Oral mucosal disease recognition based on dynamic self-attention and feature discriminant loss.

OBJECTIVES: To develop a dynamic self-attention and feature discrimination loss function (DSDF) model for identifying oral mucosal diseases presented to solve the problems of data imbalance, complex image background, and high similarity and difference of visual characteristics among different types of lesion areas. METHODS: In DSDF, dynamic self-attention network can fully mine the context information between adjacent areas, improve the visual representation of the network, and promote the network model to learn and locate the image area of interest. Then, the feature discrimination loss function is used to constrain the diversity of channel characteristics, so as to enhance the feature discrimination ability of local similar areas. RESULTS: The experimental results show that the recognition accuracy of the proposed method for oral mucosal disease is the highest at 91.16%, and is about 6% ahead of other advanced methods. In addition, DSDF has recall of 90.87% and F1 of 90.60%. CONCLUSIONS: Convolutional neural networks can effectively capture the visual features of the oral mucosal disease lesions, and the distinguished visual features of different oral lesions can be extracted better using dynamic self-attention and feature discrimination loss function, which is conducive to the auxiliary diagnosis of oral mucosal diseases.

Fast Lithium Ion Transport Pathways Constructed by Two-Dimensional Boron Nitride Nanoflakes in Quasi-Solid-State Polymer Electrolyte.

Quasi-solid-state electrolytes (QSSEs) are gaining huge popularity because of their significantly improved safety performance over nonaqueous liquid electrolytes and superior process adaptability over all-solid-state electrolytes. However, because of the existence of liquid molecules, QSSEs typically have low lithium ion transference numbers and compromised thermal stability. In this work, we present the fabrication of a well-rounded QSSE by introducing hexagonal boron nitride nanoflakes (BNNFs) as an inorganic filler in a poly(vinylene carbonate) matrix. BNNFs, in contrast to most inorganic fillers used as anion trappers, are used to build fast lithium ion transport pathways directly on their two-dimensional surfaces. We confirm the attractive coupling between lithium ions and BNNFs, and we confirm that with the help of BNNFs, lithium ions can migrate with less damping and a lower transport energy barrier. As a result, the designed electrolyte exhibits good ion transportability, promoted fire retardancy, and good compatibility with lithium metal anodes and commercial cathodes.

Ultrasmooth and Dense Lithium Deposition Toward High-Performance Lithium-Metal Batteries.

Lithium (Li)-metal batteries (LMBs) with stable solid electrolyte interphase (SEI) and dendrite-free formation have great potential in next-generation energy storage devices. Here, vertically aligned 3D Cu2 S nanosheet arrays are fabricated on the surface of commercial Cu foils, which in situ generate ultrathin Cu nanosheet arrays to reduce local current density and Li2 S layers on the surfaces to work as an excellent artificial SEI. It is found that Li presents a 3D-to-planar deposition model, and Li2 S layers are reversibly movable between the 3D nanosheet surface and 2D planar surface of Li during long-term cycling. This enables ultrasmooth and dense Li deposition at 1 mA cm-2 , presenting an average thickness of ≈53.0 µm at 10 mAh cm-2 , which is close to the theoretical Li foil thickness and is highly reversible at different cycles. Thus, 1150 stable cycles with high Coulombic efficiency (CE, 99.1%) at ether-based electrolytes and 300 stable cycles with high CE (98.8%) at carbonate electrolytes are realized in half-cell with a capacity of 1 mAh cm-2 at 1 mA cm-2 . When coupled with commercial cathodes (LiFePO4 or LiNi0.8 Co0.1 Mn0.1 O2 ), the full cells present substantially enhanced cyclability under high cathode loading, limited (or zero) Li excess, and lean electrolyte conditions, even at -20 °C.

Immune-related keratitis is a rare complication associated with nivolumab treatment in a patient with advanced colorectal cancer: A case report.

Background: Immunotherapy has been widely used to treat Colorectal cancer but has also observe some immune-related adverse effects. With proper treatment, most irAE can be solved and the effect of immunotherapy will not be affected by temporary immunosuppression. However, there are few reports about corneal irAE, and the current understanding of irAE is incomplete. Here we report a metastatic colorectal cancer case of immune-related keratitis caused by nivolumab and to explore the occurrence of immune-related keratitis. Case description: Here we report the case of a 49-year-old man with mCRC who had no previous ocular disease but developed immune-related ulcerative keratitis after treatment with nivolumab. We summarize a large amount of literature to discuss the mechanism of immune-related keratitis. In addition, we conclude a method that may be used to detect the occurrence of immune keratitis, by monitoring MMPs and maspin in patients treated with nivolumab. We believe immune-related keratitis may be a rare complication of nivolumab in the treatment of mCRC. The effect of simple anti-infective therapy and repair-promoting drugs was not obvious, but the effect of glucocorticoid combined with autologous serum was significant. Conclusion: The mechanism of immune-related keratitis is that nivolumab destroys the immune microenvironment and ACAID, and affects corneal healing. Patients who use nivolumab can prevent immune keratitis by testing MMPs and maspin. The occurrence of immune keratitis may be a good indicator of the efficacy of ICI, and further study can be done in the follow-up.

Single atom catalysts in Van der Waals gaps.

Single-atom catalysts provide efficiently utilized active sites to improve catalytic activities while improving the stability and enhancing the activities to the level of their bulk metallic counterparts are grand challenges. Herein, we demonstrate a family of single-atom catalysts with different interaction types by confining metal single atoms into the van der Waals gap of two-dimensional SnS2. The relatively weak bonding between the noble metal single atoms and the host endows the single atoms with more intrinsic catalytic activity compared to the ones with strong chemical bonding, while the protection offered by the layered material leads to ultrahigh stability compared to the physically adsorbed single-atom catalysts on the surface. Specifically, the trace Pt-intercalated SnS2 catalyst has superior long-term durability and comparable performance to that of commercial 10 wt% Pt/C catalyst in hydrogen evolution reaction. This work opens an avenue to explore high-performance intercalated single-atom electrocatalysts within various two-dimensional materials.

Three-Dimensional Fe Single-Atom Catalyst for High-Performance Cathode of Zn-Air Batteries.

Designing cost-effective and highly active oxygen reduction reaction (ORR) catalysts is critical for the development of Zn-air batteries (ZABs). Iron-nitrogen-carbon (Fe-N-C) catalysts with single-atom Fe-Nx active sites are considered as one of the most promising alternatives to noble Pt but are hindered by unsatisfactory activity and durability. Herein, a NaCl template-assisted in situ pyrolysis technique is utilized to massively fabricate Fe-N-C single-atom catalysts (SACs) anchored on the three-dimensional open-pore carbon networks (denoted as 3D SAFe). The 3D SAFe catalyst exhibits ultrahigh activity with a half-wave potential of 0.90 V (vs RHE), benefiting from the enhanced mass diffusion and the increased amount of effective Fe-N4 sites. Consequently, the ZABs assembled with 3D SAFe deliver high peak power density up to 156 mW cm-2 and outstanding durability of 80 h, suggesting the application potential of the 3D SAFe catalyst. This work inspires the rational design and synthesis of highly efficient SACs for ZABs.

Electrochemical CO2 reduction to ethylene by ultrathin CuO nanoplate arrays.

Electrochemical reduction of CO2 to multi-carbon fuels and chemical feedstocks is an appealing approach to mitigate excessive CO2 emissions. However, the reported catalysts always show either a low Faradaic efficiency of the C2+ product or poor long-term stability. Herein, we report a facile and scalable anodic corrosion method to synthesize oxygen-rich ultrathin CuO nanoplate arrays, which form Cu/Cu2O heterogeneous interfaces through self-evolution during electrocatalysis. The catalyst exhibits a high C2H4 Faradaic efficiency of 84.5%, stable electrolysis for ~55 h in a flow cell using a neutral KCl electrolyte, and a full-cell ethylene energy efficiency of 27.6% at 200 mA cm-2 in a membrane electrode assembly electrolyzer. Mechanism analyses reveal that the stable nanostructures, stable Cu/Cu2O interfaces, and enhanced adsorption of the *OCCOH intermediate preserve selective and prolonged C2H4 production. The robust and scalable produced catalyst coupled with mild electrolytic conditions facilitates the practical application of electrochemical CO2 reduction.

Constructing Artificial SEI Layer on Lithiophilic MXene Surface for High-Performance Lithium Metal Anodes.

MXene has been found as a good host for lithium (Li) metal anodes because of its high specific surface area, lithiophilicity, good stability with lithium, and the in situ formed LiF protective layer. However, the formation of Li dendrites and dead Li is inevitable during long-term cycle due to the lack of protection at the Li/electrolyte interface. Herein, a stable artificial solid electrolyte interface (SEI) is constructed on the MXene surface by using insulating g-C3 N4 layer to regulate homogeneous Li plating/stripping. The 2D/2D MXene/g-C3 N4 composite nanosheets can not only guarantee sufficient lithiophilic sites, but also protect the Li metal from continuous corrosion by electrolytes. Thus, the Ti3 C2 Tx /g-C3 N4 electrode enables conformal Li deposition, enhanced average Coulombic efficiency (CE) of 98.4%, and longer cycle lifespan over 400 cycles with an areal capacity of 1.0 mAh cm-2 at 0.5 mA cm-2 . Full cells paired with LiFePO4 (LFP) cathode also achieve enhanced rate capacity and cycling stability with higher capacity retention of 85.5% after 320 cycles at 0.5C. The advantages of the 2D/2D lithiophilic layer/artificial SEI layer heterostructures provide important insights into the design strategies for high-performance and stable Li metal batteries.