470 research outputs found

    Relativization in Dàgáárè and its typological implications: Left-headed but internally-headed

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    This article examines in detail the syntax of relativization in Dàgáárè, a Mabia (Oti-Volta) language of the Gur branch in the Niger-Congo family. The main aims of our investigation are twofold. The first is to describe a cluster of typologically interesting syntactic features of relativization in Dàgáárè in the light of the fact that no detailed description exists in the literature. The second is to demonstrate that relative clauses in Dàgáárè are head-internal relative clauses (HIRCs), even though they are, on the surface, postnominal relative clauses, like those in English. Thus, they are not of the in-situ type of HIRC that is well known in the literature. We call this type of relative clause a left-headed HIRC. This type of relativization has rarely been noticed cross-linguistically in the previous literature and therefore is of considerable significance for general linguistics, linguistic typology, as well as theoretical linguistics. Evidence comes from coordination in possessor relativization and PP relativization. Our discovery shows that Universal Grammar allows left-headed HIRCs as an option in addition to the more familiar types: in-situ HIRCs and head-external relative clauses (HERCs). © 2009 Elsevier B.V. All rights reserved.postprin

    Longitudinal Eigenvibration of Multilayer Colloidal Crystals and the Effect of Nanoscale Contact Bridges

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    Longitudinal contact-based vibrations of colloidal crystals with a controlled layer thickness are studied. These crystals consist of 390 nm diameter polystyrene spheres arranged into close packed, ordered lattices with a thickness of one to twelve layers. Using laser ultrasonics, eigenmodes of the crystals that have out-of-plane motion are excited. The particle-substrate and effective interlayer contact stiffnesses in the colloidal crystals are extracted using a discrete, coupled oscillator model. Extracted stiffnesses are correlated with scanning electron microscope images of the contacts and atomic force microscope characterization of the substrate surface topography after removal of the spheres. Solid bridges of nanometric thickness are found to drastically alter the stiffness of the contacts, and their presence is found to be dependent on the self-assembly process. Measurements of the eigenmode quality factors suggest that energy leakage into the substrate plays a role for low frequency modes but is overcome by disorder- or material-induced losses at higher frequencies. These findings help further the understanding of the contact mechanics, and the effects of disorder in three-dimensional micro- and nano-particulate systems, and open new avenues to engineer new types of micro- and nanostructured materials with wave tailoring functionalities via control of the adhesive contact properties

    Complex Contact-Based Dynamics of Microsphere Monolayers Revealed by Resonant Attenuation of Surface Acoustic Waves

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    Contact-based vibrations play an essential role in the dynamics of granular materials. Significant insights into vibrational granular dynamics have previously been obtained with reduced-dimensional systems containing macroscale particles. We study contact-based vibrations of a two-dimensional monolayer of micron-sized spheres on a solid substrate that forms a microscale granular crystal. Measurements of the resonant attenuation of laser-generated surface acoustic waves reveal three collective vibrational modes that involve displacements and rotations of the microspheres, as well as interparticle and particle-substrate interactions. To identify the modes, we tune the interparticle stiffness, which shifts the frequency of the horizontal-rotational resonances while leaving the vertical resonance unaffected. From the measured contact resonance frequencies we determine both particle-substrate and interparticle contact stiffnesses and find that the former is an order of magnitude larger than the latter. This study paves the way for investigating complex contact-based dynamics of microscale granular crystals and yields a new approach to studying micro- to nanoscale contact mechanics in multiparticle networks.National Science Foundation (U.S.) (Grant CMMI-1333858)United States. Army Research Office (Grant W911NF-15-1-0030)University of Washington. Royalty Research FoundationNational Science Foundation (U.S.) (Grant CHE-1111557

    Dynamics of a deformable self-propelled particle under external forcing

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    We investigate dynamics of a self-propelled deformable particle under external field in two dimensions based on the model equations for the center of mass and a tensor variable characterizing deformations. We consider two kinds of external force. One is a gravitational-like force which enters additively in the time-evolution equation for the center of mass. The other is an electric-like force supposing that a dipole moment is induced in the particle. This force is added to the equation for the deformation tensor. It is shown that a rich variety of dynamics appears by changing the strength of the forces and the migration velocity of self-propelled particle

    Collective Dynamics of Deformable Self-Propelled Particles with Repulsive Interaction

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    We investigate dynamics of deformable self-propelled particles with a repulsive interaction whose magnitude depends on the relative direction of elongation of a pair of particles. A collective motion of the particles appears in two dimensions. However this ordered state becomes unstable when the particle density exceeds a certain critical threshold and the dynamics becomes disorder. We show by a mean field analysis that this novel transition characteristic to deformability occurs due to a saddle-node bifurcation.Comment: 4 pages, 6 figure

    Siblicide and seniority.

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    This article uses samples of siblicide fro

    Effects of radiation damage caused by proton irradiation on Multi-Pixel Photon Counters (MPPCs)

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    We have investigated the effects caused by proton-induced radiation damage on Multi-Pixel Photon Counter (MPPC), a pixelized photon detector developed by Hamamatsu Photonics. The leakage current of irradiated MPPC samples linearly increases with total irradiated doses due to radiation damage, which is not completely recovered even after a year from the irradiation. No significant change has been observed in the gains at least up to 8.0 Gy (9.1×1079.1\times10^7 n/mm2^2 in 1 MeV neutron equivalent fluence, Φeq\Phi_{\rm eq}). The device has completely lost its photon-counting capability due to baseline fluctuations and noise pile-up after 21 Gy irradiation (2.4×1082.4\times10^8 n/mm2^2 in Φeq\Phi_{\rm eq}), which might be problematic for some applications, such as ring-imaging Cherenkov detectors. We have found that the pulse-height resolution has been slightly deteriorated after 42 Gy irradiation (4.8×1084.8\times10^8 n/mm2^2 in Φeq\Phi_{\rm eq}), where the measured sample has been illuminated with a few hundred photons. This effect should be considered in the case of energy-measurement applications.Comment: 18 pages, 10 figure

    Mutational Profile and Pathological Features of a Case of Interleukin-10 and RGS1-Positive Spindle Cell Variant Diffuse Large B-Cell Lymphoma

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    Diffuse large B-cell lymphoma with spindle cell morphology is a rare variant. We present the case of a 74-year-old male who initially presented with a right supraclavicular (lymph) node enlargement. Histological analysis showed a proliferation of spindle-shaped cells with narrow cytoplasms. An immunohistochemical panel was used to exclude other tumors, such as melanoma, carcinoma, and sarcoma. The lymphoma was characterized by a cell-of-origin subtype of germinal center B-cell-like (GCB) based on Hans’ classifier (CD10-negative, BCL6-positive, and MUM1-negative); EBER negativity, and the absence of BCL2, BCL6, and MYC rearrangements. Mutational profiling using a custom panel of 168 genes associated with aggressive B-cell lymphomas confirmed mutations in ACTB, ARID1B, DUSP2, DTX1, HLA-B, PTEN, and TNFRSF14. Based on the LymphGen 1.0 classification tool, this case had an ST2 subtype prediction. The immune microenvironment was characterized by moderate infiltration of M2-like tumor-associated macrophages (TMAs) with positivity of CD163, CSF1R, CD85A (LILRB3), and PD-L1; moderate PD-1 positive T cells, and low FOXP3 regulatory T lymphocytes (Tregs). Immunohistochemical expression of PTX3 and TNFRSF14 was absent. Interestingly, the lymphoma cells were positive for HLA-DP-DR, IL-10, and RGS1, which are markers associated with poor prognosis in DLBCL. The patient was treated with R-CHOP therapy, and achieved a metabolically complete response
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