646 research outputs found
Effects of Instantons on the YN Interaction
We investigate the symmetric and anti-symmetric spin-orbit forces (SLS and
ALS) of the effective N 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 N channel enhances N ALS,
and therefore that the cancellation between SLS and ALS in the N
channel becomes more complete. This may be one of the major reasons why the
single-particle spin-orbit force of in nuclei is weak.Comment: 3 pages, 2 figures, FewBody XV
The untangling theorem
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
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 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
The realizations of the amalgamated free products of 3-orbifold fundamental groups(Analysis of Discrete Groups II)
Development of an Unnecessary Goods Reuse Information Offer System For Creating a Recycling Society
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
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
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
- …