Selective deposition of polystyrene nanoparticles in a nanoetchpit array on a silicon substrate

Nanometer-sized polystyrene particles were selectively deposited by interfacial tension in nanometer-sized etchpit arrays made on a silicon substrate.     

Search for coherent charged pion production in neutrino-carbon interactions

We report the result from a search for charged-current coherent pion production induced by muon neutrinos with a mean energy of 1.3 GeV. The data are collected with a fully active scintillator detector in the K2K long-baseline neutrino oscillation experiment. No evidence for coherent pion production is observed, and an upper limit of is set on the cross section ratio of coherent pion production to the total charged-current interaction at 90% confidence level. This is the first experimental limit for coherent charged pion production in the energy region of a few GeV.     

Skyrme solitons with vector mesons

We investigate the Skyrme type soliton with vector mesons (ρ, A₁ and ω), first in the massive Yang-Mills approach and then using the hidden local symmetry Lagrangian. It is demonstrated that the two schemes give identical results for the soliton properties. A comparison is made with alternative approaches in which the A₁ degrees of freedom is eliminated.     

Skyrmions and their interactions using the Atiyah-Manton construction

The Atiyah-Manton (AM) construction based on instantons is used to construct skyrmions. For baryon number one, an analytic form for the skyrmion is obtained that compares well with the exact solution. For baryon number two, we study skyrmion interactions and distortion as a function of relative distance and orientation. From this we project out a nucleon-nucleon interaction. We find the principal features of the nuclear force but still no intermediate-range attraction. We compare the AM construction with the product ansatz.     

Synthesis and protective effect of 1,3,5-triazine derivatives, leukotriene C4 antagonist, on HCl.ethanol-induced gastric lesions in rats.

2,4-Diamino-[E]-6-[2-(3-pyridyl)ethenyl]-1,3,5-triazine (3a), leukotriene C4 (LTC4) antagonist, was found to possess a protective effect on HCl.ethanol-induced gastric lesions. Analogues of 3a were synthesized and evaluated for the effect as well as antagonistic activity against LTC4-induced contraction. Seven compounds (3a-d, f-h) exhibited a potent protective effect on gastric lesions which was considered to be based on the antagonistic activity against LTC4. The structure-activity relationships of the derivatives (3a-k) are discussed.     

Pion fluctuation around the hedgehog solution in the chiral bag plus skyrmion hybrid model

The Roper excitation is studied in the chiral bag plus skyrmion hybrid model. The lagrangian is expanded around the classical solution in the hedgehog vibrational mode. In the adiabatic approximation we find a self consistent solution for the fluctuating system of quarks and pions up to the first order of the fluctuations. Only half of the excitation energy was found in the phase shift analysis. It is also discussed that the system is stable for all bag radii against the hedgehog vibration.     

piN and pipiN couplings of the Delta(1232) and its chiral partners

We investigate the interactions and chiral properties of the four spin-3/2 baryons N(-)(D13), N+(P13), Delta+(P33), and Delta(-)(D33) together with the nucleon. We construct the SU(2)R x SU(2)L invariant interactions between the spin-1/2 and spin-3/2 baryons with the aid of a new, specially developed spin and isospin projection technique for these baryon fields, where the chiral invariant interactions contain one- and two-pion couplings. We obtain simple relations for the coupling constants of the one- and two-pion spin-1/2-3/2 transitions terms. The relation for the one-pion interactions reasonably agrees with the experiments, which suggests that these spin-3/2 baryons are chiral partners.     

Synthesis of antisense oligodeoxyribonucleotide analogues by use of deoxyribonucleoside 3′-bis(1, 1, 1, 3,3,3-hexafluoro-2-propyl) phosphites as new key intermediates

The deoxyribonucleoside 3′-bis(1,1,1,3,3,3-hexafluoro-2-propyl) phosphite units ( 3 ) are used in the chemical synthesis of oligodeoxyribonucleotides on solid supports. The new phosphite units ( 3 ) were prepared easily by reaction of nucleosides and tris-(1,1,1,3,3,3-hexafluoro-2-propyl) phosphite ( 2 ). They are readily activated by N-methylimidazole under very mild conditions on a solid support. This operation involves a one step reaction, which is an advantage over both the phosphite and H-phosphonate approaches. The use of deoxyribonucleoside phosphite intermediates in the synthesis of antisense oligodeoxyribonucleotides is also described.