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The PtO2-catalyzed hydrogenation of curcumin produced slightly predominant meso-octahydrocurcumin than raceme octahydrocurcumin. Similar result was found in the product obtained from tetrahydrocurcumin and NaBH4, whereas using palladium carbon as a catalyst increased the meso-octahydrocurcumin ratio. Compared with chemical methods, baker's yeast produced 3S,5S-octahydrocurcumin and meso-octahydrocurcumin from tetrahydrocurcumin. The different activity between raceme and meso-octahydrocurcumin was not found in our experiments.

A hexahydrocurcumin-producing bacterium named 2a1-2b was isolated from human feces. It was observed that the bacterium had more than 99% similarity with Enterococcus avium ATCC14025T according to 16S ribosomal DNA (rDNA) sequence. The strain 2a1-2b produced optically active 5R-hexahydrocurcumin (enantiomeric excess (e.e.) > 95%) from tetrahydrocurcumin but not from curcumin. Our results showed that intestine is an important place for producing hexahydrocurcumin.

Although many in-service welded built-up structures, which contain many welded joints as fatigue crack initiation sites, are subjected to many types of loading, their structural integrities are evaluated according to design codes based on theoretical and experimental investigations under uniaxial loading conditions. Additionally, most of these codes implement the S–N curves approach. This study highlights the biaxial cyclic loading with different phases. The fracture mechanics approach toward fatigue life evaluation can obtain the fatigue crack growth history. This paper confirms the applicability of the previously proposed numerical simulation method for obtaining the fatigue crack propagation histories of a cracked plate subjected to biaxial loads with a phase difference for each loading component. A fracture mechanic approach was used to establish the proposed method. The fatigue surface crack growth behavior of a flat plate and an out-of-plane gusset-welded joint under biaxial cyclic loadings with different phases was investigated by extending the applicability of the proposed method to a through-thickness crack. Comparisons between the measured crack evolution and the numerical simulation results were carried out to validate our fatigue crack growth simulation for flat plane and welded joints.

Equol, an intestinal metabolite of daidzein, inhibited more potently mushroom tyrosinase in vitro than other inhibitors, genistein and kojic acid. We investigated the mechanism underlying tyrosinase inhibition by equol. Treating racemic equol with tyrosinase produced 3'-hydroxyequol. Because the optical activity of the product showed

A hexahydrocurcumin-producing bacterium named 2a1-2b was isolated from human feces. It was observed that the bacterium had more than 99% similarity with Enterococcus avium ATCC14025

Equol, an intestinal metabolite of daidzein, inhibited more potently mushroom tyrosinase in vitro than other inhibitors, genistein and kojic acid. We investigated the mechanism underlying tyrosinase inhibition by equol. Treating racemic equol with tyrosinase produced 3'-hydroxyequol. Because the optical activity of the product showed25% enantiomeric excess, the reaction was not highly stereospecific. Using enzyme-linked immunosorbent assays with an anti-equol monoclonal antibody, we observed that equol bound to pre-coated tyrosinase in a dose-dependent manner. Our results suggested the formation of a stable equol-tyrosinase complex.

S-Equol is a metabolite of daidzein, a type of soy isoflavone, and three reductases are involved in the conversion of daidzein by specific intestinal bacteria. S-Equol is thought to prevent hormone-dependent diseases. We previously identified the equol producing gene cluster (eqlABC) of Eggerthella sp. YY7918. Daidzein reductase (DZNR), encoded by eqlA, catalyzes the reduction of daidzein to dihydrodaidzein (the first step of equol synthesis), which was confirmed using a recombinant enzyme produced in Escherichia coli. Here, we purified recombinant DZNR to homogeneity and analyzed its enzymological properties. DZNR contained FMN, FAD, and one 4Fe-4S cluster per 70-kDa subunit as enzymatic cofactors. DZNR reduced the C C bond between the C-2 and C-3 positions of daidzein, genistein, glycitein, and formononetin in the presence of NADPH. R-Dihydrodaidzein and R-dihydrogenistein were highly stereo-selectively produced from daidzein and genistein. The Km and kcat for daidzein were 11.9 μM and 6.7 s−1, and these values for genistein were 74.1 μM and 28.3 s−1, respectively. This enzyme showed similar kinetic parameters and wide substrate specificity for isoflavone molecules. Thus, this enzyme appears to be an isoflavone reductase. Gel filtration chromatography and chemical cross-linking analysis of the active form of DZNR suggested that the enzyme consists of an octameric subunit structure. We confirmed this by small-angle X-ray scattering and transmission electron microscopy at a magnification of ×200,000. DZNR formed a globular four-petal cloverleaf structure with a central vertical hole. The maximum particle size was 173 A.

Manuka honey is known as one of the premium honeys because of its unique property: a potent antibacterial activity. Leptosperin, methyl syringate 4-O-β-d-gentiobioside, has been specifically identified in manuka honey. Because leptosperin is relatively stable under warmer conditions, measuring leptosperin levels may be applied to authenticate manuka honey. In this study, an immunochromatographic separation and quantification of leptosperin techniques have been developed. The concentration of leptosperin measured by immunochromatography was significantly correlated with the concentration measured by high-performance liquid chromatography (HPLC) or enzyme-linked immunosorbent assay (ELISA). Because the immunochromatographic method is rapid and reliable, it could be applied to on-site quality control or inspection of honey samples by a beekeeper, a manufacturer, an inspector, a retailer, or a consumer.

Daidzein (DZN) is converted to equol (EQL) by intestinal bacteria. We previously reported that Eggerthella sp. YY7918, which is found in human feces, is an EQL-producing bacterium and analyzed its whole genomic sequence. We found three coding sequences (CDSs) in this bacterium that showed 99% similarity to the EQL-producing enzymes of Lactococcus sp. 20-92. These identified CDSs were designated eqlA, eqlB, and eqlC and thought to encode daidzein reductase (DZNR), dihydrodaidzein reductase (DHDR), and tetrahydrodaidzein reductase (THDR), respectively. These genes were cloned into pColdII. Recombinant plasmids were then introduced into Escherichia coli BL21 (DE3) and DZNR, DHDR, and THDR were expressed and purified by 6×His-Tag chromatography. We confirmed that these three enzymes were involved in the conversion of DZN to EQL. Purified DZNR converted DZN to dihydrodaizein (DHD) in the presence of NADPH. DHDR converted DHD to tetrahydrodaizein (THD) in the presence of NADPH. Neither enzyme showed activities with NADH. THDR converted THD in the absence of cofactors, NAD(P)H, and also produced DHD as a by-product. Thus, we propose that THDR is not a reductase but a new type of dismutase. The GC content of these clusters was 64%, similar to the overall genomic GC content for Eggerthella and Coriobacteriaceae (56-60%), and higher than that for Lactococcus garvieae (39%), even though the gene cluster showed 99% similarity to that in Lactococcus sp. 20-92. Taken together, our results indicate that the gene cluster associated with EQL production evolved in high-GC bacteria including Coriobacteriaceae and was then laterally transferred to Lactococcus sp. 20-92.

Fatigue crack propagation under the biaxial tensile loading, which loading directions are normal and parallel to the initial crack position, is highlighted in this study. Most of in-service structures and vessels are subjected to many types of loading. Generally, these loadings have different axial components with different phases. However, the structural integrities of structures and vessels are evaluated according to design codes based on theoretical and experimental investigations under a uniaxial loading condition. Most of these codes are based on the S–N curves approach. An approach that does not use S–N curves has been favored by researchers, with the fracture mechanics approach preferred for evaluating the fatigue life of structures. An advanced fracture mechanics approach was developed based on the Re-tensile Plastic zone Generating (RPG) stress criterion for fatigue crack propagation. In this study, fatigue crack propagation tests under biaxial loading with six different phase and loading conditions are performed and the effect of the phase difference under biaxial loading is evaluated. A numerical simulation method of fatigue crack propagation based on the RPG stress criterion under different biaxial loading phase conditions is presented and compared to measured data.

We had isolated an O-desmethylangolensin (O-DMA)-producing bacterium, Clostridium rRNA cluster XIVa strain SY8519. According to chiral separation using HPLC, the SY8519-produced O-DMA exhibited high optical purity. To determine the absolute stereochemistry of O-DMA, we prepared 2-(4-hydroxyphenyl)propionic acid (2-HPPA) from the O-DMA using the Baeyer-Villiger reaction. From chiral analysis of the product, the major peak had the same stereochemistry to that of 2-HPPA produced from genistein by the same bacteria. As we have determined the stereochemistry of SY8519-produced 2-HPPA to have an R configuration, by the chemical synthesis of (S)-2-HPPA, the SY8519-produced O-DMA must also possess R stereochemistry at the 2-position. To study the stereoselective metabolism, we applied racemic dihydrodaidzein to SY8519. The O-DMA was isolated from the culture media and starting material was also recovered. The O-DMA produced was optically active in a similar manner to that produced from daidzein. However, the remaining dihydrodaidzein exhibited no difference between the enantiomers. These results suggested that SY8519 produces (R)-O-DMA from both enantiomers of dihydrodaidzein.

The effect of whipping vibration on the fatigue life was estimated for larger ship safety. Miner’s law and Fatigue crack propagation analysis were applied for the fatigue life estimation. The delay phenomenon occurring fatigue crack growth according to over loading caused by whipping were simulated by using non-linear fatigue crack propagation program. The simulated stress acting on deck structure of the actual post-panamax container ship were applied to numerical program, the whipping effect was evaluated by comparing with the superimposing vibration stress (RAW) and without vibration stress (LF). It was found that the effect is about 30% in Miner’s law and 10-55% in Fatigue crack propagation analysis assuming a long-term storm of 25 years in North Atlantic. The effect became smaller than those reported in the previous report (abt.50%), where a maximum storm was assumed. And, it was estimated that the effect of delay phenomenon is same level of the whipping effect. Furthermore, as an example of probabilistic approaches for fatigue life evaluation, structural reliability analysis in Monte Carlo simulation was performed in the parameters with the ship speed, wave direction, and the rank of storms. The effect of operating condition was quantitatively indicated by the reliability index and the failure probability. It was indicated that the effect of whipping on fatigue life can be canceled by operational effect of ship speed reduction in severe sea.

Hull girder stresses caused by the whipping vibration increases as ship size becomes bigger, and it is therefore concerned that design fatigue life of such large ship might be unconservative. In this study, in order to clarify effects of superposed elastic vibrations on linear wave loads in the fatigue life estimation. Using created time history of stress, numerical simulations for fatigue strength of a post-panamax container ship has been conducted. Random stress time history is created using a storm-model, and a high frequency stress model is proposed to estimate effects of the whipping vibration. Two kinds of evaluation methods are adopted. One is fatigue crack propagation analysis using fracture mechanics taking account of the nonlinear retardation phenomena. The other is fatigue damage factor based on Miner's Law. Results of the fatigue strength analysis in a period of the maximum storm condition for a ship's life in the North Atlantic show that the fatigue crack length obtained by the fatigue crack propagation analysis has a similar trend as the damage factor by Miner’s Law. With regard to the effect on the fatigue strength of the whipping, different treatments of high frequency stress to extract low frequency time history give different results. If the low frequency time-history (LF) is adopted, the difference is remarkable, the fatigue damage of RAW become approximately 50%-100% greater than LF. If the envelope time-history (ENV) is adopted, the difference is relatively small, e.g. 0.1-2.0%.

Leptosperin, a novel glycoside of methyl syringate, is exclusively present in manuka honey derived from the Leptospermum species Leptospermum scoparium. Quantification of leptosperin might thus be applicable for authentication of honey. The concentration of leptosperin has high linearity with antibacterial activity. We established a monoclonal antibody to leptosperin and characterized the antibody in detail by a competitive enzyme-linked immunosorbent assay (ELISA), comparing the results with those of the high-performance liquid chromatography (HPLC) method for validation. The antigen in manuka honey was confirmed as leptosperin by HPLC fractionation with quantitation by an ELISA. Leptosperin contents of 50 honey samples were analyzed by an established ELISA, which can handle 20 samples (duplicate) on one 96-well plate. Significant coincidence with the chemical quantitation was observed. Immunochemical quantitation of leptosperin would be an economical and facile method for the possible authentication of manuka honey, allowing many honey samples to be processed and analyzed by an ELISA simultaneously.

We tried to isolate metabolite in curcumin by incubation with human feces in vitro for the better understanding of curcumin activity in vivo. One group containing some bacteria, referred as 1C, produced a metabolite other than tetrahydrocurcumin. Structural analysis revealed that this new metabolite was 3-hydroxy-1,7-bis(3,4-dihydroxyphenyl)heptane by comparing it to the reported optically active compound rubranol, which has 3R stereochemistry. In order to determine the absolute stereochemistry of the secondary alcohol of this metabolite, we synthesized its racemic tetramethyl derivative. From HPLC analysis that separate the synthetic sample to two peaks, this metabolite was optically active and was primarily an enantiomer of rubranol. We also compared the activities of curcumin and the metabolite using monocyte chemoattractant protein-1 (MCP-1) which is produced in vitro by murine adipocytes. The metabolite exhibited an inhibition effect associated with the production of MCP-1, which was similar to that of curcumin with attenuated cytotoxicity.

Fatigue crack propagation under biaxial tensile loading containing phase differences is highlighted in this study. Ships and offshore structures are subjected to many types of loading, e.g. wave induced forces, gravity, and inertia forces. Generally, these loadings have different axial components with different phases. However, the structural integrities of structures and vessels are evaluated according to design codes based on theoretical and experimental investigations under a uniaxial loading condition. Most of these codes are based on the S-N curves approach. An approach that does not use S-N curves has been favored by researchers, with the fracture mechanics approach preferred for evaluating the fatigue life of structures. An advanced fracture mechanics approach was developed based on the Re-tensile Plastic zone Generating (RPG) stress criterion for fatigue crack propagation. In this study, fatigue crack propagation tests under biaxial loading with four different phase conditions and two different loading components are performed and the effect of the phase difference under biaxial loading is evaluated. The authors present a numerical simulation method of fatigue crack propagation based on the RPG stress criterion under different biaxial loading phase conditions and the validity of the proposed method is confirmed by comparing the estimated fatigue crack propagation histories with measured data.

Daidzein and genistein are the main aglycones of soy isoflavonoid, and have many useful activities in vitro and in vivo . However, equol, a metabolite of daidzein in vivo , has attracted attention due to its stronger activity than that of the naturally occurring isoflavonoids. We subjected the soy isoflavonoids, including the naturally occurring ( S )-equol, to mouse adipocytes, and compared the inhibitory activity on the leptin secretion. Equol, daidzein and genistein inhibited the leptin secretion, whereas O -desmethylangolensin had a lower activity. The inhibitory activity of the isoflavones was not affected by the addition of an iNOS inhibitor and an estrogen.

A bacterium that converted daidzein to O-desmethylangolensin was isolated from the feces of healthy humans. It was an obligately anaerobic, nonsporeforming, nonmotile and Gram-positive rod. The isolate used glucose, sucrose, raffinose, maltose, and fructose as carbon sources. It did not hydrolyze gelatin, esculin, or starch. The strain was urease, acid phosphatase, and arginine dihydrolase positive. It was catalase, oxidase, H(2)S, and indole negative. The major products of glucose fermentation were butyrate and lactate. Its mol% G+C was 51.2. The major cellular fatty acids were C(16:0) DMA, C(16:0), and C(16:0) aldehyde. The structural type of cell wall peptidoglycan was suggested to be A1gamma. The isolate was susceptible to beta-lactam, cefem, and macrolide antibiotics and resistant to aminoglycoside and quinolone antibiotics. The bacterium was related to Eubacterium ramulus ATCC29099(T), Eubacterium rectale ATCC33656(T), and species of the genus Roseburia, but the highest 16S rRNA gene similarity to these described species was only 94.4%, consistent with its being classified as a novel genus. Based on the above, the isolate, named strain SY8519, was identified as belonging to a novel genus in the Clostridium rRNA cluster XIVa.

Fatigue life estimation for planar cracks, e.g. part-through surface cracks or embedded cracks is very important because most of fatigue cracks found in welded built-up structures show planar crack morphologies. Although authors had proposed the estimation procedure of crack shape evolution for a planar crack based on the fracture mechanics approach, this method cannot apply if the values of stress intensity factor at the vertices of the surface crack approximated as an ellipse cannot calculated. Then, development of the shape evolution procedure of a planer crack under the stress field with arbitrary gradient, because fatigue cracks in welded built-up structures exist near the stress concentrated region. A Practical estimation formula the shape evolution of a surface crack under stress field with the gradient is proposed in this study. This formula is established by considering the stress field under no crack condition and some former proposed formulae under uniform and pure bending stress fields. The validity of the proposed formula are confirmed by comparing some measured surface crack shape evolutions under some stress gradient conditions.Copyright © 2015 by ASME

We previously isolated an O-desmethylangolensin (O-DMA)-producing bacterium, Clostridium rRNA cluster XIVa strain SY8519. We studied the metabolism of soy isoflavonoids by strain SY8519 and found that the bacterium attenuated the activity of isoflavonoids by “decomposition”. In this study, the O-methyl derivatives of isoflavones formononetin and biochanin A were fed to the bacterium. Formononetin and biochanin A were metabolized to O-DMA and 2-(4-hydroxyphenyl) propionic acid, respectively, which are the products of the original isoflavones. We could detect daidzein as an intermediate in the production of O-DMA from formononetin by time course analysis of the culture medium. Therefore, strain SY8519 can cleave the O-methyl ethers of isoflavones. We then examined the demethylation of O-methyl derivatives of gallic acid methyl ester by strain SY8519. The metabolite was almost 3-O-methylgallic acid methyl ester but not gallic acid ester. These results suggest that strain SY8519 also cleaves the O-methyl ethers of certain phenolic compounds by demethyl enzyme. We also compared the activities of the O-methyl derivatives of gallic acid methyl ester. As the number of the methyl ether decreased, the activities in tyrosinase inhibition and antioxidant assay increased. Therefore, compared with humans who have different microflora, humans who have strain SY8519 or who have similar microbial activity in their intestine would experience different effects after the intake of phytochemicals.

The Japan Agency for Marine-Earth Science and Technology (JAMSTEC) is planning scientific riser drilling for 4, 000 meters depth class risers in the future by utilizing the riser drilling vessel “Chikyu”. There are many technological problems in order to realize this plan, and it is very important to reduce the self weight for riser pipes in the deep sea. Titanium alloy with high specific intensity is considered to be a potential material of marine riser for the deep sea. Not much is known about the mechanical properties of titanium alloy as it is an industrially new material for marine riser, and in particular fatigue crack propagation properties are not enough.In this study, by using center notched specimens of Ti-6Al-4V alloy (ASTM Grade 5), fatigue crack propagation tests were carried out under constant amplitude loading in the air, seawater and seawater for charging the cathode potential of -0.8V (vs. SCE) and -1.2V (vs. SCE) on specimens. As a result, it became clear that fatigue crack propagation rate is influenced by the stress ratio and the cathode potential, though Ti-6Al-4V alloy shows a superior corrosion resistance in seawater.

A new parameter, which can quantitatively describe fatigue crack propagation, is proposed in this paper. This parameter reflects the cyclic plasticity behaviour near the crack tip, and the resulting built up of layers with the residual plastic deformations on the fatigue crack surfaces. A fatigue crack closure model suitable for an arbitrary applied stress distribution with an arbitrary residual stress distribution based on appropriately modified Dugdale’s concept of crack tip plasticity is developed. A re-tensile plastic zone generated (RPG) load, at which the tensile plastic zone starts to develop ahead of a crack tip, is defined. The effective stress intensity factor range is redefined by replacing the crack opening load with the RPG load. This redefined effective stress intensity factor is termed Δ K RPG . When Δ K RPG substitutes for Δ K or the crack opening load based on Δ K eff the “knee” in the threshold region of the crack growth data is not seen any longer. As a result, it is confirmed that a stopping phenomenon of a fatigue crack propagation can be quantitatively and appropriately described without the threshold value such as (Δ K eff ) th . It is also confirmed that the proposed crack closure model can provide quantitative estimates of the fatigue life under various loading conditions and in pre-existing residual stress field.

A new fatigue life evaluation methodology, which enables to predict fatigue crack growth from a stress concentration site without the initial defect is proposed. This method is based on the following scenario of fatigue crack growth: (i) a shear mode crack initiates and grows from the stress concentration site, (ii) a crack opening mode appears when the shear crack reaches the first grain boundary, (iii) the crack mode shifts from shear to opening/closing, (iv) opening/closing mode crack propagates. It is further assumed that cracked bodies which have the same stress intensity factor range (Δ K ) show the same fatigue crack growth. On the basis of this hypothesis, an equivalent distributed stress (EDS) is defined. EDS corresponds to the distributed stress in an infinite plane with a straight crack for which the relationship between the crack length and the stress intensity factor ( K ) is the same as in the considered cracked body. Estimation of fatigue crack growth from a sound stress concentration site in corner boxing joints is performed by applying a fatigue crack closure simulation code FLARP developed by the authors and using the EDS concept. The stresses due to the external loading and welding are converted into EDS in order to apply FLARP. The estimation procedure is validated by comparing the predicted and experimental results.

The oxindole-3-acetic acids, oxidative metabolites of indole-3-acetic acid, were isolated from a byproduct of a corn starch manufacturing plant, and were further converted to the 3-hydroxyl derivatives in the presence of metal ion. The mechanical study was followed by a chemical analysis including other byproducts, and suggested the presence of an intermediate that had a radical at the C-3 position of oxindole-3-acetic acids.

Nine different antibodies against P450 isoforms were prepared using purified cytochrome P450s (P450) expressed in E. coli. Purified isozymes were injected into rabbits to raise specific antibody. The resulting antibodies were characterized for their specificity and sensitivity through each particular P450 enzyme-mediated probe reaction.Anti-CYP1A2, CYP2A6, CYP2C8, CYP2C9, CYP2D6, CYP2E1, and CYP3A4 antibodies proved to be strong immunoinhibitors with inhibitory effects specific to their corresponding antigen. Antiserum derived from the CYP2C19-immunized rabbits was reacted with CYP2C9 as well as CYP2C19 and immunoabsorbed with membrane-bound CYP2C9 expressed in E. coli. Antibody specific for CYP2C19 was obtained. Anti-CYP2C19 together with the anti-CYP2C8 and anti-CYP2C9 can be very useful for determining the contribution of a particular P450 in the metabolism of a drug. The developed inhibitory antibodies will serve as in vitro-specific tools for evaluating the quantitative contribution of individual P450 enzymes to drug metabolism.

Bioassay guided fractionation from corn gluten meal, a byproduct of a starch manufacturing plant, gave N-p-coumaroyl-N'-feruloylputrescine (1) and N,N'-diferuloylputrescine (2) as alpha-glucosidase inhibitors. Some structure-activity relationships were studied by comparing the inhibitory activity by preparing some related compounds, and it was revealed that the hydroxyl group was important for the inhibitory activity of bisamide alkaloids, but not the redox potential.

Corrosion wastage has important roles for an evaluation of strength of aged hulls. Corrosion fatigue strength is also indispensable factor in health of hull strength with aged upper deck plates. From those backgrounds, corrosion and corrosion fatigue tests were performed under an environment substituted a vapor space of crude oil tankers. The vapor space is filled up with H2S gas comes from crude oils and an inert gas for preventing an explosion of cargo oil tanks (COT).A corrosion rate, 0.2mm/y, was estimated from a continuous corrosion test in the vapor space. The rate was twice as fast as measurement data of ships. The small corrosion diminution of the upper deck plate is caused by cycles of full load and ballast load conditions.S-N curves, Seq-Nc curves, ΔK-Nc curves and crack propagation limits were compared with the data of corrosion environments in seawater and dilute sulfuric acids. Crack initiation lives, Nc, were nearly equal to the lives in dilute sulfuric acids of pH4 and pH2 in a short life range. In a long life range, the lives of Kt=1.2 decreased to the lives in dilute sulfuric acids of pH4 and pH2, and the lives of Kt=>2.0 were nearly equal to the lives in seawater. An aspect ratio, 0.6, was obtained from corrosion pits to propagate as fatigue crack. The stress intensity factor range, ΔKCF=4.70 MPa•m1/2, was the lowest corrosion fatigue strength and the boundary level whether or not the corrosion pits grow into a fatigue crack or progress as corrosion wastage.

cope Manuka honey, which shows strong non-peroxide-dependent antibacterial activity, contains unique components, such as methyl syringate 4-O-β-D-gentiobioside (leptosperin) and its aglycone, methyl syringate (MSYR). To determine the potential for biological activity evoked by the ingestion of leptosperin and MSYR, we investigated the absorption and metabolism of these components in manuka honey. Methods and results The incubation of MSYR with liver microsomes or S9 fractions in vitro resulted in the formation of MSYR-glucuronide (MSYR-GA), MSYR-sulfate (MSYR-S), and syringic acid as metabolites. Then, manuka honey (15 g) was fed to healthy human volunteers. MSYR-GA, MSYR-S, and MSYR were detected in both plasma and urine. Within plasma, their levels were highest within 0.5 h to 1 h post-ingestion, and most metabolites disappeared within 3 h. In conjunction with the disappearances, a significant amount of metabolites along with trace leptosperin was excreted in urine within 4 h. To elucidate the detailed metabolisms of leptosperin and MSYR, each compound was separately administered to mice. In each case, MSYR-GA, MSYR-S, and MSYR were detected in both plasma and urine. Conclusion This study shows the major molecular pathway for leptosperin and MSYR metabolism and could facilitate an understanding of biological functions of manuka honey post ingestion. This article is protected by copyright. All rights reserved

Surface cracks emanated from stress concentration field occur at a lot of points and grow while repeating coalescence. However, it is difficult to find a regularity in the growth process for each surface crack. Therefore, in the previous paper, a supposed representative surface crack of which K value at the deepest point is the same as the increased K value due to the interference effect was introduced, which has the same depth of the largest surface crack. It became clear that the change of aspect ratio of a supposed representive surface crack decreases linearly as the surface crack grows.In this paper, it becomes clear that the change of aspect ratio of a supposed representive surface crack emanated from a notch or a toe of weld is estimated appoximately by the balanced growth curve of a semi-circular surface crack with the same size as grain size. And then, we carried out fatigue crack propagation analyses for fatigue tests with a gusset weld specimen by using an alogorithm of fatigue life assessment by ΔKRP approach without distinguishing between the crack initiation and the crack propagation. As a result, it is confirmed that the estimated S-N curve is in good agreement with the experimental one.

In the previous paper, we developed a simulation model of fatigue crack opening and closing phenomena for predicting RPG load under an arbitrary stress distribution field. By using the simulation model, effects of stress ratio and residual stress distribution on fatigue crack propagation rate are quantitatively assessed. However, it became clear that the estimated fatigue life is longer than experimental one under decreased maximum load while keeping minimum load and a overload condition.In this paper, we considered the plastic shrinkage at an immediate generation of new crack surface for the purpose of solving the above problem and modified the above simulation model. And then, we carried out fatigue crack propagation analyses under various conditions and compared the estimated RPG loads and crack growth curves with the experimantal ones. As a result, it is confirmed that modified simulation model is appreciable to various amplitude fatigue loading tests.

We prepared soy isoflavonoids related to equol, a potent estrogenic compound metabolized from daidzein. These products were subjected to a competitive enzyme-linked immunosorbent assay to obtain highly selective anti-equol monoclonal antibody.

We consider some time-reversible cellular automata on thed-dimensional integral latticeZ d and study their time evolution properties. We show first that a Boltzmann-type entropy can be defined which is not less than its initial value for initial States which have no spatial correlation. For monotonic increase of the entropies for such initial States we need an additional condition which we call renewality. Under the renewality condition entropy is monotonic nondecreasing. We give some examples of cellular automata which satisfy the renewality condition

Previous papers have shown ΔKRP to be a useful parameter describing fatigue crack propagation behavior, where ΔKRP is an effective stress intensity factor range corresponding to the excess RPG load (re-tensile plastic zone's generated load) in which the retensile plastic zone appears under the loading process. In this paper, the relationship between ΔKRP and the zone size ( ω ) (which is smaller between the tensile plastic zone at maximum load and the compressive plastic zone at minimum load) was investigated using a crack opening/closing simulation model so as to consider a physical meaning of ΔKRP. As a result, it becomes clear that ΔKRP dominates the zone size ω where fatigue damage mostly occurs. This result supports the following crack propagation equation d a d N =C( ω ) m where C and m are material constants. Simulation and fatigue crack propagation tests were then carried out for compact tension (CT), center cracked tension (CCT) and four points bend (4PB) specimens under constant amplitude loading to obtain C and m values for HT-50 steel. Fatigue crack propagation tests were also carried out under constant amplitude loading using CCT specimens with residual stress distribution due to flame gas heating at the center line or edge lines. The T specimen introduced tensile residual stress at the tip of a notch, and the C specimen introduced compressive residual stress. It therefore becomes clear that tensile residual stress leads to a decrease in RPG load, while compressive residual stress leads to increase in RPG load, and that the simulation results are in good agreement with the experimental RPG load. It also becomes clear that simulated crack growth curve using the simulated ω and the above equation is in good agreement with the experimental curve. It is understood that tensile residual stress creates only a slight increase in crack propagation rate and compressive residual stress create a big decrease a crack propagation rate.

Fatigue crack propagation under biaxial tensile loading is highlighted in this study. Ships and offshore structures are subjected to many types of loading, e.g. wave induced forces, gravity, and inertia forces. Generally, these loadings have different axial components with different phases. However, the structural integrities of structures and vessels are evaluated according to design codes based on theoretical and experimental investigations under a uniaxial loading condition. Most of these codes are based on the S-N curves approach. An approach that does not use S-N curves has been favored by researchers, with the fracture mechanics approach preferred for evaluating the fatigue life of structures. An advanced fracture mechanics approach was developed based on the Re-tensile Plastic zone Generating (RPG) stress criterion for fatigue crack propagation. In this study, fatigue crack propagation tests under biaxial loading with four different phase conditions are performed and the effect of the phase difference under biaxial loading is evaluated. A numerical simulation method of fatigue crack propagation based on the RPG stress criterion under different biaxial loading phase conditions is presented and compared to measured data.

In the previous paper, we showed that logarithmic curve of da/dNΔKRP was linear even in the range of stage I as well as stage II of a long crack. Moreover we developed the simulation model of fatigue crack opening and closing phenomena in an arbitrary stress distribution field for the purpose of obtaining RPG load. By using the simulation model, effects of stress ratio and delayed retardation on fatige crack propagation are quantitatively assessed.In this paper, for the purpose of understanding the physical meaning of ΔKRP, the relation between ΔKRP and the zone size (ω) which is smaller size between tensile plastic zone at maximum load and compressive plastic zone at minimum load in one loading cycle is investigated by using the simulation model. As a result, it becomes clear that ΔKRP represents indirectory the zone size 63 recieving fatigue damage ahead of a crack.On the other hand, the equivalent distribution stress is introduced for the estimation of fatigue crack propagation life in complex elements, which is difined as stress distribution in an infinitely wide plate giving the same K value in the elements. Then fatigue life is assessed by using the simulation program inputting the equivalent distribution stress. Estimated fatigue life is good agreement with experimental one under constant amplitude loadings and storm model loadings. However estimated fatigue life is longer than experimental one under overload condition.

The strength and morphology of the weld region of injection molded test pieces of a polymer alloy of modified Polypropylene (m-PP) and Polyamide (PA) were studied.The effect of the composition and viscosity of m-PP, the condition of the reactive processing of PA and PP on the weld strength were examined.FT-IR analysis confirmed the reaction between Anhydride group of Maleic m-PP and Amino group of PA. That new formation of covalent bonds is assumed to make the alloy compatible.A microscopic observation of the weld region aswell as the strength of the weld test pieces, suggested the weld strength strongly depended on the morphology of the weld region. The small size (

In the previous paper, a simulation model of fatigue crack opening and closing phenomena in an arbitrary stress distribution field for the purpose of obtaining RPG load is shown.From the calculation and experimental results of RPG load, the effects of stress ratio and delayed retardation on fatigue crack propagation are quantitatively assessed. Moreover it becomes clear that the stopping condition of fatigue crack propagation is ΔKRP≤0.In this paper, fatigue crack propagation tests in residual stress distribution field are carried out. Two types of center notched specimens are prepared : one is that gas heating is made at the center line of the specimen which leads to tensile residual stress field in the middle part of the specimen, the other at near the edges of the specimen which leads to compressive residual stress field in the middle part of the specimen. It becomes clear that tensile residual stress descends RPG load and compressive residual stress raises RPG load. Moreover if the large compressive residual stress exists, crack closes even when tensile yield zone generates at the crack tip under loading process. In this case, plastic zone could not grow until crack becomes fully open.Simulated RPG load is in good agreement with experimental one even in the field of residual stress distribution. And compressive residual stress has a large effect of decreasing the fatigue crack propagation rate. These effects can be successfully estimated by the simulation model.

The cross section of a surface crack at the centre of a crack is a single edge cracked plate. Crack opening displacement of a surface crack at the centre can be modified to a single edge crack with springs of which the gauge length is zero and which correspond to the centre cracked plated. The centre cracked plate can be represented by series springs for cracked part and solid part. From the above relations, an analytical calculation was made of the crack opening displacement which may correspond to that for a surface crack by using the reciprocal principle. The K value at the deepest point of a surface crack can be obtained by suing the solution of working stress in series springs. The K value was calculated by a series springs model for a semi-elliptical surface crack with various crack sizes in a plate subjected to tension or bending loading. These results are in good agreement with published K values.

Soy isoflavonoids have many useful properties. However, they are metabolized in vivo, including in humans. The effect of the metabolism of soy isoflavonoids on their properties is not fully understood. We have isolated the bacterial strain SY8519, which has been shown to metabolize daidzein to O-desmethylangolensin and to produce 2-(4-hydroxyphenyl)propionic acid from genistein. According to chiral HPLC analysis, the 2-(4-hydroxyphenyl)propionic acid obtained from the bacterium was optically active. To determine the absolute stereochemistry of the microbial product, we prepared (S)-2-(4-hydroxyphenyl)propionic acid from (S)-2-phenylpropionic and concluded that the microbial product had an R-configuration by chiral HPLC analysis. We also applied the metabolite to mouse adipocytes and found that 2-HPPA was less effective at reducing leptin secretion than the parent compound genistein. Our results suggested that 'O-desmethylangolensin-production' attenuates the effect of soy isoflavonoids by reducing not only the activity of daidzein but also that of genistein.

Fatigue crack propagation tests with various stress ratios and stepwise decreasing maximum load while keeping minimum load are carried out for center notched tension specimens. In these tests, RPG load (Re-tensile Plastic zone's Generated load), crack length and number of cycles are measured by using our newly developed measuring system in the 1st report.We also calculate RPG load by using our developed simulation model of crack opening/closing phenomena based upon Dugdale model in the 5th report with various shrinkage coefficients α of plastic deformation due to emancipate internal force in newly generated crack surface at an immediate crack growth. Then we obtain α value for the steel used with comparing between simulated RPG load and measured one for the testing condition of R=0.05. By using the obtained α value, RPG loads for other stress ratios (R=0.3 and 0.5) are calculated by using the simulation model. As a result, simulated RPG loads are in very good agreement with measured RPG loads for R=0.3 and R=0.5.Then a crack growth curve for each testing condition is calculated by using ΔKRP from simulated RPG load and also shows in very good agreement with measured crack growth curve for each stress ratio.RPG load increases just after decreasing maximum load and reaches maximum and then decreases gradually as a crack advances in the cases of decreasing load with small magnification. Then delayed deterdation effects appear and delayed life increases with larger decrement of maximum load. It is also comfirmed that simulated RPG load using above α value is in good agreement with measured RPG load for these cases. It becomes also clear that crack growth curve in case of decreasing maximum load can be assessed quantitatively by using ΔKRP based upon the simulated RPG load.Moreover it is confirmed that larger decrement of maximum load in stepwise loading leads to stopping a crack even when final maximum load with large decrement of maximum load is larger than RPG load. This is because RPG load increases rapidly just after decreasing maximum load and approaches to final maximum load in case of large decrement of maximum load both in experiments and simulations. Simulated crack growth curve by ΔKRP using calculated RPG load in this case is also in good agreement with experimental one.Therefore it can be expressed that the condition of stopping a crack is ΔKRP_??_0 for a long crack. In other word, it becomes clear that ΔKth or (ΔKeff)th is not a material constant.