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- 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.Vp-p input signal at each input terminal in the pseudodifferential configuration. The LPF including an output buffer dissipated 60mW in the case of a .2V supply. Wide spurious-free dynamic range (SFDR) characteristics were confirmed up to high frequencies.

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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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Failure problems of saturated soils are classified in the present study into the following four types : Type I : The failure of loose and/or normally consolidated soils under fully drained loading conditions. Type II : The same soils but under perfectly undrained conditions. Type III : The failure of dense and/or overconsolidated soils under fully drained conditions. Type IV : The same soils but under perfectly undrained conditions. The soil-water coupling limiting equilibrium analysis on the basis of the critical state concept is shown possible to draw a distinction between type I, II and IV problems, and the limitations of the analysis procedure happen in solving the type problem in the above. This is demonstrated experimentally, in which seepage failure experiments in laboratory with the use of a saturated silty sand are employed to make distinctions clearly between the four types of failure problems. The definite distinctions both in failure load and failure mode appeared in the four types of experiments are summarized as follows : () the smallest failure load in loose sand in the undrained condition, (2) the largest failure load with the largest failure region in dense sand under undrained loading, () the observation of no global deformation before failure within the soil under the fully drained condition that suggests the development of very localized shear deformation in the sand. Three out of four experiments are described well by the limit analysis computation mentioned above as far as the failure load and the shape and the size of the failure region after boiling failure are concerned, and thus the type III problem is identified to be the problem that should be solved by any other means in near future.

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Activity-directed isolation of the ethyl acetate, methylene chloride and n-hexane fractions of Gloiopeltis furcata resulted in the isolation of 18 compounds. Their structures were elucidated as 2-(-hydroxy--oxotetrahydrofuran--yl)acetic acid (), glutaric acid (2), succinic acid (), nicotinic acid (), ()--hydroxyhex-2-enoic acid (), cholesterol (6), -hydroxycholesterol (), uridine (), glycerol (), -(hydroxymethyl)-2-methoxybenzene-,-diol (10), (,)--oxodeca-,-dienoic acid (11), (Z)--ethylidene--methylpyrrolidine-2,-dione (12), dehydrovomifoliol (13), loliolide (14), cholesteryl stearate (15), palmitic acid (16), cis-,,11,14,17-eicosapentaenoic acid (17) and α-linolenic acid (18) on the basis of spectroscopic and chemical evidences. Their anticholinesterase and antioxidant activities were evaluated via inhibitory activities on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) as well as scavenging activities on ,-diphenyl-2-picrylhydrazyl (DPPH) radical and peroxynitrite (ONOO⁻). All isolated compounds (—18) exhibited moderate AChE inhibitory activities with IC₅₀ values ranging from .14—12.50 μg/ml, whereas , , , 17, and 18 showed mild BChE inhibitory activities with IC₅₀ values ranging from .57—15.89 μg/ml. Although most of the compounds isolated were lacking the scavenging activity on DPPH radical and ONOO⁻, and 10 showed good DPPH radical scavenging activity, and , 10, and 16 showed potent ONOO⁻ scavenging activity.

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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 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 (), (2), (), (), and (), were isolated together with 11 known saponins from the saponin fraction. The chemical structures of — were elucidated on the basis of chemical and physicochemical evidence. Among the isolated saponins, theasaponins (6), (), and () and assamsaponin (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; ) the 21- and/or -acyl groups are essential for the activity, 2) acetylation of the 16-hydroxyl group reduce the activity.

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One method currently being considered for the disposal of high level radio-active waste is burial in the seabed. When a hot object is buried in soil, the temperature of the soil adjacent to the object is raised and there is transient heat flow away from the object. The rise in the temperature of the soil causes excess pore pressures to be generated and transient pore water diffusion also takes place. A finite element formulation of the coupled heat flow and consolidation problem is presented. The computer implementation of this formulation is found to compare favourably with analytical solutions based on the same physical principles.

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

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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= 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 : () 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.

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