Are we following the guidelines on non-muscle invasive bladder cancer?

To evaluate the clinical practice of non-muscle invasive bladder cancer (NMIBC) treatment in Brazil in relation to international guidelines: Sociedade Brasileira de Urologia (SBU), European Association of Urology (EAU) and American Urological Association (AUA). Cross-sectional study using questionnaires about urological practice on treatment of NMIBC during the 32nd Brazilian Congress of Urology. A total of 650 question forms were answered. There were 73% of complete answers (total of 476 question forms). In total, 246 urologists (51.68%) lived in the southeast region and 310 (65.13%) treat 1 to 3 cases of NMIBC per month. Low risk cancer: Only 35 urologists (7.5%) apply the single intravesical dose of immediate chemotherapy with Mitomicin C recommended by the above guidelines. Adjuvant therapy with BCG 2 to 4 weeks after TUR is used by 167 participants (35.1%) and 271 urologists (56.9%) use only TUR. High risk tumors: 397 urologists (83.4%) use adjuvant therapy, 375 (78.8%) use BCG 2 to 4 weeks after TUR, of which 306 (64.3%) referred the use for at least one year. Intravesical chemotherapy with Mitomicin C (a controversial recommendation) was used by 22 urologists (4.6%). BCG dose raised a lot of discrepancies. Induction doses of 40, 80 and 120mg were referred by 105 (22%), 193 (40.4%) and 54 (11.3%) respectively. Maintenance doses of 40, 80 and 120mg were referred by 190 (48.7%), 144 (37.0%) and 32 (8.2%) urologists, respectively. Schemes of administration were also varied and the one cited by SWOG protocol was the most used: 142 (29.8%). SBU, EAU and AUA guidelines are partially respected by Brazilian urologists, particularly in low risk tumors. In high risk tumors, concordance rates are comparable to international data. Further studies are necessary to fully understand the reasons of such disagreement421222

Perda de energia de íons leves (H+ e He+) na matéria: medidas de alta acurácia e comparação com o modelo de FEG

The phenomenon of energy loss that occurs when an ion interacts with matter, also called stopping power, has been investigated for more than a century, and has provided findings of interest. However, reliable procedures for obtaining accurate experimental measurements and a fully theoretical comprehension of the process are tasks still in high demand by the scientific community. Moreover, stopping power data are prerequisites in several applications in modern science, such as engineering, ion implantation and modification of materials, damage to electronics devices (e.g. space radiation), medical physics (e.g. proton therapy), among others. In this thesis we i) develop a rigorous experimental protocol to measure stopping power with high precision, and ii) investigate the collapse of the free electron gas (FEG) model in energy loss of light ions (protons) at a low energy range in transition and rare-earth metals. In the first part, we present an approach to obtain, with high accuracy, the stopping cross sections in the pure materials Al and Mo for protons in the energy range of [0.9 - 3.6] MeV by means of the transmission method. The traceability of the sources of uncertainties are fully evaluated and the final accuracy of the results is 0.63% (0.32% rand. and 0.54% syst.) for Al, and 1.5 % (0.44 % rand. and 1.4% syst.) for Mo, with both results primarily limited by the quality and homogeneity of the stopping foils. For Al, this high accuracy represents an improvement compared to the results obtained in previous studies and serves as a benchmark for our procedure. The most important sources of uncertainties were random - the uncertainty in the peak positions and in the Gaussian fits; and systematic - the non-uniformity thickness of the foils (a special procedure was developed to correct this). Even though the final uncertainty for Mo is higher than for Al, our results improve on the amount of data currently available for the energy range considered. Both data sets are compared with the most commonly employed theoretical models and Monte Carlo codes in the literature. In the second part, electronic stopping cross sections of nontrivial solids, that is, transition and rare earth metals (Ta and Gd) for slow protons are experimentally investigated, and the data were compared with the results for Pt and Au, to understand how energy losses in these metals are correlated with electronic band structures, and to understand the failure of the FEG model predictions. The higher stopping powers found for Ta and Gd cannot be explained by means of the FEG model; however, these effects are successfully correlated with the high density of states (DOS) of both the occupied and unoccupied electronic levels in these metals. For the case of Gd, the experimental data are extended in the energy range until the Bragg\'s peak is reached. The two parts of this thesis were published in Physical Review A 93 022704 (2016), and in Physical Review Letters 18 103401 (2017), respectively.O fenômeno de perda de energia quando um íon interage com a matéria, também conhecido como poder de freamento, vem sendo investigado por mais de um século, gerando grandes descobertas. Entretanto, conseguir obter medidas experimentais com alta precisão, ou elaborar um completo entendimento teórico dos processos de perda de energia são tarefas extremamente difíceis e ainda muito requeridas pela comunidade científica. Além disso, dados de perda de energia são pré-requisitos em várias aplicações e ramos da ciência moderna, tais como: engenharia, implantação e modificação de materiais, danos em dispositivos eletrônicos (radiação espacial), física médica (próton terapia), etc. Esta tese tem dois focos: i) desenvolver um rigoroso protocolo experimental para medir stopping power com alta precisão e ii) investigar a quebra de validade do modelo de Gás de Elétrons Livres (FEG) para a perda de energia de prótons lentos em metais de transição e terra raras. Na primeira parte apresentamos uma abordagem experimental para obter com alta precisão o poder de freamento em materiais puros (Al e Mo) para prótons no intervalo de energia de [0,9 - 3,6] MeV pelo método de transmissão. A rastreabilidade das fontes de incerteza foi determinada e as incertezas finais encontradas foram: 0,63 % (0,32 % aleat. e 0,54 % sist.) para Al e 1,5 % (0,44 % aleat. e 1,4 % sist.) para Mo, ambas devido a qualidade e homogeneidade das folhas freadoras. Para Al, esta acurácia representa um avanço comparado com publicações anteriores e, assim, serviu como uma referência de nosso procedimento. As mais importantes fontes de incerteza foram: aleatória incerteza das posições dos picos e dos ajustes Gaussianos e sistemática não-uniformidade das folhas-alvo (um procedimento foi desenvolvido para corrigir isso). Embora a incerteza final do Mo é um pouco maior do que do Al, nossos resultados ajudaram a complementar a baixa quantidade de dados disponíveis para o intervalo de energia considerado. Ambos conjuntos de dados foram comparados com os mais comuns modelos teóricos e códigos de Monte Carlo na literatura. Para a segunda parte, poder de freamento em metais não tão comuns tais como transição (Ta) e terras-raras (Gd) para prótons com baixas velocidades foram experimentalmente investigados, e os dados comparados com resultados de Pt e Au, a fim de entender como o stopping power destes metais está correlacionado com as estruturas de bandas eletrônicas, e assim tentar explicar a falha do modelo de FEG. Os altos valores das perdas de energias encontradas para Ta e Gd não puderam ser explicadas pelo modelo de FEG, e portanto foram correlacionados com a densidade de estados (DOS) em ambos os níveis ocupados e não ocupados destes metais. Para o caso do Gd, os dados experimentais foram estendidos em um intervalo de energia até alcançarem o pico de Bragg. A primeira parte desta tese foi publicada na Physical Review A 93 022704 (2016), e a segunda parte na Physical Review Letters 18 103401 (2017)

Study of boron quantification using ion beam analysis techniques.

Neste trabalho, estudamos e aplicamos técnicas analíticas com feixes iônicos para a identificação e quantificação do elemento químico Boro em amostras de Boro depositado sobre Níquel 11B/Ni, sobre Silício B/Si e em amostras de Silício Grau Metalúrgico - SiGM. Estas últimas foram fornecidas pelo grupo de metalurgia do Instituto de Pesquisas Tecnológicas (IPT). Especificamente, as seguintes técnicas analíticas foram utilizadas: Nuclear Reaction Analysis - NRA, Elastic Recoil Detection Analysis - ERDA e Secondary Ion Mass Spectrometry - SIMS. Nas amostras de B/Ni e B/Si, as concentrações foram obtidas com medidas de NRA, ERDA e SIMS. Também foi abordado quais dentre essas três técnicas apresentam menor limite de deteção e menor incerteza para a quantificação de Boro. Usando a reação nuclear 11B(p,a0)8Be, foi possível calcular a sua seção de choque diferencial para ângulo de espalhamento theta=170, cujo resultado, para este ângulo específico, é inédito na literatura. As amostras de SiGM foram analisadas com a técnica SIMS e comparadas com medidas de Inductively Coupled Plasma - ICP realizadas pelo grupo do IPT. Uma vez que técnicas nucleares podem ser consideradas absolutas, concluímos que as medidas de ICP apresentaram dados compatíveis com as medidas SIMS, e que o grupo de metalurgia do IPT está medindo as concentrações de Boro em suas amostras de SiGM corretamente por meio de ICP. Uma reta de calibração entre medidas SIMSxICP foi construída, que poderá servir como um guia para futuras quantificações de Boro com ICP feitas pelo grupo de metalurgia do IPT.In this work we investigated the use of analytical techniques based on ion beams in the quantification of Boron in many kinds of samples. Specifically, we applied techniques such Nuclear Reaction Analysis (NRA), Elastic Recoil Detection Analysis (ERDA) and Secondary Ion Mass Spectrometry (SIMS) to 11B/Ni and B/Si samples to measure the boron concentration. We also discuss and show what technique has a better detection limit and lower uncertainty. For the first time in the literature, we obtained the cross section for the $^{11}B(p,\\alpha_0){^8}Be$ nuclear reaction in the energy range from 1.6 up to 2.0 MeV in theta = 170 scattering angle. The SIMS technique was applied to analise samples of metallurgical grade silicon (SiGM) from Metallurgy Group of Instituto de Pesquisas Tecnologicas (IPT) to check the Inductively Coupled Plasma (ICP) measurements carried out by the IPT. Moreover, it was possible to build a calibration curve between SIMS and ICP measurements, that can be used to help of Metallurgy Group with futures ICP\'s measurements

Assessing electronic energy loss of heavy ions detected in reflection geometry

We study energy loss spectra of bromine ions scattered from silver thin films in the range of 4 to 36 MeV in forward reflection geometry. The different contributions to the energy loss were analyzed by complementary Monte-Carlo simulations. We assess the dependence of the scattering yield as well as nuclear and electronic losses on the penetration depth of detected ions. To investigate the entanglement of energy loss and depth information, electronic stopping cross sections were deduced from the experimental spectra by two different approaches: a) assuming a single scattering model and b) making use of Monte-Carlo simulations. The data obtained from the two approaches are compared and we assess the relative contributions from nuclear stopping as well as from the effect of multiple scattering on trajectory length. Results of both methods are compared to data from literature, to SRIM predictions and discussed in the context of composition depth‑profiling

Inventory of the ribbon worms (Phylum Nemertea) of Faial and Pico Islands, Azores.

A total of 9 nemertean species is recorded for the first time from Azorean waters. From a total of 38 individuals, 30 are identified as belonging to 9 different species whereas 8 individuals, which may be either local variants of known species or undescribed forms, are assigned to the Hoplo- or Palaeonemertea. The collection will contribute to part of a molecular phylogenetic study of the genus Tetrastemma

High sensitivity boron quantification in bulk silicon using the 11B(p,α0)8Be nuclear reaction.

There is a great need to quantify sub-ppm levels of boron in bulk silicon. There are several methods to analyze B in Si: Nuclear Reaction Analysis using the 11B(p, αₒ)8 Be reaction exhibits a quantification limit of some hundreds ppm of B in Si. Heavy Ion Elastic Recoil Detection Analysis offers a detection limit of 5 to 10 at. ppm. Secondary Ion Mass Spectrometry is the method of choice of the semiconductor industry for the analysis of B in Si. This work verifies the use of NRA to quantify B in Si, and the corresponding detection limits. Proton beam with 1.6 up to 2.6 MeV was used to obtain the cross-section of the 11B(p, αₒ)8 Be nuclear reaction at 170° scattering angle. The results show good agreement with literature indicating that the quantification of boron in silicon can be achieved at 100ppm level (high sensitivity) at LAMFI-IFUSP with about 16% uncertainty. Increasing the detection solid angle and the collected beam charge, can reduce the detection limit to less than 100 ppm meeting present technological needs.CNPqCAPE

Núcleos de Ensino da Unesp: artigos 2007

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq