A sample of [³H] tobrarnycin (, 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 Beckmann rearrangement of aliphatic ketone oximes, R(CHs)=NOH (R=Et (1); n-Pr (2); iso-Pr (3); iso-Bu ()), with polyphosphoric acid (PPA), polyphosphate ester (PPE), and ester of phosphoric acid (2 P- R) was carried out and migratory ratios ((a)/() in eq. (1)) were determined, The results are shown in Fig.1, 2, and 3, respectively.
In Fig.1 and 2, the migratory ratios decrease with reaction time and nearly approach to the ratios of anti-alkyl form/syn-alkylform in benzene(A1) or DMSO(A2)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 A2. 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 2 P- 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 2 P- R.

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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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Two new partially saturated tricyclic ring systems, , a, 7, , , 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- (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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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), () 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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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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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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11-Amino-, a, 7, , , 10, 10a, 11-octahydrodibebenzo[, ]thiepines (a-d) and -oxepines (7a-d) were synthesized by the Leuckart reaction of , a, 7, , , 10, 10a, 11-octahydro-11-oxodibenzo[, ]thiepines (1a, )and -oxepines (2a, ) followed by hydrolysis of the reaction products a-d and a-d, respectively. The four diastereomers, cis(a-H, 10a-H)-cis(10a-H, 11-H) a and 7a, cis(a-H, 10a-H)-trans(10a-H, 11-H) and 7, trans(a-H, 10a-H)-trans(10a-H, 11a-H) and 7, and trans(a-H, 10a-H)-cis(10a-H, 11-H) d and 7d, 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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Two new polyacetylene compounds (, , 12)-1-acetoxy-3-isovaleryloxytetradeca-, , 12-trien-, 10-diyn-14-ol (), and (, , 12)-1-acetoxy-3-(2-methylbutyryloxy)tetradeca-, , 12-trien-, 10-diyn-14-ol () have been isolated along with (, , 12)-1-acetoxy-3-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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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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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 compared three groups of pregnant women: placebo with normotensive women, group A which included preeclamptics, and group which comprised preeclamptics who were supplemented their diets with vitamins and . MDA increased from . ± 2. (placebo) to .48 ± 1.2 (A) and .02 ± 1. nmol/gHb (). NO concentrations were enhanced from 19.3 ± .2 (P) to 23. ± . (A) and 24.1 ± . μmol/L (). GSH contents were decreased from 10.42 ± 2.81 (P) to .02 ± 2. (A) and .39 ± 1.02 μmol/g Hb (), whereas GSSG concentrations increased from 0.98 ± 0.28 (P) to 1.24 ± 0.29 (A) and 1.08 ± 0.12 μmol/g Hb (). SOD activity decreased 23% in A and 14% in ; GRx decreased 27% in A and .% in ; GPx decreased 12% in A and .% in . Catalase activity, however, increased 27% in A and 29% in as compared to control. Thus, we conclude that the use of vitamins and should be considered for the control of certain important biochemical indices during the development of preeclampsia; however, further studies are needed to develop methods for the prevention of preeclampsia in women at high risk.

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Nine isoquinoline alkaloids belonging to the protoberberine, proaporphine and bisbenzyl-isoquinoline series were isolated from Caryomene olivascens (Menispermaceae). Four compounds are new : (-)-2-norlimacine (), (-)-caryolivine (), (+)-1, 2-dehydro-2-norlimacusine () and N-formylstepharine (3). The last one is the first N-formyl derivative to be reported in the proaporphine group. Its biogenetic origin is discussed. Structures were established on the basis of 360 MHz (FT) nuclear magnetic resonance measurements and also by chemical correlation in the case of 3.

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