scholarly journals Meeting radiation dosimetry capacity requirements of population-scale exposures by geostatistical sampling

2020 ◽  
Author(s):  
Peter K. Rogan ◽  
Eliseos J. Mucaki ◽  
Ruipeng Lu ◽  
Ben C. Shirley ◽  
Edward Waller ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Radiation Exposure ◽  
Large Scale ◽  
Large Population ◽  
First Responders ◽  
Weather Conditions ◽  
Small Population ◽  
Geostatistical Analysis ◽  
Overlapping Grids ◽  
Population Scale

AbstractBackgroundAccurate radiation dose estimates are critical for determining eligibility for therapies by timely triaging of exposed individuals after large-scale radiation events. However, the universal assessment of a large population subjected to a nuclear spill incident or detonation is not feasible. Even with high-throughput dosimetry analysis, test volumes far exceed the capacities of first responders to measure radiation exposures directly, or to acquire and process samples for follow-on biodosimetry testing.AimTo significantly reduce data acquisition and processing requirements for triaging of treatment-eligible exposures in population-scale radiation incidents.MethodsPhysical radiation plumes modelled nuclear detonation scenarios of simulated exposures at 22 US locations. Models assumed only location of the epicenter and historical, prevailing wind directions/speeds. The spatial boundaries of graduated radiation exposures were determined by targeted, multistep geostatistical analysis of small population samples. Initially, locations proximate to these sites were randomly sampled (generally 0.1% of population). Empirical Bayesian kriging established radiation dose contour levels circumscribing these sites. Densification of each plume identified critical locations for additional sampling. After repeated kriging and densification, overlapping grids between each pair of contours of successive plumes were compared based on their diagonal Bray-Curtis distances and root-mean-square deviations, which provided criteria (<10% difference) to discontinue sampling.Results/ConclusionsWe modeled 30 scenarios, including 22 urban/high-density and 2 rural/low-density scenarios under various weather conditions. Multiple (3-10) rounds of sampling and kriging were required for the dosimetry maps to converge, requiring between 58 and 347 samples for different scenarios. On average, 70±10% of locations where populations are expected to receive an exposure ≥2Gy were identified. Under sub-optimal sampling conditions, the number of iterations and samples were increased and accuracy was reduced. Geostatistical mapping limits the number of required dose assessments, the time required, and radiation exposure to first responders. Geostatistical analysis will expedite triaging of acute radiation exposure in population-scale nuclear events.

The Psychosocial Aftermath of the Chernobyl Disaster in an Area of Relatively Low Contamination

1997 ◽  
Vol 12 (1) ◽  
pp. 41-46 ◽  
Author(s):  
Victor S. Koscheyev ◽  
Gloria R. Leon ◽  
Andrej V. Gourine ◽  
Valerie N. Gourine
Keyword(s):  
Radiation Exposure ◽  
Health Effects ◽  
Large Scale ◽  
Large Population ◽  
Family Members ◽  
Physical Symptoms ◽  
Government Information ◽  
Chernobyl Disaster ◽  
The Impact

AbstractIntroduction:There has been relatively little attention paid to the mid- and long-term effects of large-scale disasters, particularly their effects on children and young people. At the present time, the impact of the Chernobyl catastrophe on the daily lives of the affected population may include one of strong psychological stress due to uncertainty about ultimate health outcomes. Persons in the Chernobyl region in specific areas of low contamination may be affected similarly. This investigation assesses radiation concerns and attitudes about health and government information, nine years after the disaster, in a group of adults and adolescents residing in a relatively uncontaminated village in the Chernobyl area.Methods:Questionnaires were administered to 94 adults and 50 adolescents. Items assessed beliefs about extent of radiation exposure, health concerns regarding oneself and family members, past and current pre-occupation about the disaster, and trust in the accuracy of government information about health effects.Results:Considerable uncertainty was demonstrated in both adults and adolescents about the extent of their and their families exposure to radiation. Marked distrust of past and current government information about health effects was evident. A large proportion of subjects reported that they still thought frequently about the Chernobyl accident. They worried about health problems related to radiation exposure whenever they or their family members exhibited physical symptoms or complaints, and they urged family members to go to a medical clinic for evaluation to assess these symptoms.Conclusion:The extent of long-term concerns about the personal and family health effects of the Chernobyl disaster in this population residing in a relatively uncontaminated village is striking: the psychological impact on adolescents is considerable. The stress generated is maintained by the realistic uncertainty about the ultimate health consequences to the overall population as a result of radiation exposure and distrust in government information about contamination levels in this particular village. The level of stress and its effects on physical and mental health may increase over time if there is a rise in morbidity in the area. The continuing health needs of the extremely large population affected by the Chernobyl disaster need to be addressed.

EVALUATION OF OCCUPATIONAL RADIATION EXPOSURE IN A RADIO-DIAGNOSTIC FACILITY IN KATSINA- NIGERIA

2020 ◽  
Vol 4 (2) ◽  
pp. 722-729
Author(s):  
Usman Sani ◽  
Bashir Gide Muhammad ◽  
Dimas Skam Joseph ◽  
D. Z. Joseph
Keyword(s):  
Radiation Dose ◽  
Radiation Exposure ◽  
Short Exposure ◽  
Skin Dose ◽  
Continuous Training ◽  
Short Exposure Time ◽  
Occupational Dose ◽  
Dose Limits ◽  
Radiation Workers ◽  
Occupational Radiation

Poor implementation of quality assurance programs in the radiation industry has been a major setback in our locality. Several studies revealed that occupational workers are exposed to many potential hazards of ionizing radiation during radio-diagnostic procedures, yet radiation workers are often not monitored. This study aims to evaluate the occupational exposure of the radiation workers in Federal Medical Centre Katsina, and to compare the exposure with recommended occupational radiation dose limits. The quarterly readings of 20 thermo-luminescent dosimeters (TLDs') used by the radiation workers from January to December, 2019 were collected from the facility's radiation monitoring archive, and subsequently assessed and analyzed. The results indicate that the average annual equivalent dose per occupational worker range from 0.74 to 1.20 mSv and 1.28 to 2.21 mSv for skin surface and deep skin dose, measured at 10 mm and 0.07 mm tissue depth respectively. The occupational dose was within the recommended national and international limits of 5 mSv per annum or an average of 20 mSv in 5 years. Therefore, there was no significant radiation exposure to all the occupational workers in the study area. Though, the occupational radiation dose is within recommended limit, this does not eliminate stochastic effect of radiation. The study recommended that the occupational workers should adhere and strictly comply with the principles of radiation protection which includes distance, short exposure time, shielding and proper monitoring of dose limits. Furthermore, continuous training of the radiation workers is advised.

scholarly journals Automated Cytogenetic Biodosimetry at Population-Scale

Radiation ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 79-94
Author(s):  
Peter K. Rogan ◽  
Eliseos J. Mucaki ◽  
Ben C. Shirley ◽  
Yanxin Li ◽  
Ruth C. Wilkins ◽  
...  
Keyword(s):  
High Performance ◽  
Large Scale ◽  
Dicentric Chromosome ◽  
Automated Assignment ◽  
Simulated Population ◽  
Dose Estimation ◽  
Processing Times ◽  
Multiple Processors ◽  
Exposure Levels ◽  
Population Scale

The dicentric chromosome (DC) assay accurately quantifies exposure to radiation; however, manual and semi-automated assignment of DCs has limited its use for a potential large-scale radiation incident. The Automated Dicentric Chromosome Identifier and Dose Estimator (ADCI) software automates unattended DC detection and determines radiation exposures, fulfilling IAEA criteria for triage biodosimetry. This study evaluates the throughput of high-performance ADCI (ADCI-HT) to stratify exposures of populations in 15 simulated population scale radiation exposures. ADCI-HT streamlines dose estimation using a supercomputer by optimal hierarchical scheduling of DC detection for varying numbers of samples and metaphase cell images in parallel on multiple processors. We evaluated processing times and accuracy of estimated exposures across census-defined populations. Image processing of 1744 samples on 16,384 CPUs required 1 h 11 min 23 s and radiation dose estimation based on DC frequencies required 32 sec. Processing of 40,000 samples at 10 exposures from five laboratories required 25 h and met IAEA criteria (dose estimates were within 0.5 Gy; median = 0.07). Geostatistically interpolated radiation exposure contours of simulated nuclear incidents were defined by samples exposed to clinically relevant exposure levels (1 and 2 Gy). Analysis of all exposed individuals with ADCI-HT required 0.6–7.4 days, depending on the population density of the simulation.

scholarly journals Radiation Dose Reduction in CT Torsion Measurement of the Lower Limb: Introduction of a New Ultra-Low Dose Protocol

Diagnostics ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1209
Author(s):  
Gabriel Keller ◽  
Simon Götz ◽  
Mareen Sarah Kraus ◽  
Leonard Grünwald ◽  
Fabian Springer ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Radiation Exposure ◽  
Lower Limb ◽  
Low Dose ◽  
Body Volume ◽  
Reconstruction Algorithms ◽  
Pelvic Radiograph ◽  
Lower Radiation Dose ◽  
Median Total Dose ◽  
Image Reconstruction Algorithms

This study analyzed the radiation exposure of a new ultra-low dose (ULD) protocol compared to a high-quality (HQ) protocol for CT-torsion measurement of the lower limb. The analyzed patients (n = 60) were examined in the period March to October 2019. In total, 30 consecutive patients were examined with the HQ and 30 consecutive patients with the new ULD protocol comprising automatic tube voltage selection, automatic exposure control, and iterative image reconstruction algorithms. Radiation dose parameters as well as the contrast-to-noise ratio (CNR) and diagnostic confidence (DC; rated by two radiologists) were analyzed and potential predictor variables, such as body mass index and body volume, were assessed. The new ULD protocol resulted in significantly lower radiation dose parameters, with a reduction of the median total dose equivalent to 0.17 mSv in the ULD protocol compared to 4.37 mSv in the HQ protocol (p < 0.001). Both groups showed no significant differences in regard to other parameters (p = 0.344–0.923). CNR was 12.2% lower using the new ULD protocol (p = 0.033). DC was rated best by both readers in every HQ CT and in every ULD CT. The new ULD protocol for CT-torsion measurement of the lower limb resulted in a 96% decrease of radiation exposure down to the level of a single pelvic radiograph while maintaining good image quality.

scholarly journals Performance of Strawberry Varieties Developed for Perennial Matted-Row Production in Annual Plasticulture in a Cold Climate Region

Agronomy ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1407
Author(s):  
Courtney A. Weber
Keyword(s):  
Large Scale ◽  
Fruit Size ◽  
Weather Conditions ◽  
Cold Climate ◽  
Annual Production ◽  
High Yield ◽  
Production Cycle ◽  
Late Season ◽  
Berry Weight ◽  
High Yields

Annual plasticulture production of strawberries promises superior weed control, fruit quality and yields. However, strawberry varieties adapted for perennial, matted-row production and local markets in cold climate regions have not been widely tested for adaptation to an annual production cycle. Productivity of seven short-day varieties developed for matted-row and/or annual production was examined in an annual plasticulture system in two consecutive trials in central NY (lat. 42.87° N, long. 76.99° W) harvested in 2013 and 2014. ‘Flavorfest’ demonstrated good performance in Trial 1 with high yield (390 g/plant) and large fruit size (13.9 g mean berry weight). ‘Jewel’ was shown to be well adapted to the annual plasticulture system with consistently high yields (330 and 390 g/plant) that equaled or surpassed other varieties and had moderate fruit size. ‘Chandler’ performed similarly to previous trials conducted in warmer regions with yield (340 g/plant) and fruit size (9.8 g mean berry weight) similar to ‘Jewel’. ‘Clancy’ yielded less but was consistent from year to year. The late season varieties Seneca and Ovation showed marked variability between years, possibly due to drastically different temperatures during flowering and fruit development in Trial 1 compared to Trial 2. High temperatures in Trial 1 likely caused higher early fruit yield, a compressed season and a precipitous decline in fruit size in the later season, thus reducing yield in the late season. Survival after a second dormant period was poor resulting in a small second harvest and reduced fruit size. Overall, the system demonstrated many of the expected benefits but may be more sensitive to weather conditions in the region. While many varieties developed for matted-row production may work well in an annual plasticulture system, not all varieties are equally adapted. Performance of each variety should be determined independently before large scale adoption by growers.

scholarly journals A High-Speed, Light-Weight Scalar Magnetometer Bird for km Scale UAV Magnetic Surveying: On Sensor Choice, Bird Design, and Quality of Output Data

2021 ◽  
Vol 13 (4) ◽  
pp. 649
Author(s):  
Arne Døssing ◽  
Eduardo Lima Simoes da Silva ◽  
Guillaume Martelet ◽  
Thorkild Maack Rasmussen ◽  
Eric Gloaguen ◽  
...  
Keyword(s):  
High Speed ◽  
Large Scale ◽  
Signal To Noise Ratio ◽  
Regional Scale ◽  
Weather Conditions ◽  
Light Weight ◽  
Output Data ◽  
Efficient Manner ◽  
Flexible System ◽  
Scalar Data

Magnetic surveying is a widely used and cost-efficient remote sensing method for the detection of subsurface structures at all scales. Traditionally, magnetic surveying has been conducted as ground or airborne surveys, which are cheap and provide large-scale consistent data coverage, respectively. However, ground surveys are often incomplete and slow, whereas airborne surveys suffer from being inflexible, expensive and characterized by a reduced signal-to-noise ratio, due to increased sensor-to-source distance. With the rise of reliable and affordable survey-grade Unmanned Aerial Vehicles (UAVs), and the developments of light-weight magnetometers, the shortcomings of traditional magnetic surveying systems may be bypassed by a carefully designed UAV-borne magnetometer system. Here, we present a study on the development and testing of a light-weight scalar field UAV-integrated magnetometer bird system (the CMAGTRES-S100). The idea behind the CMAGTRES-S100 is the need for a high-speed and flexible system that is easily transported in the field without a car, deployable in most terrain and weather conditions, and provides high-quality scalar data in an operationally efficient manner and at ranges comparable to sub-regional scale helicopter-borne magnetic surveys. We discuss various steps in the development, including (i) choice of sensor based on sensor specifications and sensor stability tests, (ii) design considerations of the bird, (iii) operational efficiency and flexibility and (iv) output data quality. The current CMAGTRES-S100 system weighs ∼5.9 kg (including the UAV) and has an optimal surveying speed of 50 km/h. The system was tested along a complex coastal setting in Brittany, France, targeting mafic dykes and fault contacts with magnetite infill and magnetite nuggets (skarns). A 2.0 × 0.3 km area was mapped with a 10 m line-spacing by four sub-surveys (due to regulatory restrictions). The sub-surveys were completed in 3.5 h, including >2 h for remobilisation and the safety clearance of the area. A noise-level of ±0.02 nT was obtained and several of the key geological structures were mapped by the system.

scholarly journals Radiation dose from common radiological investigations and cumulative exposure in children with cystic fibrosis: an observational study from a single UK centre

BMJ Open ◽  
2017 ◽  
Vol 7 (8) ◽  
pp. e017548 ◽  
Author(s):  
Rebecca Ward ◽  
William D Carroll ◽  
Paula Cunningham ◽  
Sheng-Ang Ho ◽  
Mary Jones ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Radiation Dose ◽  
Radiation Exposure ◽  
Cumulative Exposure ◽  
X Rays ◽  
Modern Equipment ◽  
Increased Risk ◽  
Risk Of Malignancy ◽  
The Mean ◽  
Cumulative Radiation Exposure

ObjectivesCumulative radiation exposure is associated with increased risk of malignancy. This is important in cystic fibrosis (CF) as frequent imaging is required to monitor disease progression and diagnose complications. Previous estimates of cumulative radiation are outdated as the imaging was performed on older equipment likely to deliver higher radiation. Our objectives were to determine the radiation dose delivered to children during common radiological investigations using modern equipment and to identify the number of such investigations performed in a cohort of children with CF to calculate their cumulative radiation exposure.Design, setting and participantsData including age at investigation and radiation exposure measured as estimated effective dose (EED) were collected on 2827 radiological studies performed on children at one UK paediatric centre. These were combined with the details of all radiological investigations performed on 65 children with CF attending the same centre to enable calculation of each child’s cumulative radiation exposure.ResultsThe mean EED for the common radiological investigations varied according to age. The range was 0.01–0.02 mSv for chest X-rays, 0.03–0.11 mSv for abdominal X-rays, 0.57–1.69 mSv for CT chest, 2.9–3.9 mSv for abdominal and pelvic CT, 0.20–0.21 mSv for sinus CT and 0.15–0.52 mSv for fluoroscopy-guided procedures. The mean EED was three to five times higher for helical compared with axial chest CT scans. The mean annual cumulative EED for our cohort of children with CF was 0.15 mSv/year with an estimated cumulative paediatric lifetime EED (0–18 years) of 3.5 mSv.ConclusionsThis study provides up-to-date estimations of the radiation exposure when using common radiological investigations. These doses and the estimates of cumulative radiation exposure in children with CF are lower than previously reported. This reflects the reduced EED associated with modern equipment and the use of age-specific scanning protocols.

Design and Testing of ITER TF Coil Insulations

2011 ◽  
Vol 21 (3) ◽  
pp. 3127-3131 ◽  
Author(s):  
Matthew W. Hooker ◽  
Jennifer K. Walsh ◽  
Mark W. Haynes ◽  
Naseem A. Munshi
Keyword(s):  
Radiation Exposure ◽  
Large Scale ◽  
Mechanical Performance ◽  
International Organization ◽  
Vacuum Impregnation ◽  
Test Results ◽  
Qualification Test ◽  
Insulation System ◽  
Cyanate Ester Resin ◽  
Design And Testing

The design of the ITER Toroidal Field (TF) coils requires an insulation system that is amenable to the very large scale vacuum impregnation processes planned for the construction of these devices, and that will provide reliable electro-mechanical performance after radiation exposure. To address this need, CTD has developed an epoxy/cyanate ester resin system designated CTD-425. This material meets the processing requirements for use in the TF coils, and cyclic mechanical testing of conductor assemblies has demonstrated its electro-mechanical strength after 60,000 mechanical cycles. In addition, this product recently passed radiation exposure tests coordinated by the ITER International Organization and is now qualified for use in constructing the TF coils. This paper summarizes the performance characterization and qualification test results for this insulation.

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