Small-Molecule Mn Antioxidants in Caenorhabditis elegans and Deinococcus radiodurans Supplant MnSOD Enzymes during Aging and Irradiation

The current theory of cellular defense against oxidative damage identifies antioxidant enzymes as primary defenders against ROS, with MnSOD being the preeminent superoxide (O 2 •− ) scavenger. However, MnSOD is shown to be dispensable both for radiation resistance and longevity in model organisms, the bacterium Deinococcus radiodurans and the nematode Caenorhabditis elegans .

General approaches to assessing the resistance to the effects of ionizing radiation of outer space for foreign electronic component base of development enterprises

The analysis of information on the stability of the electronic component base (ECB) in the development of radio-electronic equipment (REE) of spacecraft (spacecraft) is an important and urgent task. The paper considers the main components of the approaches of foreign organizations developing radio space technology to ensure its radiation resistance. The design approaches of Thales Alenia Space, Airbus Defense and Space, and the European Space Agency are presented. The article outlines the main directions for optimizing the procedures for the preliminary selection of ECB, which consist in ensuring the required resistance of REE SC at the ECB level with ensuring the reliability of data on durability, in minimizing the costs of applying resistance enhancement measures (through the use of a promising ECB with increased resistance characteristics), to replace ECB.

Methods for detecting and correcting errors in irregular structures under the influence of heavy charged particles

The paper considers methods of increasing the durability of radio-electronic equipment in space, namely, methods of detecting and correcting errors during the action of the HCP. Currently, redundancy methods are used to ensure durability, when two or three processors work in parallel in the system, and a special node compares the results of their work. If the results do not match, an error signal will be generated, and the system will begin to perform actions to correct it. The article describes and classifies the main circuit, structural-functional, algorithmic methods for detecting and correcting errors. It is shown that circuit solutions lead to an increase in the crystal area. Therefore, the problem arises of ensuring radiation resistance with a minimum increase in the crystal area.

DIRAS2 Contributes to Radiation Resistance of Renal Cell Carcinoma Via Autophagy Induction and MKK4-JNK1 Pathway Activation

Radiation resistance has been regarded as a main obstacle to improve the definitive treatment of renal cell carcinoma (RCC), of which clear cell RCC (ccRCC) is the most common histological type. However, the molecular mechanism underlying the radiation resistance remains largely unclear. In this study, we investigated the effect of DIRAS2 on the response to ionizing radiation (IR) in human ccRCC cells. Here, we found the expression level of DIRAS2 was significantly upregulated in human ccRCC tissues using the Oncomine platform and the Cancer Genome Atlas (TCGA) database, which was further validated by immunohistochemistry. Overexpression of DIRAS2 promoted radiation resistance of ccRCC cells based on clonogenic survival assay and enhanced the levels of radiation induced-autophagy. Moreover, inhibition of autophagy by chloroquine (CQ) pre-treatment largely eliminated the effect of DIRAS2 overexpression on radiation-resistance. Finally, molecular mechanism investigation showed that overexpression of DIRAS2 upregulated the activity of mitogen-activated protein kinase (MAPK) kinase 4 (MKK4)- c-Jun NH2-terminal kinase 1 (JNK1)-Bcl-2 pathway in response to IR. Taken together, these results indicate that DIRAS2 may confer radiation resistance on human RCC via autophagy induction through MKK4-JNK1-Bcl-2 signaling pathway.

CHARGE DISTRIBUTION IN THE AlO - SiO SYSTEM EXPOSED TO IONIZING RADIATION

Полупроводниковые МДП (металл - диэлектрик - полупроводник) структуры являются ключевыми элементами современной электронной техники, в том числе устройств работающих в условиях воздействия проникающих излучений. Одним из возможных подходов к уменьшению радиационных эффектов в МДП структурах является использование диэлектриков, которые уменьшают генерацию и накопление избыточного пространственного заряда в объеме диэлектрика. В работе исследована система диэлектриков AlO - SiO. Исследование показывает пригодность использования МДП структур, на основе системы диэлектриков, для формирования приборов с высокой радиационной стойкостью. Нанесение слоя AlO поверх слоя SiO улучшает рабочие характеристики МДП структур за счет повышения однородности параметров. Основной эффект влияния слоя AlO на параметры структур заключается в уменьшении механических напряжений на границе SiO-подложка. Захват ловушками электронов в AlO, компенсирует заряд захваченных дырок в AlO, и снижает паразитный ток через AlO. Metal-insulator-semiconductor (MIS) structures are key elements of modern electronic technology, including devices operating under conditions of exposure to penetrating radiation. One of the possible approaches to reducing radiation effects in MIS structures is the use of dielectrics, which reduce the generation and accumulation of excess space charge in the bulk of the dielectric. We investigated the system of dielectrics AlO - SiO. The study shows the suitability of using MIS structures based on a system of dielectrics for formation of devices with high radiation resistance. Applying a AlO layer on top of the SiO layer improves the performance of MIS structures by increasing the uniformity of parameters. The main effect of the influence of the AlO layer on the parameters of the structures is to reduce the mechanical stresses at the interface SiO -substrate. The trapping of electrons in AlO, compensates for the charge of the trapped holes in SiO, and reduces the parasitic current through AlO.

Investigation of the Influence of Gamma Radiation on Structural Transformations in Portlandcement Stone

The radiation resistance of concrete under the influence of large doses of gamma radiation was investigated. To study the behavior of concrete under the influence of gamma radiation, two series of samples were taken: оne was the reference sample, and the other was exposed to gamma radiation. The temperature of the irradiated samples during testing did not exceed 40 °C, the reference temperature was also accepted to be 40 °C. The dose of gamma radiation was 109 rad. Its value corresponds to the dose that concrete can receive when it comes into contact with high-level radioactive waste from the Shelter over 300 years. Characteristics of an industrial gamma radiation equipment are: radiation energy is 1.25 MeV and dose rate is 2 Mrad/h. The use of such equipment allows reaching a dose of 109 rad in less than a month, and 108 rad - in 4-5 days. Concretes that were 28 days old and stored under normal conditions were exposed to gamma radiation.

OPERATING CONDITIONS OF SPACE CHIPS

The issues of creating modern microelectronics for special purposes and the conditions of its operation are considered. The trends in the development of space-purpose microcircuits and their influence on radiation resistance are determined. The paper presents the main physical phenomena that dominate among the radiation effects in recent years. Reducing the characteristic sizes of VLSI elements leads to the appearance of new physical effects, for which it is necessary to develop new models, or improve existing ones.

DEVELOPMENT OF MEANS FOR MONITORING THE PARAMETERS OF MICROCHIPS FOR ASSESSING RADIATION RESISTANCE

This article discusses the technical means of monitoring the performance of a special-purpose ECB for experimental evaluation of radiation resistance, in the absence of test measuring equipment that allows you to control the areas of the most degraded degradation when exposed to ionizing radiation and heavy charged particles of outer space.