Two flares with one shock: the interesting case of 3C 454.3

The quasar 3C 454.3 is a blazar known for its rapid and violent outbursts seen across the electromagnetic spectrum. Using γ-ray, X-ray, multiband optical, and very-long-baseline interferometric data we investigate the nature of two such events that occurred in 2013 and 2014 accompanied by strong variations in optical polarization, including a ~230° electric vector position angle (EVPA) rotation. Our results suggest that a single disturbance was responsible for both flaring events. We interpret the disturbance as a shock propagating down the jet. Under this interpretation the 2013 flare originated most likely due to changes in the viewing angle caused by perhaps a bent or helical trajectory of the shock upstream of the radio core. The 2014 flare and optical polarization behavior are the result of the shock exiting the 43 GHz radio core, suggesting that shock crossings are one of the possible mechanisms for EVPA rotations.Accepted manuscrip

Methodological approaches and practices for assessing consumers' health risks caused by durable goods (on the example of construction and finishing materials)

The article deals with an issue related to risk assessment as a criterion of durable consumer goods safety for population health; construction materials and finishing materials are a very relevant example of such goods. We showed that legislative and methodological grounds for assessing such risks were not sufficient. So we developed approaches to risk assessment on the basis of evolution models which allowed to examine risks growth under chronic exposure. We revealed that even if certain goods con-formed to sanitary standards set forth by technical regulations they could still cause unacceptable health risks for consumers. And the risks tended to grow dramatically when several goods with similar or identical hazardous effects were consumed together. We performed epidemiologic and profound medical-biological examinations and obtained authentic mathematical de-pendencies of correlation between exposure and consumer health disorders; these models are adequate to the data taken from relevant scientific literature. We tested methodological approaches to application of the detected "dose - effect" dependencies for evolution modeling. These approaches were tried out in real-life situations when certain construction and finishing materials were used in precast frame low-rise housing construction. We proved that long living in houses which were built with the use of 7–8 and more polymer-containing materials formed unacceptable risks for citizens' health after 10-12 years. The results we obtained helped to justify a decision that people should moved houses as it was unacceptable to live in them any longer; it was also considered inadvisable to use newly-built and still uninhabited houses of the studied lines for constant living. Basically, these methodical approaches can be applied in assessing risks caused by a wide range of durable consumer goods

Practice and prospects of proving harm to human health caused by atmospheric air pollution and indoor air in pre-trial and trial

Analysis of judicial practice on established cases of injuries caused by the negative impact of atmospheric air and indoor air and compensation of damages for the past 10 years has been made. The most common causes of complaints of citizens to the court with a request for compensation for damage to health due to the negative impact of air pollution are revealed. The most common causes are: the presence of odors in the implementation of the production activities of enterprises and organizations; violation of hygienic standards in residential areas; location of residential buildings within the boundaries of the sanitary protection zone; mismatch of construction, decoration materials and furniture requirements of the legislation; implementation of industrial activity in a residential area in violation of the law; and the deterioration of human health caused by the described violations. It has been shown that more than half of the requests for compensation for harm caused by the air pollution are not to be fulfilled. The compensation of damage is denied due to lack of evidence of noncompliance of air quality to hygienic requirements, the causal link between the activities of the entity and violation of the right to a healthy environment, and / or failure to prove the fact of harm to public health or the threat of such damage

Establishment of murine hybridoma cells producing antibodies against spike protein of sars‐cov‐2

In 2020 the world faced the pandemic of COVID‐19 severe acute respiratory syndrome caused by a new type of coronavirus named SARS‐CoV‐2. To stop the spread of the disease, it is crucial to create molecular tools allowing the investigation, diagnoses and treatment of COVID‐19. One of such tools are monoclonal antibodies (mAbs). In this study we describe the development of hybridoma cells that can produce mouse mAbs against receptor binding domain of SARS‐CoV‐2 spike (S) protein. These mAbs are able to specifically detect native and denatured S proteins in all tested applications, including immunoblotting, enzyme‐linked immunosorbent assay, immunofluorescence staining of cells and immunohistochemical staining of paraffin embedded patients’ tissue samples. In addition, we showed that the obtained mAbs can efficiently block SARS‐ CoV‐2 infection in in vitro experiments. Finally, we determined the amino acid sequence of light and heavy chains of the mAbs. This information will allow the use of corresponding peptides to establish genetically engineered therapeutic antibodies. To date multiple mAbs against SARS‐CoV‐ 2 proteins have been established, however, bigger sets of various antibodies will allow the detection and neutralization of SARS‐CoV‐2, even if the virus acquires novel mutations. © 2020, MDPI AG. All rights reserved

Rare-Earth Complexes with the 5,5′-Bitetrazolate Ligand – Synthesis, Structure, Luminescence Properties, and Combustion Catalysis

A complete series of complexes of the lanthanides and yttrium (except radioactive Pm) with the 5,5′-bitetrazolate (BT2–) ligand were synthesized from sodium 5,5′-bitetrazolate and available rare-earth (RE) salts. Eight new complexes were structurally characterized by single-crystal XRD. The [M(BT)(H2O)7]2[BT]·6H2O [M = Pr (1), Gd (2)] complexes are isomorphous and consist of [M(BT)(H2O)7]+ ions in which only one BT2– ligand acts as a chelate for each metal center. The complexes [M(H2O)8]2[BT]3·4H2O [M = Y (3), Dy (4), Ho (5), Tm (6), Yb (7), Lu (8)] are saltlike compounds that do not exhibit any significant metal–nitrogen contacts. Luminescence was very informative for the determination of the number of inner-sphere coordinated water molecules in the solid samples. Despite its low luminescence intensity owing to its high hydrate composition, the deuterated europium complex exhibited an internal quantum yield of 44 %. The catalytic activities of the 5,5′-bitetrazolate salts for the decomposition and combustion reactions of energetic materials were tested. Although no effect was found for nitramine (HMX) explosive, the impact of the salts on the thermolysis of ammonium perchlorate (AP) was established. The addition of 5 % [Dy(H2O)8]2[BT]3·4H2O decreases the temperature at the maximum reaction rate by 100 °C. The catalytic effect during combustion is apparently masked by the inhibitory influence of water; however, for [Pr(BT)(H2O)7]2[BT]·6H2O, a 20 % increase in the AP burning rate was observed. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei

Rare-Earth Complexes with the 5,5′-Bitetrazolate Ligand – Synthesis, Structure, Luminescence Properties, and Combustion Catalysis

A complete series of complexes of the lanthanides and yttrium (except radioactive Pm) with the 5,5′-bitetrazolate (BT2–) ligand were synthesized from sodium 5,5′-bitetrazolate and available rare-earth (RE) salts. Eight new complexes were structurally characterized by single-crystal XRD. The [M(BT)(H2O)7]2[BT]·6H2O [M = Pr (1), Gd (2)] complexes are isomorphous and consist of [M(BT)(H2O)7]+ ions in which only one BT2– ligand acts as a chelate for each metal center. The complexes [M(H2O)8]2[BT]3·4H2O [M = Y (3), Dy (4), Ho (5), Tm (6), Yb (7), Lu (8)] are saltlike compounds that do not exhibit any significant metal–nitrogen contacts. Luminescence was very informative for the determination of the number of inner-sphere coordinated water molecules in the solid samples. Despite its low luminescence intensity owing to its high hydrate composition, the deuterated europium complex exhibited an internal quantum yield of 44 %. The catalytic activities of the 5,5′-bitetrazolate salts for the decomposition and combustion reactions of energetic materials were tested. Although no effect was found for nitramine (HMX) explosive, the impact of the salts on the thermolysis of ammonium perchlorate (AP) was established. The addition of 5 % [Dy(H2O)8]2[BT]3·4H2O decreases the temperature at the maximum reaction rate by 100 °C. The catalytic effect during combustion is apparently masked by the inhibitory influence of water; however, for [Pr(BT)(H2O)7]2[BT]·6H2O, a 20 % increase in the AP burning rate was observed. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei

The beamed jet and quasar core of the distant blazar 4C 71.07

The object 4C 71.07 is a high-redshift blazar whose spectral energy distribution shows a prominent big blue bump and a strong Compton dominance. We present the results of a 2- yr multiwavelength campaign led by the Whole Earth Blazar Telescope (WEBT) to study both the quasar core and the beamed jet of this source. The WEBT data are complemented by ultraviolet and X-ray data from Swift, and by γ-ray data by Fermi. The big blue bump is modelled by using optical and near-infrared mean spectra obtained during the campaign, together with optical and ultraviolet quasar templates. We give prescriptions to correct the source photometry in the various bands for the thermal contribution, in order to derive the non-thermal jet flux. The role of the intergalactic medium absorption is analysed in both the ultraviolet and X-ray bands.We provide opacity values to deabsorb ultraviolet data, and derive a best-guess value for the hydrogen column density of Nbest H = 6.3 × 10 cmthrough the analysis of X-ray spectra.We estimate the disc and jet bolometric luminosities, accretion rate, and black hole mass. Light curves do not show persistent correlations among flux changes at different frequencies. We study the polarimetric behaviour and find no correlation between polarization degree and flux, even when correcting for the dilution effect of the big blue bump. Similarly, wide rotations of the electric vector polarization angle do not seem to be connected with the source activity.© 2019 The Author(s).We acknowledge financial contribution from the agreement ASI-INAF n.2017-14-H.0 and from the contract PRIN-SKA-CTA-INAF 2016. PR and SV acknowledge contract ASI-INAF I/004/11/0. We acknowledge support by Bulgarian National Science Programme 'Young Scientists and Postdoctoral Students 2019', Bulgarian National Science Fund under grant DN18-10/2017 and National RI Roadmap Projects DO1-157/28.08.2018 and DO1-153/28.08.2018 of the Ministry of Education and Science of the Republic of Bulgaria. GD and OV gratefully acknowledge the observing grant support from the Institute of Astronomy and Rozhen National Astronomical Observatory, Bulgarian Academy of Sciences via bilateral joint research project 'Study of ICRF radio-sources and fast variable astronomical objects' (head -G.Damljanovic). This work is a part of the Projects No. 176011 ('Dynamics and Kinematics of Celestial Bodies and Systems'), No. 176004 ('Stellar Physics'), and No. 176021 ('Visible and Invisible Matter in Nearby Galaxies: Theory and Observations') supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia. This research was partially supported by the Bulgarian National Science Fund of theMinistry of Education and Science under grants DN 08-1/2016, DN 18-13/2017, and KP-06-H28/3 (2018). The Skinakas Observatory is a collaborative project of the University of Crete, the Foundation for Research and Technology -Hellas, and the Max-Planck-Institut fur Extraterrestrische Physik. The St Petersburg University team acknowledges support from Russian Science Foundation grant no. 17-12-01029. The Abastumani team acknowledges financial support by the Shota Rustaveli National Science Foundation under contract FR/217950/16. This work was partly supported by the National Science Fund of the Ministry of Education and Science of Bulgaria under grant DN 08-20/2016, and by funds of the project RD-08-37/2019 of the University of Shumen. The Astronomical Observatory of the Autonomous Region of the Aosta Valley (OAVdA) is managed by the Fondazione Clement Fillietroz-ONLUS, which is supported by the Regional Government of the Aosta Valley, the Town Municipality of Nus and the Unite des Communes valdotaines Mont-Emilius'. The research at the OAVdA was partially funded by two 'Research and Education' grants from Fondazione CR