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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Stress wave theory is applied to open-ended pipe piles to clarify the effects of soil plug on the behaviour of piles during driving and static loading. Measured field data and various numerical models are reviewed ; methods are presented to calculate wave propagation in both the pile and the soil plug ; modelling is presented which takes into account the interaction between the soil plug and the pile ; also presented is simplified method to estimate the loadsettlement relation of the pipe pile in static loading. By correlating observed and calculated values in two analytical cases, the authors demonstrate that incorporation of the soil plug (modelled as a series of masses and springs) is required to correctly predict pile behaviour during driving and static loading.

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Six new cembranoids sarcophytol P (3), R (), S (), K (), (11), and T (13) were isolated from the soft coral Sarcophyton glaucum. Sarcophytol P (3) was shown to be the 20-hydroxy derivative of the major component sarcophytol A (), and afforded the cyclization product 6 in CHCl_3 at room temperature, in a same way as in . Sarcophytols R () and S () were correlated to , by conversion of its R,R and S,S epoxide derivatives. Sarcophytol K() was a 13, 14-dihydroxycembranoid having a ,3Z-diene moiety. The absolute configuration of and its Z,3- and Z,3Z-isomers sarcophytol B (2) and J (10) were determined by circular dichroism study of their bis-p-dimethylaminobenzoate derivatives. Sarcophytols (11) and T (13) were - and ,3Z-isomers of . Compound 11 showed characteristic broadening of the ^H-NMR chemical shifts, due to the restricted conformational interconversion. Using the three cembranoids sarcophytols (11, ,3), N (15, Z,3Z) and T (13,,3Z), spontaneous autoxidation-cyclization, in CHCl_3,was examined, in order to compare the stereochemical course of the reaction with that of (Z,3), which affords trans-fused bicyclo[.3.0]tetradecene systems. The ,3Z-isomer 13 gave the same cyclization product 18, as in the reaction of , even though it is isomeric at -,3. The Z,3Z isomer 15 gave 19, in consequence of the reversed geometry at -3 of 15. The ,3-isomer (11) gave the bicyclic product , having an antipodal fusion as compared with 19. This was confirmed by PCC oxidation of 19 and , giving enantiomeric ketones 23 and 24 respectively. The (14)-epoxide 26 was shown to be the immediate precursor of , and acounted for the inversion of the geometry at - of the cyclization product. Compound 26 is isomeric with the epoxide 17 derived from . The epoxide 17 is the postulated precursor in the conversion of 13 to 18. It is noteworthy that the mode of antipodal fusion of the cyclopentane rings, in 18 and , was controlled by the chirality of the epoxy rings. The -14 hydroxyl group participates in the transannular cyclization, but was found not to be the requisite functional group for the reaction. Similar treatment of cembrene (30), the parent hydrocarbon of , also reacted in CHCl_3 giving the bicyclic product 32.

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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 6'-N, 2'-N and 3-N positions were examined. The MICs of these derivatives against tobramycin sensitive strains indicated that 2'-N-ethylated and 6'-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 6'-N ethylation protects the drug against inactivation by AAC(2') or AAC(6'), respectively, and 2'-N-ethyltobramycin and 6'-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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This study aimed to determine the prevalence of fecal carriage of extended spectrum β-lactamase (ESBL) and/or plasmidic AmpC β-lactamase (pAmpC) producing Escherichia coli among dogs (n=428) in Turkey. Polymerase chain reaction (PCR) and sequencing were used to characterize genes encoding β-lactamase and plasmid mediated quinolone resistance (PMQR). Antimicrobial susceptibility testing and PCRs for virulence genes and phylogenetic groups were also performed. Cefotaxime resistant

. coli isolates were detected in (.2%) of the swab samples. Sequencing analysis results showed occurrence of various β-lactamase genes: bla_CTX-M-15 (62), blaTEM-

1b

(42), bla_CMY-2 (

22

), bla_CTX-M-3 (16), blaCTX-M-

1

(15), blaOXA-

1

(

9

) and bla_SHV-12 (3) alone or in combination. The most frequently encountered phylogenetic group was group

A₁

(35.

8

%), followed by group D₂ (

22

.

1

%), B

1

(15.

8

%),

D₁

(

9

.

5

%), A₀ (

7

.

4

%),

B2₂

(

5

.3%) and B2₃ (

4

.2%), respectively. PMQR genes, aac(6’)-Ib-cr,

qnrS1

and qnrB10 were detected in 25.3, 10.

5

and

1

.

1

% of the isolates, respectively. While all isolates were susceptible to imipenem and amikacin, resistance rates to non-β-lactam antibiotics ranged from 20.0% for tobramycin to 56.

8

% for tetracycline. The virulence genes were only detected in 34 (36.2%) of the isolates and this isolates carried single or various combination of virulence genes of iucD, papC, papE,

f17a

-A and eaeA. Four isolates were identified as human virulent pandemic CTX-M-15 producing

E

. coli clone O25b:ST131/B2. To the best of our knowledge, this is the first study to show fecal carriage of ESBL/pAmpC type β-lactamase producing

E

. coli isolates among dogs in Turkey.

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In view of the significant role of the water film effect in flow failure for a liquefied sandy deposit, the mechanism of water film generation is numerically studied based on a -dimensional model test. The process of water film growth and decay can be simulated to a certain extent by a simple consolidation analysis, which indicates that only a small difference in permeability in layered sand is enough for a water film to develop. A G shaking table test for a two-dimensional slope model with an arc of silt within a saturated sand is then addressed to discuss the dilatancy effect exerted in sheared sand during flow failure. It is possible that, once the water film is formed, the transmission of shear stress through it is interrupted, leaving the sand below free from the dilatancy ; this eventually allows the water film to stay without being absorbed during flow failure. The result of another shaking table test for a trapezoidal slope with horizontal silt seams indicate that water films beneath the seams enable the soil mass above them to laterally flow along water films very gently inclined even after shaking. If a silt seam breaks due to excessive pressure in the water film, it triggers re-liquefaction in the upper sand and leads to further instability.

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2-Benzyl--chloro--mercapto-3 (2H)-pyridazinone () was heated in ethanol under reflux for 10 hours to form concurrently 2, -dibenzyldipyridazo [, -b : ', '-]-, -dithiin-, 6 (2H, H)-dione (Ia) (57% in yield) and 2, -dibenzyldipyridazo [, -b : ', '-]-, -dithiin-, (2H, H)-dione (IIa) (14% in yield). Assignment of the two products to the corresponding structures is established by their physico-chemical constants and chemical behaviors. The concurrent formation of the dipyridazo [, -b : ', '-]-, -dithiin-, 6 (2H, H)-dione and the -, (2H, H)-dione were observed in, not only heating -chloro--mercapto-3 (2H)-pyridazinones (-3) in polar solvent, but warming -mercapto--chloro-3 (2H)-pyridazinones (-6) in the presence of potassium carbonate in DMF. For the interpretation of the reaction, keto-thioketo carbenes as active intermediate species and a reversible interconversion among them are suggested on the basis of the fact that there was nonexistence of an equilibrium between the two compounds, such as Ia and IIa, under the reaction condition and a trapping keto-thioketo carbene species as 2-phenylimino--benzylpyridazo [, -d]-, 3-dithiol- (H)-one (IVa) (14% in yield) along with the major products, (Ia) and (IIa), was furnished by warming with phenylisothiocyanate in the presence of triethylamine in dry benzene. On the contrary, participation of a reversible interconversion between Ia and IIa, to a considerable extent, with the concurrent formation of them in the case of benzylation of either Ib or IIb, by warming with benzylchloride in the presence of potassium carbonate in DMF at 80°, might not be neglected, because an attempted approach to an equilibrium between Ia and IIa in a similar reaction condition except the use of benzylchloride realized, whereas non-existence of an equilibrium between Ib and IIb in the similar reaction condition was observed.

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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 ±0.Vp-p input signal at each input terminal in the pseudodifferential configuration. The LPF including an output buffer dissipated 60mW in the case of a .2V supply. Wide spurious-free dynamic range (SFDR) characteristics were confirmed up to high frequencies.

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In the seismic analysis of pile foundations the soil is often assumed to be an elastic material and the pressure at the soil pile interface is not limited during the analysis. This may result in a considerable error, as the computed pressure from an elastic analysis may go well beyond the ultimate lateral pressure of real soil. In fact, significant yielding at the soil-pile interface has been observed during real earthquakes, and also in laboratory tests. The yield zone is usually near the ground surface where the effect of inertial force due to the superstructure is higher. This yielding redefines the pile response, and in general cannot be ignored. In order to examine the effects of soil yielding on the internal pile response during earthquakes an approximate analysis is described in this paper which is an extension of a static method developed by the second author (1982) for the analysis of piles subjected to lateral soil movement. This method is then used to investigate the effects of soil yielding on the internal response of piles through a comparative study in which real earthquakes are used. It is shown that for strong earthquakes and heavily loaded piles the soil yielding may considerably increase the amount of maximum pile moment developed in the pile. A marked difference in the effects of yielding on the pile moment and shear is observed and discussed.

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The interaction between a penetrating shaft and the surrounding soil media under impact loading is a frequently encountered phenomenon in geotechnical engineering. Examples of such dynamic soil/shaft interaction would include dynamic pile driving, standard penetration testing (SPT), and dynamic driven rod test. Presented in this paper is a novel approach, based on the principle of dynamic system identification, which enables identification of dynamic soil-pile interaction model parameters. The analytical transfer function, relating the output stress wave forms to the input stress wave forms in the soil/shaft system, is derived using the Laplace and Fourier Transform techniques and the one-dimensional wave propagation theories. A numerical solution algorithm based on a variation of gradient method is coded into a micro-computer based program to solve the frequency-dependent soil-pile interaction parameters (Smith model) : soil damping and soil spring stiffness. To further reduce the amount of computational effort required in the solution of the frequency-dependent dynamic soil properties, it is suggested that the solution be obtained for the first-mode natural frequency of the measured stress waves. The results obtained from this simplified solution algorithm, when compared with both numerical simulations and controlled laboratory tests, are reasonably acceptable. The proposed parameter identification technique offers a viable alternative data interpretation procedure for deducing pertinent Smith model parameters used frequently in pile driving analysis.

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 The stability of

‒tetrahydrocannabinol acetate (‒THC‒OAc) and ‒tetrahydrocannabinol acetate (‒THC‒OAc) in -liquid during storage was investigated. ‒THC‒OAc liquids in cartridges were stored at 80℃ or 30℃ for 28 days. The relative concentrations of cannabinoids in the liquids were measured by gas chromatography with flame ionization detection. ‒THC‒OAc decreased during storage at either temperature. ‒THC, a minor impurity, also decreased. ‒THC‒OAc liquid in a cartridge was stored at 80℃ for 57 days. The concentration of ‒THC‒OAc and ‒THC, a minor impurity, did not change during that time. Cannabinol acetate increased in all liquids, and unknown products were also detected by gas chromatography/mass spectrometry (GC/MS). The ‒THC‒OAc and ‒THC‒OAc liquids were subjected to GC/MS to detect representative diluents, glycerol, propylene glycol, and polyethylene glycol 400, but none of these were detected.

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The syntheses of (S)-13-hydroxy-(2, , )-tetradecatrienoic acid () and (2, , Z-tetradecatrienoic acid (2) 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 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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Four new sterols, , 6α-epoxy-(, 24R)-ergosta-(14), -diene-3β, -diol (), (, 24R)-ergosta-, -diene-3β, , 6β, -tetrol (2), (, 24R)-ergosta-, (11), -triene-3β, , 6β-triol (3) and 3β, , 6β-trihydroxy-(, 24R)-ergost--en--one (), have been isolated from the fruit bodies of Grifola frondosa (FR.) S. . GRAY (Polyporaceae)together with fourteen known ones (-18), of which two ( and 6) are reported for the first time from a natural source. The structures of these compounds were elucidated on the basis of spectral data.

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