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Photocatalytic covalent organic frameworks (COFs) are popular in the field of biomedical materials and also have potential as antimicrobial materials. Herein, a boron-based COF was used in antibacterial applications innovatively. The results of this study suggested that COF-1, the earliest boroxine COF, could produce a variety of reactive oxygen species (ROS) under visible light irradiation. In order to explore more applications of COF-1, antibacterial tests were carried out based on the above results. The test results showed that the material displayed an obvious bactericidal effect on

Post-synthetic modification (PSM) is a prevalent and powerful strategy to introduce desired functionalities into covalent organic frameworks (COFs) for functional products, expediting their applications vastly. Herein, we demonstrate a PSM strategy for functionalizing brominated COFs via the well-developed Suzuki-Miyaura cross-coupling. By this, a variety of functionalities were installed into COFs efficiently, while the crystallinity and porosity of COFs was well-retained. As a proof-of-concept, BrCOF-2 was modified with trifluoromethyl groups to produce a SF6 adsorbent with remarkably enhanced properties. This facile and versatile approach opens a new door for the synthesis of functional COFs, and greatly expands the scope of their structural design aiming for various properties and applications.

Background: Cyclocodon lancifolius (Roxb.) Kurz is a perennial medicinal and edible plant with a huge potential economic value. The wild resources of this plant are gradually scarce by the serious destruction of the habitat and the limitations of sexual reproduction. This is the first attempt to establish an in vitro reproductive system for the species. Hypothesis: The suitable plant regulator types and its mass concentration range, combined with the explants, can induce the development of plants at various stages. We expected to establish an in vitro regeneration system of C. lancifolius based on these factors. Species studied: Cyclocodon lancifolius Study site and years of study: Yunnan Breeding and Cultivation Research and Development Center of Endangered and Daodi Chinese Medicinal Materials, Yunnan University of Chinese Medicine, from 2017 to 2019. Methods: The plant regeneration of C. lancifolius was established by single factor, L9 (34) orthogonal and complete combination experiments. Results: Stem segments were the best explants for callus induction on MS medium containing 0.05 mg·L-1 KT, 0.5 mg·L-1 6-BA and 0.5 mg·L-1 NAA. MS medium with 0.2 mg·L-1 TDZ and MS medium were used alternately as the culture method to conduct differentiation and proliferation of adventitious shoot. The optimal protocol for the rooting was MS medium combined with 0.1 mg·L-1 6-BA and 1.0 mg·L-1 NAA. Conclusions: A rapid propagation system of C. lancifolius was established which provided a possible solution for the protection of wild resources and artificial cultivation.

Layered/two-dimensional covalent organic frameworks (2D COF) are crystalline porous materials composed of light elements linked by strong covalent bonds. Interlayer force is one of the main factors directing the formation of a stacked layer structure, which plays a vital role in the stability, crystallinity, and porosity of layered COFs. The as-developed new way to modulate the interlayer force of imine-linked 2D TAPB-PDA-COF (TAPB = 1,3,5-tris(4-aminophenyl)benzene, PDA = terephthaldehyde) by only adjusting the pH of the solution. At alkaline and neutral pH, the pore size of the COF decreases from 34 Å due to the turbostratic effect. Under highly acidic conditions (pH 1), TAPB-PDA-COF shows a faster and stronger turbostratic effect, thus causing the 2D structure to exfoliate. This yields bulk quantities of an exfoliated few/single-layer 2D COF, which was well dispersed and displayed a clear Tyndall effect (TE). Furthermore, nanopipette-based electrochemical testing also confirms the slipping of layers with increase towards acidic pH. A model of pH-dependent layer slipping of TAPB-PDA-COF was proposed. This controllable pH-dependent change in the layer structure may open a new door for potential applications in controlled gas adsorption/desorption and drug loading/releasing.

The polysulfide shuttling and sluggish redox kinetics, due to the notorious adsorption-catalysis underperformance, are the ultimate obstacles of the practical application of lithium-sulfur (Li-S) batteries. Conventional carbon-based and transition metal compound-based material solutions generally suffer from poor catalysis and adsorption, respectively, despite the performance gain in terms of the other. Herein, we have enhanced polysulfide adsorption-catalytic capability and protected the Li anode using a complementary bimetallic carbide electrocatalyst, Co3Mo3C, modified commercial separator. With this demonstration, the potentials of bimetal compounds, which have been well recognized in other environmental catalysis, are also extended to Li-S batteries. Coupled with this modified separator, a simple cathode (S/Super P composite) can deliver high sulfur utilization, high rate performance, and excellent cycle stability with a low capacity decay rate of ∼0.034% per cycle at 1 C up to 1000 cycles. Even at a high S-loading of 8.0 mg cm−2 with electrolyte/sulfur ratio=6 mL g−1, the cathode still exhibits high areal capacity of ∼6.8 mA h cm−2. The experimental analysis and the first principles calculations proved that the bimetallic carbide Co3Mo3C provides more binding sites for adsorbing polysulfides and catalyzing the multiphase conversion of sulfur/polysulfide/sulfide than monometallic carbide Mo2C. Moreover, the modified separator can be reutilized with comparable electrochemical performance. We also showed other bimetallic carbides with similar catalytic effects on Li S batteries and this material family has great promise in different energy electrocatalytic systems.

Bionic electronic synapses with weight-modulation properties are promising alternative candidates when compared with traditional CMOS based neuromorphic hardware when building at-scale neural networks for efficient neuromorphic computing. In this Letter, due to the partial polarisation switching of multi-domain properties in polycrystalline Zr-doped HfO2 (HZO) ferroelectric materials, a capacitor-based bionic synapse was proposed, which showed multi-level capacitance modulation characteristics. By switching the voltage-controlled polarisation, the capacitance was gradually modulated via the variation of net polarisation vectors in the HZO layer. The potentiation and depression properties can be achieved with better linearity, symmetry and multiple states. This Letter laid the groundwork for realising the high-density integration neuromorphic computing system by using ferroelectric capacitors as the bionic synapse.

In this work, we investigated the mixing of different constituent layers in an HfO2 dielectric oxide semiconductor by performing transmission electron microscope (TEM) characterizations. Energy dispersive X-ray (EDX) line scanning indicated that the elemental distribution extended into the substrates and the migration was bidirectional. The migration distance was at the same order of magnitude as the simulation result. The formation of new chemical bonds at the migration endpoint resulted in complex surface conditions. Hafnium oxide is considered a promising material for microelectronic devices with a size of less than 20 nm and has promising potential applications in aerospace engineering; therefore, the surface conditions determine the performance of the devices.

As a reactive oxygen species (ROS)-promoted disease, acute kidney injury (AKI) is associated with high mortality and morbidity, but no effective pharmacological treatment is available. Kidney-targeted and ROS-reactive antioxidants are in urgent demand for AKI treatment. A promising nanotechnology-based strategy for targeting renal tubules offers new perspectives for AKI treatment but remains challenging because of the glomerular filtration barrier, which requires ultrasmall-sized therapeutics for penetration and filtration. Here, we fabricated four potential antioxidative carbon nanodots (CNDs) with ultrasmall size. After balancing the antioxidant properties and biocompatibility, m-phenylenediamine-based CNDs (PDA-CNDs) were chosen for further research. PDA-CNDs demonstrated remarkable antioxidant properties for scavenging multiple toxic free radicals, enabling efficient protection of cells under various oxidative stresses in vitro. Moreover, fluorescence imaging revealed that PDA-CNDs preferentially accumulated in the injured kidney of mice with ischemia-reperfusion (IR)-induced AKI. Blood renal function tests and kidney tissue staining revealed the therapeutic efficacy of PDA-CNDs for AKI in both the murine IR-induced AKI model and cisplatin-induced AKI model. Collectively, this is the first study revealing that specific rationally designed CNDs could be a promising pharmacological treatment for AKI induced by ROS.

Aluminum-ion batteries (AIBs) are regarded as one of the most promising types of energy storage device in light of the safety, natural abundance, and electrochemical properties of aluminum. However, the rate capabilities of AIBs are limited owing to the sluggish kinetics of chloroaluminate anions. In this study, a covalent organic framework (COF) is adopted as the cathode material in AIBs. Theoretical and experimental results suggest that the COFs allow fast anion diffusion and intercalation without structure collapse, owing to the robust frameworks and the hierarchical pores with a large specific surface area of 1794 m2 g-1 . The resultant AIB exhibits remarkable long-term stability, with a reversible discharge capacity of 150 mAh g-1 after 13 000 cycles at 2 A g-1 . It also shows an excellent rate capability of 113 mAh g-1 at 5 A g-1 . This work fully demonstrates the potential of COFs in the storage of chloroaluminate anions and other large-sized ions.

The rapid development of miniaturized and wearable electronics has stimulated growing needs for compatible miniaturized energy storage components. Owing to their unlimited lifetime and high-power density, miniaturized electrochemical capacitors (microsupercapacitors) are considered to be an attractive solution for the development of these microelectronics, but they often depend on the choice of electrode materials and fabrication protocols for scalable production. Recently, a new family of two-dimensional transition metal carbides, carbonitride and nitrides (referred to as MXenes) has shown great promise in advanced microsupercapacitors with high energy and power densities. This was achieved thanks to the high pseudocapacitance, metallic conductivity and ease of solution processing of MXene. In this review, recent progress on MXene synthesis, microstructure design, and fabrication strategies of MXene microsupercapacitors are discussed, and their electrochemical performance is summarized. Further, we briefly discuss the technical challenges and future directions.

Covalent organic frameworks (COFs) consist nanochannels that are fundamentally important for their application. Up to now, the effect of gas phase on COF nanochannels are hard to explore. Here, TAPB-PDA-COFs (triphenylbenzene-terephthaldehyde-COFs) was synthesized in situ at the tip of a theta micropipette. The COF-covered theta micropipette (CTP) create a stable gas-liquid interface inside the COF nanochannels, through which the humidity-modulated ion mass transfer in the COF nanochannels can be recorded by recording the current across the two channels of the theta micropipette. Results show that the humid air changes the mobility of the ions inside the COF nanochannels, which leads to the change of ionic current. Humid air showed different effects on the ion transfer depending on the solvent polarity index and vapor pressure. Current decreases linearly with the increase of relative humidity (RH) from 11% to 98%. The CTP was also mounted on the scanning electrochemical microscopy as a probe electrode for mapping micrometer-scale humidity distribution.

Three unprecedented 2D [4+3] covalent organic frameworks (TTCOF-1, TTCOF-2, and TTCOF-3) have been prepared by sub-stoichiometric condensation of tetratopic and tritopic monomers, overcoming the limitations of the design rules of conventional topologies. By reticulating the tetraphenylethylene (TPE)-based and triazine-based moieties into COF frameworks, novel electron donor-acceptor (D-A) type structures were obtained. These TTCOFs have good photocatalytic activity in aerobic C(sp3)–H bond functionalization and arylboronic acid oxidation driven by visible light, with yields up to 94%. This can expedite possibilities of COFs with new structural and topological complexities and can also expand the application of COF-based photocatalysis in synthetic chemistry.

The eye is the most important sensory organ of the human body, and the cornea and anterior chamber are very important components In surgeries like vision correction, it is necessary to know the accurate corneal thickness and anterior chamber depth of human eyes. Their accurate measurement cannot only provide a reference for doctors, but also provide a strong guarantee of surgical results. In order to achieve high-precision measurements of human corneal thickness and anterior chamber depth, we develop an equivalent human-eye optical system and a measurement method for the thickness. This method designs an equivalent double-membrane system to simplify the physiological structure of the cornea and anterior chamber of the human eye and irradiate the double-membrane system through laser. The reflected light returns to the laser cavity and the original light self-mixing interference, and a photodetector collects and processes the interference signals to obtain the corneal thickness and anterior chamber depth. The correctness of the theoretical calculations is verified by the experimental system, and the measurement accuracy can reach the micrometer level.

Here we prepare a hexagonal boron nitride (h-BN)–polyethylene oxide composite polymer electrolyte via a convenient casting method, which shows high mechanical strength. Meanwhile, the electrochemical properties (electrochemical window and lithium ion transference number) are enhanced but the ionic conductivity of the h-BN composite electrolyte is decreased after adding h-BN. Density functional theory (DFT) calculation results show that a stronger binding effect is observed between TFSI− and BN, compared to that between Li+ and BN. Molecular dynamics (MD) simulations are also utilized to study the mechanism behind the enhanced Li ion diffusion by h-BN addition. Li+ diffusion in PEO/LiTFSI/BN is lower than that in the PEO/LiTFSI system, but the diffusion of TFSI− exhibits a more significant decline rate in the presence of BN. This indicates that the presence of BN suppresses anion motion and enhances selectivity in Li+ transport. Thus, the PEO/LiTFSI/h-BN composite electrolyte exhibits higher Li ion conductivity but lower anion diffusivity than the PEO/LiTFSI system. Hence the h-BN composite polymer electrolyte in a Li/Li symmetric battery provides a long cycling time of 430 h at 0.2 mA cm−2. A Li metal/LiFePO4 full battery with the PEO/LiTFSI/h-BN composite electrolyte also works more efficiently for long-term cycling (140 cycles) than a filler-free PEO based electrolyte (39 cycles).

Despite the growing research interest in highly bio-compatible carbon quantum dots (CQDs) for bioimaging, the synthesis of red-emitting CQDs with high photoluminescence efficiency and a sharp emission spectrum remains a formidable challenge in this field. Herein, we established a rational strategy for the synthesis of highly efficient ultra-narrow red-emitting CQDs by adopting a conjugated aromatic amine precursor (tris(4-aminophenyl)amine, TAPA) and introducing oxidative radical reagents. The resultant CQDs, T-CQDs featured red PL (615 ± 2 nm) with a high photoluminescence quantum yield (84 ± 5%) and a narrow emission linewidth (FWHM = 27 ± 1 nm), which together represented one of the highest levels in the field of CQDs so far. The T-CQDs were then further analyzed from the spectral and structural aspects, and the repeatability and universality of this strategy have also been discussed. Finally, the T-CQDs were successfully applied for both one-photon imaging and two-photon imaging with various bio-samples, both in vitro and in vivo.

Based on 22 nm ultrathin-body fully depleted silicon-on-insulator (UTB-FDSOI) transistors, we propose a novel structure of buried insulator layer aiming at total ionizing dose (TID) effects mitigation. Using technology computer-aided design (TCAD) tools, we focus on the influences of UTB-FDSOI devices with different structures and parameters on TID effects, such as buried oxide (BOX) layer thickness, buried Si3N4 layer, and electron traps. First, we construct four types of UTB-FDSOI N-type metal-oxide semiconductor (NMOS) devices numerically, in which the novel device features a buried silicon-oxide-nitride-oxide-silicon (SONOS) structure. Then, the transfer characteristics and trapped charge distribution of these devices are studied under different irradiation doses. It is known that a thinner BOX layer could lead to slighter TID effects, and the buried nitride layer and the electron traps could reduce the TID-induced leakage current ( $\text{I}_{\mathrm {off}}$ ). Employing these optimization structures for TID effects hardness, the innovative transistor shows much better resistance against TID effects compared to the conventional FDSOI transistors. In addition, the threshold voltage of the novel device could be increased by applying appropriate bias conditions, similar to those of programming SONOS memory, so that the $\text{I}_{\mathrm {off}}$ caused by TID irradiation further decreases. These results provide useful guidance for designers to achieve TID effects mitigation of SOI devices.

Potassium ion batteries (KIBs) are considered to be emerging and promising grid-scale energy storage devices owing to earth-abundant potassium resources. A pivotal limitation of KIBs is the sluggish diffusion kinetics and structural degradation resulting from huge mechanical stress during the repeated intercalation/deintercalation of K+ ions. Herein, we design open ZnSe/C nanocages composed of sub-10 nm nanoparticles with a multi-hierarchy stress-buffering effect for KIBs. The primary ultrafine nanoparticles, the secondary open structure and the tertiary hollow structure as stepwise stress-release hierarchies can effectively reduce diffusion-induced stresses and greatly enhance the structural integrity, which is further validated by detailed finite element simulation analysis. Meanwhile, the carbon layer can enhance the electronic conductivity and suppress the agglomeration of ZnSe nanoparticles, achieving high-rate performance. Owing to these merits, the open ZnSe/C nanocages deliver a high reversible capacity of 318 mA h g−1 at 50 mA g−1 as well as excellent cyclability of 189 mA h g−1 up to 1000 cycles at 500 mA g−1. This work provides new insight into excellent structural design with a multi-hierarchy stress-buffering effect for advanced potassium storage.

Metallic lithium batteries are holding great promises for revolutionizing the current energy storage technologies. However, the formation of dendrite-like morphology of lithium deposition caused by uneven distribution of Li+ might cause severe safety concerns of batteries. In this study, a polyoxometalate (POM) cluster, H5PMo10V2O40 (PMo10V2), is added to the conventional electrolyte that can construct a lithium-rich layer and inhibit the growth of Li dendrites effectively. The Li-rich layer can fill any lack of lithium ions on the surface of the metal anode, making the electric field strength consistent across the anode surface, thereby inhibiting the formation of lithium dendrites. Consequently, a significantly prolonged cyclic lifespan is obtained for both Li/Li symmetric cells and Li/LiCoO2 (Li/LCO) full cells. The cells with LCO positive maintains a high reversible specific capacity of 108.5 mAh g−1 after 300 cycles when electrolyte with PMo10V2 additive is used, compared to 31.5 mAh g−1 for the untreated electrolyte. The findings indicate that POMs endowed as “ionic sponge” can be widely deployed in lithium metal batteries.

Color-tunable ultralong phosphorescence is urgently desired in optoelectronic applications. Herein, we report a new type of full-color-tunable ultralong phosphorescence carbon dots (CDs) without matrix-assistance by a self-doping method under ambient conditions. The phosphorescence color can be rationally tuned from blue to red by changing the excitation wavelength from 310 to 440 nm. The CDs exhibit an ultralong lifetime of up to 1052.23 ms at 484 nm. From the experimental data, we speculate that the excitation-dependent multi-color phosphorescence is attributed to the presence of multiple emitting centers related to carbonyl units. Given the unique color-tunability of CDs, we demonstrate their potential applications in information encryption, light detection ranging from UV to visible light and LED devices. This finding not only takes a step towards the fundamental design of full-color emissive materials, but also provides a broader scope for the applications of phosphorescent materials.

OBJECTIVE: To investigate the impact of time interval from symptoms onset to vestibular rehabilitation on the recovery of patients in the acute phase of vestibular neuritis. METHODS: Thirty-one patients with vestibular neuritis treated in outpatient and inpatient settings from December 2019 to July 2021 were selected and randomly divided into vestibular rehabilitation group and general treatment group. The vestibular rehabilitation group was subdivided into early-intervention group (1-week after symptom onset) and late-intervention group (2-week after symptom onset) according to the interval from the onset to vestibular rehabilitation. The differences in DP, UW, VOR, DHI, BBS and SAS values at 1 month and 3 months after treatment were compared among early-intervention group(11 cases), late-intervention group (10 cases) and general treatment group(10 cases). RESULTS: For patients in the vestibular rehabilitation group and the general treatment group, DP, UW, VOR gain, DHI score and SAS score were significantly different after treatment (P < 0.05) and no significant difference was found in BBS score (P>0.05). Pairwise comparisons between early-intervention and late-intervention group showed that the DP, UW and VOR gain were significantly different (P < 0.05), while the score of DHI and SAS were not significantly different (P>0.05). CONCLUSION: Vestibular rehabilitation therapy can accelerate vestibular compensation, relieve vertigo symptoms and anxiety symptoms in patients with vestibular neuritis. It is better to be carried out within 1 week after symptom onset.

A new approach for the synthesis of the active barbatic acid has been achieved in eight steps with 22.3% total yield by using commercially available methyl atratate as starting material. This synthesis provides access to multi-gram quantities of barbatic acid with good purity for reference supplies and further analytical and toxicology investigations.

Supplemental Material for The analgesic effects of β-elemene in rats with neuropathic pain by inhibition of spinal astrocytic ERK activation by Li-Tian Ma, Yang Bai, Peng Cao, Kai-Xi Ren, Jing Chen, Ting Zhang, Bo-Yuan Fan, Yu Qiao, Hong-Yu Yan, Jing-Jie Wang, Yun-Qing Li and Jin Zheng in Molecular Pain

The influence of impurity doping on GaAs-based two-well resonant-phonon terahertz quantum cascade lasers is investigated theoretically, and efficient doping schemes are discussed. By using the rate equation model, the impacts of dopant amount, position, and distribution on the performance of a high-performance device is simulated focusing on a single module. The calculated optical gain is found to have a peak over the range of sheet doping density from 1.0 × 1010 to 1.0 × 1012 cm−2 in all eight doping conditions examined in this work. Among these patterns, the devices with the undoped condition and homogeneous-doping in phonon-wells mark high optical gain, and the latter is also resistant against the detuning of subband alignment due to band-bending under the high doping conditions. Furthermore, based on the simulation results, a modulation doping scheme whose active cores include both doped and undoped modules is suggested and discussed.

Brain-computer interface (BCI) can be used as a real-time bidirectional information gateway between the brain and machines. In particular, rapid progress in invasive BCI, propelled by recent developments in electrode materials, miniature and power-efficient electronics, and neural signal decoding technologies has attracted wide attention. In this review, we first introduce the concepts of neuronal signal decoding and encoding that are fundamental for information exchanges in BCI. Then, we review the history and recent advances in invasive BCI, particularly through studies using neural signals for controlling external devices on one hand, and modulating brain activity on the other hand. Specifically, regarding modulating brain activity, we focus on two types of techniques, applying electrical stimulation to cortical and deep brain tissues, respectively. Finally, we discuss the related ethical issues concerning the clinical application of this emerging technology.

Pore-structure design with increased ion-diffusion ability is usually regarded as an effective strategy to improve K-storage performance in hard carbon (HC). However, the relationship between porous structure and K

Currently, even though birefringent soft materials have attracted considerable attention for many sensors and optical devices, it is still difficult for most of them to achieve multiple responses. Herein, we have designed a multiple-responding birefringent elastomer with high birefringence but low modulus by using 2-phenoxy-ethanoacrylate (PHEA) as monomer and 4-cyano-4'pentylbiphenyl as solvent. The excellent transparency (~90%) exhibited by the designed birefringent elastomer allowed us to observe the change of interference color. The obtained birefringent elastomer not only can be used as a photoelastic strain sensor with high sensitivity and fast response but also show a very sensitive response to heat, particularly in the range of the human body temperature. More interestingly, it shows excellent dielectric properties with a strong correlation between the interference color and the applied electric field, which allows easily writing and erasing the encrypted information. These unique multi-signal response features of our obtained birefringent elastomer shed light on the multiple information encryptions, the anti-counterfeiting, and the multifunctional sensors.

There is no doubt that the wide application of COFs depends on the diversity and complexity of their structure and composition, as well as the feasibility and convenience of use. Herein, large area defect-free continuous functional material layers have been fabricated by compounding sub-stoichiometric tetratopic-tritopic covalent organic frameworks (TT-COFs) on graphene oxide (GO) via simply hot pressing. The one-step synthesis of TT-COFs with built-in formyl groups endowed the robust material layers with extraordinary host-guest interactions, so they can specifically reject cations dyes according to adsorption effect, molecular sieving and Donnan effect. Owing to the through-plane molecular transfer channels, large amounts of water molecules can pass through the internal channel rapidly. As a result, high rejection of 99.5% and large flux of 309.99 L·m

Owing to the scarcity of Pt, low-cost, stable, and efficient nonprecious metal-based electrocatalysts that can be applied in a wide pH range for the hydrogen evolution reaction (HER) are urgently required. Herein, a highly efficient and robust HER catalyst that is applicable at all pH values is fabricated, containing isolated Co-single atomic sites anchored in the self-supported WO

The attack of vertigo and balance disorder affects individual quality of life among all age, while brings high medical burden. Vestibular rehabilitation plays an important role in the treatment for balance disorder. Early active and systematic rehabilitation treatment will be more conducive to symptom relief, functional recovery, and prevent the occurrence of chronic vestibular syndrome. There were no criteria for the methods, influencing factors and evaluation of vestibular rehabilitation in the treatment of peripheral vestibular vertigo yet, and the clinical application is diversified. This paper reviewed and summarized the related studies of vestibular rehabilitation in peripheral vestibular vertigo in recent years.