Effect of Organic Additives on Silicon Combustion in Nitrogen

The work shows some peculiarities of silicon combustion in nitrogen in the presence of additives of organic compounds. Organic compounds with different composition were used. Combustion of samples was carried out in a constant-pressure bomb. The combustion products are composite powders and containing α-, β- Si3N4, SiC, Si2N2O. The addition of organic additives suppressed coagulation of Si particles, improved the extent of conversion, and promoted combustion of coarse Si powders which can’t be ignited by any other methods. Introduction of organic dopants to Si powders was found to intensify their combustion without significant influence on the combustion temperature. Active transition of silicon to the gas phase occurs in the low-temperature zone of the combustion wave at the temperature lower than the melting point of silicon. At the temperatures lower than the melting point of Si the quenched combustion products contain two types of crystals of SiC and Si3N4. SiC is formed within a low-temperature zone of the combustion wave. SiC is formed by fine crystals and large spherical particulates which are formed by a bunch of very thin web-like crystals. SiC and Si3N4 formation provides a protective coating on silicon particles. It prevents coagulation at the temperature increase. The experiments have proved that it is enough to introduce 1-7 M of the organic additive to 1000 M of silicon for the combustion initiation. Meanwhile, adding different inorganic salts, including ammonium chloride, did not promote combustion. After initiation of combustion to continue Si powder must contain additives or organic compounds or addition of carbon black; carbon black is necessary for keeping the combustion on

Influence of parental compliance on the effectiveness of treatment of chronic gastroduodenal pathology in children

The article focuses on the studies which point to particular difficulties in achieving compliance in pediatrics. A dangerous trend to escalate the number and doses of antibiotics in anti- Helicobacter pylori (HP) schemes, the dosage frequency and course duration of eradication therapy considerably complicates a patient’s compliance to the treatment and contributes to a further growth of HP antibiotic resistance. In the treatment of children, the control of the outpatient therapy largely depends on the patient’s parent

Development of a Li2MoO4 scintillating bolometer for low background physics

We present the performance of a 33 g Li2MoO4 crystal working as a scintillating bolometer. The crystal was tested for more than 400 h in a dilution refrigerator installed in the underground laboratory of Laboratori Nazionali del Gran Sasso (Italy). This compound shows promising features in the frame of neutron detection, dark matter search (solar axions) and neutrinoless double-beta decay physics. Low temperature scintillating properties were investigated by means of different alpha, beta/gamma and neutron sources, and for the first time the Light Yield for different types of interacting particle is estimated. The detector shows great ability of tagging fast neutron interactions and high intrinsic radiopurity levels (< 90 \muBq/kg for 238-U and < 110 \muBq/kg for 232-Th).Comment: revised versio

The influence of Losartanum and Amlodipinum fixed combination use on cardiovascular complications risk factors seasonal variability in patients with arterial hypertension

Rationale: The influence of drugs on adaptation to high temperatures and seasonal variability of cardiovascular disease factors is one of the most important issues of treatment raised during re-cent heat waves. The safety of calcium channel blockers (CCBs) and angiotensin II receptor blockers (ARBs) use during heat waves is quite controversial. Aim: To assess the seasonal variability of hemodynamic parameters, vessel wall stiffness, lipid, carbohydrate and electrolyte metabolism in patients with arterial hypertension (AH) and to as-sess safety and effectiveness of fixed combination of Losartanum and Amlodipinum (Lortenza® KRKA) use according to one-year follow-up results. Materials and methods. The study included 26 patients with stage 1 and 2 AH aged from 42 to 81 years. Office blood pressure measurement, electrocardiography, volumetric sphygmography (pulse-wave velocity, cardio-ankle vascular index), serum chemistry, blood osmolarity tests were performed. Visual Analog Scale (VAS), Heat Questionnaries and self-control diaries were also assessed. The baseline visit took place in spring of 2016, the first visit - in May-June 2016, the second - during the heat wave, the third - in September-October 2016, the fourth - in January-February 2017, and the fifth - in April-May 2017. Results. The treatment resulted in systolic and diastolic blood pressure decrease (р=0.000) to target value which persisted during the follow-up period. According to the self-control diaries 81% of patients did really control BP. During the heat wave only 58% of patients succeeded in BP control, in autumn - 63%, in winter and spring - 81% and 86%, respectively. By the third visit the heart rate decreased on -6.0 (-11.1; -2.8) beats per minute, p=0.007. The decrease in pulse-wave velocity from 15.2±3.4 m/s to 13.6±2.7 m/s, p=0.01 and CAVI on -2.1 (-2.9; -0.65), p=0.01 was observed on the third visit. Decrease in uric acid level (

Interleukin-18 gene polymorphism in pregnancy With premature rupture of membranes: A case-control study

Background. Imbalanced pro- and anti-inflammatory systems can unfavourably condition carrying of pregnancy and provoke gestation complications, such as premature rupture of membranes.Objectives. Assessing the contribution of SNP variants -137G&gt;C (rs187238), -607G&gt;T (rs1946518) and -656A&gt;C (rs5744228) of the IL-18 gene promoter to the incidence of extremely preterm premature rupture of membranes.Methods. A case-control study enrolled 120 pregnant women managed at the Perinatal Centre. The women were divided in two cohorts. The study cohort comprised 80 women with premature rupture of membranes at 22–27 weeks 6 days’ gestation hospitalised in a high-risk pregnancy unit, a control cohort consisted of 40 women with physiological pregnancy at 22–27 weeks 6 days’ gestation following outpatient counselling. The cohorts had comparable obstetric and gynaecological histories. The study exclusion criteria were: multiple gestation, foetal chromosomal anomalies, congenital foetal malformations, pregnancy due to assisted reproduction. Genotyping was performed at positions -137G&gt;C, -607G&gt;T and -656A&gt;C of the IL-18 gene promoter with determining a peripheral blood IL-18 level in cohorts.Results. The premature rupture of membranes cohort had a statistically higher serum interleukin-18 concentration compared to control (p = 0.001). Genotyping of the IL-18 gene promoter revealed a statistically higher rate of homozygous -137G&gt;C mutation (CC genotype) in the premature rupture of membranes cohort at 22–27 weeks 6 days’ term (p &lt;0.001), 67 vs. 27% in control.Conclusion. A homozygous IL-18 -137G&gt;C polymorphic variant associated with elevated blood IL-18 levels is statistically more common in pregnant women having premature rupture of membranes at 22–27 weeks 6 days’ gestation

Observation of Cosmic Gamma Ray Bursts in the Experiments Onboard Lomonosov and Vernov Satellites

Abstract: The study of cosmic gamma ray bursts (GRBs) is one of the main goals of the Lomonosov space mission. The main advantage of this mission is simultaneous multiwavelength observations of GRBs covering the optical, X-ray and gamma-ray ranges. The mission payload includes the GRB monitor BDRG, wide-field optical cameras SHOK, and the UFFO instrument. Data are recorded mainly by the event trigger provided by the BDRG instrument, which measures the spectral and temporal properties of the burst in the energy range 10–3000 keV. The BDRG instrument also provides estimation of the source coordinates by comparing the readings of three differently directed detectors with an accuracy of several degrees. Wide-field SHOK optical cameras have a field of view of ~20° × 40°. They fix a set of images with a frequency of about five frames per second prior to the trigger and another set immediately after the trigger. The UFFO instrument includes the UBAT telescope with a coded mask for measurements in hard X-ray and soft gamma-ray ranges and an optical telescope with a slewing mirror (SMT) that can be directed on the GRB source for a time ~1 s for measuring GRB prompt emission in the early stages. In response to an BDRG trigger signal, the real-time data on a detected GRB are transmitted to the Earth via Globalstar network to the Gamma-ray Coordinates Network (GCN) and ground-based observatories. During observations on the Lomonosov satellite, 20 gamma-ray bursts were detected and catalogued. Several gamma-ray bursts were also detected in the Vernov satellite experiment. An example of such an event is given.Financial support for this work was provided by the Ministry of Education and Science of the Russian Federation, project no RFMEFI60717X0175