bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Woven Glass-Fibre Prepreg Orientation on the Flexural Properties of a Sustainable Composite Honeycomb Sandwich Panel for Structural Applications
Authors: Amir Abd Latif , Ishak Mohammad Ridzwan , Yidris Noorfaizal , Zuhri Mohamed Yusoff Mohd , Asyraf Muhammad Rizal Muhammad , Zakaria Sharifah Zarina Syed
Published: July 2023

Owing to the high potential application need in the aerospace and structural industry for honeycomb sandwich composite, the study on the flexural behaviour of sandwich composite structure has attracted attention in recent decades. The excellent bending behaviour of sandwich composite structures is based on their facesheet (FS) and core materials. This research studied the effect of woven glass-fibre prepreg orientation on the honeycomb sandwich panel. A three-point bending flexural test was done as per ASTM C393 standard by applying a 5 kN load on different orientation angles of woven glass-fibre prepreg honeycomb sandwich panel: α = 0°, 45° and 90°. The results show that most of the sandwich panel has almost the same failure mode during the three-point bending test. Additionally, the α = 0° orientation angle shows a higher maximum load prior to the first failure occurrence compared to others due to higher flexibility but lower stiffness. In addition, the woven glass-fibre prepreg orientation angle, α = 0°, has the maximum stress and flexural modulus, which directly depend upon the maximum load value obtained during the flexural test. In addition, the experimental results and analytical prediction for honeycomb sandwich deflection show good agreement. According to the result obtained, it is revealed that woven glass-fibre honeycomb sandwich panels with an α = 0° orientation is a good alternative compared to 45° and 90°, especially when better bending application is the main purpose. The final result of this research can be applied to enhance the properties of glass-fibre-reinforced polymer composite (GFRPC) cross-arm and enhance the existing cross-arm used in high transmission towers.
Experimental Validation of Dynamic Response of Small-Scale Metaconcrete Beams at Resonance Vibration
Authors: Ansari Meisam , Tartaglione Fabiola , Koenke Carsten
Published: July 2023

Structures and their components experience substantially large vibration amplitudes at resonance, which can cause their failure. The scope of this study is the utilization of silicone-coated steel balls in concrete as damping aggregates to suppress the resonance vibration. The heavy steel cores oscillate with a frequency close to the resonance frequency of the structure. Due to the phase difference between the vibrations of the cores and the structure, the cores counteract the vibration of the structure. The core-coating inclusions are randomly distributed in concrete similar to standard aggregates. This mixture is referred to as metaconcrete. The main goal of this work is to validate the ability of the inclusions to suppress mechanical vibration through laboratory experiments. For this purpose, two small-scale metaconcrete beams were cast and tested. In a free vibration test, the metaconcrete beams exhibited a larger damping ratio compared to a similar beam cast from conventional concrete. The vibration amplitudes of the metaconcrete beams at resonance were measured with a frequency sweep test. In comparison with the conventional concrete beam, both metaconcrete beams demonstrated smaller vibration amplitudes. Both experiments verified an improvement in the dynamic response of the metaconcrete beams at resonance vibration.
Porous Rod-like NiTiO3-BiOBr Heterojunctions with Highly Improved Visible-Light Photocatalytic Performance
Authors: Sun Kaiyue , Li Mengchao , Zhou Hualei , Ma Xiaohui , Li Wenjun
Published: July 2023

NiTiO3-BiOBr heterostructured photocatalysts were constructed via precipitation, calcination and hydrothermal treatments. Various characterizations demonstrated that BiOBr nanosheets were decorated on NiTiO3 nanoparticals, forming porous rod-like heterojunctions. Compared with independent NiTiO3 and BiOBr, the composites with optimal BiOBr content presented highly improved visible-light photocatalytic efficiency. The degradation rates of Rhodamine B (RhB) and tetracycline (TC) reached 96.6% in 1.5 h (100% in 2 h) and 73.5% in 3 h, which are 6.61 and 1.53 times those of NiTiO3, respectively. The result is an improved photocatalytic behavior from the formation of heterojunctions with a large interface area, which significantly promoted the separation of photogenerated carriers and strengthened the visible-light absorption. Based on the free radical capture experiments and band position analysis, the photodegradation mechanism of type-II heterojunction was deduced. This study provides a new way to fabricate highly efficient NiTiO3-based photocatalysts for degrading certain organics.
Performance Optimization of Ultralow-Frequency Electromagnetic Energy Harvester Driven by Eccentric mass
Authors: Liang Jintao , Zhang Chao , Fan Kangqi
Published: July 2023

Driven by an eccentric mass through a two-layered cantilevered plectrum, the electromagnetic energy harvester (EEH) can convert low-frequency mechanical vibrations into continuous uni-directional rotation. To optimize the performance of the EEH, electromagnetic analysis of the EEH was conducted. Three-phase winding permanent magnet (PM) topology was employed, and combinations of different coils and magnet pole numbers were designed. Then, the finite element method (FEM) was applied to analyze the influence of the combinations of the coils and pole numbers as well as the PM dimensions on the three-phase induced voltage. Prototypes with different configurations were fabricated and the analysis effectiveness was confirmed. Furthermore, different types of stator yokes were designed to enhance the magnetic field. Compared to the original prototype, the output voltage of the optimal prototype increased by 0.5 V with the same rotation speed, and the harmonic components were sufficiently low. Then, experiments with excitation by linear reciprocating motions and swing motions were conducted. Under different exciting conditions, the optimal prototype can also induce the highest voltage amplitude. With an increase in the weight of the eccentric mass, a long duration can be reached that lasts up to 12 s. In summary, the proposed optimization can achieve a high-efficiency and high-power density EEH.
Stator Inter-Turn Short-Circuits Fault Diagnostics in Three-Phase Line-Start Permanent Magnet Synchronous Motors Fed by Unbalanced Voltages
Authors: Fonseca D. S. B. , Antunes Hugo R. P. , Cardoso Antonio J. Marques
Published: July 2023

This paper addresses the diagnostics of stator faults in three-phase line-start permanent magnet synchronous motors. More traditional fault diagnostic methodologies are unable to properly diagnose stator inter-turn short-circuit faults in three-phase motors under unbalanced supply voltage conditions, since both conditions impact the fault indicators used for inter-turn short-circuit fault diagnostics in a similar way. In this paper, the relation between the symmetrical components of the three-phase quantities and the harmonic components of the Extended Park’s Vector Approach (EPVA) is established. It is proved that the negative component and the EPVA harmonic component at a frequency twice the supply frequency are directly related to the fault occurrence. It is also proved that the healthy motor negative impedance is constant and not load-dependent. Based on this, the negative impedance/admittance is indirectly analyzed, through the combined use of the Extended Park´s Vector Approach of both voltage and current, and is explored for the fault diagnostics. Experimental results, obtained for different load torques, unbalanced supply voltage values, and fault severity levels, show that inter-turn short-circuit fault diagnostics can be achieved even under unbalanced supply voltage conditions based on the analysis of the motor admittance, at a frequency twice the supply frequency, that is the negative sequence admittance.
Electrically Detected Magnetic Resonance on a Chip (EDMRoC) for Analysis of Thin-Film Silicon Photovoltaics
Authors: Segantini Michele , Marcozzi Gianluca , Djekic Denis , Chu Anh , Amkreutz Daniel , Trinh Cham Thi , Neubert Sebastian , Stannowski Bernd , Jacob Kerstin , Rudolph Ivo , McPeak Joseph E. , Anders Jens , Naydenov Boris , Lips Klaus
Published: July 2023

Electrically detected magnetic resonance (EDMR) is a spectroscopic technique that provides information about the physical properties of materials through the detection of variations in conductivity induced by spin-dependent processes. EDMR has been widely applied to investigate thin-film semiconductor materials in which the presence of defects can induce the current limiting processes. Conventional EDMR measurements are performed on samples with a special geometry that allows the use of a typical electron paramagnetic resonance (EPR) resonator. For such measurements, it is of utmost importance that the geometry of the sample under assessment does not influence the results of the experiment. Here, we present a single-board EPR spectrometer using a chip-integrated, voltage-controlled oscillator (VCO) array as a planar microwave source, whose geometry optimally matches that of a standard EDMR sample, and which greatly facilitates electrical interfacing to the device under assessment. The probehead combined an ultrasensitive transimpedance amplifier (TIA) with a twelve-coil array, VCO-based, single-board EPR spectrometer to permit EDMR-on-a-Chip (EDMRoC) investigations. EDMRoC measurements were performed at room temperature on a thin-film hydrogenated amorphous silicon (a-Si:H) pin solar cell under dark and forward bias conditions, and the recombination current driven by the a-Si:H dangling bonds (db) was detected. These experiments serve as a proof of concept for a new generation of small and versatile spectrometers that allow in situ and operando EDMR experiments.
Survival Analysis of the PRC Model from Adaptive Progressively Hybrid Type-II Censoring and Its Engineering Applications
Authors: Elshahhat Ahmed , Abo-Kasem Osama E. , Mohammed Heba S.
Published: July 2023

A new two-parameter statistical model, obtained by compounding the generalized-exponential and exponential distributions, called the PRC lifetime model, is explored in this paper. This model can be easily linked to other well-known six-lifetime models; namely the exponential, log-logistic, Burr, Pareto and generalized Pareto models. Adaptive progressively hybrid Type-II censored strategy, used to increase the efficiency of statistical inferential results and save the total duration of a test, has become widely used in various sectors such as medicine, biology, engineering, etc. Via maximum likelihood and Bayes inferential methodologies, given the presence of such censored data, the challenge of estimating the unknown parameters and some reliability time features, such as reliability and failure rate functions, of the PRC model is examined. The Markov-Chain Monte Carlo sampler, when the model parameters are assumed to have independent gamma density priors, is utilized to produce the Bayes’ infer under the symmetric (squared-error) loss of all unknown subjects. Asymptotic confidence intervals as well as the highest posterior density intervals of the unknown parameters and the unknown reliability indices are also created. An extensive Monte Carlo simulation is implemented to investigate the accuracy of the acquired point and interval estimators. Four various optimality criteria, to select the best progressive censored design, are used. To demonstrate the applicability and feasibility of the proposed model in a real-world scenario, two data sets from the engineering sector; one based on industrial devices and the other on aircraft windshield, are analyzed. Numerical evaluations showed that the PRC model furnishes a superior fit compared to seven other models in the literature, including: alpha-power exponential, log-logistic, Nadarajah–Haghighi, generalized-exponential, Weibull, gamma and exponential lifetime distributions. The findings demonstrate that, in order to obtain the necessary estimators, the Bayes’ paradigm via Metropolis–Hastings sampler is recommended compared to its competitive likelihood approach.
Two-Grid Method for a Fully Discrete Mixed Finite Element Solution of the Time-Dependent Schrödinger Equation
Authors: Tian Zhikun , Chen Yanping , Wang Jianyun
Published: July 2023

We study the backward Euler fully discrete mixed finite element method for the time-dependent Schrödinger equation; the error result of the mixed finite element solution is obtained in the L2-norm with order O(τ+hk+1). Then, a two-grid method is presented with a backward Euler fully discrete scheme. Using this method, we solve the original problem on a much coarser grid and solve elliptic equations on a fine grid. In addition, the error of the two-grid solution is also obtained in the L2-norm with order O(τ+hk+1+Hk+2). The numerical experiment is provided to demonstrate the efficiency of the algorithm.
The Impact of Sentiment Indices on the Stock Exchange—The Connections between Quantitative Sentiment Indicators, Technical Analysis, and Stock Market
Authors: Dumiter Florin Cornel , Turcaș Florin , Nicoară Ștefania Amalia , Bențe Cristian , Boiță Marius
Published: July 2023

The stock market represents one of the most complex mechanisms in the financial world. It can be seen as a living being with complex ways to enact, interact, evolve, defend, and respond to various stimuli. Technical analysis is one of the most complex techniques based on financial data’s graphical aspects. News sentiment indices are very complex and highlight another important part of behavioral finance. In this study, we propose an integrated approach in order to determine the correlation between news sentiment indices, the stock market, and technical analysis. The research methodology focuses on the stock market’s practical and quantitative aspects. In this sense, we have used the graphical representation of technical analysis and econometric modeling techniques such as VAR and Bayesian VAR. The results of the empirical modeling techniques and analysis reveal some important connections between the stock market and news sentiment indices on the US stock market. The conclusions of this study highlight a strong connection between news sentiment indices, technical analysis, and the stock market which suggests that the behavioral finance aspect is a very important aspect in the analysis of the stock market.
Classical Solutions of Hyperbolic Equation with Translation Operators in Free Terms
Authors: Vasilyev Vladimir , Zaitseva Natalya
Published: July 2023

In this paper, we study the question of constructing explicit solutions in a half-space of a hyperbolic equation containing translation operators in space variables in all coordinate directions. Such equations are a natural generalization of classical equations of hyperbolic type, and the resulting solution relates the value of the desired function at different points of the half-space where the process takes place. To construct solutions, a classical operating scheme is used, namely, the formal application of an integral transformation. A theorem is proved that the constructed solutions are classical if the real part of the symbol of the differential-difference operator in the equation is positive. Classes of equations for which this condition is satisfied are given.
Global Dynamics of Viral Infection with Two Distinct Populations of Antibodies
Authors: Elaiw Ahmed M. , Raezah Aeshah A. , Alshaikh Matuka A.
Published: July 2023

This paper presents two viral infection models that describe dynamics of the virus under the effect of two distinct types of antibodies. The first model considers the population of five compartments, target cells, infected cells, free virus particles, antibodies type-1 and antibodies type-2. The presence of two types of antibodies can be a result of secondary viral infection. In the second model, we incorporate the latently infected cells. We assume that the antibody responsiveness is given by a combination of the self-regulating antibody response and the predator–prey-like antibody response. For both models, we verify the nonnegativity and boundedness of their solutions, then we outline all possible equilibria and prove the global stability by constructing proper Lyapunov functions. The stability of the uninfected equilibrium EQ0 and infected equilibrium EQ* is determined by the basic reproduction number R0. The theoretical findings are verified through numerical simulations. According to the outcomes, the trajectories of the solutions approach EQ0 and EQ* when R0≤1 and R0>1, respectively. We study the sensitivity analysis to show how the values of all the parameters of the suggested model affect R0 under the given data. The impact of including the self-regulating antibody response and latently infected cells in the viral infection model is discussed. We showed that the presence of the self-regulating antibody response reduces R0 and makes the system more stabilizable around EQ0. Moreover, we established that neglecting the latently infected cells in the viral infection modeling leads to the design of an overflow of antiviral drug therapy.
Modeling Significant Wave Heights for Multiple Time Horizons Using Metaheuristic Regression Methods
Authors: Ikram Rana Muhammad Adnan , Cao Xinyi , Parmar Kulwinder Singh , Kisi Ozgur , Shahid Shamsuddin , Zounemat-Kermani Mohammad
Published: July 2023

The study examines the applicability of six metaheuristic regression techniques—M5 model tree (M5RT), multivariate adaptive regression spline (MARS), principal component regression (PCR), random forest (RF), partial least square regression (PLSR) and Gaussian process regression (GPR)—for predicting short-term significant wave heights from one hour to one day ahead. Hourly data from two stations, Townsville and Brisbane Buoys, Queensland, Australia, and historical values were used as model inputs for the predictions. The methods were assessed based on root mean square error, mean absolute error, determination coefficient and new graphical inspection methods (e.g., Taylor and violin charts). On the basis of root mean square error (RMSE), mean absolute error (MAE), and coefficient of determination (R2) statistics, it was observed that GPR provided the best accuracy in predicting short-term single-time-step and multi-time-step significant wave heights. On the basis of mean RMSE, GPR improved the accuracy of M5RT, MARS, PCR, RF and PLSR by 16.63, 8.03, 10.34, 3.25 and 7.78% (first station) and by 14.04, 8.35, 13.34, 3.87 and 8.30% (second station) for the test stage.
Highly Uniform Multi-Layers Reduced Graphene Oxide/Poly-2-aminobenzene-1-thiol Nanocomposite as a Promising Two Electrode Symmetric Supercapacitor under the Effect of Absence and Presence of Porous-Sphere Polypyrrole Nanomaterial
Authors: Rabia Mohamed , Elsayed Asmaa M. , Salem Ahmed M. , Abdallah Alnuwaiser Maha
Published: July 2023

A uniform and highly porous reduced graphene oxide/poly-2-aminobenzene-1-thiol multi-layer (R-GO/P2ABT-ML) nanocomposite was synthesized and characterized. The uniform layer structure and porosity of the nanocomposite, combined with its conductivity, make it an ideal candidate for use as a pseudo supercapacitor. To enhance the capacitance behavior, a porous ball structure polypyrrole (PB-Ppy) was incorporated into the nanocomposite. When tested at 0.2 A/g, the capacitance values of the R-GO/P2ABT-ML and R-GO/P2ABT-ML/PB-Ppy were found to be 19.6 F/g and 92 F/g, respectively, indicating a significant increase in capacitance due to the addition of PB-Ppy. The energy density was also found to increase from 1.18 Wh.kg−1 for R-GO/P2ABT-ML to 5.43 Wh.kg−1 for R-GO/P2ABT-ML/PB-Ppy. The stability of the supercapacitor was found to be significantly enhanced by the addition of PB-Ppy. The retention coefficients at 100 and 500 charge cycles for R-GO/P2ABT-ML/PB-Ppy were 95.6% and 85.0%, respectively, compared to 89% and 71% for R-GO/P2ABT-ML without PB-Ppy. Given the low cost, mass production capability, and easy fabrication process of this pseudo capacitor, it holds great potential for commercial applications. Therefore, a prototype of this supercapacitor can be expected to be synthesized soon.
Uncertainty Estimation for the Brillouin Frequency Shift Measurement Using a Scanning Tandem Fabry–Pérot Interferometer
Authors: Salzenstein Patrice , Wu Thomas Y.
Published: July 2023

The expanded uncertainty of the measured Brillouin scattering shift frequencies is essential in assessing the measurements of parameters of various materials. We describe the general operation principles of a Brillouin light scattering (BLS) spectrometer with a high-power laser and a scanning tandem Fabry–Pérot interferometer (TFPI) for material characterization. Various uncertainty components have been analyzed for the BLS spectrometer following the Guide to the Expression of Uncertainty in Measurement (GUM). The expanded relative uncertainty in the measured Brillouin frequency shift of 15.70 GHz for polymethyl methacrylate (PMMA) was estimated to be 0.26%. The calculated Brillouin frequency shift (based on material properties of PMMA) was determined to be 15.44 GHz with expanded relative uncertainty of 2.13%. It was shown that the measured and calculated Brillouin frequency shifts for PMMA agree within their expanded uncertainties. The TFPI-based BLS spectrometer can be used to measure the longitudinal modulus of materials with an expanded uncertainty of 1.9%, which is smaller than that of the ultrasonic velocity-based method (estimated to be 2.9%).
Fabrication of High Aspect Ratio Nano-Channels by Thermal Nano-Imprinting and Parylene Deposition
Authors: Yang Kun , Yin Zhifu , Sun Lei
Published: July 2023

A low-cost method of fabrication of high aspect ratio nano-channels by thermal nano-imprinting and Parylene deposition is proposed. SU-8 photoresist nano-channels were first manufactured by thermal nano-imprinting, and Parylene deposition was carried out to reduce the width of the nano-channels and increase the aspect ratio. During the process, the side walls of the SU-8 nano-channels were covered with the Parylene film, reducing the width of the nano-channels, and the depth of the channels increased due to the thickness of the Parylene film deposited on the surface of the SU-8 nano-channels, more so than that at the bottom. The influence of Parylene mass on the size of nano-channels was studied by theoretical analysis and experiments, and the deposition pressure of Parylene was optimized. The final high aspect ratio nano-channels are 46 nm in width and 746 nm in depth, of which the aspect ratio is 16. This simple and efficient method paves the way for the production of high aspect ratio nano-channels.
Systematic Literature Review of the Epidemiological Characteristics of Pneumococcal Disease Caused by the Additional Serotypes Covered by the 20-Valent Pneumococcal Conjugate Vaccine
Authors: Méroc Estelle , Fletcher Mark A. , Hanquet Germaine , Slack Mary P. E. , Baay Marc , Hayford Kyla , Gessner Bradford D. , Grant Lindsay R.
Published: July 2023

Higher valency pneumococcal conjugate vaccines (PCV15 and PCV20) have been developed to address the disease burden of current non-vaccine serotypes. This review describes the epidemiological characteristics of serotypes beyond PCV13 (serotypes 8, 10A, 11A, 12F, 15B/C, 22F, and 33F; PCV20nonPCV13 serotypes). Peer-reviewed studies published between 1 January 2010 (the year PCV13 became available) and 18 August 2020 were systematically reviewed (PROSPERO number: CRD42021212875). Data describing serotype-specific outcomes on disease proportions, incidence, severity, and antimicrobial non-susceptibility were summarized for individual and aggregate PCV20nonPCV13 serotypes by age group and by type and duration of pediatric PCV immunization program. Of 1168 studies, 127 (11%) were included in the analysis. PCV20nonPCV13 serotypes accounted for 28% of invasive pneumococcal disease (IPD), although the most frequent serotypes differed between children (10A, 15B/C) and adults (8, 12F, 22F). In children, serotype 15B/C tended to be more frequently associated with pneumococcal meningitis and acute otitis media; in adults, serotype 8 was more frequently associated with pneumonia and serotype 12F with meningitis. Serotypes 10A and 15B/C in children and 11A and 15B/C in adults were often associated with severe IPD. Serotype 15B/C was also among the most frequently identified penicillin/macrolide non-susceptible PCV20nonPCV13 serotypes. These results could inform decision making about higher valency PCV choice and use.
Characterization and Liberation Study of the Beauvoir Granite for Lithium Mica Recovery
Authors: Demeusy Bastien , Arias-Quintero Carlos Andrés , Butin Gaëlle , Lainé Juliette , Tripathy Sunil Kumar , Marin Jérôme , Dehaine Quentin , Filippov Lev O.
Published: July 2023

A significant proportion of Europe’s lithium endowment is hosted by unconventional lithium resources such as rare-metal granites (RMG) of which the Beauvoir granite in France is a prime example. In such hard-rock deposits, where lithium is mostly hosted in micas (lepidolite, zinnwaldite), the ability to assess whether lithium can be extracted economically from the ore is essential and requires a comprehensive understanding of mineralogical properties and lithium deportment. Using three exploratory drill cores distributed along the North–South axis, a preliminary geometallurgical assessment of the granite has been conducted based on a combination of techniques including Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES), Atomic Adsorption Spectroscopy (AAS), Electron Probe Microanalysis (EPMA), Scanning Electron Microscope (SEM) coupled with automated mineralogy software, X-Ray Diffraction (XRD), optical microscope and sieving. Lithium distribution appears to be variable, reflecting the evolution of the granite, with higher mica content in the southern area and higher Li grade towards the center of the orebody. The size of micas in the assessed sample does not vary significantly. The grindability and liberation size of micas varies in the different zones investigated, PERC S being the most difficult to grind. There is always more than 50 wt% of the micas that are liberated in the samples when crushed to 1 mm. Indirect estimation of Li content based on EPMA and SEM analysis suggests that the content of lithium inside mica crystals could vary. If this estimation is confirmed by direct Li measurement, it for sure makes the calculations of the Li deportment more challenging.
An Estimation of the Antiviral Activity and Toxicity of Biologically Active Substances Obtained from the Raw Materials of Artemisia cina Berg. In Vitro and In Vivo
Authors: Zhurinov Murat , Berillo Dmitriy , Bazhykova Kulzada Begalinovna , Rakhimov Kayrolla Dyusenbaevich , Bekezhanova Tolkyn
Published: July 2023

Species of the genus Artemisia are well known for their use as ingredients in ancient medicine. The advantage of using plant extracts compared to individual pharmaceutical ingredients is the rate of adaptation of the pathogenic microorganisms to the drug. Due to the rapid development of multidrug-resistance in microorganisms in the field, it is essential to search for novel, effective drugs with low toxicity. Therefore, the purpose of this study was to isolate and study the biologically active substances obtained from various substances in the raw materials of Artemisia cina Berg. The identification of the main biologically active components was performed using the method of chromato-mass spectrometry. Moreover, the antiviral activity of several extracts was studied using the method of measuring limiting dilutions (the Reed–Mench method), with some modifications. For the first time, the biological activity of extracts from the raw material of Artemisia cina Berg. upon the SARS-CoV-2 virus was confirmed. All the obtained extracts exhibited nontoxic effects in animals, with an LD50 greater than 2 g/kg. Comprehensive toxicological analyses are also presented in the study, such as those of the biochemical parameters of urine after one day and one week of the extracts’ administration in mice at a dose of 2 g/kg body weight. In all groups of animals that received extracts of Artemisia cina Berg., a slight increase in the presence of red blood cells in their urine was observed one day following the administration of the extracts. This increase decreased somewhat after a week; however, it remained higher than the levels observed in the control animals. In the three groups, there was also a slight increase in the amount of ketones in the urine. Two weeks following the administration of the extracts to these groups, the internal organs of the animals were examined. The examination showed that the internal organs of the animals that received the extracts were not visibly different from those of the control animals in terms of their size or appearance. The weight of the internal organs of the animals that received the extracts was also similar to the weight of the internal organs of the control animals, illustrating the absence of toxicity.
New Phenolic Lipids from the Leaves of Clausena harmandiana Inhibit SARS-CoV-2 Entry into Host Cells
Authors: Chambon Marion , Herrscher Charline , Al Halabi Dana , François Nathan , Belouzard Sandrine , Boutet Stéphanie , Pham Van Cuong , Doan Thi Mai Huong , Séron Karin , Mavingui Patrick , Litaudon Marc , El Kalamouni Chaker , Apel Cécile
Published: July 2023

Induced by the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the COVID-19 pandemic underlined the clear need for antivirals against coronaviruses. In an effort to identify new inhibitors of SARS-CoV-2, a screening of 824 extracts prepared from various parts of 400 plant species belonging to the Rutaceae and Annonaceae families was conducted using a cell-based HCoV-229E inhibition assay. Due to its significant activity, the ethyl acetate extract of the leaves of Clausena harmandiana was selected for further chemical and biological investigations. Mass spectrometry-guided fractionation afforded three undescribed phenolic lipids (1–3), whose structures were determined via spectroscopic analysis. The absolute configurations of 1 and 2 were determined by analyzing Mosher ester derivatives. The antiviral activity against SARS-CoV-2 was subsequently shown, with IC50 values of 0.20 and 0.05 µM for 2 and 3, respectively. The mechanism of action was further assessed, showing that both 2 and 3 are inhibitors of coronavirus entry by acting directly on the viral particle. Phenolic lipids from Clausena harmandiana might be a source of new antiviral agents against human coronaviruses.
Different Structures—Similar Effect: Do Substituted 5-(4-Methoxyphenyl)-1H-indoles and 5-(4-Methoxyphenyl)-1H-imidazoles Represent a Common Pharmacophore for Substrate Selective Inhibition of Linoleate Oxygenase Activity of ALOX15?
Authors: Zhuravlev Alexander , Cruz Alejandro , Aksenov Vladislav , Golovanov Alexey , Lluch José M. , Kuhn Hartmut , González-Lafont Àngels , Ivanov Igor
Published: July 2023

Mammalian 15-lipoxygenases (ALOX15) are lipid peroxidizing enzymes that exhibit variable functionality in different cancer and inflammation models. The pathophysiological role of linoleic acid- and arachidonic acid-derived ALOX15 metabolites rendered this enzyme a target for pharmacological research. Several indole and imidazole derivatives inhibit the catalytic activity of rabbit ALOX15 in a substrate-specific manner, but the molecular basis for this allosteric inhibition remains unclear. Here, we attempt to define a common pharmacophore, which is critical for this allosteric inhibition. We found that substituted imidazoles induce weaker inhibitory effects when compared with the indole derivatives. In silico docking studies and molecular dynamics simulations using a dimeric allosteric enzyme model, in which the inhibitor occupies the substrate-binding pocket of one monomer, whereas the substrate fatty acid is bound at the catalytic center of another monomer within the ALOX15 dimer, indicated that chemical modification of the core pharmacophore alters the enzyme–inhibitor interactions, inducing a reduced inhibitory potency. In our dimeric ALOX15 model, the structural differences induced by inhibitor binding are translated to the hydrophobic dimerization cluster and affect the structures of enzyme–substrate complexes. These data are of particular importance since substrate-specific inhibition may contribute to elucidation of the putative roles of ALOX15 metabolites derived from different polyunsaturated fatty acids in mammalian pathophysiology.
Two-Dimensional NMR Spectroscopy of the G Protein-Coupled Receptor A2AAR in Lipid Nanodiscs
Authors: Guo Canyong , Yang Lingyun , Liu Zhijun , Liu Dongsheng , Wüthrich Kurt
Published: July 2023

Eight hundred and twenty-six human G protein-coupled receptors (GPCRs) mediate the actions of two-thirds of the human hormones and neurotransmitters and over one-third of clinically used drugs. Studying the structure and dynamics of human GPCRs in lipid bilayer environments resembling the native cell membrane milieu is of great interest as a basis for understanding structure–function relationships and thus benefits continued drug development. Here, we incorporate the human A2A adenosine receptor (A2AAR) into lipid nanodiscs, which represent a detergent-free environment for structural studies using nuclear magnetic resonance (NMR) in solution. The [15N,1H]-TROSY correlation spectra confirmed that the complex of [u-15N, ~70% 2H]-A2AAR with an inverse agonist adopts its global fold in lipid nanodiscs in solution at physiological temperature. The global assessment led to two observations of practical interest. First, A2AAR in nanodiscs can be stored for at least one month at 4 °C in an aqueous solvent. Second, LMNG/CHS micelles are a very close mimic of the environment of A2AAR in nanodiscs. The NMR signal of five individually assigned tryptophan indole 15N–1H moieties located in different regions of the receptor structure further enabled a detailed assessment of the impact of nanodiscs and LMNG/CHS micelles on the local structure and dynamics of A2AAR. As expected, the largest effects were observed near the lipid–water interface along the intra- and extracellular surfaces, indicating possible roles of tryptophan side chains in stabilizing GPCRs in lipid bilayer membranes.
Anti-Inflammatory Effects of Dietary Polyphenols through Inhibitory Activity against Metalloproteinases
Authors: Suzuki Takuji , Ohishi Tomokazu , Tanabe Hiroki , Miyoshi Noriyuki , Nakamura Yoriyuki
Published: July 2023

Matrix metalloproteinases (MMPs) are zinc-dependent metalloproteinases that play important roles in a variety of diseases, including cancer, cardiovascular disease, diabetes, obesity, and brain diseases. Dietary polyphenols are thought to have a variety of beneficial effects on these diseases characterized by inflammation. Clinical studies have demonstrated that MMPs are in most cases upregulated in various inflammatory diseases, including osteoarthritis, rheumatoid arthritis, inflammatory bowel disease, and Alzheimer’s disease. Studies using patient-derived human samples, animal studies, and cellular experiments have suggested that polyphenols may be beneficial against inflammatory diseases by suppressing MMP gene expression and enzyme activity. One important mechanism by which polyphenols exert their activity is the downregulation of reactive oxygen species that promote MMP expression. Another important mechanism is the direct binding of polyphenols to MMPs and their inhibition of enzyme activity. Molecular docking analyses have provided a structural basis for the interaction between polyphenols and MMPs and will help to explore new polyphenol-based drugs with anti-inflammatory properties.
Faba Bean Processing: Thermal and Non-Thermal Processing on Chemical, Antinutritional Factors, and Pharmacological Properties
Authors: Badjona Abraham , Bradshaw Robert , Millman Caroline , Howarth Martin , Dubey Bipro
Published: July 2023

The food industry, academia, food technologists, and consumers have become more interested in using faba bean seeds in the formulation of new products because of their nutritional content, accessibility, low costs, environmental advantages, and beneficial impacts on health. In this review, a systematic and up-to-date report on faba bean seeds’ antinutrients and bioactive and processing techniques is comprehensively presented. The chemical composition, including the oil composition and carbohydrate constituents, is discussed. Factors influencing the reduction of antinutrients and improvement of bioactive compounds, including processing techniques, are discussed. Thermal treatments (cooking, autoclaving, extrusion, microwaving, high-pressure processing, irradiation) and non-thermal treatments (soaking, germination, extraction, fermentation, and enzymatic treatment) are identified as methods to reduce the levels of antinutrients in faba bean seeds. Appropriate processing methods can reduce the antinutritional factors and enrich the bioactive components, which is useful for the seeds’ efficient utilization in developing functional foods. As a result, this evaluation focuses on the technologies that are employed to reduce the amounts of toxins in faba bean seeds. Additionally, a comparison of these methods is performed in terms of their advantages, disadvantages, viability, pharmacological activity, and potential for improvement using emerging technologies. Future research is expected in this area to fill the knowledge gap in exploiting the nutritional and health benefits of faba bean seeds and increase the utilization of faba bean seeds for different applications.
Effects of Different Freezing Rate and Frozen Storage Temperature on the Quality of Large-Mouth Bass (Micropterus salmoides)
Authors: Bao Yulong , Zhang Yaqi , Xu Wanjun
Published: July 2023

In order to clarify the individual role of freezing and frozen storage on the quality of fish, fillets of large-mouth bass (Micropterus salmoides) were subjected to different freezing rates (freezing with −18 °C (A), −60 °C (B), and −60 °C with forced air circulation at 2 m/s (C), respectively) followed by frozen storage at −18 °C for 30 and 90 days. Another two groups were frozen at −60 °C, followed by storage at −40 °C (D) and −60 °C (E), respectively. Results showed that water-holding and TVBN were mainly affected by storage time. No significant changes were found in free thiol content among treatments. A greater freezing rate and lower storage temperature generally led to lower TBARS. GC × GC-TOFMS revealed a total of 66 volatile compounds, which were related to lipid oxidation. PLS-DA showed that fresh samples were separated from the frozen–thawed ones, and fillets in groups D and E were relatively close to fresh fillets in the composition of oxidation-related volatiles. In conclusion, freezing rate and storage temperature had a significant impact on lipid oxidation and protein denaturation in the fillets of large-mouth bass, while protein oxidation was more affected by freezing rate.
Nano-Formulating Besifloxacin and Employing Quercetin as a Synergizer to Enhance the Potency of Besifloxacin against Pathogenic Bacterial Strains: A Nano-Synergistic Approach
Authors: Al Hagbani Turki , Rizvi Syed Mohd Danish , Shakil Shazi , Lila Amr Selim Abu
Published: July 2023

The present study applied a nano-synergistic approach to enhance besifloxacin’s potency via nano-formulating besifloxacin on gold nanoparticles (Besi-AuNPs) and adding quercetin as a natural synergistic compound. In fact, a one-pot AuNP synthesis approach was applied for the generation of Besi-AuNPs, where besifloxacin itself acted as a reducing and capping agent. Characterization of Besi-AuNPs was performed by spectrophotometry, DLS, FTIR, and electron microscopy techniques. Moreover, antibacterial assessment of pure besifloxacin, Besi-AuNPs, and their combinations with quercetin were performed on Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. UV-spectra showed a peak of AuNPs at 526 nm, and the electron microscopy-based size was estimated to be 15 ± 3 nm. The effective MIC50 concentrations of besifloxacin after loading on AuNPs were reduced by approximately 50% against the tested bacterial strains. Interestingly, adding quercetin to Besi-AuNPs further enhanced their antibacterial potency, and isobologram analysis showed synergistic potential (combination index below 1) for different quercetin and Besi-AuNP combinations. However, Besi-AuNPs and quercetin combinations were most effective against Gram-positive S. aureus in comparison to Gram-negative P. aeruginosa and E. coli. Their potent activity against S. aureus has its own clinical significance, as it is one the main causative agents of ocular infection, and besifloxacin is primarily used for treating infectious eye diseases. Thus, the outcomes of the present study could be explored further to provide better medication for eye infections caused by resistant pathogens.
Defect Localization in Metal Plates Using Vibroacoustic Modulation
Authors: Bazrafkan Mohammad M. , Rutner Marcus
Published: July 2023

This paper reviews the state-of-the-art approaches in defect localization and specifies the remaining questions and challenges. Furthermore, this study presents a novel defect localization methodology using the nonlinear interaction of primary Lamb wave modes and vibroacoustic modulation (VAM), combined with damage imaging, to address the current shortcomings of defect localization. The study investigates this methodology experimentally with respect to defect interpretation, resolution, and applicability. Two Lamb waves with high and low frequencies, one being continuous and the other a tone burst, were excited using two different piezoelectric sensors. The amplitude of the measured signal at the first sideband frequency was evaluated with a short-time Fourier transform (STFT) and used for damage imaging via the delay and sum method. This study also includes a discussion on identifying the source of nonlinearity reflected in the first sideband. The experimental measurements prove that the localization of defect nonlinearity is possible with high accuracy, without the need for a baseline measurement, and with a minimum number of sensors. Sensitivity measurements with respect to the required length of the high-frequency tone burst and the sensor arrangement were also conducted.
The Association of Lifestyle Patterns with Prediabetes in Adults from Families at High Risk for Type 2 Diabetes in Europe: The Feel4Diabetes Study
Authors: Mourouti Niki , Mavrogianni Christina , Mouratidou Theodora , Liatis Stavros , Valve Päivi , Rurik Imre , Torzsa Péter , Cardon Greet , Bazdarska Yulia , Iotova Violeta , Moreno Luis A. , Makrilakis Konstantinos , Manios Yannis
Published: July 2023

The increasing prevalence of prediabetes globally does not bode well for the growing epidemic of type 2 diabetes (T2D) and its complications. Yet there is a lack of studies regarding lifestyle patterns (LPs) and their association with prediabetes. The present study aimed to examine the association of different LPs with the existence of prediabetes in adults from families at high risk for T2D in Europe. In total, 2759 adults (66.3% females) from six European countries were included in this cross-sectional analysis using data from the baseline assessment of the Feel4Diabetes study. Anthropometric, sociodemographic, dietary and behavioral data were assessed, and fasting blood glucose measurements were also obtained. LPs were derived via principal component analysis. Two LPs were derived, explaining 32% of the total variation. LP 1 was characterized by breakfast consumption, high consumption of fruits and berries, vegetables and nuts and seeds, and low consumption of salty snacks and soft drinks with sugar, while LP 2 was characterized by high consumption of salty and sweet snacks, soft drinks with sugar and juice with sugar and sedentary behavior. After adjusting for various confounders, LP 2 was positively associated with the existence of prediabetes (odds ratio = 1.02, 95% CI 1.01–1.04), while LP 1 was not significantly associated with prediabetes. Understanding LPs would provide necessary evidence for planning intervention and education strategies for prediabetes and T2D.
Association between Consumption of Ultra-Processed Food and Body Composition of Adults in a Capital City of a Brazilian Region
Authors: Monteles Nascimento Larisse , de Carvalho Lavôr Layanne Cristina , Mendes Rodrigues Bruna Grazielle , da Costa Campos Felipe , de Almeida Fonseca Viola Poliana Cristina , Lucarini Massimo , Durazzo Alessandra , Arcanjo Daniel Dias Rufino , de Carvalho e Martins Maria do Carmo , de Macêdo Gonçalves Frota Karoline
Published: July 2023

The present study investigates the relationship between the consumption of ultra-processed foods (UPF) and anthropometric indices of body composition in adults and seniors living in Teresina, the state capital of an area in northeastern Brazil. The article seeks to address two questions: Is UPF consumption linked to worsening body composition in different age groups? Do anthropometric indicators of body composition change with the increasing consumption of UPF? The study is a cross-sectional, household, population study, carried out with 490 adults and seniors. The food consumption was obtained with a 24 h food recall, and the foods were classified using NOVA. Anthropometric indicators evaluated were waist-to-height ratio, triceps skinfold thickness, arm circumference, corrected arm muscle area, subscapular skinfold thickness, and calf circumference. The association between energy contribution of UPF with anthropometric indicators was verified with a simple and multiple linear regression analysis. Individuals aged 20 to 35 years showed a significant association between UPF consumption and skinfold thickness (ß: 0.04; CI: 0.03/0.09), demonstrating an increase in this subcutaneous body fat marker with higher UPF consumption. Moreover, in participants aged 36 to 59 years, an inverse correlation between UPF intake and muscle mass markers, arm circumference (ß: −0.02; confidence interval: −0.03/−0.01), and corrected arm muscle area (ß: −0.07; confidence interval: −0.12/−0.02) were observed. Such results suggest there is decreased muscle mass with increasing UPF consumption. This is the first study that verified an association between UPF consumption and low-cost body composition indicators in different age groups.
Precision Medicine Revolutionizing Esophageal Cancer Treatment: Surmounting Hurdles and Enhancing Therapeutic Efficacy through Targeted Drug Therapies
Authors: Panda Poojarani , Verma Henu Kumar , Bhaskar Lakkakula V. K. S.
Published: July 2023

Esophageal cancer is a formidable challenge in the realm of cancer treatment. Conventional methods such as surgery, chemotherapy, and immunotherapy have demonstrated limited success rates in managing this disease. In response, targeted drug therapies have emerged as a promising strategy to improve outcomes for patients. These therapies aim to disrupt specific pathways involved in the growth and development of esophageal cancer cells. This review explores various drugs used to target specific pathways, including cetuximab and monoclonal antibodies (gefitinib) that target the epidermal growth factor receptor (EGFR), trastuzumab that targets human epidermal growth factor receptor 2 (HER-2), drugs targeting the vascular endothelial growth factor receptor (VEGFR), mTOR inhibitors, and cMET inhibitors. Additionally, the article discusses the impact of drug resistance on the effectiveness of these therapies, highlighting factors such as cancer stem cells, cancer-associated fibroblasts, immune-inflammatory cells, cytokines, hypoxia, and growth factors. While drug targeting approaches do not provide a complete cure for esophageal cancer due to drug resistance and associated side effects, they offer potential for improving patient survival rates.