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Long‐term surveillance records of cardiac activity are essential for people at potential risk of cardiovascular disease. However, the existing mainstream technologies for cardiac monitoring, such as electrocardiography (ECG) and photoplethysmography (PPG), are inconvenient and prone to skin allergies due to contact measurements. Ballistocardiography (BCG) is a vibration signal related to cardiac activity, which can be monitored in an unconstrained way. Herein, an iontronic textile‐type flexible capacitive pressure sensor (i‐TFCPS) based on ionic liquid doped hollow‐porous fiber is developed to monitor physiological signals. With a high sensitivity of 7.26 kPa−1, a wide pressure range (10 Pa–600 kPa), a fast response time of 30 ms, and decent durability over 3500 cycles, the i‐TFCPS is simultaneously capable of detecting and tracking the static and dynamic changes of sitting posture, and subtle physiological information, such as respiration and BCG signals. Benefits from the iontronic textile as sensitive dielectric, the capacitive pressure sensor is able to monitor the subtle BCG signal under high static pressure in an unconstrained state, showing great potential for unobtrusive cardiac monitoring in home, office and hospital. [ABSTRACT FROM AUTHOR]

Developing a small‐diameter vascular graft with a satisfactory performance in terms of mechanical and biological properties remains a challenging issue because of comprehensive requirements from clinical applications. Polyvinyl alcohol (PVA)/polyacrylamide (PAAm) hydrogels exhibit many desirable characteristics for small‐diameter vascular grafts because of their tunable mechanical properties, especially high compliance. However, poor cells adhesion hinders their application for endothelialization in situ. Therefore, in the present work, polydopamine (PDA) and tetrapeptide Arg‐Glu‐Asp‐Val (REDV) were used to functionalize the hydrogels surface and improve cells adhesion. A series of characterizations were systematically conducted to examine the applicability of coated hydrogels to small‐diameter vascular grafts. Results showed that bare and coated hydrogels have appropriate structural stability, and no significant differences in tensile properties could be found after being coated with PDA or PDA‐REDV. The hydrophilicity of the hydrogels decreased with the coatings of PDA and especially PDA‐REDV to improve protein adsorption, porcine iliac artery endothelial cells (PIECs) adhesion, viability, proliferation, and spreading on the hydrogels. Lower hemolysis percentages and higher blood clotting index values were attained for the hydrogels, suggesting their satisfactory hemocompatibility. Overall, the present work provided insights into the development of a novel hydrogel‐based small‐diameter vascular graft. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:117–127, 2020. [ABSTRACT FROM AUTHOR]

Striving for achievements of anode materials with excellent rate capability and long cycle life is a key to the commercial progress of sodium‐ion batteries. In the present work, we report a spherical MoS2‐C nanocomposite as anode for sodium‐ion batteries (SIBs) with high‐performance. The active materials were prepared via an in situ solvothermal reaction, in which carbon and MoS2 were simultaneously formed in one pot using toluene, acetone and ethanol as solvents. SEM results show that the controlled morphology has relative to the solvents, and the thermal gravimetric (TG) and Raman spectrum results indicated that the carbon was in situ formed. The MoS2‐C nano‐spheres were applied for sodium ion batteries. The results illustrate that MoS2‐C harvested from ethanol demonstrates the best electrochemical performances with long cycling stability (430 mA h g−1 after 100th cycles at 0.2 A g−1) and high rate capability (248 mA h g−1 at 5 A g−1). The superior properties of MoS2‐C nanocoposite benefits from several merits: (1) nanoscale size can short path of Na+ diffusion, enlarge electrode/electrolyte contact area, (2) sphere structure possesses good stress–strain relief during Na+ insertion/extraction reactions and consequently decreases huge volume variation, (3) the carbon in situ formed between MoS2 particles can improve the intrinsically poor electronic conductivity leading to higher rate capability. The novel MoS2‐C architectures provide a new avenue to fabricate carbon coupled with sulfides materials with excellent performances. Spherical MoS2‐C nanocomposite, which was prepared via an in situ solvothermal reaction, has demonstrated the superior electrochemical performances for SIBs with long cycling stability (430 mA h g−1 after 100th cycles at 0.2 A g−1) and high rate capability (248 mA h g−1 at 5 A g−1). [ABSTRACT FROM AUTHOR]

Abstract: Polyethylene glycol terephthalate (PET) fabrics with woven structures have proved to be quite effective for use on large diameter artificial blood vessels. However, their use within small‐diameter artificial blood vessels has been associated with poor long‐term patency, a problem resulting from slow endothelialization on PET and an over hyperplasia of smooth muscle cells. Previous research from our laboratory has revealed that ICAM‐1 can be used as a marker to investigate cell adhesion, an effect which was closely associated with cell behavior on the surface of polycaprolactone (PCL) films. Moreover, we found that the coarseness or pore size of the surface exerts considerable influence on cell adhesion and proliferation on PCL films. In this study, we successfully fabricated six types of PET woven fabrics with varying gradients of tightness and porosities. Levels of ICAM‐1 expression (membrane ICAM‐1 & soluble ICAM‐1) were then determined in these woven fabrics. Our results show that increased levels of mICAM‐1 and decreased levels of sICAM‐1 expression were obtained in HUVECs seeded on these six samples. These findings indicate that cell adhesion and proliferation on fabric surfaces were strongly influenced by their structural parameters, in particular the initial adhesion between the cell and fabric surface. In addition, we also found that extracellular matrix adhesion tends to prefer flat and tight surfaces, which promotes cell‐cell and cell‐matrix interactions, as well as the endothelialization on the surface of PET fabrics. These findings provide some novel insights with regard to the design and application of small‐diameter artificial blood vessels. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 954–964, 2018. [ABSTRACT FROM AUTHOR]

Sleeping disorder is a major health threatening in high-pace modern society. Characterizing sleep behavior with pressure-sensitive, simple fabrication, and decent washability still remains a challenge and highly desired. Here, a pressure-sensitive, large-scale, and washable smart textile is reported based on triboelectric nanogenerator (TENG) array as bedsheet for real-time and self-powered sleep behavior monitoring. Fabricated by conductive fibers and elastomeric materials with a wave structure, the TENG units exhibit desirable features including high sensitivity, fast response time, durability, and water resistance, and are interconnected together, forming a pressure sensor array. Furthermore, highly integrated data acquisition, processing, and wireless transmission system is established and equipped with the sensor array to realize real-time sleep behavior monitoring and sleep quality evaluation. Moreover, the smart textile can further serve as a self-powered warning system in the case of an aged nonhospitalized patients falling down from the bed, which will immediately inform the medical staff. This work not only paves a new way for real-time noninvasive sleep monitoring, but also presents a new perspective for the practical applications of remote clinical medical service. [ABSTRACT FROM AUTHOR]

We developed a focusing imager with a toroidally bent crystal imager. The imager can be used in X-ray imaging of laser fusion experiments. This article discusses the focusing properties of toroidally bent crystal in Bragg geometry. Simulations of spatial resolution for toroidally bent crystals with different conditions including source size and detector position were done using the ray-tracing method. The applicable conditions for optimized two-dimensional (2D) imaging of X-ray source are proposed. Toroidally bent crystal of mica with curvature radius 290 mm in the meridional plane and 190 mm in the sagittal plane is used as imaging element in the experiments. The high-quality visible 2D X-ray image was obtained with the imaging plate due to the high collection efficiency of the bent crystal imaging system. It is demonstrated that the toroidally bent mica crystal could be used in X-ray imaging. By analyzing the image information of the sagittal direction, we find out that the toroidal crystal imager has spatial resolution about 34 μm. © 2012 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 22, 226-232, 2012 [ABSTRACT FROM AUTHOR]

Pulse wave carries comprehensive information regarding the human cardiovascular system (CS), which is essential for directly capturing CS parameters. More importantly, cuffless blood pressure (BP) is one of the most critical markers in CS. Accurately measuring BP via the pulse wave for continuous and noninvasive diagnosis of a disease associated with hypertension remains a challenge and highly desirable. Here, a flexible weaving constructed self‐powered pressure sensor (WCSPS) is reported for measurement of the pulse wave and BP in a noninvasive manner. The WCSPS holds an ultrasensitivity of 45.7 mV Pa−1 with an ultrafast response time of less than 5 ms, and no performance degradation is observed after up to 40 000 motion cycles. Furthermore, a low power consumption sensor system is developed for precisely monitoring pulse wave from the fingertip, wrist, ear, and ankles. A practical measurement is performed with 100 people with ages spanning from 24 to 82 years and different health statuses. The discrepancy between the measured BP results using the WCSPS and that provided by the commercial cuff‐based device is about 0.87–3.65%. This work demonstrates an efficient and cost‐effective way for human health monitoring, which would be a competitive alternative to current complex cardiovascular monitoring systems. A flexible and wearable weaving constructed self‐powered pressure sensor is demonstrated for human health monitoring, which can measure and record the human pulse wave and cuffless blood pressure in a noninvasive manner. Based on the acquired pulse wave data, a user‐friendly and low power consumption sensor system is developed for continuous human health assessment with no restrictions on time and place. [ABSTRACT FROM AUTHOR]