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Nanodispersed Oxides-Plasma-Chemical Synthesis and Properties

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Plasma Science and Technology 2007年第5期9卷 603-610页

作者： Gheorghi VISSOKOV katerina ZAHARIEVA Institute of Catalysis Bulgarian Academy of SciencesSofia 1113Bulgaria Chemistry Chair St.Ivan Rilski University of Mining and GeologySofia 1700Bulgaria

We discuss the plasma-chemical synthesis and the properties of transition metals oxides, Al2O3, SiO2, rare-earth oxides, oxides for ceramics and metal-ceramics, and oxides used as catalysts. Bearing in mind the indisputable advantages of using plasma-chemically synthesized nanodispersed oxides for the needs of various industrial fields, we set out to review the articles published in the past few years devoted to the problems of plasma-chemical synthesis and characterization of nanodispersed oxides.

关键词： plasma synthesis nanodispersed oxides properties

Model of fractured medium and nondestructive control of composite materials

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Chinese Journal of Aeronautics 2024年第2期37卷 93-99页

作者： Vasily GOLUBEV Ilia NIKITIN katerina BEKLEMYSHEVA Department of Computers Science and Numerical Mathematics Moscow Institute of Physics and TechnologyDolgoprudny 141700Russia Mathematical Modeling and Management Department of InformatizationInstitute of Computer Aided Design RASMoscow 123056Russia

Non-destructive testing of composites is an important issue in the modern aircraft *** are susceptible to the barely visible impact damage which can affect the residual strength of the material and occurs both during production and *** continuum model for describing the damaged zone is *** slip theory relations used for a continuous distribution of slip planes are *** the initial stage,the isotropic background model is *** model allows the material slippage along the fractures based on the Coulomb friction law with the small viscous *** this regime,the govern system of equations becomes *** overcome this difficulty,the explicit-implicit grid-characteristic scheme is *** standard ultrasound diagnostic procedure of damaged composite materials is successfully *** with the trivial free-surface fracture model,different reactions on the compression and stretch waves are *** approach provided an effective way for the simulation of complex dynamic behavior of damage zones.

关键词： Non-destructive testing Composite materials Numerical modeling Continuum model Grid-characteristic method

Metabolites and micronutrition in modulating amyotrophic lateral sclerosis

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Neural Regeneration Research 2024年第6期19卷 1183-1184页

作者： katerina Claud Jun Sun Department of Medicine University of Illinois ChicagoChicagoILUSA Jesse Brown VA Medical Center Chicago ChicagoILUSA

Amyotrophic lateral sclerosis(ALS)is a progressive neurodegenerative *** majority of ALS cases are sporadic with only about 20%of familial *** in families with genetic predisposition,there is significant phenotypic va... 详细信息

关键词： sclerosis amyotrophic cases

Endoprosthesis implantation at the pharyngo-esophageal level:Problems,limitations and challenges

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World Journal of Gastroenterology 2006年第13期12卷 2103-2108页

作者： Efthimios Eleftheriadis katerina Kotzampassi Department of Surgery University of Thessaloniki Medical School ThessalonikiGreece

AIM： To present our experience with endoscopic placement of an esophageal endoprosthesis in 19 patients. METHODS： A retrospective evaluation was made for the use of 19 stents positioned at the level of the cervical esophagus： 11 for malignant tumours （7 causing obstruction, 4 complicated by an esophago -tracheal or -cutaneous fistula）, and 8 for an acquired benign tracheo-esophageal fistula due to prolonged intubation. The covered Ultraflex stent was used in all cases except two. These two patients had an esophagocutaneous fistula following laryngectomy and a Flamingo Wall stent was used. RESULTS： Stent implantation was technically successful in all patients. Dysphagia score was improved from 3 to 2 in stenosis patients, while sealing of the fistula was achieved in all cases. The median hospital stay was 3 d for malignant turnout patients and 13.5 d for esophagocutaneous fistula patients. One Ultraflex stent and two Flamingo Wall stents were easily removed 33 d and 3 months respectively after implantation when the fistulas had totally occluded. CONCLUSION： Endoprosthesis implantation for malignancy and/or fistula of malignant or benign origin at the level of the cervical esophagus is an easy, well tolerated, safe and effective procedure with no complications or mortality.

关键词： Cervical endoprosthesis Pharyngo-esophageal stenosis Dysphagia Esophageal carcinoma Esophagotracheal fistula

P-Tree Structures and Event Horizon： Efficient Event-Set Implementations

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Journal of Computer Science & Technology 2006年第1期21卷 19-26页

作者： katerina Asdre Stavros D. Nikolopoulos Department of Computer Science University of Ioannina GR-45110 Ioannina Greece

This paper describes efficient data structures, namely the Indexed P-tree, Block P-tree, and Indexed-Block P-tree （or/P-tree, BP-tree, and IBP-tree, respectively, for short）, for maintaining future events in a general purpose discrete event simulation system, and studies the performance of their event set algorithms under the event horizon principle. For comparison reasons, some well-known event set algorithms have been selected and studied, that is, the Dynamic-heap and the P-tree algorithms. To gain insight into the performance of the proposed event set algorithms and allow comparisons with the other selected algorithms, they are tested under a wide variety of conditions in an experimental way. The time needed for the execution of the Hold operation is taken as the measure for estimating the average time complexity of the algorithms. The experimental results show that the BP-tree algorithm and the IBP-tree algorithm behave very well with the event set of all the sizes and their performance is almost independent of the stochastic distributions.

关键词： discrete-event simulation event set algorithms hold model event horizon data structures heap P-tree P-tree structures

Seismic fragility curves for structures using non-parametric representations

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Frontiers of Structural and Civil Engineering 2017年第2期11卷 169-186页

作者： Chu MAI katerina KONAKLI Bruno SUDRET Risk Safety & Uncertainty Quantification Institute of Structural Engineering ETH Ziirich Ziirich CH-8093 Switzerland

Fragility curves are commonly used in civil engineering to assess the vulnerability of structures to earthquakes. The probability of failure associated with a prescribed criterion （e.g., the maximal inter-storey drift of a building exceeding a certain threshold） is represented as a function of the intensity of the earthquake ground motion （e.g., peak ground acceleration or spectral acceleration）. The classical approach relies on assuming a lognormal shape of the fragility curves; it is thus parametric. In this paper, we introduce two non-parametric approaches to establish the fragility curves without employing the above assumption, namely binned Monte Carlo simulation and kernel density estimation. As an illustration, we compute the fragility curves for a three-storey steel frame using a large number of synthetic ground motions. The curves obtained with the non-parametric approaches are compared with respective curves based on the lognormal assumption. A similar comparison is presented for a case when a limited number of recorded ground motions is available. It is found that the accuracy of the lognormal curves depends on the ground motion intensity measure, the failure criterion and most importantly, on the employed method for estimating the parameters of the lognormal shape.

关键词： earthquake engineering fragility curves lognormal assumption non-parametric approach kernel density estimation epistemic uncertainty

A new GIS-compatible methodology for visibility analysis in digital surface models of earth sites

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Geoscience Frontiers 2021年第4期12卷 21-33页

作者： katerina Ruzickova Jan Ruzicka Jan Bitta VSB–Technical University of Ostrava Czech Republic

As a GIS tool,visibility analysis is used in many areas to evaluate both visible and non-visible *** analysis builds on a digital surface model describing the terrain morphology,including the position and shapes of all objects that can sometimes act as visibility ***,some barriers,for example vegetation,may be permeable to a certain *** extensive research and use of visibility analysis in different areas,standard GIS tools do not take permeability into *** article presents a new method to calculate visibility through partly permeable *** method is based on a quasi-Monte Carlo simulation with 100 iterations of visibility *** iteration result represents 1%of vegetation permeability,which can thus range from 1%to 100%visibility behind vegetation *** main advantage of the method is greater accuracy of visibility results and easy implementation on any GIS *** incorporation of the proposed method in GIS software would facilitate work in many fields,such as architecture,archaeology,radio communication,and the military.

关键词： Digital surface model Visibility analysis Topographic data processing Obstacle object Permeability

Role of interleukin-6 in Barrett's esophagus pathogenesis

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World Journal of Gastroenterology 2013年第15期19卷 2307-2312页

作者： katerina Dvorak Bohuslav Dvorak Department of Cellular and Moleculart Medicine The University of ArizonaTucsonAZ 85724United States Department of Pediatrics and Steele Children's Research Center The University of ArizonaTucsonAZ 85724United States

Barrett's esophagus (BE) is a metaplastic lesion of the distal esophagus arising as a consequence of chronic gastroesophageal reflux disease. Multiple studies show that BE is associated with increased risk of esophageal adenocarcinoma (EAC). Epidemiological studies and animal models demonstrate that chronic inflammation triggered by repeated exposure to refluxate predisposes to the development of BE and EAC. The chronic inflammation is associated with cytokine alterations. Interleukin 6 (IL-6) is a cytokine that stimulates cell proliferation and apoptosis resistance is frequently increased in different cancers. Importantly, IL-6 and transcriptional factor signal transducer and activator of transcription 3 (STAT3) that is activated by IL-6 are also increased in BE and EAC. This review critically appraises the role of IL-6/STAT3 pathway in progression of BE to EAC from the published evidence currently available.

关键词： Barrett’s esophagus Interleukin 6 Bile acids Inflammation Apoptosis

Determining effects of impact loading on residual strength of fiber-metal laminates with grid-characteristic numerical method

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Chinese Journal of Aeronautics 2021年第7期34卷 1-12页

作者： katerina BEKLEMYSHEVA Vasily GOLUBEV Igor PETROV Alexey VASYUKOV Moscow Institute of Physics and Technology DolgoprudniyRussia

The Grid-Characteristic numerical Method(GCM)that is quite common in solving aero and hydrodynamic problems can also be applied for mechanics of *** allows to implement complex border and contact conditions,including the non-reflecting border and the destructible *** this conditions are very important for the precise and effective modeling of LowVelocity Impacts(LVI)on fiber and Fiber-Metal Laminates(FML)and the resulting Barely Visible Impact Damage(BVID)that influences the residual strength of a composite aircraft *** is the type of damage that is not visible by the naked eye and can be hardly detected by a standard ultrasound equipment that is used for regular *** can appear during any weak impacts like bird strike or *** its influence on the residual strength of the part is very important to define the priorities of development of ultrasound *** this paper,the GCM was applied for a full cycle of loading of an FML aircraft cover *** FML consisted of a Carbon Fiber Reinforced Polymer(CFRP)and a single titanium layer on the upper *** cycle of loading in a single calculation consisted of an LVI caused by a small striker and a comparatively slow compressive in-plane ***-dimensional patterns of velocity and stress distributions over the time of calculation are *** patterns,obtained via the Hashin failure criterion are given and analyzed.

关键词： Fiber-metal laminate Grid-characteristic method Low-velocity impact Numerical modeling Residual strength