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Estudo teórico da relação entre número de CT de raios-X e Stopping Power de prótonsInocente, Guilherme Franco [UNESP] 01 March 2012 (has links) (PDF)
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000709627.pdf: 615342 bytes, checksum: ecb29e15c1848924480b318430ee4378 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Um dos métodos mais utilizados para tratamento de câncer e o uso da radiação. Nesse contexto surge a terapia com feixes de prótons em frente a radioterapia convencional. Sabe-se que com a protonterapia há mais vantagens para o paciente tratado quando comparada com os métodos mais convencionais. A dose distribuída ao longo do caminho percorrido, principalmente nos tecidos sadios - região vizinha ao tumor, e menor e a acurácia do tratamento é muito melhor. Para a realização do tratamento, o paciente passa por alguns procedimentos e um deles é realizar uma imagem para visualização e localização do volume alvo. O principal método para obter essas imagens e a tomografia computadorizada de raios-X (XCT). Para o tratamento com feixes de prótons essa técnica de imagem pode gerar algumas incertezas. A proposta deste estudo é analisar a viabilidade de se reconstruir imagens geradas a partir da irradiação com feixes de prótons, e com isso diminuir algumas imprecisões, já que ser a o mesmo tipo de radiação para planejamento como tratamento, é também para diminuir drasticamente alguns erros de localização, uma vez que o planejamento poder a ser feito no mesmo local e em instantes antes onde o paciente ser a tratado. Este trabalho tem por finalidade, obter uma rela ção entre a propriedade intrínseca da interação de fótons e prótons com a matéria. Para isso utilizaremos de simulação computacional baseada no método de Monte Carlo, com os códigos SRIM 2008 e MCNPX v.2.5.0, para reconstruir imagens através da técnica utilizada na tomografia computadorizada convencional / The radiation method is one of the most used for cancer treatment. In this context arises therapy with proton beams in front of conventional radiotherapy. It is known that with protontherapy there are more advantages to the patient treatement when compared with more conventional methods. The dose distributed along the path, especially in healthy tissues neighbor the tumor, is smaller and the accuracy of treatment is much better. To carry out the treatment, the patient undergoes a plan through images for visualization and location of the target volume. The main method for obtaining these images is computed tomography X-ray (XCT). For treatment with proton beam this imaging technique can to generate some uncertainties. The purpose of this study is to analyse the feasibility of reconstructing images generated from the irradiation with proton beams, thereby reducing some inaccuracies, as it will be the same type of radiation as treatment planning, and also to drastically reduce some errors location, since the planning can be done at the same place and just before where the patient is treated. This study aims to obtain a relationship between the intrinsic property of the interaction of photons and protons with matter. For this we use computational simulation based on Monte Carlo method with the code SRIM 2008 and MCNPX v.2.5.0, to reconstruct images using the technique used in conventional computed tomography
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Estudo teórico da relação entre número de CT de raios-X e Stopping Power de prótons /Inocente, Guilherme Franco. January 2012 (has links)
Orientador: Joel Mesa Hormaza / Banca: Roberto Morato Fernandez / Banca: João Dias de Toledo Arruda Neto / Resumo: Um dos métodos mais utilizados para tratamento de câncer e o uso da radiação. Nesse contexto surge a terapia com feixes de prótons em frente a radioterapia convencional. Sabe-se que com a protonterapia há mais vantagens para o paciente tratado quando comparada com os métodos mais convencionais. A dose distribuída ao longo do caminho percorrido, principalmente nos tecidos sadios - região vizinha ao tumor, e menor e a acurácia do tratamento é muito melhor. Para a realização do tratamento, o paciente passa por alguns procedimentos e um deles é realizar uma imagem para visualização e localização do volume alvo. O principal método para obter essas imagens e a tomografia computadorizada de raios-X (XCT). Para o tratamento com feixes de prótons essa técnica de imagem pode gerar algumas incertezas. A proposta deste estudo é analisar a viabilidade de se reconstruir imagens geradas a partir da irradiação com feixes de prótons, e com isso diminuir algumas imprecisões, já que ser a o mesmo tipo de radiação para planejamento como tratamento, é também para diminuir drasticamente alguns erros de localização, uma vez que o planejamento poder a ser feito no mesmo local e em instantes antes onde o paciente ser a tratado. Este trabalho tem por finalidade, obter uma rela ção entre a propriedade intrínseca da interação de fótons e prótons com a matéria. Para isso utilizaremos de simulação computacional baseada no método de Monte Carlo, com os códigos SRIM 2008 e MCNPX v.2.5.0, para reconstruir imagens através da técnica utilizada na tomografia computadorizada convencional / Abstract: The radiation method is one of the most used for cancer treatment. In this context arises therapy with proton beams in front of conventional radiotherapy. It is known that with protontherapy there are more advantages to the patient treatement when compared with more conventional methods. The dose distributed along the path, especially in healthy tissues ���� neighbor the tumor, is smaller and the accuracy of treatment is much better. To carry out the treatment, the patient undergoes a plan through images for visualization and location of the target volume. The main method for obtaining these images is computed tomography X-ray (XCT). For treatment with proton beam this imaging technique can to generate some uncertainties. The purpose of this study is to analyse the feasibility of reconstructing images generated from the irradiation with proton beams, thereby reducing some inaccuracies, as it will be the same type of radiation as treatment planning, and also to drastically reduce some errors location, since the planning can be done at the same place and just before where the patient is treated. This study aims to obtain a relationship between the intrinsic property of the interaction of photons and protons with matter. For this we use computational simulation based on Monte Carlo method with the code SRIM 2008 and MCNPX v.2.5.0, to reconstruct images using the technique used in conventional computed tomography / Mestre
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Nuclear reaction studies at low energiesBearpark, K. January 1964 (has links)
No description available.
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An algorithm for two-dimensional density reconstruction in proton computed tomography (PCT)Tafas, Jihad 01 January 2007 (has links)
The purpose of this thesis is to develop an optimized and effective iterative reconstruction algorithm and hardware acceleration methods that work synonymously together through reconstruction in proton computed tomography, which accurately maps the electron density.
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Interference effects due to projective-target nucleus scattering in single ionization of molecular hydrogen by 75 keV proton impactAlexander, Jason S. January 2009 (has links) (PDF)
Thesis (Ph. D.)--Missouri University of Science and Technology, 2009. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed April 27, 2009) Includes bibliographical references (p. 70-74).
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Elastic scattering of 30-Mev protonsLeahy, John. January 1956 (has links)
Thesis--University of California, Berkely. / "Physics Distribution." Includes bibliographical references (p. 37-38). 45
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Optimized and integrated alignment system for functional proton radiosurgeryShihadeh, Fadi Easa 01 January 2007 (has links)
In this thesis work, a system for proton beam alignment was studied and optimized in many of its functional areas. The resulting system was named Positioning Alignment Control System (PACS). The PACS system is an integrated and efficient system as a result of the work done on it in the course of this thesis work.
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Estudo da interação de prótons com alvos não homogêneos, aplicados a tomografia com feixes de prótons /Roder, Ana Flávia Vidotti. January 2014 (has links)
Orientador: Joel Mesa Hormaza / Banca: Hélio Yoriyaz / Banca: Paulo de Tarso Siqueira / Resumo: O tratamento do câncer através da irradiação com prótons tem se desenvolvido a amplamente, de maneira que a cada década o número de centros com essa tecnologia aumenta progressivamente. Entretanto, o planejamento da rotina de terapia ainda é realizado com imagens de raios-X, que pode causar incertezas quanto ao posicionamento preciso do feixe de prótons sobre o tumor devido à diferença de comportamento ao interagir com a matéria. Por isso, são necessários estudos que busquem o aprimoramento da tomografia computadorizada com prótons, que tem como principal função, determinar a posição do pico de Bragg com eficiência. Mas para se desenvolver essa técnica é preciso determinar a trajetória exata que a partícula percorre dentro do corpo do paciente, que é possível com simulações baseadas no método de Monte Carlo. Vários programas no mercado utilizam Monte Carlo para diferentes tipos de propósitos, dentre os que são voltados para o transporte do próton, estão: GEANT, FLUKA e MCNPX. Esse último foi o utilizado neste trabalho para avaliar a perturbação no feixe incidente de prótons em um meio heterogêneo, composto por água e material simulador de osso compacto (interfaces perpendiculares ao feixe). Além de um modelo formado por água e PMMA (interfases paralelas ao feixe) para avaliar o uso de fantomas desses materiais. Foram estudadas energia, posição e ângulo de saída dos prótons considerando somente partículas primárias e também para todas as partículas / Abstract: Cancer treatment by irradiation with protons has been widely developed so that each decade the number of centers based on this technology increases progressively. However, the planning of routine therapy is performed with images of X- rays, which can cause uncertainties as to the precise positioning of the proton beam on the tumor due to the difference in behavior when interacting with matter. Therefore, it is necessary studying the improvement of computed tomography with protons, whose main function, determine the position of the Bragg peak efficiently. Nevertheless, to develop this technique it is necessary to determine the exact path that the particle travels through the patient's body, which is possible with simulations based on Monte Carlo method. There are several programs that use Monte Carlo for different types of purposes, among which are meant for the transport of the proton: GEANT, FLUKA and MCNPX. The third one was used in this work to evaluate the disturbance in the incident beam of protons in a heterogeneous medium composed of water and equipment simulator compact bone (beam direction perpendicular to the interface) and water-PMMA (beam parallel to the interface). The output energy, position and angle of the protons were studied considering only primary particles and for all particles / Mestre
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Production of radionuclides with medium energy protons with the emphasis on targetryVermeulen, Christiaan 12 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The facilities for radionuclide production at iThemba LABS have undergone a number of significant upgrades
over the last decade in order to increase the production capacity and to diversify the product
portfolio. Central to this effort is a new vertical beam target station (VBTS) and its associated targetry,
designed and built to operate at higher proton beam intensities for the large-scale production of relatively
long-lived, high-value radionuclides such as 22Na, 68Ge and 82Sr. Along with the VBTS, an existing smaller
horizontal beam target station was adapted to accommodate targetry for 18F production, mainly to supply
18F-FDG for use in positron emission tomography (PET). The production capacity was further enhanced
by means of a beam splitter to enable bombardments in two target stations simultaneously. This required
new developments on several systems, e.g. beam diagnostics, control, interlocking and cooling.
This project brings together a number of different aspects of the upgraded facilities as well as the
associated research and development that enable the production of radionuclides in the medium energy
region, up to approximately 70 MeV. Investigations were performed on the cooling of the interfacial windows
between the cyclotron vacuum and the targets as well as the direct cooling of the targets themselves
during intense proton bombardments. For this purpose, empirical as well as computational fluid dynamics
(CFD) calculations were performed. In addition, the local radiation shield of the VBTS as well as the
beam transport in some of the targetry was investigated by means of Monte Carlo radiation transport
calculations.
Excitation functions for the production of various radionuclides in the 66 MeV proton bombardment
of 192Os, 159Tb, natGd, 155Gd, 152Gd, 93Nb, natZr and 89Y were measured and compared with theoretical
predictions by means of statistical nuclear model calculations as well as the TENDL-2012 library. In
particular, the production of 186Re, selected radioterbiums (149;152;155Tb) and radiozirconiums (88;89Zr) is of
interest in existing and emerging diagnostic and therapeutic applications in nuclear medicine. A study on
28Mg production in the proton bombardment of natCl using stacked chloride targets was also performed
at 200 MeV. This radionuclide is of interest as 28Mg is the only practical radiotracer of Mg. Finally, new
targetry for the production of 18F was developed, modelled and optimized for the non-standard degraded
beam employed in this particular case. / AFRIKAANSE OPSOMMING: Die fasiliteite vir die produksie van radionukliede by iThemba LABS is gedurende die afgelope dekade
aansienlik opgegradeer om die produksiekapasiteit te verhoog en om die portfolio van produkte te diversifiseer.
Sentraal tot hierdie poging is ’n vertikale-bundel skyfstasie (VBTS) wat gebou is om skywe
met hoër intensiteit protonbundels te bombardeer ten einde relatief langlewende, hoë-waarde radionukliede
op grootmaat te produseer, insluitende 22Na, 68Ge en 82Sr. Terselfdetyd is ’n bestaande, kleiner
horisontale-bundel skyfstasie aangepas om skywe vir die produksie van 18F te huisves, meestal om 18FFDG
vir positronemissietomografie (PET) te lewer. Die produksiekapasiteit is verder verhoog d.m.v. ’n
bundeldeler sodat bundel gelyktyding aan twee skyfstasies gelewer kan word. Dit het ontwikkelingswerk
vereis aan verskeie stelsels, insluitende diagnostiek, beheer, vergrendeling en verkoeling.
Hierdie projek bring verskeie aspekte bymekaar t.o.v. die opgegradeerde produksiefasiliteite sowel as
die geassosieerde navorsing en ontwikkeling benodig vir radionukliedproduksie in die middelenergiegebied
tot ongeveer 70 MeV. Die verkoeling van die foelievensters tussen die vakuum van die siklotron
en die skyfgerei is ondersoek sowel as die direkte verkoeling van skywe onder intense protonbombardement.
Hierdie studie sluit beide empiriese sowel as numeriese vloeidinamika berekeninge in. Verder is
die afskerming van die VBTS asook die bundeltransport in verskeie skywe ondersoek m.b.v. Monte Carlo
stralingstransport berekeninge.
Opwekkrommes vir die produksie van verskeie radionukliede met protongeïnduseerde reaksies tot en
met 66 MeV op 192Os, 159Tb, natGd, 155Gd, 152Gd, 93Nb, natZr en 89Y is gemeet en vergelyk met statistiese
kernmodel berekeninge sowel as die TENDL-2012 biblioteek. Die produksie van 186Re, verskeie radioterbiums
(149;152;155Tb) en radiozirkoniums (88;89Zr) is van spesifieke belang vir bestaande en toekomstige
diagnostiese en terapeutiese toepassings in die kerngeneeskunde. ’n Studie op die produksie van 28Mg in
die bombardement van natCl met 200 MeV protone is ook onderneem. In hierdie ondersoek is ’n stapel
chloriedskywe gebruik. Die 28Mg is van belang omdat dit die enigste Mg radioisotoop is wat geskik is
as ’n radiospoorder van dié element. Laastens is nuwe skyfgerei vir die produksie van 18F ontwikkel,
gemodelleer en geoptimiseer vir die nie-standaard afgeremde bundel wat benut word in hierdie geval.
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Analogue readout and signal processing for micro strip gas chambers of the compact muon solenoid at LHCSciacca, Francesco G. P. January 1999 (has links)
No description available.
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