215 research outputs found
The research of the maximum wind speed in Tomsk and calculations of dynamic load on antenna systems
The work is concerned with calculations and analysis of the maximum wind speed in Tomsk city. The data for analysis were taken from the TOR-station located in the north-eastern part of the city. The TOR-station sensors to measure a speed and a direction of wind are installed on the 10-meter meteorological mast. Wind is measured by M-63, which uses the standard approach and the program with one-minute averaging for wind gusts recording as well. According to the measured results in the research performed, the estimation of the dynamic and wind load on different types of antenna systems was performed. The work shows the calculations of wind load on ten types of antenna systems, distinguished by their different constructions and antenna areas. For implementation of calculations, we used methods developed in the Central Research and Development Institute of Building Constructions named after V.A. Kucherenko. The research results could be used for design engineering of the static antenna systems and mobile tracking systems for the distant objects
Disentangling methane and carbon dioxide sources and transport across the Russian Arctic from aircraft measurements
A more accurate characterization of the sources and sinks of methane (CH4) and carbon dioxide (CO2) in the vulnerable Arctic environment is required to better predict climate change. A large-scale aircraft campaign took place in September 2020 focusing on the Siberian Arctic coast. CH4 and CO2 were measured in situ during the campaign and form the core of this study. Measured ozone (O3) and carbon monoxide (CO) are used here as tracers. Median CH4 mixing ratios are fairly higher than the monthly mean hemispheric reference (Mauna Loa, Hawaii, US) with 1890–1969 ppb vs 1887 ppb respectively, while CO2 mixing ratios from all flights are lower (408.09–411.50 ppm vs 411.52 ppm). We also report on three case studies. Our analysis suggests that during the campaign the European part of Russia’s Arctic and Western Siberia were subject to long-range transport of polluted air masses, while the East was mainly under the influence of local emissions of greenhouse gases. The relative contributions of the main anthropogenic and natural sources of CH4 are simulated using the Lagrangian model FLEXPART in order to identify dominant sources in the boundary layer and in the free troposphere. In western terrestrial flights, air masses composition is influenced by emissions from wetlands and anthropogenic activities (waste management, fossil fuel industry and to a lesser extent the agricultural sector), while in the East, emissions are dominated by freshwaters, wetlands, and the oceans, with a likely contribution from anthropogenic sources related to fossil fuels. Our results highlight the importance of the contributions from freshwater and oceans emissions. Considering the large uncertainties associated to them, our study suggests that the emissions from these aquatic sources should receive more attention in Siberia.</p
The research of the maximum wind speed in Tomsk and calculations of dynamic load on antenna systems
The work is concerned with calculations and analysis of the maximum wind speed in Tomsk city. The data for analysis were taken from the TOR-station located in the north-eastern part of the city. The TOR-station sensors to measure a speed and a direction of wind are installed on the 10-meter meteorological mast. Wind is measured by M-63, which uses the standard approach and the program with one-minute averaging for wind gusts recording as well. According to the measured results in the research performed, the estimation of the dynamic and wind load on different types of antenna systems was performed. The work shows the calculations of wind load on ten types of antenna systems, distinguished by their different constructions and antenna areas. For implementation of calculations, we used methods developed in the Central Research and Development Institute of Building Constructions named after V.A. Kucherenko. The research results could be used for design engineering of the static antenna systems and mobile tracking systems for the distant objects
Periodical structure of bioaerosol concentration fields in the troposphere over the southern part of West Siberia
The properties of the bioaerosol concentration fields are also influenced by oscillatory processes in the atmosphere. The analysis of data on surface concentration of aerosols of total protein obtained in the vicinity of Novosibirsk presented in allowed us to find a correlation between the variations in the aerosol mass concentration and the total protein concentration in the surface atmospheric layer with its characteristic periodical synoptic processes. In this paper we present the results of wavelet and harmonic analysis of the experimental dataset on the concentration of aerosols of total protein and viable microorganisms in the troposphere over the southern part of West Siberia obtained during a 5-yr observation period (1999-2003). Copyright © 2004 by MAIK "Nauka /Interperiodica" (Russia)
Muscle Carnosine Is Associated with Cardiometabolic Risk Factors in Humans
Background Carnosine is a naturally present dipeptide abundant in skeletal muscle and an over-the counter food additive. Animal data suggest a role of carnosine supplementation in the prevention and treatment of obesity, insulin resistance, type 2 diabetes and cardiovascular disease but only limited human data exists. Methods and Results Samples of vastus lateralis muscle were obtained by needle biopsy. We measured muscle carnosine levels (high-performance liquid chromatography), % body fat (bioimpedance), abdominal subcutaneous and visceral adiposity (magnetic resonance imaging), insulin sensitivity (euglycaemic hyperinsulinemic clamp), resting energy expenditure (REE, indirect calorimetry), free-living ambulatory physical activity (accelerometers) and lipid profile in 36 sedentary non-vegetarian middle aged men (45±7 years) with varying degrees of adiposity and glucose tolerance. Muscle carnosine content was positively related to % body fat (r = 0.35, p = 0.04) and subcutaneous (r = 0.38, p = 0.02) but not visceral fat (r = 0.17, p = 0.33). Muscle carnosine content was inversely associated with insulin sensitivity (r = -0.44, p = 0.008), REE (r = -0.58, p<0.001) and HDL-cholesterol levels (r = -0.34, p = 0.048). Insulin sensitivity and physical activity were the best predictors of muscle carnosine content after adjustment for adiposity. Conclusion Our data shows that higher carnosine content in human skeletal muscle is positively associated with insulin resistance and fasting metabolic preference for glucose. Moreover, it is negatively associated with HDL-cholesterol and basal energy expenditure. Intervention studies targeting insulin resistance, metabolic and cardiovascular disease risk factors are necessary to evaluate its putative role in the prevention and management of type 2 diabetes and cardiovascular disease
Wildfire smoke in the Siberian Arctic in summer: source characterization and plume evolution from airborne measurements
We present airborne measurements of carbon dioxide (CO<sub>2</sub>), carbon monoxide (CO), ozone (O<sub>3</sub>), equivalent black carbon (EBC) and ultra fine particles over North-Eastern Siberia in July 2008 performed during the YAK-AEROSIB/POLARCAT experiment. During a "golden day" (11 July 2008) a number of biomass burning plumes were encountered with CO mixing ratio enhancements of up to 500 ppb relative to a background of 90 ppb. Number concentrations of aerosols in the size range 3.5–200 nm peaked at 4000 cm<sup>&minus;3</sup> and the EBC content reached 1.4 &mu;g m<sup>&minus;3</sup>. These high concentrations were caused by forest fires in the vicinity of the landing airport in Yakutsk where measurements in fresh smoke could be made during the descent. We estimate a combustion efficiency of 90 &plusmn; 3% based on CO and CO<sub>2</sub> measurements and a CO emission factor of 65.5 &plusmn; 10.8 g CO per kilogram of dry matter burned. This suggests a potential increase in the average northern hemispheric CO mixing ratio of 3.0–7.2 ppb per million hectares of Siberian forest burned. For BC, we estimate an emission factor of 0.52 &plusmn; 0.07 g BC kg<sup>&minus;1</sup>, comparable to values reported in the literature. The emission ratio of ultra-fine particles (3.5–200 nm) was 26 cm<sup>&minus;3</sup> (ppb CO)<sup>&minus;1</sup>, consistent with other airborne studies. <br><br> The transport of identified biomass burning plumes was investigated using the FLEXPART Lagrangian model. Based on sampling of wildfire plumes from the same source but with different atmospheric ages derived from FLEXPART, we estimate that the e-folding lifetimes of EBC and ultra fine particles (between 3.5 and 200 nm in size) against removal and growth processes are 5.1 and 5.5 days respectively, supporting lifetime estimates used in various modelling studies
Features of proinflammatory cytokine production in patients with allergic rhinitis combined with <i>Helicobacter pylori</i>-associated pathologies
Investigating a role for pro- and anti-inflammatory cytokines in immune and inflammatory response represents one of the most pressing topics in current immunology. There have been accumulated a great body of data regarding the cytokine status during inflammatory processes in gastrointestinal tract. However, many issues remain poorly elucidated. Moreover, most of the studies were mainly aimed at examining biopsy material cytokines collected from various parts of the gastrointestinal tract or gastric juice. Here we present the data on investigating the features of cytokine production in patients with allergic rhinitis combined with H. pylori-associated diseases of the upper gastrointestinal tract. A total of 225 patients aged 18 to 40 years (mean age 29.5±6.74 years) were examined, among which 43 patients suffered from allergic rhinitis, 66 patients had inflammatory diseases of the upper gastrointestinal tract (chronic gastritis/gastroduodenitis), and 69 patients — allergic rhinitis with concomitant inflammatory diseases of the upper gastrointestinal tract. Patients were stratified to various study groups depending on diagnosed allergic rhinitis and H. pylori infection. Serum IL-6 and IL-8 level and complete blood cell count were measured. Statistical significance for difference in parameter frequencies between independent groups was assessed by using Fisher's exact test or χ2 criteria. It was shown that serum IL-6 level in H. pylori-negative patients was within the reference interval with single spikes, whereas its production was markedly increased in patients with H. pylori infection regardless of allergic pathology. Frequency of subjects with elevated serum IL-8 level was comparable between groups of patients with gastrointestinal diseases, but significantly higher than that one in the control group. An interdependence between serum IL-8 level and white blood cell count was found, which is of interest for predicting development of the inflammatory process. Thus, the serum IL-8 level during the upper gastrointestinal tract inflammatory diseases was increased regardless of verified of H. pylori infection and allergic rhinitis, whereas increased IL-6 serum level was observed solely in H. pylori-positive patients
Physical characteristics of concentration fields of tropospheric bioaerosols in the South of Western Siberia
The State Research Center of Virology and Biotechnology "Vector" and the Institute of Optics SB RAS are performing systematic study of tropospheric bioaerosols in the South of Western Siberia. The work summarizes the results of analysis of some physical characteristics of the data array on bioaerosol concentration obtained with an airplane laboratory at the altitudes of 0.5, 1, 1.5, 2, 3, 4, 5.5 and 7 km. The flights were performed during the last 10 days of each month in 1999-2003. It was shown that the concentration of total protein aerosols obeyed the laws of continual statistics, and the concentration of culturable microorganism aerosols obeyed the laws of discrete statistics. The analysis of correlation coefficients and cross correlation of bioaerosol concentration fields was performed. Wavelet analysis of the data showed that variations of tropospheric bioaerosol concentration were mainly determined by typical seasonal processes with periods of 12, 6, 4 and 8-9 months. Seasonal variations cause approximately 80% of the total dispersion of variations of total protein concentration, and the amplitudes of variations of culturable microorganism concentration are small as compared with the constant component. Harmonic analysis of bioaerosol concentration fields was performed. Harmonics that are significant in wavelet spectra for all time series were taken for the approximation of the series. It was revealed that four-month periodicity was internal and was caused by a wave spreading from above with a vertical rate of about 4 km/month. © 2005 Elsevier Ltd. All rights reserved
Physical characteristics of concentration fields of tropospheric bioaerosols in the South of Western Siberia
The State Research Center of Virology and Biotechnology "Vector" and the Institute of Optics SB RAS are performing systematic study of tropospheric bioaerosols in the South of Western Siberia. The work summarizes the results of analysis of some physical characteristics of the data array on bioaerosol concentration obtained with an airplane laboratory at the altitudes of 0.5, 1, 1.5, 2, 3, 4, 5.5 and 7 km. The flights were performed during the last 10 days of each month in 1999-2003. It was shown that the concentration of total protein aerosols obeyed the laws of continual statistics, and the concentration of culturable microorganism aerosols obeyed the laws of discrete statistics. The analysis of correlation coefficients and cross correlation of bioaerosol concentration fields was performed. Wavelet analysis of the data showed that variations of tropospheric bioaerosol concentration were mainly determined by typical seasonal processes with periods of 12, 6, 4 and 8-9 months. Seasonal variations cause approximately 80% of the total dispersion of variations of total protein concentration, and the amplitudes of variations of culturable microorganism concentration are small as compared with the constant component. Harmonic analysis of bioaerosol concentration fields was performed. Harmonics that are significant in wavelet spectra for all time series were taken for the approximation of the series. It was revealed that four-month periodicity was internal and was caused by a wave spreading from above with a vertical rate of about 4 km/month. © 2005 Elsevier Ltd. All rights reserved
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