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On a Generic Fractional Derivative Associated with the Riemann–Liouville Fractional Integral
Animals
Native Compared to Citrated Whole Blood for Coagulation Testing in Horses
Nutrients
Egg Consumption and 4-Year Change in Cognitive Function in Older Men and Women
Sustainability
Can the UK Deliver Zero Carbon Ready Homes by 2050?
Geosciences
Stealth Metasomatism in Granulites from Ivrea (NW Italy): Hydration of the (Variscan) Lower Crust by Melt Flow

Recent Articles

23 pages, 10915 KiB

Open AccessArticle

10 MW FOWT Semi-Submersible Multi-Objective Optimization: A Comparative Study of PSO, SA, and ACO

by Souleymane Drabo, Siqi Lai, Hongwei Liu and Xiangheng Feng

Energies 2024, 17(23), 5914; https://doi.org/10.3390/en17235914 (registering DOI) - 25 Nov 2024

The present study aims to carry out a comparative Multi-Objective Optimization (MOO) of a 10 MW FOWT semi-submersible using three different metaheuristic optimization techniques and a sophisticated approach for optimizing a floating platform. This novel framework enables highly efficient 3D plots, an optimization loop, and the automatic and comparative output of solutions. Python, the main interface, integrated PyMAPDL and Pymoo for intricate modeling and simulation tasks. For this case study, the ZJUS10 Floating Offshore Wind Turbine (FOWT) platform, developed by the state key laboratory of mechatronics and fluid power at Zhejiang University, was employed as the basis. Key criteria such as platform stability, overall structural mass, and stress were pivotal in formulating the objective functions. Based on a preliminary study, the three metaheuristic optimization algorithms chosen for optimization were Particle Swarm Optimization (PSO), Simulated Annealing (SA), and Ant Colony Optimization (ACO). Then, the solutions were evaluated based on Pareto dominance, leading to a Pareto front, a curve that represents the best possible trade-offs among the objectives. Each algorithm’s convergence was meticulously evaluated, leading to the selection of the optimal design solution. The results evaluated in simulations elucidate the strengths and limitations of each optimization method, providing valuable insights into their efficacy for complex engineering design challenges. In the post-processing phase, the performances of the optimized FOWT platforms were thoroughly compared both among themselves and with the original model, resulting in validation. Finally, the ACO algorithm delivered a highly effective solution within the framework, achieving reductions of 19.8% in weight, 40.1% in pitch, and 12.7% in stress relative to the original model. Full article

(This article belongs to the Section K: State-of-the-Art Energy Related Technologies)

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20 pages, 1620 KiB

Open AccessArticle

Contextual Attribution Maps-Guided Transferable Adversarial Attack for 3D Object Detection

by Mumuxin Cai, Xupeng Wang, Ferdous Sohel and Hang Lei

Remote Sens. 2024, 16(23), 4409; https://doi.org/10.3390/rs16234409 (registering DOI) - 25 Nov 2024

Abstract

The study of LiDAR-based 3D object detection and its robustness under adversarial attacks has achieved great progress. However, existing adversarial attack methods mainly focus on the targeted object, which destroys the integrity of the object and makes the attack easy to perceive. In this work, we propose a novel adversarial attack against deep 3D object detection models named the contextual attribution maps-guided attack (CAMGA). Based on the combinations of subregions in the context area and their impact on the prediction results, contextual attribution maps can be generated. An attribution map exposes the influence of individual subregions in the context area on the detection results and narrows down the scope of the adversarial attack. Subsequently, perturbations are generated under the guidance of a dual loss, which is proposed to suppress the detection results and maintain visual imperception simultaneously. The experimental results proved that the CAMGA method achieved an attack success rate of over 68% on three large-scale datasets and 83% on the KITTI dataset. Meanwhile, the CAMGA has a transfer attack success rate of at least 50% against all four victim detectors, as they all overly rely on contextual information. Full article

(This article belongs to the Special Issue Artificial Intelligence-Based Sensor Data Processing for Remote Sensing)

17 pages, 354 KiB

Open AccessArticle

Servant Leadership and Teachers’ Emotional Exhaustion—The Mediation Role of Hindrance Stress and Depersonalization

by Hongchao Wu, Jun Zhao, Shaoping Qiu and Xiuhong Li

Behav. Sci. 2024, 14(12), 1129; https://doi.org/10.3390/bs14121129 (registering DOI) - 25 Nov 2024

Abstract

This study aims to explore the impact of school servant leadership on teacher emotional exhaustion in the context of Chinese education, and analyze the mediating effects of teacher hindrance stress and depersonalization. Based on the Job Demand-Control-Support (JDCS) model and servant leadership theory, the research constructs a model for the influence mechanism of school servant leadership on teacher emotional exhaustion and validates it using Structural Equation Modeling (SEM). A total of 3751 primary and secondary school teachers from eight provinces in China participated in this study. The results indicate servant leadership demonstrates a strong negative relationship with emotional exhaustion, with hindrance stress and depersonalization serving as a sequential mediation between servant leadership and emotional exhaustion. This study offers a new perspective on how servant leadership can alleviate emotional exhaustion among teachers, and provides practical insights for optimizing educational management models and enhancing teacher mental well-being. Full article

28 pages, 4811 KiB

Open AccessReview

From Mine Waste to Construction Materials: A Bibliometric Analysis of Mining Waste Recovery and Tailing Utilization in Construction

by Vicente Zetola, Brian F. Keith, Elizabeth J. Lam, Ítalo L. Montofré, Rodrigo J. Rojas, Juan Marín and Mathias Becerra

Sustainability 2024, 16(23), 10314; https://doi.org/10.3390/su162310314 (registering DOI) - 25 Nov 2024

Abstract

This article presents a comprehensive scientometric analysis of mining waste valorization, focusing on tailings utilization in construction materials from 2010 to 2024. Through examination of 1096 Web of Science publications and utilizing CiteSpace mapping and network analyses, we analyze the intellectual structure of this field. Subject category analysis reveals materials science, construction technology, and environmental engineering as the dominant disciplines, interconnected through 168 links across 64 thematic nodes. Our co-citation analysis identifies 12 major research clusters, with materials science and environmental engineering serving as primary disciplinary pillars. Keyword co-occurrence analysis of 532 nodes connected by 1181 links highlights the field’s emphasis on fly ash, concrete applications, and mechanical properties. Recent citation bursts indicate growing research focus on thermal stability, heavy metal treatment, and innovative processing methods. Through synthesizing these scientometric indicators, this review provides strategic insights for advancing sustainable construction practices through mining waste utilization. Research gaps identified include long-term durability assessment, standardization needs, and scalability challenges. By synthesizing these diverse scientometric indicators, this review provides strategic insights for researchers, industry practitioners, and policymakers, contributing to the advancement of sustainable construction practices through mining waste utilization. Full article

(This article belongs to the Section Waste and Recycling)

21 pages, 6247 KiB

Open AccessArticle

Analysis of the Existing Air Emissions Detection Methods for Stationary Pollution Sources Monitoring

by Alexandr Neftissov, Andrii Biloshchytskyi, Ilyas Kazambayev, Lalita Kirichenko, Ultuar Zhalmagambetova and Svitlana Biloshchytska

Appl. Sci. 2024, 14(23), 10934; https://doi.org/10.3390/app142310934 (registering DOI) - 25 Nov 2024

Abstract

The application of coal technologies for energy generation leads to high pollutant emissions. Thus, governmental and international organizations have created new programs and laws for monitoring emissions. Recently, the government of Kazakhstan has introduced regulations for the measurement of emissions produced by factories and power plants. However, the requirements and Corecommendations for the monitoring methods have not been defined. Therefore, this article addresses the problem and focuses on determining the measurement errors made by optical SGK510 and electrochemical POLAR devices used for coal power plants. The hypothesis is based on the fact that there are currently no systems for monitoring probe drying, and its implementation is expensive. The main methods are analyzed, namely their operation, taking into account the presence of water particles in samples, and the possibility of using adjustment coefficients is considered. The main pollutants chosen for analysis are CO, NO, NO₂, NO_x, SO₂, and O₂. Using the Broich–Pagan test, homoscedasticity was determined, and the Fisher test showed the possibility of using tuning coefficients. The data for the optical method were compared to measurements taken using Inspector 500. The error for SO₂ determination was 7.19% for NO, 44.0985% for NO₂, 733.26% for NO_x, 7.39% for O₂, 2.75% for CO, 60.81%. The comparison between SGK510 and POLAR demonstrated the following errors: for CO—1.5%, for NO_x—82.4405%, for SO₂—41.17%, for O₂—11.61%. According to the Fisher criteria analysis of the optical method, only SO₂ and CO values measured by SGK510 in comparison to Inspector 500 had close similarity, while others demonstrated high deviations. The significance tests were carried out by Fisher’s, t-test, and ANOVA methods. For the electrochemical measurement, only CO values had close similarity. In the future, methods will be proposed to improve the accuracy of the system while reducing maintenance costs, as well as cleaning sampling systems. The multicomponent analysis application for accuracy improvement with the exhaust gas humidity, temperature, and flow consideration was recommended as a possible solution. Full article

(This article belongs to the Section Ecology Science and Engineering)

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31 pages, 1834 KiB

Open AccessReview

The Use of Calcium Phosphate Bioceramics for the Treatment of Osteomyelitis

by Cláudia Suellen Ferro Oliveira, Irina Negut and Bogdan Bita

Ceramics 2024, 7(4), 1779-1809; https://doi.org/10.3390/ceramics7040113 (registering DOI) - 25 Nov 2024

Abstract

Bone infections, particularly osteomyelitis, present significant clinical challenges due to their resistance to treatment and risk of progressing to chronic disease. Conventional therapies, including systemic antibiotics and surgical debridement, often prove insufficient, especially in cases where biofilms form or infection sites are difficult to access. As an alternative, calcium phosphate bioceramics have emerged as a promising strategy for treating bone infections. These materials offer key advantages such as biocompatibility, osteoconductivity, and the ability to be engineered for controlled drug delivery. Calcium phosphate bioceramics can serve as scaffolds for bone regeneration while simultaneously delivering antibiotics locally, thus addressing the limitations of systemic therapies and reducing infection recurrence. This review provides an overview of osteomyelitis, including its pathogenesis and conventional treatment approaches, while exploring the diverse therapeutic possibilities presented by calcium phosphate bioceramics. Special attention is given to hydroxyapatite, tricalcium phosphate, and their composites, with a focus on their therapeutic potential in the treatment of bone infections. The discussion highlights their mechanisms of action, integration with antimicrobial agents, and clinical efficacy. The dual capacity of calcium phosphate bioceramics to promote both bone healing and infection management is critically evaluated, highlighting opportunities for future research to address current challenges and enhance their clinical application in orthopedics and dentistry. Future research directions should focus on developing calcium phosphate bioceramic composites with enhanced antibacterial properties, optimizing drug-loading capacities, and advancing minimally invasive delivery methods to improve clinical outcomes. Further in vivo studies are essential to validate the long-term efficacy and safety of calcium phosphate bioceramic applications, with an emphasis on patient-specific formulations and rapid prototyping technologies that can personalize treatment for diverse osteomyelitis cases. Full article

(This article belongs to the Special Issue Advances in Ceramics, 2nd Edition)

13 pages, 471 KiB

Open AccessArticle

Enhancing Mycotoxin Detection in Table Olives: The Role of Enzyme-Linked Immunosorbent Assay and Method Optimization

by Alessandro Cammerata, Viviana Del Frate, Tiziana Monforte, Antonio Scarfone and Elio Romano

Appl. Sci. 2024, 14(23), 10936; https://doi.org/10.3390/app142310936 (registering DOI) - 25 Nov 2024

Abstract

The issue of mycotoxin contamination in food is particularly important for consumer safety. The consumption of these fungi can cause genetic mutations or lead to the formation of cancer cells. For years, foods have been studied for this problem, but for table olives, there is currently a significant lack of scientific literature. This study aimed to point out the possible application of the Enzyme-Linked Immunosorbent Assay (ELISA) method for the detection of mycotoxins in table olives, assessing the presence of aflatoxins and ochratoxin A. Different tests were carried out on commercial and inoculated olives to assess the efficacy of the method by comparison with the conventional one, based on Liquid Chromatography–Tandem Mass Spectrometry (LC–MS/MS). Initial unsatisfactory results led us to refine the extraction method via the substitution of the chemical extractant 70% methanol with dichloromethane; this procedure allowed for improving the recovery of inoculated mycotoxins. The results show the effectiveness of the ELISA test, especially in mycotoxin recovery, after the modification of the extraction method. The recoveries increased for aflatoxins from 55% to over 70% and for ochratoxin A from 40% to over 55%. When samples were analyzed with commercial kits, the results showed some false positives, especially for the first sample of ochratoxin A, but the reliability of the ELISA method test was largely verified in the rest of the samples. The validity, the reduced cost, and the speed of application of the ELISA test make this method suitable as a control program for mycotoxin detection in table olives, which can be supported by LC-MS/MS analysis in case of positive results. Full article

(This article belongs to the Special Issue Novel Analyses of Hazards and Risks in Food Safety)

16 pages, 2473 KiB

Open AccessArticle

In Vitro and In Vivo Digestibility of Putative Nutraceutical Common-Bean-Derived Alpha-Amylase Inhibitors

by Krisztina Takács, András Nagy, Anna Jánosi, István Dalmadi and Anita Maczó

Appl. Sci. 2024, 14(23), 10935; https://doi.org/10.3390/app142310935 (registering DOI) - 25 Nov 2024

Abstract

The inhibition of the alpha-amylase digestive enzyme impedes starch digestion by blocking access to the active site of the enzyme, thereby playing a role in the prevention of obesity and type 2 diabetes. Plant-derived alpha-amylase inhibitors (αAIs) are promising nonpharmacological alternatives for the prevention of these diseases. Alpha-amylase inhibitor-1 (αAI-1) present in common bean (Phaseolus vulgaris) is derived from a precursor protein. In this study, the effect of digestion on the digestibility, immune reactivity, and bioactivity of αAI-1 was assessed from four varieties of Hungarian common bean (Phaseolus vulgaris), with special regard to the precursor protein. For this purpose, αAI-1 was tested in both matrix (native flour and cooked flour) and purified forms under in vitro and acute rat in vivo digestion experiments. The effect of digestion on αAI-1s was monitored by lab-on-a-chip (LOC) electrophoresis, SDS-PAGE/immunoblot, and inhibitory activity analyses by native PAGE. After both in vitro and in vivo digestion, we established that αAI-1 was not degraded even after 60 min gastric digestion and showed immune-reactive properties as well. Although the activity of the purified αAI-1 was lost, that of αAI-1 in the flour matrix (noncooked and cooked) was retained in the stomach. Presumably, in the beans, αAI-1 polypeptides became active due to the pepsin digestion of the precursor protein. The latter samples were also tested in vivo in the small intestine and their resistance and immune reactivity were observed, but αAI-1 did not show activity, as αAI-1 polypeptides were probably complexed by pancreatic amylases. From these results, we can assume that the αAI-1-rich bean protein preparation can affect the carbohydrate metabolism; thus, it could be a promising ingredient for weight loss purposes. Full article

(This article belongs to the Special Issue Advances in Food Metabolomics)

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9 pages, 416 KiB

Open AccessSystematic Review

The Role of the Endometrial Microbiota in Endometrial Cancer: A Systematic Review of the Literature

by Guglielmo Stabile, Alessandra Doria, Matteo Bruno, Marco D’Indinosante, Valerio Gallotta, Francesco Fanfani, Giovanni Scambia, Stefano Restaino, Giuseppe Vizzielli, Stefania Carlucci and Luigi Nappi

J. Clin. Med. 2024, 13(23), 7135; https://doi.org/10.3390/jcm13237135 (registering DOI) - 25 Nov 2024

Abstract

Background: Endometrial cancer is currently the sixth most frequent cancer in women, and scientific research is focusing on the search for particular features of the endometrium that may explain a further predisposition to the onset of endometrial cancer, aimed at improving knowledge of the pathogenetic factors of this disease. The aim of our review is to analyze in detail the results of the literature on the endometrial microbiota in patients with endometrial cancer and to investigate its role. Methods: We performed our research on the Pubmed, Web of Science, and Scopus databases. We searched up to December 2023 and considered manuscripts published from 2000. Only articles in English were included in the search. We excluded studies in which the endometrial microbiota were collected through the vagina or cervical canal. Results: We included in our review a total of five manuscripts at the end of the screening process, and the total number of patients involved was 190. Four studies considered only post-menopausal patients, while one study considered both pre- and post-menopausal patients. In all studies, the microbiota analysis was derived from a post-hysterectomy biopsy. From our review, it emerged that Bacteroidetes, Actinobacteria, Firmicutes, and Proteobacteria are the most represented bacteria in patients with endometrial cancer. These are both Gram-positive and Gram-negative, but predominantly anaerobic bacteria. Conclusions: The reduced microbial diversity and the presence of specific bacteria is often associated with endometrial cancer. Further work on larger population samples, and on healthy women and those affected by endometrial carcinoma, is needed to understand how the endometrial microbiota changes and influences the development of the tumor and whether intervening in the changes in the microbiota will have a therapeutic impact on endometrial carcinoma Full article

(This article belongs to the Section Obstetrics & Gynecology)

17 pages, 938 KiB

Open AccessReview

Myokines and Microbiota: New Perspectives in the Endocrine Muscle–Gut Axis

by Federica Saponaro, Andrea Bertolini, Riccardo Baragatti, Leonardo Galfo, Grazia Chiellini, Alessandro Saba and Giuseppina D’Urso

Nutrients 2024, 16(23), 4032; https://doi.org/10.3390/nu16234032 (registering DOI) - 25 Nov 2024

Abstract

This review explores the dual role of skeletal muscle as both a mechanical and endocrine organ, highlighting its contributions to overall health and its adaptability to various inputs such as nutrition, hormones, exercise, and injuries. In addition to its role in metabolism and energy conversion, skeletal muscle secretes signalling molecules called myokines (at rest) and exerkines (during/after physical exercise), which communicate with other organs like the brain, the cardiovascular system, and the immune system. Key molecules such as interleukins, irisin, and myostatin are discussed for their roles in mediating muscle health and inter-organ communication. This work also focuses on the muscle–gut axis, emphasising the bidirectional interaction between skeletal muscle and the gut microbiota, a complex ecosystem influencing immune defence, digestion, and metabolism. Muscle activity, particularly exercise, alters the gut microbial composition, promoting beneficial species, while gut-derived metabolites like short-chain fatty acids (SCFAs) impact muscle metabolism, mitochondrial function, and insulin sensitivity. Dysbiosis, or an imbalanced microbiota, can lead to muscle atrophy, inflammation, and metabolic dysfunction. This evidence highlights emerging research into myokines and exerkines as potential therapeutic targets for managing conditions like muscle decline, ageing, and metabolic diseases through muscle–gut interactions. Full article

(This article belongs to the Special Issue Nutrition–Microbiome Interaction in Healthy Metabolism)

28 pages, 1328 KiB

Open AccessArticle

Evaluation of Probiotic Potential and Functional Properties of Lactobacillus Strains Isolated from Dhan, Traditional Algerian Goat Milk Butter

by Mohamed Cherif Bentahar, Djilali Benabdelmoumene, Véronique Robert, Said Dahmouni, Wasim S. M. Qadi, Zineb Bengharbi, Philippe Langella, Bouasria Benbouziane, Ebtesam Al-Olayan, Esraa Adnan Dawoud Dawoud and Ahmed Mediani

Foods 2024, 13(23), 3781; https://doi.org/10.3390/foods13233781 (registering DOI) - 25 Nov 2024

Abstract

Goat milk butter, locally known as “Dhan,” from the Sfisfa region of Algeria, holds significant cultural and economic value. This study investigates the probiotic properties of lactic acid bacteria (LAB) present in Dhan, focusing particularly on Lactobacillus strains. Molecular identification using 16S rRNA revealed a dominance of Levilactobacillus brevis and Lactiplantibacillus plantarum, forming a substantial part of the bacterial profile. Three LAB isolates (DC01-A, DC04, and DC06) were selected from fresh samples, and rigorous analyses were performed to evaluate their probiotic properties. Safety assessments confirmed the absence of gelatinase, DNase, and haemolytic activities in all isolates. The isolates demonstrated high tolerance to bile salts and acidic conditions, along with the ability to survive simulated gastrointestinal digestion. Notably, strain DC06 exhibited exceptional survival at low pH (1.5) and high bile salt concentrations (0.15–0.3%). All isolates showed substantial growth in MRS medium with 2% phenol, although growth was significantly decreased at 5% phenol. Furthermore, our strains exhibited high adhesion rates to various solvents, demonstrating their potential for strong interaction with cell membranes. Specifically, adhesion to chloroform was observed at 98.26% for DC01-A, 99.30% for DC04, and 99.20% for DC06. With xylene, the adhesion rates were 75.94% for DC01-A, 61.13% for DC04, and 76.52% for DC06. The LAB strains demonstrated impressive growth in ethanol concentrations up to 12%, but their tolerance did not exceed this concentration. They also exhibited robust growth across temperatures from 10 °C to 37 °C, with strains DC04 and DC06 able to proliferate at 45 °C, though none survived at 50 °C. Additionally, the isolates showed significant resistance to oxidative stress induced by hydrogen peroxide (H₂O₂) and displayed medium to high autolytic activity, with rates of 50.86%, 37.53%, and 33.42% for DC01-A, DC04, and DC06, respectively. The cell-free supernatant derived from strain DC04 exhibited significant antimicrobial activity against the tested pathogens, while strain DC06 demonstrated moderate antioxidant activity with the highest DPPH scavenging rate at 68.56%, compared to the probiotic reference strain LGG at 61.28%. These collective findings not only suggest the probiotic viability of LAB strains found in Dhan but also highlight the importance of traditional food practises in contributing to health and nutrition. Consequently, this study supports the potential of traditional Dhan butter as a functional food and encourages further exploration of its health benefits. Full article

(This article belongs to the Section Food Microbiology)

17 pages, 8166 KiB

Open AccessArticle

Experimental Research on the Correction of Vortex Light Wavefront Distortion

by Yahang Ge and Xizheng Ke

Photonics 2024, 11(12), 1116; https://doi.org/10.3390/photonics11121116 (registering DOI) - 25 Nov 2024

Abstract

Wavefront distortion occurs when vortex beams are transmitted in the atmosphere. The turbulence effect greatly affects the transmission of information, so it is necessary to use adaptive optical correction technology to correct the wavefront distortion of the vortex beam at the receiving end. In this paper, a method of vortex wavefront distortion correction based on the deep deterministic policy gradient algorithm is proposed; this is a new correction method that can effectively handle high-dimensional state and action spaces and is especially suitable for correction problems in continuous action spaces. The entire system uses adaptive wavefront correction technology without a wavefront sensor. The simulation results show that the deep deterministic policy gradient algorithm can effectively correct the distorted vortex beams and improve the mode purity, and the intensity correlation coefficient of single-mode vortex light can be increased to about 0.88 and 0.69, respectively, under weak turbulence and strong turbulence, and the intensity coefficient of weak-turbulence multi-mode vortex light can be increased to about 0.96. The experimental results also show that the adaptive correction technology based on the deep deterministic policy gradient algorithm can effectively correct the wavefront distortion of vortex light. Full article

(This article belongs to the Section Optical Communication and Network)

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18 pages, 5378 KiB

Open AccessArticle

Scalp-Implanted Ultra-Wideband Circularly Polarized MIMO Antenna for Biotelemetry Systems

by Zhiwei Song, Youwei Shi, Xianren Zheng and Yuchao Wang

Sensors 2024, 24(23), 7522; https://doi.org/10.3390/s24237522 (registering DOI) - 25 Nov 2024

Abstract

This paper presents an innovative, compact, dual-element, implantable, ultra-wideband, circularly polarized multiple-input multiple-output (MIMO) antenna designed to operate within the 2.45 GHz industrial, scientific, and medical band, and both of its radiating units are circularly polarized antennas with polarization diversity. Specifically, antenna-1 exhibits left-handed circular polarization properties, while antenna-2 demonstrates right-handed circular polarization properties. The slots in the radiating patch and ground plane help the antenna achieve 690 MHz (2.14–2.83 GHz) ultra-wide bandwidth characteristics and circularly polarized characteristics. Additionally, a slit connecting two U-slots on the ground plane allows the antenna to achieve a wide effective circularly polarized axial ratio bandwidth of 400 MHz (2.23–2.63 GHz). The antenna is compact, with dimensions of 0.065 × 0.057 × 0.0042 λ₀³ (λ₀ represents the free-space wavelength corresponding to the lowest operating frequency). The proposed antenna system’s performance was evaluated with a seven-layer homogeneous human head model, a real human head model, and minced pork. This evaluation revealed that the antenna attained a peak gain of −24.1 dBi and an isolation level of 27.5 dB. Furthermore, the assessment included the antenna’s link margin (LM), key MIMO channel characteristics, and Specific Absorption Rate (SAR) metrics. The results indicate that the antenna performs exceptionally well. Full article

(This article belongs to the Special Issue Electromagnetic Waves, Antennas and Sensor Technologies in Modern Biomedical and Environmental Applications)

16 pages, 6905 KiB

Open AccessArticle

Analyzing Hydrodynamic Changes in Dubai Creek, UAE: A Pre- and Post-Extension Study

by Khaled Elkersh, Serter Atabay, Tarig Ali, Abdullah G. Yilmaz, Maruf Md. Mortula and Geórgenes H. Cavalcante

Hydrology 2024, 11(12), 202; https://doi.org/10.3390/hydrology11120202 (registering DOI) - 25 Nov 2024

Abstract

This paper presents a comparative study that examines the effects of the Dubai Creek extension on its hydrodynamics and water flushing dynamics. Dubai Creek (Khor Dubai) is a 24 km long artificial seawater stream located in the emirate of Dubai. The creek has experienced the impact of the rapid urbanization of Dubai and a major 13 km extension project, which connected the creek to the Arabian Gulf from the other side. In this paper, two-dimensional hydrodynamic and flushing models were created using Delft3D Flexible Mesh (2021.03) to investigate the water circulation and water quality of the creek before and after the extension. The hydrodynamic models were calibrated and validated to accurately simulate water levels and currents with correlation values close to 1 and very small RMSE and bias. Flushing models were created to simulate water renewal along the creek. The results of the flushing models showed a significant improvement in the flushing characteristics of pollutants in terms of the residence times of the extended creek (Existing Creek) model compared to the old one (Old Creek). This improvement emphasized the positive impact of the creek extension project on the local aquatic ecosystem and its overall water quality. Full article

(This article belongs to the Special Issue Hydrodynamics and Water Quality of Rivers and Lakes)

14 pages, 385 KiB

Open AccessArticle

The Effect of Risk Management on Direct and Indirect Capital Structure Deviations

by Xiaoyi Li and Yung-Ming Shiu

Risks 2024, 12(12), 186; https://doi.org/10.3390/risks12120186 (registering DOI) - 25 Nov 2024

Abstract

This study explores the effect of risk management on capital structure deviations. Specifically, we innovatively classify capital structure deviations into direct and indirect deviations, with our classification being based on deviations resulting mainly from changes in either actual or target leverage. Thus, if the variation in the actual leverage exceeds the variation in the target leverage, this deviation is considered direct. Conversely, if the target leverage varies more than the actual leverage, it is considered an indirect deviation. Our results reveal that risk management can help reduce these deviations, which mainly result from changes in actual leverage. We further demonstrate that insurers with direct deviations adjust their capital structure approximately 29.2% faster than insurers with indirect deviations. Full article

(This article belongs to the Special Issue Risk Management for Capital Markets)

14 pages, 853 KiB

Open AccessArticle

Prediction of China’s Polysilicon Prices: A Combination Model Based on Variational Mode Decomposition, Sparrow Search Algorithm and Long Short-Term Memory

by Jining Wang, Lin Jiang and Lei Wang

Mathematics 2024, 12(23), 3690; https://doi.org/10.3390/math12233690 (registering DOI) - 25 Nov 2024

Abstract

Given the non-stationarity, nonlinearity, and high complexity of polysilicon prices in the photovoltaic (PV) industry chain, this paper introduces upstream and downstream material prices of the PV industry chain and macroeconomic indicators as influencing factors. The VMD–SSA–LSTM combination model is constructed to predict polysilicon prices, which is based on Variational Mode Decomposition (VMD) and utilizes the Sparrow Search Algorithm (SSA) to optimize the Long Short-Term Memory (LSTM) network. The research shows that decomposing the original polysilicon time series using the VMD algorithm effectively extracts the main features of polysilicon price data, reducing data instability. By optimizing the learning rate, hidden layer nodes, and regularization coefficients of the LSTM model using the Sparrow Search Algorithm, the model achieves higher convergence accuracy. Compared to the traditional LSTM model and VMD–LSTM model, the VMD–SSA–LSTM model exhibits the smallest error and the highest goodness-of-fit on the polysilicon dataset, demonstrating higher predictive accuracy for polysilicon prices, which provides more accurate reference data for market analysis and pricing decisions of the polysilicon industry. Full article

25 pages, 3845 KiB

Open AccessArticle

Cross-Shaped Peg-in-Hole Autonomous Assembly System via BP Neural Network Based on Force/Moment and Visual Information

by Zheng Ma, Xiaoguang Hu and Yulin Zhou

Machines 2024, 12(12), 846; https://doi.org/10.3390/machines12120846 (registering DOI) - 25 Nov 2024

Abstract

Currently, research on peg-in-hole (PiH) compliant assembly is predominantly limited to circular pegs and holes, with insufficient exploration of various complex-shaped PiH tasks. Furthermore, the degree of freedom for rotation about the axis of the circular peg cannot be constrained after assembly, and few studies have covered the complete process from autonomous hole-searching to insertion. Based on the above problems, a novel cross-shaped peg and hole design has been devised. The center coordinates of the cross-hole are obtained during the hole-searching process using the three-dimensional reconstruction theory of a binocular stereo vision camera. During the insertion process, 26 contact states of the cross-peg and the cross-hole were classified, and the mapping relationship between the force-moment sensor and relative errors was established based on a backpropagation (BP) neural network, thus completing the task of autonomous PiH assembly. This system avoids hand-guiding, completely realizes the autonomous assembly task from hole-searching to insertion, and can be replaced by other structures of pegs and holes for repeated assembly after obtaining the accurate relative pose between two assembly platforms, which provides a brand-new and unified solution for complex-shaped PiH assembly. Full article

(This article belongs to the Section Robotics, Mechatronics and Intelligent Machines)

14 pages, 3263 KiB

Open AccessArticle

Chemical, In Cellulo, and In Silico Characterization of the Aminocholine Analogs of VG

by Stavroula Kostoudi, Nikolaos Iatridis, Dimitra Hadjipavlou-Litina, Eleni Pontiki and Georgios Pampalakis

Int. J. Mol. Sci. 2024, 25(23), 12656; https://doi.org/10.3390/ijms252312656 (registering DOI) - 25 Nov 2024

Abstract

V-type nerve agents are exceedingly toxic chemical warfare agents that irreversibly inhibit acetylcholinesterase (AChE), leading to acetylcholine accumulation in synapses and the disruption of neurotransmission. VG or O.O-diethyl S-(diethylamino)ethyl phosphorothiolate was the first compound of this class that was synthesized. The selenocholines (-Se-), cholines (-O-), and methylene-cholines (-CH₂-) analogs of V-agents have been synthesized and their anti-AChE activities reported. Nevertheless, the aminocholine derivatives have not been pursued. Here, we have designed and synthesized a series of phosphorylated aminocholines analogs of VG that were characterized by NMR spectroscopy (H1, C13, P31, and TOCSY). Their pharmacological properties were analyzed in silico, while their toxicological properties were in vitro investigated using the SH-SY5Y cellular model. Despite the drug likeness of the new compounds, these fail to inhibit AChE in vitro and in cellulo. This may be partially explained by the fact that aminocholine is not a good leaving group compared to thiocholine. Remarkably, one of the compounds (P4) was found to even increase the activity of AChE. These compounds may serve as new nerve agent mimics that are safer alternatives for testing countermeasures. Importantly, P4 may act as a lead compound for developing a new class of alternative nerve agent pretreatments that are safer from pyridostigmine. Full article

(This article belongs to the Section Biochemistry)

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Abstract

In this paper, the authors present the possibilities of transnational networking and developing innovative cultural routes through participatory research and creative presentations of European cultural heritage in special collections of Adriatic libraries. The purpose of the research, conducted in the framework of the course Travel Writing and Cultural Routes, was to identify collections that contain travel writing material related to the broader Euro-Mediterranean area and to enable its better visibility through the digitization and creation of new European cultural routes. The students, with the help of librarians at the University Library in Pula, explored special collections, such as the Marine Library, and proposed the creation of new cultural routes, following the itineraries of European travel writers in the Adriatic. The conducted research indicated collections and materials in heritage institutions (archives, libraries and museums) in Pula and Istria relevant to the topics of cultural routes and travel in Europe, as well as regional multicultural history. Libraries in Istria and Dalmatia have valuable collections of rare archival material related to European travels to the Adriatic. The cataloguing and digitisation of rare travel texts has the potential to raise awareness of these collections, adding to their significance for academic research and heritage-based tourism. Full article

16 pages, 2178 KiB

Open AccessArticle

Experimental Analysis of Mechanical Property Enhancement of Paper-Pulp-Based Packaging Materials Using Biodegradable Additives

by Amalka Indupama Samarathunga, Watagoda Gedara Chathura Madusanka Kulasooriya, Horawala Mahawaththage Dona Umesha Sewwandi, Vimukthi Vithanage, Ashan Induranga, Buddhika Sampath Kumara and Kaveenga Koswattage

Sustainability 2024, 16(23), 10310; https://doi.org/10.3390/su162310310 (registering DOI) - 25 Nov 2024

Abstract

Generally, paper-pulp-based materials are emerging in the packaging industry due to their high degree of biodegradability. Along with agricultural byproducts as an alternative, using additive or secondary materials in various processes and products has been a solution for implementing sustainability in material utilization. However, biodegradable materials still need to be improved due to the lack of properties which are essential for their use as packaging material. Currently, a number of research attempts have focused on enhancing the mechanical and thermal properties to increase the effectivity of those biodegradable materials for use as packaging material. The objective of this study is to analyze the effectivity of using sugarcane bagasse ash (SCBA) and wheat flour (starch) as a strengthening and thermal resistive additive. Due to its proven nano range particle size and fibrous nature, this material could positively affect the material properties. A total of twelve samples were prepared by varying the weight fraction of SCBA, white flour, and paper pulp. A compression molding method was used to prepare cylindrical samples with a diameter of 50 mm and a height of 55 mm under a compression load of 2 tonnes. Wet molded cylindrical blocks were oven-dried at

105^{\circ}

C for 48 h to remove excessive moisture from the samples. Subsequently, all the samples were dried further until no significant weight loss was observed after the drying process to ensure their uniform moisture conditions. The prepared samples were tested for compressive strength using a Universal Testing Machine (UTM). Both load and compressive stress acting on each sample were plotted against the deflection of the sample. For the analysis, the deflection of each sample was measured at 8.6 kN load and the sample with 10% SCBA and 12.5% starch exhibited the least displacement among all additives. The results show that the samples with 10% SCBA and 12.5% starch also had the highest compressive strength compared to the other samples. Further, samples with the same amount of SCBA were analyzed for thermal resistivity and to obtain the thermal behavior of samples which is crucial in food packaging.Overall, most of the SCBA and starch mixed samples showed superior compressive strength compared to the pure paper-pulp-based sample. Full article

(This article belongs to the Special Issue Sustainable Development of Composite Materials: From Smart Production to Optimal Operation)

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