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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.
51

Avaliação Cefalométrica Comparativa da Interceptação da Má Oclusão de Classe II, 1ª Divisão, Utilizando o Aparelho de Frankel e Bionator de Balters.

Almeida, Marcio Rodrigues de 15 March 2000 (has links)
Nesta investigação, objetivou-se avaliar as alterações cefalométricas em jovens com má oclusão de Classe II, 1a divisão tratados com os aparelhos de Fränkel e Bionator de Balters e comparar a um grupo de jovens portadores da mesma má oclusão que não receberam tratamento. Para tanto, utilizou-se 132 telerradiografias em norma lateral de 66 jovens, divididos em três grupos de 22, sendo 11 do sexo masculino e 11 do feminino. Os jovens do grupo 1 foram mantidos como controle e apresentaram uma idade média inicial de oito anos e sete meses. O grupo 2, foi submetido ao tratamento utilizando o aparelho de Fränkel, com idade média inicial de nove anos. O grupo 3, recebeu tratamento por meio do Bionator de Balters, com idade média inicial de dez anos e oito meses. Para cada jovem corresponderam duas telerradiografias, obtidas ao início e no final do período de acompanhamento. As variáveis cefalométricas foram mensuradas e submetidas ao tratamento estatístico. Os resultados demonstraram que os aparelhos referidos não promoveram alterações no desenvolvimento maxilar. No entanto, os aparelhos estudados produziram um aumento na protrusão mandibular e nos comprimentos efetivo e do corpo da mandíbula, com valores maiores para o grupo 3. A relação maxilomandibular melhorou significantemente nos grupos tratados em comparação ao grupo controle. A análise do padrão de crescimento craniofacial não revelou alteração significante entre os grupos. A altura facial ântero-inferior não denotou alteração significante, porém no grupo 3, a altura facial posterior aumentou significantemente. As alterações dentoalveolares demonstraram que os incisivos superiores e inferiores inclinaram-se, respectivamente, para lingual e para vestibular nos grupos tratados. Os molares inferiores apresentaram um maior desenvolvimento vertical nos grupos 2 e 3. Os aparelhos de Fränkel e Bionator promoveram uma retrusão do lábio superior e uma protrusão do lábio inferior. / The purpose of this investigation was to evaluate and compare the cephalometric changes of Fränkel and Bionator appliances on individuals with Class II, division 1 malocclusion. Lateral cephalograms were available for 66 patients of both sex, divided in three groups of 22 each one. The first group served as a control group, with initial mean age of 08 years and 07 months. The second group was treated with Fränkel appliance with initial mean age of 9 years. The group 3 was treated with Bionator appliance with initial mean age of 10 years and 08 months. The lateral cephalometric headfilms was taken of each patient at the beginning and the end of treatment, in a total of 132 headfilms. The cephalometric variables were analysed with statistical tests. The results showed that there are no changes in forward growth of the maxilla in the experimental groups (2 and 3). However, it was observed that both appliances provides a statistically significant increase in mandibular protrusion, in total mandibular and body lenght, with greatear values in group 3. This study indicated that both appliances provides an improvement in the maxillomandibular relationship, compared to the control group. In addition, there were no statistically significant differences in the craniofacial growth pattern between the three groups. The group treated with the Bionator demonstrated a greater increase in posterior facial height. It was observed that both appliances produced labial tipping and protrusion of the lower incisors and a lingual inclination of the upper incisors. The lower molars showed a greater vertical development in second and third groups. This investigation indicated that both treated groups produced a retrusion in the upper lips and a lower lip protrusion.
52

Mimicking Photosystem II With Synthetic Manganese Complexes

Lo, Wen-Feng January 2008 (has links)
Thesis advisor: William H. Armstrong / The Oxygen-Evolving Complex (OEC) of Photosystem II (PSII) utilizes a Mn4Ca cluster to catalyze the conversion of water to dioxygen within plant chloroplasts. The active site of the water oxidase is found on the lumenal side of the thylakoid membrane. For many years, the nature of this convoluted system, including the unresolved structural arrangement of the OEC manganese-oxo aggregate, stimulated on-going research projects in a diverse set of scientific fields. A tetranuclear oxo-bridged manganese complex associated with calcium [Ca] and chloride [Cl], along with a redox active tyrosine (Tyr), is thought to be the center of this remarkable and unique biological machinery. An illustrious catalytic cycle, known as the Kok cycle, progresses through a series of five intermediate states (Si, i = 0-4) to conduct water oxidation and dioxygen evolution. A tentative structural proposal based on the single crystal X-ray diffraction (XRD) crystallographic measurements introduced a CaMn3 cubane cluster and an appended fourth manganese atom. It was proposed that water binds between the “dangling” Mn atom and the Ca atom, and that is where the O-O bond formation is proposed to occur, followed by O2 release without structural rearrangement of the cubane core. The plausible manganyl (MnV=O) species was also suggested as an intermediate in the S4 state for the O-O bond formation and release O2. We have examined plausible reactive manganyl species as are proposed to exist at the OEC S4 state. The existence of manganyl in synthetic model systems will be presented in Chapter 2. In this study, we utilized stopped-flow UV-vis spectroscopy and mass spectrometry to investigate the formation and the nature of the intermediate in the reaction between mononuclear Schiff base manganese complexes and a reagent that is often used for O atom transfer reactions. Chapter 3 involves establishment of a logical synthetic method to prepare the related complexes, Mn2O2(bpy/dmb)2(ArRCOO)2 [R = 2,6-diphenyl, 2,6-ditolyl]. The dimanganese-oxo center is considered as a basic unit on the path toward the construction of higher nuclearity of Mn aggregates, preferably Mn4 clusters to be used for OEC catalytic cycle mimicry. Controlled ligand exchange synthesis of this type of carboxylate-rich/bridged {Mn2O2} dimers will provide an alternate pathway toward obtaining the Mn aggregates that are not attainable by direct ‘self-assembly’ synthetic methods. In Chapter 4, we will describe a novel mixed-ligand tetranuclear Mn cluster of the adamantane core type, [Mn4(μ-O6)(bpy)4(py)4](ClO4)4. This cluster was synthesized by using a simple reaction and its spectroscopic characterization will be discussed. We will also demonstrate chromatographic behavior of the Mn clusters that we encountered in this work (see Appendix A). / Thesis (PhD) — Boston College, 2008. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.
53

Avaliação Cefalométrica Comparativa da Interceptação da Má Oclusão de Classe II, 1ª Divisão, Utilizando o Aparelho de Frankel e Bionator de Balters.

Marcio Rodrigues de Almeida 15 March 2000 (has links)
Nesta investigação, objetivou-se avaliar as alterações cefalométricas em jovens com má oclusão de Classe II, 1a divisão tratados com os aparelhos de Fränkel e Bionator de Balters e comparar a um grupo de jovens portadores da mesma má oclusão que não receberam tratamento. Para tanto, utilizou-se 132 telerradiografias em norma lateral de 66 jovens, divididos em três grupos de 22, sendo 11 do sexo masculino e 11 do feminino. Os jovens do grupo 1 foram mantidos como controle e apresentaram uma idade média inicial de oito anos e sete meses. O grupo 2, foi submetido ao tratamento utilizando o aparelho de Fränkel, com idade média inicial de nove anos. O grupo 3, recebeu tratamento por meio do Bionator de Balters, com idade média inicial de dez anos e oito meses. Para cada jovem corresponderam duas telerradiografias, obtidas ao início e no final do período de acompanhamento. As variáveis cefalométricas foram mensuradas e submetidas ao tratamento estatístico. Os resultados demonstraram que os aparelhos referidos não promoveram alterações no desenvolvimento maxilar. No entanto, os aparelhos estudados produziram um aumento na protrusão mandibular e nos comprimentos efetivo e do corpo da mandíbula, com valores maiores para o grupo 3. A relação maxilomandibular melhorou significantemente nos grupos tratados em comparação ao grupo controle. A análise do padrão de crescimento craniofacial não revelou alteração significante entre os grupos. A altura facial ântero-inferior não denotou alteração significante, porém no grupo 3, a altura facial posterior aumentou significantemente. As alterações dentoalveolares demonstraram que os incisivos superiores e inferiores inclinaram-se, respectivamente, para lingual e para vestibular nos grupos tratados. Os molares inferiores apresentaram um maior desenvolvimento vertical nos grupos 2 e 3. Os aparelhos de Fränkel e Bionator promoveram uma retrusão do lábio superior e uma protrusão do lábio inferior. / The purpose of this investigation was to evaluate and compare the cephalometric changes of Fränkel and Bionator appliances on individuals with Class II, division 1 malocclusion. Lateral cephalograms were available for 66 patients of both sex, divided in three groups of 22 each one. The first group served as a control group, with initial mean age of 08 years and 07 months. The second group was treated with Fränkel appliance with initial mean age of 9 years. The group 3 was treated with Bionator appliance with initial mean age of 10 years and 08 months. The lateral cephalometric headfilms was taken of each patient at the beginning and the end of treatment, in a total of 132 headfilms. The cephalometric variables were analysed with statistical tests. The results showed that there are no changes in forward growth of the maxilla in the experimental groups (2 and 3). However, it was observed that both appliances provides a statistically significant increase in mandibular protrusion, in total mandibular and body lenght, with greatear values in group 3. This study indicated that both appliances provides an improvement in the maxillomandibular relationship, compared to the control group. In addition, there were no statistically significant differences in the craniofacial growth pattern between the three groups. The group treated with the Bionator demonstrated a greater increase in posterior facial height. It was observed that both appliances produced labial tipping and protrusion of the lower incisors and a lingual inclination of the upper incisors. The lower molars showed a greater vertical development in second and third groups. This investigation indicated that both treated groups produced a retrusion in the upper lips and a lower lip protrusion.
54

The dramatic function of deception in Woodstock

Soper, David January 2010 (has links)
Digitized by Kansas Correctional Industries
55

Nuclear magnetic resonance and nuclear quadrupole resonance study of atomic motion in YBa���Cu���O���

Klein, Susan P. 25 October 1995 (has links)
Graduation date: 1996
56

Physical conditions in giant extragalactic H II regions /

Skillman, Evan David. January 1984 (has links)
Thesis (Ph. D.)--University of Washington, 1984. / Vita. Bibliography: leaves 201-207.
57

Transport of lysosome-related organelles /

Jordens, Ingrid. January 2005 (has links)
University, Diss.--Leiden, 2005. / Zsfassung in niederl. Sprache.
58

Assembly and function of myosin II on ultraviolet/ozone patterned trimethylchlorosilane substrates.

Kolli, Madhukar B. January 2008 (has links)
Thesis (M.S.) --Marshall University, 2008. / Title from document title page. Includes abstract. Document formatted into pages: contains 51 pages. Includes bibliographical references (p. 37-38).
59

Assembly and function of myosin II on ultraviolet/ozone patterned trimethylchlorosilane substrates.

Kolli, Madhukar B. January 2008 (has links)
Thesis (M.S.) --Marshall University, 2008. / Title from document title page. Includes abstract. Document formatted into pages: contains 51 pages. Includes bibliographical references (p. 37-38).
60

The role of secretin in mediating the osmoregulatory functions of angiotensin II

Lee, Hoi-yi, Vien, January 2009 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2010. / Includes bibliographical references (leaves 164-201). Also available in print.

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