bluuebunny/crossref_metadata_2025 huggingface dataset:
Elaboration of Evaluation Criteria for a Mathematical Model of a Fuel System in a Light Helicopter
Authors: Talalaeva Polina , Starostin Konstantin , Savelyev Roman
Published: February 2023

In this article, a calculation model for a fuel system of a light helicopter was developed for experimental and operational testing. The model analyzes the operation of not only the units, but also the whole fuel system, offering the basis for functional tests and failure detection. For an actual model-based design, it is necessary to ensure that the model conforms to a real object or process. This article addressed the problems of ensuring the accuracy of the calculation and the computational speed when developing a reliable mathematical model of an actual technological system using structural modeling methods. A system with evaluation criteria allows complex field tests to be replaced with validated calculation models.
Numerical Investigation of Mach 2.5 Axisymmetric Turbulent Shock Wave Boundary Layer Interactions
Authors: Mosele John-Paul , Gross Andreas , Slater John
Published: February 2023

Shock wave boundary layer interactions are common to both supersonic and hypersonic inlet flows. Wall-resolved implicit large-eddy simulations of a canonical Mach 2.5 axisymmetric shock wave boundary layer interaction experiment at Glenn Research Center were carried out. A conical shock wave was generated with axisymmetric centerbodies with 16 deg half-angle cone. The centerbody radii were 9.2% and 14.7% of the test section diameter. The conical shock wave interacted with the turbulent boundary layer on the inside of the cylindrical test section. The experimental Reynolds number based on diameter was six million. For the simulations, the Reynolds number was reduced by a factor of 10 to lower the computational expense. The turbulent boundary layer separates for both centerbody radii and the separation is stronger for the larger centerbody radius. Frequency spectra of the spanwise-averaged wall-pressure coefficient reveal low-frequency content at Strouhal numbers based on separation length between 0.02 and 0.05 in the vicinity of the separation shock and mid-frequency content between 0.1 and 0.2 downstream of separation. A proper orthogonal decomposition captures spanwise coherent structures with a Strouhal number of 0.03–0.04 over the interaction region and streamwise coherent structures inside and downstream of the interaction with a Strouhal number of 0.1–0.4.
Micro Turbojet Engine Nozzle Ejector Impact on the Acoustic Emission, Thrust Force and Fuel Consumption Analysis
Authors: Cican Grigore , Frigioescu Tiberius-Florian , Crunteanu Daniel-Eugeniu , Cristea Laurentiu
Published: February 2023

This paper explores the implementation of an ejector to a micro turbojet engine and analysis of the advantages in terms of acoustic and thrust/fuel consumption. Starting with the analytical equations and a series of numerical simulations, the optimal ejector geometry for maximum thrust was obtained. The ejector was manufactured and integrated with the Jet Cat P80 micro turbo engine for testing. The purpose of this article is to report on an improved geometry that results in no significant increase in the frontal area of the turbo engine, which could increase drag. The tests were completed using various functioning regimes, namely idle, cruise and maximum. For each of them, a comparative analysis between engine parameters with and without an ejector was performed. During the experiments, it was observed that, when the ejector was used, the thrust increased for each regime, and the specific consumption decreased for all regimes. The stability of the engine was tested in transient regimes by performing a sudden acceleration sequence, and one carried out the operating line and the modification of temperature values in front of the turbine for both configurations. For each regime, the acoustic noise was monitored at a few points that were different distances from the nozzle, and a decrease was identified when the ejector was used. The advantages of using the ejector on the Jet Cat P80 turbo jet engine are an increased thrust, a lower specific consumption and a reduced noise level, and at the same time, the integrity of the engine in stable operational states and transient operating regimes is not affected.
Genetic Diversity of Korean Black Soybean (Glycine max L.) Germplasms with Green Cotyledons Based on Seed Composition Traits
Authors: Lee Ji Yun , Jo Hyun , Son Chang Ki , Bae Jeong Suk , Lee Jeong-Dong
Published: February 2023

The demand for black soybeans (Glycine max (L.) Merr.) with green cotyledons is increasing because of their health benefits. Therefore, it is important to understand the genetic diversity of black soybean germplasms and to develop a new soybean cultivar. This study aimed to evaluate genetic diversity among 469 black soybean germplasms with green cotyledons based on seed composition traits. Twenty seed composition traits were analyzed to conduct correlation analysis, principal component analysis (PCA), and cluster analysis, which indicated that black soybean germplasms were divided into four clusters. Black soybean germplasms in cluster 1 had higher crude fat, lutein, chlorophyll a, chlorophyll b, and total chlorophyll contents, but lower cyanidin-3-glucoside content than those in clusters 2 and 3. However, germplasms in clusters 2 and 3 had the highest cyanidin-3-glucoside content. Moreover, germplasms in cluster 1 had significantly higher palmitic acid content than those in clusters 2 and 3. Germplasms in clusters 2 and 3 had relatively high α-linolenic acid content. Germplasms in cluster 4 had the highest oleic acid content. This study highlights the genetic diversity of black soybean germplasms with different seed composition traits, and the results of this study can be beneficial for soybean breeding programs, enabling them to develop new black soybean cultivars with green cotyledons and improved seed composition traits.
Changes in Protein Metabolism Indicators in Dairy Cows with Naturally Occurring Mycotoxicosis before and after Administration of a Mycotoxin Deactivator
Authors: Marczuk Jan , Brodzki Piotr , Brodzki Adam , Głodkowska Katarzyna , Wrześniewska Karolina , Brodzki Nikodem
Published: February 2023

The aim of the study was to evaluate selected indicators of protein metabolism in cows fed with fodder contaminated with mycotoxins after application of a mycotoxin deactivator product (MDP). Experimental group (Exp.)—10 cows, fed total mixed ration (TMR) containing: 0.769 mg/kg-deoxynivalenol and 0.032 mg/kg-zearalenone TMR DM. Control group (Con.)—10 cows fed TMR without mycotoxins. In the exp. cows, the mycotoxin deactivator product (MDP) Mycofix Plus was used in the form of an additive to TMR in the amount of 10 g/head/day for 90 days. Blood was taken in Exp. group three times, before MDP administration, and on days 30 and 90 of its use. In the con. group, blood was collected once. All cows were assessed for free amino acids, total protein, albumin, globulin, and urea. Cows with mycotoxicosis (before MDP administration) showed low total protein, albumin, total-essential (TEAA) and total-non-essential amino acids (TNEAA) compared to after MDP administration (p < 0.01). Compared to the control group, TNEAA values were lower and TEAA higher on all study dates (p < 0.001). The results of our research showed the negative impact of mycotoxins on the parameters of protein metabolism in cows, and the use of MDP improved the processes of protein metabolism and improved the overall health of cows.
Evaluation of Piperacillin/Sulbactam, Piperacillin/Tazobactam and Cefoperazone/Sulbactam Dosages in Gram-Negative Bacterial Bloodstream Infections by Monte Carlo Simulation
Authors: Wang Xueting , Xiong Luying , Yu Wei , Huang Chen , Ji Jinru , Ying Chaoqun , Liu Zhiying , Chen Yunbo , Xiao Yonghong
Published: February 2023

The optimal regimens of piperacillin/sulbactam (PIS 2:1), piperacillin/tazobactam (PTZ 8:1), and cefoperazone/sulbactam (CSL 2:1) are not well defined in patients based on renal function. This study was conducted to identify optimal regimens of BLBLIs in these patients. The antimicrobial sensitivity test was performed by a two-fold agar dilution method. Monte Carlo simulation (MCS) was used to simulate the probability of target attainment (PTA) and the cumulative fraction of response (CFR) for various dosing regimens in patients with different renal functions. For strains with an MIC ≤ 8/4 mg/L, PIS 4.5 g q6h achieved 99.03%PTA in the subset of patients with creatinine clearance (CrCL) > 90 mL/min. For patients with CrCL 60–90 mL/min, PIS 4.5 g q6h achieved 81.2% CFR; for those with CrCL 40–59 mL/min, PIS 4.5 g q8h achieved 80.25% CFR. However, for patients infected by ESBL-producing Enterobacteriaceae, PIS 4.5 g q6h achieved a CFR lower than 80%. For patients infected by A. baumannii with a CrCL of 31–60 mL/min, PIS 6.0 g q8h and 4.5 g q6h achieved 81.24% and 82.42% CFR, respectively. For those infected by P. aeruginosa, PIS 4.5 g q6h reached 90% CFR. PIS and PTZ achieved a similar CFR when piperacillin was at the same dose. The CFRs of CSL were much lower than those of the other two agents in Enterobacteriaceae and P. aeruginosa infections. The antibacterial spectrum of PIS is superior to that of PTZ and CSL. Higher dosages and dosing adjustment according to renal function should be considered to treat Gram-negative bacterial BSIs.
Antimicrobial Resistance, SCCmec, Virulence and Genotypes of MRSA in Southern China for 7 Years: Filling the Gap of Molecular Epidemiology
Authors: Liu Junyan , Huang Tengyi , Soteyome Thanapop , Miao Jian , Yu Guangchao , Chen Dingqiang , Ye Congxiu , Yang Ling , Xu Zhenbo
Published: February 2023

As the prevalence of Staphylococcus aureus infections is of worldwide concern, phenotype and genotype in prevalent MRSA strains require longitudinal investigation. In this study, the antibiotic resistance, virulence gene acquisition, and molecular type were determined on a large scale of nosocomial S. aureus strains in Southern China during 2009–2015. Bacterial identification and antimicrobial susceptibility to 10 antibiotics were tested by Vitek-2. Virulence genes encoding staphylococcal enterotoxins (SEA, SEB, SEC, SED, and SEE), exfoliative toxins (ETA and ETB), Panton–Valentine leukocidin (PVL), and toxic shock syndrome toxin (TSST) were detected by PCR, with SCCmec typing also conducted by multiplex PCR strategy. Genotypes were discriminated by MLST and spaA typing. MLST was performed by amplification of the internal region of seven housekeeping genes. PCR amplification targeting the spa gene was performed for spa typing. No resistance to vancomycin, linezolid, or quinupristin and increase in the resistance to trimethoprim/sulfamethoxazole (55.5%) were identified. A total of nine SCCmec types and subtypes, thirteen STs clustered into thirteen spa types were identified, with ST239-SCCmec III-t037 presenting the predominant methicillin-resistant S. aureus (MRSA) clone. Typically, SCCmec type IX and ST546 were emergent types in China. Isolates positive for both pvl and tsst genes and for both eta and etb genes were also identified. Important findings in this study include: firstly, we have provided comprehensive knowledge on the molecular epidemiology of MRSA in Southern China which fills the gap since 2006 or 2010 from previous studies. Secondly, we have presented the correlation between virulence factors (four major groups) and genotypes (SCCmec, ST and spa types). Thirdly, we have shown evidence for earliest emergence of type I SCCmec from 2012, type VI from 2009 and type XI from 2012 in MRSA from Southern China.
Electronegative LDL Is Associated with Plaque Vulnerability in Patients with Ischemic Stroke and Carotid Atherosclerosis
Authors: Puig Núria , Camps-Renom Pol , Solé Arnau , Aguilera-Simón Ana , Jiménez-Xarrié Elena , Fernández-León Alejandro , Camacho Mercedes , Guasch-Jiménez Marina , Marin Rebeca , Martí-Fàbregas Joan , Martínez-Domeño Alejandro , Prats-Sánchez Luis , Casoni Francesca , Pérez Belén , Jiménez-Altayó Francesc , Sánchez-Quesada Jose Luis , Benitez Sonia
Published: February 2023

Owing to the high risk of recurrence, identifying indicators of carotid plaque vulnerability in atherothrombotic ischemic stroke is essential. In this study, we aimed to identify modified LDLs and antioxidant enzymes associated with plaque vulnerability in plasma from patients with a recent ischemic stroke and carotid atherosclerosis. Patients underwent an ultrasound, a CT-angiography, and an 18F-FDG PET. A blood sample was obtained from patients (n = 64, 57.8% with stenosis ≥50%) and healthy controls (n = 24). Compared to the controls, patients showed lower levels of total cholesterol, LDL cholesterol, HDL cholesterol, apolipoprotein B (apoB), apoA-I, apoA-II, and apoE, and higher levels of apoJ. Patients showed lower platelet-activating factor acetylhydrolase (PAF-AH) and paraoxonase-1 (PON-1) enzymatic activities in HDL, and higher plasma levels of oxidized LDL (oxLDL) and electronegative LDL (LDL(−)). The only difference between patients with stenosis ≥50% and <50% was the proportion of LDL(−). In a multivariable logistic regression analysis, the levels of LDL(−), but not of oxLDL, were independently associated with the degree of carotid stenosis (OR: 5.40, CI: 1.15–25.44, p < 0.033), the presence of hypoechoic plaque (OR: 7.52, CI: 1.26–44.83, p < 0.027), and of diffuse neovessels (OR: 10.77, CI: 1.21–95.93, p < 0.033), indicating that an increased proportion of LDL(−) is associated with vulnerable atherosclerotic plaque.
Improving the Aromatic Profiles of Catarratto Wines: Impact of Metschnikowia pulcherrima and Glutathione-Rich Inactivated Yeasts
Authors: Naselli Vincenzo , Prestianni Rosario , Badalamenti Natale , Matraxia Michele , Maggio Antonella , Alfonzo Antonio , Gaglio Raimondo , Vagnoli Paola , Settanni Luca , Bruno Maurizio , Moschetti Giancarlo , Francesca Nicola
Published: February 2023

Catarratto is one of the most widely cultivated grape varieties in Sicily. It is an indigenous non-aromatic white grape variety. Despite its widespread use in winemaking, knowledge of the aroma and chemical and microbiological properties of Catarratto wines is quite limited. The influence of Metschnikowia pulcherrima combined with Saccharomyces cerevisiae on the aromatic expression of Catarratto wines was investigated with and without the addition of glutathione-rich inactivated yeast. The substance is a natural specific inactivated yeast with a guaranteed glutathione level used to limit oxidative processes. The aromatic profiles of the final wines were determined through analysis of the volatile organic compounds using a solid-phase microextraction technique that identified 26 aromatic compounds. The addition of M. pulcherrima in combination with the natural antioxidant undoubtedly increased the aromatic complexity of the wines. Dodecanal was exclusively detected in the wines processed with glutathione-rich inactivated yeasts. Furthermore, the presence of this natural antioxidant increased the concentration of six esters above the perception threshold. Sensory analysis was also performed with a panel of trained judges who confirmed the aromatic differences among the wines. These results suggest the suitability of glutathione-rich inactivated yeasts for determining the oxidative stability of Catarratto wines, thus preserving its aromatic compounds and colour.
Freeze-Drying Microencapsulation of Hop Extract: Effect of Carrier Composition on Physical, Techno-Functional, and Stability Properties
Authors: Tatasciore Simona , Santarelli Veronica , Neri Lilia , González Ortega Rodrigo , Faieta Marco , Di Mattia Carla Daniela , Di Michele Alessandro , Pittia Paola
Published: February 2023

In this study, freeze-drying microencapsulation was proposed as a technology for the production of powdered hop extracts with high stability intended as additives/ingredients in innovative formulated food products. The effects of different carriers (maltodextrin, Arabic gum, and their mixture in 1:1 w/w ratio) on the physical and techno-functional properties, bitter acids content, yield and polyphenols encapsulation efficiency of the powders were assessed. Additionally, the powders’ stability was evaluated for 35 days at different temperatures and compared with that of non-encapsulated extract. Coating materials influenced the moisture content, water activity, colour, flowability, microstructure, and water sorption behaviour of the microencapsulates, but not their solubility. Among the different carriers, maltodextrin showed the lowest polyphenol load yield and bitter acid content after processing but the highest encapsulation efficiency and protection of hop extracts’ antioxidant compounds during storage. Irrespective of the encapsulating agent, microencapsulation did not hinder the loss of bitter acids during storage. The results of this study demonstrate the feasibility of freeze-drying encapsulation in the development of functional ingredients, offering new perspectives for hop applications in the food and non-food sectors.
Isolation, Physicochemical Characterization, and Biological Properties of Inotodiol, the Potent Pharmaceutical Oxysterol from Chaga Mushroom
Authors: Nguyen Phu Cuong , Nguyen My Tuyen Thi , Truong Ba Tai , Kim Dae-Ryeol , Shin Sujin , Kim Ju-Eun , Park Kyu-Been , Park Ji-Hyun , Tran Phuong Lan , Ban So-Young , Kim Jaehan , Park Jong-Tae
Published: February 2023

Inotodiol, an oxysterol found only in Chaga mushroom, has received attention from the pharmaceutical industry due to its strong antioxidant and anti-allergic activities. However, the production of inotodiol is still challenging, and its fundamental properties have yet to be investigated. This study aims to develop an efficient method to produce high-purity inotodiol from Chaga mushroom. Then, pure inotodiol was used to assess its physicochemical properties and biological activities. By optimizing the solvent used for extraction and purification, a new method to produce inotodiol was developed with high purity (>97%) and purification yield (33.6%). Inotodiol exhibited a melting point (192.06 °C) much higher than lanosterol and cholesterol. However, the solubility of inotodiol in organic solvents was notably lower than those of the other two sterols. The difference in the hydroxyl group at C-22 of inotodiol has shown the distinctive physicochemical properties of inotodiol compared with cholesterol and lanosterol. Based on those findings, a nonionic surfactant-based delivery system for inotodiol was developed to improve its bioavailability. The inotodiol microemulsion prepared with 1–2% Tween-80 exhibited homogenous droplets with an acceptable diameter (354 to 217 nm) and encapsulation efficiency (85.6–86.9%). The pharmacokinetic analysis of inotodiol microemulsion in oral administration of 4.5 mg/kg exhibited AUC0–24h = 341.81 (ng·h/mL), and Cmax = 88.05 (ng/mL). Notably, when the dose increased from 4.5 to 8.0 mg/kg, the bioavailability of inotodiol decreased from 41.32% to 33.28%. In a mouse model of sepsis, the serum level of interleukin-6 significantly decreased, and the rectal temperature of mice was recovered in the inotodiol emulsion group, indicating that inotodiol microemulsion is an effective oral delivery method. These results could provide valuable information for applying inotodiol in functional food, cosmetic, and pharmaceutical industries.
CAE Prediction for Compression Behavior in Multi-Stacked Packages with an EPS-Based Cushioning System: Modeling of Compression and Compressive Creep Behavior
Authors: Park Jong Min , Lee Gun Yeop , Kim Dong Hyun , Jung Hyun Mo
Published: February 2023

The compression and compressive creep behavior of target shipping containers, which are material properties based on finite element analysis, and the lifetime and load-sharing rate, were analyzed in this study to develop a computer-aided engineering prediction technology for predicting the multi-stage compression behavior of three target packages with different logistics conditions. In the experiment performed in the study, the relative humidity levels were 50%, 70%, and 90%, with creep measurements performed for 12 h for a combination of three levels of applied load and relative humidity. Using the nonlinear model of the stress–strain and creep behavior of the target shipping container, the lifetime was analyzed by estimating the average creep rate of the target shipping container. The load-sharing rate for each logistics situation of the target packages was also analyzed. The reduction rate of the compression strength of the container with respect to the increase in relative humidity was greater in the ‘horizontal long’ container than in the ‘vertical long’ container. As the applied load increased, the rate of increase in the average creep rate increased, i.e., the higher the applied load, the larger the difference in the average creep rate with respect to the relative humidity. The lifetime estimated from the failure strain and average creep rate of the container gradually decreased as the applied load increased at all relative humidity levels. However, as the applied load increased, the difference with respect to the relative humidity tended to decrease. In the target packages used in this study, the ratio of the load-sharing rate between the shipping container and an expanded polystyrene cushioning material was determined to be 2%:98%, with most of the stacking load applied to the product through the cushioning material.
Theory of Edge Effects and Conductance for Applications in Graphene-Based Nanoantennas
Authors: Berghaus Tomer , Miloh Touvia , Gottlieb Oded , Slepyan Gregory Ya.
Published: February 2023

In this paper, we present a theory of edge effects in graphene for its applications to nanoantennas in the THz, infrared, and visible frequency ranges. The novelty of the presented model is reflected in its self-consistency, which is reached due to the formulation in terms of dynamical conductance instead of ordinary surface conductivity. The physical model of edge effects is based on using the concept of the Dirac fermion and the Kubo approach. In contrast with earlier well-known and widely used models, the surface conductance becomes non-homogeneous and non-local. The numerical simulations of the spatial behavior of the surface conductance were performed in a wide range of values, known from the literature, for the graphene ribbon widths and electrochemical potential. It is shown that if the length exceeds 800 nm, our model agrees with the classical Drude conductivity model with a relatively high degree of accuracy. For rather short lengths, the conductance exhibits a new type of spatial oscillations, which are not present in the ordinary conductivity model. These oscillations modify the form of effective boundary conditions and integral equations for electromagnetic field at the surface of graphene-based antenna. The developed theory opens a new way for realizing electrically controlled nanoantennas by changing the electrochemical potential via gate voltage. The obtained results may be applicable for the design of different carbon-based nanodevices in modern quantum technologies.
KD-PatchMatch: A Self-Supervised Training Learning-Based PatchMatch
Authors: Tan Qingyu , Fang Zhijun , Jiang Xiaoyan
Published: February 2023

Traditional learning-based multi-view stereo (MVS) methods usually need to find the correct depth value from a large number of depth candidates, which leads to huge memory consumption and slow inference. To address these problems, we propose a probabilistic depth sampling in the learning-based PatchMatch framework, i.e., sampling a small number of depth candidates from a single-view probability distribution, which achieves the purpose of saving computational resources. Furthermore, to overcome the difficulty of obtaining ground-truth depth for outdoor large-scale scenes, we also propose a self-supervised training pipeline based on knowledge distillation, which involves self-supervised teacher training and student training based on knowledge distillation. Extensive experiments show that our approach outperforms other recent learning-based MVS methods on DTU, Tanks and Temples, and ETH3D datasets.
DIR: A Large-Scale Dialogue Rewrite Dataset for Cross-Domain Conversational Text-to-SQL
Authors: Li Jieyu , Chen Zhi , Chen Lu , Zhu Zichen , Li Hanqi , Cao Ruisheng , Yu Kai
Published: February 2023

Semantic co-reference and ellipsis always lead to information deficiency when parsing natural language utterances with SQL in a multi-turn dialogue (i.e., conversational text-to-SQL task). The methodology of dividing a dialogue understanding task into dialogue utterance rewriting and language understanding is feasible to tackle this problem. To this end, we present a two-stage framework to complete conversational text-to-SQL tasks. To construct an efficient rewriting model in the first stage, we provide a large-scale dialogue rewrite dataset (DIR), which is extended from two cross-domain conversational text-to-SQL datasets, SParC and CoSQL. The dataset contains 5908 dialogues involving 160 domains. Therefore, it not only focuses on conversational text-to-SQL tasks, but is also a valuable corpus for dialogue rewrite study. In experiments, we validate the efficiency of our annotations with a popular text-to-SQL parser, RAT-SQL. The experiment results illustrate 11.81 and 27.17 QEM accuracy improvement on SParC and CoSQL, respectively, when we eliminate the semantic incomplete representations problem by directly parsing the golden rewrite utterances. The experiment results of evaluating the performance of the two-stage frameworks using different rewrite models show that the efficiency of rewrite models is important and still needs improvement. Additionally, as a new benchmark of the dialogue rewrite task, we also report the performance results of different baselines for related studies. Our dataset will be publicly available once this paper is accepted.
A Machine Learning Tool to Monitor and Forecast Results from Testing Products in End-of-Line Systems
Authors: Nunes Carlos , Nunes Ricardo , Pires E. J. Solteiro , Barroso João , Reis Arsénio
Published: February 2023

The massive industrialization of products in a factory environment requires testing the product at a stage before its exportation to the sales market. For example, the end-of-line tests at Continental Advanced Antenna contribute to the validation of an antenna’s functionality, a product manufactured by this organization. In addition, the storage of information from the testing process allows the data manipulation through automated machine learning algorithms in search of a beneficial contribution. Studies in this area (automatic learning/machine learning) lead to the search and development of tools designed with objectives such as preventing anomalies in the production line, predictive maintenance, product quality assurance, forecast demand, forecasting safety problems, increasing resources, proactive maintenance, resource scalability, reduced production time, and anomaly detection, isolation, and correction. Once applied to the manufacturing environment, these advantages make the EOL system more productive, reliable, and less time-consuming. This way, a tool is proposed that allows the visualization and previous detection of trends associated with faults in the antenna testing system. Furthermore, it focuses on predicting failures at Continental’s EOL.
Analysis of Bone Microstructural Changes Using Raman Spectroscopy in Women with Varus Deformity of the Knee Joint in the Course of the Primary Osteoarthritis
Authors: Kasprzak Paweł , Szybowicz Mirosław , Głowacki Maciej
Published: February 2023

The aim of this study was to determine the correlation between the level of deformation, the degeneration rate of the knee joint, and the change in the structure of the subchondral bone layer affected by osteoarthritis in women. The study included patients diagnosed with primary knee osteoarthritis, with varus of the joint, planned for surgical treatment in the form of knee arthroplasty. The patients underwent a clinical and radiological assessment using standard radiographs of the knee joints in the anterior–posterior and lateral positions, while the level of varus deformity of the joint was determined on the basis of measurement radiographs of the lower limbs. Cartilage and bone materials from the tibial plateau were collected from 30 patients during the surgical treatments; these were then processed and examined using the Raman spectroscopy technique at the Department of Optical Spectroscopy of the Poznań University of Technology using the Renishaw inVia micro-Raman system coupled with a confocal microscope. The obtained Raman scattering spectra were analyzed by measuring the individual band intensities, and the results in the form of the ratios of selected Raman bands assigned to selected chemical groups were expressed as the mineralization index. The patients were divided into two groups, the first with a joint varus range of 3–10 degrees and the second with a range of 11–30 degrees. The patients were also divided into four groups, depending on the osteoarthritis degree, using the Kellgren–Lawrence scale. The investigation indicated that there is a relationship between the level of deformation and degeneration of the knee joint, expressed in scales based on radiological examination, and the coefficient, which determines the changes in the bone microstructure. The results showed that a decrease in mineralization occurred in the medial and lateral condyles as the knee osteoarthritis progressed. This study confirmed that the Raman spectroscopy technique is a useful tool for further research regarding the pathogenesis and course of osteoarthritis and may have an impact on the early diagnosis and treatment of knee osteoarthritis.
Multi-View Gait Recognition Based on a Siamese Vision Transformer
Authors: Yang Yanchen , Yun Lijun , Li Ruoyu , Cheng Feiyan , Wang Kun
Published: February 2023

Although the vision transformer has been used in gait recognition, its application in multi-view gait recognition remains limited. Different views significantly affect the accuracy with which the characteristics of gait contour are extracted and identified. To address this issue, this paper proposes a Siamese mobile vision transformer (SMViT). This model not only focuses on the local characteristics of the human gait space, but also considers the characteristics of long-distance attention associations, which can extract multi-dimensional step status characteristics. In addition, it describes how different perspectives affect the gait characteristics and generates reliable features of perspective–relationship factors. The average recognition rate of SMViT for the CASIA B dataset reached 96.4%. The experimental results show that SMViT can attain a state-of-the-art performance when compared to advanced step-recognition models, such as GaitGAN, Multi_view GAN and Posegait.
Final Setting Judgment and Safety Evaluation of Mass Concrete Based on Strain Monitoring
Authors: Xu Jie , Liu Chongyang , Lu Ziming , Ma Qian
Published: February 2023

A judgment method of the final setting time of mass concrete based on strain monitoring and the selection criterion of the starting point of effective deformation are proposed, and the safety of the concrete structure is evaluated based on this. Firstly, the strain monitoring theory of mass concrete is analyzed to clarify the temperature effect component and monitoring mechanism of an early strain of concrete. Then, taking the mass concrete plate of an engineering project as the research object combined with the mechanical analysis, the early strain monitoring data are segmented, and the relationship between the strain response and the temperature in different stages is fitted based on robust regression, so as to explore the correlation between strain and temperature in each stage and better explain the setting process of the concrete structure. Finally, taking the final setting time as the starting point of the effective strain, the safety of the concrete structure is further evaluated. The results show that there is a clear linear relationship between the strain response and temperature, and a high negative correlation between strain and temperature after the final setting. The time point when the frequency modulus corresponding to the strain enters a steady change and decreases with the increase of temperature is taken as the final setting time, which conforms to the concrete condensation mechanism and the temperature effect of early strain monitoring.
Improved Video Anomaly Detection with Dual Generators and Channel Attention
Authors: Qi Xiaosha , Hu Zesheng , Ji Genlin
Published: February 2023

Video anomaly detection is a crucial aspect of understanding surveillance videos in real-world scenarios and has been gaining attention in the computer vision community. However, a significant challenge is that the training data only include normal events, making it difficult for models to learn abnormal patterns. To address this issue, we propose a novel dual-generator generative adversarial network method that improves the model’s ability to detect unknown anomalies by learning the anomaly distribution in advance. Our approach consists of a noise generator and a reconstruction generator, where the former focuses on generating pseudo-anomaly frames and the latter aims to comprehensively learn the distribution of normal video frames. Furthermore, the integration of a second-order channel attention module enhances the learning capacity of the model. Experiments on two popular datasets demonstrate the superiority of our proposed method and show that it can effectively detect abnormal frames after learning the pseudo-anomaly distribution in advance.
CMIP6 GCM Validation Based on ECS and TCR Ranking for 21st Century Temperature Projections and Risk Assessment
Authors: Scafetta Nicola
Published: February 2023

Global climate models (GCMs) from the sixth Coupled Model Intercomparison Project Phases (CMIP6) have been employed to simulate the twenty-first-century temperatures for the risk assessment of future climate change. However, their transient climate response (TCR) ranges from 1.2 to 2.8 °C, whereas their equilibrium climate sensitivity (ECS) ranges from 1.8 to 5.7 °C, leading to large variations in the climatic impact of an anthropogenic increase in atmospheric CO2 levels. Moreover, there is growing evidence that many GCMs are running “too hot” and are hence unreliable for directing policies for future climate changes. Here, I rank 41 CMIP6 GCMs according to how successfully they hindcast the global surface warming between 1980 and 2021 using both their published ECS and TCR estimates. The sub-ensemble of GCMs with the best performance appears to be composed of the models with ECS ranging between 1.8 and 3.0 °C (which confirms previous studies) and TCR ranging between 1.2 and 1.8 °C. This GCM sub-ensemble is made up of a total of 17 models. Depending on the emission scenarios, these GCMs predict a 2045–2055 warming of 1.5–2.5 °C compared to the pre-industrial era (1850–1900). As a result, the global aggregated impact and risk estimates seem to be moderate, which implies that any negative effects of future climate change may be adequately addressed by adaptation programs. However, there are also doubts regarding the actual magnitude of global warming, which might be exaggerated because of urban heat contamination and other local non-climatic biases. A final section is dedicated to highlighting the divergences observed between the global surface temperature records and a number of alternative temperature reconstructions from lower troposphere satellite measurements, tree-ring-width chronologies, and surface temperature records based on rural stations alone. If the global warming reported by the climate records is overestimated, the real ECS and TCR may be significantly lower than what is produced by the CMIP6 GCMs, as some independent studies have already suggested, which would invalidate all of the CMIP6 GCMs.
Integrated Analysis of Lithosphere-Atmosphere-Ionospheric Coupling Associated with the 2021 Mw 7.2 Haiti Earthquake
Authors: Shahzad Faisal , Shah Munawar , Riaz Salma , Ghaffar Bushra , Ullah Irfan , Eldin Sayed M.
Published: February 2023

The search for Earthquake (EQ) precursors in the ionosphere and atmosphere from satellite data has provided significant information about the upcoming main shock. This study presents the abnormal atmospheric and ionospheric perturbations associated with the Mw 7.2 Haiti EQ on 14 August 2021 at geographical coordinates (18° N, 73° W) and shallow hypocentral depth of 10 km from the data of permanent Global Navigation Satellite System (GNSS) stations near the epicenter, followed by Swarm satellites data. The total vertical electron (VTEC) anomalies occur within a 5-day window before the main shock in the analysis of nearby operation stations, followed by Swarm (A and C satellites) ionospheric anomalies in the same 5-day window before the main shock. Moreover, the geomagnetic activities are completely quiet within 10 days before and 10 days after the main shock. Similarly, the atmospheric parameters endorse the EQ anomalies within 5 days before the main shock day. The evolution of gases from the lithosphere at the epicentral region possessed significant atmospheric and ionospheric perturbations within the EQ preparation period of 5-day before the main shock under the hypothesis of Lithosphere-Atmosphere-Ionosphere Coupling (LAIC).
Exact Expressions for Lightning Electromagnetic Fields: Application to the Rusck Field-to-Transmission Line Coupling Model
Authors: Cooray Vernon , Cooray Gerald , Rubinstein Marcos , Rachidi Farhad
Published: February 2023

An exact analytical expression for the electric field of the return stroke as excited by a propagating step current source is derived in this paper. This expression could be advantageously used to evaluate the disturbances caused by lightning on overhead lines. There are three equivalent procedures to evaluate the voltages induced by lightning on power lines, namely, the Agrawal–Price–Gurbaxani model, the Taylor–Satterwhite–Harrison model, and the Rachidi model. In the case of a vertical return stroke channel, the coupling model developed by Rusck becomes identical to these three coupling models. Due to its simplicity, the Rusck model is frequently used by engineers to study the effects of lightning on power distribution and transmission lines. In order to reduce the time involved in the electromagnetic field calculation, the Rusck model is incorporated with an analytical expression for the electromagnetic fields of the return stroke excited by a propagating step current pulse. Our research work shows that the Rusck expression can be used to calculate the peak values of lightning induced voltages to an accuracy of about 10%. However, the use of this analytical expression to calculate the time derivatives of lightning induced voltages may result in errors as large as 50%. The derived expression in this paper can be used to correct for this inaccuracy. We also provide an exact expression for the electric field at any given point in space when the propagating current is an impulse function. This expression can be combined with the convolution integral to obtain the electric field corresponding to waveforms similar to measured return stroke currents.
Estimation of Lithium-ion Battery Discharge Capacity by Integrating Optimized Explainable-AI and Stacked LSTM Model
Authors: Vakharia Vinay , Shah Milind , Nair Pranav , Borade Himanshu , Sahlot Pankaj , Wankhede Vishal
Published: February 2023

Accurate lithium-ion battery state of health evaluation is crucial for correctly operating and managing battery-based energy storage systems. Experimental determination is problematic in these applications since standard functioning is necessary. Machine learning techniques enable accurate and effective data-driven predictions in such situations. In the present paper, an optimized explainable artificial intelligence (Ex-AI) model is proposed to predict the discharge capacity of the battery. In the initial stage, three deep learning (DL) models, stacked long short-term memory networks (stacked LSTMs), gated recurrent unit (GRU) networks, and stacked recurrent neural networks (SRNNs) were developed based on the training of six input features. Ex-AI was applied to identify the relevant features and further optimize Ex-AI operating parameters, and the jellyfish metaheuristic optimization technique was considered. The results reveal that discharge capacity was better predicted when the jellyfish-Ex-AI model was applied. A very low RMSE of 0.04, MAE of 0.60, and MAPE of 0.03 were observed with the Stacked-LSTM model, demonstrating our proposed methodology’s utility.
Challenges and Future Prospects of the MXene-Based Materials for Energy Storage Applications
Authors: Nahirniak Svitlana , Ray Apurba , Saruhan Bilge
Published: February 2023

In the past decade, MXenes, a new class of advanced functional 2D nanomaterials, have emerged among numerous types of electrode materials for electrochemical energy storage devices. MXene and their composites have opened up an interesting new opportunity in the field of functional materials, owing to their transition metal nitrides/carbides/carbonitride-based unique layered structures, higher electrical and thermal conductivity, higher charge carrier mobility, high negative zeta-potential, high mechanical properties, tunable bandgap, superior hydrophilicity, metallic nature and rich surface chemistry, which enhance the number of metal active redox sites on the surface and short ion diffusion path. However, in the case of electrochemical energy storage applications, the unavoidable problem of aggregation and nanosheet restacking significantly reduces the accessibility of the active surface sites of MXene materials for electrolyte ions. Currently, there is a number of research efforts devoted to solutions in order to avoid these deficits. This Review complies extensively with the recent advances in the application of MXene-based materials in the energy storage devices such as batteries and supercapacitors. Particular attention is paid to the understanding of the relation of MXenes chemical composition, and morphology with their electrochemical performances. Moreover, the challenges of MXenes and MXene-based composited for the commercial application are considered and the ways to overcome their drawbacks are provided. Finally, opportunities given with MXenes for future research on novel energy storage materials are highlighted.
Use of Surface Electromyography to Estimate End-Point Force in Redundant Systems: Comparison between Linear Approaches
Authors: Borzelli Daniele , Gurgone Sergio , De Pasquale Paolo , Lotti Nicola , d’Avella Andrea , Gastaldi Laura
Published: February 2023

Estimation of the force exerted by muscles from their electromyographic (EMG) activity may be useful to control robotic devices. Approximating end-point forces as a linear combination of the activities of multiple muscles acting on a limb may lead to an inaccurate estimation because of the dependency between the EMG signals, i.e., multi-collinearity. This study compared the EMG-to-force mapping estimation performed with standard multiple linear regression and with three other algorithms designed to reduce different sources of the detrimental effects of multi-collinearity: Ridge Regression, which performs an L2 regularization through a penalty term; linear regression with constraints from foreknown anatomical boundaries, derived from a musculoskeletal model; linear regression of a reduced number of muscular degrees of freedom through the identification of muscle synergies. Two datasets, both collected during the exertion of submaximal isometric forces along multiple directions with the upper limb, were exploited. One included data collected across five sessions and the other during the simultaneous exertion of force and generation of different levels of co-contraction. The accuracy and consistency of the EMG-to-force mappings were assessed to determine the strengths and drawbacks of each algorithm. When applied to multiple sessions, Ridge Regression achieved higher accuracy (R2 = 0.70) but estimations based on muscle synergies were more consistent (differences between the pulling vectors of mappings extracted from different sessions: 67%). In contrast, the implementation of anatomical constraints was the best solution, both in terms of consistency (R2 = 0.64) and accuracy (74%), in the case of different co-contraction conditions. These results may be used for the selection of the mapping between EMG and force to be implemented in myoelectrically controlled robotic devices.
Cytotoxic, Elastic-Plastic and Viscoelastic Behavior of Aged, Modern Resin-Based Dental Composites
Authors: Ilie Nicoleta
Published: February 2023

The development of resin-based composites (RBCs) is a delicate balance of antagonistic properties with direct clinical implications. The clear trend toward reducing filler size in modern RBCs solves esthetic deficiencies but reduces mechanical properties due to lower filler content and increases susceptibility to degradation due to larger filler–matrix interface. We evaluated a range of nano- and nano-hybrid RBCs, along with materials attempting to address shrinkage stress issues by implementing an Ormocer matrix or pre-polymerized fillers, and materials aiming to provide caries-protective benefit by incorporating bioactive fillers. The cytotoxic response of human gingival fibroblast (HGF) cells after exposure to the RBC eluates, which were collected for up to six months, was analyzed using a WST-1 assay. The microstructural features were characterized using a scanning electron microscopy and were related to the macroscopic and microscopic mechanical behaviors. The elastic-plastic and viscoelastic material behaviors were evaluated at the macroscopic and microscopic levels. The data were supplemented with fractography, Weibull analysis, and aging behavioral analysis. The results indicate that all RBCs are non-cytotoxic at adequate exposure. The amount of inorganic filler affects the elastic modulus, while only to a limited extent the flexural strength, and is well below the theoretical estimates. The nanoparticles and the agglomeration of nanoparticles in the RBCs help generate good mechanical properties and excellent reliability, but they are more prone to deterioration with aging. The pre-polymerized fillers lower the initial mechanical properties but are less sensitive to aging. Only the Ormocer retains its damping ability after aging. The strength and modulus of elasticity on the one hand and the damping capacity on the other are mutually exclusive and indicate the direction in which the RBCs should be further developed.
A Combined in Silico and Structural Study Opens New Perspectives on Aliphatic Sulfonamides, a Still Poorly Investigated Class of CA Inhibitors
Authors: Langella Emma , Esposito Davide , Monti Simona Maria , Supuran Claudiu T. , De Simone Giuseppina , Alterio Vincenzo
Published: February 2023

Aliphatic sulfonamides are an interesting class of carbonic anhydrase inhibitors (CAIs) proven to be effective for several carbonic anhydrase (CA) isoforms involved in pathologic states. Here we report the crystallographic structures of hCA II in complex with two aliphatic sulfonamides incorporating coumarin rings, which showed a good inhibition and selectivity for this isoform. Although these two molecules have a very similar chemical structure, differing only in the substitution of the two aliphatic hydrogen atoms with two fluorine atoms, they adopt a significantly different binding mode within the enzyme active site. Theoretical binding free energy calculations, performed to rationalize these data, showed that a delicate balance of electrostatic and steric effects modulate the protein-ligand interactions. Data presented here can be fruitfully used for the rational design of novel and effective isozyme-specific inhibitor molecules.