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1.
Environ Monit Assess ; 194(10): 722, 2022 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-36056971

RESUMO

A physiographic-based multilinear regression model supported by GIS was developed to estimate spatial rainfall variability in the Southwest Iberian Peninsula. The area study includes a wide diversity of landscape features and comprises four Portuguese regions and one Spanish province (totalizing 28,860 km2). The region suffers a very strong Mediterranean influence, with a major cleavage between winter and summer seasons. Thus, the analysis was carried out separately for the wet (October to March) and dry (April to September) semesters. From an initial set of 10 explanatory physiographic variables, five were selected to be used in the multilinear regression, as they allowed generating models by map algebra that fitted well with the last 40 years of monthly rainfall data records. These records were obtained from 163 weather stations, filtered from an initial set of 230 (142 stations in Portugal and 88 in Spain). The correlation between the physiographic-based multilinear regression model and a model obtained by interpolation from rainfall historical data showed to be good or very good in approximately 75% of the area under study. Results show that physiographic-based models can be effectively used to estimate rainfall where there is a lack of rain gauges, or to densify spatial resolution of rainfall between rain gauges.


Assuntos
Monitoramento Ambiental , Chuva , Estações do Ano , Espanha , Tempo (Meteorologia)
2.
Eur J Nucl Med Mol Imaging ; 44(13): 2169-2178, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28785842

RESUMO

PURPOSE: The purpose of our study was to test a new staging algorithm, combining clinical TNM staging (cTNM) with whole-body metabolic active tumor volume (MATV-WB), with the goal of improving prognostic ability and stratification power. METHODS: Initial staging [18F]FDG PET/CT of 278 non-small cell lung cancer (NSCLC) patients, performed between January/2011 and April/2016, 74(26.6%) women, 204(73.4%) men; aged 34-88 years (mean ± SD:66 ± 10), was retrospectively evaluated, and MATV-WB was quantified. Each patient's follow-up time was recorded: 0.7-83.6 months (mean ± SD:25.1 ± 20.3). RESULTS: MATV-WB was an independent and statistically-significant predictor of overall survival (p < 0.001). The overall survival predictive ability of MATV-WB (C index: mean ± SD = 0.7071 ± 0.0009) was not worse than cTNM (C index: mean ± SD = 0.7031 ± 0.007) (Z = -0.143, p = 0.773). Estimated mean survival times of 56.3 ± 3.0 (95%CI:50.40-62.23) and 21.7 ± 2.2 months (95%CI:17.34-25.98) (Log-Rank = 77.48, p < 0.001), one-year survival rate of 86.8% and of 52.8%, and five-year survival rate of 53.6% and no survivors, were determined, respectively, for patients with MATV-WB < 49.5 and MATV-WB ≥ 49.5. Patients with MATV-WB ≥ 49.5 had a mortality risk 2.9-5.8 times higher than those with MATV-WB < 49.5 (HR = 4.12, p < 0.001). MATV-WB cutoff points were also determined for each cTNM stage: 23.7(I), 49.5(II), 52(III), 48.8(IV) (p = 0.029, p = 0.227, p = 0.025 and p = 0.001, respectively). At stages I, III and IV there was a statistically-significant difference in the estimated mean overall survival time between groups of patients defined by the cutoff points (p = 0.007, p = 0.004 and p < 0.001, respectively). At stage II (p = 0.365), there was a clinically-significant difference of about 12 months between the groups. In all cTNM stages, patients with MATV-WB ≥ cutoff points had lower survival rates. Combined clinical TNM-PET staging (cTNM-P) was then tested: Stage I < 23.7; Stage I ≥ 23.7; Stage II < 49.5; Stage II ≥ 49.5; Stage III < 52; Stage III ≥ 52; Stage IV < 48.8; Stage IV ≥ 48.8. cTNM-P staging presented a superior overall survival predictive ability (C index = 0.730) compared with conventional cTNM staging (C index = 0.699) (Z = -4.49, p < 0.001). CONCLUSION: cTNM-P staging has superior prognostic value compared with conventional cTNM staging, and allows better stratification of NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/patologia , Fluordesoxiglucose F18 , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Carga Tumoral , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias
3.
Eng. sanit. ambient ; Eng. sanit. ambient;27(1): 169-173, jan.-fev. 2022. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1364814

RESUMO

ABSTRACT This work presented the development and testing of a large-scale rainfall simulator (LSRS) to be used as a research tool on rainfall-runoff and associated transport processes in urban areas. The rainfall simulator consists of a pressurized water supply system which supplies a set of 16 full-cone nozzles. Artificial rainfall with different rainfall intensities can be produced over an area of 100 m2 in a V shape. The assembly is housed in a tailor-made acrylic structure to eliminate the influence of wind and natural rainfall. Runoff is measured and collected at the outlet of the drainage basin, from where it is pumped to a storage tank that enables the reuse of water. Runoff hydrographs and pollutographs are presented as examples of possible outcomes from this facility. The LSRS is showed to be able to reproduce the rainfall-runoff and pollutant transport processes under simulated rainfall events with intensity and spatial uniformity similar to other experiments described in the literature.


RESUMO Este trabalho apresentou o desenvolvimento e teste de um simulador de chuva em larga escala (large-scale rainfall simulator — LSRS) para utilização em pesquisa sobre o processo de chuva-vazão e processos associados em áreas urbanas. O simulador é composto por um sistema pressurizado de abastecimento de água que abastece um conjunto de 16 bicos aspersores. Chuvas artificiais com diferentes intensidades de precipitação podem ser produzida sobre uma bacia de drenagem com área de 100.0 m2 em forma de V. O simulador é protegido por uma estrutura em acrílico que elimina a influência do vento e da chuva natural. A vazão é medida e coletada no exutório da bacia de drenagem, de onde é bombeada para um reservatório de armazenamento que permite a reutilização da água. Hidrogramas de vazão e polutogramas são apresentados como exemplos de possíveis resultados de ensaios a serem realizados com este equipamento. O LSRS demonstrou ser possível reproduzir o processo de chuva-vazão e processos associados sob eventos de chuva simulada com intensidade e distribuição espacial semelhantes a outros experimentos descritos na literatura.

4.
Phys Med ; 41: 93-96, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28487206

RESUMO

PURPOSE: The aim of this study is to compare two routine protocols at our institution, CTPA and V/P-SPECT, in terms of radiation dose to the most exposed organs (lungs and breast) and to the embryo/fetus in the case of pregnant patients. METHODS: At our institution, the CTPA protocol includes a contrast enhanced CT (scan parameters: 100kVp, 700mA, 0.5s/rot, pitch 0.984) and in some cases a non-contrast enhanced CT acquisition (120kVp, 400mA, 0.5s/rot, pitch 1.375). In the V/P-SPECT protocol, ventilation SPECT was performed after inhalation of 99mTc-Technegas, reaching 30MBq in the lungs; perfusion was performed after intravenous administration of 60-120MBq of 99mTc-MAA. The absorbed doses (mGy) to lungs and breast from CTPA were estimated using the "ImPACT CT Patient Dosimetry Calculator". The embryo/fetus dose was estimated for different gestational stages (0-7, 8-12, 13-25 and 26-40weeks) using the web based calculation tool "COnceptus Dose Estimation" (CODE). Doses to organs and embryo/fetus from V/P-SPECT were estimated based on published dose data normalized to administered activity (mGy/MBq). RESULTS: Embryo/fetus absorbed doses are similar for CTPA and V/P-SPECT and bellow 1mGy. The calculated dose to the lungs (breast) was 1.3-10.6 (27-136) times higher from CTPA when compared with V/P-SPECT. CONCLUSION: For the diagnosis of PE in women, if both imaging modalities are available, it is recommended to proceed with V/P-SPECT rather than CTPA due to the considerably lower radiation dose to the breast.


Assuntos
Angiografia por Tomografia Computadorizada , Embolia Pulmonar/diagnóstico por imagem , Doses de Radiação , Tomografia Computadorizada de Emissão de Fóton Único , Mama/efeitos da radiação , Feminino , Feto/efeitos da radiação , Humanos , Pulmão/efeitos da radiação , Órgãos em Risco , Gravidez
5.
Phys Med ; 32(1): 1-6, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26851162

RESUMO

This EFOMP Policy Statement is an update of Policy Statement No. 6 first published in 1994. The present version takes into account the European Union Parliament and Council Directive 2013/55/EU that amends Directive 2005/36/EU on the recognition of professional qualifications and the European Union Council Directive 2013/59/EURATOM laying down the basic safety standards for protection against the dangers arising from exposure to ionising radiation. The European Commission Radiation Protection Report No. 174, Guidelines on Medical Physics Expert and the EFOMP Policy Statement No. 12.1, Recommendations on Medical Physics Education and Training in Europe 2014, are also taken into consideration. The EFOMP National Member Organisations are encouraged to update their Medical Physics registration schemes where these exist or to develop registration schemes taking into account the present version of this EFOMP Policy Statement (Policy Statement No. 6.1"Recommended Guidelines on National Registration Schemes for Medical Physicists").


Assuntos
Física Médica/legislação & jurisprudência , Física Médica/organização & administração , Proteção Radiológica/legislação & jurisprudência , Exposição Ambiental , União Europeia , Guias como Assunto , Modelos Organizacionais , Exposição Ocupacional , Política Pública , Segurança
6.
Phys Med ; 32(1): 7-11, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26851163

RESUMO

Continuing Professional Development (CPD) is vital to the medical physics profession if it is to embrace the pace of change occurring in medical practice. As CPD is the planned acquisition of knowledge, experience and skills required for professional practice throughout one's working life it promotes excellence and protects the profession and public against incompetence. Furthermore, CPD is a recommended prerequisite of registration schemes (Caruana et al. 2014) and is implied in the Council Directive 2013/59/EURATOM (EU BSS) and the International Basic Safety Standards (BSS). It is to be noted that currently not all national registration schemes require CPD to maintain the registration status necessary to practise medical physics. Such schemes should consider adopting CPD as a prerequisite for renewing registration after a set period of time. This EFOMP Policy Statement, which is an amalgamation and an update of the EFOMP Policy Statements No. 8 and No. 10, presents guidelines for the establishment of national schemes for CPD and activities that should be considered for CPD.


Assuntos
Física Médica/educação , Física Médica/métodos , Currículo , Educação Médica Continuada , União Europeia , Guias como Assunto , Política Pública , Segurança
7.
Eng. sanit. ambient ; Eng. sanit. ambient;25(1): 97-106, jan.-fev. 2020. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1090125

RESUMO

RESUMO O estudo do escoamento superficial e transporte de poluentes é de grande importância, pois ajuda na prevenção de impactos ambientais, auxiliando em planejamentos a serem realizados pelo poder público. Neste trabalho, teve-se como objetivo estudar, em laboratório, a dinâmica do transporte de material (cloreto de sódio - NaCl) disposto sobre uma superfície impermeável, dissolvido pela aplicação de água via simulador de chuva, tendo como fonte de variação três variáveis independentes: declividade, intensidade de precipitação e posição do material. Utilizou-se o delineamento experimental de faces centradas, que contemplou diferentes cenários reproduzidos nos experimentos, onde se avaliou a influência das três variáveis independentes sobre às dependentes (tempo de transporte, valor de pico, tempo de pico e massa total transportada), cujas respostas foram monitoradas no exutório do modelo experimental. A análise de resultados obtidos permitiu identificar o efeito significativo da declividade e posição do material sobre todas as variáveis dependentes estudadas e ainda o efeito quadrático da declividade para o tempo de transporte e a massa total transportada. Já para a intensidade de precipitação, verificou-se influência apenas para o tempo de transporte, dentro dos intervalos de estudo com nível de significância de 95%. O modelo produzido para o tempo de transporte é capaz de explicar 90% da variabilidade dos dados, enquanto o para o valor de pico possui uma capacidade de explicação de 67,9%. O tempo de pico possui um modelo capaz de explicar 74,2% da variabilidade dos dados, e o modelo produzido para a massa total transportada possui uma capacidade de explicação de 62,4% da variabilidade dos dados.


ABSTRACT The study of surface runoff and transport of pollutants is of major importance, as it helps preventing environmental impacts, and supports planning tasks carried out by public authorities. The goal of this research was to study the dynamics of the transport of material (NaCl) on an impermeable surface, dissolved by the application of water through a rainfall simulator, having as its source of variation three independent variables: slope, rainfall intensity and position of the material. Face-centered experimental design was used, which contemplated different scenarios reproduced in the experiments, where the influence of the three independent variables on the dependent variables (transport time, peak value, peak time and total mass transported) was evaluated, whose responses were monitored at the outlet of the experimental model. The analysis of the results allowed to identify the significant effect of the slope and position of the material on all the dependent variables studied, as well as the quadratic effect of the slope for the transportation time and total mass transported. As for the rainfall intensity, only influence was observed for transportation time, within the study intervals with a level of significance of 95%. The resulting model is capable of explaining: 90% for transport time, 67.9% for peak value, 74.2% for peak time and 62.4% total mass transported.

8.
Eng. sanit. ambient ; Eng. sanit. ambient;23(2): 405-414, mar.-abr. 2018. tab, graf
Artigo em Português | LILACS | ID: biblio-891636

RESUMO

RESUMO Um dos impactos da urbanização no meio ambiente é a alteração do processo de transformação da chuva em escoamento superficial, levando à alteração da qualidade dos recursos hídricos. Com este trabalho, objetivou-se simular o transporte de partículas em suspensão e de poluentes dissolvidos, transportados pelo escoamento, sobre uma superfície impermeável em escala de laboratório. O modelo experimental consistiu de um simulador para a aplicação de chuva artificial sobre uma superfície acrílica impermeável com 8,40 m2, na qual foram definidas quatro posições para a distribuição do cloreto de sódio e da areia fina, simulando fontes difusas de poluição. Os resultados indicaram diferenças entre os tempos de pico do transporte de poluentes dissolvidos e em suspensão, em função da posição desses. O efeito de first flush foi verificado para os poluentes dissolvidos independentemente da posição da fonte, enquanto para os poluentes transportados em suspensão o mesmo efeito só foi verificado quando a fonte estava mais próxima da saída da superfície impermeável.


ABSTRACT One of the impacts of urbanization on the environment is the changes in the rainfall-runoff process, causing changes in water resources quality. The objective of this project was to simulate the transport of suspended particles and pollutants dissolved on runoff, an impermeable surface at laboratory scale. The experimental model consisted on a simulator for the application of artificial rainfall on an impermeable surface with 8,40 m2, in which sodium chloride and fine sand were distributed in four defined regions, simulating sources of diffuse pollution. The results showed differences between peak transport times of dissolved and suspended pollutants, depending on their position. The first-flush effect was observed for the dissolved pollutants independently of the source position, whereas for the pollutants transported in suspension the same effect was only found when the source was closer to the outlet of the impervious surface.

9.
J Nucl Med ; 54(2): 176-83, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23243299

RESUMO

UNLABELLED: (18)F-FDG PET/CT is used in a variety of cancers, but because of variable rates of glucose metabolism, not all cancers are reliably identified. (18)F(-) PET/CT allows for the acquisition of highly sensitive and specific images of the skeleton. We prospectively evaluated combined (18)F(-)/(18)F-FDG as a single PET/CT examination for evaluation of cancer patients and compared it with separate (18)F(-) PET/CT and (18)F-FDG PET/CT scans. METHODS: One hundred fifteen participants with cancer were prospectively enrolled in an international multicenter trial evaluating (18)F(-) PET/CT, (18)F-FDG PET/CT, and combined (18)F(-)/(18)F-FDG PET/CT. The 3 PET/CT scans were performed sequentially within 4 wk of one another for each patient. RESULTS: (18)F(-)/(18)F-FDG PET/CT allowed for accurate interpretation of radiotracer uptake outside the skeleton, with findings similar to those of (18)F-FDG PET/CT. In 19 participants, skeletal disease was more extensive on (18)F(-) PET/CT and (18)F(-)/(18)F-FDG PET/CT than on (18)F-FDG PET/CT. In another 29 participants, (18)F(-) PET/CT and (18)F(-)/(18)F-FDG PET/CT showed osseous metastases where (18)F-FDG PET/CT was negative. The extent of skeletal lesions was similar in 18 participants on all 3 scans. CONCLUSION: This trial demonstrated that combined (18)F(-)/(18)F-FDG PET/CT shows promising results when compared with separate (18)F(-) PET/CT and (18)F-FDG PET/CT for evaluation of cancer patients. This result opens the possibility for improved patient care and reduction in health-care costs, as will be further evaluated in future trials.


Assuntos
Fluordesoxiglucose F18 , Neoplasias/diagnóstico por imagem , Neoplasias/diagnóstico , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/diagnóstico por imagem , Osso e Ossos/metabolismo , Feminino , Radioisótopos de Flúor , Glucose/metabolismo , Humanos , Processamento de Imagem Assistida por Computador/métodos , Cooperação Internacional , Masculino , Oncologia/métodos , Pessoa de Meia-Idade , Metástase Neoplásica , Medicina Nuclear/métodos , Projetos Piloto , Estudos Prospectivos , Reprodutibilidade dos Testes
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