Titanium and platinum samples as components of bimetallic implants for the osteoregeneration process have been modified in solutions modeling biological systems and studied by means of cyclic ...voltammetry, electrochemical impedance spectroscopy and scanning probe microscopy. While aspartic and glutamic acids did not adsorb significantly on platinum in the potential region investigated, the presence of the amino acids affects oxide layer growth on the titanium surface under anodic polarization. The two studied amino acids behave differently on the titanium electrode surface due to differences in adsorption modes of these substances. The adsorption of the glutamic acid depends on the polarization potential to a large extent, and most of quantitative adsorption characteristics (EIS data, the surface roughness) undergo drastic change at the polarization potential value of 750 mV (vs. Ag/AgCl) in the presence of this substance. Equivalent circuit modeling of the surface processes has been carried out, and a scheme for aspartic and glutamic acid adsorption onto the titanium surface has proposed.
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•Glutamic acid adsorption is determined by potential applied to the titanium electrode.•Aspartic acid adsorbs on a titanium electrode surface through both carboxylic groups.•Titanium surface characteristics depend on both potential and amino acid presence.•Dicarboxylic amino acids interact strongly with a titanium electrode surface.•Aspartic and glutamic amino acids adsorption on platinum electrode is negligible.
The Advanced Laser Interferometer Gravitational-Wave Observatory and Advanced Virgo observatories recently discovered gravitational waves from a binary neutron star inspiral. A short gamma-ray burst ...that followed the merger of this binary was also recorded by Fermi gamma-ray burst monitor and International Gamma-Ray Astrophysics Laboratory, indicating particle acceleration by the source. The precise location of the event was determined by optical detections of emission following the merger. We searched for high-energy neutrinos from the merger in the energy range of 1 TeV–100 PeV using the Baikal Gigaton Volume Detector. No neutrinos directionally coincident with the source were detected within ±500 s around the merger time, as well as during a 14-day period after the gravitational wave detection. We derived 90% C.L. upper limits on the neutrino fluence from GW170817 during a ±500 s window centered on the gravitational wave trigger time, and a 14-day window following the gravitational wave signal under the assumption of an
E
−2
neutrino energy spectrum.
The 1-cubic km deep Baikal-GVD underwater Cherenkov detector, a new-generation neutrino telescope, is now being deployed in Lake Baikal. The telescope’s status is described and the first physical ...results from its operation are presented.
An experimental scientific equipment for implementing temperature-controlled protein crystallization in capillaries under microgravity has been developed, fabricated, and tested. This crystallization ...method, providing on-line separate control of crystal growth both in the stage of nucleation of crystals and during their further growth, requires small amounts of protein solution. The equipment has been tested on board of Foton-M4 spacecraft (growth of lysozyme protein crystals of high structural quality in microgravity) using a cyclogram developed in ground-based experiments. The results obtained have demonstrated efficiency and importance of the developed equipment and method for growing biomacromolecular crystals of high-structural quality.
A method is described for high-quality protein crystal solution growth with the help of localized action of a thermal control field. A mathematical model has been developed and computational ...investigation has been performed of the processes of lysozyme crystallization from a homogeneous aqueous solution in the crystallization volume as well as crystal growth by counter-diffusion. The mathematical model describes crystal nucleation and growth depending on the local supersaturation and temperature as well as heat-and-mass exchange within the entire volume of the solution including the protein crystals.
•Method of protein crystal growth under thermal control field is presented.•Mathematical model for the process of lysozyme crystallization is presented.•It describes crystal growth depending on the local supersaturation and temperature.
Baikal-GVD: status and prospects Avrorin, A.D.; Avrorin, A.V.; Aynutdinov, V.M. ...
EPJ Web of Conferences,
01/2018, Letnik:
191
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
Baikal-GVD is a next generation, kilometer-scale neutrino telescope under construction in Lake Baikal. It is designed to detect astrophysical neutrino fluxes at energies from a few TeV up to 100 PeV. ...GVD is formed by multi-megaton subarrays (clusters). The array construction started in 2015 by deployment of a reduced-size demonstration cluster named "Dubna" . The first cluster in it’s baseline configuration was deployed in 2016, the second in 2017 and the third in 2018. The full-scale GVD will be an array of ~10.000 light sensors with an instrumented volume about of 2 cubic km. The first phase (GVD-1) is planned to be completed by 2020-2021. It will comprise 8 clusters with 2304 light sensors in total. We describe the design of Baikal-GVD and present selected results obtained in 2015 - 2017.
The results of observations of the pulsar B0301+19 (J0304+1932) carried out on the Large Scanning Antenna of the Pushchino Radio Astronomy Observatory at 111 MHz during 2012–2017 are analyzed. The ...regular generation of powerful individual pulses at the longitudes of both components of the mean profile of the pulsar, classified as giant pulses, was observed. The most powerful of these pulses had a peak flux density of ≈935 Jy and a pulse energy of ≈6930 Jyms. The highest excess of the flux density relative to the value for the mean profile in a session was 93.7. The mean full width at half maximum of the most powerful giant pulse at was 2.8ms, with the width of the corresponding component in the mean profile being about 10 ms. The distributions of the peak flux densities and pulse energies of these anomalously strong pulses are complex, and cannot be reduced to a simple lognormal or power-law distribution over the entire range of values.
Recent achievements of the ATLAS and CMS experiments at the Large Hadron Collider searching for a Higgs boson are summarized. A new particle with the mass of 125 GeV and properties expected for the ...Standard Model Higgs boson was discovered three years ago in these experiments in proton-proton collisions when analyzing part of the data taken at the centre-of-mass energies 7 TeV and 8 TeV in 2011 and 2012 year exposures. Today all the data are processed and fully analyzed. Experimental results of studies of individual Higgs boson decay channels as well as their combination to extract such properties as mass, signal strength, coupling constants, spin and parity are reviewed. All experimental results are found to be compatible with the Standard Model predictions.
ABSTRACT
Baikal-GVD has recently published its first measurement of the diffuse astrophysical neutrino flux, performed using high-energy cascade-like events. We further explore the Baikal-GVD cascade ...data set collected in 2018–2022, with the aim to identify possible associations between the Baikal-GVD neutrinos and known astrophysical sources. We leverage the relatively high angular resolution of the Baikal-GVD neutrino telescope (2–3 deg.), made possible by the use of liquid water as the detection medium, enabling the study of astrophysical point sources even with cascade events. We estimate the telescope’s sensitivity in the cascade channel for high-energy astrophysical sources and refine our analysis prescriptions using Monte-Carlo simulations. We primarily focus on cascades with energies exceeding 100 TeV, which we employ to search for correlation with radio-bright blazars. Although the currently limited neutrino sample size provides no statistically significant effects, our analysis suggests a number of possible associations with both extragalactic and Galactic sources. Specifically, we present an analysis of an observed triplet of neutrino candidate events in the Galactic plane, focusing on its potential connection with certain Galactic sources, and discuss the coincidence of cascades with several bright and flaring blazars.
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