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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Two new partially saturated tricyclic ring systems, , a, , , 9, 10, 10a, 11-octahydro-11-oxodibenz [, ] oxepins (3a and 3), and -thiepins (4a and 4) were synthesized. Compounds 4a and 4 were desulfurized to give a pair of isomeric -methylbenzoylcyclohexanes (10a and 10). Deuterated 4a and 4 (11a and 11) were prepared starting from butadiene- (12). The stereochemical features of 3a (trans), 3 (cis), 4a (trans) and 4 (cis) are compared with those of 10a, 10, 11a and 11 on the basis of proton nuclear magnetic resonance data.

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Using the so-called pseudo-static method, a stability analysis was made for the mountain slide that took place at Mitake-iriya village at the time of the Izu-Ohshima-Kinkai earthquake of January 14, 1978. Undisturbed samples of volcanic clay were obtained in blocks from the exposed surface of the deposit identified to have been the sliding surface. The partially saturated clay samples were tested under consolidated undrained conditions using the triaxial test equipment. Dynamic axial stresses with irregular time histories were applied to the specimens in combination with statically sustained axial stresses to determine the soil strength under the conditions simulating in-situ states of stress during the earthquake. The results of the tests were expressed in terms of the Mohr-Coulomb type failure criterion which showed that, while the angle of internal friction remained almost unchanged, the cohesion component in irregular loading increased above values obtained in the static loading. Using the strength parameters thus determined, a pseudo-static analysis was made to check the stability of the soil masses that had actually slid during the 1978 earthquake. The maximum horizontal acceleration required to cause the slide was computed. The computed accelerations were shown to cover a range between 400 and 500 gals which is consistent with the range estimated by other investigators on the basis of overturning of tombstones in the vicinity of the slide area.

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We screened the differentiation-inducing activities of 39 mushroom extracts from Akita prefecture, Japan, on the mouse osteoblastic cell line, MC3T3-1. Sixteen phosphate buffered saline (PBS), boiled PBS, 14 ethanol and 12 methanol extracts induced alkaline phosphatase (ALP) activities, an indicator of MC3T3-1 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-3β,5α,-triol (1). 1 induced ALP activities of MC3T3-1 cells and promoted cell proliferation. To investigate the relationships between the chemical structure and differentiation-inducing activity of the compound, ALP-inducing activities of MC3T3-1 cells by 1, ergosterol (), ergocalciferol (3), cholesta-3β,5α,-triol (4), -dehydrocholesterol (5) and cholecalciferol () were tested. The enzyme activities of MC3T3-1 cells were increased 3.0-fold by 10 μM 1 and .4-fold by 10 μM 4. However, , 3, 5 and did not induce MC3T3-1 cell ALP activity at 0.1—10 μM. These results suggested that the OH groups at C-5 and/or C- of 1 and 4 played an important role in their differentiation-inducing activities on MC3T3-1 cells. Furthermore, 1 suppressed induction of MC3T3-1 cell apoptosis by serum starvation.

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The gamma-ray spectrum and the conversion-electron spectrum are measured in the decay of the Tb¹⁵² activity. The L-subshell electron lines of the 586. keV +→2₁⁺ transition are separated by the ion-free beta-ray spectrometer. The M1- mixing ratio, , and the dimensionless ratio X of 0- mixing of the 586. keV transition are obtained to be ≤0.16 and 0.034≤X≤0.038, respectively. The branching ratio (; +→0_g⁺): (; +→2₁⁺): (; +→0₁⁺) is determined to be 0.023 : 1.0 : 5..

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Six sorts of aluminium-silicon JIS commercial cast alloys, i.. AC, ACBT, AC3, AC4, AC4AT and AC4, were examined on drill-machinabilities in regard of drilling resistance, accuracy of drilled holes, deposits on the drill face, chip treatment and others. The results obtained were summarized as follows:
(1) In the case of F-materials (as-cast), the drilling resistance and time were smaller in copper-containing materials, i.. and 4, and were larger in 4, especially 3. And the drilling resistance and time of T-materials (heat-treated) were larger than those of F-materials.
() The drilling temperature was lower in 4AT than in the other materials, but the temperatures were about 100∼120°C as a whole and posed no serious problem.
(3) In the case of F-materials, the accuracies of drilled holes, i.. enlargement of the hole diameter, roundness of the hole figure and surface roughness of the drilled hole in 4 and 3 were inferior to those in and 4, and the roundness of the hole figure and the surface roughness of holes in T-materials were better than those in F-materials.
(4) In the case of F-materials, the deposits, such as a cohesive large built-up edge, which deteriorate the accuracy of a drilled hole, were observed on the drill face. This phenomenon was more remarkable in 4, especially 3 than in and 4. And the deposits in T-materials were less cohesive and smaller than those in F-materials.
(5) There were no difficulties in chip formation regardless of the chip treatment.

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11-Amino-, a, , , 9, 10, 10a, 11-octahydrodibebenzo[, ]thiepines (a-d) and -oxepines (a-d) were synthesized by the Leuckart reaction of , a, , , 9, 10, 10a, 11-octahydro-11-oxodibenzo[, ]thiepines (1a, )and -oxepines (a, ) followed by hydrolysis of the reaction products 4a-d and 5a-d, 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) and , trans(a-H, 10a-H)-trans(10a-H, 11a-H)c and c, and trans(a-H, 10a-H)-cis(10a-H, 11-H) d and d, 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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Among the rivers damaged by the earthquake, two most severely damaged along the Yodo-gawa River are described. In the left levee, the settlement exceeded m for a length of 1.4 km, with a maximum settlement of 3 m. Sand boils were observed extensively on the ground surface near the damaged dikes. Holocene sandy soil with an SPT N-value of 10 or less existed in the upper part of the subsoil profile. These facts indicate that liquefaction of the soil was the major cause of the embankment damage. The cyclic stress ratio required to cause liquefaction was 0.30 as determined from cyclic triaxial tests on undisturbed samples.

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By employing an undrained cyclic loading ring-shear apparatus, a series of tests to reproduce the dynamic behavior of the Nikawa landslide induced by the January 17, 1995 Hyogoken-Nambu earthquake, is conducted. The test sample is Osaka-group coarse sandy soil taken from the landslide. The initial stress condition acting on a soil element in the sliding surface is applied to the sample. Based on the seismic records monitored at the JR Takarazuka Station, the input seismic wave is synthesized to reproduce the seismic stress acting on the sliding surface. The test results show that the soil failed due to the dynamic loading of the earthquake. The most important results are the excess pore water pressure generation and the acceleration of shear displacement continuing after the main shock. Combined with the grain crushing at the shear zone and the volume reduction in the drained constant-speed ring-shear test, the mechanism of this landslide is interpreted as, shear displacement causing grain crushing in the shear zone and volume reduction, and then resulting in a localized liquefaction phenomenon, "sliding-surface liquefaction". This geotechnical simulation test provides a reasonable interpretation of this highly mobile landslide.

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The gamma-ray spectrum and the conversion-electron spectrum are measured in the decay of the ^116mIn activity. Directional correlations are also measured for 818–1293 and 1097–1293 keV cascades. The M1- mixing ratio δ, and the 0- mixing ratio μ_k are obtained for 818. keV +→2₁⁺ transition to be δ=1.52−

0.22

+0.26, and μ_k≤

6

.1×10⁻⁴ respectively. The

E

2

branching ratio

B

(

E

2

;

2₂

+→0_g⁺):

B

(

E

2

;

2₂

+→2₁⁺):

B

(

E

2

;

2₂

+→0₁⁺) is determined to be 0.0158:1.0:5.86.

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When a mudflow moves down a slope, the gravity induced shear stress, τ, is opposed by the combined effect of the undrained shear strength, c_u, of the mud, and its viscosity, η, which is associated with the velocity gradient in the mudflow, dv/dy. In equation form this can be expressed as : τ= c_u+η(dv/dy). The resistance provided by the mud involves the contribution of both c_u and η. For an understanding of the mobilization mechanics of mudflows, one needs then these two parameters. This study describes two methods that can be used to determine these parameters. The c_u of the muds is measured using a cylinder-strength meter devise. The technique associated with this devise consists in lowering a cylinder of known dimension and weight into a mud sample, measuring the depth of penetration of the cylinder into the mud, and calculating the strength, c_u, of the mud required to support the solid cylinder at that depth. The c_u of the mud is calculated using Sokolovski's theory designed to calculate the indentation pressures developed by a Tresca plastic when a cylinder penetrates it. The determination of the viscosity, η, of the mud is obtained from either the velocity measurements of the free surface of the mudflow, or from the difference between the velocity of the free surface of the mudflow and its velocity at the interface between the mudflow and the surface on which it moves. The viscosity η is obtained from a relationship that relates these velocities with η.

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Using two direct introduction methods, DNA synthesis or cell proliferation activities of three purified proteins from . coli, namely, human papillomavirus (HPV) proteins of type 16, a mutant type 16 (24 C-G) (transformation defective) and type , were measured in mouse fibroblast, C127 cells. By a microinjection method, the order of the cell mitotic indexes for the three proteins as determined by 5-bromo-'-deoxy-uridine (BrdU) staining was type 16, and 16 (24 C-G). By the osmotic shock method, the ³H-TdR incorporation and coloration by (3-carboxymethoxy phenyl)--(4-sulfophenyl)-H-tetolazorium (MTS) for the three proteins correlated with the pRb binding and focus forming activities previously reported (hunger et al. 1991). These results indicate that the simple osmotic shock method for direct protein introduction may be generally useful for transformation assays of oncoproteins.

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The objective of this article is to propose and evaluate a sliding-block model to deal with very large displacements of slopes when a horizontal earthquake is applied. The slip surface consists of two inclinations on which full shear resistance is mobilized. Internal shearing exists along a sub-plane that intersects the angle between the two sub-planes that form the external slip surface. The ratio of the distance moved along the two external sub-planes depends on the inclination of the internal sub-plane. If there is a water table line, undrained conditions are assumed during motion and total stress analysis is performed. The governing equations of motion are formulated, analytical solutions are obtained for some cases, and back-analysis of four well-documented slides is performed.

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This paper is concerned with an extension of a rotational limit equilibrium method for determining the permanent displacements of slopes under seismic excitation. In the proposed procedure, the sliding mass is treated as a rigid rotating body defined by a log spiral trace. Permanent displacements are obtained by double-integration of the equation of motion in a manner similar to Newmark's translational sliding block method. The seismic slope stability analysis is based on the rotational (variational) limit equilibrium approach. This stability analysis was verified with dynamic experimental results obtained from centrifuge model testing. A series of parametric studies was conducted on"unstable"slopes, investigating the effects of soil properties and characteristics of excitation on the magnitude of permanent displacements. The higher the frictional angle, the smaller the permanent displacement of the slope is. Low excitation frequency yields larger slope displacement if the excitation is extended for the same time period of time. The effect of frequency becomes less distinct when a larger value of yield seismic coefficient is used. The proposed procedures produce a rational criterion to evaluate the seismic performance of simple slopes. This criterion is based on permanent displacement limit rather than factor of safety alone.

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Based on the assumption that an inward- or outward-directed flow perpendicular to a slope exists, this paper describes an experiment and test results. The results are compared with both traditional continuum and single-grain theories presented for the relationship between hydraulic gradient and slope angle. For the case of outward flow, the continuum theory governs the failure mechanism of the Shirasu talus deposit. The single-grain theory controls the failure process for inward flow.

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An analytical model is presented for steady-state lateral response of earthfill and rockfill dams in canyons subjected to a steady train of harmonic SH waves incident at an arbitrary angle θ. The dam is idealized as a -dimensional shear beam with a triangular cross-section, while the canyon is considered rectangular and consisting of elastic rock. A parametric study is undertaken to investigate the influence on the steady-state response of (a) the angle of incidence θ of the incoming waves, () the impedance ratio and (c) the canyon narrowness. It is shown that the acceleration amplification is considerably less for a dam built in flexible canyon than for a dam in a rigid canyon and, hence, the effect of radiation damping may be very important. For obliquely incident waves travelling from the left to the right, the response of the dam depends mainly on the interference of the waves transmitted through the base and the left boundary, leading to a maximum response at a θ about 30°-35°. For very long dams subjected to high frequency obliquely incident waves, it is found that there is no amplification of the motion by the dam. For low-frequency excitation, the response of the dam shows little variation along the crest and approaches the response of the elastic half-space. The results are in agreement with published results for the response of alluvial valleys subjected to incident SH waves.

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Two new polyacetylene compounds (4, , 12)-1-acetoxy-3-isovaleryloxytetradeca-4, , 12-trien-, 10-diyn-14-ol (), and (4, , 12)-1-acetoxy-3-(-methylbutyryloxy)tetradeca-4, , 12-trien-, 10-diyn-14-ol (C) have been isolated along with (4, , 12)-1-acetoxy-3-senecioyloxytetradeca-4, , 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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