Properties of coatings based on carbon and nitrogen-doped carbon obtained using a pulsed vacuum arc method

Diamond-like carbon coatings on hard-alloy substrates, including coatings doped with nitrogen about 1.0 μm thick have been obtained using a pulse vacuum-arc method. Three types of coatings have been investigated: a carbon diamond-like coating (C), a carbon coating doped with nitrogen (C : N), and a composite coating based on (C : N + C) layer

Invasive plant species and the Trans-siberian railway - back and forth

Railways are the ideal habitats for invasive alien species. Frequent disturbances create suitable open patches, destroy native plants, and propagules along the railroad can easily transport for many kilometers. This study is based on the inventory of current flora of Trans-Siberian railway track (Transsib) done in 2020-2021 (planned to continue also in next year

Large temperature dependence of the Casimir force at the metal-insulator transition

The dependence of the Casimir force on material properties is important for both future applications and to gain further insight on its fundamental aspects. Here we derive a general theory of the Casimir force for low-conducting compounds, or poor metals. For distances in the micrometer range, a large variety of such materials is described by universal equations containing a few parameters: the effective plasma frequency, dissipation rate of the free carriers, and electric permittivity in the infrared range. This theory can also describe inhomogeneous composite materials containing small regions with different conductivity. The Casimir force for mechanical systems involving samples made with compounds that have a metal-insulator transition shows an abrupt large temperature dependence of the Casimir force within the transition region, where metallic and dielectric phases coexist.Comment: 23 pages, 9 figure

Features of the Trans-siberian railway flora formation and alien plant migration within different regions

We consider the Trans-Siberian Railway, which connects two continents with a different set of native species, to be a unique object of research for analyzing the distribution of alien plants on a global scal

Spread of alien plants along the Trans-Siberian railway: the effect of biogeographical zones

We present results of the field inventory made in railway areas along the Trans-Siberian railwa

Doxorubicin pharmacokinetics in lymphoma patients treated with doxorubicin-loaded eythrocytes

Doxorubicin-loaded erythrocytes (DLE) were administrated to 15 lymphoma patients. Antibiotic peak concentration in blood decreased by 55%, doxorubicin circulated several times longer, and the area under the concentration-time curve increased 5 times if compared with standard doxorubicin administration. The DLE was well tolerated by patients

ROLE OF TLR2, TLR4 GENE POLYMORPHISM IN DEVELOPING MICROVASCULAR COMPLICATIONS IN ADOLESCENTS WITH TYPE 1 DIABETES MELLITUS

Long-term complications of type 1 diabetes mellitus (T1DM) in children and adolescents are an important problem in modern medicine. Recently, the role of immune mechanisms, in particular, chronic inflammation, in the development of both T1DM and its microvascular complications has been actively discussed. Activation of Toll-like receptor 2 (TLR2) and Toll-like receptor 4 (TLR4) leads to hyperproduction of proinflammatory cytokines, chemokines, adhesion molecules involved in the formation of diabetic microvascular complications. At the same time, TLR2 and TLR4 gene polymorphism alters the immune susceptibility to the endogenous ligands, which may increase the risk of diabetic microangiopathies. The aim of this study is to evaluate the frequency of genotypes and alleles of TLR2 and TLR4 genes distribution and to determine the content of TNFα, IL-1, VCAM-1, fractalkine, endothelin-1 in adolescents with T1DM with microvascular complications. We examined 139 adolescents with T1DM from 14 to 18 years old and 56 healthy teenagers. Patients with T1DM were divided into two groups: Group I – patients with poor glycemic control (HbA1C > 9.0%), (n = 64); Group II – patients with satisfactory glycemic control of T1DM (HbA1C ≤ 9.0%), (n = 75), including adolescents with optimal (HbA1C < 7.5%) and suboptimal glycemic control (7.5% ≤ HbA1C ≤ 9.0%) (ISPAD clinical practice consensus guidelines 2014). According to the presence of microvascular complications, the groups were subdivided into subgroups: Iа (n = 49), IIа (n = 38) – adolescents with verified microvascular disorders: diabetic retinopathy, nephropathy and neuropathy; Ib (n = 15), IIb (n = 37) – without microvascular complications. Allelic variants of TLR genes were determined using test systems GosNII genetics (Moscow). The content of cytokines in blood serum was carried out by the method of enzyme-linked immunosorbent assay “BIOSCIENCE”. Data were analyzed using software packages Statistica version 6.0. The assessment of TLR2 (Arg753Gln) and TLR4 (Thr399Ile) polymorphism distribution did not reveal significant differences between the observed subgroups and the control. In Ia and IIa subgroups (with complications) Asp299Gly variant was noted to be significantly less common when compared to subgroups Ib, IIb and controls. The presence of Gly allele in TLR4 gene was found to disrupt the expression of TNFα and VCAM-1 and can be considered protective for the development of microvascular complications

Phase changes of the Be/X-ray binary X Persei

We present high resolution optical spectroscopy and V band photometry obtained during the period 1987-2001 for the Be star X Persei/HD 24534, the counterpart to the X-ray pulsar 4U 0352+30. We find that throughout this interval X Per is highly active, with significant photometric and spectroscopic variability. We identify one episode of complete disc loss during this period (1988 May-1989 June), characterised by significant ΔV=0.6 mag optical fading and the presence of purely photospheric Hα and He I 6678 Å lines. Two further episodes of pronounced optical fading which did not result in the complete dispersal of the circumstellar disc were also identified (1994 October-1995 October and 1999 November-present). The emission line profiles of both Hα and He I 6678 Å also show significant variability. Cyclic changes in the strength of the peaks in both emission lines are observed, with periods ranging from 0.6-2 yrs - we attribute these to the presence of a one armed density wave in the inner circumstellar disc. Additional structure at large projected velocities is also present in the He I line - suggesting the presence of a significant density enhancement in the disc near the stellar surface (the "double disc'' of Tarasov & Roche). The evolution of the outer edge of the Hα emitting region of the circumstellar disc is followed during disc formation, and is found to increase rather slowly. This observation, combined with the presence of the one armed density wave and the rate of disc formation and loss all provide strong evidence for the hypothesis that the circumstellar disc of X Per is a viscous decretion disc, with angular momentum being supplied by an as yet unknown physical mechanism near the stellar surface

New phosphorus ylides in reactions of tertiary phosphines with phosphorylated quinone methide

A series of new phosphonium ylides have been synthesized by the reaction of dimethyl-(3,5-di-tert-butyl-4-oxo-2,5-cyclohexadienylidene)methylphosphonate with tertiary phosphines, the structure of dimethoxyphosphoryl-3,5-di-tert-butyl-4-hydroxyphenylmethylidene triphenylphosphorane has been confirmed by X-ray single crystal diffraction. © 2009

Antimicrobial peptides as promising drugs for treatment of primary viral pneumonia

The COVID-19 pandemic which began in March 2020 has again drawn attention to the problem of treating primary viral pneumonia (PVP), wherein damage to the tissues of the lower respiratory tract including functionally important alveolocytes occurs as a result of cell infection by pathogens of the Virae Kingdom. Whereas treatment of bacterial pneumonia is based on the basic approach related to the use of antibiotics (which effectiveness needs to be verified more often than ever due to the “curse of the resistance effect” — that, however, does not cancel the essence of the basic approach), efficient PVP treatment is feasible only in case of available etiotropic, but catastrophically few, drugs. Such drugs in case of the influenza A virus (Articulavirales: Orthomyxoviridae, Alphainfluenzavirus) have been known since the second part of the XXth century. However, no consensus was achieved among clinicians regarding particularly dangerous human coronaviruses (Nidovirales: Coronaviridae, Betacoronavirus) which threat has driven the world epidemiology in the XXIst century: SARS-CoV (subgenus Sarbecovirus), MERS-CoV (Merbecovirus), SARS-CoV-2 (Sarbecovirus). And we should be prepared to the fact that increase in population density and scaling up of anthropogenic impact on ecosystems elevates a probability of overcoming interspecies barriers by natural focal viruses and their penetration into the human population with adverse epidemic consequences. Therefore, PVP therapy should be developed systematically in the nearest future. Antimicrobial peptides (AMP) as the components of non-specific innate immunity against a wide range of infectious pathogens: bacteria (Bacteria), microscopic fungi (Fungi) and viruses (Virae) may serve as a platform for developing such system. Our review justifies a way to select such platform and provides well-known examples of successfully used AMP in treatment of PVP and related pathological conditions