The Structure and Fate of Germinal Plasm in the Asiatic Fire-Bellied Frog, Bombina orientalis (Anura-Discoglossidae)

Lehman\u27s polychrome stain was used to follow the fate of germinal plasm in early development of Bombina orientalis embryos. Islets of germinal plasm approximately 6 um in diameter were observed in the vegetal pole region of the 2-cell embryo. By the 4-cell stage, some of these islets had coalesced to form larger ones so that two size classes of islets were present (approximately 7.5 and 19.5 um in diameter). As cleavage continued to the 16-cell stage, the islets were moved further up the cleavage furrow and were always observed to remain in close association with the cleavage membrane. The islets at this time had reached a diameter of approximately 32 um. In the 32-cell embryo, the cells that contained germinal plasm and that were also adjacent to the developing blastocoel, exhibited a protuberance of cytoplasm consisting of pigment, yolk and germinal plasm. At the mid-to late blastula stage, the germinal plasm was contained in a few cells located in the lower one-third of the embryo. The peripheral position of the germinal plasm was maintained in these cells. During early gastulation, the germinal plasm began to migrate from its peripheral location to a juxtanuclear position. Examination of neurula and early tail bud stages did not reveal any cells containing germinal plasm. The implication was that the germinal plasm may have been utilized previously to these stages. At the time of opercular closure (which is an equivalent stage to Shumway stage 25), there were approximately 61 primordial germ cells in the dorsal mesentery and genital ridges

Levels and Timing of Nitrogen Fertilizer Applications for Tall Fescue in Central Alabama

Tall fescue (Festuca arundinacea Schreb.), the most important cool season perennial pasture grass in the United States, is generally well adapted to the northern two-thirds of Alabama. Unfortunately, the most commonly grown tall fescue cultivar, Kentucky 31, is of northern origin and is dormant during the winter. To reduce this problem, AU Triumph was selected from Mediterranean germplasm. The Alabama Agricultural Experiment Station released this cultivar to growers in 1981. Compared to Kentucky 31, AU Triumph produces about 80 percent more forage during the winter and produces mature seed about 2 weeks earlier in the spring. Total annual forage production for the two cultivars is usually about the same

Levels and Timing of Nitrogen Fertilizer Applications for Tall Fescue in Central Alabama

Tall fescue (Festuca arundinacea Schreb.), the most important cool season perennial pasture grass in the United States, is generally well adapted to the northern two-thirds of Alabama. Unfortunately, the most commonly grown tall fescue cultivar, Kentucky 31, is of northern origin and is dormant during the winter. To reduce this problem, AU Triumph was selected from Mediterranean germplasm. The Alabama Agricultural Experiment Station released this cultivar to growers in 1981. Compared to Kentucky 31, AU Triumph produces about 80 percent more forage during the winter and produces mature seed about 2 weeks earlier in the spring. Total annual forage production for the two cultivars is usually about the same

CPAs And Electronic Survey Media

Gathering and utilizing data about customers and other stakeholders has become vital to maintaining competitiveness in today’s business world. With the ongoing expansion of the Internet, new methods for data collection are available. The success of utilizing new methods depends on the technological capabilities of the audience from whom data are sought.  One group of business professionals perceived to possess above average technological skills is practicing Certified Public Accountants (CPAs). A study was designed to measure the response rates of CPAs to different survey administration methods. This study compares one traditional survey method (regular mail) with newer methods for collecting survey data (e-mail and WWW form)

Electronic states of metallic and semiconducting carbon nanotubes with bond and site disorder

Disorder effects on the density of states in carbon nanotubes are analyzed by a tight binding model with Gaussian bond or site disorder. Metallic armchair and semiconducting zigzag nanotubes are investigated. In the strong disorder limit, the conduction and valence band states merge, and a finite density of states appears at the Fermi energy in both of metallic and semiconducting carbon nanotubes. The bond disorder gives rise to a huge density of states at the Fermi energy differently from that of the site disorder case. Consequences for experiments are discussed.Comment: Phys. Rev. B: Brief Reports (to be published). Related preprints can be found at http://www.etl.go.jp/~harigaya/NEW.htm

The multiple ionospheric probe Auroral ionospheric report

Multiple impedance and resonance probe payload for ionospheric property observation in Nike- Apache rocke

One-electron states and interband optical absorption in single-wall carbon nanotubes

Explicit expressions for the wave functions and dispersion equation for the band p - electrons in single-wall carbon nanotubes are obtained within the method of zero-range potentials. They are then used to investigate the absorption spectrum of polarized light caused by direct interband transitions in isolated nanotubes. It is shown that, at least, under the above approximations, the circular dichroism is absent in chiral nanotubes for the light wave propagating along the tube axis. The results obtained are compared with those calculated in a similar way for a graphite plane.Comment: 16 pages, 8 figures, 1 tabl