Onset of quantum thermalization in the Jahn-Teller model.

We investigate the onset of quantum thermalization in a system governed by the Jahn-Teller Hamiltonian, which describes the interaction between a single spin and two bosonic modes. We find that the Jahn-Teller model exhibits a finite-size quantum phase transition between the normal phase and two types of super-radiant phase when the ratios of spin-level splitting to each of the two bosonic frequencies grow to infinity. We test the prediction of the eigenstate thermalization hypothesis in the Jahn-Teller model.

Random matrix theory approach to quantum Fisher information in quantum ergodic systems.

We theoretically investigate quantum parameter estimation in quantum chaotic systems. Our analysis is based on an effective description of quantum ergodic systems in terms of a random matrix Hamiltonian. Based on this approach, we derive an analytical expression for the time evolution of the quantum Fisher information (QFI), which we find to have three distinct timescales.

The Temporal and Geographical Dynamics of Potato Virus Y Diversity in Russia.

Potato virus Y, an important viral pathogen of potato, has several genetic variants and geographic distributions which could be affected by environmental factors, aphid vectors, and reservoir plants. PVY is transmitted to virus-free potato plants by aphids and passed on to the next vegetative generations through tubers, but the effects of tuber transmission in PVY is largely unknown. By using high-throughput sequencing, we investigated PVY populations transmitted to potato plants by aphids in different climate zones of Russia, namely the Moscow and Astrakhan regions.

Signaling and Resistosome Formation in Plant Innate Immunity to Viruses: Is There a Common Mechanism of Antiviral Resistance Conserved across Kingdoms?

Virus-specific proteins, including coat proteins, movement proteins, replication proteins, and suppressors of RNA interference are capable of triggering the hypersensitive response (HR), which is a type of cell death in plants. The main cell death signaling pathway involves direct interaction of HR-inducing proteins with nucleotide-binding leucine-rich repeats (NLR) proteins encoded by plant resistance genes. Singleton NLR proteins act as both sensor and helper.

Designing Stable Antigens with a View to Recombinant Anthrax Vaccine Development.

Anthrax is a disease caused by that affects mammals, including humans. Recombinant protective antigen (rPA) is the most common basis for modern anthrax vaccine candidates. However, this protein is characterised by low stability due to proteolysis and deamidation.

Vaccine Candidate Against COVID-19 Based on Structurally Modified Plant Virus as an Adjuvant.

A recombinant vaccine candidate has been developed based on the major coronaviruses' antigen (S protein) fragments and a novel adjuvant-spherical particles (SPs) formed during tobacco mosaic virus thermal remodeling. The receptor-binding domain and the highly conserved antigenic fragments of the S2 protein subunit were chosen for the design of recombinant coronavirus antigens. The set of three antigens (Co1, CoF, and PE) was developed and used to create a vaccine candidate composed of antigens and SPs (SPs + 3AG).

Plum Pox Virus Strain C Isolates Can Reduce Sour Cherry Productivity.

The impact of plum pox virus (PPV) on sour cherry ( L.) productivity has been studied by comparing the yield of PPV-infected and PPV-free fruit-bearing trees. A total of 152 16- to 17-year-old trees of nine cultivars and hybrids were surveyed in the production orchards (cultivar collection and hybrid testing plots) in the Republic of Tatarstan, Russia.

Enhanced Parameter Estimation with Periodically Driven Quantum Probe.

I propose a quantum metrology protocol for measuring frequencies and weak forces based on a periodic modulating quantum Jahn-Teller system composed of a single spin and two bosonic modes. I show that, in the first order of the frequency drive, the time-independent effective Hamiltonian describes spin-dependent interaction between the two bosonic modes. In the limit of high-frequency drive and low bosonic frequency, the quantum Jahn-Teller system exhibits critical behavior which can be used for high-precision quantum estimation.

CERN-MEDICIS: A Review Since Commissioning in 2017.

The CERN-MEDICIS (MEDical Isotopes Collected from ISolde) facility has delivered its first radioactive ion beam at CERN (Switzerland) in December 2017 to support the research and development in nuclear medicine using non-conventional radionuclides. Since then, fourteen institutes, including CERN, have joined the collaboration to drive the scientific program of this unique installation and evaluate the needs of the community to improve the research in imaging, diagnostics, radiation therapy and personalized medicine. The facility has been built as an extension of the ISOLDE (Isotope Separator On Line DEvice) facility at CERN.

Novel antigen panel for modern broad-spectrum recombinant rotavirus A vaccine.

Purpose: Recombinant rotavirus A vaccines are being developed as an alternative to existing live oral attenuated vaccines. One of the main problems in the production of such vaccines is the genetic diversity of the strains that are in circulation. The goal of this study was to create an antigen panel for modern broad-spectrum recombinant rotavirus A vaccine.

Ra-224 activity, half-life, and 241 keV gamma ray absolute emission intensity: A NIST-NPL bilateral comparison.

The national metrology institutes for the United Kingdom (UK) and the United States of America (USA) have compared activity standards for Ra, an α-particle emitter of interest as the basis for therapeutic radiopharmaceuticals. Solutions of RaCl were assayed by absolute methods, including digital coincidence counting and triple-to-double coincidence ratio liquid scintillation counting. Ionization chamber and high-purity germanium (HPGe) γ-ray spectrometry calibrations were compared; further, a solution was shipped between laboratories for a direct comparison by HPGe spectrometry.

Graphene Flakes for Electronic Applications: DC Plasma Jet-Assisted Synthesis.

The possibility of graphene synthesis (the bottom-up approach) in plasma and the effective control of the morphology and electrical properties of graphene-based layers were demonstrated. Graphene flakes were grown in a plasma jet generated by a direct current plasma torch with helium and argon as the plasma-forming gases. In the case of argon plasma, the synthesized graphene flakes were relatively thick (2-6 nm) and non-conductive.

Two approaches for the stabilization of recombinant protective antigen.

Anthrax is a zoonotic disease caused by the gram-positive spore-forming bacteria . There is a need for safe, highly effective, long-term storage vaccine formulations for mass vaccination. However, the development of new subunit vaccines based on recombinant protective antigen (rPA) faces the problem of vaccine antigen instability.

Distinctive Features of Graphene Synthesized in a Plasma Jet Created by a DC Plasma Torch.

Synthesis of graphene materials in a plasma stream from an up to 40 kW direct current (DC) plasma torch is investigated. These materials are created by means of the conversion of hydrocarbons under the pressure 350-710 Torr without using catalysts, without additional processes of inter-substrate transfer and the elimination of impurities. Helium and argon are used as plasma-forming gas, propane, butane, methane, and acetylene are used as carbon precursors.

Two-qubit quantum gate and entanglement protected by circulant symmetry.

We propose a method for the realization of the two-qubit quantum Fourier transform (QFT) using a Hamiltonian which possesses the circulant symmetry. Importantly, the eigenvectors of the circulant matrices are the Fourier modes and do not depend on the magnitude of the Hamiltonian elements as long as the circulant symmetry is preserved. The QFT implementation relies on the adiabatic transition from each of the spin product states to the respective quantum Fourier superposition states.

Chemical Purification of Terbium-155 from Pseudo-Isobaric Impurities in a Mass Separated Source Produced at CERN.

Four terbium radioisotopes (Tb) constitute a potential theranostic quartet for cancer treatment but require any derived radiopharmaceutical to be essentially free of impurities. Terbium-155 prepared by proton irradiation and on-line mass separation at the CERN-ISOLDE and CERN-MEDICIS facilities contains radioactive CeO and also zinc or gold, depending on the catcher foil used. A method using ion-exchange and extraction chromatography resins in two column separation steps has been developed to isolate Tb with a chemical yield of ≥95% and radionuclidic purity ≥99.

Compensation of the trap-induced quadrupole interaction in trapped Rydberg ions.

The quadrupole interaction between the Rydberg electronic states of a Rydberg ion and the radio frequency electric field of the ion trap is analyzed. Such a coupling is negligible for the lowest energy levels of a trapped ion but it is important for a trapped Rydberg ion due to its large electric quadrupole moment. This coupling cannot be neglected by the standard rotating-wave approximation because it is comparable to the frequency of the trapping electric field.

Analysis of Genetic Diversity of Russian Sour Cherry Plum pox virus Isolates Provides Evidence of a New Strain.

Plum pox virus (PPV) exists as a complex of nine strains adapted to different Prunus hosts. Unusual PPV isolates that do not belong to the known cherry-adapted strains were discovered on sour cherry in Russia. Here, two complete genomes of isolates Tat-2 and Tat-4 were determined by sequencing on the Illumina HiSeq 2500 platform.

Sequence Analysis of Strain C Isolates from Russia Revealed Prevalence of the D96E Mutation in the Universal Epitope and Interstrain Recombination Events.

The understanding of genetic diversity, geographic distribution, and antigenic properties of (PPV) is a prerequisite to improve control of sharka, the most detrimental viral disease of stone fruit crops worldwide. Forty new PPV strain C isolates were detected in sour cherry () from three geographically distant (700⁻1100 km) regions of European Russia. Analysis of their 3'-terminal genomic sequences showed that nineteen isolates (47.

Molecular characterization of Plum pox virus Rec isolates from Russia suggests a new insight into evolution of the strain.

Field isolates of Plum pox virus (PPV), belonging to the strain Rec, have been found for the first time in Russia. Full-size genomes of the isolates K28 and Kisl-1pl from myrobalan and plum, respectively, were sequenced on the 454 platform. Analysis of all known PPV-Rec complete genomes using the Recombination Detection Program (RDP4) revealed yet another recombination event in the 5'-terminal region.

Consensus evaluation of radioactivity-in-soil reference materials in the context of an NPL Environmental Radioactivity Proficiency Test Exercise.

The development of two radioactivity-in-soil reference materials is described - one for peat and one for soil with high sand content. Each bulk material was processed, subdivided and measured before being sent to participants in an NPL Environmental Radioactivity Proficiency Test Exercise. Activity concentrations of radionuclides in each material were determined by 'consensus' evaluations of participants' results using two weighted mean methods.

New highly divergent Plum pox virus isolates infecting sour cherry in Russia.

Unusual Plum pox virus (PPV) isolates (named Tat isolates) were discovered on sour cherry (Prunus cerasus) in Russia. They failed to be recognized by RT-PCR using commonly employed primers specific to the strains C or CR (the only ones that proved able to infect sour cherry) as well as to the strains M and W. Some of them can be detected by RT-PCR using the PPV-D-specific primers P1/PD or by TAS-ELISA with the PPV-C-specific monoclonal antibody AC.

High-precision force sensing using a single trapped ion.

We introduce quantum sensing schemes for measuring very weak forces with a single trapped ion. They use the spin-motional coupling induced by the laser-ion interaction to transfer the relevant force information to the spin-degree of freedom. Therefore, the force estimation is carried out simply by observing the Ramsey-type oscillations of the ion spin states.

Occurrence and characterization of plum pox virus strain D isolates from European Russia and Crimea.

Numerous plum pox virus (PPV) strain D isolates have been found in geographically distant regions of European Russia and the Crimean peninsula on different stone fruit hosts. Phylogenetic analysis of their partial and complete genomes suggests multiple introductions of PPV-D into Russia. Distinct natural isolates from Prunus tomentosa were found to bear unique amino acid substitutions in the N-terminus of the coat protein (CP) that may contribute to the adaptation of PPV-D to this host.

High-level systemic expression of conserved influenza epitope in plants on the surface of rod-shaped chimeric particles.

Recombinant viruses based on the cDNA copy of the tobacco mosaic virus (TMV) genome carrying different versions of the conserved M2e epitope from influenza virus A cloned into the coat protein (CP) gene were obtained and partially characterized by our group previously; cysteines in the human consensus M2e sequence were changed to serine residues. This work intends to show some biological properties of these viruses following plant infections. Agroinfiltration experiments on Nicotiana benthamiana confirmed the efficient systemic expression of M2e peptides, and two point amino acid substitutions in recombinant CPs significantly influenced the symptoms and development of viral infections.