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Simultaneous grouping and ranking with combination of SOM and TOPSIS for selection of preferable analytical procedure for furan determination in food
PublicationNovel methodology for grouping and ranking with application of self-organizing maps and multicriteria decision analysis is presented. The dataset consists of 22 objects that are analytical procedures applied to furan determination in food samples. They are described by 10 variables, referred to their analytical performance, environmental and economic aspects. Multivariate statistics analysis allows to limit the amount of input...
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Laboratory station for research of the innovative dry method of exhaust gas desulfurization for an engine powered with residual fuel
PublicationContemporary methods of exhaust gas desulfurization in marine engines are all expensive methods (4-5 million euro). This is, among other reasons, due to the limited market audience, but primarily due to the monop-olized position of manufacturers offering fabrication and assembly of this type of marine ship installations. Proposed as part of a research project financed by the Regional Fund for Environmental Protection and Maritime...
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Persistent organic pollutants (POPs) as an indicator of surface water quality in the vicinity of the Polish Polar Station, Horsund
PublicationSurface waters were collected in the vicinity of the Polish Polar Station in Hornsund (Svalbard) to determine their concentration of various persistent organic pollutants (POPs), such as polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). In addition, parameters such as pH, SEC and TOC were measured. In total, 15 samples of lake water from and 15 samples of stream water were analysed. The sampling took...
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Glutathione-mediated conjugation of anticancer drugs: an overview of reaction mechanisms and biological significance for drug detoxification and bioactivation.
PublicationThe effectiveness of many anticancer drugs depends on the creation of specific metabolites that may alter their therapeutic or toxic properties. One significant route of biotransformation is a conjugation of electrophilic compounds with reduced glutathione, which can be non-enzymatic and/or catalyzed by glutathione-dependent enzymes. Glutathione usually combines with anticancer drugs and/or their metabolites to form more polar...
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First evaluation of wastewater discharge influence on marine water contamination in the vicinity of Arctowski Station (Maritime Antarctica)
PublicationIn Antarctica,waste is generatedmainly during scientific research programmes and related logistics. In this study, the impact ofwastewater on the western shore of Admiralty Baywas investigated during austral summer in 2017 and 2019. A range of physicochemical parameters and the presence of selected trace metals, formaldehyde and different groups of surfactants were determined in wastewater coming from Arctowski Station and in nearby coastal...
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Convenient Synthesis of Functionalized Unsymmetrical Vinyl Disulfides and Their Inverse Electron-Demand Hetero-Diels-Alder Reaction
PublicationThe simple, convenient, and efficient methods for the preparation of unsymmetrical vinyl disulfides with additional functional groups under mild conditions with moderate to high yields were designed. The developed methods include the reaction of S-vinyl phosphorodithioate with thiotosylates or S-vinyl thiotosylate with thiols. The designed methods allow for the synthesis of unsymmetrical vinyl disulfides with additional functionalities...
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Cross-layer integration of network mechanisms for increasing efficiency of multimedia session support in IEEE 802.11s environment
PublicationWith an IEEE 802.11 wireless networks operating in Point-to-Multipoint mode being the most popular WLAN access technology employed today, it can be expected that a Wireless Mesh Network (WMN) based on the technology can provide significant advantages for such network systems. The IEEE 802.11s standard amendment provides the comprehensive set of mechanisms required to implement and deploy a WMN utilizing this widely popular technology....
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A decision-making system supporting selection of commanded outputs for a ship's propulsion system with a controllable pitch propeller
PublicationThe ship's operators have to make decisions regarding the values of commanded outputs (commanded engine speed and pitch ratio) which ensure maximum vessel speed and minimum fuel consumption. Obviously, the presented decision problems are opposed. Therefore, there is a need for a compromise solution that enables more flexible vessel voyage planning. This paper deals with development of a computer-aided system supporting selection...
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Trust Dynamics Analysis of CTR Scheme Subversion under Virtual Anonymity and Trust-Unaware Partner Selection
PublicationWe propose a framework to study Markovian trust value dynamics in a centralized Computational Trust and Reputation (CTR) scheme under trust-unaware partner selection using a mean-value approximation. Analytically founded answers are sought to questions like: Can dishonest agents subvert the CTR scheme (i.e., acquire higher trust values than honest agents)? Is indirect reciprocity incentivized? Is there a qualitative impact of a...
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Investigations of local/global buckling of cylindrical metal silos with corrugated sheets and open-sectional column profiles
PublicationArtykuł zajmuje się problemem lokalnego/globalnego wyboczenia w cylindrycznych metalowych silosach z blachy falistej z otwartymi cienkościennymi profilami słupowymi. Obliczenia wykonano w ramach liniowej teorii bifurkacji stosując metodę elementów skończonych w programie ABAQUS. Zbadano obszernie wpływ różnych parametrów (średnica i wysokość silosów, grubość blachy falistej, wielkość fali blachy, rozstaw słupów, przekrój słupów)...
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Labellum and gynostemium micromorphology in Polystachya (Orchidaceae)
PublicationPolystachya is a large, pantropical orchid genus of 200 species, most of which occur as epiphytes in sub-saharan Africa. The three-lobed labellum of most Polystachya species possesses a fleshy callus and various types of trichomes and papillae. In this paper, we present the results of micromorphological studies on the labellum of 20 species, representing eight of the 13 sections in the genus, using scanning electron microscopy...
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Low-energy positron scattering from gas-phase benzene
PublicationIn this paper we are presenting calculations of the elastic cross section of positrons with gas-phase benzene for the energy range from 0.25 eV to 9.0 eV. The calculations are done with the molecular R-matrix method for positron-scattering from poly-atomic molecules using a scaling factor to scale the electron-positron interaction. The scaling factor influences the position of the poles of the R-matrix. We adjust the scaling factor...
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Solvation of ionic liquids based on N-alkyl-N-methylmorpholinium cations in N,N-dimethylformamide and dimethyl sulfoxide – A volumetric and acoustic study
PublicationApparent molar volumes and molar isentropic compressibilities for N-ethyl-N-methylmorpholinium and N-decyl-N-methylmorpholinium tetrafluoroborates in N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) have been determined from density and speed of sound measurements over the temperature range T = (298.15, 303.15, 308.15, 313.15, 318.15 and 328.15) K at experimental pressure p = 0.1 MPa. This data has been used to calculate...
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Effect of ionic size of dopants on the lattice structure, electrical and electrochemical properties of La2−xMxNiO4+δ (M = Ba, Sr) cathode materials
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Separation of nicotinic acid and its structural isomers using 1-ethyl-3-methylimidazolium ionic liquid as a buffer additive by capillary electrophoresis
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Determination of methylcyclopentadienyl-manganese tricarbonyl in gasoline and water via ionic-liquid headspace single drop microextraction and electrothermal atomic absorption spectrometry
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The antagonistic role of chaotropic hexafluorophosphate anions and imidazolium cations composing ionic liquids applied as phase additives in the separation of tri-cyclic antidepressants
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Interactions of N-alkyl-N-methylmorpholinium based ionic liquids with acetonitrile studied by density and velocity of sound measurements and molecular dynamics simulations
PublicationMorpholinium-based ionic liquids (ILs) and their mixtures with polar co-solvents are an interesting class of emerging electrolytes in electrochemistry that is relatively poorly studied. In this work, densities and sound velocities of four ILs, N-ethyl-N-methylmorpholinium tetrafluoroborate, N-butyl-N-methylmorpholinium tetrafluoroborate, N-octyl-N-methylmorpho-linium tetrafluoroborate and N-decyl-N-methylmorpholinium tetrafluoroborate...
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Polymer-free cubosomes for simultaneous bioimaging and photodynamic action of photosensitizers in melanoma skin cancer cells
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Synergistic action of extracts from carnivorous plants and synthetic peptides against plant pathoghenic bacteria
Publicationw pracy przedstawiono rezultaty badań nad sprawdzeniem aktywności przeciwbakteryjnej ekstraktów z roślin Drosera capensis i Dionaea muscipula w połączeniu z dwoma syntetycznymi peptydami: CAMEL oraz pexiganan. Najwyższą aktywnością przeciwbakteryjną odznaczał się chloroformowy ekstrakt z D. muscipula z peptydem CAMEL.
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Central and Eastern European states in global production linkages: country-level and sector-level analysis
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The exposure to UV filters: Prevalence, effects, possible molecular mechanisms of action and interactions within mixtures
PublicationSubstances that can absorb sunlight and harmful UV radiation such as organic UV filters are widely used in cosmetics and other personal care products. Since humans use a wide variety of chemicals for multiple purposes it is common for UV filters to co-occur with other substances either in human originating specimens or in the environment. There is increasing interest in understanding such co-occurrence in form of potential synergy, antagonist,...
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Ribes nigrum L. Extract-Mediated Green Synthesis and Antibacterial Action Mechanisms of Silver Nanoparticles
PublicationSilver nanoparticles (Ag NPs) represent one of the most widely employed metal-based engineered nanomaterials with a broad range of applications in different areas of science. Plant extracts (PEs) serve as green reducing and coating agents and can be exploited for the generation of Ag NPs. In this study, the phytochemical composition of ethanolic extract of black currant (Ribes nigrum) leaves was determined. The main components...
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Mangiferin Affects Melanin Synthesis by an Influence on Tyrosinase: Inhibition, Mechanism of Action and Molecular Docking Studies
PublicationMangiferin is a strong antioxidant that presents a wide range of biological activities. The aim of this study was to evaluate, for the first time, the influence of mangiferin on tyrosinase, an enzyme responsible for melanin synthesis and the unwanted browning process of food. The research included both the kinetics and molecular interactions between tyrosinase and mangiferin. The research proved that mangiferin inhibits tyrosinase...
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The Effect of Online Reviews on Consumer-Based Brand Equity: Case-Study of the Polish Restaurant Sector
PublicationPurpose: This paper focuses on the effects of positive and negative online reviews (eWOM) on the metrics of consumer-based brand equity (CBBE) in the context of the Polish restaurant sector. Methodology: The dedicated online survey was completed by 777 consumers, which we then analyzed with structural equation modeling. Each catering outlet was to allow to order meals online. We used descriptive analysis, confirmatory factor analysis,...
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Determinants of COVID-19 Impact on the Private Sector: A Multi-Country Analysis Based on Survey Data
PublicationOur paper aims to investigate the impact of COVID‐19 on private sector companies in terms of sales, production, finance and employment. We check whether the country and industry in which companies operate, government financial support and loan access matter to the behaviour and performances of companies during the pandemic. We use a microdata set from a worldwide survey of more than 15,729 companies conducted between April and...
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NON-STATIONARY THERMAL SELF-ACTION OF ACOUSTIC BEAMS CONTAINING SHOCK FRONTS IN THERMOCONDUCTING FLUID
PublicationNon-stationary thermal self-action of a periodic or impulse acoustic beam containing shock fronts in a thermoconducting Newtonian fluid is studied. Self-focusing of a saw-tooth periodic and impulse sound is considered, as well as that of a solitary shock wave which propagates with the linear sound speed. The governing equations of the beam radius are derived. Numerical simulations reveal that the thermal conductivity weakens the...
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The Palais–Smale condition for the Hamiltonian action on a mixed regularity space of loops in cotangent bundles and applications
PublicationWe show that the Hamiltonian action satisfies the Palais-Smale condition over a “mixed regular- ity” space of loops in cotangent bundles, namely the space of loops with regularity H^s, s ∈ (1/2, 1), in the baseand H^{1−s} in the fiber direction. As an application, we give a simplified proof of a theorem of Hofer-Viterbo on the existence of closed characteristic leaves for certain contact type hypersufaces in cotangent bundles.
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Study of the selection mechanism of heavy metal (Pb 2+, Cu 2+, Ni 2+ and Cd2+) adsorption on clinoptilite
PublicationBadano proces adsorpcji jonów metali ciężkich (w warunkach statycznych) z wodnych roztworów jednoskładnikowych i wieloskładnikowych na klinoptylolicie zarówno surowym jak i po wstępnej obróbce. Proces sorpcji ma charakter procesu jonowymiennego i składa sie z trzech etapów:- adsorpcji na powierzchni mikokryształów,- inwersji,- adsorpcji wewnątrz mikrokryształów.Proces sorpcji może być dobrze opisany zarówno za pomocą modelu Frendlicha...
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Night shifts as a learning experience among nursing students across Europe: Findings from a cross-sectional survey
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<title>Selection of GRNN network parameters for the needs of state vector estimation of maneuvering target in ARPA devices</title>
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Optimal Selection of Input Features and an Acompanying Neural Network Structure for the Classification Purposes - Skin Lesions Case Study
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Reaction of methanol ligated manganese(II) silanethiolate with pyridine related ligands - different structures of complexes with MnNO2S2 kernel
PublicationReakcja silanotiolanu manganu(II) z pirydyną i jej metylowymi pochodnymi prowadzi do uzyskania heteroleptycznych kompleksów o tym samym rdzeniu MnNO2S2, ale o różnym typie strukturalnym. W przypadku posłużenia się pirydyną i 2-metylopirydyną uzyskano układy zawierające dwie cząsteczki alkoholu przykoordynowane do centrum metalicznego. Z kolei w przypadku 3- i 4-metylopirydyny funkcję S,O-donorów spełniają reszty silanotiolanowe.
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Reaction of bis[bis(tri-tert-butoxysilanethiolato)cadmium(II)] with 3,5-dimethylpyridine - 113Cd NMR Solution study
PublicationAnaliza 113Cd NMR dla reakcji bis[bis(tri-tert-butoksysilanotiolanu)kadmu(II)] z 3,5-dimetylopirydyną została przeprowadzona w roztworze benzenu-d6 i toluenu-d8. Otrzymane wyniki wskazują, że w roztworze istnieje równowaga pomiędzy powstającymi mieszanymi kompleksami kadmu z ligandami siarkowymi i azotowymi.
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Social Support Mediates the Association between Health Anxiety and Quality of Life: Findings from a Cross-Sectional Study
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Long-term effects of device-guided slow breathing in stable heart failure patients with reduced ejection fraction
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The Studies on α-Pinene Oxidation over the TS-1. The Influence of the Temperature, Reaction Time, Titanium and Catalyst Content
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Advantages of continuous Fenton reaction over the traditional batch process in wastewater treatment in a single and two-step mode
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Service time distribution influence on end-to-end call setup delay calculation in networks with Session Initiation Protocol
PublicationThe most important GoS parameter for networks with SIP protocol is end-to-end call setup delay. So far there were no coherent models allowing calculation of these parameters for networks with SIP protocol. Few models were developed but they are insufficient. In the paper we propose model which allows end-to-end call setup delay calculation for networks with SIP protocol. The model is using chain of M/G/1/K models and is applicable...
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Type II secretory pathway for surface secretion of DraD invasin from the uropathogenic Escherichia coli Dr+ strain
PublicationWłaściwości wirulentne uropatogennych szczepów Escherichia coli Dr+ IH11128 związane są z obecnością struktur fimbrialnych typu Dr i białka inwazyny DraD, które może na powierzchni komórki bakteryjnej pełnić rolę fimbrialnej podjednostki szczytowej. Ostatnie badania wykazały, że białko DraD jest eksponowane na powierzchni bakterii w dwóch formach: związanej ze strukturą fimbrialną i jako niezależna od fimbrii otoczka białkowa....
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Analysis of volatile fraction of hybrid fruit pulp using Proton Transfer Reaction - Time-Of-Flight Mass Spectrometry
PublicationFruits and vegetables are important ingredients in human diet. Because of this, it is very important to know their exact composition and to control their quality. Based on the aroma of food products, it is possible to pre-evaluate their quality and freshness. The aim of this work was to characterize the volatile fraction of the hybrid fruit ‘sweetie’ using the modern analytical device PTR-TOFMS. Hybrid fruit samples are human-made...
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Reaction Model Taking into Account the Catalyst Morphology and Its Active Specific Surface in the Process of Catalytic Ammonia Decomposition
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Comparison of pathological staging and grading of urothelial bladder carcinoma in post-transurethral resection and post-radical cystectomy specimens
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Trustworthiness and Subversion in Large Service- Oriented Multi-Agent Systems under Virtual Anonymity and Blind Provider Selection
PublicationTo promote honest service provision in multi-agent systems, a Computational Trustworthiness and Rating scheme collects service ratings and computes agents' trustworthiness levels (TLs). Studies of existing schemes fail to reflect closed-loop dynamics of TLs arising from the mutual influence of agents' behavior and TLs, and to capture relevant properties. Recent simulative and analytical models produce results tied to a particular...
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Modification of TiO2 nanotubes by graphene–strontium and cobalt molybdate perovskite for efficient hydrogen evolution reaction in acidic medium
PublicationHerein, we demonstrate that modification of TiO2 nanotubes with graphene–strontium and cobalt molybdate perovskite can turn them into active electrocatalysts for hydrogen evolution reaction (HER). For this purpose, a simple method of hydrothermal synthesis of perovskites was developed directly on the TiO2 nanotubes substrate. Moreover, the obtained hybrids were also decorated with graphene oxide (GO) during one-step hydrothermal...
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The impedance of hydrogen oxidation reaction in a proton exchange membrane fuel cell in the presence of carbon monoxide in hydrogen stream
PublicationEvaluation of performance of a proton exchange membrane fuel cell, which is affected by carbon monoxide that pollutes the hydrogen stream, was presented. This influence was studied for carbon monoxide concentration of 125–325 ppb, which are close to values specified in ISO 14687:2019 standard. Performed studies provided crucial information for further development of fuel cell as an energy source for automotive application. Impedance...
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Shear Cap Size Selection Method Based on Parametric Analysis of ACI-318 Code and Eurocode 2 Standard
PublicationThe scope of the paper is to propose a method for determining the size of shear caps in a slab–column-connections-reinforced concrete structure. Usually, shear heads are used to enhance slab–column connection, especially when the transverse reinforcement does not give the required punching shear load capacity. The dimensions of the shear head should provide the punching shear resistance of the connection inside and outside the...
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Free-standing TiO2 nanotubes decorated with spherical nickel nanoparticles as a cost-efficient electrocatalyst for oxygen evolution reaction
PublicationHere, we report significant activity towards the oxygen evolution reaction (OER) of spherical nickel nanoparticles (NPs) electrodeposited onto free-standing TiO2 nanotubes (TNT) via cyclic voltammetry. It has been shown that simple manipulation of processing parameters, including scan rate and number of cycles, allows for formation of the NPs in various diameters and amounts. The polarization data with respect to transmission electron...
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A subdomain model for armature reaction field and open‐circuit field prediction in consequent pole permanent magnet machines
PublicationIn this paper, the machine quantity, such as electromagnetic torque, self and mutual inductances, and electromotive force, is analytically calculated for non-overlapping winding consequent pole slotted machine for open-circuit field and armature reaction. The sub-domain approach of (2-D) analytical model is developed using Maxwell's equations and divide the problem into slots, slot-openings, airgap and magnets region, the magnet...
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Pareto Ranking Bisection Algorithm for EM-Driven Multi-Objective Design of Antennas in Highly-Dimensional Parameter Spaces
PublicationA deterministic technique for fast surrogate-assisted multi-objective design optimization of antennas in highly-dimensional parameters spaces has been discussed. In this two-stage approach, the initial approximation of the Pareto set representing the best compromise between conflicting objectives is obtained using a bisection algorithm which finds new Pareto-optimal designs by dividing the line segments interconnecting previously...