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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.
81

Monitoring Bulbulderesi And Bakacak Landslides With Photogrammetric Techniques

Muratoglu, Bukay 01 June 2009 (has links) (PDF)
Every year, thousands of people all over the world are loosing their lives in natural disasters. As a second most widespread hazard, landslides are still a disaster problem for Turkey. The long-term monitoring studies of instability phenomena have a paramount importance for Turkey to reduce its both direct and indirect effects. The objective of this thesis is to monitor the activity of the B&uuml / lb&uuml / lderesi and Bakacak landslides in Asarsuyu Catchment for 42 years period by the digital aerial photogrammetric techniques while evaluating the possible use of archive aerial photography in such analysis. To achieve the purpose of the study an orthophoto map was generated by aerial photographs belonging to 1994 year. The orthophoto map was utilized as a base map for aerial photo interpretation of different sets of aerial photographs corresponding to 1952, 1972, 1984 and 1994 years. As a result of this, 4 landslide activity maps are obtained. In addition, the characteristics of these landslides are analyzed by utilizing digital elevation model (DEM) created from stereo photographs of 1994. As a result of the study, no considerable variation is detected in the position of main boundaries of B&uuml / lb&uuml / lderesi and Bakacak landslides except some minor differences. However, within the landslides many topographical changes were observed between 1952 and 1994 period. Based on the profiles from toe to crest of the B&uuml / lb&uuml / lderesi landslide, the approximate length was measured as 4773m whereas the approximate width was about 2614m. The areal extent was calculated as ~12km2 having an approximate slope gradient ranging between 10-15&deg / with local variations. On the other hand, the approximate length of Bakacak landslide was 4420m and the approximate width was 832m from toe to crest with an area of ~4km2 and with an approximate slope angle 9-14&deg / .
82

Slope Stability Assessment Along The Bursa-inegol-bozuyuk Road At Km: 72+000-72+200

Oztepe, Damla Gaye 01 September 2009 (has links) (PDF)
The purpose of this study is to determine the most suitable remediation technique via geotechnical assessment of the landslide that occurred during the construction of Bursa-ineg&ouml / l-Boz&uuml / y&uuml / k Road at KM: 72+000-72+200 in an ancient landslide area. For this purpose, the geotechnical parameters of the mobilized soil along the slide surface was determined by back analyses of the landslide at four profiles by utilizing the Slope/W software. The landslide was then modeled using coupled analyses (with the Seep/W and Slope/W softwares) along the most representative profile of the study area by considering the landslide mechanism, the parameters determined from the geotechnical investigations, the size of the landslide and the location of the slip circle. In addition, since the study area is located in a second degree earthquake hazard region, pseudo-static stability analyses using the Slope/W software were performed incorporating the earthquake potential. The most suitable slope remediation technique was determined to be a combination of surface and subsurface drainage, application of rock buttress at the toe of the slide and unloading of the landslide material. A static and dynamic analyses of the landslide was also performed through utilizing finite element analyses. The static analyses were calibrated using the inclinometer readings in the field. After obtaining a good agreement with the inclinometer readings and finite element analyses results, the dynamic analyses were performed using acceleration time histories, which were determined considering the seismic characteristics of the study area.
83

The religion of the landless : a sociology of the Babylonian Exile

Smith, Daniel L. January 1986 (has links)
In this study, the Babylonian Exile of the Jews is approached from the perspective of a sociological analysis of more recent historical cases of mass deportation and refugee behaviour. After this survey, four behaviour patterns are isolated that function as 'Mechanisms for Survival' for minorities in crisis and under domination in a foreign environment. These 'Mechanisms' include 1) Structural adaptation, 2) The rise of, and conflict between, new leaders. 35 new Folklore patterns, especially 'Hero' stories, and 4) adoption or elaboration of ritual as a means of boundary maintenance and identity preservation. These four mechanisms are then illustrated from Exilic texts of the Old Testament. The rise of Elders and the changing nature of the Bet Abot is seen as structural adaptation. The conflict of Jeremiah and Hananiah, and the advice of Jeremiah in his 'letter', is seen as the conflict of new leaders in crisis. The 'Diaspora Novella' is compared to Messianic expectation and especially to Suffering Servant to show how folklore can reflect social conditions and serve a function as 'hero stories'. Finally, the latest redactional layers of 'P' reveal concern for purity and separation that expressed itself in social isolationism and boundary maintenance, particularly in the dissolution of marriages with foreign wives. There is also a section on social conflict after the restoration, as a measure of the independent development of exilic social ideology and theology. The conclusion is that sociological analysis of the Exilic material reveals the exilic-post-exilic community exhibiting features of a minority group under stress, and the creative means by which that group responds by Mechanisms for Survival.
84

The perception of exile in Jeremiah and Ezekiel

Hamer, Penny January 2007 (has links)
No description available.
85

Distribution ecology of Palearctic migrants in the humid Guinea savannah in West Africa

Ivande, Samuel T. January 2015 (has links)
Declines in breeding populations of most migrants across much of the Palearctic have been linked to environmental conditions in their African non-breeding grounds. Studying winter distribution dynamics for these species is necessary to understand how factors in these areas may influence their overall population dynamics. This thesis explored in detail the distribution ecology of migrants in the Guinea savannah, the region from where wintering migrants currently show the greatest breeding population declines. In particular, I investigated some prevailing but hitherto little tested ecological hypothesis concerning impacts of geographical, vegetation and anthropogenic characteristics on the densities and winter distribution of migrants in Africa. Migrant distribution seemed to fit a pattern where decisions leading to winter habitat choice and association were hierarchical and jointly influenced by factors extrinsic and intrinsic to the habitats at large and finer scales respectively. Migrants were distributed in reasonable densities across a wide range of habitats. There was also evidence for an independent effect of latitude on densities and distribution, even after controlling for habitat characteristics. There was no evidence of large changes in latitudinal density patterns within a given winter season and site density patterns were generally consistent over the study duration. Migrants and taxonomically-related/ecologically similar Afrotropical residents showed similarities in habitat requirements and utilization, although migrants utilized habitats over a wider latitudinal range. Some migrants tended to show correspondence in site occurrence between consecutive winters but less so within a given winter season and there was an overall low transferability of habitat models for Palearctic migrants between sites in Nigeria. Collectively, the results describe distribution mechanisms typical for ecologically flexible species that can best be described as habitat generalists. As generalists, migrants are expected to show some resilience, especially in dealing with local and small scale changes on their wintering grounds such that these are unlikely to be the primary limiting factor in their population dynamics. However, the scale of ongoing habitat change across much of Africa is perhaps contributing to overcome the resilience engendered by their generalism. Conservation efforts for these mainly generalists species may therefore aim to preserve habitat on a large scale, perhaps through the promotion of sustainable land use practices.
86

Les effets des changements climatiques et des changements d’usages sur les oiseaux d’eau migrateurs : une approche mécaniste chez un oiseau emblématique, la Cigogne blanche / Effects of climate and land use changes on migratory waterbirds : a mechanistic approach in an emblematic bird, the White stork

Gadenne, Hélène 26 October 2012 (has links)
Comprendre les adaptations qui permettent aux espèces de vivre dans des environnements variables, temporellement et spatialement, est essentiel pour prédire la façon dont elles peuvent répondre aux changements globaux actuels et futurs. De nombreuses études à long terme ont montré que les fluctuations climatiques affectaient la dynamique des populations, mais l'influence relative des processus de sélection d'habitat et de densité-dépendance sur la sélection d'habitat est encore mal connue et expliquée. L'objectif de cette thèse est donc d'étudier, d'une part, par une approche corrélative, la sélection d'habitat densité-dépendante à quatre échelles spatiales différentes, chez une population de cigognes blanches (Ciconia ciconia) en augmentation; et d'autre part, par une approche mécaniste, d'étudier les effets relatifs du climat, de l'habitat et de l'expérience des reproducteurs en termes de fitness (nombre de jeunes produits, condition corporelle des jeunes et sexe-ratio) chez cet oiseau, suivi depuis 30 ans dans un milieu sensible, les zones humides de l'ouest de la France, en Charente-Maritime. Ce travail a contribué à identifier des mécanismes qui conduisent aux décisions de sélection d'habitat de nidification qui restaient encore mal compris, et appuie les travaux qui montrent que la dégradation des habitats par les activités humaines peut influer sur les décisions de sélection d'habitat. De plus, ces résultats apportent des informations essentielles à la compréhension des adaptations de cette population dans un environnement variable, ce qui permet de prédire plus efficacement le devenir de la population face aux changements environnementaux futurs. / Understanding adaptations that allow species to live in temporally and spatially variable environments is crucial to predict how species may respond to current and future global changes. Long-term studies have shown that climatic variations affect the dynamic of populations. However, the relative influence of habitat selection and density-dependence processes is still poorly understood and explained. The aim of this thesis is, firstly by a correlative approach, to investigate the density-dependent habitat selection at varying spatial scales in an increasing white stork (Ciconia ciconia) population. Secondly, by a mechanistic approach, we studied the relative effects of climate, habitat and breeder experience in terms of reproductive fitness (fledging success, body condition and sex ratio) in this population monitored for 30 years in a sensitive wetland in Charente-Maritime, western France. This work helped identifying the mechanisms that lead to nesting habitat selection. This work supports research showing that habitat degradation by human activities may affect habitat selection decisions. In addition, these results provide crucial information to understand the adaptations of this population in a changing environment, which allows predicting more efficiently the response of the population to future environmental changes.
87

With or without you : pair fidelity and divorce in monogamous birds

Culina, Antica January 2014 (has links)
The drivers of fidelity and divorce of pair-bonded individuals, along with their fitness consequences, are of great interest as they influence mating systems, population structure and productivity, and gene flow. Socially monogamous birds offer an ideal opportunity to study divorce since they show great variability in the extent to which pair bonds are maintained. However, there has been little consensus as to whether divorce is a behavioural adaptation to improve a mating situation, or a consequence of other processes. Moreover, the biological and ecological correlates of fidelity are difficult to address because previous work has been based on indirect and potentially biased methods. Finally, in terms of process, the link between the process of mate choice and subsequent mating decisions has been largely inaccessible to study. My doctoral thesis addressed these significant gaps in our understanding of cause, process and consequence in the formation and dissolution of pair bonds in socially monogamous birds. I accomplished this in three principal ways. First, I conducted a robust phylogenetic meta-analysis on 84 studies across 64 species to assess the existing empirical evidence that divorce in socially monogamous birds is adaptive (in terms of breeding success). This analysis revealed that divorce is, in general, adaptive as it is both triggered by relatively low breeding success and leads to improvement in success. Next, I developed a novel probabilistic multievent capture–mark–recapture framework that provides joint estimates of survival and fidelity while explicitly accounting for imperfect detection, capture heterogeneity, and uncertainty in pair status. By applying this model to breeding data on a wild great tit population I showed that birds that remain faithful to their partner exhibit higher survival rates and are more likely to remain faithful in the next breeding season than do birds that change partners. Subsequently, I confirmed the generality of a survival benefit by applying the model to breeding data on other tit populations. Then, by applying the model to data from a population of mute swans, I showed that fidelity decreases the likelihood of skipping breeding and mortality in this long-lived species, and that these effects depended on age, individual quality, and immigration status. Finally, I investigated how the timing of pair formation influences breeding success and divorce probability using five years of data on the over-winter social behaviour of great tits. I showed that early pair formation had a positive effect on fitness components, influencing the likelihood of divorce only indirectly, through breeding success. Further, my work revealed that males, but not females, with higher numbers of the female associates in winter, and males whose future breeding partners were ranked low amongst these, divorced more often. My research makes a significant contribution to our understanding of divorce and fidelity, and generates a number of important implications for future studies. First, my work establishes that divorce is adaptive for breeding success. Second, my results highlight that survival is an important (and likely, widespread) fitness consequence of pairing decisions. Third, I provide a novel statistically rigorous modelling framework for estimating fidelity-rates and testing hypothesis about fidelity that overcomes many of the inherent biases in traditional estimates. Fourth, it provides the first evidence for a selective advantage of early pair formation in wild, thus highlighting that there are benefits to pair familiarity that manifest via social associations of individuals prior to breeding. Finally, my work reveals the selective pressures operating via the social environment can ultimately influence the mating strategies individuals adopt.
88

Facteurs déterminant la longueur des télomères et implications dans les compromis évolutifs / Determinants of telomere length and implications in life history trade-offs

Reichert, Sophie 25 October 2013 (has links)
Une question fondamentale de la biologie évolutive porte sur la compréhension des mécanismes sous-tendant les processus évolutifs et l’évolution des compromis entre les traits d’histoire de vie. Parmi ces mécanismes, les télomères suscitent un intérêt particulier. Les télomères sont localisés à l’extrémité des chromosomes eucaryotes et participent à la sénescence cellulaire et au vieillissement des individus. La longueur des télomères est susceptible de donner des indications sur le mode de vie et l’état physiologique des organismes. Le but de cette thèse a été de comprendre quels sont les facteurs déterminant la longueur des télomères et leur implication dans les compromis évolutifs, ceci en établissant : si la taille des télomères est-elle héritable? Le taux de perte des télomères est-il affecté par des facteurs environnementaux? Quel lien entre les télomères, la maintenance individuelle et la qualité des individus? Il résulte de ce travail que la longueur des télomères est partiellement déterminée par les facteurs génétiques, elle semble aussi influencée par les facteurs environnementaux. En effet, le coût de la reproduction, ainsi que la modification des trajectoires de croissance, ont des effets néfastes sur la longueur des télomères. L’effet de la manipulation expérimentale de l’activité télomérase indique un lien entre les télomères et la maintenance individuelle, suggérant que les télomères sont susceptibles de donner des indications sur la qualité des individus. Ce travail de thèse montre que la dynamique des télomères est un mécanisme sous-jacent des compromis évolutifs, et présente un intérêt considérable pour la compréhension des processus évolutifs. / Evolutionary pathways through which life histories may have evolved are numerous. Consequently identifying the underlying mechanisms of those processes is crucial for our overall comprehension of the origin of life diversity. Thus, there is clearly a great potential in the study of repetitive DNA sequences that cap eukaryotic chromosomes, the telomeres. Telomeres are structures involved in cell senescence and determine the rate of ageing. They are thought to reflect more than just the effects ofage and to play an important role in linking life conditions and senescence. Indeed, telomeres could act as markers of life style and of past-historical levels of stress and inform on individuals’ current physiological quality. This thesis aims to determine whether telomeres could act as a mechanism underlying life history trade-offs by establishing the pattern of heritability of telomere length; characterising telomere length’s determinants; testing the nature of the relationship between telomerelength and individual maintenance, and ultimately with individual quality. The present work shows that telomere dynamics is determined by genetic factors, but is probably predominantly affected by lifestyle factors. As such, environmental conditions experienced during the growth period, as well as during adulthood (i.e. level of reproductive effort) have a strong impact on individuals’ telomere length. Experimental manipulation of telomerase activity showed that telomere length could be linked to individual maintenance and thus might be indicative of individual quality. Altogether, these results highlight that telomere dynamics might provide a functional link between life history traits.

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