Gluonic excitation of the three-quark system in SU(3) lattice QCD

We present the first study of the gluonic excitation in the three-quark (3Q) system in SU(3) lattice QCD with beta=5.8 and 16(3) x 32 at the quenched level. For the spatially fixed 3Q system, we measure the gluonic excited-state potential, which is responsible for the properties of hybrid baryons. The lowest gluonic-excitation energy in the 3Q system is found to be about 1 GeV in the hadronic scale. This large gluonic-excitation energy is expected to bring about the success of the simple quark model without gluonic modes.     

Synthesis and evaluation of 6-nitro-7-(1-piperazino)quinazolines: dual-acting compounds with inhibitory activities toward both tumor necrosis factor-alpha (TNF-alpha) production and T cell proliferation

We investigated the chemical modifications of the nitroquinazoline derivative (1) through the replacement of the NH group at the C(4)-position with several N-alkyl groups to increase the lipophilicity at the C(4)-position. Among them, we found that the N-methyl analogue (5a) showed a 2-fold loss in the inhibitory activity toward tumor necrosis factor-alpha (TNF-alpha) production in vitro as compared with the NH analogue (1); however, 5a exhibited an oral inhibitory activity on TNF-alpha production with an ED50 value of 26 mg/kg, whereas 1 did not. Moreover, the oral bioavailability of 5a was higher than that of 1 (1, F=1%; 5a, F=21%), and the calculated ClogP value for 5a was higher than that for 1. These results suggest that the improved lipophilicity of 5a compared with that of 1 reflects its greater inhibitory activity on TNF-alpha production in vivo as well as oral bioavailability.     

Optical properties and origin of infrared light scattering centers in undoped semi-insulating GaAs crystals

The wavelength dependence and polarization characteristics of the infrared light scattered from an undoped GaAs crystal were investigated in the 90° angle infrared light scattering configuration. The scattering is Rayleigh scattering from scatterers which are always associated with the dislocations, and they are classified into three types,S, L _A , andL _G scatterers, according to their polarization characteristics. TheS, L _A , andL _G -scatterers are thought to be small As clusters, large As precipitates and large Ga precipitates, respectively.     

Total curvatures of Kaehler manifolds in complex projective spaces

Teufel showed that total absolute curvature of a submanifold in a sphere or a hyperbolic space equals to the mean value of the number of critical points of level functions. This is an extension of the classical work of Chern and Lashof. In this paper we shall prove a similar result holds for the total absolute curvature of Kaehler manifold in a complex projective space. We shall also express the total curvature by the Euler numbers.The present research was supported by Grant in Aid for Scientific Research No. 5754005.     

Synthesis of a novel tripodand having 3-hydroxy-2-naphthoeic amide groups and its anion recognition ability

A novel tripodand having 3-hydroxy-2-naphthoeic amide groups was prepared by the reaction of 1,3,5-tris(aminomethyl)-2,4,6-trimethylbenzene with 3-allyloxy-2-naphthoeic acid chloride followed by thermal Claisen rearrangement. This tripodand can exhibit the anion binding ability in chloroform solution. In particular, it can bind with acetate, dihydrogen phosphate, and fluoride ions to form 1:1 complexes.     

Direct electron transfer with glucose oxidase immobilized in an electropolymerized poly( N-methylpyrrole) film on a gold microelectrode

Direct electron transfer between active glucose oxidase (GOD) and a gold electrode was obtained when GOD was immobilized in poly(N-methylpyrrole) electrochemically prepared on the gold electrode. When electropolymerization was accomplished at 50 °C, after glucose addition, the cyclic voltammograms showed an increased oxidation peak at ca. ?0.45 V vs. Ag/AgCl. This potential corresponds to the oxidation potential for FADH₂. Although the GOD becomes much less selective, a glucose-dependent current response is obtained.     

An N-protection free ligation of the peptide thioester and the peptide with an N-alkoxy- or N-aryloxyamino group at its N-terminus

Peptides with an N-alkoxy or N-aryloxy amino acid at their N-terminus were synthesized and successfully ligated with a peptide thioester by silver ion activation under a slightly acidic condition without requiring protection of the side chain amino groups. The N-methoxy group was easily cleaved by the SmI₂ reduction in CH₃OH aq. to obtain the desired peptide with a native peptide bond. This method was successfully applied to the synthesis of the human atrial natriuretic peptide showing the efficiency of the novel ligation.