A medida e o controle de elementos químicos, majoritários ou traço, em tecidos e fluídos biológicos, vem sendo utilizada há muito tempo para diagnósticos médicos, em avaliações de saúde, estado nutricional e para prevenção e acompanhamento de doenças. Em muitos casos tal relação já foi solidamente estabelecida, mas no estudo de neoplasias, ainda se busca relação entre teores químicos elementares e vários tipos (ou estágios) de câncer. Nesse tipo de estudo utilizam-se métodos espectroscópicos multi-elementares de altíssima sensibilidade ainda não disponíveis rotineiramente em laboratórios clínicos. Neste trabalho, buscaram-se alterações na concentração de elementos químicos majoritários e traço em soro sanguíneo de pacientes com melanoma, por meio de análises pelos métodos PIXE e HR-ICPMS como auxiliar de diagnóstico desta neoplasia, uma vez que sua detecção em estágios iniciais aumenta a probabilidade de recuperação. A técnica PIXE (Proton Induced X-ray Emission) de análise multi-elementar baseia-se na detecção de raios X característicos, enquanto o HR-ICPMS (High Resolution Inductively Coupled Plasma Mass Spectrometry) é um espectrômetro de massa de alta resolução. As amostras de sangue de 30 pacientes e 116 doadores sadios foram coletadas no Hospital São Paulo (protocolos CEP 1036/08 UNIFESP) em tubos de vidro sem aditivos, sendo o soro separado por meio de centrifugação a 4500 rpm durante 15 minutos. Foram identificados e quantificados um total de 10 elementos: 4 por HR-ICPMS (Mg, Se, Cu e Zn) e 8 por PIXE (P, S, Cl, K, Ca, Br, Cu e Zn). Os métodos analíticos foram aferidos com os materiais de referência QMEQAS06S-06, QMEQAS08S-06 e NIST 1577b. A precisão analítica variou de 3 % a 9 % para ambas as técnicas. As informações clínicas relevantes dos pacientes foram incluídas na análise (tipo histológico do tumor; nível de melanoma; escala de Breslow em profundidade; número de linfonodos; presença ou ausência de mitose e/ou ulceração). A avaliação do grupo controle mostrou diferentes concentrações de P e Mg para indivíduos com idade acima ou abaixo de 40 anos. Os teores de P, S, Ca, Cu e Zn em indivíduos saudáveis apresentaram diferenças com o gênero, evidenciando a necessidade de inserir estas variáveis na análise caso-controle. As concentrações de K, S, Ca e Se apresentaram diferença entre os grupos controle e melanoma, quando consideradas as variáveis clínicas dos pacientes (p<0,05). A necessidade de estratificação por idade, gênero e estágio da neoplasia, reduziu criticamente o já limitado espaço amostral, comprometendo a interpretação das pequenas diferenças nas concentrações elementares encontradas. Os resultados encontrados para a população sadia concordaram com os valores publicados na literatura e colaboraram para o fortalecimento do banco de dados de concentrações elementares em soro da população brasileira. / Recording chemical elements, either as major or trace quantities, in tissues and biological fluids is regularly being used for medical diagnosis, health assessments, nutritional status, and for the monitoring and prevention of diseases. In many cases, such relationship is firmly established, but for cancer, there is still a search for a relationship between chemical elements and various types (or stages) of cancer. In this kind of study, highly sensitive multielemental spectroscopic methods are used which are not yet routinely available in clinical laboratories. In this study, changes in the concentration of chemical elements in serum of melanoma patients were sought by means of PIXE and HR-ICPMS analysis as an aid to early diagnosis, and to help increasing the likelihood of pacients recovery. The multi-elemental PIXE method (Proton Induced X-ray Emission) relies on the detection of characteristic X-rays of the sample, while the HR-ICPMS (High Resolution Inductively Coupled Plasma Mass Spectrometry) is a high resolution mass spectrometer. Blood samples from 30 patients and 116 healthy donors were collected at the Hospital (protocols CEP 1036/08 UNIFESP) in glass tubes without additives, and the serum separated after centrifugation for 15 minutes at 4500 rpm. A total of 10 elements were measured: 4 by HR-ICPMS (Mg, Se, Cu and Zn), 8 by PIXE (P, S, Cl, K, Ca, Br, Cu and Zn). The analytical methods were assessed analyzing reference materials QMEQAS06S-06, QMEQAS08S-06 and NIST 1577b. The analytical precision ranged from 3 % to 9 %. Relevant clinical information of patients has also been included in the statistical analysis (histological type of tumor, level of melanoma, Breslow depth scale, number of lymph nodes, presence or absence of mitosis and/or ulceration). The evaluation of the control group showed different concentrations of P and Mg for individuals aged above and below 40 years. The P, S, Ca, Cu and Zn in healthy individuals differed according to the gender, highlighting the need of inserting the variables age and gender in the case-control analysis. The concentrations of K, S, Ca and Se showed differences between the control group and the melanoma, when considering the clinical variables of the patients (p <0.05). The need for stratification by age, gender and stage of cancer, critically reduced the already limited number of samples, compromising the interpretation of the small differences in elemental concentrations found. The results for the healthy population agreed with the values reported in the literature and contributed to strengthen the database of elemental concentrations in serum of the Brazilian population.

<p>Radiation induced bystander effects have given the cancer risk analysis a whole new paradigm. However the actual mechanism involved in producing the effects is still not clear. The basic bystander signal is assumed to be a biological signal. In this study we proposed and tried to quantify the presence of a physical signal in the form of electromagnetic radiation that can trigger a biological response in the bystander cells. In bystander effect studies where the cells are exposed to very low fluence of charged particles there could be several regions that can produce electromagnetic radiation due to the process of atomic/molecular excitations and relaxations. We focused on quantifying the number of ultraviolet photons emitted when charged particles pass through different media that have relevance to radiation biology experiments. The choice of UV photons was made due to the reason that its effects on living cells are very well documented. For this purpose we developed a system which employed the technique of single photon counting to measure the light emitted from samples irradiated under vacuum by a charged particle beam. Photon counting was done using a fast photomultiplier tube (Hamamatsu R7400p) with a peak cathode response at 420 nm wavelength.</p> <p>In the early set of “proof of principle experiments” we tested polystyrene targets for ion beam induced luminescence. Polystyrene is one of the materials that are used as a cell substrate for radiation biology experiments. The luminescence yield from polystyrene was measured in terms of absolute value i.e. number of photons per second per unit solid angle. The output appeared to have a non-linear behavior with the incident Ion fluence: it rose exponentially to an asymptotic value. We irradiated the samples with beam energies varying from 1 MeV to 2.0 MeV and showed saturation at or before an incident fluence rate of 3×10¹³ H⁺/cm²s. The average saturation value for the photon output was found to be 40 × 10⁶ cps. Some measurements were performed using filters to study the emission at specific wavelengths. In the case of filtered light measurements, the photon output was found to saturate at 28×10³, 10×10⁶, and 35×10⁶ cps for wavelengths of 280±5 nm, 320±5 nm and 340±5 nm respectively. Using the IBIL signal evolution characteristics with the ion fluence we determined the ions produce a damage having a cross section of the order of 10^-14 cm² in polystyrene. The average radiant intensity was found to increase at wavelengths of 280 nm and 320 nm when the proton energy was increased. Having found an evidence of a significant production of UV in ion irradiated, biologically relevant, material we extended this study further into the measurements from other relevant materials in radiation biology.</p> <p>Here charged particle irradiation was performed using positively charged protons (H⁺) ranging in energy from 1.2 MeV to 2.2 MeV at a fluence rate of 2.7×10¹⁰ protons mm^-2s^-1.The materials chosen for this study were polypropylene, Mylar, Teflon, and Cellophane as they are all materials commonly used in radiation biology experiments as cell substrates or containers. In addition, we performed measurements of two NIST standard materials derived from living cells: oyster tissue and citrus leaves. These materials were measured as a powder.</p> <p>All the container materials were found to emit UV frequency photons at emission levels that are significant enough to warrant further investigation of the potential biological consequences. In addition, the NIST standard reference materials oyster tissue and citrus leaves also emitted UV when irradiated. This suggested that biological materials may themselves emit UV at significant levels when irradiated with charged particles.</p> <p>We established this further by irradiated cells with β-particles. Cells were plated in Petri-dishes of two different sizes, having different thicknesses of polystyrene (PS) substrate. Exposure of the cell substrates (polystyrene) only resulted in the production of 1035 photons per unit activity in μCi of ⁹⁰Y which was equivalent to an exposure of 840 <em>β</em>-particles/cm² to the substrate. For a collimated electron beam exposure, we observed 158-167 photons per unit μCi (18 β-particles per cm² on the substrate) for different thicknessesof the substrate. Upon irradiating HPV-G cells plated on the PS dishes we determined that the luminescence gradually increased with the increasing exposure of β-particles; reaching up to 250 % of that of the luminescence without any cells for an activity of 180 μCi. For general irradiation conditions we found statistically significant difference in luminescence output for varying cellular densities with cells only and with the application of medium on top of the cells. The colourless medium increased the total luminescence yield while the coloured medium decreased it. When the cells were irradiated using a collimated beam of electrons it was found that the luminescence decreases with the increasing cellular density thus providing an evidence of re-absorption of photons within the surroundings.</p> <p>After establishing the fact that charged particles induce light emission from the materials that have a relevance to the radiation biology experiments. We extended our study further to find out other sources of radiation that could affect the dose distribution in radiation biology experiments. In radiation biology experiments the low doses of radiation are usually delivered usingamicrobeam charged particle accelerator. Microbeams delivers a highly localized and small dose to the biological medium by using a set of collimators that confine the charged particle beam to a very narrow (micron level) region. Since the collimation block a significant proportion of the beam therefore there is a chance of the production of low energy x-rays and secondary electrons. We used Monte Carlo simulations to investigate the production of particle induced x-rays and secondary electrons in the collimation system and its possible effects on the final dose delivery to the biological medium. We found no evidence of the escape of x-rays or secondary electrons from the collimation system for proton energies of up to 3 MeV. The thickness of the collimators was sufficient to reabsorb all the generated low energy x-rays and secondary electrons. However if the proton energy exceeds 3 MeV then a significant proportion of 10 keV and 59 keV (K-α) x-rays can be emitted by the collimator. Further it was established that due to the phase space distribution of particles in various orientations with the beam axis there are significant chances of hitting non-targetted cells in microbeams that employ a collimator to confine the beam.This may happen due to the beam particles travelling obliquely with the beam axis thus passing the collimator edge and hitting the non-targetted cells. Another reason could be the scatter of beam particles inside the collimator.</p> <p>The evidence of the production of UV in materials relevant to the radiation biology experiments suggest that the conclusions and hypotheses derived from some radiation bystander experiments need to be re-thought, as charged particle irradiation leads to some level of UV emission in experimental materials which may be the cause of some “non-targeted” effects.</p> / Doctor of Philosophy (PhD)

Neste trabalhado s~ao caracterizados amostras de sedimento de vários pontos ao longo do Rio Toledo-PR, usando a técnica PIXE (Particle Induced XRays Emission), a fim de quantificar elementos traço que podem nos fornecer as possíveis fontes de poluentes deste rio. As amostras foram coletadas em seis pontos do leito do rio, durante um período de doze meses (12/2001 a 11/2002). O material coletado foi seco à temperatura ambiente, depois de peneirado e moido, e compactado em pastilhas. A irradiação das amostras foi realizada no LAMFI ( Laboratório de Análises de Materiais por Feixe Iônico) utilizando um feixe monoenergético de H+ de 2:39 MeV. A detecção dos raios X foi efetuada por um detector Si(Li) e uma eletrônica padrão. A análise dos espectros PIXE, usando o programa AXIL, nos permitiu identificar e quanti ficar alguns dos elementos presentes na amostra. As amostras analisadas são alvos grossos, assim sendo as concentrações necessitam de uma validação, para isto uma amostra referenciada (sedimento do Rio Búfalo - RM 8704) foi utilizada nos cálculos das concentrações elementares. Nas amostras analisadas foram identificados 18 elementos, sendo estes: Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr e Pb. Destes elementos decidimos monitorar os seguintes: V, Cr, Mn, Co, Ni, Cu, Zn e Pb. / In this work we characterize sediment samples from several points in the River Toledo - PR, using the PIXE (Particle Induced X-Ray Emission) spectroscopy technique, in order to quantify trace elements in these samples aiming to provide information about pollution levels for trace elements. The samples were collected in six points of river, during a period of twelve months (12/2001 to 11/2002). The collected material was air-dried at room temperature and then pressed in pellets. The samples were irradiated under vacuum using a H+ beam of 2,39MeV in the LAMFI (Laboratório de Análises de Materiais por Feixe Iônico). Produced x-rays were detected using a Si(Li) detector and a standard electronics. From analyzes of the PIXE spectra was possible to identify and quantify some elements present in the samples as well could quantify them, for this analyzes we used the Axil program to analyze the spectra. A multi-elemental referenced material (Búfalo River sediment - RM 8704) was used to validate the PIXE analysis with thick targets. Twelve months of monitoring of six river points were analyzed and these allowed us to identify 18 elements such as Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr e Pb. The elements were monitored: V, Cr, Mn, Co, Ni, Cu, Zn e Pb.

GSR ou Gunshot Residues são partículas microscópicas de resíduos provenientes da descarga de uma arma de fogo e que, em geral, ficam depositadas pelo corpo do atirador e aos arredores da cena do crime. Este trabalho tem como objetivo empregar as técnicas de PIXE (Particle-Induced X-ray Emission) convencional e -PIXE na análise da munição e GSR gerados por disparo de arma de fogo, utilizando munição de fabricação brasileira. O estudo foi dividido em duas etapas, sendo que na primeira etapa foi utilizada a técnica PIXE no estudo da composição elementar de todos os componentes (estojo, espoleta, pólvora, projétil e camisa) de dois cartuchos distintos virgens, ou seja, antes do disparo com a arma de fogo. Na segunda etapa foram efetuados os ensaios de disparo com arma de fogo, utilizando os mesmos tipos de cartuchos analisados na primeira etapa. As partículas foram coletadas e analisadas por μ-PIXE. As amostras foram irradiadas com feixes de prótons, empregando diferentes parâmetros (energia e corrente), o que depende das amostras em estudo e da técnica utilizada. Para tal fim, foi utilizado o acelerador Tandetron (modelo TN-4130-HC) disponível no Laboratório de Implantação Iônica (IF-UFRGS). Dois diferentes tipos de munição foram analisadas: CHOG e EXPO +P+. Os elementos presentes nas amostras de espoleta de ambos os tipos de munição são o alumínio, antimônio, bário e chumbo, e em menores quantidades cobre, zinco e ferro (invólucro), além de níquel no caso da munição EXPO +P+. Ambos os estojos são constituídos por cobre e zinco, apresentando adicionalmente uma grande quantidade de níquel e um pouco de ferro na munição EXPO +P+. No projétil da munição CHOG os elementos predominantes são chumbo e antimônio, além de apresentar alumínio e ferro em menores quantidades. Na munição EXPO +P+ o projétil também é constituído por chumbo, antimônio e alumínio, mas o ferro é substituído pelo cobre. As amostras de pólvora de ambos os tipos são compostas por alumínio, silício, enxofre, potássio, cálcio, titânio, cromo, níquel, ferro, cobre e zinco, e essas quantidades foram diferentes para cada tipo de munição. A pólvora CHOG apresentou bário e chumbo adicionalmente. Por último, a camisa do projétil da munição EXPO +P+ apresentou cobre, zinco, níquel, chumbo e ferro. Estes resultados são em maioria condizentes com as especificações do fabricante, a Companhia Brasileira de Cartuchos – CBC. Para a coleta das amostras de GSR, foram efetuados disparos em um anteparo de papel, onde foi fixada uma fita microporosa da marca Missner. Neste estudo, foram utilizados os dois tipos de munição analisados por PIXE. Nos dois tipos de partículas coletadas, foi possível correlacionar a presença de Ba, Pb e Sb na mesma partícula, sendo inequivocamente caracterizadas como partículas de GSR. No entanto, os resíduos apresentaram diferentes características e particularidades. Em partículas do tipo CHOG as principais características observadas foram a diferença de tamanhos, homogeneidade (exceto em alguns pontos) e ausência de formato característico. Nas partículas do tipo EXPO +P+ as características se repetem, exceto no formato que, em geral, se apresentou esférico. Comparando os resultados de PIXE e μ-PIXE, observou-se que há relação entre a munição utilizada e os resíduos de disparo produzidos, mas, no entanto as quantidades dos elementos na munição antes e depois do disparo não possuem correlação, o que pode ser explicado pela distância entre o atirador e o anteparo. Os elementos bário, chumbo e antimônio precisam de altas temperaturas para vaporizar, e não alcançariam efetivamente o anteparo a uma distância de um metro, causando grande variabilidade de concentrações entre as partículas. / GSR stands for Gunshot Residues wich are microscopic particles stemming from the discharge of a firearm. These particles are deposited on the body of the shooter and on the vicinity of the crime scene. The aim of this work is to characterize two Brazilian ammunitions and their respective GSRs using PIXE (Particle-Induced X-ray Emission) and -PIXE. Initially, the components (case, primer, gunpowder, projectile and jacket) of two pristine cartridges were analyzed by PIXE technique. Then, shooting sessions were carried out with the same cartridges. In this case, the GSR were collected for -PIXE analysis. The samples were irradiated with protons with different energies and beam currents depending on the sample under study and the technique used for analysis. To that end, a Tandetron accelerator (model TN-4130-HC) from the Ion Implantation Laboratory (IF-UFRGS) was used. The elements present in the primer for both ammunitions were aluminum, antimony, barium and lead. Other trace elements like copper, zinc and iron were present as well. Nickel was also detected in EXPO +P+ samples. The cases were made of copper and zinc. For the EXPO +P+, other elements like nickel and, to a lesser degree, iron were present as well. The bullet from CHOG ammunition was mainly composed by lead and antimony with traces of iron and aluminum. On the other hand, bullets from EXPO +P+ were characterized by lead, antimony and aluminum while iron is replaced by copper. The gunpowder from both ammunitions were characterized by aluminum, silicon, sulfur, potassium, calcium, titanium, chromium, nickel, iron, copper and zinc, and their amounts were different for each type of ammunition. In addition, the CHOG type gunpowder presented barium and lead. Finally, the jacket of the EXPO +P+ bullet has considerable amounts of copper, zinc, nickel, lead and iron. These results are compatible with the datasheet provided by the Companhia Brasileira de Cartuchos. For the study of the GSR, shootings were performed using the afore mentioned ammunitions on a paper screen with Missner tape for the collection of the ejected particles. Elements like Ba, Pb and Sb were found in the particles, thus characterizing the GSR. The CHOG particles were characterized by a large distribution of sizes and distinct shapes. On the other hand, EXPO +P+ particles were distinct due to its round shape. Comparing the results of PIXE and μ-PIXE, it was observed that there is a correlation between ammunition used and the GSR produced, but nevertheless the amounts of the elements before and after the ammunition shot does not have correlation, which can be explained the distance between the shooter and the target. The elements barium, lead and antimony require high temperatures to vaporize and not effectively reach the target at a distance of one meter, causing large variability in concentrations between particles.

GSR ou Gunshot Residues são partículas microscópicas de resíduos provenientes da descarga de uma arma de fogo e que, em geral, ficam depositadas pelo corpo do atirador e aos arredores da cena do crime. Este trabalho tem como objetivo empregar as técnicas de PIXE (Particle-Induced X-ray Emission) convencional e -PIXE na análise da munição e GSR gerados por disparo de arma de fogo, utilizando munição de fabricação brasileira. O estudo foi dividido em duas etapas, sendo que na primeira etapa foi utilizada a técnica PIXE no estudo da composição elementar de todos os componentes (estojo, espoleta, pólvora, projétil e camisa) de dois cartuchos distintos virgens, ou seja, antes do disparo com a arma de fogo. Na segunda etapa foram efetuados os ensaios de disparo com arma de fogo, utilizando os mesmos tipos de cartuchos analisados na primeira etapa. As partículas foram coletadas e analisadas por μ-PIXE. As amostras foram irradiadas com feixes de prótons, empregando diferentes parâmetros (energia e corrente), o que depende das amostras em estudo e da técnica utilizada. Para tal fim, foi utilizado o acelerador Tandetron (modelo TN-4130-HC) disponível no Laboratório de Implantação Iônica (IF-UFRGS). Dois diferentes tipos de munição foram analisadas: CHOG e EXPO +P+. Os elementos presentes nas amostras de espoleta de ambos os tipos de munição são o alumínio, antimônio, bário e chumbo, e em menores quantidades cobre, zinco e ferro (invólucro), além de níquel no caso da munição EXPO +P+. Ambos os estojos são constituídos por cobre e zinco, apresentando adicionalmente uma grande quantidade de níquel e um pouco de ferro na munição EXPO +P+. No projétil da munição CHOG os elementos predominantes são chumbo e antimônio, além de apresentar alumínio e ferro em menores quantidades. Na munição EXPO +P+ o projétil também é constituído por chumbo, antimônio e alumínio, mas o ferro é substituído pelo cobre. As amostras de pólvora de ambos os tipos são compostas por alumínio, silício, enxofre, potássio, cálcio, titânio, cromo, níquel, ferro, cobre e zinco, e essas quantidades foram diferentes para cada tipo de munição. A pólvora CHOG apresentou bário e chumbo adicionalmente. Por último, a camisa do projétil da munição EXPO +P+ apresentou cobre, zinco, níquel, chumbo e ferro. Estes resultados são em maioria condizentes com as especificações do fabricante, a Companhia Brasileira de Cartuchos – CBC. Para a coleta das amostras de GSR, foram efetuados disparos em um anteparo de papel, onde foi fixada uma fita microporosa da marca Missner. Neste estudo, foram utilizados os dois tipos de munição analisados por PIXE. Nos dois tipos de partículas coletadas, foi possível correlacionar a presença de Ba, Pb e Sb na mesma partícula, sendo inequivocamente caracterizadas como partículas de GSR. No entanto, os resíduos apresentaram diferentes características e particularidades. Em partículas do tipo CHOG as principais características observadas foram a diferença de tamanhos, homogeneidade (exceto em alguns pontos) e ausência de formato característico. Nas partículas do tipo EXPO +P+ as características se repetem, exceto no formato que, em geral, se apresentou esférico. Comparando os resultados de PIXE e μ-PIXE, observou-se que há relação entre a munição utilizada e os resíduos de disparo produzidos, mas, no entanto as quantidades dos elementos na munição antes e depois do disparo não possuem correlação, o que pode ser explicado pela distância entre o atirador e o anteparo. Os elementos bário, chumbo e antimônio precisam de altas temperaturas para vaporizar, e não alcançariam efetivamente o anteparo a uma distância de um metro, causando grande variabilidade de concentrações entre as partículas. / GSR stands for Gunshot Residues wich are microscopic particles stemming from the discharge of a firearm. These particles are deposited on the body of the shooter and on the vicinity of the crime scene. The aim of this work is to characterize two Brazilian ammunitions and their respective GSRs using PIXE (Particle-Induced X-ray Emission) and -PIXE. Initially, the components (case, primer, gunpowder, projectile and jacket) of two pristine cartridges were analyzed by PIXE technique. Then, shooting sessions were carried out with the same cartridges. In this case, the GSR were collected for -PIXE analysis. The samples were irradiated with protons with different energies and beam currents depending on the sample under study and the technique used for analysis. To that end, a Tandetron accelerator (model TN-4130-HC) from the Ion Implantation Laboratory (IF-UFRGS) was used. The elements present in the primer for both ammunitions were aluminum, antimony, barium and lead. Other trace elements like copper, zinc and iron were present as well. Nickel was also detected in EXPO +P+ samples. The cases were made of copper and zinc. For the EXPO +P+, other elements like nickel and, to a lesser degree, iron were present as well. The bullet from CHOG ammunition was mainly composed by lead and antimony with traces of iron and aluminum. On the other hand, bullets from EXPO +P+ were characterized by lead, antimony and aluminum while iron is replaced by copper. The gunpowder from both ammunitions were characterized by aluminum, silicon, sulfur, potassium, calcium, titanium, chromium, nickel, iron, copper and zinc, and their amounts were different for each type of ammunition. In addition, the CHOG type gunpowder presented barium and lead. Finally, the jacket of the EXPO +P+ bullet has considerable amounts of copper, zinc, nickel, lead and iron. These results are compatible with the datasheet provided by the Companhia Brasileira de Cartuchos. For the study of the GSR, shootings were performed using the afore mentioned ammunitions on a paper screen with Missner tape for the collection of the ejected particles. Elements like Ba, Pb and Sb were found in the particles, thus characterizing the GSR. The CHOG particles were characterized by a large distribution of sizes and distinct shapes. On the other hand, EXPO +P+ particles were distinct due to its round shape. Comparing the results of PIXE and μ-PIXE, it was observed that there is a correlation between ammunition used and the GSR produced, but nevertheless the amounts of the elements before and after the ammunition shot does not have correlation, which can be explained the distance between the shooter and the target. The elements barium, lead and antimony require high temperatures to vaporize and not effectively reach the target at a distance of one meter, causing large variability in concentrations between particles.

Neste trabalhado s~ao caracterizados amostras de sedimento de vários pontos ao longo do Rio Toledo-PR, usando a técnica PIXE (Particle Induced XRays Emission), a fim de quantificar elementos traço que podem nos fornecer as possíveis fontes de poluentes deste rio. As amostras foram coletadas em seis pontos do leito do rio, durante um período de doze meses (12/2001 a 11/2002). O material coletado foi seco à temperatura ambiente, depois de peneirado e moido, e compactado em pastilhas. A irradiação das amostras foi realizada no LAMFI ( Laboratório de Análises de Materiais por Feixe Iônico) utilizando um feixe monoenergético de H+ de 2:39 MeV. A detecção dos raios X foi efetuada por um detector Si(Li) e uma eletrônica padrão. A análise dos espectros PIXE, usando o programa AXIL, nos permitiu identificar e quanti ficar alguns dos elementos presentes na amostra. As amostras analisadas são alvos grossos, assim sendo as concentrações necessitam de uma validação, para isto uma amostra referenciada (sedimento do Rio Búfalo - RM 8704) foi utilizada nos cálculos das concentrações elementares. Nas amostras analisadas foram identificados 18 elementos, sendo estes: Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr e Pb. Destes elementos decidimos monitorar os seguintes: V, Cr, Mn, Co, Ni, Cu, Zn e Pb. / In this work we characterize sediment samples from several points in the River Toledo - PR, using the PIXE (Particle Induced X-Ray Emission) spectroscopy technique, in order to quantify trace elements in these samples aiming to provide information about pollution levels for trace elements. The samples were collected in six points of river, during a period of twelve months (12/2001 to 11/2002). The collected material was air-dried at room temperature and then pressed in pellets. The samples were irradiated under vacuum using a H+ beam of 2,39MeV in the LAMFI (Laboratório de Análises de Materiais por Feixe Iônico). Produced x-rays were detected using a Si(Li) detector and a standard electronics. From analyzes of the PIXE spectra was possible to identify and quantify some elements present in the samples as well could quantify them, for this analyzes we used the Axil program to analyze the spectra. A multi-elemental referenced material (Búfalo River sediment - RM 8704) was used to validate the PIXE analysis with thick targets. Twelve months of monitoring of six river points were analyzed and these allowed us to identify 18 elements such as Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr e Pb. The elements were monitored: V, Cr, Mn, Co, Ni, Cu, Zn e Pb.

GSR ou Gunshot Residues são partículas microscópicas de resíduos provenientes da descarga de uma arma de fogo e que, em geral, ficam depositadas pelo corpo do atirador e aos arredores da cena do crime. Este trabalho tem como objetivo empregar as técnicas de PIXE (Particle-Induced X-ray Emission) convencional e -PIXE na análise da munição e GSR gerados por disparo de arma de fogo, utilizando munição de fabricação brasileira. O estudo foi dividido em duas etapas, sendo que na primeira etapa foi utilizada a técnica PIXE no estudo da composição elementar de todos os componentes (estojo, espoleta, pólvora, projétil e camisa) de dois cartuchos distintos virgens, ou seja, antes do disparo com a arma de fogo. Na segunda etapa foram efetuados os ensaios de disparo com arma de fogo, utilizando os mesmos tipos de cartuchos analisados na primeira etapa. As partículas foram coletadas e analisadas por μ-PIXE. As amostras foram irradiadas com feixes de prótons, empregando diferentes parâmetros (energia e corrente), o que depende das amostras em estudo e da técnica utilizada. Para tal fim, foi utilizado o acelerador Tandetron (modelo TN-4130-HC) disponível no Laboratório de Implantação Iônica (IF-UFRGS). Dois diferentes tipos de munição foram analisadas: CHOG e EXPO +P+. Os elementos presentes nas amostras de espoleta de ambos os tipos de munição são o alumínio, antimônio, bário e chumbo, e em menores quantidades cobre, zinco e ferro (invólucro), além de níquel no caso da munição EXPO +P+. Ambos os estojos são constituídos por cobre e zinco, apresentando adicionalmente uma grande quantidade de níquel e um pouco de ferro na munição EXPO +P+. No projétil da munição CHOG os elementos predominantes são chumbo e antimônio, além de apresentar alumínio e ferro em menores quantidades. Na munição EXPO +P+ o projétil também é constituído por chumbo, antimônio e alumínio, mas o ferro é substituído pelo cobre. As amostras de pólvora de ambos os tipos são compostas por alumínio, silício, enxofre, potássio, cálcio, titânio, cromo, níquel, ferro, cobre e zinco, e essas quantidades foram diferentes para cada tipo de munição. A pólvora CHOG apresentou bário e chumbo adicionalmente. Por último, a camisa do projétil da munição EXPO +P+ apresentou cobre, zinco, níquel, chumbo e ferro. Estes resultados são em maioria condizentes com as especificações do fabricante, a Companhia Brasileira de Cartuchos – CBC. Para a coleta das amostras de GSR, foram efetuados disparos em um anteparo de papel, onde foi fixada uma fita microporosa da marca Missner. Neste estudo, foram utilizados os dois tipos de munição analisados por PIXE. Nos dois tipos de partículas coletadas, foi possível correlacionar a presença de Ba, Pb e Sb na mesma partícula, sendo inequivocamente caracterizadas como partículas de GSR. No entanto, os resíduos apresentaram diferentes características e particularidades. Em partículas do tipo CHOG as principais características observadas foram a diferença de tamanhos, homogeneidade (exceto em alguns pontos) e ausência de formato característico. Nas partículas do tipo EXPO +P+ as características se repetem, exceto no formato que, em geral, se apresentou esférico. Comparando os resultados de PIXE e μ-PIXE, observou-se que há relação entre a munição utilizada e os resíduos de disparo produzidos, mas, no entanto as quantidades dos elementos na munição antes e depois do disparo não possuem correlação, o que pode ser explicado pela distância entre o atirador e o anteparo. Os elementos bário, chumbo e antimônio precisam de altas temperaturas para vaporizar, e não alcançariam efetivamente o anteparo a uma distância de um metro, causando grande variabilidade de concentrações entre as partículas. / GSR stands for Gunshot Residues wich are microscopic particles stemming from the discharge of a firearm. These particles are deposited on the body of the shooter and on the vicinity of the crime scene. The aim of this work is to characterize two Brazilian ammunitions and their respective GSRs using PIXE (Particle-Induced X-ray Emission) and -PIXE. Initially, the components (case, primer, gunpowder, projectile and jacket) of two pristine cartridges were analyzed by PIXE technique. Then, shooting sessions were carried out with the same cartridges. In this case, the GSR were collected for -PIXE analysis. The samples were irradiated with protons with different energies and beam currents depending on the sample under study and the technique used for analysis. To that end, a Tandetron accelerator (model TN-4130-HC) from the Ion Implantation Laboratory (IF-UFRGS) was used. The elements present in the primer for both ammunitions were aluminum, antimony, barium and lead. Other trace elements like copper, zinc and iron were present as well. Nickel was also detected in EXPO +P+ samples. The cases were made of copper and zinc. For the EXPO +P+, other elements like nickel and, to a lesser degree, iron were present as well. The bullet from CHOG ammunition was mainly composed by lead and antimony with traces of iron and aluminum. On the other hand, bullets from EXPO +P+ were characterized by lead, antimony and aluminum while iron is replaced by copper. The gunpowder from both ammunitions were characterized by aluminum, silicon, sulfur, potassium, calcium, titanium, chromium, nickel, iron, copper and zinc, and their amounts were different for each type of ammunition. In addition, the CHOG type gunpowder presented barium and lead. Finally, the jacket of the EXPO +P+ bullet has considerable amounts of copper, zinc, nickel, lead and iron. These results are compatible with the datasheet provided by the Companhia Brasileira de Cartuchos. For the study of the GSR, shootings were performed using the afore mentioned ammunitions on a paper screen with Missner tape for the collection of the ejected particles. Elements like Ba, Pb and Sb were found in the particles, thus characterizing the GSR. The CHOG particles were characterized by a large distribution of sizes and distinct shapes. On the other hand, EXPO +P+ particles were distinct due to its round shape. Comparing the results of PIXE and μ-PIXE, it was observed that there is a correlation between ammunition used and the GSR produced, but nevertheless the amounts of the elements before and after the ammunition shot does not have correlation, which can be explained the distance between the shooter and the target. The elements barium, lead and antimony require high temperatures to vaporize and not effectively reach the target at a distance of one meter, causing large variability in concentrations between particles.

Etudier le rôle des éléments traces à l’échelle cellulaire requiert des outils analytiques de pointe. Nous avons développé une nouvelle méthodologie précise de la répartition des éléments chimiques cellulaires à partir d’une combinaison des méthodes d’analyse par faisceaux d’ions PIXE, RBS et STIM. Cette méthodologie s’appuie fortement sur le développement d’un logiciel (Paparamborde) pour le traitement quantitatif des expériences STIM. La validité de cette méthode ainsi que ses limites sont discutées. La méthode STIM-PIXE-RBS permet de quantifier la composition en éléments traces (µg/g) avec une incertitude de mesure évaluée à 19,8% dans des compartiments cellulaires de masse inférieure à 0,1 ng.Une des limites de la méthode réside dans le faible nombre d’échantillons analysables en raison à la fois du temps minimum nécessaire pour réaliser une acquisition et de l’accès limité aux plateformes d’analyse par faisceaux d’ions. C’est pourquoi nous avons également développé une base de données pour la capitalisation des compositions chimiques cellulaires (BDC4). Cette base de données s’inscrit dans la logique de l’utilisation de la composition chimique cellulaire comme un traceur de l’activité biologique, et doit permettre à terme de définir des compositions chimiques de référence pour les différents types cellulaires analysés.L’application de la méthodologie STIM-PIXE-RBS à l’étude de la toxicologie nucléaire du cobalt permet d’illustrer son intérêt en pratique. En particulier, l’analyse STIM s’avère indispensable dans le cas d’échantillons présentant une perte de masse organique au cours de l’analyse PIXE-RBS. / The study of the role of trace elements at cellular level requires the use of state-of-the-art analytical tools that could achieve enough sensitivity and spatial resolution. We developed a new methodology for the accurate quantification of chemical element distribution in single cells based on a combination of ion beam analysis techniques STIM, PIXE and RBS. The quantification procedure relies on the development of a STIM data analysis software (Paparamborde). Validity of this methodology and limits are discussed here. The method allows the quantification of trace elements (µg/g) with a 19.8 % uncertainty in cellular compartments with mass below 0.1 ng.The main limit of the method lies in the poor number of samples that can be analyzed, due to long irradiation times required and limited access to ion beam analysis facilities. This is the reason why we developed a database for cellular chemical composition capitalization (BDC4). BDC4 has been designed in order to use cellular chemical composition as a tracer for biological activities and is expected to provide in the future reference chemical compositions for any cellular type or compartment.Application of the STIM-PIXE-RBS methodology to the study of nuclear toxicology of cobalt compounds is presented here showing that STIM analysis is absolutely needed when organic mass loss appears during PIXE-RBS irradiation.

Une première partie de ce mémoire portera sur l’analyse des états fondamentaux ma- gnétiques de deux composés isolants et magnétiquement frustrés SrDy2O4 et SrHo2O4. Une étude de la chaleur spécifique à basse température sous l’effet de champs magné- tiques de ces échantillons a été menée afin de détecter la présence de transitions de phases. L’utilisation d’un composé isotructurel non magnétique, le SrLu2O4, a permis l’isolement de la composante magnétique à la chaleur spécifique. Les comportements observés sont non conformes avec les transitions magnétiques conventionnelles. De plus, le calcul de l’entropie magnétique ne montre qu’un recouvrement partiel de l’entropie associée à un système d’ions magnétiques. En second lieu, une analyse des oscillations quantiques de Haas-van Alphen a été effectuée dans le LuCoIn5, composé apparenté au supraconducteur à fermions lourds CeCoIn5. Les résultats obtenus montrent une topologie de la surface de Fermi très différente comparativement aux CeCoIn5 et LaCoIn5, ayant un comportement beaucoup plus tridimensionnel sans les cylindres caractéristiques présents chez les autres membres de cette famille. Finalement, le montage d’un système de détection PIXE a permis l’analyse nucléaire d’échantillons afin de déterminer la concentration de chacun des éléments les constituant. L’analyse a été effectuée sur une série d’échantillons YbxCe1−xCoIn5 dont le changement de concentration a des effets importants sur les propriétés du système. / The first part of this thesis consist of the analysis the magnetic ground states of two magnetically frustrated insulator compounds SrDy2O4 and SrHo2O4. A study of the low temperature specific heat in magnetic fields has been carried on in order to detect phase transitions. The magnetic contribution to the specific heat has been determined using the isostructural but non magnetic compound SrLu2O4. The observed behaviour does not conform with conventional magnetic phase transitions. Also, the calculated magnetic entropy shows only a partial recovery of the entropy normally associated with magnetic ions in the systems. In the second study, I measured and analyzed de Haas-van Alphen quantum oscil- lations in LuCoIn5, a compound related to the heavy fermion superconductor CeCoIn5. The obtained results show a Fermi surface topology greatly differing from the CeCoIn5 and LaCoIn5, having a much more tridimensional behaviour, compared to the characteristics cylinder exhibited by the other members of this family. In the last part of my thesis, I’m am describing the set up of a PIXE detection system used for the nuclear analysis of thick samples in order to calculate the concentra- tion of each element present. The analysis has been carried on a series of samples of YbxCe1−xCoIn5, where the variation of concentration has major repercussions on the electronic and magnetic properties of the system.

Les verres bioactifs sont des matériaux particulièrement intéressants en régénération osseuse du fait de leur capacité à stimuler les cellules responsables de la croissance osseuse par les espèces qu’ils relarguent lors de leur dissolution et pour leur capacité à se lier à l’os. Au-delà de leur rôle comme matériau de comblement de défauts osseux, ils pourraient servir de support à la croissance en laboratoire de véritables greffons osseux cultivés à l’aide de seulement quelques cellules d’un patient. Afin d’être efficace, ce support doit posséder une architecture macroporeuse interconnectée pour permettre l’invasion cellulaire ainsi que la vascularisation, nécessaire à la survie des cellules. Ce travail de thèse a pour objectif la réalisation d’un tel support par l’ajout d’une étape de moussage au procédé sol-gel. Ce procédé a été utilisé pour la synthèse de matériaux aux porosités différentes permettant de déterminer une porosité plus prometteuse pour des essais in vivo qui ont montré l’invasion possible de cette mousse par des cellules osseuses. Ce procédé a de plus été rendu plus sûr par la mise au point d’une voie de synthèse alternative dans laquelle l’acide nécessaire au procédé de moussage, mais toxique, a été remplacé avec succès. Cette voie alternative a de plus permis l’organisation de la mésoporosité de la mousse. L’incorporation d’un élément d’intérêt biologique, le strontium, a été réalisé et son influence sur les propriétés et la réactivité du verre a été étudiée. Enfin, une voie de synthèse de nouveaux matériaux composites a été proposée : la grande bioactivité des verres bioactifs est conservée tout en ayant des propriétés mécaniques supérieures grâce à l’utilisation de la gélatine comme phase organique. / Bioactive glasses are very interesting materials for bone regeneration because of their ability to stimulate cells responsible for bone growth with ionic products released during dissolution and for their bone bonding ability. Beyond their role as bone filling materials, they can be used as support for growth of laboratory-made bone grafts cultivated from just a few cells of a patient. This support, named scaffold, has to be an interconnected macroporous architecture in order to allow cell invasion and vascularization which is essential to cell survival. The aim of this thesis work is the realization of such a scaffold using the sol-gel foaming process. This process has been used for the synthesis of materials with different properties that were compared for determination of the most promising for in vivo implantation and was indeed able to allow cell invasion. Moreover, this process was improved to be safer by replacement of hazardous catalyst. This new process also allowed the structuration of the mesoporosity inside the foams. Incorporation of a biologically active element (strontium) was realized and its influence on the glass properties and reactivity was evaluated. Finally, the synthesis of new composite materials has been proposed: the high bioactivity of bioactive glasses is preserved while better mechanical properties are obtained thank to the use of gelatin as organic phase.