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31.
Elevated serum vitellogenin levels and gonadal abnormalities in wild male flounder (Pleuronectes yokohamae) from Tokyo Bay, Japan. 总被引:8,自引:0,他引:8
S Hashimoto H Bessho A Hara M Nakamura T Iguchi K Fujita 《Marine environmental research》2000,49(1):37-53
Concentrations of vitellogenin (VTG) in serum of wild male flounder (Pleuronectes yokohamae) were investigated, as a biomarker for environmental estrogens in marine waters, from January 1997 to May 1998 in Tokyo Bay, Japan (n = 130) and from a reference site in Hokkaido, Japan, far from urban areas (about 40 km from Hakodate city) from March 1997 to June 1998 (n = 62). Statistically higher concentrations of serum VTG were detected in wild male flounder collected in Tokyo Bay (range: 25-2200 ng ml-1) compared to fish from Hokkaido (range: 31-91 ng ml-1) throughout the entire sampling period. Three out of 20 males collected off Haneda, in the inner part of Tokyo Bay, showed testes containing small numbers of oocytes. This intersex condition was not found among males collected from the reference site. This study suggests that the abnormally high levels of VTG and the presence of oocytes in the testis of male flounder collected from Tokyo Bay could be the effect of environmental estrogens. 相似文献
32.
33.
Nobuo Sugimoto Yukari Hara Atsushi Shimizu Tomoaki Nishizawa Ichiro Matsui Masataka Nishikawa 《Asia-Pacific Journal of Atmospheric Sciences》2013,49(1):27-39
The Asian dust events in 2008 (May 24–June 4 in 2008) and in 2009 (March 12–25, October 13–26, and December 15–28 in 2009) were analyzed with the lidar network observations, surface observations in China, Korea, Japan, and Mongolia, and with the chemical transport model CFORS. Transport of Asian dust and mixing of dust with air pollution aerosols were studied. The event of May 24 to June 4 in 2008 was a significant event unusually late in the spring dust season. The dust event of March 12–25, 2009 was an interesting example of elevated dust layer, and transport of dust from the elevated dust layer to the ground by the boundary layer activity was observed with the lidars and surface observations in Japan. The concentration of air pollution aerosols was relatively high during the dust event, and the results suggest that vertical structure as well as transport path is important for the mixing of dust and air pollution aerosols. The dust events in October and December 2009 were examples of dust events in autumn and winter. The online mode CFORS reproduced the observation data generally well, except for the event of May 24 to June 4 in 2008. The results of the fourdimensional variational assimilation of the lidar network data reproduced the dust concentration in Korea and Japan reasonably in that event. 相似文献
34.
Abstract It has been observed that earthquake‐induced settlement depends on the excess pore water pressure accumulated during an earthquake. In particular, in the case where a clay layer is overconsolidated, excess pore water pressure is produced and settlement occurs by dissipation of the excess pore water pressure, which is very large in comparison with the coefficient of secondary compression. Therefore, if the settlement of clay ground induced by secondary compression becomes a serious problem, careful consideration of the earthquake‐induced settlement is needed. In this article, the settlement characteristics of a clay layer induced by cyclic shear are discussed, including the effects of loading period, the threshold shear strain below which no excess pore pressure or no settlement takes place, and the relationships between uniform shear strain cycles and irregular strain‐time histories. Then a calculation procedure for estimating the earthquake‐induced settlement is developed and applied to three soil profile cases, including the clay layers in Mexico City and Osaka Bay in Japan. In the case of a soil profile in Mexico City, settlements of about 0–3 cm are estimated and these values agree reasonably with the leveling results for the Mexico City earthquake of 1985. Furthermore, it is pointed out that the settlement induced by earthquakes is considerably affected by differences in the accelerograms. 相似文献
35.
36.
Yui Kouketsu Tomoyuki Mizukami Hiroshi Mori Shunsuke Endo Mutsuki Aoya Hidetoshi Hara Daisuke Nakamura Simon Wallis 《Island Arc》2014,23(1):33-50
The Raman spectra of carbonaceous material (CM) from 19 metasediment samples collected from six widely separated areas of Southwest Japan and metamorphosed at temperatures from 165 to 655°C show systematic changes with metamorphic temperature that can be classified into four types: low‐grade CM (c. 150–280°C), medium‐grade CM (c. 280–400°C), high‐grade CM (c. 400–650°C), and well‐crystallized graphite (> c. 650°C). The Raman spectra of low‐grade CM exhibit features typical of amorphous carbon, in which several disordered bands (D‐band) appear in the first‐order region. In the Raman spectra of medium‐grade CM, the graphite band (G‐band) can be recognized and several abrupt changes occur in the trends for several band parameters. The observed changes indicate that CM starts to transform from amorphous carbon to crystallized graphite at around 280°C, and this transformation continues until 400°C. The G‐band becomes the most prominent peak at high‐grade CM suggesting that the CM structure is close to that of well‐crystallized graphite. In the highest temperature sample of 655°C, the Raman spectra of CM show a strong G‐band with almost no recognizable D‐band, implying the CM grain is well‐crystallized graphite. In the Raman spectra of low‐ to medium‐grade CM, comparisons of several band parameters with the known metamorphic temperature show inverse correlations between metamorphic temperature and the full width at half maximum (FWHM) of the D1‐ and D2‐bands. These correlations are calibrated as new Raman CM geothermometers, applicable in the range of c. 150–400°C. Details of the methodology for peak decomposition of Raman spectra from the low to medium temperature range are also discussed with the aim of establishing a robust and user‐friendly geothermometer. 相似文献
37.
Temporal trends in wet deposition of major ions were explored at nationwide remote sites in Japan from April 1991 to March 2009 by using the seasonal Kendall slope estimator and the nonparametric seasonal Kendall test. For the trend analysis, datasets from eight remote sites (Rishiri, Echizenmisaki, Oki, Ogasawara, Shionomisaki, Goto, Yakushima, and Amami) were selected from the Japanese Acid Deposition Survey (JADS) conducted by the Ministry of the Environment. Deposition of H+ has been increasing at remote sites in Japan on a national scale. Significant (p????0.05) increases in H+ deposition were detected with changes of +3?C+9?%?year?1 at seven sites, while insignificant increases were observed at one site. Depositions of non-sea salt (nss)-SO 4 2? and NO 3 ? significantly increased at four and six sites, respectively, with changes of +1?C+3?%?year?1. Significant increases in precipitation at four sites would have contributed to the increase in depositions of H+, nss-SO 4 2? , and NO 3 ? . The emission trends of SO2 and NOx did not corresponded to the deposition trends of nss-SO 4 2? and NO 3 ? . The different trends indicated that temporal variation of precipitation amount trend dominated the deposition trends. 相似文献
38.
Operational discharges of hydrocarbons from maritime activities can have major cumulative impacts on marine ecosystems. Small quantities of oil (i.e., 10 ml) results in often lethally reduced thermoregulation in seabirds. Thin sheens of oil and drilling fluids form around offshore petroleum production structures from currently permissible operational discharges of hydrocarbons. Methodology was developed to measure feather microstructure impacts (amalgamation index or AI) associated with sheen exposure. We collected feather samples from two common North Atlantic species of seabirds; Common Murres (Uria aalge) and Dovekies (Alle alle). Impacts were compared after feather exposure to crude oil and synthetic lubricant sheens of varying thicknesses. Feather weight and microstructure changed significantly for both species after exposure to thin sheens of crude oil and synthetic drilling fluids. Thus, seabirds may be impacted by thin sheens forming around offshore petroleum production facilities from discharged produced water containing currently admissible concentrations of hydrocarbons. 相似文献
39.
A probabilistic approach to exposure risk assessment 总被引:1,自引:1,他引:0
Crispin M. Mutshinda Imoh Antai Robert B. O’Hara 《Stochastic Environmental Research and Risk Assessment (SERRA)》2008,22(4):441-449
The introduction of hazardous substances into the environment has long been recognized as being a cause of several diseases
in humans, wildlife, and plants. The damaging character of suspected contaminants is usually assessed via a “reject/retain”
design with no explicit link between levels of exposure and intensities of the potential adverse health effects even though
this connection may be important for the development of public health regulations that limit exposure to hazardous substances.
Here, we propose a probabilistic approach to exposure risk assessment as a way around this typical flaw. We develop a Bayesian
model using proximity to the source of an alleged contaminant as a surrogate for exposure. Subsequently, we carry out an experimental
study based on simulated data to illustrate the model implementation with real world data. We also discuss a possible way
of extending the model to accommodate potential heterogeneity in the spatial distribution of the focal disease. 相似文献
40.
G. Giono R. Ishikawa N. Narukage R. Kano Y. Katsukawa M. Kubo S. Ishikawa T. Bando H. Hara Y. Suematsu A. Winebarger K. Kobayashi F. Auchère J. Trujillo Bueno S. Tsuneta T. Shimizu T. Sakao J. Cirtain P. Champey A. Asensio Ramos J. Štěpán L. Belluzzi R. Manso Sainz B. De Pontieu K. Ichimoto M. Carlsson R. Casini M. Goto 《Solar physics》2017,292(4):57
The Chromospheric Lyman-Alpha SpectroPolarimeter is a sounding rocket instrument designed to measure for the first time the linear polarization of the hydrogen Lyman-\({\upalpha }\) line (121.6 nm). The instrument was successfully launched on 3 September 2015 and observations were conducted at the solar disc center and close to the limb during the five-minutes flight. In this article, the disc center observations are used to provide an in-flight calibration of the instrument spurious polarization. The derived in-flight spurious polarization is consistent with the spurious polarization levels determined during the pre-flight calibration and a statistical analysis of the polarization fluctuations from solar origin is conducted to ensure a 0.014% precision on the spurious polarization. The combination of the pre-flight and the in-flight polarization calibrations provides a complete picture of the instrument response matrix, and a proper error transfer method is used to confirm the achieved polarization accuracy. As a result, the unprecedented 0.1% polarization accuracy of the instrument in the vacuum ultraviolet is ensured by the polarization calibration. 相似文献