Gamma-ray Irradiation Research Articles

Long-term effects of continuous low dose-rate gamma-ray irradiation on mouse hematopoietic cells.

The present work investigates the long-term effects of continuous low dose-rate (20mGy/day to total doses of 1-8Gy) gamma-ray exposure on the hematopoietic cells of specific pathogen-free C3H/HeN mice. Peripheral white blood cell (WBC) counts decreased on days 206, 471, and 486, with no significant changes in red blood cell (RBC) and platelet (PLT) counts. The number of colony forming units (CFU-S and CFU-GM) in the bone marrow and spleen from irradiated mice decreased with increasing total dose on day-12 and day-7. The decrease in bone marrow CFU-S persisted throughout the 400-day irradiation period and did not show any recovery up to 210days postirradiation. These findings suggest that the effects of low-dose-rate (LDR) radiation on the hematopoietic system remain long after the 400-day irradiation was completed. Further investigation showed no significant difference in life spans of non-irradiated W/Wv (c-kit-deficient) mice inoculated with hematopoietic stem cells from irradiated (20mGy/day for 400days) or nonirradiated wild-type mice. These results suggest that the effects of continuous low-dose-rate irradiation are more pronounced in hematopoietic stromal cells than in HSCs themselves.

Investigation of Gamma-Ray Radiation Shielding Properties of Zinc Borate and Paraffin Filled Sheep Wool Biopolymer Composites: Experimental and Theoretical Analysis

Investigation of Gamma-Ray Radiation Shielding Properties of Zinc Borate and Paraffin Filled Sheep Wool Biopolymer Composites: Experimental and Theoretical Analysis

Gamma ray irradiation on Swiss cheese estates (Monstera adansonii): growth, development, and variation

Purpose Swiss Cheese (Monstera adansonii) is an ornamental plant valued for its exotic leaves with openings and for the variety of colors. The technique of controlled exposure to gamma radiation was investigated to induce variegation (color change) in the leaves of this plant. Materials and methods Monstera adansonii cuttings were irradiated with different doses of radiation with 60Co gamma rays (0, 1, 5, 10, 15, and 20 Gy) and evaluated for size, color, health, and growth. Results Cuttings irradiated with 1 and 5 Gy exhibited temporary variegation in leaf color, but did not maintain these characteristics over time. Cuttings with higher doses of radiation (10, 15, and 20 Gy) did not survive well and showed a reduction in growth, number of leaves, health, and sprouting rate. Conclusions This research concludes that gamma radiation can affect the development of cuttings and shows the potential to induce variegation at lower doses, but more studies and prolonged observation are needed to determine whether this technique can produce variegation in a consistent and lasting way in M. adansonii. Therefore, although promising initial results have been observed, it is premature to state that gamma radiation is an effective method for inducing variegation in this plant.

RAD50 Deficiency and Its Effects on Zebrafish Embryonic Development and DNA Repair Mechanisms

The MRE11-RAD50-NBS1 (MRN) complex is essential in detecting, signaling, and repairing DNA double-strand breaks (DSBs), thus maintaining genomic integrity. Mutations in RAD50 are linked to severe conditions such as microcephaly, mental retardation, and growth retardation in humans. This study investigates the developmental impact of RAD50 protein disruption in zebrafish embryos. Zebrafish embryos were treated with MIRIN (35 µM) to inhibit RAD50 and subsequently exposed to gamma-ray irradiation (15 Gy) to analyze the role of RAD50 in managing DNA damage during embryogenesis. Time-point analysis indicated that inhibiting RAD50 and ATM proteins during early embryonic stages (at 1 hpf) leads to increased embryonic mortality and abnormalities. These adverse effects were exacerbated by irradiation, underscoring the critical role of RAD50 in DNA DSB repair. The study concludes that RAD50 deficiencies can lead to embryonic lethality and human deformities due to the inability of tissues to repair DNA DSBs effectively.

Detection of extended gamma-ray emission in the vicinity of Cl Danks 1 and 2

Abstract We report the detection of high-energy gamma-ray emission towards the G305 star-forming region. Using almost 15 years of observation data from Fermi Large Area Telescope, we detected an extended gamma-ray source in this region with a significance of ∼13σ. The gamma-ray radiation reveals a clear pion-bump feature and can be fitted with the power law parent proton spectrum with an index of −2.5. The total cosmic ray (CR) proton energy in the gamma-ray production region is estimated to be the order of $10^{49}\ \rm erg$. We further derived the CR radial distribution from both the gamma-ray emission and gas distribution and found it roughly obeys the 1/r type profile, though a constant profile is not ruled out. This is consistent with other similar systems and expected from the continuous injection of CRs by the central powerful young massive star cluster Danks 1 or Danks 2 in this region. Together with former detections of similar gamma-ray structures, such as Cygnus cocoon, Westerlund 1, Westerlund 2, NGC 3603, and W40, the detection supports the hypothesis that young massive star clusters are CR accelerators.

Improvement of Hygienic and Phytochemical Qualities of Mangosteen (Garcinia Mangostana) Peel by Irradiation

The aim of this study was to compare the effects of gamma ray and x-ray irradiation at different dose levels 95, 10, 15 and 20 kGy) on in mangosteen peel. The antioxidant activities were assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP), while total phenolic contents and antibacterial activities against Staphylococcus aureus and Escherichia coli of 60 % ethanolic mangosteen powder extracts were analyzed. The results indicated that both types of ionizing radiations showed a non-significant decrease in measured parameters with increasing doses. The minimum inhibitory concentration (MIC) values of irradiated mangosteen peel extracted against S. aureus and E. coli ranged from 0.125 to 2.0 mg/mL. The quantity of bioactive compound mangostin determined via high-performance liquid chromatography (HPLC), did not show significant decrease with different irradiation sources and doses. In microbiological aspect, total yeast and mold from both irradiation sources were reduced by 1 log cycle after irradiation at 5 kGy. The irradiation induced color changes corresponding to Hunter color L a b value. X-ray irradiation caused slight color alteration compared to gamma rays. The advantage of x-ray irradiation was that it revealed non-significant changes in b values, whereas gamma irradiation showed the significant change in L, and b values with increasing dosage. The x-ray irradiation at the dose 5 kGy effectively decreased microbial contamination while causing minimal changes to phytochemical qualities and color. HIGHLIGHTS Irradiation at 5 kGy was sufficient to control microbial contamination There were no significant changes in antioxidant activities (DPPH, FRAP), a-mangostin contents, total phenolic contents (TPC) and antibacterial activities: after irradiation up to 20 kGy X-ray irradiation was an excellent alternative to gamma irradiation for decontamination with a non-significant alteration in b values. GRAPHICAL ABSTRACT

Enhancing Agro Morphological Traits of three Unique Traditional Rice Landraces of Chhattisgarh through Gamma Ray-Irradiation

Mutation breeding is a simple and effective technique for generating genetic variation within crops. Mutagens such as Gamma radiation induce changes in their DNA that could lead to the development of new traits, such as improved yield or disease resistance. In the present study, Gamma ray mutagenesis was performed on three traditional rice varieties (Gudma dhan, Dawar dhan, and Lohandi dhan) to identify potentially beneficial mutants with desirable agro-morphological agricultural characteristics. The major constraints to address were their tall statures and weak culms, fewer panicles and tillers, and late maturity. Using a fixed dose of 300 Gy, 35 mutants were identified in Dawar dhan, 33 in Gudma dhan, and 21 in Lohandi dhan. The selected mutants showed an average reduction in plant height that ranged from 42.69% to 33.11%, as compared to their respective landraces. Also, a substantial reduction (ranging from 3.08%-10.55%) in days to 50% flowering was observed. Importantly, these mutants showed an increase in yield of 38.11% (Dawar dhan), 32.63% (Gudma dhan), and 7.0% (Lohandi dhan). These findings demonstrate the utility of mutation breeding through Gamma radiation in alleviating the key constraints inherent to traditional rice landraces.

Effect of FBG Fiber Dosimeter Division in Sensing Capability for Low Radiation Doses

ر A fiber Bragg grating (FBG) as a dosimeter is developed in this simulation study (based on Optisystem 21 software) by dividing its region into five individual regions. The division includes the same properties for all regions, which is a standard SiO2 optical fiber material. In dosimeters, it is convenient to introduce dopants to increase the fiber sensitivity. The new design accepts dopants and can work without such a dopant. Measurements for sensing deflected signals from the FBG sensor confirmed increased sensitivity for low-rate radiation doses in comparison to one bulk region in a traditional fiber dosimeter. The sensitivity of this dosimeter is based on both the FWHM line shape function and the amplitude of the deflected signals. The FBG dosimeter sensor can respond to low-dose radiation in a noticeable manner according to the type of applied simulated effect. Dosimeter body division for multi-regions gives rise to sensitivity in comparison to the traditional bulk region. The measured FWHM from the line-shape function for overall observed signals fluctuates from 0.374 MHz under applied temperature, stress x, y, z, and strain to 0.358, 0.373, 0.3733, 0.368, and 0.3737 MHz, respectively. While this range follows different fitting functions: Sin, Exp.Decay, SinSqu., Exp.Decay3, and GaussAmpl. For last effects, according to measured effect. The same measurements were carried out for signal amplitude variation, with these effects giving a variety of relationships indicating their existing contribution. Results confirmed an efficient tool for use in sensing for low x-ray and gamma ray radiation dose applications versus traditional bulk FBG sensor type.

Measurement of average mass attenuation coefficient of air for 137Cs gamma-ray irradiation beam

Abstract The average mass attenuation coefficient of air for the KRISS 137Cs gamma-ray irradiation beam was measured using a 30 cm-long vacuum-sealable cylindrical column. Six different models of ionization chambers were employed for the measurement. Under ambient room conditions, the average mass attenuation coefficient was found to be (0.0778 ± 0.0012) cm2 g−1 across the six chambers. This coefficient will be used to adjust the variation in air kerma with air density for the 137Cs gamma-ray irradiation beam.

Gamma radiation induced tailoring the structural, optical, surface and mechanical properties of UHMWPE

The present investigation examined how the resultant gamma radiation affected the ultra-high molecular weight polyethylene's (UHMWPE) mechanical, optical, surface, and structural characteristics. Different gamma doses of 75, 150, 250, and 350 kGy were applied to the UHMWPE samples. The study of physical and chemical qualities has involved a variety of spectroscopy techniques, including Fourier Transform Infrared spectroscopy, X-ray diffraction, mechanical property changes, and biocompatibility properties. New bands are formed, as indicated by FT-IR analysis, and this process is linked to the oxidation of irradiation polymer chains and the production of carbon dioxide. The crystallinity of irradiated samples increases as the gamma radiation increases, according to XRD patterns. The analyzed optical results exhibit improvements in the optical characteristics of the irradiated samples. The absorbance spectra of the irradiated samples showed a shift toward the high of wavelength values in the absorption edge as compared to the pristine sample. On the other hand, the optical absorption edge has an increasing tendency as the dose of gamma-ray radiation is increased. As the gamma-ray dose increases, the absorption edge moves toward the longer wavelength. The measurements of the contact angle indicate that the surface free energy rises with increasing gamma irradiation. It was detailed how the mechanical properties of the irradiated UHMWPE samples were measured. The mechanical measurements indicate that the mechanical properties are dose-dependent to some extent. Furthermore, as gamma doses rise, so does the hardness of irradiated UHMWPE.

Long-Term Afterglow Measurement of Scintillators after Gamma Irradiation

The long-term afterglow of scintillators is an important aspect, especially when the light signal from a scintillator is evaluated in the current mode. Scintillators used for radiation detection exhibit an afterglow, which usually comes from multiple components that have different decay times. A high level of afterglow usually has a negative influence on the detection parameters for the energy resolution in spectrometry measurements or X-ray and neutron imaging. The paper deals with the long-term afterglow of some types of scintillators, which is more significant for integral measurement when the current is measured in a photodetector. The range of decay times studied was in the order of tens of seconds to days. Seven types of scintillators were examined: BGO, CaF2(Eu), CdWO4, CsI(Tl), LiI(Eu), NaI(Tl), and plastic scintillator. The scintillators were excited by gamma-ray radiation. After irradiation, the detection unit, along with the scintillator, was moved to a laboratory where the anode current of the photomultiplier tube was measured using a picoammeter for at least a day. The measurements showed that CdWO4 and plastic scintillators have relatively low long-term afterglow signals in comparison to the other scintillators studied.

Effective rare-earth dielectric addition and gamma ray irradiation for achieving highly efficient PDMS triboelectric nanogenerator

This research aims to develop the flexible triboelectric nanogenerator (TENG) using PDMS polymer as the main tribo-material and composite with dielectric rare earth oxide, lanthanum chromite compound; LaCrO3, to enhance generated charge density, before add-on its higher electrical output with gamma ray irradiation. Upon study the effect of different amounts of the loaded LaCrO3 and various doses of gamma ray, the optimum condition can be obtained. The PDMS/LaCrO3 at 5 wt% can reach open-circuit voltage (VOC) and shot-circuit current (ISC) at 89 V and 448 μA. The impressive results of output further appear by additional irradiated gamma radiation. At 150 kGy dose of Irradiated gamma ray, VOC and ISC can jump to 161 V and 963 μA. These output signals, especially ISC, can be ∼34 times higher than that of the pristine PDMS. Scientific discussion regarding characterization, operating mechanism, dielectric properties and electrical output is provided. The practical application of being a small power source is also developed. Therefore, this research can show another useful application of gamma ray in the field of materials design for energy harvesting devices. The knowledge provided in this research can also serve as potential guidance in the field of specific TENG utilization.

Gamma-ray irradiation-induced effects on Er3+-doped Li2O-Bi2O3-B2O3-TeO2 glass: Structural, optical, luminescence, and radiation shielding properties

In the present study, we report the gamma (γ) ray irradiation-induced structural, optical, luminescence and radiation shielding properties of Er3+-doped Li2O-Bi2O3-B2O3-TeO2 glasses prepared by melt-quenching technique. It was evidence of the slight reductions in density and refractive index while maintaining stable optical properties upon the γ irradiation. Additionally, increased molar volume and polarizability indicated a less compact network. Raman spectroscopy shows broadened peaks and intensity reductions at key vibrational modes. The UV–Vis–NIR absorption spectra reveal the shift in the absorption edge and reduction in the intensities of Er³⁺ absorption bands (around 450, 520, 550, and 650 nm) with higher radiation doses, indicating radiation-induced damage. It was found that the band gap values decreased from 2.58 eV to 1.30 eV for un-irradiated glass to 90 kGy irradiated glass, and Urbach energy was found to increase from 0.18 to 1 eV respectively, indicating structural disorder and localized states within the band gap. PL emission spectra demonstrated intensity changes and peak shifts with γ radiation dose while maintaining a dominant green emission from 4S3/2 → 4I15/2 and 2H11/2 → 4I15/2 transitions, supported by the CIE diagram analysis. The NIR emission spectra also displayed a peak at 1530 nm with decreasing intensity, indicating defect-induced non-radiative recombination centres. Luminescence lifetime decay profiles indicated reduced lifetimes at higher γ doses, suggesting introduced non-radiative decay pathways. Furthermore, Phy-X software analysis highlighted effective γ-ray shielding influenced by chemical composition and photon flux, with MAC sharply decreasing to 1.8 cm2/g at 0.1 MeV and stabilizing, while LAC showed reduced attenuation efficiency at higher energies. HVL and TVL increased with energy, stabilizing around 4–5 cm and 15–16 cm, respectively, necessitating thicker materials for effective shielding at higher photon energies. MFP rapidly increased to 6–7 cm at 2 MeV, stabilizing at higher energies, while Zeff decreased sharply before stabilizing around 1 MeV. The EBF and EABF trends exhibited higher values at low energies, stabilizing at higher energies, indicating effective photon interaction and resonance effects.

Effect of γ-rays irradiation on the structural, magnetic, and electrochemical properties of ZnMn2O4 nanoparticles

The study explored the effect of gamma-ray irradiation on the physical, magnetic, and electrochemical properties of ZnMn2O4 synthesized by the burning method. On the physical characterization side, the study utilized multiple metrology techniques to determine the impact of radiation dosage on bond lengths, density, crystallite size, micro strain, lattice constant, and dislocation density. No irradiation impact on the sample's tetragonal spinel structure was observed up to 250 kGy doses. However, the lattice parameters increased post-γ-irradiation and were apparent in the morphology change of irradiated samples compared to control spinel. Conversely, the magnetic parameters decreased post-irradiation based on the vibrating-sample magnetometry (VSM) testing of control and γ-irradiated samples. Changes in parameters like saturation magnetization (Ms) and magneton number (nB) can be attributed to ion-induced disorder and cation distribution in irradiated samples. Finally, the electrochemical testing showed supercapacitor behavior for all ZnMn2O4 samples, with a positive impact of radiation on electrical capacitance and stability. While the γ-irradiated sample with a 250 kGy dose showed a capacitance (Csp) of 515 F/g with 87.6% stability, the control sample had a Csp of 123 F/g and 78% stability. ZnMn2O4 material meets the needs of energy storage devices operating at high ionizing radiation doses.

Improvement of antibacterial activity of AgNPs@PVA-PVP ternary nanocomposite films followed by gamma-ray irradiation treatment for biomedical applications

Our study investigates the influence of several doses of gamma rays on the antibacterial behavior of nanocomposite of silver nanoparticles (AgNPs) doped in a blend of poly (vinyl alcohol) (PVA)-Polyvinyl Pyrrolidone (PVP). AgNPs@PVA-PVP nanocomposite films have been fabricated by laser ablation method, and then the synthesized films were subjected to various gamma ray’s doses. X-ray diffraction (XRD) data shows a diffraction peak at 2θ = 38° assigned to the existence of AgNPs. Ultraviolet–visible (UV-Vis) results confirm the characteristic peak of silver nanoparticles at 425 nm. The cell viability and antibacterial behavior results confirmed the enhancement in the performance of AgNPs@PVA-PVP composite after irradiated to gamma rays. These values of cell viability have been raised by increasing the dose of gamma rays to 94.5±6.5 % for dose at 70 kGy gamma rays. The values of the inhibition zone of microorganisms were enhanced by raising the doses of gamma rays to 19.5±0.5 and 21.3±0.6 against E. coli and S. aureus respectively specifically for nanocomposite with gamma dose 70 kGy. Thus, the improved antibacterial activity of AgNPs@PVA-PVP nanocomposite could be used in biomedical applications.

Characteristics of purple-green stem Echinacea in the responses of gamma ray irradiation

The increasing demand of Echinacea purpurea as a raw material for herbal medicines and its availability which still relies on imported supplies encourage the development of Echinacea on a national scale. This research aims to increase the diversity of Echinacea to rise varieties of germplasm diversity, in hope later it helps to produce good qualities of Echinacea. Research was conducted from August 2022 to February 2023 at the Jumantono Experimental Laboratory, Faculty of Agriculture, UNS. This study used a simple experimental design method that compared the control treatment with gamma radiation treatment of 20, 30, and 40 Gy. Each treatment was repeated as many as 20 replicates, so there were 80 experimental units. Data were analysed descriptively and by independent t-test. Limited to this study, it was concluded that gamma ray irradiation enhanced characteristic of purple-green stem Echinacea compared to the control treatment.

Propagation mechanism of E’-center and NBOHC in fused silica induced by gamma-ray irradiation

The degradation of optical transmittance induced by the propagation of point defects in fused silica under gamma-ray irradiation severely threatens the service life of optical components. Existing studies have recognized the importance of this issue through the testing of point defect content before and after irradiation. However, the specific evolution process of these point defects remains unclear. In this paper, experiments and deep potential molecular dynamics (DeePMD) simulations were performed to investigate the essence of degradation in optical transmittance and the propagation mechanism of point defects during gamma-ray irradiation. The results indicate that the optical transmittance significantly decreases within the range of 210 nm to 380 nm, and the degree of change increases with an increase in irradiation dose. The propagation of E’-center and nonbridging oxygen hole center (NBOHC) defect pairs is the fundamental cause for the decrease in transmittance. Both experimental and simulation results indicate that E’-centers and non-bridging oxygen hole centers (NBOHC) originate from the evolution of small rings (n=3 and 4). Additionally, DPMD simulations reveal that under the thermal history induced by gamma-ray irradiation, the formation of small rings (n=3 and 4) occurs at the expense of larger rings (n=6 and 7). The research results provide valuable insights into the propagation mechanism of point defects and contribute to designing the service life of optical components.

Rational design and preparation of the modified polyimide copolymer with superior anti-gamma irradiation

To improve polymer-based bonded solid lubricating materials with excellent anti-gamma irradiation performance, a polyimide (BPI, Polyimide containing hexafluoropropane 2,2-bis(3-amino-4-hydroxyphenyl)diamine monomer) copolymer containing phenolic hydroxyl and trifluoromethyl groups was synthesized based on a conventional two-step method. Comparative studies have been conducted to investigate the effects of gamma irradiation on microstructure, thermal stability, mechanical and tribological properties under the different irradiation dose conditions. The results show that, compared with the pure polyimide (PI) and corresponding coatings, the modified BPI copolymer and coatings have better gamma-ray irradiation resistance duo to the copolymer contains lots of the activated phenolic hydroxyl groups and fluorine, which could be effectively inhibit the active destruction of parts of chain structure of copolymer, resulted in the BPI copolymer and BPI based coatings possess good comprehensive mechanical and tribological properties after 1000 kGy gamma irradiation. This study provides a novel approach for the design and preparation of lubricating coatings for nuclear energy systems.

Effect of hybrid lead-PVA fibers on microstructure and radiation shielding properties of high-performance concrete

With the widespread application of nuclear technology in the medical and energy fields, the demand for efficient radiation shielding materials is increasing. Employing only lead or polyvinyl alcohol (PVA) fiber reinforcement cannot achieve improvements in the brittleness of high-performance concrete (HPC) while also enhancing radiation shielding efficiency and mechanical properties. This study develops a novel HPC for radiation attenuation, incorporating magnetite as the aggregate and reinforced with hybrid lead-PVA fibers (RSHPC). The synergistic effects of various proportions of hybrid lead-PVA fibers on the mechanical properties, three-dimensional microstructure, pore structure, and interfacial transition zone (ITZ) were investigated. In addition, the radiation attenuation capacities of RSHPC with different hybrid lead-PVA fiber proportions were evaluated through experimental and simulation analysis. The results show that hybrid lead-PVA fibers notably improve the air-void structure of RSHPC. The incorporation of PVA fibers, by improving the ITZ of matrix, effectively mitigates the negative impact of lead fibers on mechanical performance. The refinement of pore structure and the introduction of light and heavy nuclides lead to a significant enhancement in the gamma-ray and neutron radiation attenuation capabilities of RSHPC. Utilizing X-ray computed tomography (X-CT) for three-dimensional reconstruction further indicates the optimization impact of hybrid lead-PVA fibers on the microstructure, notably in the improvement of pore distribution and fiber dispersion, thus enhancing the overall properties and radiation attenuation performance of RSHPC.

Prediction Models for the Hybrid Effect of Nano Materials on Radiation Shielding Properties of Concrete Exposed to Elevated Temperatures

In modern construction, nanomaterials can be added to concrete to improve its radiation shielding properties. A prediction model for the gamma-ray radiation shielding properties, such as linear attenuation coefficient (LAC) of nanomaterial-based concrete remains necessary. This study aims to develop prediction models for LAC of nano modified concrete (NMC) using nano alumina (NA) and carbon nano tubes (CNTs) subjected to high temperatures. These models are based on linear regression and three machine learning algorithms: M5 Prime (M5P), random forest (RF), and extreme gradient boosting (XGBoost). To build the models, results of 117 concrete cubic specimens (100mm size) was utilized as a dataset with varying amounts of NA and CNTs. Relevant variables including temperature, exposure time, and NA and CNTs dosages were considered. To further validate the predicted results, various statistical metrics and K-fold cross-validation were employed to compare and validate the models' output. The results showed that the XGBoost model outperformed other models, with the highest R2 of 0.9975 and the lowest error of 0.4365%. In addition, the impact of each parameter on LAC of NMC was assessed using Shapley Additive Explanations (SHAP) analysis. Sensitivity and SHAP analyses reveal that CNTs has the highest influence on the radiation shielding properties of NMC. In comparison with the previously developed ANN model, the XGBoost and ANN models showed approximately the same prediction power for predicting LAC of NMC.