bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanistic Insights into GTP Hydrolysis by the RhoA Protein: Catalytic Impact of Glutamine Tautomerism
Authors: Pardos Jorge , García-Martínez Adrián , Ruiz-Pernia J. Javier , Tuñón Iñaki
Published: November 2024

We present a systematic evaluation of different possible reaction mechanisms for GTP hydrolysis in RhoA, a member of the Ras superfamily of enzymes that uses this reaction to switch from an active to an inactive conformation. These enzymes are activated by the presence of GTPase activating protein (or GAP) that forms an intimate complex with residues of the two proteins present in the active site. We have explored the multidimensional reactional free energy landscape in the active site of the complex formed by RhoA and p50RhoGAP. Our Molecular Dynamics simulations show that the activating enzyme p50RhoGAP establishes catalytically important interactions with the phosphate groups of GTP through its so-called arginine finger (Arg85) and also with RhoA residue Gln63. This is a key residue because it does not only interact with the nucleophilic water molecule but also participates actively in the reaction mechanism. Adaptive String Method simulations using hybrid QM/MM potentials with both Tight-Binding and Density Functional hamiltonians show that GTP hydrolysis proceeds through formation of a metaphosphate metastable species. Mechanistic proposals differ in the proton transfer rearrangements required to form the inorganic phosphate ion. Our simulations discard a solvent assisted mechanism and point to the participation of Gln63 in the proton transfer process by means of the side chain tautomerism from the amide to the imide form. The proton transfer required to recover the amide form of Gln63 requires the participation of the inorganic phosphate and it is the rate-limiting step of the process, with a free energy barrier of 20.2 kcal mol-1 at the B3LYPD3/MM level, in good agreement with the experimentally derived value. The amide-imide tautomerism could be relevant also in other enzymes, facilitating proton transfer events in complex mechanisms.
Equations and Electrochemical Methods for Measuring the Interfacial Charge-Transfer Kinetics of Li-ion Battery Active Materials at High Current Densities
Authors: Scanlan Kevin , Manthiram Arumugam
Published: November 2024

Experimental measurements and quantitative models of the interfacial charge-transfer kinetics of Li-ion battery (LIB) active materials (AM) are essential for accurate predictions of LIB rate performance, safety, and lifetime. The Butler-Volmer (BV) equation is commonly used to describe interfacial kinetics in LIBs as a function of the transfer coefficient (α) and exchange current (I0). It is tacitly assumed that α ≈ 0.5, so experimental measurements of α for LIB AMs have rarely been attempted. In this work, mathematical models are derived to fit the apparent α and I0 values from the electrochemical data at high current densities by reformulating the BV equation to describe the current dependence of charge-transfer resistance (Rct) and differential charge-transfer resistance (R’ct). Pseudo-steady-state extrapolation chronopotentiometry (S3E-CP), large-amplitude galvano EIS (LA-GEIS), and operando galvano EIS (O-GEIS) techniques are developed, and each is shown to be capable of accurately and precisely measuring the values of α and I0 while maintaining the conditions of stability, stationarity, and linearity. Symmetric coin cells are demonstrated as a simple and widely accessible tool for achieving the most accurate kinetic measurements, and preliminary results are reported for LiCoO2 symmetric cells at 50% state-of-charge. S3E-CP and LA-GEIS measurements yield apparent α values of, respectively, 0.420 and 0.431, while O-GEIS measurements show that these data are consistent with a two-step reaction with α1 = 0.5 and α2 = 3. The equations and electrochemical methods developed herein are broadly applicable for empirically measuring and modeling the interfacial charge-transfer kinetics in rechargeable batteries.
A pH-Responsive Synthetic Module Derived from Alanine to Encapsulate Toxic Dye from Wastewater.
Authors: Dolui Subrata
Published: November 2024

A pH-responsive amphiphilic poly(L-alanine acrylamide)-block-poly( methylmethacrylate (PAAla-b-PMMA) diblock copolymer biohybrids, based on hydrophilic PAAla and hydrophobic PMAA segments, is developed via direct switching from atom transfer radical polymerization. EbiB was used to mediate RDRP of a DL-alanine derived monomer, AAla, yielding a series of (PAAla-b-PMAA)-The copolymer's stimuli response has been assessed against pH. The translation of this structure into a synthetic polymer was the aim of this investigation. The copolymer is capable of switching between its among zwitterionic, anionic and cationic forms and this copolymer is capable of removal of toxic dye from wastewater. This approach not only enhances the effectiveness of dye removal but also contributes to the development of eco-friendly and recyclable materials for water purification applications.
The Relationship between Chronotype and Academic Achievement among Slovene University Students: The Mediating Role of Trait Self-Control and Sleep Quality
Authors: Maučec Katarina , Štukovnik Vita
Published: November 2024

Several studies have identified a relationship between an individual’s chronotype and academic performance. Specifically, individuals with a morning preference often outperform those with an evening preference. Our research explored whether trait self-control and sleep quality mediate this association. We conducted an online survey completed by Slovenian university students. Chronotype, trait self-control, and sleep quality were measured using the Morningness-Eveningness Questionnaire, the Brief Self-Control Scale, and the Pittsburgh Sleep Quality Index. Additionally, the participants’ academic achievement was assessed using an objective measure (the average grade for the winter 2022/2023 exam period) and a subjective measure (students’ own assessment of their performance compared to their peers). The results show that all researched concepts are positively correlated. Additionally, mediation analyses revealed that trait self-control significantly mediated the relationship between chronotype and both measures of academic achievement. Conversely, while sleep quality did not mediate the relationship between chronotype and objective academic achievement, it did partially mediate the relationship between chronotype and the subjective achievement measure. These insights provide a novel comprehension of the intrinsic modalities that might link chronotype and academic performance.
Constraining Logarithmic f(R, T) Model Using Dark Energy Density Parameter Ω_Λ and Hubble parameter H_0
Authors: Deb Biswajit , Deshamukhya Atri
Published: November 2024

Of many extended theories of gravity, f(R, T) gravity has gained reasonable interest in recent times as it provides interesting results in cosmology. Logarithmic corrections in modified theories of gravity have been studied extensively. In this work, we considered logarithmic correction to the trace term T and took the functional form as f(R, T) = R+16πGαlnT where α is a free parameter. The free parameter is constrained using dark energy density parameter ΩΛ and Hubble parameter H0. The lower bound is found to be α ≥ −9.85×10−29. The cosmological implications are also studied.
Cosmic Evolution in a Bianchi type-V Universe with Barrow Holographic Dark Energy with Granda-Oliveros Length Scale as IR Cutoff
Authors: Mahanta Rajashree , Mahanta Chandra Rekha , Medhi Joy Prakash
Published: November 2024

In this work, we construct a spatially homogeneous and anisotropic Bianchi type-V cosmological model with a hybrid expansion law by considering the universe to be filled with cold dark matter and non-interacting Barrow holographic dark energy with Granda-Oliveros length scale as IR cutoff. The physical and kinematical characteristics of the resulting model are discussed by studying the evolution of various parameters of cosmological importance such as the Hubble parameter, the deceleration parameter, the anisotropic parameter, the equation of state parameter, jerk parameter etc. We also examine whether the energy conditions are satisfied or violated. Our analysis reveals that the Null,Weak, and Dominant energy conditions are fullfilled, while the Strong Energy Condition is violated, which supports the accelerated expansion of the universe. Statefinder diagnostics have also been performed based on recent cosmological observations in order to compare our model with different dark energy cosmological scenario. Additionally, we establish the correspondence between the quintessence scalar field and the Barrow holographic dark energy model,  supporting our description of the universe’s accelerated expansion.
Spectral and Timing Study of V404 Cygni with CHANDRA Observations
Authors: Devi S. Rita , Devi A. Senorita , Deshamukhya Atri
Published: November 2024

We present the spectral and timing study of V404 Cygni from all its available Chandra observations and which recently come up in public domain of Chandra data archive. The data reduction and analysis were done using CIAO 4.14 and HEASOFT 6.30.1. The spectral analysis was done using spectral fitting package XSPEC version 12.12.1, available in the Heasoft package. The spectra of the source is fitted in the energy range 0.3 -8.0 keV using two empirical spectral models - the absorbed power law and an absorbed disk-blackbody. The X-ray binary source V404 Cygni is found to be in the quiescent state having the X-ray luminosity in the range withfew times 1032 erg s−1. The source is found to be in the hard state and is well explained by power-law model with a powerlaw photon index Γ ∼ 2 with nH in the range ∼ (0.7 -1.2) × 1022 cm−2. From timing analysis, Src-1 (V404 Cygni), in all the time bins- 0.5, 1 and 2 ks, the probability for the count rate to be constant is 0.17 ×10−33 in all the observations in the year 2021 and 2023 (ObsID 23421, ObsID 23422, ObsID 23423 & ObsID 28927). However, in the year 2017 observation it is found to be less variable. This clearly shows the presence of short-term variability in kilo-seconds time-scales with the currently available Chandra data. So, it is indicative that the binary source V404 Cygni is more likely to be variable source both in long-term (years) as well as short-term (kiloseconds) scales.
Method of Digital Processing of Optical Spectra of Magnetron Discharge Plasma
Authors: Afanasieva Inna , Afanasiev Serhii , Bobkov Valentin , Gritsyna Valentina , Skrypnyk Anatoliy
Published: November 2024

To solve the actual problems associated with the development of the theory of magnetron discharge and the expansion of its practical application, a digital method of recording and processing the discharge plasma luminescence spectra is proposed in this work. To obtain the discharge plasma glow spectra, a photographic technique was used, which allowed simultaneous recording of the entire radiation spectrum in the 390.0-700.0 nm region. An additional advantage of this technique is the ability to track spatial changes in the composition and properties of the plasma in the discharge in the selected direction. A Canon EOS 80D digital camera with remote control was used to record the optical signal. A graphical application OSA was created to process digital images of the discharge plasma luminescence spectra. The paper describes the functionality of this application: determination of the wavelength of a spectral line and its belonging to a certain chemical element; measurement of the spatial distribution of the intensity of a spectral line along the selected direction of radiation registration. Determining the wavelength of a spectral line in the application is possible in two modes of operation - automatic and manual. In the first mode, the algorithm developed in this paper determines the wavelength for all spectral lines whose intensity exceeds the background value at a height of 10 % of the lower spectral limit. The second mode allows you to independently select a single spectral line or several to determine their wavelengths. The first mode is used for quick analysis, while the second mode allows you to determine the length of the spectral line with greater accuracy. To interpret the spectral lines, the methodology of reference lines from the databases of spectral line tables for various elements is used. The possibility of both full automatic verification, where all elements are sequentially searched, and selective verification, where one or more elements are selected, is provided. The paper shows that the spatial distribution of the intensity of tungsten spectral lines, and thus of excited atoms in a magnetron discharge, is a complex function of the distance from the cathode, which depends on the discharge parameters. The proposed digital methodology makes it possible to significantly speed up the process of obtaining physical information and increase the accuracy in determining the spectrum parameters.
Entropy Generation Analysis on Hybrid Dusty Nanofluid Flow Over a Heated Stretching Sheet: Aerospace Technology
Authors: Ramasekhar Gunisetty , Selvi P.D. , Reddy Madduru Sudhakara , Reddy S.R.R. , Jakeer Shaik , Suneetha Sangapatnam
Published: November 2024

The past few years have seen enormous investments in research and development of next generation technologies with potential use in aerospace. Engine oil provides grease, air conditioning, maintenance, rust prevention, reduced sound and turbine functioning among its many functions within an airplane engine. Among these, lubrication is paramount. Without lubrication, it goes without saying that any moving components would wear out very fast. The present study investigates the significance of heat transport properties entropy generation on MHD dusty hybrid nanofluid flow over a heated stretching sheet in the presence of heat generation. By using the suitable self-similarity variables, the partial differential equation is transformed into ordinary differential equations. After then, the dimensionless equations are solved by using the MATLAB solver in bvp4c scheme. Graphs and tables are explained how the operational factors affect fluid flow efficiency. The velocity profile enhanced for increasing magnetic field values, however the energy outline exhibited the reverse behavior, which we observed. During the course of our research, we came to the conclusion that mixed nanofluids are superior to dusty small fluids in terms of their ability to transport energy transporters.
Flow of Magnetohydrodynamic Maxwell Fluid in Darcy – Forchheimer Model, With Cattaneo – Christov Heat Flux, Over A Stretching Sheet Subjected to Convective Boundary Conditions
Authors: Babu D. Dastagiri , Venkateswarlu S. , Naik R. Hanuma , Manjula D.
Published: November 2024

This research communication explores the Darcy - Forchheimer flow of a chemically reacting non-Newtonian Maxwell fluid over a stretching sheet, incorporating the Cattaneo – Christov heat flux under a convective boundary condition. The fluid flow is described by a set of partial differential equations, which are subsequently transformed into a system of nonlinear ordinary differential equations. To solve these equations numerically, the BVP4C Method was employed after appropriately defining non dimensional variables and implementing similarity transformations. The impacts of diverse active parameters such as Deborah parameter, Darcy‑Forchheimer parameter, magnetic parameter, Biot number, and porous parameter are examined on the velocity, temperature, and concentration profiles. In addition, the value of the Skin friction, Nusselt number is calculated and presented through tabular forms.
Influence of Heat and Mass Transmission on the MHD Fluid Circulation in Conjunction with an Upright Surface in the Emergence of Radiation Thermophoresis and the Dufour Repercussions
Authors: Mirza Ashik Hussain , Dey Bamdeb , Choudhury Rita
Published: November 2024

The current research simulates the mass and heat energy transmission model on MHD fluid flow under concentration and temperature deviations on a two-dimensional viscous fluid along an upright facet. Following boundary layer estimations, mathematical simulations for the movement of fluids, the conveyance of heat and mass exposed to radiation, thermophoresis, and Dufour consequences are generated as a set of partial differential equations. The surface's resilient suction was assessed. The built-in solver bvp4c in MATLAB is used for numerically debugging the aforementioned models. Through the inclusion of visualizations and tables, the detrimental effects of influencing variables are examined on the velocity, temperature as well as concentration gradients in conjunction with on the skin friction, Nusselt number, and Sherwood number. Excellent coherence may be shown when comparing between the most present findings and those that have previously been made available in the literature in specific limited circumstances. The Dufour effect, radiation, thermophoresis, and the Grashof number are all factors that influence fluid motion and heat transmission at the interface layer of dirt. Moreover, developments in the Shearing stress, Nusselt number, and Sherwood number coefficient are calculated. The findings are crucial for optimizing a variety of fluid-based technologies and systems, allowing developments in a number of industries including energy-effectiveness, electronics cooling, pursued medicine administration, and many more.
Structural Properties of Al-Doped ZnO Films
Authors: Zainabidinov Sirajidin S. , Yulchiev Shakhriyor Kh. , Boboev Akramjon Y. , Gulomov Bakhtiyor D. , Yunusaliyev Nuritdin Y.
Published: November 2024

In this study, the results of the investigation of the influence of Al atoms on the structural characteristics of ZnO films obtained by the sol-gel method are presented. It has been determined that the glass substrates consist of subcrystallites with dimensions of 28.6 nm, having cubic unit cells with lattice parameters a = 0.3336 nm, and their surfaces belong to the crystallographic orientation (111). It has been identified that the grown thin ZnO films consist of subcrystallites with dimensions of 39.5 nm, having a wurtzite structure with lattice parameters a = b = 0.3265 nm and c = 0.5212 nm, respectively. It has been determined that at the boundaries of the division of these subcrystallites, polycrystalline regions with sizes of 12.6 nm, 28.3 nm, 30 nm, and 33 nm are formed. Additionally, nanocrystallites with sizes of 56.8 nm self-assemble on the surface areas of the deposited films. The increase in the values of the “c”axis of the hexagonal crystal lattice of ZnO films by 0.0009 nm when doping Al atoms from 1% to 5% is explained by the shift of the main structural line (002) at small angles (Δθ=0.12°). It has been established that nanocrystallites with lattice parameters аn = 0.5791 nm, belonging to the spatial group Fd3m, self-assemble on the surface areas of ZnO:Al films. the curve due to the presence of a monoenergetic level of fast surface states at the heterojunction.
Analysis of the Influence of Formation of Pd Silicides on Surface Layers of Si on the Diffusion of Atoms of Contacting Metal
Authors: Tashmukhamedova D.А. , Abdiev X.E. , Gulyamova S.T. , Rabbimov E.A. , Umirzakov B.E.
Published: November 2024

4-probe measurements of surface resistivity, measurements of dark and light current-voltage characteristics, the possibilities of using a thin PdSi film to obtain perfect nano-sized ohmic contacts on the Si(111) surface have been investigated using Auger electron spectroscopy methods in combination with ion etching of the surface. It has been shown that the depth of Ni diffusion in the Ni-Si (111) system is 400 ‑ 500 Å at indoor temperature, and 70 – 80 Å in the Ni-PdSi-Si (111) system. The quality of the ohmic contact in the latter case does not change up to T = 800 K and withstands luminous flux illumination up to F = 1100 lux. It is shown that the resistivity of the PdSi film passes through a minimum at T = 900 – 1000 K. An analysis of the results obtained will be given in the article.
Computational Investigation on the Structural, Electronic and Magnetic Properties of Si-Doped L10 FeNi Alloy for Clean Energy
Authors: Zine Zineb , Meftah Nassima
Published: November 2024

For the first time, this study conducts a computational analysis by employing density functional theory (DFT) to investigate the effects of silicon doping as substitutional defects on the structural, electronic, and magnetic characteristics of the L10-FeNi alloy. The aim of this study was to explore the potential applications of Si-doped FeNi compounds as alternatives to rare-earth permanent magnets. For this, we have performed full potential calculations of L10-FeNi with substitutional Si-doping within a generalized gradient approximation. Two types of substitutional Si-doping (ONi/OFe) in the Ni/Fe site of the parent alloy have been investigated. The computed formation energy (Ef) indicates that the incorporation of silicon defects increases the structural stability of tetragonally distorted L10-FeNi. Moreover, our findings demonstrate that the FeNi:Si(ONi) in the L10-structure has a stable saturation magnetization (Ms), whereas the FeNi:Si (OFe) has a small reduction in Ms. Therefore, Si-substituted FeNi alloys can be tuned to become a good candidate for permanents magnets.
Development of a Capacitive Pressure Sensor Based on Nanoporous Anodic Aluminium Oxide
Authors: Das Trishna Moni , Sarmah Devabrata , Borah Sankar Moni , Baruah Sunandan
Published: November 2024

Capacitive pressure sensors make pressure sensing technology more accessible to a wider range of applications and industries, including consumer electronics, automotive, healthcare etc. However, developing a capacitive pressure sensor with brilliant performance using a lowcost technique remains a difficulty. In this work, the development of a capacitive pressure sensor based on nanoporous AAO fabricated by a two-step anodization approach which offers a promising solution for precise pressure measurement is fabricated by a two-step anodization approach. A parallel plate capacitive sensor was fabricated by placing two AAO deposited sheets are placed face to face, with the non-anodized aluminum component at the base functioning as the top and bottom electrodes. A variation in the capacitance value of the as fabricated sensor was observed over an applied pressure range (100 Pa-100 kPa). This change in capacitance can be attributed to the decrease in the distance between the two plates and the non-homogenous distribution of contact stress and strain due to the presence of nanoporous AAO structure. In this pressure range the sensor showed high sensitivity, short response time and excellent repeatability which indicates a promising future of the fabricated sensor in consumer electronics, intelligent robotics etc.
Numerical Simulation Study of The Increase in Electrical Efficiency of the CIGS-Based Solar Cell by SCAPS-1D
Authors: Madoui K. , Ghechi A. , Madoui S. , Yekhlef R. , Belfennache D. , Zaiou S. , Ali Mohamed A.
Published: November 2024

Solar cells are currently the focus of a great deal of research. The aim is to reduce their cost price. To achieve this, we need to reduce the mass of the materials and increase the conversion efficiency of these solar cells. This has motivated research into the use of thin films such as a-Si, CdTe, CIGS. This increase in efficiency requires optimizing the performance of the photovoltaic parameters. In this modeling and simulation work, we use the SCAPS-1D software to study the effect of the recombination speed of the electrons and holes in the CIGS layer, the effect of the thickness of the layers and the effect of the gap energy of each layer of the material used for this solar cell on the short-circuit current Jsc, the open-circuit voltage Voc, the form factor FF and the electrical efficiency η of the CIGS cell for a Mo/p-CIGS/p-Si/In2S3/i-ZnO/Al-ZnO single-junction structure. In this study, we found that recombination speed affects the efficiency of the photovoltaic cell. The gap energy of the absorber layers influences the cell's efficiency, while the other layers (In2S3, ZnO, Al-ZnO) do not have a great influence on solar cell performance and increasing the thickness of the absorber layer has a major influence on efficiency, increasing it up to a certain limit. The thicknesses of the CIGS, p-Si, In2S3, i-ZnO and Al‑ZnO layers need to be in the order of 0.3µm, 0.8µm, 0.05µm, 0.07µm and 0.1µm respectively to achieve better efficiency (31.42%).
SCAPS-1D Analysis of Non-Toxic Lead-Free MASnI3 Perovskite-Based Solar Cell Using Inorganic Charge Transport Layers
Authors: Amanyi Matthew I. , Yusuf Abubakar S. , Akpoguma Eghwubare , Eghaghe Stephen O. , Eneye James , Agaku Raymond M. , Echebiri Lilian C. , Echebiri Emmanuel U. , Ameh Emmanuel O. , Eririogu Chinyere I. , Tasie Nicholas N. , Ozurumba Anthony C. , Danladi Eli
Published: November 2024

Perovskite solar cells (PSCs) have gained a lot of attention due to their high efficiency and low cost. In this research paper, a methylammonium tin iodide (CH3NH3SnI3) based solar cell was simulated using a one-dimensional solar cell capacitance simulation (SCAPS-1D) tool. The SCAPS-1D tool is based on Poisson and the semiconductor equations. After thorough investigation, the initial device presents the following parameters; power conversion efficiency (PCE)=15.315%, fill factor (FF)=64.580%, current density (Jsc)=29.152 mA/cm2, and open circuit voltage (Voc)=0.813 V. The effect of absorber and ETL thicknesses were explored systematically. The performance of the simulated device was significantly influenced by the thickness of the absorber and ETL. The optimized absorber thickness was 0.5 µm and the ETL thickness was 0.02 µm, giving rise to an optimized PCE of 15.411%, FF of 63.525%, Jsc of 29.812 mA/cm2, and Voc of 0.814 V. Additionally, the effect of temperature on the optimized device was evaluated and found that it affects the performance of the device. This model shows the prospect of CH3NH3SnI3 as a perovskite material to produce toxic-free environment-friendly solar cells with high efficiency.
Protective Effect of Quercetin on Amyloid-Induced Alterations in Lipid Bilayer Integrity
Authors: Tarabara Uliana , Trusova Valeriya , Gorbenko Galyna
Published: November 2024

The present study employs molecular dynamics simulations to investigate the interactions between quercetin, amyloid fibrils, and POPC lipid bilayers. The results demonstrate that quercetin does not significantly affect the molecular organization of the bilayer, while IAPP fibrils induce substantial structural changes, particularly in the outer monolayer. Quercetin mitigates these effects by reducing the impact on headgroup and glycerol regions and causing a more superficial positioning of IAPP. Additionally, quercetin slightly decreases the order of sn-2 acyl chains, indicating a disordering effect. In a ternary system with POPC, quercetin, and IAPP, the reduction in the deuterium order parameter of sn-2 acyl chains is less pronounced, underscoring quercetin's protective role. Unlike IAPP, ApoAI and insulin fibrils undergo significant structural reorganization in the membrane-bound state. Quercetin attenuative effects are observed only with ApoAI, highlighting its potential as a protective agent against amyloid-induced membrane disruption. These findings provide valuable insights into the interactions between polyphenols, amyloid fibrils, and lipid membranes, contributing to the understanding of membrane-associated amyloid pathologies.
Molecular Docking Study Of Protein-Functionalized Carbon Nanomaterials For Heavy Metal Detection And Removal
Authors: Zhytniakivska Olga , Tarabara Uliana , Vus Kateryna , Trusova Valeriya , Gorbenko Galyna
Published: November 2024

Carbon nanomaterials (CNMs) have emerged as highly effective agents for the removal of heavy metals from contaminated water and environments, owing to their unique structural and chemical properties. However, the hydrophobic nature of CNMs and their tendency to aggregate in most solvents present significant challenges to their practical application. Functionalizing carbon-based nanomaterials with proteins offers a promising solution to these issues, potentially leading to systems with unprecedented performance. Before fabricating protein-CNM systems for heavy metal detection and removal, it is crucial to evaluate the metal-binding affinity and potential interaction modes using computational approaches. In this study, a molecular docking technique was employed to investigate the interactions among heavy metal salts (AsO₄, Cd(NO₃)₂, Fe(NO₃)₃, NiSO₄, PbSO₄, PtCl₄), carbon-based nanomaterials (fullerenes C₂₄ and C₆₀, and single-walled carbon nanotubes), and β-lactoglobulin. The docking results revealed that: 1) the size, shape, and surface properties of carbon-based materials significantly influence the ability of β-lactoglobulin-CNM complexes to interact with different heavy metals; 2) different heavy metal salts exhibit distinct preferences for the various nanosystems; 3) hydrogen bonding and hydrophobic interactions play a significant role in the complexation of heavy metal salts with β-lactoglobulin-carbon-based materials.
Using the parameters of the series lengths as an element of the interblock data multiplex of the steganoalgorithm.
Authors: Honcharov Mykyta , Liesnaia Yuliia
Published: November 2024

Рассмотрены особенности использования параметров длин серий и количества сформированных опорных блоков, как элементов составного ключа экстрактора данных, гибридного стеганоалгоритма. Представлены результаты атаки (взлома) тестовых изображений, полученные для стеков выборки разной длины (разной базы перестановок действующих параметров серий). Сделан вывод о ведущей роли параметра «длин серий» при реализации процедур межблочного мультиплексирования стеганоконтента. Подчеркнуто, что одновременное использование 2-х уровневого мультиплекса данных значительно расширяет возможности противостояния попыткам атак контента. Установлено, что применение блоков с большей размерностью, существенно уменьшает роль параметра «длин серий», как основного элемента разрушения структуры исходных изображений. Констатируется, что увеличение длины стека выборки серий, расширяет потенциальную комбинаторику мультиплексирования действующих пар параметров серий, и в большей степени разрушает корреляционные связи элементов исходного массива данных. По результатам моделирования сделан вывод, что внедрение различных способов развертки серий обеспечивает еще одну позицию в структуре ключа экстрактора данных.
Analysis of data search methods in cryptographically protected databases.
Authors: Makhmudov Teimur , Yesin Vitalii
Published: November 2024

The issue of compliance with data security, namely their confidentiality and integrity, generally being resolved through the use of appropriate cryptographic primitives, taking into account the development of computing power (and/or computational complexity of algorithms). But, in connection with the specific method of storage (in the cloud), the question arises of the effectiveness of the search for the necessary information. The problem considered in this paper is that encryption makes it impossible for an attacker to access data without access key, but deprives the legal owner of the data, of the ability to search for this information.  The article reviewe several encryption methods with searchable. For each of them algorithms given, examples of the use of these methods, explanatory figures and tables were provided. The considered methods are symmetric and dynamic, due to which they are effective and have a relatively high level of security, but low query expressiveness, which is why they are most used in NoSQL data-bases. The analysis was conducted to evaluate the complexity and level of security of the methods, and the performance of practical implementations was also considered. It was concluded that, conclusions were made about the feasibility of using one or another searchable encryption method in practice, and recommendations were made regarding the combination of the described methods to obtain expected results.
The analysis of development, typical objectives and mechanisms of phishing attacks
Authors: Liesnaia Yuliia , Malakhov Serhii
Published: November 2024

The work discusses the issues of phishing attacks, emphasizing the interconnection between the stages of information technology development and the periods of phishing evolution. Attention is drawn to the fact that any new communication resource or online technology significantly expands the range of possible social engineering techniques, a key element of modern phishing. Based on a review of known incidents, it is asserted that this type of attack will continue to proliferate. The main factors contributing to the further growth of phishing include: -active implementation of artificial intelligence and Internet of Things technologies; -proliferation of satellite Internet; -persistent increase in the number of network users; -technological rivalry among major actors in the post-industrial world. It is emphasized that the increased accessibility of the global Internet will lead to a rise in the number of users of new communication services and platforms. However, the widespread digitization of modern society, coupled with low levels of digital literacy in certain social strata, will result in potential vulnerabilities for large groups of technologically uninformed users. The simultaneous existence of these two trends will increase the number of potential phishing attack victims in the future. It is highlighted that integrating phishing with other types of cyberattacks increases the overall incidence of phishing. The significant prevalence of social networks is noted as a major means of phishing dissemination. The conclusion is drawn that phishing attacks in corporate and private segments of modern information systems, despite their external similarities, aim to obtain substantially different "bonuses" in terms of scale, consequences, and substantive actions. These implicit differences determine the variations in impact vectors and attacking scenarios. Special attention is given to the use of multi-factor authentication, which significantly complicates the impersonation of user identification data, making phishing less effective. It is noted that implementing comprehensive protection against phishing attacks involves continuous improvement of existing security technologies in conjunction with organizational measures. The organizational component should clearly regulate the levels of personal and collective responsibility for the current security status of the utilized systems and information resources.
A short survey of the capabilities of Next Generation firewalls
Authors: Sichkar Mykhailo , Pavlova Larysa
Published: November 2024

This article examines the history, types, capabilities, and advantages of next-generation firewall (NGFW) technology. Firewalls are an important tool for protecting network resources from various information security threats. With the development of technology and the changing nature of attacks, especially those involving artificial intelligence, firewalls have also evolved, acquiring new functions and capabilities. This work provides a short survey of the main types, capabilities and benefits of next-generation firewall (NGFW) technology, which is a modern solution for comprehensive network protection against complex and sophisticated security threats. The work also analyzes the distinct features of NGFW and differences between NGFW and previous generations of firewalls, as well as examples of NGFW from well-known vendors that dominate the market, such as Palo Alto Networks, Fortinet and Cisco. The article highlights the main trends, prospects for the development and implementation of NGFW, including the impact of artificial intelligence, machine learning, cloud technologies and the Internet of Things, advantages and disadvantages, capabilities, important aspects, purpose and sphere of application. The article also addresses the significant impact this technology will have on network security. It is emphasized that the introduction of NGFW does not replace other security technologies and tools, but effectively expands the existing arsenal of countering new security threats (primarily as an instrument of proactive countermeasures and rapid response to complex network incidents). The article may be useful for students, researchers, and information security professionals who seek to expand their competencies related to the development of modern firewall technologies and their capabilities.
Features of software implementing the prefix search method in cryptographically protected databases
Authors: Lilikovych Serhii , Yesin Vitalii
Published: November 2024

The article addresses the specific considerations associated with the development of software implementing the prefix search method in cryptographically protected databases. This method is a variant of symmetric searchable encryption, which allows search among the encrypted data. The prefix search method allows searching for prefixes among encrypted data without the need for decryption. Such an approach resolves the issue of maintaining data confidentiality stored on remote or cloud servers. However, its usage introduces a set of issues that must be considered during the development of the corresponding software. The paper analyzes the requirements for software that implements the prefix search method, defines the software architecture, and justifies the choice of technologies and tools for software implementation, including ASP.NET, Java, JavaScript, PHP, Python programming languages, MongoDB database management system, and the FastAPI framework. A description of the deployment process of the corresponding software is provided. To assess the performance of the developed software, the well-known Apache JMeter tool for conducting load testing was utilized. The obtained performance evaluations of the proposed solution indicate acceptable time delays in processing relevant data search queries.
Analysis of cybersecurity features in banking mobile applications
Authors: Lohachova Yelyzaveta , Yesina Maryna , Bobukh Vsevolod
Published: November 2024

This article discusses important aspects of cybersecurity in mobile banking applications. The article analyses in detail potential threats and effective strategies for their prevention and counteraction. Due to the rapid development of digital technologies in the banking industry, mobile applications and online services have become a necessary component of financial interaction between customers, providing convenient and efficient financial transactions. However, the development of the functionality of such applications gives rise to new cybersecurity challenges that information security professionals are actively addressing. The article is devoted to a comprehensive review of international and Ukrainian cybersecurity standards in the banking sector, and also contains quick review of mobile applications of well-known Ukrainian banks. Based on this review basic recommendations for improving cybersecurity in such applications are formulated. The article considers the impact of customer comfort on the level of security. In addition, the article considers the impact of the level of security in the banking sector on the overall digitalisation of the financial industry. It is noted that improving the level of security can stimulate and support digitalisation processes, ensuring customer trust and optimal use of mobile banking applications. A comprehensive approach to assessing the level of security, comparing various applications and standards (both Ukrainian and international), as well as considering the relationship between security issues and innovations in banking, make this work useful for understanding the genesis of cyber security in mobile banking.
Results of modeling different schemes of the spatial orientation and scanning series of base blocks of images to confront an unauthorized extraction of steganographic data
Authors: Honcharov Mykyta , Malakhov Serhii , Kolovanova Ievgeniia
Published: November 2024

This work presents the results of modeling attempts at unauthorized extraction of steganocontent (halftone test images) under the condition of selective compromise of each of the two active processing parameters of the source array series of base blocks (BB) of content, i.e.: - the scheme scanning of BB series and the spatial processing of BB. The current program version ensures consistent realization of the main stages of content processing with the necessary settings parameters. As part of the modeling, it is suggested that the attacker has correctly identified one of the two current content processing parameters. Several modifications of the main schemes scanning of BB series and the spatial orientation of BB (rotation and horizontal mirroring) as an additional mechanism to counteract attempts of illegitimate content extraction are considered. The modeling was conducted on the examples of three types of images: - portrait, landscape, and mnemonic scheme. Manipulations with the spatial orientation parameter of BB strengthen the opportunities to counteract attempts at unauthorized data extraction. Characteristic quantitative and time histograms for different dimensions BB of content, changes in the peak of value signal-to-noise ratio for different types of schemes scanning BB series are presented, and samples of attacked test images are presented. The analysis and generalization of the main differences in the attack results using different parameters of the spatial processing of BB and ways of scanning series of BB of image-content are performed. Attention is drawn to the fact that the use of two active processing parameters of the source array of BB series is an effective and computationally «simple» means of counteracting attempts at unauthorized data extraction. The relationship between the stage of preprocessing the source content and the parameters of the formed arrays BB is emphasized. It is concluded that the introduction into the structure of the data extractor key, the elements of «The state of scanning» and «The spatial processing of BB», strengthens the overall capabilities to counteract attacks. The used processing parameters of the source array of BB series determine the structure of visual artifacts of attacked images but do not produce a simple solution to identify the attacked image at the level of classifying the type of source images. Prospective directions for further modeling of the main protection mechanisms within the proposed algorithm concept are indicated.
Business development management tools in the digital economy
Authors: Samorodov Borys , Kotkovskyi Volodymyr , Malafieiev Timur
Published: November 2024

The peculiarities of the digital environment, which contribute to the rapid growth of instability in enterprises' activities, are highlighted. The need to refine certain aspects and tools of traditional strategic planning is substantiated. The essence of digital transformation as a strategic process of business change—based on client-centric principles, systemic innovation, business model adaptation, active data usage, and competency development—is defined. The problems facing Ukrainian companies in digital transformation are highlighted, including insufficient strategy development, organizational culture misalignment with necessary changes, a shortage of digital skills, outdated technologies, lack of coordination between old and new technologies, and the high costs of implementing innovations. The approach to the digital transformation strategy is viewed as a tool for setting priorities that provides businesses with competitive advantages in rapidly changing markets through the application of digital technologies to solve new business challenges. Potential directions for ensuring the flexibility of a digital strategy are highlighted, such as developing partnerships and cooperation, utilizing big data analysis and predictive analytics for real-time decision-making, and employing flexible technologies for both implementation and strategy development. A hypothesis about the feasibility of developing a minimally viable strategy is proposed. As an additional method for increasing the flexibility of the digital transformation strategy, a modular structure for its design is proposed, based on the concept of business architecture, establishing a close connection between enterprise strategy, business model, and IT architecture. A brief overview of digital business models is provided, indicating that ecosystem-type business models, including digital platforms, are the most successful in the digital environment. The stages of digital transformation are outlined, and additional tools for their implementation are considered, such as digital maturity assessment models, a system of key indicators, and a digital transformation road map. A generalized structure of the toolkit for strategic management of business development in the digital environment is proposed, particularly aligned with the stages of digital transformation implementation.
Development of methods for assessing the digital maturity of business
Authors: Denchyk Iryna
Published: November 2024

The process of digital transformation is evident across all sectors of the Ukrainian economy. This underscores the importance of assessing the digital maturity of enterprises, particularly given regional differences, which has become a pressing issue during the full-scale invasion. The purpose of this study is to create an economic tool for assessing the digital maturity of organizations, taking into account the regional context. To achieve this goal, the following tasks were addressed: an analysis of theoretical approaches to the assessment of digital maturity was conducted, a system of indicators reflecting regional characteristics was identified, and an algorithm was developed to assess the digital maturity of organizations and interpret the results.
The article proposes an economic tool for assessing the digital maturity of organizations that considers both internal and external factors using quantitative indicators. Internal digital maturity is assessed according to two groups of factors: scientific and technical, and production, while external digital maturity considers four regional aspects: human resources, financial resources, consumer demand, and infrastructure. Methods of data normalization are used for comparison, and the analytic hierarchy process (AHP) is applied to account for the importance of each factor. The assessment of digital maturity enables the identification of the development level, as well as weaknesses that require attention to enhance digital transformation. The results can be utilized to develop strategies for managing the digital transformation of enterprises and shaping regional policies.