Restoration of the red colour of photo-bleached carthamine in calcium-alginate gel membranes

The restoration of the red colour of carthamine (photo-bleached in polymeric heterosaccharide gels) was investigated using sodium salts, potassium salts, and alkali. Ca-alginate gel was stained with carthamine, and the red-dish membranes were exposed to fluorescent light for 2·5, 4·0 and 20 h (at 28°C). The resulting orange-yellow gel membranes were treated with Na- or K-citrate solution and the restoration of the red colouration was followed spectrophoto-metrically. The results indicate that the red colour of carthamine can be retained within the gel membranes, while yellow-coloured compounds were removed and/or transformed by the alkaline salt solutions.     

A load dispatch method using fractional programming and semidefinite programming

This paper describes a load dispatch method which minimizes power cost—[fuel cost]/[electric output]—for a power system with thermal plants and energy storage facilities. The proposed method employs fractional programming to convert a minimization problem with fractional objective function to a series of quadratic minimization problems, and semidefinite programming to solve converted problems. The method provides the optimum time‐dependent power output/input and storage level of energy storage facilities as well as time‐dependent power output of thermal plants. The method has been applied to a power system with five thermal plants, two energy storage facilities of various performances, and five load demands. The optimum load scheme of four time mesh points is obtained for the thermal plants and energy storage facilities. The fractional programming successfully converges the optimal scheme through a few iterations. The semidefinite programming deals with a variable matrix of 164 dimensions, and 185 inequality constraints. © 2001 Scripta Technica, Electr Eng Jpn, 138(2): 49–58, 2002     

Superconductivity in W-containing diamond-like nanocomposite films

Superconductivity in a tungsten-containing carbon-oxide film was reported. The film with 500 nm thickness was deposited onto polycrystalline silicon oxides using chemical vapor deposition and the co-sputtering of a tungsten metal target. The bonding state of the carbon atoms and the macroscopic and microscopic crystal structure of the film were investigated by Raman spectroscopy, X-ray diffraction and transmission electron microscopy measurements. From the experimental results, we determined that this film essentially had an amorphous structure. The temperature dependence on resistivity was measured in the temperature range of 2–300 K. Resistive superconducting transition was observed at 3.8 K. The dc magnetizations were measured in the temperature range of 1.8–6.5 K. The diamagnetism resulting from a superconductive state was observed below 3.75 K, which is consistent with a resistive superconducting transition. It is thought that the finite sized clusters of the different superconductive transition temperatures cooperatively produce a macroscopic superconducting phenomenon.     

Effects of cononsolvency on gelation of poly(vinyl alcohol) in mixed solvents of dimethyl sulfoxide and water

We studied the rates of gelation and phase separation of poly(vinyl alcohol) (PVA) solutions in mixtures of dimethyl sulfoxide (DMSO) and water at 25 °C and found that both the rates show a maximum at a volume fraction of DMSO φ_DMSO=0.60 while gelation was not observed either in pure DMSO or pure water, suggesting that water-DMSO is a cononsolvent system for PVA. On the basis of the data by Cowie [Can J Chem 36 (1961) 2240] we concluded that the 1:2 stable complex between one DMSO molecule and two water molecules is the main cause of this cononsolvency.     

Effect of 8 MeV electron irradiation on electrical properties of CuInSe2 thin films

Radiation damages due to 8 MeV electron irradiation in electrical properties of CuInSe₂ thin films have been investigated. The n-type CuInSe₂ films in which the carrier concentration was about 3×10¹⁶ cm⁻³, were epitaxially grown on a GaAs(0 0 1) substrate by RF diode sputtering. No significant change in the electrical properties was observed under the electron fluence <3×10¹⁶ e cm⁻². As the electron fluence exceeded 10¹⁷ e cm⁻², both the carrier concentration and Hall mobility slightly decreased. The carrier removal rate was estimated to be about 0.8 cm⁻¹, which is slightly lower than that of III–V compound materials.     

Interferon therapy after ablation of Kent bundle for a patient with chronic hepatitis type B complicated with WPW syndrome

Cardiotoxicity of interferon-alpha or gamma, such as fatal arrhythmia and myocardial infarction, has been reported. Therefore cardiotoxicity of interferon should be seriously considered before administration for patients with a pre-existing heart disease. We treated a patient with chronic active hepatitis type B, coexisted with Wolff-Parkinson-White syndrome, who has had frequent attacks of paroxysmal atrial fibrillation. To prevent the occurrence of fatal arrhythmia with an interferon therapy in this patient, we performed radiofrequency catheter ablation of the Kent bundle. After the successful ablation, we could safely administered recombinant interferon alpha-2b for chronic hepatitis type B.     

Radiation tolerance of type IIa synthetic diamond detector for 14 MeV neutrons

Radiation tolerance of a type IIa synthetic diamond detector was examined from irradiation of mono-energetic 14 MeV neutrons. Measurements of I–V (current–voltage) characteristics and energy spectrum for 5.486 MeV alpha particles were performed after neutron irradiation. In the I–V characteristics measurement, enhancement of rectification was observed after neutron irradiation of up to 2.0 × 10¹² n/cm². Concurrently with the enhancement of rectification, significant decrease in signal amplitude was observed in energy spectrum measurement for alpha particles. It is considered that these changes were due to increase in the concentration of defects acting as shallow energy levels in the forbidden band. For neutron irradiation of higher than 1.6 × 10¹³ n/cm², weakening of the rectification characteristics and recovery of the signal amplitude were observed. These changes imply that deep energy levels, which were also considered to be introduced by defects, were dominant and weakened the effects of the shallow energy levels. Increase in the concentration of the deep trapping levels resulted in gradual decrease of the signal amplitude and degradation in the energy resolution. The peak for the alpha particles was obtained up to 5.5 × 10¹³ n/cm².     

Activation of the alternative pathway of human complement by apoptotic human umbilical vein endothelial cells

Complement activation generally does not occur on homologous cells. We observed C3 deposition on cultured human umbilical vein endothelial cells (HUVEC) when those which had died of apoptosis were treated with human serum. The C3 deposition on apoptotic HUVEC required Mg2+ but not Ca2+. In addition, the incubation of apoptotic HUVEC with purified C3, B, and D in the presence of Mg2+ resulted in C3 deposition. These results indicated that the C3 deposition on apoptotic HUVEC is mediated by the activation of the alternative complement pathway. C3 contains an intrachain thioester bond in the alpha chain (110 kDa) and upon activation to C3b, binds with membrane molecules by forming an ester or amide bond. Western blotting of reduced C3b-membrane molecule complexes, isolated from serum-treated apoptotic HUVEC by immunoprecipitation with anti-C3, revealed the covalent binding of C3b to several membrane molecules. Most of the C3b-membrane molecule complexes were cleaved by hydroxylamine, suggesting covalent binding via an ester bond. The molecular mass of the major alpha chain fragment released by hydroxylamine treatment was not 105 kDa but 68 kDa, which corresponds to the alpha 1 fragment of iC3b. These results indicate that most of the C3b on HUVEC was cleaved at its alpha' chain to yield iC3b, which consists of three disulfide-linked polypeptide chains and is a ligand of the complement receptor type 3 (CR3) of phagocytes. These results suggest that apoptotic HUVEC can activate the alternative pathway of the homologous complement and that the complement is related to the clearance of apoptotic cells by phagocytes.     

GH receptor gene mutations and growth failure

Abnormality of growth hormone (GH) receptor (GHR) and signal transduction system is a cause of primary GH insensitivity. Analysis of GHR gene have shown so far about 30 different kinds of mainly homozygous mutations in patients with Laron syndrome and heterozygous mutations in some patients with idiopathic short stature. In this paper, we review these diverse clinical and molecular characteristics of abnormal GHR gene in patients with GH insensitivity including our patient of Laron syndrome caused by novel compound heterozygous mutations and of familial short stature with high serum GHBP levels caused by a heterozygous splice site mutation of the GHR gene producing a lack of cytoplasmic domain.