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Adhesion between flexible devices and skin surface facilitates portability of devices and reliable signal acquisition from human body, which is essential for medical therapy devices or monitoring systems. Here, we utilize a simple, cost-effective, and scalable layer-by-layer dip-coating method to fabricate a skin-adhesive multifunctional textile-based device, consisting of three parts: low-cost and easily available airlaid paper (AP) substrate, conductive MXene sensitive layer, and adhesive polydimethylsiloxane (PDMS). The adhesive layer of lightly cross-linked PDMS enables the device to form conformal contact with skin even during human joint bending. The smart textile device exhibits excellent electro-thermal and photo-thermal conversion performance with good cycling stability and tunability. Furthermore, the textile electronics show good electromagnetic interference (EMI) shielding properties due to the good electrical conductivity, as well as sensitive and stable pressure sensing properties for human motion detection. Consequently, this efficient strategy provides a possible way to design multifunctional and wearable electronic textiles for medical applications.

The signal of a self-powered touch sensor based on a TENG is processed to control LEDs.

Pulsed power systems require high-performance capacitors with high energy storage density. In this work, (1 − x)BaTiO3-xBi(Mg1/2Sn1/2)O3 ferroelectric ceramics were synthesized in a solid-state solution. The sample of x = 0.12 (0.88BT-0.12BMS) has excellent energy storage density, wide temperature, and wide frequency stability. The excellent energy density of 4.87 J/cm3 at 315 kV/cm and the energy efficiency of 72% at room temperature for 0.88BT-0.12BMS ceramics were achieved. Furthermore, the 0.88BT-0.12BMS ceramics demonstrated well temperature stabilities in the range of 20–100 °C and very good frequency stability in the range of 1–100 Hz. Through pulsed charging–discharging testing, the current density is calculated as 314.01 A/cm2, and the power density is 21.98 MW/cm3. Moreover, the oxygen vacancies' defects and ferroelectric domain mechanism for enhanced breakdown strength as well as high energy density were discussed. These findings broaden the horizon for lead-free dielectrics and show promising applications for pulse power capacitors.

Pressure sensors show significant potential applications in health monitoring, bio-sensing, electronic skin, and tactile perception. Consequently, tremendous research interest has been devoted to the development of high-performance pressure sensors. In this paper, recent progress on the polymer composite-based flexible pressure sensor is reviewed. The parameters of pressure sensors, including sensitivity, linear response range, detection limit, response speed, and reliability, are first introduced. Secondly, representative types of pressure sensors and relevant working principles are introduced and discussed. After that, the applications in human physiology monitoring, health monitoring, artificial skin, and self-powered smart system are listed and discussed in detail. Finally, the remaining challenges and outlook of polymer composite-based flexible sensors are summarized at the end of this review paper. This work should have some impact on the development of high-performance flexible pressure sensors.

Electronic textiles (E-textiles) have received extensive attention for use in human motion detection, wearable electronics, and artificial intelligence. However, fabrication costs and methodology are still key issues preventing the commercialization of highly sensitive and wearable sensors. Here, simple to prepare low-cost conductive MXene-coated airlaid paper (MXene AP) sensors were fabricated via a dip-coating technique for use as electronic skin. The two-layer MXene AP sensors with a three-dimensional structure display high sensitivity (7.65 kPa−1 at 0–3.3 kPa), a broad sensing range (up to 300 kPa), and a stable response for more than 1000 cycles, presenting good sensitivity, repeatability, and durability, and their mechanism was investigated. Furthermore, origami technology can be used to fold MXene AP into an arbitrary shape with good sensing performance, and multistate conformational changes and simulated human touch can also be detected using the resultant three-dimensional (3D) MXene AP sensors. The wearable MXene AP sensors can be used to monitor human body motion and to collect human physical signals sensitively and accurately in the form of electronic skin. These strategies of folding and layering textile-decorated conductive nanomaterials provide a reference for next-generation textile-based wearable electronics and electronic skin.

Nanomaterials based pressure sensors have obtained world‐wide research interest due to their promising potential applications in health monitoring, artificial intelligence, and electronic skin (e‐skin). Despite the recent progress in sensitivity and detection range of the pressure sensors, the relatively high thickness of the active films has obstructed their applications for e‐skin and degraded the comfortability as wearable devices. We hereby report for the first time a novel pressure sensor based on two‐dimensional metal oxide nanosheets where the gaps between neighboring nanosheets are adjustable. The pressure sensors show a sensitivity of up to 7.2 × 106 kPa–1, which is the highest value ever reported for a pressure sensor. Additionally, the sensor shows good repeatability and excellent stability. The pressure‐sensing ranges can be tuned by adjusting the coverage of the nanosheet film. This work presents an effective strategy to develop ultrathin pressure sensors.

Ambipolar transistors are a type of transistor where both electrons and holes can be transported within the semiconductor layer depending on the applied gate bias. Due to their potential applications in bipolar memories and logic circuits, great effort has been devoted to materials synthesis and construction of novel device configurations in the past a few years. In this chapter, we first give a brief introduction to unipolar transistors, including their working principles and important parameters used to estimate device performance. Then, we introduce the working principles of organic ambipolar transistors, with the ambipolar transistors divided into three types according to the type of semiconductor used. Recent examples and working mechanisms for these three kinds of ambipolar transistors and logic circuits based on them are then introduced and discussed. Additionally, we introduce ambipolar transistors based on two-dimensional semiconductors. We have also included a table to summarize and compare the performance of many reported ambipolar transistors and logic circuits based on them, before providing some concluding remarks.

Health monitoring, e-skin, and soft robotics call for large-area and robust energy-harvesting strategy to powering their embedded sensors and peripheral electronics. Triboelectric nanogenerator (TENG) is an optimum option to energizing self-powered sensors and self-charging systems. Herein, a large-scale facile and compatible bar-assisted printing method is presented to achieve hierarchically microstructured polymer composite triboelectric film with good hydrophobicity to improve the electrical output performance and achieve the robustness of TENG. The electrical outputs of the TENG devices are tuned by imparting the graphite fillers into polydimethylsiloxane (PDMS) with optimal concentration. The achieved microstructured graphite/PDMS composite based TENG supplies high and stable short-circuit current of 42 µA, open-circuit voltage of 410 V, and transferred charges of 160 nC under an applied force of 1.2 N, which are sufficient enough to power wearable sensors or charge the energy storage devices. The TENG devices can charge a 2.2 µf capacitor to 1.5 V within 2 s, lighten 30 commercial green LEDs, and drive an electronic watch as well. Self-powered tactile sensing has also been demonstrated by attaching the TENG devices onto a rubber glove to monitor the process in grasping objects. Furthermore, a large-scale self-powered sensor array is fabricated and utilized to map the spatial pressure distributions. This work not only demonstrates a scalable fabrication of the hierarchically microstructured polymer composite films for high-performance TENGs with high electrical outputs, excellent durability and ambient stability, but also brings insight into the development of future cost-effective and self-powered electronics.

Many low density lipoprotein (LDL) apheresis systems have been applied to patients with hyperlipidemia, but these systems usually work on the basis of complicated equipment and the cost of treatment is expensive. In order to achieve effective treatment of hyperlipidemia at a lower cost, we developed a new LDL apheresis system with dextran sulfate (LAS-DS). In this study, 50 patients with hyperlipidemia were treated 120 times with the new LAS-DS. In each treatment, 600 ± 100 mL of plasma (equal to approximately 25% of the total plasma of patients) was collected by apheresis, and DS solution and calcium chloride solution were added into the collected plasma as LDL absorber and catalyzer, respectively. DS selectively binds LDL cholesterol (LDL-C) under the catalysis of calcium ion and the LDL-C-DS complex is removed by centrifugation. The treated plasma was transfused back into the patients and the excessive calcium in the plasma was removed by the cation exchange column integrated in the transfusion set. After treatment with our new system, the acute mean LDL-C reduction was 97% in the apheresis plasma of hyperlipidemia patients. The corresponding reduction was 55.2% and 69.4% for total cholesterol and total triglyceride. There were insignificant reductions of high density lipoprotein cholesterol (HDL-C) and albumin. The new LDL apheresis system with DS that we developed is very simple to operate without relying on complicated equipment, and it can achieve significant clinical results at a much lower cost compared with existing systems. Based on this study we think the new system can provide a safe, effective and much cheaper means for the treatment of hyperlipidemia patients.

To explore influence of platelet donation on donor's megakaryocytopoiesis, platelet counts and plasma concentrations of thrombopoietin (TPO), interleukin-3 (IL-3), IL-6 and nitric oxide (NO) were determined in 42 frequent platelet donors (undergoing plateletpheresis more than once a month for 24 months and their mean platelet yield of collection was 2.5 x 10(11)), in 62 limited platelet donors (undergoing plateletpheresis less than once a month for 24 months) after a donation-free period of5 weeks and in 40 whole blood donors who never undergoing plateletpheresis after a donation-free period of6 months. The results showed that the TPO levels was significantly lower in frequent platelet donors than in limited platelet donors (P0.01) and whole blood donors (P0.01). There were no significant differences between three groups in platelet counts, IL-3, IL-6 and NO. These findings suggest that the number of megakarocytes significantly increased in frequent platelet donors.

Serological mistypings of HLA-A and HLA-B in 27 cases were analyzed. The results showed that for HLA-A and HLA-B typing, the rates of incorrect antigen assignments were significantly higher than rates of antigen misses (P0.05), but there was no significant difference between HLA-A and HLA-B typings. The frequencies of miss-assigned HLA-A and HLA-B specificities were A1 (66.7%), A3 (50.0%), A11 (13.5%), A9 (11.8%), A19 (7.1%), and B16 (50.0%), B48 (43.9%), B15 (16.7%), B40 (11.1%), B13 (10.0%) and B17 (9.1%). In conclusion, the serologic and DNA-based typing techniques should be reciprocally complementary in HLA-A and HLA-B typing.