Two new polyacetylene compounds (, 6, 12)-1-acetoxy--isovaleryloxytetradeca-, 6, 12-trien-, 10-diyn-14-ol (B), and (, 6, 12)-1-acetoxy--(2-methylbutyryloxy)tetradeca-, 6, 12-trien-, 10-diyn-14-ol (C) have been isolated along with (, 6, 12)-1-acetoxy--senecioyloxytetradeca-, 6, 12-trien-, 10-diyn-14-ol (A) from Atractylodes Rhizome (Karabyakujutu). The structures of these compounds were determined on the basis of their spectral data.

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Chemical synthesis of (, 24R)- and (, 24S)-1, 24-dihydroxy--vitamin has been achieved starting with the commercially available dinorcholenic acid acetate. Synthesis involved introduction of the 1-hydroxy group by a reduction of the 1, 2-epoxide generated by epoxidation of the 1, , 6-trien--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 1-phenyl-1, 2, -triazoline-, -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 , 7-dienes were irradiated and the corresponding vitamin compounds isolated. Nuclear magnetic resonance was used to identify individual isomers. The (, 24S)-1, 24-hydroxyvitamin compound bound equally well to the chick intestinal cytosol receptor as 1, 25-dihydroxyvitamin , while the 24R-isomer was approximately ten times less active. In vivo, both isomers were less active than 1, 25-dihydroxyvitamin ; however, the 24S-isomer was considerably more active than the 24R-isomer approaching the activity of 1, 25-dihydroxyvitamin .

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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 1-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 1 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 performance of single pitch and multi pitch screw anchors during the application of installation torque is presented. An experimental testing program was conducted using five models of screw anchors with different geometry. The effect of the shape of the screw element, sand properties, and installation depth on the required installation torque value was examined. A theoretical model was developed from which the required installation torque value can be calculated in terms of the influencing factors. The required installation torque can be determined in terms of the ultimate uplift resistance calculated from any of the available theories. Based on the actual installation torque value measured in the field, the anticipated pullout capacity can be back calculated from the present theory. A comparison between theoretical and experimental results showed good agreement. Also, good agreement was observed when the present theoretical results were compared with the available field results reported in the literature.

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The syntheses of (S)-13-hydroxy-(2, , )-tetradecatrienoic acid (1) and (2, , Z-tetradecatrienoic acid (2) were carried out by using the Wittig reaction as the key step. The asymmetric center at C-13 and the double bond between C- and C-9 for natural compound 1 were reconfirmed as being of (S) configuration and , respectively. The relationship between the structure of the unsaturated hydroxy fatty acids and their inhibitory effect on the growth of lettuce was investigated.

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We screened the differentiation-inducing activities of 39 mushroom extracts from Akita prefecture, Japan, on the mouse osteoblastic cell line, MCT-1. Sixteen phosphate buffered saline (PBS), boiled PBS, 14 ethanol and 12 methanol extracts induced alkaline phosphatase (ALP) activities, an indicator of MCT-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-7,-diene-,,6β-triol (1). 1 induced ALP activities of MCT-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 MCT-1 cells by 1, ergosterol (2), ergocalciferol (), cholesta-,,6β-triol (), 7-dehydrocholesterol () and cholecalciferol (6) were tested. The enzyme activities of MCT-1 cells were increased .0-fold by 10 μM 1 and 2.-fold by 10 μM . However, 2, , and 6 did not induce MCT-1 cell ALP activity at 0.1—10 μM. These results suggested that the OH groups at C- and/or C-6 of 1 and played an important role in their differentiation-inducing activities on MCT-1 cells. Furthermore, 1 suppressed induction of MCT-1 cell apoptosis by serum starvation.

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In the seismic analysis of pile foundations the soil is often assumed to be an elastic material and the pressure at the soil pile interface is not limited during the analysis. This may result in a considerable error, as the computed pressure from an elastic analysis may go well beyond the ultimate lateral pressure of real soil. In fact, significant yielding at the soil-pile interface has been observed during real earthquakes, and also in laboratory tests. The yield zone is usually near the ground surface where the effect of inertial force due to the superstructure is higher. This yielding redefines the pile response, and in general cannot be ignored. In order to examine the effects of soil yielding on the internal pile response during earthquakes an approximate analysis is described in this paper which is an extension of a static method developed by the second author (1982) for the analysis of piles subjected to lateral soil movement. This method is then used to investigate the effects of soil yielding on the internal response of piles through a comparative study in which real earthquakes are used. It is shown that for strong earthquakes and heavily loaded piles the soil yielding may considerably increase the amount of maximum pile moment developed in the pile. A marked difference in the effects of yielding on the pile moment and shear is observed and discussed.

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The interaction between a penetrating shaft and the surrounding soil media under impact loading is a frequently encountered phenomenon in geotechnical engineering. Examples of such dynamic soil/shaft interaction would include dynamic pile driving, standard penetration testing (SPT), and dynamic driven rod test. Presented in this paper is a novel approach, based on the principle of dynamic system identification, which enables identification of dynamic soil-pile interaction model parameters. The analytical transfer function, relating the output stress wave forms to the input stress wave forms in the soil/shaft system, is derived using the Laplace and Fourier Transform techniques and the one-dimensional wave propagation theories. A numerical solution algorithm based on a variation of gradient method is coded into a micro-computer based program to solve the frequency-dependent soil-pile interaction parameters (Smith model) : soil damping and soil spring stiffness. To further reduce the amount of computational effort required in the solution of the frequency-dependent dynamic soil properties, it is suggested that the solution be obtained for the first-mode natural frequency of the measured stress waves. The results obtained from this simplified solution algorithm, when compared with both numerical simulations and controlled laboratory tests, are reasonably acceptable. The proposed parameter identification technique offers a viable alternative data interpretation procedure for deducing pertinent Smith model parameters used frequently in pile driving analysis.

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A comparative study of the static and dynamic response of a slope is carried out, using the large deformation theory of the updated Lagrangian formulation and the conventional infinitesimal theory. In the static analysis, a strength reduction method proposed by one of the authors is used to evaluate the safety factor of the slope. It is found that by the large deformation theory, the safety factor is larger than that calculated by the infinitesimal theory, and this difference becomes large along with the reduction of elastic modulus. In the dynamic analysis, it is observed that the large deformation theory gives smaller sliding displacement and larger response acceleration than the infinitesimal approach. It is concluded that in many cases the large deformation approach gives more adequate solutions.

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Six full-length cDNAs encoding pig cytochrome P450 (CYP) enzymes, CYP1A1, CYP2A19, CYP2B, CYP2C33v, CYP2C49, and CYP21, were isolated and sequenced. The cDNA sequences of pig CYP1A1, CYP2A19, CYP2B, CYP2C49, and CYP21 showed high similarity to human CYP1A1 (.%), CYP2A13 (88.6%), CYP2B6 (.1%), CYP2C18 (.%), and (.%), respectively, and pig cDNA showed high similarity to rat CYP2C23 (79.2%). Reverse transcription-polymerase chain reaction (RT-PCR) assays revealed hepatic gene expression of all these pig CYP enzymes: the order of expression was and > CYP2C49 > CYP1A1 and CYP2A19 > . In the kidney, the gene was expressed at the same level as in the liver, but the CYP1A1, CYP2A19, and genes were expressed at lower levels than in the liver. Little renal gene expression of CYP2C49 and CYP21 was observed. We revealed for the first time the full-length cDNA sequences encoding pig CYP1A1 and five CYP enzymes belonging to the CYP2 gene family, thus making it possible to examine the gene expression levels of these CYP enzymes in pig tissues by RT-PCR.

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Static characteristics of two different structured InAlGaAs/InAlAs superlattice avalanche photodiodes (SLAPDs) cooled by liquid nitrogen were evaluated at a wavelength of 1. μm. The dark current of the SLAPD having a thick superlattice layer of 0.504 μm was ×10^-13 A. This was successively reduced by four orders of magnitude compared to that of the thin layer SLAPD of 0.231 μm at a breakdown voltage of around 20 V. The thickened layer was effective in suppressing tunneling dark current. An output current of 1.7×10^-12 A at a bias voltage of 15 V was measured for an optical input with a wavelength of 1. μm and a signal power of 1×10^-12 W. This showed a sharp distinction from the dark current.

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Two new vitamin analogues, 1α-hydroxy-24, 24-dimethyl--dehydrovitamin (13) and 1α, 25-dihydroxy-24, 24-dimethyl--dehydrovitamin (17), which are blocked for 24-hydroxylation by the methyl groups, were synthesized from 1α, -bismethoxymethoxypregn--ene-20Scarbaldehyde (6) by using the orthoester Claisen rearrangement for construction of the carbon skeleton of their side chains. These compounds (13 and 17) elicited a rise in serum calcium, but not in serum inorganic phosphorus in rats. In a bioassay for alkaline phosphatase, they were found to show much weaker activity than 1α-hydroxy vitamin ().

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The behavior of the soft clay grounds subjected to repeated loading is different from that subjected to sustained loading. The difference in settlement between these two loading patterns should be due to secondary compression over a long period of time. Consequently, soft clay grounds subjected to repeated loading tend to be more compressible than those subjected to sustained loading. Therefore, it is necessary for engineers to predict post-construction settlements under repeated loading. In this respect, the preloading is considered to be promising as a countermeasure to reduce the settlement of clay under repeated loading as well as under sustained loading. The effect of preloading on post-construction consolidation settlement of soft clay subjected to repeated loading after removal of a part of preload is investigated in the present paper. It has become clear that the settlement of a clay sample after preconsolidation is mainly affected by the amount of preload, the degree of consolidation due to the preload, the amount of permanent load and the amount of repeated load after removal of preload. The calculated settlement versus time relations using a method to estimate the amount of consolidation settlement of soft clay grounds subjected to repeated loading after removal of preloading were compared with the observed degree of consolidation as parameters of the intensities of preload and repeated load.

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ドコサヘキサエン酸エチル (-DHA) の大量精製方法の確立を目的とし, 固定化Rhizomucor mieheiリパーゼでマグロ油由来のエチルエステル (-DHA 55; -DHA含量, 55mol%) をラウリルアルコール (LauOH) でアルコリシスした。固定化リパーゼを充填したカラム (.0g; ×63mm) に-DHA/LauOH (1 : 7, mol/mol) の混液を30℃, 10mL/hの流速で負荷した。その結果, エステル交換率は58%に達し, エチルエステル画分の-DHA含量は87mol%まで上昇した。この固定化酵素リアクターを150日間連続運転すると, エステル交換率は48%まで低下したものの, -DHA含量はほとんど低下せずmol%まで上昇していた。カラムから溶出した反応液中のエチルエステルは薄膜蒸留により収率よく回収できたが (%), この画分には2.wt%のLauOHと6.wt%のラウリルエステルが混在していた。このうち, ラウリルエステルは尿素包括により完全除去することができた。一連の精製操作により, -DHA55に含まれていた-DHAの52%が回収でき, -DHA含量を88wt%まで高めることができた。

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In the 1993 Kushiro-oki Earthquake of Richter magnitude 7., 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 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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Elastic wave propagation in saturated soil is investigated in order to grasp the frequency dependent wave propagation property of actual soil. First, a closed form solution of Biot's equation is derived under a one-directional wave propagation condition. Then, the frequency dependent properties of waves in various soils such as clay, silt, sand, gravel and soft rock are computed and discussed. The behavior is shown to be classified into three states : low frequency, high frequency and transient. Properties hardly change in the low and high frequency states. The degree of saturation is shown to hardly affect the shear wave property, but it greatly affects the dilatational wave property, especially in a highly saturated condition. Permeability hardly affects the properties at low and high frequency states, but it does change the frequency range of the transient state. Next, the applicability of Biot's formulation is examined and the high frequency state derived from Biot's equation is shown to be valid when permeability is larger than that of silt. Finally, it is shown that various mechanical properties can be evaluated using the frequency dependent characteristics of the wave, some of which are difficult to measure in situ with conventional tools.

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