ABSTRACT
The spatial spin modulated structure (SSMS) of the cycloid type present in bulk BiFeO3 prevents the linear magnetoelectric effect. One way to influence this structure is to reduce the crystal size to the nanoscale. Various opinions are circulating in the literature about the effect of nanocrystal size on SSMS, and to investigate this issue, we used a number of methods, with zero-field NMR (ZF NMR) spectroscopy at the forefront. ZF NMR spectroscopy enables the direct observation of the distribution profile of local fields on iron atoms and defines the SSMS presence and its properties. We also examined the synthesized samples using XRD, TEM, and magnetometry. We conclude that SSMS persists as the nanocrystal size decreases to the cycloid period and less, becoming more harmonic. This is accompanied by the change of the anisotropy type from an "easy axis" to an "easy plane". Magnetic measurements show a significant increase in the saturation magnetization, remanent magnetization, coercivity, and exchange bias of nanocrystals with sizes close to the cycloid period, which is probably associated with incomplete spin compensation in the case of an incomplete cycloid period. Despite the fact that SSMS is retained in the samples with decreased size, the magnetic properties experience a sharp increase up to applicable values.
ABSTRACT
The dataset contains raw files related to the manuscript "The synergistic effect of a hybrid filler based on graphene nanoplates and multiwalled nanotubes for increasing the thermal conductivity of an epoxy composite" (Shalygina T.A. et al., 2021). The study presents the values of the heat capacity used to calculate the coefficients of thermal conductivity of epoxy composites by combining one-dimensional multiwalled nanotubes (MWCNTs) and two-dimensional graphene nanoplates (GNPs) in the role of a heat-conducting filler. To determine the heat capacity of materials with different concentrations of hybrid filler (GNP/MWCNT), the method of differential scanning calorimetry in the mode of the heat flux modulation was used. The analysis of the heat flux modulation samples is presented in raw and processed form. The materials scientists may apply the dataset to an in-depth study of the thermal conductivity formation mechanisms in composites doped with carbon-containing substances.
ABSTRACT
The C-2W experiment produces advanced beam-driven field reversed configuration (FRC) plasmas, which are sustained in steady state utilizing variable energy neutral beams (15-40 keV, total power up to 21 MW), advanced divertors, end bias electrodes, and an active plasma control system. Since heating, current drive, and refueling from neutral beam injection are essential to FRC sustainment, it is crucial to have accurate measurements of the beam power being injected into the plasma. A new tungsten wire calorimeter has been designed, built, calibrated on a test stand, and implemented to make the first direct measurements of the time-average injected beam power into C-2W. This paper outlines the design of the diagnostic, along with calibration methods and experimental results.
ABSTRACT
Reaction of nitrosochlorides of natural monoterpene hydrocarbons (+)-3-carene and (-)-α-pinene with L-amino acids and their methyl esters results in stereoselective formation of terpene-amino acids hybrids, which belong to the series of α-substituted amino oximes. The reaction with an excess of racemic DL-amino acids and their derivatives induces partial resolution of the amino acid components and formation of the diastereomeric mixtures of the terpene-amino acids hybrids, with diastereomeric excess varying from 0 to 100%.
Subject(s)
Amino Acids/chemistry , Monoterpenes/chemistry , Bicyclic Monoterpenes , Magnetic Resonance Spectroscopy , Stereoisomerism , Terpenes/chemistryABSTRACT
The article presents the results of the studies of cytotoxic effect of zearalenone and T-2 toxin on sperm of horses and bulls during incubation and after thawing according to the technology of sperm obtaining and cryopreservation in Kharkov. We first have shown in vitro toxic effects of different concentrations of zearalenone and T-2 toxin (from 0.5 to 0.01 mM) on the membrane stability, as well as quantitative and qualitative indicators of semen in stallions and bulls before and after freezing and thawing. It has been found that the biological activity of the native sperm in 1 h after addition of 0.5 mM zearalenone is not changed, and after thawing is reduced by 19.4 %, or 0.69 ball (P < 0.01) compared to control without toxin. T-2 toxin at a concentration of 0.5 mM reduced the activity of the native sperm after an hour of incubation by 0.59 ball (P < 0.01) and decreased it after thawing decreased by 60.28 %, or 2.14 ball (P < 0.001). 1 h of incubation with zearalenone at concentration of 0.25 mM did not affect the activity of the native sperm, but the activity after freezethaw deteriorated by 12.2 %, or 0.41 ball (P < 0.05). T-2 toxin at a concentration of 0.25 mM reduced activity of native sperm after 1 h exposure by 0.46 ball (P < 0.05), and after thawing spermatozoa degrade it by 1.77 ball (P < 0.001) compared to control without toxins. In our study, the lowest concentration giving a significant decrease in sperm parameters was 0.01 mM. The negative impact of zearalenone in such a dose on the native sperm was absent, and sperm after thawing only slightly reduced activity and perezhivayemost by 0.09 points and 0.27 hours, respectively. The simultaneous addition of zearalenone and T-2 toxin at the same dose of 0.01 mM resulted in a decrease in biological perezhivayemost and absolute indicator of native sperm perezhivayemost by 0.36 points and 0.64 hours (P < 0.05), respectively.
Subject(s)
Cryopreservation , Cytotoxins/pharmacology , Spermatozoa , T-2 Toxin/pharmacology , Zearalenone/pharmacokinetics , Animals , Cattle , Dose-Response Relationship, Drug , Horses , Male , Spermatozoa/metabolism , Spermatozoa/ultrastructure , Time FactorsABSTRACT
The possible presence of the physiological relationship of erythrocyte antigens of the A, C, D, K alleles of the blood group systems in the examined horses of the Ukrainian selection with the spermogram major parameters has been demonstrated. It has been found that when investigating ad/bcm and dg/cgm alleles of the blood group system D in the stallions, there was the physiological tendency of the decrease in the semen activity on average less than 5 points; at the presence of ad/cgm, ad/d, ad/ de, ad/dk, bcm/d, bcm/de, bcm/dg bcm/dk cegm/cgm, cegm/d, cegm/dg, cegm/dk cgm/ceg, cgm/cgm, cgm/dg, cgm/dk de/ cgm, de/dk dg/di, dk/d, dk/de, dk/dk alleles the spermogram of the average quality with the activity of the semen on average from 5 to 7 points was obtained; at the presence of bcm/cgm, dg/dk, de/d, egm/d, cgm/de alleles high parameters of semen activity, more than 7 points, were received. The tendency of the increase in the semen concentration was revealed in the examined stallions having a/- allele of the blood group C. The possible decrease in the semen concentration in the stallions having a/-allele of the blood group K was shown. The alleles of the blood group system D had the highest statistical impact on the volume of the ejaculate, the activity, concentration and the number of pathological forms of semen, the correlation coefficient was 0,36; 0,31; 0, 43 and 0,27, respectively. At the same time it has been found out that the alleles of the blood group systems A,C and K had the coefficient of correlation with the examined parameters of the semen at the level of not more than 0,07.
Subject(s)
Alleles , Blood Group Antigens/classification , Erythrocytes/chemistry , Semen Analysis/statistics & numerical data , Spermatozoa/physiology , Animals , Blood Group Antigens/genetics , Blood Group Antigens/metabolism , Cell Count , Gene Expression , Horses , Male , Regression Analysis , Sperm Count , Sperm Motility/physiology , Spermatozoa/cytologyABSTRACT
AIM: to analyze and summarize the data of the DIREG-2 study of the nonalcoholic fatty liver disease (NAFLD) register in Rostov-on-Don versus those in Russia. MATERIAL AND METHODS: The prospective disease registry study encompasses an epidemiologic, observational, cross-sectional, multicenter study estimating the prevalence of NAFLD in outpatients in Rostov-on-Don. A total of 3200 patients participated in this study. The investigators were 65 outpatient physicians. Epidemiological data were obtained during two patient visits to the research centers. RESULTS: The key result obtained from this study was the significantly higher prevalence of NAFLD in Rostov-on-Don than that in the general population (40.4 and 37.3%). In addition to the higher prevalence of NAFLD, there was also a higher spread of risk factors (RFs), such as abdominal obesity, female age of 45-55 years, and hyperlipidemia. CONCLUSION: The prevalence of NAFLD in the outpatients of Rostov-on-Don was 3.1% greater than that in Russia; this might be due to the significantly higher spread of some RFs (abdominal obesity, female age of 45-55 years, hyperlipidemia). The findings are undoubtedly necessary for the elaboration of measures for the primary and secondary prevention of NAFLD in Rostov-on-Don.
Subject(s)
Non-alcoholic Fatty Liver Disease , Quality of Life , Aged , Cross-Sectional Studies , Disease Progression , Female , Humans , Male , Middle Aged , Non-alcoholic Fatty Liver Disease/diagnosis , Non-alcoholic Fatty Liver Disease/epidemiology , Non-alcoholic Fatty Liver Disease/psychology , Outpatients/statistics & numerical data , Prevalence , Prognosis , Risk Factors , Russia/epidemiologyABSTRACT
In the present paper, the optical density of dispersions of randomly oriented multilayer graphene nanoplatelets (GNPs) was estimated. Calculated and experimental data were compared for aqueous GNP dispersions stabilized with various surfactants. It was shown that the sonication of an expanded graphite compound (EGC) in aqueous surfactant solutions leads to the transformation of EGC worm-like particles into weak GNP aggregates which are able to pass into solution upon dilution and agitation of the system. They may be filtered and washed out of surfactants. The concentrated GNP dispersions containing these weak aggregates can be used to synthesize different graphene-based nanostructures and obtain novel composite materials.
ABSTRACT
We studied the effects of regular long-term exposure to industrial nanomaterial based on multiwalled carbon nanotubules on the digestive system of mice. Nanomaterial in a concentration of 30 mg/kg was administered with drinking water over 30 days. Tissue specimens from the small intestine and liver were studied by light and electron microscopy. Multiwalled carbon nanotubules caused multiple necrotic foci in the small intestine and mixed parenchymatous degeneration in the liver. These findings suggested that multiwalled carbon nanotubules entering the digestive tract damaged intestinal villi, presumably via mechanical damage to enterocytes. It seems that multiwalled carbon nanotubules could cause degeneration indirectly, by triggering inflammatory reactions and ROS generation.
Subject(s)
Intestinal Mucosa/pathology , Intestine, Small/pathology , Nanotubes, Carbon/toxicity , Animals , Cell Shape/drug effects , Drug Evaluation, Preclinical , Enterocytes/drug effects , Enterocytes/physiology , Hepatocytes/drug effects , Intestinal Mucosa/drug effects , Intestine, Small/drug effects , Kupffer Cells/drug effects , Liver/drug effects , Liver/pathology , Mice, Inbred C57BL , Mice, Inbred DBA , Necrosis/chemically inducedABSTRACT
This study was carried out in a factory producing multiwalled carbon nanotubes (MWCNTs) by the catalytic chemical vapor deposition method in a pyrolysis reactor. Air samples of the personal breathing areas were collected simultaneously on mixed cellulose ester filters, for analysis by transmission electron microscopy (TEM), and on high-purity quartz filters for thermal-optical analysis of elemental carbon (EC). It is found that the production of MWCNTs is accompanied by the release of the MWCNT structures in the air of different working zones. The concentration of respirable aerosol in the personal breathing areas, averaged over an 8-hour period, ranges from 0.54 to 6.11 µg/m3 based on EC. Airborne MWCNTs were found in the form of agglomerates that range in size from about 1 to 10 µm. These data are consistent with measurements in different plants by two other international groups (from the United States and Sweden) using similar methodology (TEM in combination with EC analysis). In the absence of convincing data on the potential health risks of MWCNTs, and following the principle of reasonable precautions, preventive measures should be taken to minimize exposure to these materials.
ABSTRACT
We tested possibility of the use of apelin-12 as a biomarker of chronic heart failure (CHF). The study comprised 108 patients with I-IV functional class CHF of various etiology (ischemic heart disease, dilation cardiomyopathy) and 40 healthy volunteers. Blood samples were taken at hospital admission before prescription of pharmacological therapy. In all patients we carried out echocardiography with calculation of end-diastolic and end-systolic volumes (EDV, ESV) and ejection fraction (EF). Blood plasma apelin-12 concentration was compared with CHF market NT-proBNP. Mean apelin-12 concentrations were 0.86+/-0.22 hg/ml in healthy volunteers and 0.8+/-0.35, 0.81+/-0.29, 0.68+/-0.38, 0.82+/-0.35 hg/ml in patients with CHF classes I, II, III, IV, respectively. There was no significant differences between appelin-12 concentrations in various classes of CHF. No correlations were found between apelin-12 and EF, EDV, ESV, sex, age, smoking, body mass index, and NT-proBNP level. Concentration of NT pro-BNP level correlated with CHF severity. Thus apelin-12 did not show itself as reliable biomarker of CHF.
ABSTRACT
Measurements of the flux of fusion products from high temperature plasmas provide valuable insights into the ion energy distribution, as the fusion reaction rate is a very sensitive function of ion energy. In C-2, where field reversed configuration plasmas are formed by the collision of two compact toroids and partially sustained by high power neutral beam injection [M. Binderbauer et al., Phys. Rev. Lett. 105, 045003 (2010); M. Tuszewski et al., Phys. Rev. Lett. 108, 255008 (2012)], measurements of DD fusion neutron flux are used to diagnose ion temperature and study fast ion confinement and dynamics. In this paper, we will describe the development of a new 3 MeV proton detector that will complement existing neutron detectors. The detector is a large area (50 cm(2)), partially depleted, ion implanted silicon diode operated in a pulse counting regime. While the scintillator-based neutron detectors allow for high time resolution measurements (â¼100 kHz), they have no spatial or energy resolution. The proton detector will provide 10 cm spatial resolution, allowing us to determine if the axial distribution of fast ions is consistent with classical fast ion theory or whether anomalous scattering mechanisms are active. We will describe in detail the diagnostic design and present initial data from a neutral beam test chamber.
ABSTRACT
Engineered nanoparticles (ENPs) are now being used in many sectors of industry; however, the impact of ENPs on the environment still requires further study, since their use, recycling, and accidental spill can result in the accumulation of nanoparticles in the atmosphere, soil, and water. Plants are an integral part of ecosystems; hence their interaction with ENPs is inevitable. It is important to understand the consequences of this interaction and assess its potential effects. The present research is focused on studying the effects of the industrial material Taunit, containing multi-walled carbon nanotubes (MWNTs), on plants, and testing of its ability to penetrate into plant cells and tissues. Taunit has been found to stimulate the growth of roots and stems and cause an increase in peroxidase activity inOnobrychis arenariaseedlings. Peroxidase activity increases with decreasing concentration of Taunit from 1,000 to 100 mg/l. MWNTs from Taunit were detected in the cells and tissues of seedling roots and leaves, implying the ability of MWNTs to penetrate into roots and accumulate there, as well as their ability to be transported into seedling leaves. Thus, the changes in the physiological parameters of plants are associated not only with MWNT adsorption on the root surface, as previously believed, but also with their penetration, uptake and accumulation in the plant cells and tissues.
ABSTRACT
Residues of persistent organic pollutants (POPs) were analysed in 70 selected food items from Northwest Russia in 1998-2002. Levels of PCBs ranged from 0.2 to 16ng/g wet weight (ww) in dairy products and fats, 0.2 to 23ng/g ww in meat products, 0.5 to 16ng/g ww in eggs and 0.3 to 30ng/g ww in fish. High levels of DDT (16ng/g ww) were found in locally produced butter from Kola Peninsula, in pork fat from Arkhangels region (10 to 130ng/g ww) and in some fish samples from White Sea and Kargopol region (17 and 30ng/g ww). Findings of low DDE/DDT ratios in many of the studied food items indicated recent contamination to DDTs. Mean levels of sum TEQs(WHO1998) of dioxin-like mono-ortho PCBs: PCBs 105, 118, 156 and 157 (∑mo-PCBs-TEQs(WHO1998)) were highest in dairy products, chicken eggs and fish, with levels of 0.292, 0.245 and 0.254pg/g ww, respectively. The estimated daily intake (EDI) for ∑mo-PCBs-TEQs(WHO1998) was 0.74pg/kgbw/day and in the same range as in Sweden and Denmark. Fish, dairy products, eggs and meat were the main contributors to the EDI of ∑mo-PCBs-TEQs(WHO1998). The EDIs of DDTs, HCHs and HCB were several times higher than in Sweden and Denmark. Consumption of meat and poultry were important sources for intake of DDTs and HCHs, respectively. Contamination of animal feed and agricultural practice were assumed the most important causes for the results in the present study. However, increased control on maximum residue levels in food and feed may have resulted in large changes on levels and patterns of POPs in food in the studied areas.
Subject(s)
Environmental Exposure/analysis , Environmental Monitoring , Food Contamination/analysis , Organic Chemicals/analysis , Soil Pollutants/analysis , DDT/analysis , Dairy Products/analysis , Dichlorodiphenyl Dichloroethylene/analysis , Diet , Eggs/analysis , Environmental Exposure/statistics & numerical data , Environmental Pollution/statistics & numerical data , Food Analysis , Food Contamination/statistics & numerical data , Humans , Meat/analysis , Polychlorinated Biphenyls/analysis , RussiaSubject(s)
Betula/metabolism , Moths/physiology , Plant Leaves/metabolism , Terpenes/metabolism , Animals , Female , MaleABSTRACT
This study presents for the first time temporal changes of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in Russian human breast milk samples. Concentrations of OCPs and PCBs in samples from three locations in the North West of Russia in 2000-2002 (n=42), were compared to corresponding levels measured in 1993-1996 (n=58). In addition brominated flame retardants (BFRs), consisting of polybrominated diphenylethers (PBDEs) (including BDE-209) and hexabromocyclododecane (HBCD) were analysed in samples from 2000-2002 (n=37). The present levels of SigmaDDTs and SigmaHCHs were 5 and 10 times higher than corresponding levels in the neighbouring country Norway. Median concentrations of SigmaHCHs (196 microg/kg lw), SigmaCHBs (19.7 microg/kg lw) and SigmaPCBs(16) (316 microg/kg lw) were highest in Murmansk. The percentage of p,p'-DDT to SigmaDDTs and ratio DDE/DDT suggest possible ongoing use of DDT in Russia. Levels of PBDE were low and dominated by the congeners BDE-47 and BDE-153. The deca brominated BDE-209 was detected in all analysed samples (median concentration 0.19 microg/kg lipid). Levels of SigmaOCPs and SigmaPCBs decreased 56 and 30% in Murmansk and 36 and 43% in Arkhangelsk during the study period. The decline of SigmaOCPs was significant at both locations (p<0.05-p<0.0001). For SigmaPCBs, the decreasing trend was only significant in Arkhangelsk (p<0.0001). In addition, a decline of Sigmatotal TEQs (SigmaTEQs of PCDDs/PCDFs, non-ortho- and mono-ortho PCBs) was observed in Murmansk and Arkhangelsk during the study period. The exposure of infants by PCDDs/PCDFs and dioxin-like PCBs is still exceeding the daily tolerable intake (TDI) in North West Russia. However, the concentrations of PCDDs/PCDFs and dioxin-like PCBs seem to decline very rapidly.
Subject(s)
Environmental Pollutants/metabolism , Maternal Exposure , Milk, Human/chemistry , Adolescent , Adult , Benzofurans/metabolism , Body Burden , Dibenzofurans, Polychlorinated , Environmental Monitoring , Female , Flame Retardants/metabolism , Humans , Hydrocarbons, Brominated/metabolism , Hydrocarbons, Chlorinated/metabolism , Infant, Newborn , Male , Pesticides/metabolism , Phenyl Ethers/metabolism , Polybrominated Biphenyls/metabolism , Polychlorinated Dibenzodioxins/analogs & derivatives , Polychlorinated Dibenzodioxins/metabolism , RussiaABSTRACT
65 patients with a mild craniocereberal trauma have been observed. Medical examination included among general clinical methods the following methods: KT (MRT) of the brain, oculist examination including the observation of eye fundus. For objectification of a patient' complaints the authors used orientation and Galvestona's amnesia tests, feeling scale (psychological test), the table to determine the level of memory. Tests have been carried out on the first, tenth and thirty day of the treatment. Patients of the first group received in a complex treatment -pramistar, patients of the second group - piracetam. Patients of both groups noted considerable improvement during a complex treatment (disappearance of headache, dizziness and nausea) and at the same time patients receiving pramistar had better restoration of orientation and feeling. Pramistar was also more effective in patients with amnesia.
Subject(s)
Brain Concussion/drug therapy , Nootropic Agents/therapeutic use , Piracetam/therapeutic use , Pyrrolidines/therapeutic use , Adolescent , Adult , Attention/drug effects , Brain Concussion/psychology , Drug Therapy, Combination , Humans , Memory/drug effects , Middle Aged , Neuropsychological Tests , Nootropic Agents/administration & dosage , Nootropic Agents/adverse effects , Piracetam/administration & dosage , Piracetam/adverse effects , Pyrrolidines/administration & dosage , Pyrrolidines/adverse effects , Treatment OutcomeSubject(s)
Acclimatization/physiology , Light , Pituitary Gland/physiology , Thyroid Gland/physiology , Adolescent , Child , Female , Humans , Male , Pituitary Hormones/blood , Seasons , Thyroid Hormones/bloodSubject(s)
Digestive System Diseases/complications , Dyspepsia/drug therapy , Histamine H2 Antagonists/therapeutic use , Ranitidine/therapeutic use , Adolescent , Adult , Aged , Dyspepsia/diagnosis , Dyspepsia/etiology , Female , Histamine H2 Antagonists/administration & dosage , Histamine H2 Antagonists/adverse effects , Humans , Male , Middle Aged , Ranitidine/administration & dosage , Ranitidine/adverse effects , Severity of Illness Index , Treatment OutcomeABSTRACT
The hormonal level dynamics of hypophysis, thyroid gland and sex steroids was analyzed in respect to the puberty. Concentrations of gonadotropins and sex streroids were increased whereas concentrations of thyroid hormones was decreased. The amplitude of hypophysis and thyroid hormones were narrowed whereas the range of sex steroids was extended during the puberty. In early stages of puberty, the interhormonal correlations existed on some levels (hypophysis or peripheral gland), but in late stage the intersystem and polyhormonal relations were formed. Thyroid hormones play a leading role in sexual maturity regulation. The sexual maturity is prolonged, the variance of sexual stages being quite wide. The range of gonadotropin shifted to the left side in comparison with children in moderate latitudes.