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Influence of geometrical and operational parameters on tooth wear in the working mechanism of a satellite motor
PublicationThis article describes the phenomena affecting the wear of the rotor of the working mechanism in a hydraulic satellite motor. The basic geometrical relationships that allow the calculation of the coordinates of the points of contact between the satellite and the rotor and the curvature are presented. A method for calculating the number of contacts of the satellite teeth with the rotor teeth and of the satellite teeth with the curvature...
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Innovative Bidirectional Isolated High-Power Density On-Board Charge for Vehicle-to-Grid
PublicationThis paper deals with developing and implementing a bidirectional galvanically isolated on-board charger of a high-power density. The power density of the new charger was 4 kW/kg and 2.46 kW/dm3, and the maximum efficiency was 96.4% at 3.4 kW. Due to the requirement to achieve a high-power density, a single-stage inverter topology was used. Regarding switching losses, due to the topology of the circuit with so-called hard switching,...
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Sounding Mechanism of a Flue Organ Pipe—A Multi-Sensor Measurement Approach
PublicationThis work presents an approach that integrates the results of measuring, analyzing, and modeling air flow phenomena driven by pressurized air in a flue organ pipe. The investigation concerns a Bourdon organ pipe. Measurements are performed in an anechoic chamber using the Cartesian robot equipped with a 3D acoustic vector sensor (AVS) that acquires both acoustic pressure and air particle velocity. Also, a high-speed camera is employed...
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Underwater acoustic communication system using broadband signal with hyperbolically modulated frequency
PublicationThe implementation of reliable acoustic underwater communication in shallow waters is a scientific and engineering challenge, mainly due to the permanent occurrence of the multipath phenomenon. The article presents the concept of a transmission system using a broadband signal with hyperbolically modulated frequency (HFM) to transmit data symbols and synchronize data frames. The simulation tests were carried out in channels with...
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Audio-visual aspect of the Lombard effect and comparison with recordings depicting emotional states.
PublicationIn this paper an analysis of audio-visual recordings of the Lombard effect is shown. First, audio signal is analyzed indicating the presence of this phenomenon in the recorded sessions. The principal aim, however, was to discuss problems related to extracting differences caused by the Lombard effect, present in the video , i.e. visible as tension and work of facial muscles aligned to an increase in the intensity of the articulated...
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The Reactivity of the Imine Bond within Polynuclear Nickel(II) Complexes
PublicationThree novel Ni complexes with the Schiff base ligand 2-methoxy-6-(E-2-pyridyliminomethyl)-phenol (L1) are described. In comparison with the similar 2-(pyridine-2-ylimino-methyl)phenol (pymp), the mode of coordination of L1 is altered due to the presence of methoxy substituent introducing the sterical hindrance. During the synthesis of the complexes, partial hydrolysis of the ligand was observed. Since such immediate hydrolysis...
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Damage Development on the Surface of Nickel Coating in the Initial Period of Erosion
PublicationThe common occurrence of the phenomenon of cavitation in many industries and the multitude of factors affecting the resistance to cavitation erosion of used materials contribute to the search for methods and appropriate parameters of coating application that are able to minimize the effects of erosion. To determine the validity of the developed application parameters and the method used, cavitation studies and microscopic observations...
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Ultrasonic diagnostics of concrete T-beams used in bridge structures
PublicationThis paper describes a method of ultrasonic diagnostics used for prefabricated concrete elements. The studies are focused on the applicability of nondestructive techniques based on impulse and wave packet induced elastic waves for the condition assessment of T-shaped bridge beams. Experimental tests were performed for the prestressed beam used for the superstructure of the viaduct on A1 highway near Toruń. In addition numerical...
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Diffusible hydrogen content in deposited metal of multilayer welded joints
PublicationThe article describes manufacturing technology of multilayer joints in terms of control the diffusible hydrogen content. Diffusible hydrogen content in deposited metal for multilayer welded joints made of covered rutile electrodes or covered cellulosic and basic electrodes was determined. It was found that after four beads, the diffusible hydrogen content decreases in the case of the first technology from 36 ml/100 g to 18 ml/100...
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Subsoil degradation effect in reliability analysis of the jack-up platform structure
PublicationStructural reliability analysis is considered, by FORM and SORM applied to a certain idealized soil-platform structure interaction problem due to cyclic water wave and wind loads. Wave and wind loads are random variables, whereas dead load is deterministic. Load parameters are typical for storm conditions in the Baltic Sea. The soil-structure interaction is idealized as a set of linear translational and rotational springs. Due...
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How to deal with knowledge in small companies? Defining emergent KM approach
PublicationThis paper examines the concept of emergent KM approach in small companies. The origins of consideration are grounded in the theory of strategic management literature and in particular in the distinction between deliberate versus emergent approach towards strategic planning. Using the methodology of case study, we carried out an explorative research to analyse the characteristics of KM approach in two small companies located in...
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The impact of technological and structural changes in the national economy on the labour-capital relations
PublicationThe aim of the research presented in this paper is to present the relations between labour and capital in the national economy, resulting from technological and structural changes taking place in the years 1991 to 2008. The structure of the paper is as follows. It first presents the functional determinants for the Polish economy in 1991-2008 affecting the phenomenon subject to study. Then it presents the preliminary analysis of...
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Influence of vacuum sublimation deposited metal layer thickness on metrological parameters of the amperometric gas sensor with Nafion membrane
PublicationThe paper presents the results of investigation on an influence of vacuum sublimation deposited platinum layer thickness on the signal, sensitivity and response time of a prototype of sulphur dioxide sensor with Nafion membrane. The working electrode was made by vacuum sublimation deposition of platinum on a surface of Nafion membrane. Pt layers deposited changed an initial structure of Nafion membrane and that phenomenon was utilized...
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The Impact of Forms of Buildings on the Air Exchange in Their Environment. Based on the Example of Urban Development in Warsaw
PublicationPossibilities for energy-efficient, natural ventilation of buildings in an urban environment depend on the airflow around them. This chapter deals with the issue of dependence of air exchange in urban spaces on the building forms used in them and on relative position of these buildings. The authors focused on the problem of air stagnation in dense urban development. This phenomenon increases the energy demand of buildings. The...
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Directed percolation effects emerging from superadditivity of quantum networks
PublicationEntanglement-induced nonadditivity of classical communication capacity in networks consisting of quantum channels is considered. Communication lattices consisting of butterfly-type entanglement-breaking channels augmented, with some probability, by identity channels are analyzed. The capacity superadditivity in the network is manifested in directed correlated bond percolation which we consider in two flavors: simply directed and...
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Social Entrepreneurship Research – Challenges, Explanations and Suggestions for the Field Development
PublicationEmploying critical review and reflection on the key literature in the area of entrepreneurship and management studies in social entrepreneurship field, this paper aims to outline the current challenges this field is facing, while introducing related explanations and suggesting required changes. The current field of social entrepreneurship research is at its nascent stage, which is determined by ongoing definitional debates and...
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Material characterisation of biaxial glass-fibre non-crimp fabrics as a function of ply orientation, stitch pattern, stitch length and stitch tension
PublicationDue to their high density-specific stiffnesses and strength, fibre reinforced plastic (FRP) composites are particularly interesting for mobility and transport applications. Warp-knitted non-crimp fabrics (NCF) are one possible way to produce such FRP composites. They are advantageous because of their low production costs and the ability to tailor the properties of the textile to the reinforcement and drape requirements of the application....
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Modeling of Common Mode Currents Induced by Motor Cable in Converter Fed AC Motor Drives
PublicationInvestigation of conducted EMI generation in AC motor fed by pulse width modulated frequency converters requires to consider parasitic capacitances in converters, motor windings and feeding cables to be taken into account. Motor voltage transients and related common mode currents are significantly correlated with resonance effects occurring in load circuits. An analysis of frequency converter load impedance-frequency characteristics...
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Selected problems of decision making modelling in power engineering
PublicationThe paper presents the selected problems of decision making modelling in power engineering specially investment risk evaluation methods. The proposed model can be used in the range programming the development and investing process in power engineering. Decision making problems in power engineering and the evaluation of investment effectiveness in particular are closely related to modelling which relatively accurately reflects...
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Photophysical processes in the selected white organic light-emitting diodes
PublicationThe first part discusses history of organic emitters, the scope of the work, phenomena in molecular systems, types of architectures in OLEDs, types of OLEDs emitting white light with examples from the literaturę and a description of the parameters chcracterizing LEDs. The second part describes materials, production of the samples, the measurement systems and results. In chapter 8.1 the results for the OLEDs based on emission from...
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Size effect at aggregate level in microCT scans and DEM simulation – Splitting tensile test of concrete
PublicationThe paper describes an experimental and numerical study of size effect on concrete cylindrical specimens in splitting tensile test. Own experimental campaign was performed on specimens with 5 various diameters from D = 74, 105, 150, 192 and 250 mm with hardboard loading strips (distributed load according to standard methods) scaled proportionally to the specimen diameter. The crack opening-control system was applied to obtain the...
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Ship weather routing optimization with dynamic constraints based on reliable synchronous roll prediction
PublicationShip routing process taking into account weather conditions is a constrained multi-objective optimization problem and it should consider various optimization criteria and constraints. Formulation of a stability-related, dynamic route optimization constraint is presented in this paper. One of the key objectives of a cross ocean sailing is finding a compromise between ship safety and economics of operation. This compromise should...
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Detection of Anomalies in the Operation of a Road Lighting System Based on Data from Smart Electricity Meters
PublicationSmart meters in road lighting systems create new opportunities for automatic diagnostics of undesirable phenomena such as lamp failures, schedule deviations, or energy theft from the power grid. Such a solution fits into the smart cities concept, where an adaptive lighting system creates new challenges with respect to the monitoring function. This article presents research results indicating the practical feasibility of real‐time...
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Physics augmented classification of fNIRS signals
PublicationBackground. Predictive classification favours performance over semantics. In traditional predictive classification pipelines, feature engineering is often oblivious to the underlying phenomena. Hypothesis. In applied domains such as functional Near Infrared Spectroscopy (fNIRS), the exploitation of physical knowledge may improve the discriminative quality of our observation set. Aims. Give exemplary evidence that intervening the...
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The excitation controller with gain scheduling mechanism for synchronous generator control
PublicationThe power systems, including the synchronous generators and power systems networks, are complex nonlinear systems with configuration and parameters which change through time. That leads to electromechanical oscillations occurring in that system. Thus synchronous generator excitation controller must be capable of providing appropriate stabilization signal over broad range of operating conditions and disturbances. In this paper,...
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Simulation of fluid structure interaction in a novel design of high pressure axial piston pump
PublicationA novel type of an axial, piston-driven high pressure hydraulic pump with variable capacity marks a significant improvement in the area of the hydraulic machinery design. Total discharge from hydrostatic forces eliminates a need for a servomechanism, thus simplifying operation, reducing weight and introducing the possibility of the pump displacement control by computer. PWK-type pumps, invented in the Gdansk University of Technology,...
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Simulation of fluid structure interaction in a novel design of high pressure axial piston hydraulic pump
PublicationA novel type of an axial, piston-driven high pressure hydraulic pump with variable capacity marks a significant improvement in the area of the hydraulic machinery design. Total discharge from hydrostatic forces eliminates a need for a servomechanism, thus simplifying operation, reducing weight and introducing the possibility of the pump displacement control by computer. PWK-type pumps, invented in the Gdansk University of Technology,...
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FTIR spectroscopic and thermogravimetric characterization of ground tyre rubber devulcanized by microwave treatment
PublicationIn this work, the phenomena involved in the microwave devulcanization of ground tyre rubber (GTR) were investigated. Three types of GTR with different content of organic compounds (elastomers, plasticizers, etc.), carbon black and ash have been studied. The chemical structure of GTR before and after a microwave devulcanization process was analyzed by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA)...
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Conditions controlling atmospheric pollutant deposition via snowpack
PublicationSolid precipitation represents a potentially important addition to other measures of deposition. However, an accurate estimate of snowfall amount and pollutant loading is not a trivial matter. There are obvious distinctions between regular precipitation collection and snowpack sampling that represent the cumulative chemistry of bulk deposition. The main goal is to show the most important processes and factors that may influence...
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Nodal models of Pressurized Water Reactor core for control purposes – A comparison study
PublicationThe paper focuses on the presentation and comparison of basic nodal and expanded multi-nodal models of the Pressurized Water Reactor (PWR) core, which includes neutron kinetics, heat transfer between fuel and coolant, and internal and external reactivity feedback processes. In the expanded multi-nodal model, the authors introduce a novel approach to the implementation of thermal power distribution phenomena into the multi-node...
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Modeling of luminance distribution in CAVE-type virtual reality systems
PublicationAt present, one of the most advanced virtual reality systems are CAVE-type (Cave Automatic Virtual Environment) installations. Such systems are usually consisted of four, five or six projection screens and in case of six screens arranged in form of a cube. Providing the user with a high level of immersion feeling in such systems is largely dependent of optical properties of the system. The modeling of physical phenomena plays nowadays...
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If Gravity is Geometry, is Dark Energy just Arithmetic?
PublicationArithmetic operations (addition, subtraction, multiplication, division), as well as the calculus they imply, are non-unique. The examples of four-dimensional spaces, R^4 and (−L/2,L/2)^4, are considered where different types of arithmetic and calculus coexist simultaneously. In all the examples there exists a non-Diophantine arithmetic that makes the space globally Minkowskian, and thus the laws of physics are formulated in terms...
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Electrochemical properties of porous Sr0.86Ti0.65Fe0.35O3 oxygen electrodes in solid oxide cells: Impedance study of symmetrical electrodes
PublicationThis work evaluates porous Sr0.86Ti0.65Fe0.35O3 (STF35) as a possible oxygen electrode material for Solid Oxide Cells. The powder synthesis was performed by solid state method. Characterization included DC electrical conductivity study of sintered bulk samples and impedance spectroscopy study of symmetrical electrodes deposited on gadolinium doped ceria substrates. Measurements were carried out in atmospheres with different pO2...
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NEW SOLUTIONS FOR THE SOLAR CHARGE CONTROLLERS DESIGN FOR OBTAINING TRUE MPP IN PARTLY SHADED PV MODULES
PublicationSoft shading sources such as tree limbs, structural elements of buildings and chimneys, scatter and refract sunlight, significantly reducing the amount of radiation reaching the surface of the module. The hard shadings located directly on the surface (i.e. bird droppings, leaves, snow) tend to stop sunlight completely. These phenomena significantly affects the output characteristics of photovoltaic modules and often contribute...
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Hydrogen Embrittlement and Oxide Layer E ect in the Cathodically Charged Zircaloy-2
PublicationThe present paper is aimed at determining the less investigated effects of hydrogen uptake on the microstructure and the mechanical behavior of the oxidized Zircaloy-2 alloy. The specimens were oxidized and charged with hydrogen. The different oxidation temperatures and cathodic current densities were applied. The scanning electron microscopy, X-ray electron diffraction spectroscopy, hydrogen absorption assessment, tensile, and...
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Experimental Verification of the CFD Model of the Squeeze Film Lifting Effect
PublicationAbstract: The presented study shows the results of the research into the squeeze film levitation phenomena. The system introduced in the investigation is composed of a vibrating surface, air squeeze film, and the surface of the body freely suspended over the film. The use of the CFD (Computational Fluid Dynamics) model used in the system allows us to determine the steady state, periodic behavior of the air film (described by Navier–Stokes,...
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Joint experimental and theoretical study on low-energy elastic electron scattering by gaseous alkynes: Differential cross sections, shape resonances, and methylation effects
PublicationA detailed comparison of experimental and theoretical elastic cross sections for low-energy electron scattering by ethyne, taken earlier in our group by Gauf et al. [Phys. Rev. A 87, 012710 (2013)], and some of its methylated derivatives, propyne, and the isomers 1-butyne and 2-butyne, taken here, are presented. The present differential cross sections were measured at incident electron energies ranging from 1 eV to 30 eV and...
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Magnetic and capacitive couplings influence on power losses in double circuit high voltage overhead transmission line
PublicationPurpose – The paper aims to discuss problems of power and energy losses in a double-circuit overhead transmission line. It was observed from energymeters’ readings, that in such a line, active power losses can be measured as “negative”. The “negative” active power losses appear when the active power injected to the circuit is lower than the active power received at the circuit end. The purpose of this paper is to explain this phenomenon. Theoretical...
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Mentor&Student Research Lab: new type of architectural and urban design workshops, new opportunities, valuable results
PublicationThe space around us has significantly changed during last years. Polish cities have undergone a major transformation following political, economical and social transition [8]. Similar change is noticeable at universities and their educational programmes for architecture and spatial planning students. Nowadays designers and activists tackle completely different problems and have different opportunities than their older colleagues...
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Research on entrepreneurship – the forms of entrepreneurship
PublicationThe aim of this article is to present suggestions for future directions of research on entrepreneurship, with particular emphasis on different forms of entrepreneurship. The suggestions are preceded by a brief review of research on entrepreneurship. The article is theoretical in nature and does not present any own research, although its content is based on multiple years of experience in studying this phenomenon. The forms of entrepreneurship...
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Bi-based halide perovskites: Stability and opportunities in the photocatalytic approach for hydrogen evolution
PublicationIn this study, we successfully prepared Bi-based single perovskites of the A3Bi2I9 type (A = Cs, Rb, MA, FA), and, for the first time, attempted to experimentally obtain double perovskites Cs2B’BiI6 type (B′ = Ag, Au, In, Cu). Despite the premises available in theoretical studies, our research has proven the impossibility of the existence of double perovskites of this type. Nevertheless, both types of obtained materials were subjected...
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Linking Fashion and Tourism: From Body to Clothing and Lifestyle
PublicationThere are many profound links between fashion and tourism. This chapter provides a critical reflection, mainly from a philosophical, historical, and linguistic perspective, on the dynamic relationship and parallel evolution between these two sectors. It explains how their intercon nectedness form and mirror contemporary society. This chapter classifies the connections between the two, starting with the person, her body, and the...
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Quantum strategies for rendezvous and domination tasks on graphs with mobile agents
PublicationThis paper explores the application of quantum nonlocality, a renowned and unique phenomenon acknowledged as a valuable resource. Focusing on an alternative application, we demonstrate its quantum advantage for mobile agents engaged in specific distributed tasks without communication. The research addresses the significant challenge of rendezvous on graphs and introduces a distributed task for mobile agents grounded in the graph...
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Zmienność termicznego charakteru okresów zimowych w Polsce i jej przyczyny
PublicationPraca przybliża problematykę funkcjonowania fenomenu klimatycznego Oscylacji Północnego Atlantyku (Norh Atlantic Oscillation – NAO) oraz omawia jej wpływ na kształtowanie charakteru termicznego zim (grudzień – marzec) na obszarze Polski. Zmiana faz NAO z w przewadze ujemnych na w przewadze dodatnie, jaka nastąpiła w latach 1987-1989 spowodowała, że po roku 1989 obserwuje się w Polsce znaczne złagodzenie stopnia ostrości zim.
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Funkcjonowanie zespołów napędu hydraulicznego maszyn w niskich temperaturach otoczenia
PublicationW pracy przedstawiono cztery warianty klasyfikacji rozruchów oziębionego napędu hydraulicznego. Pierwsza sytuacja dotyczy zagadnienia, w którym wszystkie zespoły układu napędowego wraz z olejem mają taką samą niską temperaturę podczas rozruchu. Pozostałe warianty odnoszą się do rozruchu w warunkach szoku termicznego wywołanych zasilaniem ciepłym czynnikiem roboczym oziębionych zespołów hydraulicznych. Rozruch zespołów...
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Wpływ właściwości cieczy hydraulicznej na wartość skoków ciśnienia w komorach pomp tłoczkowych osiowych
PublicationPublikacja dotyczy badań skoków ciśnienia w komorach roboczych pomp tłoczkowych osiowych. Skupiono się w nim na wpływie właściwości cieczy hydraulicznej na wartość skoków ciśnienia. Przeanalizowano wpływ takich parametrów jak: -gęstość, -lepkość, -ściśliwość, -zapowietrzenie. Do określenia wpływu właściwości cieczy na skoki ciśnienia wykorzystano badania laboratoryjne i symulacje komputerowe.
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Odkrywanie nadwodnego wizerunku miast delty Wisły
PublicationArtykuł odnosi się do specyficznego obszaru funkcjonalnego, którego tożsamość opierała się przede wszystkim na relacji z wodą – w większych miastach portowych, a także powiązanych z nimi mniejszych miejscowościach. Opisuje zjawisko wykorzystania i reinterpretacji potencjału bogatej sieci hydrograficznej do odbudowania tożsamości przestrzennej po gwałtownych wydarzeniach XX wieku. Cytowane studia przypadków są zróżnicowane ze względu...
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Allergic Reactions as a Defense of the Organism to the Influence of Implants Components Made of Stainless Steel
PublicationDue to the increasing number of cases of hypersensitivity caused by direct contact with metals, as well as the increasing demand for implants in humans all ages numerous studies on the effects of the impact of implant components are being carried out. The paper presents the phenomenon of etiology of allergy in general terms and in relation to the biomaterials used in medicine. There have been characterized in terms of impact on...
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Asymptomatic Bacteriuria in Kidney Transplant Recipients—A Narrative Review
PublicationUrinary tract infections (UTIs) are the most prevalent complications in kidney transplant (KTx) recipients. The most frequent finding in this group of patients is asymptomatic bacteriuria (ASB). Here, we provide an overview of the available evidence regarding ASB in KTx recipients, including its etiopathology, clinical impact and management. There is a growing body of evidence from clinical trials that screening for and treating...
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Allergic reactions as a defense of the organism to the influence of implants components made of stainless steel
PublicationDue to the increasing number of cases of hypersensitivity caused by direct contact with metals, as well as the increasing demand for implants in humans all ages numerous studies on the effects of the impact of implant components are being carried out. The paper presents the phenomenon of etiology of allergy in general terms and in relation to the biomaterials used in medicine. There have been characterized in terms of impact on...