Search Results (169)

This study investigates ultrasonic wave propagation in carbon fiber reinforced polymer (CFRP) composites containing foreign object debris (FOD) by introducing a novel method to characterize the depth and size of FOD, from a single captured waveform generated by an out-of-focus spherically focused transducer. Current methods of inspection utilize a raster approach to both detect and quantify FOD, which is limited to identifying FOD smaller than 4 mm. The method introduced in the present paper allows for a single point scan to detect and quantify FOD, as small as 0.5 mm, with the highest error in the depth estimation being less than 8%. This paper presents experimental testing to inform a finite element analysis of a full waveform simulation of an immersion tank inspection environment and compares waveforms between testing and simulation. A transient pressure acoustic model is developed in the COMSOL Multiphysics environment to simulate wave propagations. Simulation results provide waveform reflection and transmission at material interfaces, which will occur when there is an acoustic mismatch between materials. The transmitted ultrasonic wave is partially reflected toward the transducer upon encountering material interfaces between the water, CFRP laminate, and the FOD. Simulation results show that the acoustic profile and pressure of the reflected wave captured by the transducer allows an accurate identification of FOD depth and size within the composite structure, suggesting an alternative method of inspection to quantify FOD characteristics faster than through conventional approaches. Results show an increase in captured signal pressure of over 125% between the 0.5 mm FOD and the 1 mm FOD located on the mid-plane of the laminate, and 500% between the same 0.5 mm FOD and 1 mm FOD placed near the front wall. These results suggest the potential sensitivity limits for physical component. This work demonstrates that small FOD, which are often difficult to resolve and quantify under conventional raster-based inspection, can be reliably identified by intentionally positioning the specimen within the defocused region of a spherically focused transducer. Results are presented to correlate the reflected acoustic pressure amplitude to defect depth, transducer–specimen distance, and FOD size, providing an approach to quantitatively discriminate small defects that would otherwise produce ambiguous signals. Full article

The use of ships and boats as sea-state (SS) measurement platforms has the potential to expand ocean observations while providing actionable information for real-time operational decision-making at sea. Within the framework of the Wave Buoy Analogy (WBA), this work develops an inverse approach in which efficient simulations of wave-induced motions of an advancing vessel are used to train a neural network (NN) to predict SS parameters across a broad range of wave climates. We show that a reduced set of novel motion discriminant variables (MDVs)—computed from short time series of heave, roll, and pitch motions measured by an onboard inertial measurement unit (IMU), together with the vessel’s forward speed—provides sufficient and robust information for accurate, near-real-time SS estimation. The methodology targets small, barge-like tugboats whose operations are SS-limited and whose motions can become large and strongly nonlinear near their upper operating limits. To accurately model such responses and generate training data, an efficient nonlinear time-domain seakeeping model is developed that includes nonlinear hydrostatic and viscous damping terms and explicitly accounts for forward-speed effects. The model is experimentally validated using a scaled physical model in laboratory wave-tank tests, demonstrating the necessity of these nonlinear contributions for this class of vessels. The validated model is then used to generate large, high-fidelity datasets for NN training. When applied to independent numerically simulated motion time series, the trained NN predicts SS parameters with errors typically below 5%, with slightly larger errors for SS directionality under relatively high measurement noise. Application to experimentally measured vessel motions yields similarly small errors, confirming the robustness and practical applicability of the proposed framework. In operational settings, the trained NN can be deployed onboard a tugboat and driven by IMU measurements to provide real-time SS estimates. While results are presented for a specific vessel, the methodology is general and readily transferable to other ship geometries given appropriate hydrodynamic coefficients. Full article

Crossland Tankers is a leading manufacturer of bulk-load road tankers in Northern Ireland. These tankers transport up to forty thousand litres of liquid over long distances across diverse road conditions. Liquid sloshing within the tank has a significant impact on driveability and the tanker’s lifespan. This study introduces a novel Multiphysics model combining Smooth Particle Hydrodynamics (SPH) and Finite Element Analysis (FEA) to simulate fluid–structure interactions in a full-scale road tanker, validated with real-world road test data. The model reveals high-stress zones under braking and turning, with peak stresses at critical chassis locations, offering design insights for weight reduction and enhanced safety. Results demonstrate the approach’s effectiveness in optimising tanker design, reducing prototyping costs, and improving longevity, providing a valuable computational tool for industry applications. Full article

Residues in the grain tank of seed-production wheat harvesters often cause varietal admixture, challenging seed purity maintenance above 99%. To address this, an intelligent cleaning system was developed for automatic residue recognition and removal. The system utilizes an RGB-D camera and an embedded AI unit paired with an improved lightweight object detection model. This model, enhanced for feature extraction and compressed via LAMP, was successfully deployed on a Jetson Nano, achieving 92.5% detection accuracy and 13.37 FPS for real-time 3D localization of impurities. A D–H kinematic model was established for the 4-DOF cleaning manipulator. By integrating the PSO and FWA models, the motion trajectory was optimized for time-optimality, reducing movement time from 9 s to 5.96 s. Furthermore, a gas–solid coupled simulation verified the separation capability of the cyclone-type dust extraction unit, which prevents motor damage and centralizes residue collection. Field tests confirmed the system’s comprehensive functionality, achieving an average cleaning rate of 92.6%. The proposed system successfully enables autonomous residue cleanup, effectively minimizing the risk of variety mixing and significantly improving the harvest purity and operational reliability of seed-production wheat. It presents a novel technological path for efficient seed production under the paradigm of smart agriculture. Full article

This paper presents a side-by-side study of CFD predictions and experimental measurements for a novel counter-flow heat exchanger installed in the sidewall of a dishwasher (HEBS). The work aims to improve appliance efficiency by transferring heat from discharged hot wastewater to the incoming cold supply. Motivated by sustainability goals and tightening EU energy rules, the research targets the high losses typical of conventional machines. This approach combines detailed ANSYS Fluent 2022R2 simulations with controlled laboratory tests on a bespoke test rig. The measured data show a repeatable rise in the cold-water temperature of roughly 8 K, corresponding to an approximate 15% gain in thermal performance for the heat-recovery stage. While the simulations and experiments efficiently agree based on trends and qualitative behavior, there are noticeable quantitative differences in the total energy transfer, indicating the models need further refinement. The validation carried out here forms a solid basis for design optimization and for reducing energy consumption in household dishwashers. This work overcomes the limitations of previous studies which typically rely on external storage tanks or static heat recovery analysis. The primary novelty of this paper lies in the empirical validation of a high-efficiency heat exchanger integrated into the extremely constrained sidewall volume of the appliance, tested under transient, on-the-fly flow conditions, providing a verified methodology for constrained industrial applications. Full article

Background/Objective: Serotonin and dopamine are key neurotransmitters involved in regulating mood, anxiety, and locomotor activity. Specific transporters mediate their reuptake, SERT and DAT, making them targets for drugs such as Fluoxetine and Methylphenidate. Zebrafish (Danio rerio), due to their genetic and neurochemical similarity to humans, serve as a valuable model for studying the behavioral effects of these drugs. This study aimed to compare the behavioral phenotypes induced by SERT and DAT blockers in adult zebrafish using the Novel Tank Diving Test (NTT), thereby generating a swimming profile for drugs acting on these monoamine transporters that can be utilized in drug discovery and behavior. Methods: Adult zebrafish were administered Fluoxetine or Methylphenidate and subjected to the NTT. Behavioral endpoints measured included bottom-dwelling time (anxiety-like behavior), swimming velocity (locomotor activity), and transitions to the upper zone (exploratory behavior). Results: Fluoxetine treatment significantly reduced bottom-dwelling behavior, increased transitions to the upper zone, and decreased erratic swimming, indicating reduced anxiety and enhanced exploration. In contrast, Methylphenidate administration led to prolonged bottom-dwelling and reduced exploration, suggesting increased anxiety-like behavior and decreased exploration. These findings highlight distinct behavioral profiles resulting from selective modulation of serotonergic and dopaminergic pathways. Conclusions: The study demonstrates that SERT and DAT blockades produce divergent behavioral effects in adult zebrafish, with Fluoxetine exhibiting anxiolytic and exploratory-promoting actions. At the same time, Methylphenidate induces anxiety-like and less exploratory behaviors. These results underscore the utility of zebrafish as a valuable translational model for neuropharmacological research and drug discovery, providing insights into the differential impact of serotonergic and dopaminergic modulation on behavior. Full article

This study examines the moderating effects of renewable and nuclear energy on the relationship
between transportation index (air and land) and environmental sustainability
from 1995 to 2022 across the top 27 polluting countries. The study employed a series
of pre-estimation tests, along with the novel Method of Moments Quantile Regression
(MMQR), to estimate heterogeneous effects across the lower, middle, and upper quantiles of
environmental sustainability. The MMQR results indicate that environmental sustainability
is hampered by transportation, whereas renewable and nuclear energy promote it. The
moderation effect model shows that both renewable and nuclear energy development mitigate
the negative environmental externality from the transportation sector. The controlling
factors, GDP and inflation, are found to be harmful for environmental sustainability, while
trade openness is found to be favourable. The robustness findings using Driscoll and Kray
standard errors (DKse) yielded similar results; nonetheless, the magnitude of the coefficient
varies substantially. Thus, think tanks and policymakers are recommended to integrate
renewable and nuclear energy into the transportation sector’s energy portfolio to mitigate
its negative environmental impacts. Full article

Anxiety-like behavior in fish is commonly assessed using non-invasive behavioral paradigms such as the Light/Dark preference, Novel Tank, and Open Field tests. In this study, we validated these three assays in rainbow trout (Oncorhynchus mykiss), a species of commercial relevance, to characterize their anxiety-related responses. To explore behavioral changes associated with feeding anticipation and satiety, we implemented a feeding schedule consisting of two daily meals and conducted behavioral tests at specific times before and after feeding. Trout exhibited clear patterns of scototaxis, geotaxis, and thigmotaxis, consistent with anxiety-like behavior described in other teleosts. Our results showed a significant increase in anxiety-like responses before feeding, coinciding with food anticipatory activity observed prior to expected feeding schedules, which diminished after food intake, as evidenced by each test individually. Moreover, multivariate analysis combining parameters from all three tests improved discrimination between anxious and relaxed fish. The behavioral states before and after feeding resembled anxiety-like and anxiolytic conditions reported in other species, supporting that food anticipatory activity reflects an anxious state in rainbow trout as well. These findings endorse using a multi-test behavioral battery to assess anxiety-like states and provide a framework for studying neurobiological mechanisms of emotional regulation related to feeding in teleosts. Full article

Silver nanoparticles (AgNPs) were synthesized using a modified literature method involving aqueous AgNO₃ (3 mM) and plant extract (LCE) at a constant ratio, under alkaline conditions and controlled temperature. The nanoparticles were characterized by UV-Vis spectroscopy, dynamic light scattering (DLS), zeta potential analysis and scanning transmission electron microscopy (STEM). The UV-Vis spectra displayed a broad absorption band around 450 nm, indicative of polydispersity, while DLS revealed a hydrodynamic diameter of 90.3 nm with a polydispersity index of 0.3366. Zeta potential values suggested reduced electrostatic stability compared with previously reported plant-derived AgNPs, although STEM images confirmed predominantly spherical, well-dispersed nanoparticles with sizes between 15 and 20 nm. Functional assays in zebrafish demonstrated the biological relevance of AgNPs. In scopolamine-induced models of cognitive and behavioral deficits, AgNPs treatment significantly improved memory and locomotor activity, as assessed by the Y-Maze, Novel Tank Diving Test and Novel Object Recognition Test. Full article

The overexploitation of wild populations for the marine ornamental trade necessitates optimized captive breeding, particularly for iconic species like the clownfish Amphiprion ocellaris. This study investigated the social behavior and cognitive abilities of juvenile clownfish in relation to artificial rearing practices. Using modified three-tank tests, we assessed social preference and cognition ability in two size groups: Small-bodied Group (SG: 2.0–2.5 cm) and Large-bodied Group (LG: 3.5–4 cm). The results indicated that clownfish have the following: (a) Strong Social Preference: Both SG and LG exhibited significant preference for areas near conspecifics (SPI > 0), with SG showing significantly higher SPI values than LG. (b) Developmental Stage Differences: SG demonstrated a stronger tendency to cluster tightly near conspecifics. LG showed wider exploration patterns and greater movement. (c) Cognition Ability: SG showed renewed interest towards a novel fish after habituation to a familiar fish, while LG displayed a stronger preference for the familiar fish. These findings suggest that clownfish juveniles possess advanced sociality and basic cognition ability. Furthermore, the observed shift in social interaction preference with developmental stages informs optimal timing for grading practices to minimize artificial rearing stress. This study provides some behavioral insights for optimizing large-scale artificial rearing protocols for clownfish, reducing pressure on wild populations. Full article

This study investigates the neuroprotective and anxiolytic effects of Solanum macrocarpon L. leaf n-butanol extract (SMB) in a zebrafish model of scopolamine (SCOP; 100 μM)-induced cognitive and behavioral impairments. SCOP, a muscarinic receptor antagonist, is commonly used to mimic memory deficits and anxiety-like behaviors associated with neurodegenerative conditions. Zebrafish were chronically exposed to SMB at concentrations of 1, 3, and 6 mg/L. Behavioral assessments included anxiety-related paradigms, such as novel tank diving (NTT), novel approach (NA), and light–dark transition (LD) tests, as well as cognitive assays, including the Y-maze and novel object recognition (NOR) tests. SMB significantly mitigated SCOP-induced anxiety-like behaviors and cognitive deficits in a dose-dependent manner. Biochemical analyses demonstrated that SMB inhibited acetylcholinesterase (AChE) overactivity, indicating restoration of cholinergic function. Furthermore, SMB enhanced the activity of endogenous antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) and significantly reduced oxidative stress biomarkers, including malondialdehyde (MDA) and protein carbonyls. These findings suggest that SMB may exert neuroprotective effects through modulation of cholinergic signaling and oxidative stress. Overall, SMB represents a promising phytotherapeutic candidate for mitigating cognitive and anxiety-related symptoms linked to oxidative damage. Further investigations are warranted to characterize its active constituents and assess long-term efficacy and safety in models of neurodegeneration. Full article

Hydrogen serves as a key clean-energy carrier, with the main hurdles lying in safe, efficient transport and storage (gas or liquid) and in end-use energy conversion. Liquid hydrogen (LH), as a high-density method of storage and transportation, presents cryogenic insulation as its key technical issues. In LH storage tanks, the performance of high vacuum multilayer insulation (HVMLI) will decline due to hydrogen release and leakage from the microscopic pores of steel, which significantly destroy the vacuum layer. The accumulation of residual gases will accelerate thermal failure, shorten the service life of storage tanks and increase safety risks. Adsorption is the most effective strategy for removing residual gases. This review aims to elucidate materials, methods, and design approaches related to hydrogen storage. First, it summarizes adsorbents used in liquid hydrogen storage tanks, including cryogenic adsorbents, metal oxides, zeolite molecular sieves, and non-volatile compounds. Second, it explores experimental testing methods and applications of hydrogen adsorbents in storage tanks, analyzing key challenges faced in practical applications and corresponding countermeasures. Finally, it proposes research prospects for exploring novel adsorbents and developing integrated systems. Full article

Background/Objectives: Scopolamine (SCO) is widely employed as a pharmacological model of anxiety and amnesia in both rodents and zebrafish, the latter representing a valuable translational model in neuropsychopharmacology. The present study aimed to evaluate the neuroprotective and antioxidant potential of chronic administration of an ethanolic extract from Calendula officinalis flowers (CEE). Methods: Adult zebrafish (n = 10/group, both sexes) were exposed to CEE at concentrations of 1, 3, and 10 mg/L, administered daily for 22 consecutive days. After the initial 7-day pretreatment period, fish were challenged with SCO (100 μM, immersion for 30 min) followed by behavioral testing, including the Novel Tank Diving Test, Light/Dark Test, Novel Approach Test, Y-Maze, and Novel Object Recognition. Subsequently, brain homogenates were analyzed for acetylcholinesterase (AChE) activity, antioxidant enzymes (superoxide dismutase—SOD, catalase—CAT, glutathione peroxidase—GPx), reduced glutathione (GSH), protein carbonyls, and malondialdehyde (MDA). Results: Chronic CEE administration significantly attenuated scopolamine-induced anxiety-like behaviors and improved spatial memory (Y-maze) and recognition memory (NOR), as well as reduced anxiety-like behavior in the SCO-induced zebrafish model. Biochemical analyses revealed that CEE restored AChE activity, enhanced the activity of SOD, CAT, and GPx, and increased GSH levels, while concomitantly reducing protein oxidation and lipid peroxidation. The most pronounced effects were observed at 3 mg/L, which nearly normalized both behavioral and biochemical parameters. Conclusions: The CEE exerted anxiolytic and procognitive effects in zebrafish through combined cholinergic and antioxidant mechanisms. These findings highlight its translational potential as a promising candidate for the prevention and treatment of anxiety-related and cognitive disorders. Full article

Background: Bovine mastitis caused by Prototheca spp. is the most significant animal disease of algal origin, with an increasing number of cases reported worldwide. Currently, there is no effective treatment, so control requires the culling of infected animals. In Chile, information is limited, and a discrepancy remains in the literature regarding the Prototheca species involved in bovine mastitis. Methods: This study aimed to molecularly type and phenotypically characterize Prototheca isolates associated with bovine mastitis in Chile. Sixty-six Prototheca isolates obtained from individual bovine mastitis milk samples and bulk tank milk samples were analyzed through cytochrome b gene (cytb) sequencing, Random Amplified Polymorphic DNA–Polymerase Chain Reaction (RAPD-PCR) analysis, and phenotypic evaluation (morphology, antimicrobial susceptibility, and biofilm formation). Results: Sixty-five isolates were identified as P. bovis and one as P. ciferrii, marking the first report of the latter in bovine mastitis in Chile. RAPD analysis revealed a high genetic diversity in P. bovis. All strains exhibited resistance to the antibiotics tested from the Fluoroquinolone, β-lactam, and sulfonamide groups; however, 100% of the strains showed susceptibility to aminoglycosides, with gentamicin standing out as a potential therapeutic option. Most P. bovis strains formed weak (81.5%, 53/65) or moderate (15.4%, 10/65) biofilms, which could favor the persistence of infection. Conclusions: These findings provide novel insights into the molecular and phenotypic characteristics of Prototheca spp. in Chile, highlighting the predominance of P. bovis, the emergence of P. ciferri, and the implications for antimicrobial management and disease control. Full article

High peak-hour energy consumption from air conditioning in commercial buildings creates significant operational costs and grid instability. This study experimentally investigates the thermo-economic performance of a vapor compression refrigeration system (VCR) ice storage system to address this challenge through load shifting. The methodology involved operating a custom test rig, featuring an insulated test chamber and an ice tank with a novel spiral evaporator, under an improved 8 h night charging and 9 h day discharge strategy. Results show the system consumed 5.44 kWh of electricity to store 7.70 kWh of thermal energy, achieving a charging Coefficient of Performance (COP) of 1.42. A total of 5.195 kWh of cooling was delivered with a discharge efficiency of 67.5%. The experimental cost analysis confirmed an approximate 20% operating cost advantage over conventional direct cooling. A simple payback assessment indicates strong sensitivity to tariff structures and annual operating days. This study concludes that the optimized Ice Storage System (ISS) is a technically viable and economically advantageous solution for managing peak cooling loads, providing a validated reference model and dataset for future work. Full article