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The response analysis of reinforced concrete (RC) structures subjected to strong earthquake motions require realistic conceptual models. The special models, such as Clough and Takeda, which describe the non-linear section characteristic of reinforced concrete beam and column. In the earthquake motions, the deforming is sensitive to the response of structures intensively. The traditional lumped plastic model inevitably induces inaccuracy. Hence, meshing the members or distributing stiffness along the whole member is employed to simulate the seismic response of the structures. In this paper, Takeda elastic-plastic beam element model has been developed, which is based on general FEM code ABAQUS in order to simulate the response of RC. The influence is discussed due to the different lengths of plastic zone and element sizes.

Abstract:: We present results of scanning tunneling spectroscopy (STS) measurements of hydrogen-saturated silicon clusters islands formed on Si(111)-( 7×7) surfaces. Nanometer-size islands of Si6H12 with a height of 0.2-4 nm were assembled with a scanning tunneling microscope (STM) using a tip-to-sample voltage larger than 3 V. STS spectra of Si6H12 cluster islands show characteristic peaks originating in resonance tunneling through discrete states of the clusters. The peak positions change little with island height, while the peak width shows a tendency of narrowing for the tall islands. The peak narrowing is interpreted as increase of lifetime of electron trapped at the cluster states. The lifetime was as short as 10-13 s resulting from interaction with the dangling bonds of surface atoms, which prevents charge accumulation at the cluster islands.

AlGaAs–GaAs based quantum well nanopillar arrays are fabricated by using the UV lithography and the chlorine based reactive ion etching. The nanostructure is fabricated so as to get the confinement of carriers within the i-GaAs quantum well layer of 9 nm thick sandwiched between two barrier layers of Al0.33Ga0.67As of 11 nm thick in order to induce the possible light emission from the quantum well region. The size of pillars is obtained from SEM analysis. The number of pillars available within the 1 μm2mesa size is found to be around 400 having the pillar size between 10 and 50 nm. Electroluminesence (EL) is detected from the nanopillars when applying a forward bias voltage of ≥1.3 V and the emitted light is observed at around 830 nm.

Background/aims The biochemical basis for the development of subepithelial opacity of the cornea after excimer laser keratectomy has yet to be fully defined. The aim of this study was to evaluate the alterations of glycosaminoglycans (GAGs) after excimer laser keratectomy. Methods Rabbit corneas were harvested on days 5, 10, 20, and 30 after excimer laser photoablation. The amount of main disaccharide units was determined by high performance liquid chromatography (HPLC). In addition, immunohistochemical studies were performed on corneal sections 20 days after the ablation. Results The concentrations of ΔDi-0S at 5 and 10 days were significantly lower than before the ablation. ΔDi-6S showed a significant increase 5 days after the ablation but ΔDi-4S did not show any significant change. There was a significant increase in ΔDi-HA at 20 and 30 days after ablation. In immunohistochemistry, the positive staining for ΔDi-6S and hyaluronic acid was observed in the subepithelial region. These immunohistochemical results were well correlated with the HPLC findings. Conclusions The increase in chondroitin-6 sulphate and hyaluronic acid may be related to corneal subepithelial opacity after excimer laser keratectomy.

The effects of a novel compound, 1-(3-chloroanilino)-4-phenylphthalazine (MY-5445), on cyclic nucleotide metabolism and in vitro aggregation of human platelets were investigated. The concentrations of MY-5445 producing 50% inhibition of human platelet aggregation induced by 3 microM ADP, 3 micrograms/ml of collagen and 100 micrograms/ml of arachidonic acid were 0.07, 0.02 and 0.17 microM, respectively. Addition of MY-5445 significantly elevated cyclic GMP content in human platelets but had no effect on cyclic AMP content, suggesting that the drug affects principally the cyclic GMP metabolism in the platelet. Although MY-5445 had no effect on either adenylate cyclase or guanylate cyclase activity, it inhibited specifically human platelet cyclic GMP phosphodiesterase which was separated from cyclic AMP phosphodiesterase by diethylaminoethyl-cellulose column chromatography. The inhibitory effect of MY-5445 on cyclic GMP phosphodiesterase was also demonstrated by direct binding of the enzyme to MY-5445 coupled Sepharose, which was a useful tool for purifying the cyclic GMP phosphodiesterase from human platelet. These results would suggest that MY-5445 inhibits human platelet aggregation by increasing cyclic GMP content and that it provides a useful probe for elucidating the role of cyclic GMP in platelet aggregation.

A chemically stable prostacyclin analog, KP-10614 [(4z,16s)-4,5,18,18,19,19-hexadehydro-16,20-dimethyl-delta 6(9;alpha)-9(o)- methano-PGI1], has been compared with two other prostacyclin derivatives (Iloprost and TEI-7165) and one prostaglandin E1 derivative (OP-1206) with respect to ADP-induced in vitro aggregation of human platelets and ex vivo platelet aggregation in rats and dogs, given by bolus injection and i.v. infusion. These compounds were also tested on the systemic arterial blood pressure of rats and dogs. KP-10614 was the most potent inhibitor of in vitro platelet aggregation induced by ADP with IC50 of 1 nM among the compounds studied in this report, and it also showed ex vivo effectiveness at doses much lower than the other three compounds. KP-10614 was also orally active. At oral doses of 25, 50 and 100 micrograms/kg, this new compound caused a dose-dependent inhibition of ex vivo platelet aggregation in rats, whereas the other three compounds were effective only at 500 micrograms/kg or more. In addition, KP-10614 showed definite antithrombotic effects at a dose range of 0.1 to 1 microgram/kg i.v. in various thrombosis models in which platelet aggregation was mainly involved. These results indicate that KP-10614 possesses therapeutic potential in thrombotic diseases.

We have studied the effects of midazolam and flunitrazepam on extracellular concentrations of dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in rat striatum in freely moving animals using in vivo microdialysis. I.v. injections of midazolam 0.075 and 0.15 mg kg-1 decreased striatal dopamine concentrations in a dose-dependent manner without affecting the concentrations of DOPAC and HVA. Flunitrazepam 0.015 and 0.03 mg kg-1 also decreased striatal dopamine concentrations in a dose-related manner, but the reductions in DOPAC and HVA were not significant. Flumazenil 6 micrograms kg-1 alone did not affect striatal concentrations of dopamine, DOPAC and HVA, but it prevented the effects of midazolam and flunitrazepam. Flunitrazepam 10 mumol litre-1 also decreased striatal dopamine release when infused through a dialysis probe placed into the striatum, but it failed to affect striatal dopamine release when infused into the ipsilateral substantia nigra. Central administrations of midazolam were effective only when the drug was infused into both sites simultaneously (10 and 100 mumol litre-1) or given by intraventricular injection (0.5 and 1 micrograms). These results suggest that midazolam and flunitrazepam affect striatal dopamine release in a different manner.

A chemically stable prostacyclin analog, KP-10614 [(4Z,16S)-4, 5, 18, 18, 19, 19-hexadehydro-16,20-dimethyl-delta 6(9 alpha)-9(O)-methano-prostaglandin I1], was synthesized to increase the cytoprotective activity and to decrease the hypotensive activity. We have reported that KP-10614, infused i.v. at a dose of 3 ng/kg/min for 4 hr, inhibited platelet functions and reduced the experimental cardiac infarct size significantly, but did not change hemodynamic parameters and the ischemic area of the heart induced by ligation of the left descending coronary artery in rats. Accordingly, we thought that myocardial protective effects of KP-10614 might be based on the inhibition of platelet functions and cellular metabolism produced by platelets at the site of tissue injury. KP-10614 suppressed leukotriene B4 synthesis by N-formyl-methionyl-leucyl-phenylalanine-stimulated polymorphonuclear leukocytes, which was enhanced by thrombin-treated platelets in a concentration-dependent manner, even though KP-10614 did not suppress leukotriene B4 synthesis by N-formyl-methionyl-leucyl-phenylalanine-stimulated polymorphonuclear leukocytes separately in vitro. Moreover in in vivo studies, KP-10614, which was infused at a dose of 3 ng/kg/min for 4 hr, suppressed leukotriene B4 content, myeroperoxidase activity and polymorphonuclear leukocyte counts in myocardial tissues that were infarcted by ligation of the left descending coronary artery for 4 hr in rats. These data supported the hypothesis that KP-10614, a new prostacyclin analog, had protective effects on myocardial infarction in rats by suppressing the platelet-polymorphonuclear leukocyte interaction at the site of tissue injury in vivo.

Spin coating has been used to produce films of various chemical derivatives of C60on the hydrogen terminated silicon (100) surface. Irradiation of these films using a 20 keV electron beam has been found to reduce substantially their dissolution rate in organic solvents such as monochlorobenzene and chloroform. Raman and FTIR spectroscopy have shown that the reduced solubility of the derivative films is due to fragmentation of the molecules. The electron dose threshold of the derivative films for fragmentation is between 10−3and 10−2C/cm2, suggesting that these derivatives could be used as electron beam resists.

A chiral phase-transfer catalyst has been applied to the asymmetric allylation of the tert-butyl glycinate-benzophenone Schiff base with various allylic acetates for the first time to give the allylated products in good yields and with comparable to higher enantioselectivity than for asymmetric alkylation at the same temperature (91−96% ee) without any chiral ligands for coordinating to the palladium.

Preliminary results were obtained from thick sections of biological specimens using 200 keV electron microscopes with an in-column “Omega” energy filter. Images of selectively stained specimens prepared by osmium impregnation of frog spinal ganglia, with thickness ranging from 0.5 μm to 2.5 μm, show drastic improvement in image quality with the use of the energy filter.Two instruments with Omega filters were used. One was a non-commercial research prototype at JEOL Ltd. equipped with a LaB6gun and the other was a commercial instrument (JEM-2010FEF) with a field-emission gun, installed at Kyushu University. We found that, although the field-emission gun offered a brightness 2 to 3 orders of magnitude higher, the LaB6 gun was more suitable for studying thick specimens, primarily due to the higher beam current of the LaB6gun.

Preliminary results were obtained from thick sections of biological specimens using 200 keV electron microscopes with an in-column “Omega” energy filter. Images of selectively stained specimens prepared by osmium impregnation of frog spinal ganglia, with thickness ranging from 0.5 μm to 2.5 μm, show drastic improvement in image quality with the use of the energy filter.Two instruments with Omega filters were used. One was a non-commercial research prototype at JEOL Ltd. equipped with a LaB6gun and the other was a commercial instrument (JEM-2010FEF) with a field-emission gun, installed at Kyushu University. We found that, although the field-emission gun offered a brightness 2 to 3 orders of magnitude higher, the LaB6 gun was more suitable for studying thick specimens, primarily due to the higher beam current of the LaB6gun.

The new compounds hieracin I (I) and hieracin II (II) are isolated from the title species together with the known guaianolides jacquilenin (IIIa) and 8‐deoxylactucin (IIIb).

Neuromuscular effects of lignocaine during and after i.a. infusion were studied in healthy adult patients, using evoked electromyography. Supramaximal, paired stimuli were applied to the ulnar nerve with variable intervals between the two stimuli. The amplitude of the hypothenar muscle action potential to the second component of the paired stimulus (test response) was compared with that evoked by the first component (conditioning response). During and after i.a. infusion of lignocaine, there were marked decreases of the test response at intervals from 7 to 100 ms after the conditioning stimulus, although the decreases of the conditioning response were slight or negligible. The finding of decreased test responses coincided with the results obtained with tetanic stimulation such as pronounced fade and only slight post-tetanic potentiation. Differences between these findings and those found with muscle relaxants were compared, and it was concluded that the mechanism responsible for these results might be attributed to an effect of lignocaine on the motor nerve terminal.

Supramaximal paired stimuli were applied to the ulnar nerve, and the amplitude of the muscle action potential evoked in the abductor digiti minimi by the second member of the stimulus pair (test response) was compared with that evoked by the first component (conditioning response). The interval between the two components of the stimulus pair (the pair interval) was increased stepwise from 7 to 100 msec and a curve (recovery curve) was obtained by relating the changes in pair interval to the difference in amplitude of the test and conditioning responses. Alterations of the recovery curve (RC) during partial paralysis by muscle relaxants were investigated in healthy adult patients under the lightest plane of general anaesthesia. The control curve obtained in 32 subjects before the administration of a muscle relaxant drug was characterized by slight depressions at very short intervals of paired stimuli, followed by a slight potentiation at 20–100 msec. With non-depolarizing relaxants, RC altered to the characteristic pattern of potentiation at very short intervals of stimuli, followed by a notable depression at longer intervals. In depolarizing blocks with small doses of suxamethonium, the depression of RC at short intervals in the control was enhanced and the pattern of RC was different from that of non-depolarizing agents. When desensitization blocks were instigated by the i.v. administration of suxamethonium, the RC patterns were similar to those of competitive agents.