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 activities of tobramycin derivatives acetylated and ethylated on the '-N, 2'-N and -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 -N position is the most important one for antibiotic activity since -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, -N ethylation protects the drug against inactivation by AAC() but -N-ethyl tobramycin does not inhibit strains containing this enzyme.

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Two new polyacetylene compounds (, , 12)--acetoxy--isovaleryloxytetradeca-, , 12-trien-, 10-diyn-14-ol (), and (, , 12)--acetoxy--(2-methylbutyryloxy)tetradeca-, , 12-trien-, 10-diyn-14-ol () have been isolated along with (, , 12)--acetoxy--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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Two new partially saturated tricyclic ring systems, , a, , , , 10, 10a, 11-octahydro-11-oxodibenz [, ] oxepins (a and ), 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 a (trans), (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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The modulns of longitudinal elasticity and their temperature dependence in commercial aluminum cast alloys were measured in the temperature range from room temperature (20°) to 250° by the resonant frequency method. The results obtained are as follows:
The modulus of longitudinal elasticity tended to decrease weakly and linearly (the tangent of its decrease, m = (-2.--.) × 10²kg/cm²/°) with the rise of temperature. Within the range of the experiments, aluminum cast alloys were divided into groups, the lst group materials having large moduli of elasticity at room temperature (i. ., = (.15-.25) × 10⁵kg/cm²) were 2A-T, A-F, A-F, A-T, -F, -T, A-F, A-T, etc., the 2nd group materials having intermediate moduli (i. ., = (.85-.98) × 10⁵kg/cm²) were -F, -T, -T, -F, -T, A-F, etc. and the rd group materials showing considerably smaller moduli (i. ., = (.58-.65) × 10⁵kg/cm²) were A-F, A-T, 2A-F, etc. However, there were some differences between the moduli in this experiments and the moduli in the other data books, and these were considered due to the difference of the measurement principles and of hypotheses or assumptions involved in these principles, so it is suggested that the moduli of elasticity should be reported with indication of the measuring method.

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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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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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The ability of Climacodon septentrionalis to immobilize and kill a mycophagous nematode (Aphelenchoides sp.) in vitro is described for the first time. Two isolates produced droplets (20–45 μm in diameter) that formed at the apices of tall, stalked, and branching secretory cells (700–

,500 μm tall). On 2% modified malt extract agar, nematodes became enveloped in the droplets, which restricted their ability to move and resulted in complete immobilization and death within several hours of contact. The rate of decomposition of the nematodes varied considerably, with most individuals persisting for weeks whereas others were degraded within several days and appeared to be colonized by dense hyphal growth. This study provides the first documentation of a non-agaricoid fungus producing secretory cells that are able to immobilize nematodes.

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At present, analytical or empirical formula for seismic bearing capacity of footings adjacent to slopes is not available. This study uses a pseudo-static-based approach in conjunction with rigorous Janbu's slice method to derive analytical values of seismic bearing capacity factors (N_γ) and correction factors for the effects of inertia of soil mass and load inclinations for a rigid footing adjacent to cohesionless slopes. It is shown that both the bearing capacity factors (N_γ) and the correction factors for the seismic bearing capacity of footings placed on level ground derived herein are comparable with those reported in the literature. Empirical equations regarding the effects of slope angles and load inclinations, expressed using generalized forms of those proposed in the literature, are also derived. It is also found that the empirical equations derived in the present study provide values of correction factors in good agreements with the analytical ones, indicating the validity of using these empirical equations for assessing the bearing capacity of rigid footings situated on the slope subjected to pseudo-static seismic loading.

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The correction factor (η_ie) for the ultimate bearing capacity of a footing placed adjacent to a slope, taking into account the combined effect of horizontal and vertical seismic loads, represented by horizontal and vertical seismic coefficients, k_h and k_v, respectively, was derived using a modified Janbu's slice method. The influence of slope angles ‘α’ on the values of ‘η_ie’ are studied here. It was found that the values of η_ie can be expressed as an exponential function of ‘k_h/(-k_v)’ and ‘α’, with a measurable interdependency between ‘α’ and ‘η_ie’. The influence of ‘α’ on the value of ‘η_ie’ increases as the input value of ‘k_h/(-k_v)’ increases. Equations derived based on the analytical results are proposed to account for this effect. Based on the analyses of 11 near-fault seismographers obtained in the 1999 Chi-Chi earthquake in Taiwan, a ratio between the vertical and the horizontal seismic coefficients, λ, of between ±0.25 is suggested for including the combined effect of vertical and horizontal seismic forces in evaluating the seismic bearing capacity of footings located in near-fault areas.

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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.

4

), 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 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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カンキツ主要12種を用いて染色体のクロモマイシン (CMA) 染色を行った．染色体は CMA(+) バンドの有無および位置から 種類に区分できた．すなわち，CMA(+) を A: 両端および動原体近傍に有する，: 一方の端部と動原体近傍に有する，: 両端に有する，: 一方の端部に有する，: CMA(+) がない，F: 動原体近傍に有する，Dst: 付随染色体を有する 型，である．各種はこれらのうち 2～ 種類の染色体を有し，独自の CMA バンドパターンを示した．

C

. medica では 2 + + ，

C

. limon では + + + ，

C

. aurantifolia では 2 + + ，

C

. aurantium では A + + + + ，

C

. sinensis では 2+ 2 + + ，

C

. maxima では A + + + ，

C

. paradisi では 2A + + + ，

C

. ichangensis では 2 + 2 + 12 + 2，

C

. latipes では 2A + + + ，

C

. micrantha では + 11 + + 2Dst，

C

. macroptera では 2 + + 11 + + F，

C

. hystrix では + + + + 2F + Dst であった．

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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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わが国における主要中晩生および香酸カンキツ染色体のクロモマイシン (CMA) 染色を行った. 染色体はCMA(+) バンドの有無および位置から種類に区分できた. すなわち, CMA(+) をA: 両端および動原体近傍に有する, : 一方の端部と動原体近傍に有する, : 両端に有する, : 一方の端部に有する, : CMA(+) がない, である. 各種はこれらのうち, 種類の染色体を有し, 独自のCMAバンドパターンを示した. ハッサクではA+++, ヒュウガナツでは2A+2++, ‘川野なつだいだい’ではA+2++, ‘宮内伊予柑’ではA++++, タンカン‘垂水号’ではA++++, カボスでは+2++, スダチでは+2++およびユズ‘山根’では2++11+であった. 以上の結果, 本研究においても近縁の種間では似通ったCMAバンドパターンが観察された.

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