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Análise da interação universidade-empresa a partir das diferenças em instituições públicas de ensino superior no BrasilSilva, Fernanda Rocha Veras e January 2016 (has links)
Inovar no mundo moderno tornou-se crucial para o desenvolvimento econômico e social das nações. Diante disso, o conhecimento e a capacidade de aprendizado passaram a ser condições imprescindíveis, e cada vez mais dependentes das interações entre diferentes atores. Apesar da crescente preocupação com interação, no Brasil ainda existe pouca evidência científica do grau de heterogeneidade institucional e regional do ensino e pesquisa, e baixa compreensão das relações entre estrutura e resultados da pesquisa interativa. Além disso, os índices comumente usados que mensuram interação não revelam precisamente a complexidade do processo interativo. Nesse sentido, observe-se como o problema da pesquisa se conformou: - As medidas de interação comumente usadas são capazes de determinar e revelar a complexidade da interação das instituições de ensino e pesquisa no Brasil? - Suas estruturas têm, em geral, fraca correlação com seus resultados em função da heterogeneidade institucional e regional? Assim, o objetivo geral consistiu em analisar a interação a partir da diversidade institucional e regional das instituições de ensino e pesquisa do Brasil para o ano de 2010, com base nos dados do Diretório dos Grupos de Pesquisa do Conselho Nacional de Desenvolvimento Científico e Tecnológico (DGP/CNPq). Especificamente, os objetivos se constituíram em: analisar o grau de interação institucional com base nas medidas usadas na literatura brasileira; construir um índice de interação institucional que revele a diversidade do processo de interação das instituições; calcular correlações entre estruturas e resultados para instituições e regiões do Brasil; e aplicar uma survey para avaliação do caso de algumas universidades do País Os métodos e procedimentos da pesquisa foram: (1) Pesquisa exploratória com uso de dados secundários do CNPq, Geocapes e do Censo Educação Superior; (2) investigação sobre a realidade institucional e regional do ensino e pesquisa a partir de dados disponíveis no CNPq e em outras instituições que disponibilizam informações sobre o ensino superior no Brasil; (3) no uso de estatísticas descritivas para avaliar a heterogeneidade estrutural e de produção institucional e regional; (4) construção do Índice de Interação Diversificado (IID) como uma alternativa às medidas de interação em geral utilizadas, que incorpore a diversidade produtiva e de relacionamentos institucionais; (5) cálculo de correlações entre estrutura e resultados para determinar a diversidade de associações institucionais e regionais e; (6) aplicação de uma survey para caracterização in loco de quatorze universidades federais, definidas em amostra de trinta e seis observações de grupos de pesquisa nas áreas de ciências agrárias, da saúde e engenharias. Alguns dos principais resultados apontam: forte heterogeneidade estrutural e de resultados entre instituições interativas e regiões do País; o IID, índice criado, mostrou-se mais adequado na classificação das referidas instituições; as estruturas de recursos humanos de maior qualificação associaram-se melhor aos resultados da pesquisa, ensino e interação no Brasil, e, mesmo com os avanços neste processo de interação, ainda existem entraves, essencialmente burocráticos ao desenvolvimento das relações universidade-empresa. / In the modern world, innovation has become crucial to the economic and social development of nations. So much so that knowledge and the ability to learn are now essential conditions and ever more dependent of the interaction between various actors. Despite the increasing preoccupation with such interactions in Brazil, there is still little scientific evidence of the degree of institutional and regional heterogeneity in education and research, as well as a low understanding of the relations between structure and research results. Besides, the conventional indexes used to measure these interactions do not reveal accurately the complexity of such processes. In this sense, the problem poses the following questions: are the generally used measurements capable to determine and reveal the interaction complexity within learning and research institutions in Brazil? And, do the structures of such institutions have, in general, a weak correlation with its results due to an institutional and regional heterogeneity? This way, the general objective has been to analyze the interaction out of the institutional and regional diversity of the learning and research institutions of Brazil in 2010, based on data of the Directory Of Research Groups Of The National Council For Scientific and Technological Development (DGP/CNPq). Specifically, the objectives consisted in: analyze the degree of institutional interaction out of the conventional measures of Brazilian literature; to build an index of institutional interaction that reveals the process diversity of such interactions; calculate the correlations between structures and results for institutions and regions of Brazil and; to apply an evaluation survey on the case of some universities in the country The methods and procedures of the research were: (1) exploratory research with the use of secondary data from CNPq, Geocapes and the College Education Census; (2) investigation of the institutional and regional reality of education and research out of available data from CNPq, as well as other institutions that provide information about college education in Brazil; (3) the use of statistical descriptions to evaluate the structural and production heterogeneity, both institutional and regional; (4) the building of the Diversified Interaction Index (IID) as an alternative to the generally used measures of interaction that embody the productive diversity and institutional relations; (5) measurement of correlations between structure and results to determine the institutional and regional diversity of associations; (6) application of survey for in loco description of fourteen federal universities, defined in a sample of thirty-six research group’s observations in the fields of agricultural sciences, health and engineering. Some of the main results indicate: strong heterogeneity in structure, as well as in results, between interactive institutions and regions of the country; the created index IID has proven itself more adequate in the classification of referred institutions; human resources’ structures of greater qualification associated better with the results of research, education and interaction in Brazil; and, even with advances in the interaction process in the country, the obstacles to the development of the relations between university and enterprise, mainly bureaucratic, still persist.
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Vieillissement de matériaux composites renforcés de fibres naturelles : étude de l’impact sur les propriétés d’aspect et sur les émissions dans l’air intérieur / Weathering of natural fibers reinforced composites : study of the impact on aspect properties and emissions in indoor airBadji, Célia 06 December 2017 (has links)
Les biocomposites sont des matériaux renforcés de fibres issues de ressources renouvelables. Ces matériaux sont une solution alternative aux composites renforcés de fibres de verre ou de carbone. En effet, leur légèreté et leurs propriétés mécaniques intéressantes leur confèrent un intérêt grandissant dans les secteurs tels que la construction (terrasse, meubles de jardin) ou l’automobile (panneaux de porte, tableaux de bord). Toutefois, les milieux humides, la température et le rayonnement UV sont des paramètres pouvant compromettre la stabilité physico-chimique des biocomposites. L’objectif principal de cette thèse a été d’évaluer la durabilité des biocomposites sous leurs conditions d’usage principales. Pour cela, ces matériaux ont été exposés pendant une année à l’extérieur (lames de terrasse) et sous vitre pare-brise (tableaux de bord). Les résultats ont montré que, bien que la performance mécanique des biocomposites ait été affectée, celle-ci n’a pas été grandement influencée par le type d’exposition. Par contre, les différences de variations de couleur et de cristallinité différant entre les deux expositions suggèrent des mécanismes de dégradation différents et très dépendants des conditions d’usage.Puisque les biocomposites peuvent être utilisés dans des environnements clos tels que les habitacles d’automobile, ils peuvent être également des sources de polluants dans l’air intérieur. L’étude des émissions de composés organiques volatils (COV) par les biocomposites au cours de leur vieillissement sous vitre pare-brise, a permis de générer des données nécessaires à l’évaluation de l’impact sur la qualité de l’air intérieur de véhicule de ces nouveaux matériaux. Cependant, l’augmentation drastique de la concentration de surface en COV au cours du vieillissement suggère que l’exposition a fortement affecté les biocomposites à cause de la sensibilité des composants structurant les fibres végétales face aux conditions d’exposition.La compréhension des mécanismes de dégradation peut s’effectuer à travers l’interprétation des liens de causalité entre les propriétés mécaniques et de microstructure, les émissions de COV, et l’apparence visuelle. Un traitement statistique par analyse en composantes principales (ACP) a ainsi permis de dégager les relations entre les paramètres quantitatifs.Le vieillissement naturel nécessite souvent une durée d’exposition longue pour apercevoir une dégradation effective des matériaux. De ce fait, le vieillissement accéléré en enceinte de laboratoire est de plus en plus réalisé en industrie permettant un gain de temps. Afin de vérifier la représentativité des mécanismes de dégradation en environnement extérieur par l’enceinte, une étude comparative entre le vieillissement naturel extérieur et un vieillissement accéléré en enceinte a été menée. / Biocomposites are fiber-reinforced materials from renewable resources. These materials are an alternative to fiberglass or carbon reinforced composites. Indeed, their lightweight and interesting mechanical properties give them a growing interest in sectors such as building (decking, garden furniture) or automobile (door panels, dashboards). However, humidity, temperature and UV radiation are parameters that can compromise the physicochemical stability of biocomposites.The main objective of this thesis is to assess the biocomposites durability in their main conditions of use. For this purpose, these materials have been exposed for one year outdoors (deck boards) and under windshield glass (dashboards). The results showed that the mechanical performance of biocomposites was affected and greatly influenced by the type of exposure. On the other hand, the differences in color and crystallinity variations that differ between the two exposures suggest different degradation mechanisms that are very dependent on the conditions of use.Since biocomposites can be used in environments such as the passenger cabin, they can also be sources of pollutants in indoor air. The study of emissions of volatile organic compounds (VOCs) by biocomposites during their ageing under windshield glass allowed generating data necessary for the evaluation of the impact on the car indoor air quality of these new materials. However, the drastic increase of VOCs surface concentration during exposure suggests that weathering strongly affected biocomposites due to the sensitivity of the structural components of plant fibers to exposure conditions.Understanding of the degradation mechanisms can be carried out through the interpretation of the causal links between mechanical and microstructural properties, VOC emissions and visual appearance. Statistical treatment by Principal Component Analysis (PCA) revealed the links and relationships existing between the quantitative parameters.Natural weathering often requires long time of exposure for an efficient perception of the materials degradation. Thus, accelerated ageing in laboratory is more and more carried out in industry for time saving. In order to verify the representativeness of the degradation mechanisms occurring during exterior weathering by weathering chambers, a comparative study between the exterior aging and the artificial aging was carried out.
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Long-term tectonothermal history of Laramide basement from zircon–He age-eU correlationsOrme, Devon A., Guenthner, William R., Laskowski, Andrew K., Reiners, Peter W. 11 1900 (has links)
The long-term (>1 Ga) thermal histories of cratons are enigmatic, with geologic data providing only limited snapshots of their evolution. We use zircon (U-Th)/He (zircon He) thermochronology and age composition correlations to understand the Proterozoic-Phanerozoic thermal history of Archean Wyoming province rocks exposed in the northern Laramide ranges of western North America. Zircon He ages from the Wind River Range (54 dates) and Bighorn Mountains (32 dates) show negative correlations with effective uranium (eU), a proxy for radiation damage. Zircon dates from the Bighorns are between 960 Ma (low-eU) and 20 Ma (high-eU) whereas samples from the Wind Rivers are between 582 Ma (low-eU) and 33 Ma (high-eU). We applied forward modeling using the zircon radiation damage and annealing model ZrDAAM to understand this highly variable dataset. A long-term t-T path that is consistent with the available geologic constraints successfully reproduced age-eU correlations. The best fit to the Wind Rivers data involves two phases of rapid cooling at 1800-1600 Ma and 900-700 Ma followed by slower cooling until 525 Ma. During the Phanerozoic, these samples were heated to maximum temperatures between 160 and 125 degrees C prior to Laramide cooling to 50 degrees C between 60 and 40 Ma. Data from the Bighorn Mountains were successfully reproduced with a similar thermal history involving cooler Phanerozoic temperatures of similar to 115 degrees C and earlier Laramide cooling between 85 and 60 Ma. Our results indicate that age-eU correlations in zircon He datasets can be applied to extract long-term thermal histories that extend beyond the most recent cooling event. In addition, our results constrain the timing, magnitude and rates of cooling experienced by Archean Wyoming Province rocks between recognized deformation events, including the >1 Ga period represented by the regionally-extensive Great Unconformity.
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\"Implementação da técnica de correlações angulares perturbadas no laboratório Pelletron para estudo de estruturas e interações de biomoléculas\" / Implementation of The Perturbed Angular Correlations Technique at The Pelletron Laboratory for the Study of Biomolecules Structures and InteractionsJairo Cavalcante de Souza 13 February 2007 (has links)
Este trabalho de mestrado trata da implementação de um espectrômetro de correlações angulares perturbadas no Laboratório do Acelerador Pelletron do Instituto de Física da Universidade de São Paulo. O espectrômetro é formado por seis detectores cintiladores com cristais de \'BaF IND.2\', de 3 polegadas de diâmetro por 6 de comprimento, com um sistema eletrônico e de aquisição de dados multiparamétrico padrão CAMAC. Diferentemente do usual, os espectros de energia dos raios gama dos núcleos de prova são adquiridos para cada detector, o que permite manter um controle maior sobre todo o experimento. Além disso, um mesmo experimento pode ser revisto com diferentes abordagens por diversas vezes, pois todas as informações sobre ele são armazenadas. Com a configuração eletrônica adotada, os espectros de energia são obtidos por meio de um QDC (charge to digital converter), dispensando o uso de pré-amplificadores. Os espectros de tempo são adquiridos com um TDC (time do digital converter). A seleção dos eventos de coincidência é realizada computacionalmente, procedimento que pode ser realizado durante a aquisição dos dados. Como a motivação para a implementação desse espectrômetro é o estudo de estruturas e interações de biomoléculas por meio da técnica de correlações angulares (PAC), foram realizadas medidas exploratórias, com o uso do espectrômetro do Laboratório de interações Hiperfinas (LIH) do Centro do Reator de Pesquisas (CRPq) no IPEN, paralelamente à implementação do espectrômetro. As primeiras medições foram realizadas com amostras de vesículas lipídicas. Com essas medidas foi possível notar a influência da variação de tamanho das moléculas (diminuição de tamanho em uma ordem de grandeza) no tempo de correlação rotacional à temperatura ambiente, quando adicionado SDS (sodium dodecyl sulfate) na suspensão para formação de um agregado micelar. As duas séries de medidas seguintes foram realizadas com amostras de SDS nas quais variaram-se as concentrações para se tentar verificar alterações na geometria ou na mobilidade das moléculas em função desse parâmetro. Foi possível notar que o comportamento das funções perturbação experimentais variaram com as amostras, porém não foi possível notar sistemática no comportamtento. Outro fator notado foi a influência do meio. O comportamento das moléculas quando na presença de metanol nas amostras era bem diferente das soluções aquosas. Também não foi possível obter uma conclusão clara quanto à concentração micelar crítica para soluções aquosas. Por fim foram realizadas medidas com amostras de proteína calmodulina. Foram feitas medidas à temperatura ambiente e a 77K. Notou-se que essa proteína é passível de ser estudada por meio da técnica PAC. Para confirmar a presença da proteína nas amostras e também tentar verificar um deslocamento na massa devido à presença do íon \'ANTPOT.111 Cd\' \'ANTPOT.2+\' foram realizadas medidas de espectrometria de massas no Laboratório de Espectrometria de Massas na Embrapa em Brasília. Foi possível confirmar a presença da proteína nas amostras, porém não foi possível notar a presença de \'ANTPOT.111 Cd\' devido à baixa concentração de íons utilizados com a técnica PAC. / This work is related to the implementation of a perturbed angular correlation (PAC) spectrometer at the University of São Paulo Pelletron Laboratory. The spectrometer consists of 6 cylindrical BaF$_2$ scintillator detectors, with 3 inches diameter and 6 inches length and a multiparameter CAMAC data acquisition system. Different from usual, the gamma ray energy spectra of the cascade nuclei are acquired for each detector, which allows us to have more control of the experiment. Besides, the same experiment can be revised with different approaches at any time. With the adopted electronics configuration, the energy spectra are obtained through a QDC (charge to digital converter) module, which dispenses the use of pre-amplifiers. The time spectra are acquired with a TDC (time to digital converter) module. The selection of coincidence events is performed computationally, and this procedure can be evaluated during the data acquisition. The main motivation for implementing this spectrometer is the study of the structure and interactions of biomolecules through the perturbed angular correlation technique. Test measurements were performed, parallel to the spectrometer construction, with the use of the Hyperfine Interactions Laboratory spectrometer at the Centro do Reator de Pesquisas do Instituto de Pesquisas Energéticas e Nucleares (CRPq-IPEN). The first measurements were performed with lipidic vesicles samples. In this case it was possible to observe the influence of the molecule dimension change (decrease in one order) on the rotational correlation time at room temperature, when SDS (sodium dodecyl sulfate) was added in the suspension to form micellar aggregation. The two following series of measurements were performed with SDS samples in which the concentration was varied in order to verify modifications in the geometry or mobility of the molecules as a function of that parameter. The behavior of the experimental perturbation functions varied with the samples. However, it was not possible to point out any systematics in their behavior. The molecules behavior when in presence of methanol in the samples was very different from the aqueous solutions. Also, it was not possible to obtain a clear conclusion about the critical micellar concentration for the aqueous solutions. Finally, the last measurements were performed with calmodulin protein samples, at room temperature and at 77K. In this case we concluded that this protein can be studied through the PAC technique. In order to confirm the presence of the protein in the samples and at same time to verify if any mass displacement occurred due to the presence of the $^{111}$Cd$^{2+}$, mass spectrometry measurements were performed at the Laboratório de Espectrometria de Massas -- Embrapa in Brasília. It was possible to confirm the presence of the protein in the samples, but it was not possible to observe the mass displacement due to the presence of the $^{111}$Cd, since the ions concentration used with the PAC technique is very low.
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\"Implementação da técnica de correlações angulares perturbadas no laboratório Pelletron para estudo de estruturas e interações de biomoléculas\" / Implementation of The Perturbed Angular Correlations Technique at The Pelletron Laboratory for the Study of Biomolecules Structures and InteractionsSouza, Jairo Cavalcante de 13 February 2007 (has links)
Este trabalho de mestrado trata da implementação de um espectrômetro de correlações angulares perturbadas no Laboratório do Acelerador Pelletron do Instituto de Física da Universidade de São Paulo. O espectrômetro é formado por seis detectores cintiladores com cristais de \'BaF IND.2\', de 3 polegadas de diâmetro por 6 de comprimento, com um sistema eletrônico e de aquisição de dados multiparamétrico padrão CAMAC. Diferentemente do usual, os espectros de energia dos raios gama dos núcleos de prova são adquiridos para cada detector, o que permite manter um controle maior sobre todo o experimento. Além disso, um mesmo experimento pode ser revisto com diferentes abordagens por diversas vezes, pois todas as informações sobre ele são armazenadas. Com a configuração eletrônica adotada, os espectros de energia são obtidos por meio de um QDC (charge to digital converter), dispensando o uso de pré-amplificadores. Os espectros de tempo são adquiridos com um TDC (time do digital converter). A seleção dos eventos de coincidência é realizada computacionalmente, procedimento que pode ser realizado durante a aquisição dos dados. Como a motivação para a implementação desse espectrômetro é o estudo de estruturas e interações de biomoléculas por meio da técnica de correlações angulares (PAC), foram realizadas medidas exploratórias, com o uso do espectrômetro do Laboratório de interações Hiperfinas (LIH) do Centro do Reator de Pesquisas (CRPq) no IPEN, paralelamente à implementação do espectrômetro. As primeiras medições foram realizadas com amostras de vesículas lipídicas. Com essas medidas foi possível notar a influência da variação de tamanho das moléculas (diminuição de tamanho em uma ordem de grandeza) no tempo de correlação rotacional à temperatura ambiente, quando adicionado SDS (sodium dodecyl sulfate) na suspensão para formação de um agregado micelar. As duas séries de medidas seguintes foram realizadas com amostras de SDS nas quais variaram-se as concentrações para se tentar verificar alterações na geometria ou na mobilidade das moléculas em função desse parâmetro. Foi possível notar que o comportamento das funções perturbação experimentais variaram com as amostras, porém não foi possível notar sistemática no comportamtento. Outro fator notado foi a influência do meio. O comportamento das moléculas quando na presença de metanol nas amostras era bem diferente das soluções aquosas. Também não foi possível obter uma conclusão clara quanto à concentração micelar crítica para soluções aquosas. Por fim foram realizadas medidas com amostras de proteína calmodulina. Foram feitas medidas à temperatura ambiente e a 77K. Notou-se que essa proteína é passível de ser estudada por meio da técnica PAC. Para confirmar a presença da proteína nas amostras e também tentar verificar um deslocamento na massa devido à presença do íon \'ANTPOT.111 Cd\' \'ANTPOT.2+\' foram realizadas medidas de espectrometria de massas no Laboratório de Espectrometria de Massas na Embrapa em Brasília. Foi possível confirmar a presença da proteína nas amostras, porém não foi possível notar a presença de \'ANTPOT.111 Cd\' devido à baixa concentração de íons utilizados com a técnica PAC. / This work is related to the implementation of a perturbed angular correlation (PAC) spectrometer at the University of São Paulo Pelletron Laboratory. The spectrometer consists of 6 cylindrical BaF$_2$ scintillator detectors, with 3 inches diameter and 6 inches length and a multiparameter CAMAC data acquisition system. Different from usual, the gamma ray energy spectra of the cascade nuclei are acquired for each detector, which allows us to have more control of the experiment. Besides, the same experiment can be revised with different approaches at any time. With the adopted electronics configuration, the energy spectra are obtained through a QDC (charge to digital converter) module, which dispenses the use of pre-amplifiers. The time spectra are acquired with a TDC (time to digital converter) module. The selection of coincidence events is performed computationally, and this procedure can be evaluated during the data acquisition. The main motivation for implementing this spectrometer is the study of the structure and interactions of biomolecules through the perturbed angular correlation technique. Test measurements were performed, parallel to the spectrometer construction, with the use of the Hyperfine Interactions Laboratory spectrometer at the Centro do Reator de Pesquisas do Instituto de Pesquisas Energéticas e Nucleares (CRPq-IPEN). The first measurements were performed with lipidic vesicles samples. In this case it was possible to observe the influence of the molecule dimension change (decrease in one order) on the rotational correlation time at room temperature, when SDS (sodium dodecyl sulfate) was added in the suspension to form micellar aggregation. The two following series of measurements were performed with SDS samples in which the concentration was varied in order to verify modifications in the geometry or mobility of the molecules as a function of that parameter. The behavior of the experimental perturbation functions varied with the samples. However, it was not possible to point out any systematics in their behavior. The molecules behavior when in presence of methanol in the samples was very different from the aqueous solutions. Also, it was not possible to obtain a clear conclusion about the critical micellar concentration for the aqueous solutions. Finally, the last measurements were performed with calmodulin protein samples, at room temperature and at 77K. In this case we concluded that this protein can be studied through the PAC technique. In order to confirm the presence of the protein in the samples and at same time to verify if any mass displacement occurred due to the presence of the $^{111}$Cd$^{2+}$, mass spectrometry measurements were performed at the Laboratório de Espectrometria de Massas -- Embrapa in Brasília. It was possible to confirm the presence of the protein in the samples, but it was not possible to observe the mass displacement due to the presence of the $^{111}$Cd, since the ions concentration used with the PAC technique is very low.
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Electron correlations in mesoscopic systems.Sloggett, Clare, Physics, Faculty of Science, UNSW January 2007 (has links)
This thesis deals with electron correlation effects within low-dimensional, mesoscopic systems. We study phenomena within two different types of system in which correlations play an important role. The first involves the spectra and spin structure of small symmetric quantum dots, or "eartificial atoms"e. The second is the "e0.7 structure"e, a well-known but mysterious anomalous conductance plateau which occurs in the conductance profile of a quantum point contact. Artificial atoms are manufactured mesoscopic devices: quantum dots which resemble real atoms in that their symmetry gives them a "eshell structure"e. We examine two-dimensional circular artificial atoms numerically, using restricted and unrestricted Hartree-Fock simulation. We go beyond the mean-field approximation by direct calculation of second-order correlation terms; a method which works well for real atoms but to our knowledge has not been used before for quantum dots. We examine the spectra and spin structure of such dots and find, contrary to previous theoretical mean-field studies, that Hund's rule is not followed. We also find, in agreement with previous numerical studies, that the shell structure is fragile with respect to a simple elliptical deformation. The 0.7 structure appears in the conductance of a quantum point contact. The conductance through a ballistic quantum point contact is quantised in units of 2e^2/h. On the lowest conductance step, an anomalous narrow conductance plateau at about G = 0.7 x 2e^2/h is known to exist, which cannot be explained in the non-interacting picture. Based on suggestive numerical results, we model conductance through the lowest channel of a quantum point contact analytically. The model is based on the screening of the electron-electron interaction outside the QPC, and our observation that the wavefunctions at the Fermi level are peaked within the QPC. We use a kinetic equation approach, with perturbative account of electron-electron backscattering, to demonstrate that these simple features lead to the existence of a 0.7-like structure in the conductance. The behaviour of this structure reproduces experimentally observed features of the 0.7 structure, including the temperature dependence and the behaviour under applied in-plane magnetic fields.
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Using Quantum Feedback to Control Nonclassical Correlations in Light and AtomsThomsen, Laura Kathrine Wehde, n/a January 2004 (has links)
This thesis considers two types of applications of quantum feedback control; feedback creation of
nonclassical states of light, and controlling nonclassical properties of an ensemble of atoms. An electro-optical feedback loop will create an in-loop field with nonclassical photon statistics similar to squeezed light, resulting in fluorescence line-narrowing of a two-level atom coupled to such light. We extend this theory to study a three-level atom coupled to broadband squashed light, and confirm the two-level atom line-narrowing using a more realistic non-Markovian description of the feedback loop. The second type of application utilizes continuous QND measurement of atomic ensembles. If we measure the collective spin, then the system experiences conditional spin squeezing dependent on the measurement results. We show that feedback based on these results can continuously drive the system into the same conditioned state, resulting in deterministically reproducible spin squeezing. If we measure the atom number fluctuations of a BEC, then, due to the nonlinearity of atomic self interactions, this is also information about phase fluctuations. We show that feedback based on this information can greatly reduce the collisional broadening of the linewidth of an atom laser out-coupled from the condensate.
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Women's labour market participation interacting with macroeconomic growth and family policiesLuci, Angela 23 October 2009 (has links) (PDF)
Cette thèse de doctorat en économie recherche le lien entre l'emploi des femmes et la croissance macroéconomique en prenant en compte les effets des politiques familiales. Tandis que plusieurs modèles théoriques et analyses empiriques montrent un impact strictement positif de l'emploi des femmes sur la croissance macroéconomique, l'impact inverse de la croissance sur l'emploi des femmes n'est pas si clair. Quelques economistes suggèrent un impact strictement positif, mais des études empiriques recentes estiment que la croissance du PIB baisse d'abord l'emploi des femmes et l'augmente seulement à mi et long terme à partir d'un certain niveau de développement économique. Cet impact convexe (" feminisation U " hypothesis) n'est pas encore prouvé par des études empiriques, car les études existantes se basent seulement sur des donnés de séries temporelles ou de séries transversales et n'apportent pas des résultats explicites. Je propose donc une propre analyse empirique de l'impact de la croissance macroéconomique sur l'emploi des femmes, basée sur des données de panel, qui contiennent des observations de plus de 180 pays et de plus de 40 ans. La structure de la base de données me permet de prendre en compte des problèmes d'endogeneité. Mon analyse confirme un impact convex de la croissance macroéconomique sur l'emploi des femmes. Ce résultat montre que pour promouvoir l'emploi des femmes, on ne peut pas toujous compter sur la croissance. Des institutions promouvant l'égalité hommes-femmes sont nécessaires pour encourager l'emploi des femmes, et surtout l'emploi des mères, non seulement dans les pays en developpement mais aussi dans les pays industrialisés. Pourtant, dans de nombreux pays européens, le caractère redistributif de plusieurs instruments de la politique familiale risque de decourager l'offre d'emploi des mères. Par conséquent, il apparait essentiel de créer un set coherent d'instruments de politique familiale pour en même temps prévenir les familles de la pauvreté et encourager l'emploi des mères et la fécondité.
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Correlations between fearfulness and social behaviours in an F7 intercross of red junglefowl and White Leghorn layersKarlsson, Johanna January 2009 (has links)
<p>The aim of this thesis was to study chickens of an F7 intercross between red junglefowl and White Leghorn layers in five behavioural tests to see if there were any correlations between traits in the intercross. 80 animals were used (40 males, 40 females); they were tested in a tonic immobility test, an open field, a fear of human test, an aggression test and lastly a sociality test. The results indicate a pair of correlations between the different variables; chickens with long tonic immobility duration were less aggressive, and chickens with a high fear of humans were more social towards other chickens, which could suggest a correlation between fear and social behaviour/aggression. The results from this study also support previous studies showing that one QTL controls chickens’ behaviour in the tonic immobility test based on the correlations found between the variables in the tonic immobility test. Differences between the genders were found in variables that correlated with each other; this could lead to a speculative suggestion that those behaviours are affected by genes on the X-chromosome. There was also a significant relationship between the weight of the male chickens and their behaviour in the open field test and in the fear of human test, in which the heavier males were less fearful than the lighter ones.</p>
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Eye preference in human subjects : Consistency across measures and correlation with handednessBengtsson, Therése January 2010 (has links)
<p>The aim of the present study was to determine the distributions of and correlations between hand preference, visual acuity and eye preference through a series of tests in 50 males 50 females aged between 17 and 39 years. Handedness was determined through the Edinburgh handedness inventory questionnaire. The handedness distribution was: right-handed 90%, left-handed 1 %, and ambidextrous 9%. I found that 30 % had better visual acuity with their right eye, 39 % had better visual acuity with their left eye, and 31% had the same visual acuity with both eyes. 75.2% on average used their right eye in the battery of tests and 24.8% on average used their left eye. There were no statistically significant differences between the sexes or age groups with any of the measures. No correlation was found between eye preference and visual acuity or eye preference and hand preference among all subjects. No statistically significance between the sexes was found.</p>
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