Effect Of Rays Research Articles

Effect of gamma ray and gamma ray + EMS combination treatment on M1 and M2 generations of white seeded sesame (Sesamum indicum)

Sesame is an important oil seed crop containing high amount of edible oil along with nutritional quality. A wide range of colours is observed in the sesame seeds ranging from white to black. White seeded sesame has huge demand in confectionary market besides the oil market. However, yield level of sesame is low compared to other oilseed crops. Improvement of sesame in terms of yield and quality is only possible by utilization of genetic variations. The present investigation was conducted at Experimental Farm, Agricultural College and Research Institute, Madurai during 2018 and 2019 to create novel genetic variations using gamma ray and combination of gamma ray + EMS as mutagens. The white seeded sesame variety VRI 3 was treated with gamma ray viz., 300 Gy, 350 Gy, 400 Gy and gamma ray + EMS combination treatments viz., 300 Gy + 10 mM, 350 Gy + 10 mM and 400 Gy + 10 mM. In the first generation, the mean performance for morphological and physiological traits decreased with increase in dose of mutagens; while biochemical traits increased at lower doses and reduced at higher doses. High effectiveness for chlorophyll mutants was recorded in 400 Gy gamma ray treatment. Gamma ray treatments were found to induce higher number of macro mutants than combination treatments. From this study it is concluded that biochemical traits get enhanced in lower doses of gamma ray treatment and gamma ray treatment is more suitable for induction of viable mutants than combination treatments.

Computation of the uncollided-flux moments with advanced MOC and QP methods

The growing need to solve radiation protection and shielding problems in reasonable computational times has led to an increasing interest in the use of deterministic approaches. Codes of this type commonly use the discrete-ordinates method. In cases of propagation of point sources in low scattering media, which are typical of shielding studies, the approximation leads to a set of numerical artefacts known as ray effect. One of the most commonly used techniques to mitigate this effect is the calculation of the uncollided flux, which is the most affected flux component, with a fine transport operator. In this paper we propose four different approaches: the method of characteristics (MOC), the trajectory-splitting MOC (TS-MOC), the Monte Carlo MOC (MC-MOC) and the method based on quadrature points (QP). They have been implemented inside the Cartesian solver IDT. This paper contains the formal description of the four numerical methods and their verification over a set of benchmark problems. An analysis of the accuracy and the computation performances of the methods is also given. Finally, a comparison of the four methods on the Kobayashi benchmark problem is proposed.

Biological Effect of Gamma Rays According to Exposure Time on Germination and Plant Growth in Wheat

Gamma rays as a type of ionizing radiation constitute a physical mutagen that induces mutations and could be effectively used in plant breeding. To compare the effects of gamma and ionizing irradiation according to exposure time in common wheat (Keumgang, IT 213100), seeds were exposed to 60Co gamma rays at different dose rates. To evaluate the amount of free radical content, we used electron spin resonance spectroscopy. Significantly more free radicals were generated in the case of long-term compared with short-term gamma-ray exposure at the same dose of radiation. Under short-term exposure, shoot and root lengths were slightly reduced compared with those of the controls, whereas long-term exposure caused severe growth inhibition. The expression of antioxidant-related and DNA-repair-related genes was significantly decreased under long-term gamma-ray exposure. Long-term exposure caused higher radiosensitivity than short-term exposure. The results of this study could help plant breeders select an effective mutagenic induction dose rate in wheat.

Effect of gamma rays and accelerated electron beam on medullary lipids decomposition: influence of dose and irradiation temperature.

Ionizing radiation sterilization of non-defatted bone grafts has been found to deteriorate their quality and biocompatibility due to induction of lipid peroxidation products toxic for osteoblast-like cells. Therefore, the purpose of our study was to evaluate the effect of two types of ionizing radiation-gamma rays (G) or accelerated electron beam (EB) applied with two doses at different temperature conditions on hydrocarbons production, resulting from decomposition of palmitic and oleic acids-most abundant fatty acids in medullary lipids. Bone marrow samples isolated from femoral shafts of 6 male donors (aged 46-67 years) were irradiated with G or EB with doses of 25 or 35kGy at different temperature conditions (ambient or deep freezing temperature). Fresh-frozen, non-irradiated samples served as control. Marrow lipids were extracted with n-hexane (Soxhlet's method), hydrocarbons fraction isolated on Florisil column chromatography, separated by gas chromatography and detected by mass spectrometry. Irradiation of bone marrow with sterilization doses of ionizing radiation (G and EB) was found to induce lipid radiolysis as measured by resulting hydrocarbons production. The effect was dose-dependent, whereas no marked influence of radiation type was observed. In contrast, irradiation temperature had a profound effect on lipids decomposition which was partially prevented while irradiation was performed in deep frozen state. Defatting of bone grafts prior to ionizing radiation sterilization seems essential for their biocompatibility, whereas irradiation in a deep-frozen state might compromise the effectiveness of sterilization and needs further studies.

Effect of Ultraviolet Radiation on various Bacterial Species

The study of microorganism is called microbiology, which includes bacteria, viruses, fungi and Protozoa. Microbes play a major role in this field. Microbes are also used for life-saving drugs etc. The effect of ultraviolet rays on the bacteria’s are mostly lethal to them, UV is a minor fraction of the solar spectrum reaching the ground surfaces, the UV light radiation will reduce the microbes in the surroundings as well as in the labs. The aim of this study was to evaluate the effect of the ultraviolet rays on pathogenic bacteria’s. Three organisms were selected for the study. Staphylococcus aureus and Streptococcus faecalis. 30 watts UV tube was used to evaluate the antibacterial activity of the UV radiation. The exposure time was determined as 5, 10 and 15 mins at a close distance of 10cm. 20 microliter of suspension was taken and mixed in 2 ml of sterile normal saline and exposed for respective duration. Sub culture was done on suitable media after the exposure. Time exposed plates were incubated at 37 degree Celsius overnight and checked for the total CFU and data were tabulated. The Ultra violet radiation of pathogenic bacteria resulted in a significant total colony forming unit. Ultraviolet rays were lethal to the bacteria’s. There are many airborne bacteria’s surrounded by environment ultraviolet rays exposure will cause an apparent decrease in the pathogenic bacteria’s.

Effect of Ultraviolet Radiation on Various Bacterial Species

The study of microorganism is called microbiology, which includes bacteria, viruses, fungi and Protozoa. Microbes play a major role in this field. Microbes are also used for life-saving drugs etc. The effect of ultraviolet rays on the bacteria’s are mostly lethal to them, UV is a minor fraction of the solar spectrum reaching the ground surfaces, the UV light radiation will reduce the microbes in the surroundings as well as in the labs. The aim of this study was to evaluate the effect of the ultraviolet rays on pathogenic bacteria’s. Three organisms were selected for the study. Staphylococcus aureus and Streptococcus faecalis. 30 watts UV tube was used to evaluate the antibacterial activity of the UV radiation. The exposure time was determined as 5, 10 and 15 mins at a close distance of 10cm. 20 microliter of suspension was taken and mixed in 2 ml of sterile normal saline and exposed for respective duration. Sub culture was done on suitable media after the exposure. Time exposed plates were incubated at 37 degree Celsius overnight and checked for the total CFU and data were tabulated. The Ultra violet radiation of pathogenic bacteria resulted in a significant total colony forming unit. Ultraviolet rays were lethal to the bacteria’s. There are many airborne bacteria’s surrounded by environment ultraviolet rays exposure will cause an apparent decrease in the pathogenic bacteria’s.

Diffuse GeV emission in the field of HESS J1912+101 revisited

We have analyzed 12 years of Fermi Large Area Telescope data toward the HESS J1912+101 region. With the latest source catalog and diffuse background models, a γ-ray excess is detected with a significance of ~8σ in the energy range of above 10 GeV. It has been argued that the diffuse GeV emission in the vicinity of HESS J1912+101 are from an extended pulsar wind nebula powered by PSR J1913+1011 and also that the hard GeV emission above 10 GeV stems from the shell-type supernova remnant and is connected with the TeV emissions. Different from previous works, our analysis indicates that the H2 spatial template is preferred over the other spatial templates, suggesting that the diffuse emission component spatially correlates with the dense molecular gas. This spatial correlation favors a hadronic emission scenario, although a leptonic origin cannot be ruled out. In the hadronic scenario, the parent proton spectrum can be described by a power-law function with an index of α = 2.36 ± 0.16. Above 50 GeV, there is no emission, and the upper limits reveal a spectral cutoff or break in the parent proton spectrum that can be explained as propagation effects of cosmic rays. We argue that the parent protons may come from the candidate supernova remnant HESS J1912+101 or the young massive star cluster Mc20.

What’s next in the use of opacifiers for cosmetic coatings of solid dosage forms? Insights on current titanium dioxide alternatives

The consolidated use of coatings containing E171 (i.e. titanium dioxide, TiO2) as an opacifier has made the white color of the resulting dosage forms a quality standard in the pharmaceutical and dietary supplement fields. This color is also associated with the efficiency of the coating layer in protecting the substrate from the effects of UV rays. However, health risks related to diet exposure to TiO2 has recently been advanced and its addition in coating formulations has been seriously questioned. As a consequence, in principle safer TiO2-free formulations have been recently launched on the market, especially for coatings of dietary supplements. In this work, we evaluated the overall physico-technological characteristics and performance of immediate release tablets coated with a variety of commercial cosmetic formulations free of E171. Moreover, a quantitative method based on the CIELab color space was proposed for the first time for studying the covering/coloring performance of the coating formulations. Based on the results obtained, the possibility to achieve a satisfactory covering capability and a degree of white comparable to that of a standard TiO2-containing reference with all the commercially-available ready-to-use TiO2-free products considered, without affecting the dissolution performance, was demonstrated.

The Effect of Gamma Rays on Some Electrical Properties of Polyethylene Glycol (PEG) Dissolved in Distill Water

AbstractIn this paper, some electrical properties of (polyethylene glycol [PEG]) which is dissolved in distal water after and before irradiation by (γ‐ray) (60Co) with dose of (8000 rad) and average radiation (320 rad min−1) for (25 min) have been studied. The study of electrical properties has included two lines; first the measurement of capacity, electrical conductivity of (PEG), and second the calculation of dielectric constant and molar conductivity. It has been founded that the capacitance, electrical dielectric constants, and conductivity are increased after irradiation and increased with increasing of concentration and also after irradiation but the molar conductivity is decreased with increasing of the concentration. The temperature is constant approximate to room temperature (25°C) in all calculated measurements. The cross linking of polymer chains is the main cause of the change in values of properties that may be resulted and then increased in the average viscosity molecular weight for material (PEG) used in research.

Feasibility study of β-ray detection system for small leakage from reactor coolant system

Because existing reactant coolant system (RCS) leakage detection mechanisms are insensitive to small leaks, a real-time, direct detection system with a detection threshold below 0.5 gpm∙hr−1 was studied. A beta-ray detection system using a silicon detector with good energy resolution for beta rays and a low gamma-ray response was proposed. The detection performance in the leakage condition was evaluated through experiments and simulations. The concentration of 16N in the coolant corresponding to a coolant leakage of 0.5 gpm was calculated using the analytic method and ORIGEN-ARP. Based on the concentration of 16N and the measurement of the silicon detector with 90Sr/90Y, the beta-ray count rate was estimated using MCNPX. To evaluate the effect of gamma rays inside the containment building, the signal-to-noise ratio (SNR) was calculated. To evaluate the count rate ratio, the radiation field inside the containment building was simulated using MCNPX, and response evaluation experiments were performed using beta and gamma rays on the silicon detector. The expected beta-ray count rate at 0.5 gpm leakage was 7.26 × 105 counts/sec, and the signal-to-background count rate ratio exceeded 88 for a transport time of 10 s, demonstrating its suitability for operation inside a reactor containment building.

Gamma ray effects on the properties of PbI2 thin films

This study reports the impact of γ-ray exposure on the nanostructural, morphological, and optical characteristics of lead iodide (PbI2) thin films (TFs). These PbI2 were deposited on glass substrates using a spin coating technique. The γ-ray irradiation was carried out using Co-60 gamma source with dose range from 0 to 100 kGy. The X-ray diffraction (XRD) results revealed a decrease in crystallinity and an increase in crystallite size of PbI2 as a function of γ-ray dose. Field emission scanning electron microscopy (FESEM) exhibited the variations in surface morphology with increasing γ-ray dose. The elemental composition of as prepared TFs was confirmed by energy dispersive X-rays (EDX) analysis. The optical transmission of PbI2 TFs was evaluated with varying the γ-ray doses. The estimated energy band gap (Eg) reduced from 2.54 to 2.45 eV with γ-ray dose. Photoluminescence (PL) spectra represent a broad peak centered at 507.64 nm with a hump present at 519.73 nm in the as prepared sample, which grow gradually with increasing the γ-ray dose. The maximum value of mobility was found to be 10.48 cm2 V−1 s−1 at 50 kGy. The change in the mobility is associated with the density of structural defects influenced by γ-ray doses. These effects conclude that γ-irradiation played a key role in structural, electrical and optical properties of the PbI2 TFs and proposes that the γ-irradiation response makes it a good candidate for radiation detecting material application.

Numerical results for radiative heat transfer in finite cylindrical medium with isotropic scattering

In recent years, the interest in radiative heat transfer in cylindrical media has increased primarily because of its several applications related to combustion chambers, furnaces, and high temperature heat exchangers. Although there are many papers dealing with the radiative transfer in such geometry, there is lack of high precision benchmarks. Such scarcity is related to the fact that some researches present inaccurate results and most published works are limited to presenting results only in graphics. The shortage is more evident in the case of multidimensional problems, like those in which incident radiation and radiative heat fluxes vary in the axial direction. These problems can be approached in many ways; in the integral formulation, the angular variables are completely eliminated by integration over the solid angle, which allows the elimination of the ray effect and the consequent obtainment of more accurate numerical results. A strategy that can be used simultaneously with the integral formulation is the use of the singularity-subtraction technique with the Nyström method, which provides high quality numerical results with relatively low computational times if combined with mathematical refinements. Following this methodology, in the present research, radiative heat transfer problems in finite cylindrical media with isotropic scattering are solved. High precision numerical results for incident radiation and radiative heat fluxes in the radial and axial directions are provided and validated by comparing with results available in the literature.

Ray effects mitigation using the Monte Carlo first collision source method and application to the Kobayashi benchmark problems

The problem of ray effects, arising in the calculation of local source problems with low scattering media, have been perplexing the discrete ordinates (SN) method. Conventionally, the first collision source technique based on deterministic methods is used to remedy ray effects. In this paper, we investigate a technique based on Monte Carlo method to calculate first collision source distributions and consequently mitigate the ray effects. The Monte Carlo first collision source (MC-FCS) method has been implemented into the three-dimensional (3D) parallel SN transport code Marvin. The 3D Kobayashi benchmark problems were used to systematically verify effectiveness of the MC-FCS solver and to evaluate its computational efficiency. Numerical results show that: the MC-FCS solver has been correctly implemented; the MC-FCS method is highly effective in remedying ray effects; and computational efficiency of MC-FCS is acceptable, especially considering the great improvement in solution accuracy it can bring.

Cosmic rays from massive star clusters: a close look at Westerlund 1

ABSTRACT We study the effect of cosmic ray (CR) acceleration in the massive compact star cluster Westerlund 1 in light of its recent detection in γ-rays. Recent observations reveal a 1/r radial distribution of the CR energy density. Here, we theoretically investigate whether or not this profile can help to distinguish between (1) continuous CR acceleration in the star cluster stellar wind-driven shocks and (2) discrete CR acceleration in multiple supernovae (SNe) shocks – which are often debated in the literature. Using idealized two-fluid simulations and exploring different acceleration sites and diffusion coefficients, we obtain the CR energy density profile and luminosity to find the best match for the γ-ray observations. We find that the inferred CR energy density profiles from observations of γ-ray luminosity and mass can be much different from the true radial profile. CR acceleration at either the cluster core region or the wind termination shock can explain the observations, if the diffusion coefficient is κcr ∼ 1027 cm2 s−1 and a fraction of ${\approx}10-20{{\ \rm per\ cent}}$ of the shock power/post-shock pressure is deposited into the CR component. We also study the possibility of discrete SNe explosions being responsible for CR acceleration and find that with an injection rate of 1 SN in every ∼0.03 Myr, one can explain the observed γ-ray profile. This multiple SN scenario is consistent with X-ray observations only if the thermal conductivity is close to the Spitzer value.

Frequency and Spectrum of Mutations Induced by Gamma Rays Revealed by Phenotype Screening and Whole-Genome Re-Sequencing in Arabidopsis thaliana.

Genetic variations are an important source of germplasm diversity, as it provides an allele resource that contributes to the development of new traits for plant breeding. Gamma rays have been widely used as a physical agent for mutation creation in plants, and their mutagenic effect has attracted extensive attention. However, few studies are available on the comprehensive mutation profile at both the large-scale phenotype mutation screening and whole-genome mutation scanning. In this study, biological effects on M1 generation, large-scale phenotype screening in M2 generation, as well as whole-genome re-sequencing of seven M3 phenotype-visible lines were carried out to comprehensively evaluate the mutagenic effects of gamma rays on Arabidopsis thaliana. A total of 417 plants with visible mutated phenotypes were isolated from 20,502 M2 plants, and the phenotypic mutation frequency of gamma rays was 2.03% in Arabidopsis thaliana. On average, there were 21.57 single-base substitutions (SBSs) and 11.57 small insertions and deletions (InDels) in each line. Single-base InDels accounts for 66.7% of the small InDels. The genomic mutation frequency was 2.78 × 10−10/bp/Gy. The ratio of transition/transversion was 1.60, and 64.28% of the C > T events exhibited the pyrimidine dinucleotide sequence; 69.14% of the small InDels were located in the sequence with 1 to 4 bp terminal microhomology that was used for DNA end rejoining, while SBSs were less dependent on terminal microhomology. Nine genes, on average, were predicted to suffer from functional alteration in each re-sequenced line. This indicated that a suitable mutation gene density was an advantage of gamma rays when trying to improve elite materials for one certain or a few traits. These results will aid the full understanding of the mutagenic effects and mechanisms of gamma rays and provide a basis for suitable mutagen selection and parameter design, which can further facilitate the development of more controlled mutagenesis methods for plant mutation breeding.

Non-Thermal Biological Effect of Graphene Far-Infrared Ray on <i>Saccharomyces cerevisiae</i> Cells

Graphene materials can emit far-infrared ray, but the biological effects of graphene far-infrared ray have not been studied. Furthermore, the non-thermal biological effect of far-infrared ray on organism has not been systematically studied independently of the thermal effect. The purpose of this study was to investigate the non-thermal biological effect of graphene far-infrared ray (gFIR) on Saccharomyces cerevisiae cells. In this work, stringent control of the cultivation conditions was carried out to ensure the stability and constancy of the culture and its temperature. Flow cytometry was used to detect the non-thermal effect of gFIR irradiation on cell membrane permeability, mitochondrial membrane potential (MMP) and intracellular reactive oxygen species (ROS) content. Compared with the control group, cell membrane permeability of the gFIR exposure cells decreased by 4.7%, MMP increased by 16% and intracellular ROS reduced by 10.7%. The results revealed the valuable features of the non-thermal biological effect of gFIR on Saccharomyces cerevisiae cells, and the further analysis demonstrated that graphene far-infrared materials should have great application value in disease prevention and health promotion.

Cryopreserved Stem Cells Incur Damages Due To Terrestrial Cosmic Rays Impairing Their Integrity Upon Long-Term Storage

Stem cells have the capacity to ensure the renewal of tissues and organs. They could be used in the future for a wide range of therapeutic purposes and are preserved at liquid nitrogen temperature to prevent any chemical or biological activity up to several decades before their use. We show that the cryogenized cells accumulate damages coming from natural radiations, potentially inducing DNA double-strand breaks (DSBs). Such DNA damage in stem cells could lead to either mortality of the cells upon thawing or a mutation diminishing the therapeutic potential of the treatment. Many studies show how stem cells react to different levels of radiation; the effect of terrestrial cosmic rays being key, it is thus also important to investigate the effect of the natural radiation on the cryopreserved stem cell behavior over time. Our study showed that the cryostored stem cells totally shielded from cosmic rays had less DSBs upon long-term storage. This could have important implications on the long-term cryostorage strategy and quality control of different cell banks.

Do the polyphenolic compounds from natural products can protect the skin from ultraviolet rays?

Excessive exposure to the sun is a major cause that augment the skin cancer, erythema, edema, abnormal pigmentation and finally suppress the immune system. Due to stratospheric ozone depletion and climate change UV levels are increasing, there is an urgent need to protect human skin from the harmful effects of UV. Compounds with photo- protection activity are very useful in reducing the effect of ultraviolet rays. For this reason, today’s sunscreens that contain one or more different types of chemical filters are used to protect the skin from ultraviolet rays. In the market, several synthetic, UV filter molecules are available, but they have limited use because these active molecules may create adverse effects on human skin such as, cancer, estrogenic activity, or photosensitivity reactions, contact dermatitis, mutations. Therefore, the development of formulations containing plant extracts and algae that may be potentially safer is being extensively studied. For this purpose, we can refer to polyphenol compounds such as flavonoids, which are a branch of natural substances that act as catalysts in the optical phase of photosynthesis, and act as anti-stress agents in plants by removing oxygen free radicals. Natural flavonoids have light and direct protection potential due to their ability to absorb ultraviolet rays and due to their antioxidant ability, as well as anti-inflammatory and immune modulating agents. In this article, the sun photoprotection properties of compounds with polyphenolic structure such as flavonoids derived from plant extracts or algae, as well as new methods in optimizing skin protection products against UV radiation have been investigated.

Fin Ray Crossbeam Angles for Efficient Foot Design for Energy‐Efficient Robot Locomotion

Energy-Efficient Robot Locomotion In article number 2100133, Poramate Manoonpong and co-workers present an integrative approach, combining 3D printing with soft material, finite element modeling, and neural control, to investigate the Fin Ray effect at various crossbeam angles and demonstrate that, among other angles, the Fin Ray model with nonstandard 10°-inclined crossbeams has a greater contact area to a curved surface and better durability. Using this 10° angle for efficient foot design can enhance on-pipe robot locomotion efficiency.

Fin Ray gripper for handling of high temperature hybrid forging objects

Universal handling systems are getting more and more relevant nowadays. Their unique ability to adapt to different objects and their various shapes enable cost savings by minimizing the number of handling systems and reducing set-up times. Furthermore, the mentioned aspects are advantageous for the hybrid forging manufacturing process, where the objects change their geometry several times. However, this work deals with the discrepancy between universal gripper, consisting mostly of polymer materials and the high temperature of the forging objects. Universal grippers are predominantly made of monolithic elastic material to achieve high functionality. However, the material has the disadvantage of only being applicable in a small temperature range, whereby the forging process reaches temperatures of up to 1200 °C. One type of monolithic grippers are so called Fin Ray grippers that use fingers based on the Fin Ray effect to close around objects when they encounter them. This adjustment takes place passively, requiring a minimum of actuation, which is advantageous for use at high temperatures. Therefore, we have designed a Fin Ray finger made of heat-resistant bulk material to close the mentioned gap. Our design consists of rigid links connected with joints providing shape variability. The thermal condition was taken into account as the temperature of the objects reaches up to 1200 °C. Thereby, temperature-related effects occur, such as thermal expansion, which strongly influence the design of the finger. To investigate this, a thermal simulation is used. Furthermore, an investigation of the adaptability is carried out based on a multi-body FEM simulation. In this process, the finger is specified in an iterative process based on hybrid demonstrator components.