Improvement of Functional Properties of Wheat Gluten and Blood Globin by Complex-Formation with Soy Lecithin

To improve the functional properties of wheat gluten or blood globin, a lecithin-protein complex was prepared by sonicating each protein solution with soy lecithin suspension at pH 3.0. The complex formation of each protein was demonstrated by gel filtration chromatography. Both solubility and emulsifying activities of each protein in the neutral pH region were much improved by complex-formation with soy lecithin. Soy lecithin-protein complexes were stable for 4 days storage at 24°C.     

Visualizing biochemical activities in living cells through chemistry

The development of molecular probes to visualize cellular processes is an important challenge in chemical biology. One possibility to create such cellular indicators is based on the selective labeling of proteins with synthetic probes in living cells. Over the last years, our laboratory has developed different labeling approaches for monitoring protein activity and for localizing synthetic probes inside living cells. In this article, we review two of these labeling approaches, the SNAP-tag and CLIP-tag technologies, and their use for studying cellular processes.     

Preparation and characterization of glass composite using metal particles coated with semiconductive SnO2 fine particles obtained via sol—gel method

SnO₂—glass composites are promising materials for nitrogen-fireable thick film resistor systems. However, the SnO₂—glass composite has many undesirable properties which should be improved for industrial application, such as a high electrical resistivity and a large negative temperature coefficient of electrical resistance. This work was undertaken to make a survey of the methods for improvement in the electrical properties of the SnO₂—glass composites. The effect of the addition of Cu particles, with a large positive temperature coefficient of electrical resistance, on the electrical properties of SnO₂—glass composites has been investigated. Cu particles have been coated with semiconductive SnO₂ fine particles by hydrolysing tin and antimony ethoxides then firing. The coated particles have been applied as conductive components in the glass composite. Using SnO₂-coated Cu particles, Cu and SnO₂ particles are homogeneously dispersed in a glass matrix, and the electrical properties of the glass composites largely depend on the volume fraction of Cu in the glass composite. The volume fraction of Cu in the glass composite is determined by a Cu/SnO₂ volume ratio in the coated particles. From the experimental evidence, it is thought feasible to produce the glass composite having well-controlled electrical properties by the suitable selection of the Cu/SnO₂ ratio in the coated particles. This revised version was published online in July 2006 with corrections to the Cover Date.     

Miniaturization of Bubbles by Shock Waves in Gas-Liquid Two-phase Flow in the Venturi Tube

Fine bubbles have been widely applied in many fields such as industry,medical engineering and agricultures.Therefore,many attentions have been paid to the study...     

The Finite Beta Effects on the Toroidal Field Ripple in a Tokamak Plasma

The efficiency of energetic ion confinement is reduced in a tokamak plasma by the non-axisymmetric field, namely the ripple field. The ripple field is produced by a finite number of toroidal field coils. It is affected by the non-axisymmetric finite beta effect. The three-dimensional MHD equilibrium calculation code VMEC is used to analyze the non-axisymmetric finite beta effect in a ripple tokamak. In the VMEC code, the flux coordinates are used, so the calculation region is limited to the area of plasma. To calculate the orbit outside the plasma, we develop a field calculation code, which is based on the Biot-Savart law. The details of the method and results are described in this paper.     

A matrix formulation for the estimation of weighting sequence matrix

The use of psoudo-random binary sequence for the estimation of weighting sequence matrices of multivariable discrete-time systems is studied using the matrix approach and the least squares method. The input phase separation scheme is used for test signal. Another approach, which is a little less optimal but yet computationally much simpler, is also presented.     

Comparison of Damages on Tungsten Surface Exposed to Noble Gas Plasmas

Tungsten was exposed to pure Ar or Ne plasmas over 1550 K at several incident ion energies. Even under the irradiation condition that the tungsten nanostructure is formed by He plasma irradiation, holes/bubbles and fiberform nanostructures were not formed on the surface by exposure to Ar or Ne plasmas. In addition, the results from energy dispersive X-ray spectroscopy supported the facts that Ar and Ne did not remain in the sample. We will discuss the reason for the diferences in the damage to the tungsten surface exposed to noble gas plasmas.     

HYDROLYSIS OF PHYTATE IN BROWN RICE-ADDED BREAD BY ADDITION OF CRUDE AND PURIFIED ASPERGILLUS NIGER PHYTASE PREPARATIONS DURING BREAD MAKING

Brown rice-added breads were prepared with and without crude and purified Aspergillus niger phytase preparations. By adding 30% (w/w) brown rice flour and no phytase preparation, the phytate (myo-inositol hexaphosphate; IP₆) content of the bread was increased and the loaf volume was reduced. The direct addition of a food-additive grade phytase preparation (3,000 U) resulted in a significant decrease in the IP₆ content. However, it collapsed the bread crust. The crude phytase preparation had significant protease and amylase activities. A simple chromatographic method for the separation of phytase activity from the protease and amylase activities was developed. By using purified phytase, the IP₆ content was reduced without any adverse effects on the rising of the bread, which indicates that protease and amylase may be responsible for the collapse of the crust by the commercial phytase preparation.

PRACTICAL APPLICATIONS

Phytate in unrefined cereals and beans lowers bioavailability of minerals. On the other hand, these materials are rich in health-promoting components. To reduce the phytate in them during processing, some commercially available phytase preparations are now used. However, we found that such preparation contains significant amylase and protease activities, which may cause adverse effect on the appearance and textural properties of final products. To solve these problems, a simple and inexpensive procedure for separation of phyatase from amylase and protease was developed in the present study. The purified phytase can reduce phytate in brown rice-added bread without adverse effect on rising of bread. These results would encourage prepare the phytase preparation in high purity in an industrial scale to improve nutritional value of unrefined cereal- and bean-based functional foods.     

Factors Affecting Heat-Induced Gel Formation of Bovine Serum Albumin

Factors affecting heat-induced gel formation of bovine serum albumin (BSA) were studied. In the presence of NaCl (I>0.05), well-developed transparent gels formed on both sides of the isoelectric point (Ip). Addition of CaCl₂ or MgCl₂ greatly suppressed gel formation on the alkaline side of Ip, but increased it a little on the acid side. Intermolecular s-s bonds contributed to the gel formation on the alkaline side of Ip but not on the acid side. From the results of the infrared spectra measurements intermolecular β-structure appears to contribute to gel formation on both sides of the Ip.     

Artificial neural networks paddy-field classifier using spatiotemporal remote sensing data

Monitoring changes in a paddy-field area is important since rice is a staple food and paddy agriculture is a major cropping system in Asia. For monitoring changes in land surface, various applications using different satellites have been researched in the field of remote sensing. However, monitoring a paddy-field area with remote sensing is difficult owing to the temporal changes in the land surface, and the differences in the spatiotemporal characteristics in countries and regions. In this article, we used an artificial neural network to classify paddy-field areas using moderate resolution sensor data that includes spatiotemporal information. Our aim is to automatically generate a paddy-field classifier in order to create localized classifiers for each country and region.