All issues
Volume 83, Issue 2
Displaying 1-3 of 3 articles from this issue
- |<
- <
- 1
- >
- >|
-
Atsuto SUZUKI2007 Volume 83 Issue 2 Pages 27-38
Published: 2007
Released on J-STAGE: March 15, 2007
JOURNAL FREE ACCESSKamLAND measured the νe's flux from distant nuclear reactors, and found fewer events than expected from standard assumptions about νe propagation at the 99.998% confidence level (C.L.). The observed energy spectrum disagrees with the expected spectral shape at 99.6% C.L., and prefers the distortion from neutrino oscillation effects. A two-flavor oscillation analysis of the data from KamLAND and solar neutrino experiments with CPT invariance, yields Δ m2 = 7.9 +0.6-0.5 × 10-5 eV2 and tan2 θ = 0.40+0.10-0.07. All solutions to the solar neutrino problem except for the large mixing angle (LMA) region are excluded. KamLAND succeeded in detecting geoneutrinos produced by the decays of 238U and 232Th within the Earth. The total observed number of 4.5 to 54.2, assuming a Th/U mass concentration ratio of 3.9 is consistent with 19 predicted by geophysical models. This detection allows better estimation of the abundances and distributions of radioactive elements in the Earth, and of the Earth's overall heat budget.
(Communicated by Masatoshi KOSHIBA, M. J. A.)View full abstractDownload PDF (1574K) -
Noboru MIZUSHIMA2007 Volume 83 Issue 2 Pages 39-46
Published: 2007
Released on J-STAGE: March 15, 2007
JOURNAL FREE ACCESSAutophagy is in principle a non-selective degradation system within cells, which is conserved in all eukaryotic cells. Autophagy is usually suppressed at low levels but can be upregulated during periods of nutrient starvation, which facilitates cell survival. In addition to this fundamental role, basal autophagy was recently revealed to be important for constitutive turnover of intracellular proteins and organelles. Autophagy has been considered to be involved also in presentation of endogenous antigens, degradation of invasive bacteria, tumor suppression, cell death and development. This review will discuss the biological significance of autophagy, particularly focusing on its implications in protein metabolism in mammals.
(Communicated by Takao SEKIYA, M.J.A.)View full abstractDownload PDF (534K) -
Masanori OTSUKA2007 Volume 83 Issue 2 Pages 47-64
Published: 2007
Released on J-STAGE: March 15, 2007
JOURNAL FREE ACCESSPart I describes important contributions made by some Japanese pioneers in the field of neurotransmitters: (their achievements in parentheses) J. Takamine (isolation and crystallization of adrenaline); K. Shimidzu (early hint for acetylcholine as a neurotransmitter); F. Kanematsu (donation of the Kanematsu Memorial Institute in Sydney); T. Hayashi (discovery of the excitatory action of glutamate and the inhibitory action of GABA); and I. Sano (discovery of a high concentration of dopamine in striatum, its reduction in a patient with Parkinson's disease and the treatment with DOPA). In Part II, I present some of my reflections on my research on neurotransmitters. The work of my colleagues and myself has made some significant contributions to the establishment of neurotransmitter roles played by GABA and substance P, the first amino acid and the first peptide neurotransmitters, respectively. By the early 1960s, 3 substances, i.e., acetylcholine, noradrenaline, and adrenaline, had been established as neurotransmitters. Now the number of neurotransmitters is believed to be as many as 50 or even more mainly due to the inclusion of several amino acids and a large number of peptide transmitters.
(Contributed by Masanori OTSUKA, M.J.A.)View full abstractDownload PDF (1350K)
- |<
- <
- 1
- >
- >|