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Politechniki Gdańskiej

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  • Chemical Pressure Tuning Magnetism from Pyrochlore to Triangular Lattices
    • Ranuri S. Dissanayaka Mudiyanselage
    • Tomasz Klimczuk
    • Danrui Ni
    • Robert J. Cava
    • Weiwei Xie
    2022 INORGANIC CHEMISTRY

    Geometrically frustrated lattices combined with magnetism usually host quantum fluctuations that suppress magnetic orders and generate highly entangled ground states. Three-dimensionally (3D) frustrated magnets generally exist in the diamond and pyrochlore lattices, while two-dimensionally (2D) frustrated geometries contain Kagomé, triangular, and honeycomb lattices. In this work, we reported using chemical pressure to tune the magnetism of the pyrochlore lattice in LiYbSe2 into a triangular lattice by doping Ga or In. Li3−xGaxYb3Se6 and Li3−xInxYb3−yInySe6/Li3−xInxYb3−y□ySe6 crystallize in a trigonal α-NaFeO2 structure-type (space group R3̅m) and can be synthesized using either LiCl or Se flux. In Li3−xGaxYb3Se6, Ga3+ and Li+ are mixed, leaving Yb3+ on the triangular plane. Instead of just Li+ being replaced in Li3−xGaxYb3Se6, In3+ was observed in both the Li+ and Yb3+ layers in Li3−xInxYb3−yInySe6 depending on the reaction conditions. Dominant antiferromagnetic interactions are revealed by magnetic measurements in both Li3−xGaxYb3Se6 and Li3−xInxYb3−yInySe6/ Li3−xInxYb3−y□ySe6. However, no long-range magnetic order is detected in thermomagnetic measurements above 1.8 K due to geometrical frustration. Thus, Li3−xGaxYb3Se6, Li3−xInxYb3−yInySe6/Li3−xInxYb3−y□ySe6, and the LiYbSe2 previously discovered by our group provide an ideal platform to understand the complex structure−magnetism correlations from 3D to 2D frustrated lattices.

  • Chemometric Evaluation of WWTPs’ Wastewaters and Receiving Surface Waters in Bulgaria
    • Veronika Mihaylova
    • Galina Yotova
    • Błażej Kudłak
    • Tony Venelinov
    • Tsakovski Stefan
    2022 Pełny tekst Water

    Wastewater treatment plant (WWTP) installations are designed and operated to reduce the quantity of pollutants emitted to surface waters receiving treated wastewaters. In this work, we used classical instrumental studies (to determine chemicals and parameters under obligations put with Directive 91/271/EEC), ecotoxicological tools (Sinapis alba root growth inhibition (SA-RG) and Heterocypris incongruens mortality (MORT) and growth inhibition (GRINH)) and multivariate statistical analysis to gain information on feature profiles of WWTPs’ effluents and the possible burden of surface water bodies receiving treated wastewaters in eleven locations of Bulgaria. Initial screening of results has shown that only phosphorus content exceeds the admissible level in 5 out 11 WWTP effluents, while As, Cr, Cu, Mn, and Zn show exceedance at several locations. The multivariate statistical analysis reveals the discriminating water quality parameters and outlines the ability of Heterocypris incongruens to evaluate the ecotoxicological potential of different groups of waters.

  • Chitin and derivative chitosan-based structures — Preparation strategies aided by deep eutectic solvents: A review
    • Mohammad Khajavian
    • Vahid Vatanpour
    • Roberto Castro-Muñoz
    • Grzegorz Boczkaj
    2022 Pełny tekst CARBOHYDRATE POLYMERS

    The high molecular weight of chitin, as a biopolymer, challenges its extraction due to its insolubility in the solvents. Also, chitosan, as the N-deacetylated form of chitin, can be employed as a primary material for different industries. The low mechanical stability and poor plasticity of chitosan films, as a result of incompatible interaction between chitosan and the used solvent, have limited its industrialization. Deep eutectic solvents (DESs), as novel solvents, can solve the extraction difficulties of chitin, and the low mechanical stability and weak plasticity of chitosan films. Also, DESs can be considered for the different chitosan and chitin productions, including chitin nanocrystal and nanofiber, N,N,N-trimethyl-chitosan, chitosan-based imprinted structures, and DES-chitosan-based beads and monoliths. This review aims to focus on the preparation and characterization (chemistry and morphology) of DES-chitin-based and DES-chitosan-based structures to understand the influence of the incorporation of DESs into the chitin and chitosan structure.

  • Chitosan-based inks for 3D printing and bioprinting
    • Mohsen Taghizadeh
    • Ali Taghizadeh
    • Mohsen Khodadadi Yazdi
    • Payam Zarrintaj
    • Florian J. Stadler
    • Joshua D. Ramsey
    • Sajjad Habibzadeh
    • Ghasem Naderi
    • Mohammad Saeb
    • Masoud Mozafari
    • Ulrich Schubert
    2022 GREEN CHEMISTRY

    The advent of 3D-printing/additive manufacturing in biomedical engineering field has introduced great potential for the preparation of 3D structures that can mimic native tissues. This technology has accelerated the progress in numerous areas of regenerative medicine, especially led to a big wave of biomimetic functional scaffold developments for tissue engineering demands. In recent years, the introduction of smart bio-inks has created growing efforts to facilitate the preparation of complex and homogeneous living-cell-containing 3D constructs. In the past decade, a considerable body of literature has been created on identifying an ideal bioinspired-ink with excellent printability, cell viability, bioactivity, and mechanical properties. This state-of-the-art review article briefly outlines 3D-printing/bioprinting techniques applied for chitosan-based bio-inks, their resources, crosslinking methods, characteristics, reasons for their superiority over other bio-inks, and challenges of commercialization; this is followed by a comprehensive description of the full potential and the key indicators of success in terms of 3D bio-printing of such bio-inks as platforms for tissue regeneration, advanced biosensors, drug delivery, and wastewater treatment. Next, the restrictions and challenges of chitosan bio-inks are highlighted. In this work, we also discussed about developing a coherent research strategy based on combination of microfluidics-based lab-on-a-chip (organ-on-a-chip) platforms with 3D-bioprinting which enables designing of self-healing scaffolds. And finally, the potential of smart inks based on chitosan for 4D bioprinting of more detailed and practical engineered tissues and artificial organs is reviewed.

  • Chitosan/poly(4-vinylpyridine) coatings formed on AgNPs-decorated titanium
    • Łukasz Pawłowski
    • Michał Bartmański
    • Aleksandra Mielewczyk-Gryń
    • Andrzej Zieliński
    2022 Pełny tekst MATERIALS LETTERS

    Electrophoretic deposition (EPD) of chitosan/poly(4-vinylpyridine) (chit/P4VP) coatings on titanium substrates previously decorated with silver nanoparticles (AgNPs) was performed at different content of P4VP in the suspension and different voltage values. The results revealed that the composite coatings were formed, well-adjacent to the titanium substrate, of suitable roughness, hydrophilicity, and corrosion resistance. The voltage value and P4VP content had complex effects on coating properties, due to the effects of process parameters on microstructure and adhesion. The best coatings of both chitosan and P4VP were formed at 10 V at 0.1% (w/w) during a one-minute deposition. These pH-sensitive antibacterial coatings may, based on the present results, be recommended for surface modification of titanium implants.

  • Chlorine-free extraction and structural characterization of cellulose nanofibers from waste husk of millet (Pennisetum glaucum)
    • C.d. Midhun Dominic
    • Vandita Raj
    • K.v. Neenu
    • P.M. Sabura Begum
    • Krzysztof Formela
    • Mohammad Saeb
    • Deepak D. Prabhu
    • P. Poornima Vijayan
    • T.g. Ajithkumar
    • Jyotishkumar Parameswaranpillai
    2022 INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES

    This study aims to extract cellulose nanofibers (CNFs) from a sustainable source, i.e. millet husk, which is an agro-waste worthy of consideration. Pre-treatments such as mercerisation, steam explosion, and peroxide bleaching (chlorine-free) were applied for the removal of non-cellulosic components. The bleached millet husk pulp was subjected to acid hydrolysis (5% oxalic acid) followed by homogenization to extract CNFs. The extracted CNFs were characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Dynamic Light Scattering (DLS), Energy Dispersive X-ray Spectroscopy (EDX), Thermogravimetry (TG and DTG), Differential scanning calorimetry (DSC), and Solid state 13C nuclear magnetic resonance spectroscopy (solid state 13C NMR). The isolated CNFs show a typical cellulose type-I structure with a diameter of 10-12 nm and a crystallinity index of 58.5%. The appearance of the specific peak at 89.31 ppm in the solid state 13C NMR spectra validates the existence of the type-I cellulose phase in the prepared CNFs. The prepared CNFs had a maximum degradation temperature (Tmax) of 341 °C, that was 31 °C greater than raw millet husk (RMH). The outcome of the study implies that the nanofibers are prominent alternatives for synthetic fibers for assorted potential applications, especially in manufacturing green composites.

  • Choosing the Right Cybersecurity Solution: A Review of Selection and Evaluation Criteria
    • Rafał Leszczyna
    2022 Pełny tekst

    Information technologies evolve continuously reaching pioneering areas that bring in new cybersecurity challenges. Security engineering needs to keep pace with the advancing cyberthreats by providing innovative solutions. At the same time, the foundations that include security and risk assessment methodologies should remain stable. Experts are offered with an extensive portfolio of solutions and an informed choice of a particular one becomes problematic. Transparent criteria are the instrument that answers this issue by laying the ground for evidence-based justifications. Within the framework of systematic literature analysis, this study reviews the criteria proposed in the relevant literature. Based on the outcome, a consolidated set of criteria that should help in choosing a cybersecurity solution is proposed. Ethical questions posed by certain cybersecurity assessment activities are discussed. Consequently, new criteria related to the ethical application of a solution are introduced in the consolidated set.

  • Clean energy in the European Union: Transition or evolution?
    • Radosław Ślosarski
    2022 Pełny tekst Energy & Environment

    In this paper, we analyse two phenomena. First, the relationship between greenhouse gases emission and effectiveness of the European Union energy policies and second the transition from the fossil fuels to renewable energy sources. We run two-step data analysis concerning 25 European Union member states in the period from 1990 to 2018. We use information on greenhouse gases emission, introduction of new energy policies, source of energy supplied and merge it with macroeconomic data on the countries’ structural characteristics. We assess their long-run relationship and direction of causality using panel cointegration tests and dynamic panel data models. We identify a statistically significant effect of energy supply source, energy policy introduction and greenhouse gases emission. However, we were not able to confirm that European Union energy sector is in transition. Thus, obtained results confirm that the EU energy policies are effective however not sufficient enough in decreasing use of fossil fuels to call it a transition towards renewables.

  • Cleaner energy for sustainable future using hybrid photovoltaics-thermoelectric generators system under non-static conditions using machine learning based control technique
    • Adeel Mirza
    • Paweł Szczepankowski
    • Jarosław Łuszcz
    2022 Sustainable Energy Technologies and Assessments

    In addition to the load demand, the temperature difference between the hot and cold sides of the thermoelectric generator (TEG) module determines the output power for thermoelectric generator systems. Maximum power point tracking (MPPT) control is needed to track the optimal global power point as operating conditions change. The growing use of electricity and the decline in the use of fossil fuels have sparked interest in photovoltaic-TEG system utilization in the energy sector. Thermoelectric generation systems are meant to recover waste heat as a green energy supply. Concentrated solar can overcome the drawbacks of inefficient power generation. The feasibility of employing a machine learning and metaheuristic-based control strategy to yield maximum power from a hybrid photovoltaic and thermoelectric generator system under various operating situations is examined in this study. The output of both TEG and PV modules is affected by the environment; PV panels create heat as a result of shade and wind speed. Maximum energy harvesting of PV-TEG under non-uniform temperature settings is proposed in this paper using a feed-forward neural network (FFNN) trained by a squirrel search optimization (SQS). TEG systems have several local maxima due to this non-uniform state. MPPT algorithms based on gradients are unlikely to discover actual GMPP in the majority of cases. The unique SQSFFNN is evaluated under non-uniform temperature distribution and variable load and temperature circumstances as a possible answer to this non-linear issue. Certain advances are made in this study by addressing concerns of global maximum power point tracking with non-uniform temperature distribution, low efficiency, higher settling and tracking time, and oscillations. Particle swarm optimization, Cuckoo search optimization (CSA), CSA-FFNN, and grey wolf optimization algorithms are compared to the outcomes. Four experiments are carried out under various meteorological situations. Experiments and MATLAB/SIMULINK are used to validate and prove the results. The experimental results, comparisons with existing techniques, and statistical data show that the suggested SQDFFNN technique achieves a greater performance, distinguishing PV-TEG as a cleaner source of electrical power generation.

  • Clickable polysaccharides for biomedical applications: A comprehensive review
    • Mohsen Khodadadi Yazdi
    • S. Mohammad Sajadi
    • Farzad Seidi
    • Navid Rabiee
    • Yousef Fatahi
    • Mohammad Rabiee
    • C.D. Midhun Dominic
    • Payam Zarrintaj
    • Krzysztof Formela
    • Mohammad Saeb
    • Sidi A. Bencherif
    2022 Pełny tekst PROGRESS IN POLYMER SCIENCE

    Recent advances in materials science and engineering highlight the importance of designing sophisticated biomaterials with well-defined architectures and tunable properties for emerging biomedical applications. Click chemistry, a powerful method allowing specific and controllable bioorthogonal reactions, has revolutionized our ability to make complex molecular structures with a high level of specificity, selectivity, and yield under mild conditions. These features combined with minimal byproduct formation have enabled the design of a wide range of macromolecular architectures from quick and versatile click reactions. Furthermore, copper-free click chemistry has resulted in a change of paradigm, allowing researchers to perform highly selective chemical reactions in biological environments to further understand the structure and function of cells. In living systems, introducing clickable groups into biomolecules such as polysaccharides (PSA) has been explored as a general approach to conduct medicinal chemistry and potentially help solve healthcare needs. De novo biosynthetic pathways for chemical synthesis have also been exploited and optimized to perform PSA-based bioconjugation inside living cells without interfering with their native processes or functions. This strategy obviates the need for laborious and costly chemical reactions which normally require extensive and time-consuming purification steps. Using these approaches, various PSA-based macromolecules have been manufactured as building blocks for the design of novel biomaterials. Clickable PSA provide a powerful and versatile toolbox for biomaterials scientists and will increasingly play a crucial role in the biomedical field. Specifically, bioclick reactions with PSA have been leveraged for the design of advanced drug delivery systems and minimally invasive injectable hydrogels. In this review article, we have outlined the key aspects and breadth of PSA-derived bioclick reactions as a powerful and versatile toolbox to design advanced polymeric biomaterials for biomedical applications such as molecular imaging, drug delivery, and tissue engineering. Additionally, we have also discussed the past achievements, present developments, and recent trends of clickable PSA-based biomaterials such as three dimensional printing, as well as their challenges, clinical translatability, and future perspectives.

  • Clinical anatomy of the spatial structure of the right ventricular outflow trac
    • Agata Kaczyńska
    • Adam Kosiński
    • Katarzyna Bobkowska
    • Miłosz Zajączkowski
    • Rafał Kamiński
    • Grzegorz Piwko
    • Marta Gleinert-Rożek
    • Tomasz Gos
    • Karol Karnecki
    • Dariusz Kozłowski
    2022 Pełny tekst Advances in Clinical and Experimental Medicine

    Background. The right ventricular outflow tract (RVOT) is located above the supraventricular crest and reaches the level of the pulmonary valve. Detailed knowledge of the RVOT spatial structure and its morphology is extremely important for cardiac invasive therapeutic procedures. Objectives. To examine the spatial structure of the RVOT using virtual models of the right ventricle (RV) interior obtained post mortem. Material and Methods. The study was carried out using 40 adult hearts from both sexes fixed in formalin. Donors had a negative history of cardiovascular diseases. Silicone models of the interior of the RV were made and then subjected to a digital modelling procedure using the photogrammetry technique. For each 3D model of the RV, the RVOT was extracted and measurements were performed. Results. Statistical analysis demonstrated that the dimensions of the transverse (p < 0.001) and sagittal (p = 0.002) axis at the level of the upper and lower border of the RVOT differed significantly. There was also a significant difference between the right and left height of the RVOT (p = 0.009). A clear correlation was found between the volume of the RVOT and the volume of the entire RV (r = 0.718, p < 0.001). Conclusion. The obtained 3D models of the RVOT can help standardize the data related to RVOT architecture. Furthermore, they can extend knowledge about the RVOT in the field of cardiology and improve the procedures in cardiac surgery.

  • Clinical studies of detecting COVID-19 from exhaled breath with electronic nose
    • Andrzej Kwiatkowski
    • Sebastian Borys
    • Katarzyna Sikorska
    • Katarzyna Drozdowska
    • Janusz Smulko
    2022 Pełny tekst Scientific Reports

    The COVID‑19 pandemic has attracted numerous research studies because of its impact on society and the economy. The pandemic has led to progress in the development of diagnostic methods, utilizing the polymerase chain reaction (PCR) as the gold standard for coronavirus SARS‑CoV‑2 detection. Numerous tests can be used at home within 15 min or so but of with lower accuracy than PCR. There is still a need for point‑of‑care tests available for mass daily screening of large crowds in airports, schools, and stadiums. The same problem exists with fast and continuous monitoring of patients during their medical treatment. The rapid methods can use exhaled breath analysis which is non‑invasive and delivers the result quite fast. Electronic nose can detect a cocktail of volatile organic com‑pounds (VOCs) induced by virus infection and disturbed metabolism in the human body. In our exploratory studies, we present the results of COVID‑19 detection in a local hospital by applying the developed electronic setup utilising commercial VOC gas sensors. We consider the technical problems noticed during the reported studies and affecting the detection results. We believe that our studies help to advance the proposed technique to limit the spread of COVID‑19 and similar viral infections.

  • Cluster organization as a form of non-technological innovation
    • Anna Lis
    • Arkadiusz Michał Kowalski
    2022

    The paper aims to investigate the relationships that cluster enterprises develop with their environment through participation in cluster organization (CO). The authors report the findings from a qualitative study carried out in the Lubusz Metal Cluster. The main research strategy is case study. An in-depth individual interview was used to collect the data, and qualitative content analysis and coding for its analysis. The study has shown that cluster enterprises develop relationships with various groups of stakeholders, which include other enterprises, R&D institutions, educational institutions, business environment institutions, and public authorities. Building relationships with each of these groups of stakeholders is based on different set of goals; it also leads to obtaining a different pool of value creating benefits, which are jointly formed by all groups of stakeholders. The first-order benefits result directly from the cluster cooperation, while the second-order benefits consist in gradual integration: first in the social dimension, then in the process and organizational dimension, and ending with the integration of the entire industry. The research goes beyond the state-of-the-art knowledge in the concept of industrial clusters, revealing CO as an example of non-technological innovation, which applies in particular management of external relations with other companies or public institutions.

  • Cmentarze w przestrzeni polskich miast
    • Anna Myślińska
    2022 Pełny tekst

    Przedmiotem badań jest przedstawienie cmentarzy na terenach polskich miast: Gdańska, Krakowa, Lublina, Warszawy i Wrocławia. Na potrzeby pracy przeanalizowano położenie cmentarzy względem współczesnej i historycznej tkanki miejskiej a także względem innych nekropolii, dzięki czemu zidentyfikowano zjawisko występowania zespołów cmentarzy miejskich. Zbadano także zagadnienie likwidacji cmentarzy miejskich i odniesiono je do współczesnych problemów związanych z wpływem nekropolii na środowisko. Wyczerpujący opis wymienionych wyżej zagadnień powstał w oparciu o literaturę tematu, badania źródeł kartograficznych oraz studia obejmujące: historię cmentarzy w wybranych miastach, zestawienie zarówno istniejących jak i nieistniejących cmentarzy we współczesnych granicach administracyjnych tych miast oraz analizę współczesnych funkcji terenów na obszarach nieistniejących już nekropolii. Zebraną wiedzę wykorzystano w celu stworzenia wytycznych dla projektowania nowoczesnych nekropolii miejskich.

  • c-Myc Protein Level Affected by Unsymmetrical Bisacridines Influences Apoptosis and Senescence Induced in HCT116 Colorectal and H460 Lung Cancer Cells
    • Monika Pawłowska
    • Jolanta Kulesza
    • Ewa Augustin
    2022 Pełny tekst INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    Unsymmetrical bisacridines (UAs) are highly active antitumor compounds. They contain in their structure the drugs previously synthesized in our Department: C-1311 and C-1748. UAs exhibit different properties than their monomer components. They do not intercalate to dsDNA but stabilize the G-quadruplex structures, particularly those of the MYC and KRAS genes. Since MYC and KRAS are often mutated and constitutively expressed in cancer cells, they can be used as therapeutic targets. Herein, we investigate whether UAs can affect the expression and protein level of c-Myc and K-Ras in HCT116 and H460 cancer cells, and if so, what are the consequences for the UAs-induced cellular response. UAs did not affect K-Ras, but they strongly influenced the expression and translation of the c-Myc protein, and in H460 cells, they caused its full inhibition. UAs treatment resulted in apoptosis, as confirmed by the morphological changes, the presence of sub-G1 population and active caspase-3, cleaved PARP, annexin-V/PI staining and a decrease in mitochondrial potential. Importantly, apoptosis was induced earlier and to a greater extent in H460 compared to HCT116 cells. Moreover, accelerated senescence occurred only in H460 cells. In conclusion, the strong inhibition of c-Myc by UAs in H460 cells may participate in the final cellular response (apoptosis, senescence).

  • Co stymuluje rozwój współczesnej teleinformatyki i jakie są istotne kierunki tego rozwoju?
    • Józef Woźniak
    • Jordi Mongay Batalla
    • Andrzej Bęben
    • Marek Natkaniec
    • Zbigniew Piotrowski
    • Krzysztof Szczypiorski
    2022 Pełny tekst Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

    Corocznie dokonuje się oceny stanu sztuki i tendencji w rozwoju światowej telekomunikacji i (tele)informatyki przywołując „mierzalne” i „niemierzalne” zmiany. W artykule przedstawiono charakter tych zmian oraz wskazano wyzwania badawcze i wdrożeniowe istotne dla rozwoju tych dyscyplin. Zaprezentowano i scharakteryzowano ewolucję infrastruktury sieciowej prowadzącą do sieci programowalnych SDN (Software Defined Network) oraz wykorzystania technik wirtualizacji funkcji sieciowych NFV (Network Function Virtualisation), prezentując też kierunki rozwoju nowych aplikacji i usług oferowanych z wykorzystaniem zasobów chmur obliczeniowych oraz technik przetwarzania danych na brzegu sieci (Edge/Fog computing). Szczególną uwagę poświęcono systemom i sieciom piątej generacji 5G, adresującym problemy różnych grup użytkowników i odpowiadającym na bardzo zróżnicowane wymagania jakościowe, energetyczne czy zasięgowe. Zaprezentowano też podstawowe obszary zastosowań Internetu Rzeczy oraz Wszechrzeczy IoT/IoE, prezentując w tym kontekście potrzeby i korzyści związane z użyciem technik uczenia maszynowego oraz sztucznej inteligencji do zapewniania efektywniejszego wykorzystania zasobów sieci IoT, czy też istotnego komponentu sieci 5G jakim jest Przemysł 4.0. Dokonano też krótkiej analizy zagrożeń oraz zasad wdrażania cyberbezpieczeństwa i zapewniania bezpieczeństwa informacji w systemach i sieciach teleinformatycznych. SŁOWA KLUCZOWE: Technologie ICT, trendy w rozwoju, kierunki zmian, charakterystyka, separacja oprogramowania i sprzętu: VFN, SDN, sieci 5G, IoT/E, aplikacje chmurowe, obliczenia na brzegu sieci: Edge/Fog computing, cyberbezpieczeństwo: zagrożenia i metody przeciwdziałania

  • Cognitive neuroscience: Theta network oscillations coordinate development of episodic memory
    • Michał Kucewicz
    2022 Pełny tekst CURRENT BIOLOGY

    Our ability to remember life events matures through childhood and adolescence. A new study has revealed how theta oscillations between two anatomical brain regions supporting memory and executive functions are synchronized and develop across age through functional and structural connectivity.

  • Cold recycled mixtures for binder courses - laboratory evaluation of mechanical properties
    • Bohdan Dołżycki
    • Mariusz Jaczewski
    • Cezary Szydłowski
    2022 Pełny tekst

    Cold recycled mixtures composed with cement and bituminous emulsion are nowadays commonly used material for base layer. Typical pavement with cold recycled mixtures usually consists of two asphalt courses (wearing and binding course) constructed over cold recycled base. Therefore the next step in cold recycling is possibility of design of binding courses with recycled materials, but with potential to obtain high quality mixtures similar to commonly used asphalt concretes. In this case, typical new pavement structure would be designed as two cold recycled mixtures (for base and binding course) covered by wearing course. This publication presents both basic and advanced laboratory results for cold recycled binding course. Cold recycle binding course is characterized by more strict requirements for base material gradation and more strict ranges for possible properties. Also the composition of binding agents is selected to be as similar as for typical asphalt concretes. In laboratory following test were performed: volumetric properties, resistance to water and frost action, viscoelastic properties (dynamic modulus, phase angles) and resistance to fracture in SCB test. For comparison, the same test were performed for asphalt concrete for binder course and for selected test also for cement bound mixtures. Obtained results indicate that cold recycled mixtures for binder course are located between typical asphalt concretes and cement bound mixtures, characterizing by both high bearing capacity and sufficient viscoelastic properties. In the case of resistance to water and frost, cold recycled mixtures are characterized by ratio between 75-85%. Cold recycled mixtures showed good fracture resistance results in SCB test in comparison to other tested mixtures. Laboratory stage of research confirmed very good properties of cold recycled binding course and open possibility for further steps to construct and evaluate the designed mixtures on real life conditions on trial section in real environmental conditions.

  • Collective creativity in management science
    • Damian Ciachorowski
    • Anna Lis
    2022 Pełny tekst Engineering Management in Production and Services

    Purpose: The purpose of this paper is to establish the current state of knowledge on collective creativity in management science on the basis of a systematic literature review. Methodology: A systematic review was performed based on the three-step SPL procedure proposed by Tranfield et al. (2003). Two databases (Scopus and Web of Science) were searched electronically up until March 2022. Based on the secondary data a literature analysis and content analysis were carried out. Results: As a result of the systematic literature review procedure, a total of eighteen studies met the inclusion criteria. The descriptive and thematic analysis conducted allowed to establish the state of knowledge in the analyzed area and to identify the main thematic areas along with the directions of future research. The theoretical contribution: The proposed research is the first to conduct a systematic literature review in collective creativity in management science. The main contribution of this paper is its exclusive focus on the analysis of existing research in the field of collective creativity, additionally limited to management science. Based on SLR, it was possible to determine that research in the analyzed area is still at a fairly early stage. Although the existing literature sheds some light on collective creativity, studies investigating the great aspects of teamwork focused on problem solving are needed.

  • ColorNephroNet: Kidney tumor malignancy prediction using medical image colorization
    • Aleksander Obuchowski
    • Barbara Klaudel
    • Roman Karski
    • Bartosz Rydziński
    • Mateusz Glembin
    • Paweł Syty
    • Patryk Jasik
    2022 Pełny tekst Proceedings of FLAIRS-35

    Renal tumor malignancy classification is one of the crucial tasks in urology, being a primary factor included in the decision of whether to perform kidney removal surgery (nephrectomy) or not. Currently, tumor malignancy prediction is determined by the radiological diagnosis based on computed tomography (CT) images. However, it is estimated that up to 16% of nephrectomies could have been avoided because the tumor that had been diagnosed as malignant, was found to be benign in the postoperative histopathological examination. The excess of false-positive diagnoses results in unnecessarily performed nephrectomies that carry the risk of periprocedural complications. In this paper, we present a machine-aided diagnosis system that predicts the tumor malignancy based on a CT image. The prediction is performed after radiological diagnosis and is used to capture false-positive diagnoses. Our solution is able to achieve a 0.84 F1-score in this task. We also propose a novel approach to knowledge transfer in the medical domain in terms of colorization based pre-processing that is able to increase the F1-score by up to 1.8pp.

  • Combined anticancer therapy with imidazoacridinone analogue C‐1305 and paclitaxel in human lung and colon cancer xenografts—Modulation of tumour angiogenesis
    • Marta Świtalska
    • Beata Filip‐Psurska
    • Magdalena Milczarek
    • Mateusz Psurski
    • Adrianna Moszyńska
    • Aleksandra Dąbrowska
    • Małgorzata Gawrońska
    • Karol Krzymiński
    • Maciej Bagiński
    • Rafał Bartoszewski
    • Joanna Wietrzyk
    2022 Pełny tekst JOURNAL OF CELLULAR AND MOLECULAR MEDICINE

    The acridanone derivative 5-dimethylaminopropylamino- 8- hydroxytriazoloacridinone (C-1305) has been described as a potent inhibitor of cancer cell growth. Its mechanism of action in in vitro conditions was attributed, among others, to its ability to bind and stabilize the microtubule network and subsequently exhibit its tumour- suppressive effects in synergy with paclitaxel (PTX). Therefore, the objective of the present study was to analyse the effects of the combined treatment of C-1305 and PTX in vivo. In addition, considering the results of previous genomic analyses, par-ticular attention was given to the effects of this treatment on tumour angiogenesis. Treatment with C-1305 revealed antitumor effect in A549 lung cancer cells, and com-bined treatment with PTX showed tendency to anticancer activity in HCT116 colon cancer xenografts. It also improved tumour blood perfusion in both tumour models. The plasma level of CCL2 was increased and that of PDGF was decreased after com-bined treatment with C-1305 and PTX. The experimental results showed that the levels of FGF1, TGF-β and Ang-4 decreased, whereas the levels of ERK1/2 and Akt phosphorylation increased in HCT116 tumour tissue following combined treatment with both drugs. The results of in vitro capillary- like structure formation assay dem-onstrated the inhibiting effect of C-1305 on this process. Although previous in vitro and in vivo studies suggested a positive effect of C-1305 on cancer cells, combined treatment of HCT116 human colon and A549 lung cancer cells with both PTX and C- 1305 in vivo showed that the antitumor activity was restricted and associated with the modulation of tumour angiogenesis.

  • Combined chemoresistive and in situ FTIR spectroscopy study of nanoporous NiO films for light-activated nitrogen dioxide and acetone gas sensing
    • Katarzyna Drozdowska
    • Tesfalem Welearegay
    • Lars Österlund
    • Janusz Smulko
    2022 Pełny tekst SENSORS AND ACTUATORS B-CHEMICAL

    The chemoresistive sensor response of nanoporous NiO films prepared by advanced gas deposition was investigated by combined resistivity and in situ FTIR spectroscopy, with and without simultaneous light illumination, to detect NO2 and acetone gases. The sensitivity towards NO2 increased dramatically under UV irradiation employing 275 nm light. Improved sensitivity was observed at an elevated temperature of 150 °C. In situ FTIR measurements were performed to record the transient gas adsorption/desorption processes. The sustained sensitivity and repeatability for NO2 sensing could be attributed to reversible surface-nitro and nitrate species formation, which are stable on the surface at relative humidity up to 40%. In contrast, acetone sensing results in irreversible decomposition and accumulation of reaction products on the NiO sensor surface, covering the surface and limiting gas sensing. Implications of the study for improved and sustained NiO gas sensor properties in gas mixtures are discussed.

  • Combined cold supply system for ship application based on low GWP refrigerants - Thermo-economic and ecological analyses
    • Jan Wajs
    • Michał Mrózek
    • Elzbieta Fornalik-Wajs
    2022 Pełny tekst ENERGY CONVERSION AND MANAGEMENT

    The withdrawal of popular high-GWP refrigerants will significantly affect maritime industry. Refrigeration and air conditioning systems currently used on ships are not ready to fulfil future limitations. Therefore, there is a need for system, which will operate with low-GWP refrigerants and at the same time will be efficient and reliable in difficult environmental conditions. This paper explains the concept of a cold supply system, in which refrigeration/freezing plant rejects heat not to a seawater but to a chilled water, produced by the air conditioning unit. Configuration of single stage compression with internal heat exchanger and HFO refrigerant was used in the air conditioning system, while in the refrigeration/freezing plant, two-stage compression trans-critical booster with R744 as refrigerant. Comparative thermodynamic analyses of presented concept with other configurations of thermodynamic cycles and refrigerants were performed. They were carried out in wide range of seawater temperature values and incorporated efficiency characteristics of compressors produced by a well-known manufacturers. Results confirmed ability of described system to improve energy efficiency in comparison with separated and currently used on ships cold supply systems, especially in hot climate. Economic and ecological analyses of proposed concept exhibited an additional benefit - positive environmental impact.

  • Combined numerical and experimental approach to determine numerical model of abdominal scaffold
    • Agnieszka Tomaszewska
    • Daniil Reznikov
    2022 Pełny tekst COMPUTER METHODS IN BIOMECHANICS AND BIOMEDICAL ENGINEERING

    A proper junction of the prosthesis and the abdominal wall is important in successful hernia repair. The number of tacks should be balanced to assure appropriate mesh fixation and not to induce post-operative pain. Numerical simulations help to find this balance. The study is aimed at creating a proper numerical model of a knitted surgical mesh subjected to boundary conditions and load occurring in the abdominal cavity. Continuous, anisotropic constitutive relation is considered to reflect the mesh behaviour. Different sets of material law parameters are determined on the basis of different bi-axial tests setups. Force- and displacement-controlled tests with different ratios are considered. Consequently, some numerical model variants are obtained featuring various reaction distributions in the scaffold fixation points. The proper variant is selected based on comparison of the position of maximal reaction force in the numerical model and in the reference physical model of operated hernia. Force-driven tests have shown anisotropic mesh behaviour, while equibiaxial displacement-driven test has demonstrated reduced anisotropic response. Within seven scenarios of constitutive parameters identification (based on single or combined experimental data), the equibiaxial force-controlled test appeared to produce the most relevant model to follow the prosthesis behaviour under pressure. The position of maximal reaction force in such model is similar to obtained in the physical hernia model. The equibiaxial force-driven test provides most suitable data for Gasser-Ogden-Holzapfel constitutive model identification of a considered surgical mesh to be used to model the mesh under pressure

  • Combined partial denitrification/anammox process for nitrogen removal in wastewater treatment
    • Hussein Al-Hazmi
    • Dominika Derwis
    • Joanna Majtacz
    • Aleksandra Ziembińska-Buczyńska
    • Jun Zhai
    • Jacek Mąkinia
    2022 Journal of Environmental Chemical Engineering

    Recently, the combined partial denitrification and anammox (PD/anammox) has received special attention as a viable alternative for N removal using organic matter present in municipal wastewater. In comparison with conventional nitrification-denitrification, PD/anammox provides enormous opportunities to achieve sustainable wastewater treatment due to the lack of dissolved oxygen (DO) demand, a smaller amount of organic carbon (C) and less excess sludge production and GHG emissions. The PD/anammox process can be widely carried out in different technical systems, including single- or two-stage systems for side-stream and mainstream wastewater. This review focuses on the latest improvements related to the PD/anammox system and discusses the production/consumption pathways of NO2- as a critical intermediate. The C/N ratio plays a key role in the PD/anammox process; therefore, the concentration of the dosed organic C is important due to its negative influence on the activity of anammox resulting from the overgrowth of denitrifying bacteria in the systems. Understanding microorganism competition in a one-stage PD/anammox is typically the most important key to optimal efficiency of N removal from mainstream wastewater. Therefore, in this review, a comprehensive description of microbial metabolism i.e., autotrophic anammox, denitrifying heterotrophs/autotrophs, DNRA heterotrophs, and the contiguity competition between them in single-stage PD/anammox systems are inclusively explained. The challenge and limitations are described to recognize inhibition mechanisms and performance inhibitors. The combination of PD/anammox with other processes and the development of a self-supporting bacterial system should be the main lines of future research and efficiency development towards further enhancing total nitrogen removal efficiency (TNRE).

  • COMMON FIRE CAUSES IN INDUSTRIAL SITES
    • Mehmet Gökçü
    • Mariusz Jaczewski
    2022

    Chapter presents common causes of fires in industrial places

  • Communication as a Factor Limiting University-Business Cooperation
    • Sylwia Sieracka
    • Marek Wirkus
    2022 GATR Global Journal of Business and Social Science Review

    Objective - Despite the broad extent of the scientific activity dealing with university-business cooperation, Poland has yet to develop a satisfactory cooperation strategy that takes business needs into account. This issue is still relevant due to the need for continuous improvement and resulting benefits aimed at improving enterprise competitiveness. Methodology/Technique - Authors of this article attempt to select an overriding determinant that has an impact on maintaining the balance of cooperation between businesses and universities, constituting the basis for further research on the creation of a cooperation strategy. Finding - Based on the conducted pilot studies, the authors propose the implementation of marketing orientation towards business-university relations, influencing the improvement of communication and selective drawing of ideas from the experiences of other countries. Novelty - The proposed solutions aim to initiate further activities to build global cooperation networks using artificial intelligence tools, i.e. a broker platform. Keywords: Communication, business, university, cooperation, marketing orientation

  • Compact and Integrated High-Power Pulse Generation and Forming System
    • Mikołaj Nowak
    • Kazimierz Jakubiuk
    • Daniel Kowalak
    • Marek Pikoń
    • Józef Czucha
    • Piotr Jankowski
    2022 Pełny tekst ENERGIES

    This paper presents comprehensive analytical, numerical and experimental research of the compact and integrated high-power pulse generation and forming system based on the flux compression generator and the electro-explosive forming fuse. The paper includes the analysis of the presented solution, starting from the individual components studies, i.e., the separate flux compression generator tests in field conditions and the forming fuse laboratory test, through the formulation of the extended quasi-empirical components models aimed at enabling their optimal parameters determination at the early design stage and ending with the description of the integrated system studies in field conditions. Based on detailed research, it was possible to achieve very high parameters of the generated pulses, i.e., overvoltages of up to 340 kV with the available source power reaching 25 GW. A very high convergence of the simulation and the results of experimental research has been obtained. The parameters of the presented system have been compared with other literature solutions and the selected topology of the high power pulse generation and forming system has been distinguished against other available ones, e.g., based on Marx generators and forming lines.

  • Compact Electromagnetic Lens Antennas Using Cascaded Metasurfaces for Gain Enhancement and Beam Steering Applications
    • Rao Aziz
    • Amit Singh
    • Jun-Sung Park
    • Seong-Ook Park
    • Sławomir Kozieł
    2022 INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING

    Electromagnetic (EM) lens antenna designs using cascaded metasurfaces for gain enhancement and beam steering applications are proposed. Two different lens aperture designs are proposed and populated with aperiodic unit cells of size 0.2λo × 0.2λo. In lens Design 1, the unit cells of different phases are distributed in concentric circular zones, whereas in lens Design 2, the unit cells of different phases are distributed in vertical linear zones on the aperture of the EM lens. Both lenses are composed of two cascaded metasurfaces with an air gap of 0.047λo (where λo = 51.7 mm at 5.8 GHz). For gain enhancement, the metasurfaces are positioned at an optimum focal distance, f = 0.61λo above source patch antenna (f/D = 0.3). Beam steering is accomplished by phase transformation of the source antenna, which can be realized by mechanically sliding the passive metasurfaces in one direction (i.e., ±x-direction) above the source antenna. The prototype of the two proposed lenses are fabricated and tested. The measured peak boresight gain obtained from Design 1 and 2 are 14.98 dBi and 15.12 dBi, respectively. The experimental results show -25o to +25o and -27o to +27o beam steering range for Design 1 and 2, respectively, with a little gain degradation at other angles.

  • Compact High Efficiency and Zero-Emission Gas-Fired Power Plant with Oxy-Combustion and Carbon Capture
    • Paweł Ziółkowski
    • Stanisław Głuch
    • Piotr Józef Ziółkowski
    • Janusz Badur
    2022 Pełny tekst ENERGIES

    Reduction of greenhouse gases emissions is a key challenge for the power generation industry, requiring the implementation of new designs and methods of electricity generation. This article presents a design solution for a novel thermodynamic cycle with two new devices—namely, a wet combustion chamber and a spray-ejector condenser. In the proposed cycle, high temperature occurs in the combustion chamber because of fuel combustion by pure oxygen. As a consequence of the chemical reaction and open water cooling, a mixture of H2O and CO2 is produced. The resulting working medium expands in one turbine that combines the advantages of gas turbines (high turbine inlet temperatures) and steam turbines (full expansion to vacuum). Moreover, the main purpose of the spray-ejector condenser is the simultaneous condensation of water vapour and compression of CO2 from condensing pressure to about 1 bar. The efficiency of the proposed cycle has been estimated at 37.78%. COM-GAS software has been used for computational flow mechanics simulations. The calculation considers the drop in efficiency due to air separation unit, carbon capture, and spray-ejector condenser processes. The advantage of the proposed cycle is its compactness that can be achieved by replacing the largest equipment in the steam unit. The authors make reference to a steam generator, a conventional steam condenser, and the steam-gas turbine. Instead of classical heat exchanger equipment, the authors propose non-standard devices, such as a wet combustion chamber and spray-ejector condenser.

  • Compact, Order Extensible and Wide-Stopband Bandpass Filter Based on SIW Cavity with Rectangular Ring Slot
    • Rusan Kumar Barik
    • Sławomir Kozieł
    2022 IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-EXPRESS BRIEFS

    This article introduces novel architectures of bandpass filters (BPFs) using a substrate integrated waveguide (SIW) cavity with a rectangular ring slot (RRS) for compact size, extensible order, and broad stopband responses. Two bandpass filters, which demonstrate a second-and a fourth-order Chebyshev response, respectively, are realized by employing identical cavities with RRS, without increasing the physical size of the circuit. A rectangular ring slot is etched along the perimeter and a metallic via is allocated towards the bottom edge of the cavity to realize the resonances. The resonant frequencies of different modes are controlled by introducing one or three slots, which enable the realization of the second and fourth-order BPFs with wide stopbands, respectively. The working principles of the filters are illustrated by applying the eigen-mode analysis, field distribution, and the coupling matrix. Finally, a second-order BPF centered at 0.87 GHz, and a fourth-order BPF centered at 0.92 GHz are synthesized, fabricated, and experimentally validated. As compared to the earlier works, the proposed fourth-order BPF offers competitive performance with a low insertion-loss of 0.7 dB, compact size of 0.036λ2, and a wide passband of 22.1%. Additionally, the second- and the fourth-order BPFs achieve wide upper stopband responses of 3.86f0 at a level greater than 20dB and 3.98f0 at a level greater than 30dB, respectively.

  • Comparable analysis of PID controller settings in order to ensure reliable operation of active foil bearings
    • Łukasz Witanowski
    • Łukasz Breńkacz
    • Natalia Szewczuk-Krypa
    • Marta Drosińska-Komor
    • Bartosz Puchalski
    2022 Pełny tekst Eksploatacja i Niezawodność - Maintenance and Reliability

    In comparison to the traditional solutions, active bearings offer great operating flexibility, ensure better operating conditions over a wider range of rotational speeds and are safe to use. In order to ensure optimum bearing performance a bearing control system is used that adapts different geometries during device operation. The selection of optimal controller parameters requires the use of modern optimization methods that make it possible to quickly achieve the assumed parameters. This article presents the method that has been employed to select the parameters of a proportional integral derivative (PID) controller, in which both stochastic algorithms and hybrid methods have been compared. The results show that all of the used algorithms were able to reach the global optimum but only the hybrid algorithm was repeatable in all runs within a low value of the standard deviation. The best solution will be proposed in the future to control an active foil bearing. Analysing of this paper would help to prevent failures of active foil bearing used in the designed rotating machine.

  • Comparative Analysis of Developed Rainfall Intensity–Duration–Frequency Curves for Erbil with Other Iraqi Urban Areas
    • Dalshad Ahmed Kareem
    • Aumed Rahman M Amen
    • Andam Mustafa
    • Mehmet Ishak Yüce
    • Michał Szydłowski
    2022 Pełny tekst Water

    Rainfall Intensity–Duration–Frequency (IDF) relationships are widely used in water infrastructure design and construction. IDF curves represent the relationship between rainfall intensity, duration, and frequency, and are obtained by analyzing observed data. These relationships are critical for the safe design of flood protection structures, storm sewers, culverts, bridges, etc. In this study, the IDF curves and empirical IDF formulas for the city of Erbil were developed for the first time by employing the annual maximum rainfall data for a period of 39 years (1980–2018), which is the only available recorded data. Statistical techniques such as Gumbel and Log-Pearson Type III (LPT III) were utilized to determine the IDF curves and empirical equations from daily rainfall data for several standard durations and return periods. The correlation between the rainfall intensities obtained from IDF curves and the empirical formula presented a reliable match, with a coefficient of determination of (R2 = 1). The results were compared to previously developed IDF curves and empirical formulas in Iraqi cities to show their reliability. Moreover, the results can be an initial step for authorities to establish required guidelines in the studied area, and in the design process of the storm water infrastructure of urban basins in the future.

  • Comparative analysis of mRNA transcripts of HT-29 cell line expressed in identical quantities for pathogenic E. coli strains UM146 and UM147 with control Escherichia coli Nissle 1917
    • Roman Kotłowski
    2022 Pełny tekst Journal of Genomics

    Aim of study was comparative analysis of mRNA transcripts of HT-29 cell line, expressed in identical quantities for the combination of pathogenic and non-pathogenic Escherichia coli strains. HT-29 confluent monolayers infection with two pathogenic E. coli strains UM146 and UM147 resulted in two sets of mRNA transcripts that were identical with RNA transcripts obtained for non-pathogenic one strain E. coli Nissle 1917. In this study genome-wide experiments were conducted using expression microarray-system. Only one common mRNA transcript coding for CCDC65 gene was equally expressed by HT-29 cells after incubation challenge with three different E. coli strains used. This gene and its bacterial analogue are important in the ciliary or flagellar motility, respectively. Altogether, 78 and 81 HT-29 mRNA transcripts for E. coli UM146 and E. coli UM147 had identical RNA quantity in comparison to the response obtained for non-pathogenic E. coli Nissle 1917 interactions with HT-29 monolayers. Specific analysis using REACTOME and agriGO terms enrichment data-mining tools as well as word-cloud analysis allowed for identification the most important processes characteristic during HT-29 cell line infections for each pathogenic E. coli strain used. The importance of results may contribute to recognition of those processes during bacterial infections that are identical with processes arising from human interaction with non-pathogenic strains that belong to the same bacterial species.

  • Comparative Analysis of Reactive Power Compensation Devices in a Real Electric Substation
    • Hanan Tariq
    • Stanislaw Czapp
    • Sarmad Tariq
    • Khalid Mehmood Cheema
    • Aqarib Hussain
    • Ahmad H. Milyani
    • Sultan Alghamdi
    • Z. M. Salem Elbarbary
    2022 Pełny tekst ENERGIES

    A constant worldwide growing load stress over a power system compelled the practice of a reactive power injection to ensure an efficient power network. For this purpose, multiple technologies exist in the knowledge market out of which this paper emphasizes the usage of the flexible alternating current transmission system (FACTS) and presents a comparative study of the static var compensator (SVC) with the static synchronous compensator (STATCOM), inducted in a real electric substation. The aim is to improve the power factor (PF) and power quality and to encounter reliably extreme conditions. A 220 kV electric substation was opted for the analysis, and both the static and dynamic conditions were observed with the help of a power system analysis tool termed PowerFactory-DIgSILENT. Multiple aspects were investigated via software simulations to assess the performance of the aforementioned FACTS devices, such as the voltage profile evaluation via the load flow analysis method (LFA), the harmonic response via the power quality and harmonic analysis tool, and the short-circuit response via the RMS simulation tool. The outcomes were verified and compared with permissible values included in the universal standards, such as IEC and IEEE. The superiority of the STATCOM over the SVC was proven in light of the simulative results.

  • Comparative analysis of the flow control over a circular cylinder with detached flexible and rigid splitter plates
    • Faezeh Eydi
    • Afsaneh Mojra
    • Rezvan Abdi
    2022 Pełny tekst PHYSICS OF FLUIDS

    A comparative study is performed on a circular cylinder with both flexible and rigid splitter plates (SPs). This study has the novelty of using single and dual detached SPs located downstream of the cylinder. The dimensionless gap distance between the first splitter plate and the cylinder as well as the distance between the SPs are varied. The strain of flexible SPs can be used for energy harvesting from the flow. Therefore, a parametric study is performed to find the optimal design for placing piezoelectric polymers. The two-dimensional fluid–structure-interaction analysis is performed based on the arbitrary Lagrangian–Eulerian scheme using COMSOL Multiphysics. Flow characteristics quantities, tip amplitude, and strain are evaluated at different arrangements of the SPs. The results reveal that wake control enhances effectively by doubling the number of SPs. Strain assessments indicate that the strain of dual SPs increases by more than 100% compared to the single plate case. In addition, the amplitude of the dual SPs increases by a remarkable ratio of 18.29 compared to the single plate. In the case of rigid and flexible SPs at a certain arrangement, dramatic reductions of 97.8% and 76.35% in the Strouhal number are obtained compared to a bare cylinder. In addition, 18% drag reduction compared to the bare cylinder is recorded for the rigid SPs. The presented passive method can be used as an attractive approach in flow control as well as energy harvesting from ocean waves and sea currents.

  • Comparative Assessment of Bacteriophage and Antibiotic Activity against Multidrug-Resistant Staphylococcus aureus Biofilms
    • Natalia Kaźmierczak
    • Bartłomiej Grygorcewicz
    • Marta Roszak
    • Beata Bochentyn
    • Lidia Piechowicz
    2022 Pełny tekst INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    Problems connected with biofilm-related infections and antibiotic resistance necessitate the investigation and development of novel treatment strategies. Given their unique characteristics, one of the most promising alternatives to conventional antibiotics are bacteriophages. In the in vitro and in vivo larva model study, we demonstrate that phages vB_SauM-A, vB_SauM-C, and vB_SauM-D are effective antibiofilm agents. The exposure of biofilm to phages vB_SauM-A and vB_SauM-D led to 2–3 log reductions in the colony-forming unit number in most of the multidrug-resistant S. aureus strains. It was found that phage application reduced the formed biofilms independently of the used titer. Moreover, the study demonstrated that bacteriophages are more efficient in biofilm biomass removal and reduction in staphylococci count when compared to the antibiotics used. The scanning electron microscopy analysis results are in line with colony forming unit (CFU) counting but not entirely consistent with crystal violet (CV) staining. Additionally, phages vB_SauM-A, vB_SauM-C, and vB_SauM-D can significantly increase the survival rate and extend the survival time of Galleria mellonella larvae.

  • Comparative review of piezoelectric biomaterials approach for bone tissue engineering
    • Ali Samadi
    • Mohammad Amin Salati
    • Amin Safari
    • Maryam Jouyandeh
    • Mahmood Barani
    • Narendra Pal Singh Chauhan
    • Elias Ghaleh Golab
    • Payam Zarrintaj
    • Saptarshi Kar
    • Farzad Seidi
    • Aleksander Hejna
    • Mohammad Saeb
    2022 JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION

    Bone as a minerals’ reservoir and rigid tissue of the body generating red and white blood cells supports various organs. Although the self-regeneration property of bone, it cannot regenerate spontaneously in severe damages and still remains as a challenging issue. Tissue engineering offers several techniques for regenerating damaged bones, where various biomaterials are examined to fabricate scaffolds for bone repair. Piezoelectric characteristic plays a crucial role in repairing and regenerating damaged bone by mimicking the bone niche behavior. Piezoelectric biomaterials show significant potential for bone tissue engineering. Herein we try to have a comparative review on piezoelectric and non-piezoelectric biomaterials used in bone tissue engineering, classified them, and discussed their effects on implanted cells and manufacturing techniques. Especially, Polyvinylidene fluoride (PVDF) and its composites are the most practically used piezoelectric biomaterials for bone regeneration. PVDF and its composites have been summarized and discussed to repair damaged bone tissues.

  • Comparative study of high‑pressure fluid flow in densely packed granules using a 3D CFD model in a continuous medium and a simplified 2D DEM‑CFD approach. Granular Matter
    • Rezvan Abdi
    • Marek Krzaczek
    • Andrzej Tejchman-Konarzewski
    2022 Pełny tekst GRANULAR MATTER

    Izotermiczny ściśliwy jednofazowy przepływ cieczy przez niejednorodną masę ziarnistą składającą się z gęsto upakowanych zachodzących na siebie kul imitujących skałę pod wysokim ciśnieniem zbadano numerycznie przy użyciu dwóch różnych podejść. Pierwsze podejście zwane pełnym modelem 3D CFD stosowało metodę skończonych objętości (FVM) do rozwiązania uśrednionego równania Naviera-Stokesa zakładając model naprężeń Reynoldsa (BSL) w osrodku ciągłym pomiędzy granulatami. Model został zweryfikowany na podstawie wyników doświadczalnych i liczbowych z literatury. Drugim podejściem był uproszczone sprzężone podejście DEM-CFD oparte na tzw. modelu sieci przepływu. Głównym celem pracy było opracowanie procedury walidacji uproszczonych sprzężonych modeli DEM-CFD ze względu na brak danych doswiadczalnych dla charakterystyk przepływu płynu w gęsto upakowanych granulatach w warunkach ekstremalnie wysokiego ciśnienia. Najpierw przeprowadzono serię symulacji numerycznych dla osrodka płynu z pełnym modelem 3D CFD. Wyniki tych symulacji zostały następnie wykorzystane do walidacji wyników numerycznych 2D uproszczonego sprzężonego modelu DEM-CFD w odniesieniu do prędkości, ciśnień, gęstości i szybkości przepływu. W obu podejściach uzyskano prawie takie same rozkłady ciśnienia i gęstości oraz natężenia przepływu masowego. Prędkość płynu była jednak inna ze względu na różne objętości płynu w obu ośrodkach. Wyniki symulacji numerycznych stanowią wiarygodny punkt odniesienia dla walidacji innych połączonych modeli 2D/3D DEM-CFD, które wykorzystują modele sieciowe.

  • Comparison of image pre-processing methods in liver segmentation task
    • Kamil Kaczor
    • Paweł Nadachowski
    • Maksymilian Operlejn
    • Artur Piastowski
    • Marta Zielonka
    • Jan Cychnerski
    • Alicja Kwaśniewska
    2022

    Automatic liver segmentation of Computed Tomography (CT) images is becoming increasingly important. Although there are many publications in this field there is little explanation why certain pre-processing methods were utilised. This paper presents a comparison of the commonly used approach of Hounsfield Units (HU) windowing, histogram equalisation, and a combination of these methods to try to ascertain what are the differences between them and how big the differences are. All experiments were conducted on the LiTS dataset. To achieve comparable and reliable results only one architecture of neural network is used which is U-Net with ResNet34 blocks

  • Comparison of the characteristics of journal bearings determined according to ISO 7902:2020 and obtained by other methods
    • Jan Smykla
    • Michel Fillon
    • Artur Olszewski
    • Tomasz Żochowski
    • Lidia Gałda
    2022 PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY

    The article presents selected characteristics of journal bearings calculated with the use of various methods and compared to the results obtained with application of the basic bearing characteristics calculation procedure, as described in the ISO 7902:2020 standard. Additionally, the presented calculation results were compared with the parameters measured during experimental tests of the sliding bearings, working under loads and at sliding velocity, and maintaining other operating conditions, as assumed in theoretical research. The regula falsi iteration method was successfully implemented. The research results have con fi rmed the usefulness of various calculation methods since the values of selected characteristics of the journal bearing obtained were comparable.

  • Comparison of the Efficiency of Deammonification under Different DO Concentrations in a Laboratory-Scale Sequencing Batch Reactor
    • Hussein Al-Hazmi
    • Z. Yin
    • Dominika Grubba
    • Joanna Majtacz
    • Jacek Mąkinia
    2022 Pełny tekst Water

    The efficiency of deammonification depends on the cooperation of ammonium oxidizing bacteria and archaea (AOB/AOA), anaerobic ammonium oxidizing bacteria (AnAOB) and the effective suppression of nitrite oxidizing bacteria (NOB) that compete with AnAOB for nitrite (NO2 -N). One of the effective NOB suppression strategies is intermittent aeration. However, it is important to have a good understanding of the optimum dissolved oxygen (DO) value in the aeration period and optimize the non-aeration time used during the reaction phase. This study comprised the investigation of the effect of different DO set points (0.4, 0.7, 1.0 and 1.5 mg O2/L) under the same aeration length off/on (12/3 min). Moreover, three different intermittent aeration modes (9/3, 6/3, 3/3) under the same DO set point (0.7 mg O2/L) were more investigated. The experiment was conducted for 6 months (180 days) in a laboratory-scale sequencing batch reactor (SBR) with a working volume of 10 L. The results indicated that a high N removal efficiency was achieved 74% at the DO set point = 0.7 mg O2/L during aeration strategy off/on (6/3 min) due to the low nitrate production rate (NPR) 0.9 mg N/g VSS/h and high ammonium utilization rate (AUR) 13 mg N/g VSS/h (NPR/AUR = 0.06). Mathematical modeling results confirmed that the feasible DO set point 0.7 and intermittent aeration mode off/on (6/3 min) were especially suitable for the optimal balance between the NOB suppression and keeping high activities of AOB and anammox in the system.

  • Comparison of three methods of EPR retrospective dosimetry in watch glass
    • Agnieszka Marciniak
    • Małgorzata Juniewicz
    • Bartłomiej Ciesielski
    • Anita Prawdzik-Dampc
    • Jakub Karczewski
    2022 Pełny tekst Frontiers in Public Health

    In this article we present results of our follow-up studies of samples of watch glass obtained and examined within a framework of international intercomparison dosimetry project RENEB ILC 2021. We present three methods of dose reconstruction based on EPR measurements of these samples: calibration method (CM), added dose method (ADM) and added dose&heating method (ADHM). The study showed that the three methods of dose reconstruction gave reliable and similar results in 0.5–6.0Gy dose range, with accuracy better than 10%. The ADHM is the only one applicable in a real scenario, when sample-specific background spectrum is not available; therefore, a positive verification of this method is important for future use of EPR dosimetry in glass in potential radiation accidents

  • Comparison of thresholding algorithms for automatic overhead line detection procedure
    • Paweł Kowalski
    • Robert Smyk
    2022 Pełny tekst Przegląd Elektrotechniczny

    The article presents an overview of the thresholding algorithms. It compares the algorithms proposed by Pun, Kittler, Niblack, Huang, Rosenfeld, Remesh, Lloyd, Riddler, Otsu, Yanni, Kapur and Jawahar. Additionally, it was tested how the tuning of the Pun, Jawahar and Niblack methods affects the thresholding efficiency and proposed a combination of the Pun algorithm with a priori algorithm. All presented algorithms have been implemented and tested for effectiveness in detecting overhead lines.

  • Compensation of Voltage Drops in Trolleybus Supply System Using Battery-Based Buffer Station
    • Mikołaj Bartłomiejczyk
    • Leszek Jarzębowicz
    • Jiří Kohout
    2022 Pełny tekst ENERGIES

    This paper analyzes the results of a trial operation of a battery-based buffer station supporting a selected section of trolleybus power supply systems in Pilsen, Czech Republic. The buffer station aims to prevent the catenary from excessive voltage drops in a part of the route that is most remote from the traction substation. Compensation of voltage drops is carried out by continuously measuring the catenary voltage and injecting the current into the catenary if the voltage decreases below a preset value. The effectiveness of such a solution was evaluated by the analysis of numerous experimental recordings, both from the buffer station itself and from trolleybuses in operation. Further on, based on the recordings, a utilized battery capacity was estimated and a control method for decreasing the required capacity was proposed. The optimal capacity analysis, supplemented with an evaluation of required output current rating, was used to define the best storage technology for the considered application.

  • Composite Materials Based on Silicon Oxycarbide as Anodes for Lithium-Ion Batteries
    • Dominik Knozowski
    2022 Pełny tekst

    In this work, the properties of binary SiOC/graphite and SiOC/tin, as well as ternary SiOC/graphite/tin obtained from various preceramic precursors are described. During the first step, the materials were synthesized using various techniques such as sol-gel and hydrosilylation. To prevent sedimentation and agglomeration of graphite particles during the gelation stage without using surfactants and thickeners, a new gelation technique with utilizing simulations homogenisation and high-power ultrasounds was developed. This method enables a uniform distribution of graphite particles in a polymer blend. In addition, heat generated during this process shortens the gelation time from a few days to a few hours. In the second step, structural and electrochemical characterisation of the obtained materials was conducted. The carbon, ceramic and tin phases were carefully studied in terms of the quantity, structure, morphology, distribution, and in terms of possible reactions that could occur during the synthesis of the materials. In the case of electrochemical measurements, primary focus was on relationships between the content of the additives, the preceramic precursor type, and the resulting microstructure of the composites which influences their final electrochemical properties.

  • Composition Patterns of Contemporary Polish Residential Building Facades
    • Michał Malewczyk
    • Antoni Taraszkiewicz
    • Piotr Czyż
    2022 Nexus Network Journal

    This study aims to define the types of composition patterns of contemporary Polish multi-family building facades. The authors define the compositional patterns to determine their frequency. Analyses carried out on the basis of photos and visualizations of 113 examples of architecture from Poland identified groups of common features of facades. Statistical analyses of these features resulted in six types of compositions. Clear differences were noticed in relation to features, such as the repeatability of compositional elements and the method of building a vertical compositional axis. Variations were observed in the frequency and extent of application of specific types of compositions. The results of this study can be a starting point for the development of generative algorithms supporting the process of designing facades. Specifying the types will allow for further exploration of the theme, both in terms of the use of specific compositional measures and in terms of their perception.

  • Comprehensive analysis of low-temperature methods for reclaiming of ground tire rubber
    • Łukasz Zedler
    2022 Pełny tekst

    Management of waste tires has become an important topic for decades. The lack of an effective method to manage the materials as mentioned above leads to illegal landfills. This problematic waste can be divided into two main categories depending on the physical condition of the waste: (i) partially used tires; (ii) end-of-life tires. While the first group can be reused or retreaded, the second group requires special measures to manage it. At present, the most intensively researched method is the reclaiming of ground tire rubber (GTR). According to literature reports, many approaches have already been made to the subject, among which mechanical, thermal, chemical methods and their combinations have been used. However, the vast majority of these publications do not verify the environmental impact of processing and exploitation of the material. The following dissertation presents an analysis of the available literature on the topic of rubber waste management, as well as my research aimed at (i) developing a GTR processing technology to obtain a product with satisfactory functional properties, (ii) developing a research methodology for GTR-based products considering the gaps in the current state of knowledge, (iii) assessing the environmental impact of GTR processing, and (iv) evaluating the recycling potential of GTR-based products.

  • Comprehensive Enhancement of Prepolymer-Based Flexible Polyurethane Foams’ Performance by Introduction of Cost-Effective Waste-Based Ground Tire Rubber Particles
    • Wiktoria Żukowska
    • Paulina Kosmela
    • Paweł Wojtasz
    • Mariusz Szczepański
    • Adam Piasecki
    • Roman Barczewski
    • Mateusz Barczewski
    • Aleksander Hejna
    2022 Pełny tekst Materials

    Material innovations in polyurethane (PU) foams should ideally combine performance enhancement, environmental impact limitation, and cost reduction. These goals can be achieved by applying recycled or waste-based materials without broader industrial applications, implicating their low price. Herein, from 5 to 20 parts by weight of ground tire rubber (GTR) particles originated from the recycling of postconsumer car tires were incorporated into a flexible foamed PU matrix as a cost-effective waste-based filler. A two-step prepolymer method of foams manufacturing was applied to maximize the potential of applied formulation changes. The impact of the GTR content on the foams’ processing, chemical, and cellular structure, as well as static and dynamic mechanical properties, thermal stability, sound suppression ability, and thermal insulation performance, was investigated. The introduction of GTR caused a beneficial reduction in the average cell diameter, from 263.1 µm to 144.8–188.5 µm, implicating a 1.0–4.3% decrease in the thermal conductivity coefficient. Moreover, due to the excellent mechanical performance of the car tires—the primary application of GTR—the tensile performance of the foams was enhanced despite the disruption of the cellular structure resulting from the competitiveness between the hydroxyl groups of the applied polyols and on the surface of the GTR particles. The tensile strength and elongation at break were increased by 10 and 8% for 20 parts by weight GTR addition. Generally, the presented work indicates that GTR can be efficiently applied as a filler for flexible PU foams, which could simultaneously enhance their performance, reduce costs, and limit environmental impacts due to the application of waste-based material.

  • Comprehensive evaluation of the carbon footprint components of wastewater treatment plants located in the Baltic Sea region
    • Mojtaba Maktabifard
    • Alexis Awaitey
    • Elina Merta
    • Henri Haimi
    • Ewa Zaborowska
    • Anna Mikola
    • Jacek Mąkinia
    2022 Pełny tekst SCIENCE OF THE TOTAL ENVIRONMENT

    Finland and Poland share similar environmental interests with regard to their wastewater effluents eventually being discharged to the Baltic Sea. However, differences in the influent wastewater characteristics, treatment processes, operational conditions, and carbon intensities of energy mixes in both countries make these two countries interesting for carbon footprint (CF) comparison. This study aimed at proposing a functional unit (FU) which enables a comprehensive comparison of wastewater treatment plants (WWTPs) in terms of their CF. Direct emissions had the highest contribution (70%) to the total CF. Energy consumption dominated the total indirect emissions in both countries by over 30%. Polish WWTPs benefitted more from energy self-sufficiency than Finnish plants as a result of higher electricity emission factors in Poland. The main difference between indirect emissions of both countries were attributed to higher chemical consumption of the Finnish WWTPs. Total pollution equivalent removed (TPErem) FU proposed enabled a better comparison of WWTPs located in different countries in terms of their total CF. High correlations of TPErem with other FUs were found since TPErem could balance out the differences in the removal efficiencies of various pollutants. Offsetting CF was found a proper strategy for the studied WWTPs to move towards low-carbon operation. The studied WWTPs could reduce their CF from up to 27% by different practices, such as selling biofuel, electricity and fertilizers. These findings are applicable widely since the selected WWTPs represent the typical treatment solutions in Poland, Finland and in the Baltic Sea region.