528 research outputs found

    Evolution of a bosonic mode across the superconducting dome in the high-Tc cuprate Pr(2-x)Ce(x)CuO(4-{\delta})

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    We report a detailed spectroscopic study of the electron doped cuprate superconductor Pr(2-x)Ce(x)CuO(4-{\delta}) using point contact junctions for x=0.125(underdoped), x=0.15(optimally doped) and x=0.17(overdoped). From our conductance measurements we are able to identify bosonic resonances for each doping. These excitations disappear above the critical temperature, and above the critical magnetic field. We find that the energy of the bosonic excitations decreases with doping, which excludes lattice vibrations as the paring glue. We conclude that the bosonic mediator for these cuprates is more likely to be spin excitations.Comment: 4 page

    Coexistence of a triplet nodal order-parameter and a singlet order-parameter at the interfaces of ferromagnet-superconductor Co/CoO/In junctions

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    We present differential conductance measurements of Cobalt / Cobalt-Oxide / Indium planar junctions, 500nm x 500nm in size. The junctions span a wide range of barriers, from very low to a tunnel barrier. The characteristic conductance of all the junctions show a V-shape structure at low bias instead of the U-shape characteristic of a s-wave order parameter. The bias of the conductance peaks is, for all junctions, larger than the gap of indium. Both properties exclude pure s-wave pairing. The data is well fitted by a model that assumes the coexistence of s-wave singlet and equal spin p-wave triplet fluids. We find that the values of the s-wave and p-wave gaps follow the BCS temperature dependance and that the amplitude of the s-wave fluid increases with the barrier strength.Comment: 5 pages, Accepted to Phys. Rev.

    “And All of That”: The Long List in Political Discourse

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    We look at long lists (i.e., longer than three parts) in political discourse, especially in talk shows from three cultures, the U.S., Pakistan, and the Netherlands, and ask how a long list is accomplished. Long lists are routinely produced in political discourse by extending the typical three-part list. The listing process to create a long list can happen in many ways, explicitly via counting verbally or physically and implicitly through other resources. These resources can also be used to project a list in advance and to create one retrospectively. Last, listing in politics creates two problems for the lister, requiring an artful application of the available listing resources. The audience may orient to only three parts, and the politician is faced with selecting the last item. Thus, we show that politicians use lists to structure their talk, but they also have to anticipate problems regarding the practice of listing

    Field Induced Nodal Order Parameter in the Tunneling Spectrum of YBa2_2Cu3_3O7x_{7-x} Superconductor

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    We report planar tunneling measurements on thin films of YBa2_2Cu3_3O7x_{7-x} at various doping levels under magnetic fields. By choosing a special setup configuration, we have probed a field induced energy scale that dominates in the vicinity of a node of the d-wave superconducting order parameter. We found a high doping sensitivity for this energy scale. At Optimum doping this energy scale is in agreement with an induced idxyid_{xy} order parameter. We found that it can be followed down to low fields at optimum doping, but not away from it.Comment: 9 pages, 8 figures, accepted for publication in Phys. Rev.

    GLUT-1 deficiency presenting with seizures and reversible leukoencephalopathy on MRI imaging

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    Glucose transporter type 1 (GLUT1) deficiency syndrome is a well recognised genetic neurometabolic disorder typically presenting with progressive encephalopathy, acquired microcephaly and drug-resistant epilepsy. Imaging is normal in the majority. Here we describe a 5-month-old boy who presented with motor delay, myoclonic jerks and tonic-clonic seizures. His MRI brain scan revealed confluent symmetrical T2 hyperintense signal abnormality in both anterior frontal lobes and delayed myelination. Neurometabolic screen revealed low CSF glucose and lactate levels. A pathogenic de novo heterozygous mutation in SLC2A1 (c.275+1G > A) confirmed the diagnosis of GLUT1 deficiency. Ketogenic diet resulted in a dramatic termination of his seizures at 72 h. At 15 months, he continued to be seizure free with marked developmental catch up. Repeat imaging revealed a significant resolution of the previously seen changes. This case suggests that GLUT1 deficiency should be considered in the differential diagnosis of infants with suspected genetic leukoencephalopathies with important treatment implications

    Treatment Strategies for Central Nervous System Effects in Primary and Secondary Haemophagocytic Lymphohistiocytosis in Children

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    Purpose of Review: This review presents an appraisal of current therapeutic options for the treatment of central nervous system haemophagocytic lymphohistiocytosis (CNS-HLH) in the context of systemic disease, as well as when CNS features occur in isolation. We present the reader with a diagnostic approach to CNS-HLH and commonly used treatment protocols. We discuss and evaluate newer treatments on the horizon. Recent Findings: Mortality is high in patients who do not undergo HSCT, and while larger studies are required to establish benefit in many treatments, a number of new treatments are currently being evaluated. Alemtuzumab is being used as a first-line treatment for CNS-HLH in a phase I/II multicentre prospective clinical trial as an alternative to traditional HLH-1994 and 2004 protocols. It has also been used successfully as a second-line agent for the treatment of isolated CNS-HLH that is refractory to standard treatment. Ruxolitinib and emapalumab are new immunotherapies that block the Janus kinase—Signal Transducer and Activator of Transcription (JAK-STAT) pathway that have shown efficacy in refractory HLH, including for CNS-HLH disease. Summary: Treatment of CNS-HLH often requires HLH-94 or 2004 protocols followed by haematopoietic stem cell transplantation (HSCT) to maintain remission, although relapse can occur, particularly with reduced intensity conditioning if donor chimerism falls. CNS features have been shown to improve or stabilise following HSCT in CNS-HLH in the context of systemic disease and in isolated CNS-HLH. Encouraging reports of early cohort studies suggest alemtuzumab and the Janus kinase (JAK) inhibitor ruxolitinib offer potential salvage therapy for relapsed and refractory CNS-HLH. Newer immunotherapies such as tocilizumab and natalizumab have been shown to be beneficial in sporadic cases. CNS-HLH due to primary gene defects may be amenable to gene therapy in the future

    Preface

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    These proceedings contain the papers of the Third International Workshop on Recent Trends in News Informa-tion Retrieval (NewsIR\u201919) held in conjunction with the ACM SIGIR 2019 conference in Paris, France, on the25thof July 2019. Ten full papers and two short papers (one position paper and one demo paper) were selectedby the programme committee from a total of 21 submissions. Each submitted paper was reviewed by at leastthree members of an international programme committee. In addition to the selected papers, the workshopfeatures one keynote and one invited talk. The Keynote speech is given by Aron Pilhofer \u201cFrom Redlining toRobots: How newsrooms apply technology to the craft of journalism\u201d. The invited talk is given by FriedrichLindenberg \u201cMining Leaks and Open Data to Follow the Money\u201d. We would like to thank SIGIR for hostingus. Thanks also go to the keynote speakers, the program committee, the paper authors, and the participants,for without these people there would be no worksho
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