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 () 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.

抄録全体を表示

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.

抄録全体を表示

The saponin fraction from the seeds of the tea plant [Camellia sinensis (L.) O. KUNTZE (Theaceae)] was found to exhibit potent protective effects on ethanol- and indomethacin-induced gastric mucosal lesions in rats. Five new triterpene saponins, theasaponins (1), (2), (), (), and (), were isolated together with 11 known saponins from the saponin fraction. The chemical structures of 1— were elucidated on the basis of chemical and physicochemical evidence. Among the isolated saponins, theasaponins (), (), and () and assamsaponin C (10) showed an inhibitory effect on ethanol-induced gastric mucosal lesions at a dose of .0 mg/kg, p.o. and their activities were stronger than that of omeplazole. With regard to the structure–activity relationships of theasaponins, the following structural requirements for a protective effect on ethanol-induced gastric lesions were suggested; 1) the 21- and/or -acyl groups are essential for the activity, 2) acetylation of the 16-hydroxyl group reduce the activity.

抄録全体を表示

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), 8 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-,-diene-,,-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-,,-triol (), -dehydrocholesterol () and cholecalciferol () 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 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- 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.

抄録全体を表示

Two new polyacetylene compounds (, , 12)-1-acetoxy--isovaleryloxytetradeca-, , 12-trien-8, 10-diyn-14-ol (B), and (, , 12)-1-acetoxy--(2-methylbutyryloxy)tetradeca-, , 12-trien-8, 10-diyn-14-ol (C) have been isolated along with (, , 12)-1-acetoxy--senecioyloxytetradeca-, , 12-trien-8, 10-diyn-14-ol (A) from Atractylodes Rhizome (Karabyakujutu). The structures of these compounds were determined on the basis of their spectral data.

抄録全体を表示

Background

The differences in conditions of enteric-coated acid-labile drug release and absorption between healthy subjects in bioequivalence studies and gastrointestinal patients in clinical practice can lead to significant differences in gastric stability of original PPIs and generics. Thus, pathologic duodenogastric reflux (PDGR) and the pH increasing within PPIs administration still remain unaccounted for.

Methods

Two-stage modified comparative dissolution testing of original omeprazole (OO) and four generics (G1;2;

;) was performed. At first, we moved drugs from solution with pH 1.2 (1.2±0.05) to pH .0 (.0±0.05) and measure concentration of omeprazole in solution by high-performance liquid chromatography. According to our self-developed formula, pH exposure time of resistance to PDGR for omeprazole is minutes, i.. the active substance should not be released within minutes at pH . The exposure at the second stage was conducted with pH (.0±0.05), that imitated gastric pH after PPI administration. And then we also moved drugs to pH with the subsequent measurement of omeprazole concentration.

Results

Omeprazole concentrations after

, 10, 15, 20, 30, 45, 60 minutes in pH solution at the first stage were different for OO and generics. For OO, these values were ,±0,%; 41,±,0%; 62,8±,0%; 79,±2,9%; ,±2,9%; ,±2,9%; 80,±,%; for Generic1 - 0; 49,±9,9%; ,8 ±2,8%; 90,±,%; , 2±2,2%; 87,±2,0%; 85,9±1,1%; for Generic2 - 0; 30,±,%; 66,±8,2%; 76,±,%; ,8±,%; 86,0±,%; 84,±,%: for Generic - 80,8±,%; ,±1,9%; , 8±,2%; ,±2,%; ,9±2,1%; ,1±2,0%; ,0±2,%; for Generic - ,±1,%; 84,±0,8%; 84,2±1,2%; , 9±0,9%; ,9±0,9%; ,9±0,9%; ,8±1,1%, respectively.

An analysis of the omeprazole concentration in pH

solution at the second stage revealed the following parameters after the same time: for OO - ,±0,%; 40, ±,0%; 62,8±2,0%; 80,0±,1%; 85,±2,9%; ,8±,%; 80,9±,%; for Generic1 - 0; 67,0±,8%; ,±2,%; 91, 9±,%; ,1±1,%; ,±1,%; 87,8±1,2%; for Generic2 - 0; 42,2±,%; 75,1±,%; ,0±,0%; ,±,2%; , ±1,%; 87,9±1,0%; for Generic - 85,±0,%; 85,±0,%; 84,±0,9%; ,±,0%; 84,±0,%; 84,±0,%; 84,±0,%, respectively. Generic release and degradation were completely realized at pH .

Conclusion

Decreased gastric stability of Generic

and Generic makes PDGR and inhibited gastric acid secretion due to PPIs administration the potential causes of decreased enteric-coated acid-labile drugs stability.

抄録全体を表示

The association between apolipoprotein (Apo-) polymorphism and the response of plasma cholesterol to dietary therapy (cholesterol intake of less than 300mg/day) was investigated for about 8 weeks in 208 nonfamilial hypercholesterolemia patients (/ 161, / 47). The baseline lipoprotein concentration and the intake of energy and lipids were not significantly different between subjects with / and those with / phenotypes. After the dietary therapy plasma total cholesterol and low density lipoprotein cholesterol were significantly decreased in both phenotype groups (p<0.05). The patients with / had significantly smaller reductions of LDL-C than the patients with /. The changes of LDL-C showed a significant difference between the patients with / and / by the Kruskal Wallis test (p=0.041). The presence of / predicted the degree of cholesterol reduction following dietary therapy.

抄録全体を表示

A mixture of two monoterpenes was obtained as the opisthonotal gland secretion from unidentified Histiogaster sp. A096 (Acari: Acaridae), and their structures were elucidated to be ()-dehydrocitrals[(2,)- and (2Z,)-,-dimethyl-2,,-octatrienals] by GC/MS, GC/FT-IR, UV and ¹H-NMR spectra. Both isomers of ()-dehydrocitral prepared by syntheses in steps from -methyl-2-butenal with 34.2% yields (based on the ylide) were separated by column chromatography into the (2,)- and (2Z,)-,-dimethyl-2,,-octatrienal. Mass spectra together with GC retention times of the purified natural ()-dehydrocitrals were identical with those of synthetic (2,)-,-dimethyl-2,,-octatrienal and (2Z,)-,-dimethyl-2,,-octatrienal. The geometry at the 2-C position of both synthetic ()-dehydrocitrals was confirmed by NOESY analyses. This is the first identification of ()-dehydrocitrals from the animal kingdom.

抄録全体を表示

The pseudo-static analysis has been used in engineering practice to simplify the computation of the upper limit of a slope under seismic load. In this paper, the upper bound technique of limit analysis of perfect plasticity is used to determine the bearing capacity of a foundation near a down-hill slope. In this analysis (Chen et al., 1969; Chen, 1975), a logarithmic spiral rapture (Abdul-Baki et al., 1970; Sawada et al., 1984) is assumed to start at an edge of the loaded area far from the slope. A landslide is assumed to be of rigid body type with the inertia force acted at its center of gravity. The collapse state is reached when the rate of kinematic energy of the landslide together with the load is equal to the rate of dissipation of internal energy along the sliding surface. This energy balance leads to the equation of ultimate load with several parameters. The optimized numerical rcsults with respect to these parameters are compared with those by Kotter's method (Yamaguchi, 1959) and those obtained by the slice method.

抄録全体を表示

A method for analyzing the uncertainties involving the use of empirical relationships in design is developed. It is applied to evaluate the reliability of the relationship s_u(mobilized)=(measured), whereby the pertinent uncertainties are analyzed using extensive laboratory and field observed data. On the average, the relationship s_u(mobilized)= (measured) is unbiased and the error implicit in the relationship is about 15%. When cone values are used to infer s'_p, additional uncertainties on the mobilized undrained strength will incur resulting mainly from the calibration uncertainty between σ'_p and the cone values. Alternatively, vane tests may be performed to infer the mobilized strength using Bjerrum correction factor. Results show that uncertainty level associated with using the vane tests is smaller than that using the cone values, provided that similar scatter is observed between measured vane and cone values at a given site. However, prediction of the mobilized strength is even more accurate if direct measurements can be made on the preconsolidation pressure. The proposed probabilistic method also assesses the benefit of additional tests besides comparing the accuracy of using various soil parameters for predicting mobilized undrained strength. Such information is essential for planning cost-effective site characterization program.

抄録全体を表示

The leaning tower of Pisa is a famous historical structure, especially in the field of soil mechanics. In this paper, the historical development of the inclination is reconstructed considering that a ground failure took place after each of the three construction phases. Model tests (scale 1 : 130) were carried out in order to predict that the tower will fail definitely, i.. without any further disturbances, at an angle of inclination of .°, which is dramatically close to the actual value of .°. The estimated probability of failure rises very quickly with an increase in the angle of inclination. Conservation of the tower should be done therefore with utmost caution.

抄録全体を表示

This paper presents reinforcing mechanisms and a method for analyzing reinforced earth structures. The reinforcing mechanism presented is divided into two stages, a fixed slip surface and an arbitrarily selected slip surface. The mechanism is studied through direct shear tests and plane strain compression tests including some geotextiles. The reinforcing materials considered in this paper only have tensile strength. The authors have already proposed a method called Generalized Limit Equilibrium Method (GLEM) for analyzing stability problems. The validity of the method has already been shown in previously published papers. In this paper, the method is extended to carry out a stability analysis for reinforced earth structures. Finally, large scale model tests for the bearing capacity of foundations on reinforced slopes were carried out to investigate the validity of the proposed reinforcing mechanism and the analytical method. Through comparisons of observations of experiments and results of the analytical method, the validity of the present work is demonstrated.

抄録全体を表示

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 -dB frequency bandwidth, group delay ripple, rd-order distortion, and rd-order input intercept point (IIP) were 200MHz, 2.2%, ≤ -55dB with a 100MHz input, and +10.dBm, respectively, all with a ±0.1Vp-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.

抄録全体を表示

Results of model loading tests on dense sand were reviewed to assess the variation in bearing capacity factors N_γ and N_q relative to the width of the foundation base. Consequently, it is confirmed that N_γ decreases non-linearly with increase in the width of foundation base and that N_q decreases more sharply than N_γ does as the width increase. It is also found that N_q decreases as the ratio of burried depth to the width increase. The cause of decrease in N_γ or N_q with increase in the width is regarded to be the rise of stress level which induces lowering of the angle of internal friction φ and volume reduction in the bearing sand by compression.

抄録全体を表示