Solar Models with Helioseismic Constraints and the Solar Neutrino Problem

Imposing a constraint of the sound-speed profile determined from helioseismology and updating the microphysics, we have revised our seismic solar model, constructed with the assumption of a homogeneous metal abundance distribution, and have shown that the theoretically expected neutrino fluxes are still significantly more than the observations. With the same sound-speed profile constraint, we also constructed solar models with low metal abundance in the core, and evaluated the neutrino fluxes of these models to see if nonstandard solar models with a low metal core can solve the solar neutrino problem. Some of these models are in agreement with the Homestake data, the Super-Kamiokande data, and the sound-speed profile simultaneously, but none of these satisfy both the neutrino flux data, including GALLEX and SAGE, and the helioseismically determined density profile.Comment: 12 pages, 17 figures, uses pasj00.cls. Accepted for publication in PAS

Tunneling rotation of methyl group and the spin-lattice relaxations of the proton NMR in acetamide and thioacetamide

Thesis--University of Tsukuba, D.Sc.(A), no. 347, 1986. 3. 2

Elevation of Ammonia Contents in the Cerebral Hemisphere under the Blood-Brain Barrier Opening

Elevation of ammonia contents was observed 1 hr following infusion of 4% ammonium acetate only in the cerebral hemisphere where reversible opening of the blood-brain barrier was induced by intracarotid injection of 0.1% deoxycholic acid. This finding suggests that ammonia may contribute to hepatic encephalopathy, when the permeability of the blood-brain barrier is altered

Bile Acid and Ammonia-Induced Brain Edema in Rats

Infusion of bile acid such as chenodeoxycholic acid or deoxycholic acid through the carotid artery of rats produced reversible and unilateral opening of the blood-brain barrier without any tissue damage. Intravenous drip infusion of ammonium acetate during the opening resulted in severe edema of the brain. The results suggest the importance of bile acid and ammonia for the pathogenesis of brain edema frequently observed in acute hepatic failure