Sources Of Ionizing Radiation Research Articles

Experimental study of dosimetric properties of thermoluminescent powder TLD-100

The creation of a scientifically substantiated quality assurance system for dosimetry and the optimization of medical exposure of the population of Ukraine during diagnostic and therapeutic procedures (and the possibility of dosimetric control and monitoring of emergency situations) falls within the field of the application of ionizing radiation sources (IRs). Trends in modern medicine in most countries, including Ukraine, prove a continued increase in the share of medical exposure. The main requirements and recommendations for the use of IRs for medical purposes while ensuring the radiation safety requirements for patients are provided in the documents of such International Organizations as the International Commission on Radiological Protection (ICRP), the International Atomic Energy Agency (IAEA), the World Health Organization (WHO) and the European Commission (EC).
 One of the key factors to ensure the quality of radiation therapy is metrological and dosimetric support. To enhance the effectiveness of radiation treatment and reduce the number of complications in the future, it is necessary to irradiate the local target within the patient’s body with a dose error of no more than 5%. Control of the radiation output of the therapeutic device, i.e., the calibration of the therapeutic beam used in the treatment process, is an essential element of radiation therapy.
 Radiation protection programmes are based on checking the accuracy of the calibration of remote radiotherapy devices using thermoluminescent dosimeters (TLDs) – small plastic capsules filled with thermoluminescent powder that are sent by post to radiology centres for exposure to a specific dose in a water phantom.
 Radiation therapy in Ukraine is primarily conducted using cobalt machines, X-ray therapy devices and linear accelerators.
 The results of the study include the examination of the dependency of measurement results on various exposure parameters using the automatic reader PCL-3, the determination of dosimetric characteristics of the thermoluminescent powder TLD-100, and the development of a calibration method for thermoluminescent dosimeters under standard irradiation conditions on a remote gamma therapy device.
 Therefore, the accuracy of beam calibration using TLD dosimeters has been studied, which will enable to timely detect errors in clinical dosimetry and reduce the number of cases of radiation-related complications for patients during their treatment.

Development of Gamma Flaw Detectors for Non-Destructive Testing

The radiographic method of control is implemented by a set of control tools in the form of gamma flaw detectors, which are distinguished by: mobility, reliability, radiation safety, adaptability to a wide climatic range, ease of operation, and the ability to control products with small and large radiation thicknesses. The paper describes portable gamma flaw detectors manufactured by JSC NIITFA: Gammarid 2010R, UNIGAM R, Stapel-5 Se75 Ir192, Stapel-5 Se75W, gamma flaw detector γ-RID-75/80R and stationary gamma flaw detectors RID K-100 and RID K-400. Also paper describes a brief technology for the production of ionizing radiation sources Ir-192 with activity of 120 Curie, a technology for rolling the source holder with Ir-192 source and completing the Ir-192 source with a portable gamma flaw detector Gammarid-192/120M in the INP AS.

Assessment of the clinical and hematological status in acute radiation damage of Leningrad calico chickens

The problem of radiation damage to the human body, animals, birds and its individual systems and organs against the background of the use of ionizing radiation sources has acquired relevance throughout the world over the past decades. In the event of an emergency, acute radiation damage in poultry will be massive and increase the risks of developing infectious and noninfectious diseases, due to a decrease in the level of specific resistance, low effectiveness of therapeutic and preventive measures and, as a result, will lead to a decrease in the quality of the resulting product. In view of this, studies aimed at studying the features of the course of radiation pathology in chickens are very relevant and will be taken into account when developing and applying radioprotective formulations.The study of the features of the course of acute radiation damage caused by uniform single irradiation at doses of 7 Gy; 9 Gy; 11 Gy and 13 Gy, at a power of 0.99 Gy/min, was carried out on Leningrad calico chickens. Resistance to ionizing radiation was assessed by generally accepted clinical and hematological methods. Pronounced changes in clinical manifestations and shifts in morphological parameters of peripheral blood were noted under the influence of gamma radiation. Thus, irradiation of chickens with doses of 11 Gy and 13 Gy caused the development of acute radiation damage of an extremely severe degree, which led to severe depression, refusal of feed, shortening the duration or absence of a latent period, against the background of severe leuko- and erythropenia. Irradiation with a dose of 9 Gy caused severe acute radiation damage characterized by adynamia, reduced feed intake, diarrhea with an admixture of blood. Leukopenia was noted in the blood, which by day 12 values were lower than before irradiation by 41.9% and erythropenia. During acute radiation damage in chickens, when irradiated at a dose of 7 Gy, the development of the initial, latent, peak and recovery period in the surviving individuals was clearly traced. The clinical manifestation was characterized by a complex of dyspeptic and neuromotor disorders, moderate leukopenia was noted in the blood. In all experimental chickens, a violation of egg production was noted, up to complete cessation against the background of irradiation at doses of 11 Gy and 13 Gy. It is concluded that uniform single irradiation of chickens in doses from 7 Gy to 13 Gy leads to acute radiation damage and negatively affects the productive qualities of poultry. In order to conduct the experiment on the principle of pairs of analogues, 5 groups of animals were formed, 10 chickens in each. Determination of the content of erythrocytes, leukocytes and platelets in the blood was determined by counting in the Goryaev chamber. External total single exposure to gamma radiation at doses of 7 Gy, 9 Gy, 11 Gy and 13 Gy led to the development of acute radiation exposure of medium, severe and extremely severe degrees, respectively.

GUI development for SSDL to calibrate photon measuring equipment

Current legislation mandates the inspection and calibration of operational survey radiation monitoring instruments used in nuclear medicine, radiotherapy departments, and other fields utilizing ionizing radiation sources. To comply with national and international radiation protection standards, Morocco's National Secondary Standard Dosimetry Laboratory provides reliable calibration results with high accuracy and covers various measurement ranges using attenuators provided by the automated Gamma G10 irradiator or validated beam qualities produced by the X-ray irradiator type X80–320 kV.This study aims to develop a digital graphical user interface using Python programming language, designed for calibrating radiation protection measuring instruments . The interface is intended to facilitate all operations and calculations related to determining calibration factors and measurement uncertainties in accordance with the ISO 4037 standard, ensuring minimal processing time and minimizing potential error sources . The interface enables calculations to be recorded, as well as the establishment and electronic archiving of the calibration certificate and the report in PDF format using the Hypertext Preprocessor FPDF library (PHP FPDF). With the development of this interface, multiple instruments can be processed per day with high accuracy, streamlining the calibration process and improving efficiency.•The importance of compliance with international standards to ensure the quality and reliability of measurements in radiation protection was examined.•Description of X-ray and Gamma-ray irradiators designed for the calibration of radiation protection measuring instruments within the Secondary Dosimetry Calibration Laboratory (SSDL) which is a member of the WHO/IAEA network within the National Center for Radiation Protection of Morocco•Graphical User Interface using python for the calibration of photon measurement instruments for radiation protection purposes was developped.

Риск заболеваний щитовидной железы, связанных с йодной недостаточностью, ликвидаторов последствий аварии на Чернобыльской АЭС ‒ работников предприятий атомной промышленности

Purpose: Assessment of thyroid disease risk associated with iodine deficiency, liquidators of the Chernobyl accident consequences, employees of nuclear industry enterprises depending on the doses of different types of exposure. Material and methods: The dose-risk assessment study included 12663 men, 1327 of whom had occupational exposure data. A Poisson’s process with intensity parameter was chosen as a statistical model of morbidity risk. The statistical package of epidemiological data analysis EPICURE was used for the estimation of excess relative risk (ERR) of thyroid diseases related to iodine deficiency. There was conducted a cohort epidemiological study of a group of liquidators who worked in the 30-km zone in 1986‒1990 over a period of more than thirty years depending on the dose received both during liquidation of the Chernobyl accident consequences and during professional work with radioactive substances (RS) and ionizing radiation sources (IRS). Results: As a result of the study direct estimates of radiogenic risk of thyroid diseases associated with iodine deficiency in the liquidators of the Chernobyl accident consequences were obtained for the first time using the data on doses of Chernobyl and the sum of these doses with the doses of occupational exposure. It is shown that the risk of disease per unit dose (ERR/Zv) for dose loads received both at liquidation of Chernobyl accident consequences and for total doses give different results. Conclusion: Assessment of the risk of thyroid diseases associated with iodine deficiency, liquidators of the Chernobyl NPP accident consequences and workers of nuclear industry enterprises, serviced by FMBA health care institutions of Russia using the doses of different types of exposure gives different results. Correct results of assessing the risk of radiation-related diseases can only be given by the register using the total radiation dose (occupational, accidental, medical, natural), as required by the directive documents.

РАДИАЦИОННЫЕ ИСТОЧНИКИ И ДОЗЫ ОБЛУЧЕНИЯ ПЕРСОНАЛА И ПАЦИЕНТОВ ПЭТ-ЦЕНТРА

Introduction 1. Emissions in cyclotron facility and their influence on staff 2. Radiation sources of radiochemical laboratory and radiation exposure of radiochemists 3. Ionizing radiation sources in PET diagnostics division and doses of medical staff 4. Doses of PET center patients Conclusion

ПРОГНОЗ РАДИАЦИОННЫХ РИСКОВ РАКА ЩИТОВИДНОЙ ЖЕЛЕЗЫ СРЕДИ НАСЕЛЕНИЯ РАЙОНОВ БРЯНСКОЙ ОБЛАСТИ, ЗАГРЯЗНЕННЫХ ВСЛЕДСТВИЕ АВАРИИ НА ЧЕРНОБЫЛЬСКОЙ АЭС, С УЧЕТОМ НЕОПРЕДЕЛЕННОСТЕЙ ОЦЕНОК МОДЕЛЕЙ РИСКА

Purpose: Forecasting the lifetime attributable radiation risk of incidence with malignant neoplasm (MN) of the thyroid gland and identifying groups of increased radiation risk (HR) for the population of the Bryansk region currently (at the beginning of 2023) living in six areas most contaminated with radionuclides after the accident at Chernobyl NPP, based on a conservative approach, taking into account dose uncertainty factors and parameters of mathematical risk models. Material and methods: The mathematical model of the radiation risk of thyroid cancer is the model recommended by the International Commission on Radiological Protection (ICRP). The uncertainty assessment of radiation risks was carried out by simulation modeling, i.e. by multiple calculation of random realizations of the risk using the normal or log-normal distribution of all parameters involved in the calculation of this risk. Based on a set of random realizations, 95 % confidence limits of risks were estimated. The Unified Federal Database of the National Radiation and Epidemiological Register (NRER) containing reconstructed absorbed doses in the thyroid gland in the population was used as the initial data for the calculation. Results: At the beginning of 2023, the group of 37–40-year-old women is characterized by the maximum radiation risks of thyroid cancer. According to conservative estimates (according to the upper 95 % confidence limits of radiation risk assessments), up to 19.9 % of people from this group may experience the development of radiation-induced thyroid cancer in the future, and for 37-year-old women this proportion can be up to 30.0 %. The greatest risk is predicted for people living in the Krasnogorsk district of the Bryansk region. Radiation-induced thyroid cancer can develop in 40.1 % of individuals from this group. Radiation risks of thyroid cancer in men are up to 10 times lower than in women. For 74.5 % of the population of the entire studied cohort, it is predicted that the maximum individual risk of 5.0×10-5, established by NRB-99/2009 for the population under normal operation of ionizing radiation sources, will be exceeded. Conclusions: At present (since 2023 and for life), the population of the most polluted districts of the Bryansk region continues to be at a high risk of developing radiation-induced thyroid cancers. Women at the age of 0–3 years at the time of exposure (in 1986) should be allocated to the maximum risk group. The results of this work can be used in the preparation of recommendations by health authorities to improve medical monitoring of exposed citizens.

Effects of ionizing radiation sources and dose levels on quality characteristics of meal ready to eat (Minced cow meat)

Effects of ionizing radiation sources and dose levels on quality characteristics of meal ready to eat (Minced cow meat)

Effects of ionizing radiation sources and dose levels on quality characteristics of meal ready to eat (Minced cow meat)

Effects of ionizing radiation sources and dose levels on quality characteristics of meal ready to eat (Minced cow meat)

КАНЦЕРОГЕННІ РИЗИКИ ДЛЯ НАСЕЛЕННЯ МИКОЛАЇВСЬКОЇ ОБЛАСТІ ВІД ТЕХНОГЕННО-ПІДСИЛЕНИХ ПРИРОДНИХ ДЖЕРЕЛ ІОНІЗУЮЧОГО ВИПРОМІНЮВАННЯ

The article highlights the materials of our own research on the assessment of carcinogenic risk from technogenically enhanced natural sources of ionising radiation. The study was carried out for the Mykolaiv region, whose geological features in the north contribute to an increased burden on the population from natural sources of ionising radiation. The study used materials from well-known radioecological and dosimetric studies in the Mykolaiv region. The presence of a carcinogenic risk from ionising radiation sources encountered in everyday life was confirmed. The cancer incidence and mortality rates among the population from different regions of the Mykolaiv region, which differ in the magnitude of the dose load on the population from natural and artificial radiation, were determined and analysed. There is a difference in the average annual growth rates of cancer incidence and mortality for regions with different levels of human exposure to man-made and artificially enhanced sources of ionising radiation of natural origin.

Cosmic-Ray Tomography for Border Security

A key task for customs workers is the interception of hazardous, illegal and counterfeit items in order to protect the health and safety of citizens. However, it is estimated that only a small fraction of cargo is inspected and an even smaller fraction of trafficked goods are detected. Today, the most widely used technology for scanning vehicles, ranging from vans and trucks to railcars, is γ ray and X-ray radiography. New technologies are required to overcome current technological shortcomings, such as the inability to detect the target material composition, the usage of harmful ionising radiation sources and the resultant low throughput. Cosmic ray tomography (CRT) is a promising technology for cargo screening. Cosmic ray muons have average energies of around 10,000 times larger than a typical X-ray and therefore can penetrate relatively large and dense materials. By analysing muon scattering, it is possible to identify materials hidden inside shielding that is too thick or deep for other imaging methods. CRT is also completely passive, exploiting naturally occurring secondary cosmic radiation, and is therefore safe for humans and animals. Contrary to conventional X-ray- or γ-ray-based imaging techniques, CRT also allows material differentiation and anomaly localisation within the cargo or vehicle through the provision of 3D images. This article reviews the current state-of-the-art technology in CRT, critically assessing the strengths and weaknesses of the method, and suggesting further directions for development.

The Effects of Different Gamma-Ray Doses on Safflower (Carthamus Tinctorius L.) Varieties on Agricultural Features Observed in M1 and M2 Plants

The research was carried out with the ionizing radiation source Cobalt 60 (Co-60) at a dosage of 200, 300, 400, 500 Gy on three safflower varieties. According to the results of the research, in M1 plants; in parallel with the increase in gamma dosages, a certain decrease occurred in plant height, number of branches per plant, number of trays per plant, diameter of the tray, number of seeds per tray, seed yield per plant, and seed vitality. In field observations taken from M2 plants, significant diversity was observed. In M2 plants, significant reductions in emergence rate were observed in all three cultivars depending on the increase in dosages. In all three safflower cultivars, plant height, tray diameter, number of seeds per tray and thousand seed weight values increased compared to control plants in parallel with the increase in dosages. Significant mutations were observed in the 200-400 Gy dosage range in all three cultivars. In M1 plants, when the seed yield per plant and the rate of viability were examined, a certain level of decrease was observed in parallel with the increase in gamma dosages. In M2 plants, in parallel with the dosage increase in all cultivars, the tray diameter values increased compared to the control. Again, in all cultivars, while the diameter of the tray decreased in M1, it increased in M2 in general and increases were observed at low gamma dosages. In M2, dosages of 300-400 Gy also increased in the criteria examined compared to the control and had a stimulating effect. The investigated properties generally decreased in M1 depending on the dosage increase, while there were fluctuations in M2. As a result, the variation created by the radiation and the real effect of the mutation applications emerged after M2. In this study, while the averages of Dinçer and Remzibey cultivars in terms of viability in M1 were almost the same, Shifa cultivar gave more successful results in terms of viability. When the values obtained in the study were examined, it was concluded that genetic variations and changes occurred at dosages of 300-400 Gy at most.

Analysis of the radiation levels in the population of the Oryol region during X-ray radiological studies

The article deals with the problems of medical exposure (ME), since it is the predominant source of artificial exposure and one of the essential types of exposure of the population as a whole. In the course of the study, the dose load of ionizing radiation sources (IRS) used for medical purposes on the population of the Oryol region in 1998–2018 was analyzed based on the results of the analysis of the fleet of X-ray diagnostic equipment, data from radiation passports and official annual medical statistics. To achieve the goal of the study, statistical methods were used, methods of retrospective epidemiological analysis of data on medical exposure of the population of the Oryol region. We used data from 15 million X-ray procedures recorded by the official annual medical statistics of dynamic changes over 20 years from 1998 to 2018 (form No. 30) and data from 800 annual No. 3‑DOZ — forms of federal state statistical observation in the Oryol region for the period 2001–2018 provided by medical institutions. The patient pays for information with a high risk of radiation exposure. The reason for the increase in medical exposure is the increasing use of interventional radiology in recent years. Medical exposure carries the risk of stochastic effects. The incidence of malignant neoplasms among the population of the Oryol region has increased by 14 % over the past 5 years, adolescents — 1.3 times, children under 14–1.4 times; congenital anomalies and malformations were recorded — 1.3 times more, in children under 14 years of age there was an excess of 4.5 %. The health indicators of the population of the Oryol region are considered unsatisfactory in terms of the incidence of malignant neoplasms, mortality and congenital malformations. As a result of the research, proposals were made to optimize the dose load and reduce the radiation hazard to the health of the population of the Oryol Region. Recommendations have also been developed to reduce the radiation doses to the personnel of medical and prophylactic organizations, to re-equip the health care facilities with modern low-dose devices.

Global Transcriptional Response of Escherichia coli Exposed In Situ to Different Low-Dose Ionizing Radiation Sources.

Characterization of biological and chemical responses to ionizing radiation by various organisms is essential for potential applications in bioremediation, alternative modes of detecting nuclear material, and national security. Escherichia coli DH10β is an optimal system to study the microbial response to low-dose ionizing radiation at the transcriptional level because it is a well-characterized model bacterium and its responses to other environmental stressors, including those to higher radiation doses, have been elucidated in prior studies. In this study, RNA sequencing with downstream transcriptomic analysis (RNA-seq) was employed to characterize the global transcriptional response of stationary-phase E. coli subjected to 239Pu, 3H (tritium), and 55Fe, at an approximate absorbed dose rate of 10 mGy day-1 for 1 day and 15 days. Differential expression analysis identified significant changes in gene expression of E. coli for both short- and long-term exposures. Radionuclide source exposure induced differential expression in E. coli of genes involved in biosynthesis pathways of nuclear envelope components, amino acids, and siderophores, transport systems such as ABC transporters and type II secretion proteins, and initiation of stress response and regulatory systems of temperature stress, the RpoS regulon, and oxidative stress. These findings provide a basic understanding of the relationship between low-dose exposure and biological effect of a model bacterium that is critical for applications in alternative nuclear material detection and bioremediation. IMPORTANCE Escherichia coli strain DH10β, a well-characterized model bacterium, was subjected to short-term (1-day) and long-term (15-day) exposures to three different in situ radiation sources comprised of radionuclides relevant to nuclear activities to induce a measurable and identifiable genetic response. We found E. coli had both common and unique responses to the three exposures studied, suggesting both dose rate- and radionuclide-specific effects. This study is the first to provide insights into the transcriptional response of a microorganism in short- and long-term exposure to continuous low-dose ionizing radiation with multiple in situ radionuclide sources and the first to examine microbial transcriptional response in stationary phase. Moreover, this work provides a basis for the development of biosensors and informing more robust dose-response relationships to support ecological risk assessment.

Consequences of parental preconceptional irradiation: Endocrine-metabolic pathology in offspring

Epidemiological studies of late effects of preconceptional (prior to conception) radiation exposure are necessary in order to understand the risks of tumor and non-tumor pathology in next generations. Research of possible relation between parental preconceptional exposure and development of endocrine and metabolic disorders in the offspring is one of the topical issues of radiation hygiene. The objective of the study: comparative analysis of endocrine and metabolic pathology in children of the individuals exposed to long term preconceptional external gamma-radiation at the Mayak Production Association – at the first atomic industry facility on Russia. Materials and methods: A retrospective research was performed based on the Ozyorsk Children’s Health Registry. Ozyorsk – the city where Mayak Production Association is the enterprise forming the city. Analysis of endocrine and metabolic disorders was performed for 13880 children of 1949-1973 years of birth who were born and resided in Ozyorsk; parents of 9321 children of this number had accumulated doses of prolonged external gamma-radiation exposure at the production facility prior to conception. A comparative analysis of the structure and incidence of “Endocrine, nutritional and metabolic diseases” and nosological forms of this class of pathology was performed. Characteristic features of parental preconceptional exposure were analyzed in relation to thyroid pathology in children. Relative risk of endocrine and metabolic disorders among the children of exposed and unexposed parents was calculated for the whole disease class and for certain nosologies. Results: A significant predominance of thyroid diseases, particularly, iodine deficiencies, was detected at an earlier age among the offspring of Mayak Production Association workers compared to the control group; these cases were mostly related to low dose parental preconceptional exposure. Thyroid cancer was further detected in 0.16% (15/9321) of the studied cohort of the offspring of exposed parents with average manifestation age of 42.6. Relative risk of thyroid diseases was significantly higher among the exposed parents’ offspring compared to the controls: 2.0 among boys (95% confidence interval 1.38-2.9), 1.59 among girls (1.25-2.02) and in the group as a whole – 1.64 (1.34- 2.01). Relative risk of thyroid diseases related to iodine deficiency among the offspring of Mayak Production Association personnel was almost twice higher than the in the control group: 1.92 (1.3-2.84) among boys, 1.68 (1.29-2.2) among girls, 1.7 (1.36-2.12) in the whole group. Discussion and conclusion: A statistically significant overweight of non-tumor thyroid pathology in the offspring of Mayak Production Association personnel cannot be explained through external reasons taking into account similar climate and geographic conditions, possible technogenic exposure and the same unified medical survey of the followed children. We cannot exclude increased sensibility if thyroid tissue to iodine deficiency and its predisposition to hypertrophy and hyperplasia among the offspring of individuals exposed to long term occupational contact with ionizing radiation sources; that should be taken into account in the course of medical monitoring of these patients. Further research of transgenerational effects in the offspring of personnel of radiation hazardous production facilities are needed for complete understanding of the role of parental occupational exposure in health risks for further generations.

Simulating the impact of iodine as a contrast substance to enhance radiation to the tumor in a brain x-ray phototherapy

The influence of adding iodine as a contrast substance to elevate radiation in a tumor is studied using simulation techniques of Monte-Carlo. The study is carried on a brain cancer by adopting an unsophisticated head phantom. The ionizing radiation source is an external beam of x-rays with energy range of a few tens of keV. The expected radiation dose increment due to adding the iodine is investigated by comparing the radiation in the tumor after and before adding the iodine and calculating the ratio between the two doses. Several concentrations of the contrast substance are used to quantify its impact. The change of the dose increment with the source energy is also examined. It is found that the radiation elevation in the tumor tends to saturate with increasing the iodine concentration, and for the studied domain of energies (30 keV–100 keV), the radiation dose enhancement factors (RDEF) for the different iodine concentrations (1%–9%) show peaked curves, with the peak occurring between 60 keV and 70 keV. For the highest concentration studied, 9%, the peak value is almost 7.

Radiation dosimetry with a Triple-GEM detector

We studied the properties of the gaseous detector triple-GEM (triple Gas Electron Multiplier) as a dosimeter with different ionizing radiation sources used in medical applications. The detector was calibrated in energy with an Iron-55 radioactive source. We measured doses of radiation from different radioactive sources as well as from a medical portable X-ray machine, and compared them to reference values. The detector presents a linear dependence between radiation intensity and measured dose. A calibration factor of 1.13x104 was found, independently of the radiation source. These results allow us to conclude that the triple-GEM detector has the potential to be used as a dosimeter in medical applications.

An Experimental Setup Based on a Printable System for the Acquisition of the Real-Time Electrical Response of Irradiated Semiconductor Devices

Nowadays, the semiconductor market is growing exponentially in many sectors and more particularly in the applications of the Internet of Things (IoT) in “harsh” environments. These so-called harsh environments result in difficult operating conditions for electronics. To guarantee the reliability of operations in such environments, the devices must be tested in the specified extreme conditions. In the case of exposure to ionizing radiation, tests are generally carried out on specific facilities such as a cyclotron. Unfortunately, access to this kind of facilities is difficult, expensive, and time-consuming. Consequently, in an industrial environment, semiconductors are usually characterized ante- and post-irradiation up to a specific dose, which provides information about drifts in dc parameters but does not help to check any transient effect. This article proposes a portable 3-D printed test set-up allowing to realize this transient measurement while ensuring no interaction with the outside world. Moreover, the setup proposes a variation of distance to favor or not the interaction of the semiconductor with the ionizing radiation source. The main advantages of the proposed 3-D setup are its adaptability to any kind of radiation source geometry as well as its low encumbrance. These enable the possibility to use any local radiation source, other than accelerators, available in smaller facilities. Finally, a complete methodology is proposed to characterize the transient phenomena during the interaction of ionizing radiation with the semiconductor target, in order to validate the setup.

New Insights into the Understanding of Mechanisms of Radiation-Induced Heart Disease.

Cancer patients who receive high-dose thoracic radiotherapy may develop radiation-induced heart disease (RIHD). The clinical presentation of RIHD comprises coronary artery atherosclerosis, valvular disease, pericarditis, cardiomyopathy, and conduction defects. These complications have significantly reduced due to the improved radiotherapy techniques. However, such methods still could not avoid heart radiation exposure. Furthermore, people who received relatively low-dose radiation exposures have exhibited significantly elevated RIHD risks in cohort studies of atomic bomb survivors and occupational exposures. The increased potential in exposure to natural and artificial ionizing radiation sources has emphasized the necessity to understand the development of RIHD. The pathological processes of RIHD include endothelial dysfunction, inflammation, fibrosis, and hypertrophy. The underlying mechanisms may involve the changes in oxidative stress, DNA damage response, telomere erosion, mitochondrial dysfunction, epigenetic regulation, circulation factors, protein post-translational modification, and metabolites. This review will discuss the recent advances in the mechanisms of RIHD at cellular and molecular levels.

Features of 2Day.QA® as a 2D radiation dosimeter

PurposeA new commercial 2D ionising radiation dosimeter (2Day.QA®) was developed. This work aims to introduce the basic functions of 2Day.QA®. MethodsThe dosimeter is made mainly of a linear polysaccharide consisting of β(1 → 4) linked d-glucose units and radiation active substances, which make it environmentally friendly. For 2Day.QA® irradiation, radiotherapy ionising radiation sources were used. The analysis of 2Day.QA® was performed using three scanners: Vidar® Red LED Dosimetry Pro Advantage™, Vidar® VXR 12-plus™ and HP Scanjet G3010 flatbed scanner. The stability of 2Day.QA® was tested. Exemplary applications of 2DayQA® for QA studies of accelerator light and radiation field coincidence and brachytherapy source position were carried out. ResultsThe dosimeter responded to the lowest applied dose of 0.95 Gy and saturated at over 94.9 Gy. The quasi-linear dose response is below 20 Gy. Vidar® Red LED Dosimetry Pro Advantage™ has proven to be superior to other scanners at determining dose effects in 2Day.QA®. The stability of the non-irradiated 2Day.QA® is at least 18 months. After 18 months of storage, the dosimeter reacted to irradiation. In the case of the irradiated samples, a slight color drift related to the absorbed dose was observed. Tests of the use of 2Day.QA® to control the quality of the accelerator light and radiation field coincidence and brachytherapy source position have shown that it can be used for such applications. ConclusionsThe study reveals the potential of 2Day.QA® for 2D radiation dosimetry and concludes with recommendations for the use of the dosimeter for radiotherapy QA tests.