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Oliveira A, Pereira J, Sarmento S, Pereira M, Cardoso J, Santos L, Alves J, Santos J. Study on the dose profile in CT-fluoroscopy. Appl Radiat Isot 2022; 190:110516. [DOI: 10.1016/j.apradiso.2022.110516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 10/03/2022] [Accepted: 10/12/2022] [Indexed: 11/02/2022]
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O'Connor U, Carinou E, Clairand I, Ciraj-Bjelac O, De Monte F, Domienik-Andrzejewska J, Ferrari P, Ginjaume M, Hršak H, Hupe O, Knežević Ž, Sans Merce M, Sarmento S, Siiskonen T, Vanhavere F. Recommendations for the use of active personal dosemeters (APDs) in interventional workplaces in hospitals. Phys Med 2021; 87:131-135. [PMID: 34153572 DOI: 10.1016/j.ejmp.2021.05.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Revised: 05/04/2021] [Accepted: 05/08/2021] [Indexed: 10/21/2022] Open
Abstract
Occupational radiation doses from interventional procedures have the potential to be relatively high. The requirement to optimise these doses encourages the use of electronic or active personal dosimeters (APDs) which are now increasingly used in hospitals. They are typically used in tandem with a routine passive dosimetry monitoring programme, with APDs used for real-time readings, for training purposes and when new imaging technology is introduced. However, there are limitations when using APDs. A survey in hospitals to identify issues related to the use of APDs was recently completed, along with an extensive series of APD tests by the EURADOS Working Group 12 on Dosimetry for Medical Imaging. The aim of this review paper is to summarise the state of the art regarding the use of APDs. We also used the results of our survey and our tests to develop a set of recommendations for the use of APDs in the clinical interventional radiology/cardiology settings, and draw attention to some of the current challenges.
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Affiliation(s)
| | - E Carinou
- Greek Atomic Energy Commission, EEAE, Agia Paraskevi, Attiki, Greece
| | - I Clairand
- IRSN, Institute for Radiological Protection and Nuclear Safety, Fontenay-aux-Roses, France
| | - O Ciraj-Bjelac
- Vinca Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - F De Monte
- Veneto Institute of Oncology IOV-IRCCS, Padua, Italy
| | | | - P Ferrari
- ENEA. IRP-Radiation Protection Institute, Bologna, Italy
| | - M Ginjaume
- UPC, Universitat Politècnica de Catalunya, Barcelona, Spain
| | - H Hršak
- University Hospital Centre Zagreb, Croatia
| | - O Hupe
- Physikalisch-Technische Bundesanstalt (PTB), 38116 Braunschweig, Germany
| | - Ž Knežević
- Ruđer Bošković Institute RBI, Zagreb, Croatia
| | - M Sans Merce
- CHUV, University Hospital of Lausanne, Lausanne, Switzerland; HUG, University Hospital of Geneva, Geneva, Switzerland
| | - S Sarmento
- IPO Porto Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Porto, Portugal
| | | | - F Vanhavere
- SCK-CEN, Belgian Nuclear Research Centre, Mol, Belgium
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Vanhavere F, Carinou E, Clairand I, Ciraj-Bjelac O, De Monte F, Domienik-Andrzejewska J, Ferrari P, Ginjaume M, Hršak H, Hupe O, Knezevic Z, O'Connor U, Merce MS, Sarmento S, Savary A, Siskoonen T. THE USE OF ACTIVE PERSONAL DOSEMETERS IN INTERVENTIONAL WORKPLACES IN HOSPITALS: COMPARISON BETWEEN ACTIVE AND PASSIVE DOSEMETERS WORN SIMULTANEOUSLY BY MEDICAL STAFF. Radiat Prot Dosimetry 2020; 188:22-29. [PMID: 31832653 DOI: 10.1093/rpd/ncz253] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Revised: 05/11/2019] [Accepted: 07/12/2019] [Indexed: 06/10/2023]
Abstract
Medical staff in interventional procedures are among the professionals with the highest occupational doses. Active personal dosemeters (APDs) can help in optimizing the exposure during interventional procedures. However, there can be problems when using APDs during interventional procedures, due to the specific energy and angular distribution of the radiation field and because of the pulsed nature of the radiation. Many parameters like the type of interventional procedure, personal habits and working techniques, protection tools used and X-ray field characteristics influence the occupational exposure and the scattered radiation around the patient. In this paper, we compare the results from three types of APDs with a passive personal dosimetry system while being used in real clinical environment by the interventional staff. The results show that there is a large spread in the ratios of the passive and active devices.
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Affiliation(s)
- F Vanhavere
- SCK-CEN, Belgian Nuclear Research Centre, Mol, Belgium
| | - E Carinou
- Greek Atomic Energy Commission, EEAE, Agia Paraskevi, Attiki, Greece
| | - I Clairand
- IRSN, Institute for Radiological Protection and Nuclear Safery, Fontenay-Aux-Roses, France
| | - O Ciraj-Bjelac
- Vinca Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - F De Monte
- Veneto Institute of Oncology IOV-IRCCS, Padua, Italy
| | | | - P Ferrari
- ENEA. IRP-Radiation Protection Institute, Bologna, Italy
| | - M Ginjaume
- UPC, Universitat Politècnica de Catalunya, Barcelona, Spain
| | | | - O Hupe
- Physikalisch-Technische Bundesanstalt (PTB), 38116 Braunschweig, Germany
| | - Z Knezevic
- Ruder Boskovic Institute RBI, Zagreb, Croatia
| | | | - M Sans Merce
- CHUV, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - S Sarmento
- Porto Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Porto, Portugal
| | - A Savary
- IRSN, Institute for Radiological Protection and Nuclear Safery, Fontenay-Aux-Roses, France
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Alves JG, Sarmento S, Pereira JS, Pereira MF, Sousa MJ, Cunha L, Dias A, Oliveira AD, Cardoso JV, Santos LM, Lencart J, Gouvêa M, Santos JAM. Dose to the interventional radiologist in CTF-guided procedures. Radiat Environ Biophys 2019; 58:373-384. [PMID: 30993431 DOI: 10.1007/s00411-019-00792-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 04/06/2019] [Indexed: 06/09/2023]
Abstract
The aim of this work was to assess the occupational dose received by an interventional radiologist (IR) during computed tomography fluoroscopy (CTF)-guided procedures; to identify the most exposed areas of the body including the hands and fingers; to suggest recommendations for individual monitoring; and to improve radiation safety of the practice. A total of 53 CTF-guided procedures were studied. Twelve whole-body dosimeters were worn by the IR in each procedure for the assessment of the personal dose equivalent, Hp(10), on the chest, waist, and back, both over and under the lead apron, as well as the personal dose equivalent, Hp(0.07), on both arms, knees, and feet. Special gloves with casings to fit extremity dosimeters were prepared to assess Hp(0.07) to the fingers. The measured chest dose values were higher than those on the waist and back; the dominant hand or the left side was the most exposed. In general, the ring, middle, and index fingers of the dominant hand were the most exposed (maximum in the 36-39 mSv range), while wrist dose was negligible compared to finger doses. Based on the results obtained the following recommendations are suggested: protective devices (lead aprons, thyroid shield, and goggles) should be worn; Hp(10) should be assessed at the chest level both above and below the lead apron; finger doses can be measured on the basis of each middle finger; the arm closer to the beam should be monitored; and finally, a wrist dosimeter will not provide useful information.
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Affiliation(s)
- J G Alves
- Instituto Superior Técnico (IST), Laboratório de Proteção e Segurança Radiológica (LPSR), Universidade de Lisboa (UL), Estrada Nacional 10 (ao km 139,7), 2695-066, Bobadela LRS, Portugal.
- Departamento de Engenharia e Ciências Nucleares (DECN), Centro de Ciências e Tecnologias Nucleares (C2TN), UL-IST, Bobadela LRS, Portugal.
| | - S Sarmento
- Instituto Português de Oncologia do Porto Francisco Gentil, EPE (IPOPFG E.P.E.), Serviço de Física Médica, Rua Dr. António Bernardino de Almeida, 4200-072, Porto, Portugal
- Centro de Investigação, IPOPFG E.P.E., Porto, Portugal
| | - J S Pereira
- Instituto Superior Técnico (IST), Laboratório de Proteção e Segurança Radiológica (LPSR), Universidade de Lisboa (UL), Estrada Nacional 10 (ao km 139,7), 2695-066, Bobadela LRS, Portugal
- Departamento de Engenharia e Ciências Nucleares (DECN), Centro de Ciências e Tecnologias Nucleares (C2TN), UL-IST, Bobadela LRS, Portugal
| | - M F Pereira
- Instituto Superior Técnico (IST), Laboratório de Proteção e Segurança Radiológica (LPSR), Universidade de Lisboa (UL), Estrada Nacional 10 (ao km 139,7), 2695-066, Bobadela LRS, Portugal
- Departamento de Engenharia e Ciências Nucleares (DECN), Centro de Ciências e Tecnologias Nucleares (C2TN), UL-IST, Bobadela LRS, Portugal
| | - M J Sousa
- Serviço de Radiologia de Intervenção, IPOPFG E.P.E., Porto, Portugal
| | - L Cunha
- Instituto Português de Oncologia do Porto Francisco Gentil, EPE (IPOPFG E.P.E.), Serviço de Física Médica, Rua Dr. António Bernardino de Almeida, 4200-072, Porto, Portugal
- Centro de Investigação, IPOPFG E.P.E., Porto, Portugal
| | - A Dias
- Instituto Português de Oncologia do Porto Francisco Gentil, EPE (IPOPFG E.P.E.), Serviço de Física Médica, Rua Dr. António Bernardino de Almeida, 4200-072, Porto, Portugal
- Centro de Investigação, IPOPFG E.P.E., Porto, Portugal
| | - A D Oliveira
- Instituto Superior Técnico (IST), Laboratório de Proteção e Segurança Radiológica (LPSR), Universidade de Lisboa (UL), Estrada Nacional 10 (ao km 139,7), 2695-066, Bobadela LRS, Portugal
- Departamento de Engenharia e Ciências Nucleares (DECN), Centro de Ciências e Tecnologias Nucleares (C2TN), UL-IST, Bobadela LRS, Portugal
| | - J V Cardoso
- Instituto Superior Técnico (IST), Laboratório de Proteção e Segurança Radiológica (LPSR), Universidade de Lisboa (UL), Estrada Nacional 10 (ao km 139,7), 2695-066, Bobadela LRS, Portugal
| | - L M Santos
- Instituto Superior Técnico (IST), Laboratório de Proteção e Segurança Radiológica (LPSR), Universidade de Lisboa (UL), Estrada Nacional 10 (ao km 139,7), 2695-066, Bobadela LRS, Portugal
| | - J Lencart
- Instituto Português de Oncologia do Porto Francisco Gentil, EPE (IPOPFG E.P.E.), Serviço de Física Médica, Rua Dr. António Bernardino de Almeida, 4200-072, Porto, Portugal
| | - M Gouvêa
- Serviço de Radiologia, IPOPFG E.P.E., Porto, Portugal
| | - J A M Santos
- Instituto Português de Oncologia do Porto Francisco Gentil, EPE (IPOPFG E.P.E.), Serviço de Física Médica, Rua Dr. António Bernardino de Almeida, 4200-072, Porto, Portugal
- Centro de Investigação, IPOPFG E.P.E., Porto, Portugal
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Teles P, Nikodemová D, Bakhanova E, Becker F, Kneževic Ž, Pereira MF, Sarmento S. A Review of Radiation Protection Requirements and Dose Estimation for Staff and Patients in CT Fluoroscopy. Radiat Prot Dosimetry 2017; 174:518-534. [PMID: 27522054 DOI: 10.1093/rpd/ncw231] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 07/06/2016] [Indexed: 06/06/2023]
Abstract
The combination of fluoroscopically guided interventional procedures with computed tomography (CTF) has become widespread around the world. The benefits of CTF include the ability to obtain a real-time visualization of the entire body, increased target accuracy and improved visualization of biopsy needles. Modern CTF units work with variable frame rates for image selection, and therefore the dose distributions for patients and staff can considerably vary, creating growing concern in terms of the occupational exposure of interventionists and the drawback of a higher exposure of the patient. A literature review of the latest CTF publications is summarized in this article. A wide range of CTF studies reveal different treatment methods used in clinical practice, and therefore the differences in the exposures between them; as well as in the radiation protection tools and dose monitoring. Further optimization of radiation protection methods, harmonization of exposure patterns as well as training and education of CTF staff on the basis of the information in the survey, are strongly recommended.
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Affiliation(s)
- P Teles
- Grupo de Proteção e Segurança Radiológica, Centro de Ciências e Tecnologias Nucleares (C2TN), Instituto Superior Técnico, Universidade de Lisboa, Pólo de Loures. Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal
| | - D Nikodemová
- Slovak Medical University, Limbová 14, 83301 Bratislava, Slovakia
| | - E Bakhanova
- National Research Center for Radiation Medicine, NAMS Ukraine, Melnikova 53, Kiev 04050, Ukraine
| | - F Becker
- Institute for Nuclear Waste Disposal, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Ž Kneževic
- Ruder Boškovic Institute, Bijenicka 54, 10000 Zagreb, Croatia
| | - M F Pereira
- Grupo de Proteção e Segurança Radiológica, Centro de Ciências e Tecnologias Nucleares (C2TN), Instituto Superior Técnico, Universidade de Lisboa, Pólo de Loures. Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal
- Laboratório de Proteção e Segurança Radiológica (LPSR), Instituto Superior Técnico, Universidade de Lisboa, Pólo de Loures. Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal
| | - S Sarmento
- Medical Physics, Radiobiology and Radiation Protection Group, IPO Porto Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Porto, Portugal
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Pereira J, Pereira M, Sarmento S, Oliveira A, Alves J, Sousa M, Cunha L, Dias A, Mendes B, Cardoso J, Santos L, Gouvêa M, Santos J. Patient surface and isocenter dose in FLUORO-CT. Phys Med 2016. [DOI: 10.1016/j.ejmp.2016.07.232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Mendes B, Dias F, Oliveira D, Sarmento S. Assessing the feasibility of simulating different tube current limits in noise oriented ATCM systems. Phys Med 2016. [DOI: 10.1016/j.ejmp.2016.07.178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Costa F, Sarmento S, Sousa O. PD-0572: In vivo dosimetry using Gafchromic films during IOERT of rectal cancer. Radiother Oncol 2015. [DOI: 10.1016/s0167-8140(15)40566-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Cruz AMJ, Sarmento S, Almeida SM, Silva AV, Alves C, Freitas MC, Wolterbeek H. Association between atmospheric pollutants and hospital admissions in Lisbon. Environ Sci Pollut Res Int 2015; 22:5500-10. [PMID: 25471710 DOI: 10.1007/s11356-014-3838-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 11/10/2014] [Indexed: 05/27/2023]
Abstract
Ambient air pollution is recognised as one of the potential environmental risk factors causing health hazards to the exposed population, demonstrated in numerous previous studies. Several longitudinal, ecological and epidemiological studies have shown associations between outdoor levels of outdoor atmospheric pollutants and adverse health effects, especially associated with respiratory and cardiovascular hospital admissions. The aim of this work is to assess the influence of atmospheric pollutants over the hospital admissions in Lisbon, by Ordinary Least Squares Linear Regression. The pollutants (CO, NO, NO2, SO2, O3, PM10 and PM2.5) were obtained from 13 monitoring stations of the Portuguese Environmental Agency, which provide hourly observations. Hospital admission data were collected from the Central Administration of the Health System and were compiled by age: <15, 15-64, >64 years old. The study period was 2006-2008. Results showed significant positive associations between the following: (1) the pollutants CO, NO, NO2, SO2, PM10 and PM2.5 and circulatory diseases for ages between 15 and 64 years (0.5% hospital admissions (HA) increase with 10 μg m(-3) NO increase) and above 64 years (1.0% stroke admission increase with 10 μg m(-3) NO2 increase); (2) the pollutants CO, NO, NO2, SO2, PM10 and PM2.5 and respiratory diseases for ages below 15 years (up to 1.9% HA increase with 10 μg m(-3) pollutant increase); and (3) the pollutants NO, NO2 and SO2 and respiratory diseases for ages above 64 years (1.3% HA increase with 10 μg m(-3) CO increase).
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Affiliation(s)
- A M J Cruz
- Escola Superior de Tecnologia e Gestão de Oliveira do Hospital, Instituto Politécnico de Coimbra, Rua General Santos Costa, 3400-124, Oliveira do Hospital, Portugal,
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Almeida SM, Silva AV, Sarmento S. Effects of exposure to particles and ozone on hospital admissions for cardiorespiratory diseases in SetúBal, Portugal. J Toxicol Environ Health A 2014; 77:837-848. [PMID: 25072716 DOI: 10.1080/15287394.2014.887399] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In recent years, the adverse health effects attributed to air pollution have been a focus of intense study. Exposure to pollutants such as airborne particulate matter (PM) and ozone (O3) has been associated with increases in morbidity and mortality due to respiratory and cardiovascular diseases. The aim of this study was to determine a correlation between particles (PM10, PM2.5) and O3 with hospital admissions in Setúbal, a densely populated Portuguese urban region that coexists with a heavy industrial area. A database with daily air quality and hospital admission data over 5 years (2005-2009) was assembled and associations were investigated by ordinary least squares linear regression. Results showed positive significant associations between PM10 and respiratory diseases for ages below 14 yr and above 64 yr, and between PM2.5 and respiratory diseases for ages above 64 yr.
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Affiliation(s)
- S M Almeida
- a C2TN, Instituto Superior Técnico, Universidade de Lisboa , Bobadela LRS , Portugal
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12
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Pereira MF, Alves JG, Sarmento S, Santos JAM, Sousa MJ, Gouvêa M, Oliveira AD, Cardoso JV, Santos LM. Preliminary assessment of the dose to the interventional radiologist in fluoro-CT-guided procedures. Radiat Prot Dosimetry 2011; 144:448-452. [PMID: 21112883 DOI: 10.1093/rpd/ncq418] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A preliminary assessment of the occupational dose to the intervention radiologist received in fluoroscopy computerised tomography (CT) used to guide the collection of lung and bone biopsies is presented. The main aim of this work was to evaluate the capability of the reading system as well as of the available whole-body (WB) and extremity dosemeters used in routine monthly monitoring periods to measure per procedure dose values. The intervention radiologist was allocated 10 WB detectors (LiF: Mg, Ti, TLD-100) placed at chest and abdomen levels above and below the lead apron, and at both right and left arms, knees and feet. A special glove was developed with casings for the insertion of 11 extremity detectors (LiF:Mg, Cu, P, TLD-100H) for the identification of the most highly exposed fingers. The H(p)(10) dose values received above the lead apron (ranged 0.20-0.02 mSv) depend mainly on the duration of the examination and on the placement of physician relative to the beam, while values below the apron are relatively low. The left arm seems to receive a higher dose value. H(p)(0.07) values to the hand (ranged 36.30-0.06 mSv) show that the index, middle and ring fingers are the most highly exposed. In this study, the wrist dose was negligible compared with the finger dose. These results are preliminary and further studies are needed to better characterise the dose assessment in CT fluoroscopy.
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Affiliation(s)
- M F Pereira
- Instituto Tecnológico e Nuclear, Unidade de Protecção e Segurança Radiológica, EN10, 2686-953 Sacavém, Portugal.
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Sarmento S, Wolterbeek HT, Verburg TG, Freitas MC. Correlating element atmospheric deposition and cancer mortality in Portugal: data handling and preliminary results. Environ Pollut 2008; 151:341-51. [PMID: 17688980 DOI: 10.1016/j.envpol.2007.06.039] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2007] [Accepted: 06/17/2007] [Indexed: 05/16/2023]
Abstract
This study, framed within geographical epidemiology, presents preliminary findings concerning the association between the concentrations of chemical elements obtained through atmospheric biomonitoring with lichens and cancer mortality in the Portuguese population. Exploratory analyses were performed to identify potential confounders for the relationships between chemical elements and neoplasm mortality and to assess the extent of their interference. The results of this study highlight some methodological and conceptual difficulties inherent to observational and geographical studies, in the specific context of the Portuguese population, and the challenge posed by the large numbers of pollutants considered.
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Affiliation(s)
- S Sarmento
- Department of Radiation, Radionuclides & Reactors, Section RIH (Radiation and Isotopes in Health), Faculty of Applied Sciences, Technical University of Delft, Mekelweg 15, Delft, The Netherlands.
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Santos JAM, Sarmento S, Alves P, Torres MC, Bastos AL, Ponte F. Single-acquisition method for simultaneous determination of extrinsic gamma-camera sensitivity and spatial resolution. Appl Radiat Isot 2007; 66:44-9. [PMID: 17855102 DOI: 10.1016/j.apradiso.2007.07.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2007] [Revised: 06/18/2007] [Accepted: 07/23/2007] [Indexed: 11/27/2022]
Abstract
A new method for measuring simultaneously both the extrinsic sensitivity and spatial resolution of a gamma-camera in a single planar acquisition was implemented. A dual-purpose phantom (SR phantom; sensitivity/resolution) was developed, tested and the results compared with other conventional methods used for separate determination of these two important image quality parameters. The SR phantom yielded reproducible and accurate results, allowing an immediate visual inspection of the spatial resolution as well as the quantitative determination of the contrast for six different spatial frequencies. It also proved to be useful in the estimation of the modulation transfer function (MTF) of the image formation collimator/detector system at six different frequencies and can be used to estimate the spatial resolution as function of the direction relative to the digital matrix of the detector.
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Affiliation(s)
- J A M Santos
- Serviço de Física Médica, Instituto Português de Oncologia Francisco Gentil do Porto, E.P.E., Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal.
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Nguyen HT, Rouillon JC, Marcerou JP, Bedel JP, Barois P, Sarmento S. Mesomorphic and Electro-Optical Properties of New Achiral Banana-Shaped Molecules. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/10587259908026057] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Boyes A, Chughtai A, Lu X, Raymahasay S, Sarmento S, Tilston M, Winterbottom J. The cocurrent downflow contactor (CDC) reactor-chemically enhanced mass transfer & reaction studies for slurry & fixed bed catalytic hydrogenation. Chem Eng Sci 1992. [DOI: 10.1016/0009-2509(92)85091-o] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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