The acetone extracts from three samples of the hepatopancreas of the poisonous scallops obtained on the Okhotsk Coast of Hokkaido Island were fractionated into two parts, hexane soluble fraction (fraction H) and % aqueous ethanol soluble fraction (fraction ) by partition to two layers. The majortoxic components in the mouse assay of “diarrheic shellfish toxin” by intra-peritoneal injection were found to be free unsaturated fatty acids showed the following toxicity in MU per g, 18:1 n- 35, 18:2 n- , 18:3 n-3 167, 18:4 n-3 , 20: n-3 167, and : n-3 , respectively. Toxicity of the fraction Hin MUper g was much lower than that of the fraction . However, the toxicity of the fraction H per 1 g of the hepatopancreas was about twice that of the fraction , since the fraction Hwas much more abundant than the fraction in the hepatopancreas. The method for the assay of the diarrhetic shellfish toxin must be reexamined by considering the toxic effect of the free unsaturated fatty acids.

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This paper outlines a mathematical description of the stress dilatancy behaviour of granular materials which accounts for stress level and void ratio dependencies. The consideration of these aspects has important implications in the modelling of granular material behaviour. In fact, granular material mechanical response is largely dominated by the evolution of dilatancy, fabric and void ratio histories. The starting point in this study is the well established Rowe's theory which is revisited and ultimately modified by introducing a factor linked to governing state parameters in order to describe the complete behaviour of granular materials during deformation. Numerical simulations of triaxial tests on granular materials at different void ratios and stress levels are herein presented to illustrate the model.

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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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A full account is given of the chemical behavior observed for 7, -dialkyladeninium salts (16). On treatment with boiling 1N aqueous NaOH for 60min, 16a, b, , (X=I), 16 (X=Br), and 16f (X=ClO₄) rearranged to isomeric , 7-dialkyladenines (21a-f) in 50-91% yields. Treatment of the salts with 0.N aqueous Na₂CO₃ at room temperature for 30-90min or with Amberlite CG-400 (OH^-) in H₂O at room temperature gave the ring-opened derivatives a-f (in the trans-formamide form) in 56-% yields, and rate constants for the ring-opening reactions of 16a, b, -g (X=ClO₄) and 16 (X=Br) leading to a-g were determined in H₂O at pH .84 and ionic strength 0.50 at 25°. Cyclization of a with NaH in AcNMe₂ at room temperature or with boiling 1N aqueous NaOH produced 21a in 84% or 72% yield, respectively.In solution, the trans-formamides seemed to transform slowly into the cis-formamides 23, attaining equilibria. The existence of such an equilibrium in or Me₂SO- at 25° or in H₂O at pH .84 and ionic strength 0.50 at 25° was kinetically confirmed in the case of a, and the mechanism of the rearrangement of 16 to 21 through is discussed on the basis of the above kinetic results and Deslongchamps' theory of stereoelectronic control. On treatment with NaBH₄ in MeOH at room temperature, 16a (X=I) furnished the 7, 8-dihydro derivative 28 (84% yield), which slowly decomposed in H₂O at 60° to give a in 49% yield.The 7, -dialkyladeninium salts (16) were found to be obtainable from N'-alkoxy-1-alkyl--formamidoimidazole-4-carboxamidines () through an alternative synthetic route : Alkylations of with alkyl halides in HCONMe₂ in the absence of base, followed by hydrogenolysis of the N'-alkoxy group and cyclizatio (or vice versa) produced 16 in acceptable yields. In order to interpret the proton nuclear magnetic resonance spectrum of a, the 2-deuterated species 26 was also synthesized from 24 via 25 and 27.

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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), () X(), Y (7) and Z (8) were confirmed by extensive 1 and 2 NMR spectral data and X-ray analysis. Blazeispirols A (1), B (2), (3), (4) and () were des-A-ergostane type compounds having spiroacetal structure as a side chain. Blazeispirols X () and Y (7) were determined to be (20S, S, 23R, 24S)-1 (10→) abeo-14β, :, 25-diepoxyergosta-,7,,11-tetraene-3α,23-diol and (20S, S, 23R, 24S)-14β,:,25-diepoxy-,23-dihydroxyergosta-4,7,11-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, - 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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The advantages and disadvantages of using a back analysis of slope failures to evaluate soil shear strength are discussed. A methodology is presented herein that allows the implied level of reliability associated with soil shear strength parameters back calculated from slope failures to be estimated. A reliability approach is also used to estimate the probability of failure for a given limit equilibrium slope stability method, design factor of safety, and combination of back calculated Mohr-Coulomb shear strength parameters, ' and φ'. The methodology is illustrated using 39 landslides in the Orinda Formation in the San Francisco Bay area. The impact of additional case histories in the same geologic setting, i.., a larger data set, on the required design factor of safety for a given probability of failure is also investigated.

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The present paper aims at developing a simplified model for a stress-strain relationship at small strains up to an initial yielding of homogeneous saturated frozen sand. The modelling of elastic moduli for an ice-sand mixture as a composite geomaterial is first introduced based on previous studies, where a saturated frozen sand is treated as the icesand mixture. The applicability of modelling the elastic moduli under constant temperature is then discussed from the theoretical and experimental points of view. In addition, the hyperbolic stress-strain modelling of saturated frozen sand at small strain is presented. The effect of the volume fraction of sand, stiffness of sand inclusion and temperature changes on the elastic moduli and the stress-strain behaviour up to about 1-2% axial strain, which is defined as an upper yield stress, are investigated through the model, whose applicability is verified in comparison with the experimental data.

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Ten furostanol saponins were isolated as five pairs of 25R and 25S epimers from the fresh rhizomes of Polygonatum kingianum. Seven of them were identified as new compounds, (25S)-kingianoside (2), (25S)-kingiano-side (4), (25R,)-hydroxylwattinoside (), kingianoside (7), (25S)-kingianoside (8), kingianoside F () and (25S)-kingianoside F (10), together with three known saponins, kingianoside (1), kingianoside (3), and -hydroxylwattinoside (). The structures of the new saponins were determinded by detailed analysis of their 1 and 2 NMR spectra, and by comparison of the spectral data with those reported.

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Four edible mushrooms, Panellus serotinus, Lepista nuda, Tricholoma matsutake and Naematoloma sublateritium, have been investigated chemically. Two new sterols, , -epidioxy-()-ergosta-7, -diene-3β, -diol (1) and , -epidioxy-()-ergosta-7, -diene-3β, -diol (2), have been isolated from Panellus serotinus. Compound 2 was also isolated from Lepista nuda. A new sterol, 3β, , , 14β-tetrahydroxy-()-ergosta-7, -dien--one (3), and compound 2 have been isolated from Tricholoma matsutake. Three new triterpenoids, sublateriols A- (4-), have been isolated from Naematoloma sublateritium. The structures of the new compounds were elucidated on the basis of their spectral data.

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The area investigated is located at longitude 66°30′W and latitude 48°N, on the northern shore of Chaleur Bay. Some 124 specimens (46 samples) were collected from sites in the following geological formations: La Garde (10 samples, late Early to early Middle Devonian), Pirate Cove (11 samples, early Middle Devonian), Fleurant (15 samples, early Late Devonian) and Escuminac (10 samples, early Late Devonian). These formations are composed of conglomerates, silty and calcareous sandstones deposited in a continental environment. The Upper Devonian geological units are amongst a few found in Canada to the east of Alberta. The main goal of this study is a better definition of the Apparent Polar Wander Path of the Appalachians of North America. This study allowed the identification of geological formations favourable to paleomagnetic sampling. Remanent magnetizations and magnetic susceptibilities were measured; both alternating field and thermal demagnetizations were carried out. After demagnetization, 4 components (A, B, and ) were isolated and several components were found in each formation. Fold and conglomerate tests were performed; the first is significantly negative except for component B and the second is positive in the Fleurant Formation. The mean direction of the components is: 156°, +31° for A, 52°, -46° for B, 167°, -21° for and 223°, +25° for . The corresponding paleopoles are °N 141°, °S 77°, 51°N 137° and 17°N °. Based on the fold test, degree of alteration and unblocking temperatures, it was found that components A, and are secondary. Component B is either primary or secondary. The relative age of acquisition of magnetization is the following: B>

D

>A>. The paleolatitudes vary from 17°S to 10°N going from A to B (tilt corrected), to and to . The results are discussed in relation to the Devonian Apparent Polar Wander Path of North America.

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The dual stage actuation (DSA) is one of the most attractive methods for increasing the track density of hard disk drives (HDDs). We have developed a φ-shaped actuated suspension as a fine actuator for a DSA system. The developed suspension's main resonance frequency was higher than kHz, its generated displacement was larger that 1- m at an applied voltage of 30 V and its shock resistance was greater than 3000 G. Flying-height variance caused by DSA driving (+/- V) was less than 1.3 % of nominal flying-height. The decrease of displacement was almost constant, less than % after 1 driving-cycles under heavy conditions (+/- 30V at 100℃, +/- 30V at ℃ and % humidity). Based on these data, we concluded that our actuated suspension can maintain a stable flying-height during its operation and its lifetime is as long as other actuators for HDDs.

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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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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-)(7-10) 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 (), cericeroic acid (), 18-dihydro-19-ol cericeroic acid (7), cericera-2(),(Z),10(),15(), 18-pentene-25-acid (8), cericera-2(),(Z),10(),15(), 18-pentene-24-acid (), and cericerene-15,24-diol (10). Possibility of the configurational isomers for the structures (8)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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Eight new sterols, , 8α-epidioxy-(, 24R)-23-methylergosta-, -dien-3β-ol (1), 3β, , -trihydroxy-(, 24R)-23-methylergosta-7, -dien--one (2), 3β, , -trihydroxy-(24S)-ergost-7-en--one (3), 3β, , , 14α-tetrahydroxy-(, 24R)-ergosta-7, -dien--one (4), (, 24R)-ergosta-7, -diene-3β, , , -tetrol (), , -epidioxy-3β-hydroxy-(, 24R)-ergosta-7, -dien--one (), , -epidioxy-3β-hydroxy-(24S)-ergost-7-en--one (7) and , -epoxy-(, 24R)-ergosta-8, -diene-3β, 7β, 14α-triol (8), have been isolated from five edible mushrooms, Lentinus edodes, Flammulina velutipes, Hypsizigus marmoreus, Pleurotus ostreatus and Pholiota nameko together with fifteen known ones (-23), of which two (16 and 17) are reported for the first time from a fungal source. The structures of these new compounds were elucidated on the basis of their spectral data.

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