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–

,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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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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We screened the differentiation-inducing activities of 39 mushroom extracts from Akita prefecture, Japan, on the mouse osteoblastic cell line, MC3T3-. Sixteen phosphate buffered saline (PBS), boiled PBS, 14 ethanol and 12 methanol extracts induced alkaline phosphatase (ALP) activities, an indicator of MC3T3- 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,5α,6β-triol (). induced ALP activities of MC3T3- 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- cells by , ergosterol (2), ergocalciferol (3), cholesta-3β,5α,6β-triol (), -dehydrocholesterol (5) and cholecalciferol (6) were tested. The enzyme activities of MC3T3- cells were increased 3.0-fold by 10 μM and 2.-fold by 10 μM . However, 2, 3, 5 and 6 did not induce MC3T3- cell ALP activity at 0.—10 μM. These results suggested that the OH groups at C-5 and/or C-6 of and played an important role in their differentiation-inducing activities on MC3T3- cells. Furthermore, suppressed induction of MC3T3- cell apoptosis by serum starvation.

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The mechanism of wave-induced instability in a permeable seabed have been studied for more than two decades. The distinction between shear failure and liquefaction, however, has not been clearly defined. This paper presents a fundamental study on the differences in two failure modes for a fully saturated seabed of both finite and infinite thickness. The wave-induced effective stresses and pore pressure, obtained from an analytical solution of Biot's pore-elastic consolidation theory, were employed to examine the failure modes under a two-dimensional plane strain condition. A case study is presented to examine the failure modes with respect to several parameters, such as excess pore pressure, seepage flow, seepage force, failure areas and stress path in the seabed. The conclusions obtained from this study were as follows ; () the thickness of a permeable seabed affects the pore pressure and effective stress response to ocean waves and the failure mode of the seabed, (2) either a liquefaction or shear failure, or both, occur in the seabed, even in the saturated seabed, (3) the Mohr-Coulomb's failure criterion, when combined with elastic stresses, can not be employed to estimate the liquefaction failure in the seabed, () the liquefaction can be evaluated by a criterion in terms of the excess pore pressure, (5) The liquefied zone in the seabed is significantly different from the shear failure zone. The shape beneath the seabed surface for the former is almost identical to the contour where the upward seepage flow is concentrated.

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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 M-2 mixing ratio δ, and the 0-2 mixing ratio μ_k are obtained for 818. keV +→2₁⁺ transition to be δ=−+0.26, and μ_k≤6.×10−

4

respectively. The

E

2 branching ratio

B

(

E

2;

2₂

+→0_g⁺): (2; +→2₁⁺): (2; +→0₁⁺) is determined to be 0.0158:.0:5.86.

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In the 1993 Kushiro-oki Earthquake of Richter magnitude ., simultaneous recording of earthquake motions was successfully made at the ground surface and at a depth of 77 meters in a dense saturated sand deposit. The peak horizontal acceleration was 0.47 g on the ground surface and 0.21 g at a depth of 77 meters. The acceleration record at the ground surface showed a distinctive ground response, which consisted of a cyclic motion having a period of about .5 seconds overlain by a spike at each peak of the motion. In order to study the mechanism of this peculiar ground response, effective stress analysis was conducted on the dense saturated sand deposit. The model used for this study was a strain space multiple mechanism model, which takes into account the effect of principal stress axis rotation. The recorded earthquake motion at a depth of 77 meters was used as the input earthquake motion for the analysis. Sampling after in-situ freezing was done in order to evaluate the properties of the sand. The results of the analysis indicated that the observed ground response was due to the effect of dilatancy of sand, which plays a significant role in the response of the dense saturated sand deposits during strong earthquake motions.

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The paper examines how well standard sources of impact sounds(bang-machine, A-ball, NF-ball, new rubber ball)imitate real impact sounds(human jumping and hopping).The compared sounds were described from psychoacoustic point of view.At the same time similarities between the impact sounds were judged in the psychoacoustic experiment.Results were compared with the existing standards expressed in F- and S-maximum sound levels:L_{A max, F}, L_{A max, S} and sound exposure level L_AE.

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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 M-2 mixing ratio, δ², and the dimensionless ratio X of 0-2 mixing of the 586. keV transition are obtained to be δ²≤0.16 and 0.034≤X≤0.038, respectively. The 2 branching ratio (2; +→0_g⁺): (2; +→2₁⁺): (2; +→0₁⁺) is determined to be 0.023 : .0 : 5.6.

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In this paper, centrifuge shaking table tests were conducted in order to understand the performance of seawalls during a seismic event. The model tests showed that the displacement of the caisson was much affected by the seaward shear deformation of the sand seabed beneath it during shaking. It was also confirmed that an armored embankment played an important role in the displacement of the caisson during shaking. Based on these test results, a two-dimensional DEM-FEM coupled analysis method was newly developed to numerically predict the deformation of seawalls covered with armored embankments during earthquakes. The movements of the armor units were calculated by DE analysis and deformations of the caisson, rubble mound, sand seabed and backfill were calculated by FE analysis considering the non-linearity of the soil materials based on the effective stress. Dynamic interaction was taken into account by delivering the nodal displacements of the finite elements or the nodal forces converted from the contact forces through the imaginary distinct elements defined at the boundaries between the DE and FE domain. The applicability of this method to the prediction of the deformation of seawalls was verified through numerical simulations of the centrifuge model test.

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Seismic records obtained from a seismometer array located in downtown Tokyo Japan for about ten years were inversely analyzed to estimate the dynamic soil parameters. Due to the illposed nature of the problem, the simple and often used "least square method" does not properly estimate the parameters. The Extended Bayesian Method combined with the Akaike Bayesian Information Criterion was introduced to overcome this difficulty. The results obtained were compared with dynamic triaxial test results obtained at the time of the seismometer installation. The shear moduli agree quite well with the estimated results, however the damping ratios estimated are slightly higher than the ones obtained in the laboratory.

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This paper concerns the stability against overturning of the caissons on rubble mound subjected to wave loading. A theoretical discussion is first made of the stability of a leaning caisson during wave loading, as a single degree-of-freedom system. The expression for the lower bound of driving moments sufficient to overturn a given caisson is derived. A review is then made of the damages induced to a composite breakwater, which consisted of two adjoining Stretches and C with slightly different sizes of caissons. Attention is called for the observation that most of the caissons in Stretch were overturned, whereas no caissons in Stretch C were brought into overturning. This fact is examined in detail in the light of the theory of overturning, making it possible to estimate the destructive wave heights that are compatible with the observed patterns of damage in Stretches and C of the composite breakwater.

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  The distribution of sarcophytol-A in the Sarcophyton genus was investigated in seven samples belonging to S. glaucum (3 samples), S. infundibulifurme (2 samples), S. crassocaule ( sample) and S. trocheliophorum ( 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 paper illustrates theoretical and experimental procedures adopted to characterize the seismic response of earth dams by performance-based criteria. The study refers to a real case, the Camastra Dam, a zoned earth dam with vertical clay core, placed in a highly seismic zone of Southern Italy. At first, the analysis objectives have been identified along with the physical quantities needed to achieve them for characterizing dam seismic performance. A theoretical approach, consistent with the identified analysis objectives, has been later selected. The adopted approach is based on continuum mechanics and accounts for coupling between soil skeleton and pore water phase. It is also able to describe the main features of soil response under cyclic loading conditions since it implements an advanced constitutive law for the soil skeleton. Big effort has been paid to the mechanical characterization of the dam materials. In addition to data coming from the interpretation of the laboratory tests performed at the time of dam construction, in situ tests (SASW, Down Hole, DMT) have been recently carried out on the embankment and foundation soils and interpreted consistently with the requirements of the selected theoretical model. Preliminarily, the static stages of the dam lifetime have been numerically simulated to reproduce the behaviour observed in terms of cross-arm settlements and pore water pressures, in order to obtain or verify some soil parameters and initialize the state variables for the simulation of the seismic stages. A seismological study of the dam site provided the expected seismic scenarios in terms of time histories of acceleration, needed as input for the dynamic analyses. The seismic response of the Camastra Dam was finally investigated and discussed in the light of performance-based criteria.

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A crucial matter related to roads in seismic areas is to ensure viability during the post-seismic stages, especially if the road represents an important or unique way to reach towns that may be potentially hit by strong earthquakes. Verification of road viability under seismic actions requires not only safety assessment of the failure mechanisms which may jeopardize single road components (embankment, viaduct, bridge, etc.) but also evaluation of performance. Viability of a road may be compromised by an unsatisfactory response of road embankments. The vehicle flux may be, in fact, inhibited or reduced if a road embankment suffers global instability mechanisms or significant permanent displacements mainly at the contact with structural elements (.g., viaducts, bridges) that do not move significantly. In this case the embankment permanent displacements turn out into steps or separations. The paper accounts for the different stages followed to study the seismic performance of the road embankments located along a sample road branch of about 5 km. Preliminary activities consisted in characterizing the geological area of the sample road, in selecting the potentially vulnerable embankments and in carrying out in-situ investigations to properly characterize the physical and mechanical properties of the embankments and foundation soils. A seismological study of the sample area was performed in order to characterize the reference seismic actions needed for the numerical analyses. The seismic response of the embankments was evaluated by a pseudo-dynamic approach and an advanced dynamic model. In the latter, the equations describing dynamic equilibrium and compatibility were merged with an elastoplastic combined-hardening constitutive law that properly models soil response under cyclic loads. The embankment's seismic performance was predicted in terms of permanent settlements at the embankment top surface versus the peak acceleration of the reference input motions.

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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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The phase diagrams of the Ni-Mo- and Ni-W- ternary systems in the region of less than 50mol% were constructed by thermodynamic calculation, based on the data obtained by thermodynamic measurement of the related materials. We found three ternary eutectic points and three or two ternary peritecto-eutectic points as follows:
:L (1365K, 71.5mol%Ni-6.0mol%Mo-.5mol%)=(Ni)++
:L (1355K, 62.5mol%Ni-2.5mol%Mo-30.5mol%)=++
:L (1445K, 42.0mol%Ni-30.6mol%Mo-10.3mol%)=(Ni)+NiMo+
:L (1812K, 34.9mol%Ni-42.3mol%Mo-.mol%)+MoB=+
P₂:L (1633K, 42.3mol%Ni-40.mol%Mo-17.3mol%)+Mo=+
P₃:L (1812K, 53.5mol%Ni-33.mol%Mo-12.mol%)+Mo=NiMo+
:L (1622K, 51.0mol%Ni-31.6mol%W-17.mol%)=(Ni)+W+
:L (1260K, 71.0mol%Ni-.0mol%W-.0mol%)=(Ni)++
:L (1291K, 65.mol%Ni-.mol%W-29.mol%)=++
:L (2115K, 23.mol%Ni-43.mol%W-33.mol%)+WB=+
P₂:L (1657K, 48.9mol%Ni-33.mol%W-18.0mol%)+=W+
The calculated phase diagrams are expected to be useful for the development of new Ni-based heat-, corrosion- or wear-resistance alloys.

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Based on the methods previously presented by the authors (Yasuhara et al., 1992, 1994, 1996) for predicting the degradation in strength and stiffness of soft clays in the course of cyclic loading, a methodology has been developed to estimate the cyclic loading-induced settlements. The method also includes not only immediate settlements but also post-cyclic long-term settlements due to dissipation of cyclically induced excess pore pressures in soft soils. The simplified formulae included in the proposed methodology are given as functions of the amplitude of cyclic-induced excess pore pressure normalized by the confining pressure, u/p'_c, plasticity index I_p and factor of safety against bearing capacity failure, F_s. The calculations of cyclic-induced settlements were conducted for soft soil deposits with different index and geotechnical properties. The results calculated using the proposed methodology are presented in the form of a design chart to give the settlement versus normalized excess pore pressure ratio relations including the effects of the plasticity index and safety factor for bearing capacity. An example of the calculated results using the proposed procedure for the earthquake-induced settlements of embankments founded on soft clay, is presented to demonstrate the practicality of the method for design at fields.

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Shaking table tests were performed to clarify the settlement in liquefied loose sand of a new foundation incorporating top-shaped concrete blocks. In the tests, blocks of half scale were installed as they are in practice, by using a crusher-run, a lattice of iron rods and iron bars. Shaking table tests were also conducted on foundations with two differently shaped concrete blocks to investigate the effectiveness of the three foundations in reducing settlement. One was a T-shaped concrete block, or a disk-shaped concrete plate with a leg. The other was a conical concrete block without a leg. The results of shaking table tests showed that the foundation with the top-shaped concrete blocks was most effective in reducing the settlement among the three types of foundation. FEM elastic analyses were performed to compute the stress distributions in the models and in-situ ground when the top-shaped concrete blocks were applied and to confirm whether liquefaction resistance of the sand layer below the foundation is large. Moreover, the factor of safety against liquefaction, F_L was evaluated in in-situ model ground, in order to compare with sensitivities against liquefaction in the ground without countermeasures and with top-shaped concrete blocks. For the liquefaction analyses, shear stress in the ground during an earthquake was estimated by dynamic analyses using the SHAKE computer program.

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