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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.
1

Evolutionary dynamics of mimetic rings in heterogeneous ecological communities / Dinâmica evolutiva de anéis miméticos em comunidades ecológicas heterogêneas

Barros, Irina Birskis 28 June 2017 (has links)
Müllerian mimicry theory postulate that individuals of different species benefit from decreased per-capita attack risks by sharing similar warning signals. In species-rich mimetic assemblages, there is the formation of several distinct sympatric groups of species sharing the same warning signals, often color pattern, called mimetic rings. The coexistence of multiple rings seems paradoxical considering that selection among unpalatable species should favor convergence and thus reinforce a single color pattern. Different rings evolving in distinct habitats could explain the coexistence of multiple mimicry rings. However, the way species use the habitats might influence the emergence of multiple mimicry rings. We combined mathematical modeling and numerical simulations to explore how habitat heterogeneity, abiotic selection and habitat generalist species influence the formation of mimicry rings in a community. We showed that distinct selection pressures, derived from habitat heterogeneity, favored the formation of distinctive mimicry rings. Nevertheless, just the co-existence of species was enough to drive the emergence of the rings. Simulations in which there was just biotic or abiotic selection, time for convergence was faster than when both sources of selection acted together, suggesting conflicting selective pressures exerted by environment and co-existing species. In the presence of species that was habitat generalist, species converged to similar trait values, decreasing the distinctiveness of mimicry rings. A unique mimicry ring was formed if the different habitats optima in the community were very similar or when most species were habitat generalists. Our results suggest that multiple sympatric mimicry rings are formed by a complex interplay between abiotic and biotic selection and is only possible in groups of animals in which local species composition is strongly affected by habitat heterogeneity such as butterflies / No mimetismo Mülleriano, indivíduos de diferentes espécies, ao compartilharem um mesmo sinal de advertência, beneficiam-se mutuamente devido ao menor risco de predação. Em comunidades ricas em mímicos há a formação de grupos simpátricos de espécies denominados anéis miméticos, que compartilham os mesmos sinais de advertência, como por exemplo padrões de coloração. A coexistência de anéis miméticos parece paradoxal, uma vez que, em teoria, a seleção favoreceria a convergência das espécies impalatáveis e, portanto, geraria um único padrão de cor. A evolução de diferentes anéis miméticos em habitats distintos poderia explicar a coexistência desses anéis em uma comunidade. No entanto, a maneira como as espécies utilizam esses habitats talvez influencie também a emergência dos múltiplos anéis miméticos. Utilizamos modelos matemáticos e simulações computacionais para melhor compreender como a heterogeneidade de habitats, a seleção ambiental e espécies generalistas de habitat influenciam a formação de anéis miméticos em uma comunidade. Demonstramos que diferentes pressões seletivas, derivadas de uma heterogeneidade de habitats, podem favorecer a formação de anéis miméticos. Porém, a simples coexistência das espécies é suficiente para a emergência de anéis. Em simulações nas quais só havia seleção imposta por espécies impalatáveis ou pelo ambiente, o tempo de convergência foi mais rápido do que quando as duas forças seletivas atuavam juntas. Isto demonstra que provavelmente há conflito entre a seleção biótica e abiótica, não favorecendo o mesmo ótimo fenotípico. A presença de uma espécie generalista de habitat favoreceu a convergência de espécies para um valor fenotípico similar, diminuindo a distinção entre os anéis. Um único anel foi formado quando os diferentes fenótipos favorecidos pela seleção imposta pelo ambiente eram muito similares entre habitats, ou quando muitas espécies eram generalistas de habitat. Nosso trabalho sugere que múltiplos anéis miméticos simpátricos são formados por uma complexa interação entre seleção biótica e abiótica e que só são possíveis em grupos no qual a diversidade é estruturada em pequenas escalas espaciais, como borboletas
2

Evolutionary dynamics of mimetic rings in heterogeneous ecological communities / Dinâmica evolutiva de anéis miméticos em comunidades ecológicas heterogêneas

Irina Birskis Barros 28 June 2017 (has links)
Müllerian mimicry theory postulate that individuals of different species benefit from decreased per-capita attack risks by sharing similar warning signals. In species-rich mimetic assemblages, there is the formation of several distinct sympatric groups of species sharing the same warning signals, often color pattern, called mimetic rings. The coexistence of multiple rings seems paradoxical considering that selection among unpalatable species should favor convergence and thus reinforce a single color pattern. Different rings evolving in distinct habitats could explain the coexistence of multiple mimicry rings. However, the way species use the habitats might influence the emergence of multiple mimicry rings. We combined mathematical modeling and numerical simulations to explore how habitat heterogeneity, abiotic selection and habitat generalist species influence the formation of mimicry rings in a community. We showed that distinct selection pressures, derived from habitat heterogeneity, favored the formation of distinctive mimicry rings. Nevertheless, just the co-existence of species was enough to drive the emergence of the rings. Simulations in which there was just biotic or abiotic selection, time for convergence was faster than when both sources of selection acted together, suggesting conflicting selective pressures exerted by environment and co-existing species. In the presence of species that was habitat generalist, species converged to similar trait values, decreasing the distinctiveness of mimicry rings. A unique mimicry ring was formed if the different habitats optima in the community were very similar or when most species were habitat generalists. Our results suggest that multiple sympatric mimicry rings are formed by a complex interplay between abiotic and biotic selection and is only possible in groups of animals in which local species composition is strongly affected by habitat heterogeneity such as butterflies / No mimetismo Mülleriano, indivíduos de diferentes espécies, ao compartilharem um mesmo sinal de advertência, beneficiam-se mutuamente devido ao menor risco de predação. Em comunidades ricas em mímicos há a formação de grupos simpátricos de espécies denominados anéis miméticos, que compartilham os mesmos sinais de advertência, como por exemplo padrões de coloração. A coexistência de anéis miméticos parece paradoxal, uma vez que, em teoria, a seleção favoreceria a convergência das espécies impalatáveis e, portanto, geraria um único padrão de cor. A evolução de diferentes anéis miméticos em habitats distintos poderia explicar a coexistência desses anéis em uma comunidade. No entanto, a maneira como as espécies utilizam esses habitats talvez influencie também a emergência dos múltiplos anéis miméticos. Utilizamos modelos matemáticos e simulações computacionais para melhor compreender como a heterogeneidade de habitats, a seleção ambiental e espécies generalistas de habitat influenciam a formação de anéis miméticos em uma comunidade. Demonstramos que diferentes pressões seletivas, derivadas de uma heterogeneidade de habitats, podem favorecer a formação de anéis miméticos. Porém, a simples coexistência das espécies é suficiente para a emergência de anéis. Em simulações nas quais só havia seleção imposta por espécies impalatáveis ou pelo ambiente, o tempo de convergência foi mais rápido do que quando as duas forças seletivas atuavam juntas. Isto demonstra que provavelmente há conflito entre a seleção biótica e abiótica, não favorecendo o mesmo ótimo fenotípico. A presença de uma espécie generalista de habitat favoreceu a convergência de espécies para um valor fenotípico similar, diminuindo a distinção entre os anéis. Um único anel foi formado quando os diferentes fenótipos favorecidos pela seleção imposta pelo ambiente eram muito similares entre habitats, ou quando muitas espécies eram generalistas de habitat. Nosso trabalho sugere que múltiplos anéis miméticos simpátricos são formados por uma complexa interação entre seleção biótica e abiótica e que só são possíveis em grupos no qual a diversidade é estruturada em pequenas escalas espaciais, como borboletas
3

Ecevit&#039 / s Conception Of Nationalism: A Unique Position Or A Syncretic Vision?

Konuralp, Emrah 01 December 2009 (has links) (PDF)
This thesis is the analysis of B&uuml / lent Ecevit&rsquo / s conception of nationalism. It also involves a review of contemporary theories of nationalism and academic works on nationalism in Turkey. The thesis is organised as analysis of Ecevit&rsquo / s nationalism within time intervals in order to elaborate on the consistency of his conception nationalism along his long political life. The major source for analysis is Ecevit&rsquo / s speeches in the Grand National Assembly of Turkey, his books, articles and declarations. In this sense, Ecevit&rsquo / s meaning giving process to nationalism is researched.
4

Geological, Hydrogeological And Geochemical Analyses Of The Geothermal Systems In The Buyuk Menderes Graben

Guducu, Hatice 01 November 2012 (has links) (PDF)
Geothermal reservoirs have become very popular in the last decades due to their renewable energy contents. Turkey has a high geothermal energy potential / especially Western Anatolia is a promising region in terms of its highest energy. B&uuml / y&uuml / k Menderes Graben system is a tectonically active extensional region and is undergoing a N&ndash / S extension leading to form geothermal fields in the graben. In the last decade, geothermal exploration, investigations and investments have been increased rapidly through the law related to geothermal energy assigned. The aim of this study is to analyze the geothermal fields located in the graben system in order to investigate their geological, hydrogeological and geochemical features and reservoir characteristics. A data set is compiled from the accessible archives, published papers and documents and several variables have been searched at every field in the graben. The variables include the fluid temperature, the distance to sea, the depth to the reservoir, the reservoir lithology, the chemical constituents, etc. In view of these variables the fields are compared and constrasted and their common characterisrics have been noted. Interpretation of the data set reveals that the fields have some common features and characters however some fields have got notable differences.
5

Salih Zeki&#039 / s Darulfunun Konferanslari And His Treatment Of The Discovery Of Non-euclidean Geometries

Kadioglu, Dilek 01 February 2013 (has links) (PDF)
This thesis examines Dar&uuml / lf&uuml / nun Konferanslari which consists of a series of lectures that were delivered by Salih Zeki in 1914 &ndash / 1915 in Ottoman State. These lectures were on geometry, its history and especially on the discovery of non-Euclidean geometries. And the purpose of this thesis is to propose the sufficiency and the legitimacy of these lectures as an account on the history of geometry. As a preliminary to analyzing Salih Zeki&rsquo / s lectures, different views on geometry&rsquo / s history and progress will be analyzed and compared. The results of this comparison will be the guide by means of which Dar&uuml / lf&uuml / nun Konferanslari will be examined. This thesis also serves as a source that makes Salih Zeki&rsquo / s ideas accessible, by presenting an English summary of his lectures which were originally published in Ottoman Turkish.
6

A Critical Assessment For Reuse Of Traditional Dwellings As Boutique Hotels In Urgup

Can, Sukran Gunes 01 May 2007 (has links) (PDF)
Traditional dwellings have been exposed to environmental factors due to the increasing concentration in urban areas or reusing the dwellings for a different function that brings more profit. Tourism is one of the most important reasons for this transformation. Cappadocia is one of the regions where the transformation of historical structures into tourism facilities is common. In the last 5-10 years the concept of tourism and hotel management has changed and dwellings themselves were transformed to hotels and were called Boutique Hotels. And this transformation is mostly seen in &Uuml / rg&uuml / p. However, some problems are encountered in the transformation of traditional dwellings into Boutique Hotels. These problems are concerned with the difficulties experienced in interventions to the dwellings, positive and negative affects on environment and the legal problems pertaining the project, implementation and certification procedures. This thesis aims to question the harmony between the transformation in &Uuml / rg&uuml / p and the functional, physical, social and cultural aspects of the traditionaldwellings in &Uuml / rg&uuml / p, to assess the the implementations and their relations with environment relationships. In addition to this, taking the example of &Uuml / rg&uuml / p as a starting point, this thesis aims to discuss the relations between cultural identity and tourism, the positive and negative effects of tourism on traditional structure, and the balance between conservation and tourism. Taking into consideration the deficiencies in the legal definition and management criteria of Boutique Hotels, which are gradually becoming common, the discussion of the definition of Boutique Hotel is one of the important aims of this thesis.
7

Urban Transformation Of Ottoman Port Cities In The Nineteenth Century: Change From Ottoman Beirut To French Mandatory Beirut

Kihtir Ozturk, Pelin 01 September 2006 (has links) (PDF)
This thesis attempts to give the increasing importance of Ottoman port cities in the urban hierarchy during the nineteenth century and analyzes the urban transformation of these cities under the forces of changing administrative and socio-economic structure of the empire. The impact of European economic penetration and Ottoman Tanzimat Reforms were indicated as major causes for this changing structure. Beirut, being one of the major port cities of the Ottoman Empire is studied as a case study. The changing administrative and socio-economic structure of the Empire created an urban transformation which changed the city to a cosmopolitan trade capital from a small fortified port city.
8

Late Ottoman Resort Houses In Istanbul: Buyukada And Kadikoy

Koseoglu, Irmak 01 February 2013 (has links) (PDF)
The thesis aims to study the development of late 19th and early 20th century domestic architecture in B&uuml / y&uuml / kada and Kadik&ouml / y as new resort districts of Istanbul. The urban development of Istanbul and B&uuml / y&uuml / kada is introduced as a basis to discuss the architectural context and domestic life. The discussion centers on the emergence of concept of &lsquo / resort houses&rsquo / as a new dwelling type in Istanbul in the late Ottoman period. Selected case studies are described and compared to illustrate how such houses were conceptualized, built and utilized.
9

Viable Higher Derivative Theories

Ozonder, Sener 01 July 2007 (has links) (PDF)
In this thesis, higher derivative theories are investigated. Ostrogradskian instability of higher derivative theories is examined both at the classical and quantum levels. It is shown that avoiding the instability in nondegenerate higher derivative theories is impossible. Moreover, the degenerate model of relativistic particle with a curvature term is studied as a viable higher derivative theory. Most of the work we present here is not original. We give a review of the literature and compile various detached works that already exist.
10

Identifying The Values Of Kucukbahce Village Through Its Architecture And Collective Memory

Cocen, Oget Nevin 01 December 2007 (has links) (PDF)
Karaburun Peninsula is one of the coastal peripheral areas of Izmir where social, cultural and economicaal effects of Izmir on a rural environment can be seen. Karaburun, with a historical background that can be dated back as much as Izmir&amp / #8217 / s, had continuously been inhabited and considered as a strategic place. However, it was never got densely populated and urbanized but had kept constant in its modest rural life. Complying with the context of the Aegean coast, it was compromised of villages with mutually living societies of Turkish and Rum people. Turkish people were the prevailing settlers on the peninsula and owners of most of the properties while Rums with many other poor Turkish people were the working group to earn their lives. However, this harmonious living in Ottoman villages had to last with the population exchange between the Rums in the peninsula and the Muslims in Aegean island and Balkans, as a consequence of Lausanne Treaty that took place in 1923. 1922 was a turning point in Karaburun peninsula&amp / #8217 / s life. It became a purely Turkish peninsula and with less population and idly in socioeconomic life compared to its past. Today, Karaburun consists of thirteen villages, which carry footprints of Ottoman legacy in varying levels of perception and ways of exposition. Unfortunately, most of the fairly populated villages&amp / #8217 / historic contexts are almost demolished. K&uuml / &ccedil / &uuml / kbah&ccedil / e is one of these historic villages of the peninsula which is almost abandoned. However, it is a village, in which cultural, social and physical values of Ottoman period can still be perceived and their change can be followed. The study was conducted to identify the architectural characteristics, on the Aegean coast, of late Ottoman village, K&uuml / &ccedil / &uuml / kbah&ccedil / e while understanding its rural life and determining its cultural, social and physical values. The thesis aims to reconstruct and visualize the rural life between 1850s and 1922 and physical environment of the village via juxtaposing some of the oral historic documents and the givens of the built environment. Thus, it conceives information to understand how change in social and cultural values influence and are reflected in the built environment of the historic village and establish knowledge on how this historic village can continue its living in contemporary life while conserving its inherited values from Ottoman period. On the whole, a source of reference on K&uuml / &ccedil / &uuml / kbah&ccedil / e, where the collective memory of its inhabitants and its architecture are explained as the main sources for its description, is achieved. Thus, a base for further studies on the conservation of K&uuml / &ccedil / &uuml / kbah&ccedil / e is established where politics of conservation strategies, principles for interventions and refunctioning of the village are determined. Accordingly, a conservation project for K&uuml / &ccedil / &uuml / kbah&ccedil / e is decided to base on the three inputs of its current situation as: break, continuity and change. Hence, agro tourism is proposed as the new function of the village where continuity of the economic activities and social life will be sustained, the break in the life and development of the built environment will be recovered and the population characteristics and construction activities that are already in change will be defined to change in a conservation concsiously manner. Regarding the whole, this thesis contains necessary and satisfying information for a study of the possibilities on the re-functioning of the village. Thus, the decision on the function of the village and the structure of a conservation project has to be given by collaboration of a larger group of specialists building on the knowledge secured by this thesis.

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