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Background: Accurate segmentation of brain glioma is a critical prerequisite for clinical diagnosis, surgical planning and treatment evaluation. In current clinical workflow, physicians typically perform delineation of brain tumor subregions slice‐by‐slice, which is more susceptible to variabilities in raters and also time‐consuming. Besides, even though convolutional neural networks (CNNs) are driving progress, the performance of standard models still have some room for further improvement. Purpose: To deal with these issues, this paper proposes an attention‐guided multi‐scale context aggregation network (AMCA‐Net) for the accurate segmentation of brain glioma in the magnetic resonance imaging (MRI) images with multi‐modalities. Methods: AMCA‐Net extracts the multi‐scale features from the MRI images and fuses the extracted discriminative features via a self‐attention mechanism for brain glioma segmentation. The extraction is performed via a series of down‐sampling, convolution layers, and the global context information guidance (GCIG) modules are developed to fuse the features extracted for contextual features. At the end of the down‐sampling, a multi‐scale fusion (MSF) module is designed to exploit and combine all the extracted multi‐scale features. Each of the GCIG and MSF modules contain a channel attention (CA) module that can adaptively calibrate feature responses and emphasize the most relevant features. Finally, multiple predictions with different resolutions are fused through different weightings given by a multi‐resolution adaptation (MRA) module instead of the use of averaging or max‐pooling to improve the final segmentation results. Results: Datasets used in this paper are publicly accessible, that is, the Multimodal Brain Tumor Segmentation Challenges 2018 (BraTS2018) and 2019 (BraTS2019). BraTS2018 contains 285 patient cases and BraTS2019 contains 335 cases. Simulations show that the AMCA‐Net has better or comparable performance against that of the other state‐of‐the‐art models. In terms of the Dice score and Hausdorff 95 for the BraTS2018 dataset, 90.4% and 10.2 mm for the whole tumor region (WT), 83.9% and 7.4 mm for the tumor core region (TC), 80.2% and 4.3 mm for the enhancing tumor region (ET), whereas the Dice score and Hausdorff 95 for the BraTS2019 dataset, 91.0% and 10.7 mm for the WT, 84.2% and 8.4 mm for the TC, 80.1% and 4.8 mm for the ET. Conclusions: The proposed AMCA‐Net performs comparably well in comparison to several state‐of‐the‐art neural net models in identifying the areas involving the peritumoral edema, enhancing tumor, and necrotic and non‐enhancing tumor core of brain glioma, which has great potential for clinical practice. In future research, we will further explore the feasibility of applying AMCA‐Net to other similar segmentation tasks. [ABSTRACT FROM AUTHOR]

Sonodynamic therapy (SDT) typically suffers from compromised anticancer efficacy owing to the low reactive oxygen species (ROS) yield and complicated tumor microenvironment (TME) which can consume ROS and support the occurrence and development of tumors. Herein, ultrathin‐FeOOH‐coated MnO2 nanospheres (denoted as MO@FHO) as sonosensitizers which can not only facilitate ultrasound (US)‐triggered ROS but also tune the TME by hypoxia alleviation, H2O2 consumption as well as glutathione (GSH) depletion are designed. The FeOOH coating will boost the production yield of singlet oxygen (1O2) and hydroxyl radicals (•OH) by inhibiting the recombination of US‐initiated electron–hole pairs and Fenton‐like reaction, respectively. Additionally, the catalase‐like and GSH peroxidase‐like activities of MO@FHO nanospheres enable them to break the TME equilibrium via hypoxia alleviation and GSH depletion. The combination of high ROS yield and fundamental destruction of TME equilibrium results in satisfactory antitumor outcomes, as demonstrated by the high tumor suppression efficacy of MO@FHO on MDA‐MB‐231‐tumor‐bearing mice. No obvious toxicity is detected to normal tissues at therapeutic doses in vivo. The capability to modulate the ROS production and TME simultaneously can afford new probability for the development of advanced sonosensitizers for synergistic comprehensive cancer therapy. [ABSTRACT FROM AUTHOR]

Intraoperative diagnosis of metastatic tumors is of significant importance to the treatment of ovarian cancer. NIR‐II fluorescence imaging holds great promise for facile detection of tumor in situ with high sensitivity and resolution. Herein, a kind of NIR‐II fluorescent polymer dots (NIR‐II Pdots) with high brightness is developed for real‐time detection of metastatic ovarian cancer via NIR‐II fluorescence imaging. The NIR‐II Pdots are constructed via the self‐assembly of NIR‐II emissive aggregation induced emission luminogens (NIR‐II AIEgens) and poly (styrene)‐graft‐poly(ethylene glycol) in water. Such NIR‐II Pdots show very high fluorophore contents of nearly 30% and high quantum yield of 5.4% at emission maximum near 1020 nm. Further modification of the NIR‐II Pdots with targeting peptides yields NIR‐II Pdots‐GnRH, which can afford enhanced affinity of NIR‐II Pdots to ovarian cancer. Upon intravenous injection of the NIR‐II Pdots, whole‐body organs and vessels, peritoneal and lymphatic metastases of ovarian cancer are clearly visualized by NIR‐II fluorescence imaging. Under the guidance of NIR‐II fluorescence imaging, the metastatic foci with the diameter down to ≈2 mm can be facilely eliminated. The results indicate preclinical potential value of the NIR‐II Pdots for metastatic ovarian cancer detection. [ABSTRACT FROM AUTHOR]

Among various charge‐carrier ions for aqueous batteries, non‐metal hydronium (H3O+) with small ionic size and fast diffusion kinetics empowers H3O+‐intercalation electrodes with high rate performance and fast‐charging capability. However, pure H3O+ charge carriers for inorganic electrode materials have only been observed in corrosive acidic electrolytes, rather than in mild neutral electrolytes. Herein, we report how selective H3O+ intercalation in a neutral ZnCl2 electrolyte can be achieved for water‐proton co‐intercalated α‐MoO3 (denoted WP‐MoO3). H2O molecules located between MoO3 interlayers block Zn2+ intercalation pathways while allowing smooth H3O+ intercalation/diffusion through a Grotthuss proton‐conduction mechanism. Compared to α‐MoO3 with a Zn2+‐intercalation mechanism, WP‐MoO3 delivers the substantially enhanced specific capacity (356.8 vs. 184.0 mA h g−1), rate capability (77.5 % vs. 42.2 % from 0.4 to 4.8 A g−1), and cycling stability (83 % vs. 13 % over 1000 cycles). This work demonstrates the possibility of modulating electrochemical intercalating ions by interlayer engineering, to construct high‐rate and long‐life electrodes for aqueous batteries. [ABSTRACT FROM AUTHOR]

Zinc‐ion hybrid supercapacitors (ZHSCs) have garnered increasing attention as promising energy storage devices in recent years, as they combine the advantages of high‐energy Zn‐ion batteries and high‐power supercapacitors. However, the development of ZHSCs is still in its infancy and there are many bottlenecks to overcome. In particular, the challenge induced by the limited ion adsorption capability of carbon‐positive electrodes severely restricts the energy density of ZHSCs. Therefore, it has become a key issue to design novel carbon‐positive electrodes that enable high energy density yet do not deteriorate the intrinsic power capability and long‐term durability. This study focuses on recent achievements in synthesis, morphology, and electrochemical performance of various carbon materials applied in ZHSCs. The modification strategies to optimize their electrochemical performance are briefly summarized. In addition, current challenges and future opportunities in this field are also outlined. This review will be beneficial to provide an organized framework for the research systems of carbon‐positive electrodes and develop novel ZHSCs with high energy density. [ABSTRACT FROM AUTHOR]

Metal oxides hold great promise as robust sonosensitizers for sonodynamic therapy (SDT). However, they usually suffer from limited production yield of reactive oxygen species (ROS) due to the fast recombination of ultrasound‐triggered electrons and holes. Herein, porous lanthanum (La)‐doped MnO2 (LMO) nanoparticles are firstly developed as promising sonosensitizers in SDT. The strategic introduction of La dopants greatly promotes the separation efficiency of ultrasound‐triggered electrons and holes of MnO2, endowing them with significantly improved ROS yield. Consequently, the LMO with polyethylene glycol decoration exhibits good SDT activity toward breast cancer cells. This work highlights the doping strategy for the development of enhanced ROS production of metal oxide sonosensitizers for SDT. [ABSTRACT FROM AUTHOR]

Hydrated vanadium pentoxide (VO) cathodes with two‐dimensional bilayer structures hold great potential for advanced aqueous Zn‐ion batteries (ZIBs) construction, but their further application is impeded by the poor cycling stability. Herein, to address this issue and enhance the Zn ion storage capability, La3+ with a big radius was selected to finely tune their nanostructure. The strategic introduction of La3+ to VO led to the formation of LaVO4, which showed larger interplanar spacing, better electrical conductivity, and superior Zn‐ion diffusion efficiency. These unique characteristics were beneficial in the (de)intercalation and the prevention of electrode degradation/collapse, thereby significantly strengthening the corresponding electrochemical performance. As a consequence, the cathode possessed a high specific capacity of 472.5 mAh g−1 at a current density of 0.38 A g−1 and displayed good rate performance, accompanied by enduring cycling stability (no decay after 2000 cycles). Besides, when equipped as an aqueous ZIB, it delivered an outstanding peak energy density of 341.9 Wh kg−1 and a peak power density of 3.22 kW kg−1, surpassing most VO‐based energy‐storage devices. [ABSTRACT FROM AUTHOR]