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The algebra of GLn-invariants of m-tuples of n × n matrices with respect to the action by simultaneous conjugation is a classical topic in case of infinite base field. On the other hand, in case of a finite field generators of polynomial invariants are not known even for a pair of 2 × 2 matrices. Working over an arbitrary field we classified all GL2-orbits on m-tuples of 2 × 2 nilpotent matrices for all m > 0. As a consequence, we obtained a minimal separating set for the algebra of GL2-invariant polynomial functions of m-tuples of 2 × 2 nilpotent matrices. We also described the least possible number of elements of a separating set for an algebra of invariant polynomial functions over a finite field. [ABSTRACT FROM AUTHOR]

Rationale: Ceria‐based systems are of great interest because of their unique properties. Such systems may be used as anode materials for SOFCs or in oxygen sensors. The exploitation of these materials often requires high temperatures. In such conditions, the partial or complete evaporation of materials is possible. Therefore, knowledge of the values of partial pressures and thermodynamic properties is essential to predict and/or prevent possible consequences and accidents. Methods: Knudsen effusion mass spectrometry was used to determine partial pressures of vapor species over the SrO–CeO2 and CaO‐CeO2 systems. Measurements of partial pressures were performed with a MS‐1301 mass spectrometer. Vaporization was carried out using molybdenum or tungsten effusion cells. A theoretical study of gaseous strontium and calcium cerates was performed by several quantum chemical methods: density functional theory (DFT) M06, DFT PBE0, and MP2. Results: The minimum value of relative electron ionization cross‐section for CeO2 was estimated. In the temperature range of 2218–2249 K above the SrO‐CeO2 system and of 2128–2208 K above the CaO‐CeO2 system, gaseous M, MO, MO, CeO2, O, O2 and MCeO3 (M = Sr, Ca) were found. Energetically favorable structures of gaseous SrCeO3 and CaCeO3 were found, and vibrational frequencies were evaluated in the "rigid rotor‐harmonic oscillator" approximation. On the basis of the equilibrium constants of gaseous reaction MO + CeO2 = MCeO3, the standard formation enthalpy of gaseous SrCeO3 (−913 ± 26 kJ/mol) and of gaseous CaCeO3 (−917 ± 26 kJ/mol) at 298 K were determined. Conclusions: The estimated value of relative electron ionization cross‐section for CeO2 is in agreement with the general rule applicable for dioxides. The stability of SrCeO3 and CaCeO3 gaseous species was confirmed by KEMS. Gas‐phase reactions involving gaseous SrO (CaO) and CeO2 with gaseous SrCeO3(CaCeO3) were studied. Enthalpy of formation reaction of gaseous SrCeO3(CaCeO3) from gaseous SrO (CaO) were evaluated theoretically, and the obtained value is in agreement with the experimental one. [ABSTRACT FROM AUTHOR]

Takotsubo syndrome (TTS) still remains as an enigmatic phenomenon. In particular, long-term challenges (including clinical recurrence and persistent symptoms) and specific entities in the setting of TTS have been the evolving areas of interest. On the other hand, a significant gap still exists regarding the proper risk-stratification of this phenomenon in the short and long terms. The present paper, the second part (part-2) of the consensus report, aims to discuss less well-known aspects of TTS including specific entities, challenges after recovery and risk-stratification. [ABSTRACT FROM AUTHOR]

In the recent years, there has been a burgeoning interest in Takotsubo syndrome (TTS), which is renowned as a specific form of reversible myocardial dysfunction. Despite the extensive literature available on TTS, clinicians still face several practical challenges associated with the diagnosis and management of this phenomenon. This potentially results in the underdiagnosis and improper management of TTS in clinical practice. The present paper, the first part (part-1) of the consensus report, aims to cover diagnostic and therapeutic challenges associated with TTS along with certain recommendations to combat these challenges. [ABSTRACT FROM AUTHOR]

A fragmentary maxilla and isolated vertebrae of a viperid snake were found in the Lower Pleistocene deposits of the Taurida cave, Crimean Peninsula. The snake is assigned to Vipera cf. renardi based on the morphology of the maxilla. This is the first unquestionable fossil record of the Vipera ursinii-renardi complex dispersed into Crimea earlier than previously supposed, already in the Early Pleistocene. [ABSTRACT FROM AUTHOR]

Aims: Reverse ventricular remodelling, defined as a decrease in left ventricular end‐systolic volume indexed to body surface area (LVESVI) or an increase in left ventricular ejection fraction (LVEF), is associated with improved clinical outcomes in patients with heart failure with reduced ejection fraction (HFrEF). However, the underlying pathophysiological mechanisms remain unclear. Methods and results: We evaluated paired core‐lab assessed echocardiograms and measurements of 92 biomarkers at baseline and 8 months thereafter in 419 participants with HFrEF. Reverse ventricular remodelling was defined as a >5% LVEF increase or >15% LVESVI relative decrease between baseline and 8 months. We evaluated the association between baseline biomarkers and their changes with reverse ventricular remodelling in the prospectively randomized controlled VICTORIA (Vericiguat Global Study in Subjects With Heart Failure With Reduced Ejection Fraction) trial. Of 419 patients (median age 66 [interquartile range 57–74] years, 27.4% women), 206 (49.2%) had reverse ventricular remodelling (either a 5% LVEF increase or a 15% LVESVI decrease). There were no differences in baseline biomarker concentrations between patients with versus those without reverse ventricular remodelling on follow‐up. However, in patients with reverse ventricular remodelling there were significant decreases in biomarkers relating to inflammation and cardiac metabolism; particularly the tumour necrosis factor superfamily member 13B (ratio 0.82, 95% confidence interval [CI] 0.77–0.88), growth differentiation factor‐15 (ratio 0.74, 95% CI 0.66–0.84), and insulin‐like growth factor binding protein 7 (ratio 0.80, 95% CI 0.73–0.88). Conclusions: Reverse ventricular remodelling in patients with HFrEF is associated with a decrease of biomarkers related to inflammation and cardiac metabolism. [ABSTRACT FROM AUTHOR]

The versatile Generalized Retrieval of Aerosol and Surface Properties (GRASP) algorithm exploits the advantages of synergic ground-based aerosol observations such as radiometric (sensitive to columnar aerosol optical and microphysical properties) and lidar (sensitive to vertical distribution of the optical properties) observations. The synergy is possible when the complementary data is mutually constrained by GRASP parametrization that includes, for the first time ever, the degree of linear polarization (DoLP) parameter measured by a polarized sun-sky-lunar AERONET photometer (380, 440, 500, 675, 870, 1020, and 1640 nm) in synergy with the vertical profiles from an elastic lidar (355, 532, and 1064 nm). First, a series of numerical tests is performed using simulated data generated using a climatology of data and ground-based measurements. The inversions are performed with and without random noise for five different combinations of input data, starting from the AERONET-like dataset and increasing to the complex one by adding more information for three aerosol scenarios: I—high aerosol optical depth (AOD) with dominant coarse mode; II—low AOD with dominant coarse mode; III—high AOD with dominant fine mode. The inclusion of DoLP improves (i) the retrieval accuracy of the fine-mode properties when it is not dominant; (ii) the retrieval accuracy of the coarse-mode properties at longer wavelengths and that of the fine-mode properties at shorter wavelengths; (iii) the retrieval accuracy of the coarse-mode real part of the refractive index (up to 36% reduction), but has no effect on the retrieval of the imaginary part; (iv) reduces up to 83% the bias of the sphere fraction (SF) retrieval in coarse-mode dominated regimes; and (v) the root mean square error (RMSE) of the retrieval for most of the parameters in all scenarios. In addition, the addition of more photometer channels in synergy with a three-wavelength elastic lidar reduces the RMSE for the real part (67% in the coarse mode) and the imaginary part (35% in the fine mode) of the refractive index, the single scattering albedo (38% in the fine mode), the lidar ratio (20% in the coarse mode), and the SF (43%).

Aim. Study the impact of various combinations of comorbid original diseases in patients infected with COVID-19 later on the disease progression and outcomes of the new coronavirus infection. Materials and methods. The ACTIV registry was created on the Eurasian Association of Therapists initiative. 5,808 patients have been included in the registry: men and women with COVID-19 treated at hospital or at home. ClinicalTrials.gov ID NCT04492384. Results. Most patients with COVID-19 have original comorbid diseases (oCDs). Polymorbidity assessed by way of simple counting of oCDs is an independent factor in negative outcomes of COVID-19. Search for most frequent combinations of 2, 3 and 4 oCDs has revealed absolute domination of cardiovascular diseases (all possible variants). The most unfavorable combination of 2 oCDs includes atrial hypertension (AH) and chronic heart failure (CHF). The most unfavorable combination of 3 oCDs includes AH, coronary heart disease (CHD) and CHF; the worst combination of 4 oCDs includes AH, CHD, CHF and diabetes mellitus. Such combinations increased the risk of lethal outcomes 3.963, 4.082 and 4.215 times respectively. Conclusion. Polymorbidity determined by way of simple counting of diseases may be estimated as a factor in the lethal outcome risk in the acute phase of COVID-19 in real practice. Most frequent combinations of 2, 3 and 4 diseases in patients with COVID-19 primarily include cardiovascular diseases (AH, CHD and CHF), diabetes mellitus and obesity. Combinations of such diseases increase the COVID-19 lethal outcome risk.

Aim. To investigate on post-COVID period in patients of the Eurasian region.Material and methods. A total of 9364 consecutively hospitalized patients were included in ACTIV registry. Enrollment of patients began on June 29, 2020, and was completed on March 30, 2021, corresponding to the first and second waves of the pandemic. Demographic, clinical, and laboratory data, computed tomography (CT) results, information about inhospital clinical course and complications of COVID-19 during hospitalization were extracted from electronic health records using a standardized data collection form. The design included follow-up telephone interviews with a standard questionnaire at 3, 6, and 12 months to examine the course of post-COVID period.Results. According to ACTIV register, 63% of patients after COVID-19 had new adverse symptoms or exacerbations of the existing symptoms lasting for up to 1 year. After hospital discharge, 79,8% of patients sought unscheduled medical attention in the first 3 months, 79,1% at 4-6 months, and 64,8% at 7-12 months. Readmission rate was 11,8% in the first 3 months, 10,9% at 4-6 months, and 10,1% at 7-12 months. The most common reasons for unscheduled treatment in the first 3 months were uncontrolled hypertension, decompensated type 2 diabetes, destabilization of coronary artery disease, gastrointestinal disease, AF episodes, exacerbation of asthma and chronic obstructive pulmonary disease, decompensated heart failure (HF). The 12-month mortality of COVID-19 survivors after the discharge was 3,08%. Multivariate analysis showed that independent risk factors for fatal outcome were age (direct correlation), the levels of hemoglobin (inverse correlation), oxygen saturation (inverse correlation), and aspartate aminotransferase (direct correlation), as well as class III-IV HF, prior stroke, cancer, inhospital acute kidney injury. Based on these identified risk factors, a nomogram was constructed to determine the 3-month mortality risk after discharge.Conclusion. Analysis of ACTIV register showed that end of the acute phase of COVID-19 does not imply a complete recovery.

Abstract Cardiogenic shock (CS) is a complex multifactorial clinical syndrome, developing as a continuum, and progressing from the initial insult (underlying cause) to the subsequent occurrence of organ failure and death. There is a large phenotypic variability in CS, as a result of the diverse aetiologies, pathogenetic mechanisms, haemodynamics, and stages of severity. Although early revascularization remains the most important intervention for CS in settings of acute myocardial infarction, the administration of timely and effective antithrombotic therapy is critical to improving outcomes in these patients. In addition, other clinical settings or non‐acute myocardial infarction aetiologies, associated with high thrombotic risk, may require specific regimens of short‐term or long‐term antithrombotic therapy. In CS, altered tissue perfusion, inflammation, and multi‐organ dysfunction induce unpredictable alterations to antithrombotic drugs' pharmacokinetics and pharmacodynamics. Other interventions used in the management of CS, such as mechanical circulatory support, renal replacement therapies, or targeted temperature management, influence both thrombotic and bleeding risks and may require specific antithrombotic strategies. In order to optimize safety and efficacy of these therapies in CS, antithrombotic management should be more adapted to CS clinical scenario or specific device, with individualized antithrombotic regimens in terms of type of treatment, dose, and duration. In addition, patients with CS require a close and appropriate monitoring of antithrombotic therapies to safely balance the increased risk of bleeding and thrombosis.

Background. High-dose implantation of cobalt ions into the crystal structure of natural colourless quartz was carried out. Samples of crystal plates of rock crystal from the Svetlinskoye deposit in the South Urals plane-parallel were studied. All samples were crystallographically oriented perpendicular to the symmetry axis of the third order. Cobalt implantation into quartz was carried out using an ILU-3 ion-beam accelerator along the С axis of symmetry.Aim. To determine the ranges of thermal annealing for a controlled change in the sample colour and to establish the crystal-chemical features of the changes occurring in quartz matrix due to ionbeam modification of mineral properties.Materials and methods. Implantation modes included: room temperature, residual vacuum 10–5 torr, radiation dose from 1.0×1017 to 1.5×1017 ion/cm2 at a constant ion current density of 10 μA/cm2. Post-implantation heat treatment was carried out in three stages. The control of crystallochemical changes was carried out using a highly sensitive spectrophotometer with a wide range of wavelengths.Results. It was found that the revealed absorption bands are associated with electronic transitions in cobalt ions (Со2+ and Со 3+) coordinated in the crystal matrix of implanted and heat-treated rock crystal. The formation of an independent ultradispersed spinel phase in the irradiated quartz matrix was confirmed. The newly formed phase belongs to a partially reversed cobalt spinel.Conclusions. Taking into account the quantum-optical properties of cobalt spinel (laser shutters), the method of ion-beam modification of mineral crystal structures, quartz in particular, is highly promising in terms of creating new composite materials based on natural and artificial mineral raw materials.