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Abstract Numerous plants evolve ingeniously microcantilever‐based hairs to ultra‐sensitively detect out‐of‐plane quasi‐static tactile loads, providing a natural blueprint for upgrading the industrial static mode microcantilever sensors, but how do the biological sensory hairs work mechanically? Here, the action potential‐producing trigger hairs of carnivorous Venus flytraps (Dionaea muscipula) are investigated in detail from biomechanical perspective. Under tiny mechanical stimulation, the deformable trigger hair, composed of distal stiff lever and proximal flexible podium, will lead to rapid trap closure and prey capture. The multiple features determining the sensitivity such as conical morphology, multi‐scale functional structures, kidney‐shaped sensory cells, and combined deformation under tiny mechanical stimulation are comprehensively researched. Based on materials mechanics, finite element simulation, and bio‐inspired original artificial sensors, it is verified that the omnidirectional ultra‐sensitivity of trigger hair is attributed to the stiff‐flexible coupling of material, the double stress concentration, the circular distribution of sensory cells, and the positive local buckling. Also, the balance strategy of slender hair between sensitivity and structural stability (i.e., avoiding disastrous collapse) is detailed revealed. The unique basic biomechanical mechanism underlying trigger hairs is essential for significantly enhancing the performance of the traditional industrial static mode microcantilever sensors, and ensure the stability of arbitrary load perception.

Abstract Fibre reinforced polymer composites have become a new generation of structural materials due to their unique advantages such as high specific strength, designability, good dimensional stability and ease of large-area monolithic forming. However, the problem of interfacial bonding between the resin matrix and the fibres limits the direct use of reinforcing fibres and has become a central difficulty in the development of basalt fibre-epoxy composites. This paper proposes a solution for enhancing the strength of the fibre-resin interface using maize starch nanocrystals, which are highly yield and eco-friendly. Firstly, in this paper, corn starch nanocrystals (SNC) were prepared by hydrolysis, and were deposited on the surface of basalt fibers by electrostatic adsorption. After that, in order to maximize the modification effect of nano-starch crystals on the interface, the basalt fiber-epoxy resin composite samples were prepared by mixing in a pressureless molding method. The test results shown that the addition of basalt fibers alone led to a reduction in the strength of the sample. Deposition of 0.1 wt% SNC on the surface of basalt fibers can make the strength consistent with pure epoxy resin. When the adsorption amount of SNC reached 0.5 wt%, the tensile strength of the samples was 23.7% higher than that of pure epoxy resin. This is due to the formation of ether bond homopolymers between the SNC at the fibre-epoxy interface and the epoxy resin, which distorts the originally smooth interface, leading to increased stress concentration and the development of cracks. This enhances the binding of basalt fibers. The conclusions of this paper can provide an effective, simple, low-cost and non-polluting method of interfacial enhancement modification.

Currently, the conventional heat pipe form and working fluid are not well suited for power batteries. Existing simulation studies on battery thermal management with coupled heat pipes often overlook the two-phase flow and heat transfer of working fluid within the heat pipe. Additionally, the temperature difference between electrode region and cell is neglected in thermal behaviour simulation of the battery. Aiming at these problems, this paper proposes the design of an L-shaped heat pipe, which aims to efficiently adapt to heat dissipation of square batteries and the spatial arrangement within the battery module. And the phase change, flow and heat transfer processes of working fluid inside heat pipe are simulated and reproduced using the VOF (volume of fluid) method. Additionally, a CFD (computational fluid dynamics) model of an 8S1P ternary lithium-ion battery module is established based on the NTGK (Newman, Tiedemann, Gu, and Kim) method. Focusing upon thermal behaviour properties of the 8S1P battery module at different discharge rates, we investigate and optimize the thermal management efficiency of L-shaped heat pipes coupled with air cooling. The analysis reveals that the battery module model provides a more accurate representation of the temperature field on the body of batteries and the temperature variation among them. The evaporation-condensation process of the working fluid inside the heat pipe can continue in dynamic equilibrium, and the heat transfer effect through phase transition is well. With battery discharge rates varying from 1C to 3.5C, the addition of forced air cooling and introduction of cold air from air conditioning allows efficient control of temperature and temperature difference of the module, resulting in an ideal cooling effect. This study further improves the accuracy of the design and simulation of BTM (battery thermal management) that coupled with heat pipes, which can provide certain reference for related research.

Abstract Integrating sensors and other functional parts in one device can enable a new generation of integrated intelligent devices that can perform self‐sensing and monitoring autonomously. Applications include buildings that detect and repair damage, robots that monitor conditions and perform real‐time correction and reconstruction, aircraft capable of real‐time perception of the internal and external environment, and medical devices and prosthetics with a realistic sense of touch. Although integrating sensors and other functional parts into self‐sensing intelligent devices has become increasingly common, additive manufacturing has only been marginally explored. This review focuses on additive manufacturing integrated design, printing equipment, and printable materials and stuctures. The importance of the material, structure, and function of integrated manufacturing are highlighted. The study summarizes current challenges to be addressed and provides suggestions for future development directions.

Highlights A bio-inspired flexible strain sensor with hypersensitivity and highly selective frequency response is prepared by styrene–isoprene–styrene combined with monolayer graphene. Benefiting from the structural design inspired by nature and hysteresis of viscoelastic materials, bio-inspired structures, and original materials' properties complement each other. The frequency recognition resolution of bio-inspired flexible strain sensor reaches 0.2 Hz, making it ideal for human–computer interaction and mechanical equipment health inspection.

Carbon fiber composite fan blade (CFCFB) is gradually applied to aerospace because it possesses less density and high strength than metal materials. However, the flexural property of conventional CFCFB is generally limited due to centrifugal and aerodynamic flexural stresses. Herein, a bionic gradient double-twisted structure (BGDTS), which was composed of different modulus carbon fiber prepreg gradient structure (inspired by metopograpsus frontalis cheliped tip) and double-twisted (inspired by coelacanth scale) layup structure was designed. Besides, the flexural properties of laminates with different structures and materials were tested, and the 3D Hashin failure criterion was used for simulation analysis. The experimental and simulation results showed that bionic gradient double-twisted structure laminate (BGDTSL) had the best flexural performance (peak flexural force 1125.12 N). Then, the excellent moulding accuracy of CFCFB was verified by the three-dimensional scanning test (moulding accuracy less than 0.56 mm). Among, the tip, middle, and root peak flexural force of the BGDTS-CFCFB were 7022 N, 3327 N, and 5184 N, which increased by 9.27%, 4.59%, and 14.31% compared with traditional structure CFCFB prepared by T800 (TS-CFCFB@T800). The researches in this work offer a prospective way to effectually devise and manufacture exquisitely structured CFCFBs that are more suitable for aeronautical engineering.

Inspired by the leaf vein structure, this article proposes cooling structures with tapered contracting manifold and leaf vein feature, to optimize the cold plate structure for high heat flux gallium nitride high electron mobility transistors (GaN HEMTs). The correlation between the fluid flow distribution in channels and the temperature uniformity of chips is investigated. The performance of the designed Bionic Structures is compared with that of the traditional Parallel Structure in terms of fluid flow characteristics, heat transfer characteristics and comprehensive performance. Results show that the Bionic Structures with tapered contracting manifold and leaf vein feature improve the fluid flow uniformity by up to 44.1 % and the temperature uniformity of chips by up to 65.0 %, while reducing the pressure drop by up to 24.7 % and the convective heat transfer resistance by up to 32.8 %. The comprehensive performance is also significantly improved. This article demonstrates the great potential of bionic cooling structure for breaking through the thermal management limit of high heat flux power chips.

The dome shaped structures of natural organisms can provide design inspiration for impact resistant structural materials. Most of the existing biomimetic dome shaped impact resistant materials are directly formed using 3D printing technology, and the samples cannot dynamically adjust the impact resistance properties in the various applications. Herein, 4D printing of fused filament fabrication is employed to form flat structures with different structural patterns via programming the printing process parameters, which can be deformed into biomimetic dome structures with dynamic thermal stimulation treatment. The thermal stimulation treatment can drive the dynamic transformation of 2D planar structures into 3D structures, and the higher the thermal stimulation temperature, the greater the degree of eminence and the denser the structure under the same experimental conditions. The thermal stimulation temperature and the mechanical properties of the structural samples show a certain positive correlation. In addition, different design structural patterns have different compressive mechanical properties. The more the number of circular units, the more obvious the energy absorption characteristics. The impact-resistant biomimetic structures can be applied to the surface strengthening and cushioning of various weapons, vehicles, heavy equipment, and launch structure.

Responsive photonic crystals (PCs) with bio-inspired microstructures and tailorable functionalities are of critical importance for their potential applications in diverse fields such as biological detection, sensing, decoration, anti-counterfeiting, etc. However, limited by preparation technologies and design theories, it is still a challenge to accurately and uniformly deposit smart responsive materials on natural PC structures and achieve dual stimulus response. Herein, a simple and rapid in situ polymerization method is presented for preparing dual-responsive PCs with ultra-precise micro-/nanoscale hierarchical structures. Exposure of the reaction site by deacetylation of Morpho butterfly wings allows in situ polymerisation of poly (N-isopropylacrylamide-co-acrylic acid) (P(NIPAAM-co-AAc)) on the surface of the natural photonic structure. The obtained P(NIPAAM-co-AAc) photonic crystals (P(NIPAAM-co-AAc)-PCs) exhibited a dual response to pH and temperature reversibility. In addition, the synergistic effect of the structures and materials on the optical response of the natural PCs is revealed. This work allows the combination of natural hierarchical PC structures with smart hydrogel to achieve an optical response to pH and temperature, thus opening up the channels for responsive PC to multiple stimulus responses.

Accurate simulation of the battery thermoelectric coupling characteristics is the key to the thermal design and thermal management. As the electrically connected component between the battery electrodes, the heat production and heat transfer of the busbars have a significant impact on the battery thermoelectric behavior. A small number of battery thermal management studies have begun to model busbars recently, but the thickness, length, and material of the busbars are diverse. There is a lack of perfect simulation analysis and optimization methods. There is an urgent need to conduct in-depth research on the influence of characteristic parameters of the busbars on the battery thermoelectric behavior. Based on the MSMD-NTGK model, this paper investigates the influence of the thickness, length, and material of the busbars on the battery thermoelectric behavior without considering the economic cost and differences in the battery structure design. In this paper, a simulation analysis method and an ideal improvement solution for the design of the busbars are proposed. This paper compares the changes in the battery thermal behavior before and after the improvement of the busbars under the constant-rate discharge process, FTP75 condition, NEDC condition and WLTC condition respectively. This study can improve the realism of the battery thermal behavior simulation, provide a reliable simulation analysis method and reference basis for the industrial design and optimization of the busbars, and further improve the reliability of the subsequent battery thermal management simulation.

Background. Lung cancer is considered to be the second most aggressive and rapidly fatal cancer after breast cancer. Necroptosis, a novel discovered pattern of cell death, is mediated by Receptor-interacting serine/threonine-protein kinase 1 (RIPK1), Receptor-interacting serine/threonine-protein kinase 3 (RIPK3), and Mixed Lineage Kinase Domain Like Pseudokinase (MLKL). Methods. For the purpose of developing a prognostic model, Least absolute shrinkage and selection operator (LASSO) Cox regression analysis was conducted. Using Pearson’s correlation analysis, we evaluated the correlation between necroptosis-related markers and tumor immune infiltration. A bioinformatics analysis was conducted to construct a necroptosis-related regulatory axis. Results. There was a downregulation of most of necroptosis-related genes in lung adenocarcinoma (LUAD) versus lung tissues but an increase in PGAM5, HMGB1, TRAF2, EZH2 levels. We also summarized the Single Nucleotide Variant (SNV) and copy number variation (CNV) of necroptosis-related genes in LUAD. Consensus clustering identified two clusters in LUAD with distinct immune cell infiltration and ESTIMATEScore. Genes related to necroptosis were associated with necroptosis, Tumor necrosis factor (TNF) signaling pathway, and apoptosis according to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Four prognostic genes (ALDH2, HMGB1, NDRG2, TLR2) were combined to develop a prognostic gene signature for LUAD patients, which was highly accurate in predicting prognosis. Univariate and multivariate analysis identified HMGB1, pT stage, and pN stage as independent factors impacting on LUAD patients’ prognosis. A significant correlation was found between the level of TLR2 and NDRG2 and clinical stage, immunity infiltration, and drug resistance. Additionally, the progression of LUAD might be regulated by lncRNA C5orf64/miR-582-5p/NDRG2/TLR2. Conclusion. The current bioinformatics analysis identified a necroptosis-related prognostic signature for LUAD and their relation to immunity infiltration. This result requires further investigation.

Summary: Weak interfacial strength restricts the mechanical properties of carbon fiber-reinforced composites. Here, inspired by natural hook-groove microstructure system (HGMS) of black kite (Milvus migrans), we detail the steps to construct a biomimetic HGMS based on dopamine-functionalized carbon fibers (CFs) and zinc oxide nanorods (ZnO NRs) using a two-step modification approach. We describe the fabrication of biomimetic carbon fiber composites using vacuum-assisted contact molding (VACM) and subsequent characterization using standard comprehensive mechanical tests techniques.For complete details on the use and execution of this protocol, please refer to Wang et al. (2022). : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.

Antireflective and self-cleaning coatings have attracted increasing attention in the last few years due to their promising and wider applications such as stealth, display devices, sensing, and other fields. However, existing antireflective and self-cleaning functional material are facing problems such as difficult performance optimization, poor mechanical stability, and poor environmental adaptability. Limitations in design strategies have severely restricted coatings’ further development and application. Fabrication of high-performance antireflection and self-cleaning coatings with satisfactory mechanical stability remain a key challenge. Inspired by the self-cleaning performance of nano-/micro-composite structure on natural lotus leaves, SiO2/PDMS/matte polyurethane biomimetic composite coating (BCC) was prepared by nano-polymerization spraying technology. The BCC reduced the average reflectivity of the aluminum alloy substrate surface from 60% to 10%, and the water contact angle (CA) was 156.32 ± 0.58°, illustrating the antireflective and self-cleaning performance of the surface was significantly improved. At the same time, the coating was able to withstand 44 abrasion tests, 230 tape stripping tests, and 210 scraping tests. After the test, the coating still showed satisfactory antireflective and self-cleaning properties, indicating its remarkable mechanical stability. In addition, the coating also displayed excellent acid resistance, which has important value in aerospace, optoelectronics, industrial anti-corrosion, etc.

The rational design of desirable lightweight structural materials usually needs to meet the strict requirements of mechanical properties. Seeking optimal integration strategies for lightweight structures and high mechanical performance is always of great research significance in the rapidly developing composites field, which also draws significant attention from materials scientists and engineers. However, the intrinsic incompatibility of low mass and high strength is still an open challenge for achieving satisfied engineering composites. Fortunately, creatures in nature tend to possess excellent lightweight properties and mechanical performance to improve their survival ability. Thus, by ingenious structure configuration, lightweight structural biomaterials with simple components can achieve high mechanical performance. This review comprehensively summarizes recent advances in three typical structures in natural biomaterials: cellular structures, fibrous structures, and sandwich structures. For each structure, typical organisms are selected for comparison, and their compositions, structures, and properties are discussed in detail, respectively. In addition, bioinspired design approaches of each structure are briefly introduced. At last, the outlook on the design and fabrication of bioinspired composites is also presented to guide the development of advanced composites in future practical engineering applications.

Summary: Weak interfacial activity and poor wettability between fiber and matrix are known to be the two main factors that restrict the mechanical properties of carbon fiber-reinforced composites (CFRCs). Herein, inspired by high strength and toughness characteristics of wing feathers of Black Kite (Milvus migrans), natural hook-groove microstructure system (HGMS) and underlying mechanical interlocking mechanism were carefully investigated. Biomimetic HGMS based on dopamine-functionalized carbon fibers and ZnO nanorods were constructed successfully by a two-step modification method to enhance interfacial adhesion. Further, CFRCs featured with biomimetic HGMS were prepared by a vacuum-assisted contact molding method. Experimental results confirmed that flexural strength and interlaminar shear strength of the bioinspired CFRCs were effectively improved by 40.02 and 101.63%, respectively. The proposed bioinspired design strategy was proved to be flexible and effective and it was anticipated to provide a promising design approach and facile fabrication method for desirable CFRCs with excellent mechanical properties.

This manuscript reviews the development of femoral stem prostheses in the biomedical field. After a brief introduction on the development of these prostheses and the associated problems, we describe the standard design of these systems. We review the different materials, constructions, and surfaces used in the development of femoral stems, in order to solve and avoid various problems associated with their use. Femoral stem prostheses have undergone substantial changes and design optimizations since their introduction. Common materials include stainless steel, cobalt–chromium alloy, titanium alloy, and composites. The structural development of femoral stem prostheses, including their length, shape, porosity, and functional gradient construction, is also reviewed. The performance of these prostheses is affected not only by individual factors, but also by the synergistic combination of multiple effects; therefore, several aspects need to be optimized. The main purpose of this study is to summarize various strategies for the material and construction optimization of femoral stem prostheses, and to provide a reference for the combined optimization of their performance. Substantial research is still needed to develop prostheses emulating the behavior of a real human femoral stem.

Abstract Solid particle erosion is a common phenomenon in engineering fields, such as manufacturing, energy, military and aviation. However, with the rising industrial requirements, the development of anti-solid particle erosion materials remains a great challenge. After billions of years of evolution, several natural materials exhibit unique and exceptional solid particle erosion resistance. These materials achieved the same excellent solid particle erosion resistance performance through diversified strategies. This resistance arises from their micro/nanoscale surface structure and interface material properties, which provide inspiration for novel multiple solutions to solid particle erosion. Here, this review first summarizes the recent significant process in the research of natural anti-solid particle erosion materials and their general design principles. According to these principles, several erosion-resistant structures are available. Combined with advanced micro/nanomanufacturing technologies, several artificial anti-solid particle erosion materials have been obtained. Then, the potential applications of anti-solid particle erosion materials are prospected. Finally, the remaining challenges and promising breakthroughs regarding anti-solid particle erosion materials are briefly discussed.

Abstract In nature, fluid manipulation plays a crucial role in the life of organisms, which has attracted great attentions of research and industry. Here, a functional bionic cilia surface is designed via the simple magnetic field assistance and laser etching technique. Multidirectional droplet transportation occurs on superhydrophobic cilia surface, which has good mechanical, physical, and chemical stability. The as‐prepared surface covered with cilia in the superhydrophobic (WCA of 156 ± 2°) and hydrophobic (WCA of 119 ± 3°) area possess different adhesion state, which can be used for multiple chemical reactions as a microreaction platform. Furthermore, bionic cilia surface can be used as a transport tool in the analysis and detection with average transfer speed of 2.3 cm s−1, which provides new opportunities in the development of small analysis equipment. Importantly, magnetically induced bionic cilia surfaces have broad potential applications in developing smart surfaces, droplet control, lab‐on‐a‐chip, etc.

With the continuous integration and miniaturization of electronic devices, the heat transfer of the electronic devices continues to surge. This means that thermal management equipment with higher heat flux cooling capacity is required to maintain its normal operation. This paper systematically reviews the progress of spray cooling. In the first part, the thermal dissipation mechanism of spray cooling in the non-boiling regime and boiling regime are summarized, and the correlation formula of heat transfer is summarized. In the second part, the influencing factors of various parameters of the nozzle are summarized, the experimental research and numerical simulation research are summarized separately, and some means and methods to strengthen heat transfer are listed. In the third part, we summarize the current application research of spray cooling in some hot new fields, including electronic technology, aerospace, biomedicine, battery safety, etc. The research prospects and challenges in these fields are highlighted. This research provides a timely and necessary study of spray cooling.

Abstract Grasping and manipulation are fundamental ways for many creatures to interact with their environments. Different morphologies and grasping methods of “grippers” are highly evolved to adapt to harsh survival conditions. For example, human hands and bird feet are composed of rigid frames and soft joints. Compared with human hands, some plants like Drosera do not have rigid frames, so they can bend at arbitrary points of the body to capture their prey. Furthermore, many muscular hydrostat animals and plant tendrils can implement more complex twisting motions in 3D space. Recently, inspired by the flexible grasping methods present in nature, increasingly more bio‐inspired soft grippers have been fabricated with compliant and soft materials. Based on this, the present review focuses on the recent research progress of bio‐inspired soft grippers based on impactive gripping. According to their types of movement and a classification model inspired by biological “grippers”, soft grippers are classified into three types, namely, non‐continuum bending‐type grippers, continuum bending‐type grippers, and continuum twisting‐type grippers. An exhaustive and updated analysis of each type of gripper is provided. Moreover, this review offers an overview of the different stiffness‐controllable strategies developed in recent years.

Single-port minimally invasive surgery requires only a single incision, which further reduced intraoperative bleeding, reduced postoperative pain, and improved cosmetic benefits. However, the cooperative operation of multiple surgical instruments and forming an effective workspace under a single micro-incision remain a great challenge. This paper proposes a new type of manual training platform for single-port minimally invasive surgery. The designed surgical instrument imitates the structure of a human arm. The proximal end of the instrument is deployable structures (such as shoulder joint and elbow joint); they form an operating space and provide stable support for the instrument after deployed. In addition, the distal end of the instrument is a flexible instrument (such as a human hand), to realize posture adjustment and perform surgical operations. The surgical instrument implements a series of synergistic movements from placement, deployment, adjustment, and recovery. In addition, the platform includes a retightening force adjusting mechanism for the tendon-driven method and a quick-change mechanism for surgical instruments. A series of experiments on a functional prototype have validated the effectiveness and reliability of the designed platform. It can be convenient for doctors to practice master–slave single-port surgical instruments in a variety of environments.

Abstract Integrated sensor–actuators with exciting functionalities, such as action self‐sensing, position self‐sensing, posture self‐sensing, or active sensing, are promising for applications in biomedical device, human–machine interaction, intelligent self‐protection devices, and humanoid robots. Despite recent progress, it remains challenging to achieve a macroscopical integrated sensor–actuator in a material system with microstructures. To address this critical challenge, a 4D printing bioinspired microstructure strategy is reported to design a high‐performance integrated sensor–actuator capable of simultaneous actuation and sensation. Decoupled thermal stimulation and strain sensation is achieved by combining nanocarbon black/polylactic acid composites with bioinspired gradient microgap structures. As a result, printed integrated sensor–actuators can actively touch objects triggered by thermal stimulation and self‐sense the touching state through the resistance change. It is anticipated that the basic design principle underlying this behavior can be used to develop integrated sensor–actuators of various shapes and functionalities to meet desirable applications.

Inspired by microstructure characteristics of mantis shrimp propodus with high mechanical strength, the bionic continuous carbon fiber (CF) reinforced acrylonitrile butadiene styrene (ABS) resin composite with layered spiral structure was prepared successfully via self-built integration 3D printing. Combined with integration 3D printing demands of continuous carbon fiber reinforced ABS resin, bionic structure model was divided into 10 layers with cylindrical entities which spiralled from 0° to 45°. The 3D printed continuous carbon fibers realized designed specific arrangement direction in ABS matrix, which reappeared the layered spiral structure of mantis shrimp propodus. The existence of bionic layered spiral structure led to the higher tensile strength and impact toughness of bionic composite than that of ABS matrix and ABS/CF composite with unidirectional continuous carbon fiber arrangement via the mechanisms of fracture and pull-out of continuous carbon fibers. The high mechanical properties of integration 3D printed bionic composite proved the effectiveness and feasibility of 3D printing method and bionic layered spiral structure design, which extended the preparation method and application fields of carbon fiber reinforced thermoplastic resin composite in engineering materials.

Inspired by the effect of angle between feather shaft and the feather vane on strength enhancement of feather structure, carbon fiber reinforced epoxy resin composites with eagle feather structure were prepared successfully. Based on liquid-phase oxidation, wettability of carbon fiber was improved, which enhanced bonding strength between reinforcement and matrix and built material base for mechanical strength of bionic composite. With the increase of carbon fiber content (0.1 wt.%, 0.2 wt.%, 0.3 wt.% and 0.4 wt.%), tensile strength and impact toughness of carbon fiber reinforced epoxy resin composites increased first and then decreased. Composites with 0.2 wt.% carbon fiber exhibited optimal mechanical properties, which was used for preparation of bionic composite. Compared with carbon fiber reinforced epoxy resin composite with the traditional vertically arranged structure, the composite material with the bionic structure owned higher tensile strength and impact toughness. The fracture and drawing out of carbon fiber and crack deflection were mechanical mechanism of bionic composite, which provided a new design and preparation method for carbon fiber reinforced epoxy resin composite.

In this study, titanium alloy (Ti-4Al-1.5Mn), magnesium alloy (Mg-Li9-A3-Zn3), or aluminum alloy (Al7075-T6) were used to construct the shell model of helicopter rotor blade to study the solid particle erosion of helicopter rotor blades. The erosion resistance of the three materials at different angles of attack (6°, 3°, or 0°) and particle collision speeds (70, 150, or 220 m/s) was examined using the finite volume method, the discrete phase method, and erosion models. In addition, the leading edge of the helicopter blades was coated with two types of bionic anti-erosion coating layers (V- and VC-type), in an attempt to improve erosion resistance at the angles of attack and particle collision speeds given above. The results showed that Ti-4Al-1.5Mn had the best erosion resistance at high speed, followed by Al7075-T6 and Mg-Li9-A3-Zn3. The angle of attack appeared to affect only the surface area of the blade erosion, while the erosion rate was not affected. Finally, the results of this article showed that the V-type bionic coating had better erosion resistance than the VC-type coating at the same impact speeds. The angle of attack did not have a significant effect on the erosion rate of the bionic coating.

Background/Aims: Lipoprotein glomerulopathy (LPG) is a rare hereditary disease. In this study, we investigated the apoE mutation and the role of double filtration plasmapheresis therapy (DFPP) on a new Chinese patient with LPG. Methods: Renal biopsy was performed on this patient to allow a definitive diagnosis. The mutations in the coding sequence of apoE and the hereditary pedigree of this patient were investigated by DNA sequencing. The patient was treated with DFPP, and clinical parameters before and after DFPP were compared. Results: Two missense mutations were found in this patient: Cys112Arg and Arg25Cys. Arg25Cys was previously designated as APOE Kyoto. Family genotyping showed that Cys112Arg and Arg25Cys mutation were transmitted through his father and his mother, respectively. The patient's parents are healthy so far to date. Possibly there was a dose effect on apoE mutation induced LPG. Furthermore, DFPP treatment was first used on this patient and led to dramatic changes: Proteinuria and apo E values declined, and hemoglobin level increased significantly. Conclusion: APOE Kyoto mutation was found in a new Chinese patient with LPG, accompanied by Cys112Arg. More cases and further functional experiments are needed to investigate the role of these two mutations together in LPG. DFPP is an effective therapeutic modality for improving NS in patients with LPG.

A high-performance flexible pressure sensor is one of the most important components of electronic skin, which can endow artificial devices with human-like capabilities. However, the electronic skin usually relies on the arrays of sensors to simultaneously obtain both pressure magnitude and position, making the data processing time-consuming, tedious, and error-prone. Here, a novel continuous pressure positioning sensor (PPS) with flexible multilayer structures based on a combinatorial bionic strategy is designed and fabricated. This PPS is composed of the pressure sensing layer (PSL) and the pressure positioning layer (PPL). The PSL exhibits high sensitivity (18.87 kPa-1) owing to the bionic crack structures. Based on the connection/disconnection of the upper and lower conductive layers, this PPL exhibits excellent positioning properties with excellent resolution (≈35 µm). More importantly, due to stable signal change and synchronization of signals between the two functional layers (>21 pa), this PPS can recognize the type of signal. Applications of the PPS for pressure monitoring, tire safety monitoring, lunar rover road condition monitoring, and emotional communication in human-computer interaction are further demonstrated to measure magnitude, position, and recognition of pressure signals. So, it will have broad application prospects in fields such as pressure detection and human-computer interaction. [ABSTRACT FROM AUTHOR]