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The large crescents imaged by ALMA in transition disks suggest that azimuthal dust trapping concentrates the larger grains, but centimetre-wavelengths continuum observations are required to map the distribution of the largest observable grains. A previous detection at ~1cm of an unresolved clump along the outer ring of MWC758 (Clump1), and buried inside more extended sub-mm continuum, motivates followup VLA observations. Deep multiconfiguration integrations reveal the morphology of Clump 1 and additional cm-wave components which we characterize via comparison with a deconvolution of recent 342GHz data (~1mm). Clump1, which concentrates ~1/3 of the whole disk flux density at ~1cm, is resolved as a narrow arc with a deprojected aspect ratio Chi>5.6, and with half the azimuthal width than at 342 GHz. The spectral trends in the morphology of Clump1 are quantitatively consistent with the Lyra-Lin prescriptions for dust trapping in an anticyclonic vortex, provided with porous grains (f~0.2+-0.2) in a very elongated (Chi~14+-3) and cold (T~23+-2K) vortex. The same prescriptions constrain the turbulence parameter alpha and the gas surface density Sigma_g through log10( alpha x Sigma_g /g/cm2)~-2.3+-0.4, thus requiring values for Sigma_g larger than a factor of a few compared to that reported in the literature from the CO isotopologues, if alpha, Comment: accepted to MNRAS

Michael Peel, Matias Vidal, Clive Dickinson and Paddy Leahy explain the discoveries underlying this stunning new map from the Planck Collaboration.

Anomalous Microwave Emission (AME) is a component of diffuse Galactic radiation observed at frequencies in the range $\approx 10$-60 GHz. AME was first detected in 1996 and recognised as an additional component of emission in 1997. Since then, AME has been observed by a range of experiments and in a variety of environments. AME is spatially correlated with far-IR thermal dust emission but cannot be explained by synchrotron or free-free emission mechanisms, and is far in excess of the emission contributed by thermal dust emission with the power-law opacity consistent with the observed emission at sub-mm wavelengths. Polarization observations have shown that AME is very weakly polarized ($\lesssim 1$%). The most natural explanation for AME is rotational emission from ultra-small dust grains ("spinning dust"), first postulated in 1957. Magnetic dipole radiation from thermal fluctuations in the magnetization of magnetic grain materials may also be contributing to the AME, particularly at higher frequencies ($\gtrsim 50$ GHz). AME is also an important foreground for Cosmic Microwave Background analyses. This paper presents a review and the current state-of-play in AME research, which was discussed in an AME workshop held at ESTEC, The Netherlands, June 2016., Comment: Accepted for publication in New Astronomy Reviews. Summary of AME workshop held at ESTEC, The Netherlands, June 2016, 40 pages, 18 figures. Updated to approximately match published version

There are several routes employed for the production of synthetic magnesium tetraborate, for example, sol–gel method, combustion, wet reaction synthesis, solid-state route and precipitation (crystal growth). The most commonly used synthesis methods are the wet reaction (precipitation) and solid-state synthesis; both production routes are efficient, but is very difficult to find a direct comparison for them. The present work proposes a direct comparison of both production routes used for magnesium tetraborate synthesis for thermoluminescent (TL) dosimetry. In this work, MgB4O7:Dy was prepared by both methods, wet reaction or precipitation-route 1, and solid-state synthesis -route 2, with the same amount of dopant (0.1%). In the first part of work, the crystalline phases were confirmed by X-ray diffraction (XRD) and it was observed that MgB4O7:Dy can be obtained satisfactorily through both routes, although a very intense crystalline phase of H3BO3 for the powder produced through route 1 was observed. The dose response curve of MgB4O7 pellets (produced for both routes) presents linear behavior when the materials are irradiated with 60Co in the dose range of 10–100 Gy. The results showed that both methods produce MgB4O7:Dy efficiently; however, solid-state synthesis produces MgB4O7:Dy more sensitive to gamma radiation.

This paper presents a model for the characterization and selection of beeswaxes for use as base substitute tissue for the manufacture of objects suitable for external radiotherapy using megavoltage photon beams. The model of characterization was divided into three distinct stages: 1) verification of aspects related to the origin of the beeswax, the bee species, the flora in the vicinity of the beehives and procedures to detect adulterations; 2) evaluation of physical and chemical properties; and 3) evaluation of beam attenuation capacity. The chemical composition of the beeswax evaluated in this study was similar to other simulators commonly used in radiotherapy. The behavior of the mass attenuation coefficient in the radiotherapy energy range was comparable to other simulators. The proposed model is efficient and enables convenient assessment of the use of any particular beeswax as a base substitute tissue for radiotherapy.

Anomalous Microwave Emission (AME) has been previously studied in two well-known molecular clouds and is thought to be due to electric dipole radiation from small spinning dust grains. It is important to measure the polarization properties of this radiation both for component separation in future cosmic microwave background experiments and also to constrain dust models. We have searched for linearly polarized radio emission associated with the $\rho$ Ophiuchi and Perseus molecular clouds using {\it WMAP} 7-year data. We found no significant polarization within an aperture of $2^{\circ}$ diameter. The upper limits on the fractional polarization of spinning dust in the $\rho$ Ophiuchi cloud are 1.7%, 1.6% and 2.6% (at 95% confidence level) at K-, Ka- and Q-bands, respectively. In the Perseus cloud we derived upper limits of 1.4%, 1.9% and 4.7%, at K-, Ka- and Q-bands, respectively; these are similar to those found by L\'opez-Caraballo et al. If AME at high Galactic latitudes has a similarly low level of polarization, this will simplify component separation for CMB polarization measurements. We can also rule out single domain magnetic dipole radiation as the dominant emission mechanism for the 20-40 GHz. The polarization levels are consistent with spinning dust models.

An anomalous radio continuum component at cm-wavelengths has been observed in various sources, including dark clouds. This continuum component represents a new property of the ISM. In this work we focus on one particular dark cloud, the bright reflection nebula M 78. The main goal of this work is to invetigate cm-wave continuum emission in a prominent molecular cloud, nearby and with complementary observational data. We acquired Cosmic Background Imager (CBI) visibility data of M 78 at 31 GHz with an angular resolution of $\sim 5.8\arcmin$ and CBI2 data at an angular resolution of $\sim 4.2\arcmin$. A morphological analysis was undertaken to search for possible correlations with templates that trace different emission mechanisms. Using data from WMAP and the Rhodes/HartRAO 2326 MHz survey we constructed the spectral energy distribution (SED) of M 78 in a $45\arcmin$ circular aperture. We used results from the literature to constrain the physical conditions and the stellar content. The 5 GHz -- 31 GHz spectral index in flux density ($\alpha = 1.89\pm 0.15$) is significantly different from optically thin free-free values. We also find closer morphological agreement with IR dust tracers than with free-free sources. Dust-correlated cm-wave emission that is not due to free-free is significant at small scales ($\sim 8\arcmin$). However, a free-free background dominates at cm-wavelengths on large scales ($\sim 1$ deg). We correct for this uniform background by differencing against a set of reference fields. The differenced SED of M 78 shows excess emission at 10-70 GHz over free-free and a modified blackbody, at $3.4\sigma$. The excess is matched by the spinning dust model from Draine and Lazarian (1998).

Considering the difficulties related to determination the dose delivered on the bladder during procedures of gynecological brachytherapy of high dose rate, this study presents a prototype of a dynamic simulator (phantom) suitable for experimental dosimetry of these organs during this type of procedure. In order to evaluate the phantom´s ability to simulate real clinical situations, a dosimetric study was conducted using radiochromic film and optically stimulated luminescence dosimeters (OSLDs). The phantom was constructed of polymethyl methacrylate (PMMA) and ácido polilático (PLA). Artificial bladders were printed in three dimensions, from computed tomography images (CT) of real patients with brachytherapy applicators already positioned. In the phantom, the artificial bladder can move in all directions. The films and OSLDs were placed on the artificial bladder walls and the applicators were placed according to the original CT image. The prototype phantom simulated the behavior of dose on the surface of each printed bladder. The dosimetric study showed agreement in most cases, with the results obtained from a computerized planning system. In this sense, the methodology presented in this study provides conditions for experimental investigations on the behavior of dose on the surface of the bladder due procedures of intracavitary brachytherapy of cervix. Considerando as dificuldades relacionadas à determinação da dose experimentada pela bexiga urinária durante procedimentos de braquiterapia ginecológica de alta taxa de dose, este estudo apresenta um protótipo de um objeto simulador dinâmico (fantoma) apropriado para dosimetria experimental desse órgão nesses tipos de procedimentos. Com o intuito de avaliar a capacidade do fantoma em simular situações clínicas reais, um estudo dosimétrico foi realizado utilizando filme radiocrômico e dosímetros de luminescência opticamente estimulada (OSLDs). O fantoma foi construído de polimetilmetacrilato (PMMA) e ácido polilático (PLA). Bexigas artificiais foram impressas em três dimensões,a partir de imagens de tomografia computadorizada (TC) de pacientes reais com os aplicadores braquiterápicos já posicionados. No fantoma, após o posicionamento, uma bexiga artificial pode se mover em todas as direções. Os filmes e os OSLDs foram posicionados nas paredes das bexigas artificiais, e os aplicadores foram colocados de acordo com a imagem original TC. O fantoma protótipo simulou o comportamento da dose na superfície de cada bexiga impressa. Os estudos dosimétricos exibiram concordância, na maioria dos casos, com os resultados obtidos a partir de um sistema de planejamento computadorizado. Nesse sentido, a metodologia apresentada nesse estudo oferece condições para investigações experimentais sobre o comportamento da dose na superfície da bexiga devido procedimentos de braquiterapia intracavitária de colo do útero.

Objetivo: Avaliar a situação atual da braquiterapia de alta taxa dose (BATD) realizada no Brasil para neoplasias do colo uterino, no que diz respeito aos aparelhos, métodos de planejamento, prescrições, fracionamentos e avaliações de dose nos órgãos de risco. Materiais e Métodos: Foi elaborado um questionário contendo questões de múltipla escolha, o qual, entre os meses de março de 2012 e maio de 2013, foi enviado a 89 instituições hospitalares de todo o Brasil que possuem equipamento de BATD. Resultados: Sessenta e um serviços responderam o questionário. Todas as regiões do País experimentaram aumento acentuado no número de serviços que oferecem BATD entre os anos de 2001 e 2013. Quanto aos planejamentos, apesar de 91% dos centros afirmarem que possuem softwares capazes de suportar planejamento tridimensional, o aparelho de raios X convencional foi apontado por 92% dos entrevistados como ferramenta de aquisição de imagens na rotina. Aproximadamente 35% dos entrevistados afirmaram que as sessões de braquiterapia são realizadas após a teleterapia. O esquema de quatro inserções de 7 Gy foi apontado como o mais praticado. Conclusão: Neste estudo percebeu-se que há dificuldade dos profissionais ao acesso às ferramentas de aquisição de imagens adjuvantes aos planejamentos tridimensionais, como tomografia computadorizada e ressonância magnética. Objective: To assess the current situation of high-dose-rate (HDR) brachytherapy for cancer of the cervix in Brazil, regarding apparatuses, planning methods, prescription, fractionation schedule and evaluation of dose in organs at risk. Materials and Methods: In the period between March/2012 and May/2013, a multiple choice questionnaire was developed and sent to 89 Brazilian hospitals which perform HDR brachytherapy. Results: Sixty-one services answered the questionnaire. All regions of the country experienced a sharp increase in the number of HDR brachytherapy services in the period from 2001 to 2013. As regards planning, although a three-dimensional planning software was available in 91% of the centers, conventional radiography was mentioned by 92% of the respondents as their routine imaging method for such a purpose. Approximately 35% of respondents said that brachytherapy sessions are performed after teletherapy. The scheme of four 7 Gy intracavitary insertions was mentioned as the most frequently practiced. Conclusion: The authors observed that professionals have difficulty accessing adjuvant three-dimensional planning tools such as computed tomography and magnetic resonance imaging.

Contamination of well water in a rural area and of spring water in an urban area by effect of animal slurry management and storage practices, and the municipal water supply network were studied. For this purpose, a number of factors including electrical conductivity, dry residue, pH, dissolved oxygen, nitrate, nitrite, ammonium, organic matter, turbidity, colour, iron, manganese, copper and zinc were examined. Data were subjected to multivariate principal component analysis and cluster analysis. The statistical interpretation of the results allowed two principal factors (F1 and F2) to be assigned to saline and organometallic contamination, respectively, of the water. The axes of the plots of factor loadings represent the overall water concentration-dilution effect (F1) and oxidoreduction (F2), respectively. The spatial distribution of the samples is dictated by the prevailing type of contamination. In temporal terms, however, samples cluster by date in urban springs and by contamination type in rural wells. © 2000 Academic Press.

Polarisation amplitude estimation is affected by a positive noise bias, particularly important in regions with low signal-to-noise ratio (SNR). We present a new approach to correct for this bias in the case there is additional information about the polarisation angle. We develop the 'known-angle estimator' that works in the special case when there is an independent and high signal-to-noise ratio ($\gtrsim 2\sigma$) measurement of the polarisation angle. It is derived for the general case where the uncertainties in the Q,U Stokes parameters are not symmetric. This estimator completely corrects for the polarisation bias if the polarisation angle is perfectly known. In the realistic case, where the angle template has uncertainties, a small residual bias remains, but that is shown to be much smaller that the one left by other classical estimators. We also test our method with more realistic data, using the noise properties of the three lower frequency maps of WMAP. In this case, the known-angle estimator also produces better results than methods that do not include the angle information. This estimator is therefore useful in the case where the polarisation angle is expected to be constant over different data sets with different SNR., Comment: 9 pages. Accepted by MNRAS

To assess the current situation of high-dose-rate (HDR) brachytherapy for cancer of the cervix in Brazil, regarding apparatuses, planning methods, prescription, fractionation schedule and evaluation of dose in organs at risk.In the period between March/2012 and May/2013, a multiple choice questionnaire was developed and sent to 89 Brazilian hospitals which perform HDR brachytherapy.Sixty-one services answered the questionnaire. All regions of the country experienced a sharp increase in the number of HDR brachytherapy services in the period from 2001 to 2013. As regards planning, although a three-dimensional planning software was available in 91% of the centers, conventional radiography was mentioned by 92% of the respondents as their routine imaging method for such a purpose. Approximately 35% of respondents said that brachytherapy sessions are performed after teletherapy. The scheme of four 7 Gy intracavitary insertions was mentioned as the most frequently practiced.The authors observed that professionals have difficulty accessing adjuvant three-dimensional planning tools such as computed tomography and magnetic resonance imaging.Avaliar a situação atual da braquiterapia de alta taxa dose (BATD) realizada no Brasil para neoplasias do colo uterino, no que diz respeito aos aparelhos, métodos de planejamento, prescrições, fracionamentos e avaliações de dose nos órgãos de risco.Foi elaborado um questionário contendo questões de múltipla escolha, o qual, entre os meses de março de 2012 e maio de 2013, foi enviado a 89 instituições hospitalares de todo o Brasil que possuem equipamento de BATD.Sessenta e um serviços responderam o questionário. Todas as regiões do País experimentaram aumento acentuado no número de serviços que oferecem BATD entre os anos de 2001 e 2013. Quanto aos planejamentos, apesar de 91% dos centros afirmarem que possuemNeste estudo percebeu-se que há dificuldade dos profissionais ao acesso às ferramentas de aquisição de imagens adjuvantes aos planejamentos tridimensionais, como tomografia computadorizada e ressonância magnética.

The RDS-peripherin gene encodes a photoreceptor-specific protein that is localized in the outer segment disc membranes of both rods and cones. We screened a Spanish family with central areolar choroidal dystrophy for mutations in candidate genes. A base substitution was identified in the RDS-peripherin gene of one patient and DNA sequencing revealed a C-to-T transition in codon 172, arginine being substituted by tryptophan. The mutation was also detected in two asymptomatic family members who showed irregular pigmentation in the retinal pigment epithelium (RPE). The phenotype is similar to other macular dystrophies caused by mutation in the RDS-peripherin gene.

Nowadays the industry requires higher operational efficiency and reservoir management optimization. It is essencial for making decisions to have information in a timely and integral manner. The objective of this report is to demonstrate how the use of surveillance together with specific well management software came to be an important tool to take more accurate and faster decisions. It provides access to real time events and data, and also makes it easier to have an efficient and cooperative interaction between people in different areas, optimizing the task flow. This research describes the hardware and software components of the surveillance system and analyzes how the different modules of the management software work. The results show how minimizing downtime through early events detection increased production and how the efficient use of resources reduced the lifting cost. This all translates to a better operational organization and makes it possible to act proactively by identifying potential problems or failures in wells. In conclusion, having a digitalized oil field allows us to reach agreement easily and to concentrate efforts in solving problems, through the close relationship that is achieved between technology, processes and people. This technology has a broad application range because it integrates the different operational levels while minimizing financial risks. The use of this technology can be leveraged to most of the current artificial lift systems and it is compatible with many of the drivers/interfaces available in the market. This helps to reinforce in Argentina the incorporation of technology as a management tool for the exploitation of oil fields. It can boost corporate social responsibility, by having a significant impact on profits with the available resources and integrating the organization towards operational excellence.

We conducted the first study to examine rates of sexual activity, sexual risk behaviors, sexual protective behaviors, injection drug use (IDU), needle sharing, and knowledge about HIV/AIDS among outpatients with severe mental illness (SMI) in Rio de Janeiro, Brazil. Using a measure with demonstrated reliability, we found that 42% of 98 patients engaged in vaginal or anal sex within the past three months. Comorbid substance use disorder was significantly associated with sexual activity. Only 22% of sexually active patients used condoms consistently, despite having better HIV knowledge than those who were sexually abstinent. Overall, 45% of patients reported not engaging in any HIV protective behaviors. There were no reports of drug injection. Adults with SMI in Brazil are in need of efficacious HIV prevention programs and policies that can sustain these programs within mental health treatment settings.

We investigated the effects of slurry application on water quality in wells, pasture-drainage conduits and rivers. The parameters determined were electrical conductivity, dry residue, pH, dissolved O2 ,N O ˇ ,N O ˇ ,C l ˇ , Na, PO 3ˇ 4 organic matter content, COD, suspended solids, turbidity, colour, Fe, Mn, Cu and Zn. The data were analysed by principal components analysis and cluster analysis. The first axis extracted by principal components analysis of the samples-by-variables matrix represented the degree of dilution of the water strongly related with saline content; the second axis represented redox conditions, affecting organometallic component. In general, the positions of the samples in this factor space reflected the major contamination processes affecting water resources of that type (wells, conduits or rivers). In the case of river-water samples, cluster analysis showed that month of sampling had a clear effect, reflecting the importance of rainfall. Finally, in all three water resource types, contamination was most severe in the area of highest livestock density and highest frequency of slurry application. # 2000 Elsevier Science B.V. All rights reserved.

In this chapter, we will outline the scientific motivation for studying Anomalous Microwave Emission (AME) with the SKA. AME is thought to be due to electric dipole radiation from small spinning dust grains, although thermal fluctuations of magnetic dust grains may also contribute. Studies of this mysterious component would shed light on the emission mechanism, which then opens up a new window onto the interstellar medium (ISM). AME is emitted mostly in the frequency range $\sim 10$--100\,GHz, and thus the SKA has the potential of measuring the low frequency side of the AME spectrum, particularly in band 5. Science targets include dense molecular clouds in the Milky Way, as well as extragalactic sources. We also discuss the possibility of detecting rotational line emission from Poly-cyclic Aromatic Hydrocarbons (PAHs), which could be the main carriers of AME. Detecting PAH lines of a given spacing would allow for a definitive identification of specific PAH species., Comment: 11 pages, 4 pages, to be published in Proceedings of Science: "Advancing Astrophysics with the Square Kilometre Array"

Cosmic rays (CRs) interact with the gas, the radiation field and the magnetic field in the Milky Way, producing diffuse emission from radio to gamma rays. Observations of this diffuse emission and comparison with detailed predictions are powerful tools to unveil the CR properties and to study CR propagation. We present various GALPROP CR propagation scenarios based on current CR measurements. The predicted synchrotron emission is compared to radio surveys, and synchrotron temperature maps from WMAP and Planck, while the predicted interstellar gamma-ray emission is compared to Fermi-LAT observations. We show how multi-wavelength observations of the Galactic diffuse emission can be used to help constrain the CR lepton spectrum and propagation. Finally we discuss how radio and microwave data could be used in understanding the diffuse Galactic gamma-ray emission observed with Fermi-LAT, especially at low energies., 8 pages, 5 figures; in Proceedings of the 34th International Cosmic Ray Conference (ICRC 2015), The Hague (The Netherlands); Oral contribution

We used data from the \wmap satellite at 23, 33 and 41 GHz to study the diffuse polarised emission over the entire sky. The emission originates mostly from filamentary structures with well-ordered magnetic fields. Some of these structures have been known for decades in radio continuum maps. Their origin is not clear and there are many filaments that are visible for the first time. We have identified and studied 11 filaments. The polarisation fraction of some of them can be as high as 40\%, which is a signature of a well ordered magnetic field. The polarisation spectral indices, averaged over 18 regions in the sky is $\beta = -3.06 \pm 0.02$, consistent with synchrotron radiation. There are significant variations in $\beta$ over the sky ($\Delta\beta\approx0.2$). We explore the link between the large-scale filaments and the local ISM, using the model of an expanding shell in the solar vicinity. We compared observed polarisation angles with the predictions from the model and found good agreement. This strongly suggests that many large scale filaments and loops are nearby structures. This is important in the context of the Galactic magnetic field as these structures are normally included in global models, neglecting the fact that they might be local. We also studied the level of contamination added by the diffuse filaments to the CMB polarisation power spectra. We conclude that, even though these filaments present low radio brightness, a careful removal will be necessary for future all-sky CMB polarisation analysis., Comment: 21 pages. 17 Figures. Accepted in MNRAS

Submitted by Boris Flegr (boris@uerj.br) on 2021-01-06T20:50:36Z No. of bitstreams: 1 Fabia Shirley Pereira Vasconcelos Dissertacao completa.pdf: 1682700 bytes, checksum: 402a495cf20baab737981ca395b80277 (MD5) Made available in DSpace on 2021-01-06T20:50:36Z (GMT). No. of bitstreams: 1 Fabia Shirley Pereira Vasconcelos Dissertacao completa.pdf: 1682700 bytes, checksum: 402a495cf20baab737981ca395b80277 (MD5) Previous issue date: 2018-06-04 Ministério da Saúde The objective of this work is to evaluate dosimetrically with radiocromic films the results obtained in the calculation of the dose with the Eclipse Planning System, using AAA (Anisotropic Analytical-Algorithm of Varian) and Acuros (AXB) calculation algorithms at specific points arranged strategically in different interfaces between media of different densities. To this end, twelve plannings were carried out, of which six use the tool for the correction of heterogeneity for the medium and six do not use this correction. A simulator composed of layers of solid water and cork was used as phantom during the steps that involve the dose delivery process when calculated by TPS based on tomography. And for the use of the EBT3 film, the steps of preparation and calibration, which enable its use as dosimeter, have been fulfilled. As a result, differences between the planned dose distribution and the measured dose up to minus 9% were obtained for the calculated dose without correction of the media heterogeneity. The present study concluded that the non-correction of heterogeneity results in doses distributions underestimated by the calculation algorithms, thus jeopardizing the therapeutic quality of radiotherapy. Therefore, the importance of using the correction of heterogeneity in TPS is ratified O objetivo deste trabalho é avaliar dosimetricamente com filmes radiocrômicos os resultados obtidos no cálculo da dose com o Sistema de Planejamento Eclipse , utilizando os algoritmos de cálculo AAA (Anisotropic Analytical-Algorithm da Varian) e Acuros (AXB), em pontos específicos, dispostos estrategicamente, em diferentes interfaces entre meios de diferentes densidades. Com essa finalidade, foram realizados doze planejamentos, seis deles utilizando a ferramenta de correção da heterogeneidade para o meio e seis sem essa correção. Um simulador composto por camadas de água sólida e de cortiça foi utilizado como fantoma durante as etapas que envolvem o processo de entrega da dose quando calculada pelo TPS baseado em tomografia. E para a utilização do filme EBT3, foram cumpridas as etapas de preparação e calibração do mesmo, que habilita a sua utilização como dosímetro. Como resultados foram obtidas diferenças entre a distribuição da dose planejada e a dose medida de até - 9% para a dose calculada sem a correção da heterogeneidade do meio. Para as condições de estudo utilizadas, observamos que a não correção da heterogeneidade pode resultar em distribuições de doses subestimadas pelos algoritmos de cálculo, comprometendo, assim, a qualidade terapêutica da radioterapia. Portanto, ratifica-se a importância do uso da correção da heterogeneidade nos TPS

Submitted by Boris Flegr (boris@uerj.br) on 2021-01-06T20:50:42Z No. of bitstreams: 1 Camila Costa Ribeiro Dissertacao completa.pdf: 3193152 bytes, checksum: 8124c10e7b528f719b9a12997ca25d89 (MD5) Made available in DSpace on 2021-01-06T20:50:42Z (GMT). No. of bitstreams: 1 Camila Costa Ribeiro Dissertacao completa.pdf: 3193152 bytes, checksum: 8124c10e7b528f719b9a12997ca25d89 (MD5) Previous issue date: 2018-06-04 Ministério da Saúde The technique of treatment called brachytherapy is a modality of radiotherapy in which the application of the dose of ionizing radiation to the patient occurs from radionuclides that, in sealed sources, are placed directly in the tumor volume (target of the treatment) or very close to this volume. This paper deals with high-dose intracavitary brachytherapy with an Iridium-192 source, aimed at the treatment of gynecological tumors. There have been many technological advances in this area in recent years, and with them, advances in quality control techniques for this treatment modality are becoming increasingly necessary. In this way, the present work has the objective to meet this need, offering a proposal of evaluation of the treatment delivered in relation to what is planned. For this, the creation of a prototype that was made in polylactic acid (PLA) using a 3D printer (fast and low cost manufacturing technology). A fundamental part of the irradiation arrangement, the phantom acts as a support for the placement of 4 parts of radiochromic film, a dosimeter widely used in brachytherapy. The methodology presented in this paper sought to investigate the capacity of the remote afterloading system to execute the treatment plan as foreseen by the computerized planning system (TPS) A técnica de tratamento chamada braquiterapia é uma modalidade da radioterapia na qual a aplicação da dose de radiação ionizante no paciente ocorre a partir de radionuclídeos que, em fontes seladas, são colocadas diretamente no volume de tumor (alvo do tratamento) ou muito próximas a este volume. Este trabalho trata da braquiterapia intracavitária de alta taxa de dose com fonte de Irídio-192, voltada para tratamentos de tumores ginecológicos. Muitos foram os avanços tecnológicos ocorridos nesta área nos últimos anos e, com eles, se tornam cada vez mais necessários os avanços também nas técnicas de controle da qualidade para esta modalidade de tratamento. Deste modo, o presente trabalho tem o objetivo de atingir essa necessidade, oferecendo uma proposta de avaliação do tratamento entregue em relação ao planejado. Realizou-se, para isso, a criação de um protótipo que foi confeccionado em uma impressora 3D (tecnologia de fabricação rápida e de baixo custo) que consta de um fantoma impresso em ácido polilático (PLA). Peça fundamental no arranjo de irradiação, o fantoma desenvolvido neste trabalho funciona como um suporte para o posicionamento de 4 partes de filmes radiocrômicos, dosímetro largamente utilizado em braquiterapia. A metodologia apresentada neste trabalho buscou a investigação da capacidade do sistema remoto de carga postergada, o remote afterloading, em executar o plano de tratamento conforme previsto pelo sistema de planejamento computadorizado (TPS)