Equivalence between Schwinger and Dirac schemes of quantization

This paper introduces the modified version of Schwinger's quantization method, in which the information on constraints and the choice of gauge conditions are included implicitly in the choice of variations used in quantization scheme. A proof of equivalence between Schwinger- and Dirac-methods for constraint systems is given.Comment: 12pages, No figures, Latex, The proof is improved and one reference is adde

Peacemaking: Our Essential Work in the Last Days

This address was given at the J. Reuben Clark Law Society Conference at Pepperdine University in Malibu, California, on February 16, 2007

Non-LTE Monte Carlo Radiative Transfer: II. Non-Isothermal Solutions for Viscous Keplerian Disks

We discuss the basic hydrodynamics that determines the density structure of the disks around hot stars. Observational evidence supports the idea that these disks are Keplerian (rotationally supported) gaseous disks. A popular scenario in the literature, which naturally leads to the formation of Keplerian disks, is the viscous decretion model. According to this scenario, the disks are hydrostatically supported in the vertical direction, while the radial structure is governed by the viscous transport. This suggests that the temperature is one primary factor that governs the disk density structure. In a previous study we demonstrated, using 3-D NLTE Monte Carlo simulations, that viscous keplerian disks can be highly non-isothermal. In this paper we build upon our previous work and solve the full problem of the steady-state non-isothermal viscous diffusion and vertical hydrostatic equilibrium. We find that the self-consistent solution departs significantly from the analytic isothermal density, with potentially large effects on the emergent spectrum. This implies that non-isothermal disk models must be used for a detailed modeling of Be star disks.Comment: 22 pages, 9 figures, Ap

Semiconductor-enriched single wall carbon nanotube networks applied to field effect transistors

Substantial progress on field effect transistors "FETs" consisting of semiconducting single wall carbon nanotubes "s-SWNTs" without detectable traces of metallic nanotubes and impurities is reported. Nearly perfect removal of metallic nanotubes is confirmed by optical absorption, Raman measurements, and electrical measurements. This outstanding result was made possible in particular by ultracentrifugation (150 000 g) of solutions prepared from SWNT powders using polyfluorene as an extracting agent in toluene. Such s-SWNTs processable solutions were applied to realize FET, embodying randomly or preferentially oriented nanotube networks prepared by spin coating or dielectrophoresis. Devices exhibit stable p-type semiconductor behavior in air with very promising characteristics. The on-off current ratio is 10^5, the on-current level is around 10 $\mu$A, and the estimated hole mobility is larger than 2 cm2 / V s

Magnetization Plateau of an S=1 Frustrated Spin Ladder

We study the magnetization plateau at 1/4 of the saturation magnetization of the S=1 antiferromagnetic spin ladder both analytically and numerically, with the aim of explaining recent experimental results on BIP-TENO by Goto et al. We propose two mechanisms for the plateau formation and clarify the plateau phase diagram on the plane of the coupling constants between spins

Exogenously added naphthols induce three glucosyltransferases, and are accumulated as glucosides in tobacco cells

Plants detoxify and accumulate several compounds as glucosides. In this work, detoxification of the exogenously added harmful compound naphthol in tobacco cells (Nicotiana tabacum L. Bright Yellow) was studied. When 250 μM of 1-naphthol or 2-naphthol was added to the tobacco cells, most of the naphthol was accumulated in the cell as glucosides and in further modified forms. The glucosylation activities against naphthols were increased in proportion to the concentration of naphthols in the culture medium. Addition of 1 mM naphthols caused cell death. Three glucosyltransferase genes, namely NtGT1a, NtGT1b and NtGT3 were isolated and characterized. The recombinant enzymes encoded by these genes showed glucosylation activity against naphthols and other phenolic compounds. It was also shown that these genes were induced following the addition of naphthols to the tobacco cells. These results suggest that naphthols are metabolized by glucosyltransferases whose production is inducible by naphthol itself.ArticlePlant Science. 164(2):231-240 (2003)journal articl