460 research outputs found

    Cross-relation Cross-bag Attention for Distantly-supervised Relation Extraction

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    Distant supervision leverages knowledge bases to automatically label instances, thus allowing us to train relation extractor without human annotations. However, the generated training data typically contain massive noise, and may result in poor performances with the vanilla supervised learning. In this paper, we propose to conduct multi-instance learning with a novel Cross-relation Cross-bag Selective Attention (C2^2SA), which leads to noise-robust training for distant supervised relation extractor. Specifically, we employ the sentence-level selective attention to reduce the effect of noisy or mismatched sentences, while the correlation among relations were captured to improve the quality of attention weights. Moreover, instead of treating all entity-pairs equally, we try to pay more attention to entity-pairs with a higher quality. Similarly, we adopt the selective attention mechanism to achieve this goal. Experiments with two types of relation extractor demonstrate the superiority of the proposed approach over the state-of-the-art, while further ablation studies verify our intuitions and demonstrate the effectiveness of our proposed two techniques.Comment: AAAI 201

    Observation of a thermoelectric Hall plateau in the extreme quantum limit

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    The thermoelectric Hall effect is the generation of a transverse heat current upon applying an electric field in the presence of a magnetic field. Here we demonstrate that the thermoelectric Hall conductivity αxy\alpha_{xy} in the three-dimensional Dirac semimetal ZrTe5_5 acquires a robust plateau in the extreme quantum limit of magnetic field. The plateau value is independent of the field strength, disorder strength, carrier concentration, or carrier sign. We explain this plateau theoretically and show that it is a unique signature of three-dimensional Dirac or Weyl electrons in the extreme quantum limit. We further find that other thermoelectric coefficients, such as the thermopower and Nernst coefficient, are greatly enhanced over their zero-field values even at relatively low fields.Comment: 17+21 pages, 3+14 figures; published versio

    Methylation Profile of Single Hepatocytes Derived from Hepatitis B Virus-Related Hepatocellular Carcinoma

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    BACKGROUND: With the development of high-throughput screening, a variety of genetic alterations has been found in hepatocellular carcinoma (HCC). Although previous studies on HCC methylation profiles have focused on liver tissue, studies using isolated hepatocytes are rare. The heterogeneity of liver composition may impact the genuine methylation status of HCC; therefore, it is important to clarify the methylation profile of hepatocytes to aid in understanding the process of tumorigenesis. METHODS AND FINDINGS: The global methylation profile of single hepatocytes isolated from liver tissue of hepatitis B virus (HBV) related HCC (HBHC) was analyzed using Illumina Infinium Human Methylation27 BeadChips, and combined bisulfite restriction analysis (COBRA) and bisulfite sequencing were used to validate the 20 significant hypermethylated genes identified. In this study, we found many noteworthy differences in the genome-wide methylation profiles of single hepatocytes of HBHC. Unsupervised hierarchical clustering analysis showed that hepatocyte methylation profiles could be classified according to three cell types: hepatocytes of HCC, adjacent hepatocytes and normal hepatocytes. Among the 20 most hypermethylated genes in the hepatocytes of HBHC, 7 novel genes (WNK2, EMILIN2, TLX3, TM6SF1, TRIM58, HIST1H4Fand GRASP) were found to be hypermethylated in HBHC and hypomethylated in paired adjacent liver tissues; these findings have not been reported in previous studies on tissue samples. CONCLUSION: The genome-wide methylation profile of purified single hepatocytes of HBHC was aided in understanding the process of tumorigenesis, and a series of novel methylated genes found in this study have the potential to be biomarkers for the diagnosis and prognosis of HBHC

    Correlation between tongue manifestations and glucose, total cholesterol, and high-density lipoprotein cholesterol in patients with acute cerebral infarction

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    AbstractObjectiveTo analyze the association between tongue manifestations and the levels of glucose (GLU), total cholesterol (TCH), and high-density lipoprotein cholesterol (HDL-C) in subjects with acute cerebral infarction.MethodsHospitalized patients with first unilateral cerebral infarction in the Neurological Department of Xuanwu Hospital were included and the correlation between tongue fur color, fur nature, and the levels of GLU, TCH, HDL-C were analyzed.ResultsHDL level in the thin fur group was higher than that in the thick fur group (P=0.02). The difference in the levels of GLU, TCH, and HDL-C among the groups was significant (P<0.05), classified in terms of slippery, moist, and dry fur. Further comparison between the groups by Student-Newman-Keuls test showed that GLU level in the dry fur group was the highest. Moreover, the TCH level in the slippery fur group was higher than the other two groups.ConclusionA correlation between tongue manifestations and GLU, TCH, HDL-C was identified in the patients with acute cerebral infarction

    What inflation measure should a currency union target?

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    What is the appropriate inflation target for a currency union, when conducting monetary policy: core inflation or headline inflation? We answer the question in a two-country New Keynesian model with an energy sector. We derive the welfare loss function and find that optimal monetary policy should target output gaps, the terms of trade gap, the Prouder Price Index inflation rates, and the real marginal cost gaps. We use the welfare loss function to evaluate two alternative Taylor-type monetary policy rules. We find that the choice of preferred policy rule depends on the shocks. Specifically, when productivity shocks hit the economy, the policymaker should follow the headline inflation Taylor rule, while the core inflation Taylor rule should be followed when a negative energy endowment shock hits the economy

    What inflation measure should a currency union target?

    Get PDF
    What is the appropriate inflation target for a currency union, when conducting monetary policy: core inflation or headline inflation? We answer the question in a two-country New Keynesian model with an energy sector. We derive the welfare loss function and find that optimal monetary policy should target output gaps, the terms of trade gap, the Prouder Price Index inflation rates, and the real marginal cost gaps. We use the welfare loss function to evaluate two alternative Taylor-type monetary policy rules. We find that the choice of preferred policy rule depends on the shocks. Specifically, when productivity shocks hit the economy, the policymaker should follow the headline inflation Taylor rule, while the core inflation Taylor rule should be followed when a negative energy endowment shock hits the economy
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