Contents of phthalate in polyvinyl chloride toys

The presence of plasticizers in PVC toys obtained in October 1998 was investigated. Diisononyl phthalate (DINP), di-2-ethylhexyl phthalate (DEHP), di-n-butyl phthalate (DBP), dinonyl phthalate (DNP), diheptyl phthalate (DHP), and di-2-ethylhexyl adipate (DEHA) were detected. The phthalates were found in all of the 68 samples. The principal phthalate found in toys was DINP, which was present in 48 of 68 samples. The DINP content ranged from 15 mg/g to 580 mg/g, and mean content was 308 mg/g. The highest content was found in a pacifier toy. DEHP was present in 20 of 68 samples and the content ranged from 2.0 mg/g to 380 mg/g. The mean content was 162 mg/g. It was found in 60% of domestic toys.     

Efficient expression, purification and characterization of mouse salivary alpha-amylase secreted from methylotrophic yeast, Pichia pastoris

We constructed a secretion vector of mouse salivary alpha-amylase, pPAM, using the AOX1 promoter-terminator and the secretion signal of 128 kDa pGKL killer protein, for an alternative yeast, Pichia pastoris. Taking advantage of multicopy insertion of the expression cassette and optimized growth conditions, we succeeded in highly efficient extracellular production (approximately 240 microg/ml) of mouse alpha-amylase in the 10 ml scale by conventional flask culture: this efficiency was about 90-fold higher than that of Saccharomyces cerevisiae. Growth temperature of cells was critical for efficient production of alpha-amylase. P. pastoris transformants secreted both core-glycosylated and non-glycosylated alpha-amylase molecules with a glycosylated:non-glycosylated ratio of about 20:80. Both glycosylated and non-glycosylated alpha-amylases were purified separately to apparent homogeneity. The signal sequence was correctly processed in both species, and the molecular masses of glycosylated and non-glycosylated alpha-amylase were determined to be 58 600 and 56 300, respectively, by mass spectrometry. We further studied the outer chain glycosylation of engineered mouse alpha-amylase secreted by P. pastoris.     

Efficient Identification of the MYC Regulator with the Use of the CRISPR Library and Context-Matched Database Screenings

MYC is a major oncogene that plays an important role in cell proliferation in human cancers. Therefore, the mechanism behind MYC regulation is a viable therapeutic target for the treatment of cancer. Comprehensive and efficient screening of MYC regulators is needed, and we had previously established a promoter screening system using fluorescent proteins and the CRISPR library. For the efficient identification of candidate genes, a database was used, for which mRNA expression was correlated with MYC using datasets featuring “Similar” and “Not exactly similar” contexts. INTS14 and ERI2 were identified using datasets featuring the “Similar” context group, and INTS14 and ERI2 were capable of enhancing MYC promoter activity. In further database analysis of human cancers, a higher expression of MYC mRNA was observed in the INTS14 mRNA high-expressing prostate and liver cancers. The knockdown of INTS14 in prostate cell lines resulted in decreased MYC mRNA and protein expression and also induced G0/1 arrest. This study confirmed that CRISPR screening combined with context-matched database screening is effective in identifying genes that regulate the MYC promoter. This method can be applied to other genes and is expected to be useful in identifying the regulators of other proto-oncogenes.     

Effects of type of lubricant and shape of tooth profile upon efficiency of gear drives

To reduce energy consumption, it is important to increase the efficiency of gears used for power transmission. In the present work, the efficiencies of gear drives with standard and profile shifted involute gears are measured by changing the type of lubricating oil. A new equation for calculating efficiency is derived by taking into account the additional friction torque that depends on the shape of the teeth. The efficiencies calculated with the new equation agree well with those obtained by experiments conducted using two planetary gear drives with different tooth shapes and with different reduction ratios (u = 4. 89 and 151). The new equation is applicable to the design of gear drives with higher efficiency.     

Incorporating reserve supplying demand response in customer's decision making model for simultaneous energy and reserve markets

In this letter, the customer profit‐maximization‐model is expanded to incorporate the probabilistic profit of reserve supply. This extended model will change the customer behavior and therefore will affect the system performance. The analysis of the extended model is carried out to show how this model, considering energy and reserve market parameters, affects the customer decision. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.