamkeit der pCI-DNA-Vakzine spricht für die Weiterentwicklung in weiteren präklinischen Mausmodellen, beispielsweise unter Verwendung von MUC1 oder HLA-A2 transgenen Mäusen. Die Methoden zur Detektion Tumorantigen-spezifischer CTL in 96-Loch-Mikrotiterplatten können dabei zur systematischen Suche nach im Menschen immundominanten T-Zell-Epitopen im Muzin-Molekül genutzt werden. <br /> <br /> Der durchgeführte Vergleich der auf den Vektoren pCI und MVA basierenden Vakzinen und die Analyse neuerer Publikationen führen zu dem Ergebniss, daß vor allem DNA-Vakzinen in Zukunft eine wichtige Rolle bei der Entwicklung von aktiven Tumorimpfstoffen spielen werden. Rekombinante MVA-Viren, eventuell in Kombination mit DNA- oder anderen Vektoren, haben sich dagegen in zahlreichen Studien als wirksame Impfstoffe zur Kontrolle von durch Pathogene hervorgerufenen Infektionserkrankungen erwiesen. / In this study, tumor vaccines based on the plasmid pCI, the attenuated vaccinia virus strain modified vaccinia virus Ankara (MVA) and MVA-infected dendritic cells were constructed and characterized by sequencing, Western blot and flow cytometric analysis. The efficiency to induce tumor immunity in vivo was compared in several C57BL/6 mouse tumor models. Naked DNA Vaccination based on the eukaryotic expression vector pCI did induce very effective, antigen-specific and long-term protection against tumor cell lines expressing mucin, CEA or beta-Gal whereas MVA vaccination did not elicit protective immunity against Mucin or beta-Gal expressing tumors. MVA does infect human or murine in vitro generated dendritic cells very efficiently compared to other viral vectors, however expression levels of the inserted antigens in dendritic cells are significantly lower than in permissive host cells (chicken embryo fibroblasts). <br /> <br /> It could be shown that the effect of MVA infection on the maturation status of dendritic cells is similar to the effects described for dendritic cells infected with replication competent vaccinia strains. In addition it was shown that the upregulation of the important costimulatory molecule CD40 through LPS stimulation is strongly inhibited in MVA infected cells. During passage in tissue culture, MVA has accumulated a number of large deletions, including a number of immunomodulatory molecules and resulting in a strong attenuation. However the strong cytopathic effect on dendritic cells is maintained. <br /> <br /> The low level of expression and the effect on dendritic cell maturation may be responsible for the failure of MVA to induce tumor immunity through either cross presentation or direct infection of antigen presenting cells.<br /> <br /> To detect and quantify tumor-antigen-specific CTL a method based on intracellular IFN-gamma staining was modified and it could be shown that the cellular &ndash; but not the humoral &ndash; response does correlate with in vivo protection: DNA but not MVA vaccines do induce high levels of tumorantigen-specific CTL whereas MVA-vaccines do induce strong and long lasting CD4 and CD8-T-cell responses against vaccinia antigens. <br /> <br /> The excellent protection induced by pCI-DNA-vaccination in different tumor models does encourage us to further investigate the elicitation of tumor immunity in MUC1 or HLA-A2 transgenic mice. In mice transgenic for human MHC-I, the IFN-gamma staining protocol could be used to systematically screen for mucin T-cell epitopes that are relevant in humans.
50

Untersuchung von rekombinantem Vacciniavirus MVA zur Entwicklung von Impfstoffen gegen Infektionen mit Respiratorischen Synzytialviren

Süzer, Yasemin 12 June 2007 (has links)
In dieser Arbeit wurden Vektorimpfstoffe auf der Basis rekombinanter Vacciniaviren hinsichtlich ihrer Eignung zur Immunisierung gegen Infektionen mit Respiratorischen Synzytialviren (RSV) untersucht. Hierfür standen genetisches Material und Viruspräparationen des Respiratorischen Synzytialvirus des Rindes (BRSV, Stamm Odijk) sowie des Respiratorischen Synzytialvirus des Menschen (HRSV, Subtyp A2) sowie rekombinante Vacciniaviren MVA-HRSV-F bzw. MVA-HRSV-G zur Verfügung. Rekombinante MVA-Viren, welche die Gene der BRSV-Oberflächenproteine G und F (MVA-BRSV-F, MVA-BRSV-G, MVA-BRSV-Gneu), sowie Viren in welchen die Fremdgensequenzen durch Deletion wieder entfernt sind (Revertante Viren MVA-∆BRSV-F und MVA-∆BRSV-G), wurden gentechnologisch hergestellt. Alle rekombinanten MVA-Viren wurden molekular-virologisch charakterisiert und dienten zur Gewinnung und Prüfung von Testimpfstoffen im Tiermodell. Die Untersuchungen zeigen: 1. Alle neu konstruierten rekombinanten MVA-BRSV-Viren produzierten nach Infektion von Zellkulturen die erwünschten Zielantigene, die BRSV-Glykoproteine F und G. Für das durch MVA-Expression hergestellte BRSV-F-Glykoprotein konnte außerdem die biologische Funktionalität in einem Fusionstest in infizierten HeLa-Zellen nachgewiesen werden. 2. Die Charakterisierung der Genome aller MVA-BRSV- sowie MVA-HRSV-Vektorviren bestätigte die exakte Insertion der Fremdgensequenzen im anvisierten Genombereich und zeigte die genetische Stabilität der Virusisolate nach Passagierung. 3. Bei der Untersuchung des Wachstumsverhaltens von MVA-BRSV-F und MVA-BRSV-G zeigte sich die eingeschränkte Vermehrungsfähigkeit des Virus MVA-BRSV-G. Die Konstruktion und Untersuchung der revertanten Viren MVA-∆BRSV-F und MVA-∆BRSV-G belegte die Koproduktion des G-Proteins als Ursache des verminderten Replikationsvermögens. Dieser für ein mögliches Impfvirus erhebliche Nachteil konnte durch die Verwendung eines moderateren Vacciniavirus-Promotors zur Fremdgenexpression (rekombinantes Virus MVA-BRSV-Gneu) behoben werden. 4. Die Prüfung von Testimpfstoffen auf der Grundlage der rekombinanten MVA-HRSV-Viren in einem Maus-HRSV-Infektionsmodell zeigte, dass MVA-HRSV-Impfstoffe, im Gegensatz zu Impfstoffen aus mit Formalin-inaktiviertem HRSV, Immunantworten mit einem ausgewogenen TH1/TH2-assoziierten Zytokinprofil induzierten. Eine infolge von Immunisierung verstärkte Einwanderung eosinophiler Zellen (Marker für Immunpathogenese) in die Lungen HRSV-infizierter Tiere, konnte nach MVA-Impfung nicht beziehungsweise in nur sehr geringem Ausmaß festgestellt werden (OLSZEWSKA et al. 2004). 5. Wichtige erste Daten hinsichtlich der Verträglichkeit, Immunogenität und Schutzwirkung rekombinanter Impfstoffe auf der Basis von MVA-BRSV-F und MVA-BRSV-G konnten in einem Kälber BRSV-Infektionsmodell erhoben werden. Die zweimalige Immunisierung mit MVA-Impfstoff verlief bei allen Tieren ohne feststellbare Nebenwirkungen und die Anregung Vaccinia- bzw. BRSV-F-spezifischer Antikörper bestätigte die Immunogenität der Vektorvakzinen. Schließlich belegten klinische Daten, insbesondere die fehlende Fieberreaktion bei Impflingen nach BRSV-Belastungsinfektion, die Schutzwirkung der MVA-BRSV-Impfstoffe. Insgesamt unterstützen die erzielten Ergebnisse dieser Arbeiten die weitere präklinische und klinische Untersuchung von MVA-Vektorimpfstoffen zur wirksameren und sichereren Bekämpfung von Infektionen mit Respiratorischen Synzytialviren. / This study investigated vector vaccines based on recombinant vaccinia virus MVA for their suitability to immunize against infections with respiratory syncytial viruses. Genetic material and virus stocks of bovine respiratory syncytial virus (BRSV, Strain Odijk) and human respiratory syncytial virus (HRSV, Strain A2) and recombinant vaccinia viruses MVA-HRSV-F and MVA-HRSV-G were provided and used in this study. The project work included the genetical engineering of recombinant MVA expressing gene sequences encoding the BRSV surface proteins G and F (MVA-BRSV-F, MVA-BRSV-G, MVA-BRSV-Gneu) and the secondary generation of mutant viruses in which recombinant gene sequences have been removed (revertant viruses MVA-∆BRSV-F, MVA-∆BRSV-G). All recombinant MVA were carefully characterized in in vitro experiments and served for generation of vaccine preparations being tested in animal model systems. The investigations demonstrate: 1. All recombinant MVA-BRSV viruses produced the target antigens (BRSV-F and -G proteins) upon tissue culture infections. Functional activity of BRSV-F protein was demonstrated in a cell fusion assay using virus-infected HeLa cells. 2. The characterization of the genomes of all MVA recombinant viruses confirmed the correct insertion of foreign gene sequences into the target site of the MVA genome and demonstrated the genetic stability of the vector viruses upon tissue culture passage. 3. In vitro studies on virus growth revealed a reduced replicative capacity of the recombinant virus MVA-BRSV-G. Construction and growth analysis of revertant viruses MVA-∆BRSV-F and MVA-∆BRSV-G demonstrated that over expression of BRSV-G protein caused this replication deficiency which could be avoided by using a more moderate vaccinia virus promoter for transcriptional control of recombinant gene expression (recombinant virus MVA-BRSV-Gneu). 4. Upon characterization in a mouse-HRSV challenge model candidate vaccines based on recombinant MVA-HRSV viruses, in contrast to formalin inactivated HRSV, and induced a well balanced TH1 and TH2 cytokine profile. In addition, none of the MVA-HRSV-F vaccinated animals and only two of the MVA-HRSV-G immunized mice showed low-level eosinophilia in the lungs after HRSV challenge infection (OLSZEWSKA et al. 2004). 5. Vaccination experiments in the calf-BRSV challenge model generated first relevant data on safety, immunogenicity and protective capacity of MVA-BRSV recombinant vaccines. The repeated application of MVA vaccine was well tolerated by all vaccinated animals and the induction of vaccinia- and BRSV-F-specific antibody responses confirmed the immunogenicity of the MVA vector vaccines. Moreover, clinical data (lack of fever response in vaccines) suggested the protective capacity of MVA-BRSV immunization upon BRSV challenge. The obtained results from these studies clearly support further preclinical and clinical evaluation of recombinant MVA candidate vaccines to immunize against disease caused by RSV infections in cattle and humans.

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