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One Year Evaluation of Material Properties Changes of Polylactide Parts in Various Hydrolytic Degradation Conditions
PublikacjaBiodegradable biocompatible materials are widely used in medical applications. Determining the possibility of using biodegradable materials depends on determining the changes in their parameters over time due to degradation. The current scientific research on biodegradable materials has presented results based on research methods characterized by the different geometry and cross-section size of the specimen, type of degradation...
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Bringing Bathymetry LiDAR to Coastal Zone Assessment: A Case Study in the Southern Baltic
PublikacjaOne of the major tasks in environmental protection is monitoring the coast for negative impacts due to climate change and anthropopressure. Remote sensing techniques are often used in studies of impact assessment. Topographic and bathymetric procedures are treated as separate measurement methods, while methods that combine coastal zone analysis with underwater impacts are rarely used in geotechnical analyses. This study presents...
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Charge Transfer, Complexes Formation and Furan Fragmentation Induced by Collisions with Low-Energy Helium Cations
PublikacjaThe present work focuses on unraveling the collisional processes leading to the fragmentation of the gas-phase furan molecules under the He+ and He2+ cations impact in the energy range 5–2000 eV. The presence of different mechanisms was identified by the analysis of the optical fragmentation spectra measured using the collision-induced emission spectroscopy (CIES) in conjunction with the ab initio calculations. The measurements of...
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Inhomogeneity of low-noise wearing courses evaluated by tire/road noise measurements using the close-proximity method
PublikacjaPerforming numerous analyses of tire/road noise measurements on low-noise pavements during the last several years, the authors observed significant inhomogeneity of the wearing course in numerous cases, while similar problems were almost non-existent when dense pavements were measured. Three main causes of low-noise pavement inhomogeneity can be defined. The first one is imperfections in the technology used for asphalt mix production...
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Challenges of overcoming ageism towards elderly people in healthcare context
PublikacjaRESEARCH OBJECTIVE: The purpose of the paper is to analyse the impact ageism may have on providing healthcare to elderly people. THE RESEARCH PROBLEM AND METHODS: The article investigates the consequences of ageism in medical settings, where the elderly are particularly vulnerable to discrimination, distinguishing ageism from appropriate practice variation as well as giving suggestions to improve the situation. The paper analyses...
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Pedestrian Safety at Midblock Crossings on Dual Carriageway Roads in Polish Cities
PublikacjaRoad crossings across two or more lanes in one direction are particularly dangerous due to limited sight distance and high vehicle speeds. To improve their safety, road authorities should provide safety treatments. These may include additional measures to reduce speed and narrow the road cross-section and the introduction of active pedestrian crossings. Equipped with flashing lights activated automatically when a pedestrian is...
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INVESTIGATIONS OF THE EMISSION CHARACTERISTICS OF A DUAL-FUEL GAS TURBINE COMBUSTION CHAMBER OPERATING SIMULTANEOUSLY ON LIQUID AND GASEOUS FUELS
PublikacjaT his study is dedicated to investigations of the working process in a dual-fuel low-emission combustion chamber for a floating vessel’s gas turbine. As the object of the research, a low-emission gas turbine combustion chamber with partial premixing of fuel and air inside the outer and inner radial-axial swirls was chosen. The method of the research is based on the numerical solution of the system of differential...
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Multi-Temporal Analysis of Changes of the Southern Part of the Baltic Sea Coast Using Aerial Remote Sensing Data
PublikacjaUnderstanding processes that affect changes in the coastal zone and the ability to predict these processes in the future depends on the period for which detailed monitoring is carried out and on the type of coast. This paper analyzes a southern fragment of the Baltic coast (30 km), where there has been no anthropogenic impact (Slowinski National Park). The study was carried out covering a time interval of 65 years. Historic and...
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Evaluating the risk of endometriosis based on patients’ self-assessment questionnaires
PublikacjaBackground Endometriosis is a condition that significantly affects the quality of life of about 10 % of reproductive-aged women. It is characterized by the presence of tissue similar to the uterine lining (endometrium) outside the uterus, which can lead lead scarring, adhesions, pain, and fertility issues. While numerous factors associated with endometriosis are documented, a wide range of symptoms may still be undiscovered. Methods In...
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Preliminary results from HEDGEHOG REXUS Project - sounding rocket experiment on accelerations, vibrations and heat flow
PublikacjaAs access to space conditions becomes more available, both technically and economically, scientists' interest in launching finer and more sophisticated experiments grows. This applies now more than ever to fragile by nature biological and chemical experiments. To be qualified for launch, such experiments need to be carefully tested prior to the event. The tests should represent actual launch conditions as closely and in as detailed...
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Low-cost performance-driven modelling of compact microwave components with two-layer surrogates and gradient kriging
PublikacjaUtilization of electromagnetic (EM) simulation tools has become indispensable for reliable evaluation of microwave components. As the cost of an individual analysis may already be considerable, the computational overhead associated with EM-driven tasks that require massive simulations (e.g., optimization) may turn prohibitive. One of mitigation methods is the employment of equivalent network models. Yet, they are incapable of accounting...
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Design and material selection for a patient transport device in field hospitals
PublikacjaACKGROUND: A major cause of patient and hospital worker injuries occurs transferring patients between two planes. The main aim of this paper was to propose a design of patient’s lift and transfer apparatus for use in field hospitals. The assumption was to design lightweight, durable and ergonomic device using innovative material. The authors concentrated on partial elimination of manual lifting in order to device could work both...
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Analysis of diagnostic informativeness of the exhaust temperature of a naval gas turbine
PublikacjaThe conducted investigations aimed to carry out an analysis of the possibility that the failures identification in the automatic control system of a gas turbine engine could be worked out on the basis of measurements of the exhaust stream temperature behind the gas generator. The exhaust temperature represents a basic control parameter, enabling technical state evaluation of the engine within the operation process, which is observed...
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Advanced Oxidation Processes for the Treatment of Contaminants of Emerging Concern
PublikacjaThe application of contaminants of emerging concern (CEC) such as pharmaceuticals and personal care products (PPCPs), pesticides, plasticizers, endocrine disruptors, surfactants, flame retardants and polycyclic aromatic hydrocarbons (PAHs) became an indispensable requirement of the current era. Although the CEC are useful for wide-spectrum purposes, they can also result in undesirable effects on human health and other animals....
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The effect of road restraint systems on the level of road safety - Polish experience
PublikacjaRoadside accidents happen when a vehicle runs off the road. The majority of these accidents are very severe because leaving the road is usually followed by hitting a solid obstacle (tree, pole, support, culvert front wall, barrier). Roadsides are some of the most important issues of road safety. They have been studied for years to identify roadside hazards and the effectiveness of road safety measures such as restraint systems....
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Assessment of the Relationship between the Shape of the Lateral Meniscus and the Risk of Extrusion Based on MRI Examination of the Knee Joint
PublikacjaBackground Meniscus extrusion is a serious and relatively frequent clinical problem. For this reason the role of different risk factors for this pathology is still the subject of debate. The goal of this study was to verify the results of previous theoretical work, based on the mathematical models, regarding a relationship between the cross-section shape of the meniscus and the risk of its extrusion. Materials and Methods Knee...
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Effects of preheating on laser beam–welded NSSC 2120 lean duplex steel
PublikacjaDuplex stainless steels show sustainable alternative for the conventional austenitic grades, with higher strength, higher resistance against stress corrosion cracking, and lower purchase cost. Thus, duplex stainless steel gains more attention in construction, oil and gas, and chemical industries. Among duplex stainless steels, low nickel and low molybdenum alloyed lean duplex stainless steel are a cost-efective substitution of...
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Complex multidisciplinary optimization of turbine blading systems
PublikacjaThe paper describes the methods and results of direct optimization of turbine blading systems using a software package Opti_turb. The final shape of the blading is obtained from minimizing the objective function, which is the total energy loss of the stage, including the leaving energy. The current values of the objective function are found from 3D RANS computations (from a code FlowER) of geometries changed during the process...
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THE INFLUENCE OF POLYMER STRIPS IN REDUCTION OF A STEEL GRANDSTAND VIBRATIONS
PublikacjaGrandstands are types of structures commonly used during sport events or music concerts. Dynamic loads generated by crowd movement may have significant influence on human perception as well as may lead to the destruction of a structure. Lighter and more slender structural steel members are more easily excitable by spectators. If the synchronized movement is tuned with the natural frequency of the affected part of the structure,...
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Treated wasetewater as a source of humic substances in surface waters
PublikacjaHumic substances impose substantial effect on the aquatic environment as well as the water organisms and human health. Among other features, the humic acids determine organoleptic properties of surface waters. Therefore explanation of the origin and properties of humic acids in surface waters is one of the priorities of water technology.Recently it was pointed out that in the wastewater treatment process organic compounds characterized...
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Analysis of cyclone separator solutions depending on spray ejector condenser conditions
PublikacjaThe core design strategy for minimizing CO2 emissions in gas power plant entails combining a spray ejector condenser (SEC) and separator to accomplish steam condensation and CO2 purification. This innovative process involves direct-contact condensation of steam with CO2, facilitated by interaction with a subcooled water spray, along with a cyclone separator mechanism intended for generating pure CO2. The investigation of the SEC...
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Why are trees still such a major hazard to drivers in Poland?
PublikacjaRoadside trees are one of Poland's most serious road safety issues. Since 2009 more than 2800 people have been killed as a result of tree collisions; this represents about 15% of all of Poland's accident fatalities between 2009 and 2013. In some of the country's regions striking a tree caused more than 30% of all road accident fatalities. With no proper regulations, guidelines or examples of good practice, roadside environments...
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Bridge Non-Destructive Measurements Using a Laser Scanning during Acceptance Testing: Case Study
PublikacjaOwing to the recent proliferation of inventory works on roads and railways, bridge acceptance tests have increased exponentially. These tests’ results are often misinterpreted owing to the use of various measuring equipment types, rendering integrated interpretation problematic. It is also problematic that adjusting the measurement method is difficult when the structure’s response to load is uncertain. Therefore, it is important...
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Direct-contact condensation from vapour- gas mixture in a spray ejector condenser for negative CO2 power plant
PublikacjaDirect-contact condensation of vapour containing the inert gas on a spray of subcooled liquid exists in a number of technical applications. For example, it may be found in the nuclear industry (e.g. pressurized jet under normal operating conditions, in safety analyses) or in the chemical industry (e.g. mixing-type heat exchanger, degasser, sea water desalting). The problem is also essential to modelling and analysis of some...
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Machine-Learning-Powered EM-Based Framework for Efficient and Reliable Design of Low Scattering Metasurfaces
PublikacjaPopularity of metasurfaces has been continuously growing due to their attractive properties including the ability to effectively manipulate electromagnetic (EM) waves. Metasurfaces comprise optimized geometries of unit cells arranged as a periodic lattice to obtain a desired EM response. One of their emerging application areas is the stealth technology, in particular, realization of radar cross section (RCS) reduction. Despite...
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Shoreline Extraction Based on LiDAR Data Obtained Using an USV
PublikacjaThis article explores the use of Light Detection And Ranging (LiDAR) derived point clouds to extract the shoreline of the Lake Kłodno (Poland), based on their geometry properties. The data collection was performed using the Velodyne VLP‐16 laser scanner, which was mounted on the HydroDron Unmanned Surface Vehicle (USV). A modified version of the shoreline extraction method proposed by Xu et al. was employed, comprising of the following...
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Experimental study on earthquake-induced pounding between steel structures
PublikacjaPounding between adjacent structures has been repeatedly observed during major earthquakes. The phenomenon may cause some local damage at the points of interactions, it may also lead to substantial destruction, permanent deformations or total collapse of colliding structures. The effects of earthquake-induced structural pounding have been studied for more than three decades now. However, most of the studies concerned masonry as...
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A novel concept of enhanced direct-contact condensation of vapour- inert gas mixture in a spray ejector condenser
PublikacjaAn analytical model of direct steam condensation (DCC) in the novel idea of spray ejector condenser (SEC) in the presence of inert gas has been developed. It is based on continuity, momentum and energy equations for the steam-carbon dioxide mixture and direct contact condensation mechanisms due to heat transfer and concentration. Crucial in the process of DCC is atomisation of the motive fluid in the ejector. The effect of atomised...
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Electron-scattering cross sections for selected alkyne molecules: Measurements and calculations
PublikacjaWe report cross-section results from experimental and theoretical studies on electron collisions with 1-butyne (HC≡C–CH2CH3) and acetylene (HC≡CH) molecules and from computations for a propyne (HC≡C–CH3) molecule. Absolute grand -total electron-scattering cross sections (TCSs) were measured at impact energies ranging from about 0.5 to 300 eV using the linear electron-transmission method. The TCS energy curve for 1-butyne has a...
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Cost-Efficient Two-Level Modeling of Microwave Passives Using Feature-Based Surrogates and Domain Confinement
PublikacjaA variety of surrogate modelling techniques has been utilized in high-frequency design over the last two decades. Yet, the curse of dimensionality still poses a serious challenge in setting up re-liable design-ready surrogates of modern microwave components. The difficulty of the model-ing task is only aggravated by nonlinearity of circuit responses. Consequently, constructing a practically usable surrogate model, valid across...
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Flow distribution and heat transfer in minigap and minichannel heat exchangers during flow boiling
PublikacjaThe topic of boiling heat transfer in miniscale geometries has focused the ever increasing interest of researchers in recent years. However, most of the works are related to mini- and microchannels and much less to minigaps. Meanwhile, minigaps allow for more comprehensive experimental studies, i.e. flow visualisations due to the flat, two-dimensional configuration of the flow. The results of the experimental investigations of...
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Guided waves for nondestructive diagnostics of embedded waveguides
PublikacjaThe thesis concentrates on comprehensive theoretical, numerical and experimental analysis of guided wave propagation in bars embedded in concrete or mortar. The investigations are focused on a particular type of objects representing a laboratory model of a ground anchor. Complex description of wave propagation phenomena in partially embedded bars is given and its application in...
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Pedestrian Safety in Road Traffic in Poland
PublikacjaEvery third road accident in Poland involves a pedestrian as a participant or, most of the time, a casualty. Pedestrian accidents are usually the result of complex situations and the outcome of a number of factors related to driver and pedestrian behaviour and road infrastructure. Safety depends largely on how well the traffic condition is perceived and on visibility in traffic. The paper presents the results of analyses of methodologies...
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Dimensionality-Reduced Antenna Modeling with Stochastically Established Constrained Domain
PublikacjaOver the recent years, surrogate modeling methods have become increasingly widespread in the design of contemporary antenna systems. On the one hand, it is associated with a growing awareness of numerical optimization, instrumental in achieving high-performance structures. On the other hand, considerable computational expenses incurred by massive full-wave electromagnetic (EM) analyses, routinely employed as a major design tool,...
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Mechanical strength of stems in aquatic macrophytes
PublikacjaSummary: In populations of submerged macrophytes, individuals are selected in terms of resistance to the effect of hydrodynamic forces. The aim of this study was to check whether individuals growing in river water are more tensile and bending resistant than plants occurring in places not exposed to flow stress. We determined the ultimate tensile strength of stems in four macrophyte species, Potamogeton natans, P. pectinatus, Batrachium...
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Ammonium and potassium vanadates: synthesis, physicochemical characterization, and applications
PublikacjaThis doctoral thesis is devoted to the synthesis and investigation of ammonium/potassium vanadates, which constitute an interesting group of materials due to their potential applications in electrochemical devices and photocatalysis. The scope of the conducted experimental work included the synthesis of ammonium/potassium vanadates, their physicochemical characterization using various methods (spectroscopy, microscopy, thermal...
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Cold recycled mixtures for binder courses - laboratory evaluation of mechanical properties
PublikacjaCold recycled mixtures composed with cement and bituminous emulsion are nowadays commonly used material for base layer. Typical pavement with cold recycled mixtures usually consists of two asphalt courses (wearing and binding course) constructed over cold recycled base. Therefore the next step in cold recycling is possibility of design of binding courses with recycled materials, but with potential to obtain high quality mixtures...
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Modeling of Passive and Forced Convection Heat Transfer in Channels with Rib Turbulators
PublikacjaThe main goal of the research presented in this paper was the experimental and numerical analysis of heat enhancement and aerodynamic phenomena during air flow in a channel equipped with flow turbulators in the form of properly configured ribs. The use of ribs intensifies the heat transfer and at the same time increases not only the flow resistance but also the energy costs. Therefore, designing modern heat exchangers with optimal...
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The dependence of linear viscoelasticity limits of cold-recycled mixtures on time of curing and compaction method
PublikacjaCold-recycled mixtures are currently among the most widely used and investigated methods that enable recycling of old pavement structures in an environmentally friendly manner. Upon milling, the old pavement structure – whose gradation can be improved with addition of virgin aggregate – is mixed and compacted at ambient temperature. The main binding agents are bituminous emulsion and cement. Due to their dual binding behaviour,...
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Political Sources of Government Redistribution in High-Income Countries
PublikacjaIn cross-national empirical work on income inequality and government redistribution, the greatest emphasis has been on the extremes of the income scale. Less work has been done on groups that are neither rich nor poor—the middle class. The lack of attention to this group is unfortunate for several reasons. Most obviously, the middle class, if defined as the three middle income quintile groups, is by far the largest income group,...
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Prediction of ship resistance with the use of Full-scale CFD simulations
PublikacjaIn recent years, the IMO has introduced new regulations to reduce the negative impact of ships on the natural environment. A particularly important step forcing technological innovations is the increasing requirement of ship energy efficiency. It is expressed by the Energy Efficiency Design Index (EEDI). Another important step towards green shipping is rising the required quality of fuel used for propulsion, so called Tier limits....
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Deep learning techniques for biometric security: A systematic review of presentation attack detection systems
PublikacjaBiometric technology, including finger vein, fingerprint, iris, and face recognition, is widely used to enhance security in various devices. In the past decade, significant progress has been made in improving biometric sys- tems, thanks to advancements in deep convolutional neural networks (DCNN) and computer vision (CV), along with large-scale training datasets. However, these systems have become targets of various attacks, with...
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Koncepcja zdalnego sterowania i monitoringu urządzeń trakcyjnych z wykorzystaniem technologii teleinformatycznych
PublikacjaAdvancement in wireless communication enables engineers to apply sophisticated and relatively inexpensive technologies in new fields of industry, which were previously designated solely to wire-based solutions. One of those fields is railway transportation system. In effect of a high reliability and safety demands, this area was resistive to new technologies. Nowadays, increased security and reliability of wireless sensor networks...
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Deep convolutional neural network for predicting kidney tumour malignancy
PublikacjaPurpose: According to the statistics, up to 15-20% of removed solid kidney tumors turn out to be benign in postoperative histopathological examination, despite having been identified as malignant by a radiologist. The aim of the research was to limit the number of unnecessary nephrectomies of benign tumors. Methods or Background: We propose a machine-aided diagnostic system for kidney...
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Tensile and flexural moduli for human orbital wall bones – comparative study
PublikacjaThe main aims of the current research were: (1) to analyze in detail the tensile modulus and ultimate tensile strength (UTS) of orbital wall bones separately for the left and right orbit of the same cadaver and (2) to compare the obtained results with a flexural modulus of the left and right orbit reported earlier by A. C. van Leeuwen et al. [14]. A set of 54 specimens of orbital superior and/or medial walls harvested from 16 human...
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Design of High-Performance Scattering Metasurfaces through Optimization-Based Explicit RCS Reduction
PublikacjaThe recent advances in the development of coding metasurfaces created new opportunities in realization of radar cross section (RCS) reduction. Metasurfaces, composed of optimized geometries of meta-atoms arranged as periodic lattices, are devised to obtain desired electromagnetic (EM) scattering characteristics. Despite potential benefits, their rigorous design methodologies are still lacking, especially in the context of controlling...
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Road Infrastructure Safety Management in Poland
PublikacjaThe objective of road safety infrastructure management is to ensure that when roads are planned, designed, built and used road risks can be identified, assessed and mitigated. Road transport safety is significantly less developed than that of rail, water and air transport. The average individual risk of being a fatality in relation to the distance covered is thirty times higher in road transport that in the other modes. This is...
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Safety PL - a support tool for Road Safety Impact Assessment
PublikacjaPublished on 19 November 2008, the European Union's Directive 2008/96/EC is one of the most important EU documents setting out a road safety orientation, in particular, road infrastructure safety management. It identifies four main areas of activity: road safety impact assessment, road safety audit, ranking of high accident concentration sections and network safety ranking and road infrastructure safety inspection. The Directive...
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Epigenetic regulation and regeneration: the search for differentially methylated genes in the MRL mouse
PublikacjaThe MRL mouse is an inbred laboratory strain, which was developed in the 60’s of the 20th century and has been extensively used as a model of lupus erythematosus. The regenerative abilities of the strain were discovered in the 90' when the MRL mouse was shown to close 2 mm hole punches made in the ear pinnae four weeks after injury without scarring. The phenomenon has not been observed in other mouse strains, where the holes...
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Changes in psychological distress among Polish medical university teachers during the COVID-19 pandemic
PublikacjaOur study aims to update knowledge about psychological distress and its changes in the Polish group of academic medical teachers after two years of a global pandemic. During the coronavirus disease, teachers were challenged to rapidly transition into remote teaching and adapt new assessment and evaluation systems for students, which might have been...