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Tailoring a low-energy ball milled MnCo2O4 spinel catalyst to boost oxygen evolution reaction performance
PublikacjaThe development of cost-efficient oxygen evolution reaction (OER) catalysts is one of the most important tasks facing modern techniques for hydrogen production. In this work, for the first time, a low-energy ball milling process of MnCo2O4 (MCO) spinel powders, with a mechanical modification time exceeding 1 day was used. After 6 days of ball-milling, the obtained overpotential of the electrocatalyst reached the value of 375 mV...
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Short-term Price Reaction to Involuntary Bankruptcies Filed in Bad Faith: Empirical Evidence from Poland
PublikacjaPurpose: Assessing the reaction of the prices of shares of companies listed in the Warsaw Stock Exchange to the public disclosure of information about the filing a bankruptcy petition in bad faith by creditors. Design/Methodology/Approach: Event study analysis. Findings: It can therefore be assumed that the filing of an unfounded bankruptcy petition does not, in the short term, have a statistically significant negative impact on...
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Convenient Synthesis of Functionalized Unsymmetrical Vinyl Disulfides and Their Inverse Electron-Demand Hetero-Diels-Alder Reaction
PublikacjaThe 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
PublikacjaWith 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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First evaluation of wastewater discharge influence on marine water contamination in the vicinity of Arctowski Station (Maritime Antarctica)
PublikacjaIn 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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Glutathione-mediated conjugation of anticancer drugs: an overview of reaction mechanisms and biological significance for drug detoxification and bioactivation.
PublikacjaThe 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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Application of hydroacoustic system of distance measurement for estimating the cod codends shape at the model research station in Insko
PublikacjaPraca przedstawia wyniki pomiarów kształtu worków dorszowych w stacji badań modelowych Politechniki Szczecińskiej w Ińsku. Badane worki dorszowe są workamispecjalnie zaprojektowanymi do połowów selektywnych. W celu precyzyjnego pomiaru parametrów geometrycznych worków został opracowany nowy hydroakustyczny system do precyzyjnych pomiarów odległości. Zapewnia on równoczesny pomiar maksymalnie 100 różnych wymiarów w zakresie od 0.1m...
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Persistent organic pollutants (POPs) as an indicator of surface water quality in the vicinity of the Polish Polar Station, Horsund
PublikacjaSurface 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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The influence of a change in the meniscus cross-sectional shape on the medio-lateral translation of the knee joint and meniscal extrusion
PublikacjaObjective The purpose of this study was to evaluate the influence of a change in the meniscus cross sectional shape on its position and on the biomechanics of a knee joint. Methods One main finite element model of a left knee joint was created on the basis of MRI images. The model consisted of bones, articular cartilages, menisci and ligaments. Eight variants of this model with an increased or decreased meniscus height were then...
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Laboratory station for research of the innovative dry method of exhaust gas desulfurization for an engine powered with residual fuel
PublikacjaContemporary 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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A decision-making system supporting selection of commanded outputs for a ship's propulsion system with a controllable pitch propeller
PublikacjaThe 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
PublikacjaWe 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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GNSS reference solution for permanent station stability monitoring and geodynamical investigations: the ASG-EUPOS case study.
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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
PublikacjaNovel 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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Real-Time Monnitoring of Vegetable Oils' Thermal Degradation Using Proton Transfer Reaction Mass Spectrometry
PublikacjaThe volatile aldehydes, which are generated during frying, can be harmful to human health, therefore the concentration of these compounds in frying fumes should be monitored. In addition, aldehydes are markers of oils’ quality, and so it is possible to determine shelf-life or suitability for frying of these oils. Commonly, in order to determine aldehydes concentration gas chromatography is performed, however it does not allow for...
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Manual work in cold environments and its impact on selection of materials for protective gloves based on workplace observations
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Investigations of local/global buckling of cylindrical metal silos with corrugated sheets and open-sectional column profiles
PublikacjaArtykuł 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)
PublikacjaPolystachya 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
PublikacjaIn 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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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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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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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
PublikacjaMorpholinium-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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Solvation of ionic liquids based on N-alkyl-N-methylmorpholinium cations in N,N-dimethylformamide and dimethyl sulfoxide – A volumetric and acoustic study
PublikacjaApparent 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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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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Mangiferin Affects Melanin Synthesis by an Influence on Tyrosinase: Inhibition, Mechanism of Action and Molecular Docking Studies
PublikacjaMangiferin 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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Central and Eastern European states in global production linkages: country-level and sector-level analysis
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Polymer-free cubosomes for simultaneous bioimaging and photodynamic action of photosensitizers in melanoma skin cancer cells
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Selected symmetrically substituted carbazoles: Investigation of anticancer activity and mechanisms of action at the cellular and molecular levels
PublikacjaDNA topoisomerases play a critical role as essential enzymes in controlling alterations in the topology of DNA. They achieve this by orchestrating the coordinated process of breaking and rejoining DNA strands, which is crucial for maintaining the proper structure of DNA during regular cellular development. The search for and development of new potential anticancer drugs is a challenging yet immensely important area of research...
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The Palais–Smale condition for the Hamiltonian action on a mixed regularity space of loops in cotangent bundles and applications
PublikacjaWe 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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The exposure to UV filters: Prevalence, effects, possible molecular mechanisms of action and interactions within mixtures
PublikacjaSubstances 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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Synergistic action of extracts from carnivorous plants and synthetic peptides against plant pathoghenic bacteria
Publikacjaw 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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Ribes nigrum L. Extract-Mediated Green Synthesis and Antibacterial Action Mechanisms of Silver Nanoparticles
PublikacjaSilver 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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Determinants of COVID-19 Impact on the Private Sector: A Multi-Country Analysis Based on Survey Data
PublikacjaOur 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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The Effect of Online Reviews on Consumer-Based Brand Equity: Case-Study of the Polish Restaurant Sector
PublikacjaPurpose: 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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NON-STATIONARY THERMAL SELF-ACTION OF ACOUSTIC BEAMS CONTAINING SHOCK FRONTS IN THERMOCONDUCTING FLUID
PublikacjaNon-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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Study of the selection mechanism of heavy metal (Pb 2+, Cu 2+, Ni 2+ and Cd2+) adsorption on clinoptilite
PublikacjaBadano 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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Type II secretory pathway for surface secretion of DraD invasin from the uropathogenic Escherichia coli Dr+ strain
PublikacjaWłaściwości 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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<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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Night shifts as a learning experience among nursing students across Europe: Findings from a cross-sectional survey
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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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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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Reaction of bis[bis(tri-tert-butoxysilanethiolato)cadmium(II)] with 3,5-dimethylpyridine - 113Cd NMR Solution study
PublikacjaAnaliza 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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Service time distribution influence on end-to-end call setup delay calculation in networks with Session Initiation Protocol
PublikacjaThe 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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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
PublikacjaTo 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...