Slope stability monitoring from microseismic field using polarization methodology

International audienceNumerical simulation of seismoacoustic emission (SAE) associated with fracturing in zones of shear stress concentration shows that SAE signals are polarized along the stress direction. The proposed polarization methodology for monitoring of slope stability makes use of three-component recording of the microseismic field on a slope in order to pick the signals of slope processes by filtering and polarization analysis. Slope activity is indicated by rather strong roughly horizontal polarization of the respective portion of the field in the direction of slope dip. The methodology was tested in microseismic observations on a landslide slope in the Northern Tien-Shan (Kyrgyzstan)

Prediction and measurement of radiation damage to CMOS devices on board spacecraft

The CMOS Radiation Effects Measurement (CREM) experiment is presently being flown on the Explorer-55. The purpose of the experiment is to evaluate device performance in the actual space radiation environment and to correlate the respective measurements to on-the-ground laboratory irradiation results. The experiment contains an assembly of C-MOS and P-MOS devices shielded in front by flat slabs of aluminum and by a practically infinite shield in the back. Predictions of radiation damage to C-MOS devices are based on standard environment models and computational techniques. A comparison of the shifts in CMOS threshold potentials, that is, those measured in space to those obtained from the on-the-ground simulation experiment with Co-60, indicates that the measured space damage is smaller than predicted by about a factor of 2-3 for thin shields, but agrees well with predictions for thicker shields

Thermally stable composite system Al2O3-Ce 0.75Zr0.25O2 for automotive three-way catalysts

Present-day three-way catalysts operate in contact with exhaust gases whose temperature is as high as >1000 C, so the problem of developing thermally stable catalytic compositions is still topical. A series of Al2O 3-Ce0.75Zr0.25O2 composites containing 0, 10, 25, and 50 wt % Al2O3 has been synthesized by direct precipitation. The as-prepared composites and those calcined in air at 1000 and 1100 C have been characterized by BET, X-ray diffraction, transmission electron microscopy, and temperature-programmed reduction methods. The composites aged at 1050 C in a 2% O2 + 10% H2O + 88% N2 atmosphere have been used to prepare monolith catalysts, and the oxygen storage capacity (OSC) of the latter has been measured using a gas analysis setup. As the proportion of Al2O 3 in the composite is raised, the mixing uniformity and degree of dispersion of Ce x Zr1-x O2-δ particles increase, their chemical composition becomes homogeneous, and the amount of cerium involved in oxidation and reduction increases. The composite containing 50 wt % Al2O3 is a mixture of Ce x Zr 1-x O2-δ and Al2O3 crystallites, whose size is practically unaffected by calcination. The (Pt/Al2O3 + Al2O3-Ce 0.75Zr0.25O2) based on this composite has the highest OSC and is the most active. For this reason, full-scale testing of this catalyst is recommended. © 2013 Pleiades Publishing, Ltd

Fatty acid composition of tissue lipsds goslings and goose embryons

The changes in the fatty acid composition of the lipid in the brain tissues and geese liver and their embryos from 22-th embryonic day until 14-th day of postnatal period have been investigated. The fatty acid composition of tissues was quantified by methods of gas-liquid chromatography. The index of fatty acids unsaturation was calculated as equivalent concentration of unsaturated fatty acids relative to double bonds. Experience has shown that in the brain of geese high content of unsaturated fatty acids and level of their unsaturation occurs in 22-day-old embryos. From the 22nd to 28th day of embryogenesis the total content of unsaturated fatty acids in the brain tissues of embryos has decreased by 37.3 %, and the level of unsaturation of fatty acids — by 44.4 %. The transition to postnatal development (from the 28th day of embryogenesis to 1 st day of postnatal period) was characterized by a stable content of unsaturated fatty acids in the brain. However, the degree of unsaturation of fatty acids has decreased by 8.0 %. The content of unsaturated fatty acids in the liver of 22-days embryos compared with the brain tissues was higher by 13.9 %, while the level of unsaturation fatty acids in the liver, as compared with the brain was lower by 17.8 %. From the 22nd day of embryogenesis to the 1st day of postnatal development gradual increase in the content of unsaturated fatty acids in the liver was traced, while the level of their unsaturation in this period remained unchanged. A high content of unsaturated fatty acids was found in the liver of 1 day-old goslings, which is 15.8 % higher than the corresponding figure 22 day-old embryos. The first week of postnatal development was characterized by decrease in the content of unsaturated fatty acids in the liver by 25.0 %, and their level of unsaturation — by 21.62 %. The study results showed that one of the mechanisms of prooxidant- antioxidant balance support within the transition from of embryogenesis to postnatal development is to reduce the unsaturation of lipid fatty acids. This mechanism is realized in the brain of geese from hatching eggs of different quality. The support prooxidant-antioxidant balance in the liver by means of reducing the unsaturation of fatty acids is less effective and is mostly defined by fatty acid composition of lipids of geese hatching eggs

Correction of the aortic arch hypoplasia in newborn babies, suffering complete form of atrio-ventricular septal defect

Objective. Tactics of treatment and results of the hypoplasia of the aortic arch correction in newborn babies with complete form of atrio-ventricular septal defect were studied. Маterials and methods. During period from 2011 tо 2019 yrs in 21 patients correction of hypoplasia of aortic arch and atrio-ventricular septal defect were performed. The investigated group consisted of patients with a two-ventricular physiology. The patients, suffering imbalanced form of atrio-ventricular septal defect and with variants of hypoplasia in left parts of the heart, were excluded from the investigation. There were 9 (42.9%) boys and 12 (57.1%) girls. Average age of the patients have constituted (2.3 ± 1.1) mo (from 0.06 до 7.7 mo). Average body mass of the patients have constituted (3.8 ± 1.0) kg (from 2.0 до 5.9 kg). The aortic arch segment was considered a hypoplastic one if a Z-score (Standard Score - standard estimation) shift have constituted lesser than 2.0. Results. Hospital lethality have constituted 14.2%. Three newborn babies died: 2 - after first stage of correction, and 1 - after second stage of correction. All the patients, to whom a one-staged correction was done, have survived. The causes of lethality were not connected with method of the aortic arch reconstruction. While performance of echocardiography before discharge from the hospital the pressure gradient on place of the aortic arch plasty have constituted (13.6 ± 6.8) mm Hg at average. Average follow-up period have constituted (2.6 ± 2.1) yrs (from 2 mo tо 8.1 yr). In late follow-up period lethality was absent. In 2 (9.5%) patients in postoperative period reoperations on aortic arch and mitral valve were performed. Tracheal compression as well as the main bronchi compression, neurological complications in late follow-up period were absent. Conclusion. For the patients, suffering complete form of atrio-ventricular septal defect in conjunction with hypoplasia of aortic arch the staged correction constitutes a more favorable option, owing good immediate and late results. A staged approach in the treatment is indicated for newborn babies, suffering hypoplasia of distal aortic arch and competent atrio-venticular valves or with small regurgitation. Оne-stage correction is indicated in hypoplasia of aortic arch, pronounced regurgitation on common atrio-ventricular valve and pronounced heart failure

C-fos expression and cell proliferation in mice after exposure to nanosecond repetitively-pulsed X-rays

В статье указано Rostov, Vladimir V

Dissolved organic matter and microbial carbon of Protocalcic Chernozems of different land management

Water-extractable organic matter is the most active and mobile form of soil carbon. The other active fraction and extremely biolabile is the carbon constituent of microorganisms. Both of these fractions play an essential role in agrocenoses and in the global carbon cycle on our planet. The aim of the work was to estimate the carbon content of water-extractable organic matter as well as that of microbial origin in typical chernozems (Protocalcic Chernozems) of different land-use types. Protocalcic Chernozem samples taken from the fields of long-term experiments with different types of land use were investigated: a permanent bare fallow for 55 years (since 1964); conventional tillage – four-field crop rotation, first rotation; direct seeding – crop rotation similar to direct seeding, first rotation; a 21-year fallow (since 1998) after 34 years of bare fallow (since 1964). We determined the carbon content of water-extractable organic matter and the carbon content of microbial origin. In the studied series of variants, the proportion of carbon of water-extractable organic matter in the total amount of organic matter in the upper horizon (0–15 cm) was 0.69, 0.85, 1.01, and 0.98%, respectively, while that of carbon of microbial origin was 0.27, 0.55, 0.53, and 1.52%. It was noted that against the background of increasing the content of total organic carbon in direct seeding variant, compared with the traditional soil treatment, the microbial biomass in this variant does not increase. The fallow variant, unlike all other types of land use, is characterized by a higher proportion of microbial carbon, in contrast to the carbon of water-extractable organic matter

Menadione sodium bisulfite effect on growth performance and fatty acid profiles of geese muscle tissues

The specific effect of menadione sodium bisulfite (MSB, vicasol) on the content of specific fatty acids in skeletal muscle and muscular stomach of geese was established. MSB can stimulate the biosynthesis processes and catabolism of fatty acids depending on the period of the geese ontogenesis. Experimental use of MSB in skeletal muscle helps to increase the total content of unsaturated fatty acids (FA) primarily due to n-3 FAs. MSB increases the content of PUFA and SFA on the 35th day of ontogenesis, so the nutritional value of meat improves, and the resistance of myocyte membranes increases to oxidative damage. In the smooth muscle tissue of the goose stomach, the action of MSB revealed a higher content of UFA only on the 21st day of ontogenesis, due to PUFA, in particular, n-6 and MUFA. On the 28th day of ontogenesis, the content of PUFA increases due to n-3, with a decrease in the total content of UFA. At the end of the experiment, the UFA content decreases with increasing SFA. Reducton of the content of essential n-3, n-6, and UFA negatively affects the nutritional value of the product but increases the resistance of tissues to the active forms of oxygen. The use of MSB contributes to the overall increase of the average daily weight gain of geese from the 21st to the 28th day. The average body weight from the 21st to the 35th ontogenesis relative to the control group. We recommend using MSB at a dose of 0.7 mg/kg body weight for gosling feeding to increase the essential FA content in skeletal muscle tissue