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 Beckmann rearrangement of aliphatic ketone oximes, R(CHs)C=NOH (R=Et (1); n-Pr (); iso-Pr (3); iso-Bu (4)), with polyphosphoric acid (PPA), polyphosphate ester (PPE), and ester of phosphoric acid ( P-5 R) was carried out and migratory ratios ((a)/(b) in eq. (1)) were determined, The results are shown in Fig.1, , and 3, respectively.
In Fig.1 and , the migratory ratios decrease with reaction time and nearly approach to the ratios of anti-alkyl form/syn-alkylform in benzene(A1) or DMSO(A)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 A. 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 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 P-5 R.

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Two new polyacetylene compounds (4, , 12)-1-acetoxy-3-isovaleryloxytetradeca-4, , 12-trien-, 10-diyn-14-ol (B), 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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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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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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The rate dependent nature of liquefied sand was investigated by laboratory shear tests. Since previous experience has revealed the many difficulties inherent in maintaining the state of liquefaction of a sandy specimen, new measures were attempted. The test results indicate that the measured shear stress consists of frictional and rate dependent components, and a viscosity coefficient was assessed from the latter component. The measured viscosity varies with the rate of strain as well as the magnitude of strain itself. A similar test on a dry specimen revealed less viscosity and implied that a major part of rate dependency comes from the behavior of pore liquid in the case of water-saturated sand. It was interesting, moreover, that sand with fines was of less viscosity. Finally, a numerical analysis was conducted on a real liquefaction-induced ground deformation and the results were consistent with the observation.

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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, c' 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 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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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-% 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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The characteristic mechanical activities of the smooth muscles found in all organs of the body are highly variable and depend mainly on the spatial arrangement of the muscle cells and the stroma: mass, orientation, relationships, links, constraints, which are deployed in various configurations. These structural features are examined here for their mechanical relevance, in light and electron microscopic views of several muscles of viscera and blood vessels, in a selection of mammalian species. Smooth muscles are incompressible and therefore maintain constant volume. They do not have available space and any movement of a part requires displacement of another part. Most of them have no terminations or points of attachment, and in hollow organs such as intestines, blood vessels and uro-genital tract they usually form structures closed onto themselves, such as rings or bag-like containers In these situations, changes in the size of the lumen is achieved very efficiently by a concentric inward enlargement that accompanies muscle contraction. The longitudinal arrangement of collagen blocks an elongation of small blood vessels upon contraction, further enhancing the efficiency of lumen reduction. In other muscles, links between layers and special arrangements of the stroma allow both shortening and elongation of a tubular organ to occur. The mechanics of smooth muscles has many characteristic features (some unique, some shared with those of hydrostats, some at variance with other muscles) and histological data are a contribution to our understanding of these properties.

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All the cells of rat detrusor muscle fall into one of five ultrastructural types: muscle cells, fibroblasts, axons and glia, and vascular cells (endothelial cells and pericytes). The tissue is ~79% cellular and 21% non-cellular. Muscle cells occupy 72%, nerves ~4% (1/3 axons,

/3 glia), and fibroblast >3% of space. Muscle cells (up to µm across and ~600 µm long, packed to almost 100,000 per ) have surface-to-volume ratio of .4 /µm³ ~93% of cell volume is contractile apparatus, 3.1% mitochondria and .5% nucleus. Cell profiles are irregular but sectional area decreases regularly towards either end of the cell. Muscle cells are gathered into bundles (the mechanical units of detrusor), variable in length and size, but of constant width. The musculature is highly compact (without fascia or capsule) with smooth outer surfaces and extensive association and adhesion between its cells. Among many types of intercellular contact and junction, digitations are very common, each muscle cell issuing minute finger-like processes that abut on adjacent cells. Sealed apposition are wide areas of specialized contact, possibly forming a chamber between two muscle cells, distinct from the extracellular space at large (stromal space). The innervation is very dense, virtually all intramuscular axons being varicose (including afferent ones). There are identifiable neuro-muscular junctions on each muscle cell, often several junctions on a single cell. There are also unattached terminals. Fibroblasts (involved in the production of collagen), ~1% of the total number of cells, do not make specialized contacts.

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Earth pressures are generated on the abutment wall of an integral bridge as a result of thermal expansion of the bridge deck. This provides an example of soil : structure interaction where a rational result can only be obtained if the relative stiffiness of the fill and the structure is taken into account. The problem must be understood and analysed as a whole. A numerical case study is described in which analyses of a typical integral bridge are used to show that, for the flexible abutment wall being considered, the development of earth pressure is primarily controlled by the stiffness of the fill and is hardly influenced by its strength. Comparisons are given between computed earth pressures and those proposed by design guides. The fill is described as an elastic-Mohr Coulomb perfectly plastic material. Typical stress paths for elements behind the wall indicate that the nature of the loading is dominated by compression rather than shearing. The selection of stiffiness properties-for which very little reliable information will usually be available-is discussed and a possible range of values is proposed.

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In this paper, constitutive relations for expressing the inelastic behavior of sandy ground expected at the time of a strong earthquake are proposed. These constitutive relations are formulated by a yield function in terms of effective stress ratio and by a plastic potential function which is derived from the stress ratio-plastic strain incremental ratio defined as a function of accumulated volumetric strain. These constitutive relations employ Sekiguchi and Ohta's stress parameter to take account of the effects of rotation of principal stress axis on the deformation characteristics of sand. The Masing rule is modified in such a way that it can be used in the multi-dimensional stress field, and employed in the hardening function in order to express a hysteretic damping. Material constants contained in the proposed constitutive relations can be easily determined by the mechanical tests which are normally conducted in laboratory. The comparison between predicted behaviors by the constitutive relations and results of undrained cyclic shear tests shows that the dynamic strength-deformation characteristics of sand in a wide range of density can be simulated satisfactorily.

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カミクラゲSpirocondon saltatrixはキュウリのにおい成分である（

）--nonenalと（

E

,Z）-,-nonadienal を持つため強烈なキュウリのにおいがする．これらの物質は一般的な多価不飽和脂肪酸から酵素反応を経て生じると予想される．キュウリ様におい物質はカミクラゲにとってのケミカルシグナルや防御物質など，何らかの生物学的な機能を持つ可能性がある．

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