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An in situ derivatization – dispersive liquid–liquid microextraction combined with gas-chromatography – mass spectrometry for determining biogenic amines in home-made fermented alcoholic drinks
PublicationA novel dispersive liquid–liquid microextraction (DLLME) gas chromatography mass-spectrometry(GC–MS) method was developed for the determination of 13 biogenic amines in home-made wine sam-ples. The method allows to simultaneous extraction and derivatization of the amines providing a simpleand fast mode of extract enrichment. During the study, two different procedures were examined. Sta-tistical analysis was performed to choose...
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MSRL and the Real-Life Processes of Capturing and Implementing the "Urban Innovation"
PublicationResult of the MSRL workshop, five research projects, reflect on a broader process of exchange of the ideas between the cities, that is occurring in the real life and became one of the driving factors of the urban development nowadays. The objective of the MSRL research - concepts, which help to advance the development of the cities, support the improvement of the quality of urban environment or meet the future challenges, can be...
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The influence of plant protection by effective microorganisms on the content of bioactive phytochemicals in apples
PublicationThe phytochemicals of two apple cultivars (Yellow Transparent and Early Geneva) protected in two ways, conventionally with chemical pesticides or by effective microorganisms (EM), were compared. Two types of components were determined: lipids synthesised constitutively and generated via inducible pathways polyphenols along with antioxidant activity and profiles. The antioxidant activities assessed with ABTS, DPPH and Folin–Ciocalteu...
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Collaborative Delivery by Energy-Sharing Low-Power Mobile Robots
PublicationWe study two variants of delivery problems for mobile robots sharing energy. Each mobile robot can store at any given moment at most two units of energy, and whenever two robots are at the same location, they can transfer energy between each other, respecting the maximum capacity. The robots operate in a simple graph and initially each robot has two units of energy. A single edge traversal by an robot reduces its energy by one...
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Quiet Quitting and its Link With Knowledge Risks in Organizations – Theoretical Insights
PublicationPurpose: Quiet quitting has become a widely publicized concept, driven by social media in the United States and other countries in 2022. It is a term used to describe the phenomenon by which employees do the least amount of their work, just enough to meet the requirements of one’s job description (Mahand and Caldwell, 2023). The trend is spreading quickly among young workers. It can potentially harm individuals, job performance,...
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A multiparameter simulation-driven analysis of ship turning trajectory concerning a required number of irregular wave realizations
PublicationIn times of progressive automation of the marine industry, accurate modeling of ship maneuvers is of utmost importance to all parties involved in maritime transportation. Despite the existence of modern collisionavoidance algorithms using 6DOF motion models to predict ship trajectories in waves, the impact of stochastic realization of irregular waves is usually neglected and remains under-investigated. Therefore, herein, this phenomenon...
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Overcoming Challenges of Virtual Scrum Teams: Lessons Learned Through an Action Research Study
PublicationAfter the COVID-19 breakout, agile teams found themselves in situations that “pure agilists” and textbooks on agile methods had preferred to ignore. Whereas agile mindsets helped them to quickly shift to remote work, mere virtualization of agile practices often proved insufficient, and several challenges emerged. This paper reports on an Action Research project carried out in Lufthansa Systems Poland with the aim of (1) revisiting...
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Detection of People Swimming in Water Reservoirs with the Use of Multimodal Imaging and Machine Learning
PublicationEvery year in many countries, there are fatal unintentional drownings in different water reservoirs like swimming pools, lakes, seas, or oceans. The existing threats of this type require creating a method that could automatically supervise such places to increase the safety of bathers. This work aimed to create methods and prototype solutions for detecting people bathing in water reservoirs using a multimodal imaging system and...
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Urban scene semantic segmentation using the U-Net model
PublicationVision-based semantic segmentation of complex urban street scenes is a very important function during autonomous driving (AD), which will become an important technology in industrialized countries in the near future. Today, advanced driver assistance systems (ADAS) improve traffic safety thanks to the application of solutions that enable detecting objects, recognising road signs, segmenting the road, etc. The basis for these functionalities...
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Effects of UV light irradiation on fluctuation enhanced gas sensing by carbon nanotube networks
PublicationThe exceptionally large active surface-to-volume ratio of carbon nanotubes makes it an appealing candidate for gas sensing applications. Here, we studied the DC and low-frequency noise characteristics of a randomly oriented network of carbon nanotubes under NO2 gas atmosphere at two different wavelengths of the UV light-emitting diodes. The UV irradiation allowed to sense lower concentrations of NO2 (at least 1 ppm) compared to...
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On coertia and inertia in aspects of Natanson’s nonlinear extended thermodynamics
PublicationIn this article, the previously underrepresented contributions of Natanson to the field of thermodynamics have been presented. In order to identify a source of irreversibility at Nature, Natanson introduced the concept of Coertia, which is similar to inertia. Natanson’s Coertia is a fundamental property of space that is responsible for every irreversible phenomena in matter, as well as in the electromagnetic and gravitational fields....
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Machine-aided detection of SARS-CoV-2 from complete blood count
PublicationThe current gold standard for SARS-CoV-2 detection methods lacks the functionality to perform population screening. Complete blood count (CBC) tests are a cost-effective way to reach a wide range of people – e.g. according to the data of the Central Statistical Office of Poland from 2016, there are 3,000 blood diagnostic laboratories in Poland, and 46% of Polish people have at least one CBC test per year. In our work, we show...
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Measuring Tilt with an IMU Using the Taylor Algorithm
PublicationThis article addresses the important problem of tilt measurement and stabilization. This is particularly important in the case of drone stabilization and navigation in underwater environments, multibeam sonar mapping, aerial photogrammetry in densely urbanized areas, etc. The tilt measurement process involves the fusion of information from at least two different sensors. Inertial sensors (IMUs) are unique in this context because...
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Gold(III) complexes with chloride and cyanopyridines: Facilitated hydrolysis of nitrile ligand to amide and antibacterial activity
PublicationA range of novel simple gold(III) compounds has been synthesized in their monocrystalline form, including two previously unknown chloro-complexes of Au3+ with 2-cyanopyridine or 3-cyanopyridine, respectively. Our investigations have revealed the intricate nature of the reaction between 2-cyanopyridine and tetrachloroauric acid, yielding at least three distinct products. The main product, obtained in high yield, is a salt featuring...
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Analiza oddziaływań w kryształach związków zawierających w strukturze pierścień pirydynowy
PublicationMożliwość tworzenia się wiązań wodorowych jest kluczowym parametrem z punktu widzenia inżynierii kryształu, ponieważ wiązania wodorowe mają bezpośredni wpływ na strukturę oraz trwałość sieci krystalicznej. Głównym celem niniejszej rozprawy doktorskiej była analiza porównawcza wiązań wodorowych występujących w układach, zawierających w strukturze pierścień pirydynowy. Badane układy podzielono na: (1) układy ze związkami krzemosiarkowymi...
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Metoda TrustCritic oceny wiarygodności sklepów internetowych
PublicationW artykule przedstawiono metodę oceny wiarygodności sklepów internetowych TrustCritic. Powszechnie występujące nadużycia w handlu elektronicznym sprawiają, że zaufanie do przedsiębiorcy staje się kluczowym czynnikiem decyzji konsumentów. Przedsiębiorca narażony jest na niezgodność z prawem, utratę wizerunku i klientów. Artykuł omawia problematykę nadużyć w sferze e-biznesu oraz proponuje wielokryterialny model oceny sklepu internetowego,...
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WERYFIKACJA KONCEPCJI PRZEGUBÓW PLASTYCZNYCH PROJEKTOWANYCH NA ODZIAŁYWANIA SEJSMICZNE WIADUKTU V6 OBWODNICY ISTAMBUŁU
PublicationW pracy zawarto wyniki analiz betonowego wiaduktu V6 budowanego w ciągu obwodnicy Istambułu w Turcji realizowanego w ramach projektu Northern Marmara Highway. Przeprawę stanowią dwie niezależne nitki o skrzynkowym przekroju poprzecznym i szerokości 22,00 m. Schemat statyczny obiektu to belka dziewięcioprzęsłowa o długości całkowitej 446,86 m oparta na podporach słupowych o zmiennej sztywności (rys.1) i wysokościach zmieniających...
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THE IMPACT OF GROUND TIRE RUBBER TREATMENT ON THE THERMAL CONDUCTIVITY OF FLEXIBLE POLYURETHANE/GROUND TIRE RUBBER COMPOSITES
PublicationWaste car tires are burdensome waste, and their utilization is crucial for the natural environment. In many countries, the primary method of their recycling is energy recovery, performed by simple combustion. However, material recycling is much more effective and significantly more beneficial for the natural environment. It results in the generation of ground tire rubber, which can be used to produce polymerrubber composites. It...
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Wideband Channel Measurements for Polarised Indoor Off-Body Communications
PublicationThis paper presents the initial results of wideband channel measurements for polarised off-body communication at 5.8 GHz, in an indoor environment. Channel Impulse Response measurements were performed simultaneously for two orthogonal polarisations of the wearable antenna, and repeated for vertical and horizontal orientations of the off-body one. Four types of measurement scenarios were considered in order to investigate the influence...
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Role of methylation in electron scattering on X(CH3)4 (X= C, Si, Ge) molecules (2)
PublicationTo investigate how replacement of H atom with methyl group (CH3) – in tetrahedral compounds of carbon, silicon and germanium – affects electron scattering process, total cross sections (TCS) for electron scattering from C(CH3)4, Si(CH3)4 and Ge(CH3)4 molecules have been compared with data for CH4, SiH4 and GeH4 molecules. All examined data have been obtained with the same experimental setup. The shape of all discussed TCS energy...
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Reference-free determination of debonding length in reinforced concrete beams using guided wave propagation
PublicationThis paper presents theoretical and experimental investigations of guided wave propagation in reinforced concrete beams, with pre-existing debonding between steel rebars and concrete blocks, for the purpose of damage detection. The primary aim of these investigations was a detailed analysis of the possible applications of wave propagation in single and multiple debonding detection in reinforced concrete structures and reference-free...
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Constant vs. Variable Efficiency of Electric Drive in Train Run Simulations
PublicationTrain run simulations, which focus on various power- and energy-oriented aspects, should reflect the losses in the electric powertrain. In general, the powertrain efficiency varies with respect to load and speed. Including this relation in simulation requires knowledge about detailed drivetrain parameters, which are often unavailable. This paper verifies the possibility to approximate the drivetrain efficiency in train run simulations...
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Deep eutectic solvents based assay for extraction and determination of zinc in fish and eel samples using FAAS
PublicationA new assay based on effective (high recovery) extraction by means of deep eutectic solvents (DESs) was developed for ppb level determination of zinc in fishes and eel samples. Choline chloride and Phenol in a 1:2 M ratio was selected as optimal DES-based extraction solvent. 8-Hydroxy quinoline was used as a chelating agent for zinc ions. The optimized conditions were found at pH value of 8, ligand concentration of 10 mg/L, THF...
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On the acoustic backscattering by Baltic herring and sprat
PublicationAccurate abundance estimate of Baltic clupeids, herring and sprat, is required for theirsustainable exploitation. The understanding the sound backscattering of individual fish isimportant for employing the acoustical techniques, which are widely used in the estimation.The previous studies demonstrated that the improvement of the understanding is critical forthe Baltic herring and sprat. It was the main...
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Restricted open shop scheduling
PublicationIn the real applications the open shop scheduling models often require some additional constraints and adequate models. We concern the restrictions in the open shop scheduling related to an instance of the problem and to a feasible solution. Precisely, we require that each jobs consists of the bounded number of operations and each machine has a bounded load (i.e., the total number of operations executed on this machine in a schedule)....
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Landfill leachate treatment at a pilot plant using hydrophyte systems
PublicationConstructed wetlands can provide an effective and economical solution to landfill leachate treatment. In the article the performance of a CW for leachate treatment, consisting of two horizontal flow constructed wetlands (HF-CW) beds, working at the municipal landfill in Gdansk-Szadolki in the period 2004-2005 is being discussed. The plant has been operating since 2001. Clogging problems and surface flow occurred in the system...
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Status and trends of mercury pollution of the atmosphere and terrestrial ecosystems in Poland
PublicationThe goal of this paper is to assess the current status and trends of total mercury (THg) contamination of the atmosphere and terrestrial ecosystems in Poland. The study shows that the reduced domestic and worldwide atmospheric emission of Hg resulted in decreased THg level in the terrestrial biotope and biosphere. Considering that Poland is one of the main Hg emitters in Europe, the THg concentrations in its abiotic environment...
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Effects of social media communication on brand equity and brand purchase intention
PublicationThe author studied the effect of two different social media communication on brand equity and brand purchase intention. A total of 504 data sets were generated through a standardized online-survey and analysed with structural equation modeling. The results of the empirical study showed that both firm-created and user-generated social media communication influenced brand equity, consequently impacting brand purchase intention. This...
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Influence of Wastewater Treatment Technology on Particle Size Distribution in the Effluent
PublicationSuspended solids in water and wastewater usually carry quite a large load of pollutants (organic substances, nutrients, heavy metals, etc.) adsorbed on the particles surface. Particles of different sizes carry different types and quantities of pollutants. Therefore, particle size distribution is of importance in waster and wastewater treatment. In the article the influence of different treatment technologies on particle size distribution...
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Analytical Expression for the Time-Domain Discrete Green's Function of a Plane Wave Propagating in the 2-D FDTD Grid
PublicationIn this letter, a new closed-form expression for the time-domain discrete Green's function (DGF) of a plane wave propagating in the 2-D finite-difference time-domain (FDTD) grid is derived. For the sake of its verification, the time-domain implementation of the analytic field propagator (AFP) technique was developed for the plane wave injection in 2-D total-field/scattered-field (TFSF) FDTD simulations. Such an implementation of...
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Operational problems of constructed wetland for landfill leachates treatment: case study
PublicationIn the paper the quality fluctuations of leachate from municipal landfill in Gdansk (Poland) over the last 5 years and evaluation of a wetland system designed for treatment of the leachate are discussed.The research has been conducted during the 5 years period. The constructed wetland for leachate treatment, consisting of 2 horizontal subsurface flow reed beds, working in parallel was built in 2001. In the period 2005-06 it underwent...
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Geometrical versus analytical approach in problem solving- an exploatory study
PublicationAbstract. In this study we analyse the geometrical visualization as a part of the process of solution. In total 263 students in the first year of study at three different universities in three different countries (Poland, Slovakia and Spain) were asked to solve four mathematical problems. The analysis of the results of all students showed that geometrical visualization for problems where there is a possibility to choose different ways...
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Measures of region failure survivability for wireless mesh networks
PublicationWireless mesh networks (WMNs) are considered as a promising alternative to wired local, or metropolitan area networks. However, owing to their exposure to various disruptive events, including natural disasters, or human threats, many WMN network elements located close to the failure epicentre are frequently in danger of a simultaneous failure, referred to as a region failure. Therefore, network survivability, being the ability...
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Znaczenie płci w procesie zakupu marek własnych sieci handlowych – analiza wielogrupowa
PublicationThe purpose of the article is to analyze the differences in the behavior of men and women in the process of purchasing store brands (SBs). Using an established conceptual model, we intended to identify differences, depending on gender of buyers, in the size of the effects of store image and brand price-image on perceived risk and subsequently on store brand purchase intention. A total of 652 respondents participated in the study....
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Index filtrations and Morse decomposition for discrete dynamical systems
PublicationOn a Morse decomposition of an isolated invariant set of a homeomorphism(discrete dynamical system) there are partial orderings defined by the homeomorphism.These are called admissible orderings of the...
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Extended non-linear relations of elastic shells undergoing phase transitions
PublicationThe non-linear theory of elastic shells undergoing phase transitions was proposed by two first authors in J. Elast. 79, 67-86 (2004). In the present paper the theory is extended by taking into account also the elastic strain energy density of the curvilinear phase interface as well as the resultant forces and couples acting along the interface surface curve itself. All shell relations are found from the variational principle of...
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Management of low-temperature heat source by ORC aided by additional heat source
PublicationIn the paper presented is a concept to utilize waste heat from the power plant with the aid of the low-temperature ORC cycle. The ORC system is heated from two heat sources, the first one being the flow rate of waste heat obtained from the exhaust gases. Subsequently, the working fluid in the cycle is additionally heated by the condensing steam from the low pressure turbine extraction points increasing in such way the level of...
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Determination of terpene profiles in potential superfruits
PublicationThe aim of this work was to characterize and compare the profiles of volatile terpenes in four potential superfruits. These profiles were determined using headspace solid-phase microextraction coupled with comprehensive two-dimensional gas chromatography linked to time-of-flight mass spectrometry. The proposed technique allowed the separation and identification of 79 terpenes present in cape gooseberry, crabapple, cherry silver...
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Local buckling of thin-walled channel member flange made of aluminum alloy
PublicationThe paper deals with local stability of the thin-walled compressed flange of channel columns and beams made of aluminum alloy. The aim of paper is to find critical stress of local buckling of the flange member taking into account the web-flange interaction in linear and nonlinear elastic range of the member material. The governing differential equation of the problem is derived with aid of the principle of stationary total potential...
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Evaluation of adhesive forces and the specific surface energy of zirconia stabilized by yttria with alumina additions ceramic by AFM method
PublicationThe adhesive forces and the specific surface energy of ceramic material surfaces are very important for further tribological and biomedical applications of ceramics. Partially stabilized zirconia (zirconium oxide) is popular for manufacturing various medical products. ZrO2 stabilized by Y2O3 with additions of 5 wt% alumina was produced by slip casting method with a subsequent sintering. Structure and chemical composition of ceramic...
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Characterization of metabolites in different kiwifruit varieties by NMR and fluorescence spectroscopy
PublicationIt is known from our previous studies that kiwifruits, which are used in common human diet, have preventive properties of coronary artery disease. This study describes a combination of 1H NMR spectroscopy, multivariate data analyses and fluorescence measurements in differentiating of some kiwifruit varieties, their quenching and antioxidant properties. A total of 41 metabolites were identified by comparing with literature data...
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Contamination of water in Oliwski Stream after the flood in 2016
PublicationIn the article pollution of stream waters with surface runoff from an urbanized area caused by an extremely high rainfall is discussed. The analyzes were carried out after the rainfall of the depth 152 mm which took place in Gdańsk on 14th and 15th July 2016. This extreme rainfall caused urban flooding, damage of several retention ponds and pollution of surface waters. In the article the results of physical and chemical analyzes...
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Analytical Expression for the Time-Domain Green's Function of a Discrete Plane Wave Propagating in the 3-D FDTD Grid
PublicationIn this paper, a closed-form expression for the time-domain dyadic Green’s function of a discrete plane wave (DPW) propagating in a 3-D finite-difference time-domain (FDTD) grid is derived. In order to verify our findings, the time-domain implementation of the DPW-injection technique is developed with the use of the derived expression for 3-D total-field/scattered-field (TFSF) FDTD simulations. This implementation requires computations...
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Carnivorous plants used for green synthesis of silver nanoparticles with broad-spectrum antimicrobial activity
PublicationIn this study, we exploit the anti-oxidative potential of four carnivorous plants to produce uniform and biologically active silver nanoparticles. The use of polyvinylpyrrolidone promoted syn-thesis of quasi-spherical nanoparticles characterized by stability and high uniformity. Their activity was tested against three human pathogens and three species of plant pathogenic bacteria. The study demonstrates the influence of synthesis...
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Praseodymium Orthoniobate and Praseodymium Substituted Lanthanum Orthoniobate: Electrical and Structural Properties
PublicationIn this paper, the structural properties and the electrical conductivity of La1−xPrxNbO4+δ (x = 0.00, 0.05, 0.1, 0.15, 0.2, 0.3) and PrNbO4+δ are presented and discussed. All synthesized samples crystallized in a monoclinic structure with similar thermal expansion coefficients. The phase transition temperature between the monoclinic and tetragonal structure increases with increasing praseodymium content from 500 ◦C for undoped...
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The role of low-energy electrons in the charging process of LISA test masses
PublicationThe estimate of the total electron yield is fundamental for our understanding of the test-mass charging associated with cosmic rays in the Laser Interferometer Space Antenna (LISA) Pathfinder mission and in the forthcoming gravitational wave observatory LISA. To unveil the role of low energy electrons in this process owing to galactic and solar energetic particle events, in this work we study the interaction of keV and sub-keV...
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Exploring the Prevalence of Anti-patterns in the Application of Scrum in Software Development Organizations
PublicationThe paper presents a survey-based study that aimed to determine the prevalence of anti-patterns in the Scrum software development methodology. A total of 35 anti-patterns were selected from the literature review, and 42 respondents indicated whether they had encountered each anti-pattern in their organizations. The study found that``Unfinished Tasks'' was the most prevalent anti-pattern, highlighting the importance of proper planning...
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Properties of Barium Cerate-Zirconate Thin Films
PublicationIn this work, we review several experimental results showing the electrical properties of barium cerate-zirconate thin films and discuss them in view of the possible influence of various factors on their properties. Most of the presented Ba(Ce, Zr, Y)O3 thin films were formed by the pulsed laser deposition (PLD) technique, however thin films prepared using other methods, like RF magnetron sputtering, electron-beam deposition, powder...
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Occurrence and Levels of Biogenic Amines in Beers Produced by Different Methods
PublicationThe concentration of biogenic amines (BAs) in beer depends, among other factors, on the activity of microorganisms, in particular lactic acid bacteria. In this work an analytical method based on derivatization with tosyl chloride and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was used to determine 17 BAs in samples of commercially available beers, and to monitor the changes in concentration of...
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AGREEprep – Analytical greenness metric for sample preparation
PublicationThis work proposes for the first time, a metric tool that gives prominence to sample preparation. The developed metric (termed AGREEprep) was based on 10 categories of impact that were recalculated to 0 e1 scale sub-scores, and then used to calculate the final assessment score. The criteria of assessment evaluated, among others, the choice and use of solvents, materials and reagents, waste generation, energy consumption, sample...