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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(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 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 >.), 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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Stress wave theory is applied to open-ended pipe piles to clarify the effects of soil plug on the behaviour of piles during driving and static loading. Measured field data and various numerical models are reviewed ; methods are presented to calculate wave propagation in both the pile and the soil plug ; modelling is presented which takes into account the interaction between the soil plug and the pile ; also presented is simplified method to estimate the loadsettlement relation of the pipe pile in static loading. By correlating observed and calculated values in two analytical cases, the authors demonstrate that incorporation of the soil plug (modelled as a series of masses and springs) is required to correctly predict pile behaviour during driving and static loading.

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The activities of tobramycin derivatives acetylated and ethylated on the 6'-N, 2'-N and 3-N positions were examined. The MICs of these derivatives against tobramycin sensitive strains indicated that 2'-N-ethylated and 6'-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 6'-N ethylation protects the drug against inactivation by AAC(2') or AAC(6'), respectively, and 2'-N-ethyltobramycin and 6'-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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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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Field data indicate that the P-wave velocity in sand or gravel is sometimes much lower than that of water, even if the soil is below the water table. It is well understood that a slight decrease in saturation normally evaluated by the -value has a significant effect on undrained shear behavior like liquefaction of saturated soil. In the first part of this research, theoretical formulations of the -value, P-wave velocity and Poisson's ratio are made by taking into account the decrease in bulk modulus of water due to a mixture of air bubbles. Then, computations are carried out using formulas based on the soil properties of a typical sand or gravelly soils and Masa soil from the Kobe area to make charts correlating the variables. These charts indicate that a small decrement in the -value in the interval of =1. to . will considerably decrease the P-wave velocity. Thus, the P-wave velocity which is easily measured in the field can serve as a convenient index to quantitatively evaluate the insitu soil -value.

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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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The syntheses of (S)-13-hydroxy-(2, , )-tetradecatrienoic acid (1) and (2, , Z-tetradecatrienoic acid (2) were carried out by using the Wittig reaction as the key step. The asymmetric center at -13 and the double bond between - and - for natural compound 1 were reconfirmed as being of (S) configuration and , respectively. The relationship between the structure of the unsaturated hydroxy fatty acids and their inhibitory effect on the growth of lettuce was investigated.

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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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The mechanism of wave-induced instability in a permeable seabed have been studied for more than two decades. The distinction between shear failure and liquefaction, however, has not been clearly defined. This paper presents a fundamental study on the differences in two failure modes for a fully saturated seabed of both finite and infinite thickness. The wave-induced effective stresses and pore pressure, obtained from an analytical solution of Biot's pore-elastic consolidation theory, were employed to examine the failure modes under a two-dimensional plane strain condition. A case study is presented to examine the failure modes with respect to several parameters, such as excess pore pressure, seepage flow, seepage force, failure areas and stress path in the seabed. The conclusions obtained from this study were as follows ; (1) the thickness of a permeable seabed affects the pore pressure and effective stress response to ocean waves and the failure mode of the seabed, (2) either a liquefaction or shear failure, or both, occur in the seabed, even in the saturated seabed, (3) the Mohr-Coulomb's failure criterion, when combined with elastic stresses, can not be employed to estimate the liquefaction failure in the seabed, () the liquefaction can be evaluated by a criterion in terms of the excess pore pressure, (5) The liquefied zone in the seabed is significantly different from the shear failure zone. The shape beneath the seabed surface for the former is almost identical to the contour where the upward seepage flow is concentrated.

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The Nihonkai-chubu Earthquake, with a magnitude of ., occurred on May 26, 1983 in northwest Japan and produced liquefaction sites in the coastal plain of Akita and Aomori Prefectures. About one month later, the maximum aftershock, with a magnitude of .1, again induced liquefaction at several sites in Aomori Prefecture. The authors surveyed the affected area and discovered almost ten reliquefaction sites. Initial liquefaction at these sites had not occurred solely because of the main shock of the Nihonkai-chubu Earthquake. Initial liquefaction at some sites was attributable to the Niigata Earthquake in 1964, the Tokachi-oki Earthquake in 1968, and other earlier earthquakes. Although it had earlier been thought that the occurrence of reliquefaction would be improbable, the authors' investigation shows that reliquefaction occurs frequently, even when the acceleration caused by a later earthquake was less than that caused by a former earthquake. It can therefore be said that a site liquefied by an earthquake can be reliquefied by a subsequent earthquake.

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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 JMA), () Elevation of Dam Site (higher than 100 m), (5) Embankment Volume (the greater the volume the more damage was caused), (6) Direction of Dam Axis (normal or diagonal to the epicenter or to nearest the fault), () 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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In the 1993 Kushiro-oki Earthquake of Richter magnitude ., simultaneous recording of earthquake motions was successfully made at the ground surface and at a depth of 77 meters in a dense saturated sand deposit. The peak horizontal acceleration was .47 g on the ground surface and .21 g at a depth of 77 meters. The acceleration record at the ground surface showed a distinctive ground response, which consisted of a cyclic motion having a period of about 1.5 seconds overlain by a spike at each peak of the motion. In order to study the mechanism of this peculiar ground response, effective stress analysis was conducted on the dense saturated sand deposit. The model used for this study was a strain space multiple mechanism model, which takes into account the effect of principal stress axis rotation. The recorded earthquake motion at a depth of 77 meters was used as the input earthquake motion for the analysis. Sampling after in-situ freezing was done in order to evaluate the properties of the sand. The results of the analysis indicated that the observed ground response was due to the effect of dilatancy of sand, which plays a significant role in the response of the dense saturated sand deposits during strong earthquake motions.

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Two new partially saturated tricyclic ring systems, 6, 6a, , , , 10, 10a, 11-octahydro-11-oxodibenz [, ] oxepins (3a and 3), and -thiepins (a and ) were synthesized. Compounds a and were desulfurized to give a pair of isomeric 2-methylbenzoylcyclohexanes (10a and 10). Deuterated a and (11a and 11) were prepared starting from butadiene-d₆ (12). The stereochemical features of 3a (trans), 3 (cis), a (trans) and (cis) are compared with those of 10a, 10, 11a and 11 on the basis of proton nuclear magnetic resonance data.

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