Types Of Radiation Research Articles

Prediction of Solar Ultraviolet Radiations Using Random Matrix Theory

Purpose: The correlation of different samples can be described by analytical models such as random matrix theory. In this study, we tried to describe the correlation of different types of ultraviolet values in different months, weeks, and hours to get a significant relationship of special times, which one needs to get enough intensity of the sun or avoid getting sunburn.
 Materials and Methods: To this aim, we focused on the hourly and daily mean amounts of ultraviolet A, B, and C intensities of solar radiation in Tabriz urban area were measured during a full year of 2017-2018. We used such ultraviolet values which are measured at the same hour of the day to satisfy the same symmetry criteria which are necessary in random matrix theory. These data are unfolded and classified in different sequences to analyze in the nearest neighbor spacing distribution framework via the maximum likelihood estimation technique.
 Results: Strong correlation is yielded for daily values of UVA in comparison with the other types of ultraviolet radiations. Also, we considered the dependence of correlation degrees of these three types of ultraviolet to average temperature and humidity at different months.
 Conclusion: The results propose more correlation of UVA indices in August while such correlation of UVC radiations are yielded in December.

Проращивание семян рапса при непрерывном светодиодном освещении в режимах низкоэнергетических потоков фотонов монохроматического излучения

In order to study the effect of low-energy monochrome radiation on the germination of rapeseed of the new variety Antares, the authors used light-emitting diodes of blue (440 nm), green (525 nm), red (660 nm) and far red (730 nm) light, as well as those of UV-A radiation (380 nm) with an intensity of 0.367–6.904 µmol/m2* s on different spectra. Different types of monochrome radiation affected the germination of seeds and the growth of sprouts in different ways. According to the indicators of germination energy, seed germination, weight of 100 sprouts, and yield of green mass, the best results were obtained when germinating using the green light. Based on experimental data, the patent was issued for the invention “The activation method of rapeseed germination under monospectral illumination”. Irradiation of seeds with the monochrome far-red light significantly reduced the germination ability and yield of sprouts.

An investigation on polymers for shielding of cosmic radiation for lunar exploration.

In outer space, we find many types of radiations that are due to solar flares, radiation belt, cosmic rays, etc. We are fortunate enough to be protected from these radiations on the surface of the Earth, whereas in other celestial objects such as planets and satellites, without a protecting atmosphere, penetration of radiation that may be ionising or non-ionising is inevitable. Hence, studying radiation environment and its effect on such celestial objects is very important for establishing facilities such as satellites, payloads, vehicles and human exploration. For such cases, manufacturing the products with lightweight, thermally stable, flexible, mechanically durable materials is essential and needs to be studied for the radiation effect. Hence, in the present work, we have made an attempt to calculate the rate of absorbed dose in case of polymers such as Polyvinyl Chloride (PVC), polytetrafluoroethylene, Mylar, polystyrene and Zylon for the lunar radiation environment. From the literature, it is found that ions up to iron has a lion share in the ionic radiation in space. The simulations were carried out for ions from hydrogen to iron using the SRIM software with various energies. It is observed that the absorbed dose rate in the polymers increases with the increase in ion mass. Further, the study can be extended to get the information of various flexible materials for these ions from which a suitable material can be chosen for the different space applications.

LED ДЖЕРЕЛА УЛЬТРАФІОЛЕТОВОГО ВИПРОМІНЮВАННЯ: МЕТОДИЧНЕ ТА ПРИЛАДОВЕ ЗАБЕЗПЕЧЕННЯ З УРАХУВАННЯМ ГАРМОНІЗАЦІЇ ЗАКОНОДАВСТВА ЄС ТА УКРАЇНИ

One of the effective means of disinfecting premises is its irradiation with ultraviolet bactericidal radiation (UVBV), which is in the UV-C region (200 nm - 280 nm) and for mercury lamps has a radiation peak at a wavelength of 254 nm. However, UVBV should be used competently and with appropriate caution in terms of its intensity and safety, avoiding risks of damage to human skin and eyes. Therefore, UVBV is used indoors, mainly in the absence of a person. But when using sources of this type of optical radiation in the presence of a person, proper attention should be paid to controlling the intensity of UVBV and the time of its exposure. At the same time, it should be noted that the active processes of harmonization of the legislation of the EU and Ukraine require the modernization of the regulatory and methodological base for the measurement and hygienic assessment of ultraviolet radiation in the production environment and in the environment, significantly expanding the possibilities of using UVB sources, including in the presence of humans. Therefore, the purpose of the study is to create the basis for appropriate methodological recommendations for the use of bactericidal ultraviolet monochrome LED sources for disinfection of air and surfaces in rooms, as well as the formulation of appropriate requirements for UV radiometers, which should ensure control of the technical parameters of the mentioned ultraviolet monochrome LED sources. As a result of the research, scientific principles were proposed for the instrumental and methodical control of the safe use of bactericidal ultraviolet monochrome LED sources for the improvement of air and surfaces in premises of various purposes, taking into account the requirements of the legislation of Ukraine and the EU. The technical characteristics of the available UVBV LED sources were analyzed, based on which the medical and technical requirements for UV radiometers were formulated, which should ensure control of the intensity and actinic dose of UV radiation in accordance with the requirements of DSTU EN 62471:2017 "Safety of photobiological lamps and lamp systems (EN 62471:2008 , IDT; IES 62471:2006, MOD)". Design approaches to the formation of the spectral range of RG sensitivity by using appropriate light filters, including for the blue light range (380-480 nm), have been determined. A technique for correcting the spectral characteristic of the RG sensitivity is proposed, which contributes to the reduction of the intensity measurement error created by different LED sources.

Shorter Ureters Lead to Fewer Strictures Following Cystectomy and Urinary Diversion

To identify the impact of length of distal ureteral resection on the risk of benign uretero-enteric anastomotic stricture (UEAS) formation following cystectomy and urinary diversion. A database of patients who underwent cystectomy and urinary diversion from 2015 to 2022 was analyzed. Distal ureteral resections were sent for final pathology. The length of resected ureter was collected from pathology reports. Benign UEAS were confirmed with renal scintigraphy, antegrade nephrostogram, or endoscopic evaluation. The relationship between stricture formation and clinical parameters were assessed using T-tests, Chi-square tests, and multivariable analysis. A total of 366 patients underwent cystectomy and urinary diversion. Of the cohort, 35 (9.5%) patients developed UEAS. Median time to stricture formation was 12.5 months (IQR 4-30). Of the 711 uretero-enteric anastomoses, 40 (5.6%) ultimately formed a UEAS. Median distal ureteral resection was significantly longer among ureteral anastomoses which did not form a UEAS (2.3 cm vs. 1.65 cm, p=0.028). Multivariable logistic regression adjusting for surgical approach, prior radiation, ureteral side, and urinary diversion type demonstrated that longer distal ureteral resections were inversely associated with odds of UEAS formation (OR 0.73, 95% CI 0.58-0.92). Multivariable Cox regression analysis similarly showed that length of distal ureteral resection was inversely associated with time to stricture formation (HR 0.78, 95% CI 0.62-0.98). The etiology of benign UIA strictures is multifactorial. Vascular compromise is a critical hypothesis. We found that longer distal ureteral resections (and thus shorter ureters) were associated with a significantly lower risk of stricture formation in cystectomy patients.

Matrix metal collimators studies for the spatially fractionated radiation therapy

Traditional radiation therapy is hindered by limitations in dose delivery and the risk of over-irradiation, which can harm healthy tissues surrounding tumors. Spatially fractionated and intensity-modulated radiation therapies have emerged as promising techniques to mitigate these issues by reducing damage to healthy tissues. This study explores the potential of enhancing radiation therapy's therapeutic efficacy through spatial fractionation of X-ray beams, a technique that can significantly increase radiation efficiency by reducing the dose load on healthy tissues. This research hypothesizes that microscopic lesions within the paths of micro/mini-beams can be repaired by minimally irradiated cells adjacent to the irradiated tissue slices, based on observations with high-energy (MV) photons. Spatial fractionation is particularly valuable for X-ray and electron radiation therapy, which is more widespread and cost-effective than proton therapy. The study introduces a new type of cost-effective metal matrix collimators designed for beam fractionation. These collimators are constructed using lead plates for thickness variation implementation and employ a 5x5 hole matrix with 1 mm diameter and 3 mm pitch, covering an area of 14x14 mm². To visualize beam distribution, a Timepix detector, capable of providing real-time 2D beam profiles, was employed. Experiments were conducted using a medical LINAC with typical therapeutic energy ranging from 6 to 18 MeV. Results indicate that spatial fractionation can be achieved for X-ray radiation, with a PVDR of approximately 3 for a 3 cm lead collimator. However, issues with hole uniformity and blurring in the peak area prompted a shift to using copper collimators due to their superior manufacturing properties. This study presents a novel matrix collimator design made from various materials for shaping mini beams, aimed at improving the efficiency of spatial dose fractionation for different ionizing radiation types. Geant4 simulations have been instrumental in optimizing collimator features. The findings suggest that high levels of dose fractionization can be achieved for X-rays, electrons, and proton beams. These results warrant further biological studies to evaluate the effects of fractionation on normal and tumoral tissues, supporting the practical implementation of collimation in radiation therapy.

Simulation of thin-film detectors of ionizing radiation and thermal neutrons based on CdTe

The article is dedicated to the numerical simulations of thin-layer structures based on CdTe semiconductors, which can be fabricated by using low-cost technologies. Structures Mo/Au/CdS/CdTe/Au, and their modifications, with different thicknesses of the main layers are investigated. The possibility of creating a detector of ionizing radiation based on these structures, which has selective properties with respect to the radiation type, and very low operation voltage, is shown. The detection efficiencies of α-, β-, and γ-radiation in different energy ranges were calculated based on the obtained values of energy losses of ionizing particles, which are proportional to the output signal of the detector. The use of such detectors, together with a solid-state converter made of boron carbide containing either natural boron natB or boron enriched with the 10B isotope up to 95%, for the detection of thermal neutrons was also studied. It was shown that the structures could be used to create α-particle spectrometers, given that the CdTe thickness is tailored to the highest expected α-particle energy. Detectors with thin CdTe (1–5 μm) can be successfully used in the counting mode. For neutron detection, stacking multiple single structures into sandwich structures was proposed and investigated. In such a configuration, the detector qualities were markedly improved: the efficiency of neutron detection reached ∼60%, while the sensitivity to the background γ- and β-radiation was ∼100 times lower than that for neutrons. The very low sensitivity of the simulated neutron detectors to the neutron incidence angle was shown.

Results of Treatment of Patients with Progression of Primary Highly Malignant Brain Gliomas During a Repeated Course of Radiation Therapy. Own Experience

Purpose: To determine the most effective option for repeated radiation therapy in patients with continued growth of primary high-grade brain glioma, taking into account the isodose distribution during the initial course of radiation therapy. Material and methods: As a result of a retrospective analysis, the results of treatment of 100 patients with confirmed progression of high-grade glioma treated at the Chelyabinsk Regional Center for Oncology and Nuclear Medicine in the period from 2010 to 2020 were evaluated. The ratio of men and women was approximately equal (56 men and 44 women). The mean age of patients of both sexes was 47.2±11.9 years. According to the histological conclusion, patients with glioblastomas (GB) prevailed (n = 58), 42 patients were diagnosed with anaplastic astrocytoma (AA). Reoperation was performed in 26 patients. Repeated radiation therapy in an independent variant was performed in 76 patients of them: 17 patients received a course of neuronal therapy in mono mode and in 17 patients in combination with external beam radiation therapy; 23 patients underwent stereotactic radiotherapy (SRS) using the CyberKnife device; in 19 cases, remote radiation therapy. In 24 cases, a chemotherapeutic component was added in addition to radiation treatment. Results: Mean time to relapse was 23 months. The median overall survival (OS) for all patients was 35 months. (DI 26.2–43.7). Indicators of 1-year OS — 85.6 %; 3-year-old — 44.1 %, 5-year-old — 26.5 %. Depending on the type of radiation therapy: the highest progression-free survival (PFS) was found with SPLT and combined photon-neutron therapy (SPNT) as in the group of patients with recurrent EH for 15, 17, and AA 24 and 40 months, respectively. Among the patients included in our study, the majority of patients (42 people) had central recurrences (in which 95 % or more of the volume of the recurrent tumor was within 100-95 % of the initial isodose), 6 had marginal relapses (20 to 80 % of the recurrent volume is within the surface of 95 % isodose), and in 2 cases a distant recurrence was recorded (less than 20 % of the recurrent volume was within 95 % of the isodose). Distant recurrences (marginal and distant) occurred within an average of 12 months, while central recurrences were diagnosed on average 26 months after the end of the course of radiation (chemoradiation) treatment. Conclusion: Thus, when analyzing our data, in all patients with continued growth of primary high-grade brain gliomas, the method of choice for a repeated course of radiation therapy is stereotactic radiation therapy or a combined course of photon-neutron therapy, which allows to overcome the existing radioresistance.

Dual Nucleosomal Double-Strand Breaks Are the Key Effectors of Curative Radiation Therapy

Most ionizing radiation produces δ-rays of ≈1 keV that can impart MGy doses to 100 nm3 volumes of DNA. These events can produce severe dual double-strand breaks (DDSBs) on nucleosomes, particularly in dense heterochromatic DNA. This is the most common multiply damaged site, and their probabilities determine the biological effectiveness of different types of radiation. We discuss their frequency, effect on cell survival, DNA repair, and imaging by gold nanoparticle tracers and electron microscopy. This new and valuable nanometer resolution information can be used for determining the optimal tumor cure by maximizing therapeutic effects on tumors and minimizing therapeutic effects on normal tissues. The production of DDSBs makes it important to deliver a rather high dose and LET to the tumor (>2.5 Gy/Fr) and at the same time reach approximately 1.8–2.3 Gy of the lowest possible LET per fraction in TP53 intact normal tissues at risk. Therefore, their intrinsic low-dose hyper-sensitivity (LDHS)-related optimal daily fractionation window is utilized. Before full p53 activation of NHEJ and HR repair at ≈½ Gy, the low-dose apoptosis (LDA) and LDHS minimize normal tissue mutation probabilities. Ion therapy should thus ideally produce the lowest possible LET in normal tissues to avoid elevated DDSBs. Helium to boron ions can achieve this with higher-LET Bragg peaks, producing increased tumor DDSB densities. Interestingly, the highest probability of complication-free cure with boron or heavier ions requires a low LET round-up for the last 10–15 GyE, thereby steepening the dose response and further minimizing normal tissue damage. In conclusion, the new high-resolution DSB and DDSB diagnostic methods, and the new more accurate DNA-repair-based radiation biology, have been combined to increase our understanding of what is clinically important in curative radiation therapy. In fact, we must understand that we already passed the region of optimal LET and need to go back one step rather than forward, with oxygen being contemplated. As seen by the high overkill and severely high LET in the distal tumor and the increased LET to normal tissues (reminding of neutrons or neon ions), it is therefore preferable to use lithium–boron ions or combine carbon with an optimal 10–15 GyE photon, electron, or perhaps even a proton round-up, thus allowing optimized, fractionated, curative, almost complication-free treatments with photons, electrons, and light ions, introducing a real paradigm shift in curative radiation therapy with a potential 5 GyE tumor boost, 25% increase in complication-free cure and apoptotic–senescent Bragg Peak molecular light ion radiation therapy.

Detection of chalcopyrite in digital images of copper ore sample sections

Copper ores are mineral formations of natural origin, the concentration of copper or copper compounds in which is sufficient for their commercial mining. Because of this, copper ores are on the list of minerals that are of strategic importance for the sustainable development of the economy and defense capability of Ukraine. In addition, due to the high thermal conductivity, copper and its alloys are widely used for the manufacture of various types of heat exchangers and radiators. The content of copper in ores usually ranges from 1 to 5%; ores containing less than 0.5% copper are unprofitable for processing at the current level of technology. Mining of copper is of strategic importance, as copper is the main material for the production of cable products and other conductive parts in the electrical industry. The efficiency of technological processes in the mining and industry during the production of copper depends on the quality of ores in relation to the content of minerals that contain copper. Copper ore can be considered a heterogeneous material consisting of two homogeneous phases, one phase is host rock, and the other is copper mineral. Modern image processing techniques have allowed as to automate the identification of minerals in ore samples. Automatic recognition and quantification of minerals using X-Ray tomography, scanning electronic microscope, light microscopy, is one of the most important problems in ore processing systems, as the amount of the minerals in the ore must be determined for further processing. A method of segmentation of colour images of sections of test samples of copper ore is proposed to estimate the percentage content of its components in the section of the tested samples. It is based on the use of chalcopyrite colour features in the HSV model. This colour-based segmentation method is proposed to exploit the average value and distribution of HSV colour components of chalcopyrite in an copper ore image. Segmentation parameters are configured. The experimental results of the segmentation of colour images of copper ore slices by the proposed method are analyzed. The effectiveness of the method is checked using synthesized test images. The method provides an absolute error less than 2.5%.

Fluidized bed reactor for 4-chlorophenol photodegradation via solar and visible radiation using ZnO/g-C3N4/carbon xerogel as a photocatalyst

This study investigates the feasibility of employing a fluidized bed reactor for the degradation of 4-chlorophenol (4CP), considering multiple operational parameters (type of radiation, fresh inlet flow rate and recycle flow rate). The selection of the ZnO/g-C3N4/carbon xerogel as photocatalyst, a choice motivated by the improved charge transfer and increased catalyst activity under visible radiation provided by the presence of carbon xerogel and g-C3N4, was previously determined through tests conducted in a jacketed batch reactor under visible radiation, in which the ternary material efficiency was compared to their constituting counterpart materials. The semiconductors constituting the unary, binary, and ternary materials were chosen based on considerations of availability, sustainability, and abundance in nature. The use of the proposed fluidized bed reactor brings advantages in scalability, distribution of irradiated light and overall costs when compared to commonly used batch reactors, whereas the investigation of the flow parameters involved in such process is of great importance to understand and optimize the efficiency of the pollutant degradation process. Regarding the ternary photocatalyst, X-ray diffractometry (XRD) revealed the presence of zinc oxide's hexagonal crystalline structure. Moreover, additional characterization using Raman spectroscopy, Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive spectroscopy (EDS) confirmed the presence not only of ZnO but also of carbon xerogel and g-C3N4 in the composite. From the photodegradation experiments, it was determined that the optimal fresh inlet flow rate to achieve the best degradation, as well as the recycle flow rate for this purpose, were 0.07 and 25 L h−1, respectively. Mathematical simulations described that the model that best fits the system's behavior considers the specific reaction rate as dependent on the concentration of the catalyst in the medium.

Effects of tissue heterogeneity and comparisons of collapsed cone and Monte Carlo fast neutron patient dosimetry using the University of Washington clinical neutron therapy system (CNTS)

Fast neutron therapy is a high linear energy transfer (LET) radiation treatment modality offering advantages over low LET radiations. Multileaf collimator technology reduces normal-tissue dose (toxicity) and makes neutron therapy more comparable to MV x-ray treatments. Published clinical-trial and other experiences with fast neutron therapy are reported. Early comparative studies failed to consider differences in target-dose spatial conformality between x-ray and neutron treatments, which is especially important for organs-at-risk close to tumor targets. Treatments planning systems (TPS) for high-energy neutrons lag behind TPS tools for MV x-rays, creating challenges for comparative studies of clinical outcomes. A previously published Monte Carlo model of the University of Washington (UW) Clinical Neutron Therapy System (CNTS) is refined and integrated with the RayStation TPS as an external dose planning/verification tool. The collapsed cone (CC) dose calculations in the TPS are based on measured dose profiles and output factors in water, with the absolute dose determined using a tissue-equivalent ionization chamber. For comparison, independent (external) Monte Carlo simulation computes dose on a voxel-by-voxel basis using an atlas that maps Hounsfield Unit (HU) numbers to elemental composition and density. Although the CC algorithm in the TPS accurately computes neutron dose to water compared to Monte Carlo calculations, calculated dose to water differs from bone or tissue depending largely on hydrogen content. Therefore, the elemental composition of tissue and bone, rather than the material or electron density, affects fast neutron dose. While the CC algorithm suffices for reproducible patient dosimetry in fast neutron therapy, adopting methods that consider tissue heterogeneity would enhance patient-specific neutron dose accuracy relative to national standards for other types of ionizing radiation. Corrections for tissue composition have a significant impact on absolute dose and the relative biological effectiveness (RBE) of neutron treatments compared to other radiation types (MV x-rays, protons, and carbon ions).

Single-Cell Radiation Response Scoring with the Deep Learning Algorithm CeCILE 2.0.

External stressors, such as ionizing radiation, have massive effects on life, survival, and the ability of mammalian cells to divide. Different types of radiation have different effects. In order to understand these in detail and the underlying mechanisms, it is essential to study the radiation response of each cell. This allows abnormalities to be characterized and laws to be derived. Tracking individual cells over several generations of division generates large amounts of data that can no longer be meaningfully analyzed by hand. In this study, we present a deep-learning-based algorithm, CeCILE (Cell classification and in vitro lifecycle evaluation) 2.0, that can localize, classify, and track cells in live cell phase-contrast videos. This allows conclusions to be drawn about the viability of the cells, the cell cycle, cell survival, and the influence of X-ray radiation on these. Furthermore, radiation-specific abnormalities during division could be characterized. In summary, CeCILE 2.0 is a powerful tool to characterize and quantify the cellular response to external stressors such as radiation and to put individual responses into a larger context. To the authors knowledge, this is the first algorithm with a fully integrated workflow that is able to do comprehensive single-cell and cell composite analysis, allowing them to draw conclusions on cellular radiation response.

Radiation Therapy in the Last Month of Life: Association With Aggressive Care at the End of Life.

Half of the patients with cancer who undergo radiation therapy do so with palliative intent. To determine the proportion of undergoing radiation in the last month of life, patient characteristics, cancer course, the type and duration of radiation, whether palliative care was involved, and the of radiation with aggressive cancer care metrics. One thousand seven hundred twenty-seven patients who died of cancer between January 1, 2018, and December 31, 2019, were included. Demographics, cancer stage, palliative care referral, advance directives, use of home health care, radiation timing, and survival were collected. Type of radiation, course, and intent were reviewed. Chi-square analysis was utilized for categorical variables, and Kruskal-Wallis tests for continuous variables. A stepwise selection was used to build a Cox proportional hazard model. Two hundred thirty-three patients underwent radiation in the last month of life. Younger patients underwent radiation 67.3 years (SD 11.52) versus 69.2 years (SD 11.96). 42.6% had radiation within two weeks of death. The average fraction number was 5.5. Individuals undergoing radiation were more likely to start chemotherapy within the last 30 days of life, continue chemotherapy within two weeks of death, be admitted to the ICU, and have two or more hospitalizations or emergency room visits. Survival measured from the date of diagnosis was shorter for those undergoing radiation, 122 days (IQR 58-462) versus 474 days (IQR 225-1150). Palliative care consultations occurred later in those undergoing radiation therapy. Radiation therapy in the last month of life occurs in younger patients with rapidly progressive cancer, who are subject to more aggressive cancer care, and have late palliative care consults.

Anti-tumor Effect of High Doses of Carbon Ions and X-Rays during Irradiation of Ehrlich Ascites Carcinoma Cells Ex Vivo.

The effect of carbon ions (12C) with the energy of 400 MeV/nucleon on the dynamics of induction and growth rate of solid tumors in mice under irradiation of Ehrlich ascites carcinoma cells (EAC) ex vivo at doses of 5-30 Gy relative to the action of equally effective doses of X-ray radiation was studied. The dynamics of tumor induction under the action of 12C and X-rays had a similar character and depended on the dose during 3 months of observation. The value of the latent period, both when irradiating cells with 12C and X-ray, increased with increasing dose, and the interval for tumor induction decreased. The rate of tumor growth after ex vivo irradiation of EAC cells was independent of either dose or type of radiation. The dose at which EAC tumors are not induced within 90 days was 30 Gy for carbon ions and 60 Gy for X-rays. The value of the relative biological effectiveness of carbon ions, calculated from an equally effective dose of 50% probability of tumors, was 2.59.

ЗАБОЛЕВАЕМОСТЬ САХАРНЫМ ДИАБЕТОМ 2 ТИПА И РИСК ЕГО ВОЗНИКНОВЕНИЯ У ЛИКВИДАТОРОВ ПОСЛЕДСТВИЙ АВАРИИ НА ЧАЭС, В ТОМ ЧИСЛЕ РАБОТНИКОВ ПРЕДПРИЯТИЙ АТОМНОЙ ПРОМЫШЛЕННОСТИ

Summary: Investigation purposes Diabetes mellitus (DM) occupies the largest share in the structure of endocrine system diseases, nutritional disorders and metabolic disorders, which is currently one of the important priorities of national health systems. Research on certain groups of the population with their own harmful occupational risk factors is relevant. Analysis of the incidence of diabetes mellitus of the second type - T2DM (ICD 10: E11-E11.9) of liquidators of the consequences of the Chernobyl accident ‒ workers of nuclear industry enterprises for 30 years of observation and assessment of the radiation risk of its occurrence. Material and methods: The study includes data from the Industry register of persons exposed to radiation as a result of the Chernobyl accident over a thirty-year period, having a verified dose of external radiation received during work in the 30 km zone of the Chernobyl nuclear power plant, men – 12663 people, 1327, of whom have data on the dose of occupational irradiation. The Poisson process with an intensity parameter was chosen as a statistical model of morbidity. Results: The incidence of T2DM in liquidators of the consequences of the Chernobyl accident was estimated by age and sex groups. On the basis of the obtained file of individual unstratified data, an analytical likelihood function for the Poisson process was constructed and the value of the excess relative risk (ERR) of T2DM incidence was calculated and the nature of the dose dependence of RR was investigated. A cohort epidemiological study of a group of liquidators in 1986–1990 was carried out. over a thirty-year period, depending on the dose, both received during the liquidation of the consequences of the Chernobyl accident, and during professional work with radioactive substances (RS) and sources of ionizing radiation (IRS). Direct estimates of the radiogenic risk of diabetes mellitus are given. Different values ​​of risk were noted when using doses from different types of radiation. There was no significant increase in the risk of disease per dose unit (ERR / Sv). Conclusion: With the aging of the cohort of liquidators, an increase in the incidence of T2DM was noted in both men and women. The results obtained on the assessment of the radiation risk of T2DM at this stage are taken as preliminary, since the use of radiation risk in the development of radiation safety regulations requires a total dose from all types of exposure (professional, emergency, medical, natural).

Development of a model for evaluating the luminescence intensity of phosphors based on the PHITS track-structure simulation

Radiation-induced phosphors are frequently used as radiation detectors to measure dose distributions of swift ions. However, the luminescence intensity per dose of the phosphor at the Bragg peak regions decreases because of the quenching effects. To precisely measure the dose distribution for various radiation types using phosphor detectors, understanding the mechanism of quenching effects, induced by the electrons at the atomic scale, is crucial. In this study, we developed a new microdosimetric model for evaluating the luminescence intensity of phosphors based on the track-structure (TS) modes applicable to arbitrary materials implemented in the Particle and Heavy Ion Transport code System (PHITS). Herein, the two dominant factors for determining the luminescence intensity, such as (1) the energy required to generate an electron-hole pair and (2) their transfer efficiency to the luminescence center, are estimated from the TS mode in PHITS by calculating the number of stopped electrons and their spatial distributions. Using the developed model, we calculated the energy required to generate an electron-hole pair in various phosphors, which revealed a complex dependency on the bandgap energy, the composition, and the density of the material. Furthermore, we simulated the quenching effects of the BaFBr detector by calculating its transfer efficiencies for swift-ion irradiation and compared the simulation results with the corresponding experimental data. The comparison suggested that the density of luminescence centers is an essential parameter of the phosphors to reproduce the experimental quenching effects. The developed model is based on the first-principles calculation without any empirical correction; therefore, it is expected to contribute widely to developing phosphor detectors.

Abstract C020: Racial differences in distress levels among Black and White hormone receptor–positive breast cancer survivors over a 3-year period

Abstract Purpose: The purpose of this study was to determine longitudinal racial variations in distress levels among Black and White women with hormone receptor-positive (HR+) breast cancer. Methods: This is a secondary data analysis from the Women’s Hormonal Initiation and Persistence (WHIP) Study, an observational study of HR+ breast cancer survivors. Data regarding patient demographics (e.g., race, age, education, income) were collected via surveys. Clinicopathologic factors (e.g., stage, type of surgery, chemotherapy, and radiation) and medication type (tamoxifen vs. aromatase inhibitors) were extracted from medical records. The National Comprehensive Cancer Network’s Distress Thermometer was used to capture distress following AET initiation at 4 timepoints (baseline, year 1, year 2 and year 3). Mixed linear effects models were used to identify differences in distress by race over the 3-year period. An unadjusted model included race and time as covariates, whereas the adjusted model controlled for demographics, clinicopathologic factors and medication type. Results: The total sample was comprised of 572 women (410 White and 162 Black). For the unadjusted model, the race by time interaction was not statistically significant (F3, 1002.53= 2.2895, p = 0.077). However, the race by time interaction was statistically significant in the adjusted model (F3, 670.99 = 2.68, p = 0.04576), such that Black survivors experienced increased distress over time compared to White survivors. Age was the only statistically significant covariate as older women had lower distress compared to their younger counterparts (p= 0.01) Conclusion. Black and White HR+ breast cancer survivors had different distress levels over a 3-year period. Over time Black survivors’ distress remained high compared to their White counterparts. It is important to consider these differences, given that Black women have higher breast cancer related morbidity and mortality. Future work should focus on the development of culturally appropriate interventions for distress management in HR+ Black breast cancer survivors. Citation Format: Fariha Tariq, Teletia Taylor, Robert A. Perera, Vanessa B. Sheppard. Racial differences in distress levels among Black and White hormone receptor–positive breast cancer survivors over a 3-year period [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr C020.

Specific Absorbed Fractions for Reference Paediatric Individuals.

The calculation of doses to organs and tissues of interest due to internally emitting radionuclides requires knowledge of the time-dependent distribution of the radionuclide, its physical decay properties, and the fraction of emitted energy absorbed per mass of the target. The latter property is quantified as the specific absorbed fraction (SAF). This publication provides photon, electron, alpha particle, and neutron (for nuclides undergoing spontaneous fission) SAF values for the suite of reference individuals. The reference individuals are defined largely by information provided in ICRP Publication 89. Some improvements and additional data are provided in this publication which define the reference individual's source and target region masses used in the Occupational Intake of Radionuclides (OIR) and Dose Coefficients for Intakes of Radionuclides by Members of the Public series of publications. The set of reference individuals includes males and females at 0 (newborn), 1, 5, 10, 15, and 20 (adult) years of age. The reference adult masses and SAFs provided in this publication are identical to those in ICRP Publication 133 and those used in the OIR series of publications. Computation of SAF values involves simulating radiation transport in computational models which represent the geometry of the reference individuals. The reference voxel phantoms of ICRP Publication 143 are used for photon and neutron transport, and most electron transport. Alpha particle transport is not necessary for large tissue regions as the short range allows for an assumption of full energy absorption (absorbed fraction of unity) for self-irradiation geometries. Additional computational models are needed for charged particles in small, overlapping, or interlaced geometries. Stylised models are described and used for electrons and alpha particles in the alimentary and respiratory tract regions. Image-based models are used to compute SAFs for charged particles within the skeleton. This publication is accompanied by an electronic supplement which includes files containing SAFs for each radiation type in each reference individual. The supplement also includes source and target region masses for each reference individual, as well as skeletal dose-response functions for photons incident upon the skeleton.© 2024 ICRP. Published by SAGE.

Flavonoids and Effective Factors for Protection against Radiations

As the title indicated, this paper studies flavonoids which is a plant composition having the antioxidant characteristics which plays a key role in strengthening the health, decreasing the risk of the diabetes, cancer, and heart diseases. It also focuses on the effective factors for protecting the human beings against the radiations. The data for this study are extracted from different scientific papers published in international journals such as Google Scholar, Scopus, Web of Science, and PubMed. This paper first discusses the damages caused by the ionizing radiations, next, I have talked about the classification of flavonoids. A table containing the data such as the affected animals or cells, the prescribed dosage of the flavonoids, the timing of dosage, the type of radiation, and the result seen on the animals. The result of the study shows that flavonoids truly reduce the adverse effects of the radiations on healthy cells during radio-therapy, accidental radiations, or radiations caused by terrorist attacks on nuclear power plants.