Обнаружение DGA доменов и предотвращение botnet средствами Q-обучения для POMDP

 An effective method for preventing the operation of computer network nodes for organizing a botnet is proposed. A botnet is a collection of devices connected via the Internet for the purpose of organizing DDoS attacks, stealing data, sending spam and other malicious actions. The described method implies the detection of generated domain names in DNS queries using a neural network with parallel organization of convolutional and bidirectional recurrent layers. The effectiveness of the method is based on the assumption that generated domain names are used to create a botnet for merging. Experiments confirm that the proposed neural network is superior to the accuracy of existing counterparts on the UMUDGA dataset. The estimation of the quality of recognition of generated domain names using ROC analysis is calculated for a trained neural network. The article also formulates a model for controlling detectors using a partially observable Markov decisionmaking process to block infected nodes of a computer network. The search for the optimal policy for the formulated model by means of Q-learning of value agents is proposed. A comparative analysis of the average, minimum and maximum value of actions taken by agents in the process of interacting with the environment is carried out. Предлагается эффективный метод предотвращения эксплуатации узлов компьютерной сети для организации botnet. Под botnet подразумевается совокупность устройств, объединенных через сеть Интернет с целью организации DDoS-атак, кражи данных, рассылки спама и других вредоносных действий. Описанный метод подразумевает детектирование сгенерированных доменных имен  в DNS-запросах с помощью нейронной сети с параллельной организацией сверточных и двунаправленных рекуррентных слоев. Эффективность метода базируется на предположении, что для создания botnet используют генерируемые доменные имена для объединения. Эксперименты подтверждают, что предлагаемая нейронная сеть превосходит точность существующих аналогов на наборе данных UMUDGA. Вычисляется оценка качества распознавания сгенерированных доменных имен с помощью ROC-анализа для обученной нейронной сети. В статье также формулируется модель управления детекторами с помощью частично наблюдаемого марковского процесса принятия решений для блокировки зараженных узлов компьютерной сети. Предлагается поиск оптимальной политики для сформулированной модели средствами Q-обучения ценностных агентов. Производится сравнительный анализ по средней, минимальной и максимальной ценности принимаемых агентами действий в процессе взаимодействия с окружением.

The analysis of methylation of DNA promoter of SFRP2 gene in patients with hyperplastic processes of the endometrium

The hyperplastic processes of the endometrium can arise not only against the background of excessive influence of estrogen, but also against the background of epigenetic damages that affect apoptosis, cell proliferation, differentiation, and adhesion, and DNA reparation. The aim of our study was to investigate and analyze the status of methylation of the promoter of SFRP2 gene in patients with hyperplastic processes of the endometrium. Materials and Methods: The study groups were the following: I — patients with endometrial hyperplasia (EH, n = 9); II — patients with endometrial intraepithelial neoplasia (EIN, n = 10), III — control groups: 1) with endometrial cancer (EC, n = 4), and 2) healthy women (n = 4). Determination of promoter methylation of SFRP2 gene was carried out by the semiquantitative method of methylation-specific PCR assay. Results: The maximum level of methylation of SFRP2 gene promoter had been revealed in patients with EC — 42.80 ± 3.55% (р < 0.05). The patients of the I group had the lowest values of methylation of SFRP2 gene promoter — 10.66 ± 0.85%, while in patients of the II group this indicator was higher — 20.60 ± 0.95% (р < 0.05). In healthy women of the control group, methylation of SFRP2 gene promoter was detected in none of the samples. Conclusion: The content of the methylated SFRP2 gene in endometrial tissue of patients with hyperplastic processes higher than 20–25% allows relate these women to the risk group of EC development and dictates the need of intensive observation of such patients

Digital receivers for low-frequency radio telescopes UTR-2, URAN, GURT

This paper describes digital radio astronomical receivers used for decameter and meter wavelength observations. This paper describes digital radio astronomical receivers used for decameter and meter wavelength observations. Since 1998, digital receivers performing on-the-fly dynamic spectrum calculations or waveform data recording without data loss have been used at the UTR-2 radio telescope, the URAN VLBI system, and the GURT new generation radio telescope. Here we detail these receivers developed for operation in the strong interference environment that prevails in the decameter wavelength range. Data collected with these receivers allowed us to discover numerous radio astronomical objects and phenomena at low frequencies, a summary of which is also presented.Comment: 24 pages, 15 figure

Epigenetic inactivation of gene SFRP5 at breast cancer

Метилирование генов играет важную роль в развитии опухолевых заболеваний. Одним из количественных методов оценки содержания метилированной ДНК в тканях опухолей может быть пиросеквенирование. Целью данного исследования была разработка пиросеквенирования для оценки метилирования ДНК гена SFRP5 в опухолях рака молочной железы. Анализ метилирования был проведен методом количественного пиросеквенирования с использованием прибора PSQ96 ID фирмы Qiagen. Установлено, что для определения содержания метилированной ДНК гена SFRP5 в образцах ткани аденокарциномы молочной железы можно использовать метод пиросеквенирования. Метод дает количественную оценку содержания метилированной ДНК в пробе ткани рака молочной железы. Содержание метилированной ДНК у больных раком молочной железы составляло (35,96±2,23) %, тогда как в образцах условно нормальной ткани молочной железы — (6,00±1,34) % (р≤0,001).Genes methylation plays an important role in the development of cancer. Pyrosequencing technology is one of the methods of quantitative evaluation of methylated DNA level in the tumor tissue. The aim of this study is to develop pyrosequencing to analyze SFRP5 gene methylation in breast cancer. It was performed by quantitative pyrosequencing using the device PSQ96 ID (Qiagen). It was found that pyrosequencing method may be used to evaluate the level of of SFRP5 gene methlated DNA in the adenocarcinoma samples. The method quantifies the level of methylated DNA in breast cancer samples. The methylation level of SFRP5 gene in breast cancer sample was (35.96±2.23)%, whereas the level of methylated DNA in normal breast tissue (6.0±1.0)% (р≤0.001)

Effects of molecular structure on the physical, chemical, and electrical properties of ester‐based transformer insulating liquids

This article presents the experimental studies carried out on the environmental friendly polyol ester insulating liquids to investigate the effect of molecular structure on the physical, chemical, and electrical properties. Six different polyol esters that can be produced from the transesterification of various methyl esters with neopentylglycol/trimethylolpropane alcohols were synthesized and compared with those of refined, bleached, and deodorized palm oil (RBDPO) and mineral transformer oil. The finding suggests that the physical properties like fire point, pour point, and viscosity are very much affected by the molecular weight and molecular composition of the polyol esters. The electrical properties are also highly influenced by the molecular structure‐related characteristics, such as the polarity, dipole polarization, carbon chain length, and degree of branching. The results confirm the findings of previous studies that the polyol esters and RBDPO have more polarity and dipole polarization compared to mineral oil. The experimental evidence showed that the newly synthesized insulating liquids have favorable thermal and electrical properties, thus suggesting that the insulating liquids have the potential to replace conventional insulating liquids to provide a more sustainable power system in the future

Fragmentation and Multifragmentation of 10.6A GeV Gold Nuclei

We present the results of a study performed on the interactions of 10.6A GeV gold nuclei in nuclear emulsions. In a minimum bias sample of 1311 interac- tions, 5260 helium nuclei and 2622 heavy fragments were observed as Au projec- tile fragments. The experimental data are analyzed with particular emphasis of target separation interactions in emulsions and study of criticalexponents. Multiplicity distributions of the fast-moving projectile fragments are inves- tigated. Charged fragment moments, conditional moments as well as two and three -body asymmetries of the fast moving projectile particles are determined in terms of the total charge remaining bound in the multiply charged projectile fragments. Some differences in the average yields of helium nuclei and heavier fragments are observed, which may be attributed to a target effect. However, two and three-body asymmetries and conditional moments indicate that the breakup mechanism of the projectile seems to be independent of target mass. We looked for evidence of critical point observable in finite nuclei by study the resulting charged fragments distributions. We have obtained the values for the critical exponents gamma, beta and tau and compare our results with those at lower energy experiment (1.0A GeV data). The values suggest that a phase transition like behavior, is observed.Comment: latex, revtex, 28 pages, 12 figures, 3tables, submitted to Europysics Journal