Search Results (646)

Corrosion of reinforcing steel and degradation of concrete caused by chloride penetration are the most critical forms of durability failure in marine environments. This requires that repair materials possess both high impermeability and stable chemical binding capacity. In this study, the impact patterns of sulfoaluminate cement (SAC) dosage on the chloride erosion durability of an OPC-GGBS-SAC ternary repair system were systematically evaluated. Through chloride ion binding capacity tests, electrical flux experiments, and microscopic analytical techniques including XRD, DTG and SEM-EDS, the synergistic regulation mechanisms of the dual functions of ‘physical barrier’ and ‘chemical binding’ in the composite material were elucidated. The findings show that the performance of the composite material was optimal at an SAC content of 10%. The electrical flux of composite materials at 28 d was 28.9% lower than that of the OPC system, whilst the chloride ion binding rate increased by 3.92%. Microstructural analysis indicates that an appropriate amount of SAC promoted the generation of ettringite (AFt) to optimize the early-age pore structure and stimulated the production of more C-S-H gel and AFm phases, thus synergistically enhancing impermeability and chemical binding capacity. When the SAC content exceeded 10%, excess gypsum inhibited the formation of AFm. Moreover, the concentration of early-stage hydration led to microdefects, resulting in a decline in durability. This study identifies the optimal dosage of SAC in the ternary system and clarifies the underlying mechanism, thereby providing a scientific basis for designing high-durability repair materials suitable for harsh ocean conditions. Full article

Thermal–gas–chemical treatment (TGCT) using activated aluminum alloys is a promising near-wellbore stimulation method for high-viscosity oil reservoirs, combining localized heat generation, hydrogen release, pressure increase, and chemical activation of the treated zone. This study evaluates the potential of TGCT for the Karazhanbas field using laboratory core flooding experiments and reservoir-scale scenario analysis. Experiments were conducted on unconsolidated core models saturated with high-viscosity oil. Treatment with activated aluminum alloy and formation water generated up to 2600 mL of gas but did not increase oil displacement efficiency. In contrast, the system containing activated aluminum alloy, 3 wt.% HCl, and 2 wt.% surfactant intensified the reaction, promoted gas–liquid foam formation, increased electrical resistivity to 5000 Ω·m, and improved oil displacement efficiency from 0.37 to 0.61. The additional oil recovery reached 16.8 mL, corresponding to a relative increase of approximately 65%. Reservoir-scale scenario calculations showed a heterogeneous production response, with maximum oil production rate increases ranging from 0.03 to 3.27 m³/day, depending on well conditions. The results indicate that TGCT efficiency is controlled by the combined thermal, gas, and chemical effects rather than gas generation alone. Field-scale implementation requires the calibration of the treatment radius, effect duration, temperature response, gas saturation, permeability alteration, and well-specific reservoir conditions. Full article

The proliferation of daphnids in secondary clarifiers of urban wastewater treatment plants (WWTPs) can compromise effluent quality and disrupt treatment stability. This study evaluated the effectiveness of sodium hypochlorite (NaOCl) for controlling daphnid populations and assessed its influence on dormant eggs hatching. A pilot-scale oxidation ditch activated sludge system was operated under conditions simulating a full-scale WWTP. Acute toxicity tests were performed in clarified water (CW) and mixed liquor (ML) using NaOCl concentrations between 0.76 and 5 mg L⁻¹, with mortality monitored over 96 h and LC₅₀ values determined. In CW, concentrations ≥ 3.125 mg L⁻¹ caused 100% mortality within 24 h (24 h LC₅₀ = 1.75 mg L⁻¹). In ML, toxicity was significantly reduced (24 h LC₅₀ = 7.43 mg L⁻¹). Statistical analysis confirmed NaOCl concentration as the main driver of mortality, with additional contributions from operational parameters such as electrical conductivity, total dissolved solids, and dissolved oxygen. Hatching assays revealed that higher NaOCl concentrations and prior cold exposure (4 °C) increased ephippia hatching, reaching 40% under combined conditions. Although NaOCl effectively inhibits active organisms, it may stimulate dormant egg hatching, potentially sustaining populations. Optimized control strategies are therefore required to ensure effective and sustainable daphnid management in WWTPs. Full article

The increasing global demand for freshwater, together with the high energy consumption and environmental footprint of conventional desalination technologies, has stimulated growing interest in interfacial solar steam generation (ISSG). ISSG is a solar-driven water purification strategy that localizes heat at the air–water evaporation interface, thereby promoting surface evaporation without heating the entire bulk water body. The development of efficient, durable, and multifunctional ISSG systems depends strongly on substrate materials that can regulate water transport, heat localization, vapor release, and mechanical stability. This review focuses on cellulose-based substrates for ISSG and examines how their molecular structure, fibrillar assembly, and macroscopic porous architecture influence evaporation behavior and device function. The reviewed cellulose platforms are classified into three major groups: bottom–up assembled nanocellulose substrates, including cellulose nanocrystals, cellulose nanofibers, and bacterial cellulose; natural hierarchical substrates, including wood, cotton fabrics, and agricultural residues; and commercial planar substrates, including cellulose paper and membranes. Beyond evaporation performance, this review discusses multifunctional design strategies for salt regulation, antifouling and antibacterial operation, water–electricity cogeneration, and photocatalytic pollutant degradation, with emphasis on their mechanisms and functional trade-offs. Finally, we identify critical bottlenecks limiting practical deployment and propose a roadmap for future intelligent, adaptive, and multi-energy-coupled cellulose-based ISSG systems. These systems offer a promising platform for distributed and resource-efficient water treatment, but their practical and environmental benefits depend on fabrication energy, material safety, device lifetime, and end-of-life management. Full article

Background: The Forward Lunge is a representative squash-specific footwork movement involving rapid acceleration, braking, postural stabilization, and return propulsion. This study examined whether pre-competition neuromuscular electrical stimulation (NMES) combined with weighted squats was associated with differences in Forward Lunge performance and neuromuscular control in squash athletes. Methods: Thirty-six male squash athletes were randomly assigned to three groups: Weighted Squats, Fake Stimulation, and Real Stimulation, with 12 participants in each group. After the assigned acute intervention, all participants completed the squash-specific star test. Completion time was recorded using a Microgate Witty photocell timing system, while surface electromyographic (sEMG) signals from 14 right-side muscles were collected using a Delsys Trigno wireless electromyography system. High-speed video was used to identify the Forward Lunge movement cycle, and transistor–transistor logic (TTL) synchronization enabled temporal alignment among timing, video, and sEMG signals. Normalized root mean square (RMS), muscle co-activation index (CI), and non-negative matrix factorization (NMF)-based muscle synergy parameters were calculated. Between-group differences were analyzed using one-way analysis of variance (ANOVA) with Bonferroni post hoc comparisons, and false discovery rate (FDR) correction was applied to secondary neuromuscular outcomes. Results: Star test completion time differed significantly among the three groups (F = 28.65, p < 0.001, η² = 0.63). The Real Stimulation group showed a shorter completion time (10.35 ± 0.45 s) than the Weighted Squats group (11.80 ± 0.55 s) and Fake Stimulation group (11.55 ± 0.50 s). During the Forward Lunge movement cycle, normalized RMS values of the rectus abdominis (ABS; F = 18.56, p < 0.001, η² = 0.55) and latissimus dorsi (LD; F = 13.42, p < 0.001, η² = 0.44) were significantly higher in the Real Stimulation group. The gluteus maximus–biceps femoris (GLM–BF) co-activation index also differed significantly among groups (F = 58.42, p < 0.001, η² = 0.78), with higher values in the Real Stimulation group. Muscle synergy analysis showed group differences in selected muscle activation weights and temporal activation parameters. Conclusions: In this parallel-group acute intervention study based on post-intervention measurements, real NMES combined with weighted squats was associated with shorter star test completion time and altered neuromuscular control during the Forward Lunge movement cycle. The integrated use of photocell timing, wireless sEMG, high-speed video, and TTL synchronization provided temporally aligned sensor-based evidence for evaluating acute pre-competition activation strategies. However, due to the absence of baseline measurements, the findings should be interpreted as post-intervention between-group differences rather than definitive evidence of individual improvement. Full article

The long-term stability of dental implants is limited by multiple factors, including peri-implant infection, impaired osseointegration, and poor soft tissue sealing. Compared with conventional passive surface modification strategies, piezoelectric materials can convert mechanical energy into local electrical signals under occlusal loading, cell traction, or ultrasonic stimulation. With the aid of defect engineering, heterostructure construction, and co-catalytic design, these materials can also induce the generation of reactive oxygen species and reactive nitrogen species, thereby enabling on-demand antibacterial activity. This review systematically summarizes the bioelectric basis of bone tissue and clarifies how piezoelectricity and piezocatalysis may be used in dental implant surface engineering. Their applications are discussed in terms of antibiofilm and antibacterial activity, osteogenesis and osseointegration, osteoimmunomodulation, soft tissue healing, and temporally programmed therapy. In addition, this review also discusses issues that remain unresolved, such as polymer-based composite systems, realistic activation windows, evaluation standards, device–material integration, and multi-omics validation. Overall, piezoelectric surface engineering is evolving from a single osteogenesis-oriented strategy into an integrated platform that coordinates infection control, immune remodeling, and osseointegration. However, the actual effectiveness of its clinical application still needs to be determined through more rigorous mechanism analysis, long-term stability assessment, biosafety assessment, and standardized preclinical research. Full article

Objective: Rapid vertical manoeuvres and intermittent vibration in autonomous electric vertical take-off and landing (eVTOL) aircraft can provoke pronounced psychological anxiety in passengers. To address this, we propose a closed-loop adaptive system that integrates an in-ear wearable sensor with dynamic regulation of the cabin microenvironment, enabling real-time monitoring of each passenger’s autonomic state and delivering individualised mitigation through a continuous sense–analyse–intervene–feedback loop. Methods: The system is built around a pair of custom in-ear modules that integrate dual-wavelength photoplethysmography (PPG; 525 nm green and 940 nm infrared), galvanic skin response (GSR), and a six-axis inertial measurement unit (IMU) sampled at 200 Hz. To suppress the 20–80 Hz vibration generated by the distributed electric propulsion system, a compliant silicone damping sleeve attenuates high-frequency components at the hardware level, while a Kalman filter fuses the IMU and PPG streams and an adaptive notch filter removes residual rotor harmonics. The pipeline raises the heart-rate-variability (HRV) signal-to-noise ratio (SNR) to 24.1 dB, with a Pearson correlation of 0.96 against a medical-grade chest strap. A hybrid CNN–LSTM network—two convolutional layers (32 filters each) followed by two LSTM layers (128 hidden units)—predicts impending anxiety from HRV time-domain features (RMSSD, pNN50) and frequency-domain features (LF/HF ratio), triggering intervention 8.2 s in advance on average. According to the predicted anxiety level (mild/moderate/severe), a fuzzy controller modulates transcutaneous auricular vagus nerve stimulation (1–5 mA), the binaural-beat frequency (4–8 Hz, theta band), and the cabin lighting colour temperature (2700–6500 K) in real time. The intervention parameters are continuously refined by SPSA-based stochastic optimisation of the HRV recovery rate (step size 0.01; updated every 30 s). Results: In a randomised controlled experiment conducted in a simulated flight environment (N = 50; aged 22–45 years; 1:1 sex ratio), the active group reached physiological recovery in 52.3 s on average, compared with 98.6 s for the sham-controlled group—a 47% reduction (Cohen’s d = 1.24, p < 0.001). User acceptance reached 94%. Conclusions: The proposed in-ear platform enables closed-loop adaptive regulation of anxiety in the eVTOL cabin and overcomes the limitations of conventional passive mitigation strategies. By combining vibration-tolerant physiological sensing with multimodal environmental control, the work offers a practical pathway for improving passenger experience in urban air mobility and provides a useful reference for human-factors standards governing autonomous aircraft. Full article

This is a narrative review that explores the development of non-implantable vestibular devices designed to address postural instability, particularly in aging populations and patients with vestibular hypofunction. It establishes that balance relies on complex sensory integration and that the functional decline of this system creates a significant medical need. Three principal technological strategies are examined: sensory substitution devices, galvanic vestibular stimulation (GVS), and immersive visual feedback systems. Sensory substitution devices, which convert balance data into auditory, tactile, or electrotactile cues, demonstrate significant promise. Examples like vibrotactile belts provide feedback that reduces postural sway, enhancing stability and patient confidence. Parallel to this, GVS—using electrical currents applied to the mastoids—emerges as a potent non-invasive method to modulate vestibular pathways, improving balance control and even inducing neuroplastic changes, especially with stochastic “noisy” signals. The most recently developed devices include augmented and virtual reality technologies that offer innovative visual feedback, creating enriched rehabilitation environments that accelerate recovery by promoting sensory reweighting and neural adaptation. This review concludes that while implantable prostheses are advancing, non-invasive devices offer versatile, affordable, and complementary solutions for balance restoration. The future success of non-invasive alternatives hinges on developing more sophisticated stimulation protocols that account for the complexity of natural movement and individual patient contexts, expanding therapeutic options for vestibular disorders. Full article

Electrotactile feedback is a compact approach for providing tactile cues in robotic teleoperation, but personalized calibration remains time-consuming because tactile perception varies across users. To address this problem, this study develops a subject-informed multi-layer finite element model of fingertip electric-field distribution coupled with a neural-response model and proposes a simulation-derived configuration-ranking method termed the Perceived Correctness Score (PCS). A gradient boosting regression model is then used to recommend among 36 candidate electrode diameter–spacing combinations. Validation was conducted using a custom-developed 3 × 2 multi-channel fingertip electrotactile stimulation system in a shape/area recognition task involving six healthy subjects. The predicted PCS showed a moderate positive correlation with the measured mean recognition accuracy across configurations (Pearson r = 0.48, p < 0.05). The model achieved Top-1 exact matching for three of six subjects and Top-5 coverage for five of six subjects. Compared with conventional exhaustive psychophysical calibration, the proposed method reduced the average configuration time from 122.7 min to 16.0 min, corresponding to an efficiency improvement of 87.0%. These results show that model-guided ranking can substantially reduce the burden of individualized electrotactile configuration. Full article

Background/Objectives: Ankle–foot orthoses (AFOs) are commonly used to improve gait in children with cerebral palsy (CP), but their effect on specific gait patterns is underreported. This study evaluates the utilization of the Gait Pattern Classification System for Children with Spastic CP (GaP-CP) to investigate the effects of ankle–foot orthoses on gait kinematics, spatio-temporal parameters and the energy cost of walking. Methods: In this retrospective study, 66 ambulatory children with spastic CP underwent 3D gait analysis with and without AFOs or functional electrical stimulation. Gait patterns were classified according to GaP-CP. AFOs were articulated, flexible, or rigid. Thirty-six children also performed a 5 min walk test with gas exchange measurements. Step length, walking speed, and the energy cost of walking were calculated. Gait kinematics were analyzed with statistical nonparametric mapping. Non-parametric statistics were used to investigate orthotic effects for the total group and for each gait pattern. Results: Ankle kinematics improved in swing phase and initial contact (10 degrees less plantarflexion, p < 0.05) for the total group, dropfoot and genu recurvatum. During the stance phase, reduced knee extension in genu recurvatum (by 3 degrees, p < 0.05) and increased knee extension in crouch (by 3 degrees, p < 0.05) were observed. Median changes in non-dimensional step length were clinically significant (>0.039, p ≤ 0.02, effect size ≥ 0.55) for the total group and the dropfoot, genu recurvatum, and crouch subgroups, while changes in most gait indices, walking speed and the energy cost of walking were not clinically significant. Conclusions: The combined use of GaP-CP and kinematic analysis provided new insights into the effects of ankle–foot orthoses on gait. Articulated and flexible orthoses may not have provided adequate support for genu recurvatum and crouch gait, showing a potential value in gait pattern specific orthotic design to optimize gait kinematics. Full article

Flexible electrolyte-gated synaptic field-effect transistors (EGFETs) have emerged as a promising platform for neuromorphic visual systems, owing to their low-voltage operation, diverse synaptic plasticity, and exceptional mechanical flexibility. In particular, gel-based electrolytes, including hydrogels and ion gels, play a pivotal role as functional gate dielectrics, enabling efficient ion transport and strong ion–electron coupling through electric double-layer (EDL) formation. By leveraging these unique properties at the semiconductor/gel interface, EGFETs can effectively emulate essential biological synaptic behaviors, including short-term and long-term plasticity under optical stimulation. The inherent compatibility of EGFETs with a broad range of semiconductor channels, gel electrolytes, and flexible substrates enables the development of wearable and conformable neuromorphic platforms that seamlessly integrate sensing, memory, and signal processing within a single device architecture. Recent advances in gel material engineering, such as polymer network design, ionic modulation, and nanofiller incorporation, have significantly improved ion transport dynamics, interfacial stability, and device performance. Despite remaining challenges related to ion migration stability, multi-physical field coupling, and large-area device uniformity, these developments have substantially advanced the practical potential of gel-based systems. This review provides a comprehensive overview of the operating mechanisms, gel-based material systems, synaptic functionalities, mechanical reliability, and future prospects of flexible electrolyte-gated visual synapses, highlighting their considerable potential for next-generation intelligent perception and artificial vision technologies. Full article

Background: Electrochemotherapy enhances the intracellular delivery of anticancer agents through electroporation but is traditionally limited to cytotoxic drugs associated with significant side effects. Vitamin C (ascorbic acid) exhibits selective anticancer activity when accumulated at high intracellular concentrations; however, its therapeutic application is restricted by poor membrane permeability and rapid systemic clearance. Methods: In this study, we investigated whether reversible electroporation, applied using a custom-designed variable plate electrode system designed to deliver a uniform electric field, could potentiate the antitumor efficacy of low-dose vitamin C. Numerical simulations were performed to optimize electrode spacing and stimulation voltage, suggesting homogeneous electric field coverage throughout the tumor volume. The proposed approach was evaluated in vitro using MDA-MB-231 and 4T1 breast cancer cell lines and in vivo in a 4T1 murine breast cancer model. Results: Low-dose vitamin C alone produced minimal cytotoxic effects, whereas its combination with electroporation significantly reduced cell viability and increased apoptotic and necrotic cell death in vitro. In vivo, vitamin C–assisted electrochemotherapy resulted in pronounced tumor growth suppression, with tumor volumes reduced to approximately 0.34-fold of baseline by day 15, accompanied by decreased proliferation and marked tissue disruption. Conclusions: These findings demonstrate that uniform-field reversible electroporation markedly enhances the intracellular delivery and antitumor activity of low-dose vitamin C, supporting this technology-driven strategy as a promising, low-toxicity alternative to conventional chemotherapeutic agents in electrochemotherapy for solid tumors. Full article

Objectives: This study aimed to demonstrate the feasibility of a novel wireless energy-transmitting implantable diaphragm pacemaker for restoring respiratory ventilation. Methods: The diaphragm pacing (DP) system was designed based on the principle of electromagnetic resonance coupling. The safety of device implantation was analyzed through finite-element simulations of multi-field coupling between electromagnetic heating and biological tissue. In vitro testing with coils embedded in pork demonstrated the system output characteristics. This device was used in miniature Bama pigs that underwent deep anesthesia and respiratory arrest (N = 8). Respiratory airflow, diaphragmatic displacement, and blood gases were used to evaluate the effectiveness of the designed DP system. Results: Thermal effect simulation results show that the temperature rise of the surrounding tissue does not exceed 2 °C during 1 h of transmission power (0.5–1.3 W) operation of the receiver. In vitro tests with two receivers embedded in pork showed that the DP system can effectively output stimulation waveforms over a certain transmission distance (5–35 mm). The stimulation waveform output by the receiver is consistent with the parameters set by the external controller. In phrenic nerve electrical stimulation experiments, the peak respiratory airflow and tidal volume remained stable over 50 consecutive respiratory cycles. The tidal volume (108.63 mL) and diaphragmatic displacement (0.883–2.15 cm) in a pig induced by DP demonstrate the effectiveness of respiratory ventilation. The arterial blood gas analysis results and temperature rise experiment during implantation further confirmed the effectiveness and safety of the ventilation. Conclusions: The implantable diaphragmatic pacemaker developed in this study exhibits good thermal safety, stable output, and effective respiratory ventilation. A control group with commercial diaphragmatic pacemakers and data from chronic implantation experiments are needed to further evaluate its effectiveness. Full article

Weak alternating electric fields are widely used in neuromodulation techniques such as transcranial alternating current stimulation (tACS), yet the precise biophysical mechanisms underlying neuronal responses remain incompletely understood. Current computational models often neglect the electrical properties of the extracellular microenvironment, limiting their predictive accuracy. Motivated by experimentally observed frequency-dependent modulation of neuronal activity, we developed a two-compartment model of hippocampal CA3 pyramidal neurons in which extracellular resistance is explicitly parameterized and systematically examined as a key factor influencing neuronal response properties under external electric fields. Within a dual-compartment Hodgkin–Huxley framework, the neuron is divided into a “soma–basal dendrite unit” and an “apical dendrite unit,” accounting for voltage polarization induced by external fields. Using phase-locking ratio curves and three-dimensional parameter response surface, we systematically characterized neuronal sensitivity to field parameters and examined how potassium equilibrium potential ($V_K$) and extracellular resistance ($R_{\mathrm{out}}$) modulate these responses. Our results demonstrate that increasing $R_{\mathrm{out}}$ enhances neuronal responsiveness to external fields, while $V_K$ variations primarily regulate intrinsic excitability. These findings provide mechanistic insights into the frequency-dependent modulation of neuronal responses under weak electric fields, consistent with phenomena observed in biological neural systems, and provide a mechanistic and theoretical framework for understanding the joint effects of electric field amplitude and frequency on neuronal sensitivity to weak electric fields, which may help inform future neuromodulation strategies. Full article

Background/Objectives: The renin–angiotensin–aldosterone (RAA) system is a key regulator of cardiovascular homeostasis. Recent evidence suggests that Angiotensin II (Ang II) can trigger ferroptosis, an iron-dependent form of cell death. We previously demonstrated that periodontitis induces neurovascular dysfunction, and our preliminary observations indicate that this oral inflammatory model is associated with elevated blood pressure. However, the mechanism by which Ang II impaired nitrergic vasodilation and triggered ferroptosis in cerebral arteries remains unclear. This study investigates the functional effects of electrical and chemical nerve stimulation in adult spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY). Methods: Endothelium-denuded basilar arterial (BA) rings from SHRs and WKYs were used to assess the impact of Ang II on neurogenic relaxation via wire myography. Results: Vascular relaxation responses to nicotine and transmural nerve stimulation (TNS) were significantly diminished in SHRs compared to WKYs. This impairment was reversed by both acute preincubation and chronic treatment with losartan (an AT1 receptor antagonist). In WKY BAs, exogenous Ang II pretreatment inhibited relaxation responses to nicotine, TNS, and isoproterenol. Importantly, this inhibition was effectively reversed by marimastat (MMP inhibitor), catalase (antioxidant), and ferrostatin-1 (ferroptosis inhibitor). Conclusions: Our findings indicate that Ang II induces functional alterations in neurovascular signaling patterns by triggering ferroptosis within nerve terminals. This process leads to a functional imbalance between sympathetic and parasympathetic influences, ultimately impairing neurogenic nitrergic dilation in the BAs of SHRs. These results suggest that targeting Ang II-induced ferroptosis may alleviate the neuroinflammation and cognitive decline associated with hypertension-related cerebrovascular dysfunction. Full article