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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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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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), 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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When a mudflow moves down a slope, the gravity induced shear stress, τ, is opposed by the combined effect of the undrained shear strength, c_u, of the mud, and its viscosity, η, which is associated with the velocity gradient in the mudflow, dv/dy. In equation form this can be expressed as : τ= c_u+η(dv/dy). The resistance provided by the mud involves the contribution of both c_u and η. For an understanding of the mobilization mechanics of mudflows, one needs then these two parameters. This study describes two methods that can be used to determine these parameters. The c_u of the muds is measured using a cylinder-strength meter devise. The technique associated with this devise consists in lowering a cylinder of known dimension and weight into a mud sample, measuring the depth of penetration of the cylinder into the mud, and calculating the strength, c_u, of the mud required to support the solid cylinder at that depth. The c_u of the mud is calculated using Sokolovski's theory designed to calculate the indentation pressures developed by a Tresca plastic when a cylinder penetrates it. The determination of the viscosity, η, of the mud is obtained from either the velocity measurements of the free surface of the mudflow, or from the difference between the velocity of the free surface of the mudflow and its velocity at the interface between the mudflow and the surface on which it moves. The viscosity η is obtained from a relationship that relates these velocities with η.

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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 ; (1) 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, (4) the liquefaction can be evaluated by a criterion in terms of the excess pore pressure, () 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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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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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-C 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 ±.1Vp-p input signal at each input terminal in the pseudodifferential configuration. The LPF including an output buffer dissipated 60mW in the case of a 1.2V supply. Wide spurious-free dynamic range (SFDR) characteristics were confirmed up to high frequencies.

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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 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 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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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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Based on the assumption that an inward- or outward-directed flow perpendicular to a slope exists, this paper describes an experiment and test results. The results are compared with both traditional continuum and single-grain theories presented for the relationship between hydraulic gradient and slope angle. For the case of outward flow, the continuum theory governs the failure mechanism of the Shirasu talus deposit. The single-grain theory controls the failure process for inward flow.

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Among the rivers damaged by the earthquake, two most severely damaged along the Yodo-gawa River are described. In the left levee, the settlement exceeded 2 m for a length of 1.4 km, with a maximum settlement of 3 m. Sand boils were observed extensively on the ground surface near the damaged dikes. Holocene sandy soil with an SPT N-value of 10 or less existed in the upper part of the subsoil profile. These facts indicate that liquefaction of the soil was the major cause of the embankment damage. The cyclic stress ratio required to cause liquefaction was .30 as determined from cyclic triaxial tests on undisturbed samples.

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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 .47 g on the ground surface and .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 1. 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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