Wave Amplitude Research Articles

Dynamic responses of steep bedding slope-tunnel system under coupled rainfall-seismicity: Shaking table test

The coupling effects of rainfall, earthquake, and complex topographic and geological conditions complicate the dynamic responses and disasters of slope-tunnel systems. For this, the large-scale shaking table tests were carried out to explore the dynamic responses of steep bedding slope-tunnel system under the coupling effect of rainfall and earthquake. Results show that the slope surface and elevation amplification effect exhibit pronounced nonlinear change caused by the tunnel and weak interlayers. When seismic wave propagates to tunnels, the weak interlayers and rock intersecting areas present complex wave field distribution characteristics. The dynamic responses of the slope are influenced by the frequency, amplitude, and direction of seismic waves. The acceleration amplification coefficient initially rises and then falls as increasing seismic frequency, peaking at 20 Hz. Additionally, the seismic damage process of slope is categorized into elastic (2-3 m/s2), elastoplastic (4-5 m/s2) and plastic damage stages (≥ 6.5m/s2). In elastic stage, ΔMPGA (ratio of acceleration amplification factor) increases with increasing seismic intensity, without obvious strain distribution change. In plastic stage, ΔMPGA begins to gradually plummet, and the strain is mainly distributed in the damaged area. The modes of seismic damage in the slope-tunnel system are mainly of tensile failure of the weak interlayer, cracking failure of tunnel lining, formation of persistent cracks on the slope crest and waist, development and outward shearing of the sliding mass, and buckling failure at the slope foot under extrusion of the upper rock body. This study can serve as a reference for predicting the failure modes of tunnel-slope system in strong seismic regions.

The September 6, 2021 MW 5.4 Tofalaria earthquake at a weakly active segment of the Main Sayan fault (Eastern Siberia)

We study in detail the Mw 5.4 September 6, 2021 Tofalaria earthquake occurred in a mountain area of the Eastern Sayan which is characterized by a low level of seismic activity. An interest in the seismic event is caused, on the one hand, by poor knowledge about stress-strain field of the crust in the considered region, and, on the other hand, by its relation to the NW segment of the ancient Main Sayan fault – a structural boundary between the Sayan-Baikal fold belt and the tectonically stable Siberian platform. Seismic moment tensors and hypocentral depths of the mainshock and its largest aftershock (Mw 4.6) are inverted from intermediate-period surface wave amplitude spectra calculated at the stations located at teleseismic distances. Integral source parameters of the mainshock, characterizing its spatio-temporal development, are also estimated and the fault plane is determined. Epicenters of 31 aftershocks with M ≥ 1.8, occurred up to the end of 2021, are constrained from body waves recorded at regional seismic stations. The obtained results show that the Tofalaria earthquake occurred under the influence of the SW-NE compression, which is observed in Western Mongolia. Focal mechanism of the largest aftershock and the NE elongation of the aftershock epicentral field (22 km) indicate stress redistribution after the mainshock in a local crustal volume, bordered by small-scale faults.

Imaging Attenuation From Array Analysis of Surface Waves

AbstractAnelastic attenuation provides key insight in our understanding of thermal and rheological structures and the associated deformation and dynamic mechanisms of the Earth's deep interior. Unfortunately, attenuation tomography is advanced far behind wave‐speed tomography due to the challenge in properly excluding the complex effects of elastic heterogeneities on seismic wave amplitude. By taking advantage of phase tracking in seismic array analysis, here we derive a new theory of Helmholtz tomography that well accounts for attenuation, source radiation, and scattering, etc., and present a technique called Helmholtz Multi‐Event Tomography (HelMET) to retrieve the attenuation properly. The effectiveness of this method is then validated by synthetic inversions. Our synthetic seismograms are calculated using a newly developed three‐dimensional finite‐difference algorithm that accounts for physical dispersion and dissipation in anelastic media and remains accurate and stable even if strong attenuation exists. Compared to the traditional method poorly performed in the synthetic inversion, the HelMET well recovers the input attenuation anomalies, suggesting that this method can be used to successfully isolate attenuation from the complicated effects of elastic heterogeneities. Our results underline the implication of the new theory and method in accurately imaging high‐resolution attenuation structures and unambiguously interpreting the anelastic heterogeneities of the Earth by array‐based earthquake and ambient noise data with inexpensive computation.

Numerical study on the polarity change process during internal wave shoaling

Polarity change is an important mechanism for internal waves shoaling. In this study, a numerical model for simulating the real-scale internal wave passing over slope-shelf topography is established based on the Fourier pseudo-spectral method and weakly nonlinear theory. By numerical simulation, the effects of shelf height, initial wave amplitude, and inclination angle on the waveform characteristics and energy properties of the internal wave during its shoaling are investigated. In the polarity change process, the initial internal wave converts into a depression wave and a generated elevation wave behind it. The distance between the peak of the elevation wave and the trough of the depression wave is a key feature to describe the polarity change. In terms of energy properties, the energy ratio of depression and generated elevation waves compared with the initial wave as well as their relative magnitude is mainly determined by the shelf height. In addition, the initial wave amplitude also affects the generation of the elevation wave and the attenuation of the depression wave to a certain extent. The increase in the inclination angle hinders the formation of the elevation wave but has little effect on the depression wave energy.

Influence of corrugated jet plates on internal heat transfer and flow dynamics of double-wall cooling: experimental-numerical approach

In the present study, combined experimental and numerical investigations were carried out to analyze the fluid flow dynamics and heat transfer of impinging jets in a corrugated double-wall structure for exhaust nozzle cooling operating at high temperatures. The sinusoidal wavy plate, with multi-jet holes positioned at its trough, served as the jet plate, creating a staggered configuration with respect to the effusion holes. The transient thermochromic liquid crystal (TLC) method was employed to determine the local distribution of the Nusslet number on the flat effusion plate in a wind tunnel at small Reynolds numbers (ranging from 450 to 2700 based on the jet hole diameter (d)). In the numerical part of the study, the k-ω SST turbulence model verified with the TLC data was used to solve the RANS equations. The effects of jet-to-plate spacing (Have/d = 1.6–3.6), corrugated plate amplitude (A/d = 0.2–0.8), effusion hole diameter (de/d = 0.6–1.5), and Reynolds numbers were examined in detail. Our results showed that the introduction of the corrugated structure in the jet plate altered the high-velocity region pattern within the jet hole, leading to a 16 %-81 % reduction in jet core length compared to the flat jet plate. At a relatively high wave amplitude (A/d ≥ 0.5), the vortex structure underwent significant changes, inducing a higher level of turbulence kinetic energy in the near-wall region of the target chamber. This led to enhanced heat transfer near the stagnation and effusion hole regions compared to the flat double-wall cooling. The effusion hole diameter exerted a minimal effect on the overall Nusselt number of the corrugated double-wall cooling. At very low Reynolds numbers (Rej 〈900), the flow and heat transfer characteristics in corrugated double-wall cooling resembled those observed in flat double-wall cooling.

A model of thermodynamic stabilization of nanocrystalline grain boundaries in alloy systems

Nanocrystalline (NC) materials are intrinsically unstable against grain growth. Significant research efforts have been dedicated to suppressing the grain growth by solute segregation, including the pursuit of a special NC structure that minimizes the total free energy and completely eliminates the driving force for grain growth. This fully stabilized state has been predicted theoretically and by simulations but is yet to be confirmed experimentally. To better understand the nature of the full stabilization, we propose a simple two-dimensional model capturing the coupled processes of grain boundary (GB) migration and solute diffusion. Kinetic Monte Carlo simulations based on this model reproduce the fully stabilized polycrystalline state and link it to the condition of zero GB free energy. The simulations demonstrate the emergence of a fully stabilized state by the divergence of capillary wave amplitudes on planar GBs and by fragmentation of a large grain into a stable ensemble of smaller grains. The role of solute diffusion in the full stabilization is examined. Possible extensions of the model are discussed.

On the effect of wave amplitude and corrugation profile of certain types of corrugated channels on thermal performance and entropy generation

This study aims to examine experimentally and numerically the thermal-hydraulic performance and entropy generation of wavy channels: sinusoidal and triangular, and compare them with respect to the straight channel. Various wavy amplitudes and corrugation profiles are considered in a sinusoidal wavy channel and a triangular wavy channel and assessed with the straight channel. Experimental test rig is built and the experiments are carried out on laminar air flow and used to verify the simulation results. The main findings show that the HT rate, fluid flow, and entropy generation are affected by the corrugation profile and wave amplitude of the wavy channel. The maximum Nusselt number of 11.17 occurred in a sinusoidal wavy channel with a wave amplitude equal to 1.75, and high friction factor also happens in this model. It was found that the sinusoidal and triangular wavy channels with A = 0.75 and a flow rate range of 1–1.75 have the highest overall thermal performance factor. Also, the total entropy generation of the straight channel was lower than all corrugated channel models. In conclusion, it has been found that the best compromise between enhanced HT and the accompanying increase in both pressure drop and entropy generation is occurred in case of A = 0.75 at flow rate ranged from 1 to 1.67 LPM.

The effect of performance contingent reward prospects flexibly adapts to more versus less specific task goals.

In some situations, for example, when we expect to gain a reward in case of good performance, goal-driven top-down attention is particularly strong. Little is known about the task specificity of such increases of top-down attention due to environmental factors. To understand to what extent performance-contingent reward prospects can result in specific and unspecific changes in cognitive processing, we here investigate reward effects under different levels of task specification. Thirty-two participants performed a visual or an auditory discrimination task cued by two consecutive visual stimuli: First, a reward cue indicated if good performance was rewarded. Second, a task cue announced either which of the two tasks would follow (precise cue) or that both tasks would follow equally likely (imprecise cue). Reward and task cue preciseness both significantly improved performance. Moreover, the response time difference between precisely and imprecisely cued trials was significantly stronger in rewarded than in unrewarded trials. These effects were reflected in event-related potential (ERP) slow wave amplitudes: Reward and preciseness both significantly enhanced the contingent negative variation (CNV) prior to the task stimulus. In an early CNV time interval, both factors also showed an interaction. A negative slow wave prior to the task cue was also significantly enhanced for rewarded trials. This effect correlated with the reward difference in response times. These results indicate that reward prospects trigger task-specific changes in preparatory top-down attention which can flexibly adapt over time and across different task requirements. This highlights that a reward-induced increase of cognitive control can occur on different specificity levels.

Ultrasound enabled simultaneous measurement of coating wear depth and lubricant film thickness in a sliding bearing

Sliding bearings, serving as critical supporting components in rotating machinery, often work by riding on an ultra-thin oil film. The rupture of this oil film can cause wear of the soft coating on the bearing and even lead to catastrophic failures. This paper introduces a novel ultrasonic reflection-based approach to simultaneously measure both lubricant film thickness and coating wear depth. Through an analysis of the ultrasonic wave propagation in a worn bearing, it is observed that the echo waveform remains independent of wear depth but correlates with changes in the time of flight back to the transducer. Given this, the captured time or phase shift between the reflected and incident waves, together with the reduction in the wave amplitude, enables a simultaneous calculation of both oil film thickness and coating wear depth. The efficacy of the proposed method is validated through acoustic simulations and experiments with varied coating roughness.

Nonlinear pendulum metamaterial to realize an ultra-low-frequency field effect bandgap

A field effect transistor (FET) is an extensively employed component in large-scale integrated circuits to regulate circuit on or off by modulating its gate voltage. The mechanical counterpart of a FET is of great significance for advanced regulations of acoustic or elastic waves. Recently proposed active metamaterials are promising scenarios of FET based on the opening and closing of frequency bandgaps through active elements, but hindered by the structural complexity in practice. In this study, we propose and experimentally realize a nonlinear pendulum metamaterial (NPMM) as a mechanical ultra-low-frequency FET. By employing the perturbation method to investigate its dispersion relationship, we show that the NPMM possess a field effect bandgap. Namely, the bandgap can be opened or closed by controlling the excitation amplitude of the impinging wave, which is largely affected by the relative mass of the inner pendulum unit. As a verification, the transmission behavior of the NPMM is numerically studied and experimentally tested. It shows that, once the amplitude of the impinging wave exceeds a certain threshold, the disappearance of a bandgap will be observed with a sudden amplification of the output wave. The central frequency of the field effect bandgap is as low as 4 Hz, whereas the characteristic size of the unit cell is only 4 cm. We expect that the present work opens a new avenue for low-frequency wave regulation.

Prediction of amplitude of fault generated travelling wave in medium-voltage grids for fault type classification

This paper proposes a new solution for the classification of short-circuits in medium-voltage distribution grids. The solution requires the measurements of the phase voltages at the time of the short-circuit and the voltage amplitudes of the short-circuit wave resulting from the fault. The values of the voltage before the short-circuit are used to calculate the expected values of the short-circuit wave amplitudes for the different types of short circuits. These calculations are based on an analysis of the charge flow between the capacitances of the power line due to the disturbance. The short-time matrix pencil method was used to detect the incoming short-circuit waves. Tests of the algorithm were carried out on the IEEE 34-bus Feeder model, taking into account the influence of voltage sensors on the measured signal values. The classification algorithm uses only non-zero components due to their relatively low attenuation. Despite that, it achieves high performance in the classification of single- and two-phase short-circuits.

Sustainable removal of pigment dye from traditional batik textile wastewater using ZnO photocatalysis

Wastewater management in the textile industry poses significant challenges, especially for small-scale facilities lacking proper treatment systems. As an alternative solution, in-situ wastewater treatment has gained prominence. Presently, solar-driven photocatalytic materials offer a promising avenue for effective wastewater remediation. This study employed a one-step probe ultrasonication method to synthesize ZnO nanoparticles with exceptional photocatalytic properties. Comprehensive optimization was undertaken to achieve ZnO particles with superior photocatalytic performance. The effects of various parameters, including wave amplitude (ranging from 0 to 80 %), ultrasonication time (from 0 to 45 min), and precursor zinc acetate concentration (between 0.1 to 0.3 M), were thoroughly investigated. By carefully controlling these conditions, non-agglomerated ZnO particles significantly improved photocatalytic activity, especially under visible-light conditions, when treating wastewater from the textile industry. The produce particle at 0.1 M in conjunction with maximum ultrasonication time and amplitude, provide more dispersed particle with smaller particle sizes. The photocatalytic process exhibited remarkable efficiency, with up to 98 % of the textile waste degraded within 60 min of reaction time using the ZnO particle produced under this condition. Moreover, this higher photocatalytic activity was supported by the rate of kinetic constant of 0.0365 min⁻¹, representing the pseudo-first-order kinetic. Furthermore, this research highlights the robust reusability of ZnO as a photocatalytic material, which remained stable even after three consecutive cycles. These findings affirm that ZnO particles synthesized through the probe ultrasonication method hold great potential for treating dye-containing textile effluents, providing a sustainable and effective solution for addressing this environmental concern.

Study of effects of perforation layouts on wave energy dissipation caused by a submerged perforated breakwater in front of a vertical seawall

Perforated structures are a promising alternative to traditional breakwaters for constructing harbors and protecting coastlines. Perforated structures can effectively remove wave energy from ocean waves by the energy dissipation associated with the turbulence generated by the flow through the perforations in the structure. Understanding the factors that may affect the hydrodynamic characteristics of flow through a perforated plate is important for designing perforated marine structures. The purpose of this research was to determine the wave energy dissipation performance of thin-walled plates with various perforation configurations using OpenFOAM-based CFD simulation. Ten different plate configurations were designed and tested with a constant porosity while varying the distribution, shape, and size of the perforations, to determine the impacts to energy dissipation performance. The energy dissipation was quantified by CFD simulations of wave-interaction with a submerged perforated plate placed vertically in front of a vertical backwall (“seawall”). Physical wave flume experiments were also conducted to verify and validate the numerical models. The results showed that the perforation distribution, shape, and size play a minimal role in the energy dissipation performance when porosity is held constant. The minimal performance deviation between the perforation configurations was consistent across a range of wave periods and amplitudes.

Moth-wing-inspired metasurface for modulating sound amplitude and phase

Moth wings are multifunctional bio-composite structures serve varied purposes, including sound absorption and flight. Inspired by this, we propose a metasurface for reflective acoustic wave modulation. The metasurface features periodically arranged resonant elements, consisting of perforated plates and resonant cavities, mimicking moth wing scales. The hinged connection between the resonant elements and the background structure allows for precise and wide-range tuning of sound amplitude and phase, and enables deployment on irregular surfaces. We present three detailed metasurface designs, showcasing various structural parameters to demonstrate their quantitative manipulation of sound amplitude and phase, both individually and simultaneously. In addition to conventional energy absorption and path manipulation functions, the metasurface also highlights several striking features, including wavefront tailoring and reflection shunting, as demonstrated through numerical simulations. This study offers novel insights into the precise control of wave amplitude and phase over diverse scales and terrains, whilst also presenting a practical implementation in the field of acoustics.

Impaired cognitive flexibility in major depressive disorder: Evidences from spatial-temporal ERPs analysis

BackgroundMajor Depressive Disorder (MDD) may exhibit impairments in cognitive flexibility. This study investigated whether the cognitive flexibility deficits in MDD are evident across general stimuli or specific to emotional stimuli, while exploring the underlying neuropsychological mechanism. MethodsA total of 41 MDD patients and 42 healthy controls (HCs) were recruited. Event-related potentials (ERPs) were recorded when participants performed a non-emotional and an emotional task switching paradigm (N-ETSP and ETSP), both of which assessed cognitive flexibility. Microstate and source localization analysis were applied to reflect brain activity among different brain areas during task switching. ResultsIn the N-ETSP, MDD group showed larger P3 difference wave (Pd3) amplitudes and longer P2 difference wave (Pd2) latencies. In the ETSP, MDD group displayed smaller N2 difference wave (Nd2) amplitudes and larger Pd3 amplitudes. The comparison of sLORETA images of emotional switch task and emotional repeat task showed that MDD group had increased activation in the precentral gyrus in microstate2 of the P2 time window and had reduced activation in the middle occipital gyrus in microstate3 of the N2 time window. LimitationsThe cross-sectional design failed to capture dynamic changes in cognitive flexibility in MDD. ConclusionsMDD demonstrated impaired cognitive flexibility respond to both non-emotional and emotional stimuli, with greater impairment for negative emotional stimuli. These deficits are evident in abnormal ERPs component during the early attention stage and the later task preparation stage. Furthermore, abnormal emotional switching cost in MDD appears to be related to early abnormal perceptual control in the parietal-occipital cortex.

Central Actions of Leptin Induce an Atrophic Pattern and Improves Heart Function in Lean Normoleptinemic Rats via PPARβ/δ Activation.

Leptin, acting centrally or peripherally, has complex effects on cardiac remodeling and heart function. We previously reported that central leptin exerts an anti-hypertrophic effect in the heart via cardiac PPARβ/δ activation. Here, we assessed the impact of central leptin administration and PPARβ/δ inhibition on cardiac function. Various cardiac properties, including QRS duration, R wave amplitude, heart rate (HR), ejection fraction (EF), end-diastolic left ventricular mass (EDLVM), end-diastolic volume (EDV), and cardiac output (CO) were analyzed. Central leptin infusion increased cardiac PPARβ/δ protein content and decreased HR, QRS duration, and R wave amplitude. These changes induced by central leptin suggested a decrease in the ventricular wall growth, which was confirmed by MRI. In fact, the EDLVM was reduced by central leptin while increased in rats co-treated with leptin and GSK0660, a selective antagonist of PPARβ/δ activity. In summary, central leptin plays a dual role in cardiac health, potentially leading to ventricular atrophy and improving heart function when PPARβ/δ signaling is intact. The protective effects of leptin are lost by PPARβ/δ inhibition, underscoring the importance of this pathway. These findings highlight the therapeutic potential of targeting leptin and PPARβ/δ pathways to combat cardiac alterations and heart failure, particularly in the context of obesity.

Defect Solutions of the Nonreciprocal Cahn-Hilliard Model: Spirals and Targets.

We study the defect solutions of the nonreciprocal Cahn-Hilliard model. We find two kinds of defects, spirals with unit magnitude topological charge, and topologically neutral targets. These defects generate radially outward traveling waves and thus break the parity and time-reversal symmetry. For a given strength of nonreciprocity, spirals and targets with unique asymptotic wave number and amplitude are selected. We use large-scale simulations to show that at low nonreciprocity α, disordered states evolve into quasistationary spiral networks. With increasing α, we observe networks composed primarily of targets. Beyond a critical threshold α_{c}, a disorder-order transition from defect networks to traveling waves emerges. The transition is marked by a sharp rise in the global polar order.

Cloud-Edge Motion by a Ducted Gravity Wave

Cloud-Edge Motion by a Ducted Gravity Wave

Revolutionizing bioconvection: Artificial intelligence-powered nano-encapsulation with oxytactic microorganisms

Using incompressible smoothed particle hydrodynamics (ISPH), this study examines the bioconvection flow of oxytactic microorganisms in a porous annulus populated by nano-encapsulated phase change material (NEPCM). Artificial neural network (ANN) is joined with the ISPH method to accurately predict the values of average Nu‾. Between the outside hexagonal-shaped domain and the embedded wavy cylinder, a new annulus is produced. The ranges of the pertinent parameters are wave amplitude of an embedded cylinder A=0.1−0.5, Hartmann number Ha=0−80, a radius of the cylinder Rcyld=0.05−0.5, Darcy number Da=10−2−10−5, undulation number Kund=2−32, bioconvection Rayleigh number Rab=1−1000, Rayleigh number Ra=103−106, and Lewis number Le=1−20. The regulated geometric characteristics of an embedded wavy cylinder, such as wavy amplitude, cylinder radius, and undulation numbers, have been found to contribute significantly to widening the cooling region and minimizing the oxytactic microorganisms. Hence, the embedded wavy cylinder can be applied for various thermal uses including cooling devices and heat exchangers. The average Nu‾ is enhanced under an increment in the geometric parameters of the embedded cylinder. Increasing Rayleigh/bioconvection Rayleigh numbers enhances the buoyancy forces that accelerate the velocity field.

MicroRNA-based engineered mesenchymal stem cell extracellular vesicles to treat visual deficits after blast-induced trauma

Our previous studies have shown the benefit of intravitreal injection of a mesenchymal stem cell (MSC)- derived secretome to treat visual deficits in a mild traumatic brain injury (mTBI) mouse model. In this study, we have addressed whether MSC-derived extracellular vesicles (EV) overexpressing miR424, which particularly targets neuroinflammation, show similar benefits in the mTBI model. Adult C57BL/6 mice were subjected to a 50-psi air pulse on the left side, overlying the forebrain, resulting in mTBI. Sham-blast mice were controls. Within an hour of blast injury, 3 μl (∼7.5 × 108 particles) of miR424-EVs, native-EVs, or saline was delivered intravitreally. One month later, retinal morphology was observed through optical coherence tomography (OCT); visual function was assessed using optokinetic nystagmus (OKN) and electroretinogram (ERG), followed by immunohistological analysis. A separate study in adult mice tested the dose-response of EVs for safety. Blast injury mice with saline showed decreased visual acuity compared with the sham group (0.30 ± 0.03 vs. 0.39 ± 0.01 c/d, p < 0.02), improved with miR424-EVs (0.39 ± 0.02 c/d, p < 0.01) but not native-EVs (0.33 ± 0.04 c/d, p > 0.05). Contrast sensitivity thresholds of blast mice receiving saline increased compared with the sham group (85.3 ± 5.9 vs. 19.9 ± 4.8, %, p < 0.001), rescued by miR424-EVs (23.6 ± 7.3 %, p < 0.001) and native-EVs (45.6 ± 10.7 %, p < 0.01). Blast injury decreased “b” wave amplitude compared to sham mice (94.6 ± 24.0 vs. 279.2 ± 25.3 μV, p < 0.001), improved with miR424-EVs (173.0 ± 27.2 μV, p < 0.03) and native-EVs (230.2 ± 37.2 μV, p < 0.01) with a similar decrease in a-wave amplitude in blast mice improved with both miR424-EVs and native-EVs. Immunohistology showed increased GFAP and IBA1 in blast mice with saline compared with sham (GFAP: 11.9 ± 1.49 vs. 9.1 ± 0.8, mean intensity/100,000 μm2 area, p < 0.03; IBA1: 36.08 ± 4.3 vs. 24.0 ± 1.54, mean intensity/100,000 μm2 area, p < 0.01), with no changes with native-EVs (GFAP: 12.6 ± 0.79, p > 0.05; IBA1: 32.8 ± 2.9, p > 0.05), and miR424-EV (GFAP: 13.14 ± 0.76, p > 0.05; IBA1: 31.4 ± 2.7, p > 0.05). Both native-EVs and miR424-EVs exhibited vitreous aggregation, as evidenced by particulates in the vitreous by OCT, and increased vascular structures, as evidenced by αSMA and CD31 immunostainings. The number of capillary lumens in the ganglion cell layer increased with increased particles in the eye, with native EVs showing the worst effects. In conclusion, our study highlights the promise of EV-based therapies for treating visual dysfunction caused by mTBI, with miR424-EVs showing particularly strong neuroprotective benefits. Both miR424-EVs and native-EVs provided similar protection, but issues with EV aggregation and astrogliosis or microglial/macrophage activation at the current dosage call for improved delivery methods and dosage adjustments. Future research should investigate the mechanisms behind EVs' effects and optimize miR424 delivery strategies to enhance therapeutic outcomes and reduce complications.