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Introduction: Sweetpotato faces breeding challenges due to physiological and genomic issues. Gamma radiation is a novel approach for inducing genetic variation in crops. We analyzed the transcriptomic changes in gamma ray-induced sweetpotato mutants with altered stem development compared with those in the wild-type 'Tongchaeru' cultivar. Methods: RNA sequencing analyses were performed to identify changes in the expression of genes related to stem development. Results: Transcriptomic analysis identified 8,931 upregulated and 6,901 downregulated genes, including the upregulation of the auxin-responsive SMALL AUXIN UP RNA (SAUR) and three PHYTOCHROME INTERACTING FACTOR 4 (PIF4) genes. PIF4 is crucial for regulating the expression of early auxin-responsive SAUR genes and stem growth in Arabidopsis thaliana. In the mutant, several genes related to stem elongation, including PIF4 and those involved in various signaling pathways such as auxin and gibberellin, were upregulated. Discussion: Our results suggest that gamma ray-induced mutations influence auxin-dependent stem development by modulating a complex regulatory network involving the expression of PIF4 and SAUR genes, and other signaling pathways such as gibberellin and ethylene signaling genes. This study enhances our understanding of the regulatory mechanisms underlying stem growth in sweetpotato, providing valuable insights for genomics-assisted breeding efforts.
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One of the most well-liked energizing drinks is now tea, which is primarily used in Malaysia. The natural radioactivity in the associated soils where tea plants are cultivated plays a major role in determining the presence of radionuclides in tea leaves. The present study assesses the transfer of radionuclides from soil-to-tea leaves and then estimates the committed effective doses through tea consumption. Tea leaves and the associated soils were obtained from the largest tea plantation area, which is located in the Cameron Highlands, Malaysia. The marketed tea leaves in powdered form were obtained from the supermarkets in Kuala Lumpur. HPGe gamma-ray spectrometry was used to determine the prevailing concentrations of long-lived radioactive materials in tea leaves. Activity concentrations of 226Ra, 232Th, and 40K in tea soils ranged from 49 to 101.7 Bq kg-1, 74.5-124.1 Bq kg-1 and 79.6-423.2 Bq kg-1, respectively, while the respective values in tea leaves are 14.4-23.8 Bq kg-1, 12.9-29.5 Bq kg-1 and 297-387.5 Bq kg-1. Transfer factors of radionuclides showed typical values (<1.0) except for the 40K. The threshold tea consumption rates suggest that one should not consume more than 67 g of tea leaves per day (around 4 g of tea leaves are needed for making 1 cup of tea, so 17 cups per day) to avoid negative health effects. Committed effective doses due to tea consumption are found to be lower (5.18-6.08 µSv y-1) than the United Nations Scientific Committee on the Effects of Atomic Radiation (2000) reference dose guidance limit of 290 µSv y-1 for foodstuffs; however, it should be noted that the guidance limit is recommended for all foodstuffs collectively. Providing data on natural radioactivity in tea leaves grown in Malaysia, this study may help people manage a healthy lifestyle.
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Perilla (Perilla frutescens (L.) var frutescens) is a traditional oil crop in Asia, recognized for its seeds abundant in α-linolenic acid (18:3), a key omega-3 fatty acid known for its health benefits. Despite the known nutritional value, the reason behind the higher 18:3 content in tetraploid perilla seeds remained unexplored. Gamma irradiation yielded mutants with altered seed fatty acid composition. Among the mutants, DY-46-5 showed a 27% increase in 18:2 due to the 4 bp deletion of PfrFAD3b and NC-65-12 displayed a 16% increase in 18:2 due to the loss of function of PfrFAD3a through a large deletion. Simultaneous knockout of two copies of FATTY ACID DESATURASE 3 (PfrFAD3a and PfrFAD3b) using CRISPR/Cas9 resulted in an increase in 18:2 by up to 75% and a decrease in 18:3 to as low as 0.3% in seeds, emphasizing the pivotal roles of both genes in 18:3 synthesis in tetraploid perilla. Furthermore, diploid Perilla citriodora, the progenitor of cultivated tetraploid perilla, harbors only PfrFAD3b, with fatty acid analysis revealing lower 18:3 levels than tetraploid perilla. In conclusion, the enhanced 18:3 content in cultivated tetraploid perilla seeds can be attributed to the acquisition of two FAD3 copies through hybridization with wild-type diploid perilla.
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Rice straw is considered an agricultural waste harmful to the environment, which is abundant in most parts of the world. From this point, the present study is devoted to preparing new composites of two types of glue based on rice straw as a plentiful, low-cost matrix. Straw glue samples were prepared by mixing 20% wt. of rice straw with 80% wt. of animal glue (RS-An) and polyvinyl acetate (RS-PVAC) at different thicknesses of 1, 2, and 3 cm. The chemical composition of the prepared samples was identified by energy dispersive X-ray analysis and their morphology was examined using a scanning electron microscope. The mechanical test explored that RS-An and RS-PVAC respectively required a stress of 25.2 and 25.5 MPa before reaching the breaking point. γ-ray shielding performance was analyzed and determined at numerous photon energies from 0.059 to 1.408 MeV emitted from five-point γ-rays sources using NaI (Tl). Linear attenuation coefficient was calculated by obtaining the area under the peak of the energy spectrum observed from Genie 2000 software in the presence and absence of the sample. The experimental results of mass attenuation coefficient were compared with theoretical data of XCOM software with relative deviation ranging from 0.10 to 2.99%. Geant4 Monte Carlo simulation code was also employed to validate the experimental results. The relative deviation of XCOM and Geant4 outcomes was 0.09-1.77%, which indicates a good agreement between them. Other radiation shielding parameters such as half value layer (HVL), tenth value layer, and mean free path were calculated in three ways: experimentally, theoretically from the XCOM database, and by simulation using Geant4 code. Additionally, effective atomic number (Zeff), effective atomic number (Neff), equivalent atomic number (Zeq), and buildup factors were evaluated. It was confirmed that the γ-ray shielding properties were further boosted by mixing rice straw with the animal glue compared to the synthetic one.
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Abu Marawat area in the Central Eastern Desert of Egypt is a very promising mineralization district located in the Golden Triangle area. The current study provides an integrated approach from multisource datasets including; remote sensing, airborne geophysical spectrometry and magnetic data supported by field studies and spectroscopic analyses for delineating potential mineralization localities. Several remote sensing techniques were adopted including; Band Ratios, Relative Band Depth, Mineralogical Indices, Spectral Angle Mapper, and Constrained Energy Minimization. These techniques showed that the alteration mineral assemblage is mainly, kaolinite, sericite, and iron oxides, with less abundant chlorite, epidote, and carbonates. In addition, the radiometry data were processed to map the localities with the highest possibility of potassic alteration abundance by integrating the potassium distribution, K/eTh ratio, and the F-parameter maps. The surface and subsurface linear structural features were also mapped using Digital Elevation Model (DEM) and aeromagnetic data, respectively. The surface linear structures were found exhibiting E-W and NE-SW trends, while, the subsurface structures showed dominant NW-SE trend. All the depicted fault trends match well with the local and regional geological and tectonic setting of the study area suggesting structural control on the mineralization in this area. Integration between the results obtained from both the remote sensing and the geophysical data was conducted by a GIS weighted overlay model. The obtained mineralization potentiality map highlights eight potential localities for mineralization. The accuracy of the adopted methodology was demonstrated through fieldwork and spectral analyses; several alteration indicators were observed, including quartz veins, iron oxides, kaolinite, malachite, montmorillonite, chlorite, talc, and sericite alteration indicator minerals. The adopted remote sensing-geophysical approach showed being very effective for mapping the hydrothermal gold-related alteration zones, and is recommended for other similar investigations.
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Developing electro-spun scaffolds with ideal mechanical properties for skin purposes can profit from using the Response Surface Methodology technique to define and optimize the outcome quality and required sterilization for use in vivo. This study investigated the effects of four main independent electrospinning variables for polycaprolactone nanofibers scaffold using multi-variable and multi-objective optimization. It was done to determine significant parameters on responses and find optimal conditions to reach the preferred properties. Young's modulus, elongation-at-break, and tensile strength were the responses. After obtaining appropriate models, the impact share of variables on the responses was determined using Sobol sensitivity analysis. The results showed that flow rate is the most significant parameter of elastic modulus and tensile strength responses, with 76.45 % and 41.27 % impact shares, respectively. The polymer concentration is the following significant parameter on elongation at break, tensile strength and, Young's modulus responses with 64.35 %, 39.485 and, 14.28 % impact share, respectively. Based on the optimized results, a skin scaffold with desired mechanical properties was achieved (under solution concentration of 10 % w/v, flow rate of 2 mL/h, nuzzle-collector distance of 15 cm, and applied voltage of 20 kV). Then it was sterilized with gamma radiation of various doses (25, 40, and 55 kGy) to use in vivo. The SEM analysis indicated no significant change in fibrous morphology due to gamma irradiation at any dosage. FTIR analysis demonstrated the breakup of ester bonds due to gamma irradiation. For samples irradiated by 25 kGy, the crystallinity percentage decreased and chains crosslinking without losing the mechanical stability was dominant. The studies demonstrated that 25 kGy of gamma irradiation could improve the mechanical properties of the optimized PCL skin scaffold, which is very promising for wound healing.
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Identifying the constituting materials of concealed objects is crucial in a wide range of sectors, such as medical imaging, geophysics, nonproliferation, national security investigations, and so on. Existing methods face limitations, particularly when multiple materials are involved or when there are challenges posed by scattered radiation and large areal mass. Here we introduce a novel brute-force statistical approach for material identification using high spectral resolution detectors, such as HPGe. The method relies upon updated semianalytic formulae for computing uncollided flux from source of gamma radiation, shielded by a sequence of nested spherical or cylindrical materials. These semianalytical formulae make possible rapid flux estimation for material characterization via combinatorial search through all possible combinations of materials, using a high-resolution HPGe counting detector. An important prerequisite for the method is that the geometry of the objects is known (for example, from X-ray radiography). We demonstrate the viability of this material characterization technique in several use cases with both simulated and experimental data in spherical geometry.
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Silicon photomultipliers (SiPMs) are solid-state single-photon-sensitive detectors that show excellent performance in a wide range of applications. In FBK (Trento, Italy), we developed a position-sensitive SiPM technology, called "linearly graded" (LG-SiPM), which is based on an avalanche-current weighted-partitioning approach. It shows position reconstruction resolution below 250 µm on an 8 × 8 mm2 device area with four readout channels and minimal distortions. A recent development in terms of LG-SIPM is a larger chip version (10 × 10 mm2) based on FBK NUV-HD technology (near-ultraviolet sensitive), with a peak photon detection efficiency at 420 nm. Such a large-area detector with position sensitivity is very interesting in applications like MR-compatible PET, high-energy physics experiments, and readout of time-projection chambers, gamma and beta cameras, or scintillating fibers, with a reduced number of channels. These SiPMs were characterized in terms of noise, photon detection efficiency, and position resolution. We also developed tiles of 2 × 2 and 3 × 3 LG-SiPMs, reaching very large sensitive areas of 20 × 20 mm2 and 30 × 30 mm2. We implemented a "smart-channel" configuration, which allowed us to have just six output channels for the 2 × 2 elements and eight channels for the 3 × 3 element tiles, preserving a position resolution below 0.5 mm. These kinds of detectors provide a great advantage in compact and low-power applications by maintaining position sensitivity over large areas with a small number of channels.
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Since the beginning of research into radiation and protection against it, the importance of searching for proper materials against radiation hazards has been recognized. Gamma radiation protection materials usually deal with heavy elements with high prices, which are hard to maintain. Polyurethane-based (PU) materials are popular in sound and thermal insulation due to, their low-weight properties and, most importantly, fast and convenient construction ingredients. PU foams (PUF) can be used as radiation shield and noise and heat resistance due to their approachability, light-weight, high resistance, and comfortable construction. This study involved simulation and an experiment to construct and investigate the properties of Polyurethane material doped with lead oxide as a gamma shield. The shield was considered in several weight fractions of lead, yielding several samples. The MCNPX 2.6 Monte Carlo code has been utilized for simulation procedure, and 137Cs was employed as the gamma source in both simulation and experiment. The results offer a promising response against the gamma radiation and are suitable for attenuating gamma rays.
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The increased risk of liver malignancies was found in workers of the first Russian nuclear production facility, Mayak Production Association, who had been chronically exposed to gamma rays externally and to alpha particles internally due to plutonium inhalation. In the present study, we updated the radiogenic risk estimates of the hepatobiliary malignancies using the extended follow-up period (1948-2018) of the Mayak worker cohort and the improved «Mayak worker dosimetry system-2013¼. The cohort comprised 22,377 workers hired at the Mayak PA between 1948 and 1982. The analysis considered 62 liver malignancies (32 hepatocellular carcinomas, 13 intrahepatic cholangiocarcinomas, 16 angiosarcomas, and 1 anaplastic cancer) and 33 gallbladder adenocarcinomas. The analysis proved the positive significant association of the liver malignancy risk (the total of histological types, hepatocellular carcinoma) with the liver absorbed alpha dose from internal exposure. The excess relative risk per Gy (95% confidence interval) of alpha dose (the linear model) was 7.56 (3.44; 17.63) for the total of histological types and 3.85 (0.95; 13.30) for hepatocellular carcinoma. Indications of non-linearity were observed in the dose-response for internal exposure to alpha radiation. No impact of external gamma-ray exposure on the liver malignancy incidence was found. In the study cohort, the number of angiosarcomas among various types of liver malignancies was very high (25.8%), and most of these tumors (73.3%) were registered in individuals internally exposed to alpha radiation at doses ranging between 6.0 and 21.0 Gy. No association with chronic occupational radiation exposure was observed for the incidence of gallbladder malignancies.
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Neoplasias Hepáticas , Neoplasias Induzidas por Radiação , Exposição Ocupacional , Humanos , Exposição Ocupacional/efeitos adversos , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/etiologia , Masculino , Neoplasias Induzidas por Radiação/epidemiologia , Neoplasias Induzidas por Radiação/etiologia , Incidência , Pessoa de Meia-Idade , Feminino , Radiação Ionizante , Estudos de Coortes , Adulto , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etiologia , Federação Russa/epidemiologia , Idoso , Partículas alfa/efeitos adversos , Raios gama/efeitos adversos , Exposição à Radiação/efeitos adversosRESUMO
At the Fukushima Daiichi Nuclear Power Station, radiation sources released in the accident were deposited on various equipment and building structures. During decommissioning, it is crucial to understand the distribution of radiation sources and ambient dose equivalent rates to reduce worker exposure and implement detailed work planning. In this study, the author introduces a method for visualizing radiation sources, estimates their radioactivity using a Compton camera, and derives the dose rate around the radiation sources. In the demonstration test, the Compton camera was used to visualize radioactive hotspots caused by 137Cs radiation sources deposited in the outdoor environment and estimated the radioactivity. Furthermore, the dose rate around the hotspots was calculated from the estimated radioactivity, which confirmed that the calculated dose rate correlated with the dose rate measured using a survey meter. This approach is novel, where a series of analyses were conducted using the Compton camera to visualize radioactive hotspots, estimate the radioactivity, and derive the dose rate in the surrounding environment.
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Methylammonium lead tribromide (MAPbBr3) stands out as the most easily grown wide-band-gap metal halide perovskite. It is a promising semiconductor for room-temperature gamma-ray (γ-ray) spectroscopic detectors, but no operational devices are realized. This can be largely attributed to a lack of understanding of point defects and their influence on detector performance. Here, through a combination of crystal growth design and defect characterization, including positron annihilation and impedance spectroscopy, the presence of specific point defects are identified and correlated to detector performance. Methylammonium (MA) vacancies, MA interstitials, and Pb vacancies are identified as the dominant charge-trapping defects in MAPbBr3 crystals, while Br vacancies caused doping. The addition of excess MABr reduces the MA and Br defects and so enables the detection of energy-resolved γ-ray spectra using a MAPbBr3 single-crystal device. Interestingly, the addition of formamidinium (FA) cations, which converted to methylformamidinium (MFA) cations by reaction with MA+ during crystal growth further reduced MA defects. This enabled an energy resolution of 3.9% for the 662 keV 137Cs line using a low bias of 100 V. The work provides direction toward enabling further improvements in wide-bandgap perovskite-based device performance by reducing detrimental defects.
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Soil is one the most extracted natural raw materials. The vast expanses of fertile alluvial soils of the Indo Gangetic Plains have long remained as abundant soil resource pool for brick manufacturing and construction sectors. Unmonitored continuous removal of soil is reported to cause depletion of soil reserves, loss of soil fertility and affect crop yield. Excavation and removal of soil from isolated patches of land creates low lying and elevated degraded areas which disrupts normal crop cultivation pattern. Natural gamma-ray spectrometry (NGS) can be used as a non-destructive and rapid geophysical sensing method, for identification and delineation of areas with suitable soils. During this work brick kiln areas were visited to understand soil's availability and extraction pattern. NGS measurements of samples from soil profiles were carried out to find if gamma-ray intensities varied with soil clay content. Soil texture and plasticity of the same samples were obtained following standard testing procedures. Winkler and Plasticity charts were used to assess suitability of the soils. A strong linear relationship between gamma-ray potassium (K) intensity and clay contents of soil profile samples (R2 = 0.88) was observed. NGS based devices can be used to scan soil samples rapidly and log shallow depth boreholes in grid sampling design. The gathered spectral gamma-ray data can be then used to predict and generate high resolution 3D models of soil properties, based on which resource areas of suitable soils can be delineated for long term soil extraction without affecting cultivated areas. This will help in delineating areas restricted for soil extraction, which will not only make soil mining sustainable but also address soil conservation by setting aside large cultivated fertile soil areas untouched. Adopting NGS methods will prevent unsystematic removal of fertile soil and creation of degraded lands. This will ultimately result in efficient soil resource management.
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Terbium-157 was radiochemically extracted from an irradiated tantalum target. Since the resulting material contained a significant impurity of 158Tb, 157Tb was isotopically purified using laser resonance ionization at the RISIKO mass separator in Mainz and then implanted on an aluminum (Al) foil. The implanted 157Tb was measured by two different calibrated gamma-ray spectrometers to determine photon emission rates. After dissolving the Al foil, a high purity 157Tb solution was obtained. The corresponding activity concentration was determined with a low relative uncertainty of 0.52% through a combination of liquid scintillation counting using the TDCR method and 4π(X,e)(LS)-(X,γ)(CeBr3) coincidence counting. By combining the results from all measurement techniques, emission intensities for K X-rays and gamma-rays were derived and found to be 16.05(31)% and 0.0064(2)%, respectively. The probability for K electron capture of the first forbidden non-unique transition to the ground state was determined to be 17.16(35)%. The probabilities for the electron-capture branch to the excited level and the ground state were found to be 0.084(4)% and 99.916(4)%, respectively. A Q+ value of 60.23(18) keV was estimated based on simplified BetaShape calculations, assuming an allowed transition.
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This study evaluates the radiological risk associated with the consumption of infant powdered milk in Albania. Infant powdered milk is the basic foodstuff for their growth and development in many countries around the world. The activity concentration of radionuclides (40K, 226Ra, 232Th and 137Cs) was measured in fourteen types by using the gamma-ray technique. The results indicated that the activity concentration of 40K, 226Ra and 232Th were detected in all selected samples, whereas 137Cs were not detected in most of them. The activity concentration of 40K, 226Ra and 232Th varies from 92.83 ± 4.32 to 400.53 ± 17.00 Bq kg-1, 0.80 ± 0.15 to 4.91 ± 0.28 Bq kg-1 and 0.19 ± 0.02 to 1.89 ± 0.14 Bq kg-1, respectively. The highest value for 137Cs was found to be 0.36 ± 0.03 Bq kg-1. The average values of Annual Effective Dose (AED) due to consumption of powdered milk were found to be 664.54 ± 31.11 µSv y-1 for infants ≤1 year and 138.53 ± 5.40 µSv y-1 for infants 1-2 years. The values of dose in this study were lower than the recommended limit of 1 mSv y-1 set by WHO/FAO and ICRP for all ages. Therefore, brands of powdered milk are safe, so, these can be normally consumed by infants in Albania.
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Radioisótopos de Césio , Contaminação Radioativa de Alimentos , Fórmulas Infantis , Radioisótopos de Potássio , Doses de Radiação , Albânia , Humanos , Radioisótopos de Césio/análise , Lactente , Contaminação Radioativa de Alimentos/análise , Fórmulas Infantis/química , Fórmulas Infantis/análise , Radioisótopos de Potássio/análise , Tório/análise , Rádio (Elemento)/análise , Leite/química , Animais , Monitoramento de Radiação/métodosRESUMO
To advance high-energy atmospheric physics, studying atmospheric electric fields (AEF) and cosmic ray fluxes as an interconnected system is crucial. At Mt. Argats, simultaneous measurements of particle fluxes, electric fields, weather conditions, and lightning locations have significantly enhanced the validation of models that describe the charge structures of thunderclouds and the mechanics of internal electron accelerators. In 2023, observations of the five largest thunderstorm ground enhancements (TGEs) revealed electric fields exceeding 2.0 kV/cm at elevations just tens of meters above ground-potentially hazardous to rockets and aircraft during launch and charging operations. Utilizing simple yet effective monitoring equipment developed at Aragats, we can mitigate the risks posed by these high-intensity fields. The Mendeley dataset, comprising various measured parameters during thunderstorm activities, enables researchers to perform advanced correlation analysis and uncover complex relationships between these atmospheric phenomena. This study underscores the critical importance of integrated atmospheric studies for ensuring the safety of high-altitude operations and advancing atmospheric science.
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166Ho (T1/2≈ 26.8 h) is an emerging theragnostic radionuclide of interest in nuclear medicine due to its peculiar decay scheme, featuring high-energy ß- emission (≈ 1.8 MeV) coupled with the main gamma-ray emission (≈ 80.6 keV). Using the new 166Ho activity standard and the well-calibrated, high-energy resolution HPGe detector, both available at ENEA-INMRI, a new determination of several 166Ho gamma-ray emission intensities, Iγ, was performed with low uncertainty. The new Iγ values contributed to the Decay Data Evaluation Project.
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Ionizing radiation is valuable for healthcare, industry, and agriculture. However, excessive exposure to ionizing radiation is detrimental to humans and the environment. Radiation protection aims at protecting people and the environment from the harmful effects of ionizing radiation. This work aimed to study the effectiveness of composites of red clay and waste glass for ionizing radiation shielding. Five samples of different mix ratios of red clay to waste glass were fabricated into different dimensions using hand molding, dried, and burnt. The samples were characterized for ionizing radiation shielding. Monte-Carlo simulation was done using the GEANT4 toolkit and web-based NIST-XCOM photon attenuation database. The findings show that the measured half value layer (HVL) for the composite bricks showed a linear decrease from (6.13± 0.10) cm for the CNT sample that had 0 % waste glass to (4.62± 0.12) cm for the RCG11 sample that had 50 % waste glass. The GEANT4 simulated HVL values for CNT and RCG11 samples were (6.05±0.01) cm and (4.79±0.01) cm respectively. The NIST-XCOM values were (6.09±0.09) cm and (4.81± 0.01) cm for CNT and RCG11 respectively. The measured and simulated results were in good agreement. The findings of this study indicate an improvement in the shielding properties of red clay with the addition of waste glass and will promote radiation safety by providing an environmentally friendly alternative shielding material.â¢Proper shielding is key in promoting radiation safety and protection. There is a need for alternative shielding materials that can be used for walling during the construction of structures that house radioactive materials.â¢Red clay and waste glass composite bricks can provide alternative ionizing radiation shielding material.â¢This study will promote environmentally friendly practices in radiation safety and protection.
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Electrons in circular motion emit electromagnetic radiation and lose their energy and angular momentum, both of which are carried away by the radiation field. Electromagnetic radiation from such electrons is not only circularly polarized but also, in general, possessing helical phase structure, the former of which corresponds to spin angular momentum and the latter orbital angular momentum. Based on the classical electrodynamics, we show that the chiral topological property related to the orbital angular momentum arises from deformation of the electromagnetic field due to the relativistic effect.
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Non-destructive methodology for determining carbon content in large or semi-infinite (soil) samples is discussed. This methodology is based on deconvoluting the sample's gamma spectra (received by tagged neutron method) on the sample component's spectra by accounting for neutron and gamma radiation attenuations. This algorithm was tested with both Monte-Carlo simulations and experimental gamma spectra. Good agreement was found between defined and actual sample component content. Application of this method for soil carbon determinations in agricultural fields is discussed.