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We analyzed data from 28 long-term experimental monitoring plots installed in Japanese cedar (Cryptomeria japonica D. Don) plantations in northeastern Japan to examine how site productivity and thinning practices relate to culmination in stand growth. Site productivity and thinning practices in the plots were evaluated by site index (dominant tree height at 40-years old) and by cumulative thinning rate (cumulative thinning volume divided by cumulative gross production during the entire period of measurement). Culmination of stand growth was evaluated by culmination age of the mean annual increment (MAI) and its maximum value (Max MAI). Max MAI for the mean annual gross increment (MAIgross) and mean annual net increment (MAInet) increased with increasing site index, but did not change with cumulative thinning rate. Culmination age for MAIgross decreased with increasing site index, but did not change with cumulative thinning rate. Culmination age for MAInet decreased with increasing site index. Additionally, culmination age for MAInet increased with increasing cumulative thinning rate in sites with a high site index ([19.3 m) but not in those with a low site index (\19.3 m). These results indicate that thinning extends the culmination age without changing Max MAInet under high site productivity. Therefore, thinning increases total net yield in sites with high productivity based on a long-term perspective.

Innovative method acceptable for production of Iridium (Ir) and Ruthenium (Ru) metal fibers with high melting point and poor workability is developed using an alloy-micro-pulling-down (A-μ-PD) method and ceramic crucibles with sufficient mechanical and thermal shock resistance. As-grown (as-solidified) Ir and Ru fibers are approximately 1 mm in diameter and their lengths exceed 15 and 0.3 m, respectively. Both Ir and Ru fibers are composed of number of elongated grains oriented along a growth direction, which is attributable to the unidirectional solidification. The flexibility and oxidation resistance of the Ir fiber grown by the A-μ-PD method is considerably improved as compared to a commercial Ir wire made by wiredrawing process.

A seventeen-membered heterocycle (VI), made from anisaldehyde by an eight-step synthesis, was shown to be identical with the product of dehydrogenation of dideoxy-NO-dimethyl-lythranidine. Lythranidine, a novel alkaloid from L ythrum anceps Makino, was thus assigned the structure (XV).RECENTLY we isolated three novel alkaloids, lythranine, lythranidine, and lythramine, from Lythrzm aptceps Makino, a herb grown in Japan, and clarified their relationship with each other.3 Subsequently, we suggested structure (I) for 0-methyl-lythranidine, on the basis of several reactions and spectroscopic data.l We now present more positive evidence supporting this assignment.As previously described,l NO-dimethyl-ly thranidine (11) was treated with phosphoryl chloride in pyridine, and the crude product was catalytically hydrogenated to give a monochloro-( 111) and a dichloro-derivative (IV). Each of these on reductive dehalogenation gave dideoxy-NO-dimethyl-lythranidine (V) .Compound (V) was dehydrogenated over palladium black at 300" under reduced pressure to give an oil, which was chromatographed on a silica gel column to yield a crystalline product, m.p. 152-153". Analysis and spectroscopic data suggested structure (VI) for this material.The same compound (VI) was independently synthesised as follows. Anisaldehyde (VII) was treated with iodine monochloride in acetic acid * to give 3-iodoanisaldehyde (VIII)? which gave compound (IX) when subjected to Ullmann's reaction in the presence of copper powder (yield 45%). The product (IX) was condensed with malonic acid in pyridine in the presence of piperidine ' to yield an unsaturated casboxylic acid, which 1

Microcystins are a group of cyclic heptapeptide hepatotoxins produced by the cyanobacteria. Two microcystin-degrading strains of bacteria (MG and MG ) were isolated from a monoxenic culture of Monas guttula preying on Microcystis viridis. Both strains were related to Sphingopyxis and Novosphingobium groups based on phylogenetic analysis of S rDNA. Degradation of microcystin by these strains was tested under the following conditions: temperature from to , pH from . to . , three diff erent microcystin analogs and initial microcystin concentrations from to μg l -. The rate of microcystin RR degradation by strain MG signifi cantly increased at , whereas the eff ect of temperature on the degradation rate by strain MG was small. Both strains could degrade microcystin under alkaline pH. Both strains could degrade microcystin RR, YR and LR. The degradation rate of microcystin RR by the two strains was faster than the degradation rates of microcystin YR and LR. Both strains could degrade microcystin LR at all initial concentrations.