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Ionizing radiation is a major contributor to male infertility by destroying spermatogenesis. Therefore, the need for an effective radio-protective agent is evident. The objective of the present study was to investigate the potential radio-protective effect of ferulic acid (FA) on radiation-induced testicular damage. Mature male Sprague-Dawley rats were either exposed to a single-dose gamma radiation (5 Gy) and/or treated with FA (50 mg/kg), daily for 7 days before irradiation. Sirtuin1 (SIRT1), poly (ADP-ribose) polymerase 1 (PARP1), cytosolic calcium content, and the male reproductive functions (sperm head abnormality) as well as oxidative stress markers were assessed 7 days after irradiation. FA significantly maintained active spermatogenesis. Moreover, it reversed the oxidative stress effects of irradiation. The irradiated group showed marked elevation in both PARP1 expression and activity as well as in cytosolic calcium concentration, whereas SIRT1 activity and expression markedly decreased; in contrast, FA treatment prevented these alterations. Results of histopathological examination of testicular tissues indicated coincidence with those recorded by biochemical analyses. Our data show for the first time that FA had radio-protective effect against radiation-induced testicular damage. It improved spermatogenesis through increasing testicular SIRT1 and testosterone levels and decreasing oxidative stress, PARP1, and cytosolic calcium.

We investigated the gamma radiation response of fiber Bragg gratings (FBGs) inscribed in a few-mode polymer optical fiber. The fiber had a graded-index CYTOP core of 20 µm and XYLEX overclad of 250 µm in diameter. Four FBGs were exposed to gamma radiation during four irradiation sessions at a 5.3 kGy/h dose rate. The FBGs showed a linear Bragg wavelength shift with the received dose with a mean sensitivity of −3.95 pm/kGy at 43 °C. The increased temperature provides a rise in the sensitivity: it reached −10.6 pm/kGy at 58 °C. After irradiation, the FBGs showed partial recovery, which increased with the received dose. Furthermore, the FBG’s reflection power decreased with the dose. This attenuation is mainly due to insertion losses caused by the radiation induced attenuation in the CYTOP fiber. Linear response to the received dose makes CYTOP FBGs attractive for gamma radiation dosimetry. However, temperature dependence of the sensitivity should be compensated in practical applications.

Radiation has a deteriorating effect on humans as well as on the environment depending on its level, although we have all been exposed to natural gamma radiation from birth. The presence of radionuclides in rocks, soil, plants, and water is a major factor behind the natural gamma radiation. The present study deals with the study of natural gamma radiation at Bageshwar, Champawat and Pithoragarh districts of Uttarakhand. It also consists of seasonal variations in gamma radiation and its relationship with altitude and geology. The purpose of this study was to investigate the influence of altitude and geology on natural gamma radiation dose rate data in high-altitude areas of India. The highest gamma radiation value was 444 nSv/h in the summer and 342 nSv/h in the winter. The investigation recorded the gamma radiation up to 2542.20 m altitude, indicating that the geology of the areas is more relevant than the altitude. Few sites in such a high-altitude zone were found to exceed the value of 200 nSv/h, as reported by UNSCEAR. This research is necessary in order to consider the human health and climate changes, both of which are part of the action plan for the United Nation’s Sustainable Development Goals (SDG 3, SDG 13).

We report the response of newly designed 4H-SiC Schottky barrier diode (SBD) detector prototype to alpha and gamma radiation. We studied detectors of three different active area sizes (1 × 1, 2 × 2 and 3 × 3 mm2), while all detectors had the same 4H-SiC epi-layer thickness of approximately µm, sufficient to stop alpha particles up to 6.8 MeV, which have been used in this study. The detector response to the various alpha emitters in the 3.27 MeV to 8.79 MeV energy range clearly demonstrates the excellent linear response to alpha emissions of the detectors with the increasing active area. The detector response in gamma radiation field of Co-60 and Cs-137 sources showed a linear response to air kerma and to different air kerma rates as well, up to 4.49 Gy/h. The detector response is not in saturation for the dose rates lower than 15.3 mGy/min and that its measuring range for gamma radiation with energies of 662 keV, 1.17 MeV and 1.33 MeV is from 0.5 mGy/h–917 mGy/h. No changes to electrical properties of pristine and tested 4H-SiC SBD detectors, supported by a negligible change in carbon vacancy defect density and no creation of other deep levels, demonstrates the radiation hardness of these 4H-SiC detectors.

Polycarbonate (PC) loaded with different filler levels equal to 0.1, 0.2, 0.3, 0.5, 0.75, 1.0, 2.5, 3.5 and 5.0 wt% (weight percent) of bismuth nitrate pentahydrate (Bi(NO3)3·5H2O or BNP) were prepared by dispersion of filler in PC solution, followed by casting. The values of mass attenuation coefficient (μm), effective atomic number (Zeff), effective electron density (Nel), half value layer (HVL) thickness, tenth value layer (TVL) thickness and photon mean free path (MFP or λ) were determined for specific gamma photon energies ranging from 303 up to 1332 keV, both computationally and experimentally. Considerable variation in the radiation attenuation parameters was observed, which is mainly dependent on the energy of incident gamma ray photon and the concentration of BNP incorporated as filler within the PC matrix. Values of the experimentally determined parameters like μm, Zeff and Nel were compared with the computationally estimated values, and they are found to be in good agreement. The results are discussed, taking into consideration our understanding of the interaction of gamma radiation with matter.

Ambient gamma radiation is a key component of environmental radiation monitoring and is strongly modulated by atmospheric and meteorological processes. This study presents a long-term analysis of near-surface gamma radiation measured in Ponta Delgada (São Miguel Island, Azores), integrating continuous observations from the Portuguese National Alert Network for Environmental Radioactivity (RADNET) with meteorological data. The dataset spans more than a decade and includes a documented instrumental upgrade in 2020, which introduced enhanced sensitivity and radionuclide identification capability. Results reveal pronounced variability across daily, seasonal, and interannual timescales. Stepwise level shifts are identified in 2016 and 2020, associated with operational and instrumental modifications, respectively, rather than with changes in environmental radioactivity. Seasonal analysis shows higher gamma radiation values during autumn and winter and lower values in late spring and summer, consistent with precipitation-driven washout and boundary-layer dynamics. Generalized Additive Models (GAMs) highlight precipitation, wind speed, and relative humidity as dominant meteorological drivers acting through non-linear relationships. Overall, the results support the use of ambient gamma radiation as an atmospheric indicator of boundary-layer processes and meteorological modulation in remote maritime environments, extending its role beyond routine environmental surveillance.

Novae are thermonuclear explosions on a white dwarf surface fueled by mass accreted from a companion star. Current physical models posit that shocked expanding gas from the nova shell can produce x-ray emission, but emission at higher energies has not been widely expected. Here, we report the Fermi Large Area Telescope detection of variable γ-ray emission (0.1 to 10 billion electron volts) from the recently detected optical nova of the symbiotic star V407 Cygni. We propose that the material of the nova shell interacts with the dense ambient medium of the red giant primary and that particles can be accelerated effectively to produce π° decay γ-rays from proton-proton interactions. Emission involving inverse Compton scattering of the red giant radiation is also considered and is not ruled out.

Beaches with monazitic sands show high natural radiation, and the knowledge of this radiation is fundamental to simulate the effects of natural terrestrial radiation on biological systems. Monazite-rich sand from a beach in the southeastern Brazil were collected and analyzed by X-ray fluorescence, X-ray diffraction, and magnetic susceptibility. The natural terrestrial radiation of the beach sand showed a positive correlation with the Th and Y elements, which are closely associated with Ce, Nd, Ca, and P, suggesting that this grouping is mainly associated with local natural radiation. Based on the sand characterization, a physical simulator of natural gamma radiation was built with parameters similar to those of the monazite beach sand, considering areas with high natural radiation levels. The simulation revealed that the natural radiation of the monazite sands has a significant effect on reducing the growth of the bacteria strains of E. coli and S. aureus present in the beach sand, with a reduction of 23.8% and 18.4%, respectively.

This study addresses the operational degradation of reinforced concrete structures of buildings and facilities where radioactive materials and waste are handled, if degradation is caused by the joint effect of ionizing radiation from materials (substances) handled and factors affecting the overall aging of concrete, reinforcement bars, and their combination. The research focuses on gamma radiation and its physical, chemical, and mechanical effects, triggering corrosion processes in reinforcement bars during the operation of reinforced concrete structures. Changes in the structural behavior of existing and newly built facilities, where radioactive materials and waste (with a focus on highly and moderately radioactive waste) are handled, must be predictable during the extended period of operation. Prognostication methods and assessment models must be accessible to various specialists, including design engineers. Available software packages and numerical analysis tools are used to devise these methods and models. This research project demonstrates the numerical modeling of electrochemical corrosion triggered by oxygen diffusion in concrete. The COMSOL Multiphysics software package was used to develop a model of a reinforced concrete wall segment. This model was used to analyze and prognosticate electrochemical processes in a structure during its future operation. Results of numerical modeling show that corrosion-triggered changes in the original diameter of reinforcement do not exceed tenths (11.2–12.4%) for the predicted service life of 100 years. Studies should be continued in this direction because such factors as radiolysis, carbonization, radiation heating, and changes in the aggregate can have an adverse effect on structures during their operation.

Glycine plays an essential role in a variety of biological and biochemical processes. As the smallest amino acid, glycine is especially important in studies of prebiotic chemistry and chemical evolution. The behaviour of glycine in aqueous solution under ionizing radiation fields is still not well understood. Understanding the reaction mechanism of glycine in an ionizing radiation environment may provide insights into the complex processes involved in prebiotic chemical synthesis. Such reaction conditions could provide clues about the environmental conditions that might favour the emergence of life. Numerical modelling based on reaction kinetics provides information on the feasibility of the reaction mechanisms. In this work, we developed a numerical model in Python that describes the behaviour of glycine, as prototype compound, in aqueous solution under gamma radiation. The model is based on a variety of reaction kinetics pathways that have been proposed to describe the principal reactions between glycine and the water radicals formed by ionizing radiation. The numerical results are consistent with the experiments of other researchers. We obtained similar numerical solutions from different reaction mechanisms that share the same initial reactions. The results suggest that the primary attack of water radicals on the glycine is the main factor that controls the general decay of the molar concentration of glycine and the secondary reactions do not have a strong influence, even at high doses of nearly 200 kGy. The numerical tests of the models indicate their stability with the changing initial condition of the molar concentration of glycine. This work contributes to the advancement of knowledge regarding the behaviour of glycine in aqueous solutions under ionizing radiation from a kinetic perspective. It also provides insights into their stability under conditions that are difficult to replicate in the laboratory. Finally, this work contributes to the evaluation of appropriate numerical methods for solving the system of stiff differential equations that describe the reaction mechanism of organic molecules under high radiation fields.