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Music as a tool to strengthen reading skillsLenertz, Michele Lynn 01 January 2002 (has links)
This project focused on the rate of growth in reading skills of two first grade classrooms. The goal of this project was to improve the reading skills of below grade level students through musical activities.
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Magnetic Resonance Parameters of Radicals Studied by Density Functional Theory MethodsTelyatnyk, Lyudmyla January 2004 (has links)
<p>The recent state of art in the magnetic resonance area putsforward the electron paramagnetic resonance, EPR, and nuclearmagnetic resonance, NMR, experiments on prominent positions forinvestigations of molecular and electronic structure. A mostdifficult aspect of such experiments is usually the properinterpretation of data obtained from high-resolution spectra,that, however, at the same time opens a great challenge forpure theoretical methods to interpret the spectral features.This thesis constitutes an effort in this respect, as itpresents and discusses calculations of EPR and NMR parametersof paramagnetic molecules. The calculations are based on newmethodology for determination of properties of paramagneticmolecules in the framework of the density functional theory,which has been developed in our laboratory.</p><p>Paramagnetic molecules are, in some sense, very special. Thepresence of unpaired electrons essentially modifies theirspectra. The experimental determination of the magneticresonance parameters of such molecules is, especially in theNMR case, quite complicated and requires special techniques ofspectral detection. The significant efforts put into suchexperiments are completely justi fied though by the importantroles of paramagnetic species playing in many areas, such as,for example, molecular magnets, active centers in biologicalsystems, and defects in inorganic conductive materials.</p><p>The first two papers of this thesis deal with thetheoretical determination of NMR parameters, such as thenuclear shielding tensors and the chemical shifts, inparamagnetic nitroxides that form core units in molecularmagnets. The developed methodology aimed to realize highaccuracy in the calculations in order to achieve successfulapplications for the mentioned systems. Theeffects of hydrogenbonding are also described in that context. Our theory forevaluation of nuclear shielding tensors in paramagneticmolecules is consistent up to the second order in the finestructure constant and considers orbital, fully isotropicdipolar, and isotropic contact contributions to the shieldingtensor.</p><p>The next three projects concern electron paramagneticresonance. The wellknown EPR parameters, such as the g-tensorsand the hyperfine coupling constants are explored. Calculationsof electronic g-tensors were carried out in the framework of aspin-restricted open-shell Kohn-Sham method combined with thelinear response theory recently developed in our laboratory.The spincontamination problem is then automatically avoided.The solvent effects, described by the polarizable continuummodel, are also considered. For calculations of the hyperfinecoupling constants a so-called restricted-unrestricted approachhas been developed in the context of density functional theory.Comparison of experimentally and theoretically determinedparameters shows that qualitative mutual agreement of the twosets of data can be easily achieved by employing the proposedformalisms.</p>
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Magnetic Resonance Parameters of Radicals Studied by Density Functional Theory MethodsTelyatnyk, Lyudmyla January 2004 (has links)
The recent state of art in the magnetic resonance area putsforward the electron paramagnetic resonance, EPR, and nuclearmagnetic resonance, NMR, experiments on prominent positions forinvestigations of molecular and electronic structure. A mostdifficult aspect of such experiments is usually the properinterpretation of data obtained from high-resolution spectra,that, however, at the same time opens a great challenge forpure theoretical methods to interpret the spectral features.This thesis constitutes an effort in this respect, as itpresents and discusses calculations of EPR and NMR parametersof paramagnetic molecules. The calculations are based on newmethodology for determination of properties of paramagneticmolecules in the framework of the density functional theory,which has been developed in our laboratory. Paramagnetic molecules are, in some sense, very special. Thepresence of unpaired electrons essentially modifies theirspectra. The experimental determination of the magneticresonance parameters of such molecules is, especially in theNMR case, quite complicated and requires special techniques ofspectral detection. The significant efforts put into suchexperiments are completely justi fied though by the importantroles of paramagnetic species playing in many areas, such as,for example, molecular magnets, active centers in biologicalsystems, and defects in inorganic conductive materials. The first two papers of this thesis deal with thetheoretical determination of NMR parameters, such as thenuclear shielding tensors and the chemical shifts, inparamagnetic nitroxides that form core units in molecularmagnets. The developed methodology aimed to realize highaccuracy in the calculations in order to achieve successfulapplications for the mentioned systems. Theeffects of hydrogenbonding are also described in that context. Our theory forevaluation of nuclear shielding tensors in paramagneticmolecules is consistent up to the second order in the finestructure constant and considers orbital, fully isotropicdipolar, and isotropic contact contributions to the shieldingtensor. The next three projects concern electron paramagneticresonance. The wellknown EPR parameters, such as the g-tensorsand the hyperfine coupling constants are explored. Calculationsof electronic g-tensors were carried out in the framework of aspin-restricted open-shell Kohn-Sham method combined with thelinear response theory recently developed in our laboratory.The spincontamination problem is then automatically avoided.The solvent effects, described by the polarizable continuummodel, are also considered. For calculations of the hyperfinecoupling constants a so-called restricted-unrestricted approachhas been developed in the context of density functional theory.Comparison of experimentally and theoretically determinedparameters shows that qualitative mutual agreement of the twosets of data can be easily achieved by employing the proposedformalisms.
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Multi-detector registration system for the study of multi-body decay of heavy body nucleiMalaza, Vusi David 12 1900 (has links)
Thesis (MMil)--Stellenbosch University, 2012. / Includes bibliography / Nuclear ssion is commonly known as a process where a heavy nucleus such as Uranium
or Thorium decays into two fragments of roughly equal mass. On occasion however, instead
of decay into two parts a process known as binary ssion, the nucleus can decay
into three fragments. In this decay channel known as ternary ssion, the nucleus splits
into three fragments with the third particle being too light compared to the main ssion
fragments. There are also instances where heavy nuclei split into three fragments of comparable
masses, the so called \true ternary ssion" as was predicted by the theoretical
calculations of Strutinsky [Str63]. While theoretical predictions hold promises for this decay
mode, experimental attempts had little success in proving the existence of true ternary
ssion in low energy ssion. The challenges and di culties faced by experimentalist in
con rming the existence of true ternary ssion also proved that this ssion mode is a very
rare phenomenon.
This thesis is devoted to the investigation of ternary ssion know as collinear cluster tripartition
(CCT) in spontaneous ssion of 252Cf, and the design and development of two
time-of-
ight spectrometers aimed at identifying all collinear multi-body decay partners
directly. Prior to this study the only technique that was used at identifying decay partners
in CCT was the \missing mass" approach. In this approach only two partners are identi ed
directly with the third partner being identi ed by subtracting the two observed partners
from the initial mass of the nucleus.
The experimental results from the two spectrometer setups showed that it was possible
to identify all three partners of the CCT channel. The results also con rmed the existence
of the so called \Sn lost" CCT mode which was already observed in earlier experiments. / National Research Foundation (NRF) / Joint Institute of Nuclear Science (JINR) / Financial support from Dr D V Kamanim / Dept of Science and Technology (DST)
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Modelagem do processo de fermentação etanólica com interferência de bactérias heterofermentativa e homofermentativa / Interference modelling of heterofermentative and homofermentative bacteria in the ethanol fermentation processYabarrena, Jean Mimar Santa Cruz 04 May 2012 (has links)
O processo fermentativo para a obtenção de etanol constitui um sistema complexo. Durante a fermentação se desenvolvem infecções em forma crônica e os surtos de infecção aguda aparecem em condições que; por causa da dinâmica não-linear do processo que envolve uma rede de reações metabólicas dos microrganismos, a alta dependência às condições de contorno e pelas interações sinérgicas e antagônicas envolvidas neste ecossistema; ainda representam um tema relevante de pesquisa em aberto. O presente trabalho propõe contribuir na tarefa de interpretar tais efeitos por intermédio de um modelo que inclua a interferência das bactérias. É proposto um cenário em escala laboratorial e controlado com a linhagem isolada de Saccharomyces cerevisiae PE-2 em co-cultura com bactérias de metabolismo heterofermentativo e homofermentativo. A interferência é explicada por intermédio de um modelo com efeito fixo baseado em um modelo não estruturado proposto por Lee (1983), e modificado a partir dos estudos de Andrietta (2003). São conduzidos ensaios de quatro tratamentos: uma fermentação controle e outras contaminadas com cada um dos diferentes tipos de bactérias e também em conjunto, a fim de fornecer dados experimentais para ajuste do modelo em discussão. Em seguida, são realizadas estimativas dos parâmetros que compõem as equações diferenciais da cinética da fermentação, utilizando um algoritmo genético baseado em evolução diferencial Storn e Price (1997). Completa-se a avaliação dos parâmetros por intermédio da análise de sensibilidade paramétrica dos mesmos. De posse desses resultados, é utilizado o modelo do tratamento controle como base, e são inseridos vetores de variáveis categóricas, correspondentes a efeitos fixos. Tais variáveis permitem modelar a interferência da contaminação no modelo matemático proposto. A estatística descritiva, a análise utilizando inferência bayesiana e a interpretação bioquímica dos resultados complementam as inferências obtidas a respeito do modelo. A análise de sensibilidade e correlação dos parâmetros, mostrou que os modelos para a cinética da fermentação, estudados e bem conhecidos não são adequados para modelar o processo, pela alta correlação dos seus parâmetros. O tratamento controle teve um rendimento de 46,97% na produção de etanol, o tratamento com bactéria heterofermentativa teve uma redução de 2.35% e com a mistura de ambas a redução foi de 1,58%. Uma das principais contribuições deste estudo relacionasse à produção de glicerol, o resultado mostra que no há impacto significativo na presença de bactérias homofermentativas e sim uma clara tendência a inibir a sua produção. Apresentam-se também indícios de sinergia entre as bactérias e de consumo de manitol pela bactéria homofermentativa. / The fermentation process for obtaining ethanol is a complex system. During fermentation develop chronic infections and outbreaks of acute infection in conditions that appear, because of the nonlinear dynamics of the process that involves a network of metabolic reactions of microorganisms, the high dependence on boundary conditions and the synergistic interactions and antagonistic involved in this ecosystem, still represent a relevant topic of research open. This paper proposes to contribute in the interpreting such effects through a model that includes the interference of bacteria. We propose a scenario in laboratory scale and controlled with the strain isolated from Saccharomyces cerevisiae PE-2 in co-culture with bacteria and homofermentativo heterofermentative metabolism. The interference is explained by means of a template with fixed effect based on a non structured proposed by Lee (1983) and modified from studies Andrietta (2003). Tests are conducted four treatments: a control fermentation and other contaminated with each of the different bacteria and also in conjunction in order to provide experimental data to fit the model under discussion. Are then carried estimates of the parameters that make up the differential equations of the kinetics of the fermentation, using a genetic algorithm based on differential evolution Storm and Price (1997). To complete the parameters evaluated through analysis of the same parameter sensitivity. With these results, the model is used as the basis of the control treatment, and are inserted vectors of categorical variables, corresponding to fixed effects. These variables allow modeling the interference of contamination in the mathematical model. Descriptive statistics and Bayesian inference analysis and interpretation of biochemical results obtained complement inferences about the model. Sensitivity analysis and correlation of parameters for the models showed that the kinetics of the fermentation, well studied and known are not suitable for modeling the process, the high correlation between the parameters. The control had a yield of 46.97% in ethanol, treatment with heterofermentative bacteria was reduced by 2.35% and a mixture of both reduction was 1.58%. A major contribution of this study is related to the glycerol, the result shows that no significant impact on the presence of homofermentative bacteria but a clear tendency to inhibit their production. It also presents evidence of synergy between bacteria and consumption of mannitol by homofermentative bacteria.
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Modelagem do processo de fermentação etanólica com interferência de bactérias heterofermentativa e homofermentativa / Interference modelling of heterofermentative and homofermentative bacteria in the ethanol fermentation processJean Mimar Santa Cruz Yabarrena 04 May 2012 (has links)
O processo fermentativo para a obtenção de etanol constitui um sistema complexo. Durante a fermentação se desenvolvem infecções em forma crônica e os surtos de infecção aguda aparecem em condições que; por causa da dinâmica não-linear do processo que envolve uma rede de reações metabólicas dos microrganismos, a alta dependência às condições de contorno e pelas interações sinérgicas e antagônicas envolvidas neste ecossistema; ainda representam um tema relevante de pesquisa em aberto. O presente trabalho propõe contribuir na tarefa de interpretar tais efeitos por intermédio de um modelo que inclua a interferência das bactérias. É proposto um cenário em escala laboratorial e controlado com a linhagem isolada de Saccharomyces cerevisiae PE-2 em co-cultura com bactérias de metabolismo heterofermentativo e homofermentativo. A interferência é explicada por intermédio de um modelo com efeito fixo baseado em um modelo não estruturado proposto por Lee (1983), e modificado a partir dos estudos de Andrietta (2003). São conduzidos ensaios de quatro tratamentos: uma fermentação controle e outras contaminadas com cada um dos diferentes tipos de bactérias e também em conjunto, a fim de fornecer dados experimentais para ajuste do modelo em discussão. Em seguida, são realizadas estimativas dos parâmetros que compõem as equações diferenciais da cinética da fermentação, utilizando um algoritmo genético baseado em evolução diferencial Storn e Price (1997). Completa-se a avaliação dos parâmetros por intermédio da análise de sensibilidade paramétrica dos mesmos. De posse desses resultados, é utilizado o modelo do tratamento controle como base, e são inseridos vetores de variáveis categóricas, correspondentes a efeitos fixos. Tais variáveis permitem modelar a interferência da contaminação no modelo matemático proposto. A estatística descritiva, a análise utilizando inferência bayesiana e a interpretação bioquímica dos resultados complementam as inferências obtidas a respeito do modelo. A análise de sensibilidade e correlação dos parâmetros, mostrou que os modelos para a cinética da fermentação, estudados e bem conhecidos não são adequados para modelar o processo, pela alta correlação dos seus parâmetros. O tratamento controle teve um rendimento de 46,97% na produção de etanol, o tratamento com bactéria heterofermentativa teve uma redução de 2.35% e com a mistura de ambas a redução foi de 1,58%. Uma das principais contribuições deste estudo relacionasse à produção de glicerol, o resultado mostra que no há impacto significativo na presença de bactérias homofermentativas e sim uma clara tendência a inibir a sua produção. Apresentam-se também indícios de sinergia entre as bactérias e de consumo de manitol pela bactéria homofermentativa. / The fermentation process for obtaining ethanol is a complex system. During fermentation develop chronic infections and outbreaks of acute infection in conditions that appear, because of the nonlinear dynamics of the process that involves a network of metabolic reactions of microorganisms, the high dependence on boundary conditions and the synergistic interactions and antagonistic involved in this ecosystem, still represent a relevant topic of research open. This paper proposes to contribute in the interpreting such effects through a model that includes the interference of bacteria. We propose a scenario in laboratory scale and controlled with the strain isolated from Saccharomyces cerevisiae PE-2 in co-culture with bacteria and homofermentativo heterofermentative metabolism. The interference is explained by means of a template with fixed effect based on a non structured proposed by Lee (1983) and modified from studies Andrietta (2003). Tests are conducted four treatments: a control fermentation and other contaminated with each of the different bacteria and also in conjunction in order to provide experimental data to fit the model under discussion. Are then carried estimates of the parameters that make up the differential equations of the kinetics of the fermentation, using a genetic algorithm based on differential evolution Storm and Price (1997). To complete the parameters evaluated through analysis of the same parameter sensitivity. With these results, the model is used as the basis of the control treatment, and are inserted vectors of categorical variables, corresponding to fixed effects. These variables allow modeling the interference of contamination in the mathematical model. Descriptive statistics and Bayesian inference analysis and interpretation of biochemical results obtained complement inferences about the model. Sensitivity analysis and correlation of parameters for the models showed that the kinetics of the fermentation, well studied and known are not suitable for modeling the process, the high correlation between the parameters. The control had a yield of 46.97% in ethanol, treatment with heterofermentative bacteria was reduced by 2.35% and a mixture of both reduction was 1.58%. A major contribution of this study is related to the glycerol, the result shows that no significant impact on the presence of homofermentative bacteria but a clear tendency to inhibit their production. It also presents evidence of synergy between bacteria and consumption of mannitol by homofermentative bacteria.
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