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  • Mining inconsistent emotion recognition results with the multidimensional model
    • Agnieszka Landowska
    • Teresa Zawadzka
    • Michal Zawadzki
    2021 Pełny tekst IEEE Access

    The paper deals with the challenge of inconsistency in multichannel emotion recognition. The focus of the paper is to explore factors that might influence the inconsistency. The paper reports an experiment that used multi-camera facial expression analysis with multiple recognition systems. The data were analyzed using a multidimensional approach and data mining techniques. The study allowed us to explore camera location, occlusions and algorithm factors in the late fusion of emotion recognition results. We proposed to use a multidimensional data model for mining the various interdependencies between the factors of inconsistency. The study allowed the exploration of challenges in multichannel emotion recognition. It was achieved by comparing the consistency of obtained emotions and identification of rules determining conditions when the obtained emotions are consistent. However, the main novelty of the paper is the method of mining the inconsistencies. The study might be interesting both for researchers dealing with integration in emotion recognition, as well as for practitioners who use automatic emotion analysis software and expect to get valid results.

  • Mispronunciation Detection in Non-Native (L2) English with Uncertainty Modeling
    • Daniel Korzekwa
    • Jaime Lorenzo-trueba
    • Szymon Zaporowski
    • Shira Calamaro
    • Thomas Drugman
    • Bożena Kostek
    2021

    A common approach to the automatic detection of mispronunciation in language learning is to recognize the phonemes produced by a student and compare it to the expected pronunciation of a native speaker. This approach makes two simplifying assumptions: a) phonemes can be recognized from speech with high accuracy, b) there is a single correct way for a sentence to be pronounced. These assumptions do not always hold, which can result in a significant amount of false mispronunciation alarms. We propose a novel approach to overcome this problem based on two principles: a) taking into account uncertainty in the automatic phoneme recognition step, b) accounting for the fact that there may be multiple valid pronunciations. We evaluate the model on non-native (L2) English speech of German, Italian and Polish speakers, where it is shown to increase the precision of detecting mispronunciations by up to 18% (relative) compared to the common approach.

  • Mitigating the seismic pounding of multi-story buildings in series using linear and nonlinear fluid viscous dampers
    • Hytham Elwardany
    • Robert Jankowski
    • Ayman Seleemah
    2021 Pełny tekst Archives of Civil and Mechanical Engineering

    Seismic-induced pounding between adjacent buildings may have serious consequences, ranging from minor damage up to total collapse. Therefore, researchers try to mitigate the pounding problem using different methods, such as coupling the adjacent buildings with stiff beams, connecting them by using viscoelastic links, and installing damping devices in each building individually. In the current paper, the effect of using linear and nonlinear fluid viscous dampers to mitigate the mutual pounding between a series of structures is investigated. Nonlinear finite element analysis of a series of adjacent steel buildings equipped with damping devices was conducted. Contact surfaces with both contactor and target were used to model the mutual pounding. The results indicate that the use of linear or nonlinear dampers leads to the significant reduction in the response of adjacent buildings in series. Moreover, the substantial improvement of the performance of buildings has been observed for almost all stories. From the design point of view, it is concluded that dampers implemented in adjacent buildings should be designed to resist maximum force of 6.20 or 1.90times the design independent force in the case of using linear or nonlinear fluid viscous dampers, respectively. Also, designers should pay attention to the design of the structural elements surrounding dampers because considerable forces due to pounding may occur in the dampers at the maximum displaced position of the structure.

  • Mitigation effect of face shield to reduce SARS-CoV-2 airborne transmission risk: Preliminary simulations based on computed tomography
    • Dmitry Tretiakov
    • Krzysztof Tesch
    • Andrzej Skorek
    • Dmitry Tretiakow
    2021 Pełny tekst ENVIRONMENTAL RESEARCH

    We aimed to develop a model to quantitatively assess the potential effectiveness of face shield (visor) in reducing airborne transmission risk of the novel coronavirus SARS-CoV-2 during the current COVID-19 pandemic using the computational fluid dynamics (CFD) method. The studies with and without face shield in both an infected and healthy person have been considered in indoor environment simulation. In addition to the influence of the face shield and the synchronization of the breathing process while using the device, we also simulated the effect of small air movements on the SARS-CoV-2 infection rate (outdoor environment simulation). The contact with infectious particles in the case without a face shield was 12–20 s (s), in the presence of at least one person who was positive for SARS-CoV-2. If the infected person wore a face shield, no contact with contaminated air was observed during the entire simulation time (80 s). The time of contact with contaminated air (infection time) decreases to about 11 s when the surrounding air is still and begins to move at a low speed. Qualitative dif­ ferences between simulations performed on the patients with and without the face shield are clearly visible. The maximum prevention of contagion is probably a consequence of wearing a face shield by an infected person. Our results suggest that it is possible to determine contact with air contaminated by SARS-CoV-2 using the CFD method under realistic conditions for virtually any situation and configuration. The proposed method is probably the fastest and most reliable among those based on CFD-based techniques.

  • Mitochondrial DNA copy number and trimethylamine levels in the blood: New insights on cardiovascular disease biomarkers
    • Laura Bordoni
    • Irene Petracci
    • Iwona Pelikant-Malecka
    • Adrianna Radulska
    • Marco Piangerelli
    • Joanna J. Samulak
    • Lukasz Lewicki
    • Leszek Kalinowski
    • Rosita Gabbianelli
    • Robert A. Olek
    2021 Pełny tekst FASEB JOURNAL

    Among cardiovascular disease (CVD) biomarkers, the mitochondrial DNA copy number (mtDNAcn) is a promising candidate. A growing attention has been also dedicated to trimethylamine-N-oxide (TMAO), an oxidative derivative of the gut metabolite trimethylamine (TMA). With the aim to identify biomarkers predictive of CVD, we investigated TMA, TMAO, and mtDNAcn in a population of 389 coronary artery disease (CAD) patients and 151 healthy controls, in association with estab-lished risk factors for CVD (sex, age, hypertension, smoking, diabetes, glomerular filtration rate [GFR]) and troponin, an established marker of CAD. MtDNAcn was significantly lower in CAD patients; it correlates with GFR and TMA, but not with TMAO. A biomarker including mtDNAcn, sex, and hypertension (but neither TMA nor TMAO) emerged as a good predictor of CAD. Our findings support the mtD-NAcn as a promising plastic biomarker, useful to monitor the exposure to risk factors and the efficacy of preventive interventions for a personalized CAD risk reduction.

  • Mn-Co spinel coatings on Crofer 22 APU by electrophoretic deposition: Up scaling, performance in SOFC stack at 850 °C and compositional modifications
    • A Sabato
    • E Zanchi
    • Sebastian Molin
    • Grzegorz Cempura
    • H. Javed
    • K. Herbrig
    • C. Walter
    • A Boccaccini
    • Federico Smeacetto
    2021 JOURNAL OF THE EUROPEAN CERAMIC SOCIETY

    Ceramic coatings for metallic interconnects play a key role in limiting corrosion and chromium evaporation in solid oxide cells. This study presents the upscaling of the electrophoretic deposition (EPD) technique to process Mn-Co spinels on real-dimension Crofer 22 APU interconnects and the test in a SOFC stack. Area specific resistance of long-term test conducted for 5000 h at 850 °C demonstrated that two-steps sintering has a significant influence on the coating performance; an area specific resistance degradation rate of 0.5 mΩ cm2 kh−1 is recorded. Stack test, operated in fuel cell mode at 850 °C for 3000 h under application of 227 mA/cm², including 5 thermal cycles, demonstrated the effectiveness of the electrophoretically deposited Mn-Co spinel in limiting the oxide scale growth on the Crofer 22 APU. An advanced post mortem investigation showed the effectiveness of the EPD ceramic coating, even when considering different and complex surfaces of the Crofer 22 APU.

  • Mobile Gas Chromatographs Coupled with Mass and Ion Mobility Spectrometers and their Applications
    • Zygfryd Witkiewicz
    • Waldemar Wardencki
    2021 Pełny tekst Ecological Chemistry and Engineering S - Chemia i Inżynieria Ekologiczna S

    The articles describes the developments un combining of mass and ion mobility spectrometers (MS, IMS0 with miniature gas chromatographs (GC). The examples of applications of miniaturised GC-MS and GC-IMS devices are presented.

  • MobileNet family tailored for Raspberry Pi
    • Wojciech Glegoła
    • Aleksandra Karpus
    • Adam Przybyłek
    2021 Pełny tekst Procedia Computer Science

    With the advances in systems-on-a-chip technologies, there is a growing demand to deploy intelligent vision systems on low-cost microcomputers. To address this challenge, much of the recent research has focused on reducing the model size and computational complexity of contemporary convolutional neural networks (CNNs). The state-of-the-art lightweight CNN is MobileNetV3. However, it was designed to achieve a good trade-off between accuracy and latency on a single large core of a Google Pixel 1 smartphone. Accordingly, MobileNetV3 is not optimized for platforms with different hardware characteristics and its predecessors may perform better for a given target platform. The aim of this paper is twofold: 1) to analyze the performance of different compact CNNs on Raspberry Pi 4; 2) to manually adapted the most promising models to better utilize the Raspberry Pi 4 hardware. After exploring a number of modifications, we present a new CNN architecture, namely MobileNetV3-Small-Pi, which is 36% faster and slightly more accurate on ImageNet classification compared to the baseline MobileNetV3-Small.

  • Moda jako wartość konsumencka - eksplikacja zagadnienia
    • Anna Dembicka
    2021 Pełny tekst Problemy Jakości

    Cel: Celem artykułu jest przedstawienie problematyki mody jako propozycji wartości dla klienta. Realizacja niniejszego celu wymagała uszczegółowionej eksplikacji zjawiska mody. W publikacji zdefiniowaniu poddano mechanizm działania mody, istotę trendu mody, jak również omówiono główne perspektywy analizy mody oraz aktualne nurty badań nad modą. Projekt badania/metodyka badawcza/koncepcja: W pracy wykorzystano metodę krytycznej analizy literatury przedmiotu, mającej na celu identyfikację istotnych dla tematu zagadnień, metodę syntezy oraz wnioskowania logicznego i na ich podstawie podjęto próbę konsolidacji dystynktywnej, statusowej i ekspresywnej roli mody, stanowiącej wartość dla klienta. Interdyscyplinarność zjawiska mody wpłynęła na charakter doboru literatury. Artykuł ma charakter przeglądowy. Wyniki/wnioski: Poznanie psychologicznych, socjologicznych i ekonomicznych źródeł mody oraz motywów wpływających na uleganie jej mechanizmowi umożliwia pełniejsze zrozumienie oczekiwań nabywcy towarów i usług poddawanych odziaływaniu trendów mody i tworzenie konkurencyjnych ofert sprzedażowych. Ograniczenia: Ujmowanie mody jako wartości nabywczej wymaga bardziej pogłębionych analiz, głównie ze względu na wielokontekstowość zjawiska mody. Kierunkiem przyszłych badań autorki będzie ujawnienie zależności pomiędzy kompatybilną triadą wartości dla klienta w przemyśle jachtowym: modą, zabawą i estetyką. Zastosowanie praktyczne: Niniejsze opracowanie stanowić może swoiste kompendium analiz wykorzystywanych w strategiach marketingu zróżnicowanego oferentów dóbr luksusowych. Oryginalność/wartość poznawcza: Artykuł opisuje zjawisko mody z perspektywy zachowań konsumenckich, ujawniając równocześnie uniwersalne spektrum jej charakterystyki. Zdaniem autorki weryfikacja znaczenia mody, w zróżnicowanych pod względem oferty sprzedażowej sektorach, sprzyja dywersyfikacji i porządkowaniu wiedzy na jej temat.

  • Model obliczania kosztu cyklu życia obiektu na przykładzie budynku mieszkalnego jednorodzinnego
    • Adam Kristowski
    • Beata Grzyl
    • Marcin Szczepański
    • Anna Jakubczyk-Gałczyńska
    2021 Przegląd Budowlany

    W artykule przedstawiono model obliczania kosztu cyklu życia budynku mieszkalnego jednorodzinnego oraz wskazano możliwości ograniczenia wydatków związanych z jego użytkowaniem w okresie trzydziestu lat. Celem prezentowanej analizy rachunku kosztu cyklu życia jest porównanie i ocena kosztów nabycia i użytkowania domu realizowanego według alternatywnych technologii z uwzględnieniem przyjętych rozwiązań w zakresie pozyskania energii, wykorzystanych materiałów, systemów grzewczych i wentylacji. Otrzymane rezultaty wskazują na korzyści płynące z wykorzystania w praktyce algorytmu przedstawionego w artykule.

  • Model-Based Adaptive Machine Learning Approach in Concrete Mix Design
    • Patryk Ziółkowski
    • Maciej Niedostatkiewicz
    • Shao-Bo Kang
    2021 Pełny tekst Materials

    Concrete mix design is one of the most critical issues in concrete technology. This process aims to create a concrete mix which helps deliver concrete with desired features and quality. Contemporary requirements for concrete concern not only its structural properties, but also increasingly its production process and environmental friendliness, forcing concrete producers to use both chemically and technologically complex concrete mixtures. The concrete mix design methods currently used in engineering practice are joint analytical and laboratory procedures derived from the Three Equation Method and do not perform well enough for the needs of modern concrete technology. This often causes difficulties in predicting the final properties of the designed mix and leads to precautionary oversizing of concrete properties for fear of not providing the required parameters. A new approach that would make it possible to predict the newly designed concrete mix properties is highly desirable. The answer to this challenge can be methods based on machine learning, which have been intensively developed in recent years, especially in predicting concrete compressive strength. Machine learning-based methods have been more or less successful in predicting concrete compressive strength, but they do not reflect well the variability that characterises the currently used concrete mixes. A new adaptive solution that allows estimating concrete compressive strength on the basis of the concrete mix main ingredient composition by including two observations for a given batch of concrete is proposed herein. In presented study, a machine learning model was built with a deep neural network architecture, trained on an extensive database of concrete recipes, and translated into a mathematical formula. Testing on four concrete mix recipes was performed, which were calculated according to contemporary design methods (Bolomey and Fuller method), and a comparative analysis was conducted. It was found out that the new algorithm performs significantly better than that without adaptive features trained on the same dataset. The presented algorithm can be used as a concrete strength checking tool for the concrete mix design process.

  • Modeling an Industrial Revolution: How to Manage Large-Scale, Complex IoT Ecosystems?
    • Geza Kulcsar
    • Pal Varga
    • Marek Tatara
    • Federico Montori
    • Michel A. Inigo
    • Gianvito Urgese
    • Paolo Azzoni
    2021 Pełny tekst

    Advancements around the modern digital industry gave birth to a number of closely interrelated concepts: in the age of the Internet of Things (IoT), System of Systems (SoS), Cyber-Physical Systems (CPS), Digital Twins and the fourth industrial revolution, everything revolves around the issue of designing well-understood, sound and secure complex systems while providing maximum flexibility, autonomy and dynamics. The aim of the paper is to present a concise overview of a comprehensive conceptual framework for integrated modeling and management of industrial IoT architectures, supported by actual evidence from the Arrowhead Tools project; in particular, we adopt a three-dimensional projection of our complex engineering space, from modeling the engineering process to SoS design and deployment. In particular, we start from modeling principles of the the engineering process itself. Then, we present a design-time SoS representation along with a toolchain concept aiding SoS design and deployment. This brings us to reasoning about what potential workflows are thinkable for specifying comprehensive toolchains along with their data exchange interfaces. We also discuss the potential of aligning our vision with RAMI4.0, as well as the utilization perspectives for real-life engineering use-cases.

  • Modeling and Evaluation of Electric Treeing Phenomena in Polymeric Cable Insulation
    • Qasim Khan
    • Shady S. Refaat
    • Haitham Abu-Rub
    • Hamid Toliyat
    • Marek Olesz
    2021

    This paper investigates the treeing phenomenon in polymeric materials such as crosslinked polyethylene (XLPE) that is widely used in medium and high voltage power cables as primary insulation. The modeling of electrical tree growth in the insulation from its initiation to breakdown is significant research work that illustrates the discharge dynamics and its impact on aging process in polymeric insulation. This study utilizes pulse sequence analysis (PSA) mapping and phase-resolved partial discharge (PRPD) pattern to model the tree growth and its correlation with the aging in the XLPE samples. The applied electric stress magnitude as a crucial treeing aspect is utilized to comprehend treeing and its relationship with insulation degradation. The tree mapping and plots exemplify and characterize treeing stages to work as a reliable diagnostic tool to determine aging in solid insulation.

  • Modeling of Electrified Transportation Systems Featuring Multiple Vehicles and Complex Power Supply Layout
    • Aleksander Jakubowski
    • Leszek Jarzębowicz
    • Mikołaj Bartłomiejczyk
    • Jacek Skibicki
    • Sławomir Judek
    • Andrzej Wilk
    • Mateusz Płonka
    2021 Pełny tekst ENERGIES

    The paper proposes a novel approach to modeling electrified transportation systems. The proposed solution reflects the mechanical dynamics of vehicles as well as the distribution and losses of electric supply. Moreover, energy conversion losses between the mechanical and electrical subsystems and their bilateral influences are included. Such a complete model makes it possible to replicate, e.g., the impact of voltage drops on vehicle acceleration or the necessity of partial disposal of regenerative braking energy due to temporary lack of power transmission capability. The modeling methodology uses a flexible twin data-bus structure, which poses no limitation on the number of vehicles and enables modeling complex traction power supply structures. The proposed solution is suitable for various electrified transportation systems including suburban and urban systems. The modeling methodology is applicable i.a. to Matlab/Simulink, which makes it broadly available and customizable, and provides short computation time. The applicability and accuracy of the method were verified by comparing simulation and measurement results on an exemplary trolleybus system operating in Pilsen, Czech Republic. Simulation of daily operation of an area including four supply sections and maximal simultaneous number of nine vehicles showed a good conformance with the measured data, with the difference in the total consumed energy not exceeding 5%.

  • Modeling of Passive and Forced Convection Heat Transfer in Channels with Rib Turbulators
    • Jan Stąsiek
    • Adam Stąsiek
    • Marek Szkodo
    2021 Pełny tekst ENERGIES

    The main goal of the research presented in this paper was the experimental and numerical analysis of heat enhancement and aerodynamic phenomena during air flow in a channel equipped with flow turbulators in the form of properly configured ribs. The use of ribs intensifies the heat transfer and at the same time increases not only the flow resistance but also the energy costs. Therefore, designing modern heat exchangers with optimal thermal and flow parameters requires the knowledge of the theory of heat exchangers as well as measurement methods and numerical calculations. Bearing in mind the above, the liquid crystal techniques (LCT), particle image velocimetry (PIV) and digital image processing (DIP) for temperature, velocity, friction factor and heat transfer coefficient measurements are presented herein. These three optical tools (using desktop computers) create an extremely powerful and advanced measuring technique that has not been available anywhere before. Brief histories of these measurement methods and techniques are discussed and some examples are presented. In order to assess and select the value of the measurement technique, local and average distributions of Nusselt numbers (in the measurement section) obtained by the transit analysis method on the inter-rib regions of a plate coated by thermochromics liquid crystal and heated by air as an alternative to the steady-state analysis. In the parallel, numerical calculation was performed with the use of the ANSYS Fluent software code and supported by laser anemometrycomputed turbulence intensity of air flow. Comparison of the Nusselt number distributions was determined by three methods, i.e., steady state, the transient method and CFD simulation. Up to three-fold enhancement of the local heat transfer capability was observed. Failure to take into account the surface of the ribs in heat transfer causes differences in the obtained results of the Nusselt number depending on the method used. Apart from the heat transfer data, the pressure drop in the form of friction factors is also presented. On the basis of the conducted research, it can be stated that both qualitative and quantitative coherence was obtained between the experimental and computational studies.

  • Modeling protein structures with the coarse-grained UNRES force field in the CASP14 experiment
    • Anna Antoniak
    • Iga Biskupek
    • Krzysztof K. Bojarski
    • Cezary Czaplewski
    • Artur Giełdoń
    • Mateusz Kogut
    • Małgorzata M. Kogut
    • Paweł Krupa
    • Agnieszka Lipska
    • Adam Liwo
    • Emilia Lubecka
    • Mateusz Marcisz
    • Martyna Maszota-Zieleniak
    • Sergey A. Samsonov
    • Adam K. Sieradzan
    • Magdalena J. Ślusarz
    • Rafał Ślusarz
    • Patryk A. Wesołowski
    • Karolina Ziȩba
    2021 Pełny tekst JOURNAL OF MOLECULAR GRAPHICS & MODELLING

    The UNited RESidue (UNRES) force field was tested in the 14th Community Wide Experiment on the Critical Assessment of Techniques for Protein Structure Prediction (CASP14), in which larger oligomeric and multimeric targets were present compared to previous editions. Three prediction modes were tested (i) ab initio (the UNRES group), (ii) contact-assisted (the UNRES- contact group), and (iii) template-assisted (the UNRES-template group). For most of the targets, the contact restraints were derived from the server models top-ranked by the DeepQA method, while the DNCON2 method was used for 11 targets. Our consensus- fragment procedure was used to run template-assisted predictions. Each group also processed the Nuclear Magnetic Resonance (NMR)- and Small Angle X-Ray Scattering (SAXS)-data assisted targets. The average Global Distance Test Total Score (GDT TS) of the ‘Model 1’ predictions were 29.17, 39.32, and 56.37 for the UNRES, UNRES-contact, and UNRES-template predictions, respectively, increasing by 0.53, 2.24, and 3.76, respectively, compared to CASP13. It was also found that the GDT TS of the UNRES models obtained in ab initio mode and in the contact-assisted mode decreases with the square root of chain length, while the exponent in this relationship is 0.20 for the UNRES-template group models and 0.11 for the best performing AlphaFold2 models, which suggests that incorporation of database information, which stems from protein evolution, brings in long-range correlations, thus enabling the correction of force-field inaccuracies.

  • Modeling SARS‐CoV‐2 proteins in the CASP‐commons experiment
    • Andriy Kryshtafovych
    • John Moult
    • Wendy M. Billings
    • Dennis Della Corte
    • Krzysztof Fidelis
    • Sohee Kwon
    • Kliment Olechnovič
    • Chaok Seok
    • Česlovas Venclovas
    • Jonghun Won
    • Alphafold Team
    • Badri Adhikari
    • Recep Adiyaman
    • Joaquim Aguirre-plans
    • Ivan Anishchenko
    • Minkyung Baek
    • David Baker
    • Frederico Baldassarre
    • Jacob Barger
    • Sutanu Bhattacharya
    • Debswapna Bhattacharya
    • Mor Bitton
    • Renzhi Cao
    • Jianlin Cheng
    • Charles Christoffer
    • Cezary Czaplewski
    • Zongyang Du
    • Arne Elofsson
    • Eshel Faraggi
    • Michael Feig
    • Narcis Fernandez-fuentes
    • Nick Grishin
    • Sergei Grudinin
    • Zhiye Guo
    • Yuya Hanazono
    • Demis Hassabis
    • Bryce Hedelius
    • Lim Heo
    • Naozumi Hiranuma
    • Cassandra Hunt
    • Ilia Igashov
    • Takashi Ishida
    • Robert L. Jernigan
    • David Jones
    • John Jumper
    • Maria Kadukova
    • Shaun Kandathil
    • Chen Keasar
    • Daisuke Kihara
    • Lisa Kinch
    • Yasuomi Kiyota
    • Andrzej Kloczkowski
    • Pushmeet Kohli
    • Mateusz Kogut
    • Elodie Laine
    • Cade Lilley
    • Jian Liu
    • Adam Liwo
    • Emilia Lubecka
    • Arup Mondal
    • Connor J. Morris
    • Liam Mcguffin
    • Alexis Molina
    • Tsukasa Nakamura
    • Baldo Oliva
    • Alberto Perez
    • Gabriele Pozzati
    • Daipayan Sarkar
    • Rin Sato
    • Torsten Schwede
    • Bikash Shrestha
    • Tomer Sidi
    • Gabriel Studer
    • Md Hossain Shuvo
    • Mayuko Takeda-shitaka
    • Yuma Takei
    • Genki Terashi
    • Kentaro Tomii
    • Yuko Tsuchiya
    • Kathryn Tunyasuvunakool
    • Bjorn Wallner
    • Tianqi Wu
    • Jinbo Xu
    • Yu Yamamori
    • Jianyi Yang
    • Lisha Ye
    • Chengxin Zhang
    • Yang Zhang
    • Wei Zheng
    2021 PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS

    Critical Assessment of Structure Prediction (CASP) is an organization aimed at advancing the state of the art in computing protein structure from sequence. In the spring of 2020, CASP launched a community project to compute the structures of the most structurally challenging proteins coded for in the SARS-CoV-2 genome. Forty-seven research groups submitted over 3000 three-dimensional models and 700 sets of accuracy estimates on 10 proteins. The resulting models were released to the public. CASP community members also worked together to provide estimates of local and global accuracy and identify structure-based domain boundaries for some proteins. Subsequently, two of these structures (ORF3a and ORF8) have been solved experimentally, allowing assessment of both model quality and the accuracy estimates. Models from the AlphaFold2 group were found to have good agreement with the experimental structures, with main chain GDT_TS accuracy scores ranging from 63 (a correct topology) to 87 (competitive with experiment).

  • Modelling AOB-NOB competition in shortcut nitrification compared with conventional nitrification-denitrification process
    • Jakub Drewnowski
    • Mehdi Sharifshourjeh
    • Przemysław Kowal
    • W Cel
    2021 Pełny tekst Journal of Physics : Conference Series

    In particular, mainstream deammonification and/or shortened nitrificationdenitrification via nitrite (so-called “nitrite shunt”) is a promising new treatment concept that has the potential to revolutionise how nitrogen removal is achieved at WWTPs. Understanding the role of the AOB/NOB competition in the nitrogen cycle in wastewater treatment systems will change operational strategies of the novel nitrogen removal processes. The key role in this process is inhibition of NOB activity undesirably affects AOB activity and leads to inefficient partial nitrification process and when used as pre-treatment for Anammox it can limit nitrite supply to Anammox bacteria. Successful NOB repression requires a combination of such factors as a low DO concentration, a rapid transition from aerobic to anoxic conditions, and tight control of Temperature and/or pH. The major driving force behind the successful NOB washout is the inhibition of those bacteria based on the difference in the growth rate between AOB and NOB. The obtained results from this study show the mechanisms and operating conditions (e.g. DO concentration, Temp.) leading to complete domination of AOB over NOB under aerobic conditions. This paper presents the perspectives on modelling AOB-NOB competition in shortcut nitrification. The combined deammonification, shortened nitrification-denitrification and/or nitritation-anammox process was compared with conventional nitrification-denitrification based on own experiments and literature data. Its successful application as shortcut nitrification technology and new control system will represent a paradigm shift for the wastewater industry, offering the opportunity for sustainable wastewater treatment, energy-neutral or even energypositive facilities, and substantial reductions in treatment costs.

  • Modelling Long‐Term Transition from Coal‐Reliant to Low‐Emission Power Grid and District Heating Systems in Poland
    • Marcin Jaskólski
    • Paweł Bućko
    2021 Pełny tekst ENERGIES

    Energy systems require technological changes towards climate neutrality. In Poland, where the power system is dominated by outdated coal-fired power plants, efforts to minimize the environmental impact are associated with high costs. Therefore, optimal paths for the development of the energy sector should be sought in order to achieve ambitious long-term strategic goals, while minimizing the negative impact on the consumers’ home budget. A methodology and a model for the development of the electricity and heat generation structure were developed and implemented in market allocation (MARKAL) modelling framework. Two scenarios were presented, i.e., business as usual (BAU) and withdrawal from coal (WFC) scenarios. The calculations showed a significant role of nuclear energy and offshore wind power in the pursuit of climate neutrality of electricity generation. In the BAU scenario, the model proposes to stay with coal technologies using carbon capture and storage systems. Withdrawal from coal (WFC scenario) makes it necessary to replace them by gas-fired power plants with CO2 sequestration. Solar energy can be used both in electricity and district heating. In order to build on the latter technological option, appropriate energy storage techniques must be developed. Geothermal energy is expected to be the key option for district heat generation in the long-term horizon. The proposed development paths guarantee a significant reduction in greenhouse gases and industrial emissions. However, complete climate neutrality is uncertain, given the current degree and dynamics of technological development.

  • Modelling of dark fermentation of glucose and sour cabbage
    • Gaweł Sołowski
    • Krzysztof Pastuszak
    2021 Pełny tekst Heliyon

    In the article, modified Anaerobic Digestion Models 1 (ADM-1) was tested for modelling dark fermentation for hydrogen production. The model refitting was done with the Euler method. The new model was based on sets of differential equations. The model was checked for hydrogen production from sour cabbage in batch and semi-batch in 5 g VSS (volatile solid suspension)/L and at the semi-batch process from glucose at 5 and 10 g VSS/L. Added parameters determined the conversion of a substrate, hydrogen production, and stress parameters. In the case of a semi-batch process, for one month, cumulative hydrogen production from sour cabbage of 5 g VSS/L was 0.9 L of cumulative hydrogen volume and from glucose 5 g VSS/L (in case of feeding 2 g VSS/L every two days) 2.5 L of cumulative hydrogen volume. At the bacterial population level, hydrogen production was a continuous process at an adequate range of population size and environmental parameters

  • Modelling of full-scale silo experiments with flow correcting inserts using material point method (MPM) based on hypoplasticity.
    • Jakub Krzyżanowski
    • Andrzej Tejchman-Konarzewski
    • Michał Wójcik
    2021 POWDER TECHNOLOGY

    Charakterystyki przepływu materiałów sypkich w silosach mają znaczenie dla naporów wywieranych na ściany silosu. Można je zmieniać za pomocą różnych wkładek. W pracy omówiono wyniki liczbowe dotyczące ograniczonego przepływu niespoistego ziarnistego piasku w pełnowymiarowym silosie metalowym z różnymi symetrycznie rozmieszczonymi wkładami, służącymi do korekcji wzorca przepływu (podwójny stożek, stożek w stożku i odwrócony stożek). Do symulacji dynamicznego przepływu piasku w silosie zastosowano metodę punktu materialnego (MPM). Do opisu zachowania płynięcia piasku niespoistego przyjęto hipoplastyczny model konstytutywny. Nacisk położono na schematy przepływu i napory na ściany i wkładki silosu. Wyniki liczbowe zostały bezpośrednio porównane z odpowiednimi eksperymentami w silosie pełnowymiarowym. Osiągnięto zadowalającą zgodność wyników liczbowych i eksperymentalnych. W obliczeniach MPM zbadano również wpływ początkowego współczynnika porowatości piasku, kąta tarcia ściany silosu, położenia wkładki silosowej i rozmiaru komórek siatki MPM.

  • Modelling of shear zones during quasi-static granular silo flow using material point method (MPM)
    • Jakub Krzyżanowski
    • Andrzej Tejchman-Konarzewski
    • Wojciech Sołowski
    • Michał Wójcik
    2021 Pełny tekst POWDER TECHNOLOGY

    The paper focuses on confined silo flow of cohesionless sand. The problem considered is a quasi-static flow in a plane strain model silo with parallel walls simulated with the material point method (MPM). The simulation used a non-local hypoplastic constitutive model. Initially, the paper validated the implemented numerical approach with basic element tests and a plane strain compression test. The subsequent MPM calculations for a model silo were performed with different initial void ratios of sand and silo wall roughness. The flow simulations took also into account the different both location and width of the outlet. The emphasis was on the evolution of both shear zones (wall and internal curvilinear shear zones) and their impact on wall stresses/forces during flow. The numerical findings enhance the understanding of shear localization in granular materials during confined controlled flow in silos and its immense effect on the magnitude and distribution of wall pressures.

  • MODERNIZACJA DYDAKTYCZNEGO STANOWISKA LABORATORYJNEGO UMOŻLIWIAJĄCEGO ANALIZĘ PORÓWNAWCZĄ SPRAWNOŚCI ŚRUB NAPĘDOWYCH JACHTU MOTOROWEGO
    • Piotr Bzura
    2021 Pełny tekst Journal of Polish CIMEEAC

    W artykule przedstawiono autorską metodę wyznaczania sprawności działania różnych śrub napędowych jachtu motorowego na podstawie wyników badań wykonanych na zmodernizowanym stanowisku laboratoryjnym. Modernizacja stanowiska składającego się ze źródła mocy w postaci silnika elektrycznego, części pośredniczącej i pędnika polegała na dodaniu przetwornika częstotliwości umożliwiającego starowanie silnikiem elektrycznym, czujnika do pomiaru prędkości wody względem pędnika i zanurzenia pędnika (śruby napędowej) w kanale przepływowym. Na podstawie analizy przeprowadzonych badań został przedstawiony algorytm, według którego porównano dwie różne śruby napędowe.

  • Modification of cellulosic filler with diisocyanates – volatile organic compounds emission assessment and stability of chemical structure over time
    • Aleksander Hejna
    • Mariusz Marć
    • Jerzy Korol
    2021 Pełny tekst NORDIC PULP & PAPER RESEARCH JOURNAL

    This paper investigated the impact of type and content of diisocyanate on the structure of modified cellulose fillers. Four the most popular isocyanates were applied – isophorone, hexamethylene, toluene and methylene diphenyl diisocyanate – at loadings of 1–15 wt%. Chemical structure, and its short-term storage stability, were investigated for eight weeks. Moreover, the main volatile organic compounds detected during modification, as well as emitted from fillers before and after storage, were identified. The main compounds detected in the air during modifications were terpenes and terpenoids. No diisocyanates were detected, which is very beneficial considering their toxicity. They were emitted from modified fillers at 40 °C, but only from fresh samples. After storage no emissions were noted, which indicated successful modification of fillers, also confirmed by FTIR spectroscopy and changes in polarity of fillers’ surface. Observed changes should be considered beneficial for the potential applications of modified fillers in manufacturing of polymer composites.

  • Modification of structured bio‑carbon derived from spongin-based scaffolds with nickel compounds to produce a functional catalyst for reduction and oxidation reactions: Potential for use in environmental protection
    • Sonia Żółtowska
    • Zuzanna Bielan
    • Joanna Zembrzuska
    • Katarzyna Siwińska-Ciesielczyk
    • Adam Piasecki
    • Anna Zielińska-Jurek
    • Teofil Jesionowski
    2021 Pełny tekst SCIENCE OF THE TOTAL ENVIRONMENT

    Three different 3D fibrous-like NiO/Ni(OH)2/Ni‑carbonized spongin-based materials were prepared via a simple sorption–reduction method. Depending on the support used, the catalysts were composed of carbon, nickel oxide, nickel hydroxide and zero-valent nickel, with the surface content of the nickel-containing phase in the range 15.2–26.0 wt%. Catalytic studies showed promising activity in the oxidation of phenolic compounds in water and in the reduction of 4-nitrophenol. The oxidation efficiency depends on the substrate used and ranges from 80% for phenol at pH 2 to 99% for 4-chlorophenoxyacetic acid (4-CPA) and methylchlorophenoxypropionic acid (MCPP). In the reduction reaction, all catalysts exhibited superior activity, with rate constants in the range 0.648–1.022 min-1. The work also includes a detailed investigation of reusability and kinetic studies.

  • Modified Inductive Multi-Coil Wireless Power Transfer Approach Based On Z-Source Network
    • Bohdan Pakhaliuk
    • Oleksandr Husev
    • Viktor Shevchenko
    • Janis Zakis
    • Maksym Khomenko
    • Ryszard Strzelecki
    2021 Pełny tekst IEEE JOURNAL OF EMERGING AND SELECTED TOPICS IN POWER ELECTRONICS

    This article presents a non-conventional approach to a multi-coil wireless power transfer system based on a Z-source network. The novelty of the approach lies in the use of a Z-source as a voltage source for energy transmission through the wireless power transfer coils. The main advantage is in a reduced number of semiconductors. This paper provides the design approach, simulation and experimental study. Feasibility and possible application fields are presented in the conclusions.

  • Modified SPWM Technique with Zero-Sequence Voltage Injection for a Five-Phase, Three-Level NPC Inverter
    • Charles Odeh
    • Dmytro Kondratenko
    • Arkadiusz Lewicki
    • Andrzej Jąderko
    2021 Pełny tekst ENERGIES

    This article presents a modified sinusoidal pulse-width modulation (SPWM) scheme for a five-phase, three-level neutral-point-clamped inverter. The modulation scheme deploys a modified min–max function to inject the zero-sequence components into the reference modulating signals; hence enabling the effective utilization of the DC-link voltage. Balanced split-input DC-link voltages were achieved through further incorporation of adjustable voltage-dependent variables into the reference signals. The dynamic performance of the control approach is demonstrated through simulations and experiments on a laboratory inverter prototype; the results are well presented.

  • Modular Approach for Modelling Warming Up Process in Water Installations with Flow-Regulating Elements
    • Jacek Kropiwnicki
    • Mariusz Furmanek
    • Andrzej Rogala
    2021 Pełny tekst ENERGIES

    The paper presents a new method for modelling the warming up process of a water system with elements regulating the flow in a stochastic manner. The paper presents the basic equations describing the work of typical elements which the water installation is composed of. In the proposed method, a new computational algorithm was used in the form of an iterative procedure enabling the use of boundary conditions that can be stochastically modified during the warming-up process. A typical situation, when such a modification is processed, is the regulation of the medium flow through two-way or three-way valves or applying additional heat source. Moreover, the presented method does not require the transformation of the differential equations, describing the operation of individual elements, into a linear form, which significantly facilitates analytical work and makes it more flexible. The example of analysis of the operation of water installation used for controlling temperature of the process gases in a chemical installation shows the functionality and flexibility of the method. The adopted calculation schematics enable changing the direction of the heat flow while the heat exchanger is in operation. Additionally, the sequence of calculation processed in modules describing operation of installation elements is elective (there is no situation that output parameters from one element are used as input parameters for other element in the same calculation step).

  • Modyfikacja cementu kostnego w celu uzyskania długotrwałej ochrony antybakteryjnej
    • Marcin Wekwejt
    2021

    Niniejsza rozprawa doktorska stanowi przewodnik po jednotematycznym cyklu publikacji, dotyczącym modyfikacji akrylowego cementu kostnego celem uzyskania długotrwałej i efektywnej ochrony antybakteryjnej. W ramach niego przeprowadzono badania eksperymentalne polegające na opracowaniu technologii wytwarzania modyfikowanego cementu kostnego oraz procedury medycznej jego stosowania. Cement kostny był modyfikowany przez zastosowanie trzech typów dodatków w różnych stężeniach: antybakteryjnych (nanocząstek srebra, miedzi lub ich kombinacji), biodegradowalnych (celuloza, chitozan, trójfosforan wapnia, polidioksanon i magnez) oraz bioaktywnych (bioszkło 45S5 i 1393-B3). W badaniach oceniano zależność między składem cementu, zwłaszcza rodzajami i stężeniami dodatków, a jego właściwościami fizyczno-chemicznymi, mechanicznymi oraz biologicznymi. Uzyskane wyniki pozwoliły na dobór optymalnego składu chemicznego cementu kompozytowego, w którym dodatek nanosrebra wynosi 1,5% mas., zaś bioaktywnego szkła 5,0 % mas. W zależności od medycznego przeznaczenia, domieszkowany nanosrebrem cement zawierający bioszkło 45S5 zaleca się do zastosowań jako substytut kości z profilaktyczną osłoną antybakteryjną, natomiast cement wzbogacony bioszkłem 1393-B3 do zastosowań terapeutycznych w celu zwalczenia infekcji. Opracowane cementy pozwalają znacząco eliminować problemy związane ze stosowaniem dotychczasowych cementów w praktyce klinicznej.

  • Molecular basis of essentiality of early critical steps in the lipopolysaccharide biogenesis in Escherichia coli K-12: requirement of MsbA, cardiolipin, LpxL, LpxM and GcvB
    • Patrycja Gorzelak
    • Gracjana Klein-Raina
    • Satish Raina
    2021 Pełny tekst INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    To identify the physiological factors that limit the growth of Escherichia coli K-12 strains synthesizing minimal lipopolysaccharide (LPS), we describe the first construction of strains devoid of the entire waa locus and concomitantly lacking all three acyltransferases (LpxL/LpxM/LpxP), synthesizing minimal lipid IVA derivatives with a restricted ability to grow at around 21 °C. Suppressors restoring growth up to 37 °C of Δ(gmhD-waaA) identified two independent single-amino-acid substitutions—P50S and R310S—in the LPS flippase MsbA. Interestingly, the cardiolipin synthase-encoding gene clsA was found to be essential for the growth of ΔlpxLMP, ΔlpxL, ΔwaaA, and Δ(gmhD-waaA) bacteria, with a conditional lethal phenotype of Δ(clsA lpxM), which could be overcome by suppressor mutations in MsbA. Suppressor mutations basS A20D or basR G53V, causing a constitutive incorporation of phosphoethanolamine (P-EtN) in the lipid A, could abolish the Ca++ sensitivity of Δ(waaC eptB), thereby compensating for P-EtN absence on the second Kdo. A single-amino-acid OppA S273G substitution is shown to overcome the synthetic lethality of Δ(waaC surA) bacteria, consistent with the chaperone-like function of the OppA oligopeptide-binding protein. Furthermore, overexpression of GcvB sRNA was found to repress the accumulation of LpxC and suppress the lethality of LapAB absence. Thus, this study identifies new and limiting factors in regulating LPS biosynthesis.

  • Molecular Dynamics to Predict Cryo-EM: Capturing Transitions and Short-Lived Conformational States of Biomolecules
    • Łukasz Nierzwicki
    • Giulia Palermo
    2021 Pełny tekst Frontiers in Molecular Biosciences

    Single-particle cryogenic electron microscopy (cryo-EM) has revolutionized the field of the structural biology, providing an access to the atomic resolution structures of large biomolecular complexes in their near-native environment. Today’s cryo-EM maps can frequently reach the atomic-level resolution, while often containing a range of resolutions, with conformationally variable regions obtained at 6 Å or worse. Low resolution density maps obtained for protein flexible domains, as well as the ensemble of coexisting conformational states arising from cryo-EM, poses new challenges and opportunities for Molecular Dynamics (MD) simulations. With the ability to describe the biomolecular dynamics at the atomic level, MD can extend the capabilities of cryo-EM, capturing the conformational variability and predicting biologically relevant short-lived conformational states. Here, we report about the state-of-the-art MD procedures that are currently used to refine, reconstruct and interpret cryo-EM maps. We show the capability of MD to predict short-lived conformational states, finding remarkable confirmation by cryo-EM structures subsequently solved. This has been the case of the CRISPR-Cas9 genome editing machinery, whose catalytically active structure has been predicted through both long-time scale MD and enhanced sampling techniques 2 years earlier than cryo-EM. In summary, this contribution remarks the ability of MD to complement cryo-EM, describing conformational landscapes and relating structural transitions to function, ultimately discerning relevant short-lived conformational states and providing mechanistic knowledge of biological function.

  • Molecular level interpretation of excess infrared spectroscopy
    • Maciej Śmiechowski
    2021 Pełny tekst JOURNAL OF MOLECULAR LIQUIDS

    Infrared (IR) spectroscopy is an invaluable tool in studying intermolecular interactions in solvent mixtures. The deviation of the IR spectrum of a mixture from the spectra of its pure components is a sensitive measure of the non-ideality of solutions and the modulation of intermolecular interactions introduced by mutual influence of the components. Excess IR spectroscopy, based on the established notion of excess thermodynamic functions, provides a well-defined picture of such deviation. On the other hand, the difference spectra method strives to obtain so-called affected spectra by numerically removing the bulk component contribution until the IR spectrum of the spectrally affected component is isolated. Although tremendously useful, excess IR spectroscopy remains poorly studied from a computational point of view. Based on ab initio molecular dynamics (AIMD) simulations, IR spectra of a dimethyl sulfoxide (DMSO)–γ-butyrolactone (GBL) liquid mixture are obtained here from first principles, without resorting to experimental input. Using dipolar decomposition techniques, the excess IR spectrum is further analyzed by rigorously separating the contributions from the modulation of the intra- and intermolecular parts of the spectra of both components and the mutual interaction spectrum. It is found that while the intramolecular part of excess IR spectrum is a good predictor of its overall shape, the intermolecular parts are crucial for elucidation of the band shifts and fine details of the IR spectrum of the mixture. Furthermore, the affected IR spectrum is obtained for both components by applying the spectral similarity method. The exact relationship between the affected and excess IR spectrum is derived and the latter is discovered as the predictor of the band shifts in the affected spectrum. Owing to a reduced cancellation effect of intermolecular contributions, the affected spectrum is a physically justified counterpart of the excess IR spectrum, providing a complementary view of the interactions in the mixture.

  • Molecular mechanism of proton-coupled ligand translocation by the bacterial efflux pump EmrE
    • Jakub Jurasz
    • Maciej Bagiński
    • Jacek Czub
    • Miłosz Wieczór
    2021 Pełny tekst PLoS Computational Biology

    The current surge in bacterial multi-drug resistance (MDR) is one of the largest challenges to public health, threatening to render ineffective many therapies we rely on for treatment of serious infections. Understanding different factors that contribute to MDR is hence crucial from the global “one health” perspective. In this contribution, we focus on the prototypical broad-selectivity proton-coupled antiporter EmrE, one of the smallest known ligand transporters that confers resistance to aromatic cations in a number of clinically relevant species. As an asymmetric homodimer undergoing an “alternating access” protomer-swap conformational change, it serves as a model for the mechanistic understanding of more complex drug transporters. Here, we present a free energy and solvent accessibility analysis that indicates the presence of two complementary ligand translocation pathways that remain operative in a broad range of conditions. Our simulations show a previously undescribed desolvated apo state and anticorrelated accessibility in the ligand-bound state, explaining on a structural level why EmrE does not disrupt the pH gradient through futile proton transfer. By comparing the behavior of a number of model charged and/or aromatic ligands, we also explain the origin of selectivity of EmrE towards a broad class of aromatic cations. Finally, we explore unbiased pathways of ligand entry and exit to identify correlated structural changes implicated in ligand binding and release, as well as characterize key intermediates of occupancy changes.

  • Molecular targets for antifungals in amino acid and protein biosynthetic pathways
    • Aleksandra Kuplińska
    • Kamila Rząd
    2021 Pełny tekst AMINO ACIDS

    Fungi cause death of over 1.5 million people every year, while cutaneous mycoses are among the most common infections in the world. Mycoses vary greatly in severity, there are long-term skin (ringworm), nail or hair infections (tinea capitis), recurrent like vaginal candidiasis or severe, life-threatening systemic, multiorgan infections. In the last few years, increasing importance is attached to the health and economic problems caused by fungal pathogens. There is a growing need for improvement of the availability of antifungal drugs, decreasing their prices and reducing side effects. Searching for novel approaches in this respect, amino acid and protein biosynthesis pathways appear to be competitive. The route that leads from amino acid biosynthesis to protein folding and its activation is rich in enzymes that are descriptive of fungi. Blocking the action of those enzymes often leads to avirulence or growth inhibition. In this review, we want to trace the principal processes of fungi vitality. We present the data of genes encoding enzymes involved in amino acid and protein biosynthesis, potential molecular targets in antifungal chemotherapy, and describe the impact of inhibitors on fungal organisms.

  • Molecular Umbrella as A Nanocarrier for Antifungals
    • Andrzej Skwarecki
    • Dorota Martynow
    • Maria Milewska
    • Sławomir Milewski
    2021 Pełny tekst MOLECULES

    A molecular umbrella composed of two O‐sulfated cholic acid residues was applied for the construction of conjugates with cispentacin, containing a “trimethyl lock” (TML) or o‐dithiobenzylcarbamoyl moiety as a cleavable linker. Three out of five conjugates demonstrated antifungal in vitro activity against C. albicans and C. glabrata but not against C. krusei, with MIC90 values in the 0.22–0.99 mM range and were not hemolytic. Antifungal activity of the most active conjugate 24c, containing the TML–pimelate linker, was comparable to that of intact cispentacin. A structural analogue of 24c, containing the Nap‐NH2 fluorescent probe, was accumulated in Candida cells, and TML‐containing conjugates were cleaved in cell‐free extract of C. albicans cells. These results suggest that a molecular umbrella can be successfully applied as a nanocarrier for the construction of cleavable antifungal conjugates.

  • Molecularly targeted nanoparticles: an emerging tool for evaluation of expression of the receptor for advanced glycation end products in a murine model of peripheral artery disease
    • Marcin Woźniak
    • Christian J. Konopka
    • Agata Płoska
    • Jamila Hendhli
    • Anna Siekierzycka
    • Maciej Banach
    • Rafal Bartoszewski
    • Lawrence W. Dobrucki
    • Leszek Kalinowski
    • Iwona T. Dobrucki
    2021 Pełny tekst CELLULAR AND MOLECULAR BIOLOGY

    Abstract Background: Molecular imaging with molecularly targeted probes is a powerful tool for studying the spatio-temporal interactions between complex biological processes. The pivotal role of the receptor for advanced glycation end products (RAGE) in numerous pathological processes, aroused the demand for RAGE targeted imaging in various diseases. In the study, we evaluated the use of a diagnostic imaging agent for RAGE quantification in an animal model of peripheral artery disease, a multimodal dual-labeled probe targeted at RAGE (MMIA-CML). Methods: PAMAM dendrimer was conjugated with Nε-carboxymethyl-lysine (CML) modified albumin to synthesize the RAGE-targeted probe. A control untargeted agent carried native non-modified human albumin (HSA). Bifunctional p-SCN-Bn-NOTA was used to conjugate the 64Cu radioisotope. Surgical right femoral artery ligation was performed on C57BL/6 male mice. One week after femoral artery ligation, mice were injected with MMIA-CML or MMIA-HSA labeled with 64Cu radioisotope and 60 min later in vivo microPET-CT imaging was performed. Immediately after PET imaging studies, the murine hindlimb muscle tissues were excised and prepared for gene and protein expression analysis, using RT-PCR and Western blot technique respectively. To visualize RAGE expression in excised tissues, microscopic fluorescence imaging was performed using RAGE-specific antibodies and RAGE-targeted and -control MMIA. Results: Animals subjected to PET imaging exhibited greater MMIA-CML uptake in ischemic hindlimbs than non-ischemic hindlimbs. We observed a high correlation between fluorescent signal detection and radioactivity measurement. Significant RAGE gene and protein overexpression were observed in ischemic hindlimbs compared to non-ischemic hindlimbs at one week after surgical ligation. Fluorescence microscopic staining revealed significantly increased uptake of RAGE-targeted nanoparticles in both ischemic and non-ischemic muscle tissues compared to the control probe but at a higher level in ischemic hindlimbs. Ischemic tissue exhibited explicit RAGE dyeing following anti-RAGE antibody and high colocalization with the MMIA-CML targeted at RAGE. Conclusions: The present results indicate increased expression of RAGE in the ischemic hindlimb and enable the use of multimodal nanoparticles in both in vitro and in vivo experimental models, creating the possibility for imaging structural and functional changes with a RAGE-targeted tracer.

  • Molybdenum-uranium-vanadium geochemistry in the lower Paleozoic Alum Shale of Scandinavia: Implications for vanadium exploration
    • Leibo Bian
    • Niels H. Schovsbo
    • Anthony Chappaz
    • Xiaowei Zheng
    • Arne Thorshøj Nielsen
    • Thomas Ulrich
    • Xibo Wang
    • Shifeng Dai
    • Jennifer M. Galloway
    • Aleksandra Małachowska
    • Xuhui Xu
    • Hamed Sanei
    2021 INTERNATIONAL JOURNAL OF COAL GEOLOGY

    This paper investigates the hyper-enrichments of molybdenum (Mo), uranium (U), and vanadium (V) in the lower Paleozoic, Alum Shale of Denmark, Sweden, Norway, and Estonia. Molybdenum and U are mainly associated with organic matter and the highest contents are found in the Furongian part of the Alum Shale. This Furongian hyper-enrichment of Mo and U commenced with the Steptoean Positive Carbon Isotope Excursion (SPICE) event. The temporal distribution of V content increases moderately from the Miaolingian to the Furongian, followed by a significant increase in the Early Ordovician. In addition, the vanadium content generally increases towards the offshore, distal part of the Alum Shale basin. The geochemical affinity of V seems to change from organic matter in the Cambrian to minerals in the Early Ordovician. The hyper-enrichment of V in the Lower Ordovician succession appears to result from upwelling of deep oceanic water. The spatial distribution of V in the Alum Shale indicates that the highest concentrations are located in Scania, southernmost Sweden.

  • Monitoring of Caged Bluefin Tuna Reactions to Ship and Offshore Wind Farm Operational Noises
    • Vicente Puig-Pons
    • Ester Soliveres
    • Isabel Pérez-Arjona
    • Victor Espinosa
    • Pedro Poveda-Martínez
    • Jaime Ramis-Soriano
    • Patricia Ordoñez-Cebrián
    • Marek Moszyński
    • Fernando de la Gándara
    • Manuel Bou-Cabo
    • José L. Cort
    • Eladio Santaella
    2021 Pełny tekst SENSORS

    Underwater noise has been identified as a relevant pollution affecting marine ecosystems in different ways. Despite the numerous studies performed over the last few decades regarding the adverse effect of underwater noise on marine life, a lack of knowledge and methodological procedures still exists, and results are often tentative or qualitative. A monitoring methodology for the behavioral response of bluefin tuna (Thunnus thynnus) when exposed to ship and wind turbine operational noises was implemented and tested in a fixed commercial tuna feeding cage in the Mediterranean sea. Fish behavior was continuously monitored, combining synchronized echosounder and video recording systems. Automatic information extracted from acoustical echograms was used to describe tuna reaction to noise in terms of average depth and vertical dimensions of the school and the indicators of swimming speed and tilt direction. Video recordings allowed us to detect changes in swimming patterns. Different kinds of stimuli were considered during bluefin tuna cage monitoring, such as noise generated by feeding boats, wind farm operational noise, and other synthetic signals projected in the medium using a broadband underwater projector. The monitoring system design was revealed as a successful methodological approach to record and quantify reactions to noise. The obtained results suggested that the observed reactions presented a strong relationship with insonification pressure level and time. Behavioral changes associated with noise are difficult to observe, especially in semi-free conditions; thus, the presented approach offered the opportunity to link anthropogenic activity with possible effects on a given marine species, suggesting the possibility of achieving a more realistic framework to assess the impacts of underwater noise on marine animals.

  • Monitoring Regenerative Heat Exchanger in Steam Power Plant by Making Use of the Recurrent Neural Network
    • Tacjana Niksa-Rynkiewicz
    • Natalia Szewczuk-Krypa
    • Anna Witkowska
    • Krzysztof Cpałka
    • Marcin Zalasiński
    • Andrzej Cader
    2021 Pełny tekst Journal of Artificial Intelligence and Soft Computing Research

    Artificial Intelligence algorithms are being increasingly used in industrial applications. Their important function is to support operation of diagnostic systems. This paper pesents a new approach to the monitoring of a regenerative heat exchanger in a steam power plant, which is based on a specific use of the Recurrent Neural Network (RNN). The proposed approach was tested using real data. This approach can be easily adapted to similar monitoring applications of other industrial dynamic objects.

  • Monitoring the curing process of epoxy adhesive using ultrasound and Lamb wave dispersion curves
    • Erwin Wojtczak
    • Magdalena Rucka
    2021 Pełny tekst MECHANICAL SYSTEMS AND SIGNAL PROCESSING

    Monitoring the stiffness of adhesives is a crucial issue when considering the durability andstrength of adhesive joints. While there are many studies conducted on specimens madeonly from adhesive, the problem of curing of an adhesive film in real joints is moderatelyconsidered. This paper presents the monitoring of stiffening of epoxy adhesive using ultra-sound. Ultrasonic pulse velocity method was firstly applied for monitoring of adhesivespecimens. Then, a new procedure using dispersion relations and scanning laser vibrome-try was proposed for monitoring the curing process of an adhesive joint of steel plates. Bothapproaches gave comparable results showing the increase of the dynamic elastic modulusof adhesive in time. The study presented that the proposed procedure was capable of real-time monitoring the curing process of an adhesive layer in multi-layer systems.

  • Mono- and bimetallic (Pt/Cu) titanium(IV) oxide core–shell photocatalysts with UV/Vis light activity and magnetic separability
    • Zuzanna Bielan
    • Ewa Kowalska
    • Szymon Dudziak
    • Kunlei Wang
    • Bunsho Ohtani
    • Anna Zielińska-Jurek
    2021 Pełny tekst CATALYSIS TODAY

    Titanium(IV) oxide is one of the most widely investigated photocatalysts. However, separation of nano-sized particulate titania might result in profitless technologies for commercial applications. Additionally, bare titania is almost inactive under the Vis range of solar spectrum due to its wide bandgap. Therefore, the present study aims to prepare novel coreinterlayer- shell TiO2 magnetic photocatalysts modified with metal nanoparticles (Pt, Cu), which exhibit both photocatalytic and magnetic properties, making it easily separable within the magnetic field. Accordingly, the core-shell structure of Fe3O4@SiO2/TiO2 was obtained in water/TX100/cyclohexane microemulsion. Platinum and copper were photodeposited on four TiO2 templates and characterized by X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), specific surface area (BET) measurement and diffuse reflectance spectroscopy (DR-UV/Vis). Photoactivity was studied in the reaction of phenol, acetic acid, and methanol degradation under UV/Vis irradiation, using both polychromatic and monochromatic irradiation (action spectrum analysis). The core-interlayer-shell structure of Pt and Cu modified magnetic photocatalysts was confirmed using scanning transmission electron microscopy (STEM). Magnetic photocatalysts modified with platinum and copper revealed improved photoactivity both in oxidation and reduction photocatalytic reactions, as compared to unmodified Fe3O4@SiO2/TiO2 photocatalysts. Finally, the correlation between physicochemical properties and photocatalytic activities of Fe3O4@SiO2/TiO2-Pt/Cu photocatalysts was investigated. For the first time, the effect of metals’ loading on the efficiency of phenol degradation and mineralization (TOC removal), and quantum efficiency of reaction in the presence of magnetic photocatalysts were analyzed. It was found that phenol can be efficiently decomposed (ca. 100%) during 60 min of UV/Vis irradiation for the photocatalyst recovered within the magnetic field during three subsequent degradation cycles.

  • MONTE CARLO MODELING OF OPTICAL SENSOR FOR POST-OPERATIVE FREE FLAP MONITORING
    • Ignacy Rogoń
    • Piotr Tojza
    • Edmund Wittbrodt
    • Maciej Łuszczek
    • Jerzy Jankau
    2021

    After a preliminary study of the currently employed methods in vitality monitoring of the tissue flaps (TRAM, DIEP, SIEA), a usefulness of optical techniques is discussed. It seems that one of the most promising in monitoring tissue flaps blood flow is a near infrared spectrometry (NIRS). However, a special design of a measurement sensor has to be developed. First, basing on the literature study an optical “window” is characterized. Then, a Monte Carlo examination of the selected sensors constructions are evaluated. Also, design recommendations for a NIR measurement system are presented.

  • Monument / Las Szpęgawski
    • Joanna Kabrońska
    2021 Pełny tekst Architektura-Murator

    Współczesne monumenty często projektowane są tak, aby angażować uwagę odwiedzających miejsce pamięci nie tylko pod względem wizualnym. Zapraszają one do wejścia w swoją przestrzeń, nawet do dotknięcia powierzchni, a tym samym tworzą bliższe i bogatsze więzi ze zwiedzającymi. Tekst przedstawia Monument Pamięci w Lesie Szpęgawskim autorstwa Katarzyny Ephraim jako współczesne miejsce pamięci.

  • More than just a beer—the potential applications of by-products from beer manufacturing in polymer technology
    • Aleksander Hejna
    2021 Pełny tekst Emergent Materials

    Beer is the most popular alcoholic beverage in the world, and its popularity is continuously growing. Currently, global beer production is estimated at around 2 billion hectoliters. Nevertheless, the increasing production capacity implicates the rising issue of generated by-products—brewers’ spent grain, spent hops, spent yeast, and wastewater. They are generated in massive amounts, so having in mind the current pro-ecological trends, it is crucial to look for their utilization methods. Among the possibilities, particular attention should be drawn to polymer technology. This sector can efficiently use different lignocellulosic materials, which could be applied as fillers for polymer composites or sources of particular chemical compounds. Moreover, due to their chemical composition, brewing industry by-products may be used as functional fillers and additives. They could be introduced to enhance the materials’ resistance to oxidation, microbes, or fungi. These issues should be considered especially important in the case of biodegradable polymers, whose popularity is growing over the last years. This paper summarizes the literature reports related to the composition and potential applications of the brewing industry by-products in polymer technology. Moreover, potential directions of research based on the possibilities offered by the brewing industry by-products are presented.

  • Morphology Regulation Mechanism and Enhancement of Photocatalytic Performance of BiOX (X = Cl, Br, I) via Mannitol-Assisted Synthesis
    • Patrycja Wilczewska
    • Aleksandra Bielicka-giełdoń
    • Karol Szczodrowski
    • Anna Malankowska
    • Jacek Ryl
    • Karol Tabaka
    • Ewa Siedlecka
    2021 Pełny tekst Catalysts

    BiOX (X = Cl, Br, I) photocatalysts with dominant (110) facets were synthesized via a mannitol-assisted solvothermal method. This is the first report on the exposed (110) facets-, size-, and defects-controlled synthesis of BiOX achieved by solvothermal synthesis with mannitol. This polyol alcohol acted simultaneously as a solvent, capping agent, and/or soft template. The mannitol concentration on the new photocatalysts morphology and surface properties was investigated in detail. At the lowest concentration tested, mannitol acted as a structure-directing agent, causing unification of nanoparticles, while at higher concentrations, it functioned as a solvent and soft template. The effect of exposed (110) facet and surface defects (Bi(3−x)+, Bi4+, Bi5+) of BiOX on the photocatalytic activity of nanomaterials under the UV–Vis irradiation were evaluated by oxidation of Rhodamine B (RhB) and 5-fluorouracil (5-FU), an anticancer drug, and by reduction of Cr(VI). Additionally, the influence of crucial factors on the formation of BiOX in the synthesis with mannitol was discussed extensively, and the mechanism of BiOX formation was proposed. These studies presented a new simple method for synthesizing BiOX without any additional surfactants or shape control agents with good photocatalytic activity. The study also provided a better understanding of the effects of solvothermal conditions on the BiOX crystal growth.

  • Morphology, Thermo-Mechanical Properties and Biodegradibility of PCL/PLA Blends Reactively Compatibilized by Different Organic Peroxides
    • Marta Przybysz-Romatowska
    • Mateusz Barczewski
    • Szymon Mania
    • Agnieszka Tercjak
    • Józef Haponiuk
    • Krzysztof Formela
    2021 Pełny tekst Materials

    Reactive blending is a promising approach for the sustainable development of bio-based polymer blends and composites, which currently is gaining more and more attention. In this paper, biodegradable blends based on poly(ε-caprolactone) (PCL) and poly(lactic acid) (PLA) were prepared via reactive blending performed in an internal mixer. The PCL and PLA content varied in a ratio of 70/30 and 55/45. Reactive modification of PCL/PLA via liquid organic peroxides (OP) including 0.5 wt.% of tert-butyl cumyl peroxide (BU), 2,5-dimethyl-2,5-di-(tert-butylperoxy)-hexane (HX), and tert-butyl peroxybenzoate (PB) is reported. The materials were characterized by rotational rheometer, atomic force microscopy (AFM), thermogravimetry (TGA), differential scanning calorimetry (DSC), tensile tests and biodegradability tests. It was found that the application of peroxides improves the miscibility between PCL and PLA resulted in enhanced mechanical properties and more uniform morphology. Moreover, it was observed that the biodegradation rate of PCL/PLA blends reactively compatibilized was lower comparing to unmodified samples and strongly dependent on the blend ratio and peroxide structure. The presented results confirmed that reactive blending supported by organic peroxide is a promising approach for tailoring novel biodegradable polymeric systems with controllable biodegradation rates.

  • Możliwości i ryzyka związane z automatyzacją weryfikacji pracy studentów na przykładzie przedmiotu Metrologia
    • Sylwia Babicz-Kiewlicz
    • Dariusz Palmowski
    2021 Pełny tekst

    Przedmiot Metrologia jest wykładany na Wydziale Elektroniki, Telekomunikacji i Informatyki Politechniki Gdańskiej na trzecim semestrze studiów na trzech kierunkach: Elektronika i Telekomunikacja, Inżynieria Biomedyczna oraz Automatyka, Cybernetyka i Robotyka. W trakcie zajęć laboratoryjnych studenci wykonują sześć ćwiczeń, z których dwa są całkowicie oceniane przez program weryfikujący poprawność kolejnych wykonywanych zadań. Publikacja ma na celu przedstawienie zalet i wad oceniania automatycznego. Prezentuje możliwości, jakie niesie za sobą automatyzacja oceniania, jednocześnie wskazując wynikające z tego zagrożenia. Na finalną liczbę punktów możliwych do zdobycia na przedmiocie składają się: test, ocena pracy na zajęciach oraz sprawozdanie z każdego z sześciu ćwiczeń. O ile test oraz sprawozdanie są zawsze oceniane przez prowadzącego, o tyle ocena pracy na zajęciach na dwóch ćwiczeniach jest oceniana automatycznie przez program komputerowy. Co więcej, ocenianie to odbywa się w dwojaki sposób: na jednym ćwiczeniu punkty są przydzielane za poprawne wykonanie zadania, a na drugim ćwiczeniu każdorazowa pomyłka powoduje odjęcie 20% pozostałych możliwych do zdobycia punktów za dane zadanie. Wprowadzenie automatycznego oceniania zwalnia prowadzących z nieustannej kontroli studentów, dzięki czemu może on się skupić na zgłaszanych przez nich problemach. Jednocześnie nakłada na prowadzących obowiązek zapewnienia bezawaryjnego sprzętu. Z jednej strony takie ocenianie zapewnia pełen obiektywizm w postaci bezstronności prowadzącego, ale u studentów wywołuje poczucie ostateczności, co z kolei ich bardzo stresuje. Takich dylematów jest więcej. Autorzy w publikacji podjęli próbę analizy pozytywnych i negatywnych aspektów takiej formy oceny pracy na zajęciach.

  • Możliwości i zasady stosowania hybrydowych urządzeń energochłonnych na przykładzie urządzenia SafeEnd
    • Łukasz Jeliński
    • Kazimierz Jamroz
    • Marcin Budzyński
    • Anna Gobis
    • Dawid Bruski
    • Stanisław Burzyński
    • Grzegorz Bagiński
    2021 Drogownictwo

    Od kilku lat na świecie stosowane są urządzenia energochłonne spełniające rolę poduszki zderzeniowej oraz terminala energochłonnego. Urządzenia te stosowane są do osłony zakończeń barier drogowych oraz osłony obiektów znaj-dujących się w strefie bezpieczeństwa drogi. Przykładem takiego urządzenia jest urządzenie energochłonne U-15a SafeEnd (SE) stosowane od niedawna w Polsce, jednakże niektórzy zarządcy dróg zgłaszają obawy do ich stosowania, jako osłony energochłonnej. Największe zastrzeżenia wśród niektórych zarządzających drogami budziły: brak certyfikatu dla systemu SE, jako poduszki zderzeniowej, zbyt mała wielkość powierzchni czołowej (odblaskowej) sposób połączenia SE z barierami na rozjazdach, wymuszający większe odgięcie drogowych barier ochronnych od krawędzi jezdni, generując w ten sposób ryzyko uderzenia w barierę pod kątem przekraczającym 20 stopni, co może zwiększać ryzyko przerwania bariery i najazdu na przeszkodę. W niniejszym artykule zaprezentowano wyniki badań i analiz funkcjonowania urządzenia SE produkcji firmy Saferoad oraz możliwości i zasady stosowania tych urządzeń, jako hybrydowych urządzeń energochłonnych.

  • Możliwości zamiany elektrycznych przepływomierzy powietrza stosowanych w silnikach spalinowych samochodów
    • Robert Otta
    • Dariusz Świsulski
    • Anna Golijanek-Jędrzejczyk
    2021 Pełny tekst Przegląd Elektrotechniczny

    W artykule przedstawiono podstawowe typy przepływomierzy powietrza, stosowane w silnikach spalinowych samochodów: z klapąspiętrzającą, HLM, HFM, Vortex i MAP. Przedstawiono wyniki badania tych przepływomierzy na specjalnie przygotowanym stanowisku pomiarowym. Przeanalizowano możliwość ich zamiany i zweryfikowano taką możliwość w praktyce.

  • MRAS-Based Switching Linear Feedback Strategy for Sensorless Speed Control of Induction Motor Drives
    • Mohamed Amine Fnaiech
    • Jarosław Guziński
    • Mohamed Trabelsi
    • Abdellah Kouzou
    • Mohamed Benbouzid
    • Krzysztof Łuksza
    2021 Pełny tekst ENERGIES

    This paper presents a newly designed switching linear feedback structure of sliding mode control (SLF-SMC) plugged with an model reference adaptive system (MRAS) based sensorless fieldoriented control (SFOC) for induction motor (IM). Indeed, the performance of the MRAS depends mainly on the operating point and the parametric variation of the IM. Hence, the sliding mode control (SMC) could be considered a good control alternative due to its easy implementation and robustness. Simulation and experimentation results are presented to show the superiority of the proposed SLF-SMC technique in comparison with the classical PI controller under different speed ranges and inertia conditions.