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.     

Mode behaviour in a tapered multimode fibre

A derivation based on ray tracing and the local plane-wave approximation is used to show the behaviour of waveguide modes in a linearly tapered multimode fibre having a step-index profile. The azimuthal mode order l is invariant through the taper, and, for suitably designed tapers, the changes in the radial mode order m and the lateral component u are negligible. A formula for designing such tapers is presented.     

Measurement of nonlinear distortion in photodiodes

The 2nd-order nonlinear distortion of avalanche photodiodes (TIXL-55, C-20817) was found to be less than ?60 dB for an incident average optical power of ?20 dBm modulated at a peak depth of 75%. p-i-n photodiodes (HP 5082-4207) were found to have 2nd-order-distortion levels below the noise level. A method using three independent optical signal sources was employed in the measurement.     

An Interactive Data Language software package to calculate ionospheric conductivity by using numerical models

The Inter-university Upper atmosphere Global Observation NETwork (IUGONET) project focuses on handling ground-based observational data of the upper atmosphere. To this end, the project members have been developing a data analysis software package which is based on Interactive Data Language (IDL). Filling the spatial gaps in observational data requires the use of numerical models. In this paper, we discuss an IDL software package for global ionospheric conductivity by integration of 3rd party numerical models. The model can be used to create further derived models.     

Photo‐response orientation behaviors of polyethylene imine backbone structures with azobenzene side chains

Polyethylene imines (PEIs) with azobenzene side groups, PEI6M and IP‐DAz, were synthesized and the effects of the substitution degree of the PEI backbone structures on the photoresponse properties and the orientation behaviors were investigated. The phase transition temperatures are closely related to thermal stability in orientational order. IP‐DAz showed only the smectic phase in a much broader range between 53 °C and 170 °C and the thermal stability was significantly improved compared with PEI6M. Reversible changes in absorption spectra relating to photoisomerization behavior for both polymers were observed by UV and visible light irradiation. Uniaxial orientation for the selective direction was induced by irradiation by linearly polarized light and the anisotropic properties were investigated by measurements of the order parameter and birefringence. Rapid photoresponses for molecular orientations were demonstrated for both polymers. Although the order parameter of IP‐DAz was lower than that of PEI6M, the birefringence of IP‐DAz for in‐plane orientation was as high as for PEI6M and is related to the stable orientational order. © 2013 Society of Chemical Industry     

Microstructure of high battery-performance Li2FeSiO4/C composite powder synthesized by combining different carbon sources in spray-freezing/freeze-drying process

Spray-freezing/freeze-drying technique was applied to the synthesis of Li₂FeSiO₄/C composite powders using solutions containing various carbon sources, water-soluble and colloidal carbon, followed by heat treatment. The effects of the carbon sources on the microstructure and battery performance of the synthesized composite powders were investigated. The microstructures of the composite powders were clearly different when different carbon sources were used, ascribed from the thermal behavior of the carbon sources during the heat treatment. It was possible to control the microstructures of Li₂FeSiO₄/C composite powders by combining different carbon sources, and the synthesized composite powders exhibited high discharge capacities by mixing with only a binder for cathode. The composite powders using glucose and Ketjenblack dispersion as carbon sources delivered 165 mAh/g at first discharge capacity at 0.1?C. The developed chain structure suitable for conducting paths in the electrodes and a higher-specific BET surface area, attributed from Ketjenblack, were likely responsible for the higher performance.     

Evaluation of an analytical method for cyanogenic compounds in beans and surveillance of cyanogenic compounds in beans

The performance characteristics of an analytical method for cyanogenic compounds were evaluated. Specifically, we tested the trueness, repeatability and intermediate precision of the method using a spectrophotometric-based detection system for 4-pyridinecarboxylic acid and pyrazolone after steam distillation. The pH adjustment of the distillate was revealed to affect the trueness of the measurements. A pH of approximately 6 was found to be optimal. The targeted quantitation limit of the cyanide ion was set to 5 mg/kg. The performance of the method was evaluated using beans spiked with cyanide ion at one to two times the quantitation limit (5-10 mg/kg). The trueness of the method was between 78-90%, and the repeatability and intermediate precision were between RSD 1.2% to 6.0%. A surveillance of cyanogenic compounds in beans retailed in Japan was then carried out. All the results were below the quantitation limit of 5 mg/kg.     

Cleanup of food samples with pre-packed multi-layer silica gel column for the analysis of PCDDs,PCDFs and dioxin-like PCBs

The cleanup procedure for the determination of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (PCBs) in food samples using a disposable pre-packed multi-layer silica gel column (multi-layer dioxin tube; D-tube) was evaluated. The blank test showed the need for conditioning of the column with n-hexane. To compare the method with the D-tube and the conventional method for the analyses of actual food samples, seven food samples (spinach, komatsuna, rice, salmon, beef, egg and butter) were extracted by shaking with acetone-n-hexane or n-hexane after alkaline treatment, and then the extracts were cleaned up by use of the D-tube or the prepared conventional column, followed by several column chromatographic steps. Both cleanup procedures gave similar values at each isomeric concentration level and showed similar efficiency with favorable recoveries. The results suggest that the D-tube is applicable to cleanup for the analysis of PCDD/Fs and dioxin-like PCBs in foods.     

Microstructural, crystal structure and electrical characteristics of shock-consolidated Ga2O3 doped ZnO bulk

Ga₂O₃ (5 wt.%) doped zinc oxide (ZnO, 95 wt.%) bulk was fabricated by underwater shock compaction technique. The microstructural, crystal structure and electrical properties of shock-consolidated samples were investigated and compared to a commercially available sintered Ga₂O₃ (5 wt.%) doped ZnO (95 wt.%). The relative density of shock-consolidated sample was about 97% of the theoretical density, and no grain growth and lattice defects were confirmed. The grain boundary resistance was remarkably higher than that of commercial sintered Ga₂O₃ doped ZnO and nonlinear current-voltage (I-V) characteristics of shock-consolidated ZnO and Ga₂O₃ doped ZnO were very lower than that of commercial ZnO varistor.