Protein binding effects of salivary excretion of phenobarbital in dogs

The salivary excretion of phenobarbital was investigated by collecting parotid saliva (Pr) and mandibular-sublingual saliva (MS) separately after intravenous administration in beagle dogs. (1) The alterations in the proportions of saliva secreted by the different glands were produced by salivation stimulants such as citric acid, ascorbic acid, sodium chloride and sodium glutamate. (2) The phenobarbital concentrations in both Pr amd MS were lower than those in plasma. The drug concentrations in MS were significantly lower than in Pr with stimulus of 10% citric acid of 15% sodium chloride (p less than 0.05). There was a significant correlation between phenobarbital concentration in each saliva and plasma specimen ( p less than 0.05). (3) The stimulation with 10% citric acid produced higher saliva /plasma drug concentration ratios (S/P ratios: 0.923 +/- 0.175 for Pr, 0.633 +/- 0.073 for MS) than that with 15% sodium chloride (S/P ratios: 0.597 +/- 0.071 for Pr, 0.509 +/- 0.067 or MS). (4) The S/P ratios were hardly influenced by salivary flow rates, at least under the experimental conditions examined in this study. (5) The increased S/P ratios were observed with higher salivary pH and then the equation of Matin et al. 3) seemed to hold for the average values of salivary pH and S/P ratio. (6) The stimulation with 10% citric acid produced higher protein concentration in saliva and higher S/P ratio than that with 15% sodium chloride following alternate stimulations in the same dog.     

Gain scheduling control of variable speed WTG under widely varying turbulence loading

Probabilistic paradigms for wind turbine controller design have been gaining attention. Motivation derives from the need to replace outdated empirical-based designs with more physically relevant models. This paper proposes an adaptive controller in the form of a linear quadratic Gaussian (LQG) for control of a stall-regulated, variable speed wind turbine generator (WTG). In the control scheme, the strategy is twofold: maximization of energy captured from the wind and minimization of the damage caused by mechanical fatigue due to variation of torque peaks generated by wind gusts. Estimated aerodynamic torque and rotational speed are used to determine the most favorable control strategy to stabilize the plant at all operating points (OPs). The performance of the proposed controller is compared with the classical proportional-integral-derivative (PID) controller. The LQG is seen to be significantly more efficient especially in the alleviation of high aerodynamic torque variations and hence mechanical stresses on the plant drive train. Simulation results validate the effectiveness of the proposed method.     

Effects of the GABA mimetic drug, sodium valproate, on event-related potentials and its relation to the law of initial value

The effects of gamma-aminobutyric acid (GABA) mimetic drug sodium valproate (VPA) on event-related potentials (ERPs) were investigated in 18 healthy volunteers during an auditory odd ball task. VPA (200 or 400 mg) or an inactive placebo was administered according to a completely randomized double-blind, cross-over design. ERPs were recorded one hour after medication was given. VPA did not affect the latencies of N100, P200, N200 and P300. Although on the whole VPA had no effect on the amplitudes of the ERP components in the subjects, it increased the P300 amplitude in the low P300 amplitude subjects and decreased it in the high P300 amplitude subjects. This tendency toward a bidirectional response was also seen in the P200 and N200 amplitudes. It was concluded that the response which takes place being dependent on the difference in the initial values was recognized on the effect of a single administration of 200 or 400 mg VPA to ERPs. The results of this study are discussed, especially in relation to the law of initial value.     

Effect of Silicate Anion Structure on Fixation of Chloride Ions by Calcium Silicate Hydrates

Calcium silicate hydrates, CaO–SiO₂-H₂O (C-S-H), were studied as a chloride fixation material. C-S-H of two different CaO/SiO₂ ratios were synthesized and burned with calcium chloride in a temperature range from 600° to 1000°C. Minerals with a chemical composition of CaO·SiO₂·CaCl₂ and 9CaO·6SiO₂·CaCl₂ were identified by X-ray diffraction analysis. Comparing the diffraction intensity, it was found that the most efficient chloride fixation was attained when burned at 800°C. Changes in the morphology of silicate anion associated with burning and fixation of the chloride were studied in terms of chloride fixation capability using the trimethylsililation technique. It was confirmed that some silicate anions formed a glassy infinite chain where the chloride ions were fixed as a solid solution.     

Electromagnetically coupled coaxial dipole array antenna

A new type of collinear antenna called electromagnetically coupled coaxial dipole array antenna is proposed. The antenna has an advantage of structural simplicity due to a novel use of an electromagnetically coupled feed structure for the radiating element. An analysis of the radiating element is presented and compared with experimental results. Fabrication and measurement of a prototype array antenna are also presented     

Reactions of carbon black. Part I. Nonthixotropic carbon black compositions

The solution polymerization of butyl acrylate in the presence of a furnace black was found to produce a stable dispersion of carbon black which showed Newtonian flow, while the mixture prepared by mixing the same carbon black into a solution of poly(butyl acrylate) homopolymer had a large degree of thixotropy. A marked change in the viscosity of the reaction mixture was also observed at an early stage of polymerization when the initial mixture which was a moist mass with no fluidity, turned to a fluid easily stirred. The change in viscosity and the transition in flow behavior were carefully followed with a rotary cylinder type viscometer. The non-Newtonian initial mixture was found to turn to a Newtonian fluid at low conversion of the monomer. Beside the adsorption of the homopolymer onto the surface of carbon black particles, which would occur also in mechanical mixing, the change in the flow behavior was estimated to be caused by the change in the shape and the size of the dispersed carbon black particles due to the change in the condition of the surface of the particles by which growing polymer radicals, as well as initiator radicals, were captured.     

Superior sagittal sinus thrombosis presenting with subarachnoid hemorrhage in a patient with aplastic anemia

A 54-year-old female, who had been treated for aplastic anemia by metenolone acetate since 1981, developed a sudden unconsciousness in September 1995. On admission, she was drowny, CT showed a subarachnoid hemorrhage (SAH) in the right Sylvian fissure. Angiography demonstrated a complete occlusion of the superior sagittal sinus. The SAH was assumed to be originated from rupture of the right Sylvian vein, which was irregularly dilated on angiography. The dural sinus thrombosis was thought to be caused by a long term use of metenolone acetate, and it was discontinued. But her platelet count dropped due to the aggravation of aplastic anemia, and she developed repeated hemorrhagic infarction. An active anticoagulant therapy for the dural sinus thrombosis was thought to be inappropriate because she had the aplastic anemia and the hemorrhagic infarction recurred. We have successfully treated this case by mild anticoagulant therapy with nafamostat mesilate (Futhan).     

High efficiency control of synchronous reluctance motors using extended Kalman filter

High-efficiency control of synchronous reluctance motors (SynRMs) is very important in the sense of energy saving and conservation of the natural environment because the efficiency of the SynRM is generally lower than that of other types of AC motors. This paper presents a high-efficiency control strategy for the SynRMs. In this strategy, the d- and q-axes currents are controlled instantaneously. Since the control performance mainly depends on the accuracy of the machine parameters, online parameter estimation using the extended Kalman filter is incorporated into the control strategy. This control strategy improved the drive efficiency and robust performance against machine parameter variations. The validity of the proposed scheme is demonstrated through experimental results.     

Application of ADINA to nonlinear analysis of reinforced concrete shear walls with openings

This paper is concerned with application of ADINA to elasto-plastic analysis of the shear walls with openings. The authors analyzed the types of structures. One is the shear wall with many openings (the model of a secondary shield wall in nuclear power plant), on which scale model experiments were made. The other is the shear wall with openings in concrete rigid frame (the model of a shear wall in a building), on which parametric study was made.

In both cases, concrete is modeled using 8 nodes isoparametric 2 dimensional plane stress elements, reinforcing steels are modeled as truss elements. Concrete and elasto-plastic models are adopted for non-linear material model of concrete and reinforcing steel, respectively. The total numbers of nodes are 248–308, and that of 2D elements are 66–80.

Both analytical results are satisfactory from the view point of structural design. Close agreement to experimental results in the cracking load, crack extension, elasto-plastic stiffness and total strength was verified.