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Background and objective: After vestibular schwannoma (VS) surgery, some patients exhibit different degrees of peripheral facial paralysis, which can seriously affect their quality of life. The recovery of facial nerve function after surgery typically takes a considerable amount of time; therefore, the recovery of facial nerve function depends mainly on the rehabilitation treatment and nursing after discharge. In the past, we implemented conventional paralysis rehabilitation nursing program for patients with facial paralysis due to VS surgery. However, several patients with facial paralysis have bad compliance and do not achieve ideal facial nerve function recovery. Therefore, this study aimed to investigate whether modified facial paralysis rehabilitation nursing improves the effectiveness of rehabilitation of facial paralysis after VS surgery by analysing the clinical data of patients. Methods: We screened the patients with facial paralysis after VS surgery from December 2019 to May 2023. The patients were divided into the conventional and modified groups based on the different nursing programs (conventional vs. modified facial paralysis rehabilitation nursing program) to compare the differences in facial nerve function, quality of life of patients, and compliance of rehabilitation between the two groups. Results: We analysed 128 patients with facial paralysis after VS surgery who met the inclusion and exclusion criteria; 65 and 63 patients in the conventional and modified group, respectively. The number of patients in the modified group with House–Brackmann grade changes >0 in facial nerve function was significantly higher than that in the conventional group 3 months after surgery (82.5 % vs 63.1 %, p = 0.01). Except for the lacrimal control score, the mean scores of the Chinese version of the FaCE scale were significantly higher in the modified group than those in the conventional group at 1 and 3 months postoperatively. Conclusions: The modified facial paralysis rehabilitation nursing, i.e., integrated use of facial expressive muscle exercises and facial massage with video-assisted education, substantially improved the facial nerve function, quality of life, and compliance of rehabilitation nursing of patients with facial paralysis after VS surgery.

Cotton is the most popular fabric used in human clothing and garment, and its joining process is still based on the traditional sewing method. In this study, a new approach to cotton fabric joining via UV-laser induced polymerisation was investigated, which involved preparation of a silane coupling agent (3-Aminopropyl) triethoxysilane (3-Aps) for surface modification of cotton fabric, and formulation and application of a silica-sol photosensitive resin as the filler. The developed resin consists of two other silanes, Silane A174 and KH560 so as to provide chemical bonds with the cellulose of cotton surface and the 3-Aps modified cotton. The results showed that the silica-sol resin not only produced self-polymerisation due to photothermal effect, but also joined with the fiber surfaces by chemical bonding, which enhanced the surface interaction with cotton fibers and obtained excellent mechanical properties. The heat accumulation at joint was detected in real-time using the infrared thermography, which ensured the fast drying and curing of the silica-sol containing resin. With 4 % silica-sol content in resin, the interfacial bonding was optimal for APS-Fabric, and the tensile force of the 2 mm joint reached 300 N exceeding the ultimate breaking strength of the cotton fabric itself. The fabric joint was demonstrated to withstand at least 20 washing cycles without cracking. This new fabric joining technique provides both strong bonding and sufficient flexibility in the joints, resulting in high strength and durable cotton fabric joining, which has a broad application prospect in the field of apparel.

Mg alloy, as a promising lightweight structural material, finds applications in various fields. However, poor surface properties like wear resistance greatly limit its applications. As a surface modification technology, ultrasonic shot peening (USP) has gained significant popularity. In this study, temperature-assisted USP (TA-USP) was firstly applied to AZ31 Mg alloy. The influence of peening duration and temperature on microstructural evolution and mechanical properties was investigated in details. The ball-on-disk dry sliding wear test was performed to examine the tribological behavior. The results show that a gradient microstructure and surface nanocrystallization are introduced by TA-USP. The gradient becomes significantly pronounced as the peening duration extends. The surface hardness increases from the as-annealed 60.9 ± 1.8 HV to 159.0 ± 6.1 HV after processed at room temperature with 800 s, and a depth of about 600 μm for the affected region is achieved. When the peening temperature is raised, the gradient weakens, even disappears at 300 °C, and the hardness decreases. Notably, the gradient microstructure and enhanced hardness exhibit significant thermal stability below 200 °C. The wear curves and morphology analysis suggest that TA-USP obviously improves wear resistance. The surface nanocrystalline results in an easy formation of MgO patches and reduces the coefficient of friction. Moreover, the presence of gradient microstructure also retards the delamination phenomenon. Increasing peening duration or temperature to a moderate level will lead to an enhanced wear resistance, owing to its dependence on both hardness and toughness. A simplified wear transition map is roughly established to predict optimum wear resistance.

Compared with traditional laser shock peening by nanosecond pulse laser, femtosecond laser shock peening (FLSP) exhibits superior flexibility and efficiency since it can be carried out directly in air without any ablative or confinement layers. In this work, FLSP was successfully performed on AZ31 magnesium alloy sheet. The influence of pulse energy on surface morphology and roughness, microstructure, surface residual stress and hardness was investigated in details. The results show that varying the laser pulse energy could effectively improve the surface integrity of the material. Regular dents are produced at the material surface with relatively low pulse energies, and the regular dent morphology disappears gradually with increasing pulse energy, suggesting an increased surface roughness. Surface microhardness and residual compressive stress are increased significantly after FLSP. The surface microhardness increases from the untreated 58.13 HV to the maximum value of about 69.58 HV at 37 μJ, by an increase of 19.7%. At 73 μJ, the residual compressive stress rises to a maximum value of approximately 59.6 MPa from an untreated 16.3 MPa. Moreover, the nano-hardness near the surface at the cross section is 1.68 GPa at 37 μJ, with an increase of 46% compared to the untreated 1.14 GPa. Particularly, twins and grain refinement layers are observed near the surface after FLSP, also indicated by the XRD analysis. The plastic deformation and grain refinement with low pulse energies contribute to the surface strengthening while the thermal effect and surface oxidation with increasing pulse energy may inhibit the enhancement of surface integrity.

The invasion of pathogens derived from diet or the environment triggers intestinal inflammation, which is a result of the host intestinal barrier damage and immune dysfunction, such as the decrease of host defense peptides (HDPs) and inhibition of cell proliferation. Herein, the siRNA interference demonstrated that a critical lysozyme, which was mainly induced by dietary supplementations of sodium butyrate and forskolin, improved cell proliferation by inhibiting p38 MAPK and JNK signaling pathways and reinforced the intestinal barrier. Moreover, we established a mouse model of intestinal inflammation with Citrobacter rodentium (C. rodentium). It was found that NaBu and FSK stimulated intestinal epithelial proliferation to repair barrier damage, and performed stronger disease resistance to C. rodentium infection on account of the lysozyme upregulation in colon. Therefore, this study revealed that NaBu and FSK prevented or alleviated the development of foodborne infections by promoting lysozyme expression, which may be mediated by the effect of lysozyme on promoting cell proliferation and improving barrier function.

Laser machining of sapphire faces challenges due to the low laser beam energy absorption. A silicon (Si) plate contacting the rear surface of the sapphire substrate was used as an absorptive material to improve the laser absorption and affect material removal from the rear surface. A near-infrared laser with a wavelength of 1030 nm and pulse duration of 2 ns was focused at the interface, causing Si ablation and generation of a plasma plume with immense recoil pressure. The proposed approach for sapphire machining via enhanced laser absorption at the Si-sapphire interface is illustrated, and a probable material removal mechanism is discussed. Effects of processing parameters on machining depth and surface roughness were investigated using Taguchi L27 orthogonal array design and analysis of variance (ANOVA). It is found that repetition rate has the most significant effect on the machining performance characteristics, among other parameters. Furthermore, a multi-objective optimization was performed to optimize the process by integrating the Taguchi method with Grey Relational Analysis (GRA). The maximum machined depth of 59.1 μm and the minimum surface roughness of 0.145 μm were obtained by conducting confirmation tests at the optimal settings. The optimal processing parameters were obtained corresponding to the repetition rate of 1000 kHz, laser fluence of 1.2 J/cm2, hatching distance of 0.01 mm, scanning speed of 1000 mm/s, and single pass. The integrated Taguchi and GRA methodology offers an alternative for optimizing laser machining processes.

Two passes of constrained groove pressing (CGP) were conducted on a two-phase Mg–Li alloy followed by temperature-assisted ultrasonic shot peening (TA-USP) with different peening durations and temperatures. The effects of TA-USP and CGP on microstructural evolution and mechanical properties were investigated in details. Surface gradient microstructure including nanocrystalline and partial amorphization is introduced by TA-USP. Grain refinement is more significant with longer durations and lower temperatures. Pretreatment by CGP before TA-USP introduces fine and homogeneous microstructure in the alloy due to severe plastic deformation. The average grain sizes of α-Mg and β-Li are refined from the as-annealed 31.6 μm and 12.9 μm to 2.5 μm and 2.2 μm, respectively. The depth of USP-affected region increases with the increase of peening duration and temperature, and a depth of about 300 μm is achieved by direct TA-USP at room temperature with 400 s. The microstructure gradient is reduced at elevated temperatures. The hardness and strength increase while the ductility decreases with the increase of peening duration. The decrease in hardness with the increase of peening temperature is more significant than peening duration. Compared with direct TA-USP, pretreatment by CGP before TA-USP can obviously enhance the surface strengthening. When processed by TA-USP at 200 °C with 100 s, the tensile strength and yield strength increase from 141.9 MPa and 106.2 MPa to 158.3 MPa and 134.7 MPa, respectively. The elongation to failure decreases from 29.1% to an acceptable value of about 16.1%.

Water-based coatings are gradually replacing traditional oil-based coatings for environmentally friendly applications, which creates a new paradigm in corrosion control of metallic components. In this work, water-based ZrO2–SiO2 sol-gel coatings were prepared for corrosion protection of carbon steel. The effects of the sol-gel ZrO2 to SiO2 ratio, coating thickness, corrosion inhibitor content and surface hydrophobicity on the coating physicochemical and anti-corrosion properties were investigated. The results showed that, compared to the pure silica coating, coating with 1/9 wt% ZrO2 in SiO2 matrix and coating thickness of 25 μm provided about 7 times higher corrosion resistance (impedance modulus 1.38 × 108 Ω cm2). A smart-releasing corrosion inhibitor containing Ce3+ ions (0.91 wt%) loaded into the layered structure of bentonite showed ability to delay the corrosion of substrate by 9 orders of magnitude by trapping Cl− ions from the environment and releasing Ce3+ ions at the cracked substrate surface. By applying a hydrophobic top layer, the water contact angle increased from 89° to 115°, which further increased the impedance modulus of the coating from 2.42 × 109 to 3.60 × 109 Ω cm2. The optimized coating passed salt spray standard corrosion test for 720 h (on scribed coating) due to the cathodic protection by corrosion inhibitor and shielding effects of a top hydrophobic layer. This work provides an enhanced strategy of dual-functional anti-corrosion coatings with surface water repellency and internal smart-releasing corrosion inhibitor for steel against environmental corrosion and damages with efficient self-healing functionality.

Piezoelectric polyvinylidene fluoride (PVDF) based piezoelectric materials are good candidates for energy harvesting devices and sensing systems. Improving the piezoelectric sensitivity of the electro-spun PVDF fibers is still challenging and highly desirable. In this work, ZnO@Ag nanoparticles were synthesized and utilized as surface modifier to generate a hierarchical structure on the fiber surfaces to construct a flexible and piezoelectric three-phase coupling sensor. The effects of the atomic ratio of Ag:ZnO, surface morphology and particle concentration of ZnO@Ag nanoparticles on the β-phase content, piezoelectricity, wettability and mechanical stability of the sensor device were systematically investigated. The elastic modulus of ZnO@Ag/PVDF membrane is 0.01322 GPa, which is close to that of human skin 0.0188 GPa. Due to synergistic effect of the enhanced electrostatic field polarization and surface hierarchical structure, the ZnO@Ag/PVDF piezoelectricity sensor possessed voltage and current outputs of 15.0 Vpp and 1.775 μA respectively, which were 3.5 and 5.4 times higher than pure PVDF-based sensor. The sensitivity of the ZnO@Ag/PVDF nanofiber-based sensor was 2.422 V/kPa, which was 14.4 times higher than that of pure PVDF-based sensor. The sensor has a fast response/recovery time of 30/45 ms. The sensor can accurately detect various physiological strain signals such as cantilever oscillatory excitation, finger press, or walking behavior, and can light-up several light-emitting diodes (LEDs) and charge a capacitor (20 μF) in a short period (2.41 V in 5 Sec). This fiber-based energy harvesting and pressure sensor demonstrates promising applications in self-powered flexible wearable electronic devices in healthcare and home-care fields.

We report a method to fabricate micro-pore arrays on a copper sheet by a 355 nm UV nanosecond pulse laser, and investigate the effects of surface microstructures and micro-pore spacing on the wettability of the formed copper micro-mesh. We found that the surface was initially hydrophilic, but changed to superhydrophobic-oleophilic with water contact angle 151° and oil contact angle about 10° after exposed to ambient environment for 14 days. We analysed the surface morphologies of the processed samples with a three-dimensional profilometer, measured the water and oil contact angles, and characterized the surface by a field emission environmental scanning electron microscope (FESEM) and energy dispersive X-ray spectrometer (EDS). The surface chemistry changes were confirmed by X-ray photographic spectroscopy (XPS). Effective oil-water separation performance of the fabricated copper mesh was demonstrated. Learning from the natural change, we designed a coating material containing C8 long C–C (H) chain and coated onto the freshly prepared copper mesh to convert the surface property into a preferred superhydrophobic-oleophilic nature. This study provides a controllable methodology consisting laser processing and surface modification for making micro-pore copper mesh as a simple and effective method for oil-water separation.

In this study, a picosecond (ps) laser was employed to produce micro-textures on ductile iron in linearly processing leading to significantly higher processing efficiency. The fabrication efficiency was increased about 1331 times as compared to the more common spot-by-spot texturing method. The ps laser induced graphene (LIG) structures were simultaneously fabricated in dimples, which further enhanced the surface tribological properties. The surface micro-textures were produced by forming micro-dimples on the substrate via the laser ablation process. The dimple diameter and area density were regulated by varying the key laser processing parameters, and were experimentally correlated to the tribological properties of the ductile iron substrate. To understand deeper into the wear reduction mechanism of the micro-dimples, simulation models based on the Reynold equation were established, which analyze the flow field pressure distribution and demonstrate the hydrodynamic lubrication effect of the micro-textures. The ball-on disk friction test showed that the area density of the micro-textures had a significant influence on the friction and wear properties. The micro-texture with the area density of 20% and the average dimple diameter of 36 μm showed the highest volume wear rate reduction of 70% and the friction coefficient reduction of 20% respectively. The results indicated that the simultaneous laser in-situ generation of graphene micro-textures is an effective way of enhancing tribological properties on the ductile iron surface. It enhances the hardness of textured surfaces, thermal diffusion, debris capture ability, and fluid dynamic lubrication effect.

Picosecond fiber laser was subjected on surface of ductile cast iron to induce graphene-like micro-texture array and enhance the tribological properties. The size of the dimples was regulated in the range of 5 μm–110 μm. The in-situ fabrication process was carried out on the workpiece surface in parallel manner and the scanning speed can be up to 3 m/s. The formation mechanism of graphene-like structure was analyzed. The tribological properties of the textured samples were investigated using a ball-on-disk tribometer. The results showed that the laser textured samples exhibit low coefficient of friction and the anti-wear properties were improved significantly. The textured sample showed no distinct wear pit, while the non-textured sample showed typical wear pit with depth up to 15 μm. Volume wear rate was reduced by 69.6 ± 6.9%. The graphene-like micro-texture array conducted by picosecond fiber laser scanning will not change the material isotropic, and the improved tribological properties are attributed to the combined effects of the increased surface hardness, improved heat dispersion property and entrapment of wear debris.

Self-powered devices and micro-sensors are in high demand for intelligent electronics and flexible wearables for applications in medical healthcare and human–computer interactive robotics. Flexible, stretchable, wearable and breathable high-sensitivity sensors that monitor signals from subtle changes in the environment provide solutions for personalized medical healthcare. In this article, we review the fundamental mechanisms, theoretical research, sensor fabrication methodologies, and applications of flexible piezoelectric materials. We focus on the flexibility and stretchability of inorganic, polymer, and bio-piezoelectric materials, explain their properties for physiological signal monitoring, motion detection, and force sensing. We provide an overview of the latest progress in piezoelectronics and piezoelectric photonics, the structures of devices, and self-powering technologies. We compared 10 types of polymers and composites with human skin in terms of elastic modulus and found that PLLA/PDMS, electro-spun PVDF, and ZnO/PVDF possess higher elastic modulus (50, 500, and 27900 MPa respectively) than human skin (18.8 MPa), thus being more suitable for wearable devices. In terms of electrical outputs of piezoelectric materials, polarized cast film has stronger piezoelectric property with output of 14–45.6 V than electro-spun filaments material (output 0.4–9 V). Future research and development should focus on increasing electrical performance while maintaining the required flexibility and durability.

In this investigation, a picosecond laser was employed to fabricate surface textures on a Stavax steel substrate, which is a key material for mold fabrication in the manufacturing of various polymer products. Three main types of surface textures were fabricated on a Stavax steel substrate: periodic ripples, a two-scale hierarchical two-dimensional array of micro-bumps, and a micro-pits array with nano-ripples. The wettability of the laser-textured Stavax steel surface was converted from its original hydrophilicity into hydrophobicity and even super-hydrophobicity after exposure to air. The results clearly show that this super-hydrophobicity is mainly due to the surface textures. The ultrafast laser-induced catalytic effect may play a secondary role in modifying the surface chemistry so as to lower the surface energy. The laser-induced surface textures on the metal mold substrates were then replicated onto polypropylene substrates via the polymer injection molding process. The surface wettability of the molded polypropylene was found to be changed from the original hydrophilicity to super-hydrophobicity. This developed process holds the potential to improve the performance of fabricated plastic products in terms of wettability control and easy cleaning. Keywords: Picosecond laser, Surface texturing, Stavax steel, Polymer, Hydrophobicity