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 ability of Climacodon septentrionalis to immobilize and kill a mycophagous nematode (Aphelenchoides sp.) in vitro is described for the first time. Two isolates produced droplets (20–45 μm in diameter) that formed at the apices of tall, stalked, and branching secretory cells (700–1,500 μm tall). On 2% modified malt extract agar, nematodes became enveloped in the droplets, which restricted their ability to move and resulted in complete immobilization and death within several hours of contact. The rate of decomposition of the nematodes varied considerably, with most individuals persisting for weeks whereas others were degraded within several days and appeared to be colonized by dense hyphal growth. This study provides the first documentation of a non-agaricoid fungus producing secretory cells that are able to immobilize nematodes.

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The design implication of stress-confinement effect of nonwoven geotextile is addressed. The unconfined and confined strengths of a selected needle-punched nonwoven geotextile are used to conduct a comparative design of a granular soil retaining wall based on a limit equilibrium approach. A higher wall may be allowed when considering the confined strength as compared to the unconfined strength. For a selected wall height, confined strength allows for fewer geotextile layers when compared to that designed using unconfined strength. It is recommended that stress-confinement test procedure should be standardized so that confinement effect of some nonwoven geotextiles may be incorporated into an individual wall design procedure.

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The gamma-ray spectrum and the conversion-electron spectrum are measured in the decay of the Tb¹⁵² activity. The L-subshell electron lines of the 586. keV +→2₁⁺ transition are separated by the ion-free beta-ray spectrometer. The M1-2 mixing ratio, δ², and the dimensionless ratio X of -2 mixing of the 586. keV transition are obtained to be δ²≤.16 and .034≤X≤.038, respectively. The 2 branching ratio (2; +→+): (2; +→2₁⁺): (2; +→0₁⁺) is determined to be .023 : 1. : ..

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It has been shown after mathematical and mechanical investigation that Limit Equilibrium Method (LEM) can be considered as a method to obtain the necessary condition of Slip Line Method (SLM), and that the solution can be obtained under the condition that F_s=1 and ∂F_s/∂θ=O, where F_s is the safety factor and θ is the inclination of the plane on which the safety factor is defined. Next, the generalized LEM (GLEM) is proposed, dealing with the following points : (1) Triangular or quadrangular blocks can be treated; (2) Safety factors are defined also on interblock planes; and (3) All types of plastic problems, slope stability, bearing capacity, and earth pressure are identically formulated. Two situations regarding treatment of the moment equilibrium condition are discussed. GLEM is applied to well-known problems. The results agree well with those obtained by theoretical methods. GLEM can be used to obtain the distribution of earth pressure or bearing capacity. GLEM, Iike ordinary LEM, is very effective for the practical problems, but GLEM is more theoretical and it can result in more accurate solutions.

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The gamma-ray spectrum and the conversion-electron spectrum are measured in the decay of the ^116mIn activity. Directional correlations are also measured for 818–1293 and 1097–1293 keV cascades. The M1-2 mixing ratio δ, and the -2 mixing ratio μ_k are obtained for 818. keV +→2₁⁺ transition to be δ=1.52−

0.22

+

0.26

, and μ_k≤

6

.1×10⁻⁴ respectively. The

E

2 branching ratio

B

(

E

2;

2₂

+→

0_g

+):

B

(

E

2;

2₂

+→2₁⁺):

B

(

E

2;

2₂

+→0₁⁺) is determined to be

0

.0158:1.

0

:

5

.86.

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The Nihonkai-chubu Earthquake, with a magnitude of ., occurred on May 26, 1983 in northwest Japan and produced liquefaction sites in the coastal plain of Akita and Aomori Prefectures. About one month later, the maximum aftershock, with a magnitude of .1, again induced liquefaction at several sites in Aomori Prefecture. The authors surveyed the affected area and discovered almost ten reliquefaction sites. Initial liquefaction at these sites had not occurred solely because of the main shock of the Nihonkai-chubu Earthquake. Initial liquefaction at some sites was attributable to the Niigata Earthquake in 1964, the Tokachi-oki Earthquake in 1968, and other earlier earthquakes. Although it had earlier been thought that the occurrence of reliquefaction would be improbable, the authors' investigation shows that reliquefaction occurs frequently, even when the acceleration caused by a later earthquake was less than that caused by a former earthquake. It can therefore be said that a site liquefied by an earthquake can be reliquefied by a subsequent earthquake.

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(, )

0.09O₃

thin films were formed on Pt(111)/Ti/SiO₂/Si(100) substrates by pulsed laser deposition using fourth-harmonic-generated light (λ=266nm) of a Nd³⁺: YAG laser beam. Crystallinity and stoichiometry of the thin films were determined by X-ray diffraction, X-ray fluorescence analysis and electron probe microanalysis. Their ferroelectric properties were investigated from electrical measurements. The leakage current density increased from 10^-11 to 10^-3 A·cm^-2 with increasing electric field up to 200kV·cm^-1. The dielectric constant, remanent polarization and coercive field of the

BaTi_0.91

(

Hf_0.5

,

Zr_0.5

)

0.09O₃

thin films were estimated to be 120 at 1kHz,

8.7μC·cm

-2 and 127kV·cm^-1, respectively.

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Engineering problems concerned either directly or indirectly with unsaturated soils are more and more common, ranging from aspects related to seepage to those related to shear strength and volume change. A few constitutive models have been conceived to describe and quantify these problems all of them with some advantages and drawbacks. Regarding mechanical behavior, the so-called Barcelona Basic Model (BBM) has achieved wide acceptance in geotechnical engineering, basically due to its simple mathematical formulation and good description of phenomena associated with unsaturated soils, especially collapse. Another concept that has emerged as a powerful framework to tackle three-dimensional states in granular materials is that of a modified stress tensor, such as t_ij. In this paper both BBM isotropic structure and t_ij concepts are combined to propose a new elastoplastic model for unsaturated soils, called t_ij-unsat. Modifications and generalizations for unsaturated states are introduced to accommodate those frameworks and overcome some inherited drawbacks. At the end of this work, experimental data gathered from specialized geotechnical literature is used to support the theoretical framework. The satisfactory agreement between simulations and tests results emphasizes the applicability of the proposed formulation to real boundary value geotechnical problems.

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We screened the differentiation-inducing activities of 39 mushroom extracts from Akita prefecture, Japan, on the mouse osteoblastic cell line, MC3T3-1. Sixteen phosphate buffered saline (PBS), 8 boiled PBS, 14 ethanol and 12 methanol extracts induced alkaline phosphatase (ALP) activities, an indicator of MC3T3-1 cell differentiation. The enzyme activities were markedly induced by extracts of Tricholoma auratum, and we isolated the active compound from methanol extracts of this mushroom. Physical data for the isolated active compound were identical to those for (,24R)-ergosta-,-diene-3β,,-triol (1). 1 induced ALP activities of MC3T3-1 cells and promoted cell proliferation. To investigate the relationships between the chemical structure and differentiation-inducing activity of the compound, ALP-inducing activities of MC3T3-1 cells by 1, ergosterol (2), ergocalciferol (3), cholesta-3β,,-triol (4), -dehydrocholesterol () and cholecalciferol () were tested. The enzyme activities of MC3T3-1 cells were increased 3.-fold by 10 μM 1 and 2.4-fold by 10 μM 4. However, 2, 3, and did not induce MC3T3-1 cell ALP activity at .1—10 μM. These results suggested that the OH groups at C- and/or C- of 1 and 4 played an important role in their differentiation-inducing activities on MC3T3-1 cells. Furthermore, 1 suppressed induction of MC3T3-1 cell apoptosis by serum starvation.

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One method currently being considered for the disposal of high level radio-active waste is burial in the seabed. When a hot object is buried in soil, the temperature of the soil adjacent to the object is raised and there is transient heat flow away from the object. The rise in the temperature of the soil causes excess pore pressures to be generated and transient pore water diffusion also takes place. A finite element formulation of the coupled heat flow and consolidation problem is presented. The computer implementation of this formulation is found to compare favourably with analytical solutions based on the same physical principles.

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Using the so-called pseudo-static method, a stability analysis was made for the mountain slide that took place at Mitake-iriya village at the time of the Izu-Ohshima-Kinkai earthquake of January 14, 1978. Undisturbed samples of volcanic clay were obtained in blocks from the exposed surface of the deposit identified to have been the sliding surface. The partially saturated clay samples were tested under consolidated undrained conditions using the triaxial test equipment. Dynamic axial stresses with irregular time histories were applied to the specimens in combination with statically sustained axial stresses to determine the soil strength under the conditions simulating in-situ states of stress during the earthquake. The results of the tests were expressed in terms of the Mohr-Coulomb type failure criterion which showed that, while the angle of internal friction remained almost unchanged, the cohesion component in irregular loading increased above values obtained in the static loading. Using the strength parameters thus determined, a pseudo-static analysis was made to check the stability of the soil masses that had actually slid during the 1978 earthquake. The maximum horizontal acceleration required to cause the slide was computed. The computed accelerations were shown to cover a range between 400 and 500 gals which is consistent with the range estimated by other investigators on the basis of overturning of tombstones in the vicinity of the slide area.

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A full account is given of the chemical behavior observed for , -dialkyladeninium salts (16). On treatment with boiling 1N aqueous NaOH for 60min, 16a, , , (X=I), 16c (X=Br), and 16f (X=ClO₄) rearranged to isomeric , -dialkyladenines (21a-f) in 50-% yields. Treatment of the salts with .N aqueous Na₂CO₃ at room temperature for 30-90min or with Amberlite CG-400 (OH^-) in H₂O at room temperature gave the ring-opened derivatives a-f (in the trans-formamide form) in 56-% yields, and rate constants for the ring-opening reactions of 16a, , -g (X=ClO₄) and 16c (X=Br) leading to a-g were determined in H₂O at pH .84 and ionic strength .50 at 25°C. Cyclization of a with NaH in AcNMe₂ at room temperature or with boiling 1N aqueous NaOH produced 21a in 84% or 72% yield, respectively.In solution, the trans-formamides seemed to transform slowly into the cis-formamides 23, attaining equilibria. The existence of such an equilibrium in or Me₂SO- at 25°C or in H₂O at pH .84 and ionic strength .50 at 25°C was kinetically confirmed in the case of a, and the mechanism of the rearrangement of 16 to 21 through is discussed on the basis of the above kinetic results and Deslongchamps' theory of stereoelectronic control. On treatment with NaBH₄ in MeOH at room temperature, 16a (X=I) furnished the , 8-dihydro derivative 28 (84% yield), which slowly decomposed in H₂O at 60°C to give a in 49% yield.The , -dialkyladeninium salts (16) were found to be obtainable from N'-alkoxy-1-alkyl--formamidoimidazole-4-carboxamidines () through an alternative synthetic route : Alkylations of with alkyl halides in HCONMe₂ in the absence of base, followed by hydrogenolysis of the N'-alkoxy group and cyclizatio (or vice versa) produced 16 in acceptable yields. In order to interpret the proton nuclear magnetic resonance spectrum of a, the 2-deuterated species 26 was also synthesized from 24 via 25 and 27.

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A new limit equilibrium analysis for assessing the stability of a reinforced embankment on soft clay against rotational undrained failure is presented. The analysis considers strain compatibility along the slip surface to deduce the tension mobilized in extensible reinforcement at collapse condition, and models strain softening of soils along the slip surface. The load extension responses of the reinforcement can be dependent on confinement by soils. Non-uniform increase in undrained cohesion during construction can be accounted for. The analysis yields a 'Safety Factor Curve' instead of a unique value for safety factor. A parametric study for illustrating the relevance of the proposed analysis is reported.

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A subloading surface constitutive model for clay is developed along a general theory proposed by Hashiguchi (1986). The novel part concerns introduction of a mixed (i.. composed of isotropic and deviatoric part) kinematic hardening parameter describing translation of the normalyield surface in the stress space to account for the induced anisotropy of clayey soils. The model is judged by comparisons with the element test data obtained for complex plane strain paths with up to two sharp bends.

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Using two direct introduction methods, DNA synthesis or cell proliferation activities of three purified proteins from . coli, namely, human papillomavirus (HPV) proteins of type 16, a mutant type 16 (24 C-G) (transformation defective) and type , were measured in mouse fibroblast, C127 cells. By a microinjection method, the order of the cell mitotic indexes for the three proteins as determined by -bromo-2'-deoxy-uridine (BrdU) staining was type 16, and 16 (24 C-G). By the osmotic shock method, the ³H-TdR incorporation and coloration by (3-carboxymethoxy phenyl)-2-(4-sulfophenyl)-2H-tetolazorium (MTS) for the three proteins correlated with the pRb binding and focus forming activities previously reported (hunger et al. 1991). These results indicate that the simple osmotic shock method for direct protein introduction may be generally useful for transformation assays of oncoproteins.

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