Publications by authors named "Semenova T"

The requirement for the development of advanced technologies is the need to create new functional thermostable soluble polysilsesquioxanes. Combining the potential of organosilicon chemistry and the chemistry of heterocyclic compounds is a promising direction for the formation of novel organosilicon polymer systems with new properties and new possibilities for their practical application. Using the classical method of hydrolysis and polycondensation of previously unknown trifunctional (trimethoxysilylpropyl)glutarimide in the presence or absence of an acid or base catalyst, a universal approach to the formation of new thermostable soluble polysilsesquioxanes with glutarimide side-chain groups is proposed, which forms the basis for the synthesis of polysilsesquioxane polymers with different functionality.

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A novel water-soluble polymer nanocomposite containing ultra-small iron oxide nanoparticles, intercalated into a biocompatible matrix of 1-vinyl-1,2,4-triazole and -vinylpyrrolidone copolymer has been synthesized for the first time. The use of an original polymer matrix ensured effective stabilization of the crystalline phase of iron oxides at an early stage of its formation in an ultra-small (2-8 nm, average diameter is 4.8 nm) nanosized state due to its effective interaction with the functional groups of copolymer macromolecules.

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New water-soluble nanocomposites with cobalt oxide nanoparticles (CoONPs) in a poly(1-vinyl-1,2,4-triazole) (PVT) matrix have been synthesized. The PVT used as a stabilizing polymer matrix was obtained by radical polymerization of 1-vinyl-1,2,4-triazole (VT). The polymer nanocomposites with CoO nanoparticles were characterized by ultraviolet-visible, Fourier-transform infrared spectroscopy, atomic absorption spectroscopy, transmission electron microscopy, dynamic light scattering, gel permeation chromatography, and simultaneous thermogravimetric analysis.

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Activity of extracellular enzymes was assessed in 20 strains of microscopic fungi involved in biodegradation of technical objects exploited under tropical climate conditions (Vietnam). It was found that 19 strains possessed catalase activity, 18 strains had phenol oxidase activity, and eight strains had protease activity. The effect of industrial biocides on the activity of these enzymes was also assessed.

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Narrow dispersed poly(1-vinyl-1,2,4-triazole) (PVT) was synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization of 1-vinyl-1,2,4-triazole (VT). AIBN as the initiator and dithiocarbamates, xanthates, and trithiocarbonates as the chain transfer agents (CTA) were used. Dithiocarbamates proved to be the most efficient in VT polymerization.

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A new hydrophilic polymeric nanocomposite containing AgNPs was synthesized by chemical reduction of metal ions in an aqueous medium in the presence of the copolymer. A new water-soluble copolymer of 1-vinyl-1,2,4-triazole and vinylsulfonic acid sodium salt (poly(VT-co-Na-VSA)) was obtained by free-radical copolymerization and was used as a stabilizing precursor agent. The structural, dimensional, and morphological properties of the nanocomposite were studied by UV-Vis, FTIR, X-ray diffraction, atomic absorption, transmission and scanning electron microscopy, dynamic and electrophoretic light scattering, gel permeation chromatography, thermogravimetric analysis, and differential scanning calorimetry.

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New stable nanocomposites with copper nanoparticles (CuNPs) in a polymer matrix have been synthesized by green chemistry. Non-toxic poly-N-vinylimidazole was used as a stabilizing polymer matrix and ascorbic acid was used as a reducing agent. The polymer CuNPs nanocomposites were characterized by Fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV) spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic absorption spectroscopy (AAS), and thermogravimetric analysis (TGA).

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Unlabelled: was to assess the prognostic value of the plasma neuron-specific enolase (NSE) level as a predictor of functional outcome and motor function recovery in the acute period of ischemic stroke (IS).

Materials And Methods: Fifty patients with IS have been examined. On admission to the hospital and at 12-14 days after stroke onset, a clinical and neurological examination have been carried out with the supplementary quantitative assessment of neurological deficit severity according to the National Institutes of Health Stroke Scale (NIHSS), functional outcome according to the Modified Rankin Scale, and Rivermead Mobility Index.

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Cerebral amyloid angiopathy (CAA) is caused by the deposition of β-amyloid in small vessels in the cerebral cortex and leptomeninges. Nowadays, CAA is recognized more often due to the development of neuroimaging technologies. The frequency of CAA increases in old age that explains its frequent association with cardiovascular diseases.

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T cells recognize peptides bound to major histocompatibility complex (MHC) class I and class II molecules at the cell surface. This recognition is accomplished by the expression of T cell receptors (TCR) which are required to be diverse and adaptable in order to accommodate the various and vast number of antigens presented on the MHCs. Thus, determining TCR repertoires of effector T cells is necessary to understand the immunological process in responding to cancer progression, infection, and autoimmune development.

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Meeting global demand for growing the science, technology, engineering, and mathematics (STEM) workforce requires solutions for the shortage of qualified instructors. We propose and evaluate a model for scaling up affordable access to effective STEM education through national online education platforms. These platforms allow resource-constrained higher education institutions to adopt online courses produced by the country's top universities and departments.

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A high second harmonic generation response is demonstrated by a PbO(NO) lead oxynitrate whose identity was verified upon reinvestigation of the PbO-Pb(NO) system. Its crystal structure exhibits a unique cationic [PbO] framework hosting orientationally ordered NO triangles in the channels. Easy preparation and high thermal stability (until ∼500 °C in air) suggest it to be a new promising NLO material.

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This review deals with characteristics of peptidases of fungi whose life cycles are associated with insects to varying degrees. The review examines the characteristic features of the extracellular peptidases of entomopathogenic fungi, the dependence of the specificity of these peptidases on the ecological characteristics of the fungi, and the role of peptidases in the development of the pathogenesis. Data on the properties and physiological role of hydrolytic enzymes of symbiotic fungi in "fungal gardens" are also considered in detail.

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Treatment options for Hepatitis C infection have greatly improved with direct-acting antiviral (DAA) combinations achieving high cure rates. Nevertheless, the cost of this treatment is still high and access to treatment in many countries has been preferentially reserved for patients with more severe fibrosis (F3 and F4). In this French nationwide study, we investigated the epidemiological characteristics and genotype distribution of hepatitis C virus (HCV) in treatment-naive patients with METAVIR fibrosis stages between F0 and F2 in order to identify patient profiles that became eligible for unrestricted treatment in a second period.

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Since the discovery of mouse hybridoma technology by Kohler and Milstein in 1975, significant progress has been made in monoclonal antibody production. Advances in B cell immortalization and phage display technologies have generated a myriad of valuable monoclonal antibodies for diagnosis and treatment. Technological breakthroughs in various fields of 'omics have shed crucial insights into cellular heterogeneity of a biological system in which the functional individuality of a single cell must be considered.

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Unlabelled: In recent years, all medical specialists, including ophthalmologists, have been facing the problem of mixed infections. Recurrent inflammation in the anterior and posterior eye segments is often a result of infection by more than one variety of pathogens.

Material And Methods: Over the period 2013-2016, 34 patients (14 men and 20 women) with different inflammatory processes in the eye who appeared DNA-positive for mycoplasmas (Mycoplasma hominis, Ureaplasma urealyticum) and/or chlamydiae (Chlamydia trachomatis) (PCR testing of tear fluid and/or urine) were followed up.

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Background: According to rare studies, the age at EBV primary infection (PI) has recently risen in some developed countries. A later age at infection is generally considered a risk factor for severe EBV PI, although few studies exist on this subject. Our investigation aimed to determine whether EBV seroprevalence and EBV PI epidemiology have evolved in France, and to what extent age and infection intensity (regarding biological parameters) are correlated.

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Unlabelled: Approximately a quarter of the world's population at some point in life is at risk of developing shingles (Herpes Zoster). In 10-20% of cases the first branch of the trigeminal nerve gets involved (Herpes Zoster Ophthalmicus, HZO). Ophthalmic complications of HZO are able to cause a significant reduction in visual function.

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We characterized fungal communities in dry and moist tundra and investigated the effect of long-term experimental summer warming on three aspects of functional groups of arctic fungi: richness, community composition and species abundance. Warming had profound effects on community composition, abundance, and, to a lesser extent, on richness of fungal functional groups. In addition, our data show that even within functional groups, the direction and extent of response to warming tend to be species-specific and we recommend that studies on fungal communities and their roles in nutrient cycling take into account species-level responses.

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Background: Epstein-Barr virus (EBV) displays oncogenic properties, particularly in the immunocompromised host. Notably, hematopoietic stem cell transplantation (HSCT) recipients with a detectable blood EBV viral load (BEBVL) are considered at higher risk of post-transplant lymphoproliferative diseases (PTLD). Therefore, BEBVL is monitored after HSCT, and preemptive rituximab may be used in patients with high values.

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Within the framework of the Federal External Quality Assessment (EQA) System and in the context of postgraduate training improvement for health workers in 2010-2014, specialists from the laboratories of the therapeutic-prophylactic organizations and institutions of the Russian Federal Service for Supervision of Consumer Rights Protection and Human Welfare were examined for their professional competence in microscopically identifying the pathogens of parasitic diseases in feces. The virtual remote educational computer technology tools that included different combinations of 16 helminthic species, 5 intestinal protozoan species, and a number of artefacts, were used. The specialists from 984 laboratories of multidisciplinary therapeutic-prophylactic organizations and hygiene and epidemiology centers in all Federal Districts of the Russian Federation were covered.

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The first WHO international standard for Epstein-Barr virus (EBV) (WHO EBV standard) for nucleic acid amplification technology (NAT)-based assays was commercialized in January 2012 by the National Institute for Biological Standards and Control. In the study reported here, we compared whole-blood EBV DNA load (EDL) results from 12 French laboratories for seven samples (Quality Controls for Molecular Diagnostics 2013 proficiency panel) in order to determine whether expression in international units reduces interlaboratory variability in whole-blood EDLs. Each testing laboratory used a conversion factor to convert EDL results from copies per milliliter to international units per milliliter.

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Many arctic ecological processes are regulated by soil temperature that is tightly interconnected with snow cover distribution and persistence. Recently, various climate-induced changes have been observed in arctic tundra ecosystems, e.g.

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During Epstein-Barr virus (EBV) latency, the EBV genome is largely silenced by methylation. This silencing is overturned during the switch to the lytic cycle. A key event is the production of the viral protein Zta which binds to three Zta-response elements (ZRE) from the Rta promoter (Rp), two of which (ZRE2 and ZRE3) include three CpG motifs methylated in the latent genome.

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Fungi, including symbionts, pathogens and decomposers, play crucial roles in community dynamics and nutrient cycling in terrestrial ecosystems. Despite their ecological importance, the response of most arctic fungi to climate warming is unknown, so are their potential roles in driving the observed and predicted changes in tundra communities. We carried out deep DNA sequencing of soil samples to study the long-term effects of experimental warming on fungal communities in dry heath and moist tussock tundra in Arctic Alaska.

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