A sample of [³H] tobrarnycin (5, 000 Ci/Mole) has been synthetized and incubated with
the bacterial ribosome and its subunits. The results obtained show that this antibiotic has
two types of binding sites. The primary one is probably responsible for the inhibition of
protein synthesis whereas the secondary one is probably related to the misreading and reading
tiirough of the messenger RNA.

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The Gujarat earthquake in India occurred in January, 2001, and caused significant damage in the province of Gujarat. The Japanese Geotechnical Society sent a small reconnaissance team to the damaged region after the quake. The present text presents the report from this activity. The major attention of the team was focused on geotechnical aspects of the damage which were related to earthfill dams and harbor land fills. It was found that a significant portion of damage was concentrated in fills resting on soft natural soils. Swedish weight soundings which were conducted at two places demonstrated the existence of such a soft subsoil. From this, it was concluded that amplification of earthquake shaking as well as the permanent deformation in the soft foundation soil induced such kinds of damage as subsidence, cracking, and lateral spreading in overlying artificial fills. For the better seismic resistance of those affected fills during future earthquakes, the improvement of soft subsoil seems essential.

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The boundary element method expanded in frequency domains is presented to analyze the dynamic interaction between an embedded flexible rectangular foundation and soil with consideration of the obliquely incident waves. Numerical results describing the influence of the flexibility of the foundation on the dynamic responses of the foundation due to obliquely incident waves indicate that the flexibility of actual foundations can diminish the reduction of translation responses and increase the rotational responses in the high frequency range. These phenomena are more conspicuous as the embedment ratio is larger and the value of the wave velocity ratio of the soil and the foundation approaches to unity. When the high frequency components of the input ground motion are important and the basement has higher flexibility (for example ₂v_s/₁v_s >0.), the analysis method which considers the basement as a rigid foundation may lead to unsafety estimations and the estimation of the flexibility of the foundation is necessary as analysing the effective input motion with consideration of the incident waves.

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(³H) Tobramycin was used as a probe to determine the relationship between the structure of aminoglycoside antibiotics and their ability to remove this drug from its higher affinity binding site on the ribosome. The dissacharide moieties (neamine, tobramine, gentamine) appeared to have a common binding site, whereas the kanosamine, garosamine and ribose moieties determined the specificity of this binding. Amikacin and butikacin behaved in an anomalous manner in spite of their close structural relationship to tobramycin.

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The activities of tobramycin derivatives acetylated and ethylated on the '-N, 2'-N and 3-N positions were examined. The MICs of these derivatives against tobramycin sensitive strains indicated that 2'-N-ethylated and '-N-ethylated derivatives have a fairly good activity, and confirmed that the 3-N position is the most important one for antibiotic activity since 3-N derivatives were less active. The MICs of these derivatives against tobramycin resistant strains, and their inactivation by tobramycin modifying enzymes were examined. These results showed that 2'-N or '-N ethylation protects the drug against inactivation by AAC(2') or AAC('), respectively, and 2'-N-ethyltobramycin and '-N-ethyltobramycin were active against strains containing these modifying enzymes. On the other hand, 3-N ethylation protects the drug against inactivation by AAC(3) but 3-N-ethyl tobramycin does not inhibit strains containing this enzyme.

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The results of an investigation of soil liquefaction caused by the 1995 Hyogoken-Nambu earthquake are described. Massive and extensive soil liquefaction occurred in the coastal areas of reclaimed land, in old river beds, in Holocene deposits and in areas reclaimed from old ponds. A man-made island of weathered granite, or “Masado, ” was also seriously damaged by soil liquefaction. The maximum distance from the epicenter to the liquefied sites was approximately 90 km. Several characteristics of liquefaction formation, strong earthquake motions recorded on Port Island, and damage to structures from this earthquake are discussed.

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Elastic wave propagation in saturated soil is investigated in order to grasp the frequency dependent wave propagation property of actual soil. First, a closed form solution of Biot's equation is derived under a one-directional wave propagation condition. Then, the frequency dependent properties of waves in various soils such as clay, silt, sand, gravel and soft rock are computed and discussed. The behavior is shown to be classified into three states : low frequency, high frequency and transient. Properties hardly change in the low and high frequency states. The degree of saturation is shown to hardly affect the shear wave property, but it greatly affects the dilatational wave property, especially in a highly saturated condition. Permeability hardly affects the properties at low and high frequency states, but it does change the frequency range of the transient state. Next, the applicability of Biot's formulation is examined and the high frequency state derived from Biot's equation is shown to be valid when permeability is larger than that of silt. Finally, it is shown that various mechanical properties can be evaluated using the frequency dependent characteristics of the wave, some of which are difficult to measure in situ with conventional tools.

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A series of shaking table tests are made to investigate the uplift behavior of sewer pipes caused by liquefaction of surrounding soil. It is shown that uplift displacement of pipes buried in unliquefiable original soil, which does not allow a dissipation of excess pore water pressure from liquefied backfill soil, increases drastically when they are subjected to extensive shaking. Uplift displacement of pipes buried in liquefiable original soil, on the other hand, accumulates rather gradually even at moderate shaking. A different behavior on residual deformation of the backfill and the original soils is also observed. In relation to the effects of soil condition, damage to sewer pipes in Towada City caused by the December 28, 1994 Sanriku-Haruka-Oki earthquake is reported and discussed. It is estimated that upper backfill soil consisting of sandy gravel may have liquefied because it was under loose and saturated condition and was subjected to earthquake motion under nearly undrained condition due partly to its own low permeability and also to the existence of surrounding original soil with low permeability.

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During past earthquakes, several types of underground structure were damaged by uplift movement, because they were relatively light compared with the buoyancy force resulting from liquefaction of the adjacent subsoil by earthquake. To investigate this uplift behavior, a variety of model tests were conducted. In these tests, the uplift of underground structures was caused by both nearly instantaneous deformation of a surrounding subsoil layer and gradual movement of a pore fluid, while reconsolidation of liquefied soil resulted in settlement of the structure. Several different effects of structure type on uplift behavior were observed, including reduction of excess pore water pressure in a soil layer overlying completely-buried box structures and three dimensional deformation of the backfill soil surrounding a manhole together with deformation of original soils thus "squeezing" the backfill soil into the space occupied by the manhole. Analysis of the test results suggests that a safety factor against uplift, which was defined based on the equilibrium of vertical force acting on the structure, can be used to evaluate the triggering of uplift.

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During the 1993 Kushiro-Oki Earthquake, several sewer manholes in Kushiro Town were ejected up to 1.5m. In order to evaluate their failure mechanism, level and boring surveys, cut-off investigation and laboratory tests were carried out. It was estimated that the backfill soil which liquefied extensively moved laterally toward the bottom of the ejected manholes. Possible influences of the original subsoil on the uplift displacement are discussed together with the applicability of safety factor against uplift.

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In the seismic analysis of pile foundations the soil is often assumed to be an elastic material and the pressure at the soil pile interface is not limited during the analysis. This may result in a considerable error, as the computed pressure from an elastic analysis may go well beyond the ultimate lateral pressure of real soil. In fact, significant yielding at the soil-pile interface has been observed during real earthquakes, and also in laboratory tests. The yield zone is usually near the ground surface where the effect of inertial force due to the superstructure is higher. This yielding redefines the pile response, and in general cannot be ignored. In order to examine the effects of soil yielding on the internal pile response during earthquakes an approximate analysis is described in this paper which is an extension of a static method developed by the second author (1982) for the analysis of piles subjected to lateral soil movement. This method is then used to investigate the effects of soil yielding on the internal response of piles through a comparative study in which real earthquakes are used. It is shown that for strong earthquakes and heavily loaded piles the soil yielding may considerably increase the amount of maximum pile moment developed in the pile. A marked difference in the effects of yielding on the pile moment and shear is observed and discussed.

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The interaction between a penetrating shaft and the surrounding soil media under impact loading is a frequently encountered phenomenon in geotechnical engineering. Examples of such dynamic soil/shaft interaction would include dynamic pile driving, standard penetration testing (SPT), and dynamic driven rod test. Presented in this paper is a novel approach, based on the principle of dynamic system identification, which enables identification of dynamic soil-pile interaction model parameters. The analytical transfer function, relating the output stress wave forms to the input stress wave forms in the soil/shaft system, is derived using the Laplace and Fourier Transform techniques and the one-dimensional wave propagation theories. A numerical solution algorithm based on a variation of gradient method is coded into a micro-computer based program to solve the frequency-dependent soil-pile interaction parameters (Smith model) : soil damping and soil spring stiffness. To further reduce the amount of computational effort required in the solution of the frequency-dependent dynamic soil properties, it is suggested that the solution be obtained for the first-mode natural frequency of the measured stress waves. The results obtained from this simplified solution algorithm, when compared with both numerical simulations and controlled laboratory tests, are reasonably acceptable. The proposed parameter identification technique offers a viable alternative data interpretation procedure for deducing pertinent Smith model parameters used frequently in pile driving analysis.

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　Conçue comme une négativité infinie et absolue, l’ironie déclenche une déstructuration sémantique et diégétique. Dans En attendant Godot de Beckett， la fonction de chaque discours et de chaque action est systématiquement réduite à une méta-action négative, par quoi on peut définir la notion d’attente. Cette perturbation qui détraque les discours et les actions opère à tous les niveaux de la pièce．

’est la méthode de（dé）construction fondamentale chez Beckett，qui consiste à injecter en permanence de l’ironie pour subvertir l’ordre des choses． La même démarche ironique avait été adoptée par les préromantiques pour surmonter une difficulté soulevée par la philosophie idéaliste，à savoir la division entre les phénomènes et les choses en soi．Marqué par l’influence profonde de la pensée de Schopenhauer，Beckett se place dans le sillage idéaliste des préromantiques，et leur emprunte leur méthode d’évocation de l’inexprimable par le recours à l’ironie．

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This study was performed to clarify which factors affected damage to tame-ike (small embankment dams for irrigation) in Hokudan Town as a result of the January 17, 1995 Hyogoken-Nambu earthquake. Factors were assumed to be : Location (.g., Distance to Epicenter, etc.), Structure (.g., Angle to Nearest Fault, Embankment Volume, etc.), Soil Properties of Embankment, Geology of Dam Site and History (Era of Construction, Repaired, etc.). Multivariate statistical analyses were performed for documentary data (damaged : 181, undamaged : 328). Ordinary statistical analyses were conducted for the data investigated in situ for soil properties of the embankment. The results show that the factors causing damage to dam are : (1) Nearest Fault (Nojima, Mizukoshi and D2), (2) Distance to Nearest Fault (less than 500 m), (3) Distance to Epicenter (approximately to 14 km, which almost agrees with the location of seismic intensity 7 JMA), () Elevation of Dam Site (higher than 100 m), (5) Embankment Volume (the greater the volume the more damage was caused), () Direction of Dam Axis (normal or diagonal to the epicenter or to nearest the fault), (7) Plan View of Dam Axis (3 or axes), () Surface Geology of Dam Site (non-cohesive soil type ground), () Era of Construction (prior to 1891) and (10) Soil Properties of Embankment (sand, not silty sand or gravel, penetration resistance that is 10% smaller than the undamaged dams).

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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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