Chiaki Okada

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KamLAND has measured the flux of nu;(e)'s from distant nuclear reactors. We find fewer nu;(e) events than expected from standard assumptions about nu;(e) propagation at the 99.95% C.L. In a 162 ton.yr exposure the ratio of the observed inverse beta-decay events to the expected number without nu;(e) disappearance is 0.611+/-0.085(stat)+/-0.041(syst) for(More)
The persistence of deficits found by solar neutrino experiments and the impressive results from Super-Kamiokande on atmospheric neutrinos are the impetus for new, higher sensitivity measurements of neutrino oscillations. The KamLAND experiment will exploit the old Kamiokande underground site and the presence of large nuclear power reactors to obtain two(More)
A search has been made for neutrinos from the hep reaction in the Sun and from the diffuse supernova neutrino background (DSNB) using data collected during the first operational phase of the Sudbury Neutrino Observatory, with an exposure of 0.65 ktons yr. For the hep neutrino search, two events are observed in the effective electron energy range of 14:3 MeV(More)
Upper limits on the e flux at the Sudbury Neutrino Observatory have been set based on the e charged-current reaction on deuterium. The reaction produces a positron and two neutrons in coincidence. This distinctive signature allows a search with very low background for e 's from the Sun and other potential sources. Both differential and integral limits on(More)
A search has been made for sinusoidal periodic variations in the 8 B solar neutrino flux using data collected by the Sudbury Neutrino Observatory over a 4-year time interval. The variation at a period of 1 yr is consistent with modulation of the 8 B neutrino flux by the Earth's orbital eccentricity. No significant sinusoidal periodicities are found with(More)
Calothrixin B, whose structure consists of a pentacyclic indolo[3,2-j]phenanthridine framework, was originally isolated as a secondary metabolite from Calothrix cyanobacteria and was found to exhibit potent antiproliferative activity. In this study, treatment with 100 μM of calothrixin B did not inhibit the proliferation of HL-60 promyelocytic leukemia(More)
Results are reported on the measurement of the atmospheric neutrino-induced muon flux at a depth of 2 kilometers below the Earth's surface from 1229 days of operation of the Sudbury Neutrino Observatory (SNO). By measuring the flux of through-going muons as a function of zenith angle, the SNO experiment can distinguish between the oscillated and(More)
Data from the Sudbury Neutrino Observatory have been used to constrain the lifetime for nucleon decay to "invisible" modes, such as n-->3nu. The analysis was based on a search for gamma rays from the deexcitation of the residual nucleus that would result from the disappearance of either a proton or neutron from 16O. A limit of tau(inv)>2 x 10(29) yr is(More)
Lipid A (also known as endotoxin) is the hydrophobic portion of lipopolysaccharides. It is an essential membrane component required for the viability of gram-negative bacteria. The enzymes involved in its biosynthesis are attractive targets for the development of novel antibiotics. LpxH catalyzes the fourth step of the lipid A biosynthesis pathway and(More)
The Sudbury Neutrino Observatory has precisely determined the total active (nu(x)) 8B solar neutrino flux without assumptions about the energy dependence of the nu(e) survival probability. The measurements were made with dissolved NaCl in heavy water to enhance the sensitivity and signature for neutral-current interactions. The flux is found to be 5.21 +/-(More)