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Nilsson, Philip. "Topology optimization of a swing arm for a track driven vechile." Thesis, Umeå universitet, Institutionen för fysik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-149608.
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The development in additive manufacturing methods has cleared the path for topology optimizationby making it possible to produce complex geometries, which would not be possible to produce bytraditional manufacturing methods. Topology optimization uses iterative structural computations tond an optimal material distribution given a maximum optimization domain, load cases and/or otherstructural criteria. The relation between retained mass and structural performance of a swing armfor the vehicle BvS10 was examined for two different materials. The first material was an estimate of an additive manufactured material and the other for a high structural steel. Given the extreme load cases, the geometrical limits of the swing arm and by specifying how much mass was to be retained the stiffness was to be maximized. The optimization was performed using an elastic material model in thecommercial software ANSYS. This elastic material models was based on standard material parameters of steel. Three geometries were generated, namely OG100, OG90 and OG80, which corresponded to 101 %, 87 % and 81 % of the mass of the original swing arm, respectively. The optimization procedurewas combined with geometry modications in SpaceClaim to simplify the obtained geometries. All these geometries consisted of a hollow geometry with a greater width compared to the original geometry. The geometries were then evaluated using multilinear plastic material models based on respective material. Using the additive manufactured material model no generated geometry could perform structurally better than the original swing arm. This indicates that greater material properties must be obtainedin order to be able to reduce the weight of the swing arm. By using the material properties of the highstructural steel, it was found that at least 31.3 kg per vehicle could be reduced by using the optimizedgeometry OG80, and still not perform structurally worse than of the original swing arm.<br>Utvecklingen inom additiv tillverkning har öppnat vägen för topologioptimering genom att kunna producera komplexa geometrier, som inte skulle vara möjliga att tillverka med hjälp av traditionella tillverkningsmetoder. Topologioptimering använder iterativa hållfasthetsberäkningar för att finna den optimala materialfördelning givet en maximal optimeringsdomän, lastfall och/eller andra strukturella kriterier. Relationen mellan bibehållen massa och strukturella prestationer hos en pendelarm till fordonet BvS10 har undersökts för två olika material. Det ena materialet var en uppskattning av ett additivt tillverkat material och det andra materialet var ett höghållfasthetsstål. Givet dem extrema lastfall, geometriska begränsningar hos pendelarmen och genom specficera hur mycket massa som skulle behållas så skulle styvheten maximeras. Optimeringarna utfördes med en elastisk materialmodell i den kommersiellamjukvaran ANSYS. Denna elastiska materialmodell var baserad på klassiska materialparametrarfor stål. Tre geometrier genererades. Optimeringsproceduren användes i kombination med geometriska modikationer i SpaceClaim för att förenkla de optimierade geometrierna. Dessa var OG100, OG90 och OG80, vilka motsvarade 101 %, 87 % och 81 % av pendelarmens originalvikt. Alla geometrier bestod av en ihålig geometri med större bredd än originalarmens. Geometrierna utvärderades sedan med hjälp av multilinjära plastiska materialmodeller baserat på respektive material. Ingen av dessa geometrier kunde prestera bättre än originalarmen när det additivt tillverkade materialet användes. Detta indikerar att bättre materialegenskaper måste uppnås för att kunna reducera vikten hos pendelarmen. Genom attanvända höghållfasthetsstålet upptäcktes att åtminstone 31.3 kg per fordon kunde reduceras genom attanvända OG80, och fortfarande inte prestera sämre än originalarmen.
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Glass, Jeffrey Lewis. "Experimental Evaluation of a Trailing-Arm Suspension for Heavy Trucks." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/32790.
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This study includes an experimental evaluation of a prototype trailing-arm suspension for heavy trucks. The primary goal of this new suspension is to match or improve the kinematics and dynamic performance of an existing â Z-barâ suspension. Significant reductions in cost, weight, and number of parts are the main reasons for this redesign.
A permanent facility is constructed to support the testing of different heavy truck suspensions. For actuation of the vehicle suspension, hydraulic actuators are used in the kinematics tests in a quasi-dynamic manner. For the dynamic tests, the vehicle is excited using two hydrodynamic actuators. A collection of forces, displacements, velocities, and accelerations are measured during the tests using transducers that were installed on the suspension and test vehicle. The test measurements are analyzed in both time and frequency domains and then the results of the two suspensions were compared to establish the dynamic merits of the prototype suspension.
The kinematics tests include vertical stiffness, roll stiffness, and roll steer measurements for each suspension. The results from the kinematics tests show that the trailing-arm suspension exhibits kinematics traits that are quite similar to the â Z-barâ suspension, within the context of the tests conducted in the study.
The dynamic testing consists of three input signals commonly used for such tests, namely: a chirp signal input, a step signal input, and a range of pure tone inputs. The test results show that the resonant frequencies of the two primary suspensions differ by an amount that is most likely too small to affect ride dynamics. The two suspensions, however, exhibit significantly different damping characteristics. The new suspension has much less frictional damping than the existing suspension. This is expected to provide better ride characteristics, assuming that the primary dampers (shock absorbers) are properly tuned for the vehicle that the new suspension was designed for.<br>Master of Science
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Currie, Lisel D. (Lisel Diane) Carleton University Dissertation Earth Sciences. "The geology and mid-Jurassic amalgamation of Tracy Arm terrane and Stikinia of northwestern British Columbia." Ottawa, 1994.
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Saenz, David Pael. "Measuring College Readiness: Developing a System of On-Track and Off-Track Metrics for Texas High School Students." Thesis, University of North Texas, 2020. https://digital.library.unt.edu/ark:/67531/metadc1707239/.
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The purpose of this study was to analyze and determine the predictive power of individual and a combination of different indicators that are used to determine college readiness. For this study a logistic regression analysis was conducted due to the dichotomous nature of the dependent variable. The dependent variable for the study was the earning of a post-secondary credential. The independent variables included high school diploma type, Advanced Placement course taken, Advanced Placement test performance, SAT performance, ACT performance, a multidimensional index made up of all the variables, and high school GPA. The study found that high school GPA had the strongest odds ratio, Exp(B), for the participants earning a post-secondary credential (Exp(B) = 6.597), followed by diploma type (Exp(B) = 6.316), taking an Advanced Placement course (Exp(B) = 4.368), earning at least one qualifying Advanced Placement test score (Exp(B) = 3.846), a multidimensional index (Exp(B) = 2.318), ACT score (Exp(B) = 1.161) and SAT score (Exp(B) = 1.003). Future analysis is needed by using live data of student's college performance, stratifying the data to account for differences in post-secondary performance by different racial and socio-economic groups, and studying the effects of the State of Texas' chosen college readiness variables.
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Hoffmann, Loren C. "Cerebellar theta oscillations are synchronized during hippocampal theta-contingent trace conditioning." Oxford, Ohio : Miami University, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami1251998588.
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Mainka, Alexander, Anton Poznyakovskiy, Ivan Platzek, Mario Fleischer, Johan Sundberg, and Dirk Mürbe. "Lower Vocal Tract Morphologic Adjustments Are Relevant for Voice Timbre in Singing." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-202679.
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The vocal tract shape is crucial to voice production. Its lower part seems particularly relevant for voice timbre. This study analyzes the detailed morphology of parts of the epilaryngeal tube and the hypopharynx for the sustained German vowels /a/, /e/, /i/, /o/, and /u/ by thirteen male singer subjects who were at the beginning of their academic singing studies. Analysis was based on two different phonatory conditions: a natural, speech-like phonation and a singing phonation, like in classical singing. 3D models of the vocal tract were derived from magnetic resonance imaging and compared with long-term average spectrum analysis of audio recordings from the same subjects. Comparison of singing to the speech-like phonation, which served as reference, showed significant adjustments of the lower vocal tract: an average lowering of the larynx by 8 mm and an increase of the hypopharyngeal cross-sectional area (+ 21.9%) and volume (+ 16.8%). Changes in the analyzed epilaryngeal portion of the vocal tract were not significant. Consequently, lower larynx-to-hypopharynx area and volume ratios were found in singing compared to the speech-like phonation. All evaluated measures of the lower vocal tract varied significantly with vowel quality. Acoustically, an increase of high frequency energy in singing correlated with a wider hypopharyngeal area. The findings offer an explanation how classical male singers might succeed in producing a voice timbre with increased high frequency energy, creating a singer‘s formant cluster.
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Mainka, Alexander, Anton Poznyakovskiy, Ivan Platzek, Mario Fleischer, Johan Sundberg, and Dirk Mürbe. "Lower Vocal Tract Morphologic Adjustments Are Relevant for Voice Timbre in Singing." Public Library of Science, 2015. https://tud.qucosa.de/id/qucosa%3A29495.
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The vocal tract shape is crucial to voice production. Its lower part seems particularly relevant for voice timbre. This study analyzes the detailed morphology of parts of the epilaryngeal tube and the hypopharynx for the sustained German vowels /a/, /e/, /i/, /o/, and /u/ by thirteen male singer subjects who were at the beginning of their academic singing studies. Analysis was based on two different phonatory conditions: a natural, speech-like phonation and a singing phonation, like in classical singing. 3D models of the vocal tract were derived from magnetic resonance imaging and compared with long-term average spectrum analysis of audio recordings from the same subjects. Comparison of singing to the speech-like phonation, which served as reference, showed significant adjustments of the lower vocal tract: an average lowering of the larynx by 8 mm and an increase of the hypopharyngeal cross-sectional area (+ 21.9%) and volume (+ 16.8%). Changes in the analyzed epilaryngeal portion of the vocal tract were not significant. Consequently, lower larynx-to-hypopharynx area and volume ratios were found in singing compared to the speech-like phonation. All evaluated measures of the lower vocal tract varied significantly with vowel quality. Acoustically, an increase of high frequency energy in singing correlated with a wider hypopharyngeal area. The findings offer an explanation how classical male singers might succeed in producing a voice timbre with increased high frequency energy, creating a singer‘s formant cluster.
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Francis, Shawn Michael. "Differences in Ground Reaction Forces between Take-Offs that are Out, On, or Under in the Pole Vault." Thesis, North Dakota State University, 2012. https://hdl.handle.net/10365/26658.
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Aim. The take-off is regarded as the most important phase of the pole vault yet there is an insufficient amount of research on the ground reaction forces of the pole vault takeoff. At this time there is not any scientific research comparing force and time between takeoffs that are out, on and under. The purpose of this study is to compare the differences in ground reaction forces between pole vault take-offs that are out, on or under. Methods. Over five days, 15 male and female college pole vaulters completed 226 vaults on a (AMTI Accupower) force plate. The jumps were put into categories of out, on and under and analyzed by Accupower, and Dartfish software. Separate mixed modal ANOVAs (SAS 9.3) were applied (P?.05) for comparison between jump types. Conclusions. There is no significant difference between ground reaction forces of the three jump types.
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Li, Bohao. "3-D dynamic modeling and simulation of a multi-degree of freedom 3-axle rigid truck with trailing arm bogie suspension." Access electronically, 2006. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20060731.135017/index.html.
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Kumar, Sabhya. "Effects of Constant Track Running Exercise on the Expression of the Immediate Early Gene Arc in the Rat Hippocampus." Thesis, The University of Arizona, 2013. http://hdl.handle.net/10150/297635.
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Arc is an IEG expressed in the CA1 sub-field of the hippocampus, following stimulus from an external environment and is expressed in the place cells involved in spatial learning. An initial experiment showed that Arc expression levels decreased with 25 minute rest periods between sessions. The current study aimed to see if similar results are seen with track running, if the rest periods are removed. The rats ran on a small circular track, ensuring that a small ensemble of place cells activate on each lap. Animals were assigned to 4 groups: positive control for Arc induced by MECS; negative control for animals sacrificed from their home cage; a 5 minute group and a 45 minute group. The brain tissue was stained using FISH. The 45 minute group had a 4% lower Arc expression than the 5 minute group. A univariate ANOVA indicated a statistically significant effect in the main factor of Behavioral Group (F= 6.955, p=0.03). Tukey tests showed that the differences between the MECS and the CC groups (p<0.05) and the MECS and the 45 minute groups (p<0.05) were significant. The behavioral groups showed no statistical significance meaning that massed exposure without rest does not attenuate Arc signal.
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Romeur, Monique, and René Maury. "Séries magmatiques arc et arrière-arc de la Sonde : nature des sources impliquées (éléments en trace et isotopes Sr-Nd-Pb)." Brest, 1991. http://www.theses.fr/1991BRES2006.
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Les volcans quaternaires arriere-arc de java presentent une importante variabilite dans la composition petrologique de leurs produits et dans leur distance par rapport a la fosse. Les laves des ces volcans montrent des caracteristiques en elements en trace typiquement orogeniques, compatibles avec une origine liee a la subduction. Elles ont des compositions isotopiques pb et sr un peu plus faibles que celles des magmas d'arc; les compositions isotopiques du nd sont similaires dans les deux types de magma. Deux correlations compositions isotopiques du nd-rapports th/ta sont mises en evidence: l'une comprend les laves arriere-arc; la seconde les magmas d'arc. A l'aide de ces correlations, trois zones geochimiques ont ete reconnues: un domaine arc, un domaine arriere-arc et un domaine intermediaire comprenant les volcans situes geographiquement entre l'axe de l'arc et les volcans arriere-arc. On propose que les magmas d'arc resultent du melange entre une source murb appauvri (comportant les caracteristiques dupal) et les fluides issus de la plaque subductee. Un melange entre un manteau morb enrichi en elements hygromagmaphiles (contamine par la fusion de croute oceanique subductee, sumatra) et les sediments subductes (par l'intermediaire de fluides metasomatiques) (java) genere les magmas arriere-arc. Les magmas intermediaires sont le resultat d'un melange entre les sources des domaines arc et arriere-arc. Un modele de repartition de ces sources est propose: il est compatible avec la remontee d'un manteau enrichi (domaine arriere-arc) dans un manteau appauvri superficiel (domaine arc)
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Bard-Schwarz, Anna Ewa. "A Philosophy and an Approach to Teaching Non-professional-track Violin Students." Thesis, University of North Texas, 2014. https://digital.library.unt.edu/ark:/67531/metadc500007/.
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The aim of this dissertation is to lay the groundwork for an integrated approach to violin instruction for children who are not being groomed explicitly for professional careers as instrumentalists. The study presents a particular focus on the age of middle school children, in order to showcase a more specialized and definitive result of research without, however, distinguishing between advantages and limitations of different age groups of children who study music and learn to play the violin. My first goal is to craft a sample method of teaching with a premise that not all students studying music must or need to become professional musicians in their future. I promote an approach based on the premise that music has universal value available to all and that any kind of music education encourages the growth, personality development, and imagination of children. My second goal is to explore how music education functions in 21st century western culture. Research is based on teachings and methods established by Suzuki, Kodaly, Jaques-Dalcroze, and Orff, among others.
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Philpot, Denise R. "Tenured/tenure-track Faculty Diversity: Does Search Committee Training Make a Difference?" Thesis, University of North Texas, 2014. https://digital.library.unt.edu/ark:/67531/metadc699983/.
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Diversity impacts organizations, both internally and externally. Responses to changes in demographics come from legal and moral imperatives. As a reflection of the changes in the population demographics in the United States, universities have seen and sought increased diversity in their student enrollment. Many institutions have purposeful plans to increase representation of under-represented groups as well as those students from low-income families. Some schools also recognize the importance of having diversity represented within their staff and faculty positions as a way of creating a supportive environment that also promotes diversity of thought. As schools increase the diversity of their student population, at what level are they increasing diversity among their tenured and tenure-track faculty? The purpose of this study is to examine the impact on full-time tenured/tenure-track faculty diversity compared to enrolled student diversity at institutions that promote, require, or provide access to training for faculty search committees, including diversity/cultural awareness, legal compliance, and process training, and those institutions that do not appear to have any training requirement as documented on their websites. Only tenured/tenure-track faculty were considered as they are the permanent teaching/research positions and generally represent the core faculty of every department at a university.
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Kayser, Paulette. "Emmanuel Lévinas : la trace du féminin /." Paris : Presses universitaires de France, 2000. http://catalogue.bnf.fr/ark:/12148/cb376334762.
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Texte remanié de: Th. doct.--Philos.--Paris 8, 1998. Titre de soutenance : La défaillance du sujet, le féminin différence sexuelle et immémoriale dans les écrits d'Emmanuel Lévinas.<br>Bibliogr. p. 241-251. Index.
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Michel, Jonathan. "Caractérisation par UHV AFM/STM des nanostructures de déformation de l'intermétallique Ni3Al." Thesis, Poitiers, 2014. http://www.theses.fr/2014POIT2321/document.
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Le composé intermétallique ordonné Ni3Al, de structure L12, présente une augmentation de contrainte d'écoulement avec la température, jusqu'à une température dite de "pic" au-delà de laquelle celle-ci décroit. Ce comportement, usuellement appelé anomalie de contrainte d'écoulement, est mis à profit dans les superalliages base nickel pour les applications hautes températures. Il a été étudiée de façon extensive ces trente dernières années et a donné lieu à de nombreuses modélisations. La plupart des modèles proposés considère qu'un processus thermiquement activé de glissement dévié des dislocations, à partir de leur plan de glissement primaire {111} sur le plan cubique de déviation {010}, joue un rôle clé dans la compréhension de l'anomalie. La distance de glissement dévié peut cependant fortement différer. Les traces de glissement laissées par l'émergence des dislocations mobiles à la surface d'échantillons déformés plastiquement permettent de visualiser les événements de déviations et de caractériser les mécanismes élémentaires de déformation plastique. Nous avons mesuré des paramètres essentiels pour modéliser la plasticité globale de l'intermétallique Ni3Al, comme : le nombre, la hauteur, la longueur des traces de glissement correspondant aux plans {111} et {010}. Ces paramètres qui caractérisent à la fois l'activité des sources et le libre parcours moyen des dislocations, suggèrent que l'anomalie s'accompagne d'un fort taux d'épuisement de la densité de dislocations mobiles. De nombreuses longues déviations dans les plans {010} ainsi que des doubles glissement dévié entre plans {111} adjacents, ont été mis en évidence. Ceci suggère deux processus de glissement dévié<br>Ni3Al intermetallic compounds, that correspond to the strengthening phase of nickel-based superalloys, are well known to exhibit within a given range of temperature, an anomalous behaviour of flow strength. This positive temperature dependence of flow strength, called yield stress anomaly (YSA), has been the subject of extensive experimental studies concerning mechanical properties and dislocation microstructures, which have yielded several plausible models. Most of these models considers that a thermally activated cross-slip process, from the primary {111} onto the cube cross-slip {010} planes, plays a key role in the understanding of the YSA. However, the height of the cross-slipped segment in the {010} plane can be drastically different. The slip traces resulting from the emergence of moving dislocations at the surface in plastically deformed samples, allow us to visualize cross-slip events and to characterize the elementary mechanisms controlling plastic deformation. The number, height and length of slip traces corresponding to {111} and {010} planes, that are key parameters for modelling the plastic behaviour of Ni3Al intermetallic, are examined. These parameters reflect both the source activity and dislocation mean free path of dislocations; their values suggest that the YSA takes place with a strong exhaustion of mobile dislocations. Several larger deviations on the {010} planes, as well as double cross-slip between {111} neighbouring planes, are highlighted. These results suggest two different cross-slip process
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Buzard, James. "The beaten track : European tourism, literature, and the ways to culture, 1800-1918 /." Oxford : Clarendon Press, 1993. http://catalogue.bnf.fr/ark:/12148/cb366692486.
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Rushton, D. H., Gillian E. Westgate, and Neste D. J. Van. "Following historical 'tracks' of hair follicle miniaturisation in patterned hair loss: Are elastin bodies the forgotten aetiology?" Wiley, 2021. http://hdl.handle.net/10454/18515.
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Yes<br>Pattern Hair Loss (PHL) is a chronic regressive condition of the scalp, where follicular miniaturisation and decreased scalp hair coverage occurs in affected areas. In all PHL cases there is a measurable progressive shortening of the terminal hair growth duration, along with reduced linear growth rates. In both genders, PHL initially shows an increase in short telogen hairs ≤30mm in length, reflecting a cycle completion of under six months in affected terminal hair follicles. To understand the miniaturisation process, we re-examine the dynamics of miniaturisation and ask the question, 'why do miniaturised hair follicles resist treatment?' In the light of recent developments in relation to hair regeneration, we looked back in the older literature for helpful clues 'lost to time' and reprise a 1978 Hermann Pinkus observation of an array of elastin deposits beneath the dermal papilla following subsequent anagen/telogen transitions in male balding, originally described by Arao and Perkins who concluded that these changes provide a "morphologic marker of the entire biologic process in the balding scalp". Thus, we have reviewed the role of the elastin-like bodies in hair pathology and we propose that alterations in elastin architecture may contribute to the failure of vellus-like hair reverting back to their terminal status and may indicate a new area for therapeutic intervention.
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Bradstreet, Tyler C. "The Effect of Season Performance on Male and Female Track and Field Athletes’ Self-identity." Thesis, University of North Texas, 2013. https://digital.library.unt.edu/ark:/67531/metadc500120/.
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Although the “self” has generally been conceptualized as relatively stable in sport-specific research, events such as deselection, injury, and career termination have been found to negatively affect athletes’ levels of identification with the athlete role. Additionally, there has been limited research regarding competitive failure and its ability to negatively affect athletes’ levels of identification with the athlete role. The purpose of the present investigation was to provide additional evidence regarding the influence poor competitive seasons have on the malleability of athletes’ self-identity. Athletes were followed throughout the course of their season to determine whether athletes who encountered a poor competitive season reported lowered levels of athletic identity. Specifically, male and female NCAA Division I track and field athletes completed pre-indoor, post-indoor, and post-outdoor assessments of athletic identity. Contrary to previous research, the current study’s results indicated no identifiable relationship between male and female athletes’ season performance satisfaction and their level of post-indoor and post-outdoor athletic identity. Thus, the greatest predictor of athletes’ post-season level of athletic identity was their pre-season level of athletic identity, regardless of season performance. Given these results, future research should assess self-esteem as well as other potential coping strategies athletes might use in order to gain a better understanding of the effect encountering a poor competitive season may have on athletes’ self-identity.
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Noury, Mélanie. "Evolution géologique de l'avant-arc sud péruvien : apports des données géo-thermochronologiques." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENU058/document.
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La marge sud péruvienne est située au niveau d’une zone majeure de subduction océan continent depuis au moins le Paleozoique inférieur. C’est dans ce cadre que s’est formé l’un des plus importants orogènes du monde : les Andes Centrales. En effet, l’épaisseur crustale y est >60 km et ce sur une importante surface. Cependant, on considère actuellement que ce surrépaississement a été acquis incrémentalement seulement depuis ~30 Ma. Dans le but de comprendre comment et quand ce surrépaississement est apparu, la majeure partie des études précédentes s’est focalisée sur l’évolution de l’arc magmatique et sur l’histoire de la déformation, du soulèvement et de l’érosion de la zone d’arrière arc. Cependant, l’évolution tectonique et thermique de l’avant arc reste mal connue bien que cette zone soit susceptible de bien enregistrer les changements liés à la dynamique de subduction.Cette thèse à pour objectif de mieux contraindre l’évolution thermique et les couplages entre les processus magmatiques, tectoniques et sédimentaires depuis 200 Ma dans l’avant-arcactuel du sud du Pérou. De nouvelles données géo-thermochronologiques couplées à une nouvelle carte tecto-stratigraphique éclaircissent l’évolution de la marge péruvienne depuis le Jurassique. Trois périodes clefs sont analysées dans ce mémoire : le début de l’épaississement crustal, les déformations de l’avant-arc associées à la formation de l’Orocline bolivien et l’épaississement crustal de l’orogène des Andes Centrales pendant le Néogène.Nous montrons que l’épaississement crustal a probablement commencé entre 90 et 50Ma après plus de 200 Ma d’amincissement, et ce a la faveur d’une évolution en trois étapes :croissance initiale (90-74 Ma), « flare-up » (74-62 Ma) et effondrement extensionnel (62-50Ma). L’extension a ensuite prédominé dans l’avant-arc tout en diminuant progressivement jusqu’à ~30 Ma. Par ailleurs, nous mettons en évidence d’importantes zones de faillesnormales orientées perpendiculairement à la marge sud-péruvienne et qui délimitent de grands blocs basculés vers le nord-ouest. Ces déformations révèlent une extension parallèle à l’orogène dans l’avant arc pendant le Paléogène, probablement due à la formation de l’Orocline bolivien par rotation antihoraire de blocs rigides. Enfin, les traits géomorphiques visibles dans la zone cotiere du sud du Pérou permettent de définir deux périodes de soulèvement de la surface (entre 23 et 10 Ma et depuis ~4.5 Ma), séparées par une période de subsidence (entre ~10 et ~4.5 Ma). La même chronologie ayant été décrite sur le versant Amazonien de l’orogène, nous proposons que cette évolution soit due à des variations à grande échelle de l’épaisseur crustale ; le soulèvement de la surface étant provoqué par addition à la croûte de magma d’origine mantellique et la subsidence par un flux de matériel crustal ductile depuis les zones précédemment sur-épaissies<br>The southern Peruvian margin has been located above a major ocean-continentsubduction zone since at least the Early Paleozoic, resulting in the formation of one of thelargest orogens in the world: the Central Andes, where crustal thickness is >60 km over a largearea. This overthickening is currently thought to have occurred incrementally only during thelast 30 Ma. To understand how and when crustal overthickening was acquired, most of theprevious studies have focused on the magmatic arc evolution and on deformation, uplift anderosion history of the backarc. The tectono-thermal Cenozoic evolution of the forearc remainspoorly known, whereas it is a zone prone to recording changes in subduction dynamics.The objective of this dissertation is to address the thermal evolution and the couplingbetween magmatic, tectonic and sedimentary processes over the past 200 Ma in the presentdayforearc of southern Peru where the crust thickens from ~30 km along the coastline tomore than 60 km under the present-day volcanic arc. New geo- and thermochronological datacoupled to a novel geological map illuminate the evolution of the south Peruvian margin sincethe Jurassic. Three key periods of the margin evolution are addressed in this dissertation: theonset of crustal thickening, the deformations associated in the forearc with the formation ofthe Bolivian Orocline and the Neogene crustal thickening of the Central Andean orogen.We show that crustal thickening likely began between 90 and ~50 Ma after more than200 My of lithospheric thinning during a three step evolution of the magmatic arc as follows:growth (90-74 Ma), flare-up (74-62 Ma), extensional collapse (62-50 Ma). Extension prevailedin the forearc since then and waned until ~30 Ma. In addition, we evidence important normalfault zones striking perpendicular to the southern Peruvian margin that delineate largenorthwestward tilted blocks. This deformation reveals orogen parallel extension in the forearcduring the Paleogene likely due to the formation of the Bolivian Orocline by counterclockwiserotation of rigid blocks. Finally, geomorphic features in the coastal area of southern Perureveal two periods of surface uplift (~23 to 10 Ma and since ~4.5 Ma), separated by a period ofsurface subsidence (from ~10 to ~4.5 Ma). The same chronology has been described on theAmazonian side of the Central Andean orogen. We thus propose that this evolution is due tolarge-scale crustal thickness variations; surface uplift being triggered by addition of mantlederivedmagmas to the crust and subsidence by ductile flow away from the previouslyoverthickened crust
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Douglas, Matthew Aaron. "Commercial Motor Vehicle Driver Safety: An Application of Ethics Theory." Thesis, University of North Texas, 2009. https://digital.library.unt.edu/ark:/67531/metadc11048/.
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Safety is an important aspect of ethical, socially responsible logistics. Current U.S. motor carrier (MC) safety research topical coverage includes the effects of individual and environmental influences, carrier safety management, and regulatory compliance on carrier safety and driver fatigue/safety performance. Interestingly, little research on the subject of truck drivers' safety attitudes and behaviors exists and the underlying decision-making processes that guide drivers' safety-related behaviors have received little attention. Furthermore, researchers have not provided an integrated framework that explains individual, organizational, and regulatory factors' impact on drivers' safety decision-making and performance. Truck drivers' safety judgments, decisions, and actions must adhere to societal safety norms. To that end, ethical decision-making theory that draws from the deontological and teleological traditions in moral philosophy provides a theoretical foundation and integrated framework necessary to better understand drivers' safety decision-making processes. The current research sought to determine how drivers rely on safety norms and perceived consequences in forming safety judgments and behavioral intentions. Furthermore, the study was designed to explore how various factors (i.e., individual, organizational, and regulatory) influence drivers' safety decision-making processes. Specifically, the study sought to answer the broad question, "How do commercial motor vehicle drivers make safety-related decisions, and how do individual, organizational, and regulatory factors influence drivers' safety decision-making processes?" An experimental two-factor design (2×2) was used to manipulate safety norms (i.e., "deontologically unsafe situation" and "deontologically safe situation") and consequences (i.e., "positive consequences" and "negative consequences"). Multivariate statistical analysis revealed that drivers primarily rely on deontological evaluations in forming safety judgments. Furthermore, drivers primarily relied on safety judgments when forming behavioral intentions. Drivers' attitudes toward unsafe actions and the effectiveness of driver-related safety regulations were also influential to drivers' judgments and intentions, respectively. The empirical findings demonstrate to managers that communication and education of safety norms may be highly effective to improve safety in unique occupational contexts where employees are given high levels of responsibility with little physical supervision, and where judgment errors can have devastating consequences for multiple stakeholders.
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Vigus, Robert T. "Fortification Renaissance: the Roman Origins of the Trace Italienne." Thesis, University of North Texas, 2013. https://digital.library.unt.edu/ark:/67531/metadc271911/.
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The Military Revolution thesis posited by Michael Roberts and expanded upon by Geoffrey Parker places the trace italienne style of fortification of the early modern period as something that is a novel creation, borne out of the minds of Renaissance geniuses. Research shows, however, that the key component of the trace italienne, the angled bastion, has its roots in Greek and Roman writing, and in extant constructions by Roman and Byzantine engineers. The angled bastion of the trace italienne was yet another aspect of the resurgent Greek and Roman culture characteristic of the Renaissance along with the traditions of medicine, mathematics, and science. The writings of the ancients were bolstered by physical examples located in important trading and pilgrimage routes. Furthermore, the geometric layout of the trace italienne stems from Ottoman fortifications that preceded it by at least two hundred years. The Renaissance geniuses combined ancient bastion designs with eastern geometry to match a burgeoning threat in the rising power of the siege cannon.
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Di, Bella Marcella. "Studio archeometrico di macine in pietra lavica provenienti da siti archeologici di Messina e provincia." Doctoral thesis, Università di Catania, 2013. http://hdl.handle.net/10761/1353.
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E stato intrapreso lo studio archeometrico di macine in pietra lavica, provenienti da vari siti archeologici della città di Messina e provincia. L analisi archeometrica ha compreso la caratterizzazione petrochimica delle litologie utilizzate per la loro costruzione e l attribuzione di provenienza degli stessi materiali. I campioni studiati sono stati suddivisi in due gruppi di differente età, un gruppo dell età del Bronzo Antico e l altro di Epoca Romana. La tipologia dei manufatti è varia, e partendo dalle rudimentali mole preistoriche, si giunge alle più avanzate mole asinarie adoperate in Epoca Romana fino al Medioevo. La maggior parte di questi manufatti erano ottenuti da rocce vulcaniche scoriacee, selezionate per le loro caratteristiche tessiturali e fisiche peculiari, quali elevata resistenza, durezza e buona porosità, facilità di lavorazione e trasportabilità rispetto ad un basalto massivo.
I due gruppi di campioni di macina sono stati prima caratterizzati dal punto di vista petrografico, microanalitico e geochimico-geodinamico. Per definire la probabile area di provenienza, sono stati utilizzati diagrammi di variazione degli elementi in tracce, alcuni costruiti opportunamente ed altri gia utilizzati in letteratura per la classificazione di simili manufatti litici. Infine tutti i dati, quelli geochimici in particolare sono stati confrontati con dati di letteratura di rocce provenienti dai siti vulcanici prima identificati, per verificare la effettiva comparabilità.
I risultati del presente lavoro di tesi apportano un contributo importante per la definizione delle rotte commerciali del Mediterraneo, confermando la presenza di scambi commerciali e culturali gia a partire dall Età del Bronzo antico, periodo a cui appartengono i campioni della serie preistorica. La presenza, all interno dello scavo preistorico, di macine ed elementi di macina provenienti da siti così differenti, come Etna, Eolie e Santorini è una testimonianza tangibile dell intraprendenza dell uomo primitivo che per necessità di sussistenza e di miglioramento della propria condizione di vita, si spinse sempre più in là. In particolare il rinvenimento del campione (pestello) che risulta provenire dall area Egea conferma che già in epoca preistorica esistevano scambi tra le popolazioni dell areale Tirrenico e quelle Egee. La caratterizzazione delle macine di Epoca Romana, ha invece permesso di ampliare il quadro delle conoscenze relativamente alla diffusione delle macine nel bacino del Mediterraneo e di confermare l utilizzo di alcuni siti vulcanici quali Etna, Linosa, Pantelleria e Colli Euganei come cave di materiale grezzo per l allestimento di manufatti atti alla macinazione dei cereali.
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Ali, Ased Syed Mohammed. "Are beta defensin 1 and beta defensin 2 key innate immune effector peptides against urinary tract infection in women?" Thesis, University of Newcastle upon Tyne, 2013. http://hdl.handle.net/10443/2311.
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Introduction & Hypothesis Recurrent urinary tract infection (rUTI) is a debilitating problem affecting 5% of women. Current treatment using intermittent or long-term antibiotics gives limited symptomatic benefit and encourages bacterial resistance. The aetiology of rUTI is unclear but may involve altered innate defence mechanisms in susceptible individuals. Colonisation of vaginal mucosa by uropathogenic Escherichia coli (UPEC) is the initiating event for UTI, with subsequent migration up the urethra and attachment to bladder epithelium. Protective innate immunological mechanisms include epithelial synthesis of cationic antimicrobial peptides (AMPs) such as the beta defensins. These may be expressed constitutively or induced via Toll-like-receptor (TLR) activation by pathogen associated molecular patterns (PAMPs). This study investigates the hypothesis that women suffering from rUTI have altered tolerance to infecting bacteria related to differences in expression of endogenous AMPs and that identification of such deficiency gives a potentially useful opportunity for novel preventive therapy. Methods and Patients A synergistic methodological approach of in vitro modelling with validation in clinical samples from the relevant patient group and controls was used. In vitro, cell culture was carried out using RT4 immortalised urothelial-cells, VK2 E6/E7 immortalised vaginal cells and finite primary culture of normal human urothelium. Cells were challenged with E. coli and PAMPs. Assays for Beta defensin AMP gene expression, secretion and antimicrobial activity were carried out. Clinically, 98 women (60 rUTI, 38 controls) were recruited with ethical approval. All subjects provided symptom and health state questionnaires; blood for single nucleotide polymorphism (SNP) analysis; vaginal and bladder biopsies for AMP gene expression analysis; plus vaginal washings and overnight urine samples for AMP peptide secretion assays. Results In vitro, cell culture experiments demonstrated that beta defensin 1 (BD1) was constitutively expressed and secreted in urothelial and vaginal cells. Beta defensin 2 (BD2) expression and secretion was induced by E. coli flagellin and is a potent antimicrobial against UPEC. In vaginal cells, BD2 expression and secretion was enhanced by estrogen. Clinically, women with rUTI were identified as having significantly lower basal levels of vaginal BD2 expression and secretion than controls but no difference in BD1 expression. Postmenopausal women had significantly lower BD2 levels than pre-menopausal women. 392Stop During active UTI, women with history of rUTI and the TLR5 SNP showed significantly lower BD2 expression and secretion in both the bladder and vagina than women with wild type TLR5 gene and rUTI. Discussion This study identifies flagellin induced BD2 expression as a novel and important urogenital innate immune response against invading E. coli, which is reduced in a significant proportion of women with rUTI particularly those with the TLR5 392Stop SNP. Observations in vitro on the BD2 inducing effect of estrogen, and clinically in pre- and post-menopausal women, raise the possibility that BD2 expression can be modulated by exogenous factors.
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Zhang, Lu. "Establishment and Development of Antibiotic Resistant Bacteria in Host Gastrointestinal Tract—Food, Drug, or Are We Born with It?" The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1316186957.
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Cassel, Shirley T. (Shirley Tamsen). "Validation of a Test Battery for the Selection of Driver Managers in a Trucking Organization." Thesis, University of North Texas, 1990. https://digital.library.unt.edu/ark:/67531/metadc500800/.
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This study was a concurrent validation of a paper and pencil test battery used at a national trucking company. Forty-eight driver managers were rated by their immediate supervisors with the performance appraisal covering 12 dimensions of job behavior that was developed by the experimenter. The driver managers were also administered the Wesman Personnel Classification Test, the Watson-Glaser Critical Thinking Appraisal, and the California Psychological Inventory (CPI). A biographical information blank was also developed and validated. Most validity correlations were nonsignificant, with the exception of the Dominance scale r = .25 (p < .05), the Self-control scale r = -.25 (p < .05), the Communanlity scale r = .29 (p < .05), and the Flexibility scale r = -.39 (p < .05), with overall performance.
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Besson, Daniel. "Le corps fragmenté : trace du sujet et empreinte de l'auteur /." Paris : Université de Paris VIII, 1993. http://catalogue.bnf.fr/ark:/12148/cb370670635.
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Goetz, Rose. "Destutt de Tracy philosophie du langage et science de l'homme /." Lille 3 : ANRT, 1989. http://catalogue.bnf.fr/ark:/12148/cb37613977c.
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Escassut, Rémy. "Trace automatique hiérarchisé d'interconnexions de blocs fonctionnels de circuits intégrés V.L.S.I." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376135162.
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Hars, Bernard. "Réactivation de la trace mnésique et sommeil paradoxal étude chez l'animal /." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37614316r.
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Kakizaki, Ichirō. "Laying the tracks : the Thai economy and its railways, 1885-1935 /." Kyoto (Japon) : Melbourne (Australie) : Kyoto University Press ; Trans Pacific Press, 2005. http://catalogue.bnf.fr/ark:/12148/cb401539377.
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Texte fondé sur: Dissertation--Tokyo--University of Foreign Studies, 2000. Titre de soutenance : Thai railways and the formation of Bangkok-centered economic sphere, 1897-1941.<br>Bibliogr. p. 294-313.
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Nygren, Richard Edwin 1964. "Predictive Validity of the Retail Employment Inventory for the Selection of Over-the-Road Truck Drivers." Thesis, North Texas State University, 1988. https://digital.library.unt.edu/ark:/67531/metadc500969/.
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An independent pilot study suggested that the Retail Employment Inventory (REI) might be predictive of subjectively and objectively measured Over the Road (OTR) truck driver performance. The present validation study consisted of three parts. First, an examination of the relationship between REI scores and 11 objective, performance criteria revealed weak and non-significant correlations. Second, a comparison of subjective ratings and REI scores failed to replicate the findings of the pilot study. And third, to confirm that the task components of the OTR job were correctly identified in the pilot study, a second job analysis was performed. Possible reasons for the failure of the REI to predict OTR performance and directions for future research are discussed.
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Ech-Cherif, El Kettani Mustapha. "Caractérisation des fonctions C... dont la trace est C... pour un morphisme fini." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37604797g.
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Engelhart, Monica. "Extending the tracks : A cross-reductionistic approach to Australian Aboriginal male initiation rites." Doctoral thesis, Stockholm : Almqvist & Wiksell international, 1998. http://catalogue.bnf.fr/ark:/12148/cb37702264t.
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Combest, Kyle B. (Kyle Bryan). "Sediment Bound Trace Metals in the White Rock Creek Watershed, Dallas and Collin Counties." Thesis, University of North Texas, 1990. https://digital.library.unt.edu/ark:/67531/metadc500728/.
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Areas were sampled in the White Rock Creek Watershed to examine sediment bound trace metal distributions and sorption relationships. A Kruskal-Wallis AOV found significant among area differences for most metals, and SNK-like multiple comparisons were used to group these areas. Kruskal-Wallis AOVs similarly found among area differences for sediment components that bind trace metals (Fe and Mn oxides and organic carbon) and physicochemical conditions that influence metal sorption (particle size and pH). Multiple correlation found numerous relationships among trace metals, sediment components, and physicochemical conditions. Statistical relationships indicate that metal partitioning to various sorption factors is metal specific. White Rock Creek Watershed trace metal concentrations are comparable to those in many urban watersheds.
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Boukider, Akli. "Conception des pompes centrifuges assistée par ordinateur dimensionnement et trace, optimisation du profil méridien /." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37612191g.
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Valette, Olivier. "Contribution à l'amélioration de la résolution double trace du détecteur à grand angle solide Diogène." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb37601694f.
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Sandelin, Kristoffer. "Chemical equilibrium studies on trace elements and on two process problems in solid fuel combustion /." Åbo : Åbo akademi university, 2002. http://catalogue.bnf.fr/ark:/12148/cb40124384q.
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Labou, Ibrahima. "Les complexes mafiques et ultramafiques birimiens de la ceinture de Mako (Sénégal oriental) témoins d'une évolution d'un domaine intra-océanique vers un domaine d'arc insulaire." Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30306.
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Les données isotopiques et en éléments en traces sur roches et minéraux de la région de Mako au Sénégal, mettent en évidence l'existence au sein de la croûte birimienne de roches magmatiques diversement différenciées (de cumulats ultramafiques à rhyolite) provenant de trois sources magmatiques parfaitement identifiées : une source déprimée plus juvénile à l'origine de la lignée tholéiitique 1 ; une source faiblement enrichie à l'origine de la lignée tholéiitique 2 et une source très enrichie dont est issue la lignée calco-alcaline. On peut ainsi proposer pour le groupe de Mako l'évolution géodynamique suivante : i) ouverture d'un océan entrainant la mise en place des roches de la lignée tholéiitique 1 au niveau d'une dorsale océanique, ces dernières ayant des caractéristiques proches des MORB ; ii) subduction intra-océanique induisant un magmatisme conduisant à la formation d'un arc insulaire immature qui se caractérise par un magmatisme tholéiitique dont les roches de la lignée tholéiitique 2 seraient les témoins ; iii) maturation de l'arc insulaire et mise en place des roches de la lignée calco-alcaline liée à l'enfoncement de la plaque plongeante et à l'épaississement de la partie crustale de l'arc<br>The isotopic and trace element data on rocks and minerals in the Birimian Mako region of Senegal reveal the existence of variously differentiated magmatic rocks (from ultramafic to rhyolite cumulates) from three perfectly identified magmatic sources: a more juvenile depleted source at the origin of the tholeiitic series 1; a weakly enriched source at the origin of the tholeiitic series 2 and a highly enriched source from which the calc-alkaline series originates. We can thus propose for the Mako group the following geodynamic evolution: i) opening of an ocean resulting in the emplacement of the rocks of the tholeiitic series 1 in the setting of an oceanic ridge, the rocks having characteristics close to the MORB ; ii) intra-oceanic subduction inducing magmatism leading to the formation of an immature insular arc which is characterized by a tholeiitic magmatism represented by the tholeiitic series 2; iii) Maturation of the insular arc and emplacement of rocks of the calc-alkaline series related to the subduction of the plate and thickening of the crustal portion of the arc
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Roell, Jennifer L. "Geochemical evidence for incremental emplacement of Palms pluton, southern California." Thesis, Connect to resource online, 2009. http://hdl.handle.net/1805/2061.
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Thesis (M.S.)--Indiana University, 2009.<br>Title from screen (viewed on February 2, 2010). Department of Earth Sciences, Indiana University-Purdue University Indianapolis (IUPUI). Advisor(s): Andrew P. Barth, Gabriel M. Filippelli, Kathy Licht. Includes vitae. Includes bibliographical references (leaves 102-110).
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Smith, Debra Walker. "The scales are still unbalanced : a phenomenological study of parental involvement of lower socioeconomic students attending school in an affluent Southeastern educational community /." Birmingham, Ala. : University of Alabama at Birmingham, 2007. https://www.mhsl.uab.edu/dt/2008r/smith.pdf.
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Thesis (Ph. D.)--University of Alabama at Birmingham, 2007.<br>Additional advisors: Lois M. Christensen, Lynn D. Kirkland, Maryann Manning, Dorothy Riley. Description based on contents viewed June 12, 2008; title from title screen. Includes bibliographical references (p. 121-126).
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Jeanrond, Werner G. "Text und Interpretation als Kategorien theologischen Denkens /." Tübingen : J.C.B. Mohr, 1986. http://catalogue.bnf.fr/ark:/12148/cb34935629p.
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Otava, Lukáš. "Firmware pro robotické vozítko." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220069.
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This thesis is focused on a firmware for robotic vehicle based on the ARM Cortex-M3 architecture that is running a real-time operating system (RTOS). Theoretical part describes available solutions of embedded RTOS and concrete HW implementation of the robotic vehicle. There is also comparison of the three selected RTOS with their measurements. Result of this thesis is base firmware compounded by a program modules that controls HW parts. There is also a sample PC and firmware application that extends base firmware. This sample application is able to communicate with robotic vehicle, control wheel motion and measure process data.
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Ledbetter, Nicole. "Applications of Nanomanipulation Coupled to Nanospray Mass Spectrometry in Trace Fiber Analysis and Cellular Lipid Analysis." Thesis, University of North Texas, 2008. https://digital.library.unt.edu/ark:/67531/metadc9760/.
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The novel instrumentation of nanomanipulation coupled to nanospray mass spectrometry and its applications are presented. The nanomanipulator has the resolution of 10nm step sizes allowing for specific fine movement used to probe and characterize objects of interest. Nanospray mass spectrometry only needs a minimum sample volume of 300nl and a minimum sample size of 300attograms to analyze an analyte making it the ideal instrument to couple to nanomanipulation. The nanomanipulator is mounted to an inverted microscope and consists of 4 nano-positioners; these nano-positioners hold end-effectors and other tools used for manipulation. This original coupling has been used to enhance the current abilities of cellular probing and trace fiber analysis. Experiments have been performed to demonstrate the functionality of this instrument and its capabilities. Histidine and caffeine have been sampled directly from single fibers and analyzed. Lipid bodies from cotton seeds have been sampled indirectly and analyzed. The few applications demonstrated are only the beginning of nanomanipulation coupled to nanospray mass spectrometry and the possible applications are numerous especially with the ability to design and fabricate new end-effectors with unique abilities. Future study will be done to further the applications in direct cellular probing including toxicology studies and organelle analysis of single cells. Further studies will be directed in forensic applications of this instrument including gunshot residue sampled from fibers.
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Dalou, Célia. "Fluorine and chlorine fractionation in the sub-arc mantle : an experimental investigation." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2011. http://tel.archives-ouvertes.fr/tel-00657297.
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Volatile elements released from the subducting slab play a fundamental role during the formation of arc magmas in the mantle wedge. Advances of melt inclusion studies enlarged the data on volatile abundance in arc magmas, and it is now possible to characterize some volatile contents in arc primary magmas, in particular F and Cl. A recent study of Mt Shasta melt inclusions (LeVoyer et al., 2010) shows that fractionation of F and Cl potentially contains information about arc magma genesis. In order to trace the source of arc magmas, fluorine and chlorine partitioning was investigated. Here, I present new experimental determinations of Cl and F partition coefficients between dry and hydrous silicate melts and mantle minerals: olivine, orthopyroxene, clinopyroxene, plagioclase, garnet and also pargasite and phlogopite. The values were compiled from more than 300 measurements in 24 melting experiments, conducted between 8 and 25 kbars and between 1180 and 1430˚C. The low abundance F, Cl measurements in minerals were done by Cameca IMF 1280 at WHOI using the negative secondary ion mode. The results show that DOpx/meltF ranges from 0.123 to 0.021 and DCpx/meltF ranges from 0.153 to 0.083, while Cl partition coefficient varies from DOpx/meltCl from 0.002 to 0.069 and DCpx/meltCfrom 0.008 to 0.015, as well. Furthermore, DOl/meltF ranges from 0.116 to 0.005 and DOl/meltCl from 0.001 to 0.004; DGrt/meltF ranges from 0.012 to 0.166 and DGrt/meltCl from 0.003 to 0.087 with the increasing water amount and decreasing temperature. I also show that F is compatible in phlogopite DPhl/meltF > 1.2) while DAmp/meltF is incompatible in pargasite DAmp/meltF from 0.36 to 0.63). On the contrary, Cl is more incompatible in phlogopite (DPhl/meltCl > 1.2 on average 0.09 ± 0.02), than in pargasite (DPhl/meltCl from 0.12 to 0.38). This study demonstrates that F and Cl are substituted in specific oxygen site in minerals that lead then to be more sensitive than trace elements to crystal chemistry and water amount variations thus melting conditions. Using those new partition coefficients, I modelled melting of potential sub-arc lithologies with variable quantity aqueous-fluid. This model is able to decipher 1) amount of aqueous-fluid involved in melting, 2) melting induced by fluid or melting of an hydrous mineral-bearing source and 3) melting of either pargasite-bearing lithology or phlogopite-bearing lithology and shows that sources of some primitive melts, for instance from Italy, bear pargasite and phlogopite, while some primitve melts seem to be the results of fluid-induced melts.
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Nnaji, Chinyere. "Analysis of Trace Amounts of Adulterants Found in Powders/Supplements Utilizing Direct Inject, Nanomanipulation, and Mass Spectrometry." Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc862761/.
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The regulations of many food products in the United States have been made and followed very well but unfortunately some products are not put under such rigorous standards as others. This leads to products being sold, that are thought to be healthy, but in reality contain unknown ingredients that may be hazardous to the consumers. With the use of several instrumentations and techniques the detection, characterization and identification of these unknown contaminates can be determined. Both the AZ-100 and the TE2000 inverted microscope were used for visual characterizations, image collection and to help guide the extraction. Direct analyte-probed nanoextraction (DAPNe) technique and nanospray ionization mass spectrometry (NSI-MS) was the technique used for examination and identification of all adulterants. A Raman imaging technique was than introduced and has proven to be a rapid, non-destructive and distinctive way to localize a specific adulterant. By compiling these techniques then applying them to the FDA supplied test samples three major adulterants were detected and identified.
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Vries, Catharina Maria de. "In the tracks of a lexicographer : secondary documentation in Samuel Johnson's "Dictionary of the English language", 1755... /." Leiden : Utrecht : [s.n.] ; LEd, 1994. http://catalogue.bnf.fr/ark:/12148/cb37645520d.
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Ramanantsizehena, Georgette. "Spectroscopie alpha appliquée à la recherche d'éléments trace et à l'identification de noyaux produits par réaction nucléaire." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb376006272.
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Berger, Gilles. "Etude expérimentale des premiers stades de l'altération hydrothermale de verres basaltiques et d'olivines comportement des éléments en trace /." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37602928q.
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Coates, Peter F. (Peter Francis). "Post Time." Thesis, University of North Texas, 1997. https://digital.library.unt.edu/ark:/67531/metadc278819/.
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Post Time is a non-fiction video program depicting some of the careers found at North American horse race tracks. Through the use of videotaped footage taken at eight race tracks and three training farms, the horse racing industry's trainers, jockeys, owners and grooms are profiled in the world they call the backstretch. The video begins with a brief history of horse racing and the origins of thoroughbred horses followed by closer examinations of the economic and social experiences faced by the owners, trainers, jockeys, and grooms as they attempt to prepare horses for racing every week.
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Wallace, Nicole. "Forensic Science Applications Utilizing Nanomanipulation-Coupled to Nanospray Ionization-Mass Spectrometry for the Analysis of Ultra-Trace Illicit Drugs." Thesis, University of North Texas, 2010. https://digital.library.unt.edu/ark:/67531/metadc33209/.
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Presented in this thesis are two methods that are coupled to the instrumentation for the recovery and analysis of ultra-trace illicit drug residues. The electrostatic dust lifting process is coupled with nanomanipulation-nanospray ionization to retrieve drug particles off of hard surfaces for analysis. For the second method, drug residues from fingerprint impressions are extracted followed by analysis. The methodology of these hyphenated techniques toward forensic science applications is applied as to explore limits of detection, sensitivity, and selectivity of analytes as well as immediacy and efficiency of analysis. The application of nanomanipulation-coupled to nanospray ionization-mass spectrometry toward forensic science based applications is considered as future improvements to trace and ultra-trace analysis.