All-dielectric magnetic metasurface for advanced light control in dual polarizations combined with high-Q resonances

Nanostructured magnetic materials provide an efficient tool for light manipulation on sub-nanosecond and sub-micron scales, and allow for the observation of the novel effects which are fundamentally impossible in smooth films. For many cases of practical importance, it is vital to observe the magneto-optical intensity modulation in a dual-polarization regime. However, the nanostructures reported on up to date usually utilize a transverse Kerr effect and thus provide light modulation only for p-polarized light. We present a concept of a transparent magnetic metasurface to solve this problem, and demonstrate a novel mechanism for magneto-optical modulation. A 2D array of bismuth-substituted iron-garnet nanopillars on an ultrathin iron-garnet slab forms a metasurface supporting quasi-waveguide mode excitation. In contrast to plasmonic structures, the all-dielectric magnetic metasurface is shown to exhibit much higher transparency and superior quality-factor resonances, followed by a multifold increase in light intensity modulation. The existence of a wide variety of excited mode types allows for advanced light control: transmittance of both p- and s-polarized illumination becomes sensitive to the medium magnetization, something that is fundamentally impossible in smooth magnetic films. The proposed metasurface is very promising for sensing, magnetometry and light modulation applications

Development of polyresistance in microorganisms during antibiotic therapy in a multidisciplinary hospital during a pandemic COVID-19

Background. Irrational and excessive use of antimicrobials drugs (AMD) creates conditions for the development of a global crisis of health systems around the world associated with antibiotic resistance. Aim. To conduct a retrospective study of the impact of the use of AMD on the change in the microbiological landscape and the sensitivity of microorganisms in the conditions of pandemic of the new coronavirus infection (COVID-19) in 2020–2021 in intensive care departments (ICD) of a multidisciplinary hospital. Materials and methods. In the course of the work, strains of microorganisms isolated from patients and from the surfaces of the hospital environment and changes in their sensitivity to significant groups of AMD in ICD for somatic and infectious patients with COVID-19 were compared. The sensitivity of the isolates was evaluated in accordance with the criteria of requirements of European Committee on Antimicrobial Susceptibility Testing – EUCAST, version 10.0, 2020. Results. A total of 1,394 isolates were studied, including 1,379 clinical and 15 isolates from the surfaces of the hospital environment. It was found that in all ICD in 2020–2021, gram-negative microorganisms prevailed in infectious loci in 70% of cases or more. In 2021, in the ICD in infectious patients with COVID-19, the persistent dominance of the Acinetobacter baumannii microorganism was revealed with an increase in the number of poly- and pan-resistant strains – 48.7%. While in the ICD for somatic patients Klebsiella Pneumoniae prevailed among gram-negative microorganisms – 37.5% in 2020 and 43.7% in 2021. It has been shown that in one department or in adjacent departments of the same medical institution, various nosocomial microorganisms with an unequal set of resistance genes and sensitivity to AMD may appear over time. Conclusion. The necessity of conducting constant microbiological monitoring and a passport of the medical department with mandatory registration of not only isolated strains of microorganisms, but also resistance genes in order to optimize the appointment of timely adequate empirical antimicrobial therapy is substantiated. The period of the latter should be as short as possible, and confirmed by convincing clinical signs of bacterial infection, and subsequently by the isolation of nosocomial flora from the biomaterial of critical loci from patients

The LHCb upgrade I

The LHCb upgrade represents a major change of the experiment. The detectors have been almost completely renewed to allow running at an instantaneous luminosity five times larger than that of the previous running periods. Readout of all detectors into an all-software trigger is central to the new design, facilitating the reconstruction of events at the maximum LHC interaction rate, and their selection in real time. The experiment's tracking system has been completely upgraded with a new pixel vertex detector, a silicon tracker upstream of the dipole magnet and three scintillating fibre tracking stations downstream of the magnet. The whole photon detection system of the RICH detectors has been renewed and the readout electronics of the calorimeter and muon systems have been fully overhauled. The first stage of the all-software trigger is implemented on a GPU farm. The output of the trigger provides a combination of totally reconstructed physics objects, such as tracks and vertices, ready for final analysis, and of entire events which need further offline reprocessing. This scheme required a complete revision of the computing model and rewriting of the experiment's software

Searches for low-mass dimuon resonances

Abstract: Searches are performed for a low-mass dimuon resonance, X, produced in proton-proton collisions at a center-of-mass energy of 13 TeV, using a data sample corresponding to an integrated luminosity of 5.1 fb−1 and collected with the LHCb detector. The X bosons can either decay promptly or displaced from the proton-proton collision, where in both cases the requirements placed on the event and the assumptions made about the production mechanisms are kept as minimal as possible. The searches for promptly decaying X bosons explore the mass range from near the dimuon threshold up to 60 GeV, with nonnegligible X widths considered above 20 GeV. The searches for displaced X → μ+μ− decays consider masses up to 3 GeV. None of the searches finds evidence for a signal and 90% confidence-level exclusion limits are placed on the X → μ+μ− cross sections, each with minimal model dependence. In addition, these results are used to place world-leading constraints on GeV-scale bosons in the two-Higgs-doublet and hidden-valley scenarios

The Main Elements of Development of Mandatory Access Control Mechanism in DBMS MySQL based on DP-Models

It is proposed an approach to development of mandatory access control in originally discrete DBMS MySQL based on DP-models. It is performed analysis of the existent access control mechanisms in this DBMS, it is described DP-model of MySQL, and it is implemented mandatory access control mechanism based on this model

Investigation of algorithms for suppressing xenon oscillations in a VVER-1200 reactor

This paper presents the results of numerical studies of various algorithms for suppression of xenon offset and power distribution oscillations in the core of a VVER-1200 reactor. The purpose of the research is to select an algorithm that minimizes the amount of liquid radioactive wastes during water exchange in the primary circuit of a nuclear power plant. For this, several algorithms for xenon oscillations suppression were considered. The first algorithm considered was an algorithm for suppression of xenon oscillations, which uses regulation due to AWP only, without utilization of any additional regulation. The second algorithm considered was an algorithm based on the use both AWP and boron regulation. In this algorithm suppression of xenon oscillations was carried out with the help of accelerated initiation of the work of the AWP by changing the boric acid concentration with constant second circuit pressure of the NPP and by utilization of the second control rods group. Last algorithm considered was algorithm based on the use of temperature control for accelerated initiation of the work of the AWP. In this algorithm, xenon oscillations suppression was carried out by changing coolant temperature at the reactor inlet caused by pressure change in the secondary circuit in the normal operation margins, and by involving the second group of control rods. It was shown that the best way to suppress xenon offset and power distribution oscillations in terms of minimization of radioactive liquid wastes amount is the algorithm with accelerated initiation of the AWP due to temperature regulation, with elimination of temperature regulation after minimizing of current axial offset value deviation from the nominal one

Experimental Study of Class E Family Power Amplifiers with Shunt Filter for Reduced Duty Ratio

This work presents an experimental investigation of class E power amplifier with parallel shunt network along with two similar amplifier obtained by adding series-connected parallel resonant tanks tuned for the second (class E/F3) and the third harmonics with duty ratio of D=0.33. The aim was obtaining of decreasing of maximum drain-source voltage together with high efficiency remaining. The experimental results shown about 0.6 W output power with 80% efficiency and reducing of drain-source voltage up to 2.5 times of voltage supply

Unusual Case of Anaplastic Large Cell Lymphoma Presenting as a Breast Mass in a Patient with no History of Breast Implants

Adenocarcinoma is the most common malignant neoplasm involving breast tissue. In contrast to carcinomas, the other types of malignant neoplasms involving the breast are relatively uncommon. One of the examples of this rare entity is lymphoma. Traditionally, non-Hodgkin lymphomas (NHL) involving the breast are divided into primary lymphoma of the breast and systemic lymphoma, although the distinction could be challenging. Most of NHL involving breast tissue have B cell origin; T cell NHL represents less than 20% of all lymphoma cases. Anaplastic large cell lymphomas (ALCL) involving the breast accounts for even lower percentage of cases. Similar to ALCL involving other sites, there are several main types of ALCL identified: primary cutaneous ALCL and systemic ALCL, which is subdivided into ALK positive and ALK negative subtypes. Relatively recently, an additional distinct subtype of ALK-negative ALCL was described, which is associated with textured breast implants and needs to be considered as a differential diagnosis if patient has a history of breast implants. Here, we report a case of ALCL presented as a breast mass without history of breast implant and discuss similar cases published in the literature