673 research outputs found

    Fully Conjugated Phthalocyanine Copper Metal-Organic Frameworks for Sodium-Iodine Batteries with Long-Time-Cycling Durability

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    Rechargeable sodium-iodine (Na-I-2) batteries are attracting growing attention for grid-scale energy storage due to their abundant resources, low cost, environmental friendliness, high theoretical capacity (211 mAh g(-1)), and excellent electrochemical reversibility. Nevertheless, the practical application of Na-I-2 batteries is severely hindered by their poor cycle stability owing to the serious dissolution of polyiodide in the electrolyte during charge/discharge processes. Herein, the atomic modulation of metal-bis(dihydroxy) species in a fully conjugated phthalocyanine copper metal-organic framework (MOF) for suppression of polyiodide dissolution toward long-time cycling Na-I-2 batteries is demonstrated. The Fe-2[(2,3,9,10,16,17,23,24-octahydroxy phthalocyaninato)Cu] MOF composited with I-2 (Fe-2-O-8-PcCu/I-2) serves as a cathode for a Na-I-2 battery exhibiting a stable specific capacity of 150 mAh g(-1) after 3200 cycles and outperforming the state-of-the-art cathodes for Na-I-2 batteries. Operando spectroelectrochemical and electrochemical kinetics analyses together with density functional theory calculations reveal that the square planar iron-bis(dihydroxy) (Fe-O-4) species in Fe-2-O-8-PcCu are responsible for the binding of polyiodide to restrain its dissolution into electrolyte. Besides the monovalent Na-I-2 batteries in organic electrolytes, the Fe-2-O-8-PcCu/I-2 cathode also operates stably in other metal-I-2 batteries like aqueous multivalent Zn-I-2 batteries. Thus, this work offers a new strategy for designing stable cathode materials toward high-performance metal-iodine batteries

    Self-Attention Empowered Graph Convolutional Network for Structure Learning and Node Embedding

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    In representation learning on graph-structured data, many popular graph neural networks (GNNs) fail to capture long-range dependencies, leading to performance degradation. Furthermore, this weakness is magnified when the concerned graph is characterized by heterophily (low homophily). To solve this issue, this paper proposes a novel graph learning framework called the graph convolutional network with self-attention (GCN-SA). The proposed scheme exhibits an exceptional generalization capability in node-level representation learning. The proposed GCN-SA contains two enhancements corresponding to edges and node features. For edges, we utilize a self-attention mechanism to design a stable and effective graph-structure-learning module that can capture the internal correlation between any pair of nodes. This graph-structure-learning module can identify reliable neighbors for each node from the entire graph. Regarding the node features, we modify the transformer block to make it more applicable to enable GCN to fuse valuable information from the entire graph. These two enhancements work in distinct ways to help our GCN-SA capture long-range dependencies, enabling it to perform representation learning on graphs with varying levels of homophily. The experimental results on benchmark datasets demonstrate the effectiveness of the proposed GCN-SA. Compared to other outstanding GNN counterparts, the proposed GCN-SA is competitive.Comment: 33 pages,6 figures,9 table

    swSpTRSV: A Fast Sparse Triangular Solve with Sparse Level Tile Layout on Sunway Architectures

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    Sparse triangular solve (SpTRSV) is one of the most important kernels in many real-world applications. Currently, much research on parallel SpTRSV focuses on level-set construction for reducing the number of inter-level synchronizations. However, the out-of-control data reuse and high cost for global memory or shared cache access in inter-level synchronization have been largely neglected in existing work. In this paper, we propose a novel data layout called Sparse Level Tile to make all data reuse under control, and design a Producer-Consumer pairing method to make any inter-level synchronization only happen in very fast register communication. We implement our data layout and algorithms on an SW26010 many-core processor, which is the main building-block of the current world fastest supercomputer Sunway Taihulight. The experimental results of testing all 2057 square matrices from the Florida Matrix Collection show that our method achieves an average speedup of 6.9 and the best speedup of 38.5 over parallel level-set method. Our method also outperforms the latest methods on a KNC many-core processor in 1856 matrices and the latest methods on a K80 GPU in 1672 matrices, respectively.publishedVersion© 2018 Copyright held by the owner/author(s). Publication rights licensed to the Association for Computing Machinery

    In vivo antidiabetic activity of qwueous extract of Artemisia argyi (Chinese mugwort) in alloxan-induced diabetic rats

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    Purpose: To determine the antidiabetic, antioxidant and anti-hyperlipidemic effects of aqueous leaf extract of Artemisia argyi (Asteraceae) in alloxan (ALX)-induced diabetic rats. Experimental: Soxhlet apparatus was packed with grinded leaves of A. Argyi and subjected to extraction by double distillation using water as  running solvent for 4 – 5 h. Male albino Wistar rats weighing 150 ± 10 g were used in this study. Diabetes was induced in overnight-fasted rats via intraperitoneal administration of freshly prepared 10 % alloxan solution at a dose of 186.9 mg/kg. Serum glucose (Glc), high-density lipoprotein cholesterol (HDL-c), triglycerides (TGs) and total cholesterol (TC) were evaluated using Randox assay kits. Serum reduced glutathione (GSH) was assayed using a slight modification of a previously reproted procedure, while histological examination was carried out microscopically after hematoxylin and eosin staining. Results: Oral administration of aqueous extract of Artemisia argyi significantly reduced ALX-induced increases in glycosylated hemoglobin and blood glucose, but significantly increased total protein, hemoglobin, insulin, and C-peptide levels (p < 0.05). Administration of the extract also led to a significant upsurge in non-enzymic antioxidants i.e. ceruloplasmin, GSH, vitamin E and vitamin C. The extract produced a hypolipidemic effect by significantly reducing total cholesterol (TC) and serum TGs. The hypoglycemic and hypolipidemic effects of the extract were dose-dependent (p < 0.05). Histological examination of the pancreas revealed that the extract protected the integrity of beta cells in ALXinduced diabetic rats. Conclusion: These results indicate the beneficial effects of Artemisia argyi against diabetes mellitus. Thus, Artemisia argyi may be useful in the management of diabetes mellitus. Keywords: Artemisia argyi, Antidiabetic, Glutathione, Histopathology, Antioxidan

    Late Fusion with Triplet Margin Objective for Multimodal Ideology Prediction and Analysis

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    Prior work on ideology prediction has largely focused on single modalities, i.e., text or images. In this work, we introduce the task of multimodal ideology prediction, where a model predicts binary or five-point scale ideological leanings, given a text-image pair with political content. We first collect five new large-scale datasets with English documents and images along with their ideological leanings, covering news articles from a wide range of US mainstream media and social media posts from Reddit and Twitter. We conduct in-depth analyses of news articles and reveal differences in image content and usage across the political spectrum. Furthermore, we perform extensive experiments and ablation studies, demonstrating the effectiveness of targeted pretraining objectives on different model components. Our best-performing model, a late-fusion architecture pretrained with a triplet objective over multimodal content, outperforms the state-of-the-art text-only model by almost 4% and a strong multimodal baseline with no pretraining by over 3%.Comment: EMNLP 202

    MOKA: Moral Knowledge Augmentation for Moral Event Extraction

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    News media often strive to minimize explicit moral language in news articles, yet most articles are dense with moral values as expressed through the reported events themselves. However, values that are reflected in the intricate dynamics among participating entities and moral events are far more challenging for most NLP systems to detect, including LLMs. To study this phenomenon, we annotate a new dataset, MORAL EVENTS, consisting of 5,494 structured event annotations on 474 news articles by diverse US media across the political spectrum. We further propose MOKA, a moral event extraction framework with MOral Knowledge Augmentation, which leverages knowledge derived from moral words and moral scenarios to produce structural representations of morality-bearing events. Experiments show that MOKA outperforms competitive baselines across three moral event understanding tasks. Further analysis shows even ostensibly nonpartisan media engage in the selective reporting of moral events. Our data and codebase are available at https://github.com/launchnlp/MOKA.Comment: NAACL'24 Main Conferenc

    Crossing the Aisle: Unveiling Partisan and Counter-Partisan Events in News Reporting

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    News media is expected to uphold unbiased reporting. Yet they may still affect public opinion by selectively including or omitting events that support or contradict their ideological positions. Prior work in NLP has only studied media bias via linguistic style and word usage. In this paper, we study to which degree media balances news reporting and affects consumers through event inclusion or omission. We first introduce the task of detecting both partisan and counter-partisan events: events that support or oppose the author's political ideology. To conduct our study, we annotate a high-quality dataset, PAC, containing 8,511 (counter-)partisan event annotations in 304 news articles from ideologically diverse media outlets. We benchmark PAC to highlight the challenges of this task. Our findings highlight both the ways in which the news subtly shapes opinion and the need for large language models that better understand events within a broader context. Our dataset can be found at https://github.com/launchnlp/Partisan-Event-Dataset.Comment: EMNLP'23 Finding
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