A cDNA microarray technique applied for analysis of global gene expression profiles in tributyltin-exposed ascidians   总被引：2，自引：0，他引：2  

Azumi K  Fujie M  Usami T  Miki Y  Satoh N 《Marine environmental research》2004,58(2-5):543-546

To analyze global gene expressions, we constructed a cDNA microarray from a basal chordate, the ascidian Ciona intestinalis. Ciona is a cosmopolitan species and a genomic analysis of Ciona revealed that ascidians had approximately 15,500 protein-coding genes. Our "Ciona intestinalis cDNA chip version 1 (Ci cDNA chip ver. 1)" has arrayed 13,400 unique Ciona cDNAs. To establish a detection system for gene expression profiles in wild ascidians using a cDNA microarray, we analyzed gene expressions in the whole body of Ciona adults after exposure to 100 nM tributyltin (TBT) for 24 h. In our preliminary array data using Ci cDNA chip ver. 1, we found more than 200 genes that showed strong differential expressions. These genes encoded proteins that were concerned with stress response, detoxification, oxidoreduction reaction, biosynthesis, and catabolism. This, the first large cDNA microarray of this animal, should facilitate analyses of global gene expressions following exposure to TBT.  相似文献   

Fluctuation of the sea surface dynamic topography southeast of Japan as estimated from Seasat altimetry data     

Kaoru Ichikawa  Shiro Imawaki 《Journal of Oceanography》1992,48(2):155-177

The sea surface dynamic topography (the sea surface height relative to the geoid; hereafter abbreviated SSDT) can be divided into the temporal mean SSDT and the fluctuation SSDT around the mean. We use the optimal interpolation method to reduce the satellite radial orbit error and estimate the fluctuation SSDT southeast of Japan from Seasat altimetry data during the 17-day near-repeat mission. The fluctuation SSDT is further combined with the mean geopotential anomalies estimated from hydrographic data during the Seasat mission in order to give the approximated total SSDT, called here the composite SSDT (the approximated mean plus fluctuation SSDT's). The fluctuation SSDT is in accord with the low-frequency sea-level fluctuation recorded at tide gauge stations in the Japanese islands. The composite SSDT describes thoroughly variations of the location of the Kuroshio axis south of Japan determined on the basis of the GEK (Geomagnetic Electro-Kinematograph) surface velocities and the horizontal temperature distribution. The composite SSDT also agrees with oceanic variations east of Japan found in the temperature distribution at the depth of 200 m. These results confirm that the SSDT derived from altimetry data can provide fairly precise synoptic views of low-frequency oceanic phenomena.  相似文献   

Estimating the geostrophic velocity obtained by HF radar observations in the upstream area of the Kuroshio     

Ryoko Tokeshi  Kaoru Ichikawa  Satoshi Fujii  Kenji Sato  Shoichiro Kojima 《Journal of Oceanography》2007,63(4):711-720

A method to extract geostrophic current in the daily mean HF radar data in the Kuroshio upstream region is established by comparison with geostrophic velocity determined from the along-track altimetry data. The estimated Ekman current in the HF velocity is 1.2% (1.5%) and 48° (38°)-clockwise rotated with respect to the daily mean wind in (outside) the Kuroshio. Furthermore, additional temporal smoothing is found necessary to remove residual ageostrophic currents such as the inertial oscillation. After removal of the ageostrophic components, the HF geostrophic velocity agrees well with that from the altimetry data with rms difference 0.14 (0.12) m/s in (outside) the Kuroshio.  相似文献   

GPS-measured land subsidence in Ojiya City, Niigata Prefecture, Japan   总被引：1，自引：0，他引：1  

Hiroshi P. Sato  Kaoru Abe  Osamu Ootaki 《Engineering Geology》2003,67(3-4):379-390

Land subsidence caused by compression of clay layers in Ojiya City, Japan was measured by global positioning system (GPS) between 1 April 1996 and 31 December 1998.

Three baselines were selected in and around the city, and height difference on a WGS-84 ellipsoid was measured by GPS on each baseline. The ground at the GPS station in the city subsides and rebounds 7 cm every winter and spring, respectively. Measurement accuracy was 9.5 mm standard deviation. Ground water level was observed at a well near the GPS station. Regression analysis between total strain, calculated as ratio of the height difference displacement to the total thickness of the clay layers, and the layers' effective stress change with ground water level change gave good correlation. The slope of regression line 7.0×10⁻¹¹ m²/N was obtained as an average apparent coefficient of volume compressibility of the layers.  相似文献   

Chemical, Isotopic, and Fluid Inclusion Evidence for the Hydrothermal Alteration of the Footwall Rocks of the BIF-Hosted Iron Ore Deposits in the Hamersley District, Western Australia     

Makoto Haruna    Takahiro Hanamuro    Kaoru Uyeda    Hirokazu Fujimaki  Hiroshi Ohmoto 《Resource Geology》2003,53(2):75-88

Abstract. The petrography, chemical, fluid inclusion and isotope analyses (O, Rb-Sr) were conducted for the shale samples of the Mount McRae Shale collected from the Tom Price, Newman, and Paraburdoo mines in the Hamersley Basin, Western Australia. The Mount McRae Shale at these mines occurs as a footwall unit of the secondary, hematite-rich iron ores derived from the Brockman Iron Formation, one of the largest banded iron formations (BIFs) in the world. Unusually low contents of Na, Ca, and Sr in the shales suggest that these elements were leached away from the shale after deposition. The δ¹⁸O (SMOW) values fall in the range of + 15.0 to +17.9 per mil and show the positive correlation with calculated quartz/sericite ratios of the shale samples. This suggests that the oxygen isotopic compositions of shale samples were homogenized and equilibrated by postdepositional event. The pyrite nodules hosted by shales are often rimmed by thin layers of silica of varying crystallinity. Fluid inclusions in quartz crystals rimming a pyrite nodule show homogenization temperatures ranging from 100 to 240C for 47 inclusions and salinities ranging from 0.4 to 12.3 wt% NaCl equivalent for 18 inclusions. These fluid inclusion data give direct evidence for the hydrothermal activity and are comparable to those of the vein quartz collected from the BIF-derived secondary iron ores (Taylor et al, 2001). The Rb-Sr age for the Mount McRae Shale is 1,952 ± 289 Ma and at least 200 million years younger than the depositional age of the Brockman Iron Formation of ∼ 2.5 Ga in age. All the data obtained in this study are consistent with the suggestion that high temperature hydrothermal fluids were responsible for both the secondary iron ore formation and the alteration of the Mount McRae Shale.  相似文献   

Factors controlling typhoons and storm rain on the Korean Peninsula during the Little Ice Age   总被引：1，自引：0，他引：1  

Kota Katsuki  Dong-Yoon Yang  Koji Seto  Moriaki Yasuhara  Hiroyuki Takata  Masashi Otsuka  Toshimichi Nakanishi  Yoonyeol Yoon  In-Kwon Um  Richard C. W. Cheung  Boo-Keun Khim  Kaoru Kashima 《Journal of Paleolimnology》2016,55(1):35-48

  相似文献   

Uranium, Thorium and Potassium Contents In Eighteen Geochemical Reference Samples Issued from the Geological Survey of Japan     

Kazuhisa KOMURA  Kok-Leong TAN  Kaoru UENO 《Geostandards and Geoanalytical Research》1988,12(2):371-374

Uranium, thorium and potassium contents in eighteen geochemical reference samples issued from the Geological Survey of Japan have been measured by non-destructive gamma-ray spectrometry using germanium semiconductor detectors. Results are generally in good agreement with recent values measured by various methods.  相似文献   

Hypocenter distribution and focal mechanism of AE events during two stress stage creep in Yugawara andesite     

Osamu Nishizawa  Kaoru Onai  Kinichro Kusunose 《Pure and Applied Geophysics》1984,122(1):36-52

More than a thousand acoustic-emission (AE) hypocenters were determined in a cylindrical andesite specimen under two-stage uniaxial creep at stresses of 204 and 214 MPa. Strains were monitored for 6 peripheral points at the middle part of the cylindrical specimen's wall. The strain data indicate gradual increase of nonuniform deformation during steady creep and strong intensification of the nonuniformity during acceleration creep and, therefore, biased stress distribution within the specimen. The correlation between dilatant strain and AE hypocenters was investigated for whether or not tensile cracks emit AE. The region with high AE activity shows only a small dilatant strain. This negative correlation between AE and the dilatant region may eliminate tensile cracks as possible AE sources. A composite focal-mechanism solution of local AE events, covering a wide solid angle of the focal hemisphere, indicates that shear fractures emit AE waves. The direction of the compressional axis in this solution shows a significant deviation from that inferred from the applied external force, suggesting that the local stress field is governed by preexisting weak zones that are, presumably, produced by tensile cracks within the specimen. AE hypocenters tended to form clusters during steady creep under the constant compressional stress. During acceleration creep caused by a small step increase of the external stress, the preceding clusters disappeared while a new cluster appeared in an incipient fault plane. This suggests that changes in seismicity pattern such as migrations or quiescences of swarm—important clues for earthquake predictions—may be caused by an instantaneous change in the tectonic-stress levels.  相似文献   

Crustal structure in and around the region of the 1995 Kobe Earthquake deduced from a wide-angle and refraction seismic exploration     

Takeshi Ohmura  Takeo Moriya  Chengshi Piao  Takaya Iwasaki  Toshikastu Yoshi  Shin'ichi Sakai  Tetsuya Takeda  Kaoru Miyashita  Humihito Yamazaki  Kiyoshi Ito  Akira Yamazaki  Yoji Shimada  Katsuya Tashiro  Hiroki Miyamachi 《Island Arc》2001,10(3-4):215-227

Abstract The 1995 Kobe (Hyogo-ken Nanbu) earthquake (M_JMA 7.2, M_w 6.9) occurred on Jan. 17, 1995, at a depth of 17 km, beneath the areas of southern part of Hyogo prefecture and Awaji Island. To investigate P-wave velocity distribution and seismological characteristics in the aftershock area of this great earthquake, a wide-angle and refraction seismic exploration was carried out by the Research Group for Explosion Seismology (RGES) . The profile including 6 shot points and 205 observations was 135 km in length, extending from Keihoku, Northern Kyoto prefecture, through Kobe, to Seidan on Awaji Island. The charge of each shot was 350–700 kg. The P-wave velocity structure model showed a complicated sedimentary layer which is shallower than 2.5 km, a 2.5 km-thick basement layer whose velocity is 5.5 km/s, overlying the crystalline upper crust, and the boundary between the upper and lower crust.
Almost all aftershock hypocenters were located in the upper crust. However, the structure model suggests that the hypocenters of the main shock and some aftershock clusters were situated deeper than the boundary between the upper and lower crust. We found that the P-velocity in the upper crust beneath the northern part of Awaji Island is 5.64 km/s which is 3% lower than that of the surrounding area. The low-velocity zone coincides with the region where the high stress moment release was observed.  相似文献   

Amino acid precursors in lunar fines: limits to the contribution of jet exhaust     

Sidney W. Fox  Kaoru Harada  P.E. Hare 《Geochimica et cosmochimica acta》1976,40(9):1069-1071

A sample of lunar fines collected at a maximum distance, 6.5 km, from the descent engine on Apollo 17 has been analyzed for total amino acids obtainable by hydrolysis of aqueous extracts. The minimum amounts of amino acids, calculated for a disc of 6 km radius are 10⁴–10⁵ times those which could be contributed by the lunar module jet exhaust, on the basis of conservatively limiting assumptions. The amino acids thus obtained are not explainable as due to chemical or biological contamination; their source is accordingly inferred as lunar. Under the conditions of hydrolysis of lunar extracts, cyanide is found to be converted, almost exclusively to glycine, to an extent of 10^?4.  相似文献