Dependence of vestibular reactions on frequency of action of sign-variable accelerations

It was revealed that during the tests with continuous action of sign variable Coriolis acceleration the development of kinetosis was proportionate to the time of head inclinations in the range of 1 to 4 seconds while illusions of rocking in sagittal plane was more expressed in fast inclinations. The obtained data provided the evidence of sufficient dependence of vestibulovegetative and vestibulosensory reactions on the period of repetition of sign variable Coriolis acceleration

Fluvial carbon dioxide emission from the Lena River basin during the spring flood

Greenhouse gas (GHG) emission from inland waters of permafrost-affected regions is one of the key factors of circumpolar aquatic ecosystem response to climate warming and permafrost thaw. Riverine systems of central and eastern Siberia contribute a significant part of the water and carbon (C) export to the Arctic Ocean, yet their C exchange with the atmosphere remains poorly known due to lack of in situ GHG concentration and emission estimates. Here we present the results of continuous in situ pCO2 measurements over a 2600 km transect of the Lena River main stem and lower reaches of 20 major tributaries (together representing a watershed area of 1 661 000 km2, 66 % of the Lena's basin), conducted at the peak of the spring flood. The pCO2 in the Lena (range 400-1400 μatm) and tributaries (range 400-1600 μatm) remained generally stable (within ca. 20 %) over the night-day period and across the river channels. The pCO2 in tributaries increased northward with mean annual temperature decrease and permafrost increase; this change was positively correlated with C stock in soil, the proportion of deciduous needleleaf forest, and the riparian vegetation. Based on gas transfer coefficients obtained from rivers of the Siberian permafrost zone (kCombining double low line4.46 md-1), we calculated CO2 emission for the main stem and tributaries. Typical fluxes ranged from 1 to 2 gCm-2d-1 (>99 % CO2, <1 % CH4), which is comparable with CO2 emission measured in the Kolyma, Yukon, and Mackenzie rivers and permafrost-affected rivers in western Siberia. The areal C emissions from lotic waters of the Lena watershed were quantified by taking into account the total area of permanent and seasonal water of the Lena basin (28 000 km2 ). Assuming 6 months of the year to be an open water period with no emission under ice, the annual C emission from the whole Lena basin is estimated as 8.3±2.5 TgCyr-1, which is comparable to the DOC and dissolved inorganic carbon (DIC) lateral export to the Arctic Ocean

Measurement of the 236^{236}U fission cross section and angular distributions of fragments from fission of 235^{235}U and 236^{236}U in the neutron energy range of 0.3-500 MeV

The $^{236}$U fission cross section and the angular distributions of fragments from fission of $^{235}$U and $^{236}$U were measured for incident neutron energies from 0.3 MeV to 500 MeV on the time-of-flight spectrometer of the neutron complex GNEIS at the NRC "Kurchatov Institute" -- PNPI. Fission fragments were registered using position-sensitive low-pressure multiwire counters. In the neutron energy range above 20 MeV, the angular distributions of $^{236}$U fission fragments were measured for the first time. The fission cross section of $^{236}$U$(n,f)$ was measured relative to the fission cross section of $^{235}$U$(n,f)$, which is an accepted international standard. The obtained data are compared with the results of other experimental works. Theoretical calculations of the fission cross section and the anisotropy of angular distribution of fission fragments for the $^{236}$U$(n,f)$ reaction performed within the framework of our approach are presented and discussed.Comment: 21 pages, 22 figures, revised version accepted for publication in Phys. Rev.

The relevance of the contemporary landscape-ecological and biogeochemical studies of the Ob floodplain

We have systematized and summarized the results of the Ob River floodplain studies and have shown that the flood and the floodplain influence all the territory of Western Siberia due to the processes happening there. The floodplain at different times was the object of interest of many scientists, but the total level of study of the Ob and the associated ground and the lake network water resources and quality can be generally assessed as low. The waters of the Ob middle course are quite polluted according to bacteria content. It is possible that a significant part oforganic and biogenic substances, microorganisms and some microelements come into the Ob floodplain waters from anthropogenic and natural sources distributed in the watersheds area. The soils of the Ob Riverfloodplain can be considered to be clean andfree ofany chemical pollution. In these soils, the amount of trace elements is small. To study the floodplain changes after a flood the methods of landscape ecology are used, such as the collection and analysis of stock and descriptive materials, literature and maps; the preparation of a series of component and general landscape maps. Nowadays a complex research of the Ob River and the adjacent surface waters is relevant

Ictal and interictal MEG in pediatric patients with tuberous sclerosis and drug resistant epilepsy

Purpose: Drug resistant epilepsy (DRE) is common in patients with tuberous sclerosis (TS). Interictal MEG has been shown as a valuable instrument in the presurgical workup. The goal of our study was to evaluate the role of ictal MEG in epileptogenic tuber selection, especially in patients with multiple irritative zones. Methods: The clinical and MEG data of 23 patients with TS and DRE from two medical/research centers were reviewed. Seven pediatric patients, who had seizures during MEG recording and underwent resection or disconnection surgery, were included into the study. Cortical sources of ictal and interictal epileptiform MEG discharges were compared with epileptogenic zone location in six patients with favorable surgery outcome. Results: In patients who improved substantially after surgery all resected and several other tubers demonstrated epileptiform activity on interictal MEG. Ictal MEG provided crucial information about lobar location of the seizure onset zone (SOZ) in two cases, and in the other four it confirmed the SOZ location derived from the interictal data. In one case, ictal MEG findings were unreliable. In one patient, who did not benefit from surgical treatment, the resected tubers did not overlap with interictal and ictal MEG sources. Conclusion: The combination of interictal and ictal MEG is a valuable tool for identification of the epileptogenic tuber/tubers in presurgical work-up in patients with TS.Peer reviewe

New opportunities for the correction of non-alcoholic fatty liver disease in men with type 2 diabetes mellitus and hypogonadism

Background: The common pathogenetic relations of type 2 diabetes mellitus (T2DM), testosterone (T) deficiency and non-alcoholic fatty liver disease (NAFLD) have indicated a new direction in the study of their mutual influence. It was found that NAFLD is more pronounced in men with T2DM and hypogonadism than in eugonadal patients and associated with hyperinsulinemia, insulin resistance, impaired lipid metabolism and adipose tissue dysfunction. However, the effects of testosterone replacement therapy (TRT) on the severity of NAFLD in men with hypogonadism have not been studied.Aims: To study the effect of TRT on the severity of NAFLD in men with T2DM and hypogonadism.MATERIALS AND METHODS: Anthropometric data, biochemical parameters (alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyltranspeptidase (GGTP), glucose, immunoreactive insulin, HOMA index, glycosylated hemoglobin, lipidogram), ELISA analysis (total T, LH, sex hormone binding globulin, resistin, adiponectin, leptin), as well as magnetic resonance imaging with determination of the liver fat fraction were examined.Results: The study included 60 men with T2DM and hypogonadism (mean age 54 [49; 57] years), who were randomized into 2 groups: 1 (n=30) - patients who received 1% transdermal T gel (50 mg/day) in addition to standard hypoglycemictherapy; 2 (n=30) - patients who received standard hypoglycemic therapy. The follow-up period was 6 months. T therapy was associated with a decrease in liver enzyme levels: AST by 31%, ALT by 21%, and GGTP by 15.9% (p&lt;0.05) and the hepatic fat fraction by 1.7 times, which reflect the regress of liver inflammation, and, consequently, a decrease in the severity of NAFLD. Moreover, TRT has improved the function of adipose tissue - reduced the concentration of leptin by 1.4 times and resistin by 1.5 times, which was accompanied by an increase in adiponectin level by 1.3 times (p&lt;0.01). The use of TRT was associated with decrease in the severity of visceral obesity, hyperinsulinemia by 1.5 times, an insulin resistance index HOMA by 2.2 times, fasting glycaemia and HbA1c levels, despite constant hypoglycemic therapy. Statistically significant decrease in the levels of total cholesterol and triglycerides was observed in men receiving TRT. Thus, a decrease in adipose tissue dysfunction and insulin resistance in men receiving TRT can be considered as a pathogenetic mechanism responsible for improving liver function and reducing the severity of NAFLD.Conclusions: TRT in men with T2DM and hypogonadism is accompanied by regress of inflammatory activity in liver and intensity of hepatocytes steatosis, reflected by decrease in liver enzymes levels and liver fat fraction

Measurement of the front-end dead-time of the LHCb muon detector and evaluation of its contribution to the muon detection inefficiency

A method is described which allows to deduce the dead-time of the front-end electronics of the LHCb muon detector from a series of measurements performed at different luminosities at a bunch-crossing rate of 20 MHz. The measured values of the dead-time range from 70 ns to 100 ns. These results allow to estimate the performance of the muon detector at the future bunch-crossing rate of 40 MHz and at higher luminosity