Covalent Bonding of MXene/COF Heterojunction for Ultralong Cycling Li-Ion Battery Electrodes.

Covalent organic frameworks (COFs) have emerged as promising renewable electrode materials for LIBs and gained significant attention, but their capacity has been limited by the densely packed 2D layer structures, low active site availability, and poor electronic conductivity. Combining COFs with high-conductivity MXenes is an effective strategy to enhance their electrochemical performance. Nevertheless, simply gluing them without conformal growth and covalent linkage restricts the number of redox-active sites and the structural stability of the composite. Therefore, in this study, a covalently assembled 3D COF on Ti3C2 MXenes (Ti3C2@COF) is synthesized and serves as an ultralong cycling electrode material for LIBs. Due to the covalent bonding between the COF and Ti3C2, the Ti3C2@COF composite exhibits excellent stability, good conductivity, and a unique 3D cavity structure that enables stable Li+ storage and rapid ion transport. As a result, the Ti3C2-supported 3D COF nanosheets deliver a high specific capacity of 490 mAh g-1 at 0.1 A g-1, along with an ultralong cyclability of 10,000 cycles at 1 A g-1. This work may inspire a wide range of 3D COF designs for high-performance electrode materials.

Subconjunctival injection of rapamycin-loaded polymeric microparticles for effective suppression of noninfectious uveitis in rats.

Noninfective uveitis is a major cause of vision impairment, and corticosteroid medication is a mainstay clinical strategy that causes severe side effects. Rapamycin (RAPA), a potent immunomodulator, is a promising treatment for noninfective uveitis. However, because high and frequent dosages are required, it is a great challenge to implement its clinical translation for noninfective uveitis therapy owing to its serious toxicity. In the present study, we engineered an injectable microparticulate drug delivery system based on biodegradable block polymers (i.e., polycaprolactone-poly (ethylene glycol)-polycaprolactone, PCEC) for efficient ocular delivery of RAPA via a subconjunctival injection route and investigated its therapeutic efficacy in an experimental autoimmune uveitis (EAU) rat model. RAPA-PCEC microparticles were fabricated using the emulsion-evaporation method and thoroughly characterized using scanning electron microscopy, fourier transform infrared spectroscopy, X-ray diffraction, and differential scanning calorimetry. The formed microparticles exhibited slow in vitro degradation over 28 days, and provided both in vitro and in vivo sustained release of RAPA over 4 weeks. Additionally, a single subconjunctival injection of PCEC microparticles resulted in high ocular tolerance. More importantly, subconjunctival injection of RAPA-PCEC microparticles significantly attenuated the clinical signs of EAU in a dose-dependent manner by reducing inflammatory cell infiltration (i.e., CD45+ cells and Th17 cells) and inhibiting microglial activation. Overall, this injectable microparticulate system may be promising vehicle for intraocular delivery of RAPA for the treatment of noninfective uveitis.

Nano Self-Assemblies of Caffeic Acid-Fibronectin Mimic a Peptide Conjugate for the Treatment of Corneal Epithelial Injury.

Rapid corneal re-epithelialization is important for corneal wound healing. Corneal epithelial cell motility and oxidative stress are important targets for therapeutic intervention. In this study, we covalently conjugated the antioxidant caffeic acid (CA) with a bioactive peptide sequence (PHSRN) to generate a CA-PHSRN amphiphile, which was formulated into nanoparticular eye drops with an average size of 43.21 ± 16 nm. CA-PHSRN caused minimal cytotoxicity against human corneal epithelial cells (HCECs) and RAW264.7 cells, exhibited an excellent free radical scavenging ability, and remarkably attenuated reactive oxygen species (ROS) levels in H2O2-stimulated HCECs. The antioxidant and anti-inflammatory activities of CA-PHSRN were assessed in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The results show that CA-PHSRN treatment effectively prevented LPS-induced DNA damage and significantly reduced the levels of LPS-induced pro-inflammatory cytochemokines (i.e., iNOS, NO, TNF-α, IL-6, and COX-2) in a dose-dependent manner. Moreover, using a rabbit corneal epithelial ex vivo migration assay, we demonstrated that the proposed CA-PHSRN accelerated corneal epithelial cell migration and exhibited high ocular tolerance and ocular bioavailability after topical instillation. Taken together, the proposed CA-PHSRN nanoparticular eye drops are a promising therapeutic formulation for the treatment of corneal epithelial injury.

Ultrasensitive Bio-H2S Gas Sensor Based on Cu2O-MWCNT Heterostructures.

Developing a respiratory analysis disease diagnosis platform for the H2S biomarker has great significance for the real-time detection of various diseases. However, achieving highly sensitive and rapid detection of H2S gas at the parts per billion level at low temperatures is one of the most critical challenges for developing portable exhaled gas sensors. Herein, Cu2O-multiwalled carbon nanotube (MWCNT) heterostructures with excellent gas sensitivity to H2S at room temperature and a lower temperature were successfully synthesized by a facile two-dimensional (2D) electrodeposition in situ assembly method. The combination of Cu2O and MWCNTs via the principle of optimal conductance growth not only reduced the initial resistance of the material but also provided an ideal interfacial barrier structure. Compared to the response of the pure Cu2O sensor, that of the Cu2O-MWCNT sensor to 1 ppm of H2S increased nearly 800 times at room temperature, and the response time decreased by more than 500 s. In addition to the excellent sensitivity with detection limits as low as 1 ppb, the Cu2O-MWCNT sensor was extremely selective with low-temperature adaptability. The sensor had a response value of 80.6 to 0.1 ppm of H2S at -10 °C, which is difficult to achieve with sensors based on oxygen adsorption/desorption mechanisms. The sensor was used for the detection of real oral exhaled breath, confirming its feasibility as a real-time disease monitoring sensor. The Cu2O-MWCNT heterostructures maximized the advantages of the individual components and laid the experimental foundation for future applications of highly sensitive portable breath analysis platforms for monitoring H2S.

Cu2O/Co3O4 nanoarrays for rapid quantitative analysis of hydrogen sulfide in blood.

2D heterostructure nanoarrays have emerged as a promising sensing material for rapid disease detection applications. In this study, a bio-H2S sensor based on Cu2O/Co3O4 nanoarrays was proposed, the controllable preparation of the nanoarrays being achieved by exploring the experimental parameters of the 2D electrodeposition in situ assembly process. The nanoarrays were designed as a multi-barrier system with strict periodicity and long-range order. Based on the interfacial conductance modulation and vulcanization reaction of Cu2O and Co3O4, the sensor exhibited superior sensitivity, selectivity, and stability to H2S in human blood. In addition, the sensor exhibited a reasonable response to 0.1 µmol L-1 Na2S solution, indicating that it had a low detection limit for practical applications. Moreover, first-principles calculations were performed to study changes in the heterointerface during the sensing process and the mechanism of rapid response of the sensor. This work demonstrated the reliability of Cu2O/Co3O4 nanoarrays applied in portable sensors for the rapid detection of bio-H2S.

Basal Planes Unlocking and Interlayer Engineering Endows Proton Doped-MoO2.8F0.2 with Fast and Stable Magnesium Storage.

Molybdenum trioxide has served as a promising cathode material of rechargeable magnesium batteries (RMBs), because of its rich valence states and high theoretical capacity; yet, it still suffers from sluggish (de)intercalation kinetics and inreversible structure change for highly polarized Mg2+ in the interlayer and intralayer of structure. Herein, F- substitutional and H+ interstitial doping is proposed for α-MoO3 materials (denoted HMoOF) by the intralayer/interlayer engineering strategy to boost the performance of RMBs. F- substitutional doping generates molybdenum vacancies along the Mo-O-□ or Mo-F-□ configurations (where □ represents the cationic vacancy) for unlocking the inactive basal plane of the layered crystal structure, and it further accelerates Mg2+ diffusion along the b-axis. Interstitial-doped H+ can expand interlayer spacing for reducing Mg2+ energy barrier along the ac plane and serve as a "pillar" to stabilize the interlayer structure. Moreover, anion and cation dual doping trigger shallow impurity levels (acceptors levels and donor levels), which helps to easily acquire the electrons from the valence band and donate the electrons to the conduction band. Consequently, the HMoOF electrode exhibits a high reversible capacity (241 mA h g-1 at 0.1 A g-1), an excellent rate capability (137.4 mAh g-1 at 2 A g-1), and a long cycling stability (capacity retention of 98% after 800 cycles at 1 A g-1) in RMBs. This work affords meaningful insights in layered materials for developing high-kinetics and long-life RMBs.

Magnetic-Field-Enhanced H2S Sensitivity of Cu2O/NiO Heterostructure Ordered Nanoarrays.

Magnetism is a promising external intervention for gas sensitivity based on a heterogeneous interfacial structure caused by the regulation of the heterogeneous interface conductivity and the surface oxygen adsorption. In this study, Cu2O/NiO heterostructure-ordered nanoarrays were prepared with a two-dimensional (2D) electrodeposition in situ assembly method for H2S gas detection at room temperature under the action of a magnetic field. The nanoarrays were multibarrier structures with a strictly periodic structure that was greater than hundreds of microns in size. The experimental data confirmed that the response of 50 ppm of H2S based on the nanoarrays was improved by nearly 61% with a relatively weak magnetic field. Particularly at a low concentration (≤20 ppm), the effect of the magnetic field enhancement on the sensitivity was more obvious. We attributed the enhancement of the gas sensitivity with the magnetic field to the regulation of the Cu2O-NiO interface conductance and the surface oxygen adsorption. This study demonstrated that a magnetic field could significantly enhance the gas sensitivity based on heterostructures. Results of this study provide an important reference for the application of magnetism in gas detection and the design of new gas-sensitive materials.

Redox-activity of polydopamine for ultrafast preparation of self-healing and adhesive hydrogels.

The high adhesive property of polydopamine (PDA) has spurred various hydrogels for biological and medical applications. Herein, a dual-catalytic redox system was constructed by using the inner dynamic redox-activity of PDA and free radical initiator ammonium persulfate (APS) to initiate the polymerization of acrylic acid (AA) monomer to obtain Fe-PDA hydrogels within 2 h at room temperature. Fe-PDA NPs functions as both initiator to activate APS to generate free radicals and promotes the formation of the hydrogel and dynamic cross-linking mediator between the polymer chains. The tensile strength and ductility of the obtained hydrogels vary with the content of Fe-PDA NPs. Hydrogel with 0.15 wt% of Fe-PDA NPs has the highest tensile strength (~0.62 MPa) and hydrogel with 0.6 wt% of Fe-PDA NPs has the highest elongation, about ~650%. The introduction of PDA NPs imparts PAA hydrogel with reproducible adhesive properties and self-healing ability. The doped iron ion further endows hydrogel enhanced photothermal properties (up to 160 â„ƒ with 808 nm laser irradiation for 120 s) and conductivity.

Dual-Specificity Phosphatase 9 Regulates Cellular Proliferation and Predicts Recurrence After Surgery in Hepatocellular Carcinoma.

Hepatocellular carcinoma (CC) is a common and deadly cancer with complex molecular pathogenesis. Little is known about dual-specificity phosphatases (DUSPs) in HCC. We investigated DUSP9 expression in human HCC, associations between DUSP9 and patient outcomes, and effects of altered DUSP9 expression on HCC biology. We studied public data sets as well as 196 patients at our institution who had HCC resections. Quantitative real-time reverse transcription polymerase chain reaction and western blot demonstrated that DUSP9 expression was increased >10-fold in HCC compared to adjacent liver and healthy controls (P = 0.005). Kaplan-Meier and multivariable regression analyses revealed that higher DUSP9 expression was associated with shorter disease-free survival (high DUSP9, 1.6; 95% confidence interval, 0.9-2.3 vs. low DUSP9, 3.4; 95% confidence interval, 1.8-5.0 years; P = 0.04) and increased risk of recurrence (hazard ratio 1.55; 95% confidence interval, 1.01-2.67; P = 0.05) after resection. DUSP9 complementary DNA (cDNA) was cloned using rapid amplification of cDNA ends, revealing two DUSP9 isoforms in human HCC cells. Studies of transcriptional regulation using promoter-luciferase reporter constructs suggested that DUSP9 transcription is regulated by E26 transformation-specific transcription factors. Proliferation of hepatic cells in vitro was enhanced by lentiviral-mediated overexpression of DUSP9. In contrast, DUSP9 knockout HCC cells generated using clustered regularly interspaced short palindromic repeats (CRISPR) demonstrated decreased HCC proliferation and doxorubicin resistance in vitro and impaired xenograft growth in vivo. RNA sequencing, gene set enrichment, and network/pathway analysis revealed that DUSP9 knockout is associated with activation of protein kinase activity and apoptosis. Conclusion: DUSP9 regulates cell proliferation and predicts recurrence after surgery in HCC. DUSP9 may represent a novel prognostic candidate and therapeutic target. Additional studies are warranted to further explore the role and regulation of DUSP9 in HCC.

Pancake-Like MOF Solid-State Electrolytes with Fast Ion Migration for High-Performance Sodium Battery.

Solid-state electrolyte (SSE) of the sodium-ion battery have attracted tremendous attention in the next generation energy storage materials on account of their wide electrochemical window and thermal stability. However, the high interfacial impedance, low ion transference number and complex preparation process restrict the application of SSE. Herein, inspired by the excellent sieving function and high specific surface area of red blood cells, we obtained a solid-like electrolyte (SLE) based on the combination of the pancake-like metal-organic framework (MOF) with liquid electrolyte, possessing a high ionic conductivity of 6.60 × 10-4 S cm-1, and excellent sodium metal compatibility. In addition, we investigated the ion restriction effect of MOF's apertures size and special functional groups, and the ion transference number increased from 0.16 to 0.33. Finally, the assembled Na0.44MnO2//SLE//Na full batteries showed no obvious capacity decrease after 160 cycles. This material design of SLE in our work is an important key to obtain fast ion migration SLE for high-performance sodium-ion batteries.

Open-Structured Nanotubes with Three-Dimensional Ion-Accessible Pathways for Enhanced Li+ Conductivity in Composite Solid Electrolytes.

Composite solid electrolytes (CSEs) hold great promise toward safe lithium metal batteries with high energy density, due to integration of the merits of polymer matrixes and fillers. Rational design of filler nanostructures has attracted increasing attention for improving the ionic transport of CSEs in solid batteries. In this work, we fabricated open-structured Li0.33La0.557TiO3 (LLTO) nanotubes (NTs) as ion-conductive fillers in CSEs by a gradient electrospinning method for the first time. Different from nanoparticles (NPs) and nanowires (NWs), our nanotubes are composed of connected small NPs, which offer three-dimensional (3D) Li+-accessible pathways, large polymer/filler interfacial ionic conduction regions, and enhanced wettability against the polymer matrix. As a result, the solid electrolytes based on LLTO NTs and polyacrylonitrile (PAN) can display a high ionic conductivity of up to 3.6 × 10-4 S cm-1 and a wide electrochemical window of 5 V at room temperature (RT). Furthermore, Li-Li symmetric cells using the LLTO NTs/PAN CSE can work stably over 1000 h with a polarization of 20 mV. LiFePO4-Li full cells exhibit a high capacity of 142.5 mAh g-1 with a capacity retention of 90% at 0.5 C after 100 cycles. All of these results demonstrate that the design of open-structured nanotubes as fillers is a promising strategy for high-performance solid electrolytes.

Electron cloud migration effect-induced lithiophobicity/lithiophilicity transformation for dendrite-free lithium metal anodes.

Enabling stable lithium metal anodes is significant for developing electrochemical energy storage systems with higher energy density. However, safety hazards, infinite volume expansion, and low coulombic efficiency (CE) of lithium metal anodes always hinder their practical application. Herein, a nano-thickness lithiophilic Cu-Ni bimetallic coating was synthesized to prepare dendrite-free lithium metal anodes. The electron cloud migration effect caused by the different electronegativities of Cu and Ni can achieve lithiophobicity/lithiophilicity transformation and thus promote uniform Li deposition/dissolution. By changing the ratio of Cu to Ni, the electron cloud migration can be reasonably adjusted for obtaining dendrite-free lithium anodes. As a result, the as-obtained Cu-Ni bimetallic coating is able to guarantee dendrite-free lithium metal anodes with a stable long cycling time (>1500 hours) and a small voltage hysteresis (∼26 mV). In addition, full cells with LiFePO4 as a cathode present excellent cycling stability and high coulombic efficiency. This work can open a new avenue for optimizing the lithiophilicity of materials and realizing dendrite-free anodes.

Natural-Killer-Cell-Inspired Nanorobots with Aggregation-Induced Emission Characteristics for Near-Infrared-II Fluorescence-Guided Glioma Theranostics.

Nature has always inspired robotic designs and concepts. It is conceivable that biomimic nanorobots will soon play a prominent role in medicine. The "Terminator" in the science fiction film is a cybernetic organism with living tissue over a metal endoskeleton, which inspired us to develop natural-killer-cell-mimic nanorobots with aggregation-induced emission (AIE) characteristics (NK@AIEdots) by coating a natural kill cell membrane on an AIE-active polymeric endoskeleton, PBPTV, a highly bright NIR-II AIE-active conjugated polymer. Owing to the AIE and soft-matter characteristics of PBPTV, as-prepared NK@AIEdots maintained a superior NIR-II brightness (quantum yield ∼7.9% in water) and good biocompatibility. Besides, they can serve as a tight junction (TJ) modulator to trigger an intracellular signaling cascade, causing TJ disruption and actin cytoskeleton reorganization to form an intercellular "green channel" to help them to cross the blood-brain barrier (BBB) silently. Furthermore, they can initiatively accumulate in glioblastoma cells in the complex brain matrix for high-contrast and through-skull tumor imaging. The tumor growth was also greatly inhibited by these NK@AIEdots under the NIR light illumination. As far as we know, the quantum yield of PBPTV is the highest among the existing NIR-II luminescent conjugated polymers. Besides, the NK-cell biomimetic nanorobots showed great potential for BBB-crossing active delivery.

Rational Design of Ion Transport Paths at the Interface of Metal-Organic Framework Modified Solid Electrolyte.

Solid-state lithium batteries have attracted great attention owing to their potential advantages in safety and energy density. Among various solid electrolytes, solid polymer electrolyte is promising due to its good viscoelasticity, lightweight, and low-cost processing. However, key issues of solid polymer electrolyte include poor ionic conductivity and low Li+ transference number, which limit its practical application. Herein, a new-type of ultraviolet cross-linked composite solid electrolyte (C-CSE), composed of ZIF-based ionic conductor (named ZIL) and polymer, is designed with enhanced ion transport. The ZIL is composed of ZIF-8 and ionic liquid, which can provide C-CSE with fast ion transport paths. Moreover, the proper pore size of ZIF-8 can restrict the migration of embedded ionic liquid and thus construct a solid-liquid transport interface between polymer chains and ZIF-8, which could achieve fast ion transport. In addition, ultraviolet irradiation can decrease the crystallization of C-CSE and thus increase the amorphous region. Consequently, the C-CSE show excellent electrochemical performance including high ionic conductivity of 0.426 mS cm-1 at 30 °C, high Li+ transference number of 0.67, and good Li|Li compatibility cycle over 1040 h. Experimental and computational results indicate that diffusion energy barrier of Li+ through ZIF-8 is smaller than that of polymer chains, which reveals a new Li+ transport mechanism between polymer chains and ZIL, from "chain-chain-chain" to "chain-ZIL-chain". This work demonstrates rational design of ion transport paths at the interface of solid electrolyte could facilitate the development of solid-state lithium batteries as a promising novel strategy.

Corticosteroid therapy in pneumonia from swine-origin influenza A (H1N1) in China.

The first three cases of confirmed infection with the virus in China were documented between May 10 and May 15, 2009. Although the clinical characteristics of the H1N1 pneumonia were described in clinical reports, the therapy has few been described. Therefore, we report our experiences of 53 cases of the H1N1 pneumonia with treatment. We describe clinical characteristic of 53 patients who were hospitalized for laboratory-confirmed H1N1 pneumonia at the 2nd Clinical College of Harbin Medical University. In addition, we measure the role of corticosteroid, mechanical ventilation, and non-corticosteroid antiviral therapy in the management of pneumonia patients with novel H1N1 infection. Real-time reverse-transcriptase-polymerase chain (RT-PCR) testing was used to confirm infection. The outcome of therapy was compared in scores of PaO2 and CT. The data was statistical analyzed by the Shapiro-Wilk, anova, Student-Newman-Keuls Test, and Kruskal-Wallis Test. The most common symptoms were dyspnea. In moderate ill patients, the changes in the increased PaO2 were lower in the non-corticosteroid antiviral therapy group than in the combination of corticosteroid and non-corticosteroid antiviral therapy after 5 days' therapy. The therapy protocol of non-corticosteriod + mechanical ventilation played important role in the recovery of severe ill patients.

A facile soft template method to synthesize hollow carbon and MnO x composite particles for effective methylene blue degradation.

Hollow carbon and MnO x composite particles (HC-Mn) were fabricated by using polyacrylic acid (PAA) and Mn ion co-assembled colloids as the soft template and resorcinol formaldehyde resin (RF) as the carbon source. The formation process was well studied and a plausible formation mechanism was proposed. The Mn ions played two key roles in the synthesis: first, they promoted the aggregation of the PAA molecules, thus forming the PAA-Mn colloids in solution with high water content, which were suitable for the subsequent RF coating. Secondly, considerable Mn ions were retained after template removal, which were transformed into MnO x particles simultaneously during carbonization. This approach was facile and effective and the as-prepared HC-Mn showed superior catalytic activity toward methylene blue (MB) degradation.

A highly selective long-wavelength fluorescent probe for hydrazine and its application in living cell imaging.

A highly selective long-wavelength turn-on fluorescent probe has been developed for the detection of N2H4. The probe was prepared by conjugation the tricyanofuran-based D-π-A system with a recognizing moiety of acetyl group. In the presence of N2H4, the probe can be effectively hydrazinolysized and produce a turn-on fluorescent emission at 610nm as well as a large red-shift in the absorption spectrum corresponding to a color change from yellow to blue. The sensing mechanism was confirmed by HPLC, MS, UV-vis, emission spectroscopic and theoretical calculation studies. The probe displayed high selectivity and sensitivity for N2H4 with a LOD (limit of detection) of 0.16µM. Moreover, the probe was successfully utilized for the detection of hydrazine in living cells.

Extremely Sensitive Dependence of SnOx Film Properties on Sputtering Power.

An extremely sensitive dependence of the electronic properties of SnOx film on sputtering deposition power is discovered experimentally. The carrier transport sharply switches from n-type to p-type when the sputtering power increases by less than 2%. The best n-type carrier transport behavior is observed in thin-film transistors (TFTs) produced at a sputtering power just below a critical value (120 W). In contrast, at just above the critical sputtering power, the p-type behavior is found to be the best with the TFTs showing the highest on/off ratio of 1.79 × 104 and the best subthreshold swing among all the sputtering powers that we have tested. A further increase in the sputtering power by only a few percent results in a drastic drop in on/off ratio by more than one order of magnitude. Scanning electron micrographs, x-ray diffraction spectra, x-ray photoelectron spectroscopy, as well as TFT output and transfer characteristics are analyzed. Our studies suggest that the sputtering power critically affects the stoichiometry of the SnOx film.