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31.
Ubiquity of parasporin-1 producers in <Emphasis Type="Italic">Bacillus thuringiensis</Emphasis> natural populations of Japan 总被引:1,自引:0,他引:1
Uemori A Maeda M Yasutake K Ohgushi A Kagoshima K Mizuki E Ohba M 《Die Naturwissenschaften》2007,94(1):34-38
Parasporin, a Bacillus thuringiensis parasporal protein, is unique in having a strong cytocidal activity preferential for human cancer cells. In this study, we
characterized parasporin activities associated with three novel geographical isolates of B.
thuringiensis. Parasporal inclusion proteins of the three isolates were highly toxic to human uterus cervix cancer cells (HeLa), but not
to non-cancer uterine smooth muscle cells (UtSMC). Inclusions of the isolates lacked insect toxicity and hemolytic activity
against sheep erythrocytes. Ouchterlony immunodiffusion tests revealed that the proteins of the three isolates are immunologically
closely related to parasporin-1 (Cry31A), but dissimilar to the three other existing parasporin groups. Our results provide
evidence that the parasporin-1-producing organism is a common member in B. thuringiensis populations occurring in natural environments of Japan. 相似文献
32.
ABSTRACT: Long term trends in Japan's annual and monthly precipitation are investigated in this study. The statistical significance of a trend at a study site is assessed by the Mann‐Kendall (MK) test, and field significance of trends in climatic Regions II, III, and IV is evaluated using the bootstrap test preserving cross correlation. The practical significance of a trend is judged by a percentage change of the sample mean over an observation period. The field significance assessment demonstrates that annual precipitation in Region II did not show any significant change, but regional precipitation shifts occurred in different months. Precipitation significantly increased by 12.2 percent in May, while it significantly decreased by 12.0, 10.5, 15.6, and 19.7 percent, respectively, in April, September, October, and December. In Region III, annual precipitation declined by 11.8 percent, and monthly precipitation significantly decreased from September through January and in April, with the greatest decrease (38.2 percent) in December. In Region IV, significant reductions occurred in both annual precipitation (by 15.6 percent) and monthly precipitation from September through February and in June and July, with the worst reduction (44.7 percent) in December. 相似文献
33.
We investigated the feeding habits and growth of juvenile stone flounder (Platichthys bicoloratus) in several estuarine nurseries in Sendai Bay, Japan. Prey abundance and composition and juvenile diet varied largely among
sites. However, polychaete palps (mostly Pseudopolydora kempi) and bivalve siphons (mostly Nuttallia olivacea) were positively selected and frequently consumed by juveniles, indicating the generality of sublethal feeding of juvenile
stone flounder in estuarine nurseries. Recent growth rates determined by otolith microstructure analyses were dependent on
juvenile body size and water temperature, but independent of juvenile density and food abundance. Growth rates were nearly
maximal from March to May, suggesting that food conditions are nearly optimal in these estuarine nurseries. Sublethal tissue
cropping of benthic invertebrates is thought to contribute largely to these high growth rates. 相似文献
34.
Global nuclear weapons tests fallout of 137Cs in the northern hemisphere has been documented in the UNSCEAR (United Nations Scientific Committee on the Effect of Atomic Radiation) reports. However, many questions have arisen during the past three to four decades; e.g. the water column inventory of 137Cs in the North Pacific Ocean was two to three time higher than the cumulative decay corrected fallout at the same latitude as stated in the UNSCEAR reports. Here we show more precise spatial distribution of global 137Cs fallout primarily on the basis of global measurements in rain, seawater and soil, as data from 10 degrees x 10 degrees grids. A typical feature of geographical distribution is that two high global 137Cs fallout areas exist in the northern hemisphere, where the highest 137Cs fallout was observed in the globe. These areas correspond to crossovers of areas where larger precipitation amounts were expected and where higher stratosphere-troposphere exchange was expected. Our new estimate of 765 +/- 79 PBq as global 137Cs fallout for the northern hemisphere is 1.4 times higher than that of 545 PBq in the UNSCEAR reports. 相似文献
35.
Yasuhito Igarashi Yayoi Inomata Michio Aoyama Katsumi Hirose Hiroshi Takahashi Yoshihiro Shinoda Nobuo Sugimoto Atsushi Shimizu Masaru Chiba 《Atmospheric environment (Oxford, England : 1994)》2009,43(18):2971-2980
Decades-long monitoring of anthropogenic radionuclides in the atmospheric deposition in Tsukuba, Japan suggests not only the substantial impacts of the Asian dust (Kosa) on the deposition but also the possible change of the Kosa source region, especially during springs of the 2000s. In order to know more about such change, 4 single wet deposition events occurred in the spring of 2007 were scrutinized. The largest anthropogenic radionuclides wet deposition was supplied by the April 2–4 event. It brought several tens % of the monthly depositions (April 2007) of the dust (residue) mass (4.5 g m?2) and anthropogenic radionulides (90Sr: 16, 137Cs: 97 and Pu: 3 mBq m?2). None of the events observed fulfilled both criteria of the specific activities and 90Sr/137Cs activity ratio to the Tsukuba soil; they did not exhibit local soil dust signature. The Kosa events in fact have extensive impacts on the atmospheric environment over Japan in spring season. Considering the elevated specific activities as well as greater 137Cs/90Sr activity ratio in the deposited dust, it is hypothesized that the dust source areas in Asian continent would be shifting from the arid zone to the desert-steppe zone suffering from desertification during the 2000s. This type of the Kosa may be called as the ‘new-regime Kosa’. Chemical observation in the far downwind region of the Kosa dust could allow us to know possible shift in the source regions. 相似文献
36.
Hirata SH Hayase D Eguchi A Itai T Nomiyama K Isobe T Agusa T Ishikawa T Kumagai M Tanabe S 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2789-2796
The present study measured the concentrations of 25 elements (Li, Mg, V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, In, Sn, Sb, Cs, Ba, Hg, Tl, Pb and Bi) in the whole body of Isaza which is an endemic fish species to Lake Biwa, Japan, and compared the values in the specimens from the mass mortality Isaza (MMI) and normal fresh Isaza (NFI). The mean levels of Mn and total As (T-As) were relatively higher in MMI than in NFI. In the T-As, highly toxic inorganic As was detected in MMI. Moreover we found Mn and As concentrations in surface sediment were extremely high and temporally increased. From all these results, we could infer that the dissolution of Mn and As from surface sediment of Lake Biwa might have been one of the cause for the mass mortality of Isaza. 相似文献
37.
The contribution of non-point sources to perfluorinated surfactants (PFSs) in a river was evaluated by estimating their fluxes and by using boron (B) as a tracer. The utility of PFSs/B as an indicator for evaluating the impact of non-point sources was demonstrated. River water samples were collected from the Iruma River, upstream of the intake of drinking water treatment plants in Tokyo, during dry weather and wet weather, and 13 PFSs, dissolved organic carbon (DOC), total nitrogen (TN), and B were analyzed. Perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), perfluoroheptanoate (PFHpA), perfluorooctanoate (PFOA), perfluorononanoate (PFNA), perfluorodecanoate (PFDA), perfluoroundecanoate (PFUA), and perfluorododecanoate (PFDoDA) were detected on all sampling dates. The concentrations and fluxes of perfluorocarboxylates (PFCAs, e.g. PFOA and PFNA) were higher during wet weather, but those of perfluoroalkyl sulfonates (PFASs, e.g. PFHxS and PFOS) were not. The wet/dry ratios of PFSs/B (ratios of PFSs/B during wet weather to those during dry weather) agreed well with those of PFS fluxes (ratios of PFS fluxes during wet weather to those during dry weather), indicating that PFSs/B is useful for evaluating the contribution from non-point sources to PFSs in rivers. The wet/dry ratios of PFOA and PFNA were higher than those of other PFSs, DOC, and TN, showing that non-point sources contributed greatly to PFOA and PFNA in the water. This is the first study to use B as a wastewater tracer to estimate the contribution of non-point sources to PFSs in a river. 相似文献
38.
We investigated perfluorinated surfactants (PFSs) in size-fractionated street dust to identify their occurrence, contributions from traffic, and potential routes of entry into waters. Street dust was collected from residential areas and heavily trafficked areas in Tokyo and sorted into fine (<63 microm) and coarse fractions (63-2000 microm). Five PFS species were analyzed by liquid chromatography-tandem mass spectrometry: perfluorooctanesulfonate (PFOS), perfluorooctanoate (PFOA), perfluorononanoate (PFNA), perfluorodecanoate (PFDA), and perfluoroundecanoate (PFUA). In fine fractions, PFS contents were significantly higher in heavily trafficked street dust than in residential street dust, but in coarse fractions, no significant differences were observed. Additionally, in heavily trafficked areas, PFS contents were significantly higher in fine fractions than in coarse fractions, but in residential areas, no significant differences were observed. PFS compositions differed between size fractions, not locations, indicating differences in sources between size fractions. Fine particles from traffic contributed to PFSs in street dust. Street dust possibly acts as the origin of PFSs in street runoff and eventually enters waters. This is the first report of PFSs in street dust. 相似文献
39.
Jan Pana Rabatho William Tongamp Yasushi Takasaki Kazutoshi Haga Atsushi Shibayama 《Journal of Material Cycles and Waste Management》2013,15(2):171-178
This paper describes a hydrometallurgical process for recovering neodymium (Nd) and dysprosium (Dy) from a magnetic waste sludge generated from the Nd–Fe–B(–Dy) manufacturing process. Phase analysis by XRD study revealed Nd(OH)3 and Fe2O3 as main mineral phases, and chemical analysis by ICP showed the contents of 35.1 wt% Nd, 29.5 wt% Fe, 1.1 wt% Dy and 0.5 wt% B. A solution of 1 M HNO3 + 0.3 M H2O2 was used to dissolve up to 98 % Nd and 81 % Dy, while keeping Fe dissolution below 15 % within 10 min. Fe dissolved in solution was completely removed as Fe(OH)3 at pH 3 followed by precipitation of Nd and Dy with oxalic acid (H2C2O4) and recovered 91.5 % of Nd and 81.8 % of Dy from solution. The precipitate containing Nd and Dy was calcined at 800 °C to obtain Nd2O3 as final product with 68 % purity, and final recovery of 69.7 % Nd and 51 % of Dy was reported in this process. 相似文献
40.