Health physics最新文献

{"title":"Implementation of Stochastic Gradient Descent in an Automated Glow Peak Identification Software for Multiple Thermoluminescent Dosimeter Types.","authors":"Jordan D Noey, Colin J Stewart, Wenjin Yu, Kimberlee J Kearfott","doi":"10.1097/HP.0000000000001931","DOIUrl":"10.1097/HP.0000000000001931","url":null,"abstract":"<p><strong>Abstract: </strong>A glow-curve analysis code was previously developed in C++ to analyze thermoluminescent dosimeter glow curves using automated peak detection while applying a first-order kinetics model. A newer version of this code was implemented to improve the automated peak detection and curve fitting models. The Stochastic Gradient Descent Algorithm was introduced to replace the prior approach of taking first and second-order derivatives for peak detection. Additionally, early stopping mechanisms were invoked to improve the previously used Levenberg-Marquardt Algorithm employed for curve fitting. The two software versions were compared through glow curve analysis of different thermoluminescent dosimeter materials and calculation of the corresponding figures of merit. Overall improvements were shown, namely an increase in the number of peaks detected and a reduction of the mean figure of merit by approximately 46%.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":" ","pages":"393-398"},"PeriodicalIF":1.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142947846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of Radionuclide Resuspension via Aeolian Processes at a Uranium Mill Tailings Site.","authors":"Vanessa Adriatico, Camille Palmer","doi":"10.1097/HP.0000000000001929","DOIUrl":"10.1097/HP.0000000000001929","url":null,"abstract":"<p><strong>Abstract: </strong>A former uranium recovery facility located in northwestern New Mexico currently serves as a uranium mill tailings site undergoing reclamation and decommissioning. High velocity winds are common in the area, causing soil erosion via aeolian processes. Strong winds may carry soil for several kilometers, which is redeposited downwind. This study estimates the potential for impact on remediation efforts caused by downwind contamination from soil-bound 226 Ra resuspension. The study was performed by measuring the mass of soil moving onsite to determine horizontal saltating flux over the period of 3 mo. Previous frameworks relating dimensional flux were used to estimate suspension flux from site-massed saltating flux. Using concentrations of soil-bound radionuclides and meteorological data collected onsite, a modified Gaussian plume model estimating downwind deposition of contaminants was constructed. The highest deposition rate calculated, 6.81 × 10 -15 Bq cm -2 s -1 , suggests approximately 4.3 million years of deposition are required to exceed the criterion for release, a far longer timespan than the expected remediation and release of the site in 2030. Based on the results, estimated impacts of windblown soil contamination were determined to be negligible.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":" ","pages":"385-392"},"PeriodicalIF":1.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11939084/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142947821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Clarification of Johnston Island Nuclear Tests.","authors":"Kathleen M Thiessen, Steven L Simon","doi":"10.1097/HP.0000000000001981","DOIUrl":"https://doi.org/10.1097/HP.0000000000001981","url":null,"abstract":"<p><strong>Abstract: </strong>US nuclear weapons launched from Johnston Island for testing purposes in 1958 and 1962 resulted in 12 successful launches, from which high-altitude nuclear detonations occurred, and four failed launches, resulting in aborted tests with no nuclear detonations. Lists of US nuclear tests produced by testing organizations include only events in which nuclear detonations occurred. Hence, the four failed launches in which no nuclear detonation occurred were not considered tests and are not in the lists, even though three of the failed launches resulted in significant local contamination of Johnston Island. A few summaries of nuclear testing at Johnston Island have mistakenly assumed that the launches resulting in local contamination were among the 12 nuclear tests listed for Johnston Island. This note explicitly lists the identities of all 16 launches of nuclear devices from Johnston Island for the purpose of correcting this assumption.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144017353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electret Production and Applications with Special Regard to Health Physics Dosimetry: A Review.","authors":"Mehdi Sohrabi, Sahel Rabiee","doi":"10.1097/HP.0000000000001896","DOIUrl":"10.1097/HP.0000000000001896","url":null,"abstract":"<p><strong>Abstract: </strong>An electret detector is a piece of dielectric material film charged or polarized by a specific charging method to induce a quasi-permanent electric field. Electret films perform unique characteristics for production and applications in many areas of science and technology, especially in health physics dosimetry. A charged electret detector, when placed in an ionized environment, collects negative or positive ions depending on its original charging state, which reduces its original charge. The number of charges reduced in the ionized field is usually proportional to the absorbed radiation dose. In this paper, the state-of-the-art information on the type of electrets, production methods, some applications in particular in health physics dosimetry, and relevant concepts are reviewed.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":" ","pages":"320-331"},"PeriodicalIF":1.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142727888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cosmic Radiation Exposure: A Review of Recent Research on the Incidence and Prevention of Cancer in Aircrews.","authors":"Lisa D Eckhardt","doi":"10.1097/HP.0000000000001894","DOIUrl":"10.1097/HP.0000000000001894","url":null,"abstract":"<p><strong>Abstract: </strong>The author provides a literature review examining the clinical risks of cosmic radiation exposure and incidence of cancer in aircrews including pilots, flight attendants, and flight engineers or navigators. The review focuses on ionizing radiation exposure in aircrews as an occupational working group. The author will discuss the types of cancer associated with cosmic ionizing radiation exposure and the prevalence of certain cancer types noted in this population. Monitoring of ionizing radiation of aircrews in the United States is not required in 2024, which makes assessing exposure a challenge. The author also discusses associated risk factors and prevention strategies in aircrews. United States aircrews are an occupational group with known elevated exposure to ionizing radiation from natural cosmic sources, which has been linked to health risks, particularly for cancer. This occupational group is not monitored in 2024 and would benefit from occupational exams for medical surveillance and hazard awareness.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":"128 4","pages":"291-297"},"PeriodicalIF":1.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143500684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Waveforms of 4G and 5G Radiofrequency Signals: Are Differences Relevant to Biology or Health?","authors":"Kenneth R Foster, David Maxson, Peter M Zollman","doi":"10.1097/HP.0000000000001895","DOIUrl":"10.1097/HP.0000000000001895","url":null,"abstract":"<p><strong>Abstract: </strong>This Note briefly reviews, at a level that is intended to be accessible to non-specialists, the similarities and differences between waveforms of 4G Long-Term Evolution (4G LTE) and 5G New Radio (5G NR) transmitted by cellular base stations, as a resource for health physicists and others who are engaged in public communication about cellular telephone technologies. Despite the difference in levels of controversy presently existing between 4G LTE (introduced in 2008) and 5G NR (introduced in 2019), the differences in waveform as represented by the baseband waveform are minimal, although 5G NR offers system designers a much wider choice of parameters. Transmitted radiofrequency signals in both technologies appear noise-like, in a frequency range that is narrowly contained in the assigned channel. It is concluded that the modulation differences between 4G LTE and 5G NR are unlikely to have any biological relevance, but the greater range of accessible frequencies in 5G NR suggests the need for further health research, particularly in the 5G FR2 millimeter-wave band.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":"128 4","pages":"332-336"},"PeriodicalIF":1.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143500630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ionizing Radiation Dose to the Skin Assessed after Rapid Detection of 232 Th in Consumer Products.","authors":"Christine Karbiwnyk, Philip Stafford, Elon Malkin, Kelly Garnick, Thomas A Scott, Cong Wei","doi":"10.1097/HP.0000000000001891","DOIUrl":"10.1097/HP.0000000000001891","url":null,"abstract":"<p><strong>Abstract: </strong>After some consumer products indicated elevated levels of 232 Th progeny by gamma-ray spectrometry, a microwave digestion and inductively coupled plasma-mass spectrometry (ICP-MS) procedure was implemented for the direct assay of 232 Th content to ensure compliance with Federal regulations and guidelines. Levels of 232 Th were determined by ICP-MS based on standard calibration using a 205 Tl internal standard. The method had a method detection limit (MDL) of 0.15 Bq g -1 and a lower limit of quantification (LLOQ) of 0.65 Bq g -1 for 232 Th, making it a suitable confirmatory method following gamma-ray spectrometry. The 232 Th activity concentration calculated from the ICP-MS results ranged from 2.0-3.4 Bq g -1 for the kinesiology tape samples and 20 Bq g -1 for the silicone ion bracelet. The VARSKIN+1.0 software program was used to calculate the shallow dose equivalent of ionizing radiation from 232 Th and its progeny from the ICP-MS results. The skin dose to the consumer wearing the kinesiology tape ranged from 0.48-1.6 mSv y -1 . The skin dose to the consumer with constant wear of the silicone ion bracelet was estimated to be 17 mSv y -1 . Although 232 Th may be determined indirectly by assay of high abundance gamma rays produced by its progeny, the US Code of Federal Regulations (CFR) requires the direct assay of 232 Th for confirmatory analysis. We found this ICP-MS method to be a rapid 232 Th confirmatory technique compared to a chemical separation followed by alpha spectrometry procedure.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":" ","pages":"279-285"},"PeriodicalIF":1.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142604381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultra-low to Moderate Radiation Level Neutron Dosimetry Measurements with H*10-TMFD vs. ROSPEC, Eberline, and Ludlum Detector Systems.","authors":"Stepan Ozerov, Nathan Boyle, Catalin Harabagiu, David DiPrete, Tad Whiteside, Alan Boone, William Noll, Rusi P Taleyarkhan","doi":"10.1097/HP.0000000000001907","DOIUrl":"10.1097/HP.0000000000001907","url":null,"abstract":"<p><strong>Abstract: </strong>H*10 neutron dosimetry (unlike gamma dosimetry), requires consideration of neutron energy spectra due to the 20× variation of the weight factor over the thermal-to-fast energy range, as well as the neutron radiation field dose rates ranging from cosmic, ~.01 μSv h -1 levels to commonly encountered ~10-200 μSv h -1 in nuclear laboratories/processing plants, and upwards of 10 4 Sv h -1 in nuclear reactor environments. This paper discusses the outcome of the comparison of spectrum-weighted neutron dosimetry covering thermal-to-fast energy using the novel H*-TMFD spectroscopy-enabled sensor system in comparison with measurements using state-of-the-art neutron dosimetry systems at SRNS-Rotating Spectrometer (ROSPEC), and non-spectroscopic Eberline ASP2E (\"Eberline\") and Ludlum 42-49B (\"Ludlum\") survey instrumentation. The H*-TMFD was validated for gamma blindness using a 2.48×10 10 Bq 137 Cs source. The background dose rate in Savannah River Nuclear Solutions' (SRNS) low-scatter facility with all neutron sources withdrawn was estimated at 0.005 μSv h -1 . From moderately high radiation field tests conducted with the high intensity (1.4 × 10 9 n s -1 ) 252 Cf source and a total data collection time of ~0.15 h, the predicted dose rates from Eberline (non-spectroscopic), Ludlum (non-spectroscopic), and spectroscopic H*-TMFD instruments were found to be: ~170 μSv h -1 , ~200 μSv h - , and ~ 120 μSv h -1 , respectively. The equivalent spectroscopic (SRNS measured) H*10 dose rate from ROSPEC value is 130 μSv h -1 , within 10% of H*10-TMFD measurement. Tests conducted for ultra-low intensity radiation field used a ~ 1.6 × 10 3 n s -1 252 Cf bare neutron source for which over a collection time of ~18 h, the Eberline meter measured an instantaneous dose/count rate of 0 μSv h -1 and a pulse-integrated dose rate of 0.034 μSv h -1 at ~1 m. In contrast, the H*-TMFD panel located 0.22 m in direct line of sight of the 252 Cf source spectroscopically measured ~0.4 μSv h -1 (within +/- 5%) over 1.8 h collection live time-with which spectrum matched perfectly to that of a bare 252 Cf source. The H*TMFD predicted value of ~0.4 μSv h -1 was cross-checked and found to be within 10% of LLNL's published value of ~0.37 μSv h -1 (intensity/distance corrected via 1/r 2 law of 25.5 μSv h -1 at 1 m for a 1 μg 252 Cf source); as well as from use of ICRP 74 conversion coefficients and MCNP code simulations. As expected, for a bare 252 Cf source, H*TMFD measured epithermal neutron energy-related dose rates are well below 1% of the total dose rates. For ~0.01 μSv h -1 neutron radiation fields, ROSPEC measurements for H*10 dose rates are estimated to take 7+ d, vs. under 2 h with the H*TMFD. The feasibility of using a single CTMFD in survey mode for H*10 dose rate (nSv h - to μSv h -1 ) measurements within 2-3 min is demonstrated.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":" ","pages":"298-319"},"PeriodicalIF":1.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143058814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dosimetry Testing for a New In Vivo X-ray Fluorescence Measurement System.","authors":"Chandler J Burgos, Daniel E Read, Thomas R Grier, Maruf Khan, Marc G Weisskopf, Kathryn M Taylor, Aaron J Specht","doi":"10.1097/HP.0000000000001839","DOIUrl":"10.1097/HP.0000000000001839","url":null,"abstract":"<p><strong>Abstract: </strong>Lead exposure poses severe health risks to individuals, impacting cognitive function, growth, learning, and behavior. Current lead detection methods, primarily blood testing and x-ray fluorescence (XRF) of bone, have limitations. This study introduces a novel in vivo XRF measurement system using K-shell energies of lead, addressing limitations of previous methods. The study aimed to characterize beam directionality, subject radiation dose, and operator occupational exposure. Using a high-energy x-ray tube and room-temperature detectors, various parameters were assessed with bone and tissue phantoms. Dose measurements were taken by altering voltage, current, and shielding. Scatter and spatial measurements highlighted increased scatter with bone and tissue presence, emphasizing the safest positions for bystanders and operators. Results exhibited expected dose rate changes with varying parameters, showcasing the impact of bone and tissue on scatter radiation. The system's total body effective dose (with an 8-mm molybdenum shielding indicating minimal risk compared to established public dose limits) for an adult was 1.94 μSv; for a child aged 10 y, it was 3.28 μSv. This system demonstrates promising capabilities for lead exposure monitoring, offering negligible occupational exposure and minimal risk to individuals being scanned. Its safety and efficacy position it as a valuable tool in assessing lead exposure, potentially improving preventive measures.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":"128 4","pages":"273-278"},"PeriodicalIF":1.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11864586/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143500685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lutetium-177 Therapy in Italy: Environmental Impact Assessment in Anticipation of Its Widespread Use in Prostate Cancer Treatment.","authors":"Anna Brusa, Fabrizio Campi, Claudia Cavatorta, Alessandro Antonio Porta, Sofia Viganò","doi":"10.1097/HP.0000000000001893","DOIUrl":"10.1097/HP.0000000000001893","url":null,"abstract":"<p><strong>Abstract: </strong>This article addresses the evolving state of lutetium-177 radiopharmaceutical therapies in Italy, focusing on the importance of the definition of patient management practices regarding the approved treatments based on [ 177 Lu]Lu-DOTATATE for neuroendocrine tumors and [ 177 Lu]Lu-PSMA-617 for metastatic castration-resistant prostate cancer. Italian medical facilities are facing new challenges with the increase in the demand for such therapies while transitioning from restrictive hospitalization requirements to more flexible outpatient options. Therefore, four management strategies are described here, varying from immediate discharge after the administration to 24-h hospitalization, and their environmental and radiation safety implications are evaluated through simple models aimed at assessing the effective doses on the local population and wastewater purification plant workers. Results show that, while higher effective doses may be caused by an immediate discharge-based modality, they remain within acceptable limits, particularly when dealing with a smaller number of patients. Prolonged hospitalizations guarantee superior radiation safety levels but might not be sustainable with the expected increase in patient volumes in the future.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":" ","pages":"286-290"},"PeriodicalIF":1.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142345586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}