Two approaches have been pursued to construct bulk magnets by ordering spins of unpaired 2p-electrons of organic free radicals. One is an intermolecular approach based on the crystal design of stable radicals. The other consists of intramolecular alignment of spins in polyradicals having many unpaired electron. The two approaches progressed complementarily to establish unprecedented molecule-based magnets. The second approach by our research group developed polyradicals, polycarbenes and their supramolecular assemblies with metal ions into permanent magnets, thereby deepening the understanding of chemical bonds and opening a new horizon of developing new magnets with other functionality.
Borrelidin is a natural product possessing a variety of biological activities. Its total synthesis has been reported by several groups including those of Morken, Hanessian, Theodorakis and ourselves and two other synthetic studies toward the total synthesis have also been described by the groups of Haddad and Negishi. All these synthetic methods are reviewed herein.
By using the detection system of the near-horizontal cosmic-ray radiography originally developed for probing inner structure of volcanic mountains, a measurement was conducted to probe the inner structure and its time-dependent change of the blast furnace for iron-making. Precise determination (±5 cm) of the thickness of brick used for both base-plate and side-wall was made in 45 days; a crucial information to predict a life-time of the furnace. Also, the local density of iron-rich part was determined in ±0.2 g/cm2 in 45 days; static structure as well as time-dependent behavior can be monitored for the iron-rich part of the furnace during operation.
We have started electromagnetic (EM) monitoring of Taal volcano, Philippines. Taal is a basaltic-andesite volcano which has many eruption histories and is close to Metro Manila. On Taal, various geophysical and geochemical observations have been conducted by the government basis, but not the EM monitoring. A cooperative project for EM studies between PHIVOLCS and EMSEV/IUGG has been started. Measurements of total magnetic field (TMF), self-potential (SP), ground temperature and carbon dioxide degassing were made during the first survey in January 2005. Distinct anomalies in TMF and SP were found in the geothermal areas in Taal. Repeated survey in February detected changes in TMF up to a few tens of nT and enhancement of positive SP anomaly during the one and half-months period, when the surface geothermal activities were high. We believe that the combination of mechanical and electromagnetic measurements is uniquely effective in deciphering the volcanic activity.
Early Tithonian (Late Jurassic) ammonite Parapallasiceras cf. pseudocontiguum (Donze and Enay) was discovered in situ from the Kamihambara Formation of the Itoshiro Subgroup (Tetori Group) distributed in the Hida Belt, in Fukui Prefecture, northern Central Japan. It is a Perisphinctid characterized by polygyrate ribbing and can be compared to the said species originally described in Southeast France. The species occurs in the Lower Tithonian of the Submediterranean region. Therefore at least a part of the Itoshiro Subgroup can be dated Early Tithonian, judged by this ammonite.
Phase equilibrium relationships for the pelitic schists were examined by "pseudosection" method using the bulk rock composition of Sanbagawa pelitic schist in the garnet zone of central Shikoku, Japan. The obtained P-T pseudosections reproduce the observed sequence of mineral zones in the Sanbagawa pelitic schist: the chlorite, garnet and biotite zones with an increasing order of metamorphic grade. The effect of MnO content on the stability of garnet was examined on P-T pseudosections by changing the MnO content of the bulk rock composition from 0.0 to 0.2 wt%. It follows that the characteristic sequence of the mineral zones observed in the Sanbagawa pelitic schist owes to the higher pressure of metamorphism along with the MnO content.
Methylation of pairs of adenines at their N6 positions in GATC sites (GATC methylation) in archaeal genomic DNAs has been studied. Genomic DNAs in cells of three archaeal species were found as fully methylated, while those of four other archaeal species were free of such methylation. Consistently with this pattern of the presence or absence of GATC methylation, homologues of E. coli Dam methylase was found present or absent, but various other types of DNA methylases were not. A Dam homologue from Pyrococcus sp. OT3 was expressed and its expected function of methylating GATC was confirmed. By methylation of each adenine the DNA duplex was destabilized by 0.56 ± 0.10 Kcal/mol, and this effect was additive. For some archaea, transcription regulation of Dam methylase gene appears to be needed upon cell replication, and in regions upstream of three Dam methylase genes, nucleotide sequences close to TTTTCTTTGAAAA were present. This arrangement, five bases each at the ends, which are complementary to each other, sandwiching three T bases at the center, fits into a pattern the same as those recognized by dimers of transcription factors, feast/famine regulatory proteins (FFRPs).