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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.
1

Observation of a BEH-like boson decaying into two photons with the ATLAS detector at the LHC / Observation d'un boson de type BEH se désintégrant en deux photons dans le détecteur ATLAS au LHC

Andari, Nansi 26 September 2012 (has links)
Dans cette thèse, je présente ma contribution à l'observation d'un nouveau boson au LHC avec le détecteur ATLAS dans le canal de désintégration en deux photons. Ce boson est compatible avec le boson scalaire du Modèle Standard longtemps recherché et a une masse de 126.0 +/-0.4 (stat) +/-0.4 (sys) GeV obtenue en combinant les canaux gamma gamma et ZZ. Les données utilisées sont celles collectées par l'expérience ATLAS durant l'année 2011 avec une énergie de centre de masse de 7 TeV et durant les trois premiers mois du run en 2012 avec une énergie de centre de masse de 8 TeV. La luminosité totale correspondante est de ~10 fb-1. L'excès observé a une significance locale de 4.5 sigma dans le canal gamma gamma et de 5.9 sigma en combinant tous les canaux analysés. De même, diverses contributions aux analyses des données, dans le canal H en gamma gamma, depuis l'année 2009 jusqu'en 2012 sont aussi montrées. / In this thesis, I show my contribution to the observation of a new boson at the Large Hadron Collider with the ATLAS detector in the diphoton decay channel. This boson is compatible with the long-searched scalar boson of the Standard Model and has a mass of 126.0+/-0.4+/- 0.4 (sys) GeV obtained when combining the decay channels gamma gamma and ZZ. The data used were collected in the ATLAS experiment during 2011 with a center-of-mass energy of 7 TeV and during the first three months of the 2012 run with a center-of-mass energy of 8 TeV. The total corresponding luminosity is about 10 fb-1. The observed excess has a local significance of 4.5 sigma in the gamma gamma channel and has a significance of 5.9 sigma when combining all the channels used in the analysis. Moreover, diverse contributions to the H into gamma gamma analyses of the data from 2009 to 2012 are also shown.
2

Observation d'un boson de type BEH se désintégrant en deux photons dans le détecteur ATLAS au LHC

Andari, Nansi 26 September 2012 (has links) (PDF)
Dans cette thèse, je présente ma contribution à l'observation d'un nouveau boson au LHC avec le détecteur ATLAS dans le canal de désintégration en deux photons. Ce boson est compatible avec le boson scalaire du Modèle Standard longtemps recherché et a une masse de 126.0 +/-0.4 (stat) +/-0.4 (sys) GeV obtenue en combinant les canaux gamma gamma et ZZ. Les données utilisées sont celles collectées par l'expérience ATLAS durant l'année 2011 avec une énergie de centre de masse de 7 TeV et durant les trois premiers mois du run en 2012 avec une énergie de centre de masse de 8 TeV. La luminosité totale correspondante est de ~10 fb-1. L'excès observé a une significance locale de 4.5 sigma dans le canal gamma gamma et de 5.9 sigma en combinant tous les canaux analysés. De même, diverses contributions aux analyses des données, dans le canal H en gamma gamma, depuis l'année 2009 jusqu'en 2012 sont aussi montrées.
3

Caracterização histopatológica e imunoistoquímica de bexigas de bovinos com hematúra enzoótica

Silva, Maria Aparecida da 27 February 2012 (has links)
Made available in DSpace on 2016-12-23T13:53:40Z (GMT). No. of bitstreams: 1 Maria Aparecida da Silva.pdf: 3366725 bytes, checksum: 59d418ef608b4e75da9a6ba6a1fdb233 (MD5) Previous issue date: 2012-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Bovine enzootic hematuria (BEH) is caused by chronic ingestion of Pteridium aquilinum and is characterized by the presence of blood in the urine and development of lesions in the urinary bladder and is responsible for economic losses. Poisoning by this plant can also occur in humans. The objective was to evaluate the lesions in bladders of animals with BEH in the south region of the Espírito Santo. For this, were evaluated 350 bladders of bovines in a slaughterhouse and, of these, selected 46 that had macroscopic lesions and/or hematuria. Samples of each bladder were fixed in formalin 10% submitted to histological processing and classified by histomorphology. The immunohistochemistry was performed with anti-vimentin, anti-cytokeratin, anti-CD31, anti-VEGF and anti-uroplakin only in the 26 bladders that presented neoplastic lesions. Non-neoplastic lesions were observed in 100% of samples and the neoplastic in 56.52%. The presence of tumors was significant (p<0.05) in the caudal portion of the bladder. Detected neoplastic types were urothelial carcinoma, in situ carcinoma, adenocarcinoma, hemangioma, myxoma and hemangiosarcoma. There was a higher frequency of dysplasia, clear cell metaplasia, inflammation and vascular thickening in bladders with neoplasm. The expression of cytokeratin was significant (p<0.05) in epithelial neoplasms and vimentin in mesenchymal neoplasms. Uroplakin III differed in varied types of neoplastic lesions and showed to be typical and atypical while that of CD31 was significantly (p <0.05) in vascular mesenchymal neoplasms. A significant difference (p <0.05) in the number of vessels extratumorais stained by VEGF between myxomas and adenocarcinomas, and in intratumoral vessels stained by CD31 and VEGF in the different tumor types. Positive correlation existed between the number of intra- and extratumoral vessels in hemangiomas, hemangiosarcomas, and myxomas stained by CD31; between hemangiomas, myxomas, and adenocarcinomas stained with VEGF; between the expression of vimentin and CD31 and between cytokeratin and uroplakin. It is concluded that bladders from bovines with BEH have non-neoplastic and neoplastic lesions, isolated or associated. Biomarkers aid in the differentiation of the histogenesis of epithelial and vascular mesenchymal neoplasms. Uroplakin demonstrated to be effective for the assessment of integrity urothelial, and vascular markers (CD31 and VEGF) for endothelial integrity and for prognosis / A hematúria enzoótica bovina (HEB) é causada pela ingestão crônica de Pteridium aquilinum e caracteriza-se pela presença de sangue na urina e desenvolvimento de lesões na bexiga, sendo responsável por grandes perdas econômicas. A intoxicação por esta planta também pode ocorrer em humanos. Objetivou-se avaliar lesões de bexigas de animais com HEB na região sul do Espírito Santo. Para isto, foram avaliadas 350 bexigas de bovinos em matadouro frigorífico e, destas, selecionadas 46 que apresentavam lesões macroscópicas e/ou hematúria. Amostras de cada bexiga foram fixadas em formol a 10% submetidas ao processamento histológico de rotina e classificadas histomorfologicamente. A imunoistoquímica foi realizada com anti-vimentina, anti-citoqueratina, anti-CD31, anti-VEGF e anti-uroplaquina apenas nas 26 bexigas que revelaram neoplasia. Lesões não neoplásicas foram observadas em 100% das amostras e neoplásicas em 56,52%. A presença de neoplasias foi significativa (p<0,05) na porção caudal da bexiga. As neoplasias encontradas foram carcinoma urotelial; carcinoma in situ, adenocarcinoma, hemangioma, mixoma e hemangiossarcoma. Houve maior frequência de displasia, metaplasia de células claras, inflamação e espessamento vascular em bexigas com neoplasia. A expressão de citoqueratina foi significativa (p<0,05) nas neoplasias epiteliais e vimentina nas mesenquimais. A marcação da uroplaquina III diferiu nos diversos tipos neoplásicos e revelou-se típica e atípica enquanto que a do CD31 foi significativa (p<0,05) nas neoplasias mesenquimais vasculares. Houve diferença significativa (p<0,05) na quantidade de vasos extratumorais marcados pelo VEGF entre os mixomas e adenocarcinomas e nos vasos intratumorais marcados por CD31 e VEGF nos diferentes tipos tumorais. Houve correlação positiva entre os vasos extra e intratumorais nos hemangiomas, hemangiossarcomas e mixomas marcados pelo CD31; nos hemangiomas, mixomas e adenocarcinomas marcados pelo VEGF; entre a expressão de vimentina e CD31 e entre citoqueratina e uroplaquina. Conclui-se que bexigas de bovinos com HEB apresentam lesões não neoplásicas e neoplásicas, isoladas ou associadas. Os biomarcadores auxiliam na diferenciação da histogênese das neoplasias epiteliais e mesenquimais vasculares. Uroplaquina demonstrou-se efetiva para a avaliação da integridade urotelial e os marcadores vasculares (CD31 e VEGF) para a integridade endotelial e para o prognóstico
4

High-resolution infrared emission spectroscopy of diatomic and triatomic metal hydrides

Shayesteh, Alireza January 2006 (has links)
Several hydrides of Group 2 and 12 elements were generated in the gas phase using an emission source that combines an electrical discharge with a high temperature furnace, and their high-resolution infrared emission spectra were recorded with a Fourier transform spectrometer. Two classes of molecules were studied: <em>a)</em> diatomic metal hydrides BeH, MgH, CaH, SrH, ZnH and CdH; <em>b)</em> linear triatomic metal hydrides BeH<sub>2</sub>, MgH<sub>2</sub>, ZnH<sub>2</sub> and HgH<sub>2</sub>. <br /><br /> Infrared emission spectra of BeH, MgH, CaH, SrH, ZnH and CdH free radicals contained several vibration-rotation bands in their <sup>2</sup>SIGMA<sup>+</sup> ground electronic state. The new data were combined with all the previous ground state data from diode laser infrared spectra and pure rotation spectra available in the literature. Spectroscopic constants, i. e. , vibrational band origins, rotational, centrifugal distortion, and spin-rotation interaction constants, were determined for each observed vibrational level by least-squares fitting of all the data. In addition, the data from all isotopologues were fitted simultaneously using the empirical Dunham-type energy level expression for <sup>2</sup>SIGMA<sup>+</sup> states, and correction parameters due to the breakdown of the Born-Oppenheimer approximation were determined. The equilibrium internuclear distances (<em>r</em><sub>e</sub>) of <sup>9</sup>BeH, <sup>24</sup>MgH, <sup>40</sup>CaH, <sup>88</sup>SrH, <sup>64</sup>ZnH and <sup>114</sup>CdH were determined to be 1. 342424(2), 1. 729721(1), 2. 002360(1), 2. 146057(1), 1. 593478(2) and 1. 760098(3) angstroms, respectively, and the corresponding <em>r</em><sup>e</sup> distances for <sup>9</sup>BeD, <sup>24</sup>MgD, <sup>40</sup>CaD, <sup>88</sup>SrD, <sup>64</sup>ZnD and <sup>114</sup>CdD are 1. 341731(2), 1. 729157(1), 2. 001462(1), 2. 145073(1), 1. 593001(2) and 1. 759695(2) angstroms, respectively. <br /><br /> Gaseous BeH<sup>2</sup>, MgH<sup>2</sup>, ZnH<sup>2</sup> and HgH<sup>2</sup> molecules were discovered and unambiguously identified by their high-resolution infrared emission spectra. The &nu;<sub>3</sub> antisymmetric stretching fundamental band and several hot bands in the &nu;<sub>3</sub> region were rotationally analyzed, and spectroscopic constants were obtained for almost all naturally-occurring isotopologues. The rotational constants of the 000 ground states were used to determine the <em>r</em><sub>0</sub> internuclear distances. For BeH<sub>2</sub>, ZnH<sub>2</sub>, ZnD<sub>2</sub>, HgH<sub>2</sub> and HgD<sub>2</sub> molecules, the rotational constants of the 000, 100, 01<sup>1</sup>0 and 001 levels were used to determine the equilibrium rotational constants (<em>B</em><sub>e</sub>) and the associated equilibrium internuclear distances <em>r</em><sub>e</sub>. The <em>r</em><sub>e</sub> distances of ZnH<sub>2</sub> and ZnD<sub>2</sub> differed by about 0. 01%, and those of HgH<sub>2</sub> and HgD<sub>2</sub> differed by about 0. 005%. These discrepancies were larger than the statistical uncertainties by one order of magnitude, and were attributed to the breakdown of the Born-Oppenheimer approximation.
5

Fourier Transform Spectroscopy of Selected Transient Species

Li, Gang January 2003 (has links)
The procedures and results of experimental and/or theoretical studies of four transient molecules, GeO, WO, BeH, and MgH are reported in the thesis. Two of them, GeO and WO, are diatomic molecules composed of relatively heavy atoms, and the other two are diatomic molecules with hydrogen as one of their component atoms. The GeO species was generated using a high temperature furnace. The rovibrational spectrum of five isotopomers were detected in emission using a Bruker IFS 120 HR Fourier transform spectrometer. Combined-isotopomer Dunham-type molecular constants have been derived for GeO using the DSParFit computer program. Analysis shows that the Born-Oppenheimer approximation is valid, as expected, for a molecule containing heavy atoms. The WO molecule was generated using a microwave discharge cell, and the spectra of electronic transitions of various systems were detected in emission using both the Bruker IFS 120 HR Fourier transform spectrometer at Waterloo and the McMath Pierce One-Meter Fourier transform spectrometer at the National Solar Observatory in Arizona. The ground electronic state has been confirmed to be X??&#931;<sup>-</sup> based on the analysis of seven 0-0 bands. BeH and MgH are typical molecules with hydrogen as one of their component atoms, and the effects of Born-Oppenheimer breakdown were expected. Both of these molecules have rotational perturbations in their excited electronic states. A 'new' method of data processing was used, i. e. , treating the electronic data as if they were from fluorescence series. Thus the harmful influence of the perturbed upper electronic states on the ground electronic state molecular constants is eliminated. By using the DSParFit computer program, accurate sets of combined-isotopomer Dunham-type molecular constants have been derived for the ground electronic states of the two molecules, and Born-Oppenheimer breakdown correction terms have been obtained.
6

High-resolution infrared emission spectroscopy of diatomic and triatomic metal hydrides

Shayesteh, Alireza January 2006 (has links)
Several hydrides of Group 2 and 12 elements were generated in the gas phase using an emission source that combines an electrical discharge with a high temperature furnace, and their high-resolution infrared emission spectra were recorded with a Fourier transform spectrometer. Two classes of molecules were studied: <em>a)</em> diatomic metal hydrides BeH, MgH, CaH, SrH, ZnH and CdH; <em>b)</em> linear triatomic metal hydrides BeH<sub>2</sub>, MgH<sub>2</sub>, ZnH<sub>2</sub> and HgH<sub>2</sub>. <br /><br /> Infrared emission spectra of BeH, MgH, CaH, SrH, ZnH and CdH free radicals contained several vibration-rotation bands in their <sup>2</sup>SIGMA<sup>+</sup> ground electronic state. The new data were combined with all the previous ground state data from diode laser infrared spectra and pure rotation spectra available in the literature. Spectroscopic constants, i. e. , vibrational band origins, rotational, centrifugal distortion, and spin-rotation interaction constants, were determined for each observed vibrational level by least-squares fitting of all the data. In addition, the data from all isotopologues were fitted simultaneously using the empirical Dunham-type energy level expression for <sup>2</sup>SIGMA<sup>+</sup> states, and correction parameters due to the breakdown of the Born-Oppenheimer approximation were determined. The equilibrium internuclear distances (<em>r</em><sub>e</sub>) of <sup>9</sup>BeH, <sup>24</sup>MgH, <sup>40</sup>CaH, <sup>88</sup>SrH, <sup>64</sup>ZnH and <sup>114</sup>CdH were determined to be 1. 342424(2), 1. 729721(1), 2. 002360(1), 2. 146057(1), 1. 593478(2) and 1. 760098(3) angstroms, respectively, and the corresponding <em>r</em><sup>e</sup> distances for <sup>9</sup>BeD, <sup>24</sup>MgD, <sup>40</sup>CaD, <sup>88</sup>SrD, <sup>64</sup>ZnD and <sup>114</sup>CdD are 1. 341731(2), 1. 729157(1), 2. 001462(1), 2. 145073(1), 1. 593001(2) and 1. 759695(2) angstroms, respectively. <br /><br /> Gaseous BeH<sup>2</sup>, MgH<sup>2</sup>, ZnH<sup>2</sup> and HgH<sup>2</sup> molecules were discovered and unambiguously identified by their high-resolution infrared emission spectra. The &nu;<sub>3</sub> antisymmetric stretching fundamental band and several hot bands in the &nu;<sub>3</sub> region were rotationally analyzed, and spectroscopic constants were obtained for almost all naturally-occurring isotopologues. The rotational constants of the 000 ground states were used to determine the <em>r</em><sub>0</sub> internuclear distances. For BeH<sub>2</sub>, ZnH<sub>2</sub>, ZnD<sub>2</sub>, HgH<sub>2</sub> and HgD<sub>2</sub> molecules, the rotational constants of the 000, 100, 01<sup>1</sup>0 and 001 levels were used to determine the equilibrium rotational constants (<em>B</em><sub>e</sub>) and the associated equilibrium internuclear distances <em>r</em><sub>e</sub>. The <em>r</em><sub>e</sub> distances of ZnH<sub>2</sub> and ZnD<sub>2</sub> differed by about 0. 01%, and those of HgH<sub>2</sub> and HgD<sub>2</sub> differed by about 0. 005%. These discrepancies were larger than the statistical uncertainties by one order of magnitude, and were attributed to the breakdown of the Born-Oppenheimer approximation.
7

Fourier Transform Spectroscopy of Selected Transient Species

Li, Gang January 2003 (has links)
The procedures and results of experimental and/or theoretical studies of four transient molecules, GeO, WO, BeH, and MgH are reported in the thesis. Two of them, GeO and WO, are diatomic molecules composed of relatively heavy atoms, and the other two are diatomic molecules with hydrogen as one of their component atoms. The GeO species was generated using a high temperature furnace. The rovibrational spectrum of five isotopomers were detected in emission using a Bruker IFS 120 HR Fourier transform spectrometer. Combined-isotopomer Dunham-type molecular constants have been derived for GeO using the DSParFit computer program. Analysis shows that the Born-Oppenheimer approximation is valid, as expected, for a molecule containing heavy atoms. The WO molecule was generated using a microwave discharge cell, and the spectra of electronic transitions of various systems were detected in emission using both the Bruker IFS 120 HR Fourier transform spectrometer at Waterloo and the McMath Pierce One-Meter Fourier transform spectrometer at the National Solar Observatory in Arizona. The ground electronic state has been confirmed to be X³&#931;<sup>-</sup> based on the analysis of seven 0-0 bands. BeH and MgH are typical molecules with hydrogen as one of their component atoms, and the effects of Born-Oppenheimer breakdown were expected. Both of these molecules have rotational perturbations in their excited electronic states. A 'new' method of data processing was used, i. e. , treating the electronic data as if they were from fluorescence series. Thus the harmful influence of the perturbed upper electronic states on the ground electronic state molecular constants is eliminated. By using the DSParFit computer program, accurate sets of combined-isotopomer Dunham-type molecular constants have been derived for the ground electronic states of the two molecules, and Born-Oppenheimer breakdown correction terms have been obtained.
8

Development of separation method for analysis of oligonucleotides using LC-UV/MS

Ida, Björs January 2018 (has links)
Introduction Oligonucleotides are short nucleic acid chains, usually 19-27mer long. They bind to their corresponding chain, making a specific inhibition possible. In pharmaceuticals, this can be used to inhibit the expression of a gene or protein of interest. Oligonucleotides are usually analyzed based on separation using both hydrophobic and ion-exchange properties. In this project, the possibility to use a mixed-mode column to separate these oligonucleotides and their impurities were explored. Method Liquid chromatography is used as the separation method and the method of detection is both mass spectrometry and UV. Three different columns are evaluated; C18, DNAPac RP, and mixed-mode RP/WAX. Results and discussion Different compositions of mobile phases and gradients are evaluated based on a literature study. Triethylamine, triethylammonium acetate, ammonium formate, hexafluoroisopropanol is used along with both methanol and acetonitrile. Phosphate buffer is evaluated on LC-UV. The results from the C18 column displays a good separation of the oligonucleotides, whilst the DNAPac RP is not as sufficient using the same mobile phases. The mixed-mode column provides good separation and selectivity using phosphate buffer and UV detection. Conclusion Mixed-mode column has the potential to be used for separation of oligonucleotides and one future focus would be to make the mobile phase compatible with mass spectrometry. Phosphate buffer and UV detection seems to be the go-to mobile phase using mixed-mode column even though MS is a more powerful tool for the characterization and identification of oligonucleotides. This provides a hint about the challenge in making the mobile phase MS compatible.

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