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4-(Cyclic-amidino)phenols. Preparation and Use in a Diamidine Synthesis
PublicationThe Pinner synthesis was applied to the prepn. of phenols 4-substituted with cyclic amidines in high yields from readily available 4-HOC6H4C(OMe):NH.HCl and aliph. diamines. An alternative attempt was made to convert 4-HOC6H4CSNH2 to 4-(1,4,5,6-tetrahydro-5-hydroxy-2-pyrimidinyl)phenol. A procedure for the prepn. of 3,6-bis(4-hydroxyphenyl)-1,2,4,5-tetrazine is reported. The syntheses of 2,4-bis[4-(4,5-dihydro-1H-imidazol-2-yl)phenoxy]pyrimidine...
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Methods for the synthesis of xanthine-derived polycyclic fused systems
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Mesenchymal stem cells transfer mitochondria to allogeneic Tregs in an HLA-dependent manner improving their immunosuppressive activity
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Distinguishing between polymorphic forms of linezolid by solid-phase electronic and vibrational circular dichroism
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Molecular insights into receptor binding energetics and neutralization of SARS-CoV-2 variants
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A new method for preparation of rutile phase titania photoactive under visible light
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TMSCL as a rate accelerating additive in acylations of amines with 5-(α- amino-α'-hydroxy)methylene meldrum's acids
PublicationAspects are presented of the acylation of amines, alcohols and thiols with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids. We placed special emphasis on the acylation reaction of secondary amines with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids, which, due to their basicity, caused problems concerning salt formation with a Meldrum acid derivative. We found that secondary amines, which react at the slowest rate and with a...
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One-step formation of n-alkenyl-malonamides and n-alkenyl-thiomalonamides from carbamoyl meldrum's acids.
PublicationA one-pot synthesis for the preparation of N-alkenyl-malonamides and N-alkenyl-thiomalonamides was developed. 5-[Hydroxy/mercapto(aryl/alkylamino)methylene]-2,2-dimethyl-1,3-dioxane-4,6-dione act as a source of ketenes that react with the tautomeric form of alkyl-(2-phenyl-propylidene)-amines. A possible [2+2] or [4+2] cycloaddition product of ketene to imines was not observed.
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Novel calix[4]resorcinarenes with side azobenzo-15-crown-5 residues
PublicationZsyntezowano nowe kaliks[4]rezorcareny z dwoma lub czteroma resztami azobenzo-15-korony-5 w dowolnym pierścieniu. Związki te otrzymano w reakcji kondensacji rezorcynolu z odpowiednimi aldehydami (acetalami).
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Facile synthetic route to selectively protected spermidine homologues
PublicationW wyniku opracowanej procedury otrzymano kilka selektywnie chronionych homologów spermidyny. Reakcja cyjanoetylowania monochronionych diamin pozwoliła na otrzymanie nitryli, które przekształcano w amidy pierwszorzędowe. Degradacja Hofmanna amidów doprowadziła do otrzymania finalnych związków.
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Visible light-induced photocatalytic reaction of gold-modified titanium(IV) oxide particles: action spectrum analysis
PublicationAnalizy spektrum działania wykazały, ze wzbudzenie powierzchniowego plazmonu złota inicjuje utlenianie 2-propanolu w świetle widzialnym w napowietrzonej zawiesinie tlenku(IV) tytanu zmodyfikowanego zlotem. Badania przeprowadzone z użyciem światła polichromatycznego wykazały, ze szybkość reakcji foto-utleniania zależy od właściwości tlenku(IV) tytanu, takich jak rozmiar ziaren, pola powierzchni właściwej, formy krystalicznej (anataz...
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Powerful connection of laccase and carbon nanotubes: Material for mediator-free electron transport on the enzymatic cathode of the biobattery
PublicationOpisany został sposób wytwarzania koniugatów lakaza - jednościenne nanorurki węglowe i ich zastosowanie jako materiałów modyfikujacych katodę w hybrydowym bioogniwie paliwowym z cynkową anodą. Nanorurki węglowe z przyłączonymi grupami aminoetylowymi stanowiły materiał wyjściowy do chemicznego związania lakazy na ich powierzchni. Otrzymany materiał wykazywał wysoką aktywność bioelektrokatalityczną i jest obiecujacym materiałem do...
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Fully enzymatic mediatorless fuel cell with efficient naphthylated carbon nanotube-laccase composite cathodes
PublicationAn efficient, mediator-free enzymatic glucose/O2 biofuel cell with an oxygen intensive anode based on glucose dehydrogenase is presented. In the device,the power of the biofuel cell and electrode potentials of each of the enzymatic electrodes were monitored in parallel under the biofuel cell working conditions. The carbon nanotube composite biocathode demonstrates an almost constant electrode potential vs. saturated calomel electrode...
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Heterogeneous distribution of surface electrochemical activity in polycrystalline highly boron-doped diamond electrodes under deep anodic polarization
PublicationThe surface homogeneity of boron-doped diamond electrodes is variable and depends on anodic polarization conditions. The differentiation factor is the gradual and localized change in surface termination. A series of measurements under different polarization conditions was performed in order to investigate the scale of this effect. Nanoscale impedance microscopy (NIM) revealed large variation of surface resistance in individual...
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Infrared response of multiwalled boron nitride nanotubes
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Fe-promoted CuO/CeO2 catalyst
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Surface properties of wustite based iron-cobalt catalysts for ammonia synthesis reaction
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Electrochemical formation of the adduct between antitumor agent C_1311 and DNA nucleoside dG. 75.
PublicationPrzyjmuje się, że metaboliczna aktywacja przeciwnowotworowej pochodnej C_1311 jest procesem koniecznym dla jej aktywności przeciwnowotworowej. Wykazano wcześniej, że taka aktywacja prowadzi do kowalencyjnego wiązania się leku z DNA w komórce nowotworowej. Aby zbadać molekularny mechanizm powyższej reakcji metabolicznej przeprowadzono badania elektrochemicznego utleniania pochodnej C_1311. Wykazano w pracy, że dwa produkty elektrochemicznego...
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Cubane Like Structure of a Silanethiol Primary Amine Assembly a Novel, Unusual Hydrogen Bond Pattern.
PublicationMetodą rentgenowskiej analizy strukturalnej wyznaczono struktury krystaliczne i cząsteczkowe trzech soli amoniowych: (t-BuO)3SiS(-)H3N(+)Bu-t, (i-PrO)3SiS(-)H3N(+)Bu-t i (t-BuO)3SiS(-)H3N(+)(CH2)2CH(CH3)2. Wszystkie trzy związki w ciele stałym tworzą tetramery w których atomy S i N wyznaczają w przybliżeniu naroża sześcianu. Trwałość tych agregatów, oprócz sił elektrostatycznego przyciągania, zapewnia sieć wiązań wodorowych N-H
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Polynomial analysis as a new way of describing dynamic impedance spectra – Differential and relative impedance spectra
PublicationModel measurements of an equivalent electrical system were carried out using the technique of Dynamic Electrochemical Impedance Spectroscopy. The measurement took the form of potentiodynamic changes imposed on the tested system. Using the possibility of continuous impedance measurements, an attempt was made to develop an original and innovative method of analyzing impedance spectrograms, which is termed polynomial analysis. As...
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Atom-economic thiophosphoroselenenylations of C–H acid esters and amides
PublicationThree improved thiophosphoroselenenylation procedures of CHacids, including derivatives of malonic and acetyl-, phosphono-, 4-nitrophenyl- and 3-pyridylacetic acids, have been described and compared to previously reported thiophosphoroselenylation of diethyl malonate using bis(disopropoxyphosphinothioyl)diselenide alone or with the aid of methyl iodide. The use of iodine makes it possible to utilize both equivalents of the selenenylating...
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The comparative study of different methods of spectral analysis of electrochemical oscillations
PublicationOscylacje elektrochemiczne często połączone są z roztwarzaniem metali. One często wykazują niestacjonarny charakter. W związku z czym wydaje się konieczne wykonanie analizy w równoczesnej dziedzinie czasu i częstotliwości. Zaprezentowano porównanie trzech nowych metod: STFT, transformacji falkowej i rozkładu Wigner-Ville´a. Zalety tych metod zostały wypunktowane oraz wykazane zostały różnice pomiędzy analizą Fourierowską i technikami...
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Pitting corrosion in steel and electrochemical noise intensity
PublicationPrzedstawiono analizę szumu elektrochemicznego, rejestrowanego w obecności korozji wżerowej. Stwierdzono korelację pomiędzy intensywnością szumu a ubytkiem mas elektrod stalowych. Rejestry szumowe rozłożone zostały na składowe częstotliwościowe za pomocą przekształcenia falkowego. Dla pewnych składowych stwierdzono silniejszą korelację z ubytkiem mas korodujących elektrod. Pasmo częstotliwościowe powyższych składowych odpowiada...
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Bi-based halide perovskites: Stability and opportunities in the photocatalytic approach for hydrogen evolution
PublicationIn this study, we successfully prepared Bi-based single perovskites of the A3Bi2I9 type (A = Cs, Rb, MA, FA), and, for the first time, attempted to experimentally obtain double perovskites Cs2B’BiI6 type (B′ = Ag, Au, In, Cu). Despite the premises available in theoretical studies, our research has proven the impossibility of the existence of double perovskites of this type. Nevertheless, both types of obtained materials were subjected...
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Piezoresistive properties of cement composites with expanded graphite
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Flame retardant effect and mechanism of nanosized NiO as synergist in PLA/APP/CSi-MCA composites
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New thiourea organocatalysts and their application for the synthesis of 5-(1H-indol-3-yl)methyl-2,2-dimethyl-1,3-dioxane-4,6-diones a source of chiral 3-indoylmethyl ketenes
PublicationThe stereoselective properties of modified thiourea organocatalysts were tested in the Friedel–Crafts alkylation of indole with 5-arylidene-2,2-dimethyl-1,3-dioxane-4,6-diones, which produces chiral 5-((1H-indol-3-yl)(aryl)methyl)-2,2-dimethyl-1,3-dioxane-4,6-diones. Based on a tentative reaction mechanism for ((S)-N-benzyl-2-(3-(3,5-bis (trifluoromethyl)phenyl)thioureido)-N,3,3-trimethylbutanamide organocatalysts, modifications...
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Preparation of bicyclic β-lactam and bicyclic 1,3- oxazinone scaffolds using combined cycloaddition and metathesis processes
PublicationA simple, efficient two-step method for the preparation of heterobicyclic compounds was developed. Starting from 5-acyl or 5-carbamoyl-2,2- dimethyl-1,3-dioxa-4,5-dione bicyclic scaffolds of 1-azabicyclo[5.2.0]non- 3-en-9-one, 6,9,10,10a-tetrahydro-4H-[1,3]oxazino[3,2-a]azepin-4-one, and 6,9,10,10a-tetrahydro-2H-[1,3]oxazino[3,2-a]azepine-2,4(3H)-dione were prepared using cycloaddition of thermally generated ketenes to aldimines...
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Steering is an essential feature of non-locality in quantum theory
PublicationA physical theory is called non-local when observers can produce instantaneous effects over distant systems. Non-local theories rely on two fundamental effects: local uncertainty relations and steering of physical states at a distance. In quantum mechanics, the former one dominates the other in a well-known class of non-local games known as XOR games. In particular, optimal quantum strategies for XOR games are completely determined...
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Closed-loop stimulation of temporal cortex rescues functional networks and improves memory
PublicationMemory failures are frustrating and often the result of ineffective encoding. One approach to improving memory outcomes is through direct modulation of brain activity with electrical stimulation. Previous efforts, however, have reported inconsistent effects when using open-loop stimulation and often target the hippocampus and medial temporal lobes. Here we use a closed-loop system to monitor and decode neural activity from direct...
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Widespread theta synchrony and high-frequency desynchronization underlies enhanced cognition
PublicationThe idea that synchronous neural activity underlies cognition has driven an extensive body of research in human and animal neuroscience. Yet, insufficient data on intracranial electrical connectivity has precluded a direct test of this hypothesis in a whole-brain setting. Through the lens of memory encoding and retrieval processes, we construct whole-brain connectivity maps of fast gamma (30-100 Hz) and slow theta (3-8 Hz) spectral...
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Diphosphination of CO2 and CS2 mediated by frustrated Lewis pairs - catalytic route to phosphanyl derivatives of formic and dithioformic acid
PublicationThe first example of CO2 diphosphination is described. Reactions of unsymmetrical diphosphanes with CE2 (E = O, S) catalyzed by BPh3 insert a CE2 molecule into the P-P bond with formation of the products of the general formula R2P-E-C(=E)-PR2. The obtained CO2 adducts arise from synergistic interaction of diphosphane and borane with CO2 molecule.
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Phosphinoborinium cation: a synthon for cationic B-P bond systems
PublicationHerein, we report access to phosphinoborinium cations via heterolytic cleavage of the boron-bromide bond in bromophosphinoborane. The product of the reaction was isolated as a dimeric dication possessing a planar P2B2 core. Activation of C-H and C-P bonds in the dication led to formation of the borinium-phosphaborene adduct. Reactivity studies revealed that title cation exhibits ambiphilic properties and intramolecular frustrated...
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Polynomial description of dynamic impedance spectrogram—introduction to a new impedance analysis method
PublicationThis paper presents a polynomial description of spectrograms obtained using Dynamic Electrochemical Impedance Spectroscopy. A method to fit the polynomial degree correctly is discussed. A simple electrical system of a diode connected in parallel with a capacitor was used for testing. Dynamic impedance measurements during potentiodynamic polarization were conducted. This paper presents an alternative analysis method that allows...
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Oxidation step in the preparation of benzocamalexin: The crystallographic evidence
PublicationThe study of oxidation step in the preparation of benzocamalexin by the α-amidoalkylation–oxidation sequence revealed the formation of perchloro-1,2-phenylene dibenzoate as the product of transformation of tetrachloro- 1,2-benzoquinone applied as the oxidant. The structures of benzocamalexin and perchloro-1,2-phenylene dibenzoate were confirmed by X-ray diffraction analysis. The extraction step in the final isolation of benzocamalexin...
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Metal ion directed template synthesis using 2-acetyl-1,3-indandione and ethylenediamine: steric and electronic restrictions
PublicationA template synthesis using 2-acetyl-1,3-indandione and ethylenediamine results in formation of octahedral Ni complex, whose crystal structure has been resolved using single crystal X-ray diffraction. The structure indicates that only exocyclic enolic oxygen atom of the triketone takes part in the condensation with ethylenediamine.
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Electromagnetic Simulation with 3D FEM for Design Automation in 5G Era
PublicationElectromagnetic simulation and electronic design automation (EDA) play an important role in the design of 5G antennas and radio chips. The simulation challenges include electromagnetic effects and long simulation time and this paper focuses on simulation software based on finite-element method (FEM). The state-of-the-art EDA software using novel computational techniques based on FEM can not only accelerate numerical analysis, but...
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Differential analysis of dynamic immittance spectra
PublicationThis work presents a new approach to the analysis of immittance spectrograms of systems characterised by non-stationarity. The possibility of linking the evolution of the immittance response with changes in the parameters describing the system is achieved by introducing a spectrum in differential form. By using the above procedure, it becomes possible to separate elements with a dependence (or lack thereof) from an independent...
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Realistic noise-tolerant randomness amplification using finite number of devices
PublicationRandomness is a fundamental concept, with implications from security of modern data systems, to fundamental laws of nature and even the philosophy of science. Randomness is called certified if it describes events that cannot be pre-determined by an external adversary. It is known that weak certified randomness can be amplified to nearly ideal randomness using quantum-mechanical systems. However, so far, it was unclear whether randomness amplification...
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DNA methylation as a mediator of HLA-DRB1*15:01 and a protective variant in multiple sclerosis
PublicationThe human leukocyte antigen (HLA) haplotype DRB1*15:01 is the major risk factor for multiple sclerosis (MS). Here, we find that DRB1*15:01 is hypomethylated and predominantly expressed in monocytes among carriers of DRB1*15:01. A differentially methylated region (DMR) encompassing HLA-DRB1 exon 2 is particularly affected and displays methylation-sensitive regulatory properties in vitro. Causal inference and Mendelian randomization...
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Review on Wikification methods
PublicationThe paper reviews methods on automatic annotation of texts with Wikipedia entries. The process, called Wikification aims at building references between concepts identified in the text and Wikipedia articles. Wikification finds many applications, especially in text representation, where it enables one to capture the semantic similarity of the documents. Also, it can be considered as automatic tagging of the text. We describe typical...
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Fast collaborative graph exploration
PublicationWe study the following scenario of online graph exploration. A team of k agents is initially located at a distinguished vertex r of an undirected graph. At every time step, each agent can traverse an edge of the graph. All vertices have unique identifiers, and upon entering a vertex, an agent obtains the list of identifiers of all its neighbors. We ask how many time steps are required to complete exploration, i.e., to make sure...
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Fast Collaborative Graph Exploration
PublicationWe study the following scenario of online graph exploration. A team of k agents is initially located at a distinguished vertex r of an undirected graph. At every time step, each agent can traverse an edge of the graph. All vertices have unique identifiers, and upon entering a vertex, an agent obtains the list of identifiers of all its neighbors. We ask how many time steps are required to complete exploration, i.e., to make sure...
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Analysis of Impulse Responses Measured in Motion in a Towing Tank
PublicationThe growing interest in developing autonomous underwater vehicles (AUVs) and creating underwater sensor networks (USNs) has led to a need for communication tools in underwater environments. For obvious reasons, wireless means of communication are the most desirable. However, conducting research in real conditions is troublesome and costly. Moreover, as hydroacoustic propagation conditions change very significantly, even during...
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Analysis of Impulse Responses Measured in Motion in a Towing Tank
PublicationThe growing interest in developing autonomous underwater vehicles (AUVs) and creating underwater sensor networks (USNs) has led to a need for communication tools in underwater environments. For obvious reasons, wireless means of communication are the most desirable. However, conducting research in real conditions is troublesome and costly. Moreover, as hydroacoustic propagation conditions change very significantly, even during...
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A taxonomy of challenges to resilient message dissemination in VANETs
PublicationInter-vehicular communications is seen as a promising solution to a number of issues related with public road safety, road congestion management, and infotainment. However, Vehicular Ad-hoc NETworks (VANETs) characterized by high mobility of vehicles and facing a number of other issues related with high frequency wireless communications and network disconnections, encounter major challenges related with reliability of message delivery....
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APIS – Agent Platform for Integration of Services
PublicationThe paper presents an approach to creating the platform for development and evaluation of complex tasks execution algorithms. Proposed solution is based on an agent paradigm where independent peers can cooperate and negotiate in order to execute specified tasks which are defined only by the final output description. Tasks are realized by the means of services exposed by different peers. In case when there is no single service fulfilling...
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ICT and social development. Conceptual considerations.
PublicationThis chapter is intended to provide basic ideas and concepts related to technology, technological progress and society. It explains how and why technology and society are interrelated, forming a dynamic, complex and interdependent evolutionary system. It introduces the terms Digital (ICT) Revolution and information and communication technologies (ICTs), showing elementary features of new technologies. The chapter explains why ICTs...
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The Eastern Battery in Świnoujście, Poland - history and architecture of a Prussian coastal fort from the 19th century
PublicationThe article describes the history, architecture and development of the Eastern Battery (also known as the Gerhard Fort) – one of three remaining coastal forts in Świnoujście (former Swinemünde) located in northern Poland, by the Baltic Sea. The research is mostly based on historical cartographic material and architectural plans verified during field studies. This data served to create a digital model – one of the results of the...
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Reinforced Secure Gossiping Against DoS Attacks in Post-Disaster Scenarios
PublicationDuring and after a disaster, the perceived quality of communication networks often becomes remarkably degraded with an increased ratio of packet losses due to physical damages of the networking equipment, disturbance to the radio frequency signals, continuous reconfiguration of the routing tables, or sudden spikes of the network traffic, e.g., caused by the increased user activity in a post-disaster period. Several techniques have...