COMPARATIVE STUDY OF ENZYMATIC CHARACTERISTICS OF TRYPSINS FROM THE PYLORIC CECA OF YELLOW TAIL (SERIOLA QUINQUERADIATA) AND BROWN HAKELING (PHYSICULUS JAPONICUS)

Trypsins from the pyloric ceca of two fish species, yellow tail (Seriola quinqueradiata) and brown hakeling (Physiculus japonicus) were purified by a series of chromatographic separations. Purity increased 62‐ and 106‐fold with approximately 55 and 10% yield for yellow tail trypsin and brown hakeling trypsin, respectively. Final enzyme preparations were homogeneous in sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE), and the molecular weights of both enzymes were estimated to be 24 kDa by SDS‐PAGE. Yellow tail and brown hakeling trypsins had maximal activity at pH 8.0 for hydrolysis of N_α‐p‐tosyl‐L‐arginine methyl ester hydrochloride and was unstable at acidic pH. The optimum temperatures for yellow tail and brown hakeling trypsins were 60 and 50C, respectively. Yellow tail trypsin was stable up to 50C, whereas brown hakeling was stable up to 40C. Both trypsins were stabilized by calcium ions. The activities of both trypsins were strongly inhibited by soybean trypsin inhibitor and N_α‐p‐tosyl‐L‐lysine chloromethyl ketone hydrochloride, and were partially inhibited by ethylenediaminetetraacetic acid. The N‐terminal amino acid sequences of yellow tail trypsin and brown hakeling trypsin were determined as IVGGYECTPYSQPHQVSLNS and IVGGYECPKHSQPHQVSLNS, respectively.     

PURIFICATION AND PROPERTIES OF DESMUTAGENIC FACTOR FROM BROCCOLI (BRASSICA OLERANCEA VAR. ITALICA PLENCK) FOR MUTAGENIC PRINCIPLE OF TRYPTOPHAN PYROLYSATE

A desmutagenic factor which inhibited the mutagenicity of the mutagens, Trp-P-1 (3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole), Trp-P-2 (3-amino-1-methyl)-5H-pyrido[4,3-b]indole), ethidiumbromide and 2-aminoanthracene, was purified from broccoli (Brassica olerancea var. italica plenck). The factor was not sedimented by ultra-centrifugation at 200,000 xg for 2 h. It adsorbed to a DEAE-cellulose column and was eluted with low concentration of potassium chloride. The purified factor exhibited a heme-like protein absorption spectrum with a Soret band at 403 nm and α and β bands at 640 and 504 nm, respectively. The molecualr weight was estimated to be approximately 53,000 by SDS-gel electrophoresis.     

Spectral Variation of SKβ Emission with Sulfur Content in As-S Glasses

The bonding and chemical state of sulfur in binary As-S glasses were investigated by determining the S Kβ spectra with a vacuum 2-crystal X-ray spectrometer equipped with Ge(ll1) crystal analyzers. For glasses with sulfur contents <60 at.%, the spectra were similar to those of realgar (crystalline As₄S₄) and orpiment (crystalline As₂S₃); the profile of the SKβ spectrum did not change when half the sulfur was replaced by selenium. For sulfur contents > 60 at.%, the spectra became progressively similar to that of elemental sulfur with increasing sulfur content. It was found that S-S bonding occurs in the high-sulfur glasses.     

上海八号桥时尚创作中心

上海建国中路八号桥项目是一个工厂改建的实案。文章扼要介绍将工厂进行空间更新与功能更新的主要构思。     

PREDICTIVE BANG-BANG CONTROL FOR MANAGEMENT OF GROUND TEMPERATURE BASED ON FINITE ELEMENT METHOD

Recently, applications of the control of ground temperature have been widely used for the maintenance of lawns and underground storage tanks, road surface temperature control, etc. This paper presents a predictive bang-bang control to perform a real-time and practical control method. A time series of the future exterior boundary condition, used for the predictive control, is predicted by the Kalman filter technique. The basic equation of the ground temperature is discretized by the finite element method in space and the Crank–Nicolson method in time. To obtain the predictive control temperature, the performance function is minimized at every time step by the Sakawa–Shindo method. © 1997 John Wiley & Sons, Ltd.     

Highly Sensitive Method for Urea Detection in Wine

Trace amounts of urea (less than 50 μg/L) in wine were accurately determined using a modified high performance liquid chromatography (HPLC-fluorometric) technique. Appropriate selection of eluent, HPLC columns, and chiral derivatives for the o-phthalaldehyde solution provided a 20-fold enhancement of sensitivity over established methods. A linear relationship was observed at concentrations from 0.5–500 μg/L of aqueous urea solution. The threshold level for detectability of urea in wine was 5 μg/L. The method is simple enough to be applicable to most beverages.     

Analysis of pigmentation in human skin: quantification of ultraviolet ray images by digital image processing

A new method for quantifying pigmentation with transformation of ultraviolet ray images into digital images has been developed. Utilizing this method, the distribution of pigments deposited in healthy Japanese subjects has been investigated. The following characteristics of pigmentations have now been obtained as follows:
— the amount of total pigmentation areas and the frequency of appearance of large pigmented areas increase with ageing;
— in young and middle age groups, women have more pigmentation than men, whereas in old age, this trend is reversed;
— the amount of pigmentation is greatest on the front of the cheeks and the least on the forehead;
— pigmentation areas darken in summer, and the amount of pigmentation and number of pigmented areas increase in summer.
Interestingly enough, a correlation between 'ultraviolet rays in daily life' and 'the pigmentation in human skin' is strongly suggested.     

Conversion of Provitamin D3 to Vitamin D3 by Monochromatic Ultraviolet Rays in Fish Dark Muscle Mince

To determine whether the photochemical conversion of provitamin D₃ is possible in fish meat, the dark muscle of skipjack was irradiated with monochromatic ultraviolet rays (peak, 305 nm; range, 280–360 nm) under various conditions of both time of exposure and strength of light. The vitamin D₃ and provitamin D₃ content were analyzed by HPLC. The vitamin D₃ content increased, and the provitamin D₃ content decreased with 20W light at a distance of 50 cm. The conversion was at a maximum 15 hr after the start of irradiation and about 20% of the provitamin D₃ changed to vitamin D₃