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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This paper is concerned with dynamics of the standard penetration test (SPT). The usefulness of mounting strain gages at two different stations along a driven rod is described, together with a workable procedure of analysis. The analysis procedure makes use of the traveling time between the two gage points and enables one to identify the particle velocity, the displacement and the stress at any station of the rod, as well as the energy actually transmitted from a hammer to the rod. Particular attention is called for the consequence of inevitable, small errors in strain data upon such identifications. A pertinent procedure of error-correction is proposed and its validity is substantiated against the performance of well instrumented SPTs performed by the authors.

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The activities of tobramycin derivatives acetylated and ethylated on the 6'-N, '-N and -N positions were examined. The MICs of these derivatives against tobramycin sensitive strains indicated that '-N-ethylated and 6'-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 6'-N ethylation protects the drug against inactivation by AAC(') or AAC(6'), respectively, and '-N-ethyltobramycin and 6'-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 (4, 6, 12)-1-acetoxy--isovaleryloxytetradeca-4, 6, 12-trien-, 10-diyn-14-ol (), and (4, 6, 12)-1-acetoxy--(-methylbutyryloxy)tetradeca-4, 6, 12-trien-, 10-diyn-14-ol (C) have been isolated along with (4, 6, 12)-1-acetoxy--senecioyloxytetradeca-4, 6, 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 distribution of sarcophytol-A in the Sarcophyton genus was investigated in seven samples belonging to S. glaucum ( samples), S. infundibulifurme ( samples), S. crassocaule (1 sample) and S. trocheliophorum (1 sample) that were collected on Ishigaki Island in Okinawa Prefecture. Sarcophytol-A was present in one sample each of S. glaucum and S. infundibulifurme. This study indicates that the composition of cembranoids in the Sarcophyton genus is not related with the respective species, but with the individual samples collected.

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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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Autophagy is an intracellular degradation system regulating cellular homeostasis. The two ubiquitin-like modification systems named the Atg

system and the Atg12 system are essential for autophagy. Atg and Atg12 are ubiquitin-like proteins covalently conjugated with a phosphatidylethanolamine (PE) and Atg5, respectively, via enzymatic reactions. The Atg–PE conjugate binds to autophagic membranes and recruits various proteins through direct interaction, whereas the Atg12–Atg5 conjugate recognizes Atg, the enzyme for Atg, and facilitates Atg–PE conjugation by functioning as the enzyme. Although structural and biochemical analyses have well established the Atg-family interacting motif (AIM), studies on the interacting sequence for Atg12 are rare (only one example for human ATG12–ATG), thereby making it challenging to define a binding motif. Here we determined the crystal structure of the plant ATG12 as a complex with the ATG12-binding region of ATG and revealed that ATG12 recognizes the aspartic acid (Asp)–methionine (Met) motif in ATG via a hydrophobic pocket and a basic residue, which we confirmed critical for the complex formation by mutational analysis. This recognition mode is similar to that reported between human ATG12 and ATG, suggesting that the Asp–Met sequence is a conserved Atg12-interacting motif (AIM12). These data suggest that AIM12 mediates - interaction during Atg lipidation and provide structural basis for developing chemicals that regulate autophagy by targeting Atg12-family proteins.

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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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An analytical measure was developed so that the permanent displacement/deformation caused by seismic subsoil liquefaction can be predicted. Since the effects of topography on displacement is important, a three-dimensional analysis was developed which can fully consider the topography. Moreover, the loss of resistance in the surface unliquefied crust undergoing a tensile stress was taken into account. The empirical interpolation of the lateral displacement along the vertical axis helped reduce the amount of computation. Consequently, a finite-element two-dimensional analysis which is equivalent to a three-dimensional calculation was developed. The displacement obtained by the proposed method is the maximum possible to minimize the potential energy of the subsoil. By comparing the calculated displacement with the observation, the predicted displacement was to some extent greater than the observation. Hence, a dynamic analysis in the time domain, which was also developed by the authors, is necessary for a better matching between prediction and observation. In contrast, the direction of displacement was correctly predicted by the present analysis.

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We conducted a series of 1G large-scale shake table tests and cyclic eccentric loading tests of a shallow foundation model. The experimental parameters were the difference in loading methods (i.., dynamic and static), input seismic motions (i.., intensity and number of cycles), soil densities (i.., dense and medium dense), and the ratio of horizontal and overturning moment loads. The experimental data set contains the accelerations and displacements of the soil and foundation as well as the distributions of normal and shear reaction forces at the foundation base. The experimental results provide crucial data to model the coupling effect among vertical, horizontal, and overturning loads, the accumulation of irreversible displacement, and the foundation uplift, and so is one of the most complete benchmark data sets for the development and validation of numerical models for the nonlinear response of shallow foundations to strong earthquakes.

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The syntheses of (S)-13-hydroxy-(, 4, )-tetradecatrienoic acid (1) and (, 4, Z-tetradecatrienoic acid () were carried out by using the Wittig reaction as the key step. The asymmetric center at C-13 and the double bond between C- and C- 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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L'entree en Iran des armees britannique et sovietique s'est produite en aout 1941. Elle ebranla du coup le regime de la dynastie pahlavi qui etait au pouvoir depuis 16 ans, et mena le pays vers l'instabilite politique et le chaos social. La defaite de l'arme gouvernementale, qui etait le pivot du regime de Reza Shah, reduisit considerablement le controle du gouvernement central dans le pays. Cette situation politico-sociale confuse permit le developpement de differents mouvements politiques en Iran. C'est ainsi que le 16 aout 1942 le parti clandestin Komeley Jiyanewey Kurdistan (J-K) est ne a Mehabad, une ville au nord-ouest de l' Iran. Des sa formation, ce parti a su etendre sa sphere d'activite et, en une courte periode de temps, a fini par mettre sous son influence la ville et ses alentours. A la fin de la Seconde Guerre mondiale, en ete 1945, le J-K etait devenu une organisation representant le mouvement nationaliste kurde en Iran. C'est a ce moment-la qu'un autre parti politique, le Hizbi Dimokratiki Kurdistan (HDK), fonde par Qazi Mihemed a Mehabad aussi, devait remplacer le J-K. Des le janvier 1946, le HDK proclama l'instauration de la≪Republique de Kurdistan≫. Cependant, les troupes sovietiques qui avaient pris sous leur protection la Republique evacuerent les terres iraniennes, en mai 1946. Six mois plus tard, sous la pression militaire du gouvernement central iranien, la republique s'ecroula. Deux theories tentent d'expliquer le passage du J-K au HDK. William Eagleton Jr., par exemple, affirme dans The Kurdish Republic of 1946 que le HDK a ete cree sur le conseil des autorites sovietiques. L'ex-secretaire general du Parti Democratique du Kurdistan d'Iran, 'Ebd el-Rehman Qasimlu maintient par contre que Qazi Mihemed a etabli le nouveau parti de sa propre initiative, eu regard a la situation politique de cette epoque-la. Il considere que la passage du J-K au HDK comme etant l'evolution d'un parti nationaliste clandestin en un parti democratique. En analysant ces deux theories et en se basant sur les autobiographies des personages qui se sont engages dans cet evenement, cette etude tentera d'examiner le principe directeur et les activites du J-K et de mieux comprendre les raisons pour lesquelles le J-K devait etre remplace par le HDK. La conclusion generale portera sur les differents objectifs politiques du J-K et du HDK. Le J-K visait l'elevation du niveau culturel du peuple tout en luttant contre le tribalisme, qui etait, selon lui, le probleme majeur de≪la nation kurde≫, et cela en ecartant toute idee de revolte militaire. Le J-K a aussi exclu de son cadre les elites sociales telles que les leaders des tribus et dirigeants religieux de peur qu'ils n'excercent une influence sur les membres du parti. L'automne de 1944 fut le debut d'une nouvelle ere pour le mouvement kurde. Alors que l'espoir de l'autodetermination augmentait parmi le peuple a mesure que s'approchait la fin de la guerre, la necessite de la force militaire a commence a se faire sentir dans le J-K. C'est pour cela que s'est produite au sein du parti une tendance a compter sur l'aide militaire des sovietiques et a recourir au leadership de Qazi Mihemed, qui avait une certaine influence meme sur les leaders tribaux. Mais cette tendance etait essentiellement incompatible avec la ligne fondamentale du J-K et, graduellement, a prive ce parti de sa raison d'etre. Ainsi, le HDK se substitua au J-K en tant que≪parti democratique≫visant a rallier d'abord les elites sociales sous sa banniere, en s'appuyant sur l'autorite personnelle de Qazi Mihemed.

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This paper introduces a time-dependent radiation damping for the time-domain wave equation analyses of single piles. By deriving the radiation damping ratios of the linear viscoelastic soils along the pile from the dynamic impedance functions (Novak, 1974), time-dependent damping coefficients are obtained from the inverse Fourier Transform of these damping ratios and the static soil spring constants. Numerical examples are studied by solving the wave equations with the finite difference scheme. Applications of the modeling are presented and discussed with emphasis on identifying the primary factors that control the performance of piles. It is important to know that this solution, in contrast to the ordinary frequency-domain approach, can predict the softening load-displacement response of the piles under cyclic loads. The pile response under monotonic loads would be significantly influenced by the proposed damping parameters.

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The paper discusses the main aspects involved in numerical modeling of successive, large deformation, rigid body impacts in sand. The modeling was performed for the study of dynamic compaction of dry sand induced by repeated drops of a rigid tamper. Two dynamic finite element codes were used with a variety of soil models and computational algorithms. Large deformation effects and associated plastic behavior of the sand required special computational techniques of remeshing and reassignment of material properties. Consistency and stability of the formulations were evaluated based on their characteristics of convergency, accuracy, and computational efficiency. The adequacy of these models to represent actual soil behavior was evaluated by comparing computed results with available experimental data from an extensive laboratory investigation. The conclusions presented may serve as general guidelines relevant for this type of analysis.

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