The operating experience of axial single-wheels indicates the need to protect the blades from erosion damage. This can be achieved by applying a protective coating. We have proposed a method for ...processing bladed disk by biaxial rotation in a vacuum volume. The selection of the trajectory is supposed to be carried out using numerical simulation methods. An important parameter in this case is the smoothed variable to eliminate noise from the coating thickness. The article presents the selection of this parameter based on an experiment with samples of various forms with a protective coating of the (Ti-V)N system.
Abstract
PVD coating deposition is a considerable way to prevent the gas turbine engine blade from erosive wear. However, the process for blisks is complicated by the part complex shape which leads ...to uneven film thickness. The research considers an approach for optimizing the blisk trajectory in a vacuum chamber. This approach reduced the calculated non-uniformity of the coating thickness from 4.3-10.8 to 6.2-10.4 μm.
In this work, we developed and validated a robust and sensitive method of liquid chromatography with high-resolution mass spectrometry in parallel reaction monitoring (PRM) mode for ST-246 ...(tecovirimat) quantification in human blood plasma. The method was compared with the multiple reaction monitoring (MRM) technique and showed better selectivity and similar sensitivity in a wider concentration range (10–5000 ng/mL). Within this range, intra- and interday variability of precision and accuracy were within acceptable ranges in accordance with the European Medicines Agency guidelines, and recovery was 87.9–100.6%. Samples were stable at 4 °C within 48 h and at −20 °C up to 3 months. The recovery and matrix effects in the proposed HRMS method were about 5% higher than those reported for the MRM method, but the PRM method showed better accuracy with comparable precision. It was found that the ST-246 concentration shown by the PRM method is approximately 24% higher than the output of the MRM one. Nonetheless, the high selectivity with similar sensitivity, as compared with traditional MRM methods, makes the proposed approach attractive for research and clinical use.
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The aim of this work was to develop and validate a sensitive and robust method of liquid chromatography coupled with tandem mass spectrometry to quantitate ST-246 (tecovirimat) in plasma using an ...internal standard (2-hydroxy-N-{3,5-dioxo-4-azatetracyclo 5.3.2.02.6.08.10dodec-11-en-4-yl}-5-methylbenzamide). The method was validated in negative multiple reaction monitoring mode following recommendations of the European Medicines Agency for the validation of bioanalytical methods. The calibration curve for the analyte was linear in the 10−2500 ng/mL range with determination coefficient R2 > 0.99. Intra- and inter-day accuracy and precision for three concentrations of quality control were <15%. Testing of long-term stability of ST-246 (tecovirimat) in plasma showed no degradation at −20 °C for at least 3 months. The method was applied to a clinical assay of a new antipoxvirus compound, NIOCH-14. Thus, the proposed method is suitable for therapeutic drug monitoring of ST-246 (tecovirimat) itself and of NIOCH-14 as its metabolic precursor.
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To resolve the problem of the connectedness of the territory of the Russian Federation we need the implementation of scientific and technological solutions, for the development and implementation of ...which we form complex scientific and technical programs and complex projects of the full innovation cycle. To effectively solve the problems of spatial development of the regions of the Russian Federation, it is necessary to introduce new technologies to ensure energy, transport, information and socio-cultural connectivity of sparsely populated and hard-to-reach territories. Information connectivity of the territory can be ensured through the creation and use of information and analytical systems for remote monitoring of objects and resources on the territory of the state.
When applying a vacuum-arc discharge plasma coating to profilecomposite items, such as twin turbine blades, unicycle blades, etc., a problem might occur with ensuring the tolerance on the coating ...thickness. This article presents the obtained dependence of the nonuniformity of the coating thickness on the geometric parameters of the inter-blade channel—its length and width. We develop a simulation model for calculating the distribution of the thickness of the vacuum-arc discharge plasma coating for the profilecomposite parts having shadow zones.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The plankton community was collected during the winter season from the Isfjord aquatic area, on the western coast of Spitsbergen Island, on November 30–December 6, 2015. Sampling was carried out with ...a plankton net and bathometric catches on board of the research vessel
Dalnie Zelentsy
. The assemblages of micro- and mesoplankton from several aquatic areas of the central part of Isfjord have been studied qualitatively and quantitatively. These areas contain waters with different hydrological structures. We noted that the number of nauplii of small copepods in samples varied significantly depending on sampling method. The main emphasis of this research is the methodology of plankton study in the Arctic waters during winter seasons.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Periodontitis is a chronic inflammatory disease characterized by the destruction of the supporting structures of the teeth. Its high prevalence and negative effects on quality of life make it one of ...the current problems in dentistry. Porphyromonas gingivalis (P. gingivalis) is the predominant periodontal pathogen that expresses a number of virulence factors involved in the pathogenesis of periodontitis. P. gingivalis fimbriae are a critical factor in the interaction between the organism and the host tissue. They promote both bacterial adhesion and invasion into the target sites. Fimbriae are capable of binding to human saliva components, extracellular matrix proteins, and commensal bacteria, as well as firmly binding to the cellular integrin α5β1. After attachment to α5β1-integrin, P. gingivalis is captured by cellular pseudopodia, which makes invagination through an actin-mediated pathway possible. It has been proven that the invagination event also requires the participation of the host cell dynamin, actin fibers, microtubules and lipid rafts. Work has emerged investigating mutations in the proline-rich terminal domain (PRD) and their impact on disease development. Salivary antimicrobial peptides are early protective factors against microbial attack. Of great interest is fibronectin (FN) as the main competitor of P. gingivalis fimbriae. The FN can interact with cells in three different regions: the central cell-binding domain (CCBD), the COOH terminal heparin-binding domain (Hep2), and the type III connecting segment (IIICS), including the CS1 region (Yamada, 1991). CCBD is the major cell-adhesion domain of FN and contains an Arg–Gly–Asp (RGD) motif that is recognized by members of the cell adhesion receptor integrin family, including a5b1, which is the primary FN receptor in many cell types. The work focuses on identifying the relationship between the development of periodontitis and the presence of mutations in the adhesion domains of salivary proteins such as cellular fibronectin (cFN) and dynamin-2 (DYNM2).
The end-Cretaceous Chicxulub impact triggered Earth's last mass-extinction, extinguishing ~ 75% of species diversity and facilitating a global ecological shift to mammal-dominated biomes. Temporal ...details of the impact event on a fine scale (hour-to-day), important to understanding the early trajectory of mass-extinction, have largely eluded previous studies. This study employs histological and histo-isotopic analyses of fossil fish that were coeval with a unique impact-triggered mass-death assemblage from the Cretaceous-Paleogene (KPg) boundary in North Dakota (USA). Patterns of growth history, including periodicity of ẟ
O and ẟ
C and growth band morphology, plus corroborating data from fish ontogeny and seasonal insect behavior, reveal that the impact occurred during boreal Spring/Summer, shortly after the spawning season for fish and most continental taxa. The severity and taxonomic symmetry of response to global natural hazards are influenced by the season during which they occur, suggesting that post-impact perturbations could have exerted a selective force that was exacerbated by seasonal timing. Data from this study can also provide vital hindsight into patterns of extant biotic response to global-scale hazards that are relevant to both current and future biomes.
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