Mechanism of texture and microstructure evolution during high temperature plane strain compression in AZ31B and AZ80 magnesium alloys with various initial textures

The effects of pre-existent textures on the evolution behaviors of microstructure and texture at high-temperature plane strain compression deformation of AZ31B magnesium alloy have been studied. Deformation is conducted at 723 K with a strain rate of 5.0 x 10(-2) s(-1), up to -1.3 in true strain. When non basal slip systems are the primary slip systems, {11 (2) over bar0}0> texture develops. In this case, repeated change in microstructure and texture which was found in the previous work appeared with increasing strain. Namely, replacement of {11 (2) over bar0}0> texture with 0>{11 (2) over bar0} texture and the reverse phenomenon occurs. While the {11 (2) over bar0}0> oriented grains are small and with wavy shaped grain boundaries, the {10 (1) over bar0}0> oriented grains are large and with rather straight grain boundaries. The mechanism of repeated change in microstructure and texture is discussed on the basis of preferential dynamic grain growth mechanism proposed by the authors.Web of Science83827226

Novel c.2216T > C (p.I739T) Mutation in Exon 13 and c.1481T > A (p.L494X) Mutation in Exon 8 of MUT Gene in a Female with Methylmalonic Acidemia

We report herein a 1.5-year-old girl with methylmalonic acidemia (MMA) in whom two missense mutations were found: a novel I739T mutation located in exon 13 and the L494X mutation in exon 8. The results of organic acid test showed a pronounced increase in methylmalonate excretion with increased methylcitrate and 3-OH-propionate excretion, leading to a diagnosis of MMA, and Vitamin B12 administration was started. Analysis of the mut gene confirmed a T-to-A substitution at nucleotide position 1481 in exon 8 and a T-to-C substitution at nucleotide position 2216 in exon 13, leading to the amino acid isoleucine at position 739 being changed to threonine, resulting in c.2216T > C (p.I739T). The patient has now been on high-dose oral administration of Vitamin B12 and carnitine therapy (900 mg of levocarnitine chloride) for 5 years without experiencing further attacks, and her cognitive and motor development is normal. Further tests on residual enzyme activity, as well as experience with more cases, may shed light on the relationship between gene mutations and phenotypes in MMA

Effect of Oxygen Impurities on Positronium Formation in Voids of Vanadium

To clarify the effect of oxygen impurities on positronium (Ps) formed in irradiation-induced voids, measurements of the angular correlation of two photon annihilation radiation (ACAR) have been done on vanadium samples doped with oxygen impurities and subsequently irradiated with fast neutrons of doses up to 5.5x10^cm^ at about 400℃ in the Japan Materials Testing Reactor (JMTR). It has been shown that slight contamination of voids with oxygen impurity atoms, presumably submonolayer adsorption on the void surface, causes Ps formation. On the other hand, the considerable contamination leads suppression of Ps formation. Energy loss process of Ps in voids is found to be also influenced by the surface contamination

Photosynthesis-irradiance relationship of phytoplankton and primary production in the vicinity of kuroshio warm core ring in spring

The light-saturated maximum value (P B max ) and initial slope (α) of the photosynthesisirradiance (P-E) curve were examined in a warm streamer, a cold streamer and a warm core ring off the Sanriku area in the subarctic western North Pacific Ocean during an ADEOS/OCTS Sanriku field campaign in early May 1997. Both P B max and α were within the ranges of temperate populations. A regional difference was apparent in P B max : populations in the warm streamer tended to show higher value ranging between 1.92 and 4.74 mgC (mgChl a) -1 h -1 than those in the cold streamer and the warm core ring (1.35-2.87 mgC (mgChl a) -1 h -1 ). A depth variation was also observed in α in both the warm streamer and the warm core ring: shallow populations tended to have lower α than deep populations. The depth variations in both P B max and α resulted in a lower light intensity of the light saturation in a deeper population than that of a shallower one. These depthrelated variations in the P-E parameters were likely a manifestation of "shade-adaptation" of photosynthesis. Photoinhibition was not observed over in situ surface light intensity varying below ca 1600 µmol photon m -2 s -1 . Water-column primary productivity was biooptically estimated to be 233 to 949 mgC m -2 d -1 using vertical distributions of the P-E parameters, chlorophyll a, phytoplankton light absorption and underwater irradiance. Applicability of surface data sets for estimation of water-column productivity is discussed

Ⅲ.Chemistry

金沢大学大学院自然科学研究科 環境科学Editor : Tazaki, Kazue |田崎, 和

The expression of Ca2+/calmodulin-dependent protein kinase I in rat retina is regulated by light stimulation

AbstractCa2+/calmodulin-dependent protein kinase I (CaM-kinase I) in rat retina was analyzed by immunohistochemical analysis, Western blot analysis and kinase activity assay. Western blot analysis revealed two immunoreactive bands similar to those detected in the brain. Developmental studies revealed that CaM-kinase I expression increased in accordance with postnatal development. Expression of CaM-kinase I in the retinas of rats raised in the complete darkness markedly decreased. CaM-kinase I activity assay supported these findings. Synapsin I was shown to be a possible intrinsic substrate of CaM-kinase I in rat retina. These results elucidated that CaM-kinase I is expressed in the retina and may play an important role in the retinal functions and that the expression of CaM-kinase I is regulated by light stimulation