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xviii, 326 p. : ill. (some col.), maps. A print copy of this title is available through the UO Libraries under the call number: KNIGHT GN799 .F6 H46 2002 / Archaeological evidence indicates that cold storage of bison meat was consistently practiced on the eastern Snake River Plain over the last 8000 years. Recent excavations in three cold lava tube caves have revealed a distinctive artifact assemblage of elk antler tines, broken handstones, and bison bone in association with frozen sagebrush features. Similar evidence has also been discovered in four other caves within the region. A patch choice model was utilized in this study to address how the long-term practice of caching bison meat in cold caves may have functioned in prehistoric subsistence patterns. Because the net return rate for bison was critical to the model, the hunting success of fur trappers occupying the eastern Snake River Plain during the early 1800s, as recorded in their daily journals, was examined and quantified. According to the model, the productivity of cold storage caves must be evaluated against the productivity of other patches on the eastern Snake River Plain, such as ephemeral ponds and linear river corridors from season to season and year to year. The model suggests that residential bases occurred only within river resource patches while ephemeral ponds and ice caves would contain sites indicative of seasonal base camps. The predictions of the model were tested against documented archaeological data from the Snake River Plain through the examination of Geographic Information Systems data provided by the Idaho Bureau of Land Management. The results of this analysis indicate that seasonal base camps are directly associated with both ephemeral and perennial water sources, providing strong support for the model's predictions. Likewise, the temporal distribution of sites within the study area indicates that climate change over the last 8000 years was not dramatic enough to alter long-term subsistence practices in the region. The long-term use of multiple resource patches across the region also confirms that, although the high return rates for bison made them very desirable prey, the over-all diet breadth for the eastern Snake River Plain was broad and included a variety of large and small game and plant foods. Bison and cold storage caves were a single component in a highly mobile seasonal round that persisted for some 8000 years, down to the time of written history in the 19th Century. / Committee in charge: Dr. C. Melvin Aikens, Chair; Dr. Lawrence Sugiyama ; Dr. Jon Erlandson ; Dr. Dennis Jenkins ; Dr. Cathy Whitlock ;

Resource availability follows seasonal cycles in environmental conditions. To align physiology and behavior with prevailing environmental conditions, seasonal animals integrate cues from the environment with their internal state. One of the systems animals use to integrate those cues is the hypothalamus-pituitary-adrenal (HPA) axis and its primary effector, glucocorticoid hormones. The HPA axis has wide-ranging effects on physiology and behavior and, in the context of a glucocorticoid stress response, is known to mediate tradeoffs between immediate survival and future fitness. The HPA axis also plays an important role in facilitating predictable life-history events. Variation in HPA axis activity has been reported in all vertebrates, often coordinating seasonal reproduction and possibly also transitions between life-history stages. My dissertation research used red-sided garter snakes (Thamnophis sirtalis parietalis) to examine the role of the HPA axis in regulating seasonal life-history transitions, especially in females. In Chapter 2, I hypothesized that seasonal plasticity in stress responses is regulated, in part, by changes in the responsiveness of the adrenal glands to adrenocorticotropic hormone (ACTH). I found that glucocorticoid responses to ACTH challenge were smaller in males than in females during the spring, suggesting that reports of reduced stress responsiveness in males may reflect lower adrenal responsiveness to ACTH. The sex difference in mating season duration and consequently also in the timing of migration led me to hypothesize that sex differences in HPA axis activity could explain sex differences in the timing of migration. Furthermore, adrenal responsiveness to ACTH also varied seasonally in males, but not females, suggesting that female stress responses, which have not been studied, may not vary seasonally. In Chapter 3, I investigated potential seasonal variation in female stress responses, which have not previously been examined. In males, baseline glucocorticoids decrease over the course of the mating season resulting in significantly lower baseline levels in males that have begun to migrate. I hypothesized that a change in HPA axis activity occurs during spring and fall migration. Peak stress-induced glucocorticoid concentration occurred at an earlier sampling time in females during the spring compared to the fall. Peak stress-induced glucocorticoid concentrations also occurred at a later sampling time in migrating females than in pre-migratory females during the spring, suggesting that negative feedback regulation of the HPA axis changes as soon as females begin to migrate during the spring. Female red-sided garter snakes are biennial breeders that give birth approximately every other year implying that a female's recent reproductive history can influence whether or not she will reproduce in a given year. Body condition can be used as a proxy for recent reproductive history and can be related to baseline and stress-induced glucocorticoid concentrations. In Chapter 4, I hypothesized that hormonal and behavioral stress responses vary with body condition. Baseline glucocorticoids did not vary with body condition, but females in low body condition showed a significantly larger increase in plasma glucocorticoids in response to capture stress. Body condition, but not capture stress, influenced latency to copulate, suggesting that females are resistant to the behavioral effects of capture stress during the spring mating season. Only females in low body condition increased latency to copulate in response to injection of a physiological (15 µg) dose of exogenous CORT, while all females responded to a pharmacological (60 µg) dose, indicating that behavioral responses to exogenous glucocorticoids vary with female body condition. These data suggest that variation in body condition may be associated with differences in HPA axis sensitivity and/or glucocorticoid receptor (GR) density in the brain. I directly tested if there is a relationship among body condition, reproductive history and HPA axis activity in Chapter 5. I found that glucocorticoid stress responses and mating behavior did not vary with body condition, nor was body condition related to brain GR or reproductive condition (parturient vs post-parturient females). Only unreceptive females showed a significant stress-induced increase in glucocorticoids, suggesting that reduced stress responsiveness is associated with receptivity. Parturient females mated faster (were more proceptive) than post-parturient females. These data suggest that HPA axis activity influences reproductive "decisions" by modulating receptivity, while proceptivity is related primarily to recent reproductive history. Together, these chapters help characterize how HPA axis activity varies with season, sex, reproductive history and migration status. By systematically probing the HPA axis in a single, tractable system, I have gained insight into how changes in the HPA axis support and modulate transitions between life-history stages. These results highlight the HPA axis' important function in mediating the critical trade-offs all animals must navigate to be successful in a changing world.

The venom of the Eastern coral snake Micrurus fulvius can cause respiratory paralysis in the bitten patient, which is attributable to -neurotoxins (-NTx). The aim of this work was to study the biodistribution and lymphatic tracking by molecular imaging of the main -NTx of M. fulvius venom. -NTx was bioconjugated with the chelator diethylenetriaminepenta-acetic acid (DTPA) and radiolabeled with the radionuclide Gallium-67. Radiolabeling efficiency was 60%-78%; radiochemical purity 92%; and stability at 48 h 85%. The median lethal dose (LD50) and PLA(2) activity of bioconjugated -NTx decreased 3 and 2.5 times, respectively, in comparison with native -NTx. The immune recognition by polyclonal antibodies decreased 10 times. Biodistribution of -NTx-DTPA-Ga-67 in rats showed increased uptake in popliteal, lumbar nodes and kidneys that was not observed with Ga-67-free. Accumulation in organs at 24 h was less than 1%, except for kidneys, where the average was 3.7%. The inoculation site works as a depot, since 10% of the initial dose of -NTx-DTPA-Ga-67 remains there for up to 48 h. This work clearly demonstrates the lymphatic system participation in the biodistribution of -NTx-DTPA-Ga-67. Our approach could be applied to analyze the role of the lymphatic system in snakebite for a better understanding of envenoming.

The topic of this thesis is about experimental study of phenomena which are associated with light propagation in nonlinear dielectric media. In the first part of this work, we study experimentally the snake instability of the bright soliton stripe of the (2+1)-dimensional hyperbolic nonlinear Schrödinger equation. The instability is observed, through spectral measurements, on spatially extended femtosecond pulses propagating in a normally dispersive self-defocusing semiconductor planar waveguide. The second part of this thesis is about light propagation in nonlinear periodic media. We experimentally observe a stationary spatial gap (or Bragg) soliton in a periodic semiconductor planar waveguide. Based on the interference pattern of the soliton beam, we measure the power parameter of the soliton which is related to the position of the spatial spectrum in the linear band gap. Cette thèse de doctorat a pour sujet l’étude expérimentale de phénomènes associés à la propagation de la lumière dans les milieux diélectriques non linéaires. La première partie porte sur la démonstration expérimentale de l’instabilité serpentine d’une bande solitonique dans un système décrit par une équation de Schrödinger non linéaire à (2+1)-dimensions. L’instabilité est observée sur base de mesures du spectre spatial ainsi que du profil spatio-fréquentiel d’une impulsion femtoseconde après propagation dans un guide plan semi-conducteur qui présente une dispersion normale et une non-linéarité défocalisante. Le second thème abordé concerne la propagation de la lumière dans les milieux non linéaires périodiques. Les expériences réalisées ont montré l’existence du soliton de Bragg spatial stationnaire sous forme de faisceaux se propageant dans des guides plans semi-conducteurs périodiquement gravés. Sur base du profil de la distribution modale en intensité du faisceau soliton, il a été possible de mesurer le paramètre de puissance du soliton de Bragg qui détermine la position du spectre spatial dans la bande interdite linéaire.

Rhyolites of the Picabo volcanic field (10.4-6.6 Ma) of the Yellowstone hotspot in eastern Idaho are preserved as thick ignimbrites and lavas along the margins of the Snake River Plain. This study presents new O and Hf isotope data and U-Pb geochronology from individual zircons, O isotope data from major phenocrysts, whole rock Sr and Nd isotope data, whole rock geochemistry, and trace element and volatile analyses of quartz-hosted melt inclusions, which were used to characterize the evolution of rhyolite generation through the eruptive sequence. The chemical composition of the first eruption of the caldera complex, the Tuff of Arbon Valley, suggests magma generation through repeated magma injection into the crust, remelting, crystallization, mixing, and crustal assimilation. Subsequent eruptions have diverse and low δ18O signatures indicating rhyolite generation through the remelting of variably hydrothermally altered volcanics, followed by rapid batch assembly. This thesis includes co-authored material previously published.

Os venenos de serpentes são complexas misturas de proteínas e peptídeos que apresentam uma variedade de atividades biológicas. Estudos apontam para uma rica diversidade de moléculas bioativas de baixa massa molecular nos venenos, como a crotamina, miotoxina A, peptídeos potenciadores de bradicinina (BPPs) inibidores do tipo Kunitz de serinopeptidases e tripeptídeos inibidores de metalopeptidases. O interesse nestas moléculas está relacionado ao potencial uso como agentes terapêuticos contra diversas patologias, como distúrbios da coagulação e modulação da atividade de metalopeptidases, moléculas estas envolvidas com tumorigenêse e outros processos patológicos como inflamação crônica e distúrbios neurológicos. O veneno da serpente Bitis gabonica rhinoceros provoca alterações fisiopatológicas como severa desordem na coagulação sanguínea e danos teciduais seguidos de necrose. No presente estudo foram isoladas e caracterizadas metalopeptidases e serinopeptidases, além de componentes de baixa massa molecular como inibidor do tipo Kunitz e BPPs. Estes peptídeos foram testados quanto a sua capacidade inibitória frente as peptidases endógenas e sequenciados por espectrometria de massa. Os nossos dados mostram que as peptidases isoladas degradam caseína e não tem atividade sobre colágeno. A serinopeptidase tem atividade β-fibrinogenolítica e o inibidor tipo Kunitz isolado apresenta maior capacidade de inibir a quimotripsina, com valor de Ki= 0,07 μM, mostrando-se um promissor substituto ao fármaco aprotinina. Este peptídeo apresentou também atividade citotóxica em células B16F10 e tênue atividade antimicrobiana. Dentre os BPPs identificados, o peptídeo que possui sequência não canônica apresentou a capacidade de potencializar a ação da bradicinina tanto em ensaio edematogênico quanto de inibição da atividade enzimática da enzima conversora de angiotensina. Esses resultados indicam o potencial de peptídeos de venenos animais para o desenvolvimento de novos agentes terapêuticos para o tratamento de enfermidades como hipertensão e distúrbios de coagulação. / Snake venoms are complex mixtures of proteins and peptides with a wide array of activities. Some studies point towards a vast diversity of low molecular mass bioactive molecules in venoms such as crotamine, myotoxin A, bradykinin potentiating peptides (BPPs), Kunitz type serine peptidase inhibitors and tripeptides inhibiting metallopeptidases. The interest on these molecules is related to their potential use as therapeutic drugs against several pathologies such as coagulation disturbs and modulation of the activity of metallopeptidases, involved in tumorigenesis and other disease like chronical inflammation and neurological disorders. The venom of Bitis gabonica rhinoceros promotes severe blood clotting disorders and tissular damages followed by necrosis. In the present study we isolated and characterized metallo and serine-peptidases, as well as as low molecular mass components such as Kunitz inhibitors and BPPs. Those peptides were assayed for their ability to inhibit the venom ednogenous peptidases and were sequenced by mass spectrometry. Our data indicate that the isolated peptidases hydrolyze casein, but not gelatin, indicating that they have no activity on collagen. The isolated serine protase has β-fibrinogenolytic activity and is not inhibited by the endogenous Kunitz peptide isolated from the venom. The Kunitzlike peptide inhibits preferentially chymotrypsin with a Ki of 0.07 μM and appears as a promising substitute for the commercial drug aprotinin. Among the three bradykinin potentiating peptides, two displayed non-canonical sequences, a fact that might represent an interesting field for new studies for the development of new anti-hypertensives. Although displaying mutations in highly conserved regions, the non-canonical BPP potentialized bradykinin in both edematogenic and angiotensin converting enzyme inhibition assays. These results indicate the potential of animal venom peptides for the development of new drugs against Diseases such as hypertension and coagulopathies.

A análise comparativa da obra de José de Alencar levou-nos a observar a expressiva recorrência de um léxico referente à esfera da serpente. Essa constatação permitiu-nos, através dos estudos das Cartas de Erasmo (1865-1868), O Tronco do Ipê (1871) e Til (1872), aventar a tese de uma forma serpentinal nos escritos do autor cearense. A escolha de tais romances fazendeiros e das epístolas não foi aleatória. O Tronco do Ipê apresenta um dos mais belos desdobramentos da estrutura serpentinal que alicerça a obra do autor, a saber, a lenda da Iara. Til, por sua vez, confere um imenso destaque à serpente, tornando-se ela própria um dos personagens da história. Já as Cartas de Erasmo fornece-nos um arcabouço sociopolítico e econômico subjacente à imagem do ofídio. Para sustentar a nossa ideia, recorremos a teóricos como Paul Ricoeur, Philippe Hamon e Peter Brooks, os quais nos ajudaram a formular uma estética serpentinal. Com base em tais perspectivas, examinamos os elementos estruturais presentes na obra alencariana, detendo-nos na dimensão do eixo paradigmático como a metáfora, a descrição e o melodramático e na dimensão do eixo sintagmático, ao considerar, em especial, a sintaxe frasal e melodiosa. / The comparative analysis of the José de Alencars work led us to verify a large frequency of a lexicon concerning the serpents domain. This observation allowed us to formulate the thesis of a serpentine form in the authors writings, through the studies of Cartas de Erasmo (1865-1868), O Tronco do Ipê (1871) and Til (1872). The choice of such books and epistles is not random. On one hand, O Tronco do Ipê presents one of the most beautiful developments of the serpentine structure that supports the work of the author, which is the legend of Iara. On the other hand, Til attributes an immense relevance to the serpent, once it is one of the personages of the story. Finally, the Cartas de Erasmo provides us with a sociopolitical and economic framework that underlies the image of the snake. In order to confirm our idea, we discussed the theory of researchers as Paul Ricoeur, Philippe Hamon and Peter Brooks, who helped us to think about a serpentine aesthetic. We examined the structural elements in the texts of Alencar, looking carefully to the dimension of the paradigmatic axis such as metaphor, the descriptive and the melodramatic and to the dimension of the syntagmatic axis, especially the phrasal and melodious syntax.

A serpente Crotalus durissus , popularmente conhecida como cascavel, pertence à família Viperidae, e como a maioria dos viperídeos, é uma espécie vivípara. Este estudo teve como objetivo descrever a histologia do oviduto de fêmeas adultas e do saco vitelino e cordão umbilical de fetos em estágios gestacionais avançados de Crotalus durissus . A placenta de Crotalus durissus é constituída pela aposição do epitélio de revestimento do oviduto com a membrana corio-alantoidina que recobre o hemisfério embrionário do ovo. Estas se interdigitam sutilmente e separando a membrana corio-alantoidinana e o revestimento do oviduto está um remanescente da casca do ovo, chamada de membrana da casca. Quando avaliada a distribuição das fibras do sistema colágeno na placenta corio-alantoidina observamos que as fibras se distribuem irregularmente formando arcabouços de sustentação para os vasos e conferindo maior resistência nas regiões próximas a superfície logo abaixo do epitélio coriônico. Em estágios avançados de gestação, a parede do oviduto de Crotalus durissus apresenta-se como uma estrutura delgada, composta por um epitélio com células cuboidais, repousando em uma lâmina própria constituída por tecido conjuntivo. A mucosa do oviduto de Crotalus durissus apresenta regiões com projeções semelhantes à vilos, sustentados por eixos de fibras colágenas. Em estágios avançados de gestação, a face voltada para o feto do saco vitelino está revestida por um epitélio de células colunares grandes com núcleo posicionado basalmente, apresentando grânulos eosinófilicos. O conteúdo vitelino é, basicamente, constituído por depósitos celulares ricos em proteína e muito eosinofílicos. A distribuição do vitelo parece apresentar uma organização em forma de cachos de uvas sendo os ramos constituídos por trabéculas de células que trazem consigo vasos sanguíneos. Em Crotalus durissus , o cordão umbilical promove a conexão entre os tecidos maternos e os fetos, sendo uma estrutura ricamente vascularizada, constituído por duas artérias e uma veia e o ducto alantoide, envoltos por um tecido mucoide (mesenquimal) / The snake Crotalus durissus, popularly known as rattlesnake, belongs to the family Viperidae, and like most viperids, is a viviparous species. This study aimed to describe the oviduct histology of adult females and yolk sac and umbilical cord of fetuses in advanced stages of pregnancy in Crotalus durissus. The Crotalus durissus placenta is formed by affixing the oviduct epithelium lining with chorio-alantoidina membrane covering the embryonic hemisphere of the \"egg\". These interdigitate subtly and separating the chorioalantoidinana membrane and the oviduct of the coating is one of the eggshell remnant, called the shell membrane. When evaluated the distribution of collagen fibers in the system chorio-alantoidina placenta observed that the fibers forming irregularly distributed support frameworks for vessels and providing greater resistance in the regions near the surface just below the chorionic epithelium. In advanced stages of pregnancy, the wall of the oviduct in Crotalus durissus appears as a thin structure made up of a cuboidal epithelium with cells, resting on a lamina consists of connective tissue. The mucosa of the oviduct of Crotalus durissus presents regions with projections similar to the villi, supported by shafts of collagen fibers. In advanced stages of pregnancy, the fetus side facing the yolk sac is coated by a large columnar epithelial cells with basally placed core, with eosinophilic granules. The yolk contents basically comprised of cellular rich protein deposits, and eosinophilic. The distribution of the calf seems to present an organization in a \"bunch of grapes\" being the groups consisting of trabecular cells bring with blood vessels. In Crotalus durissus, the umbilical cord promotes the connection between fetal and maternal tissues and is a highly vascularized structure, consisting of two arteries and one vein, and the allantoic duct, surrounded by a mucoid tissue (mesenchymal)

The paleontology of reptiles in the Caribbean is a topic of great interest to understand how the current fauna of the area was constituted from colonization and extinction of their groups. The largest number of fossils belongs to Squamata, ranging from the Eocene to our days. The registry covers all the islands of the Greater Antilles, most of the Lesser Antilles, and of the Bahamas. Cuba, the largest island of the Antilles, has a relatively sparse Squamata fossil record, with 11 known species from 10 locations, distributed in the West and Center of the Country. However, there are many other fossils deposited in biological collections without identification that could better clarify the history of their reptile fauna. A total of 328 fossils from three paleontological collections were selected for their analysis, searching osteological characteristics that would serve to diagnose them at the lowest possible taxonomic level, and compare them with other fossils and recent species. In the present work, the Squamata fossil record is increased, both in the number of species and in the number of localities. The registry is extended to practically all of the Cuban territory. Fossil remains belonging to previously reported species are confirmed, such as Leiocephalus cubensis, L. carinatus, Tarentola americana, Chilabothrus angulifer, and Cubophis cantherigerus. Fossils of Amphisbaena, Pholidoscelis auberi, and Leiocephalus macropus are described for the first time. Besides, other fossils belonging to the genera Tarentola, Leiocephalus, and Chilabothrus but different from the species that currently inhabit the archipelago, are described. These results show that the Squamata fossil record in Cuba is broader than what was previously considered, despite being composed of very fragile and small fossils with little potential for fossilization. For the paleontology of Squamata the description of new taxa and record of new localities in Cuba, are the first steps for more integrating studies on biological diversity, evolution, biogeography, paleoenvironment among others that contribute to the understanding of the fauna in the Caribbean region. / A paleontologia de répteis no Caribe é um tema de grande interesse para entender como a fauna atual da área foi constituída a partir da colonização e extinção dos seus grupos. O maior número de fósseis pertence a Squamata, que vai desde o Eoceno até nossos dias. O registro abrange todas as ilhas das Grandes Antilhas, a maioria das Pequenas Antilhas e as Bahamas. Cuba, a maior ilha das Antilhas, tem um registro fóssil de Squamata relativamente escasso, com 11 espécies conhecidas de 10 localidades, distribuídas no oeste e centro do país. No entanto, existem muitos outros fósseis depositados em coleções biológicas sem identificação, que poderiam esclarecer melhor a história de sua fauna de répteis. Um total de 328 fósseis de três coleções paleontológicas foi selecionado para sua análise, buscando características osteológicas diagnosticas do menor nível taxonômico possível, e comparando-os com outros fósseis e espécies recentes. No presente trabalho, o registro fóssil de Squamata foi aumentado, tanto em número de espécies quanto em número de localidades. O registro foi estendido a praticamente todo o território cubano. Restos fósseis pertencentes às espécies relatadas anteriormente são confirmados, como Leiocephalus cubensis, L. carinatus, Tarentola americana, Chilabothrus angulifer e Cubophis cantherigerus. Fósseis de Amphisbaena, Pholidoscelis auberi e Leiocephalus macropus foram descritos pela primeira vez, bem como de outros fósseis pertencentes aos gêneros Tarentola, Leiocephalus e Chilabothrus, mas diferentes das espécies que atualmente habitam o arquipélago. Esses resultados mostram que o registro fóssil de Squamata em Cuba é mais amplo do que era considerado anteriormente, apesar de ser composto de fósseis muito frágeis e pequenos, com pouco potencial para a fossilização. Para a paleontologia de Squamata, a descrição de novos táxons e registro de novas localidades em Cuba são os primeiros passos para estudos mais integradores sobre diversidade biológica, evolução, biogeografia, paleoambiente entre outros que contribuam ao entendimento da fauna na região do Caribe.