Inclusion Compound Formation of Amylose by Sealed-Heating with Salicylic Acid Analogues

The inclusion compounds of linear amylose and salicylic acid analogues preparedby sealed-heating were evaluated by using powder X-ray diffraction and infraredspectroscopy. Sealed-heating of amylose and either salicylamide or benzoic acidinduced the amylose structural change from the 6₁- to the 7₁-helix structure, while sealed-heating with o-toluic acid, o-chlorobenzoic acid and o-nitrobenzoic acid induced the change from the 6₁- to the 8₁-helix structure. In contrast to theresults in the salicylic acid system, the amylose helix type of sealed-heated samplewas not varied by the load of the guest compound, but was fixed only by the guestspecies. No change of the helical structure of amylose depending on the amylose molecular weight was observed. From the comparison of inclusion compound formation among different guest systems, it was found that the higher vapor pressure at 100 °C of the guest resulted in faster inclusion compound formation. The vapor pressure of the guest compound would be an important factor affecting the progress of inclusion compound formation.     

Electrostrictive effects in non-polar perovskites

Polarization-related electrostrictive coefficients Q_h have been determined for relaxation dielectrics 0.856Sr TiO₃-0.144 Bi_2/3 TiO₃ and (K_3/4Bi_1/4) (Zn_1/6Nb_5/6)O₃, and for a simple non-polar perovskite BaZrO₃ by measuring the hydrostatic pressure dependence of the dielectric permittivity. Anomalous variation in the electrostrictive coefficient with temperature and frequency were observed in (K_3/4Bi_1/4) (Zn_1/6Nb_5/6)O₃ in the relaxation-temperature region. This behavior can be explained qualitatively with a simple model based on potential barriers separating alternative cation sites. The empirical rule noted previously for ferroelectric perovskites, that the electrostrictive Q coefficient increases with cation order from disordered, through simple and then ordered perovskites is confirmed again in non-polar perovskites.     

Determination of nitrocatecholamines in rat brain using high-performance liquid chromatography-peroxyoxalate chemiluminescence reaction detection

We have developed a method to determine nitrocatecholamines (nitroCAs: nitronorepinephrine (nitroNE), nitroepinephrine (nitroE), and nitrodopamine (nitroDA)) in rat brain using high-performance liquid chromatography-peroxyoxalate chemiluminescence (POCL) reaction detection. This method consists of in-line extraction of amines, including nitroCAs, followed by separation on an ODS column, reduction of nitroCAs with a reducer column, derivatization with ethylenediamine, and finally the POCL reaction detection. Use of the reducer column increased the sensitivity of detection of nitroCAs by 45-172%. The limits of detection (signal-to-noise ratio of 3) were 75fmol for nitroNE, 125fmol for nitroE, and 150fmol for nitroDA. By using this method, not only nitroNE, but nitroE and nitroDA were determined in rat brain. The concentrations of nitroNE and nitroE in rat brain were 9.2+/-2.0 and 13.5+/-2.5 pmol/g tissue, respectively (n=5).     

The growth inhibition of Streptococcus mutans by 5'-nucleotidase inhibitors from Areca catechu L

New 5'-nucleotidase inhibitors named NF-86I, NF-86II were recently isolated from the seeds of Areca catechu L. NF-86I and NF86II showed inhibitory effects on the growth of Streptococcus mutans MT8148(c) and Streptococcus mutans MT6715(g), respectively. In addition, these inhibitors could inhibit insoluble glucan formation from sucrose. NF-86I and NF-86II were found to be polyphenolic substances. Some polyphenols such as tannic acid bind non-specifically to proteins (tannic activity). The 5'-nucleotidase inhibitors that we isolated did not show any such activity. However, the growth inhibitory activity and the inhibitory effect on water-insoluble glucan production were equal to tannic acid. It is therefore considered that these inhibitors bind specifically to the bacterial cell surface. Our findings suggest that the 5'-nucleotidase inhibitors NF-86I and NF-86II may be useful anti-plaque preventing agents.     

SUNBURN CELL: FACTORS INVOLVED IN ITS FORMATION.

Abstract— The sunburn cell (SC) is a type of individual cell death appearing in epidermis principally after exposure to middle-wavelength UV radiation (UVR). Because SC_s can easily be recognized by histologic characteristics, they may provide a countable index of assessment of the degree of UVR injuries. However, despite extensive investigations, the mode of formation of this UVR-induced apoptosis has not fully been understood. In this review article, we are summarizing the results of recent studies with special reference to both the formation mechanisms and their implications in the field of photobiology.     

Photochemical synthesis of heteroatom-containing polycyclic aromatic compounds

Anthra[2,1-b]furan, anthra[2,1-b]benzo[d]furan, anthra[2,1-b]thiophene, anthra[1,2-b]thiophene, anthra[2,1-b]benzo[d]thiophene, anthra[2,1-b]pyrrole and naphtho[2,3-c]carbazole derivatives were synthesized in fairly good yields by a one-pot photocycloaddition reaction of 2,3-disubstituted 1,4-naphthoquinone with 1,1-diarylethylene. This is the first reported synthesis of these aromatic compounds.     

Film analysis employing subtarget effect using 355 nm Nd-YAG laser-induced plasma at low pressure

The applicability of spectrochemical analysis for liquid and powder samples of minute amount in the form of thin film was investigated using ultraviolet Nd-YAG laser (355 nm) and low-pressure ambient air. A variety of organic samples such as commercial black ink usually used for stamp pad, ginseng extract, human blood, liquid milk and ginseng powder was prepared as film deposited on the surface of an appropriate hard substrate such as copper plate or glass slide. It was demonstrated that in all cases studied, good quality spectra were obtained with very low background and free from undesirable contamination by the substrate elements, featuring ppm or even sub-ppm sensitivity and worthy of application for quantitative analysis of organic samples. The proper preparation of the films was found to be crucial in achieving the high quality spectra. It was further shown that much inferior results were obtained when the atmospheric-pressure (101 kPa) operating condition of laser-induced breakdown spectroscopy or the fundamental wavelength of the Nd-YAG laser was employed due to the excessive or improper laser ablation process.     

Image enhancement with lightness correction and image sharpening based on characteristics of vision for elderly persons

Optical Review - In general, as people age the functions of their sensory organs deteriorate. For example, in the eye of an elderly person, the visual field becomes dark owing to a decrease in the...     

Derivation of the analytical solution of Color2Gray algorithm and its application to fast color removal based on color quantization

In order to convert a color image into a monochrome one, the lightness components of pixels have to date been used as gray-levels for the representation of the monochrome image. However, saliencies of an image embedded only in the chrominance components are eliminated in such conversion. To cope with this problem, “Color2Gray” algorithm, which excels in the color removal of digital images, has been proposed by Gooch et al. [ACM Trans. Graphics 24 (2005) 634]. In this paper, the algorithm is first analyzed and its mathematical property is revealed. Then a fast Color2Gray algorithm is proposed by using the mathematical property. Finally, the validity and the effectiveness of the proposed algorithm are proven by some experiments.     

An autosampler with a short transfer line for Curie point pyrolysis capillary gas chromatography

A new multichannel autosampler which can automatically analyze up to twenty samples in sequence has been developed for Curie point pyrolysis – capillary GC. Compared with a previous system [1] the transfer line between the pyroysis unit and chromatograph is shorter, and thus has less dead volume, and can be operated at a higher temperature (300 °C). The relative yields of higher boiling point, highly polar, and thermally labile pyrolysates generated from polymers, and the reproducibility, were better than those obtained from the previous autosampler. To facilitate rapid operation an additional flow controller is installed on the new device to shorten the time taken to purge air from the sampler.