Farnesyl diphosphate synthase from Geobacillus stearothermophilus (GsFPPS) is a thermophilic enzyme which belongs to the prenyltransferase family. We found that the point mutation of an amino acid located on the fifth position upstream of the first aspartate-rich motif (FARM) in GsFPPS (tyr81) affects its flexibility and activity. Enzymatic activities of wild-type GsFPPS, Y81D, Y81R, and Y81S were measured by a 14C radioactivity assay. Their flexibilities were assessed by monitoring the fluorescence intensity changes due to the presence of a collisional quencher and also by coarse-grained molecular dynamics (MD) simulations. Y81R and Y81S showed enhanced activities of up to 1.7-fold, while activity of Y81D was reduced by 1.2-fold. The differences in activity between these enzyme variants are caused by the differences in conformational flexibility, especially in terms of the dynamics of the areas near the active site.

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The photocatalytic degradation of 3-[3,4-(dichlorophenyl)-1-methoxy-1-methylurea] (Linuron) in aqueous solutions with TiO2 semiconductors was investigated under sunlight illumination. It was found that the primary photocatalytic decomposition reaction follows a pseudo-first order kinetic law. During the photocatalytic degradation, the first-order rate constant k was 0.12 min-1. The present degradation method will be able to be applied to various chemicals.

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Several microorganisms reportedly accumulate cesium. Among these microorganisms, Rhodococcus erythropolis CS98 shows the highest accumulation. We previously showed that agarose gel was more suitable for immobilization of the CS98 strain than calcium alginate gel and poly(vinyl alcohol) gel. In this study, we optimized the conditions for removal of 137Cs from artificial contaminated water by the CS98 strain immobilized in agarose gel. The optimum ammonium acetate concentration, pH, temperature of the contaminated water, and cell density in the agarose gel were 5 mM, 8.5, 20-40 ｰC, and 3.6 ﾗ 109 cells per 2 mL of gel, respectively.

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The present study was to explore how friendship style is related to SNS stress in Japanese high school students. Some characteristics of friendship of modern Japanese adolescents were found in previous studies. SNS usage for LINE, Twitter, and Instagram were investigated. The data was collected by a questionnaire survey for first graders of a high school (n = 175). Cluster analysis yielded three friendship styles; adolescents who avoided a close friendship (avoidance style), those who participated in an emotionally close friendship (close-relationship style), and those who were careful not to hurt or be hurt by their friends and who tried just to enjoy time together with their friends (carefully-gathering style). SNS stress was compared as a function of cluster (i.e., friendship style). Adolescents of carefully-gathering style yielded higher tendency of compulsion to monitor SNS, anxiety of diffusion, and social comparison. Adolescents of close-relationship style were found to use many kinds of SNS and use LINE longer than the other styles, while their SNS stress was relatively weak. It was suggested that friendship style, rather than SNS usage, affects SNS stress.

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[in Japanese]

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Composite colorants that incorporate organic dye and suitable polymeric matrixes have drawn much interest in recent years. In this study, the nanoencapsulated organic dye are prepared by the phase inversion temperature (PIT) method, which is one of low energy emulsification methods. An o / w nanoemulsion having fine droplets by the PIT method can be prepared by utilizing the temperature characteristics of the polyoxyethylene type nonionic surfactant. Nanocapsules can be formed by thermally polymerizing this droplet. We prepared an emulsion of polyethylene glycol octadecyl ether (Brij S20) / ethylene glycol dimethacrylate (EGDMA) / ultrapure water system and prepared nanocapsules. In addition, we were succeeded in preparing nanocapsules containing organic dye.

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Recently, many libraries have introduced a UHF-band RFID tag system because of its convenience. However, the UHF-band RFID reader has wide coverage area and this can reduce the management efficiency by unintentionally reading unnecessary tags. In this paper, we propose an intelligent library gate by using machine learning algorithm. The intelligent gate takes into account relative angle and distance between RFID tags and the reader and controls the intensity of the radio wave emitted from the reader by using machine learning algorithm. This enables the reader to maintain detection accuracy and minimize electrical power consumption. In order to validate the effectiveness of the gate, SVM is used to predict RSSI. The result of the prediction shows RMSE as 7.67 and R-squared as 0.77. Electrical power consumption is reduced to 59 % compared to a case when the radio wave is emitted at maximum intensity. The result shows that the intelligent gate which maintains detection accuracy and minimize electrical power consumption can be developed by selecting minimum necessary radio wave intensity predicted in the experiment.

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In the synthesis of biologically active substance such as various pharmaceutical chemicals, amidation or esterification reaction is one of the most basic reactions. We developed effective amidating and the esterification method of having used sulfonyl halide. This method using this sulfonyl halide is expected to be widely used as a convenient and effective amidation esterification method in a region requiring mass synthesis etc. since the reaction reagent is inexpensive and excellent in operability.

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