Adaptation of epizootic brucella strains to the conditions of artificial nutrient media and the body of experimentally infected animals

Brucellosis remains an urgent problem to date. The preservation of brucellosis infection foci in regions with traditionally developed animal husbandry poses a danger of introducing the pathogen into safe territories, spreading among susceptible livestock and the risk of human infection. When fresh foci of brucellosis occur in an area with long-term well-being, objective data on the causative agent of infection are of great importance. The purpose of the research is to obtain an objective result of laboratory studies when diagnosing brucellosis in cattle in a fresh outbreak of infection and to evaluate the effectiveness of a set of diagnostic methods used in the work. The research was carried out in production veterinary and scientific laboratories. It was found that brucella, forming a fresh source of infection in cattle herds against the background of long-term well-being, had active antigenic properties. In 42% of infected animals (5 out of 12 animals), brucella of the epizootic strain caused the synthesis of specific immunoglobulins. Isolated brucella cultures were characterized by a weakly expressed ability to adapt to the conditions of an artificial nutrient medium and the body of laboratory animals. In the conducted studies, the probability of isolating the causative agent of brucellosis from animals that respond positively to serological examination was 20%. The objective data obtained on the properties of brucellosis pathogens circulating among susceptible animals in a fresh outbreak of infection made it possible to determine its species differences; establish factors and ways of introducing brucella, predict the course of infectious and epizootic processes, make a timely decision on carrying out health and preventive measures using effective methods and means

Helium identification with LHCb

The identification of helium nuclei at LHCb is achieved using a method based on measurements of ionisation losses in the silicon sensors and timing measurements in the Outer Tracker drift tubes. The background from photon conversions is reduced using the RICH detectors and an isolation requirement. The method is developed using pp collision data at √(s) = 13 TeV recorded by the LHCb experiment in the years 2016 to 2018, corresponding to an integrated luminosity of 5.5 fb-1. A total of around 105 helium and antihelium candidates are identified with negligible background contamination. The helium identification efficiency is estimated to be approximately 50% with a corresponding background rejection rate of up to O(10^12). These results demonstrate the feasibility of a rich programme of measurements of QCD and astrophysics interest involving light nuclei

Measurement of forward charged hadron flow harmonics in peripheral PbPb collisions at √sNN = 5.02 TeV with the LHCb detector

Flow harmonic coefficients, v n , which are the key to studying the hydrodynamics of the quark-gluon plasma (QGP) created in heavy-ion collisions, have been measured in various collision systems and kinematic regions and using various particle species. The study of flow harmonics in a wide pseudorapidity range is particularly valuable to understand the temperature dependence of the shear viscosity to entropy density ratio of the QGP. This paper presents the first LHCb results of the second- and the third-order flow harmonic coefficients of charged hadrons as a function of transverse momentum in the forward region, corresponding to pseudorapidities between 2.0 and 4.9, using the data collected from PbPb collisions in 2018 at a center-of-mass energy of 5.02 TeV . The coefficients measured using the two-particle angular correlation analysis method are smaller than the central-pseudorapidity measurements at ALICE and ATLAS from the same collision system but share similar features

Curvature-bias corrections using a pseudomass method

Momentum measurements for very high momentum charged particles, such as muons from electroweak vector boson decays, are particularly susceptible to charge-dependent curvature biases that arise from misalignments of tracking detectors. Low momentum charged particles used in alignment procedures have limited sensitivity to coherent displacements of such detectors, and therefore are unable to fully constrain these misalignments to the precision necessary for studies of electroweak physics. Additional approaches are therefore required to understand and correct for these effects. In this paper the curvature biases present at the LHCb detector are studied using the pseudomass method in proton-proton collision data recorded at centre of mass energy √(s)=13 TeV during 2016, 2017 and 2018. The biases are determined using Z→μ + μ - decays in intervals defined by the data-taking period, magnet polarity and muon direction. Correcting for these biases, which are typically at the 10-4 GeV-1 level, improves the Z→μ + μ - mass resolution by roughly 18% and eliminates several pathological trends in the kinematic-dependence of the mean dimuon invariant mass

Study of CP violation in B0 → DK⋆(892)0 decays with D → Kπ(ππ), ππ(ππ), and KK final states

A measurement of CP-violating observables associated with the interference of B0 → D0K⋆ (892)0 and B0 → D¯ 0K⋆ (892)0 decay amplitudes is performed in the D0 → K∓π ±(π +π −), D0 → π +π −(π +π −), and D0 → K+K− fnal states using data collected by the LHCb experiment corresponding to an integrated luminosity of 9 fb−1 . CP-violating observables related to the interference of B0 s → D0K¯ ⋆ (892)0 and B0 s → D¯ 0K¯ ⋆ (892)0 are also measured, but no evidence for interference is found. The B0 observables are used to constrain the parameter space of the CKM angle γ and the hadronic parameters r DK⋆ B0 and δ DK⋆ B0 with inputs from other measurements. In a combined analysis, these measurements allow for four solutions in the parameter space, only one of which is consistent with the world average

Ring opening in 1,2,3,4-tetrahydrochromeno[3,2-c]pyridines under the action of electron-deficient alkynes

2-Vinyl substituted chromones were obtained by the reaction between 1,2,3,4-tetrahydrochromeno[3,2-c]pyridines and electron-deficient alkynes. © 201

Mass Spectrometry in Petroleum Chemistry (Petroleomics) (Review)

Abstract: The review discusses the achievements of the last 5 years in the field of using mass spectrometry for the analysis of crude oils and some oil refining products. The presented materials are systematized according to properties of the analyzed compounds and ionization techniques used. The capabilities and disadvantages of existing approaches are discussed. © 2019, Pleiades Publishing, Ltd

Ring opening in 1,2,3,4-tetrahydrochromeno[3,2-c]pyridines under the action of electron-deficient alkynes

2-Vinyl substituted chromones were obtained by the reaction between 1,2,3,4-tetrahydrochromeno[3,2-c]pyridines and electron-deficient alkynes. © 201