Influence of plasticizer structure on stability of polystyrene scintillators optical characteristics

The radiation and thermal stability of optical characteristics of polystyrene scintillators modified by plasticizers based on derivatives of naphthalene, ditolylmethylene, diphenylene oxide, ether of phthalic acid and oligo-phenyl-methyl-siloxanes were studied. It was shown that structure and size of plasticizer molecule make a definite influence on scintillators characteristics of operational conditions stability

IN SILICO СРАВНИТЕЛЬНЫЙ АНАЛИЗ CRISPR-СИСТЕМ ШТАММОВ YERSINIA PSEUDOTUBERCULOSIS, ВЫЗЫВАЮЩИХ РАЗИЧНЫЕ КЛИНИЧЕСКИЕ ПРОЯВЛЕНИЯ ПСЕВДОТУБЕРКУЛEЗА

Цель: сравнить CRISPR-системы двух штаммов, вы- деленных на различных территориях от пациентов с разными клиническими проявлениями псевдотуберкуле- за, и определить специфические различия в спейсерном составе и в структуре cas-белков. Материалы и методы: проанализированы полногеном- ные последовательности штаммов Y. pseudotuberculosis IP329353 (NC_006155) и IP31758 (NC_009708) различного географического происхождения, выделенные от больных с псевдотуберкулезом с симптомами гастроэнтерита и системными проявлениями инфекции соответственно. Поиск, идентификация и анализ CRISPR систем выпол- нены с использованием онлайн-приложений CRISPROne, CRISPRDetect и CRISPRTarget. Результаты: в геноме исследуемых штаммов обнаруже- ны CRISPR-Cas системы, включающие один набор cas-генов и несколько CRISPR-локусов, значительно удаленных друг от друга. В геноме штамма Y. pseudotuberculosis IP329353 присутствует три локуса: YP1, находящийся в непосред- ственной близости от cas-генов, YP2 и YP3. CRISPR-Cas система Y. pseudotuberculosis IP31758 представлена только двумя кассетами: YP1 и YP3. CRISPR системы исследуемых штаммов не имеют одинаковых спейсеров. Заключение: CRISPR-Cas системы исследованных штаммов отличаются количеством CRISPR-локусов, их спейсерным составом и структурой cas-белков. Полу- ченные результаты определяют перспективу использо-вания CRISPR-локусов в качестве специфических молеку- лярных маркеров штаммов при изучении внутривидово- го разнообразия и эволюции Y. pseudotuberculosis.The aim of this research was to analyze and compare CRIPSR loci and cas-proteins of Yersinia pseudotuberculosis strains isolated in different territories from patients with various clinical manifestations of pseudotuberculosis. MATERIALS AND METHODS. Complete genomes of Y. pseudotuberculosis IP329353 (NC_006155) and IP31758 (NC_009708) were obtained from NCBI Nucleotide Database. Strains were isolated from patients with gastroenteritis and systemic infection respectively. Search, identification, and analysis of CRISPR systems were carried out by onlinetools CRISPROne, CRISPRDetect, and CRISPRTarget. RESULTS. Analyzed strains have CRISPR-Cas systems that include one set of cas-genes and arrays situated at the long distances from each other. We defined three CRISPR arrays in Y. pseudotuberculosis IP32953: array YP1 located near cas-genes, arrays YP2 and YP3. CRISPR-Cas system of Y. pseudotuberculosis IP31758 includes two arrays – YP1 and YP3. CRISPR systems do not share similar spacers. CONCLUSION. CRISPR systems of the analyzed strains differ in CRISPR loci and cas-protein structures that can be used as specific molecular marks of analyzed strains during the study of intra-species variability and evolution of Y. pseudotuberculosis.https://www.scimagojr.com/journalsearch.php?q=21100790112&tip=sid&clean=0am2019Biochemistr

Manufacture and study of new polystyrene scintillators

The main optical characteristics and radiation hardness of new polystyrene scintillator UPS98GC were studied. The scintillator UPS-98GC was compared to SCSN-81, produced by Kuraray Co. which is often used in high-energy physics experiments. The dependence of scintillator properties on radiation dose rates as well as on total dose values was studied. It is shown that for relatively small dose rates closed to those expected during scintillator lifetime, our UPS98GC does not yield to SCSN-81

Study of physical processes in laser-irradiated porous targets of different microstructure

New results obtained in experiments on laser irradiation (${\rm I}=10^{14}$ W/cm$^{2}$, ${\rm \lambda} =1.055 {\rm \mu}$m) of low-density (1-30 mg/cm$^{3})$ fibrous and foam-like materials are presented and discussed. The effect of low-density material microstructure of irradiated samples on physical processes in high-temperature plasma was investigated. Using a variety of complementary X-ray and optical methods the pronounced effect of material microstructure on the parameters and dynamics of produced plasma was found