A methanol extract of the flowers of Mammea siamensis (Calophyllaceae) was found to inhibit enzymatic activity against aromatase (IC₅₀=16.5 µg/mL). From the extract, two new geranylated coumarins, mammeasins (1) and (2), were isolated together with seven coumarins: -hydroxy-5-methyl--(3,-dimethyl-octa-2,-dienyl)--(2-methyl-1-oxobutyl)-4,5-dihydropyrano[4,3,2-de]chromen-2-one (), -hydroxy-5-methyl--(3,-dimethyl-octa-2,-dienyl)--(3-methyl-1-oxobutyl)-4,5-dihydropyrano[4,3,2-de]chromen-2-one (10), mammeas A/ (14), A/ (15), A/ cyclo (18), /BA (23), and /BC cyclo (25). The structures of 1 and 2 were elucidated on the basis of spectroscopic evidence. Among the isolates including 17 previously reported coumarins, 1 (IC₅₀=2. µM), 2 (3. µM), and mammea B/ cyclo (21, 3.1 µM) showed relatively strong inhibitory activities comparable to the activity of the synthetic nonsteroidal aromatase inhibitor aminoglutethimide (2.0 µM).

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Repetitive liquefactions in angular and subangular gravels from an alluvial fan, in the case of two earthquakes with accelerations lower than that of a former which had caused liquefaction some months before, are described. The liquefaction took place from the surface, down to a depth of approximately 10 m. Water laden with sediments spouted out for some tens of minutes after the strong motion ceased. Knowledge of the grain size distribution of the sediments inside the body of the alluvial fan roughly defines the areas of the fan prone to future liquefaction. Non-repetitive liquefaction in overconsolidated fine fluvio-lacustrine sand of glacial origin at the unusual depth of 14 m to 16 m is also described. From the observation of sand lifted up for 10 m inside a large diameter well, and of that which spouted out from several microvents, it was estimated that extra-pore pressure was close to lithostatic conditions. Nevertheless, modeling of intrinsic pore pressure buildup on the DESRA2 programme gives lower values than the experimental one. Geotechnical characteristics of the 12 m-thick sandy stratum indicate that the upper part is unusually soft, either due to water circulation or past repetitive liquefactions which prevented reconsolidation. It is suggested that excess pore pressure generated by the earthquake was also due to redistribution of pressure from adjacent sediments.

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A new analytical method is proposed for determining the inextensible grid reinforcement pullout resistance and pullout force/pullout displacement curve by using basic backfill soil and grid reinforcement properties. The pullout skin friction resistance/pullout displacement relationship is simulated by linear elastic-perfectly plastic model. A hyperbolic model has been proposed to represent the pullout bearing resistance/pullout displacement relationship in which the maximum bearing resistance of a single bearing member is determined using a new bearing capacity equation proposed in this paper. The influences of the grid bearing member spacing ratio, S/, the bearing member deflection rigidity, and the pullout softening behavior on the mobilization of pullout bearing resistance are explicitly included in the proposed model. Good agreement has been obtained between calculated values and laboratory test results.

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Two new partially saturated tricyclic ring systems, , a, , , , 10, 10a, 11-octahydro-11-oxodibenz [b, ] oxepins (3a and 3b), and -thiepins (4a and 4b) were synthesized. Compounds 4a and 4b were desulfurized to give a pair of isomeric 2-methylbenzoylcyclohexanes (10a and 10b). Deuterated 4a and 4b (11a and 11b) were prepared starting from butadiene- (12). The stereochemical features of 3a (trans), 3b (cis), 4a (trans) and 4b (cis) are compared with those of 10a, 10b, 11a and 11b on the basis of proton nuclear magnetic resonance data.

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The Beckmann rearrangement of aliphatic ketone oximes, R(CHs)=NOH (R=Et (1); n-Pr (2); iso-Pr (3); iso-Bu (4)), with polyphosphoric acid (PPA), polyphosphate ester (PPE), and ester of phosphoric acid (2 P-5 R) was carried out and migratory ratios ((a)/(b) in eq. (1)) were determined, The results are shown in Fig.1, 2, and 3, respectively.
In Fig.1 and 2, the migratory ratios decrease with reaction time and nearly approach to the ratios of anti-alkyl form/syn-alkylform in benzene(A1) or DMSO(A2)except for (3) (See Table 1). From this fact, it has been found that PPA and PPE are inactive for isomerization of the oximes andanti-alkyl oximes rearrange faster than syn-alkyl ones. ln the case of (3), migratery ratios are smaller than Ai or A2. As acetonitrile is detected by GLC, it is presumed that fission has been occurred simultaneously with rearrangement in anti-alkyl oxime (eq. (3)). In the case of 2 P-5 R, all modes of the reaction arethe same as in above, except that the rate of fission is tnuch faster than that in PPA and PPE.
The reaction of anti-alkyl ketone oximes having a bulky grouphas been greatly influenced by the use of sterically demanding catalysts such asPPA, PPE, and 2 P-5 R.

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From the fronds of Polystichum tripteron (KUNZE) P_R. a new norcarotenoid glycoside was isolated and shown to be (R, , R)--hydroxy-megastigma-4, -dien-3-one--O-β--glucoside. The fronds of Dennstaedtia wilfordii (MOORE) CHRIST. contain the same glucoside.

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Incoherent scatter spectra for a plasma with a negative ion component are calculated successively by the kinetic and hydrodynamic approaches. It is shown that mesospheric negative ions enhance significantly the scattered power and the width of the ion component of the incoherent scatter spectrum. A simplified method is proposed for determining the mesospheric parameters from the measured incoherent scatter spectrum.

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Circuit techniques to enhance the linearity of input-voltage-to-current (V/I) conversion and to increase the output impedance of a current source by compensating for the low intrinsic gain of a transistor were introduced to realize a high-frequency operational transconductance amplifier (OTA) for a low supply voltage using sub-100-nm CMOS processes. Applying these techniques, a MOS th-order Gm- linear-phase low-pass filter (LPF) was realized using a 65nm CMOS process. A simplified biquad LPF that can serve as a component of a th-order LPF was newly developed by replacing OTAs with resistors. As a result, the -3dB frequency bandwidth, group delay ripple, 3rd-order distortion, and 3rd-order input intercept point (IIP3) were 200MHz, 2.2%, ≤ -55dB with a 100MHz input, and +10.3dBm, respectively, all with a ±0.1Vp-p input signal at each input terminal in the pseudodifferential configuration. The LPF including an output buffer dissipated 60mW in the case of a 1.2V supply. Wide spurious-free dynamic range (SFDR) characteristics were confirmed up to high frequencies.

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Agaricus blazei is an important fungus for producing bioactive compounds. There are some reports of polysaccharides and steroid derivatives from the fruiting bodies of A. blazei. However, the chemical examination of the secondary metabolites of the cultured mycelia of this species has not been reported. Eight compounds, an unprecedented skeleton have been isolated from the cultured mycelia of A. blazei. The structures of the novel compounds each named blazeispirols A (1), B (2), (3), (4), (5) X(), Y () and Z () were confirmed by extensive 1 and 2 NMR spectral data and X-ray analysis. Blazeispirols A (1), B (2), (3), (4) and (5) were des-A-ergostane type compounds having spiroacetal structure as a side chain. Blazeispirols X () and Y () were determined to be (20S, S, 23R, 24S)-1 (10→) abeo-14β, :, 25-diepoxyergosta-5,,,11-tetraene-3α,23-diol and (20S, S, 23R, 24S)-14β,:,25-diepoxy-,23-dihydroxyergosta-4,,11-triene-3,-dione by comparison of extensive 1 and 2 NMR spectral data with that of blazeispirol A. The biosynthesis of blazeispirol A was investigated by feeding ^<13>-labeled acetates and methionine to the growing cultures of A. blazei. The labeling patterns of 1 derived from singly and doubly ^<13>-labeled acetates were consistent with that of ergosterol reported previously except for the A-ring and then ^<14>-labeled ergosterol was incorporated into blazeispirol A. Taking the structures of blazeispirols Z and into consideration, it can be assumed that blazeispirol A is biosynthesized from ergosterol by the cleavage of -4, -5 and -1, -10 bonds on retro aldol condensation and Michael reaction via such as intermediate A as shown in Fig. 4. A large number of ergostane-type steroids have been isolated from many fungi. However, blazeispirol A is the first example of a naturally occurring des-A-ergostane-type steroid including a spiroacetal structure moiety as a side chain.

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11-Amino-, a, , , , 10, 10a, 11-octahydrodibebenzo[b, ]thiepines (a-) and -oxepines (a-) were synthesized by the Leuckart reaction of , a, , , , 10, 10a, 11-octahydro-11-oxodibenzo[b, ]thiepines (1a, b)and -oxepines (2a, b) followed by hydrolysis of the reaction products 4a- and 5a-, respectively. The four diastereomers, cis(a-H, 10a-H)-cis(10a-H, 11-H) a and a, cis(a-H, 10a-H)-trans(10a-H, 11-H) b and b, trans(a-H, 10a-H)-trans(10a-H, 11a-H) and , and trans(a-H, 10a-H)-cis(10a-H, 11-H) and , were isolated and their configurations and conformations were elucidated by chemical methods together with ¹H-nuclear magnetic resonance spectroscopic and X-ray crystallographic analyses.

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Natural sedimentary clays exhibit ageing effects on their behaviour when subjected to both consolidation and shearing. Attempts to characterising the in-situ 'structure'of soft marine clays have been made in case studies performed in Ariake (Japan) and in Bangkok (Thailand), each showing a typical profile of aged clay-structure with depth reflecting its site-specific geological consolidation history. In each site, profiles of Atterberg limits, natural water content, overconsolidation ratio (OCR), quasi-elastic shear modulus G_max and the undrained shear strength c_u with depth were attained from various laboratory tests, together with the a comparable profile of quasi-elastic shear modulus from insitu seismic survey G_f. Quantitative assessment of the aged clay-structure was made by using two different measures, metastability index MI (G) and the soil constant reflecting structure S (Jamiolkowski et al., 1994). The profiles of MI (G) and the S-value with depth were both determined based on the corresponding G_max behaviour of the reconstituted sample. "Disturbance"of laboratory samples retrieved by using two different samplers (i.., Laval and Japanese thin-walled samplers) with two different sampling techniques (i.., pre-boring and displacement methods) was discussed. A new approach to estimate c_u"in the ground", termed by the authors the MILK (Metastability Index coupled with Laboratory K_o test) method, is proposed. A trial of the MILK-method is demonstrated in soft Bangkok clay, the texture of which is similar to "soft cheese".

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Examination of the secreted wax of a scale insect, Ceroplastes ceriferus has shown the presence of various compounds of considerable biogenetic interest. (a) The sesquiterpenes were enantiomeric with respect to those from . rubens, which infests the same host tree. Each insect may possess a specific set of - cyclases for the formation of sesquiterpenes. (b) Among the identified twelve diterpenes, two of labdane skeletons were the first naturally occurring compounds. () The sesterterpenes (1-)(-10) having 14-membered monocyclic skeletons were the first naturally occurring compounds being independent of the host tree. Remarkable is the finding of sesterterpenes resulting from different biogenetic cyclization mode from the same species, collected in different districts, or from the different species of the same genus. () The "cyclic" wax were the esters consisting of fatty acids (_<10>-_<32>) and unusual cyclic alcohols (diterpenes and sesterterpenes). Structures and stereochemistry of nine new sesterterpenes will be discussed on the basis of spectroscopic and chemical methods: Cericerol-I (1), cericerol-II (2), 13-methoxy cericerene (3), 13-ethoxy cericerene (4), α-cericerol-I (5), cericeroic acid (), 18-dihydro-19-ol cericeroic acid (), cericera-2(),(Z),10(),15(), 18-pentene-25-acid (), cericera-2(),(Z),10(),15(), 18-pentene-24-acid (), and cericerene-15,24-diol (10). Possibility of the configurational isomers for the structures ()and () at the position -24 and -25 are still remained to be elucidated. Bridged hydrocarbon (16) which was obtained by acid treatment of tosylate of cericerol-I (1) indicated the crown shape (A) for (1).

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