The World robot summit disaster robotics category – achievements of the 2018 preliminary competition

The World Robot Summit is a robot Olympics and aims to be held in a different country every four years from 2020. The concept of the Plant Disaster Prevention challenge is daily inspections, checks, and emergency response in industrial plants, and in this competition, robots must carry out these types of missions in a mock-up plant. The concept of the Tunnel Disaster Response and Recovery challenge is emergency response to tunnel disasters, and is a simulation competition whereby teams compete to show their ability to deal with disasters, by collecting information and removing debris. The Standard Disaster Robotics challenge assesses, in the form of a contest, the standard performance levels of a robot that are necessary for disaster prevention and emergency response. The World Robot Summit Preliminary Competition was held at Tokyo Big Sight in October 2018, and 36 teams participated in the Disaster Robotics Category. UGVs and UAVs contended the merits of new technology for solving complex problems, using core technologies such as mobility, sensing, recognition, performing operations, human interface, autonomous intelligence etc., as well as system integration and implementation of strategies for completing missions, gaining high-level results.     

Active sites of Cu-ZSM-5 for the decomposition of acrylonitrile

The catalytic decomposition of acrylonitrile (AN) over Cu-ZSM-5 prepared with various Cu loadings was investigated. AN conversion, during which the nitrogen atoms in AN were mainly converted to N₂, increased as Cu loading increased. N₂ selectivities as high as 90–95% were attained. X-ray diffraction measurements (XRD) and temperature-programmed reduction by H₂ (H₂-TPR) showed the existence of bulk CuO in Cu-ZSM-5 with a Cu loading of 6.4 wt% and the existence of highly dispersed CuO in Cu-ZSM-5 with a Cu loading of 3.3 wt%. Electron spin resonance measurements revealed that Cu-ZSM-5 contains three forms of isolated Cu²⁺ ions (square-planar, square-pyramidal, and distorted square-pyramidal). The H₂-TPR results suggested that in Cu-ZSM-5 with a Cu loading of 2.9 wt% and below, Cu⁺ existed even after oxidizing pretreatment. The activity of AN decomposition over Cu/SiO₂ suggested that CuO could form N₂, but, independent of the CuO dispersion, nitrogen oxides (NO_x) were formed above 350 °C. Cu⁺ and the square-pyramidal and distorted square-pyramidal forms of Cu²⁺ showed low activity for AN decomposition. Temperature-programmed desorption of NH₃ suggested that N₂ formation from NH₃ proceeded on Cu²⁺, resulting in the formation of Cu⁺. The Cu⁺ ions were oxidized to Cu²⁺ at around 300 °C. Thus, high N₂ selectivity over Cu-ZSM-5 with a wide range of temperature was probably attained by the reaction over the square-planar Cu²⁺, which can be reversibly reduced and oxidized.     

Effect of ibudilast on microcirculation thrombosis in rat inner ear

Arterial wall thickening may be quantitatively assessed by measuring the intima-media thickness (IMT) with high resolution ultrasound. Previous studies have shown a good inter/intraobserver variability of IMT measurements in the common carotid. In this study we evaluated the inter/intraobserver variability of IMT measurements in 10 randomly selected asymptomatic subjects (age 55.4 +/- 6). Two carotids and two femorals were studied in each subject. IMT for each patient was the average of five IMT measurements at the artery bifurcation. Three observers repeated the scanning and the measurements twice with no knowledge of the previous readings. The between observer coefficient of variation (CV) was 8.45%; the intraobserver CV (mean of carotids and femorals) varied from 4.4 to 5.1% for the three observers who measured IMT three times. The mean absolute difference between the first and the third measurement was 0.0738 mm. In conclusion IMT measurement variability is mostly due to differences between observers. The intraobserver variability is very small. IMT measurements at the carotid and femoral bifurcations have a low variability and are a good expression of atherosclerosis as they consider early lesions at the bifurcation level which may not be observed in the common carotid.     

Antibacterial actin of vinegar against food-borne pathogenic bacteria including Escherichia coli O157:H7 (Part 2). Effect of sodium chloride and temperature on bactericidal activity

Bactericidal effects of various kinds of AWASEZU (processed vinegar, 2.5% acidity) on food-borne pathogenic bacteria including Escherichia coli O157:H7 and other bacteria were examined. the order of bactericidal activities was NIHAIZU (3.5% NaCl was added) > SANBA-IZU (3.5% NaCl and 10% sucrose were added) > plain vinegar (spirit vinegar) > AMAZU (10% sucrose was added). This indicates that their activities were enhanced by the addition of sodium chloride and suppressed by the addition of sugar. On the other hand, when soy sauce was used instead of sodium chloride, the order of bactericidal activities was plain vinegar > AMAZU > NIHAIZU > SANBAIZU. This is mainly because their activities were suppressed by the increase in the pH value. The effect of sodium chloride (0.01-15%) and temperature (10-50 degrees C) on bactericidal activities against E. coli O157:H7 in spirit vinegar (0.5-2.5% acidity) was further examined. When vinegar was used in combination with sodium chloride, predominant synergism on the bactericidal activity was observed. Their activities were markedly enhanced by the addition of sodium chloride in proportion to the concentration. In addition to this, at higher temperatures spirit vinegar killed bacteria much more rapidly. It should be noted that the bactericidal activity of spirit vinegar was extremely enhanced by the combined use of the addition of sodium chloride and the rise of temperature. For example, in 2.5% acidity vinegar, the time required for 3 log decrease in viable cell numbers at 20 degrees C was shortened to 1/140-fold by the addition of 5% sodium chloride, shortened to 1/51-fold by the rise of the reaction temperature at 40 degrees C, and shortened to 1/830-fold; 0.89 minutes by both the addition of 5% sodium chloride and the rise of temperature at 40 degrees C. In order to propose the methods to prevent food poisoning by bacterial infection, bactericidal activities of vinegar solution containing sodium chloride on cooking tools and raw vegetables were examined. Vinegar solution (1-2% acidity, 3-7% NaCl) produced more than 3 log decrease in viable cell numbers of E. coli O157:H7 on the surface of cutting board, and cabbage and cucumber at 20-50 degrees C. These results suggested that the treatment with vinegar solution containing sodium chloride may be one of the useful methods to prevent food poisoning.     

Bias-stress-induced increase in parasitic resistance of InP-based InAlAs/InGaAs HEMTs

The reliability of InP-based HEMTs is studied, focussing on how it is affected by the doped layer material and gate recess structure. Bias-and-temperature stress tests reveal that fluorine-induced donor passivation in the recess region, formed adjacent to the gate electrode, causes the source resistance (R_s) to increase at large drain bias voltages. The increase in R_s can be prevented by using InP or InAlP as the carrier supply layer material instead of InAlAs. On the other hand, the increase in the drain resistance (R_d) does not depend on the material of the carrier supply layer, which suggests that a mechanism different from that in the case of R_s should be considered. It is also found that a deep gate recess suppresses the increase in R_d after long-term stressing.     

Relationship between local immune response to Helicobacter pylori and the diversity of disease: investigation of H. pylori-specific IgA in gastric juice

In order to evaluate the relationship between local immune response to Helicobacter pylori and the diversity of disease, 77 asymptomatic subjects who underwent a health examination were studied. Helicobacter pylori-specific IgG in serum and H. pylori-specific IgA in gastric juice were measured by ELISA, and the measured IgA titre was classified into two grades, low or high. Histological classification of gastritis was performed according to the Sydney system. Cytokines in gastric juice were also measured, and the cytotoxin-associated gene A (cagA) status of H. pylori was tested by PCR. Of the 65 subjects who were positive for H. pylori-specific IgG in serum, 38 (58.5%) were classified as H. pylori-specific IgA low titre in gastric juice and 27 (41.5%) had high titres. In the IgG-positive, IgA-low group, the rate of peptic ulcers (especially duodenal ulcers) in endoscopic findings was higher (P < 0.05); the score of activity and the density of H. pylori were higher (P < 0.001 and P < 0.05, respectively); the score of metaplasia was lower (P < 0.05); and the level of interleukin-1 beta was lower (P < 0.05) than in the IgG-positive, IgA-high group. The positive rate of the cagA gene was 84.4% and there was no significant difference between the two groups. There were differences in endoscopic and histological findings between the IgG-positive, IgA-low and the IgG-positive, IgA-high groups. It is suggested that persons infected with H. pylori can be divided into two different states of disease according to local immune response.     

Design optimization of tall tubular lead/acid cells based on an analysis of the reaction distribution

In order to estimate the discharge performance of tall lead/acid cells (with tubular positives), changes in current and potential distributions with discharge progress were calculated with a computer on the basis of plate resistance and the current—potential—time relationship between small facing parts of positive and negative plates. The taller the cell, the larger the voltage drop along the plates. Thus, the discharge time became shorter despite a large amount of available active mass remaining in the bottom part of the plates.Various current-collector designs were evaluated, e.g., one with varying resistance at each height; a side conductor placed along the plates and connected to them at the top, centre and bottom, etc. Results revealed an optimum collector design with which the maximum discharge capacity could be obtained. Furthermore, it was shown that the side conductor markedly improved the discharge performance because the active mass near the connecting parts was appreciably used.     

Sinterability and properties of Ti(N1−x,O x ) y -(V,Ta)C-Ni sintered alloys having a golden colour

The effect of oxygen and carbide addition on the sinterability of TiN _y (0.42<y<1)-Ni alloys, in which part of the nitrogen is replaced by oxygen was investigated. It was found that sinterability increased as the oxygen and carbide content increased, but the strength of the resultant sintered alloys was significantly reduced due to the presence of Ni₃Ti and Ti₂O₃ phases when the oxygen content exceeded 50 mol %. The sintered alloy with the highest hardness was found whenx=0.7,y=0.78 and the (V,Ta)C content was 18% by weight and this alloy was characterized by having a low density, good corrosion resistance and the colour of gold.