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19 pages, 645 KiB  
Article
The Social Representation of Sustainable Mobility: An Exploratory Investigation on Social Media Networks
by Renata Metastasio, Elena Bocci, Paola Passafaro, Francesco Carnovale and Valeria Zenone
Sustainability 2024, 16(7), 2833; https://doi.org/10.3390/su16072833 (registering DOI) - 28 Mar 2024
Abstract
This paper analyzes the social representation (SR) of sustainable mobility as it emerges from social media networks. The role of social media (SM) as contexts of creation, negotiation, and diffusion of a mobility culture worldwide is discussed, together with the results of an [...] Read more.
This paper analyzes the social representation (SR) of sustainable mobility as it emerges from social media networks. The role of social media (SM) as contexts of creation, negotiation, and diffusion of a mobility culture worldwide is discussed, together with the results of an empirical investigation that explored the contents and structure of the discourse on “sustainable mobility” as it emerges from the posts published (in English) on two highly used social media (Facebook and TikTok) platforms during the years 2022 and 2023. First of all, the results confirm the relevance of social media as an indicator of ongoing trends in the evolution of mobility culture and the usefulness of S. Moscovici’s theory of social representations as a theoretical framework for analyzing such trends. In particular, several new trends in the SRs of sustainable mobility were identified. These include, for example, the decline in skeptical views and the rise of more optimistic ones, regarding the feasibility of changing people’s mobility styles worldwide. Such views appear to be fostered by the positive perception of new technological innovations (electric vehicles), as well as by their endorsement by both the business sector and governmental institutions. Practical implications and theoretical indications for future research are also outlined. Full article
(This article belongs to the Special Issue Smart Transportation, Urban Planning and Sustainability)
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29 pages, 13614 KiB  
Article
Comparative Evaluation of Three-Phase Three-Level Flying Capacitor and Stacked Polyphase Bridge GaN Inverter Systems for Integrated Motor Drives
by Gwendolin Rohner, Jonas Huber, Spasoje Miri? and Johann W. Kolar
Electronics 2024, 13(7), 1259; https://doi.org/10.3390/electronics13071259 (registering DOI) - 28 Mar 2024
Abstract
This article presents a comprehensive comparative evaluation of a three-phase Three-Level (3L) Flying Capacitor Converter (FCC) and a spbi, specifically a converter system formed by two Series-Stacked Two-Level three-phase Converters (2L-SSC), for the realization of a 7.5 kW Integrated Motor Drive (IMD) with [...] Read more.
This article presents a comprehensive comparative evaluation of a three-phase Three-Level (3L) Flying Capacitor Converter (FCC) and a spbi, specifically a converter system formed by two Series-Stacked Two-Level three-phase Converters (2L-SSC), for the realization of a 7.5 kW Integrated Motor Drive (IMD) with a high short-term overload capability. The 2L-SSC requires a motor with two three-phase windings and a split DC-link, but uses standard six-switch, two-level transistor configurations. In contrast, the bridge legs of the 3lfcc feature flying capacitors whose voltages must be actively balanced. Despite the 800 V DC-link voltage, both topologies employ the same set of 650 V GaN power transistors, i.e., the same total chip area, and if operated at the same switching frequency, show identical semiconductor losses. edm damage of the motor bearings is a relevant issue caused by the common-mode (CM) voltages of the inverter stage. The high effective switching frequency of the 3lfcc and the possibility of CM voltage canceling in the 2L-SSC facilitate mitigation of edm by means of CM chokes, whereby a substantially smaller CM choke with lower losses suffices for the 2L-SSC; based on exemplary designs, the 2L-SSC features only about 75% of the total volume and 85% of the nominal losses of the 3lfcc. If, alternatively, motor-friendliness is maximized by including DC-referenced sine-wave output filters, the 3lfcc’s higher effective switching frequency and the 2L-SSC’s need for two sets of filters due to the dual-winding-set motor change the outcome. In this case, the 3lfcc features only about 60% of the volume and only about 55% of the 2L-SSC’s nominal losses. Full article
(This article belongs to the Section Power Electronics)
22 pages, 9418 KiB  
Article
A Polyvinylpyrrolidone Nanofibrous Sensor Doubly Decorated with Mesoporous Graphene to Selectively Detect Acetic Acid Vapors
by Paolo Papa, Emiliano Zampetti, Fabricio Nicolas Molinari, Fabrizio De Cesare, Corrado Di Natale, Giovanna Tranfo and Antonella Macagnano
Sensors 2024, 24(7), 2174; https://doi.org/10.3390/s24072174 (registering DOI) - 28 Mar 2024
Abstract
An original approach has been proposed for designing a nanofibrous (NF) layer using UV-cured polyvinylpyrrolidone (PVP) as a matrix, incorporating mesoporous graphene carbon (MGC) nanopowder both inside and outside the fibers, creating a sandwich-like structure. This architecture is intended to selectively adsorb and [...] Read more.
An original approach has been proposed for designing a nanofibrous (NF) layer using UV-cured polyvinylpyrrolidone (PVP) as a matrix, incorporating mesoporous graphene carbon (MGC) nanopowder both inside and outside the fibers, creating a sandwich-like structure. This architecture is intended to selectively adsorb and detect acetic acid vapors, which are known to cause health issues in exposed workers. The nanocomposite MGC-PVP-NFs layer was fabricated through electrospinning deposition onto interdigitated microelectrodes (IDEs) and stabilized under UV–light irradiation. To enhance the adhesion of MGC onto the surface of the nanocomposite polymeric fibers, the layer was dipped in a suspension of polyethyleneimine (PEI) and MGC. The resulting structure demonstrated promising electrical and sensing properties, including rapid responses, high sensitivity, good linearity, reversibility, repeatability, and selectivity towards acetic acid vapors. Initial testing was conducted in a laboratory using a bench electrometer, followed by validation in a portable sensing device based on consumer electronic components (by ARDUINO®). This portable system was designed to provide a compact, cost-effective solution with high sensing capabilities. Under room temperature and ambient air conditions, both laboratory and portable tests exhibited favorable linear responses, with detection limits of 0.16 and 1 ppm, respectively. Full article
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18 pages, 532 KiB  
Article
Distributed Adaptive Tracking Control of Hidden Leader-Follower Multi-Agent Systems with Unknown Parameters
by Jie Yang and Byung Gook Lee
Mathematics 2024, 12(7), 1013; https://doi.org/10.3390/math12071013 (registering DOI) - 28 Mar 2024
Abstract
The distributed leader-follower control of multi-agent systems is discussed. Each agent is expressed in a discrete-time and non-linear dynamic model with an unknown parameter and can be affected by its neighbors’ history information. For each agent, to identify the parameter, one switching set [...] Read more.
The distributed leader-follower control of multi-agent systems is discussed. Each agent is expressed in a discrete-time and non-linear dynamic model with an unknown parameter and can be affected by its neighbors’ history information. For each agent, to identify the parameter, one switching set of the parameter estimates is constructed and the optimal parameter estimate is chosen based on the index switching function. Using the given desired reference signal, the leader agent’s control law is designed, and relying on the neighbors’ history information, each follower agent’s local control law is designed. With the designed distributed tracking adaptive control laws, the whole system tracks the given desired reference signal, and in the face of strong couplings the closed-loop system ultimately reaches an agreement. Finally, by comparing simulations of the control strategy with a normal projection algorithm, the results indicate that the adaptive control method with a switching set of the parameter estimates is effective in improving the control performance. Full article
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17 pages, 2766 KiB  
Article
Multi-Objective Optimization of Process Parameters in Laser DED Ni-Based Powder on Steel Rail Using Response Surface Design
by Juncai Li, Yue Yang, Liaoyuan Chen, Tianbiao Yu, Ji Zhao and Zixuan Wang
Coatings 2024, 14(4), 401; https://doi.org/10.3390/coatings14040401 (registering DOI) - 28 Mar 2024
Abstract
With the rise of global industrialization, the requirements for the operating speed and carrying capacity of high-speed trains are increasingly higher. Because the wear and tear of rails gradually increases during the running of high-speed trains, strengthening or repairing rail surfaces is of [...] Read more.
With the rise of global industrialization, the requirements for the operating speed and carrying capacity of high-speed trains are increasingly higher. Because the wear and tear of rails gradually increases during the running of high-speed trains, strengthening or repairing rail surfaces is of paramount significance. Laser-directed energy deposition (DED) exhibits significant advantages in improving surface hardness, corrosion resistance, and abrasion resistance. Because of the multiple interacting optimization objectives, the development of a multi-objective optimization method for process parameters is significant for improving DED deposition quality. Response surface design employs multivariate quadratic regression equations to fit the functional relationship between the factors and the responses, which can be employed to find the optimal process parameters and solve multivariate problems. This study develops a multi-objective optimization model with response surface design and 2D process mappings to visually analyze the effects of scanning speed, laser power, and powder feed rate on aspect ratio, dilution rate, and microhardness. The optimal combination of process parameters for Ni-based alloys on U71Mn rail is a laser power of 431 W, a scanning speed of 5.34 mm/s, and a powder feed rate of 1.03 r/min. In addition, a multi-physics field finite element model is developed to analyze the evolution mechanism of the microstructure from the bottom to the top of the single track. This study can provide theoretical and technical support for the surface strengthening or repair of U71Mn rail. Full article
(This article belongs to the Special Issue Surface Engineering Processes for Reducing Friction and Wear)
18 pages, 3968 KiB  
Article
Bayesian Gaussian Mixture Models for Enhanced Radar Sensor Modeling: A Data-Driven Approach towards Sensor Simulation for ADAS/AD Development
by Kelvin Walenta, Simon Genser and Selim Solmaz
Sensors 2024, 24(7), 2177; https://doi.org/10.3390/s24072177 (registering DOI) - 28 Mar 2024
Abstract
In the realm of road safety and the evolution toward automated driving, Advanced Driver Assistance and Automated Driving (ADAS/AD) systems play a pivotal role. As the complexity of these systems grows, comprehensive testing becomes imperative, with virtual test environments becoming crucial, especially for [...] Read more.
In the realm of road safety and the evolution toward automated driving, Advanced Driver Assistance and Automated Driving (ADAS/AD) systems play a pivotal role. As the complexity of these systems grows, comprehensive testing becomes imperative, with virtual test environments becoming crucial, especially for handling diverse and challenging scenarios. Radar sensors are integral to ADAS/AD units and are known for their robust performance even in adverse conditions. However, accurately modeling the radar’s perception, particularly the radar cross-section (RCS), proves challenging. This paper adopts a data-driven approach, using Gaussian mixture models (GMMs) to model the radar’s perception for various vehicles and aspect angles. A Bayesian variational approach automatically infers model complexity. The model is expanded into a comprehensive radar sensor model based on object lists, incorporating occlusion effects and RCS-based detectability decisions. The model’s effectiveness is demonstrated through accurate reproduction of the RCS behavior and scatter point distribution. The full capabilities of the sensor model are demonstrated in different scenarios. The flexible and modular framework has proven apt for modeling specific aspects and allows for an easy model extension. Simultaneously, alongside model extension, more extensive validation is proposed to refine accuracy and broaden the model’s applicability. Full article
(This article belongs to the Section Vehicular Sensing)
21 pages, 1209 KiB  
Review
The 125th Anniversary of Aspirin—The Story Continues
by Oliver Werz, Hans Stettler, Christoph Theurer and Jens Seibel
Pharmaceuticals 2024, 17(4), 437; https://doi.org/10.3390/ph17040437 (registering DOI) - 28 Mar 2024
Abstract
The year 2024 marks the 125th anniversary of aspirin, still one of the most frequently used drugs worldwide. Despite its veritable age, it is still relevant in pharmacotherapy and its use has spread to new areas over time. Due to aspirin’s multiple pharmacological [...] Read more.
The year 2024 marks the 125th anniversary of aspirin, still one of the most frequently used drugs worldwide. Despite its veritable age, it is still relevant in pharmacotherapy and its use has spread to new areas over time. Due to aspirin’s multiple pharmacological actions unified in one single molecule (i.e., analgesic, antipyretic, anti-inflammatory, antithrombotic, and antiviral effects), it continues to attract considerable attention in the scientific community and is subject to intense basic and clinical research. In fact, recent results confirmed aspirin’s potential role as an antiviral drug and as an agent that can block harmful platelet functions in inflammatory/immunological processes. These features may open up new horizons for this ancient drug. The future of aspirin looks, therefore, bright and promising. Aspirin is not yet ready for retirement; on the contrary, its success story continues. This 125th anniversary paper will concisely review the various therapeutic uses of aspirin with a particular emphasis on the latest research results and their implications (e.g., use as an antiviral agent). In addition, the reader is provided with future perspectives for this remarkable drug. Full article
(This article belongs to the Section Pharmacology)
20 pages, 1256 KiB  
Article
The Dual Role of Neutrophil Extracellular Traps (NETs) in Sepsis and Ischemia-Reperfusion Injury: Comparative Analysis across Murine Models
by Antonia Kiwit, Yuqing Lu, Moritz Lenz, Jasmin Knopf, Christoph Mohr, Yannick Ledermann, Michaela Klinke-Petrowsky, Laia Pagerols Raluy, Konrad Reinshagen, Martin Herrmann, Michael Boettcher and Julia Elrod
Int. J. Mol. Sci. 2024, 25(7), 3787; https://doi.org/10.3390/ijms25073787 (registering DOI) - 28 Mar 2024
Abstract
A better understanding of the function of neutrophil extracellular traps (NETs) may facilitate the development of interventions for sepsis. The study aims to investigate the formation and degradation of NETs in three murine sepsis models and to analyze the production of reactive oxygen [...] Read more.
A better understanding of the function of neutrophil extracellular traps (NETs) may facilitate the development of interventions for sepsis. The study aims to investigate the formation and degradation of NETs in three murine sepsis models and to analyze the production of reactive oxygen species (ROS) during NET formation. Murine sepsis was induced by midgut volvulus (720° for 15 min), cecal ligation and puncture (CLP), or the application of lipopolysaccharide (LPS) (10 mg/kg body weight i.p.). NET formation and degradation was modulated using mice that were genetically deficient for peptidyl arginine deiminase-4 (PAD4-KO) or DNase1 and 1L3 (DNase1/1L3-DKO). After 48 h, mice were killed. Plasma levels of circulating free DNA (cfDNA) and neutrophil elastase (NE) were quantified to assess NET formation and degradation. Plasma deoxyribonuclease1 (DNase1) protein levels, as well as tissue malondialdehyde (MDA) activity and glutathione peroxidase (GPx) activity, were quantified. DNase1 and DNase1L3 in liver, intestine, spleen, and lung tissues were assessed. The applied sepsis models resulted in a simultaneous increase in NET formation and oxidative stress. NET formation and survival differed in the three models. In contrast to LPS and Volvulus, CLP-induced sepsis showed a decreased and increased 48 h survival in PAD4-KO and DNase1/1L3-DKO mice, when compared to WT mice, respectively. PAD4-KO mice showed decreased formation of NETs and ROS, while DNase1/1L3-DKO mice with impaired NET degradation accumulated ROS and chronicled the septic state. The findings indicate a dual role for NET formation and degradation in sepsis and ischemia-reperfusion (I/R) injury: NETs seem to exhibit a protective capacity in certain sepsis paradigms (CLP model), whereas, collectively, they seem to contribute adversely to scenarios where sepsis is combined with ischemia-reperfusion (volvulus). Full article
(This article belongs to the Special Issue Recent Advances in Neutrophil Extracellular Traps (NETs))
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18 pages, 295 KiB  
Article
Boyer–Lindquist Space-Times and Beyond: Metamaterial Analogues for ArbitrarySpace-Times
by Sebastian Schuster and Matt Visser
Universe 2024, 10(4), 159; https://doi.org/10.3390/universe10040159 (registering DOI) - 28 Mar 2024
Abstract
Analogue space-times (and in particular metamaterial analogue space-times) have a long varied and rather complex history. Much of the previous related work to this field has focused on spherically symmetric models; however, axial symmetry is much more relevant for mimicking astrophysically interesting systems [...] Read more.
Analogue space-times (and in particular metamaterial analogue space-times) have a long varied and rather complex history. Much of the previous related work to this field has focused on spherically symmetric models; however, axial symmetry is much more relevant for mimicking astrophysically interesting systems that are typically subject to rotation. Now it is well known that physically reasonable stationary axisymmetric space-times can, under very mild technical conditions, be put into Boyer–Lindquist form. Unfortunately, a metric presented in Boyer–Lindquist form is not well adapted to the “quasi-Cartesian” metamaterial analysis that we developed in our previous articles on “bespoke analogue space-times”. In the current article, we shall first focus specifically on various space-time metrics presented in Boyer–Lindquist form, and subsequently determine a suitable set of equivalent metamaterial susceptibility tensors in a laboratory setting. We shall then turn to analyzing generic space-times, not even necessarily stationary, again determining a suitable set of equivalent metamaterial susceptibility tensors. Perhaps surprisingly, we find that the well-known ADM formalism proves to be not particularly useful, and that it is instead the dual “threaded” (Kaluza–Klein–inspired) formalism that provides much more tractable results. While the background laboratory metric is (for mathematical simplicity and physical plausibility) always taken to be Riemann flat, we will allow for arbitrary curvilinear coordinate systems on the flat background space-time. Finally, for completeness, we shall reconsider spherically symmetric space-times, but now in general spherical polar coordinates rather than quasi-Cartesian coordinates. In summary, this article provides a set of general-purpose calculational tools that can readily be adapted for mimicking various interesting (curved) space-times by using nontrivial susceptibility tensors in general (background-flat) laboratory settings. Full article
(This article belongs to the Special Issue Analogue Gravity)
25 pages, 2117 KiB  
Article
Effects of Supplementation with Microalgae Extract from Phaeodactylum tricornutum (Mi136) to Support Benefits from a Weight Management Intervention in Overweight Women
by Broderick Dickerson, Jonathan Maury, Victoria Jenkins, Kay Nottingham, Dante Xing, Drew E. Gonzalez, Megan Leonard, Jacob Kendra, Joungbo Ko, Choongsung Yoo, Sarah Johnson, Rémi Pradelles, Martin Purpura, Ralf J?ger, Ryan Sowinski, Christopher J. Rasmussen and Richard B. Kreider
Nutrients 2024, 16(7), 990; https://doi.org/10.3390/nu16070990 (registering DOI) - 28 Mar 2024
Abstract
Background: Microalgae like Phaeodactylum tricornutum (PT) contain the carotenoid, fucoxanthin, which has been purported to promote fat loss, lower blood lipids, and improve glucose management. This study examined whether dietary supplementation with microalgae extracts from PT containing 4.4 mg/d of fucoxanthin affects changes [...] Read more.
Background: Microalgae like Phaeodactylum tricornutum (PT) contain the carotenoid, fucoxanthin, which has been purported to promote fat loss, lower blood lipids, and improve glucose management. This study examined whether dietary supplementation with microalgae extracts from PT containing 4.4 mg/d of fucoxanthin affects changes in body composition or health markers in overweight women during an exercise and diet intervention. Materials and Methods: A total of 37 females (28.6 ± 7.9 years, 80.2 ± 14.9 kg, 29.6 ± 3.8 kg/m², 41.4 ± 4.2% fat) fasted for 12 h, donated a fasting blood sample, completed health and mood state inventories, and undertook body composition, health, and exercise assessments. In a counterbalanced, randomized, and double-blind manner, participants ingested a placebo (PL), or microalgae extract of Phaeodactylum tricornutum standardized to 4.4 mg of fucoxanthin (FX) for 12 weeks while participating in a supervised exercise program that included resistance-training and walking (3 days/week) with encouragement to accumulate 10,000 steps/day on remaining days of the week. The diet intervention involved reducing energy intake by about -300 kcal/d (i.e., ≈1400–1600 kcals/d, 55% carbohydrate, 30% fat, 15% protein) to promote a −500 kcal/d energy deficit with exercise. Follow-up testing was performed at 6 and 12 weeks. A general linear model (GLM) with repeated measures statistical analysis was used to analyze group responses and changes from baseline with 95% confidence intervals. Results: Dietary supplementation with microalgae extract from PT containing fucoxanthin for 12 weeks did not promote additional weight loss or fat loss in overweight but otherwise healthy females initiating an exercise and diet intervention designed to promote modest weight loss. However, fucoxanthin supplementation preserved bone mass, increased bone density, and saw greater improvements in walking steps/day, resting heart rate, aerobic capacity, blood lipid profiles, adherence to diet goals, functional activity tolerance, and measures of quality of life. Consequently, there appears to be some benefit to supplementing microalgae extract from PT containing fucoxanthin during a diet and exercise program. Registered clinical trial #NCT04761406. Full article
(This article belongs to the Section Nutrition in Women)
15 pages, 833 KiB  
Review
Salmonella Control in Swine: A Thoughtful Discussion of the Pre- and Post-Harvest Control Approaches in Industrialized Countries
by Ana Carvajal, Melvin Kramer and Héctor Argüello
Animals 2024, 14(7), 1035; https://doi.org/10.3390/ani14071035 (registering DOI) - 28 Mar 2024
Abstract
Pork is among the major sources of human salmonellosis in developed countries. Since the 1990s, different surveys and cross-sectional studies, both national and international (i.e., the baseline studies performed in the European Union), have revealed and confirmed the widespread non-typhoidal Salmonella serotypes in [...] Read more.
Pork is among the major sources of human salmonellosis in developed countries. Since the 1990s, different surveys and cross-sectional studies, both national and international (i.e., the baseline studies performed in the European Union), have revealed and confirmed the widespread non-typhoidal Salmonella serotypes in pigs. A number of countries have implemented control programs with different approaches and degrees of success. The efforts could be implemented either at farms, in post-harvest stages, or both. The current review revises the current state of the art in Salmonella in swine, the control programs ongoing or conducted in the past, and their strengths and failures, with particular attention to the weight of pre- and post-harvest control and the implications that both have for the success of interventions or mitigation after outbreaks. This review provides a novel perspective on Salmonella control in swine, a matter that still includes uncertainties and room for improvement as a question of public health and One Health. Full article
(This article belongs to the Special Issue Salmonella and Salmonellosis: Implications in Public Health)
16 pages, 371 KiB  
Review
Marine Natural Products Rescuing the Eye: A Narrative Review
by Filippo Lixi, Livio Vitiello and Giuseppe Giannaccare
Mar. Drugs 2024, 22(4), 155; https://doi.org/10.3390/md22040155 (registering DOI) - 28 Mar 2024
Abstract
Different degrees of visual impairment lead to a decrease in patient wellbeing, which has an adverse effect on many facets of social and professional life. Eye disorders can affect several parts of the eye, most notably the retina and the cornea, and the [...] Read more.
Different degrees of visual impairment lead to a decrease in patient wellbeing, which has an adverse effect on many facets of social and professional life. Eye disorders can affect several parts of the eye, most notably the retina and the cornea, and the impacted areas might share a common form of cellular damage or dysfunction (such as inflammation, oxidative stress and neuronal degeneration). Considering that marine organisms inhabit a broad variety of marine habitats, they display a great degree of chemical diversity. As a result, molecules with a marine origin are receiving more and more attention in the hopes of developing novel therapeutic approaches. For instance, fucoxanthin has been demonstrated to be effective in protecting the retina against photo-induced damage, while largazole, astaxanthin and spirulina have all shown antioxidant, anti-inflammatory and antiapoptotic activities that can be useful for the management of several ocular diseases, such as age-related macular degeneration and ocular surface disorders. The aim of this review is to analyze the scientific literature relating to the therapeutic effects on the eye of the main natural marine products, focusing on their mechanism of action and potential clinical uses for the management of ocular diseases. Full article
(This article belongs to the Special Issue Marine Natural Products with Anti-aging Activity)
14 pages, 2480 KiB  
Article
Characterization of Potting Epoxy Resins Performance Parameters Based on a Viscoelastic Constitutive Model
by Lin Yang, Anxin Ding, Mi Xu, Yuefang Li, Xianhang Zhao, Jingxuan Peng and Xiang Li
Polymers 2024, 16(7), 930; https://doi.org/10.3390/polym16070930 (registering DOI) - 28 Mar 2024
Abstract
To describe the evolution of residual stresses in epoxy resin during the curing process, a more detailed characterization of its viscoelastic properties is necessary. In this study, we have devised a simplified apparatus for assessing the viscoelastic properties of epoxy resin. This apparatus [...] Read more.
To describe the evolution of residual stresses in epoxy resin during the curing process, a more detailed characterization of its viscoelastic properties is necessary. In this study, we have devised a simplified apparatus for assessing the viscoelastic properties of epoxy resin. This apparatus employs a confining cylinder to restrict the circumferential and radial deformations of the material. Following the application of load by the testing machine, the epoxy resin sample gradually reduces the gap between its surface and the inner wall of the confining cylinder, ultimately achieving full contact and establishing a continuous interface. By recording the circumferential stress–strain on the outer surface of the confining cylinder, we can deduce the variations in material bulk and shear moduli with time. This characterization spans eight temperature points surrounding the glass transition temperature, revealing the bulk and shear relaxation moduli of the epoxy resin. Throughout the experiments, the epoxy resin’s viscoelastic response demonstrated a pronounced time-temperature dependency. Below the glass transition temperature, the stress relaxation response progressively accelerated with increasing temperature, while beyond the glass transition temperature, the stress relaxation time underwent a substantial reduction. By applying the time-temperature superposition principle, it is possible to construct the relaxation master curves for the bulk and shear moduli of the epoxy resin. By fitting the data, we can obtain expressions for the constitutive model describing the viscoelastic behavior of the epoxy resin. In order to validate the reliability of the test results, a uniaxial tensile relaxation test was conducted on the epoxy resin casting body. The results show good agreement between the obtained uniaxial relaxation modulus curves and those derived from the bulk and shear relaxation modulus equations, confirming the validity of both the device design and the testing methodology. Full article
(This article belongs to the Special Issue Epoxy Thermoset Polymer Composites)
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14 pages, 2362 KiB  
Article
Exploring the Chemical Profile, In Vitro Antioxidant and Anti-Inflammatory Activities of Santolina rosmarinifolia Extracts
by Janos Schmidt, Kata Juhasz and Agnes Bona
Molecules 2024, 29(7), 1515; https://doi.org/10.3390/molecules29071515 (registering DOI) - 28 Mar 2024
Abstract
In this study, the phytochemical composition, in vitro antioxidant, and anti-inflammatory effects of the aqueous and 60% ethanolic (EtOH) extracts of Santolina rosmarinifolia leaf, flower, and root were examined. The antioxidant activity of S. rosmarinifolia extracts was determined by 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and [...] Read more.
In this study, the phytochemical composition, in vitro antioxidant, and anti-inflammatory effects of the aqueous and 60% ethanolic (EtOH) extracts of Santolina rosmarinifolia leaf, flower, and root were examined. The antioxidant activity of S. rosmarinifolia extracts was determined by 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays. The total phenolic content (TPC) of the extracts was measured by the Folin–Ciocalteu assay. The anti-inflammatory effect of the extracts was monitored by the Griess assay. The chemical composition of S. rosmarinifolia extracts was analysed using the LC-MS technique. According to our findings, 60% EtOH leaf extracts showed the highest Trolox equivalent antioxidant capacity (TEAC) values in both ABTS (8.39 ± 0.43 µM) and DPPH (6.71 ± 0.03 µM) antioxidant activity assays. The TPC values of the samples were in good correspondence with the antioxidant activity measurements and showed the highest gallic acid equivalent value (130.17 ± 0.01 µg/mL) in 60% EtOH leaf extracts. In addition, the 60% EtOH extracts of the leaves were revealed to possess the highest anti-inflammatory effect. The LC-MS analysis of S. rosmarinifolia extracts proved the presence of ascorbic acid, catalpol, chrysin, epigallocatechin, geraniol, isoquercitrin, and theanine, among others, for the first time. However, additional studies are needed to investigate the direct relationship between the chemical composition and physiological effects of the herb. The 60% EtOH extracts of S. rosmarinifolia leaves are potential new sources of natural antioxidants and anti-inflammatory molecules in the production of novel nutraceutical products. Full article
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14 pages, 609 KiB  
Review
The Relationship between Posture and Muscle Tensive Dysphonia in Teachers: A Systematic Scoping Review
by Roberta Franzone, Luca Petrigna, Daniele Signorelli and Giuseppe Musumeci
J. Funct. Morphol. Kinesiol. 2024, 9(2), 60; https://doi.org/10.3390/jfmk9020060 (registering DOI) - 28 Mar 2024
Abstract
Teachers usually present work-related pain such as neck pain. Their posture could be the cause of these problems; indeed, it is often a sway-back posture. Furthermore, teachers can also experience problems with their voice such as dysphonia, specifically muscle tension dysphonia (MTD). This [...] Read more.
Teachers usually present work-related pain such as neck pain. Their posture could be the cause of these problems; indeed, it is often a sway-back posture. Furthermore, teachers can also experience problems with their voice such as dysphonia, specifically muscle tension dysphonia (MTD). This scoping review aims to find the correlation between teachers’ posture and MTD. It also studies how a posture-based treatment can influence this disorder. Randomized controlled trials, controlled clinical trials, prospective cohort studies, and cross-sectional studies that considered the relationship between posture and MTD and that included teachers in their sample. The search led to an initial number of 396 articles; after the screening process, a final number of eight articles were included. A total of 303 patients were analyzed and all showed altered alignment of the head around the cervical spine with hypertonus of the cricothyroid, suprahyoid, and sternocleidomastoid muscles. Although MTD is a disorder with a multifactorial etiology, the articles revealed a correlation between posture and MTD related to a forward protraction of the cervical spine with a hypertonus of the laryngeal and hyoid musculature. This study also detected that an intervention in posture could reduce vocal disorders. Full article
(This article belongs to the Section Functional Anatomy and Musculoskeletal System)
15 pages, 453 KiB  
Review
Role of SGLT2 Inhibitors, DPP-4 Inhibitors, and Metformin in Pancreatic Cancer Prevention
by Tooba Laeeq, Maheen Ahmed, Hina Sattar, Muhammad Hamayl Zeeshan and Meher Binte Ali
Cancers 2024, 16(7), 1325; https://doi.org/10.3390/cancers16071325 (registering DOI) - 28 Mar 2024
Abstract
Pancreatic carcinoma is a highly aggressive tumor that usually presents when it has already metastasized. Therapeutic options for cure remain scarce and rely on combination chemotherapy with limited sustainability. Diabetes is considered an important risk factor for the development of pancreatic cancer due [...] Read more.
Pancreatic carcinoma is a highly aggressive tumor that usually presents when it has already metastasized. Therapeutic options for cure remain scarce and rely on combination chemotherapy with limited sustainability. Diabetes is considered an important risk factor for the development of pancreatic cancer due to the production of proinflammatory cytokines, which result in increased cell proliferation. More than half of patients diagnosed with pancreatic cancer eventually develop diabetes due to the destruction of insulin-producing cells. The interlinkage of both diseases might identify a possible preventative strategy for reducing the incidence of pancreatic carcinoma. This study reviewed the recent literature on the association between pancreatic cancer risk and SGLT2 inhibitors, GLP-1 RA, DPP-4 inhibitors, and biguanides. There are mixed data regarding the relationship between GLP-1 RA and DPP-4 inhibitors and pancreatic cancer, with some trials suggesting that they might increase the risk. In contrast, studies have mostly revealed that SGLT2 inhibitors have an antiproliferative effect on various tumors, such as liver, pancreatic, prostate, bowel, lung, and breast carcinoma, which might be due to their mechanism of blockage of reabsorption of glucose by cells, lowering the amount of available glucose for the growth of tumor cells. Metformin, the first-line agent for diabetes, has also been shown to be associated with decreasing pancreatic cancer risk and improving prognosis in those who already have the disease. Dedicated trials are needed to further delineate the association of antidiabetic drugs with the risk of pancreatic cancer in the general population, as previous studies have mostly focused on diabetic patients. Full article
(This article belongs to the Section Cancer Epidemiology and Prevention)
16 pages, 1007 KiB  
Article
Fatigue Life Estimation of Critical Components in a Motor-Energized Spring Operating Mechanism Based on Theory of Reliability
by Hongming Ma, Guochao Qian, Jie Zhang, Jiali Chen, Fusheng Zhou, Pengfeng Qiu, Aohua Zhang, Ting Wang, Xiaofei Yao and Zhiyuan Liu
Energies 2024, 17(7), 1623; https://doi.org/10.3390/en17071623 (registering DOI) - 28 Mar 2024
Abstract
High-voltage switchgear is a key control and protection unit in power systems. The reliable operation of the operating mechanism is essential for the reliable opening and closing of the switchgear. This is a vital guarantee for the safety and stability of the power [...] Read more.
High-voltage switchgear is a key control and protection unit in power systems. The reliable operation of the operating mechanism is essential for the reliable opening and closing of the switchgear. This is a vital guarantee for the safety and stability of the power systems. The spring operating mechanism is a commonly used actuator for circuit breakers at 12–252 kV. However, a reliability estimation method that is convenient, practical and accurate is still lacking. The aim of this paper is to explore a reliability estimation method based on a stress–strength interference reliability theory and a fatigue life theory. The changing rules of the reliability of the main axis, and the closing pawl and opening pawl in the spring operating mechanism during operations, are achieved. The accuracy of the calculated reliability based on theories of stress–strength interference and fatigue life is verified by adopting a test data statistical reliability model based on Weibull distribution. The results show that the reliability estimation method based on stress–strength interference and fatigue life theories has a high degree of confidence. The maximum tolerance is 0.024. The study would help in providing a useful reference for the optimization and durability estimation of a spring operating mechanism and its key components in high-voltage circuit breakers. Full article
(This article belongs to the Section F: Electrical Engineering)
16 pages, 4358 KiB  
Article
Algorithm for Point Cloud Dust Filtering of LiDAR for Autonomous Vehicles in Mining Area
by Xianyao Jiang, Yi Xie, Chongning Na, Wenyang Yu and Yu Meng
Sustainability 2024, 16(7), 2827; https://doi.org/10.3390/su16072827 (registering DOI) - 28 Mar 2024
Abstract
With the continuous development of the transformation of the “smart mine” in the mineral industry, the use of sensors in autonomous trucks has become very common. However, the driving of trucks causes the point cloud collected by through Light Detection and Ranging (LiDAR) [...] Read more.
With the continuous development of the transformation of the “smart mine” in the mineral industry, the use of sensors in autonomous trucks has become very common. However, the driving of trucks causes the point cloud collected by through Light Detection and Ranging (LiDAR) to contain dust points, leading to a significant decline in its detection performance, which makes it easy for vehicles to have failures at the perceptual level. In order to solve this problem, this study proposes a LiDAR point cloud denoising method for the quantitative analysis of laser reflection intensity and spatial structure. This method uses laser reflectivity as the benchmark template, constructs the initial confidence level template and initially screens out the sparse dust point cloud. The results are analyzed through the Euclidean distance of adjacent points, and the confidence level in the corresponding template is reduced for rescreening. The experimental results show that our method can significantly filter dust point cloud particles while retaining the rich environmental information of data. The computational load caused by filtering is far lower than that of other methods, and the overall operation efficiency of the system has no significant delay. Full article
(This article belongs to the Special Issue Advances in Intelligent and Sustainable Mining)
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20 pages, 11541 KiB  
Article
The Beneficial Effect of a TPMS-Based Fillet Shape on the Mechanical Strength of Metal Cubic Lattice Structures
by Christian Iandiorio, Gianmarco Mattei, Emanuele Marotta, Girolamo Costanza, Maria Elisa Tata and Pietro Salvini
Materials 2024, 17(7), 1553; https://doi.org/10.3390/ma17071553 (registering DOI) - 28 Mar 2024
Abstract
The goal of this paper is to improve the mechanical strength-to-weight ratios of metal cubic lattice structures using unit cells with fillet shapes inspired by triply periodic minimal surfaces (TPMSs). The lattice structures here presented were fabricated from AA6082 aluminum alloy using lost-PLA [...] Read more.
The goal of this paper is to improve the mechanical strength-to-weight ratios of metal cubic lattice structures using unit cells with fillet shapes inspired by triply periodic minimal surfaces (TPMSs). The lattice structures here presented were fabricated from AA6082 aluminum alloy using lost-PLA processing. Static and dynamic flat and wedge compression tests were conducted on samples with varying fillet shapes and fill factors. Finite element method simulations followed the static tests to compare numerical predictions with experimental outcomes, revealing a good agreement. The TPSM-type fillet shape induces a triaxial stress state that significantly improves the mechanical strength-to-weight ratio compared to fillet radius-free lattices, which was also confirmed by analytical considerations. Dynamic tests exhibited high resistance to flat impacts, while wedge impacts, involving a high concentrated-load, brought out an increased sensitivity to strain rates with a short plastic deformation followed by abrupt fragmentation, indicating a shift towards brittle behavior. Full article
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20 pages, 6592 KiB  
Article
Integrated Proteomics and Metabolomics of Safflower Petal Wilting and Seed Development
by Delphine Vincent, Priyanka Reddy and Daniel Isenegger
Biomolecules 2024, 14(4), 414; https://doi.org/10.3390/biom14040414 (registering DOI) - 28 Mar 2024
Abstract
Safflower (Carthamus tinctorius L.) is an ancient oilseed crop of interest due to its diversity of end-use industrial and food products. Proteomic and metabolomic profiling of its organs during seed development, which can provide further insights on seed quality attributes to assist [...] Read more.
Safflower (Carthamus tinctorius L.) is an ancient oilseed crop of interest due to its diversity of end-use industrial and food products. Proteomic and metabolomic profiling of its organs during seed development, which can provide further insights on seed quality attributes to assist in variety and product development, has not yet been undertaken. In this study, an integrated proteome and metabolic analysis have shown a high complexity of lipophilic proteins and metabolites differentially expressed across organs and tissues during seed development and petal wilting. We demonstrated that these approaches successfully discriminated safflower reproductive organs and developmental stages with the identification of 2179 unique compounds and 3043 peptides matching 724 unique proteins. A comparison between cotyledon and husk tissues revealed the complementarity of using both technologies, with husks mostly featuring metabolites (99%), while cotyledons predominantly yielded peptides (90%). This provided a more complete picture of mechanisms discriminating the seed envelope from what it protected. Furthermore, we showed distinct molecular signatures of petal wilting and colour transition, seed growth, and maturation. We revealed the molecular makeup shift occurring during petal colour transition and wilting, as well as the importance of benzenoids, phenylpropanoids, flavonoids, and pigments. Finally, our study emphasizes that the biochemical mechanisms implicated in the growing and maturing of safflower seeds are complex and far-reaching, as evidenced by AraCyc, PaintOmics, and MetaboAnalyst mapping capabilities. This study provides a new resource for functional knowledge of safflower seed and potentially further enables the precision development of novel products and safflower varieties with biotechnology and molecular farming applications. Full article
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20 pages, 2337 KiB  
Article
Building Minimized Epigenetic Clock by iPlex MassARRAY Platform
by Ekaterina Davydova, Alexey Perenkov and Maria Vedunova
Genes 2024, 15(4), 425; https://doi.org/10.3390/genes15040425 (registering DOI) - 28 Mar 2024
Abstract
Epigenetic clocks are valuable tools for estimating both chronological and biological age by assessing DNA methylation levels at specific CpG dinucleotides. While conventional epigenetic clocks rely on genome-wide methylation data, targeted approaches offer a more efficient alternative. In this study, we explored the [...] Read more.
Epigenetic clocks are valuable tools for estimating both chronological and biological age by assessing DNA methylation levels at specific CpG dinucleotides. While conventional epigenetic clocks rely on genome-wide methylation data, targeted approaches offer a more efficient alternative. In this study, we explored the feasibility of constructing a minimized epigenetic clock utilizing data acquired through the iPlex MassARRAY technology. The study enrolled a cohort of relatively healthy individuals, and their methylation levels of eight specific CpG dinucleotides in genes SLC12A5, LDB2, FIGN, ACSS3, FHL2, and EPHX3 were evaluated using the iPlex MassARRAY system and the Illumina EPIC array. The methylation level of five studied CpG sites demonstrated significant correlations with chronological age and an acceptable convergence of data obtained by the iPlex MassARRAY and Illumina EPIC array. At the same time, the methylation level of three CpG sites showed a weak relationship with age and exhibited a low concordance between the data obtained from the two technologies. The construction of the epigenetic clock involved the utilization of different machine-learning models, including linear models, deep neural networks (DNN), and gradient-boosted decision trees (GBDT). The results obtained from these models were compared with each other and with the outcomes generated by other well-established epigenetic clocks. In our study, the TabNet architecture (deep tabular data learning architecture) exhibited the best performance (best MAE = 5.99). Although our minimized epigenetic clock yielded slightly higher age prediction errors compared to other epigenetic clocks, it still represents a viable alternative to the genome-wide epigenotyping array. Full article
(This article belongs to the Section Epigenomics)
27 pages, 2365 KiB  
Article
Data-Driven Techniques for Short-Term Electricity Price Forecasting through Novel Deep Learning Approaches with Attention Mechanisms
by Vasileios Laitsos, Georgios Vontzos, Dimitrios Bargiotas, Aspassia Daskalopulu and Lefteri H. Tsoukalas
Energies 2024, 17(7), 1625; https://doi.org/10.3390/en17071625 (registering DOI) - 28 Mar 2024
Abstract
The electricity market is constantly evolving, being driven by factors such as market liberalization, the increasing use of renewable energy sources (RESs), and various economic and political influences. These dynamics make it challenging to predict wholesale electricity prices. Accurate short-term forecasting is crucial [...] Read more.
The electricity market is constantly evolving, being driven by factors such as market liberalization, the increasing use of renewable energy sources (RESs), and various economic and political influences. These dynamics make it challenging to predict wholesale electricity prices. Accurate short-term forecasting is crucial to maintaining system balance and addressing anomalies such as negative prices and deviations from predictions. This paper investigates short-term electricity price forecasting using historical time series data and employs advanced deep learning algorithms. First, four deep learning models are implemented and proposed, which are a convolutional neural network (CNN) with an integrated attention mechanism, a hybrid CNN followed by a gated recurrent unit model (CNN-GRU) with an attention mechanism, and two ensemble learning models, which are a soft voting ensemble and a stacking ensemble model. Also, the optimized version of a transformer model, the Multi-Head Attention model, is introduced. Finally, the perceptron model is used as a benchmark for comparison. Our results show excellent prediction accuracy, particularly in the hybrid CNN-GRU model with attention, thereby achieving a mean absolute percentage error (MAPE) of 6.333%. The soft voting ensemble model and the Multi-Head Attention model also performed well, with MAPEs of 6.125% and 6.889%, respectively. These findings are significant, as previous studies have not shown high performance with transformer models and attention mechanisms. The presented results offer promising insights for future research in this field. Full article
(This article belongs to the Special Issue Energy, Electrical and Power Engineering 2024)
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18 pages, 2475 KiB  
Article
Generation of Construction Scheduling through Machine Learning and BIM: A Blueprint
by Mazen A. Al-Sinan, Abdulaziz A. Bubshait and Zainab Aljaroudi
Buildings 2024, 14(4), 934; https://doi.org/10.3390/buildings14040934 (registering DOI) - 28 Mar 2024
Abstract
Recent advancements in machine learning (ML) applications have set the stage for the development of autonomous construction project scheduling systems. This study presents a blueprint to demonstrate how construction project schedules can be generated automatically by employing machine learning (ML) and building information [...] Read more.
Recent advancements in machine learning (ML) applications have set the stage for the development of autonomous construction project scheduling systems. This study presents a blueprint to demonstrate how construction project schedules can be generated automatically by employing machine learning (ML) and building information modeling (BIM). The proposed solution should utilize building information modeling (BIM) international foundation class (IFC) 3D files of previous projects to train the ML model. The training schedules (the dependent variable) are intended to be prepared by an experienced scheduler, and the 3D BIM files should be used as the source of the scheduled activities. Using the ML model can enhance the generalization of model application to different construction projects. Furthermore, the cost and required resources for each activity could be generated. Accordingly, unlike other solutions, the proposed solution could sequence activities based on an ML model instead of manually developed constraint matrices. The proposed solution is intended to generate the duration, cost, and required resources for each activity. Full article
(This article belongs to the Section Construction Management, and Computers & Digitization)
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