557 research outputs found

    Joseph Beuys: la parola e la rosa

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    Il saggio ripercorre la vita e la parabola artistica di Joseph Beyus, mettendole in relazione con le teorie antroposofiche di Rudolf Steiner, le quali ispirano diverse sue opere e, soprattutto, la presenza di due simboli in esse ricorrenti: la rosa e la croce. Pur non essendo immune da influenze esoteriche e gnostiche, Beuys prende le mosse da alcuni capisaldi dell\u2019antroposofia: l\u2019"et\ue0 del Dio-figlio\u201d, i caratteri dell\u2019Io in questa et\ue0, il mutamento della luce in calore e la nascita delle comunit\ue0 tramite la parola

    Uniform current in graphene strip with zigzag edges

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    Graphene exhibits zero-gap massless-Dirac fermion and zero density of states at E = 0. These particles form localized states called edge states on finite width strip with zigzag edges at E = 0. Naively thinking, one may expect that current is also concentrated at the edge, but Zarbo and Nikolic numerically obtained a result that the current density shows maximum at the center of the strip. We derive a rigorous relation for the current density, and clarify the reason why the current density of edge state has a maximum at the center.Comment: 5 pages, 3 figures; added references and corrected typos, to be published in J. Phys. Soc. Jpn. Vol.78 No.

    Sequence analysis of a microsatellite and its flanking regions in intraspecific hybrids of grapevine (Vitis vinifera L.)

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    Microsatellite (MS) VVMD21 (BOWERS et al. 1999) was taken as a model to explore the molecular basis of polymorphism in a panel of 6 grapevine accessions (Vitis vinifera L.), consisting of Sangiovese and Cabernet Sauvignon and 4 F1 plants derived from crossing both varieties. The 12 alleles of both parents and the progeny were cloned and sequenced. The microsatellite repeat (AG)n>6 was found in each sequence, together with a poly-T rich region that showed irregularity. Furthermore, single nucleotide deletion or exchange (point mutations) were found in the microsatellite flanking regions

    Conductance of graphene nanoribbon junctions and the tight binding model

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    Planar carbon-based electronic devices, including metal/semiconductor junctions, transistors and interconnects, can now be formed from patterned sheets of graphene. Most simulations of charge transport within graphene-based electronic devices assume an energy band structure based on a nearest-neighbour tight binding analysis. In this paper, the energy band structure and conductance of graphene nanoribbons and metal/semiconductor junctions are obtained using a third nearest-neighbour tight binding analysis in conjunction with an efficient nonequilibrium Green’s function formalism. We find significant differences in both the energy band structure and conductance obtained with the two approximations

    Theoretical Study on Transport Properties of Normal Metal - Zigzag Graphene Nanoribbon - Normal Metal Junctions

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    We investigate transport properties of the junctions in which the graphene nanoribbon with the zigzag shaped edges consisting of the NN legs is sandwiched by the two normal metals by means of recursive Green's function method. The conductance and the transmission probabilities are found to have the remarkable properties depending on the parity of NN. The singular behaviors close to E=0 with EE being the Fermi energy are demonstrated. The channel filtering is shown to occur in the case with N=N= even.Comment: 4 pages, 5 figure

    Phase 1 dose-escalation study of S-222611, an oral reversible dual tyrosine kinase inhibitor of EGFR and HER2, in patients with solid tumours.

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    BACKGROUND: S-222611 is a reversible inhibitor of EGFR, HER2 and HER4 with preclinical activity in models expressing these proteins. We have performed a Phase 1 study to determine safety, maximum tolerated dose (MTD), pharmacokinetic profile (PK) and efficacy in patients with solid tumours expressing EGFR or HER2. PATIENTS AND METHODS: Subjects had advanced tumours not suitable for standard treatment, expressing EGFR or HER2, and/or with amplified HER2. Daily oral doses of S-222611 were escalated from 100mg to 1600 mg. Full plasma concentration profiles for drug and metabolites were obtained. RESULTS: 33 patients received S-222611. It was well tolerated, and the most common toxicities, almost all mild (grade 1 or 2), were diarrhoea, fatigue, rash and nausea. Only two dose-limiting toxicities occurred (diarrhoea and rash), which resolved on interruption. MTD was not reached. Plasma exposure increased with dose up to 800 mg, exceeding levels eliciting pre-clinical responses. The plasma terminal half-life was more than 24h, supporting once daily dosing. Responses were seen over a wide range of doses in oesophageal, breast and renal tumours, including a complete clinical response in a patient with HER2-positive breast carcinoma previously treated with lapatinib and trastuzumab. Four patients have remained on treatment for more than 12 months. Downregulation of pHER3 was seen in paired tumour biopsies from a responding patient. CONCLUSIONS: Continuous daily oral S-222611 is well tolerated, modulates oncogenic signalling, and has significant antitumour activity. The recommended Phase 2 dose, based on PK and efficacy, is 800 mg/day.The authors acknowledge financial support from the UK Department of Health via the National Institute for Health Research (NIHR) Biomedical Research Centre (BRC) award to Guy’s & St Thomas’ NHS Foundation Trust in partnership with King’s College London and King’s College Hospital NHS Foundation Trust (and NIHR Clinical Research Facility), and to The University of Cambridge and Cambridge University Hospital NHS Foundation Trust. Cambridge, King’s College London, and Newcastle are Experimental Cancer Medicine Centres.This is the accepted manuscript. The final version is available from http://www.sciencedirect.com/science/article/pii/S0959804914010922

    Imaging Bulk and Edge Transport near the Dirac Point in Graphene Moiré Superlattices.

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    Van der Waals structures formed by aligning monolayer graphene with insulating layers of hexagonal boron nitride exhibit a moiré superlattice that is expected to break sublattice symmetry. Despite an energy gap of several tens of millielectronvolts opening in the Dirac spectrum, electrical resistivity remains lower than expected at low temperature and varies between devices. While subgap states are likely to play a role in this behavior, their precise nature is unclear. We present a scanning gate microscopy study of moiré superlattice devices with comparable activation energy but with different charge disorder levels. In the device with higher charge impurity (∼1010 cm-2) and lower resistivity (∼10 kΩ) at the Dirac point we observe current flow along the graphene edges. Combined with simulations, our measurements suggest that enhanced edge doping is responsible for this effect. In addition, a device with low charge impurity (∼109 cm-2) and higher resistivity (∼100 kΩ) shows subgap states in the bulk, consistent with the absence of shunting by edge currents.This work was partly supported by EPSRC EP/L020963/1, JST CREST Grant Numbers JPMJCR15F3 and JSPS KAKENHI Grant Numbers JP25107003, JP25107004, JP26248061, JP15H01010, JP16H00982
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