2021 - Repozytorium publikacji - Politechnika Gdańska

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DETERMINATION OF THE AERODYNAMIC DRAG OF PNEUMATIC LIFE RAFTS AS A FACTOR FOR INCREASING THE RELIABILITY OF RESCUE OPERATIONS
- Edyta Ksiązkiewicz
- Jacek Jachowski
- Izabela Szwoch
2021 Pełny tekst Polish Maritime Research
Ensuring the safety of ship crews at sea is of the utmost importance. Life rafts are one of the basic components of any seagoing vessel and ensuring their stability is an important component of maritime research. This study concerns the determination of the aerodynamic drag coefficients of pneumatic life rafts in a full range of wind speed and directions. The drag coefficients are based on full-scale experimental studies and numerical calculations (computational fluid dynamics) carried out with Flow-3D software. Two types of life rafts are analysed in the numerical simulations, namely, a non-deformed raft and a raft deformed under the influence of wind pressure at a given flow velocity. The shape of the deformed pneumatic life raft is recreated on the basis of photographic documentation from experimental studies. The results of the numerical calculations are verified on the basis of full-scale flow experiments carried out at the Low Speed Wind Tunnel T-3 Laboratory at the Institute of Aviation in Warsaw. This study shows that there is a dependence of aerodynamic drag on the degree of deformation of the above-water part of the life raft, as well as the angle of the raft setting to the wind. In real water conditions, this angle depends mainly on the anchor point of the drift anchor and therefore should be considered at the design stage, which will directly reduce the wind leeway of the raft.
Determination of the refractive index and wavelength‐dependent optical properties of few‐layer CrCl3 within the Fresnel formalism
- Shafaq Kazim
- Roberto Gunnella
- Marco Zannotti
- Rita Giovannetti
- Tomasz Klimczuk
- Luca Ottaviano
2021 Pełny tekst JOURNAL OF MICROSCOPY
Based on previous reports on the optical microscopy contrast of mechanically exfoliated few layer CrCl3 transferred on 285 nmand 270 nmSiO2 on Si(100), we focus on the experimental determination of an effective mean complex refractive index via a fitting analysis based on the Fresnel equations formalism. Accordingly, the layer and wavelength-dependent absorbance and reflectance are calculated. Layer and wavelength-dependent optical contrast curves are then evaluated demonstrating that the contrast is significantly high only around welldefined wavelength bands. This is validated a posteriori, by experimental UVVis absorbance data. The present study aims to show the way towards the most reliable determination of thickness of the 2D material flakes during exfoliation.
Determination of the Theoretical and Actual Working Volume of a Hydraulic Motor—Part II (The Method Based on the Characteristics of Effective Absorbency of the Motor)
- Paweł Śliwiński
2021 Pełny tekst ENERGIES
: In this article, the second method of determination of the theoretical and actual working volume of a hydraulic motor is described. The proposed new method is based on the characteristics of effective absorbency of the motor. The effective absorbency has been defined as the ratio of flow rate in a motor to the rotational speed of the motor’s shaft. It has been shown that the effective absorbency is a nonlinear function of the rotational speed and nonlinear function of the pressure drop in the motor’s working chambers. Furthermore, it has been proven that the actual working volume of a motor is a function of a third degree of pressure drop in the motor’s working chamber. The actual working volume should be taken to assess the mechanical and volumetric energy losses in the motor. Furthermore, the influence of the flowmeter location in the measurement system and the compressibility of liquid on the result of the theoretical and actual working volume calculation was also taken into account and is described in this article. The differences in the assessment of the volumetric efficiency assuming the theoretical and actual working volume was also shown.
Determining horizontal curvature of railway track axis in mobile satellite measurements
- Władysław Koc
- Andrzej Wilk
- Cezary Specht
- Krzysztof Karwowski
- Jacek Skibicki
- Krzysztof Czaplewski
- Sławomir Judek
- Piotr Chrostowski
- Jacek Szmagliński
- Paweł Dąbrowski
- Mariusz Specht
- Sławomir Grulkowski
- Roksana Licow
2021 Pełny tekst Bulletin of the Polish Academy of Sciences-Technical Sciences
The article discusses the applicability of a novel method to determine horizontal curvature of the railway track axis based on results of mobile satellite measurements. The method is based on inclination angle changes of a moving chord in the Cartesian coordinate system. In the presented case, the variant referred to as the method of two virtual chords is applied which consists in manoeuvring with only one GNSS (Global Navigation Satellite System) receiver. The assumptions of the novel method are formulated, and the assessment of its application in the performed campaign of mobile satellite measurements is given. The shape of the measured railway axis is shown in the national spatial reference system PL-2000, and the speed of the measuring trolley during the measurement is calculated based on the recorded coordinates. It has been observed that over the test section, the curvature ordinates differ from the expected waveform, which can be caused by disturbances of the measuring trolley trajectory. However, this problem can easily be overcome by filtering the measured track axis ordinates to obtain the correct shape – this refers to all track segments: straight sections, circular arcs, and transition curves. The virtual chord method can also be the basis for assessing the quality of the recorded satellite signal. The performed analysis has shown high accuracy of the measuring process.
Determining the Seasonal Variability of the Territorial Sea Baseline in Poland (2018–2020) Using Integrated USV/GNSS/SBES Measurements
- Mariusz Specht
- Cezary Specht
- Andrzej Stateczny
- Łukasz Marchel
- Oktawia Lewicka
- Monika Paliszewska-Mojsiuk
- Marta Wiśniewska
2021 Pełny tekst ENERGIES
The Territorial Sea Baseline (TSB) allows coastal states to define the maritime boundaries, such as: contiguous zone, continental shelf, exclusive economic zone and territorial sea. Their delimitations determine what rights (jurisdiction and sovereignty) a given coastal state is entitled to. For many years, the problem of delimiting baseline was considered in two aspects: legal (lack of clear-cut regulations and different interpretations) and measurement (lack of research tools for precise and reliable depth measurement in ultra-shallow waters). This paper aimed to define the seasonal variability of the TSB in 2018–2020. The survey was conducted in three representative waterbodies of the Republic of Poland: open sea, river mouth and exit from a large port, differing between each other in seabed shape. Baseline measurements were carried out with Unmanned Surface Vehicles (USV), equipped with Global Navigation Satellite System (GNSS) geodetic receivers and miniature Single Beam Echo Sounders (SBES). The survey has shown that the smallest seasonal variability of TSB (1.86–3.00 m) was confirmed for the waterbody located near the Vistula ´Smiała River mouth, which features steep shores. On the other hand, the greatest variability in the baseline (5.73–8.37 m) as observed in the waterbody adjacent to the public beach in Gdynia. Factors conditioning considerable changes in TSB determination were: periodically performed land reclamation works in the area and the fact that the depth of the waterbody increases slowly when moving away from the coastline.
Detoxification of the tricyclic antidepressant opipramol and its analog – IS-noh by UGT enzymes before and after activation by phase I enzymes in rat liver microsomes
- Anna Mieszkowska
- Koleta Hemine
- Anna Skwierawska
- Ewa Augustin
- Zofia Mazerska
2021 Pełny tekst CHEMICAL PAPERS
The present studies were carried out to evaluate the simultaneous one-pot metabolism of opipramol (IS-opi) and analog (IS-noh) by phase I and phase II enzymes present in rat liver microsomes (RLM) as an alternative to separate testing with recombinant enzymes. This approach allows for more time-saving and cost-effective screening of the metabolism of newly discovered drugs. We also considered that the lack of results for phase II, including UGT, often creates problems in correct selection of valuable compounds. Moreover, microsomes data set is richer in the contest and provides medical scientist to determine also the susceptibility of drugs to undergo phase I and then phase II. In the present work, we have shown that IS-noh was metabolized in vitro by phase I enzymes to the oxidation product, which was next transformed with UGTs to glucuronide. The results showed also that the previously known oxidation product of opipramol was changed to previously no reported glucuronidation product by UDP-glucuronosyltransferases. In addition, unlike IS-noh, opipramol did not prove to be the substrate for UGTs. Therefore, tricyclic antidepressants depending on the structure can trigger a different response after contact with UGT enzymes. Some will metabolize directly with UGTs, others only after activation by phase I enzymes.
Developing Methods for Building Intelligent Systems of Information Resources Processing Using an Ontological Approach
- Vasyl Lytvyn
- Victoria Vysotska
- Myroslava Bublyk
- Piotr Grudowski
- Yurii Matseliukh
- Roman Nanivskyi
2021 Advances in Intelligent Systems and Computing
The problem of developing methods of information resource processing is investigated. A formal procedure description of processing text content is developed. A new ontological approach to the implementation of business processes is proposed. Consider that the aim of our work is to develop methods and tools for building intelligent systems of information resource processing, the core of knowledge bases of which are ontology’s, and improve the efficiency of such systems by adapting ontology to the specifics of the subject area. The proposed approach is aimed at solving such problems: Analysis of the specifics and methods of building intelligent systems of information resource processing by classifying them according to the principle and space of functioning, which will distinguish the types of such systems depending on the mathematical support of their functioning; Development of mathematical models and methods of functioning of various classes of intelligent systems of information resource processing, the core of knowledge bases which is ontology, to study the effectiveness of such systems; Development of methods and algorithms of ontology adaptation to the specific tasks of the subject area in order to improve the efficiency of intelligent systems of information resources processing within this subject area; Definition of characteristics of quality of intellectual systems of processing of information resources and criteria of optimization of ontology’s as a part of their knowledge bases for increase of indicators of efficiency of functioning of such systems. The methods and tools will be used to build modern applied intelligent systems of information resource processing, the core of knowledge bases which are ontology’s, in such subject areas as management and maintenance of information resources on the Internet, during the construction of systems on-line and off-line content implementation, cloud storage, cloud computing, in the military and legal sphere. The expansion of the areas of application of the designed and developed intelligent systems of information resource processing based on ontology’s will help to overcome social, organizational, methodological and psychological barriers that arise as a reaction to the introduction of innovative approaches to the conduct of activities in the relevant sectors of the economy and regulatory spheres of functioning.
Development and validation of a method for the simultaneous analysis of fatty acid ethyl esters, ethyl sulfate and ethyl glucuronide in neonatal meconium: application in two cases of alcohol consumption during pregnancy
- Mateusz Woźniak
- Laura Banaszkiewicz
- Justyna Aszyk
- Marek Wiergowski
- Iwona Jańczewska
- Jolanta Wierzba
- Agata Kot-Wasik
- Marek Biziuk
2021 Pełny tekst ANALYTICAL AND BIOANALYTICAL CHEMISTRY
Alcohol consumption during pregnancy constitutes one of the leading preventable causes of birth defects and neurodevelopmental disorders in the exposed children. Fatty acid ethyl esters (FAEEs), ethyl glucuronide (EtG) and ethyl sulfate (EtS) have been studied as potential biomarkers of alcohol consumption. However, most analytical approaches proposed for their analysis in meconium samples consist of separated extraction procedures requiring the use of two meconium aliquots, which is costly in terms of both time and materials. Therefore, the aim of this study was to develop and validate a method for the simultaneous extraction of 9 FAEEs, EtG and EtS from one meconium aliquot. The sample was homogenized using methanol, and then FAEEs were extracted with hexane while EtG and EtS were isolated using acetonitrile. Then, extracts were applied to solid-phase extraction columns and analysed by gas chromatography mass spectrometry (FAEEs) and liquid chromatography tandem mass spectrometry (EtG and EtS). Calibration curves were linear with r values greater than 0.99. The LODs ranged from 0.8 to 7.5 ng/g for FAEEs and were 0.2 ng/g and 0.8 ng/g for EtS and EtG, respectively. LOQs ranged from 5 to 25 ng/g for FAEEs and were 1 ng/g and 2.5 ng/g for EtS and EtG, respectively. Accuracies and precisions were between 93.8 and 107% and between 3.5 and 9.7%, respectively. The recovery values ranged from 89.1 to 109%. The method proved to be sensitive, specific, simple and fast and allowed for the reduction of the amount of organic solvent used for extraction compared to other published data while higher recoveries were obtained. The method was used for analysis meconium samples in two cases of mothers who were consuming alcohol during pregnancy.
Development, characterization and evaluation of composite adsorbent for the adsorption of crystal violet from aqueous solution: Isotherm, kinetics, and thermodynamic studies
- Mohamed Sulyman
- Justyna Kucińska-Lipka
- Maciej Sienkiewicz
- Andrzej Gierak
2021 Pełny tekst Arabian Journal of Chemistry
The purpose of this work focuses on the production and investigations of a new composite material as alternative low-cost adsorbent for the removal of crystal violet (CV) dye from waste solution. The production method was performed by in-situ thermal activation technology via extrusion process of polymer wastes containing tire rubber (50 wt%) and polyurethane foam (50 wt%) using single-screw extruder under processing temperature of 180 °C and shearing rate 100 rpm. The physico-chemical properties of the materials obtained were examined such as bulk density, zero surface charge (pHpzc), Brunauer-Emmett-Teller (BET) surface area, as well as samples tested by infrared absorption spectroscopy (FT-IR), scanning electron microscopy (SEM). X-ray fluorescence spectroscopy (WD-XRF). Thermogravimetric analysis (TGA). These techniques were additionally applied to the full characteristics of the composite materials obtained. The impacts of solution pH (3.0–9.0), adsorbent dosage (0.1–1.0 g) and initial adsorbate concentration (in range 10 –90 mg/l) on adsorption capacity of the investigated adsorbent were studied. From our investigation we found that adsorption equilibrium was achieved within 200 min. The maximum monolayer adsorption capacity (qmax) for our composite adsorbent were obtained from the Langmuir equation and equaled 20.92 mg/g. Mathematical analysis has shown that the pseudo second kinetic model of the order describes the kinetics of the adsorption process well.
Development of a tropical disease diagnosis system using artificial neural network and GIS
- Paweł Cieszko
- Marcin Kulawiak
- Natalia Kulawiak
- Katarzyna Sikorska
- Aleksander Stojanowski
- Paweł Goławski
2021
Expert systems for diagnosis of tropical diseases have been developed and implemented for over a decade with varying degrees of success. While the recent introduction of artificial neural networks has helped to improve the diagnosis accuracy of such systems, this aspect is still negatively affected by the number of supported diseases. A large number of supported diseases usually corresponds to a high number of overlapping symptoms, which results in a considerable drop in diagnosis accuracy. This is particularly important when diagnosing patients returning from holiday or business trips which took them through a number of different tropical regions. The paper presents a system dedicated to diagnosis of patients returning from various tropical countries. The system integrates an artificial neural network with a Geographic Information System (GIS) in order to enhance the diagnostic process. As a result, the system provides several layers of diagnosis support, depending on the types and number of provided patient characteristics. The system has been developed in cooperation with the University Center of Maritime and Tropical Medicine located in the city of Gdynia in northern Poland and applied to diagnosis of patients with malaria, dengue and stechiostomasis with promising results.
Development of Gas Sensor Array for Methane Reforming Process Monitoring
- Dominik Dobrzyniewski
- Bartosz Szulczyński
- Tomasz Dymerski
- Jacek Gębicki
2021 Pełny tekst SENSORS
The article presents a new method of monitoring and assessing the course of the dry methane reforming process with the use of a gas sensor array. Nine commercially available TGS chemical gas sensors were used to construct the array (seven metal oxide sensors and two electrochemical ones). Principal Component Regression (PCR) was used as a calibration method. The developed PCR models were used to determine the quantitative parameters of the methane reforming process: Inlet Molar Ratio (IMR) in the range 0.6–1.5, Outlet Molar Ratio (OMR) in the range 0.6–1.0, and Methane Conversion Level (MCL) in the range 80–95%. The tests were performed on model gas mixtures. The mean error in determining the IMR is 0.096 for the range of molar ratios 0.6–1.5. However, in the case of the process range (0.9–1.1), this error is 0.065, which is about 6.5% of the measured value. For the OMR, an average error of 0.008 was obtained (which gives about 0.8% of the measured value), while for the MCL, the average error was 0.8%. Obtained results are very promising. They show that the use of an array of non-selective chemical sensors together with an appropriately selected mathematical model can be used in the monitoring of commonly used industrial processes.
Development of globalization in culture on the example of Europe
- Monika Hadaś-dyduch
- Sebastian Wilczewski
2021
This article attempts to reflect on the consequences of cultural globalization i.e. the opporturnities and threats that exist it brings with it for existing local cultures. As we know, The processes of globalization contribute to the emergence of any, often contradictory phenomena in the field of culture which influence the existing local cultural systems in various ways. It is assumed that the most important consequence of cultural globalization is the increased contact of different cultures, thanks to which certain cultural elements are mixed disseminated and sometimes rnade similar. The study was based on the countries belonging to Europe. The aim of the study is to identify couritries most similar to Poland in the development of cultural globalization. The study used an algorithm based on the wavelet transform and DTW. The DTW algorithm was used in the study because it is extremely effective in measuring the similarity of signials in the time domain. It minimizes the effects of shifting and distorting signals through "flexible" transformation of the time signal which allows you to find similar shapes with different phases.
Development of Microstructured Carbon Coatings by Substrate-Catalytic CVD
- Mattia Pierpaoli
- Mirosław Sawczak
- Anna Dettlaff
2021 Pełny tekst Coatings
Carbon nanostructured films were synthesized by chemical vapor deposition (CVD) on H18 stainless steel (AISI 440C) sheets with an H2/CH4/N2 gas mixture at various substrate temperatures. During the synthesis, the iron and chromium oxide layer was formed between the steel and carbonaceous layer. The carbon films exhibited wall-like and spherical morphologies and structures, as characterized by scanning electron microscopy and Raman spectroscopy. It was found that the synthesis temperature affects the microsphere density and, therefore, also in the electrochemical behavior. The electrochemical behavior of nanostructured carbon coatings strongly depends on the CVD deposition conditions. The best corrosion resistance (Rp = 11.8 MΩ·cm2, Icorr = 4.4 nA·cm−2) exhibits a nanostructured carbon sample with a moderate amount of sp2-C-rich carbon microspheres CμSs synthesized at 700 °C. The corrosion resistance of the nanostructured carbon coating is better than raw stainless steel.
Development of Strategies for AOB and NOB Competition Supported by Mathematical Modeling in Terms of Successful Deammonification Implementation for Energy-Efficient WWTPs
- Mehdi Sharifshourjeh
- Przemysław Kowal
- Lu Xi
- Li Xie
- Jakub Drewnowski
2021 Pełny tekst Processes
Novel technologies such as partial nitritation (PN) and partial denitritation (PDN) could be combined with the anammox-based process in order to alleviate energy input. The former combination, also noted as deammonification, has been intensively studied in a frame of lab and full-scale wastewater treatment in order to optimize operational costs and process efficiency. For the deammonification process, key functional microbes include ammonia-oxidizing bacteria (AOB) and anaerobic ammonia oxidation bacteria (AnAOB), which coexisting and interact with heterotrophs and nitrite oxidizing bacteria (NOB). The aim of the presented review was to summarize current knowledge about deammonification process principles, related to microbial interactions responsible for the process maintenance under varying operational conditions. Particular attention was paid to the factors influencing the targeted selection of AOB/AnAOB over the NOB and application of the mathematical modeling as a powerful tool enabling accelerated process optimization and characterization. Another reviewed aspect was the potential energetic and resources savings connected with deammonification application in relation to the technologies based on the conventional nitrification/denitrification processes
Developments in Miniaturization of Gas Chromatography
- Waldemar Wardencki
- Zygfryd Witkiewicz
2021
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DFT study of low-energy electron interaction with pyridine, pyrazine and their halo derivatives
- Natalia Tańska
2021 Pełny tekst EUROPEAN PHYSICAL JOURNAL D
In this work, the density functional theory with B3LYP hybrid functional was employed to calculate quantities useful for estimating the behavior of pyridine, pyrazine and their derivatives monosubstituted with Cl or Br atom, when exposed to low-energy electron impact. Vertical electron affinities obtained in several Pople basis sets and in aug-cc-pVTZ basis set are reported. Although some of the investigated molecules do not form stable anions, the results are in a satisfactory agreement with the available, albeit sparse experimental data, if the diffuse functions are included in calculations. It was found that the 6-31+G* basis is sufficient and its further enlargement does not significantly change the results. At this level of theory, potential energy curves, supported by enthalpies of dissociation to the neutral and anion fragment, were also determined for the description of the dissociative electron attachment. According to B3LYP, the potential energy curves of the halogen bond are almost repulsive in halopyridines, whereas halopyrazine anions require small activation energy for dissociation. Vertical electron affinities, enthalpies and equilibrium C-X distances (X=H, Cl, Br) were also calculated using Møller-Plesset second-order perturbation theory.
Diagnostic Accuracy of Liquid Biopsy in Endometrial Cancer
- Marta Łukasiewicz
- Krzysztof Pastuszak
- Sylwia Łapińska-Szumczyk
- Robert Różański
- Sjors In ’t Veld
- Michał Bieńkowski
- Tomasz Stokowy
- Magdalena Ratajska
- Myron G Best
- Thomas Würdinger
- Anna Żaczek
- Anna Supernat
- Jacek Jassem
2021 Pełny tekst Cancers
Background: Liquid biopsy is a minimally invasive collection of a patient body fluid sample. In oncology, they offer several advantages compared to traditional tissue biopsies. However, the potential of this method in endometrial cancer (EC) remains poorly explored. We studied the utility of tumor educated platelets (TEPs) and circulating tumor DNA (ctDNA) for preoperative EC diagnosis, including histology determination. Methods: TEPs from 295 subjects (53 EC patients, 38 patients with benign gynecologic conditions, and 204 healthy women) were RNA-sequenced. DNA sequencing data were obtained for 519 primary tumor tissues and 16 plasma samples. Artificial intelligence was applied to sample classification. Results: Platelet-dedicated classifier yielded AUC of 97.5% in the test set when discriminating between healthy subjects and cancer patients. However, the discrimination between endometrial cancer and benign gynecologic conditions was more challenging, with AUC of 84.1%. ctDNA-dedicated classifier discriminated primary tumor tissue samples with AUC of 96% and ctDNA blood samples with AUC of 69.8%. Conclusions: Liquid biopsies show potential in EC diagnosis. Both TEPs and ctDNA profiles coupled with artificial intelligence constitute a source of useful information. Further work involving more cases is warranted.
DIAGNOSTIC INFORMATION ANALYSIS OF QUICKLY CHANGING TEMPERATURE OF EXHAUST GAS FROM MARINE DIESEL ENGINE PART I SINGLE FACTOR ANALYSIS
- Patrycja Puzdrowska
2021 Pełny tekst Polish Maritime Research
In this paper, attention was paid to the problem of low controllability of marine medium- and high-speed engines during operation, which significantly limits the parametric diagnosis. The measurement of quickly changing temperature of engine exhaust gas was proposed, the courses of which can be a source of diagnostic information. The F statistic of the Fisher-Snedecor distribution was chosen as a statistical tool. Laboratory tests were carried out on the bench of a Farymann Diesel engine. The tests consisted of introducing the real changes in the constructional structure of the considered functional systems of the engine. Three changed parameters for the structure were reviewed: the active cross-sectional area of the inlet air channel, injector opening pressure and compression ratio. Based on the recorded plots of the quick-changing temperatures of the exhaust gases, three diagnostic measures were defined and subjected to statistical tests. The following data were averaged over one cycle for a 4-stroke piston engine operation, (1) the peak to peak value of the exhaust gas temperature, (2) the specific enthalpy of the exhaust gas, and (3) the rate of increase and decrease in the values for the quick-changing exhaust gas temperature. In this paper will present results of the first stage of the elimination study: the one-factor statistical analysis (randomised complete plan). The next part will present the results of the second stage of studies: two-factor analysis (block randomised plan), where the significance of the effect of changing the values of the structure parameters on the diagnostic measures was analysed in the background of a variable engine load.
Diamond Nanofilm Normalizes Proliferation and Metabolism in Liver Cancer Cells
- Malwina Sosnowska
- Marta Kutwin
- Barbara Strojny
- Mateusz Wierzbicki
- Dominik Cysewski
- Jarosław Szczepaniak
- Mateusz Ficek
- Piotr Koczoń
- Sławomir Jaworski
- André Chwalibog
- Ewa Sawosz
2021 Pełny tekst Nanotechnology Science and Applications
Purpose: Surgical resection of hepatocellular carcinoma can be associated with recurrence resulting from the degeneration of residual volume of the liver. The objective was to assess the possibility of using a biocompatible nanofilm, made of a colloid of diamond nanoparticles (nfND), to fill the side after tumour resection and optimize its contact with proliferating liver cells, minimizing their cancerous transformation. Methods: HepG2 and C3A liver cancer cells and HS-5 non-cancer cells were used. An aqueous colloid of diamond nanoparticles, which covered the cell culture plate, was used to create the nanofilm. The roughness of the resulting nanofilm was measured by atomic force microscopy. Mitochondrial activity and cell proliferation were measured by XTT and BrdU assays. Cell morphology and a scratch test were used to evaluate the invasiveness of cells. Flow cytometry determined the number of cells within the cell cycle. Protein expression in was measured by mass spectrometry. Results: The nfND created a surface with increased roughness and exposed oxygen groups compared with a standard plate. All cell lines were prone to settling on the nanofilm, but cancer cells formed more relaxed clusters. The surface compatibility was dependent on the cell type and decreased in the order C3A >HepG2 >HS-5. The invasion was reduced in cancer lines with the greatest effect on the C3A line, reducing proliferation and increasing the G2/M cell population. Among the proteins with altered expression, membrane and nuclear proteins dominated. Conclusion: In vitro studies demonstrated the antiproliferative properties of nfND against C3A liver cancer cells. At the same time, the need to personalize potential therapy was indicated due to the differential protein synthetic responses in C3A vs HepG2 cells. We documented that nfND is a source of signals capable of normalizing the expression of many intracellular proteins involved in the transformation to non-cancerous cells.
Diaryl Sulfide Derivatives as Potential Iron Corrosion Inhibitors: A Computational Study
- Morad El-Hendawy
- Asmaa Kamel
- Mohamed Mahmoud
- Rabah Boukherroub
- Jacek Ryl
- Mohammed Amin
2021 Pełny tekst MOLECULES
The present work aimed to assess six diaryl sulfide derivatives as potential corrosion inhibitors. These derivatives were compared with dapsone (4,4′-diaminodiphenyl sulfone), a common leprosy antibiotic that has been shown to resist the corrosion of mild steel in acidic media with a corrosion efficiency exceeding 90%. Since all the studied compounds possess a common molecular backbone (diphenyl sulfide), dapsone was taken as the reference compound to evaluate the efficiency of the remainder. In this respect, two structural factors were examined, namely, (i) the effect of replacement of the S-atom of diaryl sulfide by SO or SO2 group, (ii) the effect of the introduction of an electron-withdrawing or an electron-donating group in the aryl moiety. Two computational chemical approaches were used to achieve the objectives: the density functional theory (DFT) and the Monto Carlo (MC) simulation. First, B3LYP/6-311+G(d,p) model chemistry was employed to calculate quantum chemical descriptors of the studied molecules and their geometric and electronic structures. Additionally, the mode of adsorption of the tested molecules was investigated using MC simulation. In general, the adsorption process was favorable for molecules with a lower dipole moment. Based on the adsorption energy results, five diaryl sulfide derivatives are expected to act as better corrosion inhibitors than dapsone.