Synthesis of polyamides from diamines of the fluorene series

Aromatic polyamides were prepared by polycondensation of isophthaloyl chloride and 2,7-diaminofluorene, 2,7-dimainofluorenone, or 2,5-diaminofluorenone in AcNMe2 or N-methyl-2-pyrrolidinone at 20 deg - 30 deg for 1.5-2 hr. Isophthaloyl chloride-2,5-diaminofluorenone copolymer 39609-29-51 was sol. in AcNMe2, N-methyl-2-pyrrolidinone, DMF, and hexamethylphosphoramide, whereas isophthaloyl chloride-2,7-diamino-fluorene copolymer 39609-30-3 and isophthaloyl chloride-2,7-diamino-fluorenone copolymer 39609-31-0 were not sol. in the solvents cited. The aromatic polyamides revealed thixotropic properties in 0.5% solutions in H2SO4

Effect of biochar on soil co2 fluxes from agricultural field experiments in russian far east

Agricultural soils are a major source of greenhouse gases. Biochar is a soil improver and, when applied to the soil, sequesters carbon. However, a different combination of soil and climatic conditions and biochar leads to different research results. In this research, the effects of 1 kg/m2 and 3 kg/m2 biochar application to clay soils on the CO2 flow in field experiments along two cropping seasons in the Russian Far East were investigated. Data showed that biochar significantly reduces the cumulative flow of soil CO2, compared with untreated field plots. In 2018, the greatest reduction in soil CO2 emissions (28.2%) with 3 kg/m2 of biochar was obtained, while in 2019, the greatest decrease in the cumulative CO2 flow at the application dose of 1 kg/m2 (57.7%) was recorded. A correlation between a decrease in the value of the cumulative CO2 flux and an increase in the biomass grown in the studied areas of agricultural crops during the season of 2018 was found

Measuring extensive air showers with Cherenkov light detectors of the Yakutsk array: The energy spectrum of cosmic rays

The energy spectrum of cosmic rays in the range 10^15 eV to 6*10^19 eV has been studied using the air Cherenkov light detectors of the Yakutsk array. The total flux of photons produced by relativistic electrons (including positrons as well, hereafter) of extensive air showers in the atmosphere is used as the energy estimator of the primary particle initiating a shower. The resultant differential flux of cosmic rays exhibits, in accordance with previous measurements, a knee and ankle features at energies 3*10^15 and ~10^19 eV, respectively. A comparison of observational data with simulations is made in the knee and ankle regions in order to choose the models of galactic and extragalactic components of cosmic rays which describe better the energy spectrum measured.Comment: 27 pages, 22 figures, accepted for publication in New Journal of Physics (Focus Issue

Variability of Sequence Surrounding the Xist Gene in Rodents Suggests Taxon-Specific Regulation of X Chromosome Inactivation

One of the two X chromosomes in female mammalian cells is subject to inactivation (XCI) initiated by the Xist gene. In this study, we examined in rodents (voles and rat) the conservation of the microsatellite region DXPas34, the Tsix gene (antisense counterpart of Xist), and enhancer Xite that have been shown to flank Xist and regulate XCI in mouse. We have found that mouse regions of the Tsix gene major promoter and minisatellite repeat DXPas34 are conserved among rodents. We have also shown that in voles and rat the region homologous to the mouse Tsix major promoter, initiates antisense to Xist transcription and terminates around the Xist gene start site as is observed with mouse Tsix. A conservation of Tsix expression pattern in voles, rat and mice suggests a crucial role of the antisense transcription in regulation of Xist and XIC in rodents. Most surprisingly, we have found that voles lack the regions homologous to the regulatory element Xite, which is instead replaced with the Slc7a3 gene that is unassociated with the X-inactivation centre in any other eutherians studied. Furthermore, we have not identified any transcription that could have the same functions as murine Xite in voles. Overall, our data show that not all the functional elements surrounding Xist in mice are well conserved even within rodents, thereby suggesting that the regulation of XCI may be at least partially taxon-specific

Early Loss of Xist RNA Expression and Inactive X Chromosome Associated Chromatin Modification in Developing Primordial Germ Cells

The inactive X chromosome characteristic of female somatic lineages is reactivated during development of the female germ cell lineage. In mouse, analysis of protein products of X-linked genes and/or transgenes located on the X chromosome has indicated that reactivation occurs after primordial germ cells reach the genital ridges.We present evidence that the epigenetic reprogramming of the inactive X-chromosome is initiated earlier than was previously thought, around the time that primordial germ cells (PGCs) migrate through the hindgut. Specifically, we find that Xist RNA expression, the primary signal for establishment of chromosome silencing, is extinguished in migrating PGCs. This is accompanied by displacement of Polycomb-group repressor proteins Eed and Suz(12), and loss of the inactive X associated histone modification, methylation of histone H3 lysine 27.We conclude that X reactivation in primordial germ cells occurs progressively, initiated by extinction of Xist RNA around the time that germ cells migrate through the hindgut to the genital ridges. The events that we observe are reminiscent of X reactivation of the paternal X chromosome in inner cell mass cells of mouse pre-implantation embryos and suggest a unified model in which execution of the pluripotency program represses Xist RNA thereby triggering progressive reversal of epigenetic silencing of the X chromosome

Conserving surgery for iatrogenic defects of the maxillary sinus

A rationale for the choice of the method of primary plastics perforation of the maxillary sinus defects of different etiology. The study Included 292 patients of both sexes aged 19-72 years who in the course of surgical intervention been opened maxillary sinus: at 80 - in the formation of access for the removal of cysts (30 in a conventional manner, endoscopic (FESS) - 30, osteoplastic by ultrasound NV Mishenkin • 30); In 212 - during the removal of the tooth (37 patients without restoring bone wall, 175 with the restoration of the authors' methodology with platelet plasma (patent 2,380,052). When using the osteoplastic ultrasonic method for accessing the maxillary sinus catarrhal, purulent and subatrophic changes in the nasal mucosa observed 4.5 times less than the traditional access and 3.8 times less than in FESS. results perforated plastic defect using the platelet plasma by the method of Al and AA Musienko 12 times better than traditional treatment group.Цель работы - обоснование выбора метода первичной пластики перфорационных дефектов верхнечелюстной пазухи различной этиологии. Под наблюдением находились 292 пациента обоего пола в возрасте 19-72 лет, у которых в процессе хирургического вмешательства вскрывалась верхнечелюстная пазуха: у 80-ти - при формировании доступа для удаления кисты (традиционным способом 30, эндоскопическим (ФЭСХ) - 30, остеопластическим ультразвуковым по Н.В. Мишенькину - 30); у 212 - во время удаления зуба (37 пациентам без восстановления костной стенки, 175 с восстановлением по авторской методике с тромбоцитарной плазмой (патент 2380052). При использовании остеопластического ультразвукового способа для доступа в верхнечелюстную пазуху катаральные, гнойные и субатрофические изменения слизистой оболочки полости носа отмечались в 4,5 раза реже, чем при традиционном доступе и в 3,8 раза реже, чем при ФЭСХ. Результаты пластики перфоративного дефекта с использованием тромбоцитарной плазмы по методике А.И. И А А Мусиенко в 12 раз лучше, чем в группе традиционного лечения

Применение идаруцизумаба при выполнении экстренных хирургических вмешательств пациентам, принимавшим дабигатран

This article presents modern possibilities for the provision of emergency surgical care to patients with atrial fibrillation, who administered dabigatran etexilate. We describe two clinical situations, in which idarucizumab, a specific dabigatran antagonist, which is a monoclonal antibody fragment that binds dabigatran, was used to neutralize the anticoagulant effect of dabigatran etexilate before emergency surgery. In the first case, the patient developed acute gangrenous calculous cholecystitis, in the second a patient required an urgent epicystostomy. In both cases, the successful outcome of surgical interventions was due to the effective interactions of the team of specialists and adherence to the algorithm for providing emergency care to such patients, as well as the presence of idarucizumab in hospitals. The postoperative management of patients and the timely resumption of anticoagulant therapy to prevent thromboembolic complications is no less important. The presented clinical cases confirm the feasibility of using idarucizumab to provide emergency surgical care to patients on dabigatran etexilate, as well as the need to take into account the possible risk of emergency interventions when anticoagulant therapy is prescribed to patients with atrial fibrillation. This paper discusses special risk groups of patients in whom rapid reversal of anticoagulation is required due to altered hemostasis.We outline data of a prospective cohort study (RE-VERSE AD), which examined the efficacy and safety of idarucizumab in patients with uncontrolled bleeding and in patients requiring urgent surgery. We also present the RE-VECTO study data on the use of idarucizumab in real-life clinical practice.В статье представлены современные возможности оказания экстренной хирургической помощи пациентам с фибрилляцией предсердий, принимавшим дабигатрана этексилат. Описаны две клинические ситуации, в которых перед экстренным хирургическим вмешательством для нейтрализации антикоагулянтного эффекта дабигатрана этексилата был применен его специфический антагонист – идаруцизумаб, представляющий собой фрагмент моноклонального антитела с высокой связывающей активностью в отношении дабигатрана. В первом случае у пациента развился острый гангренозный калькулезный холецистит, во втором больному потребовалось экстренное наложение эпицистостомы. В обоих случаях успешный исход оперативных вмешательств был обусловлен эффективным взаимодействием команды специалистов с соблюдением алгоритма оказания неотложной помощи таким пациентам, а также наличием в стационарах идаруцизумаба. Не менее важными являются послеоперационное ведение пациентов и своевременное возобновление антикоагулянтной терапии для профилактики тромбоэмболических осложнений. Представленные клинические случаи подтверждают целесообразность применения идаруцизумаба при оказании экстренной хирургической помощи пациентам, принимавшим дабигатрана этексилат, а также необходимость учитывать возможный риск неотложных вмешательств при назначении антикоагулянтной терапии у пациентов с фибрилляцией предсердий. В представленной работе обсуждаются группы пациентов особого риска, которым может потребоваться экстренная реверсия антикоагулянтной активности на фоне измененного гемостаза. Представлены данные проспективного когортного исследования RE-VERSE AD, в котором были изучены эффективность и безопасность идаруцизумаба у пациентов с неконтролируемыми кровотечениями и у пациентов, которым требовалось ургентное оперативное вмешательство. Также представлены данные исследования RE-VECTO об использовании идаруцизумаба в реальной клинической практике

RESEARCH DIFFERENT FUEL REAGENTS FOR THE SYNTHESIS OF NANOSTRUCTURED POWDERS ZrO2-Y2O3

In this work a study of obtaining nanostructured powders with various fuel reagents is described

THE STUDY OF THE MORPHOLOGY OF PARTICLES OF MICRON POWDERS ZrO2 -7 WT.% Y2O3 WITH DIFFERENT BULK DENSITY

The morphology of the powder particles was studied. Their regular spherical shape was determined and the effect of the specific surface and pore diameter on the bulk density was established

CERTIFICATION OF MICRON POWDERS ZrO2 -7 WT.% 2 3 Y O OF DIFFERENT BULK DENSITY

Properties of spheroidized 2 2 3 ZrO 7%Y O powders with different bulk density values have been determined. The dependence of bulk density with the granulometric composition and flowability of powders is established