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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.
271

MHD Stability and Confinement of Plasmas in a Single Mirror Cell

Savenko, Natalia January 2006 (has links)
Thermonuclear fusion is a promising energy source for the future. If an economically efficient thermonuclear reactor would be built it has to be a cheap, safe, and highly productive electric power plant, or, a heating plant. The emphasis of this thesis is on the single cell mirror trap with a marginally stable minimum B vacuum magnetic field, the straight field line mirror field, which provides MHD stability of the system, absence of the radial drift even to the first order in plasma β , and a reduced magnetic flux tube ellipticity. Strong density depletion at the mirrors is proposed as a mean to build up a strong potential barrier for the electrons and thereby increase the electron temperature. Conditions to obtain an energy gain factor Q>10 are briefly analyzed. Current coils which could generate the derived magnetic field are proposed. A sloshing ion distribution function is constructed for the three dimensional ‘straight line mirror field’. The gyro centre Clebsch coordinates are found to be a new pair of motional invariants for this magnetic field. The gyro centre Clebsch coordinate invariants can be used to obtain complete solutions of the Vlasov equation, including the diamagnetic drift. These solutions show that the equilibria satisfy the locally omniginuity criterion to the first order in β . Contributions of the plasma diamagnetism to the magnetic flux tube ellipticity are studied for the straight field line mirror vacuum magnetic field and a sloshing ion distribution. Computations employing ray tracing have shown that there is a modest increase in the ellipticity, but the effect is small if β <0.2 . Adiabatic charged particle motion in general field geometry has been studied. A set of four independent stationary invariants, the energy, the magnetic moment, the radial drift invariant, and the bounce average parallel velocity is proposed to describe adiabatic equilibria.
272

Musiquer : plaidoyer évolutionniste transdisciplinaire

Campeau, Roxane 04 1900 (has links)
Le sujet prend appui sur une hypothèse : à l’origine, la musique est un phénomène culturel et biologique, social (et donc pas privé) et communautaire (et donc pas individuel). Les travaux de plusieurs théoriciens évolutionnistes du langage et/ou de la musique étayent l’hypothèse selon laquelle l’objet de la musique dépasse l’opposition nature-culture. Quelle est alors l’influence de ces caractéristiques sur l’apparition de la musicalité ou d’une faculté de musique ? Pour avancer dans notre réflexion, nous mesurons la contribution des recherches sur les amusies quant à la question des origines de la musique. Par la suite, nous étudions le rapport entre l’intentionnalité et l’évolution de la musique. Nous nous concentrons sur la nature sociale du phénomène musical, puis proposons l'intégration de la caractérisation biologique et sociale de la musique dans une conception institutionnelle et communautaire. Ainsi fondée philosophiquement, notre hypothèse de départ devient le véhicule du dépassement disciplinaire convoité. Enfin, certaines options proposées par différents auteurs décrivant la contribution de la musique au développement de réseaux neuronaux à la propriété miroir sont évoquées. Et nous tentons de répondre à cette question, inévitable : la musique peut-elle, étant donné son caractère irréductiblement culturel, social et communautaire, entretenir des connexions neuronales? Nous examinons notamment à cette fin les implications de la théorie du chaos et des résultats des simulations informatiques multi-agents. / The subject is based on an assumption: originally, the music is a cultural and a biological phenomenon, it is social (and not private) and institutional (and not individual). Several evolutionary theorists of language and/or music support the hypothesis that the purpose of language/music is beyond the opposition between nature and culture. Assuming those characteristics, then what is their influence on the development of musicality or of a faculty of music? To advance our thinking, we point out researches on the musical brain. Precisely, we evaluate the contribution of researches on amusia to the question of the origin of music. Subsequently, we study the relationship between intentionality and the evolution of music. Then, we focus on the social nature of the musical phenomenon, and propose to integrate social and biological characterization of music in a community and institutional conception. From then on, our assumption is philosophically founded and we assume that it can be an appropriate vehicle to exceed the disciplinary’s limits. Finally, we present some options proposed by different authors describing the contribution of music to the development of neural networks with a “mirror” property. Then, we try to answer this inevitable question: can music, given its irreducibly cultural, social and institutional characteristics, maintain neural connections? About this part, we examine the implications of chaos theory and the results of computer simulations.
273

Experiencing literature – learning from experience: the application of neuroscience to literary analysis by example of representations of German colonialism in Uwe Timm’s Morenga

Allen, Heather 08 September 2011 (has links)
Is it probable that a reader can have an empathetic and learning experience of an historical event facilitated through text? Research in neuroscience indicates that the form of a text can trigger mirror neurons, enhancing empathy with the events and characters portrayed and enabling introspective learning through stimulation of the default state network in a reading brain. Narrative elements in historical and fictional literature are analyzed for their potential in facilitating the stimulation of these states. The historical fiction novel Morenga by Uwe Timm is analyzed in order to deduce what a reader neurologically experiences in relation to the text and the historical event portrayed in the novel during the reading process. The probability of the reader experiencing empathy and learning through text so that their perspectives on inter-textual and extra-textual similar events are affected is then developed.
274

Kineziterapijos ir grįžtamojo ryšio poveikis fantominiams skausmams ir šlaunies raumenų jėgai po šlaunies amputacijos / The effect of physiotherapy and mirror therapy for phantom pain and thigh muscle force after transfemoral

Preimontaitė, Sigita 10 September 2013 (has links)
Tyrimo objektas: fantominio skausmo ir raumenų jėgos pokytis po kineziterapijos ir grįžtamojo ryšio. Tyrimo tikslas: įvertini kineziterapijos ir grįžtamojo ryšio poveikį fantominiams skausmams ir šlaunies raumenų jėgai po šlaunies amputacijos. Hipotezė: manome, kad taikant kineziterapiją ir grįžtamąjį ryšį po šlaunies amputacijos, fantominių skausmų intensyvumas sumažės ir šlaunies raumenų jėga padidės labiau, nei taikant kineziterapiją be grįžtamojo ryšio. Uždaviniai: 1. Palyginti fantominių skausmų intensyvumą ir šlaunies raumenų jėgą po šlaunies amputacijos kineziterapijos pradžioje ir po įprastinės be grįžtamojo ryšio kineziterapijos. 2. Palyginti fantominių skausmų intensyvumą ir šlaunies raumenų jėgą po šlaunies amputacijos kineziterapijos pradžioje ir po kineziterapijos kartu su grįžtamuoju ryšiu. 3. Palyginti įprastinės kineziterapijos ir kineziterapijos kartu su grįžtamuoju ryšiu poveikį fantominių skausmų intensyvumui ir šlaunies raumenų jėgai. Rezultatai: Tyrimo pradžioje, kontrolinės grupės tiriamieji fantominį skausmą įvertino 6,17±0,75, tiriamosios grupės tiriamieji – 6,83±0,75 balais. Tyrimo pabaigoje, kontrolinė grupė – 5,86±0,75, tiriamoji grupė – 5,17±0,75 balais. Prieš kineziterapiją kontrolinėje grupėje, po amputacijos, šlaunį tiesiančių raumenų jėga buvo 3,00±0,00, lenkiančių – 3,33±0,52, pritraukiančių – 2,83±0,51 ir atitraukiančių – 2,50±0,55 balų; tiriamojoje grupėje, šlaunį lenkiančių raumenų jėga buvo 3,17±0,47, tiesiančių – 3,00±0,00... [toliau žr. visą tekstą] / The object: effects of physiotherapy with mirror therapy for phantom pain and thigh muscle strength after transfemoral. The objective: the alteration of phant pain and thigh muscle after physiotherapy and mirror therapy. Hyptohesis: We consider, that the application of physiotherapy with mirror therapy helps to reduce phantom pain and improve muscle strenght better than physiotherapy without mirror therapy. The aims: 1. To compare phantom pain and muscle force in the beginning of physiotherapy and after physiothepy. 2. To compare phantom pain and muscle force in the beginning of physiotherapy and after physiotherapy with mirrot therapy. 3. To compare physiotherapy with mirror therapy and physiotherapy without mirror therpy for phantom pain and muscle force. Results: Beginning of the study, the control group subjects phantom pain score 6.17 ± 0.75, experimental group subjects - 6.83 ± 0.75 points. End of the study, the control group - 5.86 ± 0.75, experimental group - 5.17 ± 0.75 points. Before physical therapy in the control group after the amputation, the thigh muscle stretching force was 3.00 ± 0.00, flexion - 3.33 ± 0.52, attracting - 2.83 ± 0.51 and distracting - 2.50 ± 0.55 scores, the experimental group, the thigh, the muscle strength was 3.17 ± 0.47, stretching - 3.00±0.00, attracting - 2.67±0.47 and distracting-2.83±0.37 points. Application of physical therapy procedures, after 3 weeks, the control group, after the amputation, the thigh flexion strength was 4.33 ± 0... [to full text]
275

Experiencing literature – learning from experience: the application of neuroscience to literary analysis by example of representations of German colonialism in Uwe Timm’s Morenga

Allen, Heather 08 September 2011 (has links)
Is it probable that a reader can have an empathetic and learning experience of an historical event facilitated through text? Research in neuroscience indicates that the form of a text can trigger mirror neurons, enhancing empathy with the events and characters portrayed and enabling introspective learning through stimulation of the default state network in a reading brain. Narrative elements in historical and fictional literature are analyzed for their potential in facilitating the stimulation of these states. The historical fiction novel Morenga by Uwe Timm is analyzed in order to deduce what a reader neurologically experiences in relation to the text and the historical event portrayed in the novel during the reading process. The probability of the reader experiencing empathy and learning through text so that their perspectives on inter-textual and extra-textual similar events are affected is then developed.
276

Design and characterization of an optical tweezers system with adaptive optic control

Bowman, Shaun 23 December 2009 (has links)
The thesis details the design and characterization of an innovative optical tweezer system. Optical tweezers provide a relatively new technique for non-contact manipulation of micron-scale particles. They employ a laser beam to hold such particles at the laser’s focus. Optical tweezers are used for many scientific purposes, such as: measuring the mechanical properties of bio-molecules, cell and molecule sorting, stiction-less micro-manipulators, and fundamental research in physics. Typically, trap location has been controlled using steer-mirrors or spatial light modulators, operating without beam quality feedback. Here, an innovative trap control system has been developed, featuring a closed-loop adaptive optics system. The prototype system employs a deformable mirror and wavefront sensor to control trap position in three dimensions, while simultaneously removing beam aberrations. The performance of this system is investigated in terms of controllable range of trap motion, trap stiffness, and trap position stability.
277

An Investigation On Plasma Antennas

Tigrek, Recep Firat 01 August 2005 (has links) (PDF)
The plasma antennas offer a new solution to new requirements that are imposed on antenna systems with the advancing communication technology and increasing demand on wider frequency bands. In this thesis the plasma antennas are investigated for the radar and communication applications. The interaction of gas and semiconductor plasma with electromagnetic waves is inspected theoretically, and several experiments on the interaction of microwaves with gas plasma are conducted. Results of these experiments show that a relatively simple setup can produce plasma dense enough to interact with microwaves of frequency about 8 GHz. The previous studies of other institutes on plasma antennas are surveyed, emphasizing the results important for the use in radar and communication applications. Finally, semiconductor plasma is introduced, and an antenna system utilizing the semiconductor plasma generated by optical excitation is proposed.
278

O espelho de Glatzel na avaliação da permeabilidade nasal em adultos / The glatzel mirror in the assessment of nasal patency in adults

Brescovici, Silvana Maria January 2004 (has links)
Introdução O espelho de Glatzel (EG) é correntemente utilizado em consultórios fonoaudiológicos para a avaliação rápida da permeabilidade nasal. O mesmo foi descrito inicialmente em 1898 por Zwaardemaker. Porém, estudos de validação inexistem na literatura. Este estudo teve por objetivos verificar a reprodutibilidade do EG e a correlação intra-sujeito entre área de condensação e percepção subjetiva de permeabilidade nasal. Material e Métodos Vinte e cinco sujeitos foram avaliados com o EG por cinco minutos consecutivos (475 medidas por sujeito); cada meia hora por quatro horas; cada dia no início da tarde, por cinco dias e toda a quinta-feira por cinco semanas consecutivas. Utilizou-se uma escala análoga visual para avaliar a percepção de respiração nos períodos de horas, dias e semanas. Resultados O coeficiente de correlação total (área direita mais esquerda) encontrado entre área de condensação e percepção subjetiva foi de r=0,04 (p=0,3761). No lado esquerdo foi de r=0,08 (p=0,0984) e no lado direito de r=0,05 (p=0,2862). Os coeficientes de variação unilaterais medianos foram menores que 15% e os totais menores que 12%, independente do intervalo de tempo entre teste e re-teste. Conclusão Não se evidenciou correlação significativa entre a percepção subjetiva e a área de condensação nasal. A variabilidade unilateral foi maior do que quando considerados os valores totais (direito mais esquerdo) e não houve diferença na variabilidade das medidas de área de condensação nasal nos diferentes momentos do tempo. / Objective The Glatzel mirror (Gm) is used at speech therapy offices for a prompt evaluation of the nasal patency. It has been described in 1898 by Zwaardemarker. However, there is no literature of validation studies. This study aimed the verification of the reproducibility of the Gm and the correlation between the condensation area and the subjective perception of nasal patency. Methods Twenty-five individuals were evaluated for five consecutive minutes (475 measurements per individual), every half-an-hour during four hours, every day, in the beginning of the afternoon, for five days, and every Thursday during five consecutive weeks. A visual analog scale was used to evaluate the breathing perception within the hour, day and week periods. Results The coefficient of correlation between the subjective perception of the nasal patency and the condensation area of the right and left areas sumed was r=0.04 (p=0.3761). The left was r=0.08 (p=0.0984) and the right was r=0.05 (p=0.2862). The medium unilateral and total coefficients of variation were, respectivelly, less then 15% and 12%, independently of the interval of test-retest timing. Conclusion No significant correlation has been noticed between the subjective perception and the nasal condensation area. The unilateral variability was higher than the total values (right + left) and there was no difference in the variability of nasal condensation areas on different moments in time.
279

A imagem no espelho: o drama de uma ficção / The image in the mirror: the drama of a fiction

Ana Paula Rocha da Cunha 01 April 2014 (has links)
Esta dissertação se propõe a estudar o tema do duplo a partir da produção fílmica de Hanns Heinz Ewers, O estudante de Praga, e o conto de Mário de Sá-Carneiro, A confissão de Lúcio, ambos de 1913. Asduas narrativas se organizam em torno de um triângulo amoroso e compartilham o mesmo destino trágico. Tomando como suporte, inicial, de leitura os textos de Freud e Rank, de 1914, Sobre o narcisismo: uma introdução e O duplo, respectivamente, o artigo de Lacan, O estádio do espelho como formador da função do eu (1949) e seu seminário sobre a angústia, pretende-se estabelecer um diálogo entre literatura e psicanálise, considerando a questão do desdobramento do eu e suas variantes, a cisão do eu em múltiplos eus e o desaparecimento da imagem. A imagem no espelho, a princípio fonte de júbilo, escamoteia um drama: o drama de um sujeito que se constitui a partir de uma ficção / This dissertation proposes to study the theme of the double from the filmic production by author Hanns Heinz Ewers called The student of Prague, as well as Mário de Sá-Carneiros tale named Lúcios confession. Ewers and Sá-Carneiros works are both from 1913. These narratives are organized around a love triangle and share the same tragic fate. Taking as a starting-readable texts by authors Freud and Rank in 1914, called On narcissism: an introduction and The double respectively, Lacan s article, The Mirror Stage as formative of the function of the I (1949) and his seminar on anxiety, thus we intend to establish a dialogue between literature and psychoanalysis, considering the issue of deployment of the self and its variants, ego splitting into multiple selves and the disappearance of the image. The image in the mirror, originally source of joy, hides a drama: the drama of an individual who is built up from a fiction
280

O espelho de Glatzel na avaliação da permeabilidade nasal em adultos / The glatzel mirror in the assessment of nasal patency in adults

Brescovici, Silvana Maria January 2004 (has links)
Introdução O espelho de Glatzel (EG) é correntemente utilizado em consultórios fonoaudiológicos para a avaliação rápida da permeabilidade nasal. O mesmo foi descrito inicialmente em 1898 por Zwaardemaker. Porém, estudos de validação inexistem na literatura. Este estudo teve por objetivos verificar a reprodutibilidade do EG e a correlação intra-sujeito entre área de condensação e percepção subjetiva de permeabilidade nasal. Material e Métodos Vinte e cinco sujeitos foram avaliados com o EG por cinco minutos consecutivos (475 medidas por sujeito); cada meia hora por quatro horas; cada dia no início da tarde, por cinco dias e toda a quinta-feira por cinco semanas consecutivas. Utilizou-se uma escala análoga visual para avaliar a percepção de respiração nos períodos de horas, dias e semanas. Resultados O coeficiente de correlação total (área direita mais esquerda) encontrado entre área de condensação e percepção subjetiva foi de r=0,04 (p=0,3761). No lado esquerdo foi de r=0,08 (p=0,0984) e no lado direito de r=0,05 (p=0,2862). Os coeficientes de variação unilaterais medianos foram menores que 15% e os totais menores que 12%, independente do intervalo de tempo entre teste e re-teste. Conclusão Não se evidenciou correlação significativa entre a percepção subjetiva e a área de condensação nasal. A variabilidade unilateral foi maior do que quando considerados os valores totais (direito mais esquerdo) e não houve diferença na variabilidade das medidas de área de condensação nasal nos diferentes momentos do tempo. / Objective The Glatzel mirror (Gm) is used at speech therapy offices for a prompt evaluation of the nasal patency. It has been described in 1898 by Zwaardemarker. However, there is no literature of validation studies. This study aimed the verification of the reproducibility of the Gm and the correlation between the condensation area and the subjective perception of nasal patency. Methods Twenty-five individuals were evaluated for five consecutive minutes (475 measurements per individual), every half-an-hour during four hours, every day, in the beginning of the afternoon, for five days, and every Thursday during five consecutive weeks. A visual analog scale was used to evaluate the breathing perception within the hour, day and week periods. Results The coefficient of correlation between the subjective perception of the nasal patency and the condensation area of the right and left areas sumed was r=0.04 (p=0.3761). The left was r=0.08 (p=0.0984) and the right was r=0.05 (p=0.2862). The medium unilateral and total coefficients of variation were, respectivelly, less then 15% and 12%, independently of the interval of test-retest timing. Conclusion No significant correlation has been noticed between the subjective perception and the nasal condensation area. The unilateral variability was higher than the total values (right + left) and there was no difference in the variability of nasal condensation areas on different moments in time.

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