Two new partially saturated tricyclic ring systems, , a, , , , 10, 10a, 11-octahydro-11-oxodibenz [, ] oxepins (3a and 3), and -thiepins (4a and 4) were synthesized. Compounds 4a and 4 were desulfurized to give a pair of isomeric 2-methylbenzoylcyclohexanes (10a and 10). Deuterated 4a and 4 (11a and 11) were prepared starting from butadiene- (12). The stereochemical features of 3a (trans), 3 (cis), 4a (trans) and 4 (cis) are compared with those of 10a, 10, 11a and 11 on the basis of proton nuclear magnetic resonance data.

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An empirical equation in use for estimating the pseudo-elastic shear modulus, G_f, of subsoil, associated with shear strains less than .001% is proposed in this paper. In a series of in-situ seismic cone tests performed nationwide, the profiles of both G_f and the in-situ void ratio, , with depth were successfully characterised at five sites, each comprising a soft clay layer deposited in the Holocene era. The database which comprised the original data from the field and laboratory tests, coupled with similar information on well-documented Holocene clay deposits in Europe, was statistically analyzed in attempts to determine a generalised relationship with which G_f of soft clay may be reasonably estimated only from routinely available borehole data; that is and the current geostatic effective overburden pressure, σ'_v. An empirical relationship, G_f=, 000 -√(σ'_v) (kPa), was derived from the statistical analysis applied to data from seven different clays worldwide, for which extended over a range between 1 and , and the overconsolidation ratio ranged roughly between 1 and 2. The applicability of the proposed relationship was evaluated for two case records, each in which the clay exhibited unusual behavior; i.., the undrained shear strength remained more or less constant with depth due to the existence of artesian pressure at one site, and, at the other, G_f decreased, whereas increased, with depth. It was demonstrated that even in these clay deposits exhibiting exceptional profiles, the proposed relationship was capable of predicting G_f with a reasonable accuracy by determining the profiles of and σ'_v with depth. In addition, the prediction when compared to G_max from carefully performed laboratory cyclic tests, yielded a better estimate of G_f from the in-situ seismic survey. Despite the fact that the empirical relationship was initially designated to estimate G_f of soft clays, it may be equally applicable to sandy deposits. This was verified by comparing it to similar, and well-established, relationships developed for sands. A case record as such is also described for a loose sand deposit at Higashi-Ohgishima in Tokyo Bay which was placed in 1960's by land reclamation.

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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 (4)), 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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11-Amino-, a, , , , 10, 10a, 11-octahydrodibebenzo[, ]thiepines (a-) and -oxepines (a-) were synthesized by the Leuckart reaction of , a, , , , 10, 10a, 11-octahydro-11-oxodibenzo[, ]thiepines (1a, )and -oxepines (2a, ) followed by hydrolysis of the reaction products 4a- and a-, respectively. The four diastereomers, cis(a-H, 10a-H)-cis(10a-H, 11-H) a and a, cis(a-H, 10a-H)-trans(10a-H, 11-H) and , trans(a-H, 10a-H)-trans(10a-H, 11a-H) and , and trans(a-H, 10a-H)-cis(10a-H, 11-H) and , 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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This paper outlines a mathematical description of the stress dilatancy behaviour of granular materials which accounts for stress level and void ratio dependencies. The consideration of these aspects has important implications in the modelling of granular material behaviour. In fact, granular material mechanical response is largely dominated by the evolution of dilatancy, fabric and void ratio histories. The starting point in this study is the well established Rowe's theory which is revisited and ultimately modified by introducing a factor linked to governing state parameters in order to describe the complete behaviour of granular materials during deformation. Numerical simulations of triaxial tests on granular materials at different void ratios and stress levels are herein presented to illustrate the model.

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In this paper, consideration is given as to how to characterize depth-variation for the small-strain shear modulus of natural clay sedimentation, in a state of normal consolidation. A case study was carried out for a relatively uniform clay layer deposited in the Holocene era. Initially, the effects of both strain and in-situ stress levels on secant shear modulus were carefully examined in cyclic torsion shear tests using undisturbed samples, which were recovered at different depths in a test borehole. The range of shear strain examined was between .001% and 1%. Similar examination was made for a silty clay using reconstituted samples that were isotropically consolidated at different stress levels. On the basis of the results of these laboratory tests, together with the shear modulus from an in-situ seismic survey, the small-strain shear modulus was formulated in terms of the stress and strain levels, and linked also to undrained shear strength. Interactions of the small strain stiffness between in-situ and laboratory are discussed in depth with an attention paid to the existing aging effect in the original subsurface condition.

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The design implication of stress-confinement effect of nonwoven geotextile is addressed. The unconfined and confined strengths of a selected needle-punched nonwoven geotextile are used to conduct a comparative design of a granular soil retaining wall based on a limit equilibrium approach. A higher wall may be allowed when considering the confined strength as compared to the unconfined strength. For a selected wall height, confined strength allows for fewer geotextile layers when compared to that designed using unconfined strength. It is recommended that stress-confinement test procedure should be standardized so that confinement effect of some nonwoven geotextiles may be incorporated into an individual wall design procedure.

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A full account is given of the chemical behavior observed for , -dialkyladeninium salts (16). On treatment with boiling 1N aqueous NaOH for 60min, 16a, , , (X=I), 16 (X=Br), and 16f (X=ClO₄) rearranged to isomeric , -dialkyladenines (21a-f) in 50-% yields. Treatment of the salts with .N aqueous Na₂CO₃ at room temperature for 30-min or with Amberlite CG-400 (OH^-) in H₂O at room temperature gave the ring-opened derivatives a-f (in the trans-formamide form) in 56-% yields, and rate constants for the ring-opening reactions of 16a, , -g (X=ClO₄) and 16 (X=Br) leading to a-g were determined in H₂O at pH .84 and ionic strength .50 at 25°. Cyclization of a with NaH in AcNMe₂ at room temperature or with boiling 1N aqueous NaOH produced 21a in 84% or 72% yield, respectively.In solution, the trans-formamides seemed to transform slowly into the cis-formamides 23, attaining equilibria. The existence of such an equilibrium in or Me₂SO- at 25° or in H₂O at pH .84 and ionic strength .50 at 25° was kinetically confirmed in the case of a, and the mechanism of the rearrangement of 16 to 21 through is discussed on the basis of the above kinetic results and Deslongchamps' theory of stereoelectronic control. On treatment with NaBH₄ in MeOH at room temperature, 16a (X=I) furnished the , -dihydro derivative 28 (84% yield), which slowly decomposed in H₂O at 60° to give a in 49% yield.The , -dialkyladeninium salts (16) were found to be obtainable from N'-alkoxy-1-alkyl--formamidoimidazole-4-carboxamidines () through an alternative synthetic route : Alkylations of with alkyl halides in HCONMe₂ in the absence of base, followed by hydrogenolysis of the N'-alkoxy group and cyclizatio (or vice versa) produced 16 in acceptable yields. In order to interpret the proton nuclear magnetic resonance spectrum of a, the 2-deuterated species 26 was also synthesized from 24 via 25 and 27.

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Mycobacteriocin produced by human type tubercle bacilli could be demonstrated easily on eggmedium containing .05% tween 80 by means of stab culture or streak plate methods, and elevenmycobacteriocin-types have been recognized on the basis of the inhibition pattern by using indicator strains of rapidly growing mycobacteria.
At present, types 1 (4.%), 2 (13%), 4 (38.%), (2%) and 11 (14.%) showed a stablemycobacteriocin pattern, but types 3 (.%) and (.%) were apt to show type replacement totypes 2 and 4, respectively, and strains belonging to types , and were few, less than 1.%to the total. In order to perform a reproducible mycobacteriocin typing, our previous typingscheme was revised to be consisted of five groups (A-). Among 438 strains, mycobacteriocingroup containing types 4 and was 46.1% of strains tested, group containing types 2, 3 and was .%, group containing type 11 was 15.1%, group A containing types 1 and was.%, group containing types and 10 was 4.1%, and untypable strains were no more than .% among all tested strains.
Human type tubercle bacilli classified as type 4, which consisted of more than 45% of strainstested, could be divided into three sub-types from sensitivity to M. gordonae 1324 and M. terrae 1450.
Mycobacteriocin producing strains belonging to type : showed an extremly wide antibacterialactivity to strains of more than % of rapidly growing mycobacteria (42 strains), to about 40% of slow growing mycobacteria (29 strains), and even to 10 strains of Staphylococcus aureus.

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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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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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It has been shown after mathematical and mechanical investigation that Limit Equilibrium Method (LEM) can be considered as a method to obtain the necessary condition of Slip Line Method (SLM), and that the solution can be obtained under the condition that F_s=1 and ∂F_s/∂θ=O, where F_s is the safety factor and θ is the inclination of the plane on which the safety factor is defined. Next, the generalized LEM (GLEM) is proposed, dealing with the following points : (1) Triangular or quadrangular blocks can be treated; (2) Safety factors are defined also on interblock planes; and (3) All types of plastic problems, slope stability, bearing capacity, and earth pressure are identically formulated. Two situations regarding treatment of the moment equilibrium condition are discussed. GLEM is applied to well-known problems. The results agree well with those obtained by theoretical methods. GLEM can be used to obtain the distribution of earth pressure or bearing capacity. GLEM, Iike ordinary LEM, is very effective for the practical problems, but GLEM is more theoretical and it can result in more accurate solutions.

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Circuit techniques to enhance the linearity of input-voltage-to-current (V/I) conversion and to increase the output impedance of a current source by compensating for the low intrinsic gain of a transistor were introduced to realize a high-frequency operational transconductance amplifier (OTA) for a low supply voltage using sub-100-nm CMOS processes. Applying these techniques, a MOS th-order Gm- linear-phase low-pass filter (LPF) was realized using a 65nm CMOS process. A simplified biquad LPF that can serve as a component of a th-order LPF was newly developed by replacing OTAs with resistors. As a result, the -3dB frequency bandwidth, group delay ripple, 3rd-order distortion, and 3rd-order input intercept point (IIP3) were 200MHz, 2.2%, ≤ -55dB with a 100MHz input, and +10.3dBm, respectively, all with a ±.1Vp-p input signal at each input terminal in the pseudodifferential configuration. The LPF including an output buffer dissipated 60mW in the case of a 1.2V supply. Wide spurious-free dynamic range (SFDR) characteristics were confirmed up to high frequencies.

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Among the rivers damaged by the earthquake, two most severely damaged along the Yodo-gawa River are described. In the left levee, the settlement exceeded 2 m for a length of 1.4 km, with a maximum settlement of 3 m. Sand boils were observed extensively on the ground surface near the damaged dikes. Holocene sandy soil with an SPT N-value of 10 or less existed in the upper part of the subsoil profile. These facts indicate that liquefaction of the soil was the major cause of the embankment damage. The cyclic stress ratio required to cause liquefaction was .30 as determined from cyclic triaxial tests on undisturbed samples.

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The behavior of the soft clay grounds subjected to repeated loading is different from that subjected to sustained loading. The difference in settlement between these two loading patterns should be due to secondary compression over a long period of time. Consequently, soft clay grounds subjected to repeated loading tend to be more compressible than those subjected to sustained loading. Therefore, it is necessary for engineers to predict post-construction settlements under repeated loading. In this respect, the preloading is considered to be promising as a countermeasure to reduce the settlement of clay under repeated loading as well as under sustained loading. The effect of preloading on post-construction consolidation settlement of soft clay subjected to repeated loading after removal of a part of preload is investigated in the present paper. It has become clear that the settlement of a clay sample after preconsolidation is mainly affected by the amount of preload, the degree of consolidation due to the preload, the amount of permanent load and the amount of repeated load after removal of preload. The calculated settlement versus time relations using a method to estimate the amount of consolidation settlement of soft clay grounds subjected to repeated loading after removal of preloading were compared with the observed degree of consolidation as parameters of the intensities of preload and repeated load.

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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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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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