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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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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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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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 -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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Chemical synthesis of (, 24R)- and (, 24S)-, 24-dihydroxy--vitamin has been achieved starting with the commercially available dinorcholenic acid acetate. Synthesis involved introduction of the -hydroxy group by a reduction of the , 2-epoxide generated by epoxidation of the , 4, -trien-3-one. The side chain on the steroid was then constructed by means of a Wittig reaction followed by introduction of the Δ⁷ bond by standard methods and its protection with -phenyl-, 2, 4-triazoline-3, 5-dione. Subsequent reduction of the hydroxy groups in the steroid side chain followed by reduction of the Diels-Alder addition products yielded the both 24-isomers. The 5, 7-dienes were irradiated and the corresponding vitamin compounds isolated. Nuclear magnetic resonance was used to identify individual isomers. The (, 24S)-, 24-hydroxyvitamin compound bound equally well to the chick intestinal cytosol receptor as , 25-dihydroxyvitamin , while the 24R-isomer was approximately ten times less active. In vivo, both isomers were less active than , 25-dihydroxyvitamin ; however, the 24S-isomer was considerably more active than the 24R-isomer approaching the activity of , 25-dihydroxyvitamin .

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Glucosylceramide (-Cer) was isolated from the spermatozoa of the starfish, Asterias amurensis. The long-chain bases of the glycolipid consisted of dihydroxy (18:2, 18:3, 19:3, and :2), and trihydroxy (t:) types. Long-chain aldehydes derived from them were analyzed mainly by proton nuclear-magnetic resonance to determine the detailed structures. Two of the tri-unsaturated bases were identified as (, , )-2-amino-4, 8, 10-octadecatriene-, 3-diol (18:3) and (, , )-2-amino--methyl-4, 8, 10-octa-decatriene-, 3-diol (19:3), which is a novel base. Both :2 and t: had a cis double bond at the C or C13 position. All fatty acids were 2-hydroxylated (C₁₄-C₂₅):Most of themwere saturated and unbranched. About 10% was mono-unsaturated and unbranched (-C₂₅), while saturated but branched (iso- and anteiso-types) C₁₅-C₁₈ acids were found as mi-nor components. The main fatty acids, which summed up to more than 93% of the fatty acids in the glucosylceramide, were n-14h: , n-15h:, n-16h : , n-17h : , n-18h : , and n-24h:.

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The dual stage actuation (DSA) is one of the most attractive methods for increasing the track density of hard disk drives (HDDs). We have developed a φ-shaped actuated suspension as a fine actuator for a DSA system. The developed suspension's main resonance frequency was higher than kHz, its generated displacement was larger that - m at an applied voltage of 30 V and its shock resistance was greater than 3000 G. Flying-height variance caused by DSA driving (+/- V) was less than .3 % of nominal flying-height. The decrease of displacement was almost constant, less than 5 % after driving-cycles under heavy conditions (+/- 30V at 100℃, +/- 30V at ℃ and % humidity). Based on these data, we concluded that our actuated suspension can maintain a stable flying-height during its operation and its lifetime is as long as other actuators for HDDs.

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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

), 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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Calcium-silicate-hydrate/aminobenzoic acid (C-S-H/ABA) composite systems were synthetized and characterized for the first time. Each of 3- or 4-aminobenzoic acid with a concentration of .01 mol. per mol. of Ca was added to the C-S-H preparations during their hydration. The C-S-H/ABA systems were filtered and dried after three weeks. These were, then, characterized by X-ray diffraction, Fourier transform infrared spectroscopy and nitrogen adsorption analysis. Porous bodies were also prepared from C-S-H/ABA compacted powders and used for the length-change and mass-change measurements in different test solutions. In addition, the microindentation technique was used to determine the creep modulus and hardness of the compacted samples. It is suggested that the C-S-H/ABA systems had improved durability and enhanced mechanical properties compared to the phase pure C-S-H reference materials. The influence of the 3- and 4-aminobenzoic acid on durability factors was similar. The C-S-H/3-ABA, however, had superior mechanical performance.

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The main objective of this paper is to compare safety factors obtained from Morgenstern-Price, Janbu and Spencer methods with the factors calculated from the modified variational approach (Leshchinsky and Huang, 1992a). Such comparison is essential since there is no mathematical proof that the variational analysis indeed yields a minimum and thus, physically produce significant results. The safety factors compared well, indicating the variational analysis is on a par with acceptable existing rigorous methods. Availability of a user-friendly computer code may make the variational analysis useful to practicing engineers. However, its greatest potential at the moment is in 3- applications; i.., unlike other methods, its extension to 3- is straightforward.

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We reported a case of basal cell nevus syndrome (BCNS) . A 12-year old boy visited us for the examination of numerous skin pits on the palms. He showed hypertelorism, mandibular cyst, calcification of the falx, and mental retardation. Clinical diagnosis of BCNS was made by these findings. Examination of other family members did not reveal palmar pits or any other signs of BCNS. Skin biopsy from the palmar pits showed reduced thickness of the stratum corneum and the presence of basal cell carcinoma in the dermis.
Chromosome-analysis of peripheral leukocytes revealed the deletion of q21.3-.. His parents did not show any abnormalities in chromosome-analysis. Very few cases of BCNS have been reported that have basal cell carcinoma on the palms. [Skin Cancer (Japan) 2000; 15: 27-30]

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