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- 10 kVp rule - An anthropomorphic pelvis phantom imaging study using a CR system: impact on image quality and effective dose using AEC and manual modePublication . Lança, Luís; Franco, L.; Ahmed, A.; Harderwijk, M.; Nasir, S.; Ndlovu, J.; Oliveira, M.; Santiago, A.; Hogg, PeterPurpose: This study aims to investigate the influence of tube potential (kVp) variation in relation to perceptual image quality and effective dose for pelvis using automatic exposure control (AEC) and non-AEC in a computed radiography (CR) system. Methods and Materials: To determine the effects of using AEC and non-AEC by applying the 10 kVp rule in two experiments using an anthropomorphic pelvis phantom. Images were acquired using 10 kVp increments (60-120 kVp) for both experiments. The first experiment, based on seven AEC combinations, produced 49 images. The mean mAs from each kVp increment were used as a baseline for the second experiment producing 35 images. A total of 84 images were produced and a panel of 5 experienced observers participated for the image scoring using the 2 AFC visual grading software. PCXMC software was used to estimate the effective dose. Results: A decrease in perceptual image quality as the kVp increases was observed both in non-AEC and AEC experiments, however no significant statistical differences (p> 0.05) were found. Image quality scores from all observers at 10 kVp increments for all mAs values using non-AEC mode demonstrates a better score up to 90 kVp. Effective dose results show a statistical significant decrease (p=0.000) on the 75th quartile from 0.3 mSv at 60 kVp to 0.1 mSv at 120 kVp when applying the 10 kVp rule in non-AEC mode. Conclusion: No significant reduction in perceptual image quality is observed when increasing kVp whilst a marked and significant effective dose reduction is observed.
- 10 kVp rule – An anthropomorphic pelvis phantom imaging study using a CR system: impact on image quality and effective dose using AEC and manual modePublication . Lança, Luís; Franco, L.; Ahmed, A.; Harderwijk, M.; Marti, C.; Nasir, S.; Ndlovu, J.; Oliveira, M.; Santiago, A.; Hogg, PeterBackground - Pelvis and hip radiography are consistently found to be amongst the highest contributors to the collective effective dose (E) in all ten DOSE DATAMED countries in Europe, representing 2.8 to 9.4% of total collective dose (S) in the TOP 20 exams list. The level of image quality should provide all the diagnostic information in order not to jeopardise the diagnosis, but being able to provide the needed clinical information with the minimum dose. A recent study suggests further research to determine whether the “10 kVp rule” would have value for a range of examinations using Computed Radiography (CR) systems. As a “rule of thumb” increasing the kVp by 10 whilst halving the mAs is suggested to give a similar perceptual image quality when compared to the original exposure factors. Aims - In light of the 10kVp rule, this study aims to investigate the influence of tube potential (kVp) variation in relation to perceptual image quality and E for pelvis imaging using automatic exposure control (AEC) and non-AEC in a Computed Radiography (CR) system. Research questions - Does the 10kVp rule works for the pelvis in relation to image quality in a CR system? Does the image quality differs when the AEC is used instead of manual mode using the 10kVp rule and how this impacts on E?
- 100 Años de desarrollo de la teoría financiera : situación actual y previsible evolución tras la crisis : resumen de la ponenciaPublication . Gómez-Bezares, Fernando"Las Finanzas, como disciplina académica, nacen a caballo entre los siglos XIX y XX. Sin duda el importante desarrollo industrial de la época y la necesidad de empresas de mayores dimensiones llevaron a un creciente interés por las concentraciones empresariales como fusiones y adquisiciones. También aumentó el interés por los mercados donde se financiaban estas empresas cada vez mayores. Y esto, aunque sucedía en diversas partes del mundo, estaba ocurriendo de forma especial en Estados Unidos, de manera que allí fue donde nacieron las finanzas, y donde se han seguido desarrollando. De esta manera, desde un comienzo, las finanzas tienen un claro sello anglosajón." [introdução]
- 131I therapy in thyroid cancer and benign thyroid diseases: personal dose equivalent HP(10) assessment in patient’s close family membersPublication . Raminhas Carapinha, Maria João; Costa, Gracinda; Ferreira, Teresa C.; Salgado, Lucília; Vaz, Sofia; Ferreira, Rui; Isidoro, Jorge; Rézio, Teresa; Nunes, Carla; Tavares, António Barata; Vaz, PedroIntroduction - The aim is to quantify the personal dose equivalent HP(10) in the family members (FMs) of the patients (PATs) undergoing iodine-131 thyroid cancer (TC) therapy and benign thyroid diseases (BTD) and to compare the HP(10) values of children and adults. Methods - An observational study with convenience sampling was performed, including 83 FMs (59% ♂) of 48 PATs (72.9% ♀). All FMs wore a whole body TLD for 21 days and received instructions on radiation protection, based on Euratom recommendations. All FMs were provided with relevant instructions for TLD use and answered a questionnaire. Two groups were defined: Group-TC, included 65 FMs (5 children below the age of 10) of 37 PATs treated for TC with average (ᾱ) activity of 3434MBq (range 1110–5920MBq); Group-BTD included 18 FMs adults of 11 PATs treated for BTD with ᾱ activity of 336.4MBq (range 185–555MBq). The in-PATs of Group-TC were discharged 48h after therapy. All ethical principles of the investigation were respected. Results - When the PATs of Group-TC were discharged the ᾱ effective dose rate measured at a 1-metre distance was 10.4μSv/h (range 2–28μSv/h). The ᾱ value of HP(10) in FMs were: 0.14mSv (range 0.00-3.37mSv) for Group-TC and 0.37mSv (range 0.01-2.40mSv) for Group-BTD. The HP(10) value depended on the degree of relationship (p=0.008) and the age of the FMs (p=0.007). HP(10) of the FMs were moderately associated to administered activity (ρsp=-0.319; p=0.010) in Group-TC. No association was found between HP(10) FMs and the administered activity in Group-BTD (ρsp=0.139; p=0.583). Conclusions - The FMs of the PATs submitted 131I therapy for BTD received higher doses when compared to FMs of TC PATs. The HP(10) of the FMs depended to the degree of relationship and the age of the FMs. In the PATs submitted 131I therapy for BTD, the HP(10) of the FMs is not associated with the administered activity. The personal dose equivalent in these FMs does not reach the dose limits recommended by ICRP 97 and ICRP 94.
- 18F-FDG measurement in primary lung cancer: SUV normalization to different distribution volumesPublication . Badgi, Estevão; Santos, Beatriz; Lucena, Filipa; Conde, IsabelIntroduction: Standard Uptake Value (SUV) is a measurement of the uptake in a tumour normalized on the basis of a distribution volume and is used to quantify 18F-Fluorodeoxiglucose (FDG) uptake in tumors, such as primary lung tumor. Several sources of error can affect its accuracy. Normalization can be based on body weight, body surface area (BSA) and lean body mass (LBM). The aim of this study is to compare the influence of 3 normalization volumes in the calculation of SUV: body weight (SUVW), BSA (SUVBSA) and LBM (SUVLBM), with and without glucose correction, in patients with known primary lung tumor. The correlation between SUV and weight, height, blood glucose level, injected activity and time between injection and image acquisition is evaluated. Methods: Sample included 30 subjects (8 female and 22 male) with primary lung tumor, with clinical indication for 18F-FDG Positron Emission Tomography (PET). Images were acquired on a Siemens Biography according to the department’s protocol. Maximum pixel SUVW was obtained for abnormal uptake focus through semiautomatic VOI with Quantification 3D isocontour (threshold 2.5). The concentration of radioactivity (kBq/ml) was obtained from SUVW, SUVBSA, SUVLBM and the glucose corrected SUV were mathematically obtained. Results: Statistically significant differences between SUVW, SUVBSA and SUVLBM and between SUVWgluc, SUVBSAgluc and SUVLBMgluc were observed (p=0.000<0.05). The blood glucose level showed significant positive correlations with SUVW (r=0.371; p=0.043) and SUVLBM (r=0.389; p=0.034). SUVBSA showed independence of variations with the blood glucose level. Conclusion: The measurement of a radiopharmaceutical tumor uptake normalized on the basis of different distribution volumes is still variable. Further investigation on this subject is recommended.
- 18FDG PET/CT in the qualitative and quantitative evaluation of the therapeutic response in Hodgkin’s lymphomaPublication . Martins, Nuno; Hunter, James; Vaz, Tânia; Dizdarevic, Sabina
- 1as Jornadas de Engenharia CivilPublication . Instituto Superior de Engenharia de Lisboa1as Jornadas de Engenharia Civil: Medir e modular - Herberto Miranda Construção civil industrializada - Brazão Farinha Industrialização da construção de edifício - Teixeira Trigo Paredes pré-fabricadas/pesadas - A. Almeida Anes Paredes de betão - Luís Rodrigues dos Santos Coberturas de grandes vãos - João Apletton Nacionalização da construção - Nuno Patrício e Boadita Ferrão Cálculo de pavimentos - Elias da Costa Ventilação técnica "Féria" - Tipo Shunt - Serviços Técnicos da Féria
- 2007: a odisseia da bibliotecaPublication . Marques, Ricardo DiasComunicação Painel 1 | Sistema KOHA uma retrospetiva: Há 10 anos, em 2007, o Koha em Portugal estava ainda na sua infância. Esta apresentação é o relato da transição de um software proprietário de gestão de Bibliotecas, para o Koha, na Biblioteca do ex-Instituto de Informática do Ministério das Finanças (um dos organismos públicos que deram lugar à atual eSPap). Também serão mencionados algumas contribuições feitas para a Comunidade (manual de instalação em openSUSE; tradução para Português; "patches"...). Finalmente, será brevemente referido um projeto de implementação do Koha, no Ministério das Finanças de Cabo Verde, em projeto conduzido pela SGMF (Secretaria-Geral do Ministério das Finanças de Portugal).
- 25 Anos de diagnóstico em fisiopatologia respiratóriaPublication . Dias, Hermínia Brites
- O 25 de Novembro de 1975 pelas lentes do fotojornalismoPublication . Mata, Maria J.; Cardoso, Carla Rodrigues; Gomes, Pedro MarquesEsta comunicação percorre a narrativa fotojornalística construída pela imprensa portuguesa em torno dos acontecimentos de 25 de Novembro de 1975, momento que põe termo ao chamado "Processo Revolucionário em Curso" (PREC). Durante a "Revolução dos Cravos" sucederam-se golpes e contragolpes, levados a cabo por forças políticas e militares, que divergiam sobre a natureza do regime político a implementar em Portugal, após o fim de mais de quatro décadas de ditadura. A narrativa histórica do golpe de 25 de Novembro aponta para o culminar desse processo divisório, com a derrota da extrema esquerda a permitir a clarificação do modelo político a seguir e a transferência da esfera de poder do domínio militar para o domínio civil. Inicia-se, então, uma nova fase política: a institucionalização da democracia portuguesa. De que modo é que essa derrota foi contada pelas lentes do fotojornalismo? Até que ponto a narrativa fotográfica evidencia vencedores e vencidos? Partindo destas questões exploratórias, procede-se à análise de conteúdo das peças sobre o 25 de Novembro, focando-nos nas imagens e na sua relação com os títulos, em seis jornais (quatro diários e dois semanários) e uma revista semanal de informação geral: A Capital, Diário Popular, Comércio do Porto, República (diários); Expresso e O Jornal (semanários); e Flama (newsmagazine). Embora alguns jornais e revistas tenham sido silenciados e impedidos de circular nos dias imediatos, o trabalho dos fotojornalistas foi fundamental para a reconstituição visual dos momentos mais marcantes do golpe permitindo, ao longo das 210 imagens do corpus, identificar o protagonismo dos militares e o foco dado às suas movimentações, e evidenciar uma construção da narrativa associada à vitória/derrota que varia entre títulos.