629 research outputs found

    Antisymmetrized Molecular Dynamics with Coherent State Pion and Its Application to Excited Spectrum of 12C

    Full text link
    We have introduced coherent state neutral pion into Antisymmetrized Molecular Dynamics. With the aid of coherent state technique, it becomes possible to calculate transition matrix elements of the pion field operator and to study excited states containing pions. For large pion-nucleon coupling fpiN > 1.6, pions have a finite expectation value and bring large energy gain in 12C. We discuss two aspects of pionic effects in spectroscopy; the LS interaction like effect and the mixing of different nucleon parity states, which would modify low energy nuclear levels.Comment: 10 pages, 3 figure

    Fibril Formation by Glucagon in Solution and in Membrane Environments

    Get PDF
    Glucagon is a 29-amino acid peptide hormone secreted by pancreatic α-cells and interacts with specific receptors located in various organs. Glucagon tends to form gel-like fibril aggregates that are cytotoxic because they activate apoptotic signaling pathways. First, fibril formation by glucagon in acidic solution is discussed in light of morphological and structural changes during elapsed time. Second, we provide kinetic analyses using a two-step autocatalytic reaction mechanism; the first step is a homogeneous nuclear formation process, and the second step is an autocatalytic heterogeneous fibril elongation process. Third, the processes of fibril formation by glucagon in a membrane environment are discussed based on the structural changes in the fibrils. In the presence of bicelles in acidic solution, glucagon interacts with the bicelles and forms fibril intermediates on the bicelle surface and grows into elongated fibrils. Glucagon-dimyristoylphosphatidylcholine (DMPC) bilayers in neutral solution mimic the environment for fibril formation by glucagon under near-physiological condition. Under these conditions, glucagon forms fibril intermediates that grow into elongated fibrils inside the lipid bilayer. Many days after preparing the glucagon-DMPC bilayer sample, the fibrils form networks inside and outside the bilayer. Furthermore, fibril intermediates strongly interact with lipid bilayers to form small particles

    Discovery of Multiple High-Velocity Narrow Circumstellar Na I D Lines in Nova V1280 Sco

    Full text link
    We discovered multiple high-velocity (ranging from -900 to -650 km/s) and narrow (FWHM = 15 km/s) absorption components corresponding to both the D2 and the D1 lines of Na I on a high dispersion spectrum of V1280 Sco observed on 2009 May 9 (UT), 814 d after the V-band maximum. Subsequent observations carried out on 2009 June and July confirmed at least 11 distinct absorption components in both systems. Some components had deepened during the two months period while their HWHMs and wavelengths remained nearly constant. We suggest these high velocity components originate in cool clumpy gas clouds moving on the line of sight, produced in interactions between pre-existing cool circumstellar gas and high velocity gas ejected in the nova explosion. The optical region spectrum of V1280 Sco in 2009 is dominated by the continuum radiation and exhibits no forbidden line characterizing the nebular phase of typical novae. Permitted Fe II lines show doubly peaked emission profiles and some strong Fe II lines are accompanied by a blue shifted (about -255 km/s) absorption component. However, no high-velocity and narrow components corresponding to those of Na I could be detected in Fe II lines nor in the Balmer lines. The 255 km/s low velocity absorption component is most probably originating in the wind from the nova.Comment: Accepted for PASJ letter, 5 pages, 8 figure

    Relationship between radiographic grading of osteoarthritis and the biochemical markers for arthritis in knee osteoarthritis

    Get PDF
    The aim of this study was to investigate the relationship between the biochemical markers of arthritis and the radiographic grading of osteoarthritis (OA) in knees. Seventy-one women aged 49–85 years with knee OA were studied. Anterior–posterior knee radiographs and hand radiographs were taken in all patients. The radiographic grading of OA in the knee was performed by using the Kellgren–Lawrence criteria and the joint space width. The 71 patients with knee OA were divided into two groups: 37 patients exhibiting generalized osteoarthritis (GOA) and 34 non-GOA patients, according to the grading of their hand radiograph. C-reactive protein (CRP), urinary pyridinoline, YKL-40, plasma matrix metalloproteinase (MMP)-3, MMP-9 and tissue inhibitor of metalloproteinases (TIMP)-1 were measured as the biochemical markers of arthritis. The radiographic grading with the Kellgren–Lawrence scale revealed a significant relationship to the joint space width (P = 0.003): the joint space width decreased with increasing Kellgren–Lawrence grade. All biochemical markers had negative correlations with the joint space width, but only urinary pyridinoline had a significant correlation (P = 0.039). Pyridinoline (P = 0.034) and TIMP-1 (P = 0.017) also exhibited a significant relationship to the Kellgren–Lawrence grade. In GOA evaluations, the joint space width did not differ between GOA and non-GOA patients. CRP, pyridinoline, YKL-40 and MMP-3 levels were significantly greater in GOA patients than in non-GOA patients. CRP, pyridinoline, YKL-40, MMP-3 and TIMP-1 levels each related to at least one of the radiographic gradings. Furthermore, pyridinoline related to every type of radiographic grading examined in the present study

    Science linkages in technologies patented in Japan

    Get PDF
    We constructed an original database concerning science linkages based on text of Japanese Patent Gazette published since 1994. We discovered that Japanese inventers cite many academic papers in the texts of the patent applications in the Japanese Patent System. Based on this finding, we constructed science citation index by data mining the texts of Japanese patent system for the first time. First, more than 880,000 patent data classified into about 600 categories. Then, we extracted non-patent references from all the granted patents and counted the number of them. This number shows the strength of the linkage between science and technology and therefore is called "science linkage index." The science linkage indexes among different patent classifications differ significantly from each other. The technologies related to bio -technology were by far the closest to science. It suggests that the process of creating new technology differs from technology to technology.

    Effects of Consuming Xylitol on Gut Microbiota and Lipid Metabolism in Mice

    Get PDF
    The sugar alcohol xylitol inhibits the growth of some bacterial species including Streptococcus mutans. It is used as a food additive to prevent caries. We previously showed that 1.5–4.0 g/kg body weight/day xylitol as part of a high-fat diet (HFD) improved lipid metabolism in rats. However, the effects of lower daily doses of dietary xylitol on gut microbiota and lipid metabolism are unclear. We examined the effect of 40 and 200 mg/kg body weight/day xylitol intake on gut microbiota and lipid metabolism in mice. Bacterial compositions were characterized by denaturing gradient gel electrophoresis and targeted real-time PCR. Luminal metabolites were determined by capillary electrophoresis electrospray ionization time-of-flight mass spectrometry. Plasma lipid parameters and glucose tolerance were examined. Dietary supplementation with low- or medium-dose xylitol (40 or 194 mg/kg body weight/day, respectively) significantly altered the fecal microbiota composition in mice. Relative to mice not fed xylitol, the addition of medium-dose xylitol to a regular and HFD in experimental mice reduced the abundance of fecal Bacteroidetes phylum and the genus Barnesiella, whereas the abundance of Firmicutes phylum and the genus Prevotella was increased in mice fed an HFD with medium-dose dietary xylitol. Body composition, hepatic and serum lipid parameters, oral glucose tolerance, and luminal metabolites were unaffected by xylitol consumption. In mice, 40 and 194 mg/kg body weight/day xylitol in the diet induced gradual changes in gut microbiota but not in lipid metabolism

    Architecture of the Subendothelial Elastic Fibers of Small Blood Vessels and Variations in Vascular Type and Size

    Get PDF
    Most blood vessels contain elastin that provides the vessels with the resilience and flexibility necessary to control hemodynamics. Pathophysiological hemodynamic changes affect the remodeling of elastic components, but little is known about their structural properties. The present study was designed to elucidate, in detail, the three-dimensional (3D) architecture of delicate elastic fibers in small vessels, and to reveal their architectural pattern in a rat model. The fine vascular elastic components were observed by a newly developed scanning electron microscopy technique using a formic acid digestion with vascular casts. This method successfully visualized the 3D architecture of elastic fibers in small blood vessels, even arterioles and venules. The subendothelial elastic fibers in such small vessels assemble into a sheet of meshwork running longitudinally, while larger vessels have a higher density of mesh and thicker mesh fibers. The quantitative analysis revealed that arterioles had a wider range of mesh density than venules; the ratio of density to vessel size was higher than that in venules. The new method was useful for evaluating the subendothelial elastic fibers of small vessels and for demonstrating differences in the architecture of different types of vessels
    • …
    corecore