EFFECT OF THE PROPHAGE CTXΦ DELETION UPON PHENOTYPIC PROPERTIES IN STRAINS OF VIBRIO CHOLERAE BIOVAR EL TOR, ASSOCIATED WITH VIRULENCE AND PERSISTENCE

Objective of the study is to evaluate the influence of CTXφ prophage deletion, which carries ctxAB genes, on phenotypical properties associated with pathogenicity or biofilm formation in non-toxigenic mutants. Materials and methods. Utilized have been the clinical strains of Vibrio cholerae biovar El Tor and their spontaneous non-toxigenic mutants that lost CTXφ prophage. Applied have been microbiological and biochemical methods, inoculation of model animals with cells of the strains under study. Results and conclusions. The results of comparative analysis of phenotypic properties in isogenic toxigenic and non-toxigenic strains of Vibrio cholerae biovar El Tor, which lost CTXφ prophage encoding the cholera toxin, are represented. It is established that the deletion of CTXφ prophage leads to the simultaneous change of several phenotypic properties associated with virulence (colonizing ability, production of soluble hemagglutinin/protease and heat labile hemolysin/cytolysin) and biofilm formation (motility, exopolysaccharide biosynthesis) in spontaneous non-toxigenic mutants. It is suggested that the reason for these phenotypic changes in the mutants might be the changes in activity of the related to each other regulatory genes controlling virulence and biofilm formation process in cholera agent

The neutron 'thunder' accompanying the extensive air shower

Simulations show that neutrons are the most abundant component among extensive air shower hadrons. However, multiple neutrons which appear with long delays in neutron monitors nearby the EAS core ('neutron thunder') are mostly not the neutrons of the shower, but have a secondary origin. The bulk of them is produced by high energy EAS hadrons hitting the monitors. The delays are due to the termalization and diffusion of neutrons in the moderator and reflector of the monitor accompanied by the production of secondary gamma-quanta. This conclusion raises the important problem of the interaction of EAS with the ground, the stuff of the detectors and their environment since they have often hydrogen containing materials like polyethilene in neutron monitors. Such interaction can give an additional contribution to the signal in the EAS detectors. It can be particularly important for the signals from scintillator or water tank detectors at km-long distances from the EAS core where neutrons of the shower become the dominant component after a few mcsec behind the EAS front.Comment: 12 pages, 4 figures, accepted by J.Phys.G: Nucl.Part.Phy

Latin American experience in constitutional and legal guarantees of freedom of the media

The objective of the research was to analyze the Latin American experience in constitutional guarantees regarding freedom of expression in the media. The document summarizes the results of a comparative legal study dedicated to the texts included in the constitutions of the Latin American states regarding the identification of norms that guarantee the freedom of the media in them. It has been established that most of the declared constitutions contain traditional guarantees of media freedom expressed in the legalization of this substantive freedom, its implementation without censorship and restrictions under the threat of responsibility for its abus

Модель операций взлета и посадки для расчета пропускной способности аэродрома

The procedures for takeoff and landing of aircraft flow are discussed. An approach to the construction of a model for calculation of aerodrome capacity is proposed. Decomposition of model is conducted and one of its elements - the approach mode is investigated. The estimation of the time interval for this mode and limitations on the minimum distances between aircraft in the stream are shown.Рассмотрены процедуры взлета и посадки потока ВС нескольких категорий. Предложен подход к построению модели расчета пропускной способности аэродрома. Проведена декомпозиция модели и исследован один из ее элементов - режим захода на посадку. Проведена оценка временного интервала для этого режима и получены ограничения на минимально допустимые расстояния между ВС в потоке

АЛГОРИТМИЧЕСКАЯ ПОДДЕРЖКА КОНЦЕПЦИИ ОБЩЕСИСТЕМНОГО УПРАВЛЕНИЯ ИНФОРМАЦИЕЙ

The theoretical problems of computer support for the "System Wide Information Management" concept, which was proposed by experts of the International Civil Aviation Organization, are discussed. Within the framework of its provisions certain new requirements for all initial stages of air traffic management preceding the direct aircrafts control are formulated. Algorithmic instruments for ensuring a conflictlessness of a summary plan for the use of airspace during the plan’s implementation are analyzed.Обсуждаются теоретические проблемы компьютерного обеспечения концепции общесистемного управления информацией, выдвинутой экспертами международной организации гражданской авиации. В рамках ее положений формулируются новые требования к этапам процесса организации воздушного движения, предваряющим непосредственное управление полетами. Анализируются также алгоритмические средства для поддержания бесконфликтности сводного плана использования воздушного пространства в ходе его выполнения

Measurement of the velocity of neutrinos from the CNGS beam with the Large Volume Detector

We report the measurement of the time-of-flight of ~17 GeV muon neutrinos on the CNGS baseline (732 km) with the Large Volume Detector (LVD) at the Gran Sasso Laboratory. The CERN-SPS accelerator has been operated from May 10th to May 24th 2012, with a tightly bunched-beam structure to allow the velocity of neutrinos to be accurately measured on an event-by-event basis. LVD has detected 48 neutrino events, associated to the beam, with a high absolute time accuracy. These events allow to establish the following limit on the difference between the neutrino speed and the light velocity: -3.8 x 10-6 < (v-c)/c < 3.1 x 10-6 (at 99% C.L.). This value is an order of magnitude lower than previous direct measurements

First CNGS events detected by LVD

The CERN Neutrino to Gran Sasso (CNGS) project aims to produce a high energy, wide band $\nu_{\mu}$ beam at CERN and send it toward the INFN Gran Sasso National Laboratory (LNGS), 732 km away. Its main goal is the observation of the $\nu_{\tau}$ appearance, through neutrino flavour oscillation. The beam started its operation in August 2006 for about 12 days: a total amount of $7.6~10^{17}$ protons were delivered to the target. The LVD detector, installed in hall A of the LNGS and mainly dedicated to the study of supernova neutrinos, was fully operating during the whole CNGS running time. A total number of 569 events were detected in coincidence with the beam spill time. This is in good agreement with the expected number of events from Montecarlo simulations.Comment: Accepted for publication by the European Physical Journal C ; 7 pages, 11 figure

On-line recognition of supernova neutrino bursts in the LVD detector

In this paper we show the capabilities of the Large Volume Detector (INFN Gran Sasso National Laboratory) to identify a neutrino burst associated to a supernova explosion, in the absence of an "external trigger", e.g., an optical observation. We describe how the detector trigger and event selection have been optimized for this purpose, and we detail the algorithm used for the on-line burst recognition. The on-line sensitivity of the detector is defined and discussed in terms of supernova distance and electron anti-neutrino intensity at the source.Comment: Accepted for pubblication on Astroparticle Physics. 13 pages, 10 figure

Experience in Studying Herd and Individual Immunity to the SARS-CoV-2 Virus in Medical Workers

The aim was to study SARS-CoV-2 immunity among medical workers in Kazan.Materials and methods. Studied were serum samples from 348 medical workers from 10 medical organizations in Kazan, divided into groups according to the level of the alleged risk of infection of employees. To determine IgG, a two-stage direct version of the solid-phase ELISA and the test-system “SARS-CoV-2-IgG-ELISA-BEST” (Russia) were used.Results and discussion. At the time of the study and over the previous three months, the examined medical workers had no symptoms of acute respiratory viral infection or respiratory tract infections; there were negative results of examining nasopharyngeal/ oropharyngeal swabs for the presence of SARS-CoV-2 RNA. Seroprevalence for IgG to SARS-CoV-2 virus for different medical organizations in Kazan ranged within the scope of 3.3–30.8 % and averaged 16.4 %. The wide variation in seroprevalence values in medical workers of different medical organizations may indicate different levels of intensity of professional contacts and the effectiveness of anti-epidemic measures in these medical organizations. Among medical workers with seropositive results, the prevalence of persons with a very high coefficient of positivity (49.1 %) is observed, which characterizes high level of antiviral antibodies. The presence of a high proportion of seropositive individuals among medical workers, who have had an asymptomatic form of COVID-19 confirms the high intensity of the latent epidemic process, which must be taken into account when organizing preventive measures, including vaccination

АНЕСТЕЗИЯ У БОЛЬНЫХ С ХИРУРГИЧЕСКОЙ ИНФЕКЦИЕЙ. ВЫБОР МЕТОДА

Possibilities of application of various methods of anesthesia of patients with surgical infections are reviewed in the article. The problems of anesthesia related with peculiarities of the process of surgical infection, localization, and characteristics of surgical treatment, as well as with the initial physical status of the patient determined with the age and severity of accompanying diseases were discussed. В статье рассмотрены возможности проведения различных методов анестезии у больных с хирургической инфекцией. Обсуждены проблемы анестезии, связанные с особенностями течения хирургической инфекции, локализацией и особенностями оперативного лечения, а также с исходным физическим статусом пациента, определяемым возрастом и тяжестью сопутствующих заболеваний.