1,571 research outputs found

    Graph Anomaly Detection with Graph Neural Networks: Current Status and Challenges

    Full text link
    Graphs are used widely to model complex systems, and detecting anomalies in a graph is an important task in the analysis of complex systems. Graph anomalies are patterns in a graph that do not conform to normal patterns expected of the attributes and/or structures of the graph. In recent years, graph neural networks (GNNs) have been studied extensively and have successfully performed difficult machine learning tasks in node classification, link prediction, and graph classification thanks to the highly expressive capability via message passing in effectively learning graph representations. To solve the graph anomaly detection problem, GNN-based methods leverage information about the graph attributes (or features) and/or structures to learn to score anomalies appropriately. In this survey, we review the recent advances made in detecting graph anomalies using GNN models. Specifically, we summarize GNN-based methods according to the graph type (i.e., static and dynamic), the anomaly type (i.e., node, edge, subgraph, and whole graph), and the network architecture (e.g., graph autoencoder, graph convolutional network). To the best of our knowledge, this survey is the first comprehensive review of graph anomaly detection methods based on GNNs.Comment: 9 pages, 2 figures, 1 tables; to appear in the IEEE Access (Please cite our journal version.

    Metal-free organic chromophores featuring an ethynyl-thienothiophene linker with an n-hexyl chain for translucent dye-sensitized solar cells

    Get PDF
    We report the simple synthesis of two organic chromophores featuring an ethynyl-thienothiophene linker with an n-hexyl chain (CSD-03 and CSD-04), their optical and electrochemical properties, and their use as photosensitizers in dye-sensitized solar cells (DSSCs). Our theoretical and experimental studies show that adding the second thienothiophene allows for narrowing the bandgap of the molecule and thus ensuring more light harvesting in the visible region. The efficiencies of both CSD-03 (5.46 ± 0.03%) and CSD-04 (5.20 ± 0.03%) are comparable to that of N719 (5.92 ± 0.01%) in translucent DSSCs fabricated with 5 μm-thick TiO2 photoanodes

    Metal-free organic chromophores featuring an ethynyl-thienothiophene linker with an n-hexyl chain for translucent dye-sensitized solar cells

    Get PDF
    We report the simple synthesis of two organic chromophores featuring an ethynyl-thienothiophene linker with an n-hexyl chain (CSD-03 and CSD-04), their optical and electrochemical properties, and their use as photosensitizers in dye-sensitized solar cells (DSSCs). Our theoretical and experimental studies show that adding the second thienothiophene allows for narrowing the bandgap of the molecule and thus ensuring more light harvesting in the visible region. The efficiencies of both CSD-03 (5.46 ± 0.03%) and CSD-04 (5.20 ± 0.03%) are comparable to that of N719 (5.92 ± 0.01%) in translucent DSSCs fabricated with 5 μm-thick TiO2 photoanodes

    Reverse Signaling of Tumor Necrosis Factor Superfamily Proteins in Macrophages and Microglia: Superfamily Portrait in the Neuroimmune Interface

    Get PDF
    The tumor necrosis factor (TNF) superfamily (TNFSF) is a protein superfamily of type II transmembrane proteins commonly containing the TNF homology domain. The superfamily contains more than 20 protein members, which can be released from the cell membrane by proteolytic cleavage. Members of the TNFSF function as cytokines and regulate diverse biological processes, including immune responses, proliferation, differentiation, apoptosis, and embryogenesis, by binding to TNFSF receptors. Many TNFSF proteins are also known to be responsible for the regulation of innate immunity and inflammation. Both receptor-mediated forward signaling and ligand-mediated reverse signaling play important roles in these processes. In this review, we discuss the functional expression and roles of various reverse signaling molecules and pathways of TNFSF members in macrophages and microglia in the central nervous system (CNS). A thorough understanding of the roles of TNFSF ligands and receptors in the activation of macrophages and microglia may improve the treatment of inflammatory diseases in the brain and periphery. In particular, TNFSF reverse signaling in microglia can be exploited to gain further insights into the functions of the neuroimmune interface in physiological and pathological processes in the CNS

    Prognostic factors for aorta remodeling after thoracic endovascular aortic repair of complicated chronic DeBakey IIIb aneurysms

    Get PDF
    ObjectivesThe use of thoracic endovascular aortic repair (TEVAR) for chronic DeBakey III type b (CDIIIb) aneurysms is controversial. We analyzed the potential prognostic factors affecting aorta remodeling after this procedure.MethodsA total of 20 patients with CDIIIb aneurysms underwent TEVAR, with full coverage of reentry tears at the descending thoracic aorta. The potential factors affecting false lumen (FL) remodeling were analyzed, including reentry tears (communicating channels visible on the computed tomography angiogram), large intimal tears below the stent graft (≥2 consecutive axial cuts on the computed tomography angiogram), visceral branches arising from the FL, and intercostal arteries (ICAs) arising from the FL.ResultsAll the patients had uneventful in-hospital courses; 2 patients (10%) required reintervention during the follow-up period. Thirteen patients (65%) had complete thrombosis of the FL at stent graft segment. Compared with the complete thrombosis group, the partial thrombosis group had more reentry tears (1.8 vs 2.3, P = .48), large intimal tears (0.8 vs 1.7, P < .05), visceral branches arising from the FL (1.2 vs 2.3, P < .05), and ICAs arising from the FL (3.8 vs 5.1, P = .35). Reentry tears, visceral branches, and ICAs from the FL were significant negative prognostic factors for FL shrinkage (P < .05).ConclusionsAlthough reentry tears above the celiac trunk were fully covered, the visceral branches and ICAs from the FL and all communicating channels below the celiac trunk kept the FL pressurized and were unfavorable prognostic factors for aorta remodeling after TEVAR for CDIIIb aneurysms

    Molecular Subgroup Analysis of Clinical Outcomes in a Phase 3 Study of Gemcitabine and Oxaliplatin with or without Erlotinib in Advanced Biliary Tract Cancer

    Get PDF
    AbstractBACKGROUND: We previously reported that the addition of erlotinib to gemcitabine and oxaliplatin (GEMOX) resulted in greater antitumor activity and might be a treatment option for patients with biliary tract cancers (BTCs). Molecular subgroup analysis of treatment outcomes in patients who had specimens available for analysis was undertaken. METHODS: Epidermal growth factor receptor (EGFR), KRAS, and PIK3CA mutations were evaluated using peptide nucleic acid–locked nucleic acid polymerase chain reaction clamp reactions. Survival and response rates (RRs) were analyzed according to the mutational status. Sixty-four patients (48.1%) were available for mutational analysis in the chemotherapy alone group and 61 (45.1%) in the chemotherapy plus erlotinib group. RESULTS: 1.6% (2/116) harbored an EGFR mutation (2 patients; exon 20), 9.6% (12/121) harbored a KRAS mutation (12 patients; exon 2), and 9.6% (12/118) harbored a PIK3CA mutation (10 patients, exon 9 and 2 patients, exon 20). The addition of erlotinib to GEMOX in patients with KRAS wild-type disease (n = 109) resulted in significant improvements in overall response compared with GEMOX alone (30.2% vs 12.5%, P = .024). In 95 patients with both wild-type KRAS and PIK3CA, there was evidence of a benefit associated with the addition of erlotinib to GEMOX with respect to RR as compared with GEMOX alone (P = .04). CONCLUSION: This study demonstrates that KRAS mutational status might be considered a predictive biomarker for the response to erlotinib in BTCs. Additionally, the mutation status of PIK3CA may be a determinant for adding erlotinib to chemotherapy in KRAS wild-type BTCs

    Could Fractional Exhaled Nitric Oxide Test be Useful in Predicting Inhaled Corticosteroid Responsiveness in Chronic Cough? A Systematic Review

    Get PDF
    © 2016 Background Fractional exhaled nitric oxide (FENO) is a safe and convenient test for assessing T H 2 airway inflammation, which is potentially useful in the management of patients with chronic cough. Objective To summarize the current evidence on the diagnostic usefulness of FENO for predicting inhaled corticosteroid (ICS) responsiveness in patients with chronic cough. Methods A systematic literature review was conducted to identify articles published in peer-reviewed journals up to February 2015, without language restriction. We included studies that reported the usefulness of FENO (index test) for predicting ICS responsiveness (reference standard) in patients with chronic cough (target condition). The data were extracted to construct a 2 × 2 accuracy table. Study quality was assessed with Quality Assessment of Diagnostic Accuracy Studies 2. Results We identified 5 original studies (2 prospective and 3 retrospective studies). We identified considerable heterogeneities in study design and outcome definitions, and thus were unable to perform a meta-analysis. The proportion of ICS responders ranged from 44% to 59%. Sensitivity and specificity ranged from 53% to 90%, and from 63% to 97%, respectively. The reported area under the curve ranged from abou t 0.60 to 0.87; however, studies with a prospective design and a lower prevalence of asthma had lower area under the curve values. None measured placebo effects or objective cough frequency. Conclusions We did not find strong evidence to support the use of FENO tests for predicting ICS responsiveness in chronic cough. Further studies need to have a randomized, placebo-controlled design, and should use validated measurement tools for cough. Standardization would facilitate the development of clinical evidence
    • …
    corecore