475 research outputs found

    Chiral SU(3) theory of antikaon-nucleon interactions with improved threshold constraints

    Full text link
    Kˉ\bar{K}-nucleon interactions are investigated in the framework of coupled-channels dynamics based on the next-to-leading order chiral SU(3) meson-baryon effective Lagrangian. A recent determination of the 1s shift and width of kaonic hydrogen enables us to set accurate constraints on the coupled-channels meson-baryon amplitudes in the strangeness S=1S=-1 sector. Theoretical uncertainties in the subthreshold extrapolation of the coupled-channels amplitudes are discussed. Using this framework, we give predictions for KK^--neutron interactions and for the spectrum of the Λ(1405)\Lambda(1405) resonance. A simplified, effective three-channel model using leading order chiral SU(3) meson-baryon interactions is also constructed for convenient application in Kˉ\bar{K}-nuclear few-body calculations.Comment: 24 pages, 7 figure

    Structural evolution of the Ongul Islands, Lutzow-Holm Complex, East Antarctica

    Get PDF
    We describe outcrop-scale folds at ten localities in the Ongul Islands, including five localities where interference patterns of more than two stages of folding are observed, along with structural data summarized in stereogram. F_(m-1) are recognized as isoclinal to rootless folds with fold axes trending NNW-SSE. S_(m-1) is defined by orthopyroxene, hornblende and biotite aligned parallel to the compositional layering and as axial planar foliation in F_(m-1) folds, and is folded by tight F_m. F_m have axial traces that trend NNW-SSE and subvertical axial planes dipping ENE and striking NNW-SSE. Axial planar foliation S_m is defined by biotite and hornblende in the hinges of F_m. F_(m-1) axes typically trend parallel to F_m axes and can be discriminated only in areas showing interference patterns. F_(m+1) are gentle to open with axes trending approximately N-S. Boudinage formed before Dm and interboudin partitions are filled with orthopyroxene-bearing leucosome. Judging from minerals constituting D_(m-1) and D_m structures, D_(m-1) occurred under granulite-facies conditions and at least part of D_m probably under amphibolite-facies conditions

    Structural analysis of the Lutzow-Holm Complex in Akarui Point, East Antarctica, and overview of the complex

    Get PDF
    Two phases of major deformation are responsible for the dominant structures at Akarui Point, Prince Olav Coast, East Antarctica. The first phase, referred to as D_(m-1), is associated with the formation of foliation defined by biotite and hornblende aligned sub-parallel to compositional layering. The foliation is locally parallel to the axial planes of isoclinal and intrafolial folds of gneissic layers. Boudins are present with long axes subparallel to the axes of F_(m-1) folds. A second phase of deformation, denoted as D_m, produced a crenulation lineation and axial planar foliation that trends NW-SE throughout the area. This foliation is parallel to the axial plane of the large-scale Akarui Point Synform, which has a fold axis plunging gently SE, suggesting that the Akarui Point Synform formed during D_m. A locally-developed third phase of deformation (D_(m+1)) produced gentle folding of S_(m-1) and S_m. Chemical compositions of biotite grains that define S_(m-1) and S_m are similar. Migmatite shows close associations with D_(m-1) and D_m structures. This suggests that both phases of deformation were contemporaneous with high-grade metamorphism. Compilation of structural data in other areas reveals that D_(m-1) and D_m controlled dominant structures of the Lutzow-Holm Complex. Several folding events after D_m may be responsible for differing orientations of D_m structures between localities

    Timing of ductile deformation and peak metamorphism in Skallevikshalsen, Lutzow-Holm Complex, East Antarctica

    Get PDF
    The geological structures of Skallevikshalsen, Lutzow-Holm Complex, East Antarctica are mainly controlled by two stages of ductile deformation, D_(m-1) and D_m. The D_(m-1) stage is characterized by the development of isoclinal F_(m-1) folds with fold axes gently plunging ENE or SWS, and axial planes parallel to the compositional layering (S_(m-1)) of the metamorphic rocks. The D_m stage is characterized by the development of tight folds with axes parallel to F_(m-1) and almost vertical axial planes. An axial planar foliation, S_m, defined by the alignment of biotite and hornblende, is formed in the hinges of F_m folds. No change in direction of elongation took place between D_(m-1) and D_m. Microstructural study and field observations show that a stretching lineation on S_(m-1) defined by the alignment of sillimanite was formed during D_(m-1). The alignment of sillimanite inclusions in garnet rims probably corresponds to an older schistosity formed during D_(m-2), which had a different orientation of principal strain axes than those of D_(m-1) and D_m. Peak metamorphic mineral assemblages are preserved in garnet cores, and their formation is considered to predate D_(m-2). Absence of the alignment of inclusions in garnet cores suggests that peak metamorphism was attained under conditions without strong deformation

    Structure of Lambda(1405) and threshold behavior of piSigma scattering

    Full text link
    The scattering length and effective range of the piSigma channel are studied in order to characterize the strangeness S=-1 meson-baryon scattering and the Lambda(1405) resonance. We examine various off-shell dependence of the amplitude in dynamical chiral models to evaluate the threshold quantities with the constraint at the KbarN threshold. We find that the piSigma threshold parameters are important to the structure of the Lambda(1405) resonance and provide further constraints on the subthreshold extrapolation of the KbarN interaction.Comment: 20 pages, 4 figures, with corrections made after referring proces

    Electrochemical surface plasmon resonance as a probe of redox reactions at the ionic liquid|gold interface

    Get PDF
    Electrochemical surface plasmon resonance (ESPR) has been employed as a probe of redox reactions at the interface between gold (Au) and ionic liquid (IL). Two redox couples, ferrocene (Fc)/Fc⁺ and (ferrocenylmethyl)trimethylammonium (FTA⁺)/FTA²⁺, and two ILs, trioctylmethylammonium bis(trifluoromethanesulfonyl)amide ([TOMA⁺][C₁C₁N⁻]) have been studied. In the ESPR measurements, the shift of the SPR angle has been recorded simultaneously with cyclic voltammogram (CV). It has been revealed that the SPR angle shift reproduces CV when the former is semi-differentiated or the latter is semi-integrated, and, therefore, that the ESPR response probes the surface concentration of redox couples at the IL|Au interface. Among the four combination of the two redox couples and the two ILs, the case for Fc/Fc⁺ in [TOMA⁺][C₁C₁N⁻] shows significantly greater ESPR response than the other three cases. A model has been established for the relationship between the SPR angle shift and the surface concentration of redox species. The model predicts that the SPR angle shift becomes pronounced with increasing DR/DO, the diffusion coefficient ratio of the reduced (R) and oxidized (O) species when the reduced species is initially dissolved in the IL as is the case for the present study. Significantly greater DR/DO for Fc/Fc⁺ in [TOMA⁺][C₁C₁N⁻] than the three other cases has been confirmed from the DR and DO measurements by CV with a microdisk electrode. The trend of the measured DR and DO values agrees with recent findings by researchers that small neutral solutes in ILs composed of large ions diffuse fast beyond the prediction of the Stokes-Einstein relation

    Projecting XRP price burst by correlation tensor spectra of transaction networks

    Get PDF
    Cryptoassets are becoming essential in the digital economy era. XRP is one of the large market cap cryptoassets. Here, we develop a novel method of correlation tensor spectra for the dynamical XRP networks, which can provide an early indication for XRP price. A weighed directed weekly transaction network among XRP wallets is constructed by aggregating all transactions for a week. A vector for each node is then obtained by embedding the weekly network in continuous vector space. From a set of weekly snapshots of node vectors, we construct a correlation tensor. A double singular value decomposition of the correlation tensors gives its singular values. The significance of the singular values is shown by comparing with its randomize counterpart. The evolution of singular values shows a distinctive behavior. The largest singular value shows a significant negative correlation with XRP/USD price. We observe the minimum of the largest singular values at the XRP/USD price peak during the first week of January 2018. The minimum of the largest singular value during January 2018 is explained by the decomposing the correlation tensor in the signal and noise components and also by evolution of community structure.Comment: 12 pages 8 figures, Supplementary Information: 4 pages, 6 figure

    Treatment of Large Liver Cyst Evaluated with CA19-9 in the Cystic Fluid

    Get PDF
    A middle-aged woman was admitted with a diagnosis of liver cysts. The patient was symptomatic and was treated by injecting absolute ethanol into the largest cyst every week, but the secretion from the cyst persisted. The patient was then treated by absolute ethanol injection every day with good results. CA 19-9 was measured in the cystic fluid. The secretion was related to CA 19-9 activity

    Geochronological study of post-metamorphic granite from Kasumi Rock, Lutzow-Holm Complex, East Antarctica

    Get PDF
    Kasumi Rock is situated in the amphibolite-facies metamorphic zone in the Lutzow-Holm Complex, East Antarctica. In this area, granitic rocks occur as steeply dipping linear dykes with sharp intrusive contacts, and cross-cut the foliation of layered metamorphic rocks. A geochronological study of this post-metamorphic granite (PMG) has been performed. An Rb-Sr whole rock isochron for five granitic rocks defines an age of 492.1+-23.4 Ma with an initial ^87Sr/^86Sr ratio of 0.70535+-0.00027 (MSWD=0.08). In the Sm-Nd isochron diagram, four rock samples yield an age of 498.4+-90.6 Ma with an initial ^143Nd/^144Nd ratio of 0.511782+-0.000101 (MSWD=0.05). The whole rock isochron ages and mode of occurrence suggest that the Kasumi PMGs were intruded after regional cooling of the area, and probably affected local reequilibrium for isotopic systems of surrounding metamorphic rocks. The PMGs might have been slowly cooled and crystallized after the intrusion. The Kasumi PMGs have no genetic relation to the Oku-iwa PMGs as regards Rb-Sr and Sm-Nd isotopic systems, because the initial ratios of both PMGs are quite different from each other. This is interpreted to mean that the PMGs in the Lutzow-Holm Complex were originated from different source materials or had different chemical reaction processes with crustal materials
    corecore