646 research outputs found

    Effects of Instantons on the YN Interaction

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    We investigate the symmetric and anti-symmetric spin-orbit forces (SLS and ALS) of the effective Λ\LambdaN interaction derived from a quark cluster model with the instanton-induced interaction (\III), which can reproduce the observed YN cross sections as well as the observed NN scattering data. It is found that coupling to the Σ\SigmaN channel enhances Λ\LambdaN ALS, and therefore that the cancellation between SLS and ALS in the Λ\LambdaN channel becomes more complete. This may be one of the major reasons why the single-particle spin-orbit force of Λ\Lambda in nuclei is weak.Comment: 3 pages, 2 figures, FewBody XV

    The untangling theorem

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    AbstractWe show a tangle (B,t1,t2) is trivial if and only if π1(B−(t1⌣t2))≅Z∗Z, π1( B−t1)≅Z and π1(B−t2)≅Z. We use mainly the methods of the combinatorial group theory

    CP,T and/or CPT Violations in the K0-K0bar System --Implications of the KTeV,NA48 and CPLEAR Results

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    Possible violation of CP, T and/or CPT symmetries in the \ko-\kob system is studied from a phenomenological point of view. For this purpose, we first introduce parameters which represent violation of these symmetries in mixing parameters and decay amplitudes in a convenient and well-defined way and, treating these parameters as small, derive formulas which relate them to the experimentally measured quantities. We then perform numerical analyses, with the aid of the Bell-Steinberger relation, to derive constraints to these symmetry-violating parameters, firstly paying particular attention to the results reported by KTeV Collaboration and NA48 Collaboration, and then with the results reported by CPLEAR Collaboration as well taken into account. A case study, in which either CPT symmetry or T symmetry is assumed, is also carried out. It is demonstrated that CP and T symmetries are violated definitively at the level of 10^{-4} in 2π2\pi decays and presumably at the level of 10^{-3} in the \ko-\kob mixing, and that the Bell-Steinberger relation helps us to establish CP and T violations being definitively present in the \ko-\kob mixing and to test CPT symmetry to a level of 10^{-4} ~ 10^{-5}.Comment: 21 pages, 1 figure

    Serotonergic Neurotransmission in Autism Spectrum Disorders

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    Development of an Unnecessary Goods Reuse Information Offer System For Creating a Recycling Society

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    This research is built on the information offer system for reusing unnecessary articles for the purpose of creating a recycling society in Okayama University. This system can perform the registration on the web of for unnecessary goods, perusal, and references. This report mainly describes the outline of a recycling information offer system, the feature, composition, and its employment. The feature of this system is that all of intramural members can check their registration by a terminal unit, unlike other information offer system such as documents or complicated nationwide viewable web sites. Moreover, anyone can register the staff of their school. By using this system, the most important and useful effects (Reuse) include waste managements and loss in quantity (Reduce). Moreover, data can be obtained when recycling waste (Recycle). This type of system can be utilized as an important information system as an effective use of not only unnecessary goods in a university but also goods between students, and communities outside the university

    The geometric realizations of the decompositions of 3-orbifold fundamental groups

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    AbstractWe introduce a type of generalized orbifold called an “orbifold composition”. We study their topology and the extensions and deformations of the maps between them. As the main goal, we obtain the theorems which yield the geometric realizations of amalgamated free products and HNN extensions of 3-orbifold fundamental groups. They are extensions of results of Feustel (1972; 1973) and Feustel and Gregorac (1973)

    Electron Microscopic Investigation of Monoaminergic Terminals to α-Motoneurons in the Anterior Horn of the Cat Spinal Cord

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    In the anterior horn of the cat thoracic cord, networks of the monoaminergic fibers surrounding the alpha-motoneurons were investigated by fluorescent microscopy and submicroscopically. Monoaminergic terminals were recognized by the administration of 5-OHDA electron microscopically. These terminals could be classified morphologically into three types. The physiological significance of monoaminergic control of alpha-motoneurons was discussed. Type I of the labeled terminals did not show any typical synaptic specialization, such as aggregation of synaptic vesicles or thickening of the pre- and postsynaptic membranes. This type did not have synaptic contact with the alpha-motoneurons. Type II showed typical synaptic contact and asymmetrical synaptic type membranous thickening. A large number of small dense-cored vesicles were accumulated in the vicinity of the presynaptic membranes. Type III contained a large number of small and large dense-cored vesicles and a few flattened small vesicles. This type had synaptic contact with the presynaptic nerve ending in which a large number of agranular vesicles were contained. This study demonstrated that alpha-motoneurons in the anterior horn receive supraspinal monoaminergic control in three ways: modulator control through Type I, monosynaptic direct control through Type II, and inhibitory control through Type III.</p
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