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 -dB frequency bandwidth, group delay ripple, rd-order distortion, and rd-order input intercept point (IIP) were 200MHz, .%, ≤ -55dB with a 100MHz input, and +10.dBm, respectively, all with a ±0.1Vp-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.V supply. Wide spurious-free dynamic range (SFDR) characteristics were confirmed up to high frequencies.

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The activities of tobramycin derivatives acetylated and ethylated on the '-N, '-N and -N positions were examined. The MICs of these derivatives against tobramycin sensitive strains indicated that '-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 '-N or '-N ethylation protects the drug against inactivation by AAC(') or AAC('), respectively, and '-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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(

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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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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Two new polyacetylene compounds (, , 12)-1-acetoxy--isovaleryloxytetradeca-, , 12-trien-, 10-diyn-14-ol (), and (, , 12)-1-acetoxy--(-methylbutyryloxy)tetradeca-, , 12-trien-, 10-diyn-14-ol () have been isolated along with (, , 12)-1-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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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/(1-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/(1-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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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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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 DESRA 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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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 -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 syntheses of (S)-13-hydroxy-(, , )-tetradecatrienoic acid (1) and (, , Z-tetradecatrienoic acid () 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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The Yura River in northern Kyoto Prefecture has long caused flood problems in its drainage basin. Specifically, areas downstream from Ayabe, where the river comes down from mountainous regions to a basin, frequently suffered from inundations,

.g., the Disaster Relief Law was applied eight times in the 60 years from 1953 to 2013. Against those background, river development projects, including levee construction and channel dredging, have been well underway since the late 1950s. The Ohno dam upstream on the main river was completed in 1961. However, the degree of flood safety remained low at that time. In 2004, the heaviest flood in the 50 years since 1953 occurred, followed in 2013 by a massive flood recording the highest water level since observations began at Fukuchiyama. The 2013 flood occurred in the midst of urgent levee construction and land raising based on a river infrastructure development project begun in response to a 2004 flood. This paper outlines damage from floods in 2004 and 2013 and shows the effects of these floods on the inundation depth of levees under development and the effects of the difference in rainfall characteristics in 2004 and 2013 on flood and fine sediment runoff. The effectiveness of the Ohno dam and misunderstandings by residents of the dam are also described. Important points in promoting river development from hard and soft measure are presented for making use of experiences the two disaster in the future.

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