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Search results for: scholarly communication
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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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A general approach towards carbonization of plastic waste into a well-designed 3D porous carbon framework for super lithium-ion batteries
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Porous nanopeapod Pd catalyst with excellent stability and efficiency
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A graphene-based nanostructure with expanded ion transport channels for high rate Li-ion batteries
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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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Magnesium porphyrazine with peripheral methyl (3,5-dibromophenylmethyl)amino groups – synthesis and optical properties
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Synthesis of Novel Polycationic Quaternary Di- and Trispirocyclic Benzenes
PublicationTreatment of hexakis(bromomethyl)benzene with a cyclic amine {morpholine, 1-methylpiperazine, 1-(2-hydroxyethyl)piperazine, isonipecotamide, 4-hydroxypiperidine, 4-[3-(4-piperidyl)propyl]-1-piperidineethanol} gave a range of di- and trispirocyclic ammonium salts in satisfactory yields (22-62%). Presumably, the electrostatic and repulsion forces play an important role in their formation. The structure in soln. and the protonation...
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A Convenient Synthesis of Monocationic 1-[(Cyclic amidino)methyl]thymines
Publication1-[(Cyclic amidino)methyl]thymines have been conveniently synthesized from thymine in a three-step procedure via 1-cyanomethyl- and 1-[(thiocarbamoyl) methyl]thymines. The above synthetic intermediates were obtained in good yields by improved methods.
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Preparation of 1-[Ω-(1,4,5,6-Tetrahydropyrimidin-2-yl)alkyl]thymines
PublicationOne-stage prepn. of the hydrochloride salts of 1-[ω-(1,4,5,6-tetrahydropyrimidin-2-yl)alkyl]-thymines, e.g. I, from 1-(ω-cyanoalkyl)thymines and a 1:1-mixt. of 1,3-diaminopropane and ethanol satd. with hydrogen sulfide is described. 1-(2-Cyanoethyl)-thymine gave a facile reversal of the Michael reaction to thymine under the conditions used. The reaction of 1,3-bis(3-cyanobenzyl)thymine with the above reagent produced 1,3-bis[3-(1,4,5,6-tetrahydropyrimidin-2-yl)benzyl]thymine.
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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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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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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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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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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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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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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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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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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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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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Synthesis and reactivity of O-acyl selenophosphates
PublicationThe synthesis of several new O-acyl selenophosphates were investigated. The stability and reactivity of the products were studied and related to their structure.
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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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Analiza wpływu transmisji danych na jakość działania rozproszonych systemów sterowania
PublicationW artykule przedstawiono zagadnienia związane z transmisją danych w rozproszonych systemach sterowania. Opisano cechy charakterystyczne przemysłowych sieci i protokołów informatycznych. Utworzono model rozproszonego systemu sterowania poziomem cieczy w zbiorniku, w którym komunikacja oparta została na protokole Modbus RTU. Na podstawie zmian parametrów transmisji danych wykazano, że poprawna komunikacja pomiędzy elementami systemu...
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Low-Power WSN System for Honey Bee Monitoring
PublicationThe paper presents a universal low-power system for biosensory data acquisition in scope of bees monitoring. We describe the architecture of the system, energy-saving components as well as we discuss the selection of used sensors. The work focuses on energy optimization in a scope of wireless communication. A custom protocol was implemented, which is the basis for presented energy-efficient devices. Data exchange process during...
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THE INFLUENCE OF INTERPERSONAL MOTIVATION ON POLISH CONSUMERS’ ONLINE BRAND-RELATED ACTIVITY
PublicationThe development of social media has a substantial impact on the surge of social engagement of Internet users. It is particularly prominent in the domain of content creation and content sharing. Such communication may contain various references to different products brands and companies. Internet users may refer to them explicitly or brands may be present in the background only. Therefore, it is pivotal for managers and researchers...
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Quality Modeling in Grid and Volunteer-Computing Systems
PublicationA model of computational quality in large-scale computing systems was presented in the previous chapter of this book. This model describes three quality attributes: performance, reliability and energy efficiency. We assumed that all processes in the system are incessantly ready to perform calculations and that communication between the processes occurs immediately. These assumptions are not true for grid and volunteer computing...
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Wirtualne sieci 5G, NGN i następne. Radioinformatyczna metamorfoza sieci komórkowych
PublicationPrzedstawiono problematykę ewolucyjnej, a w zasadzie rewolucyjnej, metamorfozy komórkowych systemów radiokomunikacyjnych w kontekście architektury sieci 5G, zasad jej działania oraz nowych możliwości implementacyjnych usług sieci NGN. Artykuł dotyczy w szczególności istoty działania sieci 5G, łączącej w sobie cechy sieci radiokomunikacyjnych poprzednich generacji, zwłaszcza 4G, oraz nowe właściwości charakterystyczne dla 5G. Dotyczą...
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Trunked Radio Solutions for Special Application
PublicationIn the paper modern concepts of radio communication trunking-dispatch systems for special applications are presented. Basic standards of TETRA, DMR, and cdma2000 are mentioned. The aim of the paper is to present innovative trunking solutions based on the LTE system working both in FDD and TDD mode. The architecture of LTE trunked radio is shown as well as new services possible to implementation are described. The way of TETRA and...