1,266 research outputs found

    Update of the stranger story: the strange vector form factors of the nucleon

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    The strange vector form factors are investigated in the framework of the semi-bosonized SU(3) Nambu-Jona-Lasinio model (or chiral quark-soliton model). The mean-square strange radius \langle r^2 \rangle_s=-0.17\; \mbox{fm}^2 and the strange magnetic moment \mu_s = -0.45 are obtained in case of the constituent quark mass M=420 \;\mbox{MeV}. The results are compared with several different models

    Transmission and Reflection of Collective Modes in Spin-1 Bose-Einstein Condensate

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    We study tunneling properties of collective excitations in spin-1 Bose-Einstein condensates. In the absence of magnetic fields, the total transmission in the long wavelength limit occurs in all kinds of excitations but the quadrupolar spin mode in the ferromagnetic state. The quadrupolar spin mode alone shows the total reflection. A difference between those excitations comes from whether the wavefunction of an excitation corresponds to that of the condensate in the long wavelength limit. The correspondence results in the total transmission as in the spinless BEC.Comment: 6 pages, 5 figure

    Combination of gastric atrophy, reflux symptoms and histological subtype indicates two distinct aetiologies of gatric cardia cancer.

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    <b>INTRODUCTION</b> Atrophic gastritis is a risk factor for non-cardia gastric cancer, and gastro-oesophageal reflux disease (GORD) for oesophageal adenocarcinoma. The role of atrophic gastritis and GORD in the aetiology of adenocarcinoma of the cardia remains unclear. We have investigated the association between adenocarcinoma of the different regions of the upper gastrointestinal tract and atrophic gastritis and GORD symptoms. <b>METHODS</b> 138 patients with upper GI adenocarcinoma and age and sex matched controls were studied. Serum pepsinogen I/II was used as a marker of atrophic gastritis and categorised to five quintiles. History of GORD symptoms, smoking and H.pylori infection was incorporated in logistic regression analysis. Lauren classification of gastric cancer was used to subtype gastric and oesophageal adenocarcinoma. <b>RESULTS</b> Non-cardia cancer was associated with atrophic gastritis but not with GORD symptoms; 55% of these cancers were intestinal subtype. Oesophageal adenocarcinoma was associated with GORD symptoms, but not with atrophic gastritis; 84% were intestinal subtype. Cardia cancer was positively associated with both severe gastric atrophy [OR, 95% CI: 3.92 (1.77 – 8.67)] and with frequent GORD symptoms [OR, 95% CI: 10.08 (2.29 – 44.36)] though the latter was only apparent in the nonatrophic subgroup and in the intestinal subtype. The association of cardia cancer with atrophy was stronger for the diffuse versus intestinal subtype and this was the converse of the association observed with non-cardia cancer. <b>CONCLUSION</b> These findings indicate two distinct aetiologies of cardia cancer, one arising from severe atrophic gastritis and being of intestinal or diffuse subtype similar to non-cardia cancer, and one related to GORD and intestinal in subtype, similar to oesophageal adenocarcinoma. Gastric atrophy, GORD symptoms and histological subtype may distinguish between gastric versus oesophageal origin of cardia cancer

    Calcospherites in Rabbit Incisor Predentin

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    Calcospherites from the lower incisor dentin of rabbits were investigated by scanning and transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) and electron diffraction analyses. In the labial predentin, globular calcospherites of 8-31 μm were present at the root apex, decreasing in size toward the incisal region. The calcospherites at the intermediate region were of mulberry- as well as of spindle-shape of 1.5-4 μm diameter. The incisal pulp horn contained micro-calcospherites of 0.3-0.6 μmin diameter. In the lingual predentin, small granular calcospherites of 1. 8-3 μm were present at the root apex, increasing in size toward the intermediate region. Ultrathin sections of globular calcospherites showed bundles of collagen fibrils at the root apex of the labial predentin. The diameters of individual bundles ranged from 1.2-3.4 μm. The width of the fibrils in the bundles was approximately 120-170 nm. Bundles of collagen fibrils were not found in the lingual predentin. Crystals of calcospherites were identified as apatite by electron diffraction. Those at the intermediate region showed preferred orientation of the c-axis. TEM-EDS analyses indicated that Ca and P were the major elements, with small amounts of Mg. The Mg/Ca molar ratios decreased from the root apex to the incisal pulp horn. Ca peak intensities increased from the root apex to the incisal region

    Development of Skin Surface Radiation Detector System to Monitor Positron Emission Tomography

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    開始ページ、終了ページ: 冊子体のページ付

    Estimation of Organ Biodistribution of Activities in Human from External Measurement with TLD

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    開始ページ、終了ページ: 冊子体のページ付

    Towards first-principles understanding of the metal-insulator transition in fluid alkali metals

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    By treating the electron-ion interaction as perturbation in the first-principles Hamiltonian, we have calculated the density response functions of a fluid alkali metal to find an interesting charge instability due to anomalous electronic density fluctuations occurring at some finite wave vector {\bi Q} in a dilute fluid phase above the liquid-gas critical point. Since |{\bi Q}| is smaller than the diameter of the Fermi surface, this instability necessarily impedes the electric conduction, implying its close relevance to the metal-insulator transition in fluid alkali metals.Comment: 11 pages, 5 figure
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