5,329 research outputs found
Extension of the Barut-Girardello Coherent State and Path Integral II
We have constructed the coherent state of , which is an extension of
the Barut-Girardello (BG) coherent state of , in our previous paper.
However there is a restriction that the eigenvalue of the Casimir operator is
natural number. In this paper we construct the coherent state in the analytic
representation to overcome this restriction. Next we show that the measure of
the BG coherent state is not the symplectic induced measure.Comment: latex, no figure, 14 page
Multi-Periodic Coherent States and the WKB-Exactness
We construct the path integral formula in terms of ``multi-periodic''
coherent state as an extension of the Nielsen-Rohrlich formula for spin. We
make an exact calculation of the formula and show that, when a parameter
corresponding to the magnitude of spin becomes large, the leading order term of
the expansion coincides with the exact result. We also give an explicit
correspondence between the trace formula in the multi-periodic coherent state
and the one in the ``generalized'' coherent state.Comment: 28 pages, late
Multi-Periodic Coherent States and the WKB-Exactness II ``Non-compact Case and Classical theories Revisited''
We show that the WKB approximation gives the exact result in the trace
formula of ``'', which is the non-compact counterpart of , in terms
of the ``multi-periodic'' coherent state. We revisit the symplectic 2-forms on
and and, especially, construct that on with the unitary
form. We also revisit the exact calculation of the classical patition functions
of them.Comment: LaTeX, 29 page
Coherent states, Path integral, and Semiclassical approximation
Using the generalized coherent states we argue that the path integral
formulae for and (in the discrete series) are WKB exact,if
the starting point is expressed as the trace of with
being given by a linear combination of generators. In our case,WKB
approximation is achieved by taking a large ``spin'' limit: . The result is obtained directly by knowing that the each coefficient
vanishes under the () expansion and is examined by another
method to be legitimated. We also point out that the discretized form of path
integral is indispensable, in other words, the continuum path integral
expression leads us to a wrong result. Therefore a great care must be taken
when some geometrical action would be adopted, even if it is so beautiful, as
the starting ingredient of path integral.Comment: latex 33 pages and 2 figures(uuencoded postscript file),
KYUSHU-HET-19 We have corrected the proof of the WKB-exactness in the section
Intergrowth and thermoelectric properties in the Bi-Ca-Co-O system
Single crystals of the Bi-Ca-Co-O system have been grown using the flux
method with cooling from 900\celsius and 950\celsius, respectively. The
single crystals are characterized by transmission electron microscopy and X-ray
diffraction. The misfit cobaltite
[CaBiCoO][CoO] single crystals with
quadruple (=4) rocksalt (RS) layer are achieved with cooling from
900\celsius. Such crystal exhibits room-temperature thermoelectric power
(TEP) of 180V/K, much larger than that in Sr-based misfit cobaltites with
quadruple RS layer. However, intergrowth of single crystals of quadruple
(=4) and triple (=3) RS-type layer-based misfit cobaltites is observed
with cooling from 950\celsius. Both of TEP and resistivity were obviously
enhanced by the intergrowth compared to
[CaBiCoO][CoO] single crystal,
while the power factor at room temperature remains unchanged.Comment: 8 pages, 7 figures. To be published in Journal of Crystal Growt
Animal Biotechnology Roles in Livestock Production
Currently, meat and milk productions are significantly increasing especially in Asia. The supply of these products is vital to people's health and well-being, whereas the efficiency of beef production appears to be still lower than other meat productions. Improvements in the quality and functionality of their livestock products, as well as their production efficiency, are required for further production. Animal biotechnologies have contributed to genetic improvement, genetic diversity maintenance of domestic animals, etc. Basic animal biotechnologies, such as artificial insemination and embryo transfer, have been well established and applied as powerful tools for genetic improvement of livestock. In the applications of artificial insemination techniques, the use of sexed semen has been now widely spread, and also efforts are also made in the development of the technology using a small amount of sperm. For embryo transfer, several types of vitrification technologies have been applied to improve pregnancy rates and contributed to the international/domestic supply of livestock embryos. Conventional animal biotechnologies, such as in vitro fertilization and intracellular sperm injection, have been applied to not only livestock production and also human-assisted reproductive medicine. For in-vitro production of embryos in domestic animals, currently, oocytes have been collected from medium or large follicles (3-6 mm or larger in diameter) of ovaries. Although the oocytes derived from small follicles (less than 3 mm in diameter) exist more on the surface of ovaries, the developmental competence of the oocytes has been known to be significantly lower than those from medium follicles. If we could improve the competence of oocytes derived from small follicles significantly, we may be able to increase the number of female gamete resources for in vitro embryo production. Also, the development of techniques for producing transgenic and cloned animals has greatly contributed to the creation of pharmaceuticals and organs for xenotransplantation. Recently, furthermore, genome editing technologies, such as combined use of CRISPR/Cas9 and PiggyBac, have been developed and have made it possible to correct specific parts of the genome and introduce mutations by homologous recombination. In this review, I would like to discuss the application and progress of the above biotechnologies, including our recent research results
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