14 research outputs found
The first data on methane concentrations in degassing griffins of Lake Baskunchak
For the first time, the distribution of methane in the brine and bottom sediments of the Ulan-Blag stream (tributary of Lake Baskunchak), fed by underground degassing springs, as well as directly in Baskunchak Lake at a distance from underground sources. The composition of the main ions in brine, acid-base and redox conditions in bottom sediments have been established. The brine mineralization in Baskunchak Lake is 312 g/dm3, which is 2.1 times higher than the mineralization of the Ulan-Blag stream. The chemical composition of the brine of both stations is classified as chloride type, sodium cationic composition. The concentration of methane in the brine of the studied underground degassing sources in the ravine stream of the Ulan-Blag reaches high values (up to 215 µl/dm3), exceeding by 1–2 orders of magnitude its concentration in the brine of Lake Baskunchak. The low concentrations of methane in the brine of the lake are probably due to its insignificant flow from the bottom sediments into the water due to the presence of a salt crust that prevents gas emission, as well as due to its small concentrations in the upper layers of sediments
Impulsive Fermi magnon-phonon resonance in antiferromagnetic
Understanding spin-lattice interactions in antiferromagnets is one of the
most fundamental issues at the core of the recently emerging and booming fields
of antiferromagnetic spintronics and magnonics. Recently, coherent nonlinear
spin-lattice coupling was discovered in an antiferromagnet which opened the
possibility to control the nonlinear coupling strength and thus showing a novel
pathway to coherently control magnon-phonon dynamics. Here, utilizing intense
narrow band terahertz (THz) pulses and tunable magnetic fields up to 7 T, we
experimentally realize the conditions of the Fermi magnon-phonon resonance in
antiferromagnetic . These conditions imply that both the spin and the
lattice anharmonicities harvest energy transfer between the subsystems, if the
magnon eigenfrequency is twice lower than the frequency of the phonon
. Performing THz pump-infrared probe spectroscopy in conjunction
with simulations, we explore the coupled magnon-phonon dynamics in the vicinity
of the Fermi-resonance and reveal the corresponding fingerprints of an
impulsive THz-induced response. This study focuses on the role of nonlinearity
in spin-lattice interactions, providing insights into the control of coherent
magnon-phonon energy exchange
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Label-free characterization of white blood cells using fluorescence lifetime imaging and flow-cytometry: molecular heterogeneity and erythrophagocytosis [Invited]
Article reporting the results of blood cell characterization using label-free fluorescence imaging techniques and flow-cytometry. Autofluorescence parameters of different cell types – white blood cells, red blood cells, erythrophagocytic cells – are assessed and analyzed in terms of molecular heterogeneity and possibilities of differentiation between different cell types in vitro and in vivo
Особенности ДНК-идентификации потожировых следов на кожных покровах трупов
The paper presents the results of a pilot molecular genetic study of sweat and oil residue left by the fingertips and hand palms of male volunteers (donors) on various regions of the skin surface of dead bodies (recipients) of both sexes. In cases of contact with female recipients donor-specific allele combinations were obtained for only 11.6% of autosomal loci and 12.9% of Y-chromosomal loci. Donor-specific traits were absent in 68.4% of autosomal loci and 87.1% of Y-chromosomal loci. In cases of contact with male recipients the full genetic profile was obtained for 18.6% of autosomal loci, and 64.2% of loci showed a lack of donor-specific alleles. Meanwhile, allelic combinations specific to female recipients were encountered in 40.5% of autosomal loci, and to male recipients – in 34.2% of autosomal loci. Results demonstrate poor adhesion of sweat and oil compounds from donors’ hands to the corpses’ skin, probably due to significant temperature differences between contact surfaces. Представлены результаты экспериментального молекулярно-генетического исследования следов потожирового вещества, оставленного подушечками пальцев рук и ладонями добровольцев (доноров) мужского пола на кожных покровах различных частей тел трупов (реципиентов) обоего пола. Аллельные комбинации, свойственные донорам, при контакте с реципиентами женского пола получены только для 11,6 % аутосомных локусов и 12,9 % локусов Y-хромосомы. В 68,4 % аутосомных и 87,1 % локусов Y-хромосомы отсутствовали генетические признаки, присущие донорам. В случае контакта доноров с реципиентами мужского пола полный генетический профиль получен для 18,6 % аутосомных локусов, а в 64,2 % отсутствовали свойственные донорам аллели. При этом аллельные комбинации, свойственные реципиентам женского пола, встречались в 40,5 %, а реципиентам мужского пола – в 34,2 % аутосомных локусов. Полученные результаты могут свидетельствовать о слабой адгезии потожирового вещества доноров на кожных покровах трупов, вероятно, из-за высокой разницы температур контактирующих поверхностей
Polarimetric Properties of Event Horizon Telescope Targets from ALMA
We present the results from a full polarization study carried out with the Atacama Large Millimeter/submillimeter Array (ALMA) during the first Very Long Baseline Interferometry (VLBI) campaign, which was conducted in 2017 April in the λ3 mm and λ1.3 mm bands, in concert with the Global mm-VLBI Array (GMVA) and the Event Horizon Telescope (EHT), respectively. We determine the polarization and Faraday properties of all VLBI targets, including Sgr A*, M87, and a dozen radio-loud active galactic nuclei (AGNs), in the two bands at several epochs in a time window of 10 days. We detect high linear polarization fractions (2%–15%) and large rotation measures (RM > 103.3–105.5 rad m−2), confirming the trends of previous AGN studies at millimeter wavelengths. We find that blazars are more strongly polarized than other AGNs in the sample, while exhibiting (on average) order-of-magnitude lower RM values, consistent with the AGN viewing angle unification scheme. For Sgr A* we report a mean RM of (−4.2 ± 0.3) × 105 rad m−2 at 1.3 mm, consistent with measurements over the past decade and, for the first time, an RM of (–2.1 ± 0.1) × 105 rad m−2 at 3 mm, suggesting that about half of the Faraday rotation at 1.3 mm may occur between the 3 mm photosphere and the 1.3 mm source. We also report the first unambiguous measurement of RM toward the M87 nucleus at millimeter wavelengths, which undergoes significant changes in magnitude and sign reversals on a one year timescale, spanning the range from −1.2 to 0.3 × 105 rad m−2 at 3 mm and −4.1 to 1.5 × 105 rad m−2 at 1.3 mm. Given this time variability, we argue that, unlike the case of Sgr A*, the RM in M87 does not provide an accurate estimate of the mass accretion rate onto the black hole. We put forward a two-component model, comprised of a variable compact region and a static extended region, that can simultaneously explain the polarimetric properties observed by both the EHT (on horizon scales) and ALMA (which observes the combined emission from both components). These measurements provide critical constraints for the calibration, analysis, and interpretation of simultaneously obtained VLBI data with the EHT and GMVA
DNA Identification from Sebaceous Sweat Fingerprint Deposits on Corpse Integuments
The paper presents the results of a pilot molecular genetic study of sweat and oil residue left by the fingertips and hand palms of male volunteers (donors) on various regions of the skin surface of dead bodies (recipients) of both sexes. In cases of contact with female recipients donor-specific allele combinations were obtained for only 11.6% of autosomal loci and 12.9% of Y-chromosomal loci. Donor-specific traits were absent in 68.4% of autosomal loci and 87.1% of Y-chromosomal loci. In cases of contact with male recipients the full genetic profile was obtained for 18.6% of autosomal loci, and 64.2% of loci showed a lack of donor-specific alleles. Meanwhile, allelic combinations specific to female recipients were encountered in 40.5% of autosomal loci, and to male recipients – in 34.2% of autosomal loci. Results demonstrate poor adhesion of sweat and oil compounds from donors’ hands to the corpses’ skin, probably due to significant temperature differences between contact surfaces
Cerebrovascular and Neuroprotective Effects of Adamantane Derivative
Objectives. The influence of 5-hydroxyadamantane-2-on was studied on the rats’ brain blood flow and on morphological state of brain tissue under the condition of brain ischemia. The interaction of the substance with NMDA receptors was also studied. Methods. Study has been implemented using the methods of local blood flow registration by laser flowmeter, [3H]-MK-801binding, and morphological examination of the brain tissue. We used the models of global transient ischemia of the brain, occlusion of middle cerebral artery, and hypergravity ischemia of the brain. Results. Unlike memantine, antagonist of glutamatergic receptors, the 5-hydroxyadamantane-2-on does not block NMDA receptors but enhances the cerebral blood flow of rats with brain ischemia. This effect is eliminated by bicuculline. Under conditions of permanent occlusion of middle cerebral artery, 5-hydroxyadamantane-2-on has recovered compensatory regeneration in neural cells, axons, and glial cells, and the number of microcirculatory vessels was increased. 5-Hydroxyadamantane-2-on was increasing the survival rate of animals with hypergravity ischemia. Conclusions. 5-Hydroxyadamantane-2-on, an adamantane derivative, which is not NMDA receptors antagonist, demonstrates significant cerebrovascular and neuroprotective activity in conditions of brain ischemia. Presumably, the GABA-ergic system of brain vessels is involved in mechanisms of cerebrovascular and neuroprotective activity of 5-hydroxyadamantane-2-on