Radiation And Environmental Biophysics[JOURNAL]
Sun
200 papers
Optimization radiation shielding for Bi₂O₃-based composites with artificial neural networks.
Alipoor MR, Eshghi M, Razavi R
Radiat Environ Biophys · 2026 May · PMID 42002610 · Publisher ↗
Lead-based shields are toxic, heavy, and inefficient for multi-spectrum radiation protection, creating a need for safer, lighter, and smarter materials. This study addresses this gap by developing novel bismuth oxide-bas...
Lead-based shields are toxic, heavy, and inefficient for multi-spectrum radiation protection, creating a need for safer, lighter, and smarter materials. This study addresses this gap by developing novel bismuth oxide-based composites for broad-spectrum photon shielding. A series of composites were designed, and their performance was evaluated using Geant4 Monte Carlo simulations. An artificial neural network (ANN) model was trained over 120 epochs to predict linear attenuation coefficients (LACs) and validate the simulation data. The composites demonstrated effective shielding performance across an energy range of 0.015–10 MeV. The ANN model achieved high predictive accuracy, with over 95% of LAC predictions within ± 0.2 error units and relative deviations below 0.5% across most energies. The top-performing C-1 composite achieved a radiation protection efficiency of 62.35% at 1.4 MeV and exhibited the lowest half-value layer of less than 0.8 cm at 0.662 MeV and Compton-to-total interaction ratio among all designs. A critical performance enhancement was observed at bismuth’s K-edge (81 keV), where the tenth-value layer plummeted to less than 0.1 mm. In terms of broad-spectrum utility, the composites showed a high mass attenuation coefficient of up to 5.0 cm²/g at 0.1 MeV and maintained a competitive areal density of 824–889 g/cm² compared to lead at 567 g/cm². The findings indicate that these bismuth-based composites are a high-performance, non-toxic alternative to lead, offering effective protection against gamma rays. This work establishes a data-driven framework, combining simulation and machine learning, for the accelerated design of next-generation radiation shielding materials.
Challenges in dosimetry of ultra-high dose rate electron beams for FLASH radiotherapy: an overview.
Aknouch A, El-Ouardi Y, Belhaj OE … +7 more , Oufni L, Semghouli S, Yjjou M, Mouslih S, El Mansouri M, Talbi M, Rachmoune K
Radiat Environ Biophys · 2026 May · PMID 41999511 · Publisher ↗
Ultra-high dose rate (UHDR) electron beams used in FLASH radiotherapy have demonstrated significant potential to improve the therapeutic ratio by reducing radiation-induced toxicity in normal tissues while maintaining tu...
Ultra-high dose rate (UHDR) electron beams used in FLASH radiotherapy have demonstrated significant potential to improve the therapeutic ratio by reducing radiation-induced toxicity in normal tissues while maintaining tumour control. Despite these promising radiobiological outcomes, the implementation of FLASH radiotherapy remains strongly limited by challenges in dosimetry and beam monitoring under UHDR conditions. Conventional dosimetric systems suffer from signal saturation, dose-rate dependence, and limited temporal resolution, leading to significant uncertainties in dose measurements. This paper provides an overview of the technologies currently employed to generate UHDR electron beams for FLASH applications and examines the performance and limitations of existing dosimeters in these extreme irradiation conditions. Emphasis is placed on detector response mechanisms, correction strategies, and experimental methodologies reported in recent literature. Emerging solutions based on novel materials, advanced electronics, and alternative measurement approaches are also discussed. Addressing these dosimetric challenges is essential for ensuring measurement accuracy, improving inter-system reproducibility, and enabling the safe and reliable clinical translation of UHDR electron beam FLASH radiotherapy.
Dosimetric analysis of VMAT-TBI: measurement of organ and junction dose using a whole body anthropomorphic phantom.
Kakade NR, Kumar R, More M … +3 more , Chakrabarty S, Sharma SD, Sapra BK
Radiat Environ Biophys · 2026 May · PMID 41984185 · Publisher ↗
Total body irradiation (TBI) is an essential component of conditioning regimens for hematopoietic stem cell transplantation. Volumetric Modulated Arc Therapy-TBI (VMAT-TBI) has recently emerged as an innovative alternati...
Total body irradiation (TBI) is an essential component of conditioning regimens for hematopoietic stem cell transplantation. Volumetric Modulated Arc Therapy-TBI (VMAT-TBI) has recently emerged as an innovative alternative to conventional TBI that offers improved dose conformity. However, VMAT-TBI introduces junction regions between adjacent fields, making dosimetric verification crucial for ensuring uniform dose delivery. In addition, measurement of organ dose in organs such as brain, eyes, heart, liver, lung, kidney, and spinal cord is important for minimizing acute and late toxicities. The present study aimed at measuring the organ and junction doses using a whole body anthropomorphic phantom (ATOM 701-D, CIRS, Norfolk, Virginia). This phantom includes capsule-containing thermoluminescence dosimeters (TLDs) at multiple positions within organ and field junction. Computed Tomography (CT) images of the phantom were acquired to delineate different organs and the TLD locations. A treatment plan comprising four sub-plans with three junction fields was generated using the Eclipse treatment planning system (Version 17.0, Varian Medical Systems, Palo Alto, CA) to deliver 95% of the prescription dose to 95% of the planning target volume (PTV). Conformal dose coverage of the PTV was achieved and organ doses were within acceptable tolerances. The percentage deviation between doses measured with the TLDs and those calculated with the treatment planning system (TPS) with respect to prescription dose was evaluated at 38 positions (26 within various organs and 12 within junction regions). Percentage deviations at the 12 positions in the junction regions and 21 positions within organs were within ± 5% with a slightly higher differences ranging from − 6.72% to 7.43% at remaining five positions. The results demonstrate the effectiveness of VMAT-TBI as a promising alternative to conventional TBI, for hematopoietic stem cell transplantation.
Polymeric tissue substitutes for In-vivo radionuclide monitoring phantoms: state of the art and future directions.
Nara V, Joshi S, Panda M … +2 more , Annalakshmi O, Srinivas CV
Radiat Environ Biophys · 2026 May · PMID 41984184 · Publisher ↗
Phantoms are anthropomorphic models used for the quantitative assessment of internal radiation exposure. They are constructed from tissue-equivalent polymeric materials designed to replicate the radiological properties o...
Phantoms are anthropomorphic models used for the quantitative assessment of internal radiation exposure. They are constructed from tissue-equivalent polymeric materials designed to replicate the radiological properties of real human tissues. This article presents an overview of the different types of phantoms employed in in-vivo monitoring. The fundamental requirements of tissue-equivalent materials and the principles underlying the formulation of tissue substitutes are discussed. A comprehensive review of polymeric tissue substitutes developed over the past five decades is provided, covering their production, physical and radiological properties in comparison with real human tissues, as well as the associated challenges and remaining limitations. Practical steps required to address these gaps are also highlighted. The article concludes with perspectives on future directions in phantom design and the development of advanced next-generation phantoms.
DNA sequence-dependent damage by Auger electrons in fibroblast cell: a geant4-DNA study.
Azizi Ganjgah A, Taherparvar P
Radiat Environ Biophys · 2026 Mar · PMID 41915212 · Publisher ↗
This research investigated the effects of DNA sequence on the single strand breaks (SSBs) and double strand breaks (DSBs) of DNA induced by Auger electron-emitting radionuclides in an atomic model of fibroblast cells usi...
This research investigated the effects of DNA sequence on the single strand breaks (SSBs) and double strand breaks (DSBs) of DNA induced by Auger electron-emitting radionuclides in an atomic model of fibroblast cells using the Geant4-DNA toolkit. For this, two cells (C1 and C2) and their nuclei (N1 and N2), defined as homogeneous ellipsoids of liquid water of unit density, were considered. An atomic DNA model constructed in the Geant4-DNA toolkit was placed inside N1 and N2. While N1 solely consisted of Cytosine-Guanine (C-G) sequences, N2 contained a novel DNA sequence (damage-specific DNA-binding protein 2 (DDB2)), which has not been investigated to date. This sequence includes nucleotide motifs such as C-G, Adenine-Thymine (A-T), Guanine-Cytosine (G-C), and Thymine-Adenine (T-A). The total numbers of direct and indirect SSBs, DSBs, and hybrid DSBs (HDSBs), caused by five widely-used Auger electron-emitting radionuclides, including 99mTc, 111In, 123I, 125I, and 201Tl were quantified at the cellular level. The results show that the total DNA damage, from greatest to least, corresponds to 201Tl, 125I, 123I, 111In, and 99mTc. In addition, incorporating DDB2 base pairs (bp) into the DNA sequences increased the DNA damage by approximately 31% compared to the case with only C–G bp. The findings of the present study indicate that 201Tl and 125I, due to their higher decay yields of sub-1 keV electron emissions (enabling highly localized energy deposition within the DNA strands), are more effective candidates for inducing DNA strand breaks in a single tumour cell compared to 123I, 111In, and 99mTc.
Monte Carlo simulation of uveal melanoma treatment by ocular plaque brachytherapy using gold nanoparticles.
Moeini SM, Sina S, Rafiepour P … +1 more , Siavashpour Z
Radiat Environ Biophys · 2026 Mar · PMID 41879985 · Publisher ↗
Uveal melanoma is a serious ocular disease that can be fatal. One of its treatment methods involves the use of radioactive seeds, which are temporarily attached to a plaque and placed on the eye. The dose distribution ar...
Uveal melanoma is a serious ocular disease that can be fatal. One of its treatment methods involves the use of radioactive seeds, which are temporarily attached to a plaque and placed on the eye. The dose distribution around the seeds used in ocular plaques strongly depends on the seeds' structure and the ocular plaque's design. Recently, there has been a high interest in using gold nanoparticles (GNPs) as a biocompatible and non-toxic dose enhancer in cancer treatment via ionizing radiation. This study used the Monte Carlo code GATE 9.1 to calculate the dose distribution in the tumour and the eye components with and without the presence of GNPs using I, Pd, and Cs seeds. A 14 mm Collaborative Ocular Melanoma Study (COMS) plaque was simulated, and dosimetry parameters such as depth dose, lateral dose, and Dose-Volume Histogram curves for various eye components and the tumour were obtained. In the next step, GNPs with several concentrations of 5-30 mgAu/g were added to the tumour chemical composition, and the Dose Enhancement Factor for each seed in the presence of GNPs was calculated. The results show that the average doses received by the different eye structures and the tumour vary depending on the seed model. The tumour apex dose increases with increasing concentration of GNPs within the tumour volume, hence reducing the irradiation time. Cs shows the highest dose enhancement, with an increase ranging from 33.87% at 5 mgAu/g to 170.45% at 30 mgAu/g for the tumour apex and from 71.51% at 5 mgAu/g to 377.23% at 30 mgAu/g for the tumour, compared to I and Pd. Furthermore, GNPs decreased the dose delivered to surrounding eye components, particularly for Pd brachytherapy, where the lens has the greatest reduction in dose among all eye components, ranging from 7.57% at 5 mgAu/g to 33.27% at 30 mgAu/g.
ANFSq-Net: Adaptive neuro fuzzy inference system for lung cancer detection and severity level classification using CT image.
Raju S, Venkateswara Rao PV
Radiat Environ Biophys · 2026 Mar · PMID 41843123 · Publisher ↗
The high mortality rate of lung cancer worldwide is largely attributed to its late-stage diagnosis. Assessing lung cancer severity promptly plays a vital role in guiding treatment decisions and enhancing patient survival...
The high mortality rate of lung cancer worldwide is largely attributed to its late-stage diagnosis. Assessing lung cancer severity promptly plays a vital role in guiding treatment decisions and enhancing patient survival rates. This study introduces an Adaptive Neuro-Fuzzy SqueezeNet (ANFSq-Net) framework for lung cancer detection and severity level classification using Computed Tomography (CT) images. The proposed method integrates the strengths of the Adaptive Neuro-Fuzzy Inference System (ANFIS) and SqueezeNet, supported by fractional calculus (FC) regression, to enhance feature adaptability, reduce computational complexity, and improve learning efficiency. To preprocess the CT images, noise is removed with a bilateral filter, followed by lung lobe segmentation through a Conditional Generative Adversarial Network (CGAN). Key features such as Local Ternary Pattern (LTP), homogeneity, and entropy are extracted for accurate classification of lung cancer into mild, moderate, and severe levels. The ANFSq-Net model achieves excellent performance metrics, including 94.876% accuracy, 96.877% sensitivity, 92.987% specificity, 93.988% precision, and a 95.411% F1-score. It is concluded that the combined application of ANFIS, SqueezeNet, and FC regression enables precise and efficient classification performance.
Towards harmonized global approaches to NORM regulation: review of practices and policy perspectives.
Verma GP, Patra AC, Dubey KA … +2 more , Jha SK, Aswal DK
Radiat Environ Biophys · 2026 Mar · PMID 41817690 · Publisher ↗
Exposure to natural radioactive sources, particularly those involving Naturally Occurring Radioactive Material (NORM), poses a significant concern for policymakers, the public, industry, and researchers worldwide. As hum...
Exposure to natural radioactive sources, particularly those involving Naturally Occurring Radioactive Material (NORM), poses a significant concern for policymakers, the public, industry, and researchers worldwide. As human dependence on NORM-related mineral industries grows, achieving a harmonized approach to managing NORM exposure becomes increasingly crucial, especially given the large-scale international trade of minerals and raw materials. A unified international approach (like IAEA guidance or HERCA’s, 2021 recommendations) would not only enhance safety but also support smoother global trade and resource sustainability. This paper addresses the inconsistencies in current global regulations governing radiological risks to the public and the environment. It examines the various approaches adopted by national and international regulatory bodies and identifies the inconsistencies that hinder progress toward global harmonization. These regulatory discrepancies create uncertainty for industries and disrupt the free trade of NORM-related minerals. The paper also discusses how the development of standards and regulations heavily relies on dose modelling assessments, particularly where facility-specific data is lacking for NORM industries outside the nuclear sector. This analysis highlights the current regulatory landscape in the mineral processing industry and its impact on public exposure to NORM.
Comment on "Direct radiation damage to human tooth under IMRT for head and neck cancer" by Tamahara and Kouketsu.
Topkan E, Somay E, Bascil S … +1 more , Selek U
Radiat Environ Biophys · 2026 Mar · PMID 41805872 · Publisher ↗
We found the article by Tamahara and Kouketsu (Radiat Environ Biophys 2025. https://doi.org/10.1007/s00411-025-01180-w ) interesting because it examined the direct physicochemical effects of therapeutic irradiation on hu...
We found the article by Tamahara and Kouketsu (Radiat Environ Biophys 2025. https://doi.org/10.1007/s00411-025-01180-w ) interesting because it examined the direct physicochemical effects of therapeutic irradiation on human dental hard tissues as a possible non-salivary cause of radiation-related caries (RRC). The authors investigate a clinically significant and mechanistically fascinating question, utilizing a controlled in vitro approach to analyze radiation-induced modifications in enamel and dentin. The research provides comprehensive information on microhardness, calcium release, collagen autofluorescence, and localized pH variations following irradiation. Nonetheless, specific methodological and interpretation concerns significantly impact the robustness and breadth of the authors’ conclusions, necessitating further scrutiny.
Rebuttal to the Correspondence on "Direct radiation damage to human tooth under IMRT for head and neck cancer: physicochemical evidence supporting a non-salivary mechanism for radiation-related caries".
Tamahara T
Radiat Environ Biophys · 2026 Mar · PMID 41801429 · Publisher ↗
Abstract loading — click title to view on PubMed.
Assessment of radiotherapy effect and toxicity using tissue-associated DNA methylation markers in cell-free DNA: a study on prostate cancer.
Bahtiyar N, Mermut O, Firtina S … +6 more , Ozaydin A, Suleymanova A, Isikgil B, Onaran İ, Isikgil B, Onaran İ
Radiat Environ Biophys · 2026 Mar · PMID 41790195 · Full text
This study aimed to evaluate tissue-associated circulating cell-free DNA (cfDNA) as indicators of radiotherapy-related effects and treatment-associated toxicity in prostate cancer. In addition, inter-individual variabili...
This study aimed to evaluate tissue-associated circulating cell-free DNA (cfDNA) as indicators of radiotherapy-related effects and treatment-associated toxicity in prostate cancer. In addition, inter-individual variability in these markers and their responses to radiotherapy-induced cystitis and rectitis were investigated. The DNA methylation status of six tissue-associated genes representing the prostate (KLK3, TGM4), colon (MUC2, MS4A12), and bladder (UPK2, DHRS2) was analyzed in serum-derived cfDNA using methylation-sensitive melting curve analysis (MS-MCA). Five of the six analyzed genes demonstrated significantly higher relative DNA levels in patients with prostate cancer compared with controls. Radiotherapy did not significantly alter the relative DNA levels of these tissue-associated genes. However, cfDNA fragmentation was significantly increased in the post-treatment group compared to the pre-treatment group. Notably, 79-bp DNA fragments were significantly more abundant than 230-bp fragments. In the post-treatment group, no significant correlations were observed between cfDNA fragmentation and the relative DNA levels of most targets, except for an association between the 230-bp fragment and TGM4 relative DNA levels. These findings suggest limited coupling between cfDNA fragmentation patterns and tissue-associated cfDNA release. Marked inter-individual variability in cfDNA methylation signatures was observed across all examined CpG-containing regions except UPK2. This variability did not change significantly following radiotherapy and may therefore limit the utility of these assay regions for monitoring individual radiation-induced tissue damage. Furthermore, no significant changes in methylation profiles of colon- or bladder-associated genes were detected in patients who developed radiotherapy-induced rectitis or cystitis. Overall, increased cfDNA fragmentation following radiotherapy and substantial inter-individual variability in methylation profiles across tissue-associated regions may mask tissue-associated cfDNA signals, thereby complicating the assessment of radiation-induced tissue damage.
Prolonged low-dose neutron irradiation induces late cellular and molecular impairments in the mice hippocampus and causes cognitive deficit.
Rodina AV, Zhirnik AS, Vysotskaya OV … +3 more , Smirnova OD, Cheshigin IV, Moskaleva EY
Radiat Environ Biophys · 2026 Mar · PMID 41784635 · Publisher ↗
Late effects of prolonged low-dose neutron exposure on the brain function remain poorly studied. We analyzed the content of neural progenitor cells, microglia and astrocytes, the number of PSD-95 puncta, the expression l...
Late effects of prolonged low-dose neutron exposure on the brain function remain poorly studied. We analyzed the content of neural progenitor cells, microglia and astrocytes, the number of PSD-95 puncta, the expression level of pro- and anti-inflammatory cytokines in the hippocampus, and long-term spatial and recognition memory in conventional (CV) and specific pathogen-free (SPF) mice 2 months after prolonged neutron irradiation at doses of 0.05 (1 day) and 0.5 Gy (10 day). Neurogenesis was intact in all mice. The level of PSD-95 was increased only in CV mice irradiated at 0.05 Gy. In CV mice, an increase in the number of microglia was recorded at both doses and astrocytes at 0.05 Gy; in SPF mice, both microglia and astrocytes increased only after irradiation at 0.5 Gy. The expression of TNFα and IL-1β increased in all irradiated mice; the expression of TGFβ decreased in CV mice irradiated at 0.5 Gy. These findings suggest that the severity of neuroinflammation in irradiated CV mice was higher than in SPF mice. Conventional analysis of escape latencies in the Morris water maze (MWM) revealed an intact spatial memory in both groups, while analysis of the swimming strategies demonstrated spatial reference memory deficits in CV mice irradiated at 0.05 Gy and in SPF mice irradiated at 0.5 Gy. Novel object recognition (NOR) assay demonstrated decreased recognition index only in CV mice (both doses). Thus, the housing conditions of animal before expose affect the neuroinflammation level and cognitive impairment late after prolonged low-dose neutron irradiation.
Legal regulatory frameworks of radon spas in central Europe.
Mihók P, Liptáková K
Radiat Environ Biophys · 2026 Mar · PMID 41706174 · Full text
This study synthesises publicly available information on legal regulatory frameworks that explicitly or implicitly govern radon spa designation and/or identification in six Central European countries: Austria, the Czech...
This study synthesises publicly available information on legal regulatory frameworks that explicitly or implicitly govern radon spa designation and/or identification in six Central European countries: Austria, the Czech Republic, Germany, Hungary, Poland, and Slovakia. Employing analytical and comparative methods in Social Sciences and Humanities research, this study examines official documents, legal norms, and academic literature to address gaps in understanding radon spa regulation within, and partially beyond, the context of the RadoNorm project. Findings reveal substantial disparities in legally established thresholds distinguishing medicinal and non-medicinal bathing waters based on radon concentrations, ranging from as little as 74 Bq/L in Poland (and potentially only 37 Bq/L in Hungary) to as high as 1,500 Bq/L in the Czech Republic, with intermediate values of 370 Bq/L in Austria and 666 Bq/L in Germany and Slovakia. These pronounced differences present significant challenges for cross-national comparative research and broader conceptualisation efforts concerning radon spa academic definitions. As an incidental finding, this study also identifies varying approaches to workplace safety regulations for spa employees, with Austria and Germany following one approach and the Czech Republic another. Overall, the study contributes to the dissemination of RadoNorm project findings concerning the complexity of the so-called ‘radon spa controversy’, in which radon is framed negatively in public health discourse regarding indoor exposure, yet positively in spa treatment contexts. The findings emphasise the need for interdisciplinary research covering comprehensive medical evidence to understand the rationale behind the divergent regulatory frameworks identified.
Protective effect and results of glutamine and partially hydrolyzed Guar gum on rats with experimental radiation enteritis.
Aydın E, Bolat L, Aba M … +6 more , Yavuz B, Öztürk ÖG, Erdoğan KE, Andiç F, Rencüzoğulları A, Eray İC
Radiat Environ Biophys · 2026 Mar · PMID 41706173 · Full text
The aim of our study is to evaluate the effects of glutamine, partially hydrolyzed guar gum and combined glutamine and partially hydrolyzed guar gum form in rats with experimental radiation enteritis by histopathological...
The aim of our study is to evaluate the effects of glutamine, partially hydrolyzed guar gum and combined glutamine and partially hydrolyzed guar gum form in rats with experimental radiation enteritis by histopathological, immunohistochemical and biochemical measurements. 64 Wistar albino rats with an average weight of 220-280 g were used in the study. 1st group only took water, 2nd group only took glutamine, 3rd group only took partially hydrolyzed guar gum, 4th group took partially hydrolyzed guar gum with glutamine, 5th group took only radiotherapy, 6th group took radiotherapy with glutamine, 7th group took radiotherapy with partially hydrolyzed guar gum and 8th group took radiotherapy, glutamine and guar gum. Partially hydrolyzed guar gum was given with radiotherapy, and glutamine and guar gum were given together with radiotherapy in the 8th group. All rats were weighed on the first, seventh and tenth days. On the tenth day, the rats were sacrificed and their clinical status, biochemical, histopathological and immunohistochemical parameters in the terminal ileum were evaluated. Differences between groups were compared statistically. All groups were compared in terms of crypt length, villus height, crypt abscess, congestion, intraepithelial lymphoid infiltration, stool consistency, myeloperoxidase, malondialdehyde, caspase-3% and tumor necrosis factor alpha mean, and statistical significance was observed (p < 0.05). Weight% difference in rats was statistically significant between groups (p < 0.05). Interleukin-10 values were not statistically significant between groups (p > 0.05). In paired comparisons, there was a statistically significant difference between the control group and the group with radiation enteritis in terms of biochemical, histopathological, immunohistochemical and clinical parameters (p < 0.05). There was no statistically significant difference between the 5th group and 6th group, 7th group and 8th groups in terms of biochemical, histopathological, immunohistochemical and clinical parameters (p > 0,05). The result suggest that glutamine, partially hydrolyzed guar gum and combination therapy may not have a protective effect on radiation enteritis.
Dosimetry of Cs Liquid-filled intracavitary balloon brachytherapy for enhanced treatment planning: utilizing TL dosimetry (TLD) and Monte Carlo calculation.
Kazemi A, Sardari D, Poorbaygi H … +2 more , Hadadi A, Sheibani S
Radiat Environ Biophys · 2026 Mar · PMID 41677808 · Publisher ↗
An intracavity balloon filled with Cs liquid was investigated to be used in brachytherapy, particularly for the treatment of glioblastoma multiforme (GBM), with a reference of 40-60 Gy at a depth of 1 cm. The dosimetric...
An intracavity balloon filled with Cs liquid was investigated to be used in brachytherapy, particularly for the treatment of glioblastoma multiforme (GBM), with a reference of 40-60 Gy at a depth of 1 cm. The dosimetric characteristics of the liquid Cs, as a low-energy photon source for brachytherapy, were assessed. For this, thermoluminescence dosimetry was used for experimental validation, while Monte Carlo calculations were performed to evaluate dose rate distributions for treatment planning. To prepare the Cs solution, natural BaCO was used as a target irradiated in a thermal neutron flux of 3.5 × 10 n/cm/s at the Tehran Research Reactor (TRR), and the separation of Cs with a radionuclide purity of 99% was confirmed using a radiochemical method. A well counter was employed to measure the activity of the Cs solution. The dosimetric measurements were conducted using a newly designed phantom in the form of a hollow sphere, as well as a water tank and thermoluminescence dosimeters (TLDs). The results were utilized to validate the accuracy of the dose distribution simulated with the MCNP5 Monte Carlo radiation transport code and a volumetric dose algorithm for predicting dose to water. The ± 8% agreement obtained between TLD measurements and MCNP5 simulations (with an uncertainty of ± 12.3%) confirms the validity of the model. The calculated dose rates in water and brain tissue were 0.0127 Gy/h and 0.0131 Gy/h at a reference depth of 0.5 cm per 37MBq, respectively. To calculate the activity relative to the balloon volume, two equations were deduced for volumes below and above 15 cm. The results indicate that the validated dose rate can be used to develop a treatment planning method including a liquid Cs source for brachytherapy applications.
Treatment planning parameters in intensity modulated radiotherapy for prostate cancer and their dosimetric impact: a study using Monaco TPS.
Coc FL, Marcu LG
Radiat Environ Biophys · 2026 Mar · PMID 41665669 · Publisher ↗
This study aimed to determine the most appropriate treatment planning solution for prostate cancer radiotherapy by analyzing the effect of planning parameters on dosimetric outcome. Four volumetric modulated arc therapy...
This study aimed to determine the most appropriate treatment planning solution for prostate cancer radiotherapy by analyzing the effect of planning parameters on dosimetric outcome. Four volumetric modulated arc therapy (VMAT) / intensity modulated radiation therapy (IMRT) plans were created for each of the 20 patients included in the study, using minimum segment width (MSW) of 0.5, 1.0, 1.5, and 2.0 cm. All prostate plans underwent "Fluence Smoothing" on "High", while plans using MSW = 1.0 were reoptimized with both "Low" and "Medium" settings. All plans met the planning objectives. MSW = 0.5 resulted in better tumour coverage (by over 0.3 Gy), enhanced conformity and better sparing for the majority of organs at risk (OARs). However, this small MSW was associated with a notable increase in monitor units (MUs) (by over 300), control points (CPs) (by over 83) and delivery time (DT) (by over 0.88 min). The most significant impact of reduced fluence smoothing was observed in parameters such as MUs (reduced by over 53) and DT (reduced by over 0.15 min), which improved gamma passing rate (GPR). In the context of dosimetric outcomes, variations in fluence smoothing had minimal effect on the dose distribution to the planning target volume and most OARs. It is concluded that clinically acceptable dose distributions were achieved across all segment widths and fluence smoothing levels. However, using a 1.0 cm MSW with medium-to-high fluence smoothing provided a favourable balance between plan quality, delivery accuracy and efficiency in prostate cancer, without compromising dosimetric outcomes.
Southern ural studies and their input to the work of ICRP.
Ulanowski A, Laurier D, German O
Radiat Environ Biophys · 2026 Mar · PMID 41661285 · Publisher ↗
Since the late 1940s, the Southern Urals region in the Russian Federation hosts nuclear facilities, which operations provided substantial amount of information on impact of occupational and public exposures to ionising r...
Since the late 1940s, the Southern Urals region in the Russian Federation hosts nuclear facilities, which operations provided substantial amount of information on impact of occupational and public exposures to ionising radiation. The International Commission on Radiological Protection (ICRP) recognises the joint Russia-USA radiation studies in the Southern Urals as globally significant contributions to the science of radiological protection and systematically uses their outcomes in the work of the ICRP Committees 1 and 2. For the ICRP Committee 1, results of the studies contribute to improved understanding of biological mechanisms of radiation effects and help modelling radiation-attributed health risks. For the ICRP Committee 2, the studies provide valuable data for development and validation of dose assessment methods and reference data. Together, the Southern Urals radiation studies help to develop and validate evidence-based scientific recommendations, thus supporting the continuing advancement of the radiological protection practice worldwide.
Transfer of sediment-derived carbon into aquatic plants for C biosphere assessment.
Majlesi S, Ullah S, Shirani Z … +4 more , Pumpanen J, Salminen-Paatero S, Akkanen J, Ikonen ATK
Radiat Environ Biophys · 2026 Mar · PMID 41642344 · Full text
Among the released radionuclides from nuclear power plants and radioactive waste repositories, C is of great importance. Continuous discharges of C from nuclear industries, the risk of uncontrolled releases, and possible...
Among the released radionuclides from nuclear power plants and radioactive waste repositories, C is of great importance. Continuous discharges of C from nuclear industries, the risk of uncontrolled releases, and possible leaking from facilities may cause a threat to the biosphere. Because of high mobility and a long half-life of C, it has great potential to be released into aquatic ecosystems and to be assimilated by aquatic plants. However, the amount of C incorporated into organic matter and hydrophytes is largely unknown. In this study, the uptake of carbon from sediment into aquatic plants was investigated in a microcosm experiment. The study was carried out based on the natural difference in the isotopic signature of C between the 8000-year-old peat and more enriched sources (water and atmosphere). The two-pool isotope mixing model was applied to determine the relative contribution of each source (sediment vs. air/water) to the hydrophytes. The results indicated the highest contribution of sediment-derived carbon to the free-floating Lemna minor (up to 60%), followed by submerged Littorella uniflora (15-17%) and the emergent species, Stachys palustris and Lysimachia nummularia (up to 10%). Despite the contribution of sediment-derived C to their C source, the hydrophytes incorporated less than 2% of their total C from sediment. The results also indicated the importance of floating plants in more efficient uptake of sediment-derived C available in water column or the air. Furthermore, no significant difference was found in the transfer of sediment-derived C between the roots and the leaves within the species.
Memantine mitigates radiation-induced cognitive impairment by modulating AKT/GSK3β signaling.
Fu H, Feng J, Zhang X … +5 more , Tian L, Sun S, Bo H, He C, Wang X
Radiat Environ Biophys · 2026 Mar · PMID 41636819 · Publisher ↗
Memantine hydrochloride (MH), primarily employed in the clinical treatment of Alzheimer’s disease (AD), has been reported to exert beneficial effects on radiation-induced cognitive impairment; however, its underlying mec...
Memantine hydrochloride (MH), primarily employed in the clinical treatment of Alzheimer’s disease (AD), has been reported to exert beneficial effects on radiation-induced cognitive impairment; however, its underlying mechanisms have not been fully elucidated. In this study, a mouse model of radiation-induced injury was established. ICR(Institute of Cancer Research) mice were divided into six groups: control, 8 Gy irradiation, prophylactic 20 mg/kg + 8 Gy, prophylactic 40 mg/kg + 8 Gy, post-irradiation 8 Gy + 20 mg/kg, and post-irradiation 8 Gy + 40 mg/kg. Behavioral assessments indicated that ionizing radiation induced spatial cognitive deficits, which were ameliorated by MH administration. Morphological analyses revealed neuronal damage, synaptic injury, and demyelination in the hippocampal dentate gyrus (DG) region, which were markedly attenuated following MH treatment. Western blot analysis demonstrated that radiation upregulated dopamine D2 receptor (D2R) and β-arrestin 2 expression, suppressed PP2A expression, promoted AKT dephosphorylation, and led to GSK3β overactivation, along with increased expression of MBP and PLP1—potential mechanisms underlying radiation-induced cognitive impairment. MH administration downregulated D2R and β-arrestin 2, enhanced PP2A-AKT interaction, reduced GSK3β activity, and upregulated MBP and PLP1 expression. Notably, prophylactic administration conferred greater neuroprotection than post-irradiation treatment. These findings provide preliminary insight into the protective mechanisms of MH against radiation-induced cognitive impairment and offer a basis for future studies in radiation neuroprotection.
Biospecimens from plutonium-exposed workers: an update on the status of the Russian human radiobiological tissue repository.
Loffredo CA
Radiat Environ Biophys · 2026 Mar · PMID 41636818 · Publisher ↗
Founded in 1999 under the bilateral U.S.-Russian Agreement on International Cooperation for Minimization of the Effects of Prolonged Radiation Exposure, the Human Radiobiological Tissue Repository (HRTR) at the Southern...
Founded in 1999 under the bilateral U.S.-Russian Agreement on International Cooperation for Minimization of the Effects of Prolonged Radiation Exposure, the Human Radiobiological Tissue Repository (HRTR) at the Southern Urals Biophysics Institute aims to collect, store, annotate, and disburse biological materials from individuals occupationally exposed to ionizing radiation, to support scientific investigations of the effects of radiation exposure on human health. In compliance with international best practices guidelines, the RHTR has assembled a collection of over 100,000 biospecimens donated by workers of the Mayak Production Association, and by non-occupationally exposed persons living in the same city. Included in its biobanks are fully annotated autopsy tissues stored in formalin, formalin-fixed paraffin-embedded tissue blocks, microscope slides, frozen surgical tissues, whole blood and blood components, and genomic DNA from parental-offspring triads. The biorepository's database contains information on radiation dose characteristics, occupational history, non-radiation risk factors, detailed medical history, and social and demographic characteristics of each donor. This comprehensive approach has resulted in a unique resource that has supported both molecular and non-molecular studies of radiation health effects.
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