Hardware algorithm design and validation for nuclear radiation imaging based on Monte Carlo simulation.

The nuclear radiation imaging technology, aimed at illustrating the position and distribution of radioactive sources, has undergone extensive research. By relying on a simulated radiation imaging system for data acquisition, we can significantly expedite the development cycle of these imaging instruments. Establishing simulated experimental scenarios and radiation imaging systems is of paramount significance in obtaining output signals for algorithmic testing and validation. This study is divided into two parts: simulation and hardware algorithm. In the simulation part, precise simulation of scintillation light transport in a crystal was achieved using the GEANT4 Monte Carlo simulation toolkit. A LaBr3(Ce) detector system was simulated by digitizing photon interactions. In the hardware algorithm part, a positioning algorithm based on a fully connected neural network was implemented and optimized using a heterogeneous distributed storage approach. The system validated and assessed the FPGA-based neural network gamma camera positioning algorithm, demonstrating significant consistency with computer-generated images in capturing the shape and dispersion of radioactive sources (planar, multi-point, and ring-shaped).

A novel transformer-based method for predicting air absorbed dose rates in nuclear radiation environmental monitoring.

Many studies have used various methods to estimate future nuclear radiation levels to control radiation contamination, provide early warnings, and protect public health and the environment. However, due to the high uncertainty and complexity of nuclear radiation data, existing prediction methods face the challenges of low prediction accuracy and short warning time. Therefore, accurate prediction of nuclear radiation levels is essential to safeguard human health and safety. This study proposes a novel Mixformer model to predict future hourly nuclear radiation data. The seasonality and trend of nuclear radiation data are extracted by data decomposition. To address the slow speed problem common in traditional methods for long-time series prediction tasks, Mixformer simplifies the decoder with convolutional layers to speed up the convergence of the model. The experiments consider the air-absorbed dose rate of nuclear radiation data, spectral data, six climatic conditions, and two other conditions. We use MSE and MAE metrics to verify the effectiveness of Mixformer prediction. The results show that the Mixformer proposed in this paper has better prediction performance compared to the currently popular models. Therefore, the proposed model is a feasible method for industrial nuclear radiation data processing and prediction.

Changes in body-related indices in people exposed to long-term low-dose nuclear radiation / 中国辐射卫生

@#<b>Objective</b> To investigate the effects of low-dose nuclear radiation exposure on the body by analyzing the antioxidant indices, immune indices, lymphocyte proliferation activity, and blood biochemical indices of persons exposed to long-term low-dose nuclear radiation, and to provide a basis for radiation protection and occupational health monitoring. <b>Methods</b> Eighty nuclear radiation workers were selected as the exposure group, and another 30 non-exposure personnel were selected as the control group. In both groups, blood biochemistry, serum total antioxidant capacity (T-AOC), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), lymphocyte proliferation activity, proliferating cell nuclear antigen (PCNA), apoptosis factors Bcl-2 and Bax, lymphocyte transformation rate, and lymphocyte micronucleus rate were measured. <b>Results</b> Compared with the control group, T-AOC, GSH-Px, SOD, cell proliferation activity, PCNA, Bcl-2, lymphocyte transformation rate, white blood cell count, and platelet count in the exposure group were significantly decreased, while MDA and Bax were significantly increased (<i>P</i> < 0.05). The lymphocyte micronucleus rate showed no significant difference between the two groups (<i>P</i> > 0.05). <b>Conclusion</b> Long-term low-dose exposure to nuclear radiation has certain effects on related indices of workers, but does not cause significant damage. The personnel exposed to nuclear radiation should enhance the awareness of protection and strengthen scientific protection to reduce radiation damage.

Plant-microorganism-soil interaction under long-term low-dose ionizing radiation.

As the environmental nuclear radiation pollution caused by nuclear-contaminated water discharge and other factors intensifies, more plant-microorganism-soil systems will be under long-term low-dose ionizing radiation (LLR). However, the regulatory mechanisms of the plant-microorganism-soil system under LLR are still unclear. In this study, we study a system that has been stably exposed to low-dose ionizing radiation for 10 years and investigate the response of the plant-microorganism-soil system to LLR based on the decay of the absorbed dose rate with distance. The results show that LLR affects the carbon and nitrogen migration process between plant-microorganism-soil through the "symbiotic microbial effect." The increase in the intensity of ionizing radiation led to a significant increase in the relative abundance of symbiotic fungi, such as Ectomycorrhizal fungi and Rhizobiales, which is accompanied by a significant increase in soil lignin peroxidase (LiP) activity, the C/N ratio, and C%. Meanwhile, enhanced radiation intensity causes adaptive changes in the plant functional traits. This study demonstrates that the "symbiotic microbial effect" of plant-microorganism-soil systems is an important process in terrestrial ecosystems in response to LLR.

Comparison of Standard Training to Virtual Reality Training in Nuclear Radiation Emergency Medical Rescue Education.

OBJECTIVE: Due to the particularity of nuclear radiation emergencies, professional technical training is necessary. However, nuclear radiation emergency medical rescue nurses are not well prepared to respond in time. This study aims to explore the effect of virtual reality (VR) in training nurses for nuclear radiation emergency medical rescue. METHODS: Thirty nurses who received traditional nuclear radiation rescue training from May 2020 to October 2020 were selected as the control group, and another 30 nurses who received VR nuclear radiation emergency medical rescue training from November 2020 to April 2021 were selected as the experimental group. The examination results, learning enthusiasm, training effect evaluation, and training satisfaction were compared between the 2 groups. RESULTS: The experimental group had significantly higher examination score, learning enthusiasm, training effect evaluation, and training satisfaction than the control group (P < 0.05). CONCLUSIONS: The application of VR in the training of nuclear radiation emergency medical rescue can improve the training performance, learning enthusiasm, training effect, and training satisfaction of trainees. Considering the advantages of VR, it could be widely used in the training of nuclear radiation emergency medical rescue in the future.

Development of PHITS graphical user interface for simulation of positron emitting radioisotopes production in common biological materials during proton therapy.

The Monte Carlo (MC) method is a powerful tool for modeling nuclear radiation interaction with matter. A variety of MC software packages has been developed, especially for applications in radiation therapy. Most widely used MC packages require users to write their own input scripts for their systems, which can be a time consuming and error prone process and requires extensive user experience. In the present work, we have developed a graphical user interface (GUI) bundled with a custom-made 3D OpenGL visualizer for PHITS MC package. The current version focuses on modeling proton induced positron emitting radioisotopes, which in turn can be used for verification of proton ranges in proton therapy. The developed GUI program does not require extensive user experience. The present open-source program is distributed under GPLv3 license that allows users to freely download, modify, recompile and redistribute the program.

Educational dialogue on public perception of nuclear radiation.

PURPOSE: Across the world, nuclear radiation and its effects on the population has been the topic of back-burner debates, given the strong emotional connotations involved. We believe that education is crucial for people to make informed decisions regarding nuclear energy. With a science-technology-society (STS) approach, a seminar-style educational module on Radiation and Society was formulated at Tembusu College, National University of Singapore (NUS) in 2015. This primarily aimed to equip students with the necessary analytical tools to assess evidence and thus, evaluate existing assumptions on radiation/nuclear power/nuclear energy, the effects on mankind and societal perception of radiation. METHODS: Radiation and Society was a seminar-style module which consisted of weekly 3-hour interactive sessions for 13 weeks. Throughout the semester, students were acquainted with themes and concepts related to radiation and society, such as the historical dimensions, radiation science, role in medicine, the psychology of radiation fear, existing radiation myths, complexities in radiation disaster response, communication of risks and emergency preparedness. Discussions during the sessions covered a variety of topics, including ionizing radiation as a result of nuclear fall-out, historical contextualization of nuclear fear, and uses of radiation in (bio)medicine, STS and science communication. Field visits to research reactors and cancer centers were arranged to showcase the diverse applications of nuclear radiation. Experts involved in various related spheres of influence shared their perspectives on matters such as technological developments in emergency preparedness, nuclear reactors, and societal impacts. RESULTS: The interactive facilitator-student sessions helped educate young minds about nuclear radiation. A post-course survey was conducted to obtain opinions of students on their perceptions of reliability and safety of nuclear energy, effectiveness of the seminar, and where radiation ranked relative to alternative energy sources. Overall findings of the survey indicated that although nuclear energy was perceived as a safe and reliable substitute, renewable energy was considered a better option. Participants felt that, as per the learning objectives, the sessions were effective in improving awareness regarding nuclear energy. CONCLUSION: This seminar-style module equipped students with the analytical tools required to critically assess sources of knowledge and social perceptions of radiation. In addition to the concluding perceptions toward nuclear energy from the post-course survey, a pre-module/course survey to reveal changes in student attitudes is planned to aid refinement of the course in future iterations. Such educational efforts will allow students to be aware of both the pros and cons of nuclear radiation and thus, construct informed opinions.

[Effect of nuclear radiation on rat model of decompression sickness induced by large depth rapid floating escape].

Objective: To investigate the effects of different doses of nuclei exposure at different time on morbidity, mortality, and damage indicators in a rat model of decompression sickness caused by rapid flotation escape at a large depth. Methods: Eighty male SD rats were randomly divided into blank control group, escape control group and six intervention groups (escape at 4 hours after 4 Gy radiation, escape at 4 hours after 6 Gy radiation, escape at 4 hours after 12 Gy radiation, escape at 8 hours after 4 Gy radiation, escape at 8 hours after 6 Gy radiation, escape at 8 hours after 12 Gy radiation). Rats in intervention groups were exposed to different doses of γ-ray (4,6,12 Gy, respectively), and then were carried out a large depth and rapid buoyancy escape experiment (maximum pressure depth of 150 m). The changes of lung W/D, spleen index and plasma IL-1ß levels were analyzed. Results: Compared with the blank control group, decompression sickness incidence and mortality of rats in escape groups after nuclear exposure were increased significantly. In 4 Gy and 6 Gy irradiation groups, higher morbidity and mortality were observed in rats which escaped at 4 h post nuclear exposure when compared with rats in 8 h groups. Consistent with the changes in morbidity and mortality, the wet / dry ratio of lung tissue, the pathological damage of lung tissue, and the decrease of spleen index showed the same trends: the changes were obvious at 4 h after lower doses nuclear radiation (4 Gy and 6 Gy), not at 8 h. However, these indicators all changed markedly at 4 and 8 h after higher doses nuclear radiation (12 Gy). Plasma IL-1ß levels were significantly increased in each post-radiation exposure group when compared with the blank control group and the exposed control group. Conclusion: Nuclear radiation-induced lung injury, the damaged immune function and elevated plasma inflammatory factor concentrations increase the risk of decompression sickness after rapid ascent.

Detection of radioactivity of unknown origin: Protective actions based on inverse modelling.

The detection of radioactivity of unknown origin necessitates the use of models that can quantify unknown corresponding source term parameters. In this work, a method for solving this inverse problem is described. The main goal of the method is that it can be used in emergency response. Therefore, the full modelling chain dealing with the collection and pre-processing of measurement data, source term estimation, (forward) dispersion modelling, and consequence assessment are discussed. Firstly, to verify this inverse model SHERLOC, the part of the modelling chain concerning the source term estimation based on measurement data, is applied to the first episode of the European Tracer Experiment (ETEX). Secondly, the complete model chain is applied to a release that is still unaccounted for; the 106Ru measured in the atmosphere of Europe in September and October of 2017. It is estimated that during the night of the 25th to the 26th of September 2017 approximately 1.33 PBq (1.33×1015 Bq) of 106Ru was emitted at a location in the region of the Southern Urals in the Russian Federation. Statistical indicators show that the modelled levels of concentration are in good agreement with the measurements. The radiological consequences of the release are estimated to be minor at distances farther than 22 km from the estimated source. However, in the vicinity of the emission the maximum committed dose received by the public may have exceeded 100 mSv. Since the presented approach can be executed within few hours after the collection of measurement data it can be used in the emergency response following the detection of radioactivity of unknown origin.

Lightweight Image Restoration Network for Strong Noise Removal in Nuclear Radiation Scenes.

In order to remove the strong noise with complex shapes and high density in nuclear radiation scenes, a lightweight network composed of a Noise Learning Unit (NLU) and Texture Learning Unit (TLU) was designed. The NLU is bilinearly composed of a Multi-scale Kernel Module (MKM) and a Residual Module (RM), which learn non-local information and high-level features, respectively. Both the MKM and RM have receptive field blocks and attention blocks to enlarge receptive fields and enhance features. The TLU is at the bottom of the NLU and learns textures through an independent loss. The entire network adopts a Mish activation function and asymmetric convolutions to improve the overall performance. Compared with 12 denoising methods on our nuclear radiation dataset, the proposed method has the fewest model parameters, the highest quantitative metrics, and the best perceptual satisfaction, indicating its high denoising efficiency and rich texture retention.

New approach to removal of hazardous Bypass Cement Dust (BCD) from the environment: 20Na2O-20BaCl2-(60-x)B2O3-(x)BCD glass system and Optical, mechanical, structural and nuclear radiation shielding competences.

In the present work, aiming to collaborate in the removal of Bypass Cement Dust (BCD) from the environment, we studied a system consisting of three glasses prepared from analytical reagent grade chemicals with the following composition: 20Na2O-20BaCl2-(60-x)B2O3-xBCD, where (x = 0, 10, and 20 %). BCD is an important contributor of many respiratory human health issues. In this work we investigate their optical, physical and gamma-ray shielding properties. The experimental results of mass attenuation coefficients are contrasted with the FLUKA Monte Carlo code and the XCOM database at 0.081, 0.356, 0.662, 1.173, and 1.332 MeV photon energies. Additionally, the mechanical, structural, and optical properties of these glasses were measured. A rising peak with an increase of BCD concentration in the region from 450 cm-1 to 480 cm-1 was observed. The results show that shielding properties such as the mass attenuation coefficient (µm), the effective atomic number (Zeff), and the effective electron density (Nel) increase as BCD fraction increases. The half value layer (HVL), the tenth value layer (TVL), and the mean free path (MFP) decrease as the BCD content increases. It is noticed that 20Na2O-20BaCl2-(60-x)B2O3-xBCD, where (x = 0, 10, and 20 %), has the highest optical conductivity value at x = 20%. It was found that the gradual addition of BCD content increases the hardness of the studied glasses.

Application of nanoformulations and nanomaterials in the decorporation of radionuclides / 中华放射医学与防护杂志

Internal contamination of radionuclides in the event of nuclear emergencies can lead to serious harm to human health. The research and development of radionuclide chelating agents and the application of new technologies can reduce the internal damage caused by radionuclides. Compared with traditional preparations, the nano-preparations have the advantages of improving drug dissolution, targeting and positioning drug release, and easily passing through biofilm barrier. In recent years, many scholars have used different nano-preparation forms for different decorporation drugs, including nanoparticles, nano-liposomes, nano-emulsions, etc., to conduct related research in order to achieve better clinical application effects. Nanomaterials with excellent properties have the advantages of high efficiency, rapid adsorption and high biocompatibility, etc., and have been used more and more widely in radionuclide decorporation. In this paper, combined with the relevant literatures at home and abroad, the internal contamination of radionuclides is classified according to nuclide-deposited sites of tissues and organs, and the applications of related nanoformulations and nanomaterials in radionuclide decorporation are introduced in order to provide reference for further research.

Discussion on establishment and management of national health emergency team for nuclear radiation emergency / 中国辐射卫生

Objective To study the personnel composition, task, equipment and management of the national health emergency teams for radiological or nuclear emergency. Methods According to the responsibility and task division of the health emergency team for nuclear radiation emergencies, the national medical rescue team for nuclear radiation health emergency was established and equipped, and the management work such as training and exercise was carried out based on the potential scenario during a nuclear or radiological emergency. Results The national health emergency team for radiological or nuclear emergency was composed of professionals in the fields of radiation protection and monitoring, medical treatment, internal and external contamination treatment, food and drinking water testing, management personnel and logistics support personnel. Training and exercises is an important means to determine whether the technical capability and the equipment of the team are reasonable. Conclusion Standardized equipment and management of the emergency teamscouldensure the rapid response and efficient implementation of nuclear radiation health emergency work in all kinds of natural disasters and public health emergencies.

The Use of Public Health Indicators to Assess Individual Happiness in Post-Disaster Recovery.

PURPOSE: Very few studies have examined the influential factors of survivors' feelings of happiness in the context of nuclear accidents. This paper aims to fill this gap with reference to the recovery process in Fukushima City following the 2011 Tohoku Earthquake Tsunami in Japan. METHODS: Open access data were sourced from the 2015 Social Survey on Living and Disaster Recovery (SSLDR) (N = 1439) of Fukushima citizens. Pearson's Chi-square Test and the t-test were employed to examine gender differences with regard to happiness and exploratory variables. Following this, a multiple linear regression analysis was conducted to investigate the determinants of happiness. RESULTS: The results showed that, compared to females, male respondents were unhappier and reported more property loss and less neighborhood connectedness. Individuals' mental and physical health and neighborhood connectedness were found to be significantly correlated with their happiness. However, the disaster-related variables of people's evaluation of recovery achievement, concerns around the health impacts of radiation, property loss in the disaster, and experiences of casualty, had no effects on happiness. CONCLUSION: These findings indicate that policies and countermeasures dealing with disaster recovery over the long term should continuously focus on health issues and social relationships.

Ammonium Fluoride Passivation of CdZnTeSe Sensors for Applications in Nuclear Detection and Medical Imaging.

Cadmium zinc telluride selenide (Cd1-xZnxTe1-ySey or CZTS) is one of the emerging CdTe-based semiconductor materials for detecting X- and gamma-ray radiation at or near room temperature (i.e., without cryogenic cooling). Potential applications of CZTS sensors include medical imaging, X-ray detection, and gamma-ray spectroscopy. Chemical passivation of CZTS is needed to reduce the conductivity of Te-rich surfaces, which reduces the noise and improves the device performance. In this study, we focus on the effect of surface passivation of CZTS using a 10% aqueous solution of ammonium fluoride. The effects of the chemical treatment were studied on the leakage current, charge transport measured as the electron mobility-lifetime (µτ) product, and the spectral resolution measured as the full-width at half-maximum (FWHM) of specific peaks. After passivation, the leakage current increased and began to decrease towards pre-passivation levels. The energy resolutions were recorded for eight applied voltages between -35 V and -200 V. The results showed an average of 25% improvement in the detector's energy resolution for the 59.6 keV gamma peak of Am-241. The electron µτ product was unchanged at 2 × 10-3 cm2/V. These results show that ammonium fluoride is effective for chemical passivation of CZTS detectors.

Nuclear radiation and prevalence of structural birth defects among infants born to women from the Marshall Islands.

BACKGROUND: With their unique history of exposure to extensive nuclear testing between 1946 and 1958, descendants of Marshall Island residents may have underappreciated genetic abnormalities, increasing their risk of birth defects. METHODS: We conducted a retrospective cohort study of resident women with at least one singleton live birth between 1997 and 2013 in northwest Arkansas using state birth certificate data linked to data from the Arkansas Reproductive Health Monitoring System, a statewide birth defects registry. We calculated unadjusted and adjusted prevalence ratios (PR) and 95% confidence intervals (CI) from modified Poisson regression analyses for non-Hispanic (NH) whites, NH-blacks, Hispanics and Marshallese, using NH-whites as the reference group. RESULTS: Of the 91,662 singleton births during the study period, 2,488 were to Marshallese women. Due to the relatively small number of Marshallese births, we could not calculate prevalence estimates for some defects. Marshallese infants had higher rates of congenital cataracts (PR = 9.3; 95% CI: 3.1, 27.9). Although the number of defects was low, Marshallese infants also had higher rates of truncus arteriosus (PR = 44.0; 95% CI: 2.2, 896.1). CONCLUSIONS: Marshallese infants may have increased risk of specific birth defects, but estimates are unstable because of small sample size so results are inconclusive. Larger population-based studies would allow for further investigation of this potential risk among Marshallese infants.

Advances in Nuclear Radiation Sensing: Enabling 3-D Gamma-Ray Vision.

The enormous advances in sensing and data processing technologies in combination with recent developments in nuclear radiation detection and imaging enable unprecedented and "smarter" ways to detect, map, and visualize nuclear radiation. The recently developed concept of three-dimensional (3-D) Scene-data fusion allows us now to "see" nuclear radiation in three dimensions, in real time, and specific to radionuclides. It is based on a multi-sensor instrument that is able to map a local scene and to fuse the scene data with nuclear radiation data in 3-D while the instrument is freely moving through the scene. This new concept is agnostic of the deployment platform and the specific radiation detection or imaging modality. We have demonstrated this 3-D Scene-data fusion concept in a range of configurations in locations, such as the Fukushima Prefecture in Japan or Chernobyl in Ukraine on unmanned and manned aerial and ground-based platforms. It provides new means in the detection, mapping, and visualization of radiological and nuclear materials relevant for the safe and secure operation of nuclear and radiological facilities or in the response to accidental or intentional releases of radioactive materials where a timely, accurate, and effective assessment is critical. In addition, the ability to visualize nuclear radiation in 3-D and in real time provides new means in the communication with public and facilitates to overcome one of the major public concerns of not being able to "see" nuclear radiation.

Long-term neutron radiation levels in distressed concrete biological shielding walls.

Neutron radiation can deteriorate mechanical properties of the concrete materials, and thus it is questionable that neutron transport properties of concrete can remain unchanged during the life span of biological shielding walls. one-speed neutron diffusion equation and heat conduction equation were used as governing equations for prediction of neutron radiation and thermal field in concrete, respectively. The potential variations of transport properties due to neutron radiation and elevated temperature were estimated. A simplified example of a typical concrete biological shielding wall was analyzed up to 80 years, and the results were discussed. The radiation damage and radiation heating lead to minor changes of the temperature profile in the concrete. However, neutron radiation and elevated temperature can result in considerable increases of neutron flux and fluence in the concrete. The damage of concrete induced by neutron radiation and elevated temperature can considerably accelerate the penetration of neutron radiation into the concrete. This work is the first attempt to deal with the degradation of neutron and heat transport properties of concrete and its effect on neutron fluence distribution in concrete, and provides a possible way to determine the long-term neutron and thermal fields in concrete biological shielding walls.

Detection of Nuclear Sources by UAV Teleoperation Using a Visuo-Haptic Augmented Reality Interface.

A visuo-haptic augmented reality (VHAR) interface is presented enabling an operator to teleoperate an unmanned aerial vehicle (UAV) equipped with a custom CdZnTe-based spectroscopic gamma-ray detector in outdoor environments. The task is to localize nuclear radiation sources, whose location is unknown to the user, without the close exposure of the operator. The developed detector also enables identification of the localized nuclear sources. The aim of the VHAR interface is to increase the situation awareness of the operator. The user teleoperates the UAV using a 3DOF haptic device that provides an attractive force feedback around the location of the most intense detected radiation source. Moreover, a fixed camera on the ground observes the environment where the UAV is flying. A 3D augmented reality scene is displayed on a computer screen accessible to the operator. Multiple types of graphical overlays are shown, including sensor data acquired by the nuclear radiation detector, a virtual cursor that tracks the UAV and geographical information, such as buildings. Experiments performed in a real environment are reported using an intense nuclear source.

Design of personal dosimeter system based on ZigBee wireless network / 医疗卫生装备

Objective To research and design-an personal dosimeter system to provide data for nuclear radiation injury protection.Methods The overall architecture,hardware module and software of the system were designed with ZigBee wireless network technology and the principle.The system was composed of a terminal node,a router and a coordinator.Results The system could collect the information on nuclear radiation dosage of the serviceman within 1 km,and then the data were uploaded with the wireless network.Conclusion The system gains advantages in low power consumption,low cost,low interference and etc,and plays a very important role for commander to hold the combatants' nuclear radiation dose in the battlefield.In addition the system can also be applied in civilian field to enhance the personal dose management.