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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

A Colorful Past: Turquoise and Social Identity in the Late Prehispanic Western Pueblo Region, A.D. 1275–1400

Hedquist, Saul, Hedquist, Saul January 2017 (has links)
Turquoise is synonymous with the U.S. Southwest, occurring naturally in relative abundance and culturally prized for millennia. As color and material, turquoise is fundamental to the worldviews of numerous indigenous groups of the region, with notable links to moisture, sky, and personal and familial vitality. For Pueblo groups in particular, turquoise and other blue-green minerals hold a prominent place in myth, ritual, aesthetics, and cosmology. They continue to be used as important offerings, deposited in shrines and decorating objects like prayer-sticks and adornments. Archaeological occurrences of turquoise in contexts such as caches, structural foundations, and burials demonstrate its important, perhaps ritually oriented role in prehispanic Pueblo practices. This research examines the myriad uses of turquoise and other blue-green minerals in the late prehispanic Western Pueblo region of the U.S. Southwest (northeastern Arizona and western New Mexico, A.D. 1275–1400). I assess the distribution and depositional patterning of turquoise to explore the role of social valuables in expressing similarities or differences among groups at various social scales. In recent decades, studies of material culture from late prehispanic contexts (most commonly ceramics) have broadened understandings of settlement-specific demographics, the direction and approximate size of distinct population movements, and the structure and transformation of social networks. Such studies have revealed complex and variable relationships between settlements, even those located within distinct settlement clusters. While building upon these insights, this study provides a different, yet comparable outlook by focusing on turquoise, its various uses in social or ritual settings, and its involvement in expressing social or ideological connections that may have differed from other material forms. The project employs a multidisciplinary approach, incorporating archaeology, geochemistry, and ethnography in an effort to address a central research question: How did the circulation and consumption of turquoise vary throughout the late prehispanic Western Pueblo region, and what are the implications for understanding interactions and identity expressions within and among aggregating settlements and settlement clusters? The ancient role of turquoise and other blue-green materials in social identification was explored through several angles, including: 1) spatiotemporal patterns in the stylistic characteristics of ornaments and painted media (e.g., shape and size of beads and pendants or designs on blue-green painted objects); 2) the context and content of archaeological deposits with turquoise (i.e., uses beyond personal and ceremonial adornment, such as ritual offerings); and 3) regional patterns of mineral acquisition and exchange using measurements of heavy stable isotopes. Interviews with Hopi and Zuni consultants—jewelers, artists, and cultural experts—augmented the study by incorporating the participation and perspectives of descendent communities. Taken together, patterns of use and acquisition provide novel means of assessing social or ideological connections between late prehispanic Pueblo communities, and help to clarify the complex and multifaceted ways past Pueblo groups materially expressed their social identities. Woven with contemporary Pueblo sentiments, these data provide indisputable evidence of a colorful and spiritual past.
2

Stress Response and Acclimation in the Adult Turquoise Killifish Nothobranchius furzeri

Henderson, Dallas Wade 01 August 2016 (has links)
The turquoise killifish Nothobranchius furzeri is an increasingly popular model species for comparative vertebrate research. As such, the basic physiology, including responses to one or multiple stress events are of primary interest to the present study. After successful rearing, adult male and female killifish were exposed to one or more acute confinement events. Whole-blood was taken from adult males, in addition to male and female whole-body samples for cortisol analysis. Separate adults were also sampled for tissue specific expression of corticotropin releasing hormone (CRH), mineralocorticoid receptor (MR), and glucocorticoid receptor (GR) mRNA within the cranium, gills, and liver. Following a 30 minute confinement stress, male plasma cortisol significantly differed from baseline at 30 minutes (P=0.04). Similarly, both male and female whole-body cortisol were significantly increased (P=0.004 and P=0.04, respectively) at 15 and 30 minutes post-stress. Whole-body cortisol did not differ between the sexes at any sampling point, however; expression of gill MR at 15 minutes was significantly higher in males (P=0.05). Exposure to daily repeated confinement affected the cortisol response in both males and females, resulting in lower baseline and 60 minutes post-stress values in repeatedly-stressed males (P=0.04 and P=0.006, respectively) and lower cortisol at 30 and 120 minutes post-stress in repeatedly-stressed females (P=0.04 and P=0.04). Repeated exposure also resulted in increased cranial CRH and MR at 15 minutes post-stress (P=0.02 and P=0.05, respectively) compared to singly-stressed males. In females, repeated exposure increased gill MR at 120 minutes (P=0.05), but a single stressor resulted in relatively greater expression of cranial CRH at 120 minutes (P=0.02) and MR at 15 minutes (P=0.05). Collectively, the reduced cortisol production observed in repeatedly-stressed adults coupled with only transient changes in receptor expression suggest acclimation to daily stressors can be detected in as little as one week in adult turquoise killifish. This is also the first description of the stress response on this important model species.
3

Analyse des processus d’engagement dans un projet de territoire : exemple de l’ « économie turquoise » dans les Côtes-d’Armor / An analysis of the process of stakeholder engagement in a regional development project : Example of the "turquoise economy" in the French Department of Côtes-d'Armor

Bourhis, Marion Christina 12 July 2016 (has links)
Le projet de territoire est devenu l’un des outils privilégiés pour une action publique territoriale concertée, sur une scène publique territoriale beaucoup moins hiérarchique et plus fragmentée que par le passé. Mais bien que présenté comme un outil permettant la coordination, sinon la coopération, le projet de territoire ne s’affranchit pas des hiérarchies entre les acteurs et des relations de pouvoir. Comprendre l’engagement ou non des acteurs dans ces projets nécessite alors d’identifier et d’analyser les déterminants de l’action et le contexte dans lequel elle se déroule. Partant d’une étude de cas, l’ « économie turquoise » (projet porté par le Conseil départemental des Côtes-d’Armor), ce travail de thèse s’intéresse ainsi aux processus d’engagement et de désengagement des acteurs dans l’élaboration et la mise en œuvre de ces projets. Afin de tenter de saisir ces processus dans leur globalité (et non dans leur exhaustivité), sont mobilisées des approches issues de cadres théoriques différents permettant d’articuler l’analyse des trajectoires individuelles à celles des collectifs dans lesquels elles s’exercent. Grâce au bénéfice d’une convention CIFRE, le choix d’une approche ethnographique du terrain a été adopté. Elle s’appuie sur une triangulation basée sur la réalisation d'entretiens semi-directifs, d’une analyse documentaire et d’une observation (parfois participante) de la démarche en construction. Ce travail démontre, tout d’abord, que le projet est loin de former un tout isolé, clairement identifiable, s’inscrivant dans une temporalité bien délimitée. De plus, grâce à la mobilisation privilégiée de la théorie de l’acteur-réseau, de la théorie des liens faibles et des économies de la grandeur, cette recherche analyse minutieusement le processus d’élaboration et de mise en œuvre de l’« économie turquoise », tout en révélant les modalités d’interactions entre les acteurs concernés et la construction des compromis. Les résultats exposent également comment le projet se trouve pris en tension entre une visée instrumentale et une volonté de co-construction. L’analyse montre ainsi que de l’enrôlement ne découle pas de facto une forme d’implication dans l’action. Elle explique, de plus, comment le territoire se constitue en tant qu’actant non-humain des projets de territoire influençant ainsi l’engagement des acteurs dans ces projets. Enfin, à partir des relations entre les différentes entités du réseau, ce travail identifie comment les acteurs, par leurs appartenances multiples, peuvent se constituer en tant que vecteurs de liens privilégiés pour élargir le réseau ou, au contraire, en tant qu’écrans. Enfin, une analyse réflexive et épistémologique, restituant le contexte d’implication et de collecte des données, apporte des éléments de réflexion sur la construction d’un parcours de jeune chercheur. / Regional development projects are frequently supported through collaborative action, and take place in an environment that is less hierarchical and more fragmented than the past. Although presented as a focus for coordination, and/or cooperation, the regional development project does not eliminate hierarchies between stakeholders and the associated power relationships. Understanding the engagement, or not, of the stakeholders in these projects makes it necessary to identify and to analyze the determining factors for the action and the context in which it takes place. Starting out from a case study, the “turquoise economy” (a project supported by the French department of Côtes-d’Armor), the work within this thesis focuses on the process of engagement and/or disengagement of the stakeholders in the development and the implementation of regional projects. In order to explore this process holistically, approaches emerging from different theoretical frameworks have been utilised to analyse the contrasting ways in which stakeholders engage or not in collective action. Thanks to a “CIFRE agreement”, the choice of an ethnographical research was able to be followed. A triangulation method was adopted; semi-structured interviews, analyzing documentation, observing the development of the project and at times taking part in it. First of all, this work demonstrates that the case study project is far from forming an isolated whole, clearly identifiable, set in a well bounded temporality. Furthermore, thanks to the chosen use of the actor-network theory, the Strength of weak ties theory and the economies of worth theory, this research analyzes thoroughly the process of developing and implementing the case study project, whilst also revealing the modalities of interactions between the stakeholders and the compromises they make. The results also set out the reasons why there is tension in the case study project because it is caught between a desire to achieve a pre-defined objective and a wish to demonstrate co-construction. The analysis shows that the enrolment of stakeholders does not infer de facto their involvement in the action. Furthermore, the analysis demonstrates that stakeholders have different perceptions of the project, not necessarily coterminous, that influenced their engagement in the project. Finally, by analyzing the relationships that exist between the various stakeholders on the project and their relationships beyond the project, this work identifies how the stakeholders, with their different affiliations can become influential in the widening of the network or, on the contrary, act as opaque screens. The work concludes with a reflexive and epistemological analysis based on the researcher’s experiences of being involved in the project and the process of data collection. Recommendations are provided on how a young researcher might overcome some of the challenges faced in undertaking a project of this nature.
4

Hydrothermal alteration and mineralization in the East Camp of the Turquoise district, San Bernardino County, California

Hall, Denis Kane, 1940- January 1972 (has links)
No description available.
5

Turquoise: its history and significance in the Southwest

Muir, Gertrude Hill January 1938 (has links)
No description available.
6

Turquoise exchange and procurement in the Chacoan World

Hull, Sharon Kaye 18 September 2012 (has links)
The large amount of turquoise artifacts recovered from archaeological sites in the American Southwest and Mesoamerica suggests that turquoise was an important commodity in pre-Columbian trade networks. However, the spatial and temporal patterns of turquoise exchange networks and the provenance regions of the turquoise in the southwestern United States and Mesoamerica are poorly understood. Turquoise (CuAl6(PO4)4(OH)8•4(H2O)) is a supergene mineral that forms from meteoric water along fractures that are often associated with copper porphyry deposits. This copper-rich mineral can range in color and chemistry within a single sample or deposit. The ability to identify the turquoise resource areas of turquoise artifacts using the stable isotopes of hydrogen (2H/1H) and copper (65Cu/63Cu) has overcome many of the limitations of trace element analyses of complex minerals such as turquoise. The geography and geology of turquoise deposits dictate the isotopic composition of turquoise. Employing the Secondary Ion Mass Spectrometry (SIMS) technique to measure the hydrogen and copper stable isotope ratios in turquoise samples, a comparative reference database consisting of 876 analyses from 21 turquoise resource areas in the western United States was established. Sixty-two turquoise artifacts recovered from Aztec Ruin, Salmon Ruin, and nine sites in Chaco Canyon were analyzed and their isotopic signatures were compared to the reference database identifying the turquoise resource areas of 35 artifacts. These results were compared to pre-existing models of trade and exchange in the American Southwest and models that explain the complex culture history of the inhabitants of these sites. The results showed that turquoise was obtained from several different turquoise provenance regions across the western United States and there are notable differences in the turquoise procurement patterns between the three major great houses and between Pueblo Bonito and the small sites within Chaco Canyon. The results from this study improved the understanding of turquoise trade and relationships among the occupants of important Ancestral Puebloan sites in northwestern New Mexico. The development of the turquoise comparative reference database established the foundation of future research for reconstruction of ancient turquoise trade networks and investigation of turquoise procurement strategies in the American Southwest and Mesoamerica.
7

Turquoise exchange and procurement in the Chacoan World

Hull, Sharon Kaye 18 September 2012 (has links)
The large amount of turquoise artifacts recovered from archaeological sites in the American Southwest and Mesoamerica suggests that turquoise was an important commodity in pre-Columbian trade networks. However, the spatial and temporal patterns of turquoise exchange networks and the provenance regions of the turquoise in the southwestern United States and Mesoamerica are poorly understood. Turquoise (CuAl6(PO4)4(OH)8•4(H2O)) is a supergene mineral that forms from meteoric water along fractures that are often associated with copper porphyry deposits. This copper-rich mineral can range in color and chemistry within a single sample or deposit. The ability to identify the turquoise resource areas of turquoise artifacts using the stable isotopes of hydrogen (2H/1H) and copper (65Cu/63Cu) has overcome many of the limitations of trace element analyses of complex minerals such as turquoise. The geography and geology of turquoise deposits dictate the isotopic composition of turquoise. Employing the Secondary Ion Mass Spectrometry (SIMS) technique to measure the hydrogen and copper stable isotope ratios in turquoise samples, a comparative reference database consisting of 876 analyses from 21 turquoise resource areas in the western United States was established. Sixty-two turquoise artifacts recovered from Aztec Ruin, Salmon Ruin, and nine sites in Chaco Canyon were analyzed and their isotopic signatures were compared to the reference database identifying the turquoise resource areas of 35 artifacts. These results were compared to pre-existing models of trade and exchange in the American Southwest and models that explain the complex culture history of the inhabitants of these sites. The results showed that turquoise was obtained from several different turquoise provenance regions across the western United States and there are notable differences in the turquoise procurement patterns between the three major great houses and between Pueblo Bonito and the small sites within Chaco Canyon. The results from this study improved the understanding of turquoise trade and relationships among the occupants of important Ancestral Puebloan sites in northwestern New Mexico. The development of the turquoise comparative reference database established the foundation of future research for reconstruction of ancient turquoise trade networks and investigation of turquoise procurement strategies in the American Southwest and Mesoamerica.
8

Kinetics of the Catalytic Decomposition of Methane into Pure Hydrogen and Carbon on a Silica-Supported Nickel Catalyst

Babkoor, Mohammed 12 1900 (has links)
The catalytic decomposition of methane offers an interesting route to obtain a stream of pure COx-free hydrogen and carbon materials in the solid phase with potential applications to improve the viability of the process. In this work, we have studied the kinetics of this process using a silica-supported nickel catalyst in a packed bed reactor. In order to ensure the intrinsic kinetic regime, the effects of external and mass transfer on the overall kinetics were examined at relevant reaction conditions. The external mass transfer was found to affect the kinetics at 500 ⁰C and a space velocity of 80 h–1. The internal mass transfer was found to not limit the kinetics when a catalyst particle size in the range of 1000-2000 µm was used. Within the intrinsic kinetic regime, we found that the reaction order with respect to methane is in the range of 0.77-0.94, the activation energy is 110 kJ mol–1 and the rate determining step is the dissociation of the first C-H bond. In addition, the kinetics of the catalyst deactivation follows a first-order behavior with respect to the activity of the catalyst, with an activation energy of 125 kJ mol–1. At the end of the study, a mathematical model for the best-fit model was found using MATLAB. With the whole set of data, the best fit is obtained with a Langmuir-Hinshelwood type rate law.
9

Isotopic Evidence for the Provenance of Turquoise, Mineral Paints, and Metals in the Southwestern United States

Thibodeau, Alyson Marie January 2012 (has links)
Lead and strontium isotopes are two powerful tracers that can be used to identify or constrain the provenance of a wide range of archaeological materials, but these two isotopic tracers have been rarely employed to infer the sources of artifacts in the southwestern USA. This dissertation contains four studies that demonstrate how these isotopic systems can address questions about the sources of three types of archaeological materials found in this region: turquoise, lead-based glaze-paints, and metals. The analysis of 116 samples of turquoise from 17 deposits in the southwestern USA reveals that lead and strontium isotopes are robust and sensitive tracers of turquoise at multiple scales. Isotopic variation among turquoise deposits correlates with broad regional differences in the geologic and tectonic setting of the rocks and mineral deposits which host turquoise mineralization. Many turquoise deposits also have unique isotopic signatures that will enable insights into ancient patterns of turquoise acquisition at regional and local levels. To show the utility of these tracers when applied to archaeological turquoise, I use lead and strontium isotopic measurements to establish that the Silver Bell Mountains are the likely source turquoise found at the Redtail site in the Tucson Basin, Arizona, USA. This dissertation also contains new, high-precision isotopic ratios of lead ores (galena and cerrusite) from four mining districts in New Mexico, including the Cerrillos Hills. All districts studied are possible sources of lead used by Pueblo IV communities to produce glaze paints. These new measurements, made by multiple-collector ICP-MS, define the isotopic composition of the ore deposits with greater precision and accuracy than achieved in previous studies, indicating an opportunity to improve interpretations about the provenance of lead in glaze paints. Lead isotopes are also found to be useful tools for identifying lead and copper metal associated with the 1540-1542 Vázquez de Coronado expedition. Lead shot and copper crossbow boltheads from two sites with archaeological evidence for the expedition's presence were determined to share similar or identical lead isotopic ratios. I propose this specific isotopic "fingerprint" can be used to identify other artifacts belonging to the expedition in the Southwest.
10

Fremont Finery: Exchange and Distribution of Turquoise and Olivella Ornaments in the Parowan Valley and Beyond

Jardine, Cady Brooke 20 July 2007 (has links) (PDF)
The Fremont tradition developed on the northern Colorado Plateau and eastern Great Basin between A.D. 1 and A.D. 1350 (Talbot 2000a). Research on exotics in the Fremont area, specifically turquoise and Olivella shell, has been sporadic until recently (Hughes and Bennyhoff 1986; McDonald 1994; Janetski 2002). In this thesis, I present new data on Olivella and turquoise artifacts found throughout the Fremont region, including the Parowan Valley sites, Nephi Mounds, and Kay's Cabin, as well as a spatial distribution of Olivella and turquoise in the Fremont area. I performed microprobe analysis on blue-green artifacts from Kay's Cabin and found most are turquoise, although other minerals including variscite, azurite, malachite, and possibly chrysocolla are also present. Also, various experimental methods were used to chemically characterize a turquoise artifact from Parowan Valley (see Appendix A). I analyzed over 350 Olivella artifacts (see Appendix B) and examined modern Olivella shells; therefore, I provide a discussion of the details and differences between the O. biplicata and O. dama species. Through testing Janetski's (2002) trade fair model, I readdress the question of whether or not Olivella and turquoise were distributed across the Fremont region via directional or down-the-line exchange. My research supports Janetski's model and shows that Fremont exotic exchange moved directionally, with Olivella and turquoise artifacts concentrated at central sites on the Fremont landscape. I also explore the possibility that the exchange of Olivella and turquoise to the Fremont area was conducted through different networks. It appears, based on high numbers of turquoise at certain sites and high frequencies of Olivella artifacts at other sites, that these ornaments were not traded together. I examine whether exotic artifacts were differentially distributed among sites in Parowan Valley and within the specific sites and I observed that Olivella and turquoise are most often associated with living areas.

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