Publications by authors named "Tatyana Ivanova"

Sol-gel spin coating method was employed for depositing TiO and Ag-doped TiO films. The effects of Ag doping and the annealing temperatures (300-600 °C) were studied with respect to their structural, morphological, vibrational, and optical properties. Field Emission Scanning Electron microscopy (FESEM) investigation exhibited the grained, compact structures of TiO-based films.

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Article Synopsis
  • The study explores the growing role of multifunctional surfaces in mechanical engineering, focusing on products with complex coatings and composite materials.
  • It introduces an innovative asymmetric morphological filter that enhances texture analysis by adjusting nesting indices for morphological operations, improving computational efficiency.
  • The research provides an algorithm for selecting filter types and parameters, achieving less than 3% relative error in surface analysis, beneficial for evaluating tribological properties of advanced materials.
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Guided 2D exciton-polaritons, resulting from the strong coupling of excitons in semiconductors with nonradiating waveguide modes, provide an attractive approach toward developing novel on-chip optical devices. These quasiparticles are characterized by long propagation distances and efficient nonlinear interactions but cannot be directly accessed from the free space. Here we demonstrate a powerful approach for probing and manipulating guided polaritons in a TaO slab integrated with a WS monolayer using evanescent coupling through a high-index solid immersion lens.

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This work presents a facile sol-gel method for the deposition of ZnO and ZnO:Mg films. The films are spin coated on silicon and quartz substrates. The impact of magnesium concentrations (0, 0.

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In our study, transparent and conductive films of NiO were successfully deposited by sol-gel technology. NiO films were obtained by spin coating on glass and Si substrates. The vibrational, optical, and electrical properties were studied as a function of the annealing temperatures from 200 to 500 °C.

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The rise of quantum science and technologies motivates photonics research to seek new platforms with strong light-matter interactions to facilitate quantum behaviors at moderate light intensities. Topological polaritons (TPs) offer an ideal platform in this context, with unique properties stemming from resilient topological states of light strongly coupled with matter. Here we explore polaritonic metasurfaces based on 2D transition metal dichalcogenides (TMDs) as a promising platform for topological polaritonics.

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Two types of Fe(III) polynuclear iron(III) 1D-chain coordination compounds of the general formula [Fe (L)(tvp)]BPh nSolv, where L = dianion of N,N'-ethylenebis (benzoylacetylacetone)2,2'-imine (bzacen), tvp = 1,2-di(4-pyridyl)ethylene were synthesized and studied by the electron paramagnetic resonance (EPR) and magnetic susceptibility methods in the temperature range (100-300) К. Two types of spin-variable complexes are formed depending on the time of precipitation of the complexes from the same solution leading to differently solvated species. They have different characteristics of the local ligand field and the spin transition behavior.

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The adaptation of human immunodeficiency virus type-1 (HIV-1) to an array of physiologic niches is advantaged by the plasticity of the viral genome, encoded proteins, and promoter. CXCR4-utilizing (X4) viruses preferentially, but not universally, infect CD4+ T cells, generating high levels of virus within activated HIV-1-infected T cells that can be detected in regional lymph nodes and peripheral blood. By comparison, the CCR5-utilizing (R5) viruses have a greater preference for cells of the monocyte-macrophage lineage; however, while R5 viruses also display a propensity to enter and replicate in T cells, they infect a smaller percentage of CD4+ T cells in comparison to X4 viruses.

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Genetic and epigenetic alterations in cervical carcinomas were investigated using NotI-microarrays containing 180 cloned sequences flanking all NotI-sites associated with genes on chromosome 3. In total, 48 paired normal/tumor DNA samples, specifically enriched in NotI-sites, were hybridized to NotI-microarrays. Thirty genes, including tumor suppressors or candidates (for example, VHL, RBSP3/CTDSPL, ITGA9, LRRC3B, ALDH1L1, EPHB1) and genes previously unknown as cancer-associated (ABHD5, C3orf77, PRL32, LOC285375, FGD5 and others), showed methylation/deletion in 21-44% of tumors.

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p53, an important tumor suppressor protein, exerts its function mostly as a sequence-specific transcription factor and is subjected to multiple posttranslational modifications in response to genotoxic stress. Recently, we discovered that lysine methylation of p53 at K372 by Set7/9 (also known as SET7 and Set9) is important for transcriptional activation and stabilization of p53. In this report we provide a molecular mechanism for the effect of p53 methylation on transcription.

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Tissue inhibitor of metalloproteinase-2 (TIMP-2) is an endogenous inhibitor of matrix metalloproteinases (MMPs). This multifunctional protein regulates activities of MMPs and possesses growth promoting effect in cell culture, anti-tumoral, anti-apoptotic and anti-angiogenic effects in animal model systems in vivo. It has been shown that this gene is downregulated in cervical carcinomas.

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Background: Expression of the retinoic acid receptor beta2 (RAR-beta2), a putative tumor suppressor gene, is reduced in various human cancers, including squamous cell carcinomas (SCC) of the uterine cervix. The mechanism of the inhibition of RAR-beta2 expression remains obscure. We examined whether methylation of RAR-beta2 gene could be responsible for this silencing in cervical SCC.

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