Geometric phase and o-mode blue shift in a chiral anisotropic medium inside a Fabry-P\'erot cavity

Anomalous spectral shift of transmission peaks is observed in a Fabry--P\'erot cavity filled with a chiral anisotropic medium. The effective refractive index value resides out of the interval between the ordinary and the extraordinary refractive indices. The spectral shift is explained by contribution of a geometric phase. The problem is solved analytically using the approximate Jones matrix method, numerically using the accurate Berreman method and geometrically using the generalized Mauguin--Poincar\'e rolling cone method. The $o$-mode blue shift is measured for a 4-methoxybenzylidene-4'-$n$-butylaniline twisted--nematic layer inside the Fabry--P\'erot cavity. The twist is electrically induced due to the homeoplanar--twisted configuration transition in an ionic-surfactant-doped liquid crystal layer. Experimental evidence confirms the validity of the theoretical model.Comment: the text is available both in English (Timofeev2015en.tex) and in Russian (download: other formats - source - Timofeev2015ru.tex, Timofeev2015rus.pdf

Plasma probe characteristics in low density hydrogen pulsed plasmas

Probe theories are only applicable in the regime where the probe's perturbation of the plasma can be neglected. However, it is not always possible to know, a priori, that a particular probe theory can be successfully applied, especially in low density plasmas. This is especially difficult in the case of transient, low density plasmas. Here, we applied probe diagnostics in combination with a 2D particle-in-cell model, to an experiment with a pulsed low density hydrogen plasma. The calculations took into account the full chamber geometry, including the plasma probe as an electrode in the chamber. It was found that the simulations reproduce the time evolution of the probe IV characteristics with good accuracy. The disagreement between the simulated and probe measured plasma density is attributed to the limited applicability of probe theory to measurements of low density pulsed plasmas. Indeed, in the case studied here, probe measurements would lead to a large overestimate of the plasma density. In contrast, the simulations of the plasma evolution and the probe characteristics do not suffer from such strict applicability limits. These studies show that probe theory cannot be justified through probe measurements

Experimental observation of spontaneous spin polarization of electrons in hybridized states of transition element impurities in semiconductors

Experimental evidence of the possible existence of spontaneous spin polarization of the electron system in hybridized states formed by transition element impurity atoms in the conduction band of semiconducting crystals is examined. The details of a quantitative interpretation of experiments on the temperature dependence of the specific heat and elastic moduli of mercury selenide crystals with iron impurities confirm the feasibility of establishing the presence of electron spin polarization in this type of experiment, as well as the possible existence of polarization in the crystals studied here. Theoretical arguments support the observation of a thermodynamic anomalous Hall effect owing to spontaneously polarized donor electrons from low-concentration impurities. © 2013 AIP Publishing LLC

Generics and biosimilars in oncology

Cancer-related morbidity and mortality have been increasing worldwide including in Russia. In recent decades, many innovative antineoplastic pharma products have been launched in the international pharmaceutical market; however, their high price has resulted in significant increase in the cost of treatment and in its inaccessibility for a considerable percentage of patients not only in the countries experiencing low economic growth, but also in those with a high level of economic development. One of the most effective ways of reducing the cost of pharmacotherapy is replacement of innovation medications after the expiration of the patent with their generics and biosimilars. In this article the authors discuss the cost of oncopathology pharmacotherapy with original drugs and their generics and also the factors that affect cost-effectiveness of generics and biosimilars in oncology

Methodological Approaches to Studying Fatal Adverse Drug Reactions

Serious adverse drug reactions (ADRs) to medicinal products can cause death. It is an immediate challenge for modern medicine to prevent the possibility of this outcome and to improve the safety of pharmacotherapy. The aim of this study was to identify and analyse the main methodological approaches to studying the prevalence, patterns, and risk factors of fatal ADRs. The authors identified three main methods for studying such reactions: analysis of death certificates, monitoring of spontaneous reports, and review of clinical trials with a particular focus on safety. Each of these methods has its advantages and limitations. Clinical trials provide the most accurate information on the prevalence of fatal ADRs. For inpatients, this value ranged from 0.05 to 0.95% of the total number of hospital admissions. Data from death certificates may be particularly useful for identifying the groups of medicinal products posing a high risk of death and for making longitudinal comparisons. Monitoring of spontaneous reports is very effective in rapidly identifying fatal adverse reactions to new medicinal products. According to the authors, not only the choice of a data collection method, but also its application can affect the results of an ADR study. It was noted that the data varied across clinical trials conducted in different countries. Such variations indicate the importance of studying the problem of fatal ADRs at the national level, as well as the need for initiating such studies in the Russian Federation

harmacoeconomic feasibility of using the drug upadacitinib in patients with rheumatoid arthritis in the healthcare system of the Russian Federation

Aim. To assess the pharmacoeconomic feasibility of including the drug upadacitinib in restrictive lists and government funding programs to provide patients with rheumatoid arthritis.Materials and methods. Study Design — Retrospective Analysisof Literary Data. Pharmacoeconomic analysis methods — indirect comparison, clinical-economic analysis (cost-effectiveness analysis) using sensitivity analysis; budget impact analysis using sensitivity analysis. Data on the effectiveness of the analyzed drugs are taken from publications on clinical studies of the compared drugs; on the cost of drugs — the state register of marginal selling prices, data of the manufacturer’s company.Results. According to the results of indirect comparison, with respect to the frequency of achievement of the DAS28 test (CRP) <2.6, the effectiveness of the preparations tofacitinib and baricitinib does not significantly differ — OR = 1.275 (0.842; 1.931). At the same time, the preparation upadacitinib allows to achieve this indicator reliably more effective than the baricitinib — OR = 1.529 (1.021; 2.292) and tofacitinib — OR = 1.95 (1.285; 2.960). Costs for the use of upadacitinib against the background of methotrexate for 52 weeks will amount to 654 983.88 rubles, and will require 4.7 % less costs than the use of tofacitinib or baricitinib against the background of the use of methotrexate (687 217.53 rubles). In an indirect comparison of upadacitinib-baricitinib through the general comparator adalimumab, the effectiveness of upadacitinib with respect to the frequency of achievement of DAS28-CRP <2.6 turned out to be higher than baricitinib per 32.3 %. With indirect comparison of upadacitinib-tofacitinib under the same conditions, the efficiency of upadacitinib is 57.7 % higher than that of tofacitinib. Analysis of the impact on the budget showed that with the inclusion of the drug upadacitinib in the lists of VED and ONLS and a gradual increase in the proportion of patients, receiving upadacitinib instead of tofacitinib and baricitinib in the 1st year before 15 %, in the 2nd year — 30 %, in the 3rd year — 45 % for the group of 2.318 patients for 3 years, the reduction in the budget burden will be 1.4 % or 62.8 million rubles. With the provision of upadacitinib, 100 % of patients from the first year, the budget burden for 3 years will decrease by 4.7 % or 213.1 million rubles in comparison with the current regime.Conclusion. tte drug upadacitinib at a lower course cost has greater effectiveness in achieving clinical remission according to the indicator DAS28-CRP (<2.6), and therefore its use in the conditions of the healthcare system of the Russian Federation for the treatment of patients with rheumatoid arthritis is pharmacoeconomic and expedient

Clinical and pharmacoeconomic aspects of anti-TNF therapy change for medical reasons

The substitution of one drug for another within one class can be caused by both medical indications, such as low therapeutic efficacy, and by non-medical factors, for example, by choosing a less expensive drug. In this article, the available data on the impact of non-medical switching on the clinical and pharmacoeconomic indices of anti-TNF therapy with drugs are considered

Effect of Fermi-liquid interactions on the low-temperature de Haas - van Alphen oscillations in quasi-two-dimensional conductors

In this work we present the results of theoretical analysis of the de Haas-van Alphen oscillations in quasi-two-dimensional conductors. We have been studying the effect of the Fermi-liquid correlations of charge carriers on the above oscillations. It was shown that at reasonably low temperatures and weak electron scattering the Fermi-liquid interactions may cause noticeable changes in both amplitude and shape of the oscillations even at realistically small values of the Fermi-liquid parameters. Also, we show that the Fermi-liquid interactions in the system of the charge carriers may cause magnetic instability of a quasi-two-dimensional conductor near the peaks of quantum oscillations in the electron density of states at the Fermi surface, indicating the possibility for the diamagnetic phase transition within the relevant ranges of the applied magnetic fields.Comment: 10 pages, 4 figure

Synthesis of Pah-Containing Copolymers on the Basis of Acrylic Acid

This work was funded by Russian Science Foundation (Ref no. 18-73-00301)

Analysis of the infectious agent’s structure and antibiotic resistance parameters in patients in intensive care units of a multidisciplinary hospital

Introduction.  Nosocomial infections are a common complication in patients treated in the intensive care unit (ICU). Microorganisms with multidrug resistance are one of the significant risk factors for death in this category of patients. Aim. To study structure of infectious agents in ICU patients and parameters of their antibiotic resistance.  Materials and methods. Retrospective pharmacoepidemiological study of medical records of adult patients with infections diagnosed in ICU who were treated in City Clinical Hospital No. 24 of the Department of Health (Moscow, Russian Federation) in the period 08/20/2022 — 07/31/2023 (n=199). The analysis (gender, age of patients, localization of the infectious process, data on the structure of pathogens and sensitivity to antibacterial drugs) included records with data on bacterial culture ( n=141). Results. In the structure of pathogens detected in ICU patients, gram-negative microflora predominated (54 %). Among the pathogens with a clinically significant growth, leaders were  K. pneumoniae (22 %), Candida spp. (20 %) and  Staphylococcus  spp. (19 %). K. pneumoniae was characterized by resistance to beta-lactams, aminoglycosides, and levofloxacin, the highest susceptibility was reported to colistin, 88.9 %.  Candida  spp. was overwhelmingly susceptible to all drugs used. Among Staphylococ caceae, S. aureus  was the most common (70 % resistance to ampicillin and cefoxitin).  Conclusion.  In the structure of infectious agents detected in ICU patients, a predominance of ESKAPE pathogens (the most prognostically important microorganisms: Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter spp.) was observed, including K. pneumoniae, S. aureus, A. baumannii, P. aeruginosa.  For all these microorganisms, except for Staphylococcaceae, a high level of antibiotic resistance was demonstrated