Two new partially saturated tricyclic ring systems, , a, , , , 10, 10a, 11-octahydro-11-oxodibenz [, ] oxepins (a and ), 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 a (trans), (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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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)c and c, 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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A boron treated copper bearing HSLA steel containing austenite formers like manganese and nickel, somewhat lower in amount than that in HSLA 100 variety of steel is chosen for the study. The role of thermomechanical processing on the microstructure and mechanical properties of the above steel has been investigated. Differential scanning calorimetric study is carried out for understanding the precipitation behaviour of copper in HSLA steel under the influence of boron. The microstructure of the experimental steel is found to consist of laths of martensites and bainite. MA constituents of ribbon like morphology are observed at the lath boundaries. Higher strength properties of the steel are attributed to the presence of finely distributed precipitates of copper and microalloy carbides.

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A new analytical method is proposed for determining the inextensible grid reinforcement pullout resistance and pullout force/pullout displacement curve by using basic backfill soil and grid reinforcement properties. The pullout skin friction resistance/pullout displacement relationship is simulated by linear elastic-perfectly plastic model. A hyperbolic model has been proposed to represent the pullout bearing resistance/pullout displacement relationship in which the maximum bearing resistance of a single bearing member is determined using a new bearing capacity equation proposed in this paper. The influences of the grid bearing member spacing ratio, S/, the bearing member deflection rigidity, and the pullout softening behavior on the mobilization of pullout bearing resistance are explicitly included in the proposed model. Good agreement has been obtained between calculated values and laboratory test results.

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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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The advantages and disadvantages of using a back analysis of slope failures to evaluate soil shear strength are discussed. A methodology is presented herein that allows the implied level of reliability associated with soil shear strength parameters back calculated from slope failures to be estimated. A reliability approach is also used to estimate the probability of failure for a given limit equilibrium slope stability method, design factor of safety, and combination of back calculated Mohr-Coulomb shear strength parameters, c' and φ'. The methodology is illustrated using 39 landslides in the Orinda Formation in the San Francisco Bay area. The impact of additional case histories in the same geologic setting, i.., a larger data set, on the required design factor of safety for a given probability of failure is also investigated.

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From the fronds of Polystichum tripteron (KUNZE) P_R. a new norcarotenoid glycoside was isolated and shown to be (R, , R)--hydroxy-megastigma-4, -dien--one--O-β--glucoside. The fronds of Dennstaedtia wilfordii (MOORE) CHRIST. contain the same glucoside.

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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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-()-and-(Z)-Cyanomethylene-(a), (), p-nitrophenylmethylene (a), (), p-methoxyphenylmethylene (a), () and phenylmethylene (a), ()--deoxy-1, 2;, -di-O-isopropylidene-α--ribo-hexofuranose were prepared from 1, 2;, -di-O-isopropylidene-α--ribo-hexofuranos--ulose (4) and the corresponding Wittig reagents. In deacetonylations of these -methylene derivatives by ion exchange resin (IR-120), a, and a, gave rise to intramolecular cyclization products, , -anhydro--cyanomethyl-1, 2-O-isopropylidene-α--glucofuranose () and , -anhydro--p-nitrophenylmethyl-1, 2-O-isopropylidene-α--glucofuranose (11), respectively. While, a, and a, gave rise to the corresponding diol : -()-and-(Z)-p-methoxyphenylmethylene--deoxy-1, 2-O-isopropylidene-α--ribo-hexofuranose (12a), (12) and -()- and-(Z)-phenylmethylene--deoxy-1, 2-O-isopropylidene-α--ribo-hexofuranose (13a), (13).

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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 95 (.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

), blaCTX-M-

3

(16), bla_CTX-M-1 (15), bla_OXA-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 O25

b

:ST131/

B

2. 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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Melithasterols A- (1-4), isolated from a gorgoinan coral Melithaea ocracea of Okinawa, were shown to be cholestane-, 24-methyl--dehydrocholestane-, -dehydrocholestane-, and 24-methylenecholestane-derivatives. respectively, having a common β, α -dihydroxy-α, α-epoxy-Δ^ steroid nucleus. This was confirmed by direct comparison with the authentic sample prepared by lead tetra-acetate oxydation of cholest--ene- β, α, α-triol -monoacetate. Twelve new polyhydroxysterols were isolated from an Alcyonium sp. (,,), and Sclerophytum sp. (14,16,19,20,21,a,23,26,28) soft corals collected off the coasts of the Andaman and Nicobar Islands in the Indian Ocean. All the Sclerophytum sp. soft corals contained 17a or its 25-deacetyl derivative. Compounds to were identified as 24-methylenecholest--ene- β, 16β-diol--0-α-L fucoside () and its β-() and α-hydroxy () derivatives. Compound 14 was shown to be 24S-24-methylcholest--ene-β,25ξ,26-triol and was correlated to the known compound 15 by α, β-glycolation. Compound 16 was shown to be β, α-isomer of 17, correlating to 17 by PCC oxidation followed by dehydration. Compound 19 was identified with 25-deacetyl derivative of the known compound lobosterol (19a) by hydrolysis of authentic lobosterol. Compounds 20 and 21 were shown to be -dehydro-(20) and -dehydro-(21) derivative of 17a and 17, respectively, by comparisons of their spectral data with reference compounds. Compounds a and 23 were 24S-methylcholestane-β, α 25-triol--one 25-monoacetate (a) and its 25-deacetoxyl derivative (23). Partial PCC oxidation of 17a afforded a. Compounds 26 (andamansterol) and 28 (nicobarsterol) were shown to be gorgost--ene-β, α. 11α, 21-tetrol and novel secosteroid, 11,21-cyclo--homo-11-oxa-, 11-secoergostane-β, α, 12ξ-triol--one, respectively, by spectral analyses (H-HCOSY, HMQC, HMBC).

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The present paper aims at developing a simplified model for a stress-strain relationship at small strains up to an initial yielding of homogeneous saturated frozen sand. The modelling of elastic moduli for an ice-sand mixture as a composite geomaterial is first introduced based on previous studies, where a saturated frozen sand is treated as the icesand mixture. The applicability of modelling the elastic moduli under constant temperature is then discussed from the theoretical and experimental points of view. In addition, the hyperbolic stress-strain modelling of saturated frozen sand at small strain is presented. The effect of the volume fraction of sand, stiffness of sand inclusion and temperature changes on the elastic moduli and the stress-strain behaviour up to about 1-2% axial strain, which is defined as an upper yield stress, are investigated through the model, whose applicability is verified in comparison with the experimental data.

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The solubility and supersolubility of L-phenylalanine in aqueous solutions is firstly reported in this work. At temperatures from 273.15 to 343.15 K, both solubility and supersolubility in water generally increase with the temperature, and the average metastable zone width is about .°C. At the temperature of 298.15 K, the solubility remarkably decreases with an increase in the concentration of ethanol, which indicates that ethanol can be used as an antisolvent for the precipitation and crystallization of L-phenylalanine. When sodium chloride is added to the solution, the solubility of L-phenylalanine increases with the concentration of sodium chloride.

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Agaricus blazei is an important fungus for producing bioactive compounds. There are some reports of polysaccharides and steroid derivatives from the fruiting bodies of A. blazei. However, the chemical examination of the secondary metabolites of the cultured mycelia of this species has not been reported. Eight compounds, an unprecedented skeleton have been isolated from the cultured mycelia of A. blazei. The structures of the novel compounds each named blazeispirols A (1), (2), C (), (4), () X(), Y () and Z () were confirmed by extensive 1 and 2 NMR spectral data and X-ray analysis. Blazeispirols A (1), (2), C (), (4) and () were des-A-ergostane type compounds having spiroacetal structure as a side chain. Blazeispirols X () and Y () were determined to be (20S, S, 23R, 24S)-1 (10→) abeo-14β, :, 25-diepoxyergosta-,,,11-tetraene-α,23-diol and (20S, S, 23R, 24S)-14β,:,25-diepoxy-,23-dihydroxyergosta-4,,11-triene-,-dione by comparison of extensive 1 and 2 NMR spectral data with that of blazeispirol A. The biosynthesis of blazeispirol A was investigated by feeding ^<13>C-labeled acetates and methionine to the growing cultures of A. blazei. The labeling patterns of 1 derived from singly and doubly ^<13>C-labeled acetates were consistent with that of ergosterol reported previously except for the A-ring and then ^<14>C-labeled ergosterol was incorporated into blazeispirol A. Taking the structures of blazeispirols Z and into consideration, it can be assumed that blazeispirol A is biosynthesized from ergosterol by the cleavage of C-4, C- and C-1, C-10 bonds on retro aldol condensation and Michael reaction via such as intermediate A as shown in Fig. 4. A large number of ergostane-type steroids have been isolated from many fungi. However, blazeispirol A is the first example of a naturally occurring des-A-ergostane-type steroid including a spiroacetal structure moiety as a side chain.

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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, C: 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4, 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1A+1C++, ヒュウガナツでは2A+2C++, ‘川野なつだいだい’では1A+2C++, ‘宮内伊予柑’では1A+1+1C++, タンカン‘垂水1号’では1A+1+1C++, カボスでは+2C++, スダチでは1+2C++およびユズ‘山根’では2+1C+11+4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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