Publications by authors named "Kurnosov A"

Objective: To evaluate the effectiveness of leukocyte, NLR, procalcitonin and C-reactive protein as the markers of acute peritonitis in patients with HIV-infection.

Material And Methods: The study included 83 HIV-infected patients with various diseases complicated by acute peritonitis. Leukocytes, procalcitonin and C-reactive protein, as well as immune status and viral load were determined in peripheral blood before surgery.

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Recent experimental developments in multimode nonlinear photonic circuits (MMNPCs), have motivated the development of an optical thermodynamic theory that describes the equilibrium properties of an initial beam excitation. However, a nonequilibrium transport theory for these systems, when they are in contact with thermal reservoirs, is still terra incognita. Here, by combining Landauer and kinematics formalisms we develop a universal one-parameter scaling theory that describes the whole transport behavior from the ballistic to the diffusive regime, including both positive and negative optical temperature scenarios.

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Article Synopsis
  • Iron shows promise as a non-toxic energy carrier for long-term energy storage, but detailed knowledge of its oxidation kinetics for micrometer-sized particles is limited.
  • This study uses temperature-programmed oxidation and boron nitride dilution to prevent sintering, allowing investigation of individual particle behavior during oxidation.
  • Findings reveal that iron oxidation follows a parabolic rate law, with key data on phase compositions and rate constants obtained, emphasizing the importance of particle size distribution in modeling oxidation kinetics.
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The molecular events underlying the development, manifestation, and course of schizophrenia, bipolar disorder, and major depressive disorder span from embryonic life to advanced age. However, little is known about the early dynamics of gene expression in these disorders due to their relatively late manifestation. To address this, we conducted a secondary analysis of post-mortem prefrontal cortex datasets using bioinformatics and machine learning techniques to identify differentially expressed gene modules associated with aging and the diseases, determine their time-perturbation points, and assess enrichment with expression quantitative trait loci (eQTL) genes.

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Non-alcoholic fatty liver disease (NAFLD) is considered the most common chronic liver disease worldwide, affecting nearly 25% of the global adult population. Increasing evidence suggests that functional and compositional changes in the gut microbiota may contribute to the development and promote the progression of NAFLD. 16S rRNA gene next-generation sequencing is widely used to determine specific features of the NAFLD microbiome, but a complex system such as the gut microbiota requires a comprehensive approach.

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Glasses, unlike crystals, are intrinsically brittle due to the absence of microstructure-controlled toughening, creating fundamental constraints for their technological applications. Consequently, strategies for toughening glasses without compromising their other advantageous properties have been long sought after but elusive. Here we report exceptional toughening in oxide glasses via paracrystallization, using aluminosilicate glass as an example.

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Developing biodegradable materials based on polymer blends with a programmable self-destruction period in the environmental conditions of living systems is a promising direction in polymer chemistry. In this work, novel non-woven fibrous materials obtained by electrospinning based on the blends of poly(lactic acid) (PLA) and poly(3-hydroxybutyrate) (PHB) were developed. The kinetics of biodegradation was studied in the aquatic environment of the inoculum of soil microorganisms.

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The metal-insulator transition driven by electronic correlations is one of the most fundamental concepts in condensed matter. In mixed-valence compounds, this transition is often accompanied by charge ordering (CO), resulting in the emergence of complex phases and unusual behaviors. The famous example is the archetypal mixed-valence mineral magnetite, FeO, exhibiting a complex charge-ordering below the Verwey transition, whose nature has been a subject of long-time debates.

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The success of high-pressure research relies on the inventive design of pressure-generating instruments and materials used for their construction. In this study, the anvils of conical frustum or disk shapes with flat or modified culet profiles (toroidal or beveled) were prepared by milling an Ia-type diamond plate made of a (100)-oriented single crystal using the focused ion beam. Raman spectroscopy and synchrotron x-ray diffraction were applied to evaluate the efficiency of the anvils for pressure multiplication in different modes of operation: as single indenters forced against the primary anvil in diamond anvil cells (DACs) or as pairs of anvils forced together in double-stage DACs (dsDACs).

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Cubic CaSiO perovskite is a major phase in subducted oceanic crust, where it forms at a depth of about 550 kilometres from majoritic garnet. However, its rheological properties at temperatures and pressures typical of the lower mantle are poorly known. Here we measured the plastic strength of cubic CaSiO perovskite at pressure and temperature conditions typical for a subducting slab up to a depth of about 1,200 kilometres.

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The phenomenon of host-guest hydrogen bonding in clathrate hydrate crystal structures and its effect on physical and chemical properties have become subjects of extensive research. Hydrogen bonding has been studied for cubic (sI and sII) and hexagonal (sH) binary clathrates, while it has not been addressed for clathrate structures that exist at elevated pressures. Here, four acetone hydrate clathrates have been grown at high-pressure and low-temperature conditions.

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The numerical modelling of magma transport and volcanic eruptions requires accurate knowledge of the viscosity of magmatic liquids as a function of temperature and melt composition. However, there is growing evidence that volcanic melts can be prone to nanoscale modification and crystallization before and during viscosity measurements. This challenges the possibility of being able to quantify the crystal-free melt phase contribution to the measured viscosity.

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Ultrathin fibrous materials based on natural bacterial polymer polyhydroxybutyrate (PHB) were prepared by the electrospinning method. Using scanning electron and optical microscopy techniques the macrophysical characteristics of the fibrous layer were determined and classified. The physicomechanical characteristics of the resultant materials and their changes caused by ozonation were determined as well.

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Ultrathin electrospun fibers of pristine biopolyesters, poly(3-hydroxybutyrate) (PHB) and polylactic acid (PLA), as well as their blends, have been obtained and then explored after exposure to hydrolytic (phosphate buffer) and oxidative (ozone) media. All the fibers were obtained from a co-solvent, chloroform, by solution-mode electrospinning. The structure, morphology, and segmental dynamic behavior of the fibers have been determined by optical microscopy, SEM, ESR, and others.

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A resistively-heated dynamic diamond anvil cell (RHdDAC) setup is presented. The setup enables the dynamic compression of samples at high temperatures by employing a piezoelectric actuator for pressure control and internal heaters for high temperature. The RHdDAC facilitates the precise control of compression rates and was tested in compression experiments at temperatures up to 1400 K and pressures of ∼130 GPa.

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Neuroblastoma is a malignancy developing from the embryonic neuroblasts of sympathetic nervous system. Primary sellar neuroblastomas are extremely rare (there are currently only 11 case reports in the literature). Possible development of neuroblastoma in sellar region expands differential diagnosis of local processes due to inclusion of neuroblastoma into the spectrum of suspected tumors.

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We present a microscopic picture rationalizing the surprisingly steep decrease in the bandgap with temperature in insulators, crystalline or otherwise. The gap narrowing largely results from fluctuations of long-wavelength optical phonons-when the latter are present-or their disordered analogs if the material is amorphous. We elaborate on this notion to show that possibly with the exception of weakly bound solids made of closed-shell electronic configurations, the existence of an insulating gap or pseudogap in a periodic solid implies that optical phonons must be present, too.

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Background: Until recently, tumors of the clivus and the anterior region of the posterior cranial fossa were considered extremely difficult to access and often inoperable using standard transcranial approaches. With the introduction into the neurosurgical practice of minimally invasive methods utilizing endoscopic techniques, it became possible to effectively remove hard-to-reach tumors, including central tumors of the anterior region of the posterior cranial fossa.

Methods: From 2008 to the present time, the inpatient institution has operated on 140 patients with various tumors of the base of the skull, localized to the clivus and anterior region of the posterior cranial fossa (65 men and 75 women).

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A Verwey-type charge-ordering transition in magnetite at 120 K leads to the formation of linear units of three iron ions with one shared electron, called trimerons. The recently-discovered iron pentoxide (FeO) comprising mixed-valent iron cations at octahedral chains, demonstrates another unusual charge-ordering transition at 150 K involving competing formation of iron trimerons and dimerons. Here, we experimentally show that applied pressure can tune the charge-ordering pattern in FeO and strongly affect the ordering temperature.

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In Extended Data Table 1 of this Letter, some of the elastic constants were reported incorrectly. This occurred as a result of an error in the script used to generate the numbers. The values of the elastic constants at room pressure cited in the manuscript on page 544 were derived using the same erroneous script, and the correct values and 1σ-uncertainties in the last given digit are C11 = 461.

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Nasal liquorrhea is a serious problem in surgery of skull base tumors, which is associated with a high risk of purulent-septic complications. This paper presents a case of successful repair of a cerebrospinal fluid fistula with an autologous platelet gel in the postoperative period after removal of meningioma of the anterior cranial fossa base, which was accompanied by a purulent-inflammatory complication in the surgical wound area.

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The convection or settling of matter in the deep Earth's interior is mostly constrained by density variations between the different reservoirs. Knowledge of the density contrast between solid and molten silicates is thus of prime importance to understand and model the dynamic behavior of the past and present Earth. SiO_{2} is the main constituent of Earth's mantle and is the reference model system for the behavior of silicate melts at high pressure.

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A portable double-sided pulsed laser heating system for diamond anvil cells has been developed that is able to stably produce laser pulses as short as a few microseconds with repetition frequencies up to 100 kHz. In situ temperature determination is possible by collecting and fitting the thermal radiation spectrum for a specific wavelength range (particularly, between 650 nm and 850 nm) to the Planck radiation function. Surface temperature information can also be time-resolved by using a gated detector that is synchronized with the laser pulse modulation and space-resolved with the implementation of a multi-point thermal radiation collection technique.

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We report in this paper an investigation on energy transfer processes from vibration to vibration and/or translation in thermal and subthermal regimes for the O + N system performed using quantum-classical calculations on different empirical, semiempirical, and ab initio potential energy surfaces. In particular, the paper focuses on the rationalization of the non-Arrhenius behavior (inversion of the temperature dependence) of the quasi-resonant vibration-to-vibration energy transfer transition rate coefficients at threshold. To better understand the microscopic nature of the involved processes, we pushed the calculations to the detail of the related cross sections and analyzed the impact of the medium and long-range components of the interaction on them.

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