Bioadhesive interface for marine sensors on diverse soft fragile species.

Marine animals equipped with sensors provide vital information for understanding their ecophysiology and collect oceanographic data on climate change and for resource management. Existing methods for attaching sensors to marine animals mostly rely on invasive physical anchors, suction cups, and rigid glues. These methods can suffer from limitations, particularly for adhering to soft fragile marine species such as squid and jellyfish, including slow complex operations, unreliable fixation, tissue trauma, and behavior changes of the animals. However, soft fragile marine species constitute a significant portion of ocean biomass (>38.3 teragrams of carbon) and global commercial fisheries. Here we introduce a soft hydrogel-based bioadhesive interface for marine sensors that can provide rapid (time <22 s), robust (interfacial toughness >160 J m-2), and non-invasive adhesion on various marine animals. Reliable and rapid adhesion enables large-scale, multi-animal sensor deployments to study biomechanics, collective behaviors, interspecific interactions, and concurrent multi-species activity. These findings provide a promising method to expand a burgeoning research field of marine bio-sensing from large marine mammals and fishes to small, soft, and fragile marine animals.

Enhanced osteochondral regeneration with a 3D-Printed biomimetic scaffold featuring a calcified interfacial layer.

The integrative regeneration of both articular cartilage and subchondral bone remains an unmet clinical need due to the difficulties of mimicking spatial complexity in native osteochondral tissues for artificial implants. Layer-by-layer fabrication strategies, such as 3D printing, have emerged as a promising technology replicating the stratified zonal architecture and varying microstructures and mechanical properties. However, the dynamic and circulating physiological environments, such as mass transportation or cell migration, usually distort the pre-confined biological properties in the layered implants, leading to undistinguished spatial variations and subsequently inefficient regenerations. This study introduced a biomimetic calcified interfacial layer into the scaffold as a compact barrier between a cartilage layer and a subchondral bone layer to facilitate osteogenic-chondrogenic repair. The calcified interfacial layer consisting of compact polycaprolactone (PCL), nano-hydroxyapatite, and tasquinimod (TA) can physically and biologically separate the cartilage layer (TA-mixed, chondrocytes-load gelatin methacrylate) from the subchondral bond layer (porous PCL). This introduction preserved the as-designed independent biological environment in each layer for both cartilage and bone regeneration, successfully inhibiting vascular invasion into the cartilage layer and preventing hyaluronic cartilage calcification owing to devascularization of TA. The improved integrative regeneration of cartilage and subchondral bone was validated through gross examination, micro-computed tomography (micro-CT), and histological and immunohistochemical analyses based on an in vivo rat model. Moreover, gene and protein expression studies identified a key role of Caveolin (CAV-1) in promoting angiogenesis through the Wnt/ß-catenin pathway and indicated that TA in the calcified layer blocked angiogenesis by inhibiting CAV-1.

Auditory P300 in individuals with high schizotypy: associations of schizotypal traits with amplitude and latency under different oddball conditions.

Background: The aim of this study was to compare the characteristics of auditory P300 between non-clinical individuals with high and low schizotypal traits, and investigate the relationship between schizotypy and P300 under various oddball conditions. Methods: An extreme-group design was adopted. After screening 1,519 young adults using the Schizotypal Personality Questionnaire (SPQ), sixty-three participants were chosen and divided into two groups (schizotypy group: 31 participants; control group: 32 participants). Basic demographic information was assessed and matched between groups. Depression and anxiety indexes were evaluated and controlled. The P300 component was evoked by an auditory oddball paradigm with different frequencies and durations. Results: (1) The duration P300 amplitude at PZ site was significantly weaker in the schizotypy group than in the control group [F(1,54) = 7.455, p = 0.009, ηp2 = 0.121]. (2) In the schizotypy group, the latency of frequency P300 at PZ site under large-variant oddball condition was significantly correlated with total SPQ scores (rp = 0.451, p = 0.018) and disorganized dimension scores (rp = 0.381, p = 0.050). (3) In the control group, significantly negative correlations was found between the negative dimension score of SPQ and the frequency P300 amplitudes under small variant condition (PZ: rp = -0.393, p = 0.043; CPZ: rp = -0.406, p = 0.035). In addition, a significant negative relationship was found between disorganized dimension scores and the duration P300 latency at CPZ site under large-variant oddball condition (rp = -0.518, p = 0.006). Moreover, a significant negative association was found between the duration P300 amplitude at CPZ site under small-variant oddball condition and negative factor scores (rp = -0.410, p = 0.034). Conclusion: Individuals with high schizotypal traits were likely to have deficient attention and hypoactive working memory for processing auditory information, especially the duration of sounds. P300 effects were correlated with negative and disorganized schizotypy, rather than positive schizotypy. There were diverse patterns of relationship between schizotypal traits and P300 under different oddball conditions, suggesting that characteristics and parameters of target stimuli should be considered cautiously when implementing an auditory oddball paradigm for individuals with schizophrenia spectrum.

Auditory acuity and musical ability in young adults with high schizotypal traits.

BACKGROUND: Despite auditory cognition dysfunction being consistently found in people with schizophrenia, the evidence from non-clinical individuals with schizotypy is rare and inconsistent. No studies thus far have comprehensively assessed the association among auditory perception, musical cognition, and schizotypy in non-clinical samples. AIM: We aimed to explore abnormalities in auditory skills, from basic perception to musical ability, among individuals with schizotypal traits. METHOD: An extreme-group design was adopted. Sixty-six participants from the schizotypy and control groups were screened from 1093 young adults using the Schizotypal Personality Questionnaire (SPQ). Auditory acuity was assessed using four auditory discrimination threshold tests, and musical ability was evaluated through the Montreal Battery of Evaluation of Amusia (MBEA). Basic demographic information and musical backgrounds were assessed and matched, and depression, anxiety, and digit-span index were evaluated and controlled. RESULTS: Elevated sensitivity in auditory perception and improved musical talent were found in young adults with high schizotypal traits. Auditory acuity and musical ability were positively correlated with schizotypy and its factors among participants across groups. A regression analysis in the control group showed that cognitive perceptual scores of SPQ positively predicted auditory temporal sensitivity. The mediation analysis revealed an indirect effect of pure tone duration discrimination between musical rhythmic ability and positive factor of schizotypy. DISCUSSION: Elevated sensitivity in auditory temporal perception and improved musical talent in young adults with high schizotypy may contribute to explaining the variation of auditory process in the development of schizophrenia-spectrum disorders. It can also help elucidate the association between psychopathology and creativity in auditory modality.

Highly Conducting and Stretchable Double-Network Hydrogel for Soft Bioelectronics.

Conducting polymer hydrogels are promising materials in soft bioelectronics because of their tissue-like mechanical properties and the capability of electrical interaction with tissues. However, it is challenging to balance electrical conductivity and mechanical stretchability: pure conducting polymer hydrogels are highly conductive, but they are brittle; while incorporating the conducting network with a soft network to form a double network can improve the stretchability, its electrical conductivity significantly decreases. Here, the problem is addressed by concentrating a poorly crosslinked precursor hydrogel with a high content ratio of the conducting polymer to achieve a densified double-network hydrogel (5.5 wt% conducting polymer), exhibiting both high electrical conductivity (≈10 S cm-1 ) and a large fracture strain (≈150%), in addition to high biocompatibility, tissue-like softness, low swelling ratio, and desired electrochemical properties for bioelectronics. A surface grafting method is further used to form an adhesive layer on the conducting hydrogel, enabling robust and rapid bonding on the tissues. Furthermore, the proposed hydrogel is applied to show high-quality physiological signal recording and reliable, low-voltage electrical stimulation based on an in vivo rat model. This method provides an ideal strategy for rapid and reliable tissue-device integration with high-quality electrical communications.

Electrical bioadhesive interface for bioelectronics.

Reliable functions of bioelectronic devices require conformal, stable and conductive interfaces with biological tissues. Integrating bioelectronic devices with tissues usually relies on physical attachment or surgical suturing; however, these methods face challenges such as non-conformal contact, unstable fixation, tissue damage, and/or scar formation. Here, we report an electrical bioadhesive (e-bioadhesive) interface, based on a thin layer of a graphene nanocomposite, that can provide rapid (adhesion formation within 5 s), robust (interfacial toughness >400 J m-2) and on-demand detachable integration of bioelectronic devices on diverse wet dynamic tissues. The electrical conductivity (>2.6 S m-1) of the e-bioadhesive interface further allows bidirectional bioelectronic communications. We demonstrate biocompatibility, applicability, mechanical and electrical stability, and recording and stimulation functionalities of the e-bioadhesive interface based on ex vivo porcine and in vivo rat models. These findings offer a promising strategy to improve tissue-device integration and enhance the performance of biointegrated electronic devices.

Graded intrafillable architecture-based iontronic pressure sensor with ultra-broad-range high sensitivity.

Sensitivity is a crucial parameter for flexible pressure sensors and electronic skins. While introducing microstructures (e.g., micro-pyramids) can effectively improve the sensitivity, it in turn leads to a limited pressure-response range due to the poor structural compressibility. Here, we report a strategy of engineering intrafillable microstructures that can significantly boost the sensitivity while simultaneously broadening the pressure responding range. Such intrafillable microstructures feature undercuts and grooves that accommodate deformed surface microstructures, effectively enhancing the structural compressibility and the pressure-response range. The intrafillable iontronic sensor exhibits an unprecedentedly high sensitivity (Smin > 220 kPa-1) over a broad pressure regime (0.08 Pa-360 kPa), and an ultrahigh pressure resolution (18 Pa or 0.0056%) over the full pressure range, together with remarkable mechanical stability. The intrafillable structure is a general design expected to be applied to other types of sensors to achieve a broader pressure-response range and a higher sensitivity.

Stretchable, transparent and imperceptible supercapacitors based on Au@MnO2 nanomesh electrodes.

A highly transparent and stretchable electrode based on a Au nanomesh, electrodeposited with a thin layer of MnO2 with a transparency of 84.7% is introduced. The as-prepared transparent, stretchable, and imperceptible supercapacitor (TSPS) exhibits a specific capacitance of 0.53 mF cm-2 and excellent bending stability, together with high stretchability (up to 160% strain).

Intracoronary arterial retrograde thrombolysis with percutaneous coronary intervention: a novel use of thrombolytic to treat acute ST-segment elevation myocardial infarction.

BACKGROUND: Clearance of coronary arterial thrombosis is necessary in patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing urgent percutaneous coronary intervention (PCI). There is currently no highly-recommended method of thrombus removal during interventional procedures. We describe a new method for opening culprit vessels to treat STEMI: intracoronary arterial retrograde thrombolysis (ICART) with PCI. METHODS & RESULTS: Eight patients underwent ICART. The guidewire was advanced to the distal coronary artery through the occlusion lesion. Then, we inserted a microcatheter into the distal end of the occluded coronary artery over the guidewire. Urokinase (5-10 wu) mixed with contrast agents was slowly injected into the occluded section of the coronary artery through the microcatheter. The intracoronary thrombus gradually dissolved in 3-17 min, and the effect of thrombolysis was visible in real time. Stents were then implanted according to the characteristics of the recanalized culprit lesion to achieve full revascularization. One patient experienced premature ventricular contraction during vascular revascularization, and no malignant arrhythmias were seen in any patient. No reflow or slow flow was not observed post PCI. Thrombolysis in myocardial infarction flow grade and myocardial blush grade post-primary PCI was 3 in all eight patients. No patients experienced bleeding or stroke. CONCLUSIONS: ICART was accurate and effective for treating intracoronary thrombi in patients with STEMI in this preliminary study. ICART was an effective, feasible, and simple approach to the management of STEMI, and no intraprocedural complications occurred in any of the patients. ICART may be a breakthrough in the treatment of acute STEMI.

The Deformations of Carbon Nanotubes under Cutting.

The determination of structural evolution at the atomic level is essential to understanding the intrinsic physics and chemistries of nanomaterials. Mechanochemistry represents a promising method to trace structural evolution, but conventional mechanical tension generates random breaking points, which makes it unavailable for effective analysis. It remains difficult to find an appropriate model to study shear deformations. Here, we synthesize high-modulus carbon nanotubes that can be cut precisely, and the structural evolution is efficiently investigated through a combination of geometry phase analysis and first-principles calculations. The lattice fluctuation depends on the anisotropy, chirality, curvature, and slicing rate. The strain distribution further reveals a plastic breaking mechanism for the conjugated carbon atoms under cutting. The resulting sliced carbon nanotubes with controllable sizes and open ends are promising for various applications, for example, as an anode material for lithium-ion batteries.

A One-Dimensional Fluidic Nanogenerator with a High Power Conversion Efficiency.

Electricity generation from flowing water has been developed for over a century and plays a critical role in our lives. Generally, heavy and complex facilities are required for electricity generation, while using these technologies for applications that require a small size and high flexibility is difficult. Here, we developed a fluidic nanogenerator fiber from an aligned carbon nanotube sheet to generate electricity from any flowing water source in the environment as well as in the human body. The power conversion efficiency reached 23.3 %. The fluidic nanogenerator fiber was flexible and stretchable, and the high performance was well-maintained after deformation over 1 000 000 cycles. The fiber also offered unique and promising advantages, such as the ability to be woven into fabrics for large-scale applications.

Preparation of biomimetic hierarchically helical fiber actuators from carbon nanotubes.

Mechanically responsive materials that are able to sense and respond to external stimuli have important applications in soft robotics and the formation of artificial muscles, such as intelligent electronics, prosthetic limbs, comfort-adjusting textiles and miniature actuators for microfluidics. However, previous artificial muscles based on polymer materials are insufficient in generating large actuations, fast responses, diverse deformation modes and high cycle performances. To this end, carbon nanotubes (CNTs) are proposed as promising candidates to be assembled into artificial muscles, as they are lightweight, robust and have high surface-to-volume ratios. This protocol describes a reproducible biomimetic method for preparing a family of hierarchically arranged helical fiber (HHF) actuators that are responsive to solvents and vapors. These HHFs are produced through helical assembly of CNTs into primary fibers and further twisting of the multi-ply primary fibers into a helical structure. A large number of nanoscale gaps between the CNTs and micron-scale gaps between the primary fibers ensure large volume changes and fast responses upon the infiltration of solvents and vapors (e.g., water, ethanol, acetone and dichloromethane) by capillarity. The modes of shape transformations can be modulated precisely by controlling how the CNTs are assembled into primary fibers, multi-ply primary fibers, HHFs and hierarchical springs. This protocol provides a prototype for preparing actuators with different fiber components. The overall time required for the preparation of HHF actuators is 17 h.

A Novel Photoelectric Conversion Yarn by Integrating Photomechanical Actuation and the Electrostatic Effect.

A novel photoelectric conversion device in a yarn type is created by assembling an aligned carbon-nanotube fiber coated with poly(tetrafluoroethylene) and an aligned carbon-nanotube sheet/paraffin wax/polyimide bilayer composite strip together. A high output voltage is achieved with high reversibility and durability.

Fiber-Shaped Perovskite Solar Cells with High Power Conversion Efficiency.

A perovskite solar cell fiber is created with a high power conversion efficiency of 7.1% through a controllable deposition method. A combination of aligned TiO2 nanotubes, a uniform perovskite layer, and transparent aligned carbon nanotube sheet contributes to the high photovoltaic performance. It is flexible and stable, and can be woven into smart clothes for wearable applications.

Tunable Photothermal Actuators Based on a Pre-programmed Aligned Nanostructure.

For various applications, it is challenging but essential to obtain complex tunable mechanical actuations in response to environmental stimuli. Here, a general and effective strategy is developed to produce multiple types of photomechanical actuation (from phototropic/apheliotropic bending to three-dimensional helical buckling) by manipulating the orientation of one-dimensional nanomaterials. These materials are manipulated to mimic plants that generate diverse mechanical motions through the orientation of cellulose fibrils. The photomechanical actuations can be completed in milliseconds and can be performed reversibly without detectable fatigue after 100 000 cycles. This capacity to produce multiple types of photomechanical actuation is further developed to produce complex integrated movements, as demonstrated by a light-manipulated robotic arm and a solar energy harvesting system.

A Shape-Memory Supercapacitor Fiber.

A shape-memory, fiber-shaped supercapacitor is developed by winding aligned carbon nanotube sheets on a shape-memory polyurethane substrate. Despite its flexibility and stretchability, the deformed shapes under bending and stretching can be "frozen" as expected and recovered to the original state when required. Its electrochemical performances are well-maintained during deformation, at the deformed state and after the recovery.

Hierarchically arranged helical fibre actuators driven by solvents and vapours.

Mechanical responsiveness in many plants is produced by helical organizations of cellulose microfibrils. However, simple mimicry of these naturally occurring helical structures does not produce artificial materials with the desired tunable actuations. Here, we show that actuating fibres that respond to solvent and vapour stimuli can be created through the hierarchical and helical assembly of aligned carbon nanotubes. Primary fibres consisting of helical assemblies of multiwalled carbon nanotubes are twisted together to form the helical actuating fibres. The nanoscale gaps between the nanotubes and micrometre-scale gaps among the primary fibres contribute to the rapid response and large actuation stroke of the actuating fibres. The compact coils allow the actuating fibre to rotate reversibly. We show that these fibres, which are lightweight, flexible and strong, are suitable for a variety of applications such as energy-harvesting generators, deformable sensing springs and smart textiles.

An Aligned and Laminated Nanostructured Carbon Hybrid Cathode for High-Performance Lithium-Sulfur Batteries.

An aligned and laminated sulfur-absorbed mesoporous carbon/carbon nanotube (CNT) hybrid cathode has been developed for lithium-sulfur batteries with high performance. The mesoporous carbon acts as sulfur host and suppresses the diffusion of polysulfide, while the CNT network anchors the sulfur-absorbed mesoporous carbon particles, providing pathways for rapid electron transport, alleviating polysulfide migration and enabling a high flexibility. The resulting lithium-sulfur battery delivers a high capacity of 1226 mAh g(-1) and achieves a capacity retention of 75% after 100 cycles at 0.1 C. Moreover, a high capacity of nearly 900 mAh g(-1) is obtained for 20 mg cm(-2), which is the highest sulfur load to the best of our knowledge. More importantly, the aligned and laminated hybrid cathode endows the battery with high flexibility and its electrochemical performances are well maintained under bending and after being folded for 500 times.

A gum-like lithium-ion battery based on a novel arched structure.

Stretchable lithium-ion batteries (LIBs) consisting of an arch structure and a stretchable anode and cathode are developed using a general strategy. The LIB maintains a remarkable and stable electrochemical performance after hundreds of stretching cycles at a strain of 400%. Compared with other stretchable LIBs, which stretch at the device level, but whose components (electrodes) remain rigid, the component-level stretchability is here the design key to the LIB's highly stable performance.