Laser spectoscopy of Mandelstems - Brillian scattering in aqueous nonelectrolyte solutions

In this work we developed a method of laser spectroscopy to study the frequency shift of Mandelshtam-Brillouin components in the fine structure of Reyleigh line, which are origin due to the pressure fluctuations. The method allows to study a character of hypersound (~109 Hz)propagation in a critical region of a thermodynamic instability. Analysis of a complex of experimental material , presented in the paper, allows one to conclude that in aqueous solutions of non-electrolytes at critical concentration there is a whole structural transformations in solutions at the singular point temperature in “temperature-concentration” coordinate

First record of the whip-lash squid, Mastigoteuthis agassizii verrill, 1881 (Mollusca: Cephalopoda: Mastigoteuthidae) in the subarctic atlantic, with notes on its morphology and biology

© 2018 Informa UK Limited, trading as Taylor & Francis Group. Cephalopods are an important, abundant and taxonomically diverse component of the bathypelagic realm. However, their biology, ecology and distribution are poorly known. Specimens of Mastigoteuthis agassizii (Mastigoteuthidae) have been captured in the southern part of the Denmark Strait, which is at approximately 65°N. This site is approximately 550 km north of the previously most northern known border of the Mastigoteuthidae range. The main goal of this paper is to provide an extended morphological description and biological analysis of M. agassizii, the first species of the Mastigoteuthidae caught in the Subarctic Atlantic. Despite sample collection at 534 deep-water stations in the area, only two specimens were captured, indicating the rarity of this species in the northern part of its range. We suggest that the typical range of this species is bathyal depths throughout the North Atlantic to the Subarctic, but not through the Denmark and Davis Straits to the Arctic. These findings coincide with the geographic border of the Northern Atlantic boreal bathyal province, which is warmer and more saline compared to the Arctic province further to the north. We also provide the first descriptions of the radula and reproductive system of M. agassizii. The female had synchronous ovulation, fecundity of approximately 23,000 oocytes, oocyte resorption having not been found, most likely due to the early maturity stage of the female. The males, as proven by our sample and additional photo in other source, were found to have the distal part of the penis enlarged, divided into two valves and pigmented, possibly indicating they can protrude outside the mantle cavity. This enlarged valved part, as it is supposed in the literature for other deep-water squid families having it, may be used as an analogue to the lacking hectocotylus

Oxygen-glucose deprivation induces ATP release via maxi-anion channels in astrocytes

ATP represents a major gliotransmitter that serves as a signaling molecule for the cross talk between glial and neuronal cells. ATP has been shown to be released by astrocytes in response to a number of stimuli under nonischemic conditions. In this study, using a luciferin-luciferase assay, we found that mouse astrocytes in primary culture also exhibit massive release of ATP in response to ischemic stress mimicked by oxygen-glucose deprivation (OGD). Using a biosensor technique, the local ATP concentration at the surface of single astrocytes was found to increase to around 4 μM. The OGD-induced ATP release was inhibited by Gd3+ and arachidonic acid but not by blockers of volume-sensitive outwardly rectifying Cl− channels, cystic fibrosis transmembrane conductance regulator (CFTR), multidrug resistance-related protein (MRP), connexin or pannexin hemichannels, P2X7 receptors, and exocytotic vesicular transport. In cell-attached patches on single astrocytes, OGD caused activation of maxi-anion channels that were sensitive to Gd3+ and arachidonic acid. The channel was found to be permeable to ATP4− with a permeability ratio of PATP/PCl = 0.11. Thus, it is concluded that ischemic stress induces ATP release from astrocytes and that the maxi-anion channel may serve as a major ATP-releasing pathway under ischemic conditions

PHYSICAL SIMULATION OF COLD ROLLING OF ULTRA-FINE GRAINED AL 5083 ALLOY TO STUDY MICROSTRUCTURE EVOLUTION

Abstract. Recent investigations have demonstrated that ultra-fine grained (UFG) Al 5xxx alloys have a significant potential for industrial applications due to their enhanced mechanical and functional properties. The Al 5xxx alloys often have to undergo hot/cold rolling metalforming operations for fabrication of near-net shape products since they are widely used in form of sheets in marine, transport, and chemical engineering. The development of hot/cold rolling routes for the UFG metallic materials are very expensive due to much higher cost of the UFG metallic materials and time consuming due to numerous experimental trials. The objective of this work is to perform physical simulation of cold rolling of the UFG Al 5083 alloy obtained via equal channel angular pressing with parallel channels and to analyze the effect of cold rolling on the microstucture and microhardness of the material. It is demonstrated that physical simulation of metalforming processes for the UFG metallic materials can significantly reduce the amount of material required for development of processing routes and increase the efficiency of experimental work

Tunka Advanced Instrument for cosmic rays and Gamma Astronomy

The paper is a script of a lecture given at the ISAPP-Baikal summer school in 2018. The lecture gives an overview of the Tunka Advanced Instrument for cosmic rays and Gamma Astronomy (TAIGA) facility including historical introduction, description of existing and future setups, and outreach and open data activities.Comment: Lectures given at the ISAPP-Baikal Summer School 2018: Exploring the Universe through multiple messengers, 12-21 July 2018, Bol'shie Koty, Russi