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  • Time-Gating method with automatic calibration for accurate measurements of electrically small antenna radiation patterns in Non-Anechoic environments
    • Adrian Bekasiewicz
    • Sławomir Kozieł
    • Michał Czyż
    2023 Pełny tekst MEASUREMENT

    Non-anechoic sites represent a cheap alternative to measurements of antennas in dedicated facilities. However, due to a high noise—from the external EM signal sources and multipath interferences—the quality of radiation patterns obtained in non-anechoic conditions is poor. The characteristics can be corrected using a time-gating method (TGM), which involves filtering of the noise based on temporal analysis of the measured signals. Unfortunately, determination of appropriate TGM setup is prone to failure due to its manual, or semi-manual nature. In this work, an automatic TGM calibration algorithm for accurate measurements in non-anechoic environments has been proposed. The method involves calibration of the test site using the antenna with known accurate responses. The process is implemented as an optimization routine where TGM intervals are adjusted through a curve fitting of the on-site measurements to the reference radiation patterns. The proposed framework has been demonstrated using four compact radiators and validated against the state-of-the-art techniques. Applicability of the method for calibration of the measurements in distinct test sites, as well as the analysis of the aliasing and external noise on the quality of corrected measurements have also been investigated.

  • TIME-OF-FLIGHT DIFFERENTIAL ELECTRON SCATTERING FROM MOLECULAR TARGETS: BENCHMARK CROSS SECTIONS
    • Mateusz Zawadzki
    • Murtadha Khakoo
    2023

    We report time-of-flight differential cross section (DCS) measurements for the electron impact excitation transition in H2. In this work, agreement between available theory and experiment is excellent overall, and marks a transition in electron molecule scattering where differential scattering of excitation is found to be in such precise agreement. We also prove that the newly built apparatus can be used for accurate measurement of the mass stopping power for low energy electrons for H2 for which agreement between theory and experiment is found to be excellent.

  • TiO2-C nanocomposite synthesized via facile surfactant-assisted method as a part of less energy-consuming LED-based photocatalytic system for environmental applications
    • Adam Kubiak
    • Anna Grzegórska
    • Elżbieta Gabała
    • Joanna Zembrzuska
    • Mirosław Szybowicz
    • Hubert Fuks
    • Anna Szymczyk
    • Anna Zielińska-Jurek
    • Marek Sikorski
    • Teofil Jesionowski
    2023 Pełny tekst JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY

    A novel facile method was used to incorporate carbon into the titania structure. An alternative synthesis method of carbon-doped TiO2 has been proposed by using a widely used and cheap surfactant. During the process, cetyltrimethylammonium bromide plays a dual role, as a morphology modifier and as a carbon source. The presented approach allows obtained TiO2-C nanostructures to be anatase nanocrystals with carbon being deposited either on the surface or between the TiO2 nanoparticles. The innovative nature of the research subject is related to the design of cheap LED solutions and facile synthesis of TiO2-C for use in novel energy-saving photocatalytic systems. Photocatalytic studies showed promising activity in the oxidation of 4-chlorophenol. Furthermore, it was indicated that LED-based photocatalytic systems allow a significant reduction in energy consumption compared to conventional photocatalytic sets. In addition, the high thermal efficiency of LED systems was confirmed with a thermal imaging camera. Hence, the presented novel LED photocatalytic systems can be an important part of a broad strategy for the protection of the environment.

  • Topography measurement methods evaluation for entire bending-fatigued fracture surfaces of specimens obtained by explosive welding
    • Przemysław Podulka
    • Wojciech Macek
    • Dariusz Rozumek
    • Krzysztof Żak
    • Ricardo Branco
    2023 Pełny tekst MEASUREMENT

    In this paper, the methods of compensation of differences in the results of entire bending-fatigued fracture surface topographies were presented. The roughness evaluation was performed with a focus variation microscope and confocal surface topography measurement techniques. The differences in the ISO 25178 roughness parameters were investigated and procedures for their compensation were studied. It was found that various types of optical measurements can cause differences in the errors occurring in the measurement process, such as outliers, and noise. The reduction of differences in the various optical roughness measurements can be attained when measurement errors are compensated. For this study, the applications of general procedures available in commercial software can be suitable for improvements of the roughness measurement results, such as raw data thresholding technique, digital filtering (S-filter), power spectral density, and autocorrelation function analyses. The validation of measurement techniques was proposed for areal and profile studies, including analysis of differences in the calculation areal ISO 25178 roughness parameters.

  • Topological-numerical analysis of a two-dimensional discrete neuron model
    • Paweł Pilarczyk
    • Justyna Signerska-Rynkowska
    • Grzegorz Graff
    2023 Pełny tekst CHAOS

    We conduct computer-assisted analysis of a two-dimensional model of a neuron introduced by Chialvo in 1995 [Chaos, Solitons Fractals 5, 461–479]. We apply the method of rigorous analysis of global dynamics based on a set-oriented topological approach, introduced by Arai et al. in 2009 [SIAM J. Appl. Dyn. Syst. 8, 757–789] and improved and expanded afterward. Additionally, we introduce a new algorithm to analyze the return times inside a chain recurrent set. Based on this analysis, together with the information on the size of the chain recurrent set, we develop a new method that allows one to determine subsets of parameters for which chaotic dynamics may appear. This approach can be applied to a variety of dynamical systems, and we discuss some of its practical aspects. In the last three decades, various discrete models of a single neuron were introduced, aimed at reflecting the dynamics of neural processes. Unfortunately, analytical methods offer limited insight into the nature of some phenomena encountered by such models. In this paper, we study the classical multi-parameter Chialvo model by means of a novel topological method that uses set-oriented rigorous numerics combined with computational topology. We enrich the existing tools with a new approach that we call finite resolution recurrence. We obtain a comprehensive picture of global dynamics of the model, and we reveal its bifurcation structure. We combine the recurrence analysis with machine learning methods in order to detect parameter ranges that yield chaotic behavior.

  • Total impact of oxidative stress genes on cardiovascular events—a 7-year follow-up study
    • Milena Racis
    • Anna Stanisławska-Sachadyn
    • Wojciech Sobiczewski
    • Marcin Wirtwein
    • Michał Krzemiński
    • Andrzej Rynkiewicz
    • Bartosz Wasąg
    • Miłosz Jaguszewski
    • Marcin Gruchała
    2023 Pełny tekst JOURNAL OF APPLIED GENETICS

    Cardiovascular (CV) events are the number one cause of lifetime disability and deaths worldwide. It is well known that traditional risk factors do not fully correlate with clinical outcomes; therefore, searching for other markers that would explain CV events occurrence seems essential. Of importance, one of the main factors at the origin of CV events is oxidative stress, causing inflammation and atherosclerotic plaque instability. Therefore the present study was conducted to evaluate eight carefully selected genetic polymorphisms related to oxidative stress as risk modifiers for CV events. A cohort of 1020 patients with coronary atherosclerosis was analysed in a 7-year follow-up observational study. The following endpoints were assessed: CV death, myocardial infarction (MI) and a combined endpoint of CV death/MI/stroke. Our results show that single polymorphisms are not significant cardiovascular disease risk factors, but genetic risk score (GRS), defined as the accumulation of our eight studied polymorphisms, was significantly associated with the three. Specifically, low GRS was associated with a higher risk of CV death, MI and CV death/MI/stroke. In conclusion, when regarding CV events, GRS investigated here can become clinically meaningful and undoubtedly adds to the knowledge in stratifying the risk of CV events.

  • Toward Safe and Efficient Recovery of Gas Munitions Dumped at Sea
    • Lech Rowiński
    • Thanh Hai Truong
    • Phuoc Quy Phong Nguyen
    2023 Pełny tekst Polish Maritime Research

    The proposal of a system for the safe recovery of unexploded ordnance (UXO), chemical weapons (CW) and chemicalwarfare agents (CWA) dumped at sea mainly after WWI and WWII is described in this work. The proposed solutionaddresses the tasks required to neutralise thousands of tons of dumped material and the currently available solutionsand proposed ideas. Requirements concerning the features of a recovery system are defined and scrutinised, thesebeing intended to ensure the safety of this phase of the UXO/CW neutralisation process. To meet this requirement,the concept of a remotely operated, two-component working size underwater vehicle is proposed, supplemented bya properly sized and outfitted surface platform that is an important part of the recovery system. Finally, the basiccomponents of the proposed system configuration are characterised, together with their functions during the recoveryof dangerous CWA-related objects

  • Towards a Framework for Context Awareness Based on Textual Process Data
    • Aleksandra Revina
    • Nina Rizun
    • Aksu Ünal
    2023

    Context awareness is critical for the successful execution of processes. In the abundance of business process management (BPM) research, frameworks exclusively devoted to extracting context from textual process data are scarce. With the deluge of textual data and its increasing value for organizations, it be-comes essential to employ relevant text analytics techniques to increase the awareness of business process (BP) workers, which is important for BP execu-tion. Following the design science research guidelines, the present paper ad-dresses this demand by developing a framework for context awareness based on textual process data using a well-established layered BPM context model. This framework combines and maps various text analytics techniques to the layers of the context model, aiming to increase the context awareness of BP workers and facilitate informed decision-making. The framework is conceptualized in an IT ticket processing case study. The findings show that contextual information ob-tained using our framework enriches the awareness of BP workers regarding the process instance urgency, complexity, and upcoming tasks and assists in making decisions in terms of these aspects

  • Towards High-Value Datasets Determination for Data-Driven Development: A Systematic Literature Review
    • Anastasija Nikiforova
    • Nina Rizun
    • Magdalena Ciesielska
    • Charalampos Harris Alexopoulos
    • Andrea Miletić
    2023

    Open government data (OGD) is seen as a political and socio-economic phenomenon that promises to promote civic engagement and stimulate public sector innovations in various areas of public life. To bring the expected benefits, data must be reused and transformed into value-added products or services. This, in turn, sets another precondition for data that are expected to not only be available and comply with open data principles, but also be of value, i.e., of interest for reuse by the end-user. This refers to the notion of “high-value dataset” (HVD), recognized by the European Data Portal as a key trend in the OGD area in 2022. While there is progress in this direction, e.g., the Open Data Directive, incl. identifying 6 key categories, a list of HVDs and arrangements for their publication and re-use, they can be seen as “core” / “base” datasets aimed at increasing interoperability of public sector data with a high priority, contributing to the development of a more mature OGD initiative. Depending on the specifics of a region and country - geographical location, social, environmental, economic issues, cultural characteristics, (under)developed sectors and market specificities, more datasets can be recognized as of high value for a particular country. However, there is no standardized approach to assist chief data officers in this, and there is a clear lack of conceptualizations for the determination of HVD and systematic oversight. In this paper, we present a systematic review of existing literature on HVD determination, which is expected to form an initial knowledge base for this process, including used approaches and indicators to de-termine them, data, stakeholders

  • Towards large-scale application of nanoporous materials in membranes for separation of energy-relevant gas mixtures
    • Roberto Castro Munoz
    • Kumar V. Agrawal
    • Zhiping Lai
    • Joaquín Coronas
    2023 Pełny tekst SEPARATION AND PURIFICATION TECHNOLOGY

    Membranes containing nanoporous materials (such as zeolites, metal–organic materials and 2D materials such as graphene derivatives) may allow more efficient separation of gas mixtures relevant to emerging energy technologies. For example, such membranes could be applied in the separation of gases containing mixtures of carbon dioxide (CO2) and hydrogen (H2). However, these membranes are currently at a relatively low technology readiness level. Hence, here we review the opportunities and challenges of applying these porous materials in practice and at scale in membranes for possible commercialization. Besides, we highlight the necessity of improvements in the porosity control of 2D materials and the decrease in the selective membrane skin layer when adapted in asymmetric membranes. In this latter point, we declare the main limitations of porous supports, as well as the further developments needed in the gutter layer and supports. Additionally, we review the main membrane module configurations and process requirements, declaring the most suitable configurations (e.g. spiral wound and hollow fiber modules) at scale with promising future for highly intensified membrane modules for application in CO2 and H2 separations. Finally, apart from the conclusions derived from this review, we outline useful recommendations for the researchers in the field.

  • Towards more inclusive qualitative research: the practice of interviewing neurominorities
    • Joanna Szulc
    2023 Pełny tekst Labour & Industry-A Journal of the Social and Economic Relations of Work

    Management scholars increasingly focus their efforts on the development of neurodivergent human capital and the promotion of inclusive employment and decent work. However, it may be argued that existing research still suffers from the lack of a comprehensive appreciation of what neurominorities may find difficult in the research process or how they interpret what the researchers are doing. In the light of only fragmented advice about how qualitative research with neurominorities should be conducted, this short research note aims to promote effective and inclusive qualitative research that ensures that the specific needs of neurominorities are taken into account throughout the entire research pathway. Building on the existing literature and my own reflections, I call on qualitative management scholars to engage in research that is truly impactful at multiple levels by re-considering how they make impact on those who traditionally have less voice or power.

  • Towards Robust Identification of Nonstationary Systems
    • Artur Gańcza
    • Marta Chełkowska
    • Natalia Kleinschmidt
    2023 Pełny tekst

    The article proposes a fast, two-stage method for the identification of nonstationary systems. The method uses iterative reweighting to robustify the identification process against the outliers in the measurement noise and against the numerical errors that may occur at the first stage of identification. We also propose an adaptive algorithm to optimize the values of the hyperparameters that are crucial for this new method.

  • TQM jako podstawa przemian projakościowych w szkolnictwie wyższym
    • Piotr Grudowski
    2023 Pełny tekst Problemy Jakości

    Cel: Przedstawienie najważniejszych wniosków płynących z badań prowadzonych w różnych regionach świata oraz obserwacji własnych prezentujących wpływ koncepcji TQM na efekty zarządzania w instytucjach szkolnictwa wyższego. Projekt badania/metodyka badawcza/koncepcja: Wykorzystano studium literatury wg zaleceń metodycznych J. Creswella. Wnioski płynące z rozważań oparto, przede wszystkim, na podejściu indukcyjnym. Wyniki/wnioski: Przedstawiono czynniki wspierające wprowadzanie TQM w szkołach wyższych. Wskazano także typowe problemy spotykane w związku z wprowadzaniem TQM oraz koncepcji pokrewnych w uczelniach. Określono warunki skutecznej integracji inicjatyw projakościowych w uczelniach z koncepcją Jakości 4.0 i Społeczeństwa 5.0. Ograniczenia: Wybrano jedynie najważniejsze – zdaniem autora – czynniki wspierające i problemy dotyczące aplikacji TQM w szkołach wyższych. Wnioski ograniczają się do wyników badań dostępnych w ramach studium literatury światowej i doświadczeń własnych autora. Zastosowanie praktyczne: Wskazane wnioski z badań oraz praktycznych doświadczeń mogą być uwzględnione przez personel uczelni odpowiedzialny za doskonalenie procesów w ramach konkretnych projektów. Oryginalność/wartość poznawcza: Artykuł pełni rolę porządkującą, jeśli chodzi o teorię i praktykę dotyczące roli koncepcji TQM w doskonaleniu systemów zarządzania szkół wyższych, wskazując czynniki, które powinny być przedmiotem dociekań w tym zakresie.

  • Trade of the European Union with the Post-Soviet Republics of Central Asia in the Second Decade of the 21st Century
    • Krystyna Gomółka
    2023 Studia Wschodnioeuropejskie

    .The article presents the European Union's trade with five Central Asian countries: Kazakhstan, Turkmenistan, Tajikistan, Kigistan and Uzbekistan in the two decades of the 21st century.

  • TRAINING ON SUSTAINABLE DAYLIGHTING: THE NLITED PROJECT
    • Natalia Sokół
    • Federica Giuliani
    • M. Sarey Khanie
    • Valerio Roberto Maria Lo Verso
    • Niko Gentile,
    2023

    NLITED - New Level of Integrated Techniques for Daylighting Education is a European project bridging a daylight design education gap. The paper describes the framework of the project, which consists of a free online e-platform with 32 modules dedicated to daylight knowledge within the built environment used by almost 800 learners (students and professionals). Two 7-day summer schools support the e-platform. The e-content was created by more than 30 international tutors based on a series of workshops and online surveys to define the need for sustainable daylight training. The paper addresses a gap in the literature on daylight education by describing the functioning e-platform and its usage results.

  • Transformation of bimetallic Ag–Cu thin films into plasmonically active composite nanostructures
    • Marcin Łapiński
    • Robert Kozioł
    • Wojciech Skubida
    • Piotr Winiarz
    • Rowa Mahjoub Yahia Elhassan
    • Wojciech Sadowski
    • Barbara Kościelska
    2023 Pełny tekst Scientific Reports

    Formation of plasmonically active silver, copper and composite silver-copper nanostructures were studied in this paper. Metallic nanostructures were fabricated by thermal disintegration, so called dewetting, of the thin films in an argon atmosphere. The formation process of the nanostructures was in-situ observed by a novel method, based on resistance measurements. The influence of the material and thickness of the initial thin film on temperature of their disintegration was investigated. Electrical measurements were validated by scanning electron microscopy observations, while metallic the behavior of nanostructures was studied by XPS method. The formation of silver-copper nanocomposite structures was confirmed by UV–vis spectroscopy. Plasmon resonance with two characteristic peaks for nanocomposite structures was observed.

  • Transformator z tyrystorowym przełącznikiem zaczepów jako obiekt sterowania
    • Piotr Sępka
    • Maciej Brzycki
    • Artur Cichowski
    2023 Pełny tekst Przegląd Elektrotechniczny

    Artykuł jest wynikiem realizacji studenckiego projektu, którego obiektem badań były transformatory z tyrystorowym podobciążeniowym przełącznikiem zaczepów (PPZ), znajdujące się w Laboratorium LINTE^2. Projekt obejmował analizę stanów przejściowych zachodzących podczas przełączania tyrystorów. W referacie przedstawiono opracowany model tyrystorowego przełącznika zaczepów wraz z wynikami badań symulacyjnych.

  • Transport of dangerous goods by rail, and threats to the subsoil of the railway surface in the event of a disaster
    • Eligiusz Mieloszyk
    • Anita Milewska
    • Mariusz Wyroślak
    2023 Pełny tekst AIP Conference Proceedings

    In Poland, in 2020, the mass of dangerous goods (loads) transported by rail was 26 151.06 thousand tone. This translated into the performance of 8 899 691.89 thousand tone - km of transport performance. In 2020, these figures accounted for 11.72% of the weight of goods transported by rail. The situation is similar in other countries around the world. With such a large volume of transport of dangerous goods by rail, there is a high risk of a railway disaster involving hazardous materials. The effects of such a catastrophe affect the ground surface of the railway track and groundwater. For modeling, generalized dynamical systems are used. These are mathematical models of real systems describing the relationships between the so-called input ⃗ and output (response) of a dynamical system. In the case of the railway disasters discussed here, they determine the functions showing the way the effects of the disaster spread in the subsoil of the railway track and show the properties of these functions. For this modeling, a non-classical calculus of operators is used that generates generalized dynamical systems, as the phenomenon of spreading the effects of a catastrophe in the ground is a complex dynamic process. It can be either slow or abrupt. This has been taken into account in the process analysis. It has been shown that the occurrence of a disaster, including the one involving hazardous materials, is influenced by the reliability of the railway line and its components, as well as the reliability of the subsoil. It was indicated that the effects of a disaster involving hazardous materials affect the discussed reliability. Determining the function of unreliability, reliability and intensity of damage to the subsoil is helpful in determining the methods of restoring the subsoil to its original (initial) operating parameters.

  • TRAVELLING WAVES FOR LOW–GRADE GLIOMA GROWTH AND RESPONSE TO A CHEMOTHERAPY MODEL
    • Agnieszka Bartłomiejczyk
    • Marek Bodnar
    • Magdalena U. Bogdańska
    • Monika Piotrowska
    2023 Pełny tekst International Journal of Applied Mathematics and Computer Science

    Low-grade gliomas (LGGs) are primary brain tumours which evolve very slowly in time, but inevitably cause patient death. In this paper, we consider a PDE version of the previously proposed ODE model that describes the changes in the densities of functionally alive LGGs cells and cells that are irreversibly damaged by chemotherapy treatment. Besides the basic mathematical properties of the model, we study the possibility of the existence of travelling wave solutions in the framework of Fenichel’s invariant manifold theory. The estimates of the minimum speeds of the travelling wave solutions are provided. The obtained analytical results are illustrated by numerical simulations.

  • Trends in Locally Balanced Energy Systems without the Use of Fossil Fuels: A Review
    • Łukasz Mazur
    • Sławomir Cieślik
    • Stanisław Czapp
    2023 Pełny tekst ENERGIES

    In recent years, the idea of the operation of energy systems (power systems, heating systems) has changed significantly. This paper is an overview of locally balanced energy systems without the use of fossil fuels. The paper justifies the concept of local energy balancing in a new energy system that does not use fossil fuels (coal, natural gas, and crude oil), based on European Union guidelines and formal documents as well as the literature on the subject. In this context, the issue of local energy self-sufficiency, utilizing renewable energy sources, as well as the concept of local smart grids based on innovative market mechanisms are raised. Attention is also paid to technical issues with regard to locally balanced energy systems, in particular photovoltaic sources and energy storage. Challenges related to the use of electrical protection in networks with many sources of energy are described. In such networks, the power flow is not in one direction only. Moreover, the selection of protections is problematic due to the distribution of short-circuit currents. Additionally, earth fault currents in such networks may be distorted, and this negatively affects the operation of residual current devices. The basic nomenclature describing locally balanced systems has been sorted out as well. Finally, possible future research paths in the field of creating locally balanced systems without the use of fossil fuels are presented.

  • Triplet Formation and Triplet‐Triplet Annihilation Upconversion in Iodine Substituted Non‐Orthogonal BODIPY‐Perylene Dyads
    • Keshav Kumar Jha
    • Amrutha Prabhakaran
    • Rengel Cane Sia
    • Ruben Arturo Arellano-Reyes
    • Nirod Kumar Sarangi
    • Tingxiang Yang
    • Krishan Kumar
    • Stephan Kupfer
    • Julien Guthmuller
    • Tia E. Keyes
    • Benjamin Dietzek-Ivanšić
    2023 Pełny tekst ChemPhotoChem

    BODIPY-perylene dyads have emerged as useful metal free sensitizers for triplet-triplet annihilation upconversion (TTAUC), these dyads are capable of efficient triplet generation via spinorbit charge transfer intersystem crossing (SOCT-ISC). This important route to triplet formation requires dyads in which two moieties are oriented perpendicular to each other. In this contribution, we give a deeper insight on the behavior of recently reported BODIPY-perylene dyads, where BODIPY-perylene dihedral exhibits a non-orthogonal dyad geometry. The intersystem crossing of BODIPY-perylene dyads with and without iodine are investigated using femtosecond transient absorption (fs-TA) and nanosecond transient absorption (ns-TA) spectroscopy. The concurrent decay of the singlet charge transfer state (1CT) and rise of triplet states in both the iodinated and non-iodinated dyads confirms the SOCT-ISC as the main intersystem crossing pathway despite the altered geometry of the dyads. The presence of an iodine atom on the BODIPY-moiety enables intersystem crossing 2.6-times faster and provides a higher triplet yield with respect to dyad without iodine. The upconversion quantum yield is 8.4-times higher in the sample containing iodinated dyad as sensitizer and perylene as annihilator. The triplet-triplet energy transfer rate (kTTET) is ~8×10^8 M-1.s-1 for both iodinated and noniodinated sensitizer containing TTAUC systems in 1,4-dioxane.

  • Trójfazowy 4-gałęziowy falownik SiC w napędzie z wysokoobrotowym silnikiem indukcyjnym
    • Marek Adamowicz
    • Sebastian Giziewski
    • Zbigniew Krzemiński
    2023 Pełny tekst Przegląd Elektrotechniczny

    Zastosowanie tranzystorów SiC w falownikach napędów wysokoobrotowych powoduje nowe wyzwania,szczególnie odnośnie generowanego w falowniku napięcia common mode (CM) o wysokiej częstotliwości. Wysokoczęstotliwościowe napięcie CM wchodzi w interakcję z pojemnościami pasożytniczymi falownika, kabla i silnika wymuszając przepływ prądów CM, które są źródłem strat w filtrach pasywnych oraz powodują zakłócenia pomiarów prądów, nieakceptowalne z punktu widzenia działania przekształtnika. Ze wzrostem częstotliwości rośnie poziom emisji zaburzeń elektromagnetycznych spowodowany rezonowaniem obwodu CM, a tym samym niekorzystnie rośnie masa, gabaryt i koszt dławików CM. W referacie zaproponowano zastosowanie 4-gałęziowego falownika SiC z metodą sterowania zapewniającą eliminację napięcia CM celem poprawy właściwości napędu wysokoobrotowego.

  • Truss imperfections in the design of bar and diaphragm bracing systems
    • Natalia Korcz-Konkol
    • Piotr Iwicki
    2023 Pełny tekst JOURNAL OF CONSTRUCTIONAL STEEL RESEARCH

    In the article three variants of roof bracing were considered: bar bracing, diaphragm bracing and the combination of bar and diaphragm bracing. Different analytical and numerical ways of taking into account the imperfections of the truss girder were compared. The entire 3D model of the roof (shell and beam elements with the eccentricities taken into account) was analysed numerically. Selected stressed-skin aspects were considered. Stabilizing forces in the purlins and forces in bracing elements (bar and/or diaphragm bracing, connections) were observed. The importance of the imperfection issues (e.g. shape of the imperfection, method of including imperfection, wind forces) was evaluated numerically to indicate the key points in the design procedure. The biggest forces in purlins occurred for “nonstandard” shape of the imperfection. On the other hand, in case of bracing elements, when wind forces were taken into consideration, “standard” approach of including the imperfection was safe approximation. Moreover, the diaphragm took over significant part of the bracing forces, however the distribution of the forces depended strongly on the flexibility of the bracing and purlin/truss connection.

  • Trustworthiness and Subversion in Large Service- Oriented Multi-Agent Systems under Virtual Anonymity and Blind Provider Selection
    • Jerzy Konorski
    2023

    To 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 attack scenario, or restricted to small-size systems or simplistic agent behavior. We analyze a class of parameterized skimp and slander attacks in a challenging setting featuring agents' virtual anonymity, collusion, and blind, i.e., TL-insensitive selection of service providers, as well as unpredictable service availability and receptivity. We derive closed-loop Markovian TL dynamics and their mean-value approximation to analytically characterize agents' steady-state TLs, and find a systematic defense against skimp and slander.

  • Tuning of eg electron occupancy of MnCo2O4 spinel for oxygen evolution reaction by partial substitution of Co by Fe at octahedral sites
    • Krystian Lankauf
    • Karolina Górnicka
    • Patryk Błaszczak
    • Jakub Karczewski
    • Jacek Ryl
    • Grzegorz Cempura
    • Marcin Zając
    • Maciej Bik
    • Maciej Sitarz
    • Piotr Jasiński
    • Sebastian Molin
    2023 Pełny tekst INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

    To study the effect of partial Co substitution by Fe in the B site of MnCo2O4 spinel on its physicochemical and electrochemical properties, a series of MnCo2-xFexO4 powders (x=0.125; 0.250; 0.500; 0.750; 1.000) were synthesized by means of the sol-gel method. The produced powders were characterized by powder X ray diffraction (pXRD), scanning and transmission electron microscopy (SEM & TEM) coupled with energy dispersive spectroscopy (EDS), X ray photoelectron and absorption spectroscopy (XPS & XAS), Fourier transformed infrared spectroscopy (FTIR), and inductively coupled plasma optical emission spectroscopy (ICP OES). The electrocatalytic activity towards oxygen evolution reaction (OER) was evaluated in an alkaline environment (0.1 M KOH). From our findings, the activity increased with the addition of Fe up to x = 0.5, characterized by a decrease of overpotential at 10 mA cm-2GEO from 406 mV for MnCo2O4 to 376 mV for MnCo1.5Fe0.5O4, with a corresponding 44 mV dec 1 Tafel slope. It was identified that the OER-specific activity exhibits a volcano-type shape as a function of the eg occupancy at octahedral sites tuned by Co substitution with Fe.

  • Tuning of the plasmon resonance location in Au nanostructures coated with a ultrathin film of Al2O3 – Optical measurements and FDTD simulations
    • Marcin Łapiński
    • Robert Kozioł
    • Paweł Syty
    • Sergiusz Patela
    • Józef Sienkiewicz
    • Wojciech Sadowski
    • Barbara Kościelska
    2023 SURFACE SCIENCE

    The Au nanostructures have been coated with an ultra-thin films of amorphous aluminium oxide. Optical absorption spectra show the influence of the thickness of Al2O3 on plasmon resonance wavelength. The observed red-shift of the resonance location with the increase of the thickness of the Al2O3 film, can be explained by the change in the dielectric function of this film. It allows control of the optical spectra of the coated particles. In this paper we present a two ways for determinaton of optical paramaters of aluminium oxide ultra-thin films. The first one is based on a ellipsometry method, while in second approach a shift of plasmon resonance is used for computer simulations of films. The experimental data are in agreement with the results of the FDTD calculations, showing the possibility of both determining such a function for ultra-thin layers by the computer simulation method, as well as predicting the value of the dielectric constant depending on the thickness of the layer. The experimental data needed for the simulation was obtained in studies such as XRD, XPS, SEM and HR TEM. The proposed models can help to adjust the coating thickness to the desired plasmon resonance position.

  • Tutoring - dlaczego edukacja spersonalizowana ma sens
    • Aneta Sobiechowska-Ziegert
    • Katarzyna Kubiszewska
    2023 Pismo PG

    W artykule autorki przedstawiają koncepcję tutoringu akademickiego. Ostatnie lata przyniosły wzmożone zainteresowanie nowymi formami pracy z uczniem. Wielu specjalistów z zakresu edukacji twierdzi, że osiąganie wysokich rezultatów jest możliwe, ale wymaga zindywidualizowanej pracy z drugą osobą. Tutoring wpisuje się właśnie w ten nurt zindywidualizowanej pracy i relacji mistrz - student.

  • Tweet you right back: Follower anxiety predicts leader anxiety in social media interactions during the SARS-CoV-2 pandemic
    • Alexandros Psychogios
    • Dritjon Gruda
    • Adegboyega Ojo
    2023 Pełny tekst PLOS ONE

    Recent research has shown that organizational leaders’ tweets can influence employee anxiety. In this study, we turn the table and examine whether the same can be said about followers’ tweets. Based on emotional contagion and a dataset of 108 leaders and 178 followers across 50 organizations, we infer and track state- and trait-anxiety scores of participants over 316 days, including pre- and post the onset of the SARS-CoV-2 pandemic and crisis. We show that although leaders traditionally possess greater authority and power than their followers, followers have the power to influence their leaders’ state anxiety. In addition, this influence is particularly strong in the case of less trait anxious leaders.

  • Two-body dissociation of isoxazole following double photoionization – an experimental PEPIPICO and theoretical DFT and MP2 study
    • Tomasz Wąsowicz
    • Iwona Dąbkowska
    • Antti Kivimäki
    • Robert Richter
    2023 Pełny tekst PHYSICAL CHEMISTRY CHEMICAL PHYSICS

    The dissociative double photoionization of isoxazole molecules has been investigated experimentally and theoretically. The experiment has been carried out in the 27.5–36 eV photon energy range using vacuum ultraviolet (VUV) synchrotron radiation excitation combined with ion time-of-flight (TOF) spectrometry and photoelectron–photoion–photoion coincidence (PEPIPICO) technique. Five wellresolved two-body dissociation channels have been identified in the isoxazole’s coincidence maps, and their appearance energies have been determined. The coincidence yield curves of these dissociation channels have been obtained in the photon energy ranges from their appearance energies up to 36 eV. The double photoionization of isoxazole produces a C3H3NO2+ transient dication, which decomposes into fragments differing from previously reported photofragmentation products of isoxazole. We have found no evidence of pathways leading to the C3H2NO+, HCN+, C2H2O+, C3HN+, or C2H2 + fragments or their neutral counterparts that have been observed in previous neutral photodissociation and single photoionization studies. Instead, the dissociation of isoxazole after the ejection of two electrons is bond-selective and is governed by two reactions, HCO+ + H2CCN+ and H2CO+ + HCCN+, whose appearance energies are 28.6 (0.3) and 29.4 (0.3) eV, respectively. A third dissociation channel turns out to be a variant of the most intense channel (HCO+ + H2CCN+), where one of the fragment ions contains a heavy isotope. Two minor dissociation channels occurring at higher energies, CO+ + CH3CN+ and CN+ + H3CCO+, are also identified. The density functional and ab initio quantum chemical calculations have been performed to elucidate the dissociative charge-separating mechanisms and determine the energies of the observed photoproducts. The present work unravels hitherto unexplored photodissociation mechanisms of isoxazole and thus provides deeper insight into the photophysics of five-membered heterocyclic molecules containing two heteroatoms.

  • Udział społeczeństwa w procedurze planowania przestrzennego – analiza metod i technik konsultacji społecznych na przykładzie polskich małych i średnich miast w ramach projektu POWER
    • Barbara Zgórska
    • Marta Jaskulska
    2023 Pełny tekst Space-Society-Economy

    Udział społeczeństwa w procesie opracowywania aktów planowania przestrzennego w Polsce ma charakter informacyjny, a nie dialogiczny, co przyczynia się m.in. do jego konfliktogenności. W latach 2016–2021 zrealizowano ogólnokrajowy projekt POWER dofinansowany ze środków Unii Europejskiej, którego celem było m.in. przetestowanie angażujących metod i technik konsultacji społecznych, zwiększenie poziomu współdecydowania i poprawa metod rozwiązywania konfliktów w planowaniu przestrzennym na poziomie gminnym.Artykuł zawiera ocenę metod i technik konsultacyjnych zastosowanych w 83 małych i średnich miastach, które uczestniczyły w projekcie POWER, opis najczęściej wykorzystywanych metod i technik, sposobów ich łączenia oraz trzy studia przypadków analizowanych pod kątem możliwości wyeliminowania potencjalnych konfliktów.Badanie przeprowadzono z wykorzystaniem metod ilościowych i jakościowych: desk research, obserwacja, obserwacja uczestnicząca, ankieta.

  • UKŁAD REGULACJI MOCY DUŻEJ FARMY FOTOWOLTAICZNEJ
    • Mirosław Włas
    • Konrad Seklecki
    • Kacper Chyła
    2023 Pełny tekst

    W dniu 17 maja 2016 r. weszło w życie Rozporządzenie Komisji (UE) 2016/631 z dnia 14 kwietnia 2016 r. ustanawiające kodeks sieci dotyczący przyłączenia jednostek wytwórczych [3]. Na podstawie tego dokumentu i Prawa Energetycznego OSP i OSD przygotowało wymogi w zakresie przyłączania jednostek wytwórczych do sieci energetycznej. Moduły wytwarzania B, C i D powinny posiadać możliwość regulacji mocy czynnej i biernej. Niniejszy artykuł przedstawia wdrożenie wymagań Kodeksu Sieci NC RfG dla farmy fotowoltaicznej o mocy 60MWp

  • ULEPSZONE SKALOWANIE W NIEREDUNDANCYJNEJ ARYTMETYCE RESZTOWEJ
    • Robert Smyk
    • Maciej Czyżak
    2023

    Przedstawiono nowy algorytm rozszerzania bazy w resztowym systemie liczbowym bez użycia nadmiarowego modułu. Rozszerzanie bazy jest kluczową operacją w wielu zastosowaniach, gdzie używany jest resztowy system liczbowy, takich jak cyfrowe przetwarzanie sygnałów, jak też implementacja systemu szyfrowania algorytmem Rivesta-Shamira-Adlemana (RSA). Ortogonalne projekcje występujące w chińskim twierdzeniu o resztach dla modułu, o który jest rozszerzana baza systemu resztowego, przechowywane są w niewielkich pamięciach typu ROM (ang. Read-Only Memory) w formie resztowej. Projekcje te są sumowane w sumatorze binarnym i otrzymana suma jest redukowana dla modułu, o który rozszerzana jest baza. Metoda wykorzystuje nowy i efektywny algorytm obliczania współczynnika nadmiaru w chińskim twierdzeniu o resztach. Umożliwia ona wielokrotną redukcję złożoności sprzętowej.

  • Ultra-Compact SIRC-Based Self-Triplexing Antenna with High Isolation
    • Rusan Kumar Barik
    • Sławomir Kozieł
    2023 Pełny tekst Electronics

    An ultra-compact self-triplexing antenna realized on a substrate-integrated rectangular cavity (SIRC) is discussed in this study. The proposed structure employs two L-shaped slots and an in-verted U-shaped slot to radiate at three independent operating frequency bands. Three 50-ohm microstrip feed lines are used to excite the radiation in these slots. The operating frequency is individually tuned using the slot size. The slot placement and size are designed having in mind obtaining one or more frequency bands below the SIRC cutoff frequency, which has the ad-vantage of enabling ultra-compact size. High port isolations are achieved by applying one of the ports orthogonally to the two remaining ones, which creates a weak cross-coupling channel. A lumped-circuit model is created to examine the antenna operation. The presented design has been prototyped and experimentally validated with the measured operating frequencies of 1.92 GHz, 4.43 GHz, and 5.25 GHz for GSM, 5G, and WLAN applications, respectively. The port isola-tions are better than 32.4 dB according to both EM simulations and measurements. Meanwhile, the measured realized gain of the antenna is better than 4.3 dBi at all bands.

  • Ultrasound assisted dispersive solid phase microextraction using polystyrene-polyoleic acid graft copolymer for determination of Sb(III) in various bottled beverages by HGAAS
    • Nail Altunay
    • Baki Hazer
    • Muhammad Farooque Lanjwani
    • Mustafa Tuzen
    • Hameed Haq
    • Grzegorz Boczkaj
    2023 FOOD CHEMISTRY

    A new polyoleic acid-polystyrene (PoleS) block/graft copolymer was synthesized and applied as adsorbent for ultrasound assisted dispersive solid phase microextraction (UA-DSPME) of Sb(III) in different bottled beverages and analysis using hydride generation atomic absorption spectrometry (HGAAS). Adsorption capacity of the PoleS was 150 mg g−1. Several sample preparation parameters such as sorbent amount, solvent type, pH, sample volume and shaking time were optimized (based on central composite design (CCD) approach) and evaluated in respect to the recovery of Sb(III). The method revealed a high tolerance limit of matrix ions presence. Under optimized conditions, linearity range, the limit of detection, the limit of quantitation, extraction recovery, enhancement factor, preconcentration factor were 5–800 ng L−1, 1.5 ng L−1, 5.0 ng L−1, 96%, 82, 90, respectively. Accuracy of the UA-DSPME method was confirmed based on different certified reference materials and standard addition method. Factorial design was utilized to estimate the influences of variables of recovery of Sb(III).

  • Uncertainty of Postmortem Time Estimation Based on Potassium Ion Determination in Vitreous Humor Using Potentiometric Ion-Selective Electrode and Microwave-Induced Plasma with Optical Emission Spectrometry Methods
    • Sonia Zięba
    • Marek Wiergowski
    • Bartłomiej Cieślik
    • Sein Anand Jacek
    • Marta Krzyżanowska
    2023 Pełny tekst Separations

    There is a need for a reliable and independent evaluation and confirmation of the post-mortem interval (PMI) based on objective factors other than only postmortem changes or temperature measurements. Estimating the PMI by examining the concentration of potassium ions in the vitreous humor (VH) has a tradition in forensic toxicology dating back to the mid-20th century. So far, the methods for determining the presence of potassium ions have not been characterized in terms of the measurement uncertainty of types A and B, which directly affect the estimation of time of death uncertainty. The study evaluated the uncertainty of the determination of potassium ion concentra- tions using potentiometric ion-selective electrode (ISE) and microwave-induced plasma with optical emission spectrometry (MIP-OES) methods. In addition, the influence of the estimated measurement uncertainty on the results of the analysis of potassium ions in the VH was investigated. The estimated values of the expanded uncertainty determined by the type A experimental method indicate lower uncertainty in the determination of potassium ion concentration in the case of MIP-OES than ISE; that is, for concentrations of 2, 10, and 25 mg/L of potassium ions, the expanded uncertainties by MIP-OES were 1.2%, 2.2%, and 2.5% and the uncertainties by ISE were 12.2%, 6.1%, and 3.1%, respectively. Similarly, in the case of estimating the uncertainty of type B, the MIP-OES method compared to ISE was characterized by almost two times lower expanded uncertainty; that is, for MIP-OES, it was 2.53%, and for ISE, it was 4.75%. Both methods of uncertainty estimation, types A and B, can be used interchangeably, as they provide comparable results.

  • Uncertainty Quantification of Additive Manufacturing Post-Fabrication Tuning of Resonator-Based Microwave Sensors
    • Sławomir Kozieł
    • Tanveer Haq Ul
    2023 MEASUREMENT

    Reconfigurability, especially in terms of the ability of adjusting the operating frequency, has become an important prerequisite in the design of modern microwave components and systems. It is also pertinent to microwave sensors developed for a variety of applications such as characterization of material properties of solids or liquids. This paper discusses uncertainty quantification of additive-manufacturing-based post-fabrication tuning of resonator-based sensors implemented using a microstrip technology. Therein, the operating frequency is altered by adding metallic patches of a specific size determined by the full-wave electromagnetic (EM) model of the system. The reliability of setting up the center frequency depends on both the accuracy of the patch size (manually cut out of the copper tape), and its allocation with respect to the resonator. A rigorous statistical analysis of the patch size and its allocation errors is carried out, including a quantification of their joint effects on the sensor operating frequency. Furthermore, the analysis of a possibility of compensating the patch size inaccuracies through its appropriate positioning is conducted. The details of the proposed approach are explained using a complementary symmetric split ring resonator (CSSRR)-based sensor designed to operate in X and Ku bands with the tuning range between 10 GHz and 20 GHz. The optimized sensor's fundamental resonant frequency is 9.4 GHz, its exterior size is 25 x 30 mm2, the quality factor of the fabricated sensor is 29, and the sensitivity of the considered design is 1.1 GHz/mm with the measurement error is 0.1 percent. The obtained measurement data are indicative of a practical utility of the additive-manufacturing-based tuning technique, in particular, a possibility of reliable center frequency tuning under mild assumptions on the accuracy of manual preparation of the tuning patches. Furthermore, a practical tuning scheme has been developed and experimentally validated, which allows for a precise allocation of the operating frequency with the error not exceeding 0.01 GHz (or 0.1% in relative terms), all under assumptions of a manual preparation and placement of the tuning patch.

  • Underground Water Level Prediction in Remote Sensing Images Using Improved Hydro Index Value with Ensemble Classifier
    • Andrzej Stateczny
    • Sujatha Canavoy Narahari
    • Padmavathi Vurubindi
    • Nirmala S. Guptha
    • Kalyanapu Srinivas
    2023 Pełny tekst Remote Sensing

    The economic sustainability of aquifers across the world relies on accurate and rapid estimates of groundwater storage changes, but this becomes difficult due to the absence of insitu groundwater surveys in most areas. By closing the water balance, hydrologic remote sensing measures offer a possible method for quantifying changes in groundwater storage. However, it is uncertain to what extent remote sensing data can provide an accurate assessment of these changes. Therefore, a new framework is implemented in this work for predicting the underground water level using remote sensing images. Generally, the water level is defined into five levels: Critical, Overexploited, Safe, Saline, and Semi-critical, based on water quantity. In this manuscript, the remote sensing images were acquired from remote sensing images. At first, Wiener filtering was employed for preprocessing. Secondly, the Vegetation Indexes (VI) (Normalized Difference Vegetation Index (NDVI), Normalized Difference Snow Index (NDSI), Infrared index (IRI), Radar Vegetation Index (RVI)), and statistical features (entropy, Root Mean Square (RMS), Skewness, and Kurtosis) were extracted from the preprocessed remote sensing images. Then, the extracted features were combined as a novel hydro index, which was fed to the Ensemble Classifier (EC): Neural Networks (NN), Support Vector Machine (SVM), and improved Deep Convolutional Neural Network (DCNN) models for underground water level prediction in the remote sensing images. The obtained results prove the efficacy of the proposed framework by using different performance measures. The results shows that the False Positive Rate (FPR) of the proposed EC model is 0.0083, which is better than that of existing methods. On the other hand, the proposed EC model has a high accuracy of 0.90, which is superior to the existing traditional models: Long Short-Term Memory (LSTM) network, Naïve Bayes (NB), Random Forest (RF), Recurrent Neural Network (RNN), and Bidirectional Gated Recurrent Unit (Bi-GRU).

  • Understanding Fuel Saving and Clean Fuel Strategies Towards Green Maritime
    • Van Nhanh Nguyen
    • Krzysztof Rudzki
    • Marek Dzida
    • Nguyen Dang Khoa Pham
    • Minh Tuan Pham
    • Phuoc Quy Phong Nguyen
    • Phuong Nguyen Xuan
    2023 Pełny tekst Polish Maritime Research

    Due to recent emission-associated regulations imposed on marine fuel, ship owners have been forced to seek alternate fuels, in order to meet the new limits. The aim of achieving low-carbon shipping by the year 2050, has meant that alternative marine fuels, as well as various technological and operational initiatives, need to be taken into account. This article evaluates and examines recent clean fuels and novel clean technologies for vessels. The alternative fuels are classified as low-carbon fuels, carbon-free fuels, and carbon neutral fuels, based on their properties. Fuel properties, the status of technological development, and existing challenges are also summarised in this paper. Furthermore, researchers have also investigated energy-saving devices and discovered that zero-carbon and virtually zero-carbon clean fuels, together with clean production, might play an important part in shipping, despite the commercial impracticability of existing costs and infrastructure. More interestingly, the transition to marine fuel is known to be a lengthy process; thus, early consensus-building, as well as action-adoption, in the maritime community is critical for meeting the expectations and aims of sustainable marine transportation

  • Understanding Sustainable Knowledge-Sharing in Agile Projects: Utilizing Follow-the-Sun Technique (FTS) in Virtual Teams
    • Edward Szczerbicki
    • Rodrigo Oliveira de Castro
    • Cesar Sanin
    2023 Pełny tekst

    In Agile IT projects, promoting effective knowledge sharing is essential not only for achieving success but also for supporting Sustainable Development Goals (SDGs). However, Companies using virtual teams may face challenges in coordinating work, particularly when teams are distributed across different time zones, ultimately hindering their ability to consistently share knowledge. This can lead to delays and inefficiencies, ultimately impacting the project outcomes and the organization's profitability. To ensure sustainable knowledge sharing, a comprehensive framework is necessary that addresses the environmental, social, economic, and political aspects of the project. This paper proposes a framework that combines the Follow-the-Sun (FTS) technique and the Sustainable Knowledge Sharing Model, enabling 24-hour knowledge sharing in virtual teams and benefiting IT agile projects.

  • Understanding the kinetics and atmospheric degradation mechanism of chlorotrifluoroethylene (CF2=CFCl) initiated by OH radicals
    • Saber Safari Balsini
    • Abolfazl Shiroudi
    • Farhad Hatamjafari
    • Ehsan Zahedi
    • Khalil Pourshamsian
    • Ahmad Reza Oliaey
    2023 PHYSICAL CHEMISTRY CHEMICAL PHYSICS

    The atmospheric degradation of chlorotrifluoroethylene (CTFE) by OH˙ was investigated using density functional theory (DFT). The potential energy surfaces were also defined in terms of single-point energies derived from the linked cluster CCSD(T) theory. With an energy barrier of −2.62 to −0.99 kcal mol−1 using the M06-2x method, the negative temperature dependence was determined. The OH˙ attack on Cα and Cβ atoms (labeled pathways R1 and R2, respectively) shows that reaction R2 is 4.22 and 4.42 kcal mol−1, respectively, more exothermic and exergonic than reaction R1. The main pathway should be the addition of OH˙ to the β-carbon, resulting in ˙CClF–CF2OH species. At 298 K, the calculated rate constant was 9.87 × 10−13 cm3 molecule−1 s−1. The TST and RRKM calculations of rate constants and branching ratios were performed at P = 1 bar and in the fall-off pressure regime over the temperature range of 250–400 K. The formation of HF and ˙CClF–CFO species via the 1,2-HF loss process is the most predominant pathway both kinetically and thermodynamically. With increasing temperature and decreasing pressure, the regioselectivity of unimolecular processes of energized adducts [CTFE–OH]˙ gradually decreases. Pressures greater than 10−4 bar are often adequate for assuring saturation of the estimated unimolecular rates when compared to the RRKM rates (in high-pressure limit). Subsequent reactions involve the addition of O2 to the [CTFE–OH]˙ adducts at the α-position of the OH group. The [CTFE–OH–O2]˙ peroxy radical primarily reacts with NO and then directly decomposes into NO2 and oxy radicals. “Carbonic chloride fluoride”, “carbonyl fluoride”, and “2,2-difluoro-2-hydroxyacetyl fluoride” are predicted to be stable products in an oxidative atmosphere.

  • Universities’ journey towards sustainability- systematic literature review
    • Magdalena Popowska
    • Monika Sady
    2023 Pełny tekst International Journal of Sustainability in Higher Education

    Purpose: This research aims to identify a sustainable university's key features. It is an essential step in tracing the topics discussed in the context of a sustainable university and their evolution in the scientific discourse. Design/methodology/approach: This paper relies on a systematic literature review (SLR) conducted using two scholarly databases: Emerald and Scopus. The timeframe selected by the authors for reviewing the available sources spans from 2001 to 2021. Findings: The analysis distinguished seven sustainable university categories, each revealing critical features of sustainable higher education. Each of these categories represents an intriguing area for in-depth analysis. The systematic literature review (SLR) reveals gaps requiring further scientific exploration. Originality: SLR is a cornerstone of research synthesis and helps integrate scientific evidence from qualitative and quantitative published studies. Conducted research presents knowledge about university sustainability and can help scientists find research gaps. Research limitations/implications: The performed literature review was determined by the choice of entries (keywords) to identify the scientific papers in the selected databases. Moreover, since the authors aimed to focus on peer-reviewed sources, this SLR did not include books and doctoral dissertations dealing with the studied issues. The results of the analysis can be used practically by both researchers and practitioners in the field of sustainable development. Identified scientific gaps become a potential research field, and practitioners interested in the transition toward sustainable development (SD) may contribute by accompanying universities in this journey. Collaboration and networking with business stakeholders are critical vectors for spreading the idea of SD. Society's growing concern for climate change requires accurate and specific actions from institutions. As entities educating future generations, universities have a unique role in transforming toward SD. Our findings allow us to get acquainted with the existing main activities undertaken by HEIs in this field and understand the importance of this topic for researchers.

  • Unlocking the Secrets of River Pollution: Analyzing Organic Pollutants in Sediments—Experimental Study
    • Sadeq Abdullah Abdo Alkhadher
    • Suhaimi Suratman
    • Hussein Al-Hazmi
    • Mohamad Pauzi Zakaria
    • Bartosz Szeląg
    • Joanna Majtacz
    • Jakub Drewnowski
    2023 Pełny tekst Water

    Untreated wastewater released into rivers can result in water pollution, the spread of waterborne diseases, harm to ecosystems, contamination of soil and groundwater, as well as air pollution and respiratory problems for nearby humans and animals due to the release of greenhouse gases. The current study aims to investigate the recent input of anthropogenic loads into the rivers using linear alkylbenzene (LAB), which is one of the molecular chemical markers with application of sophisticated model statistical analyses. In order to determine the compositions of LABs, which act as wastewater pollution molecular indicators, surface sediment samples from the Muar and Kim Kim rivers were collected. Gas chromatography-mass spectrometry (GC-MS) was utilized to identify LABs and investigate their sources and degradation. ANOVA and the Pearson correlation coefficient were employed to determine the significance of differences between sampling locations, with a threshold of p < 0.05. To assess the degradation degree and efficacy of wastewater treatment plants (WWTPs), LABs were identified based on chains ranging from long to short (L/S), C13/C12 homolog, and internal to external (I/E) congeners. The results indicated that LAB concentrations in the studied areas of the Muar River ranged from 87.4 to 188.1 ng g−1dw. There were significant differences in LAB homology at p < 0.05, and a significant percentage of sampling stations contained C13-LAB homology. Based on the LAB ratios (I/E) determined, which ranged from 1.7 to 2.2 in the studied areas, it was concluded that effluents from primary and secondary sources are being discharged into the marine ecosystem in those areas. The degradation of LABs was up to 43% in the interrogated locations. It can be inferred that there is a requirement for enhancing the WWTPs, while also acknowledging the efficacy of LAB molecular markers in identifying anthropogenic wastewater contamination.

  • Unprecedented Adhesive Performance of Propylene-Based Hydroxyl Functionalized Terpolymers
    • Jakub Kruszyński
    • Weronika Nowicka
    • Miloud Bouyahyi
    • Yingxin Liu
    • Lanti Yang
    • Artur Rozanski
    • Nithish Anbuchezhian
    • Lidia Jasińska-Walc
    • Rob Duchateau
    2023 ACS Applied Polymer Materials

    The synthesis of hydroxyl functionalized propylene-based terpolymers and their performance as hot melt adhesives were investigated. The products comprise uniformly distributed butyl and 4-hydroxyl-butyl branches along the polypropylene backbone. Despite the low hydroxyl-functionality level of ≤ 0.5 mol%, hydroxyl functionalized terpolymers show formidable adhesion to aluminum and steel providing an adhesive strength exceeding 16 MPa, whereas the non-functionalized congeners hardly adhere to these metals. As evidenced by rheological measurements, the functional groups form dynamic cross-links based on hydrogen bonding and electrostatic interactions with aluminum oxide hydroxide residues, remaining in the product after polymerization. At the industrial application temperature of 180 °C, non-deashed and deashed samples of polymers having 0.1 mol% or 0.5 mol% of incorporated 5-hexen-1-ol gave, upon cooling to room temperature, comparable adhesive strengths. Deashing and increasing the functionality level leads to a significant improvement of the adhesion strength at lower application temperature (130 °C), allowing application of the hydroxyl functionalized propylene-based terpolymers as high strength hot melt adhesive for combinations of polypropylene and metals.

  • Unraveling a novel microwave strategy to fabricate exposed {001}/{101} facets anatase nanocrystals: Potential for use to the elimination of environmentally toxic metronidazole waste
    • Adam Kubiak
    • Anna Grzegórska
    • Elżbieta Gabała
    • Joanna Zembrzuska
    • Anna Zielińska-Jurek
    • Michał Cegłowski
    2023 MATERIALS RESEARCH BULLETIN

    This study present a novel microwave strategy to fabricate highly active anatase particles, exposing {101} and {001} facets. Microwave treatment time was shown to determine the growth of crystals in a certain direction. To the best of our knowledge, it is the first report revealing that the contact time of TiO2 crystals with fluorine ions during the microwave process affects the formed morphology, in particular exposed facets ratio. The important element of this study was a parallel approach to produce active photocatalysts and a convenient UV-LED light source. The simultaneous use of synthesized anatase nanocrystals with exposed {001}/{101} facets and tailormade LED photoreactor led to the enhanced elimination of metronidazole. Photocatalytic studies showed greater activity in the elimination of metronidazole with increasing microwave exposure time, which was associated with the presence of the surface heterojunction {001}/{101}, leading to better separation of charge carriers.

  • Unraveling the Interplay between DNA and Proteins: A Computational Exploration of Sequence and Structure-Specific Recognition Mechanisms
    • Kazi Hossain
    2023 Pełny tekst

    My PhD dissertation focused on DNA-protein interactions and the recognition of specific DNA sequences and structures. I discovered that acidic amino acid residues (Asp/Glu) play a crucial role by exhibiting a preference for cytosine. Their contribution to binding affinity depends on nearby cytosines, balancing electrostatic repulsion with specific interactions. Acidic residues act as negative selectors, discouraging non-cytosine binding, but can be favorable with increasing proximal cytosine count. They exclusively recognize cytosine due to electrostatic repulsion with adenine's N7 atom and stronger hydrogen bonding. In another aspect of my research, I explored conformation-specific DNA recognition. I found that the EXOG protein prefers A-DNA and selectively recognizes RNA/DNA chimeric duplexes. Specific arginine residues induce the A-DNA conformation when EXOG binds to DNA/DNA duplexes, providing insights into mitochondrial replication and base excision repair. Furthermore, I investigated the DHX36 helicase, which recognizes G-quadruplexes (G4s) through its DSM and OB subdomains. The planar face of a G-tetrad and the specific backbone conformation of a G-tract are critical features in this interaction. The DSM and OB subdomains cooperatively recognize these distinctive features of parallel G4s. Importantly, the recognition by DSM is mediated through van der Waals contacts and hydrophobic interactions, exhibiting a preference for the accessible 5'-side of the G4 structure.

  • UNRES-GPU for Physics-Based Coarse-Grained Simulations of Protein Systems at Biological Time- and Size-Scales
    • Krzysztof Ocetkiewicz
    • Cezary Czaplewski
    • Henryk Krawczyk
    • Agnieszka Lipska
    • Józef Liwo
    • Jerzy Proficz
    • Adam Sieradzan
    • Paweł Czarnul
    2023 Pełny tekst BIOINFORMATICS

    The dynamics of the virus like particles (VLPs) corresponding to the GII.4 Houston, GII.2 SMV, and GI.1 Norwalk strains of human noroviruses (HuNoV) that cause gastroenteritis was investigated by means of long-time (about 30 μs in the laboratory timescale) molecular dynamics simulations with the coarse-grained UNRES force field. The main motion of VLP units turned out to be the bending at the junction between the P1 subdomain (that sits in the VLP shell) and the P2 subdomain (that protrudes outside) of the major VP1 protein, this resulting in a correlated wagging motion of the P2 subdomains with respect to the VLP surface. The fluctuations of the P2 subdomain were found to be more pronounced and the P2 domain made a greater angle with the normal to the VLP surface for the GII.2 strain, which could explain the inability of this strain to bind the histo-blood group antigens (HBGAs).

  • Unveiling the Green Mirage: Unearthing Weaknesses in Pro-Environmental Applications
    • Ewa Duda
    • Hanna Obracht-prondzyńska
    • Helena Anacka
    • Jolanta Kowal
    2023 Pełny tekst

    Growing ecological concerns and a general shift towards tailored digitized solutions in cities lead to an increased popularity of pro ecological applications, especially those associated with transport-oriented functionalities. This research focuses on the results from a testbed of a pro-environmental application deployment among early adopters. Based on quantitative and cartographic analysis enriched with interviews’ results, by applying a triangulation research approach, we are able to answer three research questions: related to potential constraints or unintended negative outcomes of pro-environmental educational applications, deviation from the intended use of these apps, as well as range of climate- responsive behaviors these applications promote. Research results allow us to analyze to what extent a pro environmental application affects users’ behavior and ecological choices. It also helps to critically evaluate potential technological weaknesses, their interaction with end users and an impact on motivations and habits of urban dwellers.

  • Unveiling the Pool of Metallophores in Native Environments and Correlation with Their Potential Producers
    • Francisco Calderón Celis
    • Ivan González-Álvarez
    • Magdalena Fabjanowicz
    • Simon Godin
    • Laurent Ouerdane
    • Béatrice Lauga
    • Ryszard Łobiński
    2023 ENVIRONMENTAL SCIENCE & TECHNOLOGY

    For many organisms, metallophores are essential biogenic ligands that ensure metal scavenging and acquisition from their environment. Their identification is challenging in highly organic matter rich environments like peatlands due to low solubilization and metal scarcity and high matrix complexity. In contrast to common approaches based on sample modification by spiking of metal isotope tags, we have developed a two-dimensional (2D) Solid-phase extraction-Liquid chromatography-mass spectrometry (SPE-LC-MS) approach for the highly sensitive (LOD 40 fmol per g of soil), high-resolution direct detection and identification of metallophores in both their noncomplexed (apo) and metal-complexed forms in native environments. The characterization of peat collected in the Bernadouze (France) peatland resulted in the identification of 53 metallophores by a database mass-based search, 36 among which are bacterial. Furthermore, the detection of the characteristic (natural) metal isotope patterns in MS resulted in the detection of both Fe and Cu potential complexes. A taxonomic-based inference method was implemented based on literature and public database (antiSMASH database version 3.0) searches, enabling to associate over 40% of the identified bacterial metallophores with potential producers. In some cases, low completeness with the MIBiG reference BCG might be indicative of alternative producers in the ecosystem. Thus, coupling of metallophore detection and producers’ inference could pave a new way to investigate poorly documented environment searching for new metallophores and their producers yet unknown.

  • Upgrading low value-added activities in global value chains: a functional specialisation approach
    • Aleksandra Kordalska
    • Magdalena Olczyk
    2023 Pełny tekst Economic Systems Research

    This paper aims to identify patterns of functional specialisation (FS) in global value chains (GVCs) and determinants of upgrading them for selected Central Eastern European (CEE) economies. By combing the World Input-Output Database with data on occupations, we reveal a new FS pattern among subgroups of CEEs. Poland and Slovakia have an unfavourable GVC position and specialise in low value-added fabrication function. In contrast, other CEEs have competitive advantages in high value-added tasks: the Baltic countries and Slovenia in management services, the Czech Republic and Slovenia in R&D. We identify upgrading factors for different types of FS in GVCs. The wages convergence of CEEs with developed economies, and strong GVC backward linkages support the path to higher value-added in almost all business functions. Higher GDP per capita and lower economic distance to Germany allow CEEs to escape from ‘factory economies' status and also generate higher value-added in R&D activities.

  • Upoważnienie do zaciągania zobowiązań na rzecz jednostek samorządu terytorialnego jako naruszenie dyscypliny finansów publicznych
    • Alicja Sekuła
    • Grzegorz Garbacz
    2023 Pełny tekst ZESZYTY PRAWNICZE BIURA ANALIZ SEJMOWYCH

    Artykuł poświęcony jest zagadnieniu upoważnienia do zaciągania zobowiązań na rzecz jednostek samorządu terytorialnego. W teoretycznej części zdefiniowano dwa pojęcia: zobowiązań oraz zaciągania zobowiązań. Następnie scharakteryzowano zagadnienie podmiotowego i przedmiotowego zaciągania zobowiązań. Nieprzestrzeganie przepisów dotyczących zaciągania zobowiązań, które zawarte są głównie w ustawie o finansach publicznych, prowadzi do naruszenia dyscypliny finansów publicznych. Problematykę tę przeanalizowano z punktu widzenia naruszenia dyscypliny finansów publicznych w związku z zaciąganiem zobowiązań. W części empirycznej artykułu omówiono trzy studia przypadków, tzn. opisano wyroki Głównej Komisji Orzekającej w sprawach o naruszenie dyscypliny finansów publicznych, dotyczące niezgodnego z prawem zaciągania zobowiązań.