Some existing analytical methods which have been used in geotechnical engineering are modified to handle the shear strength reduction with time due to softening in fissured, over-consolidated clays and mudstones. These are limit equilibrium analysis of slope stability, calculation of earth pressure and calculation of stress and displacement around a tunnel. The softening effect is incorporated in these analyses using the failure criterion and the time-dependent strength parameters proposed previously by the authors. Examples are presented which emphasize the importance of appreciating the softening effect in analyses and further illustrate that the effect of shear strength reduction with time due to softening could easily be captured with existing analytical methods.

抄録全体を表示

背景と目的：ステロイド性骨粗鬆症は，積極的な治療介入が必要とされる．その第一選択薬はビスホスホネート製剤（以下ビス）であるが，近年，デノスマブ（以下デノス）も注目を浴びている．ステロイド性骨粗鬆症の骨密度に対する両者の効果を比較検討した．

方法：ステロイド性骨粗鬆症の管理と治療ガイドライン：2014年改訂版の薬物療法開始の基準を満たした患者を対象とした．無治療群（N群）と，治療介入群として当初よりビスで治療したBB群，ビス後デノスに変更したBD群，デノスで治療したDD群，デノス後ビスに変更したDB群を抽出し，ステロイド投与を開始した時，ステロイド性骨粗鬆症に対する治療を開始した時または薬剤変更から

カ月後の腰椎，大腿骨頚部と大転子部の骨密度を測定し，それらの変化を統計学的に比較検討した．

結果：149例が抽出され，その内訳は，N群48例，BB群24例，BD群

例，DD群21例，DB群34例であった．治療開始時または薬剤変更からカ月後にBD群を除くすべての治療介入群で腰椎の骨密度が上昇した．大腿骨の骨密度は，BD群において薬剤変更後に上昇に転じた．

考察：デノスにはビスと同様の骨密度上昇効果があると考えられた．

結論：デノスは，ステロイド性骨粗鬆症治療の第一選択薬となり得る．

抄録全体を表示

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.

抄録全体を表示

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.

抄録全体を表示

The main objective of this paper is to compare safety factors obtained from Morgenstern-Price, Janbu and Spencer methods with the factors calculated from the modified variational approach (Leshchinsky and Huang, 1992a). Such comparison is essential since there is no mathematical proof that the variational analysis indeed yields a minimum and thus, physically produce significant results. The safety factors compared well, indicating the variational analysis is on a par with acceptable existing rigorous methods. Availability of a user-friendly computer code may make the variational analysis useful to practicing engineers. However, its greatest potential at the moment is in 3-D applications; i.., unlike other methods, its extension to 3-D is straightforward.

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, 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 3.0-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 0.1—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.

抄録全体を表示

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.

抄録全体を表示

A procedure for limit equilibrium slope analysis based on a realistic consideration of the mobilized interslice shear forces is presented in this paper. This new approach ensures that solutions are kinematically admissible and the possibility of convergence problems, often associated with numerical solutions, is minimized. The proposed approach recognizes the importance of slip surface geometry in estimating interslice shear forces whether vertical or non-vertical slices are used in a limit equilibrium analysis. Illustrative examples are presented and the results shown to be reasonable. The calculated factors of safety based on the new method compare very well with values based on recognized methods of analysis. Yet the method is more direct and enables a proper visualization of the transfer of mobilized normal and shear forces through a sloping soil mass above a potential slip surface. The method also gives consistent results with non-vertical slices even if the shape of non-vertical slices is varied.

抄録全体を表示

A new analytical method is proposed for determining the inextensible grid reinforcement pullout resistance and pullout force/pullout displacement curve by using basic backfill soil and grid reinforcement properties. The pullout skin friction resistance/pullout displacement relationship is simulated by linear elastic-perfectly plastic model. A hyperbolic model has been proposed to represent the pullout bearing resistance/pullout displacement relationship in which the maximum bearing resistance of a single bearing member is determined using a new bearing capacity equation proposed in this paper. The influences of the grid bearing member spacing ratio, S/D, the bearing member deflection rigidity, and the pullout softening behavior on the mobilization of pullout bearing resistance are explicitly included in the proposed model. Good agreement has been obtained between calculated values and laboratory test results.

抄録全体を表示

(,)-2,3-エポキシ-3,,11,11-テトラメチルシクロウンデカ-,-ジエン(2)をフムレン1((2,,)-3,,11,11-テトラメチルシクロウンデカ-2,,-トリエン)より合成する既知の合成法は実際に牧率が低く合成的に問題がある.さらに,2の合成はその反応性や物性の研究のために簡単に高牧率で行われることが望まれる.今回,2の新たな合成法と簡便な精製法を見いだし,2を高牧率で1から合成することができたので報告する.1のジエポキシ化,続く再結晶により得られたジエポキシド(8)は二価のチタンにより還元されて,1(273%)と8(25%)と少量の3を含む2を主生成物(42.%)として与えた.1と3は原料として再利用できる.2の精製は1と同様硝酸銀(AgNO₃)錯体の結晶で行い,純粋な2は1から通算牧率32.0%で得られた.2の既知方法による合成は4段階の反応と数回のカラム分離及び10%AgNO₃含浸シリカゲルカラム分離を必要とし牧率が極端に低い.今回,新しい2の合成法は2段階の反応で1回のカラム分離と再結晶により高い通算牧率を示す.

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 -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 ±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

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), (3), (4), 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 (3) 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