Induction of adaptive response <i>in utero </i>by ionizing radiation: A radiation quality dependent phenomenon

Investigation on possible induction of adaptive response (AR) by high-liner energy transfer (LET) particleradiation for protection against low-LET photon radiation-induced detrimental effects has not yet been performed inutero. This study verified if an AR could be induced by high-LET particle radiation from accelerated heavy ionsagainst low-LET X-ray radiation-induced detrimental effects on fetal mice. Total body irradiation of pregnantC57BL/6J mice were performed by delivering a priming dose ranging from 10 mGy to 320 mGy of particle radiationon gestation day 11 followed one day later by a challenge dose at 3500 mGy from X-ray radiation. The monoenergeticbeams of carbon, silicon and iron with the LET values of about 15, 55, and 200 KeV/μm, respectively, were examined.Significant suppression by the priming radiation of the detrimental effects (fetal death, malformation, or low bodyweight) was used as the endpoints for judgment of a successful AR induction on gestation day 18. Existence of ARwas not observed. On the other hand, the priming dose of high-LET particle radiation, in some cases, even increasedthe detrimental effects induced by the challenge dose from low-LET X-ray radiation. Although existence of ARinduced by high-LET radiation in cultured mammalian cells in vitro and in certain tissues of laboratory mice in vivowas demonstrated, the present study did not suggest that low dose of high-LET particle radiation could induce an ARin fetal mice inutero under the setup of our experimental system.     

Analysis of Measured Data in Unbalanced Distribution System and Method of Making of Distribution System Model for Analyzing

In recent years, rapid introduction of photovoltaic power systems (PVs) causes voltage rise in distribution systems. In addition, residential PVs cause voltage unbalance in distribution systems. For these reasons, it has become difficult to control voltage in distribution systems to within the allowable range. Therefore, it is necessary to consider the voltage unbalance suppression method corresponding to the measured data in unbalanced distribution systems. Thus, we measured voltage on the distribution lines that are expected to large voltage imbalance and analyzed the reality of voltage unbalance. Also, static VAR compensator is suitable for voltage unbalance suppression, although it is expensive. Therefore, we make the distribution system model using the measured voltage in distribution systems to verify the voltage unbalance suppression effect.     

Aflatoxin Contamination in Nutmeg: Analysis of Interfering TLC Spots

When a mixture of ground nutmeg and ground cinnamon leaves was subjected to thin layer chromatography (TLC), spots that hampered detection of aflatoxins appeared on the TLC plate. These spots represented oxidation or heat-induced degeneration products of the cinnamon leaves. Between 1986 and 1991, 67 samples of nutmeg, that were commercially available in Japan, were examined for aflatoxin contamination. Aflatoxins were detected in 29 (43%) of the 67 samples.     

New Drive Circuit for Reducing the Switching Current Ripples in Switched Reluctance Motors

This paper proposes a new drive circuit for reducing the switching current ripples in a switched reluctance motor (SRM). The authors have already presented an instantaneous flat torque control for SRMs, and confirmed its effectiveness through experimental results. However, the switching current ripples also cause torque ripples, and therefore, the current ripples should be decreased to reduce the torque ripples even more. The proposed circuit with parallel capacitor can realize such a reduction. The validity of the proposed drive circuit is verified experimentally.     

Transient Electric Field Analysis in Consideration of the Electric Field Dependence of Resistivity in the Converter Transformer

In this paper, values of the electric field in the pressboard and oil during the polarity reversal test of the converter transformer were calculated with transient analysis. First, we confirmed the accuracy of the nonlinear analysis in the model test. Next, we carried out nonlinear transient electric field analysis for polarity reversal test of the converter transformer. In the results, when the applied time of dc voltage before the polarity reversal is 360 min, the values of the electric field of oil area are the same as when it is 90 min. Although, the electric field in the pressboard becomes higher in response to the applied time dc voltage, it does not cause a problem on the insulation. Because withstand voltage of pressboard is very high. In the results, the correlation between the applied time of dc voltage before the polarity reversal and the withstand voltage of transformer is considered low. This result can be applied to the design of the converter transformer.