bluuebunny/crossref_metadata_2025 huggingface dataset:
Cooperative Target Fencing Control for Unmanned Aerial Vehicle Swarm with Collision, Obstacle Avoidance, and Connectivity Maintenance
Authors: Yu Hao , Yang Xiuxia , Zhang Yi , Jiang Zijie
Published: July 2024

This paper investigates the target fencing control problem of fixed-wing Unmanned Aerial Vehicle (UAV) swarms with collision avoidance and connectivity maintenance in obstacle environments. A distributed cooperative fencing scheme for maneuvering targets is proposed without predefined accurate formation. Firstly, considering that not all states of the target can be obtained by UAVs, a differential state observer is developed to estimate the target’s unknown speed and control input. Secondly, by constructing potential functions with fewer parameter adjustments, corresponding negative gradient terms are calculated to guarantee the flight safety and communication connectivity of the swarm. A distributed cooperative controller is designed using the self-organized theory and consensus control. Additionally, the stability of the closed-loop system with the controller is analyzed based on Lyapunov stability theory. Finally, numerical simulations are performed to illustrate the effectiveness of the proposed scheme.
Attitude Control of Small Fixed−Wing UAV Based on Sliding Mode and Linear Active Disturbance Rejection Control
Authors: Wang Bohao , Yan Yuehao , Xiong Xingzhong , Han Qiang , Li Zhouguan
Published: July 2024

A combined control method integrating Linear Active Disturbance Rejection Control (LADRC) and Sliding Mode Control (SMC) is proposed to mitigate model uncertainty and external disturbances in the attitude control of fixed−wing unmanned aerial vehicles (UAVs). First, the mathematical and dynamic models of a small fixed−wing UAV are constructed. Subsequently, a Linear Extended State Observer (LESO) is designed to accurately estimate the model uncertainties and unidentified external disturbances. The LESO is then integrated into the control side to enable the SMC to enhance the control system’s anti−interference performance due to its insensitivity to variations in−system parameters. The system’s stability is proven using the Lyapunov stability theory. Finally, simulations comparing the classical LADRC and the newly developed SMC−LADRC reveal that the latter exhibits strong robustness and anti−interference capabilities in scenarios involving model uncertainty, external disturbances, and internal disturbances, confirming the effectiveness of this control method.
Natural Regeneration Patterns of Juglans mandshurica in Different Habitats
Authors: Cui Donghai , Wang Qingcheng , Ma Shuangjiao , Zhang Yong , Xu Liqing , Yan Limei
Published: July 2024

The natural regeneration of Juglans mandshurica (Juglans mandshurica Maxim.) is challenging. To elucidate its regeneration patterns, we conducted a comparative analysis of the spatial distribution and regeneration indices of Juglans mandshurica seedlings across different habitats, from the forest edge to the inner forest, over a span of 1000 m. Our findings revealed significant differences in seedling growth and regeneration patterns among these habitats. The growth indicators of Juglans mandshurica seedlings were notably higher at the forest edge compared to other habitats. The proportion of Juglans mandshurica seedlings was lower than that of 1- and 2-year-old seedlings, with only 7% being young seedlings at the forest edge. Juglans mandshurica renewal seedlings were aggregated, with the degree of aggregation as follows: 15 m > forest edge > 60 m > 30 m. The regeneration index was highest at the forest edge (1.0) and decreased with distance: 15 m (0.62), 30 m (0.52), 60 m (0.42). Shrub species and other seedlings at the forest edge showed a significant negative correlation with the Juglans mandshurica seedling numbers (p < 0.05). At 15 m, tree species displayed a significant (p < 0.05) or highly significant (p < 0.01) negative correlation. Stand closure at 30 m exhibited a substantial (p < 0.05) or highly significant (p < 0.01) negative correlation with the Juglans mandshurica regeneration index. At 60 m, the tree species, number, and basal area at breast height showed a significant (p < 0.05) or highly significant (p < 0.01) negative correlation with the Juglans mandshurica regeneration index. The forest edge had the highest renewal index and effectiveness, making it a priority for the conservation and management of Juglans mandshurica renewal. This study provides a theoretical foundation for the conservation and sustainable management of Juglans mandshurica populations.
Numerical Simulations of Scalar Transport on Rough Surfaces
Authors: Hantsis Zvi , Piomelli Ugo
Published: July 2024

Numerical simulations provide unfettered access to details of the flow where experimental measurements are difficult to obtain. This paper summarises the progress achieved in the study of passive scalars in flows over rough surfaces thanks to recent numerical simulations. Townsend’s similarity applies to various scalar statistics, implying the differences due to roughness are limited to the roughness sublayer (RSL). The scalar field exhibits a diffusive sublayer that increasingly conforms to the roughness surface as ks+ or Pr increase. The scalar wall flux is enhanced on the windward slopes of the roughness, where the analogy between momentum and scalar holds well; the momentum and scalar fields, however, have very different behaviours downwind of the roughness elements, due to recirculation, which reduces the scalar wall flux. Roughness causes breakdown of the Reynolds analogy: any increase in St is accompanied by a larger increase in cf. A flattening trend for the scalar roughness function, ΔΘ+, is observed as ks+ increases, suggesting the possibility of a scalar fully rough regime, different from the velocity one. The form-induced (FI) production of scalar fluctuations becomes dominant inside the RSL and is significantly different from the FI production of turbulent kinetic energy, resulting in notable differences between the scalar and velocity fluctuations. Several key questions remain open, in particular regarding the existence of a fully rough scalar regime and its characteristics. With the increase in Re and Pr, various quantities such as scalar roughness function, the dispersive fluxes, FI wall flux, etc., appear to trend towards saturation. However, the limited range of Re and Pr achieved by numerical simulations only allows us to speculate regarding such asymptotic behaviour. Beyond extending the range of Re and Pr, systematic coverage of different roughness types and topologies is needed, as the scalar appears to remain sensitive to the geometrical details.
Fractional Hermite–Hadamard–Mercer-Type Inequalities for Interval-Valued Convex Stochastic Processes with Center-Radius Order and Their Related Applications in Entropy and Information Theory
Authors: Shah Ahsan Fareed , Özcan Serap , Vivas-Cortez Miguel , Saleem Muhammad Shoaib , Kashuri Artion
Published: July 2024

We propose a new definition of the γ-convex stochastic processes (CSP) using center and radius (CR) order with the notion of interval valued functions (C.RI.V). By utilizing this definition and Mean-Square Fractional Integrals, we generalize fractional Hermite–Hadamard–Mercer-type inclusions for generalized C.RI.V versions of convex, tgs-convex, P-convex, exponential-type convex, Godunova–Levin convex, s-convex, Godunova–Levin s-convex, h-convex, n-polynomial convex, and fractional n-polynomial (CSP). Also, our work uses interesting examples of C.RI.V(CSP) with Python-programmed graphs to validate our findings using an extension of Mercer’s inclusions with applications related to entropy and information theory.
Auctioning off a Non-Rivalrous Good with Interference
Authors: Watts Alison
Published: July 2024

Auctions are a prevalent way to exchange goods and are well-studied for the exchange of rivalrous goods, but are less studied for non-rivalrous goods. I examine an auction framework where the good sold can be used simultaneously by multiple bidders if their use does not conflict with others; this simultaneous use directly affects the efficiency of the auction. A timely example includes the auctioning off of a radio spectrum by a licensed primary user to unlicensed secondary users who can use the spectrum simultaneously if they are located far enough apart to not cause interference. I examine a uniform price auction over non-conflicting groups and examine how non-rivalry impacts both efficiency and collusion. Conditions are given under which an auction over groups generates higher social welfare than an individual auction. Additional conditions are given under which collusion in a group auction results in higher prices.
Rolling Bearing Fault Diagnosis Based on CNN-LSTM with FFT and SVD
Authors: Xu Muzi , Yu Qianqian , Chen Shichao , Lin Jianhui
Published: July 2024

In the industrial sector, accurate fault identification is paramount for ensuring both safety and economic efficiency throughout the production process. However, due to constraints imposed by actual working conditions, the motor state features collected are often limited in number and singular in nature. Consequently, extending and extracting these features pose significant challenges in fault diagnosis. To address this issue and strike a balance between model complexity and diagnostic accuracy, this paper introduces a novel motor fault diagnostic model termed FSCL (Fourier Singular Value Decomposition combined with Long and Short-Term Memory networks). The FSCL model integrates traditional signal analysis algorithms with deep learning techniques to automate feature extraction. This hybrid approach innovatively enhances fault detection by describing, extracting, encoding, and mapping features during offline training. Empirical evaluations against various state-of-the-art techniques such as Bayesian Optimization and Extreme Gradient Boosting Tree (BOA-XGBoost), Whale Optimization Algorithm and Support Vector Machine (WOA-SVM), Short-Time Fourier Transform and Convolutional Neural Networks (STFT-CNNs), and Variational Modal Decomposition-Multi Scale Fuzzy Entropy-Probabilistic Neural Network (VMD-MFE-PNN) demonstrate the superior performance of the FSCL model. Validation using the Case Western Reserve University dataset (CWRU) confirms the efficacy of the proposed technique, achieving an impressive accuracy of 99.32%. Moreover, the model exhibits robustness against noise, maintaining an average precision of 98.88% and demonstrating recall and F1 scores ranging from 99.00% to 99.89%. Even under conditions of severe noise interference, the FSCL model consistently achieves high accuracy in recognizing the motor’s operational state. This study underscores the FSCL model as a promising approach for enhancing motor fault diagnosis in industrial settings, leveraging the synergistic benefits of traditional signal analysis and deep learning methodologies.
Compact and Low-Latency FPGA-Based Number Theoretic Transform Architecture for CRYSTALS Kyber Postquantum Cryptography Scheme
Authors: Kieu-Do-Nguyen Binh , The Binh Nguyen , Pham-Quoc Cuong , Nghi Huynh Phuc , Tran Ngoc-Thinh , Hoang Trong-Thuc , Pham Cong-Kha
Published: July 2024

In the modern era of the Internet of Things (IoT), especially with the rapid development of quantum computers, the implementation of postquantum cryptography algorithms in numerous terminals allows them to defend against potential future quantum attack threats. Lattice-based cryptography can withstand quantum computing attacks, making it a viable substitute for the currently prevalent classical public-key cryptography technique. However, the algorithm’s significant time complexity places a substantial computational burden on the already resource-limited chip in the IoT terminal. In lattice-based cryptography algorithms, the polynomial multiplication on the finite field is well known as the most time-consuming process. Therefore, investigations into efficient methods for calculating polynomial multiplication are essential for adopting these quantum-resistant lattice-based algorithms on a low-profile IoT terminal. Number theoretic transform (NTT), a variant of fast Fourier transform (FFT), is a technique widely employed to accelerate polynomial multiplication on the finite field to achieve a subquadratic time complexity. This study presents an efficient FPGA-based implementation of number theoretic transform for the CRYSTAL Kyber, a lattice-based public-key cryptography algorithm. Our hybrid design, which supports both forward and inverse NTT, is able run at high frequencies up to 417 MHz on a low-profile Artix7-XC7A100T and achieve a low latency of 1.10μs while achieving state-of-the-art hardware efficiency, consuming only 541-LUTs, 680 FFs, and four 18 Kb BRAMs. This is made possible thanks to the newly proposed multilevel pipeline butterfly unit architecture in combination with employing an effective coefficient accessing pattern.
Synthesis, Characterization, DNA, Fluorescence, Molecular Docking, and Antimicrobial Evaluation of Novel Pd(II) Complex Containing O, S Donor Schiff Base Ligand and Azole Derivative
Authors: Al-Fakeh Maged S. , Alrasheedi Muneera , Mohammed Ard Elshifa M. E. , Ibrahim Ahmed B. M. , Al-Hazmy Sadeq M. , Alhagri Ibrahim A. , Messaoudi Sabri
Published: July 2024

Pd(II) with the Schiff base ligand 2-Hydroxy-3-Methoxy Benzaldehyde-Thiosemicarbazone (HMBATSC) (L2) and 2-aminobenzothiazole (2-ABZ) (L1) was synthesized. The Schiff base ligand and the Palladium(II) complex were characterized by C.H.N.S, FT-IR, conductance studies, magnetic susceptibility, XRD, and TGA. From the elemental analysis and spectral data, the complex was proposed to have the formula [Pd(HMBATSC)(2-ABZ)H2O]. The interaction between the Pd(II) complex and DNA was examined through various methods, including UV–Vis spectroscopy, fluorescence techniques, and DNA viscosity titrations. The findings provided strong evidence that the interaction between the Pd(II) complex and DNA occurs through the intercalation mode. The analysis yielded the following values: a Stern–Volmer quenching constant (ksv) of 1.67 × 104 M−1, a quenching rate constant (kq) of 8.35 × 1011 M−1 s−1, a binding constant (kb) of 5.20 × 105 M−1, and a number of binding the sites (n) of 1.392. DFT studies suggest that the azole derivative may act as an electron donor through pyridine nitrogen, while the Schiff base ligand may act as an electron donor via oxygen and sulfur atoms. TDDFT calculations indicate that the intramolecular charge transfer from the Schiff base to Pd(II) is responsible for the complex’s fluorescence quenching. The powder X-ray diffraction data revealed that the complex is arranged in a monoclinic system. The resulting Pd(II) complex was investigated for its antimicrobial activity and demonstrated antibacterial efficiency. Interestingly, it showed potent activity against E. coli and E. niger that was found to be more powerful than that recorded for Neomycin.
The Carotenoid Composition of Larvae Feed Is Reflected in Adult House Fly (Musca domestica) Body
Authors: Lahmi Li-Or , Harari Ayelet , Shaish Aviv , Tsurim Ido
Published: July 2024

Carotenoids are common and diverse organic compounds with various functional roles in animals. Except for certain aphids, mites, and gall midges, all animals only acquire necessary carotenoids through their diet. The house fly (Musca domestica) is a cosmopolitan pest insect that populates diverse habitats. Its larvae feed on organic substrates that may vary in carotenoid composition according to their specific content. We hypothesized that the carotenoid composition in the adult house fly’s body would reflect the carotenoid composition in the larval feed. House fly larvae were reared on diets that differed in carotenoid composition. HPLC analysis of the emerging adult flies indicate that the carotenoid composition of adult house flies is related, but not identical, to the carotenoid composition in its natal substrate. These findings may be developed to help identify potential sources of house fly infestations. Also, it is recommended that rearing substrates of house fly larvae, used for animal feed, should be carefully considered.
Updating the Species Diversity of Pestalotioid Fungi: Four New Species of Neopestalotiopsis and Pestalotiopsis
Authors: Zhang Weishan , Li Yixuan , Lin Lu , Jia Aoli , Fan Xinlei
Published: July 2024

Pestalotioid fungi are associated with a wide variety of plants around the world as pathogens, endophytes, and saprobes. In this study, diseased leaves and branches of plants were collected from Guizhou and Sichuan in China. Here, the fungal isolates were identified based on a phylogenetic analysis of the internal transcribed spacer region (ITS), the translation elongation factor 1-alpha (tef1-α) and the beta-tubulin (tub2) of ribosomal DNA, and the morphological characteristics. Ten Neopestalotiopsis isolates and two Pestalotiopsis isolates were obtained, and these isolates were further confirmed as four novel species (N. acericola, N. cercidicola, N. phoenicis, and P. guiyangensis) and one known species, N. concentrica.
Layer Dependence of Complex Refractive Index in CrSBr
Authors: Hu Chao , Cheng Huanghuang , Zhou Jiayuan , Zhang Kai , Liu Xue , Jiang Yuxuan
Published: July 2024

CrSBr is a recently discovered two-dimensional anti-ferromagnet. It has attracted much attention due to its superior properties for potential optoelectronic and spintronic applications. However, its complex refractive index with layer dependence has not been systematically studied yet. In this work, we studied the room-temperature complex refractive indices of thin CrSBr flakes of different thicknesses in the visible light range. Using micro-reflectance spectroscopy, we measured the optical contrast of thin CrSBr flakes with respect to different substrates. The complex refractive index was extracted by modeling the optical contrast with the Fresnel equations. We extracted the band gap values of CrSBr in the few-layer limit. We determined the band gaps for monolayer, bilayer, and trilayer CrSBr to be 1.88 eV, 1.81 eV, and 1.77 eV, respectively. As a comparison, the band gap for multilayer CrSBr is outside our measured range, that is, below 1.55 eV. Our results suggest that the band gap of CrSBr decreases as thickness increases.
Effect of Energy Density on the Mechanical Properties of 1.2709 Maraging Steel Produced by Laser Powder Bed Fusion
Authors: Hatos István , Hargitai Hajnalka , Fekete Gusztáv , Fekete Imre
Published: July 2024

The unusual combination of the fundamentally contradictory properties of high tensile strength and high fracture toughness found in maraging steel makes it well suited for safety-critical applications that require high strength-to-weight materials. In certain instances, additive manufacturing (AM) has produced materials that may be desirable for safety-critical applications where impact toughness is a key property, such as structural parts for the aerospace industry or armor plates for military applications. Understanding the influence of process parameters and defect structure on the properties of maraging steel parts produced via laser powder bed fusion (LPBF) is a fundamental step towards the broader use of AM technologies for more demanding applications. In this research, the impact energy of V-notched specimens made of 1.2709 maraging steel produced by LPBF was determined via Charpy impact testing. Specimens were produced using different processing parameter sets. By combining the process parameters with the porosity values of the parts, we demonstrate that an almost full prediction of the impact properties can be achieved, paving the way for significantly reducing the expenses of destructive testing.
Non-Destructive Hardness Indentation Measurement of Residual Stress on Large Aerospace Forged Components at the Engineering Site Based on Impact Hardness Tester
Authors: Niu Jingyuan , Tian Peiran , Sun Siao , Zhang Yage , Song Guizeng , Song Qiang , Li Qinghua , Hu Nianxuan , Li Fuguo
Published: July 2024

Large forgings are crucial in aerospace applications; however, the residual stresses generated during their forming and heat treatment seriously affect their serviceability. Therefore, the non-destructive detection of residual stresses in large forgings is of far-reaching significance for ensuring the quality of forgings and realising precision machining. Although a variety of detection methods are available, there is still a lack of a programme that can comprehensively, accurately and non-destructively measure the residual stresses in large forgings. This study is dedicated to exploring the application of the bouncing impact indentation method in the non-destructive testing of residual stresses in large forgings. Through in-depth finite element simulations and orthogonal scheme analyses, we found that the elastic modulus, yield strength and work hardening indexes have significant effects on the impact indentation process. Further, we establish the dimensionless function of residual stress and indentation parameters, and successfully obtain the inversion algorithm of residual stress. The relative error of the calculated values of the indentation curves hm and hr in the simulation with reference values is not more than 3%, and the relative error of the corrected Pm inversion values for most virtual materials is not more than 5%. The folding elastic modulus and apparent elastic modulus obtained by inversion are controlled within 10%, which demonstrates a high value for engineering applications. In addition, we innovatively express the research results in the form of 3D stress diagrams, realising the digital expression of 3D residual stresses in large forgings based on feature point measurements and contour surface configurations, which provides intuitive and comprehensive data support for engineering practice.
First-Principles Study of the Structural, Mechanical, Electronic, and Thermodynamic Properties of AlCu2M (M = Ti, Cr, Zr, Sc, Hf, Mn, Pa, Lu, Pm) Ternary Intermetallic Compounds
Authors: Guo Yu , Jiang Bo , Zhang Xun , Li Shikang
Published: July 2024

Based on the first principles, the structural stability, mechanical characteristics, electronic structure, and thermodynamic properties of AlCu2M (M = Ti, Cr, Zr, Sc, Hf, Mn, Pa, Lu, Pm) are investigated. The calculated results indicate that the AlCu2Pa crystal structure is more stable and that AlCu2Pa should be easier to form. All of the AlCu2M compounds have structural stability in the ground state. Elastic constants are used to characterize the mechanical stability and elastic modulus, while the B/G values and Poisson ratio demonstrate the brittleness and ductility of AlCu2M compounds. It is demonstrated that all computed AlCu2M compounds are ductile and mechanically stable, with AlCu2Hf having the highest bulk modulus and AlCu2Mn having the highest Young’s modulus. AlCu2Mn has the highest intrinsic hardness among AlCu2M compounds, according to calculations of their intrinsic hardness. The electronic densities of states are discussed in detail; it was discovered that all AlCu2M compounds form Al-Cu and Al-M covalent bonds. Additionally, we observe that the Debye temperature and minimum thermal conductivity of AlCu2Mn and AlCu2Sc are both larger than those of others, indicating stronger chemical bonds and higher thermal conductivities, which is consistent with the elastic modulus results.
Performance and Environmental Assessment of Biochar-Based Membranes Synthesized from Traditional and Eco-Friendly Solvents
Authors: Fionah Abelline , Oluk Isaac , Brady Laura , Byrne Diana M. , Escobar Isabel C.
Published: July 2024

Water contamination resulting from coal spills is one of the largest environmental problems affecting communities in the Appalachia Region of the United States. This coal slurry contains potentially toxic substances, such as hydrocarbons, heavy metals, and coal cleaning chemicals, and its leakage into water bodies (lakes, rivers, and aquifers) can lead to adverse health effects not only for freshwater bodies and plant life but also for humans. This study focused on two major experiments. The first experiment involved the use of biochar to create a biochar–polysulfone (BC-PSf) flat-sheet multifunctional membrane to remove organic contaminants, and the other major experiment compared eco-friendly (gamma-valerolactone—GVL; Rhodiasolv® PolarClean—PC) and petroleum-derived solvents (i.e., N-methyl-pyrrolidone—NMP) in the fabrication of the biochar–polysulfone membranes. The resulting membranes were tested for their efficiency in removing both positively and negatively charged organic contaminants from the collected water at varying pH values. A comparative life cycle assessment (LCA) with accompanying uncertainty and sensitivity analyses was carried out to understand the global environmental impacts of incorporating biochar, NMP, GVL, and PC in the synthesis of PSf/NMP, BC-PSf/NMP, PSf/GVL, BC-PSf/GVL, PSf/PC, and BC-PSf/PC membranes at a set surface area of 1000 m2. The results showed that the addition of biochar to the membrane matrix increased the surface area of the membranes and improved both their adsorptive and mechanical properties. The membranes with biochar incorporated in their matrix showed a higher potential for contaminant removal than those without biochar. The environmental impacts normalized to the BC-PSf/GVL membrane showed that the addition of biochar increased global warming impacts, eutrophication, and respiratory impacts by over 100% in all the membrane configurations with biochar. The environmental impacts were highly sensitive to biochar addition (Spearman’s coefficient > 0.8). The BC/PSf membrane with Rhodiasolv® PolarClean had the lowest associated global environmental impacts among all the membranes with biochar. Ultimately, this study highlighted potential tradeoffs between functional performance and global environmental impacts regarding choices for membrane fabrication.
Optimization of Extraction and Purification of Flavonoids from Stigmaless Floral Residues of Crocus sativus L. and Their Stimulatory Effect on Glucose Uptake In Vitro
Authors: Chen Sunce , Lv Quanhe , Liu Chunhui , Yuan Hongxia , Li Chunfei , Liu Yifan , Zhang Wen
Published: July 2024

Saffron, the dried stigma of Crocus sativus L., is a renowned spice and medicinal herb. During its production, a significant amount of floral residues, rich in bioactive compounds, are discarded as agricultural by-products. This study presents a novel approach to the sustainable utilization of these stigmaless floral residues (FRC) by optimizing the extraction and purification of their flavonoids, analyzing their chemical composition, and evaluating their effect on glucose uptake. The extraction of flavonoids from FRC was optimized using single-factor experiments and response surface methodology. The optimal conditions for extraction were an ethanol concentration of 67.7%, a temperature of 67.6 °C, a solid-to-liquid ratio of 1:30, an extraction time of 3 h, and two extractions. The crude extract obtained was then purified using macroporous resin HPD100, selected after comparing the adsorption and desorption characteristics of six different resins. The optimal purification parameters were an adsorption concentration of 40 mg/mL, a loading volume of 7 bed volumes (BV) at a flow rate of 3 BV/h, and 80% ethanol as the eluent with a volume of 4 BV. The resulting flavonoid-enriched extract (FFRC) had an experimental yield of 8.67% ± 0.01 and a flavonoid content of 128.30 ± 4.64 mg/g. The main flavonoids in FFRC were identified as kaempferol glycosides, isorhamnetin glycosides, and quercetin glycosides. Moreover, FFRC significantly stimulated glucose consumption and uptake in C2C12 myotubes, suggesting its potential utility as a natural hypoglycemic agent. This study contributes to the sustainable and value-added utilization of agricultural resources by providing data for the exploitation and application of flavonoids from saffron by-products.
Impact of Different Carbon Sources on Volatile Organic Compounds (VOCs) Produced during Fermentation by Levilactobacillus brevis WLP672 Measured Using Proton Transfer Reaction Time-of-Flight Mass Spectrometry (PTR-ToF-MS)
Authors: Rajendran Sarathadevi , Khomenko Iuliia , Silcock Patrick , Betta Emanuela , Biasioli Franco , Bremer Phil
Published: July 2024

Bacterial fermentation is considered to be a cost-effective means of generating desired flavour compounds from plant-based substrates. However, the wide range of substrates present in plants makes it challenging to understand how individual components impact on flavour volatile organic compound (VOC) production. To simplify this, a defined medium can be used to better understand VOCs production with regard to individual compounds. In the current study, the VOCs produced by the lactic acid bacterium, Levilactobacillus brevis WLP672, growing in a defined medium containing different carbon sources (either glucose (DM), fructose (DMFr) or citrate (DMCi)) under a range of fermentation conditions (time: 0, 7, and 14 days; and temperature: 25 and 35 °C) were assessed using proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS). Among the detected mass peaks (m/z), after 7 days of fermentation, the concentrations of m/z 45.033 (t.i. acetaldehyde), m/z 49.011 (t.i. methanethiol), and m/z 89.060 (t.i. ethyl acetate) were significantly (p < 0.05) higher in DM at 35 °C than all other treatments at either temperature. The knowledge obtained will help to produce desirable LAB fermentation flavour VOCs or VOC mixtures that could be used in developing plant-based analogues with acceptable sensory properties.
Study of Ammonia Adsorption on Magnetite Surfaces with Molecular Dynamics Simulations
Authors: Ivanova Nikoleta , Karastoyanov Vasil , Betova Iva , Bojinov Martin
Published: July 2024

The present study proposes an atomistic molecular dynamics model system of a magnetite (Fe3O4) {111} surface. The effect of temperature on the adsorption process of ammonia (NH3) at low concentrations in the aqueous phase has been considered. The molecular dynamics simulations were carried out using the Clay force field (Clay FF) with a modification for the iron atoms in the NPT ensemble at a pressure of 90 bar. The considered system was heated in a temperature range from 293 to 473 K, and additional relaxations were performed at temperatures of interest. Within the scope of this study, the basic parameters of the magnetite surface were calculated and the distances between the ammonia molecules and the surface were determined. A general idea of the degree and rate of adsorption at specific temperatures was obtained. The calculation results were compared to the experimental data where possible and to other available simulations of adsorption processes on metal oxides.
Obtaining Cellulose Fibers from Almond Shell by Combining Subcritical Water Extraction and Bleaching with Hydrogen Peroxide
Authors: Gil-Guillén Irene , Freitas Pedro A. V. , González-Martínez Chelo , Chiralt Amparo
Published: July 2024

Almond shell (AS) represents about 33% of the almond fruit, being a cellulose-rich by-product. The use of greener methods for separating cellulose would contribute to better exploitation of this biomass. Subcritical water extraction (SWE) at 160 and 180 °C has been used as a previous treatment to purify cellulose of AS, followed by a bleaching step with hydrogen peroxide (8%) at pH 12. For comparison purposes, bleaching with sodium chlorite of the extraction residues was also studied. The highest extraction temperature promoted the removal of hemicellulose and the subsequent delignification during the bleaching step. After bleaching with hydrogen peroxide, the AS particles had a cellulose content of 71 and 78%, with crystallinity index of 50 and 62%, respectively, for those treated at 160 and 180 °C. The use of sodium chlorite as bleaching agent improved the cellulose purification and crystallinity index. Nevertheless, cellulose obtained by both bleaching treatments could be useful for different applications. Therefore, SWE represents a promising green technique to improve the bleaching sensitivity of lignocellulosic residues, such as AS, allowing for a great reduction in chemicals in the cellulose purification processes.
Personalized Nutrition Therapy without Weight Loss Counseling Produces Weight Loss in Individuals with Prediabetes Who Are Overweight/Obese: A Randomized Controlled Trial
Authors: Basiri Raedeh , Cheskin Lawrence J.
Published: July 2024

Obesity stands out as a primary risk factor for diabetes. Attaining healthy weight loss, especially reducing body fat, is important in managing prediabetes and preventing progression to full diabetes and its co-morbidities. This study examined the effects of personalized nutrition therapy (PNT) combined with continuous glucose monitoring (CGM) on body weight and composition in individuals with prediabetes. A total of 30 individuals with prediabetes who were overweight or obese were assigned randomly to either the treatment, observed CGM data plus PNT, or the control group which was blinded to their blood glucose results throughout the study. Both groups were provided with dietary recommendations for calorie intake and macronutrient distribution, coupled with personalized goal setting for glucose control and healthy eating, without any specific emphasis on weight reduction or changes in physical activity. Regular visits were scheduled every 10 days to perform measurements and replace CGMs. Data were analyzed using General Linear Model with repeated measures. Over the 30-day follow-up period, both groups experienced significant reductions in weight and fat mass. The treatment group exhibited two-fold greater reductions in both weight and fat mass, a significant decrease in carbohydrate intake, and a significant increase in time spent on physical activitycompared to the control group. In addition, compliance was notably higher in the treatment group. These findings indicate that overweight or obese individuals with prediabetes can achieve weight loss and improved body composition through personalized education for glucose control, without exclusively emphasizing weight loss as the primary objective. Additionally, the real-time feedback provided by CGM enhances these improvements.
Planetary Health Diet Compared to Dutch Dietary Guidelines: Nutritional Content and Adequacy
Authors: Uriza-Pinzón Julieth Pilar , Verstraete Femke Fleur , Franco Oscar H. , Artola Arita Vicente , Nicolaou Mary , Van der Schouw Yvonne T.
Published: July 2024

In 2019, the EAT-Lancet Commission proposed a Planetary Health Diet (PHD) to address challenges toward sustainable and healthy diets. However, its suitability within the Dutch context and a comparison with the Dutch Dietary Guidelines (DDG) needs investigation. Our study aimed to compare the PHD with DDG in terms of food groups, servings, nutritional content, and adequacy in adults. We modeled two theoretical diets, the PHD (PHD-NL) and another based on the DDG (DDG-NL), using the Dutch National Food Consumption Survey (FCS-2016) and Dutch Food Composition Database to calculate the nutritional content and compared it with the Dutch Dietary Reference Values (DRVs). The PHD included higher quantities of vegetables, fish, legumes, and nuts, while the DDG suggested more significant amounts of cereals, tubers, starchy vegetables, dairy, and red meat. We observed differences in macronutrient distribution; while both diets lacked sufficient vitamin D, calcium content was lower in the PHD-NL. The PHD-NL had higher levels of fiber, vegetable protein, unsaturated fats, and non-heme iron, while vitamins B2, B6, B12, and calcium were lower than the DDG-NL diet. The PHD-NL has nutritional adequacy in the Dutch context, except for vitamin D and calcium, although it is essential to be cautious with iron because of the bioavailability of non-heme iron in plant-based diets. These findings have implications for the adoption of a sustainable diet according to nutritional requirements, population health status, and sociocultural context, as well as compliance with specific dietary behaviors of populations.
Effects of Different Caffeine Dosages on Maximal Physical Performance and Potential Side Effects in Low-Consumer Female Athletes: Morning vs. Evening Administration
Authors: Bougrine Houda , Ammar Achraf , Salem Atef , Trabelsi Khaled , Żmijewski Piotr , Jahrami Haitham , Chtourou Hamdi , Souissi Nizar
Published: July 2024

While previous studies have explored a range of factors governing the optimal use of caffeine (CAF) in athletes, limited research has explored how time of day (TOD) affects the ergogenic effects of various CAF dosages on physical performance. This study aimed to increase knowledge about how different recommended CAF doses (3 mg/kg vs. 6 mg/kg) ingested at different TODs affected maximal high-intensity physical performance and the perception of potential side effects in female athletes. In this double-blind, randomized, and counterbalanced study, 15 low CAF consumer athletes (aged 18.3 ± 0.5 y) underwent six trials, including three testing conditions assessed across two TODs: one in the morning (08:00 a.m.) and one in the evening (06:00 p.m.). During each condition, the participants ingested either a placebo, 3 mg/kg CAF (CAF (3 mg)), or 6 mg/kg CAF (CAF (6 mg)) capsules 60 min before each test with an in-between washout period of at least 72 h. In each trial, the participants performed a countermovement jumps test (CMJ), a modified agility t test (MATT), a repeated sprint ability (RSA), a rating of perceived exertion (RPE), and finally, a CAF side effects questionnaire. Our findings indicate the absence of an ergogenic effect on CMJ, MAT, and RSA performance in the evening after administering CAF (3 mg) or CAF (6 mg) compared to a placebo. Likewise, when CAF was ingested in the morning, there was an improvement in these performances with both CAF (3 mg) and CAF (6 mg), with greater improvement observed after CAF (6 mg). Additionally, neither the CAF dosage nor the TOD had a significant effect on the RPE. The occurrence of side effects increased significantly after the evening ingestion of CAF, particularly with a moderate dose of CAF (6 mg). Our findings indicate that the effectiveness of CAF depends on the TOD and CAF dosage. When ingested in the morning, a moderate dose of CAF (6 mg), rather than CAF (3 mg), is more effective in improving short-term physical performance without affecting CAF side effects in female athletes. Nevertheless, when ingested in the evening, neither dose was sufficient to enhance short-term physical performance, and both dosages increased the incidence of CAF side effects, particularly at a moderate dose.
Efficacy of Dietary Therapy for Eosinophilic Esophagitis in Children and Adults: An Updated Systematic Review and Meta-Analysis
Authors: Arias Ángel , Tejera-Muñoz Antonio , Gutiérrez-Ramírez Lucía , Molina-Infante Javier , Lucendo Alfredo J.
Published: July 2024

Background: Several dietary approaches have been used to induce remission in patients with eosinophilic esophagitis (EoE), yielding varied results. Methods: We searched the MEDLINE, EMBASE, and Scopus databases up to May 2024 to identify studies including dietary interventions for EoE used as monotherapy. Summary estimates with 95% CIs for achieving <15 eosinophils/HPF were calculated for each approach. Fixed or random effects models were used depending on heterogeneity (I2); publication bias risks were assessed using funnel plot analyses. Subgroup analyses results were compared using meta-regression. Results: Forty-three studies with 2825 patients were included in quantitative summaries. The overall rate of histologic remission was 60.6% (95% CI, 54.6–66.5%). Effectiveness rates were 94.5% (95% CI, 92.3–96.4%) for elemental diets, 63.9% (95% CI, 58.5–69.2%) for six-food elimination diets, 54.7% (95% CI, 45.7–63.6%) for four-food elimination diets, 44.3% (95% CI, 36.1–52.8%) for two-food elimination diets, 46.4% (95% CI, 40–52.9%) for one-food elimination diets, and 39.5% (95% CI, 30.3–49.2%) for allergy testing-directed food elimination diets. Overall, superior efficacy was noted in children than in adults and in retrospective compared to prospective studies. Conclusion: Diet therapy remains an effective therapeutic asset for pediatric and adult patients with EoE, with increasing efficacy noted as the levels of dietary restriction increase.
Supplementation of Vitamin D3 and Fructooligosaccharides Downregulates Intestinal Defensins and Reduces the Species Abundance of Romboutsia ilealis in C57BL/6J Mice
Authors: Hanson Tyler , Constantine Ethan , Nobles Zack , Butler Emily , Renteria Karisa M. , Teoh Chin May , Koh Gar Yee
Published: July 2024

The activation of the vitamin D receptor (VDR) in the ileum has been shown to regulate Paneth cell-specific defensins, a large family of antimicrobial peptides; hence, this may serve as a potential mechanism to maintain intestinal homeostasis. Previously, we have demonstrated that a combination of vitamin D3 (VD) and fructooligosaccharides (FOSs) upregulates colonic Vdr in mice. Here, we aim to examine the effect of VD, alone or in combination with FOSs, on intestinal barrier integrity and the secretion of antimicrobial peptides, as well as the gut microbial community. Male and female C57BL/6J mice at 6 weeks old were randomized into three groups to receive the following dietary regimens (n = 10/sex/group) for 8 weeks: (1) standard AIN-93G control diet (CTR), (2) CTR + 5000 IU vitamin D3 (VD), and (3) VD + 5% fructooligosaccharides (VF). VD and VF differentially regulated the mRNA expressions of tight junction proteins in the colon and ileum. VF suppressed the upregulation of colonic ZO-1 and occludin, which was induced by VD supplementation alone. In the ileum, occludin but not ZO-1 was upregulated 20-fold in the VF-treated mice. While VD did not alter the mRNA expressions of Vdr and defensins in the ileum, these targets were downregulated by VF. Microbial analysis further reveals a shift of microbial beta diversity and a reduction in Romboutsia ilealis, a pathobiont, in VF-treated mice. Though the implications of these phenotypical and microbial changes remain to be determined, the administration of FOSs in the presence of VD may serve as an effective dietary intervention for maintaining intestinal homeostasis.
Association between Coffee Consumption and Polycystic Ovary Syndrome: An Exploratory Case–Control Study
Authors: Meliani-Rodríguez Aïcha , Cutillas-Tolín Ana , Mendiola Jaime , Sánchez-Ferrer María Luisa , De la Cruz-Sánchez Ernesto , Vioque Jesús , Torres-Cantero Alberto M.
Published: July 2024

Polycystic ovary syndrome (PCOS) is a leading cause of infertility, with an estimated worldwide prevalence between 5% and 15%. We conducted a case–control study with 121 PCOS patients and 155 controls to assess the association between coffee intake and the presence of having a diagnosis of PCOS in women in Murcia, Spain. The PCOS diagnosis was determined following Rotterdam criteria (the presence of two of the following three conditions: hyperandrogenism, oligo-anovulation, and/or polycystic ovarian morphology). Coffee consumption was assessed using a validated food frequency questionnaire. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using multiple logistic regression. Coffee consumption was categorized into never, less than one cup per day, one cup per day, and two or more cups per day. We found a significant inverse linear trend: the higher the coffee consumption, the lower the probability of having PCOS in multivariable analysis (p-trend = 0.034). Women who presented with PCOS were less likely to drink one cup of coffee compared to those who had never drunk coffee (OR = 0.313, 95% CI: 0.141–0.69). The consumption of at least one cup of coffee per day may be associated with a decrease in PCOS symptoms.
Three-Dimensional Exploding Light Wave Packets
Authors: Barriopedro Marcos G. , Holguín Manuel , de Lara-Montoya Pablo , Mata-Cervera Nilo , Porras Miguel A.
Published: July 2024

We describe a family of paraxial and quasi-monochromatic optical wave packets with finite energy and smoothly shaped amplitude in space and time that develops a singularity in the intensity when spatio-temporally focused by imparting a converging spherical wavefront and a negative temporal chirp. This singular behavior upon ideal focusing is manifested in actual focusing with finite apertures and in media with high-order dispersion with “exploding” behavior featuring an indefinitely increasing concentration of the energy when opening the aperture radius, thus exercising continuous control on the focal intensity and spatial and temporal resolution. These wave packets offer a new way of focusing that outperforms what can be achieved with standard Gaussian wave packets in terms of focal intensity and resolution, providing new possibilities in applications where energy concentration and its control are crucial.
Durable, Photostable Omniphobic Synthetic Leather Surfaces with Anti-Biofouling Properties for Hygienic Applications
Authors: Lee Hanna , Oh Jun Kyun
Published: July 2024

Globally, the public health domain is increasingly emphasizing the need for surfaces that can resist bacterial contamination, as the consumption of bacteria-infected substance may cause illnesses. Thus, this study aimed to modify polyurethane (PU) synthetic leather surfaces by coating their upper layer with fluorine-functionalized nano-silica particles (FNPs). This simple modification imparted omniphobic characteristics, realizing anti-biofouling and self-cleaning properties. The effectiveness in preventing bacterial adhesion was confirmed by the dip-inoculation method using Escherichia coli O157:H7 and Staphylococcus epidermidis. Bacterial adhesion was evaluated based on bacterial counts using the pour plate method and by directly enumerating from scanning electron microscopy images. The attachment of bacteria to the modified omniphobic FNPs-coated PU leather surface decreased by over 98.2% compared to that on the bare surface. We expect that the method developed in this study will significantly reduce or even eliminate the potential risks associated with various biological cross-contamination scenarios, thereby enhancing hygiene standards.
Study the Global Earthquake Patterns That Follow the St. Patrick’s Day Geomagnetic Storms of 2013 and 2015
Authors: Ouzounov Dimitar , Khachikyan Galina
Published: July 2024

A response of global seismic activity to the geomagnetic storms of St. Patrick’s Day (March 17) in 2013 and 2015 is investigated. These two storms occurred during nearly identical storm sudden commencement times and similar solar flux levels. We have revealed a rather similar pattern of the most substantial earthquakes that have occurred since these storms. Two major crust continental earthquakes, in Iran (M = 7.7), 16 April 2013, and in Nepal (M = 7.8), 25 April 2015, have occurred with a time delay of ~30 and ~39 days after geomagnetic storm onsets in 2013 and 2015, respectively. After that, the great and major deep-focused earthquakes occurred beneath the Sea of Okhotsk (M = 8.3, 24 May 2013, Russia) and the Pacific Ocean (M = 7.8, 30 May 2015, Japan) with a time delay of ~68 and ~74 days, respectively. Geomagnetic storm onsets occurred at 06:04 UT in 2013 and 04:48 UT in 2015. At this time, the high latitudinal areas of the longitudinal regions, in which the mentioned earthquakes occurred in the future, were located under the polar cusp, where the solar wind plasma has direct access to the Earth’s environment. An analysis of the remaining ten earthquakes with M ≥ 7.5, which occurred around the globe in 2013 and 2015, proved the above findings that seismic activity may respond to geomagnetic storm onset with a time delay from some days to some months.