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Detection of norovirus from food borne outbreaks of gastroenteritis in Nagano Prefecture [Japan]
2004
Tokutake, Y.(Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Nakamura, Y. | Yokouchi, A. | Muramatsu, K. | Nishio, O.
Seasonal variation in airborne aerosol components in the central mountainous area, Japan
2003
Satsumabayashi, H. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Kawamura, M. | Katsuno, T. | Nishizawa, H. | Futaki, K. | Murano, K. | Ueda, H.
The seasonal variations of the chemical components in airborne aerosols in a mountainous area were investigated. Field observations were made at Happo at an altitude of 1,850m in the central mountainous region of Japan. Airborne aerosol was collected for 12hours or 24hours from May 1998 to September 1999 and the chemical components (Na+, Mg2+, K+, Ca2+, NH4+, Cl-, SO42-, NO3- and oxalic acid) in the aerosol were measured. In addition, gaseous pollutants, such as ozone and SO2 were monitored simultaneously. The concentrations of Na+ were much higher from autumn to spring than those in summer. Cl- increased in winter and the seasonal variation differed from Na+. The concentrations of Mg2+, K+ and Ca2+, especially Ca2+ increased in spring. It suggests that the increase in this Ca2+ concentration is based on the influence of Kosa aerosol (yellow sand) transported from continental Asia. The concentrations of SO42- and oxalic acid produced by photochemical reaction increased from spring to summer, and NH4+ which is the neutralization ingredient of sulfuric acid showed also the same seasonal variation. The concentration ratios of Cl-/Na+ were quite low compared with that of sea water. This is based on Cl- loss reaction. There was almost no influence of sea salt in the mountainous area, because most of K+, Ca2+ and SO42- were non-sea salt. The sulfate conversion ratio, i.e., SO42- -[S]/(SO2-[S] + SO42--[S]), was as high as 0.8 in summer. In summer and winter, when the concentration of SO42- was high, total equivalent concentration of anions (Cl-, NO3- and SO42-) was much higher than that of cations (Na+, NH4+, K+, Mg2+ and Ca2+), which suggests that a portion of the SO42- existed in the form of acidic aerosols such as H3SO4 and NH4HSO4. It suggests that a part of sulfuric acid produced by the photochemical reaction is transported to the mountainous area without being neutralized by alkali substances, such as NH3.
显示更多 [+] 显示较少 [-]Deposition of trace metals collected with bulk filtrate method in Nagano prefecture [Japan]
2003
Katsuno, T. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Shiozawa, K.
A survey of the environmental radiation in Nagano prefecture [Japan] from 1976 to 2000
2002
Nishizawa, C. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Yamaura, Y.
Behavior of airborne halocarbons in urban and highland areas of Nagano prefecture [Japan]
1999
Sasai, H. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Katsuno, T. | Nomizo, H. | Satsumabayashi, H.
Survey of river water acidification in Nagano prefecture [Japan]
1997
Miyajima, I. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Katsuno, T. | Takeda, Y. | Shiozawa, K.
Investigation on release of nitrogen and phosphorus from the sediments of different depth in Lake Suwa [Japan]
1987
Kono, Y. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Terasawa, J. | Harada, T. | Nasu, Y. | Kugimoto, M.
For the purpose of determining the effect of dredging on nutrients releasing from the sediment at the bottom of Lake Suwa after some of its sediment has been dredged, an experiment was performed to find out how much ammonium and phosphate would release from different depths of the sediment. Lake Suwa's sediment contains a lot of nitrogen and phoshorus down to its lower layers. The results of the experiment were as follows: The speed at which ammonium released from was faster as the depth of sediment increased. The speed at which ammonium was generated in the sediment showed the highest of 2.58N micro g/g dry sediment d in a 0-10cm layer. However, ammonium showed a generation speed of 1.3-1.4N micro g/g dry sediment-d at the depth of 10cm and more, indicating that ammonium easy to release from is generated even in lower layers. The speed at which phosphorus released from was 1.3-1.7Pmg/square m d in a 0-20cm deep layer, and 0.14-0.31Pmg/square m d at the depth of 20cm and more. The speed of Phosphorus releasing from lower layers of the sediment decreased to 1/4-1/10 of that in upper layers, and it was indicated that very little phosphorus flows out of the sediment at the depth of 20cm and more.
显示更多 [+] 显示较少 [-]The concentrations of boron, beryllium, antimony, selenium and vanadium in soils in Nagano prefecture [Japan]
1987
Seki, H. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Yanagimachi, Y. | Maruyama, M. | Nagase, K.
Secular variation of water quality of the hot spring sources in Akiyama-Gou [Japan]
2004
Takano, H.(Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Yamaura, Y. | Nishizawa, C. | Harada, T. | Taguchi, Y.
Epidemiological survey of tsutsugamushi disease [Rickettsia] in Nagano prefecture [Japan]
2003
Seki, E. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Muramatsu, K.