Measurement and Analysis of Electromyography for Sequential Mastication

　In the palatability of food, texture is a major factor of food quality. The physical shear force value of meat has been measured. However, quantitative relationship and characterization between shear force value and tenderness as a sensory perception has not been clear. Therefore, a computer system was developed to analyze and to measure the electromyography (EMG) for mastication. 　The integral EMG values were almost constant by sequential mastication up to five times. The average of integral EMG values were 63.6 mV with tender meat of pork fillet and 153.8 mV with firm meat of beef round, giving a ratio of 2.4 times. The shear force values of similar samples were 2,300 g and 8,300 g each, and the ratio was 3.6 times. Sensory texture of the subjective feeling was 3ﾝ4 times that corresponded with the shear force value. The integral EMG value could be thought to compress the amount of texture sense. 　The integral EMG varied greatly in food, and showed lower value in order of boiled fish surimi, steamed fish paste, pork sausage, konnyaku (devil’s tongue), pork fillet, beef loin, pork ham portion, roast beef, pork loin and beef round. Generally this order reflected the sensory texture of chewing. The deviation of the integral EMG value was smaller than expected, so it has a definite possibility for practical use

The Porosity and Mechanical Properties of H13 Tool Steel Processed by High-Speed Selective Laser Melting

Additive Manufacturing (AM) technology has the advantages of complicated geometry fabrication and integration of multiple parts. Selective Laser Melting (SLM), which is one of the AM technologies, generally takes longer manufacturing time than other manufacturing methods. In this research, the process parameters, which can achieve high-speed additive manufacturing of H13 tool steel, are investigated using a SLM machine with a 1 kW multi-mode fiber laser. As a result, the optimal process window has been determined in the process map of the laser power and the scan speed. High laser power in the process window is estimated to increase the manufacturing speed by 50 % of that with the conventional parameters. The specimen manufactured with the optimal parameters has a tensile strength of 1500 MPa, which is equivalent to the bulk samples.Mechanical Engineerin

Meta-Analysis of Secondary Cancer in Childhood Cancer Survivors

Background: Cancer risks following radiotherapy have not been well characterized in terms of radiation dose. Before we have conducted a meta-analysis of studies on the excess relative risk per Gy (ERR) of second malignant neoplasm (SMN) among childhood cancer survivors, but the small number of eligible studies restricted quantitative evaluations. To solve this problem, we developed a statistical method to calculate an ERR estimate from other estimates, and conducted a meta-analysis again. Materials and Methods: We searched the PubMed database, and 21 studies were identified. ERR estimates were available in 10 studies, and for the rest 11 studies, we used the regression-based model to calculate a ERR estimate from other estimates. The overall ERR estimates of radiotherapy were calculated using a random effects model. Results and Discussion: The ERR estimates from 21 studies ranged from 0.004 to 11.7. The overall ERR was 0.45 (95%CI: 0.21, 0.97), which was far smaller than the corresponding estimate of 1.7 from the study on atomic bomb survivors exposed as young children. Heterogeneity was suggested by Cochran\u27s Q statistics (Q=188, DF=20, p<0.001). The reason for heterogeneity will be explored.WHO satellite meeting "Radiation risk assessment in pediatric healthcare" in KIDS Workshop 2009 in NIR

Meta-Analysis of Second Cancer Risk after Radiotherapy among Childhood Cancer Survivors

We have conducted a meta-analysis of studies on the excess relative risk per Gy (ERR) of second cancer before, but the small number of eligible studies restricted quantitative evaluations. To solve this problem, a method to calculate ERR per Gy estimates from another form of estimates was developed, and a meta-analysis was conducted again. We searched the PubMed database, and 26 studies were identified. ERR per Gy estimates were available in 15 studies, and for rest 11 studes, we used the regression model to calculate ERR per Gy estimates from other estimates. The overall ERR per Gy estimate was 0.61 (95% CI: 0.31, 1.2), which was much lower than that of atomic bomb survivors exposed as young children (1.7; 95%CI: 1.1, 2.5). Heterogeneity of the ERR per Gy estimates among studies was suggested, and the reasons were explored. It was suggested that ERR per Gy estimates in the different SMN sites differed greatly, and they also decreased to 0.88 time by one year increase in primary cancer age. The heterogeneity could be explained by the SMN sites and primary cancer age to some extent.The Third Asian and Oceanic Congree on Radiation Protectio

Effect of Topography on Glossiness and Surface Color for a 5052 Aluminum Alloy * 1

The effect of topography on the glossiness and surface color of aluminum alloy A5052 specimens was experimentally investigated. The surfaces of the specimens were machined using either a vertical milling machine, a horizontal milling machine or a shaping machine. Four specimens were produced by each machine so that the arithmetical mean roughness value, Ra, was less than 1 mm under four different cutting conditions. The experimental results revealed that the vertical and horizontal milling glossiness values were nearly the same, while the glossiness values of the shaped surface was less than half of this value. The surface color of all of the specimens was gray, although the lightness value of the surface color, L Ã , for the horizontal milling surface had the highest value. Based on the experimental results, it was determined that the surface texture of specimens produced by these machines could be characterized by their glossiness and surface color. These results could prove an effective indicator for choosing the most appropriate machining method by providing surface texture values