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Year 2025
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Analysis of Instantaneous Ship Resistance-Increase in Waves with CFD URANS
PublicationTo comply with the requirements set out by the International Maritime Organization (IMO) for reducing greenhouse gas (GHG) emissions, recent efforts have focused on investigating the parameters that affect the increase in ship resistance, with the aim of developing effective reduction methods. This research examines both the time-varying instantaneous characteristics of a ship’s resistance in waves, referred to as resistance-increase,...
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Analysis of the correlation between instantaneous resistance-increase in waves and ship motion for reducing fuel consumption
PublicationReducing fuel consumption is crucial for greening water transport. Wind, waves and currents affect fuel usage, with wave-induced resistance being significant. Typically, added resistance is estimated as the time average of resistance increase in waves over calm water. However, this average lacks real-time utility for engine adjustments. This study analyses time-series correlations between wave-induced resistance-increase and ship...
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Investigation of the thrust generated by active isolated hydrofoils via wave-induced ship motion
PublicationWave Augmented Hydrofoil Technology (WAHT) aims to convert hydrofoil movement, induced by ship motion, into thrust force, and ship's resistance reduction in waves. Despite the growing interest in WAHT, a significant research gap remains in understanding the complex interactions between hydrofoil design parameters and wave-induced thrust generation. A hydrofoil attached to a ship serves dual roles; reducing the ship resistance in...
Year 2024
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Convenient and efficient N-methylation of secondary amines under solvent-free ball milling conditions
PublicationIn the present work, we report the development of a rapid, efcient, and solvent-free procedure for the N-methylation of secondary amines under mechanochemical conditions. After optimization of the milling parameters, a vibrational ball mill was used to synthesize 26 tertiary N-methylated amine derivatives in a short time of 20 min (30 Hz frequency) and high yields ranging from 78 to 95%. An exception was compounds having a hydroxyl...
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Development of potent and effective SARS-CoV-2 main protease inhibitors based on maleimide analogs for the potential treatment of COVID-19
PublicationIn the present work, we report a new series of potent SARS-CoV-2 Main Protease (Mpro) inhibitors based on maleimide derivatives. The inhibitory activities were tested in an enzymatic assay using recombinant Mpro (3CL Protease from coronavirus SARS-CoV-2). Within the set of new Mpro inhibitors, 6e demonstrated the highest activity in the enzymatic assay with an IC50 value of 8.52 ± 0.44 mM. The IC50 value for Nirmatrelvir (PF-07321332,...
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Investigating Fuel Injection Strategies to Enhance Ship Energy Efficiency in Wave Conditions
PublicationThe prediction of fuel consumption and resulting transportation costs is a crucial stage in ship design, particularly for conditions involving motion in waves. This study investigates the real-time fuel consumption of a container ship when sailing in waves. The overall ship performance is evaluated using a novel non-linear coupled hull-engine-propeller interaction model. A series of towing tank experiments for hull resistance in...
Year 2023
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Negative impact of constant RPM control strategy on ship NOx emission in waves
PublicationIn severe wave conditions, the ship propulsion system is loaded with high fluctuations due to external disturbances. The highly fluctuating loads enforce radical changes in the main engine torque, which in turn demands variation of the fuel rate injected into the cylinders if a constant rotational speed strategy is applied. Therefore, the temperature of gases varies to a large extent during the combustion process in the cylinders....
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On the Possibility of Increasing Ship Energy Efficiency Through Improved Propulsion Control System
PublicationThis paper summarizes the analyses conducted to assess the impact of the ship's propulsion control system on energy efficiency in calm, manoeuvre, and sea wave conditions, where the goal of the investigation is to develop new strategies for controlling the ship's motion while considering the interactions between the hull, engine, and propeller.
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TIME-DOMAIN NUMERICAL EVALUATION OF SHIP RESISTANCE AND MOTION IN REGULAR WAVES BY USING THE CFD URANS METHOD
PublicationTaking into account the International Maritime Organisation’s (IMO) strategy to radically reduce the GHG emitted by the shipping industry towards zero emission operation, today's assessment of ship behaviour in waves, its seakeeping characteristics and resistance and their interrelation with fuel consumption and emissions are one of the most attended research subject. There are three methods to conduct this analysis, which are...
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TIME-DOMAIN NUMERICAL EVALUATION OF SHIP RESISTANCE AND MOTION IN REGULAR WAVES BY USING THE CFD URANS METHOD
PublicationTaking into account the International Maritime Organization's (IMO) strategy to radically reduce the...
Year 2022
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Development of Sulfamoylated 4‑(1-Phenyl‑1H‑1,2,3-triazol-4-yl)phenol Derivatives as Potent Steroid Sulfatase Inhibitors for Efficient Treatment of Breast Cancer
PublicationWe present here the advances achieved in the development of new sulfamoylated 4-(1-phenyl-1H-1,2,3-triazol-4-yl)phenol derivatives as potent steroid sulfatase (STS) inhibitors for the treatment of breast cancer. Prompted by promising biological results and in silico analysis, the initial series of similar compounds were extended, appending a variety of m-substituents at the outer phenyl ring. The inhibition profiles of the newly...
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Digitalization of High Speed Craft Design and Operation Challenges and Opportunities
PublicationIn recent years, global demands for safe and sustainable ships led to dramatic changes in the maritime industry. Digitalization is expected to play an important part in the future. This is supported by analysis of the autonomous ships market which shows that digitalization of large ship types such as tankers and container ships is well on track. Although to date designs of autonomous High-Speed Craft (HSC) have been developed,...
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Impact of Propeller Emergence on Hull, Propeller, Engine, and Fuel Consumption Performance in Regular Head Waves
PublicationIn this study, the impact of propeller emergence on the performance of a ship (speed), propeller (thrust, torque, and RPM), a diesel engine (torque and RPM) and fuel consumption are analysed under severe sea conditions. The goal is to describe the variation in the system variables and fuel consumption rather than analysing the motion of the ship or the phenomenon of propeller ventilation in itself. A mathematical model of the...
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The effect of Sr and Mg substitutions on structure, mechanical properties and solubility of fluorapatite ceramics for biomedical applications
PublicationIonic substitutions play important role in the modifications of biological apatites. Recently, attention has been focused on the co-doping effects on the functional properties of apatite-based biomaterials. In this research work, the dense samples of fluorapatites, Ca10(PO4)6F2 and Ca8MgSr(PO4)6F2, were produced after sintering at 1250 °C for 6 h in air. Structural characterization carried out with XRD, IR, Raman and SEM, confirmed...
Year 2021
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Anticancer Properties of Amino Acid and Peptide Derivatives of Mycophenolic Acid
PublicationBackground: Although Mycophenolic Acid (MPA) is applied as prodrugs in clinic as an immunosuppressant, it also possesses anticancer activity. MPA acts as Inosine-5’-Monophosphate Dehydrogenase (IMPDH) inhibitor, where the carboxylic group at the end of the side chain interacts with Ser 276 of the enzyme via hydrogen bonds. Therefore, MPA derivatives with other polar groups indicated high inhibition too. On the other hand, potent...
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New potent steroid sulphatase inhibitors based on 6-(1-phenyl-1H-1,2,3-triazol-4-yl)naphthalen-2-yl sulphamate derivatives
PublicationIn the present work, we report a new class of potent steroid sulphatase (STS) inhibitors based on 6-(1-phenyl-1H-1,2,3-triazol-4-yl)naphthalen-2-yl sulphamate derivatives. Within the set of new STS inhibitors, 6-(1-(1,2,3-trifluorophenyl)-1H-1,2,3-triazol-4-yl)naphthalen-2-yl sulphamate 3L demonstrated the highest activity in the enzymatic assay inhibiting the STS activity to 7.98% at 0.5 µM concentration. Furthermore, to verify...
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Novel 1,2,3-Triazole Derivatives as Mimics of Steroidal System—Synthesis, Crystal Structures Determination, Hirshfeld Surfaces Analysis and Molecular Docking
PublicationHerein, we present the synthesis and crystal structures determination of five 4-(1-phenyl-1H-1,2,3-triazol-4-yl)phenol derivatives containing halogen atoms, 6a–e, which may be used as an excellent mimic of steroids in the drug development process. Good quality crystals obtained for all of the synthesized compounds allowed the analysis of their molecular structures. Subsequently, the determined crystal structures were used to calculate...
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Performance and Emission Modelling and Simulation of Marine Diesel Engines using Publicly Available Engine Data
PublicationTo analyse the behaviour of marine diesel engines in unsteady states for different purposes, for example to determine the fuel consumption or emissions level, to adjust the control strategy, to manage the maintenance, etc., a goal-based mathematical model that can be easily implemented for simulation is necessary. Such a model usually requires a wide range of operating data, measured on a test stand. This is a time-consuming process...
Year 2020
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Analysis of hull, propeller and engine interactions in regular waves by a combination of experiment and simulation
PublicationAnalysis of hull, propeller and engine interactions in regular waves by a combination of experiment and simulation
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Immunosuppressive properties of amino acid and peptide derivatives of mycophenolic acid
PublicationMycophenolic acid (MPA) was coupled with amino acids and biologically active peptides including derivatives of tuftsin to modify its immunosuppressive properties. Both amino acid unit in the case of simple MPA amides and modifications within peptide moiety of MPA - tuftsin conjugates influenced the observed activity. Antiproliferative potential of the obtained conjugates was investigated in vitro and MPA amides with threonine methyl...
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Modifications at the C(5) position of pyrimidine nucleosides
PublicationThis review summarizes the state of knowledge on the chemical methods of C(5)-modifications of uridine and cytidine derivatives and may serve as a useful tool for synthetic chemists to choose an appropriate reaction protocol. The synthesis of 5-substituted uracil derivatives is gaining an increasing interest because of their possible applications in medicine and pharmacy. Modifications at the C(5) position of pyrimidine nucleosides...
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Novel 1,2,4-Oxadiazole Derivatives in Drug Discovery
PublicationAbstract: Five-membered 1,2,4-oxadiazole heterocyclic ring has received considerable attention because of its unique bioisosteric properties and an unusually wide spectrum of biological activities. Thus, it is a perfect framework for the novel drug development. After a century since the 1,2,4-oxadiazole have been discovered, the uncommon potential attracted medicinal chemists’ attention, leading to the discovery of a few presently...
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Recent progress in the development of steroid sulfatase inhibitors – examples of the novel and most promising compounds from the last decade
PublicationThe purpose of this review article is to provide an overview of recent achievements in the synthesis of novel steroid sulfatase (STS) inhibitors. STS is a crucial enzyme in the biosynthesis of active hormones (including estrogens and androgens) and, therefore, represents an extremely attractive molecular target for the development of hormone-dependent cancer therapies. The inhibition of STS may effectively reduce the availability...
Year 2019
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Framework of an Evolutionary Multi-Objective Optimisation Method for Planning a Safe Trajectory for a Marine Autonomous Surface Ship
PublicationThis paper represents the first stage of research into a multi-objective method of planning safe trajectories for marine autonomous surface ships (MASSs) involved in encounter situations. Our method applies an evolutionary multi-objective optimisation (EMO) approach to pursue three objectives: minimisation of the risk of collision, minimisation of fuel consumption due to collision avoidance manoeuvres, and minimisation of the extra...
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High performance super-twisting sliding mode control for a maritime autonomous surface ship (MASS) using ADP-Based adaptive gains and time delay estimation
PublicationThis research addresses two kinds of problems related to optimal trajectory tracking of a Maritime Autonomous Surface Ship (MASS): those caused by the time-varying external disturbances including winds, waves and ocean currents as well as those resulting from inherent dynamical uncertainties. As the paper shows, an accurate and robust optimal controller can successfully deal with both issues. An improved Optimal Adaptive Super-Twisting...
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New potent STS inhibitors based on fluorinated 4-(1-phenyl-1H-[1,2,3]triazol-4-yl)-phenyl sulfamates
PublicationA series of fluorinated analogs based on the frameworks of 4-(1- phenyl-1H-[1,2,3]triazol-4-yl)-phenyl sulfamates have been synthesized as steroid sulfatase (STS) inhibitors. The design of chemical structures of new potential STS inhibitors was supported by molecular docking techniques to identify potential interactions between inhibitors and amino acid residues located in the STS active site. The STS inhibitory potency was evaluated...
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Novel steroid sulfatase inhibitors based on N ‐thiophosphorylated 3‐(4‐aminophenyl)‐coumarin‐7‐O‐sulfamates
PublicationIn the present work, we described convenient methods for the synthesis ofN-thiophosphorylated 3-(4-aminophenyl)-coumarin-7-O-sulfamates as steroid sulfatase(STS) inhibitors. To design the structures of the potential STS inhibitors, molecularmodeling techniques were used. A computational docking method was used to deter-mine the binding modes of the synthesized inhibitors as well as to identify potentialinteractions between specified...
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The Analysis of Overall Ship Fuel Consumption in Acceleration Manoeuvre using Hull-Propeller-Engine Interaction Principles and Governor Features
PublicationThe problem of reduction of greenhouse gas emissions in shipping is currently addressed by many research works and related industries. There are many existing and visionary technologies and ideas, which are conceptually defined or practically realised. This goal can be achieved in different ways, and reducing fuel consumption is one of the major methods. In these circumstances, the aim of this study is to analyse the possibility...
Year 2018
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New Concept of Numerical Ship Motion Modelling for Total Ship Operability Analysis by Integrating Ship and Environment Under One Overall System
PublicationThe paper presents a new concept of overall ship motion modelling for application to total ship operability. The delivered model is a multi-phase and includes both submerged part of ship’s hull and the surrounding water as a unique body. The Discrete Finite Element Method is applied. The model is successfully examined and illustrated for a selected AHTS.
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Selected Methods for the Chemical Phosphorylation and Thiophosphorylation of Phenols
PublicationThis Focus Review gathers together a selection of methods for the chemical phosphorylation of phenols that employ three‐ and four‐coordinate phosphorus compounds. Phosphorylated scaffolds can exhibit enhanced properties compared to their non‐phosphorylated analogues, such as increased biological activity and increased/decreased solubility; as such, phosphorus compounds have gained more and more interest in organic and medicinal...
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Structural and mechanical properties of hydroxyapatite coatings formed by ion-beam assisted deposition
PublicationThe ion-beam assisted deposition (IBAD) is an advanced method capable of producing crystalline coatings at low temperatures. We determined the characteristics of hydroxyapatite Ca10(PO4)6(OH)2 target and coatings formed by IBAD using X-ray photoemission spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and energy dispersive X-ray (EDX). The composition of the coatings'...
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Synthesis and antimicrobial activity of amino acid and peptide derivatives of mycophenolic acid
PublicationThe series of 16 novel amino acid and peptide mycophenolic acid (MPA) derivatives was obtained as potential antibacterial agents. Coupling of MPA with respective amines was optimized with condensing reagents such as EDCI/DMAP and T3P/TEA. Amino acid analogs were received both as methyl esters and also with the free carboxylic group. The biological activity of the products was tested on five references bacterial strains: Klebsiella...
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The synthesis and structure of a potential immunosuppressant: N-mycophenoyl malonic acid dimethyl ester
PublicationThe synthesis of a potential immunosuppressant, i.e. dimethyl ester of N-mycophenoyl malonic acid was optimized in the reaction of mycophenolic acid (MPA) with amino malonic dimethyl ester in the presence of propanephosphonic anhydride (T3P) as a coupling reagent. The structural properties of the obtained MPA derivative were investigated by NMR, MS and single crystal X-ray diffraction methods. Theoretical considerations of conformational...
Year 2017
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Geometry optimization of steroid sulfatase inhibitors - the influence on the free binding energy with STS
PublicationIn the paper we review the application of two techniques (molecular mechanics and quantum mechanics) to study the influence of geometry optimization of the steroid sulfatase inhibitors on the values of descriptors coded their chemical structure and their free binding energy with the STS protein. We selected 22 STS-inhibitors and compared their structures optimized with MM+, PM7 and DFT B3LYP/6–31++G* approaches considering separately...
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Improvement of microstructure and mechanical properties of high dense sic ceramics manufactured by high-speed hot pressing
PublicationNon-oxide ceramics possess high physical-mechanical properties, corrosion and radiation resistance, which can be used as a protective materials for radioactive wastes disposal. The aim of the present study was the manufacturing of high density SiC ceramics with advanced physical and mechanical parameters. The high performance on the properties of produced ceramics was determined by the dense and monolithic structure. The densified...
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Synthesis and biological evaluation of fluorinated N-benzoyl and N-phenylacetoyl derivatives of 3-(4-aminophenyl)-coumarin-7-O-sulfamate as steroid sulfatase inhibitors
PublicationIn the present work, we report convenient methods for the synthesis of 3-(4-aminophenyl)-coumarin-7-O-sulfamate derivatives N-acylated with fluorinated analogues of benzoic or phenylacetic acid as steroid sulfatase (STS) inhibitors. The design of these potential STS inhibitors was supported by molecular modeling techniques. Additionally, computational docking methods were used to determine the binding modes of the synthesized inhibitors...
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Synthesis and biological evaluation of N-acylated tyramine sulfamates containing C-F bonds as steroid sulfatase inhibitors
PublicationSteroid sulfatase (STS) is responsible for the hydrolysis of biologically inactive sulfated steroids into their active un-sulfated forms and promotes the growth of various hormone-dependent cancers (e.g., breast cancer). Therefore, the STS enzyme is a promising therapeutic target for the treatment of steroid-sensitive cancers. Herein, we report the synthesis and biological evaluation of sulfamate analogs as potential STS inhibitors...
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TOTAL SHIP OPERABILITY – REVIEW, CONCEPT AND CRITERIA
PublicationThe ship operability can be understood and analysed in different manners, and its quality is described using different indexes by different authors. Practically, there is no general and widely accepted description of total ship operability in the literature, nor in the rules of classification societies, which would include both seakeeping and manoeuvrability characteristics of a ship, and simultaneously take into account all ship...
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Zirconia ceramics with additions of Alumina for advanced tribological and biomedical applications
PublicationThe results of an investigation on slip cast and sintered Y2O3 (3 wt%)- stabilized ZrO2 with additions of 5, 10, 15 wt% Al2O3 are reported. The surface roughness, porosity and density of the samples were measured. The hardness HRc and Hv, fracture toughness K1C, and friction coefficients were also measured using standard methods. The structural properties of the samples were observed by Scanning Electron Microscopy (SEM). The surface...
Year 2016
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Cavitation erosion resistance of thick CrC coating deposition by the Arc-PVD method
PublicationThe paper investigates the durability of chromium carbide (CrC) coatings, with thicknesses up to 20 μm, applied using the Arc-PVD technique, against cavitation erosion. The study employs the rotating disk testing method to evaluate the performance of these coatings. Findings indicate that the carbon content within the Cr-C coatings significantly influences their resistance to cavitation erosion, with variations ranging from 2 to...
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Convenient and efficient synthesis of functionalized unsymmetrical alkynyl sulfides
PublicationWe developed a simple and efficient method for the synthesis of functionalized unsymmetrical alkynyl sulfides under mild conditions in good yields. The designed method is based on the reaction of 5,5-dimethyl-2-thioxo-1,3,2-dioxaphosphorinan-2-disulfanyl derivatives with lithium acetylides. The developed method allows the preparation of unsymmetrical alkynyl sulfides bearing additional hydroxyl, carboxyl, or amino functionalities.
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Evaluation of adhesive forces and the specific surface energy of zirconia stabilized by yttria with alumina additions ceramic by AFM method
PublicationThe adhesive forces and the specific surface energy of ceramic material surfaces are very important for further tribological and biomedical applications of ceramics. Partially stabilized zirconia (zirconium oxide) is popular for manufacturing various medical products. ZrO2 stabilized by Y2O3 with additions of 5 wt% alumina was produced by slip casting method with a subsequent sintering. Structure and chemical composition of ceramic...
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Odporność kawitacyjna grubych powłok ochronnych CrC nanoszonych metodą niskociśnieniowego wyładowania łukowego (Arc-PVD)
PublicationReferat przedstawia analizę i metodę pokrywania powierzchni materiałów zastosowanych w turbinach parowych i śrubach okrętowych za pomocą CrC przy zastosowaniu metodę ARC-PVD. Celem jest podwyższenie trwałości powierzchni narażających na erozję wywołaną przez kawitację.
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Phosphoroorganic Metal Complexes in Therapeutics
PublicationThe present mini-review highlights recent developments on antitumor activity of metal-based therapeutics which have been a subject of researches for the last few decades. In 1965, Rosenberg found that during an electrolysis on platinum electrodes a complex of Pt is generated which inhibited to a great extent a binary fission in Escherichia coli bacteria. This discovery started a new chapter in medicinal chemistry and the interesting...
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Selected organophosphorus compounds with biological activity. Applications in medicine
PublicationThe purpose of this article is to provide an overview of the latest applications of organophosphorus compounds (OPs) that exhibit biological activity. A large family of OPs have become popular in recent years. The practical application of OPs in modern medicine has been attributed to their unique properties. In this article, the methods used to select these compounds will be emphasized. This paper will first outline the findings...
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Synthesis and biological evaluation of fluorinated 3-phenylcoumarin-7-O-sulfamate derivatives as steroid sulfatase inhibitors
PublicationIn the present work, we report the initial results of our study on a series of 3-phenylcoumarin sulfamate-based compounds containing C-F bonds as a novel inhibitors of steroid sulfatase (STS). The new compounds are potent STS inhibitors, possessing more than 10 times higher inhibitory potency than coumarin-7-O-sulfamate. In the course of our investigation, compounds 2b and 2c demonstrated the highest inhibitory effect in the enzymatic...
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Synthesis and steroid sulfatase inhibitory activities of N-phosphorylated 3-(4-aminophenyl)-coumarin-7-O-sulfamates
PublicationIn the present work, we report convenient methods for the synthesis and biological evaluation of N-phosphorylated derivatives of 3-(4-aminophenyl)-coumarin-7-O-sulfamate as potential steroid sulfatase (STS) inhibitors. Their binding modes were modeled using docking techniques. The inhibitory effects of the synthesized compounds were tested on STS isolated from human placenta. All of the newly synthesised coumarin derivatives were...
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ОПРЕДЕЛЕНИЕ КОЭФФИЦИЕНТА ТРЕНИЯ ПОКРЫТИЙ НА ОСНОВЕ НИТРИДА МОЛИБДЕНА МЕТОДОМ ОСЦИЛЛИРУЮЩЕЙ МИКРОТРИБОМЕТРИИ
PublicationМетодом осциллирующей микротрибометрии на базе атомно-силавой микроскопии (АСМ) выполнены измерения коэффициента трения износостойких цокрытий на основе нитрида молибдена: Mo2N и системыMo(C)N, осажденных на стальную подложку. Получены значения коэффициента трения для серии покрытий нитрида молибдена, а также серии покрытий нитрида молибдена с добавлением углерода. Содержание в покрытии нитрида молибдена 7% углерода приводит к...
Year 2015
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DDQ-mediated synthesis of functionalized unsymmetrical disulfanes
PublicationWe developed a simple and efficient method for the synthesis of functionalized unsymmetrical disulfanes under mild conditions in good yields. The designed method is based on the reaction of bis(5,5- dimethyl-2-thioxo-1,3,2-dioxaphosphorinan-2-yl)disulfane with thiols in the presence of 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ). The developedmethod allows the preparation of unsymmetrical disulfanes bearing additional hydroxy, carboxy,...
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DRONY - Nowy sposób na rejestrację danych fotogrametrycznych
PublicationDrony wyposażone w lekkie aparaty fotograficzne lub kamery umożliwiają skanowanie, pomiary i generowanie modeli 3D danego obszaru na podstawie zdjęć rejestrowanych z powietrza. Zapewniają przy tym większą elastyczność oraz niższe koszty eksploatacji i obciążane są mniejszym ryzykiem niż pilotowe samoloty i helikoptery. Artykuł przedstawia możliwości wykorzystania dronów pracach związanych z rejestracją danych fotogrametrycznych.