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Enzymatic activity is heavily influenced by pH, but the rationale for the dynamical mechanism of pH-dependent enzymatic activity has not been fully understood. In this work, combined neutron scattering techniques, including quasielastic neutron scattering (QENS) and small angle neutron scattering (SANS), are used to study the structural and dynamic changes of a model enzyme, xylanase, under different pH and temperature environments. The QENS results reveal that xylanase at optimal pH exhibits faster relaxational dynamics and a lower energy barrier between conformational substates. The SANS results demonstrate that pH affects both xylanase’s stability and monodispersity. Our findings indicate that enzymes have optimized stability and function under their optimal pH conditions, with both structure and dynamics being affected. The current study offers valuable insights into enzymatic functionality mechanisms, allowing for broad industrial applications.

E-skins, capable of responding to mechanical stimuli, hold significant potential in the field of robot haptics. However, it is a challenge to obtain e-skins with both high sensitivity and mechanical stability. Here, we present a bioinspired piezoresistive sensor with hierarchical structures based on polyaniline/polystyrene core–shell nanoparticles polymerized on air-laid paper. The combination of laser-etched reusable templates and sensitive materials that can be rapidly synthesized enables large-scale production. Benefiting from the substantially enlarged deformation of the hierarchical structure, the developed piezoresistive electronics exhibit a decent sensitivity of 21.67 kPa–1and a subtle detection limit of 3.4 Pa. Moreover, an isolation layer is introduced to enhance the interface stability of the e-skin, with a fracture limit of 66.34 N/m. Furthermore, the e-skin can be seamlessly integrated onto gloves without any detachment issues. With the assistance of deep learning, it achieves a 98% accuracy rate in object recognition. We anticipate that this strategy will render e-skin with more robust interfaces and heightened sensing capabilities, offering a favorable pathway for large-scale production.

Silicon-based anodes with high theoretical capacity have intriguing potential applications for high energy density lithium-ion batteries (LIBs), while suffer from immense volumetric change and brittle solid-state electrolyte interface that causes collapse of electrodes. Here, a stress-dissipated conductive polymer binder (polyaniline with citric acid, PC) is developed to enhance the mechanical electrochemical performance between Si nanoparticles (SiNPs) and binders. Benefiting from the stable triangle network node of citric acid and a considerable distributed of hydroxyl groups, the PC binder can effectively dissipate the stress from SiNPs, thus providing an excellent cyclic stability of Si anodes. Both experimental results and theoretical calculation demonstrate the enhanced adhesion between binders and SiNPs could bond the particles tightly to form a robust electrode. The as-fabricated Si anode exhibits outstanding structural stability upon long-term cycles that exhibit a highly reversible capability of 1 021 mA·h·g−1over 500 cycles at a current density of 0.5 C (1 C = 4 200 mA·g−1). Evidently, this stress-dissipated binder design will provide a promising route to achieve long-life Si-based LIBs.

The rapid development of the Internet of Things (IoTs) and proliferation of wearable electronics have significantly stimulated the pursuit of distributed power supply systems that are small and light. Accordingly, micro-supercapacitors (MSCs) have recently attracted tremendous research interest due to their high power density, good energy density, long cycling life, and rapid charge/discharge rate delivered in a limited volume and area. As an emerging class of electrochemical energy storage devices, MSCs using polyaniline (PANI) electrodes are envisaged to bridge the gap between carbonaceous MSCs and micro-batteries, leading to a high power density together with improved energy density. However, despite the intensive development of PANI-based MSCs in the past few decades, a comprehensive review focusing on the chemical properties and synthesis of PANI, working mechanisms, design principles, and electrochemical performances of MSCs is lacking. Thus, herein, we summarize the recent advances in PANI-based MSCs using a wide range of electrode materials. Firstly, the fundamentals of MSCs are outlined including their working principle, device design, fabrication technology, and performance metrics. Then, the working principle and synthesis methods of PANI are discussed. Afterward, MSCs based on various PANI materials including pure PANI, PANI hydrogel, and PANI composites are discussed in detail. Lastly, concluding remarks and perspectives on their future development are presented. This review can present new ideas and give rise to new opportunities for the design of high-performance miniaturized PANI-based MSCs that underpin the sustainable prosperity of the approaching IoTs era.

Bismuth (Bi) has emerged as a promising anode material for fast-charging and long-cycling sodium-ion batteries (SIBs). However, its dramatically volumetric variations during cycling will undesirably cause the pulverization of active materials, severely limiting the electrochemical performance of Bi-based electrodes. Constructing hollow nanostructures is recognized as an effective way to resolve the volume expansion issues of alloy-type anodes but remains a great challenge for metallic bismuth. Here, we report a facile iodine-ion-assisted galvanic replacement approach for the synthesis of Bi nanotubes (NTs) for high-rate, long-term and high-capacity sodium storage. The hollow tubular structure effectively alleviates the structural strain during sodiation/desodiation processes, resulting in excellent structural stability; the thin wall and large surface area enable ultrafast sodium ion transport. Benefiting from the structural merits, the Bi NT electrode exhibits extraordinary rate capability (84% capacity retention at 150 A g–1) and outstanding cycling stability (74% capacity retention for 65,000 cycles at 50 A g–1), which represent the best rate performance and longest cycle life among all reported anodes for SIBs. Moreover, when coupled with the Na3(VOPO4)2F cathode in full cells, this electrode also demonstrates excellent cycling performance, showing the great promise of Bi NTs for practical application. A combination of advanced research techniques reveals that the excellent performance originates from the structural robustness of the Bi NTs and the fast electrochemical kinetics during cycling.

The preparation of Pd-based catalysts with rich electrons and a high atom dispersion rate is of great significance for improving the reactivity of cross-coupling reactions, which is a powerful tool for pharmaceutical and fine chemical synthesis. Here, we report a PdNi single-atom alloy (SAA) catalyst in which isolated Pd single atoms are anchored onto the surface of Ni nanoparticles (NPs) applied for Suzuki coupling reactions and Heck coupling reactions. The 0.1% PdNi SAA exhibits extraordinary catalytic activity (reaction rate: 17,032.25 mmol h−1gPd−1) toward the Suzuki cross-coupling reaction between 4-bromoanisole and phenylboronic acid at 80 °C for 1 h. The excellent activity is supposed to attribute to the 100 percent utilization rate of Pd atoms and the highly stable surface zero-valance Pd atoms, which provides abundant sites and electrons for the adsorption and fracture of the C-X (X = Cl, Br, I) bond. Moreover, our work demonstrates the excellent application prospect of SAAs for cross-coupling reactions.

MXene-based microsupercapacitors (MSCs) have promoted the development of on-chip energy storage for miniaturized and portable electronics due to the small size, high power density and integration density. However, restricted energy density and operating voltage invariably create obstacles to the practical application of MSCs. Here, we report a symmetric MXene-based on-chip MSC, achieving an ultrahigh energy density of 75 mWh cm–3with high operating voltage of 1.2 V, which are almost the highest values among all reported symmetric MXene MSCs. The adjustment strategy of acetone on the viscosity and surface tension of MXene ink, along with the natural sedimentation strategy, can effectively prevent the orderly stacking of MXene sheets. Further, we developed an all-in-one Si-electronics with three series MSCs through laser-etching technology, obviously presenting high integration capacity and processing compatibility. Thus, this work will contribute to the development of high integration all-in-one electronics with high energy density MXene-based MSCs.

Deep-blue metal halide perovskite light-emitting diodes (PeLEDs) (450–470 nm) still fall behind their green and red counterparts in terms of efficiency, luminance, and lifetime, badly suffering from excess intrinsic surface defects of metal halide perovskites. Herein, we presented a liquid nitrogen passivation (LNP) strategy to effectually restrain the defects of surface Br vacancy (VBr) for high-quality deep-blue MAPbBr3quantum dots (QDs). This liquid nitrogen (LN) provides a low-temperature environment to reduce the size of MAPbBr3QDs for the green-to-deep-blue emission transformation and impel NH4Br to firmly anchor surface Br ions for VBrpassivation. These irreversible deep-blue MAPbBr3QDs remarkably feature the high photoluminescence quantum yield of 97.64% and the strong stability of 91% remaining photoluminescence intensity against ultraviolet irradiation after 120 min, which are comparable to those of red/green counterparts. Based on these findings, we developed deep-blue PeLEDs with the electroluminescence emission of 455 nm, which is in line with the standard of the National Television Standards Committee (NTSC). Evidently, this LNP strategy may open a way to transform the emission spectra and achieve high-quality deep-blue perovskite QDs, promoting the commercial development of deep-blue PeLEDs.

Precisely tuning emission spectra through the component control of mixed halides has been proved to be an efficient method for procuring deep-blue perovskite LEDs (PeLEDs). However, the inferior color instability and lifetime attenuation, originated from vacancy- and trap-mediated mechanisms under an external field, remain an uninterruptedly formidable challenge for the commercial development of PeLEDs. Here, an ultrafast thermodynamics-induced injection enhancement strategy was employed to promote efficient carrier recombination within perovskite quantum dots (QDs), accompanied by less inefficient charge accumulation and trap generation, enabling deep-blue PeLEDs with improved thermal and spectral stability. The resultant PeLEDs feature an external quantum efficiency (EQE) of 3.66%, a max luminance of 2100 cd/m2at the electroluminescence (EL) of 460 nm, and a halftime of 288 s. This work provides a general platform for promoting the EL performances and a deep insight into unraveling the degradation mechanism of blue PeLEDs.

Byline: Yu-qi. Wang, Wei. Feng, Xiang-yang. Chu, Bo. Yang, Ming. Zhao, Yu'e. Sun Giant cell tumor (GCT) is generally treated with wide surgical excision, but the local bone tissue dysfunction [...]

The naturally microstructure-bioinspired piezoresistive sensor for human–machine interaction and human health monitoring represents an attractive opportunity for wearable bioelectronics. However, due to the trade-off between sensitivity and linear detection range, obtaining piezoresistive sensors with both a wide pressure monitoring range and a high sensitivity is still a great challenge. Herein, we design a hierarchically microstructure-bioinspired flexible piezoresistive sensor consisting of a hierarchical polyaniline/polyvinylidene fluoride nanofiber (HPPNF) film sandwiched between two interlocking electrodes with microdome structure. Ascribed to the substantially enlarged 3D deformation rates, these bioelectronics exhibit an ultrahigh sensitivity of 53 kPa–1, a pressure detection range from 58.4 to 960 Pa, a fast response time of 38 ms, and excellent cycle stability over 50 000 cycles. Furthermore, this conformally skin-adhered sensor successfully demonstrates the monitoring of human physiological signals and movement states, such as wrist pulse, throat activity, spinal posture, and gait recognition. Evidently, this hierarchically microstructure-bioinspired and amplified sensitivity piezoresistive sensor provides a promising strategy for the rapid development of next-generation wearable bioelectronics.

Three‐way catalysts are widely used to control criterion pollutant emissions from the increasing gasoline engines. With the stringent requirements of automotive pollutant emission standards in various countries, Rh has become an irreplaceable component of three‐way catalysts due to its superior NOxelimination, high N2selectivity, and simultaneous elimination of CO and hydrocarbons. In this review, we systematically review the recent development of Rh‐based three‐way catalysts in terms of potential supports and effective active center construction strategies. We further summarize the key role of Rh metal in the three‐way catalytic mechanism and reaction kinetics. Finally, we conclude the current challenges and future opportunities facing Rh‐based catalysts. It is believed that based on the deep understanding of Rh‐based three‐way catalysts, the design of Rh‐based catalysts with good low‐temperature catalytic performance and low cost is expected to be realized in the future. In this paper, we generalized the progress of Rh‐based three‐way catalysts in recent decades from the aspect of the support property and the active sites construction. Subsequently, we elucidate the three‐way reaction mechanism as well as the intrinsic reason leading to deactivation. Finally, we present the exciting challenges and future development of Rh‐based three‐way catalysts.

A dedicated weak current measurement system was designed to measure the weak currents generated by the neutron ionization chamber. This system incorporates a second-order low-pass filter circuit and the Kalman filtering algorithm to effectively filter out noise and minimize interference in the measurement results. Testing conducted under normal temperature conditions has demonstrated the system’s high precision performance. However, it was observed that temperature variations can affect the measurement performance. Data were collected across temperatures ranging from -20to 70∘C, and a temperature correction model was established through linear regression fitting to address this issue. The feasibility of the temperature correction model was confirmed at temperatures of -5and 40∘C, where relative errors remained below 0.1%after applying the temperature correction. The research indicates that the designed measurement system exhibits excellent temperature adaptability and high precision, making it particularly suitable for measuring weak currents.

As the world marches into the era of the Internet of Things (IoT), the practice of human health care is on the cusp of a revolution, driven by an unprecedented level of personalization enabled by a variety of wearable bioelectronics. A sustainable and wearable energy solution is highly desired , but challenges still remain in its development. Here, we report a high-performance wearable electricity generation approach by manipulating the relative permittivity of a triboelectric nanogenerator (TENG). A compatible active carbon (AC)-doped polyvinylidene fluoride (AC@PVDF) composite film was invented with high relative permittivity and a specific surface area for wearable biomechanical energy harvesting. Compared with the pure PVDF, the 0.8% AC@PVDF film-based TENG obtained an enhancement in voltage, current, and power by 2.5, 3.5, and 9.8 times, respectively. This work reports a stable, cost-effective, and scalable approach to improve the performance of the triboelectric nanogenerator for wearable biomechanical energy harvesting, thus rendering a sustainable and pervasive energy solution for on-body electronics.

The mesophilic inorganic pyrophosphatase from Escherichia coli(EcPPase) retains function at 353 K, the physiological temperature of hyperthermophilic Thermococcus thioreducens, whereas the homolog protein (TtPPase) from this hyperthermophilic organism cannot function at room temperature. To explain this asymmetric behavior, we examined structural and dynamical properties of the two proteins using molecular dynamics simulations. The global flexibility of TtPPase is significantly higher than its mesophilic homolog at all tested temperature/pressure conditions. However, at 353 K, EcPPase reduces its solvent-exposed surface area and increases subunit compaction while maintaining flexibility in its catalytic pocket. In contrast, TtPPase lacks this adaptability and has increased rigidity and reduced protein/water interactions in its catalytic pocket at room temperature, providing a plausible explanation for its inactivity near room temperature.

Rich chemistry and surface functionalization provide MXenes enhanced electrochemical activity yet severely exacerbate their self-discharge behavior in supercapacitors. However, this self-discharge behavior and its related mechanism are still remaining issues. Herein, we propose a chemically interface-tailored regulation strategy to successfully unravel and efficiently alleviate the self-discharge behavior of Ti3C2TxMXene-based supercapacitors. As a result, Ti3C2TxMXenes with fewer F elements (∼0.65 atom %) show a positive self-discharge rate decline of ∼20% in comparison with MXenes with higher F elements (∼8.09 atom %). Such decline of the F elements can highly increase tight-bonding ions corresponding to an individual self-discharge process, naturally resulting in a dramatic 50% increase of the transition potential (VT). Therefore, the mixed self-discharge rate from both tight-bonding (contain fewer F elements) and loose-bonding ions (contain more F elements) is accordingly lowered. Through chemically interface-tailored engineering, the significantly changed average oxidation state and local coordination information on MXene affected the interaction of ion counterparts, which was evidently revealed by X-ray absorption fine structures. Theoretically, this greatly improved self-discharge performance was proven to be from higher adsorption energy between the interface of the electrode and the electrolyte by density functional theory. Therefore, this chemically interface-tailored regulation strategy can guide the design of high-performance MXene-based supercapacitors with low self-discharge behavior and will promote its wider commercial applications.

To discover novel nitrogen mustards, the reported mustard pharmacophore was combined with natural pentacyclic triterpenes, which are characterized with pharmacological and structural diversity. Thus, six conjugates were synthesized with 1,2,3‐triazole linking N,N‐bis (2‐chloroethyl)‐1,4‐phenylenediamine and oleanolic acid, ursolic acid, or glycyrrhetinic acid, and their biological activity was evaluated against tumor cell lines HeLa, BGC‐823, BEL‐7404, and NCI‐H460 using the MTT assay. As a result, these conjugates showed some selective cytotoxicity to NCI‐H460, though all their activity potency was moderate or weak in the four cell lines. We report the synthesis and evaluation of cytotoxicity of novel pentacyclic triterpenes conjugated with N,N‐bis (2‐chloroethyl)‐1,4‐phenylenediamine via application of “click chemistry.”

The yield of the quaternary nitrogen-containing Ti3AlCN ceramics was evidently proved to be up to 70% by the controllable AlN-oversaturation precursor strategy. Such relatively high-yield quaternary Ti3AlCN is mainly ascribed to the elimination of Al segregation.

Solid-state composite polymer electrolytes (CPEs) usually suffer from intrinsic low ionic conductivity and a solid–solid interface, badly inhibiting their widespread commercial application in all-solid-state Li-metal battery (ASSLMB) energy storage. Herein, a synergetic strategy using strong Lewis acid–base and weak hydrogen bonds was employed for self-assembly in situ construction of three-dimensional (3D) network-structured poly(ethylene oxide) (PEO) and SiO2CPEs (PEO@SiO2). Ascribed to this synergistically rigid–flexible coupling dynamic strategy, a harmonious incorporation of monodispersed SiO2nanoparticles into PEO could remarkably reduce crystallinity of PEO, significantly enhancing the ionic conductivity (∼1.1 × 10–4S cm–1at 30 °C) and dramatically facilitating solid electrolyte interface stabilization (electrochemical stability window > 4.8 V at 90 °C). Moreover, the PEO@SiO2-based ASSLMBs possess excellent rate capability over a wide temperature range (∼105 mA h g–1under 2 C at 90 °C), high temperature cycling capacity (retaining 90 mA h g–1after 100 cycles at 90 °C), and high specific capacity (146 mA h g–1under 0.3 C at 90 °C). Unambiguously, these high ionic conductivity CPEs along with excellent flexibility and safety can be one of the most promising candidates for high-performance ASSLMBs, evidently revealing that this synergistically rigid–flexible coupling dynamic strategy will open up a way to exploit the novel high ionic conductivity solid-state electrolytes.

Heteroatom-functionalized porous carbon has long been regarded as a promising electrode material to construct high-performance capacitive energy storage devices. However, the development of this field is seriously limited due to the lack of an in-depth understanding of the ion-sorption dynamics. Herein, the component and structure controllable N, O, and Cl codoped bimodal (micro-to-meso) porous carbons were prepared and further used as the investigated object for exploring the intrinsic ion-sorption dynamics, which is the root of the enhanced electrochemical response in capacitive energy storage devices. Voltammetry response analysis is employed to quantify the charge storage contributions from both electrostatic adsorption effect (electrical double-layer capacitance) and highly reversible redox process (pseudocapacitance). The existence of electronic capacitance enables a positive correlation between surface capacitance and the ratio of micropores. Besides, an electron-dependent correlation between the electroactive functional groups and redox reaction induced capacitance is also explored. This work will advance the capacitive energy storage field by presenting a clear understanding of the ion-sorption dynamics in the functionalized porous carbons.

Bare Pd metal nanoparticles invariably suffer from poor selectivity in furfural hydrogenation by forming flat configurations, with the aromatic ring of the substrate molecules parallel to the metal surface. Herein, we put forward a promising solution by using CeO2as promoters to modify Pd nanoparticles for modulating the adsorption behaviors of furfural molecules. To achieve the highly-desired ultra-small Pd@CeO2core@shell nanostructure, a “constrained auto-redox” synthesis is developed, in which silicalite-1 supports play the key role of providing their surface as the landing place of PdOxprecursors for inhibiting the overgrowth and the deformation. To the best of our knowledge, this is one of the smallest core@shell materials obtained from aqueous synthesis. When evaluated as catalysts, Pd@CeO2/S-1 gives 98.9% conversion of furfural with 94.3% selectivity for furfural alcohol in 15 h, which is much better than that of Pd/S-1 (88.6% conversion with 44.3% selectively). The DFT simulation reveals a strong interaction between the defects of CeO2and the oxygen atom of the –CHO group in furfural molecules, which benefits the selective hydrogenation occurred in the –CHO group rather than the furan ring.

The cryopreservation of cancer tissues to generate frozen libraries is a common practice used worldwide for storing patient samples for later applications. However, frozen samples stored by existing methods cannot be used for initiating living cell cultures, such as patient-derived tumor organoids (PDOs), which offer great potential for personalized treatment. To overcome this challenge, we developed a novel procedure for culturing PDOs using frozen live tumor tissues. We show that tumor specimens stored using this technique maintain their viability and can be successfully used to generate organoids even after long-term freezing, with an impressive success rate of 95.2%. Importantly, we found that the structural features, tumor marker expression, and drug responses of organoids derived from frozen tissues are similar to those derived from fresh tissues. Moreover, organoids derived from frozen tissues can be routinely passaged and frozen, making them ideal for high-throughput drug screening at any time. Notably, cryopreserved tumor tissues can also be utilized in air-liquid interface (ALI) culture. This method allows for preserving the original tumor microenvironment, making it an invaluable resource for conducting tests on antitumor drug responses, including immune checkpoint inhibitors (ICIs). This innovation has the potential to enable the identification of potentially effective drugs for patients and facilitate the development of novel therapeutic drugs. Thus, we have established protocols for the long-term cryopreservation of cancer tissues to maintain their viability and microenvironment, which are useful for personalized therapy.

1.Hepatocyte-specific Notch1deficiency impairs hepatic thrombopoietin production and reduces circulating platelet number.2.Dll4 on desialylated platelets activates hepatocyte Notch1 signaling and upregulates HES5 expression, leading to JAK2/STAT3 phosphorylation.

Autism spectrum disorder (ASD) is a complex neurological and developmental disorder that affects how a person acts, communicates, learns, and interacts with others. It affects the structure and function of the brain and nervous system. How ASD is caused remains uncertain and there is no effective treatment for this disorder. Searching for new technologies for treatment of this disorder becomes a priority. Genetic alterations have been implicated in the generation of this disorder. One of the most promising genes for potential treatment of ASD is sodium voltage-gated channel alpha subunit 2 gene (SCN2A). SCN2A, encoding the neuronal voltage-gated Na+ channel NaV1.2, is one of the most commonly affected loci linked to ASD. Here, we discuss the implications of loss of function (LOF) mutations in SCN2Aand the potential efficacy of gene therapy by highlighting the usage of CRISPR restoration of various Scn2a-insufficiencies. Various therapeutics exist that can be extrapolated to address the needs of Scn2aLOF induced ASD. The current treatment that exists for ASD can be seen as outdated in comparison to the advent of new technologies that build upon CRISPR. Due to complications in treatment of ASD, genetic therapies may induce alterations such as insertion–deletion mutations, which may lead to further complications along with a negative public outlook on CRISPR technologies. Gene therapy can be applied to ASD but much work is yet to be done in order to address both biochemical and ethical considerations.

Ligamentum arteriosum calcification is the calcification or ossification of arterial ligaments. However, on computed tomography images, ligamentum arteriosum calcification is often mistaken for esophageal perforation when a patient has a medical history of foreign body ingestion. Ligamentum arteriosum calcification is uncommon in clinical practice. In this case report, we confirm the presence of this condition intraoperatively, which has seldom been reported previously. Increased awareness of the clinical characteristics of this uncommon disease can help thoracic surgeons with proper patient management.

Real-time monitoring of interaction between ball and racket can provide the extremely important information for high quality guidance of individual table tennis training. However, the existing visual monitoring system is hard to reflect the specific interaction force and accurate hit position. Here, we design a self-powered rich lamellar crystal baklava-structured PZT/PVDF piezoelectric sensor for real-time monitoring of table tennis training and the scalable sports. This unique baklava-structured piezocomposite could be massively manufactured by a facile two step method of nonsolvent induced phase separation and hot-press process. As a result, the as-developed sensor exhibits preeminent sensitivity (6.38 mV/N) and ultrafast response time (21 ms). On this basis, we made a smart table tennis racket embedded with 6 × 6 units, which could real-timely fetch the hit location and contact force, then it could provide evaluation and individual guidance for the athletes training. Admittedly, this work not only opens a new way for real-time monitoring of impact location and force in table tennis training beyond current visual detection system, but also paves a new prospect for artificial intelligence electronics toward smart sports.

An axle molecule 12+containing one viologen nucleus and two identical p‐toluic acid sides was synthesized. The sequential binding of the Q[7] wheels to the 12+axle leads to the formation of a molecular shuttle and then a homowheel, [3]pseudorotaxane. The [3]pseudorotaxane can reversibly transform to [2]pseudorotaxane by acid‐base control. On the other hand, the initially formed molecular shuttle can also transform to [2]pseudorotaxane directly and reversibly under pH control. As a whole, a molecular shuttle and [3]/[2]pseudorotaxanes constructed a pH‐controlled multiple interconvertible system. Spare wheels: A pH‐controlled multiple interconvertible system is described. It comprises a molecular shuttle, [3]pseudorotaxane and [2]pseudorotaxane based on cucurbit[7]uril was established.

Interactive human-machine interface (iHMI) is a bridge connecting human beings and robots, which has an important requirement for perceiving the change of pressure and bending angle. Here, we designed a flexible self-powered piezoelectric sensor (PES) based on the cowpea-structured PVDF/ZnO nanofibers (CPZNs) for remote control of gestures in human-machine interactive system. Due to the synergistic piezoelectric effect of hybrid PVDF/ZnO and the flexibility of polymer, this PES exhibited excellent bending sensitivity of 4.4 mV deg−1ranging widely from 44° to 122°, fast response time of 76 ms, and good mechanical stability. Besides, the PES could operate under both bending and pressing mode, show ultrahigh pressing sensitivity of 0.33 V kPa−1, with response time of 16 ms. When integrated in iHMI, the PES could be conformably covered on different curve surfaces, demonstrated accurate bending angle recording and fast recognition for realizing intelligent human-machine interaction. On this basis, the application of remote control of robotic hand was successfully realized in form of acting the same gesture as human hand synchronously. This CPZNs-based self-powered PES is distinct and unique in its structure and fundamental mechanism, and exhibits a prospective potential application in iHMI.

Sensing devices with wearability would open the door to many advanced applications including soft robotics, artificial intelligence, and healthcare monitoring. Here, inspired by the configuration of the human epidermis, we present a flexible three-dimensional (3D) cellular sensor array (CSA) via a one-step thermally induced phase separation method. The CSA was framed by the 3D cellular electret with caged piezoelectric nanoparticles, which was ultrathin (80 μm), lightweight, and highly robust. For biomedical sensing, the 3D-CSA holds a decent pressure sensitivity up to 0.19 V kPa–1with a response time of less than 16 ms. Owing to its rigid structural symmetry, the 3D-CSA could be identically operated from its both sides. It was demonstrated to successfully measure the human heartbeat, detect the eyeball motion for sleeping monitoring, and tactile imaging. Mimicking the functionalities of the human skin with a self-powered operation feature, the 3D-CSA was expected to represent a substantial advancement in wearable electronics for healthcare.

The strong piezoelectric lead zirconate titanate (PZT) ceramic with inherent brittleness and highly tough Poly (vinylidene fluoride) (PVDF) polymer with intrinsic weak piezoelectricity cannot simultaneously fulfill the requirements of high sensitivity and excellent stability as a piezoelectric acceleration sensor in extreme service environments, such as intense impact. Here, we developed a polarization-free high-crystallization β-PVDF (hβ-PVDF) based piezoelectric nanogenerator (PENG) as acceleration sensor with high sensitivity (2.405 nA s2m−1) and excellent stability (97% remaining after 10000 cycles). Fundamentally, the excellent performance benefits from the PVDF by high-pressure melt crystallization with a high β-phase crystallinity of 86.48%, indicative of the enhanced piezoelectricity (high short-circuit current density of 145 nA cm−2). With integration of PENGs in three axes, the self-powered 3D acceleration sensor is developed for vector acceleration measurement in any directions. Moreover, a dynamic 3D frequency and acceleration sensor system is targetedly applied to cooperate the acceleration sensor for real-time collision monitoring and alert signal transmission, which presents a significant step toward vehicle safety monitoring. Therefore, we believe this easy process of hβ-PVDF and device has potential for commercial production in the field of transportation, self-powered devices, and energy harvesting.

Scheelite-structure tungstates with unique structural features and excellent luminescence possess promising applications, such as light-emitting diodes (LEDs), scintillators, and displays. The controllable growth of high quality and uniform composition thin films mounted on cheap substrates is a key factor to realize the above commercial applications, however, which is also a big challenge due to the difficult stress release stemming from intrinsic lattice mismatches. Here, we employed the simple and composition-controlled polymer-assisted deposition (PAD) method to successfully obtain a series of high quality and well-proportioned BaWO4:Eu3+(BWOE) thin films with red emission. Screening out the unbound freedom metal ions by poly(ether imide) (PEI) and ethylene diamine tetraacetic acid (EDTA), the firmly bound metal ions (Ba2+, W6+and Eu3+) in polymer solution were applied to accurately control the chemical composition and effectively governed the release of stress during the growth process of BWOE thin films. Furthermore, XRD, SEM and EDS mapping detections evidently authenticated the quasi-single crystallinity, uniform morphology and well-distributed composition of as-grown thin films. Additionally, excited by 250 nm light, these thin films could efficiently produce the red emission, peaked at around 612 nm originated from the 5D0→ 7F2transition of Eu3+. Moreover, the optimal doping concentration of thin films was confirmed to be 9% and corresponding Commission International de l’Eclairage (CIE) chromaticity coordinate was (0.618, 0.365), which evidently implied the excellent color rending index. Therefore, this work highlights the rather superior PAD method to prepare uniform and high-quality BWOE thin films, which can be expanded toward the other photoelectric devices including white lighted-emitting diodes, scintillators, displays, and photoelectric detectors.

The embrittlement of nickel-based structural alloys by fission-produced tellurium (Te) is a major challenge for molten salt reactors (MSR). In this study, the effects of thermal exposure time on tellurium diffusion in a candidate MSR structural alloy (Ni–16Mo–7Cr–4Fe) and the consequent mechanical property degradation of the alloy were investigated through surrogate diffusion experiments at 700 °C. The results show that some tellurium reacted with the alloy to form tellurides on the surface, while some tellurium diffused into the alloy along grain boundaries. Ni3Te2and CrTe were the most stable reaction products at the tested temperature, and the formation of CrTe on the surface induced the Cr depletion at grain boundaries of the alloy. The diffusion depth of Te increased gradually with thermal exposure time, and the diffusion rate kept stable within the test duration of up to 3000 h. The Te diffusion in the alloy caused the embrittlement of grain boundaries, inducing crack formation and strength degradation in tensile test at room temperature.

AbstractBackground:Video-assisted thoracoscopic surgery (VATS) thymectomy has become a feasible treatment for myasthenia gravis (MG) in recent years. The objective of the present meta-analysis was to evaluate the perioperative characteristics, safety, and completely stable remission rate in patients with MG who received VATS or open thymectomy (OT).Methods:We searched PubMed, Embase, ScienceDirect, Web of Science, and CNKI for related articles using combinations of the search terms video-assisted thoracoscopic thymectomy, transsternal thymectomy, and MG. The inter-study heterogeneity was assessed by χ2-based Qstatistics, and the extent of inconsistency was generated by I2statistics.Results:A total of 12 studies with 1173 patients were included, and there was no difference in the operation time (p = 0.08) and ICU time (p = 0.14) between the two groups, but VATS thymectomy was associated with less intra-operation blood loss and hospital time (p < 0.00001). VATS was also associated with lower rates of total complication (OR =0.59; 95% CI, 0.37–0.94; p = 0.03) and myasthenic crisis (OR = 0.51; 95% CI, 0.28–0.92; p = 0.03), but the rates of pneumonia (OR = 0.59; 95% CI, 0.29–1.32; p = 0.21) and complete remission rate (CSR) (OR = 0.64; 95% CI, 0.38–1.09; p = 0.10) had no obvious differences between the VATS and OT groups.Conclusion:Patients with MG undergoing VATS thymectomy achieved better surgical outcomes and fewer complications than those who received OT.

To fundamentally understand the underlying interfacial physics of hole transporting layer is a key to rotationally engineer high-performance light-emitting diodes (LEDs). Here, we unravel the hole interlayer-dependent interfacial energetics of LEDs via combining imaged contact potential/polarization difference, and multi-time scale capacitance/voltage response. A universally existing but undesired stagnation of current density with voltages, under the direct contact of light-emitting Poly-TPD with electrodes, was proved to be rooted from the alternant dominance of capacitance/resistance behaviors with alternating strong/weak polarizations of Poly-TPD. The introduction of hole interlayer (PEDOT:PSS) with more disordered polarization direction and greater intensity can build plentiful carrier hopping channels and ensure the rapidly dynamic charge transfer from electrodes to Poly-TPD, conducing to the increased capacitive reactance contribution at low voltages and inductive effects at high voltages. Also, we clarify its frequency-response difference for emerging high-speed modulation application. This discovery might enable us to explore the next-generation high-efficiency display and optical data-communication.

This paper aims to discuss the diagnostic value of quantitative DTI on AIDS patients with brain tuberculosis or toxoplasmosis.

Experimental study on the catalytic activity of Cu&Fe molecular sieve catalyst with different NSR on NOx conversion efficiency, and explore the influence of temperature and airspeed to ammonia storage characteristics, analysis the relationship between the ammonia storage amount and the NOx conversion efficiency. The experimental result shows that: The catalytic activity can be more than 90% when the catalyst at 300℃-400℃, and an appropriate increase in NSR can improve the NOx conversion efficiency. The influence of temperature on the characteristics of the reservoir ammonia greater than the airspeed, At 200℃-250℃, the NOx conversion efficiency and the amount of ammonia storage linear relationship. Use dynamic variable gain feedback control SCR system urea injection system, which effectively control the ammonia leak to make it satisfy China-V emission regulations.

A new ruthenium complex containing bidentate xanthate ligands was synthesized in a good yield. This complex was characterized by elemental analysis, proton nuclear magnetic resonance(1H NMR), Fourier transform infrared(FTIR) and UV-Vis spectroscopies. The cyclic voltammetry of the complex revealed one quasi-redox wave centered at Ru(III)/ Ru(II) couple, indicating its catalytic potential. So the preparation of a glass carbon electrode modified with ruthenium xanthate complex and its electrocatalytic activity toward the oxidation of tryptophan(Trp) were also studied. The experimental results show that the modified electrode had excellent electrocatalytic activity for the oxidation of tryptophan. Moreover, under the optimized conditions, the oxidation peak current was proportional to tryptophan concentration in a range of 2.5×10−7to 5.0×10−5mol/L with a correlation coefficient of 0.9928 and a detection limit of 8.3×10−8mol/L(S/N=3). Using the proposed method, tryptophan was successfully determined in pharmaceutical samples with standard addition method.

A device for measuring high-TC superconducting transition temperature in a small cryocooler is described which allows a samples temperature to fall steadily from room temperature to 45K. This cryocooler not only meets the high-TC superconductors measurement requirements, but also yields accurate measurement results under ambient conditions. In this device, two measurement methods for measuring high-TC superconducting transition temperature are applied: the electric transport and the AC susceptibility. The former adopts a four-wire method to eliminate the contact resistance between the leads and the sample. During the measurement process the current reversal method for datum processing is applied to eliminate the thermoelectric voltages; this ensures the repeatability error less than 0.4K in the measurement of the superconducting transition temperature. The AC susceptibility method adopts a lock-in amplifier to provide an AC voltage signal for the primary coil, and then lock-in amplifier is used to measure the electrical signals of the secondary coil according to the AC magnetic susceptibility values. The advantage of this device is that by merely changing the position of the sample in the vacuum chamber, the R-T curve and the χ-T curve of a superconducting sample in the same temperature range can be automatically recorded, which provides reliable data for high-TC superconductor transition curve measurement.

In this paper, a graphene modified glassy carbon electrode (GR-GCE), a carbon nanotube modified glassy carbon electrode (CNT-GCE), a carbon nanotube–graphene modified glassy carbon electrode (CNT–GR-GCE), and a gold nanoparticle–carbon nanotube–graphene modified glassy carbon electrode (GNP–CNT–GR-GCE) were prepared and characterized by FT-IR, atomic force microscopy (AFM), and electrochemical methods respectively. Electrogenerated chemiluminescence (ECL) of luminol was comparatively studied at these modified electrodes in neutral solution. The results revealed that carbon nanotube could intercalate into the graphene film and improve the conductivity of the CNT–GR composite significantly. The CNT–GR composite is an ideal matrix for the deposition of gold nanoparticles. At the GNP–CNT–GR-GCE, the effect of GR on luminol ECL is more predominant than that of CNT while the electrocatalytic effect of GNP on luminol ECL is well preserved. These nanomaterials exhibit a good synergic effect towards luminol ECL, which is more efficient than that of the sole material. The volume ratio of GR and CNT, the amount of modified suspension, the presence of N2and O2, and the supporting electrolytes could affect luminol ECL. Finally, the mechanisms of luminol ECL at the modified electrodes were proposed.

Establishment of symptoms diagnostic criteria and treatment effect evaluation index system of Traditional Chinese Medicine is to improve the basic means of scientific medicine. A rational model of TCM symptoms diagnosis is to establish formation of effective evaluation index system. The study is base on the clinical data of bacterial pneumonia in the elderly. First pre-treatment basic data is proceeding. Then deleting unnecessary targets and discovering the core indicator set using Pawlak data reduction algorithms based on rough set theory, the core indicator set is determined as the diagnostic criteria of bacterial pneumonia for the elderly. The modeling method of Chinese medicine diagnosis symptoms on bacterial pneumonia for the elderly has worthy of promotion in Chinese medicine diagnosis symptoms.

According to the characteristics of college training and requirements of the society for talents, the decision support system of college training is designed in this paper. Targeted at graduates’ employment, a data warehouse for college students is set up and online analytical processing and data mining are conducted so as to find out the key factors that affect graduates to find a job. The experimental results are in line with the reality, which shows that decision support system of college training is a powerful auxiliary decision-making tool.

Based on piezoceramic stack actuators, a stage (dimension of 50mm×50mm×11mm) with a symmetric displacement magnifying mechanism is studied in this paper. FEM simulations are carried out to reveal the performance of the micropositioning stage and the amplification radio of the flexure hinge is 4.76. The working mode of the flexure hinge of the stage is also simulated by finite element method, and its natural frequency is 3291Hz. A series of tests about piezoceramic stack actuators have been done, including static, dynamic and temperature tests. The experimental results are identical to the theoretical analysis and give help to the application of piezoceramic stack actuators. It can also help the precise micropositioning stage driven by PZT to achieve higher positioning accuracy and resolution.

Protons are important signals for neuronal function. In the central nervous system (CNS), proton concentrations change locally when synaptic vesicles release their acidic contents into the synaptic cleft, and globally in ischemia, seizures, traumatic brain injury, and other neurological disorders due to lactic acid accumulation. The finding that protons gate a distinct family of ion channels, the acid-sensing ion channels (ASICs), has shed new light on the mechanism of acid signaling and acidosis-associated neuronal injury. Accumulating evidence has suggested that ASICs play important roles in physiological processes such as synaptic plasticity, learning/memory, fear conditioning, and retinal integrity, and in pathological conditions such as brain ischemia, multiple sclerosis, epileptic seizures, and malignant glioma. Thus, targeting these channels may lead to novel therapeutic interventions for neurological disorders. The goal of this review is to provide an update on recent advances in our understanding of the functions of ASICs in the CNS.

Osmium (Os) may be used as new barrier material in copper interconnects of ultra-large scale integration. In this work, chemical mechanical polish experiments were done on Os disk using home-made slurry, the effect of pH value, down force, chelating agents, inhibitor species, the concentration of the inhibitor, H2O2 concentration and SiO2 concentration on material removal rate (MRR) was investigated. The results reveal that MRR is 13.1 nm/min when the slurry contains 1wt.% H2O2, 1wt.% SiO2, 1 wt.% citric acid, 1mM BTA and pH =9 and the down force was 1 psi. The influence of the BTA concentration on the corrosion on the surface of Os was analyzed using electrochemical analysis method; it was found that the maximum value of Ecorr appeared when the BTA concentration was 1.5 mm

Ruthenium (Ru) and ruthernium alloys may be utilized as new copper barrier materials in copper interconnects of ultra-large scale integration (ULSI), and chemical mechanical polish (CMP) can be applied in planarization for ULSI production. In this paper, CMP experiments were done on high purity Ru by using home-made slurry, the effect of oxidizer, complexing agent, polishing downforce, pH value, inhibitor species and inhibitor concentration on the material removal rate (MRR) was investigated. The results revealed that MRR can reach 8.7 nm/min under the following conditions: the main constituents in slurry were 1 wt.% SiO2, 1 wt.% (NH4)2S2O8, 1 wt.% tartaric acid and 3 mM imidazole, the pH value was 8.0, the down force was 2.5 psi (17.24 kPa); the roughness Ra was 7.6 nm under these conditions.

We recruited 805 patients with suspicious pulmonary masses that were identified finally as lung cancer or benign pulmonary masses. The serum levels of four tumor markers, including squamous cell carcinoma antigen (SCC), carcinoembryonic antigen (CEA), cytokeratin 19 fragment antigen 21-1 (Cyfra21-1) and neuron specific enolase (NSE) were tested for every patient. Though receiver operating characteristic (ROC) curves indicated unsatisfactory diagnostic power of those four tumor markers for lung cancer, 37.3% of early-staged lung cancer could be diagnosed just on the combination assays of the four tumor markers, under adjusted cut-off values through our statistical analysis retrospectively.