Using of small-scale quantum computers in cryptography with many-qubit entangled states

We propose a new cryptographic protocol. It is suggested to encode information in ordinary binary form into many-qubit entangled states with the help of a quantum computer. A state of qubits (realized, e.g., with photons) is transmitted through a quantum channel to the addressee, who applies a quantum computer tuned to realize the inverse unitary transformation decoding of the message. Different ways of eavesdropping are considered, and an estimate of the time needed for determining the secret unitary transformation is given. It is shown that using even small quantum computers can serve as a basis for very efficient cryptographic protocols. For a suggested cryptographic protocol, the time scale on which communication can be considered secure is exponential in the number of qubits in the entangled states and in the number of gates used to construct the quantum network

Measurement of high order current correlators

The feasibility of measuring high-order current correlators by means of a linear detector is analyzed. Two different types of measurements are considered: measurement of fluctuation power spectrum and measurement of unequal-time current correlators at fixed points in time. In both cases, formally exact expressions in terms of Keldysh time-ordered electron current operators are derived for the detector output. An explicit time ordering is found for the current correlators under the expectation operator used in measurements of high order unequal-time current correlators. The situation when a detector measures current correlators at different points of a conductor is considered.Comment: 27 page

Genotypes and Subtypes of Hepatitis B Virus Isolates in the Territory of Siberia

Identified are the occurrence, serotypic and genotypic variations of Hepatitis B virus isolates (HBV) among the Novosibirsk region inhabitants (n=2000), native population of the Alarsk District of the Irkutsk Region (n=487) and Shuryshkarsk Township of the Yamalo-Nenets Autonomous District (n=657). Occurrence rate of hepatitis В surface antigen (HBsAg) among different groups of the Novosibirsk Region population varied within the limits of 3,6-35,0 %. It was 8,2 % in Alarsk District, and 3,2 % in Shuryshkarsk Township. HBV isolates of D genotype (92-97 %) prevail among the population of Siberia; few are the cases of A (1,7 %) and C (1,2-8 %) genotypes. The identified varying occurrence of HBV sub-genotypes and HBsAg subtypes in two aboriginal groups of Siberia (D3 sub-genotype and ayw2 subtype - in the Alarsk District, D2 and ayw3 - in Shuryshkarsk Township) suggests the existence of, at least, two isolated HBV virus populations, circulating among different groups of Siberia native population

Detection of the Genetic Material of the Viruses Tacheng uukuvirus and Sara tick phlebovirus in Taiga Ticks Collected in the Sverdlovsk, Tomsk Regions and Primorsky Territory of Russia and Their Phylogeny

Extensive spread of tick-borne diseases poses a significant problem for public health and the health of the population living in endemic areas.The aim of the study was to search, analyze genetic material and identify new viral agents of the Phenuiviridae family in taiga ticks collected in Asian regions of Russia using the method of high throughput sequencing.Materials and methods. The study involved 1460 taiga ticks collected in suburban areas of the Tomsk, Yekaterinburg and Primorsky Territory. The genetic material isolated from ticks was sequenced using Illumina technology followed by phylogenetic analysis.Results and discussion. Analysis of the sequencing results made it possible to detect extended nucleotide sequences of the L-gene fragment characteristic of the Phenuiviridae family viruses. We were able to identify 20 nucleotide sequences the length of 250 bp on average in homogenates of Ixodes persulcatus ticks. Eighteen isolates have been identified as members of the genus Uukuvirus and two isolates have been assigned to the genus Phlebovirus, Phenuiviridae family. Phylogenetic analysis has shown that all isolates of the genus Uukuvirus fall under the cluster of Tacheng tick virus 2 belonging to the species Tacheng uukuvirus. They form a separate phylogenetic group which is closely related to two Romanian variants of 2019. Tacheng tick virus 2 was detected in all three surveyed regions of the Asian part of Russia. Two Tomsk isolates of phlebovirus were classified as Sara tick phlebovirus and they clustered with two isolates of phleboviruses from Karelia. Thus, the genetic material of Tacheng tick virus 2 and Sara tick phlebovirus belonging to two genera of the family Phenuiviridae was found in I. persulcatus ticks collected in three geographically different regions of the Asian part of Russia

Analysis of Ebola virus Zaire 2014 isolates

Analysis of 5 Ebola virus Zaire 2014 isolates passaged in cell cultures or in mice, demonstrated presence of unique mutations in the genome RNA in some cases. All identified nucleotide substitutions are singular, stochastically located, synonymous or fall within non-coding regions. Variability level of nucleotide sequences is equal to 0.005-0.01 %, suggesting extremely high genetic stability of Ebola virus Zaire, the causative agent of the outbreak. Confirmed is suppression of non-synonymous mutations accumulation in ebolavirus variants in the course of time. Detected are alterations in glycosilation sites and mucin-like domain of ebolavirus glycoprotein

Identification of Dengue Fever Markers by Dot Immunoasay

The aim. Development of diagnostic kit for identifying markers of dengue fever at all stages of the disease. Materials and methods. In blood serum from patients with suspected dengue fever, NS1 antigen and specific IgM and IgG were detected by immune chromatography, dot immunoassay, enzyme-linked immunosorbent assay, using commercial test systems, as well as the “Dengue Spectrum” experimental kit. Results and discussion. A diagnostic kit has been developed for the detection of dengue fever markers, based on the mechanism of simultaneous differential detection of the agent NS1 protein and IgM and IgG class antibodies with the formation of specific complexes between markers from the test sample and known capture immune reagents, in a certain order, discretely fixed on a dense substrate. It was found that the effective detection of specific IgG and IgM to dengue virus can be carried out according to the scheme in which IgG is captured on the total antigen of the virus with detection using labeled anti-human IgG antibodies, and IgM is detected by capture on anti-human IgM antibodies with detection using total viral antigen. Detection of dengue virus NS1 protein can be performed using a substrate with immobilized monoclonal antibodies to NS1 and a gold immune sol bound to antibodies against NS1. This protocol of the dot analysis provides the limit for determining the recombinant analogue of the NS1 protein equal to 100 ng/ml. Comparative testing of the kit against the panel of clinical samples showed a good agreement between the results and the data obtained using imported commercial tests. The developed kit can be used for screening clinical samples, both in laboratory and in the field