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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

Civic Poetics: A Criminal's Relations With the Divine as Mediated by the Polis- A Polis' Relations with the Divine as Mediated by its Criminals

Baumunk, Jason H. 06 May 2012 (has links)
A criminal is thrown from a high cliff into the sea. He has been covered in feathers, live birds attached to him to slow his fall. Fishermen wait below, hopeful of being able to carry him safely away. The people are punishing the criminal with death, yet simultaneously rooting for his survival. This startling image from Strabo, with its delicious ironic tension, is the center‐piece of “Civic Poetics.” The thesis consists of a cycle of poems imagining life in a city where this bizarre ritual is performed, coupled with a number of essays written for several Religious Studies courses on related themes. The interplay of poetry and essay aims to illuminate the experience of my own journey from criminal outsider to re‐integrated citizen. The lenses of (1) my own experiences in 21st century Atlanta and (2) poetic imaginative reconstruction of this ancient ritual reveal a startling picture: a criminal’s relations with the divine, as mediated by his state, and a state’s relations with the divine as mediated by its criminals.
2

Civic Poetics: A Criminal's Relations With the Divine as Mediated by the Polis- A Polis' Relations with the Divine as Mediated by its Criminals

Baumunk, Jason H. 06 May 2012 (has links)
A criminal is thrown from a high cliff into the sea. He has been covered in feathers, live birds attached to him to slow his fall. Fishermen wait below, hopeful of being able to carry him safely away. The people are punishing the criminal with death, yet simultaneously rooting for his survival. This startling image from Strabo, with its delicious ironic tension, is the center‐piece of “Civic Poetics.” The thesis consists of a cycle of poems imagining life in a city where this bizarre ritual is performed, coupled with a number of essays written for several Religious Studies courses on related themes. The interplay of poetry and essay aims to illuminate the experience of my own journey from criminal outsider to re‐integrated citizen. The lenses of (1) my own experiences in 21st century Atlanta and (2) poetic imaginative reconstruction of this ancient ritual reveal a startling picture: a criminal’s relations with the divine, as mediated by his state, and a state’s relations with the divine as mediated by its criminals.
3

Spring distribution and habitat use of belugas (Delphinapterus leucas) in the eastern Beaufort Sea

Asselin, Natalie Claudette 17 January 2011 (has links)
An understanding of the adaptability of belugas (Delphinapterus leucas) to changing ice-conditions is required to interpret and predict possible changes in habitat selection in response to projected loss of sea ice throughout the circumpolar Arctic. Beluga spring distribution in the eastern Beaufort Sea was described by analyzing observations from aerial surveys conducted from 1975 to 1979. Repeated surveys along the Franklin Bay fast-ice edge in June 2008 were used to study the distribution and behaviour of belugas and bowheads. Despite inter-annual variability in ice extent, belugas consistently selected areas with water depths of 200-500 m, heavy ice concentrations (8/10 to 10/10) and seafloor slope ≥0.5 degrees in spring 1975 to 1979. While predator avoidance may partially explain the observed distribution, foraging success likely has more influence on beluga habitat selection in the spring. In ice-covered offshore regions, belugas may be engaged in under-ice and deep water foraging on Arctic cod (Boreogadus saida). In lighter ice years, belugas may expand their distribution and shift shoreward to take advantage of high prey densities along fast-ice edges. Both belugas and bowheads appeared to be feeding along the Franklin Bay ice edge in June 2008. More research is required to examine and compare possible changes in distribution since the late 1970s and to investigate the factors driving the patterns described.
4

Spring distribution and habitat use of belugas (Delphinapterus leucas) in the eastern Beaufort Sea

Asselin, Natalie Claudette 17 January 2011 (has links)
An understanding of the adaptability of belugas (Delphinapterus leucas) to changing ice-conditions is required to interpret and predict possible changes in habitat selection in response to projected loss of sea ice throughout the circumpolar Arctic. Beluga spring distribution in the eastern Beaufort Sea was described by analyzing observations from aerial surveys conducted from 1975 to 1979. Repeated surveys along the Franklin Bay fast-ice edge in June 2008 were used to study the distribution and behaviour of belugas and bowheads. Despite inter-annual variability in ice extent, belugas consistently selected areas with water depths of 200-500 m, heavy ice concentrations (8/10 to 10/10) and seafloor slope ≥0.5 degrees in spring 1975 to 1979. While predator avoidance may partially explain the observed distribution, foraging success likely has more influence on beluga habitat selection in the spring. In ice-covered offshore regions, belugas may be engaged in under-ice and deep water foraging on Arctic cod (Boreogadus saida). In lighter ice years, belugas may expand their distribution and shift shoreward to take advantage of high prey densities along fast-ice edges. Both belugas and bowheads appeared to be feeding along the Franklin Bay ice edge in June 2008. More research is required to examine and compare possible changes in distribution since the late 1970s and to investigate the factors driving the patterns described.
5

Population Genetic Structure of Beluga Whales Delphinapterus leucus Mitochondrial DNA Sequence Variation Within and Among North American Populations / Population Genetic Structure of Beluga Whales

Brennin, Ree January 1992 (has links)
Beluga whales are migratory over much of their range, congregating in small groups around shallow river estuaries in summer, and overwintering in large groups in areas with reliable open water. This complicates management issues because it is unclear if belugas from the common wintering ground represent one large group with exchange of individuals, or if each summer estuarine concentration should be managed as a separate stock. To examine the genetic structuring, we analyzed variation in mitochondrial DNA (mtDNA) restriction sites among 101 beluga whales from 10 regions across North America, including Greenland. Using 11 restriction enzymes, 9 haplotypes were identified among 71 whales. The remaining 30 whales were tested with only the six restriction enzymes found to identify polymorphisms. We found a marked segregation of divergent haplotypes for both sexes between eastern and western Hudson Bay. Haplotype 1 was found in 19 out of 21 animals on the east coast, while haplotype 5 was found in 18 out of 20 animals on the west coast. Sequence divergence among the 71 belugas was estimated to be 2.03%. Haplotypes fell into two major phylogenetic groups, labelled lineage I and II. Lineage I haplotypes occurred primarily in the St. Lawrence Estuary and the eastern Hudson Bay. Lineage II haplotypes occurred primarily along the western Hudson Bay, Southern Baffin Island, western Greenland, the Canadian high arctic, and the Beaufort Sea. These findings support the hypothesis that belugas exhibit maternally directed philopatry to summering grounds, and are consistent with the hypothesis that after deglaciation, the arctic was recolonized by at least two stocks of belugas divergent in their mtDNA, possibly representing Atlantic and Pacific stocks. / Thesis / Master of Science (MS)
6

Écologie comportementale des requins bouledogue (Carcharhinus leucas) sur les côtes de La Réunion : application à un modèle de gestion du « risque requin » / Behavioral ecology of bullsharks (Carcharhinus leucas) along the coasts of Reunion Island : application to a shark risk management model

Blaison, Antonin 29 June 2017 (has links)
Entre 2011 et avril 2017, La Réunion a connu 22 attaques de requin, dont 9 mortelles. Cette intensification des Conflits Hommes-Requins (CHR) à La Réunion a donné naissance au programme de recherche, CHARC, dont le but est de mieux comprendre la biologie et l'écologie des requins bouledogue (Carcharhinus leucas). C'est dans ce contexte et au sein de ce programme que s'est réalisé ce projet de thèse. Représentant la première étude de ce type sur cette espèce, l'objectif principal de la thèse a été de déterminer les caractéristiques et les particularités de la population observée, de délimiter son habitat et ses micro-habitats, d'en étudier son occupation spatiale et temporelle et de comprendre le rôle de ces micro-habitats dans le cycle de vie de l'espèce. Pour atteindre ces objectifs, l'étude repose sur une campagne de marquage et le suivi acoustique passif des 35 requins bouledogue le long de la côte ouest pendant 18 mois. La quasi-totalité des requins marqués sont des adultes de grande taille, avec un sex-ratio en faveur des femelles. De part ces caractéristiques, cette population de requins bouledogue se distingue de la majorité des autres populations observées à travers le monde.L'occupation spatiale et temporelle des requins n'était pas homogène, avec l'utilisation de zones préférentielles et une forte saisonnalité. On observe également une variabilité individuelle, influencée par la taille et le sexe des individus : les jeunes adultes, des deux sexes, sont essentiellement localisés dans le sud de la zone, au cours de deux pics de présence, un hivernal et un estival. A l'inverse, les grandes femelles sont majoritairement localisées dans le nord de la zone, avec un pic de présence hivernal. Les grands mâles sont peu présents et essentiellement localisés dans le nord et à l'extrémité sud de la zone d’étude au cours de la période creuse de juillet à octobre. Indépendamment du sexe et de la taille des individus, les zones préférentielles sont utilisées comme zone de repos sur l'ensemble des périodes nycthémérale et comme zone de chasse nocturne. Certaines zones préférentielles pourraient également jouer un rôle dans la reproduction. Les zones secondaires représentent principalement des zones de passages entre les zones préférentielles ou des zones de chasse nocturne secondaire. Si l'ensemble de ces résultats devra être confirmé par d'autres études à plus grande échelle spatio-temporelle, il montre toute la complexité du comportement et des déplacements des requins bouledogue dans les eaux réunionnaises. Cette thèse ouvre de nouvelles perspectives d'étude, notamment sur l'influence des facteurs environnementaux dans l'occupation spatio-temporelle des requins ou sur l'existence de phénomènes liés à la reproduction comme la philopatrie et la polyandrie. / A serie of 22 shark attacks occurred at Reunion Island between 2011 and April 2017, causing nine deaths. Following the rise of the Human Shark Conflict (HSC), a research program, CHARC, was launched to better understand the biology and ecology of bullshark (Carcharhinus leucas). This thesis was carried out within this program. Representing the firststudy on this specie at Reunion Island, the main objective was to determine characteristics of the observed population, to define it habitat and its micro-habitats, to study its spatial and temporal occupation and to understand the role of these micro-habitats in the life cycle of the specie. This study is based on a tagging campaign and passive acoustic telemetry of 35 bullsharks along the west coast for 18 months. Almost all tagged sharks are adults, large in size and with a sex ratio in favor of females. Base of these characteristics, this bullshark population differs from the majority of other observed populations throughout the world. The spatial and temporal occupation was not homogeneous, with use of preferential areas and strong seasonality. Individual variability is also observed, influenced by size and sex: young adults, of both sexes, are mainly located in the southern part of the study area, during two peaks of presence, one in winter and one in summer. Conversely, large females are mostly located in the north of study area, with a peak of presence in winter. Large males are rarely present and mostly located at the ends of the north and south of the study area from July to October. Apart from sex and size of individuals, preferential areas are used as resting areas, during all nycthemeral periods and as hunting area at night. Some preferential areas may also play a role in breeding behaviour. The secondary areas are mainly used to move from a preferential area to another or as secondary hunting area at night. If all these results have to be confirmed by larger-scale spatio-temporal studies, it put in light the complexity of bullshark behavior and movements along the coasts of Reunion Island. This thesis gives perspectives for new studies, including studies on environmental factors influence on spatio-temporal occupation of sharks or on phenomena related to reproduction such as philopatry and polyandry.
7

Den smältande polarisens effekt på de endemiska valarna i Arktis

Larsson, Hanna January 2014 (has links)
Klimatförändringarna har en stor påverkan på de arktiska valarna grönlandsval (Balaena mysticetus), vitval (Delphinapterus leucas) och narval (Monodon monoceros), mer än vad som tros vid en första tanke. I dagsläget får dessa valar utstå stora utmaningar som troligenkan komma att förvärras i framtiden om inte isens smältande kan bromsas. En del av utmaningarna innebär att valarna måste genomgå stora förändringar för att överleva, vilket innebär att deras förmåga att anpassa sig spelar en stor roll. Människans jakt på valen har alltid varit ett stort problem för de arktiska valarna, tack vare restriktioner om fångstkvoter och vem som får jaga val ser framtiden ljusare ut i alla fall för grönlandsvalen och vitvalen. För narvalen ser det dock inte lika ljust ut eftersom det är en art som är känsligare än många andra arktiska arter för effekterna som den globala uppvärmningen har på den arktiska miljön. I dagsläget har en del effekter på valarna blivit synliga såsom ändrade migrationsvanor och ökad predation. På grund av bristande data från perioden innan klimatförändringarna är detsvårt att dra konkreta slutsatser, därför fokuserar mycket forskning på att förutse vad som kommer att ske i framtiden. Fokus på framtiden är viktigt eftersom det som sker idag redan är försent att göra någonting åt, det vi kan göra är att se till att det inte blir ännu värre. Den smältande isens effekter är svåra att skilja på då de överlappar en del, till exempel leder tillgången på föda till förändringar i habitat. Man har i dagsläget sett små skillnader i tillgång på föda, beståndet av istorsken har minskat, eftersom det är en viktig föda för de arktiska valarna kan det ha en effekt. En minskning av en viss typ av plankton har också observerats och eftersom ingen ersättande art har setts kommer detta få effekter på näringsväven i de arktiska haven och därmed alla arter som lever där inklusive de arktiska valarna. I framtiden tror man att primärproduktionen kommer att öka på grund av den höjda vattentemperaturen och den ökande ytan med öppet vatten, detta kommer eventuellt ha en positiv effekt på de arktiska valarna.
8

THE BULL SHARK (CARCHARHINUS LEUCAS) AS A SENTINEL SPECIES FOR HARMFUL ALGAL BLOOM TOXINS IN THE INDIAN RIVER LAGOON, FLORIDA

Unknown Date (has links)
This study explored spatiotemporal patterns in movement, diet, and baseline phycotoxin concentrations in immature bull sharks (Carcharhinus leucas) of the Indian River Lagoon (IRL), an estuary of national significance that has been considerably impacted by multiple toxic harmful algal blooms (HABs). Long-term spatial use of the system was assessed for 29 acoustically tagged sharks over a 4 year period (2017–2020). Tissue samples for diet and toxin analysis were collected from a separate cohort of 50 individuals between 2018 and 2020. UPLC-MS/MS was used to screen tissues for 14 algal toxins. Young bull sharks were found to be mainly piscivorous and displayed high residency to the IRL as well as to specific regions of the IRL, with small activity spaces. Multiple phycotoxins were detected in screened tissues, indicating that young bull sharks in the IRL may be compromised by trophic transfer of HABs while they reside in this important nursery. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2021. / FAU Electronic Theses and Dissertations Collection
9

Use of Molecular Tools on Surveys of Genetic Variation and Population Structure in Three Species of Sharks

Castro, Andrey Leonardo F 01 April 2009 (has links)
Molecular tools, such as sequencing of the mitochondrial DNA Control Region (CR) and genotyping of highly variable nuclear microsatellites were applied to survey the genetic diversity, population structure and phylogeography of three shark species: the whale shark, Rhincodon typus; the bull shark, Carcharhinus leucas; and the nurse shark, Ginglymostoma cirratum. The highly migratory and pelagic whale shark exhibited the largest length variation yet reported for an elasmobranch CR (1143–1332 bp), and high haplotype (h = 0.974 ± 0.008) and nucleotide diversities(π = 0.011 ± 0.006). No geographical clustering of lineages was observed and the most common haplotype was distributed globally. The haplotype frequency, however, differed between the Atlantic and Indo-Pacific populations(AMOVA, ΦST = 0.107, P < 0.001). For the bull shark, both mtDNA CR and five microsatellite loci were surveyed for animals from the Gulf of Mexico, the East coast of Florida and the Brazilian coast. Strong genetic structure was observed between theBrazilian and all northern populations for the CR (ΦST > 0.8, P < 0.001), but not for the nuclear microsatellite. The results here presented are congruent with restricted maternal gene flow between populations as a consequence of female nursery site fidelity. The philopatric tendencies as well as the relatively low levels of genetic diversity raises concerns about the conservation of this species. Finally, for the western Atlantic nurse sharks the genetic diversity estimated in a 1,166 bp fragment of the mtDNA comprising partial cytochrome b, tRNAPro, tRNAThr, and partial CR was the second smallest ever recorded for sharks (h = 0.45 ± 0.04; π = 0.0004 ± 0.0004). The data indicated moderate but significant genetic structure with the mtDNA marker (ΦST = 0.22, P<0.05) and no substantial structure in eight microsatellite loci analyzed. A population bottleneck as recent as the lower Pleistocene might have eroded the nurse shark genetic diversity and also contributed to its relatively lower population structure. The data also indicated that dispersal rather than vicariance better explains the Atlantic distribution of nurse shark, and that the Pacific nurse shark might be a cryptic sister species to Ginglymostoma cirratum.
10

Indices de condition corporelle chez le béluga du Saint-Laurent : utilisation rétrospective de données morphologiques recueillies lors de nécropsies

Larrat, Sylvain 10 1900 (has links)
L’évaluation de la condition corporelle des carcasses des bélugas du Saint-Laurent contribue au diagnostic de cause de mortalité du pathologiste. La méthode actuelle repose sur une évaluation visuelle subjective. Notre projet visait à chercher un outil objectif d’évaluation de la condition corporelle. L’indice de masse mise à l’échelle (M̂ i) est objectif puisqu’il est calculé à partir de la masse et de la taille de chaque individu. M̂ i doit être calculé avec des constantes différentes pour les bélugas mesurant plus ou moins de 290 cm. Il produit des résultats en accord avec l’évaluation visuelle. Comme il est parfois logistiquement impossible de peser un béluga, nous avons évalué des indices basés sur d’autres mesures morphométriques. Les indices basés sur la circonférence à hauteur de l’anus pour les bélugas de moins de 290 cm et la circonférence maximale pour ceux de plus de 290 cm représentent des indices de condition corporelle alternatifs intéressants. / Evaluation of the body condition of beluga carcasses from the Estuary of the St. Lawrence contributes to the diagnosis of the cause of death by the pathologist. The current method relies on a subjective visual evaluation. Our project aimed at developing an objective tool for the evaluation of body condition. The Scaled Mass Index (M̂ i) is an objective figure since it is obtained from individual masses and lengths. M̂ i has to be calculated with different constants for belugas under and above a length of 290 cm. M̂ i yielded results consistent with visual evaluation. Since weighing belugas can be logistically impossible, we evaluated indices based on several other morphometric measurements. Indices based on girth at the level of the anus and maximal girth for animals under and above 290 cm, respectively, were deemed useful as alternative body condition indices.

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