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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.
41

Investigating Molecular Structures: Rapidly Examining Molecular Fingerprints Through Fast Passage Broadband Fourier Transform Microwave Spectroscopy

Grubbs, Garry Smith, II 05 1900 (has links)
Microwave spectroscopy is a gas phase technique typically geared toward measuring the rotational transitions of Molecules. The information contained in this type of spectroscopy pertains to a molecules structure, both geometric and electronic, which give insight into a molecule's chemistry. Typically this type of spectroscopy is high resolution, but narrowband ≤1 MHz in frequency. This is achieved by tuning a cavity, exciting a molecule with electromagnetic radiation in the microwave region, turning the electromagnetic radiation o, and measuring a signal from the molecular relaxation in the form of a free induction decay (FID). The FID is then Fourier transformed to give a frequency of the transition. "Fast passage" is defined as a sweeping of frequencies through a transition at a time much shorter (≤10 s) than the molecular relaxation (≈100 s). Recent advancements in technology have allowed for the creation of these fast frequency sweeps, known as "chirps", which allow for broadband capabilities. This work presents the design, construction, and implementation of one such novel, high-resolution microwave spectrometer with broadband capabilities. The manuscript also provides the theory, technique, and motivations behind building of such an instrument. In this manuscript it is demonstrated that, although a gas phase technique, solids, liquids, and transient species may be studied with the spectrometer with high sensitivity, making it a viable option for many molecules wanting to be rotationally studied. The spectrometer has a relative correct intensity feature that, when coupled with theory, may ease the difficulty in transition assignment and facilitate dynamic chemical studies of the experiment. Molecules studied on this spectrometer have, in turn, been analyzed and assigned using common rotational spectroscopic analysis. Detailed theory on the analysis of these molecules has been provided. Structural parameters such as rotational constants and centrifugal distortion constants have been determined and reported for most molecules in the document. Where possible, comparisons have been made amongst groups of similar molecules to try and get insight into the nature of the bonds those molecules are forming. This has been achieved the the comparisons of nuclear electric quadrupole and nuclear magnetic coupling constants, and the results therein have been determined and reported.
42

Le cautionnement dans le monde romain du IIe siècle av. J.-C. au Ier siècle ap. J.-C. / The caution money in the Roman world from the IInd century BC to Ist century AD

Chemain, Jean-François 06 February 2012 (has links)
La thèse de Jean-François Chemain porte sur « le cautionnement dans le monde romain du IIe siècle av. J.-C. au Ier siècle ap. J.-C. ». Elle a été menée à partir de sources littéraires, juridiques et épigraphiques. Dans sa première partie, l’auteur étudie les acteurs du cautionnement (garants et garantis) à la fin de la République : les relations qu’ils entretenaient les uns avec les autres, la catégorie sociale à laquelle ils appartenaient, les motifs qu’on avait de se porter caution, et les stratégies que cela pouvait dissimuler. Dans la deuxième partie, il repose la question des 5 leges de sponsu (lex Publilia, lex Appuleia, lex Furia, lex Cicereia, lex Cornelia), essayant, à partir de leur logique propre, de reconstituer les objectifs du législateur et, partant, de les dater. C’est ainsi qu’il situe la première dans un « long deuxième siècle avant J.-C. », peut-être à l’époque des Gracques, et les quatre dernières entre 67 et 47 av. J.-C. La troisième partie de la thèse est consacrée au devenir du cautionnement au début du Principat, marqué par une visible tentative d’en encadrer (apparition de la fideiussio) et limiter l’usage (préférence pour les garanties réelles, limitation des occasions de cautionner). Dans la quatrième partie, enfin, Jean-François Chemain met évidence que le cautionnement est un bon marqueur des grandes évolutions de la société romaine à l’époque du « Passage ». / Jean-François Chemain's thesis carries " the caution money in the Roman world of the IIth century BC in Ier century AD ". It was led from literary, legal and epigraphic sources. In his first part, the author studies the actors of the caution money (guarantors and guarantee) at the end of the Republic: the relations that they maintained some with the others, the social category to which they belonged, the motives which they had to stand surety, and the strategies which it could hide. In the second part, he asks the questionof the 5 leges de sponsu (lex Publilia, lex Appuleia, lex Furia, lex Cicereia, lex Cornelia), trying, from their own logic, to reconstitute the objectives of the legislator and therefore, to date them. And so he places the first one in a " long second century BC " Maybe at the time of Gracques, and the four last ones between 67 and 47 BC The third part of the thesis is dedicated to the future of the caution money at the beginning of the Princedom, marked by a visible attempt to frame( it (appearance of the fideiussio) and to limit its usage (preference for the real guarantees, the limitation of the opportunities to guarantee). In the fourth part, finally, Jean-François Chemain puts evidence that the caution money is a good marker of the main evolutions of the Roman society at the time of the "Passage".
43

Selling "Operation Passage to Freedom": Dr. Thomas Dooley and the Religious Overtones of Early American Involvement in Vietnam

Johnson, David Patrick 15 May 2009 (has links)
Vietnam was partitioned at the 17th parallel on 21 July 1954 with the signing of the Geneva Accords. During the following three hundred days, between 600,000 and one million Vietnamese civilians traveled from North Vietnam to South Vietnam. Three hundred thousand of these individuals were transported in the United States Navy's evacuation efforts, dubbed Operation Passage to Freedom. The Navy recognized the propaganda value of the evacuation from areas under communist control, but American audiences did not respond to the coverage afforded to the American operation. In 1956, a year after the completion of the evacuation, Dr. Thomas Dooley released Deliver Us from Evil, a first-hand account of his own experiences in Vietnam during the evacuation. This book enjoyed literary success and became a bestseller. This study explores the reasons Dooley enjoyed propagandistic success while other pieces of propaganda failed to sustain American interest.
44

"Too Little to Live and Too Much to Die" The Burgenländers' Immigration to the United States During the Interwar Period

Strobl, Philipp 17 December 2010 (has links)
This paper explores the history of a group of immigrants that came to the United States from the small rural Austrian region of the Burgenland between World War One and World War Two. By examining several biographical life stories of contemporaries it wants explain why the emigrants decided to leave their country, how they managed their passage, how they assimilated to their adopted‐home, and how they integrated themselves into the new society.
45

Building cohesion among Bakgatla male adolescents: a performance as research approach

Paya, Tefo Omphile 01 August 2012 (has links)
M.A. University of the Witwatersrand, Faculty of Humanities (Dramatic Art), 2011. / This practice led research explores masculine identity construction among young Bakgatla men. The research consists of a process-orientated performance intervention and a written component. I worked with a small group of young men of the Bakgatla tribe in the village of Mochudi, Botswana. Together we explored Masculine Identity, rites of passage and what it means to be a man within their community. This report begins within an introduction that frames the study. Then it proceeds in episodes until the overall conclusion. The first episode gives further context of the study by explaining the problem statement and rationale. Then the second episode goes on to give the aims of the study and how it was originally planned before commencement. In the third episode I discuss the theory relevant to my field of study. The following episode then goes into the pragmatics of the research and the analysis of key findings. The last episode I foreground my findings and the limitations of my study and suggest a possible way forward. The method of research used is practise-based research and the problemsthe study addresses are those of ethics versus aesthetics when applying theatre to a community setting and also the issue of the young men of the Bakgatla tribe being marginalised when it comes to dealing with issues about them. The practice led research demonstrated how a facilitator can use heightened performance effectively as a way of mirroring and deepening community-based interventions. Evidence was found that such a method could be more effective in finding a balance between ethics and aesthetics, resolving an on-going problem in other applied theatre methods that use performance processes of personal narratives to assist individuals and groups. This study also foregrounds knowledge about young men of the Bakgatla tribe and conclude that they should be given a space, similar to the kgotla, to confront and dialogue problems that face men in a contemporary Botswana.
46

Développement de nanoparticules composites polymériques de S-nitrosoglutathion dédiés au traitement oral des maladies cardiovasculaires / Development of polymer nanocomposites for the oral delivery of S-nitrosoglutathione devoted to cardiovascular disease treatment

Wu, Wen 14 October 2015 (has links)
Le S-nitrosoglutathion (GSNO), donneur d’oxyde nitrique (NO) physiologique, présente une application potentielle dans le traitement des maladies cardiovasculaires (CVD). Cependant, avec une demi vie supérieure à celle de NO, GSNO reste labile limitant ainsi son application. Cette étude vise au développement de particules nanocomposites (NCP) incluant des nanoparticules polymériques chargées en GSNO (GSNO-NP) dans une matrice polysaccharidique pour la voie orale. Bien que les GSNO-NP encapsulant efficacement GSNO, le libèrent rapidement in vitro, elles retardent la S-nitrosation (biomarqueur de NO) des protéines de cellules musculaires lisses en culture (18 h). Par conséquent, pour une libération prolongée, les GSNO-NP ont été incluses dans une matrice d’alginate (a), chitosan (c) ou un mélange des deux (acNCP). Les GSNO-acNCP avec une encapsulation élevée (76%) et une libération in vitro jusqu’à 24 h, ont significativement favorisé le passage de GSNO au travers d’un modèle de barrière intestinale (Caco-2). A la lumière de cette compatibilité avec un traitement oral journalier, le gavage de rats Wistar avec ces GSNO-acNCP 17 h avant prélèvement de l’aorte a diminué la contraction maximale phényléphrine (PHE) dépendante d’anneaux aortiques isolés. De plus, la N-acétylcystéine (NAC) (thiol déstockant NO tissulaire) produit la relaxation d’anneaux précontractés avec la PHE, prouvant le stockage de NO au sein de la paroi vasculaire. En augmentant le temps de résidence gastrointestinale et donc le passage de GSNO au travers de l’intestin, les GSNO-acNCP produisent un effet prolongé (17 h après administration) par l’intermédiaire du stockage de NO au niveau tissulaire / As a physiologic nitric oxide (NO) donor, S-nitrosoglutathione (GSNO) has potential therapeutic application for the treatment of cardiovascular disease (CVD). With a longer in vivo half-life than NO, GSNO is still sensitive to many factors leading to poor applicability. This study aimed at the development of nanocomposite particles (NCP) based on synthetic polymeric nanoparticles encapsulating GSNO (GSNO-NP) embedded in a polysaccharidic matrix for oral delivery of GSNO. Although GSNO-NP, with a high encapsulation efficiency, showed an in vitro burst release, they succeeded in the preservation of GSNO stability and bioavailability for smooth muscle cells as they delayed in vitro protein S-nitrosation (NO biomarker) until 18 h. Therefore, to reach the sustained release, GSNO-NP were embedded in a matrix of alginate (a), chitosan (c) or a blend (acNCP). GSNO-acNCP with high encapsulation efficiency (76%) and an in vitro release until 24 h, promoted the highest permeation rate of GSNO through an intestinal barrier model (Caco-2). With this daily oral treatment compatibility Wistar Rat pretreatment by gavage with GSNO-acNCP 17 h before aorta removal decreased the maximal contractile effect induced by phenylephrine (PHE) on isolated aortic rings. Furthermore, the N-acetylcysteine (a thiol displacing NO stores from tissues) produced the relaxation of PHE precontracted aortic rings, proving NO storage in the vessel wall. By increasing the residence time in the gastrointestinal tract thus promoting GSNO crossing through the intestinal barrier, GSNO-acNCP induced a long lasting effect (17 h after administration) through NO storage in vessels
47

Evaluation of Bar Rack Designs to Allow for the Downstream Passage of Silver American Eels at Hydropower Facilities

Melong, Tresha K 27 January 2014 (has links)
Concerns regarding the decreasing population of the American eel (reported by Castonguay et al. 1994; Haro et al. 2000) have led to design restrictions for hydropower facilities in the Eastern United States. However, the effects of these restrictions on eel passage and their impacts on power generation have not been fully researched. The goal of this study was to evaluate design parameters for bar racks that have potential to prevent entrainment of silver American eels, but also have minimal impacts on power generation. Hydraulic and biological assessments were used to determine the role of bar spacing, rack angle, and approach velocity on head loss across bar racks and the effects of bar spacing and approach velocity on eel bypass efficiency. The hydraulic assessments included computational fluid dynamics (CFD) analyses and laboratory experiments conducted in a re-circulatory flume at Alden Research Laboratory (Alden) in Holden MA. The flume allowed for determination of head losses across bar racks placed at angles of 45 and 90 degrees to the flow direction, with bar spacings of 0.75, 1.0 and 1.5 inches (19, 25 and 38 mm) and approach velocities of 1.5, 2.0 and 2.5 ft/sec (0.46, 0.61 and 0.76 m/s). Biological assessment, supported by funding from the Electric Power Research Institute (EPRI), used the same flume and included experiments with a 90 degree rack angle, bar spacings of 0.75 and 1.0 inches (19 and 25 mm), and approach velocities of 1.5 and 2.0 ft/sec (0.46 and 0.61 m/s). Bypass efficiencies, defined by the percentage of eels moving through the bypass, were evaluated for eels using three 2-hour replicate trials with nighttime releases of 30 eels per trial. Eel behavior in the vicinity of the racks was observed to the extent possible using a DIDSON acoustic camera. Experiments for the 90 degree configuration showed that the guidance efficiencies for the 0.75 inch (19 mm) spacing were greater than those for the 1.0 inch (25 mm) spacing, while the head losses for the 0.75 inch (19 mm) spacing exceeded the head losses for the 1.0 inch (25 mm) spacing by more than 10 percent. Linear regression analysis indicated that 53 percent of the variations in head width are explained by changes in the length of the eel. Results of the hydraulic evaluations were used to develop a new head loss equation that has a correlation coefficient of 98.6 percent. The results of the hydraulic and biological assessments provide a basis for quantifying the impacts of bar rack design on hydropower operation and downstream passage for American eels.
48

Passage Retrieval : en litteraturstudie av ett forskningsområde inom information retrieval / Passage Retrieval : a study of a research topic in information retrieval

Åkesson, Mattias January 2000 (has links)
The aim of this thesis is to describe passage retrieval (PR), with basis in results from various empirical experiments, and to critically investigate different approaches in PR. The main questions to be answered in the thesis are: (1) What characterizes PR? (2) What approaches have been proposed? (3) How well do the approaches work in experimental information retrieval (IR)? PR is a research topic in information retrieval, which instead of retrieving the fulltext of documents, that can lead to information overload for the user, tries to retrieve the most relevant passages in the documents. This technique was investigated studying a number of central articles in the research field. PR can be divided into three different types of approaches based on the segmentation of the documents. First, you can divide the text considering the semantics and where the topics change. Second, you can divide the text based on the explicit structure of the documents, with help from e.g. a markup language like SGML. And third, you can do a form of PR, where you divide the text in parts containing a fixed number of words. This method is called unmotivated segmentation. The study showed that an unmotivated segmentation resulted in the best retrieval effectiveness even though the results are difficult to compare because of different kinds of evaluation methods and different types of test collections. A combination between full text retrieval and PR also showed improved results. / Uppsatsnivå: D
49

Recherches sur les cistes prénestines. Approche pluridisciplinaire de petits et moyens conteneurs cylindriques et de leurs représentations en Italie centrale (470-270 avant J.-C) / Resarch on Praenestine Cistae. A Multidisciplinary approach to small and medium-sized cylindrical containers and their representations (420-270 B.C.)

Prieto-Luley, Laëtitia 06 April 2018 (has links)
Source de fantasme depuis le XVIIIe siècle, la question de la fonction des cistes prénestines reste ouverte comme le suggèrent des études récentes. Cette étude en propose une réévaluation. Elle revient sur un écueil méthodologique important qui consiste à traiter les cistes prénestines comme une catégorie homogène et à usage unique. Des considérations typologiques, iconographiques, iconologiques et historiques nous permettent d’approfondir le rôle pratique et symbolique des cistes. La réalisation d’une typologie des conteneurs affirme ainsi leurs potentialités d’usage et la diversité sociale et ethnique des propriétaires. L’approche iconique permet, quant à elle, de confirmer le rapport des cistes au passage. De nombreuses images témoignent d’une association d’idée entre cistes, beauté et mort. Cette relation s’exprime d’ailleurs à travers un langage funeste et eschatologique raffiné gravé sur les cistes. Pour reprendre le schéma d’A. Maslow, les cistes répondaient à cinq besoins fondamentaux : physiologique (usage lors de la toilette et des rituels), de sécurité (protection d’une classe d’âge), d’appartenance (bien élitiste), de reconnaissance (beauté maîtrisée) et de réalisation de soi (culture hellénique). / A source of imagination since the l8thcentury, the question of the use of Praenestine cistae remains an open one, as recent studies have suggested. This thesis proposes a reevaluation of the question by moving beyond the methodological stumbling block that has treated the Praenestine cistae as if they were a homogeneous category of objects with a single usage. A combination of typological, iconographic, iconological, and historical considerations allows us to deepen our understanding of the practical and symbolic role of these cistae. The creation of a typology of these containers thus affirms the possibilities for their use and the social and ethnic diversity of their owners. An iconic approach allows us to confirm the relationship of the cistae with rites of passage. Numerous images attest to a conceptual association between the cistae, beauty, and death. This relationship is expressed furthermore through a refined language relating to death and eschatological matters that is engraved on the cistae. Employing the schema of A. Maslow, the cistae correspond to five fundamental needs: psychological needs (usages relating to personal hygiene and rituals), the need for security (protection of a certain age grade), needs of belonging (an elite object), the need for recognition (the mastery of beauty), and the need for self-realization (Hellenic culture).
50

Chronik disorder

Davis, Sally, sallyjjdavis@bigpond.com January 2006 (has links)
The Chronik Disorder project consists of an exegesis and screenplay. The exegesis discusses research into the film genre, three-act structure, mythic structure and archetypes. The research then informed thematic ideas, character creation and a method for plotting the screenplay and developing the characters. Chronik Disorder is an Australian story, set in contemporary Melbourne, about adolescents and rites of passage. The story explores teenagers and the hip-hop subculture, gangs, graffiti and drug experimentation. The story deals with other issues such as vocational challenges; the breakdown of the nuclear family; father-and-son relationships; and Vietnam veterans and how the war affected them emotionally and impacted on their relationships with their sons. Harley, 17, a hooker in an under-eighteen's rugby union team, dreams of playing with the under-nineteen's Australian Wallabies. Harley's alcoholic father, Kev, takes out his pain caused by his experiences in Vietnam on Harley, who escapes by hanging out with graffiti-based gang Chronik Disorder. When his friend Damian dies, Harley blames himself, ruins his rugby career, and escapes by hanging out with his gang, committing crimes and taking drugs.

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