Two new polyacetylene compounds (, , 12)--acetoxy--isovaleryloxytetradeca-, , 12-trien-, 10-diyn-14-ol (), and (, , 12)--acetoxy--(2-methylbutyryloxy)tetradeca-, , 12-trien-, 10-diyn-14-ol (C) have been isolated along with (, , 12)--acetoxy--senecioyloxytetradeca-, , 12-trien-, 10-diyn-14-ol (A) from Atractylodes Rhizome (Karabyakujutu). The structures of these compounds were determined on the basis of their spectral data.

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It has been shown after mathematical and mechanical investigation that Limit Equilibrium Method (LEM) can be considered as a method to obtain the necessary condition of Slip Line Method (SLM), and that the solution can be obtained under the condition that F_s= and ∂F_s/∂θ=O, where F_s is the safety factor and θ is the inclination of the plane on which the safety factor is defined. Next, the generalized LEM (GLEM) is proposed, dealing with the following points : () Triangular or quadrangular blocks can be treated; (2) Safety factors are defined also on interblock planes; and () All types of plastic problems, slope stability, bearing capacity, and earth pressure are identically formulated. Two situations regarding treatment of the moment equilibrium condition are discussed. GLEM is applied to well-known problems. The results agree well with those obtained by theoretical methods. GLEM can be used to obtain the distribution of earth pressure or bearing capacity. GLEM, Iike ordinary LEM, is very effective for the practical problems, but GLEM is more theoretical and it can result in more accurate solutions.

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The possibility of attenuation of microseismic waves due to the presence of an upward folding of the ocean bottom into the liquid is discussed in this paper. The upward folding of the ocean bottom has been idealized by means of an irregularity in the form of a rectangle intruding into the liquid and the evaluation of the displacement component at any point of the solid medium has been carried out in two stages. First, the change in the incident mode of the surface wave due to the presence of the rectangular irregularity has been determined, and second, the subsequent change of the resulting displacement components due to the termination of the liquid layer and the step change in elevation of the solid medium at the continental margin has been discovered. Finally, numerical calculation has been made to determine the attenuation of the microseismic waves of different periods due to the presence of the rectangular irregularity at the ocean bottom.

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We screened the differentiation-inducing activities of 39 mushroom extracts from Akita prefecture, Japan, on the mouse osteoblastic cell line, MCT-. Sixteen phosphate buffered saline (PBS), boiled PBS, 14 ethanol and 12 methanol extracts induced alkaline phosphatase (ALP) activities, an indicator of MCT- cell differentiation. The enzyme activities were markedly induced by extracts of Tricholoma auratum, and we isolated the active compound from methanol extracts of this mushroom. Physical data for the isolated active compound were identical to those for (,24R)-ergosta-,-diene-,,-triol (). induced ALP activities of MCT- cells and promoted cell proliferation. To investigate the relationships between the chemical structure and differentiation-inducing activity of the compound, ALP-inducing activities of MCT- cells by , ergosterol (2), ergocalciferol (), cholesta-,,-triol (), -dehydrocholesterol () and cholecalciferol () were tested. The enzyme activities of MCT- cells were increased .0-fold by 10 μM and 2.-fold by 10 μM . However, 2, , and did not induce MCT- cell ALP activity at 0.—10 μM. These results suggested that the OH groups at C- and/or C- of and played an important role in their differentiation-inducing activities on MCT- cells. Furthermore, suppressed induction of MCT- cell apoptosis by serum starvation.

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A method for analyzing the uncertainties involving the use of empirical relationships in design is developed. It is applied to evaluate the reliability of the relationship s_u(mobilized)=(measured), whereby the pertinent uncertainties are analyzed using extensive laboratory and field observed data. On the average, the relationship s_u(mobilized)= (measured) is unbiased and the error implicit in the relationship is about 15%. When cone values are used to infer s'_p, additional uncertainties on the mobilized undrained strength will incur resulting mainly from the calibration uncertainty between σ'_p and the cone values. Alternatively, vane tests may be performed to infer the mobilized strength using Bjerrum correction factor. Results show that uncertainty level associated with using the vane tests is smaller than that using the cone values, provided that similar scatter is observed between measured vane and cone values at a given site. However, prediction of the mobilized strength is even more accurate if direct measurements can be made on the preconsolidation pressure. The proposed probabilistic method also assesses the benefit of additional tests besides comparing the accuracy of using various soil parameters for predicting mobilized undrained strength. Such information is essential for planning cost-effective site characterization program.

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The pseudo-static analysis has been used in engineering practice to simplify the computation of the upper limit of a slope under seismic load. In this paper, the upper bound technique of limit analysis of perfect plasticity is used to determine the bearing capacity of a foundation near a down-hill slope. In this analysis (Chen et al., 1969; Chen, 1975), a logarithmic spiral rapture (Abdul-Baki et al., 1970; Sawada et al., 1984) is assumed to start at an edge of the loaded area far from the slope. A landslide is assumed to be of rigid body type with the inertia force acted at its center of gravity. The collapse state is reached when the rate of kinematic energy of the landslide together with the load is equal to the rate of dissipation of internal energy along the sliding surface. This energy balance leads to the equation of ultimate load with several parameters. The optimized numerical rcsults with respect to these parameters are compared with those by Kotter's method (Yamaguchi, 1959) and those obtained by the slice method.

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This paper presents reinforcing mechanisms and a method for analyzing reinforced earth structures. The reinforcing mechanism presented is divided into two stages, a fixed slip surface and an arbitrarily selected slip surface. The mechanism is studied through direct shear tests and plane strain compression tests including some geotextiles. The reinforcing materials considered in this paper only have tensile strength. The authors have already proposed a method called Generalized Limit Equilibrium Method (GLEM) for analyzing stability problems. The validity of the method has already been shown in previously published papers. In this paper, the method is extended to carry out a stability analysis for reinforced earth structures. Finally, large scale model tests for the bearing capacity of foundations on reinforced slopes were carried out to investigate the validity of the proposed reinforcing mechanism and the analytical method. Through comparisons of observations of experiments and results of the analytical method, the validity of the present work is demonstrated.

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This paper focuses on an extension of the log-spiral analysis of bearing capacity that has been presented in the authors' previous work for strip foundations placed on the level ground, to those on the top of slopes. Comparisons are made with other analytical and experimental results to examine applicability of the method to practical problems. It is revealed that the log-spiral analysis somewhat overestimates bearing capacity values as compared to other solutions, the errors involved being around 20 percent at maximum and varying sensitively to the angle of internal friction and slope inclination. Also noticed is a relatively good correspondence with experimental results, especially with model tests on clay (φ=0), on both the ultimate bearing capacity and the shape of sliding surfaces.

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The saponin fraction from the seeds of the tea plant [Camellia sinensis (L.) O. KUNTZE (Theaceae)] was found to exhibit potent protective effects on ethanol- and indomethacin-induced gastric mucosal lesions in rats. Five new triterpene saponins, theasaponins (), (2), (), (), and (), were isolated together with 11 known saponins from the saponin fraction. The chemical structures of — were elucidated on the basis of chemical and physicochemical evidence. Among the isolated saponins, theasaponins (), (), and () and assamsaponin C (10) showed an inhibitory effect on ethanol-induced gastric mucosal lesions at a dose of .0 mg/kg, p.o. and their activities were stronger than that of omeplazole. With regard to the structure–activity relationships of theasaponins, the following structural requirements for a protective effect on ethanol-induced gastric lesions were suggested; ) the 21- and/or -acyl groups are essential for the activity, 2) acetylation of the 16-hydroxyl group reduce the activity.

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ラットに

3H

-CU-

83

(S)を25μg/kgで静脈内あるいは経口投与し，血液中濃度および尿糞中排泄を検討した．
静脈内投与後の血液中濃度推移は投与後

5

分より上昇し，投与後45分に25.74ng eq./mlのC_maxを示し，それ以後

t₁

/2

3

.05時間と

t₁

/2 33.09時間の二相で減少した．投与後72時間までのAUCは135.42ng eq.·hr/mlであった．
経口投与では，投与後

3

時間でC_max

4

.10ng eq./mlに達し，以後

t₁

/2α

4

.46時間と

t₁

/2β 26.

83

時間の二相で減少した．投与後72時間までのAUCは48.62ng eq.·hr/mlであった．
静脈内投与と経口投与のいずれの場合も，尿および糞中への放射能の排泄は，投与後48時間でほぼ終了した．静脈内投与では，投与後72時間までに投与量の30.52%が尿中に，60.42%が糞中に排泄された．経口投与では，同じく72時間までに40.34%が尿中に，69.24%が糞中に排泄された．

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