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15 pages, 1033 KiB  
Article
Transcranial Pulse Stimulation in Alzheimer’s: Long-Term Feasibility and a Multifocal Treatment Approach
by Celine Cont-Richter, Nathalie Stute, Anastasia Galli, Christina Schulte and Lars Wojtecki
Brain Sci. 2025, 15(8), 830; https://doi.org/10.3390/brainsci15080830 (registering DOI) - 1 Aug 2025
Abstract
Background/Objectives: Neuromodulation is under investigation as a possibly effective add-on therapy in Alzheimer’s disease (AD). While transcranial pulse stimulation (TPS) has shown positive short-term effects, long-term effects have not yet been fully explored. This study aims to evaluate the long-term feasibility, safety, and [...] Read more.
Background/Objectives: Neuromodulation is under investigation as a possibly effective add-on therapy in Alzheimer’s disease (AD). While transcranial pulse stimulation (TPS) has shown positive short-term effects, long-term effects have not yet been fully explored. This study aims to evaluate the long-term feasibility, safety, and potential cognitive benefits of TPS over one year in patients with Alzheimer’s disease, focusing on domains such as memory, speech, orientation, visuo-construction, and depressive symptoms. Methods: We analyzed preliminary data from the first ten out of thirty-five patients enrolled in a prospective TPS study who completed one year of follow-up and were included in a dedicated long-term database. The protocol consisted of six initial TPS sessions over two weeks, followed by monthly booster sessions delivering 6000 pulses each for twelve months. Patients underwent regular neuropsychological assessments using the Alzheimer Disease Assessment Scale (ADAS), Mini-Mental Status Examination (MMSE), Montreal Cognitive Assessment (MoCA), and Beck Depression Inventory (BDI-II). All adverse events (AEs) were documented and monitored throughout the study. Results: Adverse events occurred in less than 1% of stimulation sessions and mainly included mild focal pain or transient unpleasant sensations, as well as some systemic behavioral or vigilance changes, particularly in patients with underlying medical conditions, with some potentially related to the device’s stimulation as adverse device reactions (ADRs). Cognitive test results showed significant improvement after the initial stimulation cycle (ADAS total improved significantly after the first stimulation cycle (M_pre = 28.44, M_post = 18.56; p = 0.001, d = 0.80, 95% CI (0.36, 1.25)), with stable scores across all domains over one year. Improvements were most notable in memory, speech, and mood. Conclusions: TPS appears to be a generally safe and feasible add-on treatment for AD, although careful patient selection and monitoring are advised. While a considerable number of participants were lost to follow-up for various reasons, adverse events and lack of treatment effect were unlikely primary causes. A multifocal stimulation approach (F-TOP2) is proposed to enhance effects across more cognitive domains. Full article
(This article belongs to the Special Issue Noninvasive Neuromodulation Applications in Research and Clinics)
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27 pages, 5196 KiB  
Article
Impact of Hydrogen Release on Accidental Consequences in Deep-Sea Floating Photovoltaic Hydrogen Production Platforms
by Kan Wang, Jiahui Mi, Hao Wang, Xiaolei Liu and Tingting Shi
Hydrogen 2025, 6(3), 52; https://doi.org/10.3390/hydrogen6030052 - 29 Jul 2025
Viewed by 169
Abstract
Hydrogen is a potential key component of a carbon-neutral energy carrier and an input to marine industrial processes. This study examines the consequences of coupled hydrogen release and marine environmental factors during floating photovoltaic hydrogen production (FPHP) system failures. A validated three-dimensional numerical [...] Read more.
Hydrogen is a potential key component of a carbon-neutral energy carrier and an input to marine industrial processes. This study examines the consequences of coupled hydrogen release and marine environmental factors during floating photovoltaic hydrogen production (FPHP) system failures. A validated three-dimensional numerical model of FPHP comprehensively characterizes hydrogen leakage dynamics under varied rupture diameters (25, 50, 100 mm), transient release duration, dispersion patterns, and wind intensity effects (0–20 m/s sea-level velocities) on hydrogen–air vapor clouds. FLACS-generated data establish the concentration–dispersion distance relationship, with numerical validation confirming predictive accuracy for hydrogen storage tank failures. The results indicate that the wind velocity and rupture size significantly influence the explosion risk; 100 mm ruptures elevate the explosion risk, producing vapor clouds that are 40–65% larger than 25 mm and 50 mm cases. Meanwhile, increased wind velocities (>10 m/s) accelerate hydrogen dilution, reducing the high-concentration cloud volume by 70–84%. Hydrogen jet orientation governs the spatial overpressure distribution in unconfined spaces, leading to considerable shockwave consequence variability. Photovoltaic modules and inverters of FPHP demonstrate maximum vulnerability to overpressure effects; these key findings can be used in the design of offshore platform safety. This study reveals fundamental accident characteristics for FPHP reliability assessment and provides critical insights for safety reinforcement strategies in maritime hydrogen applications. Full article
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22 pages, 1839 KiB  
Article
Development of a Clinical Guideline for Managing Knee Osteoarthritis in Portugal: A Physiotherapist-Centered Approach
by Ricardo Maia Ferreira and Rui Soles Gonçalves
Osteology 2025, 5(3), 23; https://doi.org/10.3390/osteology5030023 - 22 Jul 2025
Viewed by 304
Abstract
Background/Objectives: Knee osteoarthritis is one of the most significant diseases globally and in Portugal. Despite the availability of international guidelines, there is a lack of tailored, evidence-based recommendations specifically for Portuguese physiotherapists to manage their knee osteoarthritis patients with non-pharmacological and non-surgical [...] Read more.
Background/Objectives: Knee osteoarthritis is one of the most significant diseases globally and in Portugal. Despite the availability of international guidelines, there is a lack of tailored, evidence-based recommendations specifically for Portuguese physiotherapists to manage their knee osteoarthritis patients with non-pharmacological and non-surgical interventions. This study aimed to develop a clinical practice guideline that integrates the latest international evidence with local clinical practice data to enhance patient outcomes. Methods: To achieve the objective, a comprehensive search was conducted in November 2024 across major health-related databases, to identify robust and recent evidence regarding the efficacy of non-pharmacological and non-surgical interventions, as well as their usage in the national context. Two key sources were identified: An umbrella and a mixed-methods study. Data from both sources were independently reviewed and integrated through a comparative analysis to identify interventions with robust scientific support and high local acceptability. Recommendations were then formulated and categorized into gold (strong), silver (moderate), and bronze (weak) levels based on evidence quality and clinical relevance. A decision-making flowchart was developed to support guideline implementation and clinical usage. Results: The integrated analysis identified three gold-level interventions, namely Nutrition/Weight Loss, Resistance Exercise, and Self-care/Education. Five silver-level recommendations were Aerobic Exercise, Balneology/Spa, Extracorporeal Shockwave Therapy, Electrical Stimulation, and Manual Therapy. Similarly, five bronze-level recommendations comprised Kinesio Taping, Stretching, Ultrasound Therapy, Thermal Agents, and Walking Aids. Conclusions: This clinical practice guideline provides a context-specific, evidence-based framework for Portuguese physiotherapists managing knee osteoarthritis. By bridging international evidence with local clinical practice, the guideline aims to facilitate optimal patient care and inform future research and guideline updates. Full article
(This article belongs to the Special Issue Advances in Bone and Cartilage Diseases)
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24 pages, 8171 KiB  
Article
An Improved Adaptive Car-Following Model Based on the Unscented Kalman Filter for Vehicle Platoons’ Speed Control
by Caixia Huang, Wu Tang, Jiande Wang and Zhiyong Zhang
Machines 2025, 13(7), 569; https://doi.org/10.3390/machines13070569 - 1 Jul 2025
Viewed by 286
Abstract
This study proposes an adaptive car-following model based on the unscented Kalman filter algorithm to enable coordinated speed control in vehicle platoons and to address key limitations present in conventional car-following models. Traditional models generally assume a fixed maximum speed within the optimal [...] Read more.
This study proposes an adaptive car-following model based on the unscented Kalman filter algorithm to enable coordinated speed control in vehicle platoons and to address key limitations present in conventional car-following models. Traditional models generally assume a fixed maximum speed within the optimal velocity function, which constrains effective platoon speed regulation across road segments with varying speed limits and lacks adaptability to dynamic scenarios such as changes in the platoon leader’s speed or substitution of the lead vehicle. The proposed adaptive model utilizes state estimation based on the unscented Kalman filter to dynamically identify each vehicle’s maximum achievable speed and to adjust inter-vehicle constraints, thereby enforcing a unified speed reference across the platoon. By estimating these maximum speeds and transmitting them to individual follower vehicles via vehicle-to-vehicle communication, the model promotes smooth acceleration and deceleration behavior, reduces headway variability, and mitigates shockwave propagation within the platoon. Simulation studies—covering both single-leader acceleration and intermittent acceleration scenarios—demonstrate that, compared with conventional car-following models, the adaptive model based on the unscented Kalman filter achieves superior speed synchronization, improved headway stability, and smoother acceleration transitions. These enhancements lead to substantial improvements in traffic flow efficiency and string stability. The proposed approach offers a practical solution for coordinated platoon speed control in intelligent transportation systems, with promising application prospects for real-world implementation. Full article
(This article belongs to the Special Issue Intelligent Control and Active Safety Techniques for Road Vehicles)
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14 pages, 921 KiB  
Article
Physiotherapy Management of Plantar Fasciitis: A National Cross-Sectional Survey in Saudi Arabia
by Abdulmajeed Muhaysin Alnefaie, Hosam Alzahrani and Mansour Abdullah Alshehri
J. Clin. Med. 2025, 14(13), 4584; https://doi.org/10.3390/jcm14134584 - 27 Jun 2025
Viewed by 481
Abstract
Background/Objectives: Plantar fasciitis is the most common cause of heel pain, affecting 4–7% of the general population. Physiotherapy is a key component of conservative management. However, there is limited evidence on how physiotherapists in Saudi Arabia manage this condition. This study aimed [...] Read more.
Background/Objectives: Plantar fasciitis is the most common cause of heel pain, affecting 4–7% of the general population. Physiotherapy is a key component of conservative management. However, there is limited evidence on how physiotherapists in Saudi Arabia manage this condition. This study aimed to investigate current physiotherapy practices for plantar fasciitis in Saudi Arabia and assess their alignment with international clinical guidelines. Methods: A cross-sectional survey was conducted among licensed physiotherapists practicing in Saudi Arabia who had treated patients with plantar fasciitis. An online questionnaire, adapted from a validated UK-based survey, gathered data on participant demographics, service characteristics, diagnostic criteria, treatment goals, outcome measures, and intervention strategies. Descriptive statistics were used for analysis. Results: A total of 399 physiotherapists participated. Diagnosis was mainly based on clinical signs such as pain during plantar fascia stretch (72.9%), early morning pain (70.4%), and medial heel tenderness (69.4%). Common goals of intervention included pain reduction (93.4%), functional improvement (69.9%), and patient education (57.3%). Pain scales (74.9%) and functional tests (49.1%) were the most frequently used outcome measures. Interventions such as exercise therapy (92.0%), stretching (89.4%), and strengthening (84.7%) were widely used. More advanced modalities like shockwave therapy and dry needling were less frequently reported. Conclusions: Physiotherapy practices largely align with international guidelines. However, variation in outcome assessments and underuse of advanced modalities indicate the need for national clinical guidelines and targeted training programs. These steps may promote more consistent, evidence-based care and improve patient outcomes in Saudi Arabia. Full article
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35 pages, 5219 KiB  
Review
Pulsed Power Plasma Stimulation: A Comprehensive Review and Field Insights
by Son T. Nguyen, Mohamed E.-S. El-Tayeb, Mohamed Adel Gabry and Mohamed Y. Soliman
Energies 2025, 18(13), 3334; https://doi.org/10.3390/en18133334 - 25 Jun 2025
Viewed by 546
Abstract
Pulsed Power Plasma Stimulation (3PS) represents a promising and environmentally favorable alternative to conventional well stimulation techniques for enhancing subsurface permeability. This comprehensive review tracks the evolution of plasma-based rock stimulation, offering insights from key laboratory, numerical, and field-scale studies. The review begins [...] Read more.
Pulsed Power Plasma Stimulation (3PS) represents a promising and environmentally favorable alternative to conventional well stimulation techniques for enhancing subsurface permeability. This comprehensive review tracks the evolution of plasma-based rock stimulation, offering insights from key laboratory, numerical, and field-scale studies. The review begins with foundational electrohydraulic discharge concepts and progresses through the evolution of Pulsed Arc Electrohydraulic Discharge (PAED) and the more advanced 3PS systems. High-voltage, ultrafast plasma discharges generate mechanical shockwaves and localized thermal effects that result in complex fracture networks, particularly in tight and crystalline formations. Compared to conventional well stimulation techniques, 3PS reduces water use, avoids chemical additives, and minimizes induced seismicity. Laboratory studies demonstrate significant improvements in permeability, porosity, and fracture intensity, while field trials show an increase in production from oil, gas, and geothermal wells. However, 3PS faces some limitations such as short stimulation radii and logistical constraints in wireline-based delivery systems. Emerging technologies like plasma-assisted drilling and hybrid PDC–plasma tools offer promising integration pathways. Overall, 3PS provides a practical, scalable, low-impact stimulation approach with broad applicability across energy sectors, especially in environmentally sensitive or water-scarce regions. Full article
(This article belongs to the Special Issue Pulsed Power Science and High Voltage Discharge)
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29 pages, 7811 KiB  
Article
Dynamic Response of Reinforced Concrete Columns Subjected to Air and Underwater Explosions
by Getu Abyu, Girum Urgessa and Ameen Topa
Dynamics 2025, 5(3), 23; https://doi.org/10.3390/dynamics5030023 - 20 Jun 2025
Viewed by 492
Abstract
This research explores how RC columns respond to blast-induced dynamic effects, with a novel focus on partially submerged scenarios, bridging a gap between air blast and underwater explosion (UNDEX) research. Using advanced finite element modeling in LS-DYNA, the study captures the unique behavior [...] Read more.
This research explores how RC columns respond to blast-induced dynamic effects, with a novel focus on partially submerged scenarios, bridging a gap between air blast and underwater explosion (UNDEX) research. Using advanced finite element modeling in LS-DYNA, the study captures the unique behavior of RC columns under mixed-media conditions, where shockwaves propagate through water and air interfaces. Comprehensive parametric analyses explore the influence of charge size, blast stand-off, and depth of water, revealing distinct dampening mechanisms and structural responses. Key findings include a measurable reduction in peak displacement of partially submerged explosions compared to fully submerged explosions, attributed to the moderating effects of the water–air interface. A total of 60 simulation cases were conducted to systematically analyze partially submerged scenarios, providing robust insights into energy transmission and damage mechanisms. The numerical models, validated against published experimental data by others, demonstrate the accuracy of computational modeling in simulating damage profiles, displacement histories, and energy dissipation trends. This research offers practical implications for designing resilient RC structures in coastal and maritime environments. The results contribute significantly to the field of blast mechanics, advancing our understanding of mixed-media shockwave dynamics and their impact on critical infrastructure. Full article
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6 pages, 177 KiB  
Commentary
Commentary: Treating Diseases from Alzheimer’s to Parkinson’s Using Transcranial Pulse Stimulation: Mechanistic Insights, Recent Evidence, and Ethical Considerations
by Lars Wojtecki
NeuroSci 2025, 6(2), 56; https://doi.org/10.3390/neurosci6020056 - 17 Jun 2025
Viewed by 660
Abstract
Transcranial pulse stimulation (TPS) is a non-invasive neuromodulation method that uses, high-intensity acoustic shockwaves to deliver focused mechanical stimulation to neural tissue with minimal thermal effects. The mechanism of action includes but is not limited to promotion of blood flow and angiogenesis through [...] Read more.
Transcranial pulse stimulation (TPS) is a non-invasive neuromodulation method that uses, high-intensity acoustic shockwaves to deliver focused mechanical stimulation to neural tissue with minimal thermal effects. The mechanism of action includes but is not limited to promotion of blood flow and angiogenesis through mechanotransduction. Clinical data to date are limited and preliminary. In Alzheimer’s disease (AD), TPS has demonstrated cognitive and mood improvements in pilot studies and secondary endpoint analysis in first randomized trials. The enhancement of gamma-band oscillations and network connectivity has been reported. Clinical observations in Parkinson’s disease (PD) suggest TPS as a hypothesis-generating approach to address non-motor symptoms—such as depression, cognitive decline, and the freezing of gait—through theoretical modulation of basal ganglia–cortical circuits. TPS is CE-marked in Europe for AD and shows a favorable safety profile; however, ethical considerations arise from the limited evidence base, potential impairment of patient autonomy and judgment in dementia, and the risk of withholding established treatments. TPS should only be offered under structured scientific protocols or within patient registries to ensure rigorous oversight. Ensuring that consent processes account for cognitive capacity, and that TPS is applied as adjunct rather than replacement therapy, is paramount. Future research must include large-scale randomized controlled trials (RCTs), standardize stimulation protocols, deepen mechanistic insight, and embed robust ethical frameworks. Full article
24 pages, 2252 KiB  
Article
rESWT in Shoulder Periarthritis: Does the Protocol Intensity Matter?—A Quasi-Experimental Non-Randomized Comparative Study
by Diana-Lidia Tache-Codreanu, Iuliana David, Ana-Maria Tache-Codreanu, Corina Sporea, Claudia-Camelia Burcea, Dan Corneliu Blendea, Maria-Veronica Morcov and Ioana Elena Cioca
Life 2025, 15(6), 922; https://doi.org/10.3390/life15060922 - 6 Jun 2025
Viewed by 538
Abstract
Radial extracorporeal shockwave therapy (rESWT) is used in the rehabilitation of patients with shoulder periarthritis (SP) to promote tendon regeneration. This quasi-experimental non-randomized comparative study included 36 cases of SP, divided into two groups, and aimed to comparatively investigate the analgesic and functional [...] Read more.
Radial extracorporeal shockwave therapy (rESWT) is used in the rehabilitation of patients with shoulder periarthritis (SP) to promote tendon regeneration. This quasi-experimental non-randomized comparative study included 36 cases of SP, divided into two groups, and aimed to comparatively investigate the analgesic and functional effects of two different rESWT protocols. In Group One, the protocol involved an energy level of 210 J/session, a frequency of 10 Hz, and 2500 impulses per session. In Group Two, the protocol used an energy level of 190 J/session, a frequency of 10–15 Hz, and 2000 impulses per session. Treatments were administered over three sessions in Group One and five sessions in Group Two, with one-week intervals between sessions. Both rESWT protocols were combined with a physical therapy program consisting of ten daily sessions of analgesic physiotherapy and kinesiotherapy. Before and after the rehabilitation program, patients were assessed for pain intensity using the visual analog scale (VAS) and shoulder function using range of motion (ROM) measurements (via goniometry) and the Shoulder Pain and Disability Index (SPADI). Significantly better outcomes were observed in Group One (p < 0.001), particularly in terms of pain reduction and improvements in shoulder functionality, especially external rotation. These results support the effectiveness of the rESWT protocol used in Group One, which combined lower energy and frequency levels with a higher number of impulses over fewer sessions. Full article
(This article belongs to the Special Issue Physical Rehabilitation for Musculoskeletal Disorders)
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31 pages, 10078 KiB  
Article
Dynamic Response of Bottom-Sitting Steel Shell Structures Subjected to Underwater Shock Waves
by Fantong Lin, Xianxiang Zhou, Lan Xiao, Ziye Liu and Chaojia Liu
Infrastructures 2025, 10(6), 130; https://doi.org/10.3390/infrastructures10060130 - 28 May 2025
Viewed by 312
Abstract
This study examines the dynamic response of bottom-sitting steel shell structures subjected to underwater shock waves. A computational framework integrating the Arbitrary Lagrangian Eulerian (ALE) method was implemented in finite-element analysis to simulate three-dimensional interactions between shock waves and curved shell geometries (hemispherical [...] Read more.
This study examines the dynamic response of bottom-sitting steel shell structures subjected to underwater shock waves. A computational framework integrating the Arbitrary Lagrangian Eulerian (ALE) method was implemented in finite-element analysis to simulate three-dimensional interactions between shock waves and curved shell geometries (hemispherical and cylindrical configurations). An analysis of the impacts of shock-wave propagation media, explosive distance, charge equivalence, hydrostatic pressure, and shell thickness on the dynamic response of these bottom-sitting shell structures is conducted. The findings reveal that the deformation of semi-spherical steel shells subjected to underwater shock waves is significantly greater than that of shells subjected to air shock waves, with effective stress reaching up to 831.4 MPa underwater. The mechanical deformation of curved steel shells exhibits a gradual increase with increasing explosive equivalents. The center displacement of the hemispherical shell at 800 kg equivalent is 6 times that at 50 kg equivalent. Within the range of 0 to 2.0092 MPa, hydrostatic pressure leads to an approximate 26.34% increase in the center vertical displacement of the semi-cylindrical shell compared with 0 MPa, while restricting horizontal convex deformation. Increasing thickness from 0.025 m to 0.05 m results in a reduction of approximately 60% in the center vertical displacement of the semi-cylindrical shell. These quantitative correlations provide critical benchmarks for enhancing the blast resilience of underwater foundation systems. Full article
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22 pages, 4862 KiB  
Article
Exploring the Impact of Strut Geometry on Strut-Braced Wing Configurations
by Mihai-Vlăduț Hothazie, Daniel-Eugeniu Crunțeanu, Mihai-Victor Pricop and Ionuț Bunescu
Aerospace 2025, 12(6), 473; https://doi.org/10.3390/aerospace12060473 - 27 May 2025
Viewed by 354
Abstract
The anticipated growth of the aviation industry has driven regulators to establish stringent targets for achieving net-zero greenhouse gas emissions, which are challenging to meet with conventional aircraft configurations. The strut-braced wing configuration has emerged as a promising alternative for improving aerodynamic efficiency. [...] Read more.
The anticipated growth of the aviation industry has driven regulators to establish stringent targets for achieving net-zero greenhouse gas emissions, which are challenging to meet with conventional aircraft configurations. The strut-braced wing configuration has emerged as a promising alternative for improving aerodynamic efficiency. This study investigates the aerodynamic performance of such a configuration using a high-fidelity computational fluid dynamics analysis, conducted in two phases. The first phase involves a parametric study examining the effects of two key parameters: the length and the tilt angle of the strut’s elbow. The reference configuration is based on the strut braced wing configuration from the Platform for Aircraft Drag Reduction Innovation workshop. Building on the insights from the parametric study, the second phase involves an optimization of the strut’s geometry, focusing on minimizing aerodynamic drag. The results demonstrate an 11.5% reduction in the drag coefficient while maintaining the same lift coefficient, primarily attributed to a decrease in shockwave interactions within the strut–wing gap. These findings, combined with the parametric study, provide valuable insights into the influence of strut geometric parameters on drag minimization, highlighting their potential role in advancing sustainable aircraft design. Full article
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14 pages, 1633 KiB  
Article
Hydrodynamic Cavitation in Shockwave-Power-Reactor-Assisted Biodiesel Production in Continuous from Soybean and Waste Cooking Oil
by James R. Vera-Rozo, Edison A. Caicedo-Peñaranda and José M. Riesco-Avila
Energies 2025, 18(11), 2761; https://doi.org/10.3390/en18112761 - 26 May 2025
Viewed by 460
Abstract
The transesterification process for biodiesel production is constrained by high thermal input, prolonged residence time, and intensive mechanical agitation. This study investigates process intensification via hydrodynamic cavitation using a custom-built Shockwave Power Reactor (SPR), enabling continuous biodiesel synthesis from soybean and used cooking [...] Read more.
The transesterification process for biodiesel production is constrained by high thermal input, prolonged residence time, and intensive mechanical agitation. This study investigates process intensification via hydrodynamic cavitation using a custom-built Shockwave Power Reactor (SPR), enabling continuous biodiesel synthesis from soybean and used cooking oils. A statistically designed experimental matrix was applied to evaluate the reactor’s transient–stable thermal regime and the influence of operational parameters: rotor speed (1700–3415 rpm), volumetric flow rate (60–105 mL/min), methanol-to-oil molar ratio (6:1 to 12:1), and alkali catalyst type (NaOH or KOH). For benchmarking, conventional alkaline transesterification was optimized. The FAME yields from the SPR system exceeded 96.5% and complied with EN14103 standards. Specific energy analysis showed that cavitation-enhanced transesterification reduced energy consumption and peak temperature compared to traditional methods. The SPR’s capacity to induce high shear and localized turbulence under controlled cavitation offers a promising pathway for low-energy, scalable biodiesel production. Full article
(This article belongs to the Section B: Energy and Environment)
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22 pages, 6829 KiB  
Article
An Investigation of the Promotion of the Aerodynamic Performance of a Supersonic Compressor Cascade Using a Local Negative-Curvature Ramp
by Yongzhen Liu, Zhen Fan, Weiwei Cui, Qiang Zhou and Jianzhong Xu
Appl. Sci. 2025, 15(10), 5664; https://doi.org/10.3390/app15105664 - 19 May 2025
Viewed by 433
Abstract
Shockwaves induce considerable flow separation loss; it is essential to reduce this using the flow control method. In this manuscript, a method for suppressing flow separation in turbomachinery through a constant adverse-pressure gradient was investigated. The first-passage shock was split into a compression [...] Read more.
Shockwaves induce considerable flow separation loss; it is essential to reduce this using the flow control method. In this manuscript, a method for suppressing flow separation in turbomachinery through a constant adverse-pressure gradient was investigated. The first-passage shock was split into a compression wave system of the vane suction surface. The aim of this was to reduce loss from shockwave/boundary layer interactions (SWBLIs). This method promotes the performance parameters of the supersonic compressor cascade. The investigation targets were a baseline cascade and the improved system. Both cascades were numerically studied with the aid of the Reynolds-averaged Navier–Stokes (RANS) method. The simulation results of the baseline cascade were also validated through experimentation, and a further physical flow analysis of the two cascades was conducted. The results show that the first-passage shockwave was a foot above the initial suction surface, with a weaker incident shock along with a clustering of the compression wave corresponding to the modified cascade. It was also concluded that the first-passage shockwave foot of the baseline cascade was replaced with a weak incident shock, and a series of compression waves emanated from the adopted negative-curvature profile. The shock-induced boundary layer separation bubble disappeared, and much smaller boundary layer shape factors over the SWBLI region were obtained for the improved cascade compared to the baseline cascade. This improvement led to a high level of stability in the boundary layer state. Sensitivity analyses were performed through different simulations on both cascades, unveiling that the loss in total pressure was lower in the case of the updated cascade as compared to the baseline. Full article
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28 pages, 11453 KiB  
Article
Risk Analysis of Fuel Leakage and Explosion in LNG-Powered Ship Cabin Based on Computational Fluid Dynamics
by Yuechao Zhao, Yubo Li, Weijie Li, Yuan Gao, Qifei Wang and Dihao Ai
Fire 2025, 8(5), 192; https://doi.org/10.3390/fire8050192 - 10 May 2025
Cited by 1 | Viewed by 853
Abstract
In order to analyze the explosion risk of the engine room, this paper uses CFD software to simulate the LNG leakage process in the engine room of the ship, and uses the combustible gas cloud obtained from the leakage simulation to simulate the [...] Read more.
In order to analyze the explosion risk of the engine room, this paper uses CFD software to simulate the LNG leakage process in the engine room of the ship, and uses the combustible gas cloud obtained from the leakage simulation to simulate the explosion, analyzing its combustion and explosion dynamics. On the basis of previous studies, this paper studies the coupling of leakage and explosion simulation to ensure that it conforms to the real situation. At the same time, taking explosion overpressure, explosion temperature, and the mass fraction of combustion products as the breakthrough point, this paper studies the harm of explosion to human body and the influence of ignition source location on the propagation characteristics of LNG explosion shock wave in the engine room, and discusses the influence of obstacles on gas diffusion and accumulation. The results show that the LNG leakage reaches the maximum concentration in the injection direction, and the obstacles in the cabin have a significant effect on the diffusion and accumulation of gas. In the explosion simulation based on the leakage results, it can be determined that the shape of the pressure field generated by the explosion is irregular, and the pressure field at the obstacle side has obvious accumulation. Finally, in order to reduce the explosion hazard, the collaborative strategy of modular layout, directional ventilation, and gas detection is proposed, which provides ideas for the explosion-proof design of the cabin. Full article
(This article belongs to the Special Issue Confined Space Fire Safety and Alternative Fuel Fire Safety)
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16 pages, 3084 KiB  
Article
Effects of Combining Shockwaves or Radiofrequency with Aerobic Exercise on Subcutaneous Adipose Tissue and Lipid Mobilization: A Randomized Controlled Trial
by Leila Marques, Joana Neves, Ana Pereira, Ana Santiago, Sara Troia, Rui Vilarinho, Maria Manuela Amorim and Andreia Noites
Obesities 2025, 5(2), 31; https://doi.org/10.3390/obesities5020031 - 1 May 2025
Viewed by 1156
Abstract
Reducing abdominal subcutaneous fat is a common concern among women, with evidence suggesting that combining aerobic exercise with external shock waves or radiofrequency may enhance fat reduction. This study aimed to assess the effects of six sessions of external shock wave therapy or [...] Read more.
Reducing abdominal subcutaneous fat is a common concern among women, with evidence suggesting that combining aerobic exercise with external shock waves or radiofrequency may enhance fat reduction. This study aimed to assess the effects of six sessions of external shock wave therapy or radiofrequency combined with an aerobic exercise program on abdominal subcutaneous fat and lipid mobilization, compared to the effects of an aerobic exercise program alone. Thirty-one women (aged 18–60) were randomly assigned to three groups: EG1 (shockwave therapy + aerobic exercise), EG2 (radiofrequency + aerobic exercise), and CG (aerobic exercise only). Body composition measures, mean temperature, adipose tissue thickness, lipid profile, and glycerol and interleukin-6 levels were assessed before and after intervention. A significant decrease in the EG groups compared to the CG was observed in the subcutaneous abdominal thickness (p < 0.001, effect size of η2p = 0.446) and waist–hip ratio (p ≤ 0.001, effect size of η2p = 0.408). No significant changes were verified in the levels of lipolytic activity, lipid profile, and interleukine-6. Six sessions of shockwave or radiofrequency therapy combined with aerobic exercise reduced subcutaneous fat thickness and improved hip–waist ratio more effectively than aerobic exercise alone, without affecting lipid mobilization by changes in lipid profile, lipolytic activity, or interleukin-6 levels. Full article
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