著者
TAKESHI SANEKATA TOSHIAKI FUKUDA TAKANORI MIURA HIROFUMI MORINO CHEOLSUNG LEE KEN MAEDA KAZUKO ARAKI TORU OTAKE TAKUYA KAWAHATA TAKASHI SHIBATA
出版者
The Society for Antibacterial and Antifungal Agents, Japan
雑誌
Biocontrol Science (ISSN:13424815)
巻号頁・発行日
vol.15, no.2, pp.45-49, 2010 (Released:2010-07-05)
参考文献数
14
被引用文献数
32 65

We evaluated the antiviral activity of a chlorine dioxide gas solution (CD) and sodium hypochlorite (SH) against feline calicivirus, human influenza virus, measles virus, canine distemper virus, human herpesvirus, human adenovirus, canine adenovirus and canine parvovirus. CD at concentrations ranging from 1 to 100 ppm produced potent antiviral activity, inactivating ≥ 99.9% of the viruses with a 15 sec treatment for sensitization. The antiviral activity of CD was approximately10 times higher than that of SH.
著者
Takashi SHIBATA Kazunori SATO Ryohei IKEJIRI
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE Transactions on Electronics (ISSN:09168524)
巻号頁・発行日
vol.E100.C, no.11, pp.1012-1020, 2017-11-01 (Released:2017-11-01)
参考文献数
20
被引用文献数
2

We conducted experimental classes in an elementary school to examine how the advantages of using stereoscopic 3D images could be applied in education. More specifically, we selected a unit of the Tumulus period in Japan for sixth-graders as the source of our 3D educational materials. This unit represents part of the coursework for the topic of Japanese history. The educational materials used in our study included stereoscopic 3D images for examining the stone chambers and Haniwa (i.e., terracotta clay figures) of the Tumulus period. The results of our experimental class showed that 3D educational materials helped students focus on specific parts in images such as attached objects of the Haniwa and also understand 3D spaces and concavo-convex shapes. The experimental class revealed that 3D educational materials also helped students come up with novel questions regarding attached objects of the Haniwa, and Haniwa's spatial balance and spatial alignment. The results suggest that the educational use of stereoscopic 3D images is worthwhile in that they lead to question and hypothesis generation and an inquiry-based learning approach to history.
著者
Takashi SHIBATA Kazunori SATO Ryohei IKEJIRI
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE TRANSACTIONS on Electronics (ISSN:09168516)
巻号頁・発行日
vol.E100-C, no.11, pp.1012-1020, 2017-11-01

We conducted experimental classes in an elementary school to examine how the advantages of using stereoscopic 3D images could be applied in education. More specifically, we selected a unit of the Tumulus period in Japan for sixth-graders as the source of our 3D educational materials. This unit represents part of the coursework for the topic of Japanese history. The educational materials used in our study included stereoscopic 3D images for examining the stone chambers and Haniwa (i.e., terracotta clay figures) of the Tumulus period. The results of our experimental class showed that 3D educational materials helped students focus on specific parts in images such as attached objects of the Haniwa and also understand 3D spaces and concavo-convex shapes. The experimental class revealed that 3D educational materials also helped students come up with novel questions regarding attached objects of the Haniwa, and Haniwa's spatial balance and spatial alignment. The results suggest that the educational use of stereoscopic 3D images is worthwhile in that they lead to question and hypothesis generation and an inquiry-based learning approach to history.
著者
Koichi Shiraishi Takashi Shibata
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
pp.2021-005, (Released:2021-01-25)
被引用文献数
2

Stratospheric aerosols over the high Arctic at Ny Ålesund, Svalbard (79°N, 12°E) were observed continuously for four years from March 2014 by a lidar system using the second harmonic wavelength (532 nm) of the Nd:YAG laser. Our observations reveal the seasonal features of stratospheric aerosols and the arrival of the smoke at the high Arctic from Canadian forest-fire in August 2017. We estimated the seasonal variation for three years before the Canadian forest-fire when there was no apparent volcanic effect. In the estimation, we removed polar stratospheric clouds by the threshold temperature of their formation. The seasonal variation for the three years is that the vertical profiles of the backscattering ratio take a maximum value of about 1.05-1.06 at altitudes between 13 and 16 km from December to March, and about 1.02-1.04 at altitudes between 17 and 20 km from April to November. These results are compared with the results observed at the low Arctic, northern Norway. We also present the increases in the backscattering ratio and the volume depolarization ratio from September to December 2017 caused by the smoke from the Canadian forest-fire.
著者
Koichi Shiraishi Takashi Shibata
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
vol.17, pp.30-34, 2021 (Released:2021-02-23)
参考文献数
18
被引用文献数
2

Stratospheric aerosols over the high Arctic at Ny Ålesund, Svalbard (79°N, 12°E) were observed continuously for four years from March 2014 by a lidar system using the second harmonic wavelength (532 nm) of the Nd:YAG laser. Our observations reveal the seasonal features of stratospheric aerosols and the arrival of the smoke at the high Arctic from Canadian forest-fire in August 2017. We estimated the seasonal variation for three years before the Canadian forest-fire when there was no apparent volcanic effect. In the estimation, we removed polar stratospheric clouds by the threshold temperature of their formation. The seasonal variation for the three years is that the vertical profiles of the backscattering ratio take a maximum value of about 1.05-1.06 at altitudes between 13 and 16 km from December to March, and about 1.02-1.04 at altitudes between 17 and 20 km from April to November. These results are compared with the results observed at the low Arctic, northern Norway. We also present the increases in the backscattering ratio and the volume depolarization ratio from September to December 2017 caused by the smoke from the Canadian forest-fire.
著者
Atsushi Hinenoya Sharda Prasad Awasthi Noritomo Yasuda Ayaka Shima Hirofumi Morino Tomoko Koizumi Toshiaki Fukuda Takanori Miura Takashi Shibata Shinji Yamasaki
出版者
National Institute of Infectious Diseases, Japanese Journal of Infectious Diseases Editorial Committee
雑誌
Japanese Journal of Infectious Diseases (ISSN:13446304)
巻号頁・発行日
vol.68, no.4, pp.276-279, 2015 (Released:2015-07-22)
参考文献数
16
被引用文献数
8 21

In this study, we evaluated and compared the antibacterial activity of chlorine dioxide (ClO2) and sodium hypochlorite (NaClO) on various multidrug-resistant strains in the presence of bovine serum albumin and sheep erythrocytes to mimic the blood contamination that frequently occurs in the clinical setting. The 3 most important species that cause nosocomial infections, i.e., methicillin-resistant Staphylococcus aureus (MRSA), multidrug-resistant Pseudomonas aeruginosa (MDRP), and multidrug-resistant Acinetobacter baumannii (MDRA), were evaluated, with three representative strains of each. At a 10-ppm concentration, ClO2 drastically reduced the number of bacteria of all MDRP and MDRA strains, and 2 out of 3 MRSA strains. However, 10 ppm of NaClO did not significantly kill any of the 9 strains tested in 60 seconds (s). In addition, 100 ppm of ClO2 completely killed all MRSA strains, whereas 100 ppm of NaClO failed to significantly lower the number of 2 MRSA strains and 1 MDRA strain. A time-course experiment demonstrated that, within 15 s, 100 ppm of ClO2, but not 100 ppm of NaClO, completely killed all tested strains. Taken together, these data suggest that ClO2 is more effective than NaClO against MRSA, MDRP, and MDRA, and 100 ppm is an effective concentration against these multidrug-resistant strains, which cause fatal nosocomial infections.
著者
HIROFUMI MORINO TOSHIAKI FUKUDA TAKANORI MIURA CHEOLSUNG LEE TAKASHI SHIBATA TAKESHI SANEKATA
出版者
The Society for Antibacterial and Antifungal Agents, Japan
雑誌
Biocontrol Science (ISSN:13424815)
巻号頁・発行日
vol.14, no.4, pp.147-153, 2009 (Released:2010-02-23)
参考文献数
33
被引用文献数
22 29

The efficacy of gaseous chlorine dioxide (ClO2) against feline calicivirus (FCV), a norovirus surrogate, in the dry and the wet states on a hard surface was evaluated. We demonstrated that low-concentration ClO2 gas (mean 0.08 ppm, 0.22 μg/l) could inactivate FCV in the wet state with 0.5% fetal bovine serum (FBS) within 6 h in 45 to 55% relative humidity (RH) (>3 log10 reductions) and FCV in the dry state with 2% FBS (percentage of FBS in the viral suspension) within 10 h in 75 to 85% RH (>3 log10 reductions) at 20°C, respectively. Furthermore, a <0.3 ppm concentration of ClO2 gas (mean 0.26 ppm, 0.73 μg/l) could inactivate (below the detection limit) FCV in the dry state with 5% FBS within 24 h in 75 to 85% RH at 20°C. In contrast, in 45 to 55% RH at 20°C, ClO2 gas had little effect even when the FCV in the dry state was exposed to high-concentration ClO2 (mean 8 ppm, 22.4 μg/l) for 24 h. These results suggest that humidity plays an important role in the inactivation by ClO2 gas of FCV in the dry state. According to the International Chemical Safety Card, threshold limit values for ClO2 gas are 0.1 ppm as an 8-h time-weighted average and 0.3 ppm as a 15 min short-term exposure limit. From these data, we propose that the treatment of wet areas of human activity such as kitchens, toilets, etc., with low-concentration ClO2 gas would be useful for reducing the risk of infection by noroviruses (NV) without adverse effects. In addition, we believe that the application of a combination of a <0.3 ppm concentration of ClO2 gas and a humidifier in places without human activity may make it possible to inactivate NV in the dry state on any surface within a contaminated room without serious adverse effects.
著者
Atsushi Hinenoya Sharda Prasad Awasthi Noritomo Yasuda Ayaka Shima Hirofumi Morino Tomoko Koizumi Toshiaki Fukuda Takanori Miura Takashi Shibata Shinji Yamasaki
出版者
National Institute of Infectious Diseases, Japanese Journal of Infectious Diseases Editorial Committee
雑誌
Japanese Journal of Infectious Diseases (ISSN:13446304)
巻号頁・発行日
pp.JJID.2014.294, (Released:2015-01-20)
参考文献数
16
被引用文献数
9 21

In this study, we evaluated the antibacterial activity of chlorine dioxide (ClO2) compared with sodium hypochlorite (NaClO) on various multidrug-resistant strains in the presence of bovine serum albumin and sheep erythrocytes to mimic the frequent blood contamination in clinical environment. The 3 most important species causing nosocomial infections, i.e., methicillin-resistant Staphylococcus aureus (MRSA), multidrug-resistant Pseudomonas aeruginosa (MDRP) and multidrug-resistant Acinetobacter baumannii (MDRA) were evaluated, with 3 representative strains from each. At a 10 ppm-concentration, ClO2 drastically reduced the number of all MDRP and MDRA, and 2 out of 3 MRSA strains, but NaClO was unable to cause any remarkable attenuation for any of the 9 strains tested in 60 seconds. Increased concentration of 100 ppm enabled ClO2 to completely kill MRSA strains, whereas NaClO failed to significantly lower the number of 2 MRSA and 1 MDRA strains. A time-course experiment demonstrated that, within 15 seconds, 100 ppm of ClO2 could kill completely all tested strains but NaClO at this concentration failed to do so. Together, these data suggest that ClO2 is more effective than NaClO against MRSA, MDRP and MDRA, and 100 ppm could be a practical concentration of ClO2 against these multidrug-resistant strains, which may cause fatal nosocomial infections.