259 research outputs found

    Electromagnetic Form Factors of Nucleons with QCD Constraints Sytematic Study of the Space and Time-like Regions

    Full text link
    Elastic electromagnetic form factors of nucleons are investigated both for the time-like and the space-like momentums under the condition that the QCD constraints are satisfied asymptotically. The unsubtracted dispersion relation with the superconvergence conditions are used as a realization of the QCD conditions. The experimental data are analyzed by using the dispersion formula and it is shown that the calculated form factors reproduce the experimental data reasonably well.Comment: 14 page

    Morphological Observations of Rabbit Gastric Fundus Cells in Primary Culture

    Get PDF
    The morphological properties of the cells isolated from rabbit gastric fundus and the cells grown on a collagen gel sheet were investigated, using both light and scanning electron microscopes. The cells used for this study were obtained in the form of lumps from the isthmus region. The lumps consisted of 4 different types of cells (mucous and immatured cells, and a small number of chief and parietal cells). These isolated cells were then grow on collagen gel in a defined medium. However, two of those cells (chief and parietal cells) gradually disappeared as the culture time progressed. The majority of the cells grown on the gel were found to be mucous and assorted unidentified cells. The mucous cells were covered with many short microvilli, and many PAS positive granules in their cytoplasm. Some of those cells were covered with a mucous like substance. Judging from the staining properties of each cell, the unidentified cells appeared to indicate that they were immature cells. It was found that the cell's morphology and population retained constant regardless of whether Bh-EGF was administered or not

    Cytoprotective Activity of Components of Garlic, Ginseng and Ciuwjia on Hepatocyte Injury Induced by Carbon Tetrachloride In Vitro

    Get PDF
    The antihepatotoxic activity of ten components related to plants were investigated using freshly isolated hepatocytes which maintained specific liver functions such as glucagon-dependent glycogenolysis and albumin producibility. Six components of garlic, i.e., S-methyl cysteine, S-ethyl cysteine, S-propyl cysteine, S-allylmercapto cysteine, alliin and S-allyl cysteine, and two syringaresinols of ciuwjia were synthesized. Two ginsenosides were purified from extract of ginseng. Both syringaresinols and S-allyl cysteine at concentrations of 250ng/ml and 0.5μg/ml, respectively, completely suppressed cytotoxicity on hepatocytes by CC14, as judged from GPT level released in the culture medium and morphology of the hepatocytes in stained specimens. The same was observed with S-propyl cysteine, S-allylmercapto cysteine and two ginsenosides at concentrations of lOμg/ml or less. Alliin was also effective but suppressed only GPT leakage. Four positive control drugs used was less effective. S-methyl cysteine and S-ethyl cysteine showed no obvious effect in any concentrations

    Fabrication of metal coated carbon nanotubes by electroless deposition for improved wettability with molten aluminum

    Get PDF
    Ni-P alloy coated and Au/Ni-P alloy double-coated multiwalled carbon nanotubes (MWCNTs) were fabricated using electroless plating. Three types of electroless Ni-P alloy plating baths were prepared to coat the MWCNTs with Ni-P alloy films of varying phosphorus content. Electroless gold coating of the Ni-P alloy coated MWCNTs was also carried out using a non-cyanide bath. The microstructures of the coatings on the MWCNTs were examined by scanning electron microscopy and X-ray diffraction. The wettability of the metal-coated MWCNTs with molten aluminum was also evaluated. MWCNTs coated with Ni-P alloy films containing 9-25 at.% phosphorus content were fabricated by electroless deposition. Electroless gold deposition on the Ni-P alloy coated MWCNTs to form Au/Ni-P alloy double-coated MWCNTs was also possible. The wettability of the metal-coated MWCNTs with molten aluminum was significantly improved compared to that of non-coated MWCNTs. The coating metals of the MWCNTs dissolved into the molten aluminum, resulting in good wettability between the MWCNTs and molten aluminum and dispersion of the resulting bare MWCNTs in the aluminum matrix. The dissolved coating metals formed stable compounds with molten aluminum.ArticleSURFACE & COATINGS TECHNOLOGY. 212:207-213 (2012)journal articl

    On-demand transfer of trapped photons on a chip

    Get PDF
    チップ上の微小点に保存した光の瞬時転送. 京都大学プレスリリース. 2016-05-26.Photonic crystal nanocavities, which have modal volumes of the order of a cubic wavelength in the material, are of great interest as flexible platforms for manipulating photons. Recent developments in ultra-high quality factor nanocavities with long photon lifetimes have encouraged us to develop an ultra-compact and flexible photon manipulation technology where photons are trapped in networks of such nanocavities. The most fundamental requirement is the on-demand transfer of photons to and from the trapped states of arbitrary nanocavities. We experimentally demonstrate photon transfer between two nearly resonant nanocavities at arbitrary positions on a chip, triggered by the irradiation of a third nonresonant nanocavity using an optical control pulse. We obtain a high transfer efficiency of ~90% with a photon lifetime of ~200 ps

    A Morphological Study of Electroless Deposition in High Magnetic Fields(Crystal Growth, Chemical Reaction and Biology)

    Get PDF
    Growth morphology of a silver metal-leaf was investigated in high magnetic fields up to 8T as an experimental approach to the diffusion-limited aggregation (DLA) with the lateral drift of particles. The silver metal-leaves were grown around a square \u27seed\u27 of copper from a AgNO_3 aqueous solution by means of the electroless reduction of silver ions. The growth pattern of the metal-leaf had a typical DLA structure with the fractal dimension of 1.62 in the absence of magnetic field. On the other hand, it had a spiral and dense branching structure at 8T, in which the crossover in the fractal dimension from 1.69 to 2 was observed with increasing length scale. The spiral direction was reversed by the reversal of the applied field. A metal-forest pattern of silver was also investigated, which was grown around a copper ribbon. Its growth morphology changed from the DLA pattern without the field into a canting and dense pattern at 8T

    Impact of Right Ventricular Dilatation in Patients with Atrial Septal Defect

    Get PDF
    Objective. The aim of this study was to examine the relationship between right ventricular (RV) volume and exercise capacity in adult patients with atrial septal defect (ASD) and to determine the degree of RV dilatation for transcatheter ASD closure. Background. RV dilatation is an indication of transcatheter ASD closure; however, few studies have reported the clinical significance of RV dilatation. Methods. We enrolled 82 consecutive patients (mean age, 49 +/- 18 years; female, 68%) who underwent cardiac magnetic resonance imaging and symptom-limited cardiopulmonary exercise test before ASD closure. The relationship between RV volume and peak oxygen uptake (VO2) was evaluated. Results. The mean RV end-diastolic volume index was 108 +/- 27 ml/m(2) (range, 46 to 180 ml/m(2)). The mean peak VO2 was 24 +/- 7 ml/min/kg (range, 14 to 48 ml/min/kg), and the mean predicted peak VO2 was 90 +/- 23%. There were significant negative relationships of RV end-diastolic volume index with peak VO2 (r = -0.28, p= 120 ml/m(2) was related to the reduction in peak VO2. This criterion of RV dilatation may be valuable for the indication of transcatheter ASD closure

    PHB2 Protects Sister-Chromatid Cohesion in Mitosis

    Get PDF
    SummaryCohesion between sister chromatids is essential for proper chromosome segregation in mitosis. In vertebrate mitotic cells, most cohesin is removed from the chromosome arms [1–4], but centromeric cohesin is protected by shugoshin until the onset of anaphase [5]. However, the mechanism of this protection of centromeric cohesion is not well understood. Here, we demonstrate that prohibitin 2 (PHB2) is involved in the regulation of sister-chromatid cohesion during mitosis in HeLa cells. PHB2 is an evolutionarily conserved protein in eukaryotes and has multiple functions, such as transcriptional regulation and cell viability and development [6–8]. However, its functions in mitosis have not yet been determined. We show that depletion of PHB2 by RNA interference (RNAi) causes premature sister-chromatid separation and defects in chromosome congression accompanied by mitotic arrest by spindle-checkpoint activation. In the absence of PHB2, cohesin is dissociated from centromeres during early mitosis, although the centromeric localization of shugoshin is preserved. Thus, our findings suggest that, in addition to the shugoshin, PHB2 is also required to protect the centromeric cohesion from phosphorylation by Plk1 during early mitosis and that its function is essential for proper mitotic progression
    corecore