Radiation protection dosimetry最新文献

{"title":"Evaluation of the environmental and structural impacts on urban expansion using airborne geophysical data at Hurghada city, Northern Eastern Desert, Egypt.","authors":"Reda Abdu Yousef El-Qassas","doi":"10.1093/rpd/ncae135","DOIUrl":"10.1093/rpd/ncae135","url":null,"abstract":"<p><p>Airborne gamma-ray spectrometric and magnetic data were processed and interpreted aiming to evaluate the environmental and structural impacts on urban expansion, Hurghada City, Northern Eastern Desert, Egypt. The eastern (coastal area), northern, and southeastern parts of the study area possess the lowest level of absorbed dose rate (ADR) and annual effective dose equivalent (AEDE), which were estimated from the airborne gamma-ray spectral data of this area. Consequently, these parts are considered as suitable sites for urban expansion from the radioactivity point of view. The relatively high level of ADR and AEDE is associated with granitic rocks, some parts of Gabir formation and recent Wadi sediments, situated at southwestern, central, and eastern parts of the study area. The ADR and AEDE of these parts are considered harmful to individuals. Airborne magnetic data were also used to detect major structures that may affect various construction projects in the study area in the future. The NNW-SSE, NW-SE, N-S, and NE-SW trends represent the common structures in the study area. The obtained results of airborne gamma-ray spectrometric and magnetic data illustrated that the urban expansion should not be constructed to the west of the ring road. However, site investigations must be carried out on this part of the study area before starting any construction projects there. The present study proved the important role of airborne gamma-ray spectrometric and magnetic surveys as useful tools to delineate the environmental and structural impacts on urban expansion.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2024-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141248454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Indoor concentrations of radioactive aerosols from nuclear accidents.","authors":"Momen Orabi","doi":"10.1093/rpd/ncae131","DOIUrl":"10.1093/rpd/ncae131","url":null,"abstract":"<p><p>In previous studies, some of the important factors that affect the spread of radioactive aerosols into indoors were considered. The studies were based on a new CFD approach and provided good descriptions for the deposition of aerosol particles inside small spaces and the penetration of aerosols into buildings through wall cracks. In this article, an application of those studies is implemented, where all the graphical relations that are required to estimate the indoor concentrations of radioactive aerosols from nuclear accidents are provided. This includes the deposition velocities, deposition rate, and the penetration factor. Particular interest is in the Fukushima-Daiichi nuclear power plant accident that took place in Japan in 2011. The aerosols carrying the radioiodine iodine-131 and the radiocesium cesium-134 and cesium-137 are studied. Based on the model's assumptions, and assuming steady-state air concentrations, the radioactive aerosols' concentrations in indoor air are about 97% of the concentrations in outdoor air. The applications demonstrate the model to be convenient and practical.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2024-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141248455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A survey on mean glandular dose in mammography examination and the factors affecting it in Shahid Sadoughi Hospital, Yazd, Iran.","authors":"Najmeh Asadollahzadeh, SeidKazem Razavi, Mohammad Hossein Zare","doi":"10.1093/rpd/ncae121","DOIUrl":"10.1093/rpd/ncae121","url":null,"abstract":"<p><strong>Background: </strong>mammography is the gold standard in the early detection of breast cancer. Due to the increase in the rate of women suffering from this malignancy all over the world, this imaging modality has been widely used. Considering the side effects caused by ionizing radiation to measure the carcinogenic risk of mammography X-rays, mean glandular dose (MGD) is the best parameter to evaluate the dose received by patients undergoing mammography. The aims of this study were to measure MGD in mammography in mammographic craniocaudal (CC) and mediolateral oblique (MLO) projections and investigate the relationship of MGD with compressed breast thickness (CBT), body mass index, age of the patient, and device exposure conditions.</p><p><strong>Materials and methods: </strong>this cross-sectional analytical study was conducted on women aged 30-70 referring to the mammography unit of Shahid Sadoughi Hospital in Yazd city from May to August 2022. The TLD-GR 200 (thermoluminescence dosimeter) was placed on the breast of the patients for CC and MLO projections, and then the MGD was obtained by multiplying the entrance surface dose and the normalized glandular dose. Analysis of data (such as demographic information of patients, CBT, kVp, and mAs) was done by SPSS 23 software. The normality of the data was checked using Shapiro-Wilk tests. It was found that except for age, other variables did not have a normal distribution; therefore, equivalent parametric and nonparametric tests were used. In this regard, Spearman's correlation was used to assess the correlation between variables. P-value < .05 was considered as level of significance.</p><p><strong>Results: </strong>The mean ± standard deviation (SD) age of patients was 47.3 ± 7.1 years. The median ± IQR (the interquartile range (IQR) is a measure of statistical dispersion, which is the spread of the data. It is defined as the difference between the 75th and 25th percentiles of the data.) (mean ± SD) value of MGD per woman was 1.2 ± 0.4 mGy (1.3 ± 0.3 mGy). The median ± IQR MGD in the MLO and CC projections was 1.6 ± 0.6 mGy and 0.9 ± 0.4 mGy, respectively. Significant relationships (P-value ≤ .001) were observed between MGD with CBT (R = 0.62) and age (R = -0.85).</p><p><strong>Conclusion: </strong>The results showed that the mammography unit at Shahid Sadoughi Hospital in Yazd is functioning properly. The calculated median ± IQR MGD per woman referring to this unit (1.2 ± 0.4 mGy) was clearly below the dose limit recommended by American College of Radiology and International Commission on Radiological Protection (3 mGy). Moreover, among the factors affecting MGD, the highest correlation was seen between MGD and age (R = -0.85).</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2024-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141175577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cone beam CT doses in radiotherapy patient positioning in Finland-prostate treatments.","authors":"Teemu Siiskonen, Saara Alenius, Tiina Seppälä, Joonas Tikkanen, Miia Nadhum, Jarkko Ojala","doi":"10.1093/rpd/ncae133","DOIUrl":"10.1093/rpd/ncae133","url":null,"abstract":"<p><p>Imaging parameters, frequencies and resulting patient organ doses in treatments of prostate cancer were assessed in Finnish radiotherapy centres. Based on a questionnaire to the clinics, Monte Carlo method was used to estimate organ doses in International Commission on Radiological Protection standard phantom for prostate, bladder, rectum and femoral head. The results show that doses from cone beam computed tomography imaging have reduced compared to earlier studies and are between 3.6 and 34.5 mGy per image for the above-mentioned organs and for normal sized patients. There still is room for further optimization of the patient exposure, as many centres use the default imaging parameters, and the length of the imaged region may not be optimal for the purpose.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2024-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141200564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulating the head of a TrueBeam linear particle accelerator and calculating the photoneutron spectrum on the central axis of a 10-MV photon using particle and heavy-ion transport system code.","authors":"Soai Dang Quoc, Toshioh Fujibuchi, Hiroyuki Arakawa, Keisuke Hamada","doi":"10.1093/rpd/ncae124","DOIUrl":"10.1093/rpd/ncae124","url":null,"abstract":"<p><p>Photon energy is higher than the (γ,n) threshold, allowing it to interact with the nuclei of materials with high z properties and liberate fast neutrons. This represents a potentially harmful source of radiation for humans and the environment. This study validated the Monte Carlo simulation, using the particle and heavy-ion transport code system (PHITS) on a TrueBeam 10-MV linear particle accelerator's head shielding model and then used this PHITS code to simulate a photo-neutron spectrum for the transport of the beam. The results showed that, when comparing the simulated to measured PDD and crosslines, 100% of the γ-indexes were <1 (γ3%/3mm) for both simulations, for both phase-space data source and a mono energy source. Neutron spectra were recorded in all parts of the TrueBeam's head, as well as photon neutron spectra at three points on the beamline.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141065040","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of twin fetal exposure to radiofrequency field during magnetic resonance imaging.","authors":"Nan Zhong, Qunzheng Mi, Meng Lu, Haoyu Jiang, Yi Zhang","doi":"10.1093/rpd/ncae119","DOIUrl":"10.1093/rpd/ncae119","url":null,"abstract":"<p><p>Fetal development is essential to the human lifespan. As more and more multifetal gestations have been reported recently, clinical diagnosis using magnetic resonance imaging (MRI), which introduced radiofrequency (RF) exposure, raised public concerns. The present study developed two whole-body pregnant models of 31 and 32 gestational weeks (GWs) with twin fetuses and explored RF exposure by 1.5 and 3.0 T MRI. Differences in the relative position of the fetus and changes in fetal weight can cause differences in fetal peak local specific absorption rate averaged over 10 g tissue (pSAR10g). Variation of pSAR10g due to different fetal positions can be ~35%. Numerically, twin and singleton fetal pSAR10g results were not significantly different, however twin results exceeded the limit in some cases (e.g. fetuses of 31 GW at 1.5 T), which indicated the necessity for further research employing anatomically correct twin-fetal models coming from various GWs and particular sequence to be applied.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141082238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Monte Carlo simulation for photon energy response from the RADOS dosemeter.","authors":"Max da Silva Ferreira","doi":"10.1093/rpd/ncae114","DOIUrl":"10.1093/rpd/ncae114","url":null,"abstract":"<p><p>Ionizing radiation interaction models are commonly included in Monte Carlo codes. However, as there are different models and different output quantities available, it is important to understand the physical phenomena used. So, the aim of this study is to analyze the photon interaction model called Simple Physical Treatment of the Monte Carlo code MCNPX to estimate the energy dependence of photons from the RADOS dosemeter and to validate this calculation method by comparing it with experimental results found in the literature. The energy deposition in the MTS-N detector and the air kerma were obtained accompanied by their uncertainties, which varied between 1.5% and 3.0%. The RADOS dosemeter simulation and the calculation methodology applied in this study have been validated. Therefore, when using the Simple Physical Treatment model, the effective dose can be corrected by a correction factor calculated from the simulated results.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140857835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimation of 241Am and 239Pu activity embedded in the tissue using portable planar HPGe detector.","authors":"Manohari Murugan, Sugumar Ponraj, Mathiyarasu Ramasamy, Ponraju Durairaj, Venkatraman Balasubramanian","doi":"10.1093/rpd/ncae105","DOIUrl":"10.1093/rpd/ncae105","url":null,"abstract":"<p><p>This paper describes a procedure for the estimation of 241Am and 239Pu activity present in the human tissue by measuring the depth of contaminant using a portable Planar High Purity Germanium detector (HPGe). The ratios of photopeak counts of X-rays or gammas obtained with the detector coupled to collimator are calculated for the estimation of depth of the contaminant and the optimum one is determined. Since Minimum Detectable Activities (MDA) for the detector coupled to a collimator are higher than that of bare detector, activity must be estimated using bare detector, after locating the contaminant. Two methods are described for the estimation of plutonium coexisting with 241Am: (i) Abundance and isotopic correction for 239Pu (ii) and 239Pu:241Am ratio. The procedure to estimate 239Pu when plutonium isotopes alone are present is also established. An optimum monitoring period to detect the minimum value of intake for both radionuclides corresponding to chelation therapy and excision is also derived.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140867682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficacy of gonadal shielding in dose reduction for female pelvic radiography.","authors":"Saki Nozoe, Kei Terazaki, Makoto Sasaki, Manabu Nakata","doi":"10.1093/rpd/ncae116","DOIUrl":"10.1093/rpd/ncae116","url":null,"abstract":"<p><p>This study aimed to evaluate the dose reduction using gonad shielding (GS) during pelvic imaging. Three types of pelvic images (radiography, magnetic resonance and computed tomography) were fused to elucidate the three-dimensional relationship between the position of ovaries and GS. To estimate the dose received by the ovaries, the off-axis dose at any given depth was measured under two different imaging conditions using thermoluminescence dosemeters and a polymethyl methacrylate phantom. The mean ovarian depth was 8.4 cm. The mean estimated ovarian dose without an additional filter was 0.36 mGy without GS and 0.14 mGy with GS. The mean estimated ovarian dose with an additional filter was 0.24 mGy without GS and 0.10 mGy with GS. The efficacy of ovarian dose reduction should be evaluated based on the achieved ovarian dose, considering the ovarian depth and use of additional filtration, rather than the ovarian protection rate of GS.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140899381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Medical staff monitoring in interventional cardiology: over apron dosemeter placement based on measurements and simulations.","authors":"Paolo Ferrari, Giovanna Venturi, Lorenzo Campani, Francesca Mariotti, Frank Becker, Jan Jansen, Zoran Jovanović, Dragana Krstić, Pedro Teles","doi":"10.1093/rpd/ncae125","DOIUrl":"10.1093/rpd/ncae125","url":null,"abstract":"<p><p>Interventional cardiology is characterized by high radiation exposure for both the patient and the operator. Adequate shielding and monitoring of the operator are fundamental to comply with radiation protection principles. In a previous work, the effect on the dose of the dosemeter position on the chest was studied. In this paper, the investigation has been completed, employing an anthropomorphic thorax phantom, equipped with arms. Although there are differences between the Monte Carlo simulations and the measurements, similar trends are observed, showing that the reduction in dose, due to the arms, is between 20 and 60%, compared with the situation without arms. For that reason, considering a dosemeter placed on the chest, the upper position, which is the least affected by the arms, should be preferred while the extreme lateral position, near the armpit, should be avoided.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141076449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}