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  • Formation of the hollow nanopillar arrays through the laser-induced transformation of TiO2 nanotubes
    • Jakub Wawrzyniak
    • Jakub Karczewski
    • Piotr Kupracz
    • Katarzyna Grochowska
    • Emerson Coy
    • Adam Mazikowski
    • Jacek Ryl
    • Siuzdak Katarzyna
    2020 Pełny tekst Scientific Reports

    In the following article, we present a simple, two-step method of creating spaced, hollow nanopillars, from the titania nanotube arrays via pulsed laser-treatment. Due to the high ordering of the structure, the prepared material exhibits photonic properties, which has been shown to increase the overall photoefficiency. The optical and morphological changes in the titania nanotubes after pulsed laser-treatment with 532, 355, and 266 nm wavelengths in the 10–50 mJ/cm2 fluence range are studied. The investigation reveals, that by using appropriate wavelength and energy, the number of surface defects, geometrical features, or both can be tailored.

  • Fotodachówka z systemem chłodzenia jako hybrydowy panel fotowoltaiczny – badania eksperymentalne
    • Jan Wajs
    • Aleksandra Gołąbek
    2020

    Panel fotowoltaiczny w formie dachówki, zbudowany z monokrystalicznych ogniw krzemowych, może tworzyć system solarny dla budownictwa, określany jako technologia Building-Integrated Photovoltaic (BIPV). Ze względu na spadek sprawności elektrycznej ogniw fotowoltaicznych wraz ze wzrostem temperatury pracy, poszukuje się metod ich skutecznego chłodzenia. Pozyskane w ten sposób ciepło można dodatkowo wykorzystać w innych procesach, np. dla potrzeb budownictwa mieszkaniowego lub budownictwa użyteczności publicznej. W artykule przedstawiono wyniki własnych badań z udziałem fotowoltaicznej dachówki chłodzonej powietrzem, stanowiącej hybrydowy panel fotowoltaiczny. Zaprezentowano stanowisko badawcze, wyposażone w symulator promieniowania słonecznego, oraz metodykę prowadzenia badań eksperymentalnych. Dokonano oceny wpływu warunków chłodzenia na temperaturę pracy dachówki oraz jej parametry elektryczne. W zakresie badań cieplnych, oszacowano gęstość pozyskanego strumienia ciepła, przy wydatkach objętościowych powietrza 1 i 4 m3/h, przepływającego w kanałach o wysokości 25 oraz 51 mm. Chłodzenie panelu fotowoltaicznego skutkowało maksymalnym wzrostem sprawności elektrycznej o 12,6%, a uzyskana całkowita sprawność konwersji promieniowania przekroczyła 32%.

  • fotografia pt. 'relacje nadzwyczajne'
    • Agnieszka Kurkowska
    2020

    Pandemia wymusiła relacje nadzwyczajne. Międzyludzkie i ludzko-przyrodnicze. Fotografia dokumentuje cykl instalacji artystycznych w przestrzeni lasu. Bohaterami dokumentowanych fotograficzne sytuacji są schematyczne zarysowane postaci ludzkie, w niecodziennej skali, niecodziennych ulokowaniach ale codziennych 'ułożeniach'. To czyni te relacje nadzwyczajnymi, choć pandemiczny kontekst społecznej izolacji ujmuje im semantyczny wydźwięk świąteczny. Utęskniona relacja z przyrodą paradoksalnie czyni te wykreowane spotkania wyjątkowymi.

  • FPGA Based Real Time Simulations of the Face Milling Process
    • Michał Mazur
    • Marek Galewski
    • Krzysztof Kaliński
    2020 Pełny tekst IEEE Access

    The article presents a successful implementation of the milling process simulation at the Field-Programmable Gate Array (FPGA). By using FPGA, very rigorous Real-Time (RT) simulation requirements can be met. The response time of the FPGA simulations is significantly reduced, and the time synchronization is better than in a typical RT system implemented in software. The FPGA-based approach is characterized by enormous flexibility when it comes to input and output operations that can be implemented deterministically in RT. Complex simulation software has been implemented using the High Level Synthesis technique, which is a relatively easy and fast approach for FPGA programming without using complex Hardware Description Languages. The hardware functions are based on procedures written in high-level C programming language. The mathematical descriptions of simulations, results of computer simulations, Hardware-in-the-Loop Simulation experiments, and real experiments are presented. The approach presented in this paper can be used to simulate the dynamics of various mechatronic systems.

  • FPGA-Based System for Electromagnetic Interference Evaluation in Random Modulated DC/DC Converters
    • Hermes Loschi
    • Piotr Lezynski
    • Robert Smolenski
    • Douglas Nascimento
    • Wojciech Śleszyński
    2020 Pełny tekst ENERGIES

    Field-Programmable Gate Array (FPGA) provides the possibility to design new “electromagnetic compatibility (EMC) friendly” control techniques for power electronic converters. Such control techniques use pseudo-random modulators (RanM) to control the converter switches. However, some issues connected with the FPGA-based design of RanM, such as matching the range of fixed-point numbers, might be challenging. The modern programming tools, such as LabVIEW, may facilitate the design process, but there are still fixed-point operations and limitations in arithmetic operations. This paper presents the design insights on the FPGA-based EMC friendly control system for DC/DC converter. Probability density functions (PDF) are used to analyse and improve pseudo-random algorithms. The theoretical algorithms, hardware details and experimental results are presented and discussed in terms of conducted electromagnetic interference emission.

  • Framework for Integration Decentralized and Untrusted Multi-vendor IoMT Environments
    • Andrzej Sobecki
    • Julian Szymański
    • David Gil
    • Higinio Mora
    2020 Pełny tekst IEEE Access

    Lack of standardization is highly visible while we use historical data sets or compare our model with others that use IoMT devices from different vendors. The problem also concerns the trust in highly decentralized and anonymous environments where sensitive data are transferred through the Internet and then are analyzed by third-party companies. In our research we propose a standard that has been implemented in the form of framework that allows describing requirements for methods and platforms that collect, manage, share, and perform data analysis form the Internet of Medical Things in order to increase trust. Further, we can distinguish two types of IoMT devices: passive and active. Passive devices measure some parameters of the body and save them in databases. Active devices have the functionality of passive devices and moreover, they can act in a defined way, eg.: inject directly into the patient's body some elements such as a medicament, electric signals to the nervous system, stimulus pacemaker, etc. Nevertheless how to create a safe and transparent environment for using data active sensors, developing safe ML models, performing medical decisions based on the created models and finally deploy this decision to the specified device. While the IoMT devices are used in real-life, professional healthcare the control system should offer tools for backtracking decisions, allowing e.g. to find who made a mistake, or which event caused a particular decision. Our framework provides backtracking in the IoMT environment in which for each medical decision supported by ML models we can prove which sensor sends the data, which data was used to create prediction/recommendation, what prediction was produced, who and when use it, what medical decision was made by who. We propose a vendor transparency framework for each IoMT devices and ML models that will process the medical data in order to increase patient's privacy and prevent for eventual data leaking.

  • Framework for Structural Health Monitoring of Steel Bridges by Computer Vision
    • Adam Marchewka
    • Patryk Ziółkowski
    • Victor Aguilar-vidal
    2020 Pełny tekst SENSORS

    The monitoring of a structural condition of steel bridges is an important issue. Good condition of infrastructure facilities ensures the safety and economic well-being of society. At the same time, due to the continuous development, rising wealth of the society and socio-economic integration of countries, the number of infrastructural objects is growing. Therefore, there is a need to introduce an easy-to-use and relatively low-cost method of bridge diagnostics. We can achieve these benefits by the use of Unmanned Aerial Vehicle-Based Remote Sensing and Digital Image Processing. In our study, we present a state-of-the-art framework for Structural Health Monitoring of steel bridges that involves literature review on steel bridges health monitoring, drone route planning, image acquisition, identification of visual markers that may indicate a poor condition of the structure and determining the scope of applicability. The presented framework of image processing procedure is suitable for diagnostics of steel truss riveted bridges. In our considerations, we used photographic documentation of the Fitzpatrick Bridge located in Tallassee, Alabama, USA.

  • Free Vibration of Flexomagnetic Nanostructured Tubes Based on Stress-driven Nonlocal Elasticity
    • Mohammad Malikan
    • Victor Eremeev
    2020 Pełny tekst

    A framework for the flexomagneticity influence is here considered extending the studies about this aspect on the small scale actuators. The developed model accommodates and composes linear Lagrangian strains, Euler-Bernoulli beam approach as well as an extended case of Hamilton’s principle. The nanostructured tube should subsume and incorporate size effect; however, for the sake of avoiding the staggering costs of experiments, here, via stress-driven nonlocal elasticity theory, the desired influence is captured. A given section is dedicated to reveal the accuracy of the achieved model. In view of solution, the numerical results are generated analytically. We receive the conclusion that in nanoscale tubes the diameter can affect fundamentally the performance of the flexomagnetic effect.

  • Frequency Diagnostics of Transformer Insulating Parameters
    • Peter Brnacal
    • Miroslav Gutten
    • Cefer Viktor
    • Daniel Korenciak
    • Leszek Jarzębowicz
    2020

    In the article is presented experimental analysis and diagnostics of insulating system oil-paper for power transformers, mainly by progressive frequency method – dielectric spectroscopy. In the 1-st part of the article is described base theory about measurement and diagnostics insulating part (oil and paper) of power transformers. In the 2-nd part of article is described measuring method of insulating frequency diagnostics - frequency domain spectroscopy (FDS). This method is used for analysis insulating condition of highvoltage equipment with insulating oil-paper. In the 3-st part of article is described measuring time method of insulating diagnostics - return voltage measurement (RVM). This method is used for analysis of condition of paper moisture of high-voltage equipment. The both measuring methods are unique in terms of analysis of insulating system of oil power transformers. In comparison with other methods, the RVM and FDS methods it is possible comparison and evaluate the moisture state of the dielectric paper of the power transformer with high reliability and accurate. Their reliability in determining moisture in paper was shown by determining the same result (3.5%) on the same measured distribution transformer.

  • Functional phase bistability in a nanocrystalline RbMn[Fe(CN)6] thin film fabricated by matrix-assisted laser evaporation
    • Dominik Maskowicz
    • Mirosław Sawczak
    • Rafał Jendrzejewski
    • Maria Gazda
    • Hiroko Tokoro
    • Shin-ichi Ohkoshi
    • Yann Garcia
    • Gerard Śliwiński
    2020 SCRIPTA MATERIALIA

    One of the main barriers hindering applications of Prussian blue metal assemblies is their poor processability, which makes the fabrication of intact thin films very difficult. In this work, a nanocrystalline RbMn[Fe(CN)6]·xH2O film on silicon substrate was obtained for the first time via laser-stimulated deposition and investigated. Temperature-induced phase transition and bistability within broad hysteresis loop (120 K), along with transition temperatures up to 317 K, which is the highest in the RbMnFe series, were observed using variable-temperature Raman spectroscopy. This study thus proposes a reliable deposition approach for preparing a functional magnetic materials that operate at room temperature.

  • Fundamental properties of solutions to fractional-order Maxwell's equations
    • Tomasz Stefański
    • Jacek Gulgowski
    2020 JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS

    In this paper, fundamental properties of solutions to fractional-order (FO) Maxwell's equations are analysed. As a starting point, FO Maxwell's equations are introduced in both time and frequency domains. Then, we introduce and prove the fundamental properties of electromagnetic field in FO electromagnetics, i.e. energy conservation, uniqueness of solutions, and reciprocity. Furthermore, the algorithm of the plane wave simulation is developed and implemented in software, which allows us to demonstrate the general properties of electromagnetic field in the media described by FO models (FOMs). The differences in interpretation of the fundamental theorems of electromagnetics (i.e. Poynting's theorem, the uniqueness theorem and the Lorentz reciprocity theorem) in comparison to integer-order electromagnetics are analysed. It is demonstrated that all the properties of electromagnetic field, related to these fundamental theorems are preserved when time derivatives are generalized towards FO in Maxwell's equations.

  • Fundamental Schemes to Determine Disjoint Paths for Multiple Failure Scenarios
    • Teresa Gomes
    • Luisa Jorge
    • Rita Girão-Silva
    • Jose Yallouz
    • Péter Babarczi
    • Jacek Rak
    2020

    Disjoint path routing approaches can be used to cope with multiple failure scenarios. This can be achieved using a set of k (k> 2) link- (or node-) disjoint path pairs (in single-cost and multi-cost networks). Alternatively, if Shared Risk Link Groups (SRLGs) information is available, the calculation of an SRLG-disjoint path pair (or of a set of such paths) can protect a connection against the joint failure of the set of links in any single SRLG. Paths traversing disaster-prone regions should be disjoint, but in safe regions it may be acceptable for the paths to share links or even nodes for a quicker recovery. Auxiliary algorithms for obtaining the shortest path from a source to a destination are also presented in detail, followed by the illustrated description of Bhandari’s and Suurballe’s algorithms for obtaining a pair of paths of minimal total additive cost. These algorithms are instrumental for some of the presented schemes to determine disjoint paths for multiple failure scenarios.

  • Fundamentals of Communication Networks Resilience to Disasters and Massive Disruptions
    • Jacek Rak
    • David Hutchison
    • Janos Tapolcai
    • Rasa Bruzgiene
    • Massimo Tornatore
    • Carmen Mas-Machuca
    • Marija Furdek
    • Paul Smith
    2020

    Communication networks are exposed to a variety of massive failure events following from activities of nature, weather-induced disruptions, technology-implied problems, and malicious human activities. In this chapter, we first highlight the characteristics of these scenarios and discuss example failure events reported during the last three decades. Next, we explain the concept of network resilience and present an overview of major problems and related schemes further addressed in this monograph, concerning (a) measures and models for the analysis and evaluation of disaster-resilient networks, (b) techniques for design and update of disaster-resilient systems, (c) algorithms and schemes for resilient systems, and (d) advanced topics focusing, e.g. on emerging communication technologies.

  • Fuzzy Control of Waves Generation in a Towing Tank
    • Marcin Drzewiecki
    • Jarosław Guziński
    2020 Pełny tekst ENERGIES

    This paper presents the results of research related to the transformation of electrical energy into potential and kinetic energy of waves generated on the water surface. The waves are generated to model the environmental conditions for the needs of the model tests. The model tests are performed on model-scale objects to predict the features of full-scale maritime objects. It is done to improve human safety and the survivability of constructions. Electrical energy is transformed into the energy of the water waves using a wave maker. The wave maker considered is a facility with an electrohydraulic drive and an actuator submerged into the water. The actuator movement results in the waves being mechanically-generated in accordance with the wave maker theory. The study aimed to investigate the advantage of the newly implemented fuzzy-logic controller over the hitherto cascading proportional-integral controllers of the wave maker actuator. The research was focused on experimental investigation of the transformation process outcomes harvested under the fuzzy-logic controller, versus the cascading proportional-integral controllers. The waves were generated and measured in the real towing tank, located in the Maritime Advanced Research Centre (CTO S.A.). The investigation confirmed the advantage of the fuzzy-logic controller. It provides more accurate transformation of energy into the desired form of the water waves of specified parameters—frequency and amplitude—and more flat amplitude-frequency characteristic of the transformation process.

  • Fuzzy Divisive Hierarchical Clustering of Solvents According to Their Experimentally and Theoretically Predicted Descriptors
    • Miroslava Nedyalkova
    • Costel Sarbu
    • Marek Tobiszewski
    • Vasil Simeonov
    2020 Pełny tekst Symmetry-Basel

    The present study describes a simple procedure to separate into patterns of similarity a large group of solvents, 259 in total, presented by 15 specific descriptors (experimentally found and theoretically predicted physicochemical parameters). Solvent data is usually characterized by its high variability, dierent molecular symmetry, and spatial orientation. Methods of chemometrics can usefully be used to extract and explore accurately the information contained in such data. In this order, advanced fuzzy divisive hierarchical-clustering methods were eciently applied in the present study of a large group of solvents using specific descriptors. The fuzzy divisive hierarchical associative-clustering algorithm provides not only a fuzzy partition of the solvents investigated, but also a fuzzy partition of descriptors considered. In this way, it is possible to identify the most specific descriptors (in terms of higher, smallest, or intermediate values) to each fuzzy partition (group) of solvents. Additionally, the partitioning performed could be interpreted with respect to the molecular symmetry. The chemometric approach used for this goal is fuzzy c-means method being a semi-supervised clustering procedure. The advantage of such a clustering process is the opportunity to achieve separation of the solvents into similarity patterns with a certain degree of membership of each solvent to a certain pattern, as well as to consider possible membership of the same object (solvent) in another cluster. Partitioning based on a hybrid approach of the theoretical molecular descriptors and experimentally obtained ones permits a more straightforward separation into groups of similarity and acceptable interpretation. It was shown that an important link between objects’ groups of similarity and similarity groups of variables is achieved. Ten classes of solvents are interpreted depending on their specific descriptors, as one of the classes includes a single object and could be interpreted as an outlier. Setting the results of this research into broader perspective, it has been shown that the fuzzy clustering approach provides a useful tool for partitioning by the variables related to the main physicochemical properties of the solvents. It gets possible to oer a simple guide for solvents recognition based on theoretically calculated or experimentally found descriptors related to the physicochemical properties of the solvents.

  • Fuzzy Multi-Regional Fractional PID controller for Pressurized Water nuclear Reactor
    • Bartosz Puchalski
    • Tomasz Rutkowski
    • Kazimierz Duzinkiewicz
    2020 Pełny tekst ISA TRANSACTIONS

    The paper presents the methodology for the synthesis of a Fuzzy Multi-Regional Fractional Order PID controller (FMR-FOPID) used to control the average thermal power of a PWR nuclear reactor in the load following mode. The controller utilizes a set of FOPID controllers and the fuzzy logic Takagi-Sugeno reasoning system. The proposed methodology is based on two optimization parts. The first part is devoted to finding the optimal parameters of local FOPID controllers and in the second part, the optimal membership functions of the fuzzy reasoning system are designed. During the controller designing and comparison phase, the two validated nodal models of a nuclear reactor are used, simplified model and extended model respectively. The proposed approach has been verified by computer simulations that confirm its effectiveness.

  • GaN Nanowire Array for Charge Transfer in Hybrid GaN/P3HT:PC71BM Photovoltaic Heterostructure Fabricated on Silicon
    • Giorgi Tchutchulashvili
    • Sergij Chusnutdinow
    • Wojciech Mech
    • Krzysztof P. Korona
    • Anna Reszka
    • Marta Sobanska
    • Zbigniew R. Zytkiewicz
    • Wojciech Sadowski
    2020 Pełny tekst Materials

    Abstract: We demonstrate that a GaN nanowire array can be used for efficient charge transfer between the organic photovoltaic layer and silicon in a Si/GaN/P3HT:PC71BM inverted hybrid heterostructure. The band alignment of such a material combination is favorable to facilitate exciton dissociation, carrier separation and electron transport into Si. The ordered nature of the GaN array helps to mitigate the intrinsic performance limitations of the organic active layer. The dependence of photovoltaic performance enhancement on the morphology of the nanostructure with nanowire diameters 30, 50, 60, 100 and 150 nm was studied in detail. The short circuit current was enhanced by a factor of 4.25, while an open circuit voltage increase by 0.32 volts was achieved compared to similar planar layers.

  • Gdańsk 2020
    • Krzysztof Wróblewski
    2020

    Na wystawie Gdańsk 2020 prezentujemy prace, które były odpowiedzią na sytuację, w jakiej znaleźli się artyści w obliczu zamrożenia działań kulturalnych, które są oddaniem emocji pierwszych tygodni izolacji. To komentarz do konkretnego czasu, ale też do sytuacji artystów i kryzysu, który przed nami, a także do sytuacji twórców w Polsce w ogóle – mówi Aleksandra Szymańska, dyrektorka Instytutu Kultury Miejskiej. Otwarcie wystawy online, która prezentuje 50 prac gdańskich artystów i artystek odbędzie się 3 czerwca o godz. 19.00 na Facebooku IKM-u oraz na portalu gdansk.pl. Prace będą dostępne na stronie www.gdansk2020.eu. Wernisaż wystawy odbędzie się online 3 czerwca o godz. 19.00 na Facebooku IKM-u: https://www.facebook.com/IKMgdansk/ oraz na www.gdansk.pl.

  • Gdańsk: a City of Solidarity and Freedom
    • Piotr Lorens
    • Izabela Mironowicz
    2020 disP

    Only a few cities can claim that they have changed Europe and indeed the World. Gdańsk is privileged to be one of them. It is not a “caprice of history” that the Solidarity movement which, in the end, got the iron curtain torn, was born in this particular place. It is a logical consequence of ten centuries of the collective wisdom of the people that built Gdańsk and the region of Pomerania. The tragic assassination of the Mayor of Gdańsk, Paweł Adamowicz, in 2019, reminds us that these values that city represents – solidarity and freedom – should be recaptured from those who want to push our cities towards other principles. Gdańsk is once again becoming a symbol of the choice we all have to face. Is the city ready to set sail towards a new destination in its stormy history?

  • Gdyński modernizm lat międzywojennych. Oblicze stylowe epoki = Modernism of the Interwar Period of Gdynia. A Picture of the Style of the Epoch
    • Maria Sołtysik
    2020

    Lata dwudzieste i trzydzieste XX wieku, a więc czas w którym Gdynia powstawała, nie są w historii architektury okresem homogenicznym. Stylistyka modernizmu lat międzywojennych - wbrew swym uniwersalistycznym założeniom ideowym - nosiła w sobie dużą różnorodność. Widzimy to zarówno w odniesieniu do Gdyni, jak i w ogóle do architektury europejskiej tego okresu. Niniejszy rozdział prezentuje cztery główne oblicza architektury modernistycznej Gdyni: wczesno modernistyczny nurt Art Déco, skrajnie awangardowy nurt funkcjonalizmu, luksusowy nurt streamline moderne oraz umiarkowanie modernistyczny nurt wertykalizmu.

  • Gender-Related Differences in Trimethylamine and Oxidative Blood Biomarkers in Cardiovascular Disease Patients
    • Laura Bordoni
    • Donatella Fedeli
    • Marco Piangerelli
    • Iwona Pelikant-Malecka
    • Adrianna Radulska
    • Joanna J. Samulak
    • Angelika K. Sawicka
    • Lukasz Lewicki
    • Leszek Kalinowski
    • Robert A. Olek
    • Rosita Gabbianelli
    2020 Pełny tekst Biomedicines

    Gender differences in the burden of cardiovascular disease (CVD) have been observed worldwide. In this study, plasmatic levels of trimethylamine (TMA) and blood oxidative biomarkers have been evaluated in 358 men (89 controls and 269 CVD patients) and 189 women (64 control and 125 CVD patients). The fluorescence technique was applied to determine erythrocyte membrane fluidity using 1,6-diphenyl-1,3,5-hexatriene (DPH) and Laurdan, while lipid hydroperoxides were assessed by diphenyl − 1-pyrenylphosphine (DPPP). Results show that levels of plasmatic TMA were higher in healthy men with respect to healthy women (p = 0.0001). Significantly lower TMA was observed in male CVD patients (0.609 ± 0.104 μM) compared to healthy male controls (0.680 ± 0.118 μ M) ( p < 0.001), while higher levels of TMA were measured in female CVD patients (0.595 ± 0.115 μ M) with respect to female controls (0.529 ± .073 μ M) ( p < 0.001). DPPP was significantly higher in healthy control men than in women (p < 0.001). Male CVD patients displayed a lower value of DPPP (2777 ± 1924) compared to healthy controls (5528 ± 2222) ( p < 0.001), while no significant changes were measured in females with or without CVD (p > 0.05). Membrane fluidity was significantly higher ( p < 0.001) in the hydrophobic bilayer only in control male subjects. In conclusion, gender differences were observed in blood oxidative biomarkers, and DPPP value might be suggested as a biomarker predictive of CVD only in men.

  • Generalized Gradient Equivariant Multivalued Maps, Approximation and Degree
    • Zdzisław Dzedzej
    • Tomasz Gzella
    2020 Pełny tekst Mathematics

    Consider the Euclidean space Rn with the orthogonal action of a compact Lie group G. We prove that a locally Lipschitz G-invariant mapping f from Rn to R can be uniformly approximated by G-invariant smooth mappings g in such a way that the gradient of g is a graph approximation of Clarke’s generalized gradient of f . This result enables a proper development of equivariant gradient degree theory for a class of set-valued gradient mappings

  • Generation and Characterization of a DNA-GCN4 Oligonucleotide-Peptide Conjugate: The Impact DNA/Protein Interactions on the Sensitization of DNA
    • Paweł Wityk
    • Rafał Piątek
    • Dorota Kostrzewa-Nowak
    • Robert Nowak
    2020 Pełny tekst MOLECULES

    Radiotherapy, the most common therapy for the treatment of solid tumors, exerts its effects by inducing DNA damage. To fully understand the extent and nature of this damage, DNA models that mimic the in vivo situation should be utilized. In a cellular context, genomic DNA constantly interacts with proteins and these interactions could influence both the primary radical processes (triggered by ionizing radiation) and secondary reactions, ultimately leading to DNA damage. However, this is seldom addressed in the literature. In this work, we propose a general approach to tackle these shortcomings. We synthesized a protein-DNA complex that more closely represents DNA in the physiological environment than oligonucleotides solution itself, while being sufficiently simple to permit further chemical analyses. Using click chemistry, we obtained an oligonucleotide-peptide conjugate, which, if annealed with the complementary oligonucleotide strand, forms a complex that mimics the specific interactions between the GCN4 protein and DNA. The covalent bond connecting the oligonucleotide and peptide constitutes a part of substituted triazole, which forms due to the click reaction between the short peptide corresponding to the specific amino acid sequence of GCN4 protein (yeast transcription factor) and a DNA fragment that is recognized by the protein. DNAse footprinting demonstrated that the part of the DNA fragment that specifically interacts with the peptide in the complex is protected from DNAse activity. Moreover, the thermodynamic characteristics obtained using differential scanning calorimetry (DSC) are consistent with the interaction energies calculated at the level of metadynamics. Thus, we present an efficient approach to generate a well-defined DNA-peptide conjugate that mimics a real DNA-peptide complex. These complexes can be used to investigate DNA damage under conditions very similar to those present in the cell.

  • Generic invariant measures for iterated systems of interval homeomorphisms
    • Wojciech Czernous
    • Tomasz Szarek
    2020 Pełny tekst ARCHIV DER MATHEMATIK

    It is well known that iterated function systems generated by orientation preserving homeomorphisms of the unit interval with positive Lyapunov exponents at its ends admit a unique invariant measure on (0, 1) provided their action is minimal. With the additional requirement of continuous differentiability of maps on a fixed neighbourhood of {0,1} { 0 , 1 } , we present a metric in the space of such systems which renders it complete. Using then a classical argument (and an alternative uniqueness proof), we show that almost singular invariant measures are admitted by systems lying densely in the space. This allows us to construct a residual set of systems with unique singular stationary distribution. Dichotomy between singular and absolutely continuous unique measures is assured by taking a subspace of systems with absolutely continuous maps; the closure of this subspace is where the residual set is found.

  • Genetic Algorithm Approach for Gains Selection of Induction Machine Extended Speed Observer
    • Daniel Wachowiak
    2020 Pełny tekst ENERGIES

    The subject of this paper is gains selection of an extended induction machine speed observer. A high number of gains makes manual gains selection difficult and due to nonlinear equations of the observer, well-known methods of gains selection for linear systems cannot be applied. A method based on genetic algorithms has been proposed instead. Such an approach requires multiple fitness function calls; therefore, using a quality index based on simulations makes gains selection a time-consuming process. To find a fitness function that evaluates, in a short time, quality indices based on poles placement have been proposed. As the observer is nonlinear, equations describing the observer dynamics have been linearized. The relationship between poles placement and real dynamic properties has been shown. A series of studies has been performed to investigate the influence of the operating point of the machine on the dynamics of the observer. It has been proven that rotor speed has a significant impact on the placement of the poles and the observer may lose stability after a rotation direction change. A method of gains modification to maintain symmetrical properties of the observer for both directions has been presented. Experimental studies of the observer during machine reverse in the open and closed-loop control system have been performed. The results show that the observer can be implemented in a sensorless drive, using the proposed gains selection method.

  • Genetic and Epigenetic Aspects of Atopic Dermatitis
    • Bogusław Nedoszytko
    • Edyta Reszka
    • Danuta Gutowska-Owsiak
    • Magdalena Trzeciak
    • Magdalena Lange
    • Justyna Jarczak
    • Marek Niedoszytko
    • Ewa Jablonska
    • Jan Romantowski
    • Dominik Strapagiel
    • Jarosław Skokowski
    • Anna Siekierzycka
    • Roman J. Nowicki
    • Iwona T. Dobrucki
    • Anna Zaryczańska
    • Leszek Kalinowski
    2020 Pełny tekst INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    Atopic dermatitis is a heterogeneous disease, in which the pathogenesis is associated with mutations in genes encoding epidermal structural proteins, barrier enzymes, and their inhibitors; the role of genes regulating innate and adaptive immune responses and environmental factors inducing the disease is also noted. Recent studies point to the key role of epigenetic changes in the development of the disease. Epigenetic modifications are mainly mediated by DNA methylation, histone acetylation, and the action of specific non-coding RNAs. It has been documented that the profile of epigenetic changes in patients with atopic dermatitis (AD) di ff ers from that observed in healthy people. This applies to the genes a ff ecting the regulation of immune response and inflammatory processes, e.g., both a ff ecting Th1 bias and promoting Th2 responses and the genes of innate immunity, as well as those encoding the structural proteins of the epidermis. Understanding of the epigenetic alterations is therefore pivotal to both create new molecular classifications of atopic dermatitis and to enable the development of personalized treatment strategies.

  • Geographical and chronological knowledge in teaching the history of architecture
    • Aleksander Piwek
    • Tomasz Jażdżewski
    • Piotr Samól
    2020 Pełny tekst World Transactions on Engineering and Technology Education

    The subject of this article is the analysis of examination results from the course, the History of Polish Architecture. These Bachelor studies present the political, economic and cultural issues of medieval and early modern architecture, and their changes over time. Basic knowledge of the administrative division and historical regions is needed for a proper understanding of the regional diversity of cultural heritage monuments in Poland. One of the tasks of the final test is to identify from pictures ten historic buildings and to provide the name, function, time of creation, architectural style, author, city and region of the pictures. Analysis of the answers shows that many students, despite their good knowledge of architecture, have problems with the correct location of not only small- and medium-sized cities, but also the largest cities and the capital. Another issue discussed in this article is the problem of students recognising architectural styles and the time of their occurrence in various regions.

  • GEOINFORMATYCZNE NARZĘDZIE DO BADANIA ZASIĘGU LOKALNYCH STACJI NADAWCZYCH RADIOFONII CYFROWEJ DAB+
    • Przemysław Falkowski-Gilski
    • Ryszard J. Zieliński
    • Marek Kulawiak
    • Marcin Kulawiak
    2020 Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

    Kwestia zapewnienia odpowiedniego pokrycia sygnałem multipleksu jest kluczowym aspektem zarówno dla nadawców publicznych jak i prywatnych, a w szczególności lokalnych stacji zainteresowanych procesem cyfryzacji. W pracy przedstawiono geoinformatyczne narzędzie, umożliwiające badanie zasięgu lokalnych stacji nadawczych radiofonii cyfrowej DAB+. Analizę przeprowadzono dla pionierskiej w Polsce stacji LocalDAB we Wrocławiu. Wyniki opisanych prac mogą być pomocne dla naukowców i profesjonalistów działających we wspomnianej dziedzinie.

  • Geokompozyty drenażowe w odwodnieniach drogowych i kolejowych
    • Remigiusz Duszyński
    2020 Magazyn Autostrady

    Zagadnienie zagospodarowania wód opadowych i gruntowych w rejonie konstrukcji drogowych i kolejowych stanowi istotny element bezpiecznej i efektywnej eksploatacji tych obiektów. Odpowiednie wykorzystanie geokompozytów drenażowych zapewnia bezproblemową pracę konstrukcji oraz właściwą ochronę przed uszkodzeniami wynikającymi z niekontrolowanego oddziaływania wody.

  • Geometry of cycling track
    • Maciej Solarczyk
    2020 Pełny tekst Budownictwo i Architektura

    The paper describes the problems related to shaping of the geometry of the cycling track. The method of selection of the angle at the track curve is presented. Issues related to the selection of the appropriate transition curve and the superelevation section along the transition curve are presented. Reference to the recommendations presented in the literature and scientific papers has been made. Special attention to the need of consideration of the subjective feelings of the cyclist is paid. The paper describes the guidelines of the International Cycling Union (UCI) on shaping the geometry of the cycling track.

  • Geospatial Coverage and Signal Quality Measurements of Terrestrial DAB+ Network in Northern Poland
    • Przemysław Falkowski-Gilski
    • Marek Kulawiak
    • Marcin Kulawiak
    2020

    Modern signal coverage maps are prepared based on industry-standard radio propagation models, which take into account a number of parameters, including: type of antenna, distance from the transmitter, type of terrain, etc. However, such simulations are prone to location-specific inaccuracies, and should be verified with in-situ measurements. This paper presents results of a field test of a terrestrial DAB+ (Digital Audio Broadcasting plus) network in the metropolitan area of the Tricity, the largest agglomeration in Northern Poland. Obtained results were compared to previously generated radio signal coverage maps. The study shown that terrain topology has a profound impact on signal strength, and should be more accurately implemented in coverage modeling, particularly in order to provide a stable and reliable high-quality connection.

  • Geosyntetyki w funkcji zbrojenia
    • Angelika Duszyńska
    2020 Geoinżynieria, Drogi, Mosty, Tunele

    Wymiarowanie geosyntetyków pełniących funkcję zbrojenia gruntu nasypowego polega na dobraniu wyrobów spełniających stosowne warunki stateczności zewnętrznej i wewnętrznej konstrukcji, które zagwarantują zachowanie integralności konstrukcji i bezpieczną współpracę zbrojenia oraz gruntu w projektowanym okresie użytkowalności. Prawidłowe zaprojektowanie budowli ziemnej zbrojonej geosyntetykami wymaga szczegółowych i rzetelnych danych dotyczących zbrojenia. Należą do nich przede wszystkim: - wytrzymałość geosyntetyku na rozciąganie z uwzględnieniem pełzania w projektowym okresie użytkowania, - wpływ uszkodzeń w trakcie wbudowania zbrojenia i zagęszczania gruntu (kruszywa), - wpływ oddziaływań środowiskowych itp.

  • GIUSEPPE VOLPI. IL GRANDE MEDIATORE TRA ISTITUZIONI, POLITICA ED ECONOMIA
    • Luciano Segreto
    2020 Studi Storici

    Giuseppe Volpi di Misurata represented a mediation point between different interests both in the economic field and in the complex national – but also regional and local – political balance that long underpinned the fascist regime. This article intends to revisit this figure between the 1920s and the Second World War. The attempt will be made to identify, through an approach that will be chronological and thematic, the passages that led Volpi to embody the ideal prototype of the mediator between different economic and political interests. In his relationship with the institutions and with the fascist government the paper will identify the elements that made him – to the eyes of many, in Italy as well as abroad – a potential successor to Mussolini in the event of a regime crisis.

  • Global Optimization for Recovery of Clipped Signals Corrupted With Poisson-Gaussian Noise
    • Arthur Marmin
    • Anna Węsierska
    • Marc Castella
    • Jean-Christophe Pesquet
    2020 IEEE SIGNAL PROCESSING LETTERS

    We study a variational formulation for reconstructing nonlinearly distorted signals corrupted with a Poisson-Gaussian noise. In this situation, the data fidelity term consists of a sum of a weighted least squares term and a logarithmic one. Both of them are precomposed by a nonlinearity, modelling a clipping effect, which is assumed to be rational. A regularization term, being a piecewise rational approximation of the ℓ0 function provides a suitable sparsity measure with respect to a preset linear operator. We propose a global optimization approach for such a problem. More specifically, it is first transformed into a generalized moment problem by introducing some auxiliary variables. Then, a hierarchy of semidefinite programming relaxations is built. Numerical examples show the good performance of the proposed approach.

  • Golden artefacts, resin figurines, body adhesives and tomb sediments from the pre-Columbian burial site El Caño (Gran Coclé, Panamá): tracing organic contents using molecular archaeometry
    • Joeri Kaal
    • María Martín Seijo
    • César Oliveira
    • Ewa Wagner-Wysiecka
    • Victoria E. McCoy
    • Mónica M. Solórzano Kraemer
    • Alexander Kerner
    • Philip Wenig
    • Carlos Mayo
    • Julia Mayo
    2020 Pełny tekst Journal of Archaeological Science

    This research aimed to determine the origin of organic residues from funerary contexts in the El Ca~no settlement (Gran Cocl�e area, Panam�a, Central America) by means of multiple molecular probing techniques (GC-MS of organic solvent extracts and pyrolysis-GC-MS, THM-GC-MS and FTIR of solid samples). The samples include particles of precious resin figurines, fillings of golden objects, tomb sediments, plant exudates from extant plants (reference collection) and other reference materials (amber). The labdane diterpene fingerprints (eperuic, isoozic, copalic and kolavenic acids and derivatives) of the resin figurines, a resinous bead and several other samples, suggest that they were composed primarily of Hymenaea resin. Besides traditional interpretation approaches (visual comparison of chromatograms and relative proportions data), we used a novel OpenChrom® application that resolves complex pyrolysis chromatograms by screening data from archaeological samples for marker products defined on the basis of a reference collection (ChromIdent). ChromIdent confirmed the Hymenaea origin of many samples and also Burseraceae resin was identified in some samples, which is present as a minor ingredient in resin figurines (indicative of mixing practices) and as the dominant resin in tomb sediment that had been in contact with the corpses (indicating balsaming practices). The degree of polymerization of the Hymenaea resin was higher than for extant resin but diagenetic alteration (especially condensation of cyclic moieties) was much smaller than for amber, implying that the manufacturers used resin (or copal), not amber. These results were confirmed by FTIR, which allowed identification of non-fossil Hymenaea resin as the main constituent of one of the resin figurines. Several golden object infillings contained wax derivatives, probably beeswax, accompanied by various types of plant resin, which may well indicate the use of meliponines’ cerumen for manufacturing (lost-wax casting). The findings highlight the potential of complementary molecular techniques to resolve questions on materials and manufacturing of archaeological artefacts, and the need for crosscomparison of molecular and ethnographic information in the study of archaeobotanical remains and the processes involved in their management.

  • Graph classes generated by Mycielskians
    • Mieczysław Borowiecki
    • Piotr Borowiecki
    • Ewa Drgas-Burchardt
    • Elżbieta Sidorowicz
    2020 Pełny tekst Discussiones Mathematicae Graph Theory

    In this paper we use the classical notion of weak Mycielskian M'(G) of a graph G and the following sequence: M'_{0}(G) =G, M'_{1}(G)=M'(G), and M'_{n}(G)=M'(M'_{n−1}(G)), to show that if G is a complete graph oforder p, then the above sequence is a generator of the class of p-colorable graphs. Similarly, using Mycielskian M(G) we show that analogously defined sequence is a generator of the class consisting of graphs for which the chromatic number of the subgraph induced by all vertices that belong to at least one triangle is at most p. We also address the problem of characterizing the latter class in terms of forbidden graphs.

  • Green Chromatography: State-of-the-art, Opportunities and Future Perspectives
    • Justyna Płotka-Wasylka
    • Magdalena Fabjanowicz
    • Kaja Kalinowska
    • Jacek Namieśnik
    2020

    It is well known that chromatographic procedures could have a significant impact on the environment if laboratory practice is not in line with the principles of green analytical chemistry (GAC). However, chromatographic techniques have the potential to be greener in all steps of the analysis. The approaches used to make chromatographic separations greener differ depending on the type of chromatographic method. This chapter considers the ways in which chromatography can become greener. Liquid and gas chromatography are compared from the GAC point of view. In addition, the importance of miniaturization in sample preparation and chromatographic separations is pointed out. On-line process analysers and portable chromatographs are also discussed.

  • Green thermoplastic poly(ether-urethane)s – synthesis, chemical structure and selected properties investigation
    • Paulina Kasprzyk
    • Kamila Błażek
    • Paulina Parcheta
    • Janusz Datta
    2020 Pełny tekst Polimery

    This work aimed to characterize the effect of the monomers chemical structure on the selected properties of the green thermoplastic poly(ether-urethane)s. During synthesis two types of polyether biopolyols, 4,4′-diphenylmethane diisocyanate and bio-based 1,3-propanediol were employed. Materials were synthesized with the use of two step method and two different prepolymers, which were mixed together in equimolar quantities. Obtained materials were characterized by spectroscopic method, size exclusion chromatography, thermal, static mechanical and melt flow index tests. It was confirmed that the prepolymers mixture has an effect on the thermal stability and selected properties of synthesized green thermoplastic poly(ether-urethane)s.

  • Grimm Grass 1 (Słówka Grimmów)
    • Krzysztof Wróblewski
    2020

    Krzysztof Wróblewski | Eksperyment: Ekslibris - ekslibris do powieści „Słówka Grimmów” Güntera Grassa LINK DO PREZENTACJI EKSLIBRISU → https://youtu.be/823ryLQzxas W swoim ekslibrisie Krzysztof Wróblewski sięgnął po technikę graficzną linorytu. Dzięki niej artysta osiągnął efekt powtarzalnego, dynamicznego znaku-plamy, który stanowi kwintesencję wypowiedzi z pogranicza sztuk wizualnych i literatury. Zainspirowany poezją konkretną, gdzie rytm, autonomia słowa, gry językowe i eksperymenty formalne odgrywają kluczową rolę, Wróblewski bardzo silnie nawiązał także do swojego własnego rozpoznawalnego sposobu wypowiedzi twórczej. Polega on na przenikaniu się form, równorzędności abstrakcji i rzeczywistości, wizualnych zagadkach, zacieraniu znaczeń i kreowaniu nowych, odkrywaniu i zakrywaniu wizerunków i treści. Jest w nim sporo formalnej precyzji a jednocześnie przypadkowości, gier logicznych i semantycznych, fascynacji geometrią, rozważań z pogranicza estetyki i tekstu. Stawiane przez Wróblewskiego znaki działają jako całość, ale także stają się indywidualnymi bytami. Wizualizują analogie i różnice pomiędzy poszczególnymi słowami zaczerpniętymi z języka polskiego i niemieckiego, a także stanowią analizę rytmu i struktury nazwisk: Grass i Grimm. Artysta bowiem zmierzył się z jedną z najtrudniejszych powieści Grassa, jaką są „Słówka Grimmów”. Cała książka stanowi eksperyment werbalny, nieustanny pojedynek treści i formy. Każdy z rozdziałów inspirowany jest kolejną literą alfabetu, rozpoczynającą słowa, z których skomponowana jest jego zawartość. Stąd też powieść ta uznawana jest przez wielu tłumaczy za nieprzekładalną na inne języki. Ewidentnym wyjątkiem jest tu język sztuki, sprzyjający eksperymentowaniu i skomplikowanym uwikłaniom zachodzącym pomiędzy dyscyplinami twórczymi.

  • Grimm Grass 2 (Słówka Grimmów)
    • Krzysztof Wróblewski
    2020

    Krzysztof Wróblewski | Eksperyment: Ekslibris - ekslibris do powieści „Słówka Grimmów” Güntera Grassa LINK DO PREZENTACJI EKSLIBRISU → https://youtu.be/823ryLQzxas W swoim ekslibrisie Krzysztof Wróblewski sięgnął po technikę graficzną linorytu. Dzięki niej artysta osiągnął efekt powtarzalnego, dynamicznego znaku-plamy, który stanowi kwintesencję wypowiedzi z pogranicza sztuk wizualnych i literatury. Zainspirowany poezją konkretną, gdzie rytm, autonomia słowa, gry językowe i eksperymenty formalne odgrywają kluczową rolę, Wróblewski bardzo silnie nawiązał także do swojego własnego rozpoznawalnego sposobu wypowiedzi twórczej. Polega on na przenikaniu się form, równorzędności abstrakcji i rzeczywistości, wizualnych zagadkach, zacieraniu znaczeń i kreowaniu nowych, odkrywaniu i zakrywaniu wizerunków i treści. Jest w nim sporo formalnej precyzji a jednocześnie przypadkowości, gier logicznych i semantycznych, fascynacji geometrią, rozważań z pogranicza estetyki i tekstu. Stawiane przez Wróblewskiego znaki działają jako całość, ale także stają się indywidualnymi bytami. Wizualizują analogie i różnice pomiędzy poszczególnymi słowami zaczerpniętymi z języka polskiego i niemieckiego, a także stanowią analizę rytmu i struktury nazwisk: Grass i Grimm. Artysta bowiem zmierzył się z jedną z najtrudniejszych powieści Grassa, jaką są „Słówka Grimmów”. Cała książka stanowi eksperyment werbalny, nieustanny pojedynek treści i formy. Każdy z rozdziałów inspirowany jest kolejną literą alfabetu, rozpoczynającą słowa, z których skomponowana jest jego zawartość. Stąd też powieść ta uznawana jest przez wielu tłumaczy za nieprzekładalną na inne języki. Ewidentnym wyjątkiem jest tu język sztuki, sprzyjający eksperymentowaniu i skomplikowanym uwikłaniom zachodzącym pomiędzy dyscyplinami twórczymi.

  • Ground Tire Rubber Modified by Ethylene-Vinyl Acetate Copolymer: Processing, Physico-Mechanical Properties, Volatile Organic Compounds Emission and Recycling Possibility
    • Łukasz Zedler
    • Paulina Burger
    • Shifeng Wang
    • Krzysztof Formela
    2020 Pełny tekst Materials

    Ground tire rubber (GTR) was reclaimed and modified with 10 phr of ethylene-vinyl acetate copolymer via low-temperature extrusion process. Processing, physico-mechanical properties, volatile organic compounds emission, and recycling possibility were investigated. In order to better understand the impact of used modifiers, their efficiency was compared with transpolyoctenamer, which is an additive that is commercially dedicated to waste rubber recycling. The results showed that a relatively small amount of ethylene-vinyl acetate copolymer improves the mechanical properties of modified reclaimed GTR and also allows further recycling by multiple processing without the deterioration of performance after three cycles.

  • Guest Editorial
    • Jakub Szczepański
    2020 Pełny tekst World Transactions on Engineering and Technology Education

    Architectural Education

  • Heavy Metals in a High Arctic Fiord and Their Introduction with the Wastewater: A Case Study of Adventfjorden-Longyearbyen System, Svalbard
    • Agnieszka Kalinowska
    • Małgorzata Szopińska
    • Stanisław Chmiel
    • Magdalena Kończak
    • Żaneta Polkowska
    • Wojciech Artichowicz
    • Katarzyna Jankowska
    • Aga Nowak
    • Aneta Łuczkiewicz
    2020 Pełny tekst Water

    Longyearbyen is the largest settlement on Svalbard archipelago, with 2400 permanent residents and approximately 150,000 tourists visiting every year. The city annually releases approximately 285,000 m3 of untreated wastewater to the nearby Adventfjorden. To date, the environmental impact of this continuous input has been studied mainly regarding the sediments and benthic fauna in the fiord. Here, we present results from a study of raw wastewater entering Adventfjorden as well as heavy metals concentrations in the water column within the fjord itself. Two surveys were carried out in summer and autumn season 2018, to establish physical and chemical properties of water at various locations. Trace elements (V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Hg, As, Cd, Pb, U), total suspended solids (TSS) and total organic carbon (TOC) were measured. Our results show that Longyearbyen’s raw wastewater introduces low concentrations of heavy metals to the fiord, but due to the growing number of inhabitants and tourists, it should be monitored to avoid degradation of Adventfjorden ecosystem

  • Henryk Hadrian i jego praca w Instytucie Elektrotechniki i na Politechnice Gdańskiej
    • Witold Parteka
    2020 Pełny tekst Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej

    W artykule przedstawiono sylwetkę Henryka Hadriana, absolwenta Wydziału Budowy Maszyn i Elektrotechniki politechniki w Gdańsku z 1935 roku. W latach 1945-1950 pracował w Zjednoczeniu Stoczni Polskich w Gdańsku, a w latach 1951- 1975 w gdańskim oddziale Instytutu Elektrotechniki, gdzie zorganizował i kierował działem elektrotechniki okrętowej, a także w centrali w Warszawie. Od przejścia na emeryturę w 1975, pełnił do 1990 roku funkcję rzecznika patentowego i konsultanta z zakładami pracy do spraw patentów i wdrożeń na Wydziale Elektrycznym Politechniki Gdańskiej .

  • Hierarchical MnO2 nanoflowers blooming on 3D nickel foam: A novel micro-macro catalyst for peroxymonosulfate activation
    • Ruixia Yuan
    • Zhongqiu Jiang
    • Zhaohui Wang
    • Simeng Gao
    • Zhanjian Liu
    • Meiling Li
    • Grzegorz Boczkaj
    2020 JOURNAL OF COLLOID AND INTERFACE SCIENCE

    In this work, birnessite-type δ-MnO2 nanoflowers were uniformly deposited on 3D nickel foam (NF) by one-step hydrothermal route for high-efficient activation of peroxymonosulfate (PMS) towards degradation of acid orange 7 (AO7). High specific surface area, large pore volume and 3D hierarchical structure promotes the mass and electron transfer for great catalytic activity. Low reaction energy barrier (Ea=27.5 kJ/mol) and outstanding reusability with extremely low manganese leaching during recycling (< 0.06 mg/L) was achieved due to the 3D hierarchical structure which could effectively avoid the agglomeration of nano-sized MnO2. SO4•- was confirmed to be the predominant reactive species for AO7 decomposition by electron spin resonance and quenching tests. The synergistic catalytic mechanism of MnO2/NF and the role of inner-sphere complexation between the active sites of MnO2 and peroxymonosulfate were thoroughly investigated. Compared with traditional nano/micro-sized catalysts, 3D macroscopic MnO2/NF with facile recovery and high stability potentially facilitates fascinating applications as green heterogeneous catalysis approach.

  • High catalytic performance of laccase wired to naphthylated multiwall carbon nanotubes
    • A. Ben Tahar
    • Kamila Sadowska
    • Jan Biernat
    • Ewa Paluszkiewicz
    • P. Cinquin
    • D. Martin
    • A. Zebda
    2020 Pełny tekst BIOSENSORS & BIOELECTRONICS

    The direct electrical connection of laccase on the electrode surface is a key feature in the design of efficient and stable biocathodes. However, laccases can perform a direct electron transfer only when they are in the preferable orientation toward the electrode. Here we report the investigation of the orientation of Laccase from Amano on multi-walled carbon nanotube surface modified with naphthalene group. Naphthylated multi wall carbon nanotubes were synthesized and the kinetics of Amano laccase adsorption and its direct electro catalytic activity toward oxygen reduction were investigated by QCM and electrochemical technics. Compared to pristine multi-walled carbon nanotube, laccase shows a high affinity to be adsorbed on naphthylated carbon nanotube. Moreover, laccase adsorption on naphthylated multi-walled carbon nanotubes surface is a very fast process and its electrical wiring to naphthylated multi-walled carbon nanotubes is accompanied by a reorientation and arrangement of adsorbed laccase. The naphthylated carbon nanotubes composite biocathode exhibits a high-performance biocathodes for oxygen reduction by direct electron transfer with maximum current densities of 3 mAcm-2.

  • Higher Responsiveness to Rosuvastatin in Polygenic versus Monogenic Hypercholesterolemia: A Propensity Score Analysis
    • Agnieszka Mickiewicz
    • Marta Futema
    • Agnieszka Ćwiklinska
    • Agnieszka Kuchta
    • Maciej Jankowski
    • Mariusz Kaszubowski
    • Magdalena Chmara
    • Bartosz Wasąg
    • Marcin Fijałkowski
    • Miłosz Jaguszewski
    • Steve E. Humphries
    • Marcin Gruchała
    2020 Pełny tekst Life

    Background: The monogenic defect in familial hypercholesterolemia (FH) is detected in ∼40% of cases. The majority of mutation-negative patients have a polygenic cause of high LDL-cholesterol (LDL-C). We sought to investigate whether the underlying monogenic or polygenic defect is associated with the response to rosuvastatin. Methods: FH Individuals were tested for mutations in LDLR and APOB genes. A previously established LDL-C-specific polygenic risk score (PRS) was used to examine the possibility of polygenic hypercholesterolemia in mutation-negative patients. All of the patients received rosuvastatin and they were followed for 8 ± 2 months. A propensity score analysis was performed to evaluate the variables associated with the response to treatment. Results: Monogenic subjects had higher mean (±SD) baseline LDL-C when compared to polygenic (7.6 ± 1.5 mmol/L vs. 6.2 ± 1.2 mmol/L; p < 0.001). Adjusted model showed a lower percentage of change in LDL-C after rosuvastatin treatment in monogenic patients vs. polygenic subjects (45.9% vs. 55.4%, p < 0.001). The probability of achieving LDL-C targets in monogenic FH was lower than in polygenic subjects (0.075 vs. 0.245, p = 0.004). Polygenic patients were more likely to achieve LDL-C goals, as compared to those monogenic (OR 3.28; 95% CI: 1.23-8.72). Conclusion: Our findings indicate an essentially higher responsiveness to rosuvastatin in FH patients with a polygenic cause, as compared to those carrying monogenic mutations.

  • Highly Conserved Homotrimer Cavity Formed by the SARS-CoV-2 Spike Glycoprotein: A Novel Binding Site
    • Umesh Kalathiya
    • Monikaben Padariya
    • Marcos Mayordomo
    • Małgorzata Lisowska
    • Judith Nicholson
    • Ashita Singh
    • Maciej Bagiński
    • Robin Fahraeus
    • Neil Carragher
    • Kathryn Ball
    • Juergen Haas
    • Alison Daniels
    • Ted R. Hupp
    • Javier Antonio Alfaro
    2020 Pełny tekst Journal of Clinical Medicine

    An important stage in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) life cycle is the binding of the spike (S) protein to the angiotensin converting enzyme-2 (ACE2) host cell receptor. Therefore, to explore conserved features in spike protein dynamics and to identify potentially novel regions for drugging, we measured spike protein variability derived from 791 viral genomes and studied its properties by molecular dynamics (MD) simulation. The findings indicated that S2 subunit (heptad-repeat 1 (HR1), central helix (CH), and connector domain (CD) domains) showed low variability, low fluctuations in MD, and displayed a trimer cavity. By contrast, the receptor binding domain (RBD) domain, which is typically targeted in drug discovery programs, exhibits more sequence variability and flexibility. Interpretations from MD simulations suggest that the monomer form of spike protein is in constant motion showing transitions between an “up” and “down” state. In addition, the trimer cavity may function as a “bouncing spring” that may facilitate the homotrimer spike protein interactions with the ACE2 receptor. The feasibility of the trimer cavity as a potential drug target was examined by structure based virtual screening. Several hits were identified that have already been validated or suggested to inhibit the SARS-CoV-2 virus in published cell models. In particular, the data suggest an action mechanism for molecules including Chitosan and macrolides such as the mTOR (mammalian target of Rapamycin) pathway inhibitor Rapamycin. These findings identify a novel small molecule binding-site formed by the spike protein oligomer, that might assist in future drug discovery programs aimed at targeting the coronavirus (CoV) family of viruses.

  • High-Temperature Oxidation of Heavy Boron-Doped Diamond Electrodes: Microstructural and Electrochemical Performance Modification
    • Jacek Ryl
    • Mateusz Cieślik
    • Artur Zieliński
    • Mateusz Ficek
    • Bartłomiej Dec
    • Kazimierz Darowicki
    • Robert Bogdanowicz
    2020 Pełny tekst Materials

    In this work, we reveal in detail the effects of high-temperature treatment in air at 600 °C on the microstructure as well as the physico-chemical and electrochemical properties of boron-doped diamond (BDD) electrodes. The thermal treatment of freshly grown BDD electrodes was applied, resulting in permanent structural modifications of surface depending on the exposure time. High temperature affects material corrosion, inducing crystal defects. The oxidized BDD surfaces were studied by means of cyclic voltammetry (CV) and scanning electrochemical microscopy (SECM), revealing a significant decrease in the electrode activity and local heterogeneity of areas owing to various standard rate constants. This effect was correlated with a resultant increase of surface resistance heterogeneity by scanning spreading resistance microscopy (SSRM). The X-ray photoelectron spectroscopy (XPS) confirmed the rate and heterogeneity of the oxidation process, revealing hydroxyl species to be dominant on the electrode surface. Morphological tests using scanning electron microscopy (SEM) and atomic force microscopy (AFM) revealed that prolonged durations of high-temperature treatment lead not only to surface oxidation but also to irreversible structural defects in the form of etch pits. Our results show that even subsequent electrode rehydrogenation in plasma is not sufficient to reverse this surface oxidation in terms of electrochemical and physico-chemical properties, and the nature of high-temperature corrosion of BDD electrodes should be considered irreversible.

  • High-Temperature Structural and Electrical Properties of BaLnCo2O6 Positrodes
    • Iga Szpunar
    • Ragnar Strandbakke
    • Magnus H. Sorby
    • Sebastian Wachowski
    • Maria Balaguer
    • Mateusz Tarach
    • José M Serra
    • Agnieszka Witkowska
    • Ewa Dzik
    • Truls Norby
    • Maria Gazda
    • Aleksandra Mielewczyk-Gryń
    2020 Pełny tekst Materials

    The application of double perovskite cobaltites BaLnCo2O6−δ (Ln = lanthanide element) in electrochemical devices for energy conversion requires control of their properties at operating conditions. This work presents a study of a series of BaLnCo2O6−δ (Ln = La, Pr, Nd) with a focus on the evolution of structural and electrical properties with temperature. Symmetry, oxygen non-stoichiometry, and cobalt valence state have been examined by means of Synchrotron Radiation Powder X-ray Diffraction (SR-PXD), thermogravimetry (TG), and X-ray Absorption Spectroscopy (XAS). The results indicate that all three compositions maintain mainly orthorhombic structure from RT to 1000 °C. Chemical expansion from Co reduction and formation of oxygen vacancies is observed and characterized above 350 °C. Following XAS experiments, the high spin of Co was ascertained in the whole range of temperatures for BLC, BPC, and BNC.