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The 15N natural abundance in Pinus densiflora Sieb. et Zucco that had been inoculated and not inoculated with ectomycorrhizal fungi (Suillus granulatus (L.:Fr.) O. Kuntze) was compared. The inoculated pine needles showed a lower δ15N value, while the uninoculated ones showed a higher δ15N value. Higher δ15N values in the mycelial mat of the ectomycorrhizal fungi compared to those of the inoculated pine needles were also observed. These facts indicate that nitrogen isotope fractionation occurred during the nitrogen transport from mycorrhizal fungi to the host plants.

Formability on cylindrical deep drawing and mechanical properties at relatively low temperature was investigated for a commercially rolled AZ31 magnesium. A small punch radius, which ratio to thickness was 2.5, was adoped intentionally. At room temperature, brittle fracture occurred near the flat portion of punch shoulder like as blanking. The ratio of drawing rate to punch diameter was from 5 to 200 mm/min, The drawing ratio of 1.67 was obtained at 383 K, and limiting drawing ratio of 2.2 was obtained at 453 K.

We have used first principle molecular dynamics to calculate lattice constants of the Mg 7 Li 1 alloy. The molecular dynamics enables us to optimize the crystal structure. The present calculations are based on the ab initio pseudopotential and the supercell approach. Two supercells of the Mg 7 Li 1 alloy are made up to discuss the stability of structure. We have also calculated bulk modulus of the Mg 7 Li 1 alloy.

BaTiO3 (BT) was synthesized by the solid state reaction of an almost equimolar mixture of BaCO3 and TiO2 in various atmospheres. The rate of reaction decreased as the CO2 partial pressure increased. There observed no Ba2TiO4 irrespective of the CO2 partial pressure in the whole temperature range studied. The morphology of BT powder calcined at 1035°C in air was spherical. However, it was angular and the particle growth was inhibited when calcined at 1035°C in the atmosphere with above 30vol% of CO2 partial pressure. Furthermore, the amount of the remained BaCO3 during the solid state reaction for angular BT was larger than that for spherical one from the X-ray diffraction analysis. It was found that BaCO3, of which decomposition was suppressed by the high CO2 partial pressure, had a considerable influence on the reaction rate, morphology of the particle, and the particle growth in the solid state synthesis of BT.

A new superplastic blow forming procedure for 7475 aluminum alloy sheets to provide the optimum distribution of thickness to a slender pan. The procedure adopts a preliminarily machined blank with different thickness locally before a superplastic forming (SPF). The figure and thickness for machining is calculated by a numerical analysis method developed for the pan to be formed with the optimum shape, size and thickness. This procedure also contains a friction between a sheet and a die, and work hardening of a blank material during SPF. It feeds the optimum pressurization schedule to the preliminarily machined blank to be formed with the maximum strain rate. A SPF of 7475 aluminum alloy sheets machined preliminarily to be formed a rectangular pan, in the ratio of the bottom to wall thickness is 2:1, according to the numerically calculated pressurizing schedule. The distribution of thickness in the formed pan was coincident with that of expected one.

The natural abundance of 13C and 15N was measured in basidiocarps of at least 115 species in 88 genera of ectomycorrhizal, wood-decomposing and litter-decomposing fungi from Japan and Malaysia. The natural abundance of 13C and 15N was also measured in leaves, litter, soil and wood from three different sites. 15N and 13C were enriched in ectomycorrhizal and wood-decomposing fungi, respectively, relative to their substrates. Ectomycorrhizal and wood-decomposing fungi could be distinguished on the basis of their δ13C and δ15N signatures. Although there was high variability in the isotopic composition of fungi, the following isotope- enrichment factors (e, mean±SD) of the fungi relative to substrates were observed: e ectomycorrhizal fungi/litter = 6.1±0.4‰15N e ectomycorrhizal fungi/wood = 1.4±0.8‰13C e wood-decomposing fungi/wood = −0.6±0.7‰15N e wood-decomposing fungi/wood = 3.5±0.9‰13C The basis of isotope fractionation in C metabolism from wood to wood-decomposing fungus is discussed.

The effect of temperature and grain size on superplastic flow was investigated using a relatively coarse-grained (∼20 μm) Mg–Al–Zn alloy for the inclusive understanding of the dominant diffusion process. Tensile tests revealed that the strain rate was inversely proportional to the square of the grain size and to the second power of stress. The activation energy was close to that for grain boundary diffusion at 523–573 K, and was close to that for lattice diffusion at 598–673 K. From the analysis of the stress exponent, the grain size exponent and activation energy, it was suggested that the dominant diffusion process was influenced by temperature and grain size. It was demonstrated that the notion of effective diffusivity explained the experimental results.

Recently, there is a high interest in using light-weight metallic foams (e.g., Al and Mg) for automotive, railway and aerospace applications where weight reduction and improvement in comfort are needed. Metallic foams also have a potential for absorbing impact energy during the crashing of a vehicle either against another vehicle or a pedestrian. In this study, enhancement of absorption energy in a closed-cell structure has been performed by an increase in the aspect ratio of cell-wall thickness against the cell-edge length with the reduction of cell size. The absorbed energy in a modified foam is estimated comparing with that in a conventional ALPORAS with the same relative density.

The effect of rare-earth elements, La, Sm, Dy, Ho and Er, on the microstructure in BaTiO3(BT)–MgO–rare-earth oxide based system was studied. Larger amount of MgO was required to suppress the grain growth for the larger ionic radius rare-earth ion (La, Sm)-doped samples than for the smaller ion (Dy, Ho, Er)-doped samples. Also, substitution modes of rare-earth elements and Mg in BT lattice were investigated. The solubility of rare-earth ions in BT lattice and the substitution ratio of rare-earth ions into Ba-site decreased as ionic radius decreases. This suggests that the formation of core-shell structures in BT–MgO–rare-earth oxide based system is dependent on the substitution ratio of rare-earth ions into Ba-site.

The numerical analysis on superplastic forming under plane strain was put in operation. This analytical method is able to account for the strain hardening with regard to strain rate of formed material. The strain rates of each element laid out on the formed material are determined by the combination of stress and strain which are provided by the theoretical equations and stress-strain curve on the tensile test under some strain rates. The experiment was carried out with the condition calculated by the analytical method on the corrugated die for 7475 Al-alloy. The deformation process and variation of thickness on the rectangular pan formed by optimum condition was good agreement with the result predicted by the calculation. By using this analytical method, superplastic forming of the rectangular pan which was controlled the thickness variation to 1: 2 on wall and bottom was planed. The thickness of blank sheet was machined locally according to the design by analysis. It was formed to the rectangular pan successfully. and the formed pan had the thickness distribution which was intended on the forming plan.

A 7475 aluminum alloy processed by powder metallurgically (P/M7475) has shown superplastic elongation more than 1000 % at a temperature of 788 K. The maximum elongation of P/M 7475 was recorded near a strain rate of 1x10 -1 s -1 , which is 3 orders magnitude faster than that of ingot metallurgically processed 7475 (I/M7475). This excellent superplastic performance at a higher strain rate is owing to a fine grain size of about 1μm developed by dynamic recrystallization at an early stage of superplastic flow. Morphology of grain boundary sliding with straining was inspected by the scanning electron microscopy. The contribution of grain boundary sliding was found to be low at an early stage of deformation, but was increasing with deformation. It was found that this trend was corresponding to an increase of misorientation angle by dynamic recrystallization with straining.

Low temperature superplastic behavior of a magnesium alloy, ZK60, was investigated at about half the absolute melting point. The grains were equiaxed with an average size of 6.5 μm. The tensile tests revealed that the material exhibited low temperature superplasticity (LTSP) with elongation-to-failure of over 400%. Microstructural observations suggested that grain boundary sliding (GBS) made a substantial contribution to the total strain. The stress exponent, grain size exponent and activation energy for superplastic flow were also characterized. The strain rate was inversely proportional to the cube of the grain size and to the second power of stress. The activation energy was close to that for grain boundary diffusion in magnesium. It is suggested that the deformation mechanism for LTSP is GBS accommodated by dislocation movement controlled by grain boundary diffusion.

Capsule Stable-isotope analysis indicated that terrestrial dipteran insects were the main food at a site in northern Japan.

For the design of the multilayer ceramic capacitors (MLCs) with core-shell structure, the solubility modes of La–Mg and La–Al into BaTiO 3 were clarified as a function of composition based on the lattice parameters' change. The lattice parameter was determined based on a cubic system at a higher temperature than the Curie temperature in order to avoid the crystal structure change. On the BaTiO 3 –La 2 O 3 –MgO system, there were three substitution modes. In the region where x was small on the (Ba 1− x La x )(Ti 1− x /2 Mg x /2 )O 3 , Mg ions preferentially dissolved into B site of BaTiO 3 , but in the region where x was large, both La and Mg ions dissolved into A and B site, respectively. On the other hand, on the BaTiO 3 –La 2 O 3 –Al 2 O 3 system, La and Al ions partially replaced Ba and Ti ions, respectively, according to pre-determined replacement formula (Ba 1− x La x )(Ti 1− x Al x )O 3 . The solubility range of La into BaTiO 3 was wider than that of Dy or Ho which make the core-shell structure. So, the dielectric materials composed of BaTiO 3 containing La are not fitted to form the core-shell structure. Therefore, considering ionic radius of rare earth element, BaTiO 3 containing rare earth elements whose ionic radii are much smaller than that of Ba is fitted to form the core-shell structure.

Incubation experiments using filtered waters from Lake Kasumigaura were conducted to examine bacterial contribution to a dissolved organic carbon (DOC) pool. Bacterial abundance, bacterial production, concentrations of DOC, total dissolved amino acids (TDAA), and total dissolved neutral sugars (TDNS) were monitored during the experiments. Bacterial production during the first few days was very high (20 to 35 μg C liter −1 day −1 ), accounting for 40 to 70% of primary production. The total bacterial production accounted for 34 to 55% of the DOC loss during the experiment, indicating high bacterial activities in Lake Kasumigaura. The DOC degradation was only 12 to 15%, whereas the degradation of TDAA and TDNS ranged from 30 to 50%, suggesting the preferential usage of TDAA and TDNS. The contribution of bacterially derived carbon to a DOC pool in Lake Kasumigaura was estimated using d -amino acids as bacterial biomarkers and accounted for 30 to 50% of the lake DOC. These values were much higher than those estimated for the open ocean (20 to 30%). The ratio of bacterially derived carbon to bulk carbon increased slightly with time, suggesting that the bacterially derived carbon is more resistant to microbial degradation than bulk carbon. This is the first study to estimate the bacterial contribution to a DOC pool in freshwater environments. These results indicate that bacteria play even more important roles in carbon cycles in freshwater environments than in open oceans and also suggests that recent increases in recalcitrant DOC in various lakes could be attributed to bacterially derived carbon. The potential differences in bacterial contributions to dissolved organic matter (DOM) between freshwater and marine environments are discussed.

There are conflicting reports regarding the occurrence of cardiovascular events after a major earthquake. To understand the impact of the Great East Japan Earthquake on cardiovascular events, we retrospectively examined the clinical records prepared by emergency room physicians between 2009 and 2011 (n = 66,244), and compared the occurrence of these events between 2011 and 2009, and 2011 and 2010. There was a significant increase in the number of patients with cardiovascular events during the 3 week period after the earthquake in 2011 (n = 106) compared with that during the same period in 2009 (n = 72) or 2010 (n = 65) (P = 0.002). The number of patients with acute coronary syndrome or congestive heart failure in March 2011 was significantly increased compared with 2009 or 2010, however, there were no significant increases in 2011 in other cardiovascular events including stroke, aortic dissection, pulmonary thromboembolism, or out-of-hospital cardiac arrest compared with 2009 or 2010. These findings suggest that the incidence of cardiovascular events may have been heterogeneous after the disaster.

Euphorbia tirucalli is a potential source of commercially important chemicals such as sterols. Here we report the first successful plant regeneration from internode explants of E. tirucalli. Adventitious buds were efficiently induced on LS medium supplemented with 0.02 mg l-1 thidiazuron. On average of four experiments, 17.3 adventitious buds were induced from 12 explants on this medium. The adventitious buds grew into shoots during subsequent cultures on a hormone-free LS medium. For rooting treatment, we cultured these shoots on the LS medium containing 0.02 mg l-1 naphthalenacetic acid, followed by on the half-strength LS medium without vitamins, and were successful to obtain whole plantlets.

Temporal changes in benthic food web structure were analyzed in an artificial tidal flat in inner Tokyo Bay, Japan, using carbon and nitrogen stable isotope ratios (δ 13 C and δ 15 N). Microphytobenthos were the most important food sources of macrozoobenthos, due to high microphytobenthic biomass on the tidal flat, while phytoplankton in canal water (canal POM PP ), terrestrial materials from urban surface runoff (canal POM TM ), and marsh plants were less important. Dietary contribution of microphytobenthos was highest in April to June, while decreased towards December owing to the supply of canal POM PP and canal POM TM following red tides and heavy rainfall events in summer to fall. Temporal changes in δ 15 N (Δδ 15 N) of consumer corresponded well to the 15 N-enrichment in canal POM PP in summer. A meta-analysis showed that the consumer-Δδ 15 N was considerably larger in inner Tokyo Bay than those in other estuaries, which may be a specific characteristic of benthic food web in highly urbanized estuaries.

Differences in biogenic phosphorus (P) compounds between sediment and suspended particles in aquatic environments are important for understanding the mechanisms of internal P loading, but these differences are still unknown. We used solution-state (31)P-nuclear magnetic resonance spectroscopy ((31)P NMR) with NaOH-ethylenediaminetetraacetic extraction to detect the multiple P compounds in suspended particles and sediment in the eutrophic Lake Kasumigaura, including orthophosphate monoesters, orthophosphate diesters, pyrophosphate, and polyphosphate. We tested the hypothesis that there is a significant difference between these groups in suspended particles and sediment. Biogenic P other than orthophosphate was found in significantly higher proportions in suspended particles (74.3% of total P) than in sediment (25.6%). Orthophosphate monoesters were comparatively more abundant in suspended particles, as indicated by the ratio of orthophosphate diesters to monoesters (average, 0.31 for suspended particles; 1.05 for sediment). The compounds identified as orthophosphate monoesters by (31)P NMR spectroscopy originated mainly from phospholipids (α-glycerophosphate and β-glycerophosphate) and ribonucleic acid (RNA-P), whereas the orthophosphate diesters included mostly DNA (DNA-P). These results suggest that the dynamics of orthophosphate diesters, the production of DNA-P, or the degradation of phospholipids, play an important role in P cycling in Lake Kasumigaura.

Pulverization devices of toner were studied experimentally as well as numerically in the point of view of fluid dynamics. Supersonic flow, into which raw toner powder is poured through an injector, is injected against a flat plate or a coneshape obstacle. After passing through a shock wave formed in front of the obstacle, the raw toner powder is produced.Based on the flow visualization study together with numerical analysis of the flow field, the velocity field and the pressure and the density distributions are determined. As the results, the optimum shape of the obstacle and the flow conditions are found.

In sediment trap materials or suspended particulate organic matter, δ13C values must be averaged over at least several years to determine δ13C shifts during sedimentation. To overcome this problem, we studied isotopic modification of sedimentary organic carbon during early diagenesis in sediment samples collected intermittently from a site at the center of Lake Kasumigaura, Japan, over a period of nearly 30 years, beginning in 1979. We examined the degree of apparent isotope discrimination by comparing long-term changes in the carbon isotope composition of the surface sediment (top 2 cm) with the isotope composition profile from 0 to 15 cm. The downcore C isotope composition profile was close to the values calculated from the long-term changes in the isotope composition of the surface sediment, suggesting that the sedimentary carbon isotope composition was generally conserved (±0.6‰) during early diagenesis (up to 30 years). However, at greater core depths, significant 13C enrichment of up to 1.5‰ was sometimes observed, especially in the periods of relatively oxidative conditions.

[1] To clarify the pathways and origins of dissolved nitrate (NO3−) in rivers flowing into Lake Biwa, Japan, three types of coordinated surveys of concentrations and isotope compositions of NO3− were conducted: (1) synoptic river sampling of 32 representative inflow rivers, (2) two rivers in catchments with different land uses, and (3) headwater catchment samplings. The data set used in this paper is the first comprehensive collection of isotopic composition of NO3− in rivers of a large-scale basin in Asia. While the NO3− spatial concentration pattern showed significant seasonal variation, the spatial pattern of the δ15N of dissolved NO3− was more consistent throughout the year. The was significantly positively correlated with the population density of each catchment. A mass balance model assuming the and the flow rate of sewage effluent was developed. The model simulated the relationship between the population density and the reasonably well, suggesting that the dominant source contributing to the increase in was the sewage effluent. The spatiotemporal distribution of suggested the possibility of the addition of atmospherically derived NO3− through precipitation and was indicated by the hydrological pathways for NO3− exports in different land uses. In forest-dominated catchments with natural drainage systems, a slightly elevated δ18ONO3 signal remained in the stream water even during base flow conditions. This study demonstrated that multiscale, multi-isotopic investigation is a promising strategy for describing the spatial distribution of NO3− sources synoptically and is useful for evaluating the influences of land use change.

This paper deals with the effects of strain rate on the mechanical properties of base metals, buttwelded joints, high-strength bolted joints and regular bolted joints due to cyclic reversed loadings. The increase of the yield strength and the ultimate strength of the base metals was significantly observed under the monotonic loading conditions. However, under cyclic loading conditions, the effect of strain rate on the mechanical properties were various in different joint types. From the results, it can be seen that the particular attention should be paid on the design of bolted joints, especially, in stell structures with short natural periods.

Forming Limit Diagrams (FLDs) of a magnesium alloy (AZ31) sheet at various forming speeds (3 to 300 mm·mm-1) at several temperatures of 100-250°C were investigated by performing a punch stretch-forming test. The forming limit strains increased with temperature rise and with decreasing forming speed, where the effect of forming speed was stronger at higher temperatures. To describe such a characteristic of FLD of AZ31, the Marciniak-Kucznski type forming limit analysis was conducted using the Backofen-type constitutive equation (c = Cεnεm). In this analysis, the damage evolution in the necking zone was taken into account based on Oyane's ductile fracture criterion. The numerical results of the FLD show a good agreement with the corresponding experimental observations.

The liverwort Marchantia polymorpha L. synthesizes arachidonic (ARA) and eicosapentaenoic acids (EPA) from linoleic and alpha-linolenic acids respectively by a series of reactions catalyzed by Delta6-desaturase, Delta6-elongase, and Delta5-desaturase. Overexpression of the M. polymorpha genes encoding these enzymes in transgenic M. polymorpha plants resulted in 3- and 2-fold accumulation of ARA and EPA respectively, as compared to those in the wild type. When these three genes were introduced and co-expressed in tobacco plants, in which long-chain polyunsaturated fatty acids (LCPUFAs) are not native cellular components, ARA and EPA represented up to 15.5% and 4.9% respectively of the total fatty acid in the leaves. Similarly in soybean, C20-LCPUFAs represented up to 19.5% of the total fatty acids in the seeds. These results suggest that M. polymorpha can provide genes crucial to the production of C20-LCPUFAs in transgenic plants.

This paper refers to deforambility of double-Warren truss tower structures composed ofcircular hollow sections, which are widely used in constructing steel towre structures. In currentdesign practice, the structures are regarded as being collapsed as a whole, when buckling in aprimary compressed member occurrs, strength and deformability of the structures are not takeninto account in the post buckling range. In order to improve the durability of the structure, itis desired to design so that buckling of the primary member does not lead to the collapse of thestructure.A method to improve deformability of the structure by adding bending resistant members isproposed. In order tomake clear stability and deformabilkity of the proposed structures in com-parison with those of ordinary truss structures, an experimental investigation was carried outusing subasseinblages of truss structure.

Y chromosomes are different from other chromosomes because of a lack of recombination. Until now, complete sequence information of Y chromosomes has been available only for some primates, although considerable information is available for other organisms, e.g., several species of Drosophila . Here, we report the gene organization of the Y chromosome in the dioecious liverwort Marchantia polymorpha and provide a detailed view of a Y chromosome in a haploid organism. On the 10-Mb Y chromosome, 64 genes are identified, 14 of which are detected only in the male genome and are expressed in reproductive organs but not in vegetative thalli, suggesting their participation in male reproductive functions. Another 40 genes on the Y chromosome are expressed in thalli and male sexual organs. At least six of these genes have diverged X-linked counterparts that are in turn expressed in thalli and sexual organs in female plants, suggesting that these X- and Y-linked genes have essential cellular functions. These findings indicate that the Y and X chromosomes share the same ancestral autosome and support the prediction that in a haploid organism essential genes on sex chromosomes are more likely to persist than in a diploid organism.