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Which digital games are appropriate for our children?
PublicationChapter contains advice on which digital games are accessible for children with diverse impairments. It providess a process for choosing the device, the game and adjusting it. It might be of use for therapists, techers and caregivers.
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Resonant DC link inverters for AC motor drive systems – critical evaluation
PublicationIn this survey paper, resonant and quasiresonant DC link inverters are reexamined for AC motor drive applications. Critical evaluation of representative topologies is based on simulation and waveform analysis to characterize current/voltage stress of components, control timing constraints and feasibility. A special concern over inverter common-mode voltage and voltage gradient du/dt limitation capacity is discussed for motor bearing...
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Metal dusting phenomena of 501 AISI furnace tubes in refinery fractional distillation unit
PublicationThe purpose of this investigation was to conduct the failure analysis of 501 AISI furnace tubes places before distillation column in fractional distillation unit. The investigated furnace tubes were planned to work for ten years however after just two years of exploitation <30% of the material left. The observed corrosion process had the intense and complex character. The well-adhered shiny black deposits and deep, round pits were...
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Microplastics in water resources: Global pollution circle, possible technological solutions, legislations, and future horizon
PublicationBeneath the surface of our ecosystems, microplastics (MPs) silently loom as a significant threat. These minuscule pollutants, invisible to the naked eye, wreak havoc on living organisms and disrupt the delicate balance of our environment. As we delve into a trove of data and reports, a troubling narrative unfolds: MPs pose a grave risk to both health and food chains with their diverse compositions and chemical characteristics....
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Nonlinear fuzzy control of the dissolved oxygen in activated sludge processes
PublicationWastewater treatment plant is generally a complex, multivariable, time varying and nonlinear large scale industrial system. Moreover, interactions between the components are very strong. The dissolved oxygen tracking problem is one of the most complex and fundamental issues of biological processes. Air for the aerated tanks is supplied by aeration system (blowers, pipes, diffusers). It is a complex dynamic system. The new control...
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Nanoparticle-free tissue-mimicking phantoms with intrinsic scattering
PublicationWe present an alternative to the conventional approach, phantoms without scattering nanoparticles, where scattering is achieved by the material itself: spherical cavities trapped in a silicone matrix. We describe the properties and fabrication of novel optical phantoms based on a silicone elastomer polydimethylsiloxane (PDMS) and glycerol mixture. Optical properties (absorption coefficient µa, reduced scattering coefficient µs',...
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Features of Nonlinear Sound Propagation in Vibrationally Excited Gases
PublicationWeakly nonlinear sound propagation in a gas where molecular vibrational relaxation takes place is studied. New equations which govern the sound in media where the irreversible relaxation may take place are derived and discussed. Their form depends on the regime of excitation of oscillatory degrees of freedom, equilibrium (reversible) or non-equilibrium (irreversible), and on the comparative frequency of the sound in relation to...
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High-quality Experiment Dedicated to microGravity Exploration, Heat Flow and Oscillation Measurement from Gdańsk
PublicationIn this paper we propose HEDGEHOG (High-quality Experiment Dedicated to microGravity Exploration, Heat flow and Oscillation measurement from Gdańsk) REXUS experiment to investigate vibrational and heat flow phenomena during the whole (ascent, microgravity phase, descent and recovery) flight of a sounding rocket. First, a proposed system of cantilever beams is discussed to study dynamic behaviour of dummy payload. Dimensioning has...
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Augmented speed control scheme of dual induction motors with mutual flux angle control loop
PublicationThis paper proposes an augmented speed control scheme of dual induction motors fed by a five-leg voltage source inverter (VSI) with a common/shared-leg. An additional control loop is proposed here and based on the mutual flux angle – the difference between flux angular positions of the IMs. The main purpose of this research is to minimize the energy losses in the common inverter leg by controlling the mutual flux angle, at equal...
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Quasi-discrete modelling of PMSM phase currents in drives with low switching-to-fundamental frequency ratio
PublicationThis study proposes a new quasi-discrete approach to modelling the permanent magnet synchronous motor (PMSM). The quasi-discrete modelling reflects the impact of continuous rotor movement, which takes place during a control cycle, on the shape of motor current waveforms. This provides much improvement in current modelling accuracy under inverter low switching-to-fundamental frequency operation. The proposed approach may be used...
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Formowanie napięć wyjściowych trójfazowego przekształtnika sieciowego
PublicationW artykule przedstawiono kompensację dwu zasadniczych zjawisk powodujących zniekształcenia prądów fazowych przekształtnika sieciowego. Pierwszym z nich są zniekształcenia napięcia sieci. W celu ich eliminacji zaproponowano uśrednianie za okres podstawowej harmonicznej uchybu regulatora napięcia obwodu pośredniczącego oraz predykcję napięcia sieci. Drugim natomiast są zniekształcenia napięć wyjściowych przekształtnika sieciowego....
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Museum Institutions in Monuments - Positive and Negative Aspects of Adaptation: The New Amber Museum and Museum of Science in Gdansk, Poland
PublicationThe issue of the creation and location of new museums is a current topic. The decision of where and how to create new museum facilities will impact successful function in the future. Museums are either located in newly designed buildings or in existing buildings. In general, existing buildings adapted for museum use are either formally under conservational protection or not. With regard to museum location in preserved monuments,...
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Inline Microwave Filters With N+1 Transmission Zeros Generated by Frequency-Variant Couplings: Coupling-Matrix-Based Synthesis and Design
PublicationA general coupling-matrix-based synthesis methodology for inline Nth-order microwave bandpass filters (BPFs) with frequency-variant reactive-type couplings that generate N+1 transmission zeros (TZs) is presented in this brief. The proposed approach exploits the formulation of the synthesis problem as three inverse nonlinear eigenvalue problems (INEVPs) so that the coupling matrix is built from their sets of eigenvalues. For this...
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On forced vibrations of piezo-flexomagnetic nano-actuator beams
PublicationThe effect of excitation frequency on the piezomagnetic Euler-Bernoulli nanobeam taking the flexomagnetic material phenomenon into consideration is investigated in this chapter. The magnetization with strain gradients creates flexomagneticity. We couple simultaneously the piezomagnetic and flexomagnetic properties in an inverse magnetization. Resemble the flexoelectricity, the flexomagneticity is also size-dependent. So, it has...
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Standing Acoustic Waves and Relative Nonlinear Phenomena in a Vibrationally Relaxing Gas-Filled Resonator
PublicationStanding acoustic waves in one-dimensional resonator filled with vibrationally relaxing gas, are studied. Two regimes of excitation of molecular vibrational degrees of freedom are considered, equilibrium and nonequilibrium. The acoustic energy enlarges with time in the non-equilibrium regime and decreases otherwise before formation of discontinuity. After that, it decreases due to nonlinear absorption and tends to zero in equilibrium...
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Nitrogen and phosphorus compounds in coastal aquifers in Puck municipality area (northern Poland)
Publication1. Groundwater study shows local variations in chemical composition of selected aquifers caused by human impact The diversity is mainly manifested in • time variation of groundwater chemical composition of all analyzed parameters especially in shallow aquifers (Q1) • relationship between t he ground water chemical composition and depth of the aquifer where an inverse concentration distribution occurs higher concentrations are observed...
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Computer animation system based on rough sets and fuzzy logic
PublicationA fuzzy logic inference system was created, based on the analysis of animated motion features. The objective of the system is to facilitate the creation of high quality animation by analyzing personalized styles contained in numerous animations. Sequences portraying a virtual character acting with a differentiating personalized style (natural or exaggerated) and various levels of fluidity were prepared and subjectively evaluated....
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Export diversification and economic development: a dynamic spatial data analysis
PublicationThis paper contributes to the empirical literature on the relationship between ‘export variety’ (export diversification) and economic development by relaxing the assumption of cross-country independence and allowing for spatial diffusion of shocks in observed and unobserved factors. Export variety is measured for a balanced panel of 114 countries (1992-2012) using very detailed information on their exports (HS 6-digit product...
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ADAPTIVE BACKSTEPPING TRACKING CONTROL FOR OVER-ACTUATED DP MARINE VESSEL WITH INERTIA UNCERTAINTIES
PublicationDesigning a tracking control system for an over-actuated dynamic positioning marine vessel in the case of insufficient information on environmental disturbances, hydrodynamic damping, Coriolis forces and vessel inertia characteristics is considered. The designed adaptive MIMO backstepping control law with control allocation is based on Lyapunov control theory for cascaded systems to guarantee stabilization of the marine vessel...
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Text Categorization Improvement via User Interaction
PublicationIn this paper, we propose an approach to improvement of text categorization using interaction with the user. The quality of categorization has been defined in terms of a distribution of objects related to the classes and projected on the self-organizing maps. For the experiments, we use the articles and categories from the subset of Simple Wikipedia. We test three different approaches for text representation. As a baseline we use...
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Synchronized six-step voltage generation in high-speed PMSM drive
PublicationSynchronized voltage generation has already been considered in the context of pulse width modulation (PWM). References prove that synchronized PWM substantially decreases subharmonics in inverter output voltage when operating with low switching-to-fundamental frequency ratio. This paper identifies problems of unsynchronized voltage generation in electric drives under six-step inverter operation. Guidelines for the synchronization...
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Effect of Thermal Shock During Legionella Bacteria Removal on the Corrosion Properties of Zinc-Coated Steel Pipes
PublicationThe purpose of this investigation was to conduct the failure analysis of a water-supply system made from zinc-coated steel. The observed corrosion process had an intense and complex character. The brownish deposits and perforations were present after 2-3 years of exploitation. The electrochemical study based on the Tafel polarization, corrosion potential monitoring, and electrochemical impedance spectroscopy together with microscopic...
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Antifungal Activity of Capridine β as a Consequence of Its Biotransformation into Metabolite Affecting Yeast Topoisomerase II Activity
PublicationIn the last few years,increasing importance is attached to problems caused by fungal pathogens. Current methods of preventing fungal infections remain unsatisfactory. There are several antifungal compounds whichare highly effective in some cases, however, they have limitations in usage: Nephrotoxicity and other adverse effects. In addition, the frequent use of available fungistatic drugs promotes drug resistance....
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Lateral forces determine dimensional accuracy of the narrow‑kerf sawing of wood
PublicationThe shrinking global forest area limits the supply of industrially usable raw resources. This, in combination with the ever‑increasing consumption of timber due to population growth can lead to the lack of a positive balance between the annual volumetric growth and consumption of wood. An important innovation toward increasing environmental and economic sustainability of timber production is to reduce the volume of wood residues...
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The impact of initial and boundary conditions on severe weather event simulations using a high-resolution WRF model. Case study of the derecho event in Poland on 11 August 2017
PublicationPrecise simulations of severe weather events are a challenge in the era of changing climate. By performing simulations correctly and accurately, these phenomena can be studied and better understood. In this paper, we have verified how different initial and boundary conditions affect the quality of simulations performed using the Weather Research and Forecasting Model (WRF). For our analysis, we chose...
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Protective properties of Al2O3 + TiO2 coating produced by the electrostatic spray deposition method
PublicationMechanical resistance of Al2O3 + TiO2 nanocomposite ceramic coating deposited by electrostatic spray deposition method onto X10CrAlSi18 steel to thermal and slurry tests was investigated. The coating was produced from colloidal suspension of TiO2 nanoparticles dispersed in 3 wt% solution of Al2(NO3)3, as Al2O3 precursor, in ethanol. TiO2 nanoparticles of two sizes, 15 nm and 32 nm, were used in the experiments. After deposition,...
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The Influence of External Load on the Performance of Microbial Fuel Cells
PublicationIn this work, the effect of the external load on the current and power generation, as well as on the pollutant removal by microbial fuel cells (MFCs), has been studied by step-wise modifying the external load. The load changes included a direct scan, in which the external resistance was increased from 120 Ω to 3300 Ω, and a subsequent reverse scan, in which the external resistance was decreased back to 120 Ω. The reduction in the...
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Pompownie dużej mocy z falownikiem wędrującym średniego napięcia
PublicationArtykuł zawiera rys rozwoju napędów przekształtnikowych w stacjach pomp, w szczególności regulacji wydatku kilku pomp, po kolei, przez jeden przemiennik częstotliwości. Omówiono podstawy teoretyczne zjawiska pola niestłumionego i napięcia resztkowego silników, które utrudniają szybkie przełączania silnika pompy pomiędzy zasilaniem regulowanym przez falownik a zasilaniem z sieci. Przedstawiono zasady transferu (przełączania) synchronicznego...
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Sprawczość vs wspólnotowość w postrzeganiu zespołów zróżnicowanych kulturowo
PublicationArtykuł dotyczy problematyki postrzegania i oceny zalet i wad pracy w zespołach zróżnicowanych kulturowo, a w szczególności psychospołecznych wymiarów takiej oceny. Wyniki dotychczasowych badań wskazują, że decyzja o możliwości współpracy z innymi ludźmi poprzedzana jest oceną dokonywaną w odniesieniu do dwóch podstawowych wymiarów wartościowania: sprawczości i wspólnotowości. Koncentracja na efektywności działania ukierunkowanego...
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Nitrate and nitrite silver complexes with weakly coordinating nitriles
PublicationSimple system of weak nitrile ligands and silver nitrite/nitrate allowed the formation and isolation of coordination compounds of diverse nuclearity and dimensionality. The extension of the network does not enhance the luminescent properties of the ligands however it gives rise to the new MLCT bands in the visible region.
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Luminance Distribution Measurements in CAVE-Type Virtual Reality Systems
PublicationIn this article, the immerse 3D visualization lab just opened at the Gdańsk University of Technology is presented. The effect of user “immersion,” it such virtual reality systems, is largely dependent on the optical properties of projected images. Luminance distribution of screens was measured and the luminance uniformity was determined and discussed.
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Distinction of clenbuterol intake from drug or contaminated food of animal origin in a controlled administration trial – the potential of enantiomeric separation for doping control analysis
PublicationThe differentiation of clenbuterol abuse and unintentional ingestion by contaminated meat is crucial with respect to the valuation of an adverse analytical finding in human sports doping control. The proportion of the two enantiomers of clenbuterol may serve as potential discriminating parameter. For the determination of the individual enantiomers, specific methods were developed and validated for the different matrices under investigation...
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Przekształtniki tranzystorowe działające w trybie prądu trójkątnego
PublicationPrzekształtniki oparte na węgliku krzemu mogą być analizowane jako źródła napięcia lub prądu niezależnie od topologii przy odpowiednich parametrach filtru wyjściowego. Szczególnie interesujące są falowniki napięcia działające w trybie prądu trójkątnego. W referacie przedstawiono sterowanie trójfazowym falownikiem napięcia posiadającym właściwości źródła prądu. Pokazano, jak dobrać parametry filtru wyjściowego falownika. Oceniono...
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Hardware cryptography coprocessor for system on chip soft processor
PublicationW artykule przedstawiono realizację sprzętową i programową szyfrującejo i deszyfrującego algorytmu AES.Obydwie implementacje zostały zralizowane z wykorzystaniem układu Virtex II i przetestowane. Jako kryterium porónawcze wybrano zużycie zasobów układu oraz wydajność. Realizacja sprzętowa wykonuje operację szyfrowania 2 dekady szybcie niż wersja programowa, ale wymaga pięciokrotnie więcej zasobówIn this paper hardware and software...
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Effect of Axial Porosities on Flexomagnetic Response of In-Plane Compressed Piezomagnetic Nanobeams
PublicationWe investigated the stability of an axially loaded Euler–Bernoulli porous nanobeam considering the flexomagnetic material properties. The flexomagneticity relates to the magnetization with strain gradients. Here we assume both piezomagnetic and flexomagnetic phenomena are coupled simultaneously with elastic relations in an inverse magnetization. Similar to flexoelectricity, the flexomagneticity is a size-dependent property. Therefore,...
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Quadrotor Flight Controller Design Using Classical Tools
PublicationA principal aspect of quadrocopter in-flight operation is to maintain the required attitude of the craft’s frame, which is done either automatically in the so-called supervised flight mode or manually during man-operated flight mode. This paper deals with the problem of flight controller (logical) structure and algorithm design dedicated for the man-operated flight mode. The role of the controller is to stabilise the rotational...
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On the Matano Plane Position in Multicomponent Diffusion Couples
PublicationEven though several methods of diffusion analysis avoid a necessity for the Matano plane determination, the Matano plane locations are of interest in the multicomponent couples and when tracer experiments are performed. The positions of the Matano plane calculated from the concentration profiles should be exactly the same. However, due to experimental errors, the results can differ significantly. In the paper we consider Matano...
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On the Matano Plane Position in Multicomponent Diffusion Couples
PublicationEven though several methods of diffusion analysis avoid a necessity for the Matano plane determination, the Matano plane locations are of interest in the multicomponent couples and when tracer experiments are performed. The positions of the Matano plane calculated from the concentration profiles should be exactly the same. However, due to experimental errors, the results can differ significantly. In the paper we consider Matano...
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Approach for Determination of Functioning of Lower Limb Muscles
PublicationThe purpose of the study is elaboration of approach for determination of functioning of chosen muscles that are essential for gait performance (Tibialis Anterior, Rectus Femoris, Gastrocnemius Medialis, Biceps Femoris). The scope of the study involves the analysis of the symmetric planar motion performing in the sagittal plane of the body by applying planar multibody model and electromyography signals (EMG) registered over normal...
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Measurements of fundamental properties of homogeneous tissue phantoms
PublicationWe present the optical measurement techniques used in human skin phantom studies. Their accuracy and the sources of errors in microscopic parameters’ estimation of the produced phantoms are described. We have produced optical phantoms for the purpose of simulating human skin tissue at the wavelength of 930 nm. Optical coherence tomography was used to measure the thickness and surface roughness and to detect the internal inhomogeneities....
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Modeling the impact of rotor movement on non-linearity of motor currents waveforms in high-speed PMSM drives
PublicationMotor current measurement techniques as well as predictive control algorithms for electric drives rely on an assumption of linear motor currents changes resulting from constant inverter output voltages. Recent research has reported that this assumption does not hold in motors with short electrical time constant, and in drives whose rotor position advances substantially during a control period. This paper proposes a simulation model...
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Zastosowanie modułu symulacji dynamicznej programu CAD w analizie układu napędowego elektronarzędzia
PublicationW referacie przedstawiono analizę mechanicznego układu przeniesienia napędu elektronarzędzia (wyrzynarki elektrycznej) przy zastosowaniu Modułu Symulacji Dynamicznej (MSD) programu Autodesk Inventor (AI). Opracowano modele 3D poszczególnych części elektronarzędzia i połączono je przy zachowaniu tzw. kinematyki odwrotnej. Przeprowadzono analizę wpływu poszczególnych węzłów kinetycznych na przebieg momentu na wale silnika elektrycznego....
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Antioxidant properties of ferrous flavanol mixtures
PublicationInteraction of metal, especially iron ions with flavanols is considered as an important feature of these compounds and is believed to contribute to their both antioxidant and prooxidant properties. The aim of this study was to examine how Fe2+ binding to form a 4:1 (flavanol:Fe2+) mixtures affects the antioxidant properties of flavanols. ABTS∗ scavenging, protection against fluorescence bleaching induced by AAPH and hypochlorite,...
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Oversizing the photovoltaic generator capacity in a micro photovoltaic plant
PublicationA significant part of photovoltaic micro installations in Poland is characterized by photovoltaic generator oversizing in relation to the inverter. The idea of oversizing, however, still raises doubts among some plant owners. In the paper, the energy yield of installation with an oversized and not oversized photovoltaic generator is presented on selected examples, showing the legitimacy of oversizing.
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The multiscalar control of induction motor with the sliding mode controllers
PublicationThe control structure of induction motor is proposed in this paper. The structure of multiscalar control with conventional PI - controllers is well known in literature. The sliding mode multiscalar control (SMMC) conception is presented in this paper. The induction motor is fed by voltage source inverter. Comparison between two multiscalar control method is showed.
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Value of Age Diversity – Declarations and Practice in Polish Organizations
PublicationThe present article relates to management of age diverse teams in organisations and enterprises located in Poland. Managing diversity is an active and conscious process leading not only to a lack of discriminatory conduct but above all to making full use of the potential of the team. The potential resulting from the diversity of knowledge, skills and experience. The diversity of the age of the team members is in fact a differentiation...
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Towards Scalable Simulation of Federated Learning
PublicationFederated learning (FL) allows to train models on decentralized data while maintaining data privacy, which unlocks the availability of large and diverse datasets for many practical applications. The ongoing development of aggregation algorithms, distribution architectures and software implementations aims for enabling federated setups employing thousands of distributed devices, selected from millions. Since the availability of...
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Modeling and simulation of blood flow under the influence of radioactive materials having slip with MHD and nonlinear mixed convection
PublicationRadioactive materials are widely in industry, nuclear plants and medical treatments. Scientists and workers in these fields are mostly exposed to such materials, and adverse effects on blood and temperature profiles are observed. In this regard, objective of the current study is to model and simulate blood based nanofluid with three very important radioactive materials, named as Uranium dioxide (UO2), Thorium dioxide (ThO2) and...
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Invasive Assessment of the Myocardial Microcirculation during Beating Heart Coronary Artery Bypass Grafting
PublicationCoronary artery bypass grafting may be associated with several cardiac complications, including ischemia, acute myocardial infarction, arrhythmias, or hemodynamic instability. Accumulating evidence suggests that well-developed coronary collateral circulation may protect against adverse effects, including myocardial ischemia. Assessment of myocardial microvascular perfusion is, therefore, of great clinical interest in beating heart...
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NADPH Oxidase Gene Polymorphism is Associated with Mortality and Cardiovascular Events in 7-Year Follow-Up
PublicationThe CYBA gene encodes the regulatory subunit of NADPH oxidase, which maintains the redox state within cells and in the blood vessels. That led us to investigate the course of coronary artery disease (CAD) with regards to CYBA polymorphisms. Thus, we recruited 1197 subjects with coronary atherosclerosis and observed them during 7-year follow-up. Three CYBA polymorphisms: c.214C>T (rs4673), c.-932G>A (rs9932581), and c.*24G>A (1049255)...