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Over a period of 5 years, there was conducted a series of trials on the use of γ-irradiation of the female gametophyte of spring common wheat before remote hybridization with maize to study the effect of the phytohormonal changes during irradiation at various doses on ovaries’ growth after pollination with maize. Optimal timing of work on castration, irradiation, and pollination with maize pollen were established. It has been concluded that it is necessary to conduct such experiments in controlled conditions of a climatic chamber to avoid additional stress during fertilization and development of an embryo. The best results in ovaries’ growth were obtained (7.89–11.30 % of developed ovaries) with γ-irradiation in the dose from 3 to 15 Gy. There have been found changes in the level of various phytohormones and the possible influence of these changes on ovaries’ setting and growth, as potential sources of haploid and apomictically developed genotypes. The variants with the best indicators of developed ovaries are characterized by an increase in the ratio values of the salicylic acid/indole-3-acetic acid and salicylic acid/abscisic acid in relation to the same values before irradiation.

Relevance. Hemorrhagic fever with renal syndrome (HFRS) is leading among natural focal human diseases in Russia, the causative agents of which - orthohantaviruses - belong to the order Bunyavirales, family Hantaviridae. More than 98% of HFRS cases in Russia are caused by the Puumala virus. It is a serious zoonosis for which there is still no specific treatment. The WHO has not approved a vaccine. The aim of this study was to investigate the effect of formaldehyde, β-propiolactone, hydrogen peroxide, ultraviolet rays, gamma irradiation and thermal inactivation on the immunogenic activity of inactivated vaccine preparations against HFRS Materials and methods. To achieve this aim, experimental vaccine preparations based on the PUU-TKD/VERO strain of Puumala virus were prepared and inactivated using the methods described above. The time intervals required for complete inactivation of the virus were determined, and the effects of the inactivators on viral RNA and immunogenic activity of the vaccine preparations were evaluated in BALB/c mouse and Syrian hamster models. Results. According to our results, vaccine preparations inactivated by different chemical and physical methods, which differ significantly in the mechanism of the mechanism of interaction with the virus, show no significant differences in immunogenic activity, except for thermal inactivation. Conclusion. A certain advantage of β-propiolactone is the short virus inactivation time, its complete degradation into non-toxic compounds within a few hours, and the reduction of total protein content after sterilization filtration, which is probably due to less aggregation of virus particles and cellular proteins

One of the aspects important for strain collection maintenance is the optimization of existing methods and development of new techniques for microbial strain preservation, that is why the improvement of previously developed methods for authentic strain preservation is an urgent task. The article provides information on the maintenance of Burkholderia mallei 5584 (Master seed) using previously developed technique, which was supplemented with new stages in accordance with modern requirements for strain collections of highly dangerous disease agents. The previous strain maintenance technique involved its storage in its native state, which facilitated accumulation of genetic mutations and, ultimately modification of bacterial cell properties. To extend the storage time of this strain and to ensure the stability of its biological properties, the freeze-drying method was used. Skimmed milk was used as a cryoprotectant. Freeze-drying was performed under selected conditions. This technique allows for the strain sub-culturing on sensitive models once every 5 years, which is more expedient and safe from an economic and biological point of view. For safe handling of Burkholderia mallei 5584 production strain, an inactivation technique using gamma rays at 30 kGy was developed, which allowed to achieve microbial suspension sterility and preserve the bacterial cell structure. When comparing the previously developed and supplemented techniques, it was found that the improved technique of Burkholderia mallei 5584 (Master seed) maintenance makes it possible to avoid the loss of its biological properties needed for the production of high-quality laboratory diagnostic agents used for timely disease detection in susceptible animals by diagnostic tests.

This paper describes selected chemical, physical and analytical composition of fresh chicken egg (FCE), whole egg powder (WEP), and irradiated whole egg powder (IWEP). WEP samples were irradiating at 0, 5, 10 and 15 kGy using gamma irradiator. Analysis determined the approximate compositions, chemical and physical properties including the percentage of moisture, crud fat, crude protein, total sugar, reducing sugar, and ash, total acidity, pH value, total volatile basic nitrogen (TVBN), viscosity and color changes in FCE, WEP and IWEP. The results indicate that the FEP and WEP could be a fine resource of nutrients for consumers to select. In general, no considered differences observed in proximate components of WEP and IWEP. The results shows some differences in the analyzed chemical and physical parameters between WEP and IWEP. However, the tested physical and chemical parameters were all well within the acceptable limits for samples of FCE, WEP and IWEP.

Background. Currently, GaN/InGaN heterostructures are the main element base of modern optoelectronics. The widespread use of InGaN-based structures causes high reliability requirements. In order to ensure high reliability of photostructures, it is necessary to understand the mechanisms of radiative and non-radiative recombination, degradation mechanisms in these materials, and, consequently, to understand the nature of internal defects that affect the electrical and optical characteristics of LEDs. An important place is given to the study of the radiation resistance of heterostructures based on InGaN/GaN, which is associated with the ability to reveal the nature of defects existing in the studied samples, to investigate the effect of detected defects on the effectiveness of LED structures. The purpose of this work is to study the effect of gamma radiation on the electrical characteristics of LED structures based on InGaN/GaN blue glow. Materials and methods. Blue LEDs based on InGaN/GaN (wavelength at room temperature 470 nm) are being investigated. To achieve this goal, direct and reverse volt-ampere characteristics were measured on an automated measuring unit in the range of gamma radiation doses of 0–0.4 MRad. The methods of recombination spectroscopy and nonstationary deep-level spectroscopy were used to explain the detected changes in the volt-ampere characteristics. Results. It is established that the main mechanism of current transfer in the voltage range up to 2.5 V for the studied structures is tunneling. In the same voltage range, the dependence of the forward and reverse current on the dose of gamma radiation is observed: at 0.2 MRad, there is a decrease in current relative to the unirradiated sample, at 0.4 MRad, an increase in current relative to the unirradiated sample. Recombination spectroscopy and unsteady spectroscopy of deep levels revealed a level with an energy of 0.6 ± 0,02 eV involved in the creation of a tunnel flow. Conclusions. Using a generalized recombination model, it is shown that the magnitude of the tunnel current depends on the concentration of deep centers that create energy levels in the forbidden zone. The recombination spectroscopy method (according to the dependence d f (U ) dU β = , where β is the differential indicator of the slope of the voltampere characteristics) established the effect of gamma irradiation on the concentration of deep levels involved in the creation of a tunnel flow. It is shown that at a dose of 0.2 MRad, the amplitude of the extremum decreases, and at 0.4 MRad increases, which is consistent with the behavior of forward and reverse tunneling.

The aim of this work was to compare the fatty acid (FA) composition of oil from irradiated and un-irradiated cherry kernels (ChK). Cherry kernel were exposed to radiation doses of 0, 3 and 6 kGy of gamma irradiation covering the range for insect/pest disinfestations and for microbial load. The FA composition of cherry kernel oil (ChKO) was analyzed with using gas chromatography analysis. Oleic acid (C18:1) was consistently present in the highest quantity with averaged 51.07% of the total FA. The FA existing in second highest quantity was linoleic acid (C18:2) showing 38.03% on the average, followed by palmitic acid (C16:0) averaged 7.71%, stearic acid (C18:0) averaged 2.41%, palmitic acid (C16:1) averaged 0.42%, and linolenic acid (C:18:3) averaged 0.38%. indicating that it can be used for human consumption. In the present study, Palmitic, stearic, oleic, linoleic and linolenic acid, SFA and USFA were not affected by irradiation or storing. Conclusively, the ChKO may have sufficient oil volume potential to be used as edible (domestic) and industrial oil.

Background: Oil seeds are among the major food commodities that can be affected by microorganisms, which are produced by a particular type of mold. Ionizing radiations are also used to reduce pathogen propagation when trading these products. Methods: To investigate the effect of gamma irradiation and storage on quality of shelf-life of sunflower seed, samples of the seeds obtained from the market have been irradiated under 3, 6, and 9 kGy of gamma radiation and stored for 12 months. Results: The results indicate that, all used doses of gamma irradiation had no significant (p

The calibration dependence of dicentrics and rings chromosomes with an accompanying fragment induction in human lymphocytes by in vitro 137Сs acute gamma irradiation of blood in the dose range of 0.09 - 1.0 Gy is presented. The application of the obtained calibration curve for estimation of “biological” doses for overexposed 9 persons from the contract staff of the Chornobyl SSE is shown. Their doses calculated by the frequency of dicentrics and centric rings with consideration of operation duration and mode in the zone of influence of the radiation factor, significantly exceeded the doses determined by the methods of physical dosimetry.

The yield of agricultural crops depends largely on the seeding qualities of the seeds. In this regard, in order to increase productivity, methods are used to increase the sowing qualities of seeds. These methods are quite diverse and include treatment of seeds with various chemicals, current and magnetic field treatment, as well as irradiation of seeds before sowing with electromagnetic waves. This article is of an overview nature and is devoted to methods of pre-sowing treatment of seeds in order to increase their germination, namely, the effect on seed germination of irradiation of their waves of different lengths. Thearticle considers the influence of four types of irradiation on crop quality: UV irradiation, laser irradiation, gamma irradiation, and UHF irradiation.

This work is devoted to the study of the mechanisms of the influence of radiation defects, arising under the influence of gamma irradiation, on the change in resistivity ρ, lifetime of nonequilibrium electrons τn and holes τp, in CdTe:Cl and Cd0.9Zn0.1Te as well as the collection efficiency η of uncooled radiation detectors based on these materials, by computer simulation method. Radiation defects, that are corresponded by deep energy levels in the band gap, act as trapping centers of nonequilibrium charge carriers, noticeably affect the degree of compensation by changing ρ of the detector material, the recombination processes by decreasing τn and τp, what ultimately can cause degradation of the charges collection efficiency η. The specific reasons for the deterioration of the detector properties of CdTe:Cl and Cd0.9Zn0.1Te under the influence of gamma irradiation were identified, and the main factors leading to complete degradation of the recording ability of detectors based on these semiconductors during their bombardment by 60Co gamma quanta were determined. The gradual degradation of the spectroscopic performance of CdTe:Cl-based detectors during gamma irradiation occurs due to the continuous formation of cadmium vacancies VCd and acceptor complexes VCd – Cl, which continuously shift Fermi level towards valence band and decrease ρ. The complete performance degradation of CdTe detectors takes place mainly due to the capture of nonequilibrium electrons at energy level of interstitial tellurium Te(I). The invariable spectroscopic properties of CdZnTe-based sensors under gamma irradiation up to 25 kGy occur due to the mechanism of radiative self-compensation by formation of substitutional defect TeZn. At the final stage of irradiation, a sharp deterioration in the detector properties of CdZnTe occurs, mainly due to the capture and recombination of nonequilibrium charge carriers at the level of the Te(I) defect. The different radiation resistances of CdZnTe and CdTe:Cl can be explained by different behavior of Fermi level EF in these semiconductors under gamma irradiation. EF in CdZnTe under radiation exposure remains near the middle of band gap, and in CdTe it drifts to the valence band. The rate of capture and recombination through Te(I) donor level in CdTe:Cl is lower than in CdZnTe due to the larger difference between the Fermi level and the radiation defect Te(I) level in cadmium telluride. Thereby, the complete degradation of the CdTe:Cl detector occurs at a higher concentration of radiation defect Te(I), and hence after a higher irradiation dose of 50 kGy compared with a dose of 30 kGy required for degradation of CdZnTe detector properties.

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Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An influence of g-irradiation (Co60) with doze up to 1—1018 сm–2 and magnetic field with induction up to 14 T on conduction of 1–xGex (х = 0,03) whisker crystals with resistivity of 0,08—0,025 Оhm·сm in temperature range 4,2—300 K have been studied. It is shown that whisker crystals resistance faintly varies under irradiation with doze 2·1017 сm–2, while their magnetoresistance substantially changes. The strain sensors stable to irradiation action operating in high magnetic fields on the base of the whiskers have been designed.