49 research outputs found

    Big Data Small Data, In Domain Out-of Domain, Known Word Unknown Word: The Impact of Word Representations on Sequence Labelling Tasks

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    Word embeddings -- distributed word representations that can be learned from unlabelled data -- have been shown to have high utility in many natural language processing applications. In this paper, we perform an extrinsic evaluation of five popular word embedding methods in the context of four sequence labelling tasks: POS-tagging, syntactic chunking, NER and MWE identification. A particular focus of the paper is analysing the effects of task-based updating of word representations. We show that when using word embeddings as features, as few as several hundred training instances are sufficient to achieve competitive results, and that word embeddings lead to improvements over OOV words and out of domain. Perhaps more surprisingly, our results indicate there is little difference between the different word embedding methods, and that simple Brown clusters are often competitive with word embeddings across all tasks we consider

    Big Data Small Data, In Domain Out-of Domain, Known Word Unknown Word: The Impact of Word Representations on Sequence Labelling Tasks

    Get PDF
    Word embeddings — distributed word representations that can be learned from unlabelled data — have been shown to have high utility in many natural language processing applications. In this paper, we perform an extrinsic evaluation of four popular word embedding methods in the context of four sequence labelling tasks:part-of-speech tagging, syntactic chunking, named entity recognition, and multiword expression identification. A particular focus of the paper is analysing the effects of task-based updating of word representations. We show that when using word embeddings as features, as few as several hundred training instances are sufficient to achieve competitive results, and that word embeddings lead to improvements over out-of-vocabulary words and also out of domain. Perhaps more surprisingly, our results indicate there is little difference between the different word embedding methods, and that simple Brown clusters are often competitive with word embeddings across all tasks we conside

    High-Dose Dexamethasone Alters the Increase in Interleukin-16 Level in Adult Immune Thrombocytopenia

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    Adult primary immune thrombocytopenia (ITP) is an autoimmune-mediated haemorrhagic disorder. Interleukin-16 (IL-16) can directly affect cellular or humoural immunity by mediating the cellular cross-talk among T cells, B cells and dendritic cells. Several studies have focused on IL-16 as an immunomodulatory cytokine that takes part in Th1 polarization in autoimmune diseases. In this study, we investigated IL-16 expression in the bone marrow supernatant and plasma of ITP patients and healthy controls. What's more, we detected IL-16 expression in ITP patients with the single-agent 4-day high-dose dexamethasone (HD-DXM) therapy. In patients with active ITP, bone marrow supernatant and plasma IL-16 levels increased (P < 0.05) compared with those of healthy controls. In the meantime, the mRNA expression in BMMCs (pro-IL-16, caspase-3) and PBMCs (pro-IL-16, caspase-3 and T-bet) of ITP patients was increased (P < 0.05) relative to those of healthy controls. In patients who responded to HD-DXM therapy, both plasma IL-16 levels and gene expression in PBMCs (pro-IL-16, caspase-3, and T-bet) were decreased (P < 0.05). In summary, the abnormal level of IL-16 plays important roles in the pathogenesis of ITP. Regulating Th1 polarization associated with IL-16 by HD-DXM therapy may provide a novel insight for immune modulation in ITP

    Synthesis of Five-fold-twinned silver microwhiskers by physical vapor deposition

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    Pentagonal noble metal crystals, with a five-fold-twinned (FFT) structure that exhibits prominent noncrystallographic symmetry, have been the focus of research in the past several decades due to their promising applications in various fields such as chemical and biological sensors, electronics and optoelectronics. A great deal of previous experimental studies and theoretical analyses suggested that such an FFT structure could only exist in the nanoscale crystals, because of the lateral restriction in growth, or in microscale crystals with re-entrant grooves that can effectively release the internal strain. In this study, we synthesized the microscale single-crystalline and multi-twinned Ag crystals with various morphologies, using physical vapor deposition (PVD). FFT Ag microwhiskers with diameters up to 10 μm were produced, but without re-entrant grooves on their side surfaces. Our findings suggest that FFT whiskers can be formed without the use of any surface-capping agents or without necessitating restriction in lateral growth. This further suggests that the current understanding of the surface passivation or the strain-restriction formation of five-fold-twined micro- and nanowhiskers needs improvement

    High resolution optical images

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    Fig.1 (a) The optical image of a NW, sliding on the Si substrate at a constant speed due to the push from a W tip. (b) Mechanical loading model for the sliding NW.Fig.2 The optical images of a NW (a) rest on the Si substrate, (b) being pushed horizontally and bent, (c) being pushed and pressed, and (d) being pulled and pressed by the W tip 1; (e) being pushed and pressed and (f) being pulled and pressed by the W tip 2. The insets in (b)–(e) show the contact configuration between the W tip and the NW, where the arrows describe the direction of the force, F, acted on the NW from the W tip.Fig.3 The bent NW slid on the (a) Si substrate pushed by tip 1, (b) Si substrate pushed by tip 2, and (c) SiN substrate by tip 2. (d) Frictional shear stresses on Si and SiN substrates plotted as a function of the NW length. (e) Roughness of the Si and SiN substrates measured by AFM
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