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31.
Nassef M Tawaratsumita T Oba Y Satone H Nakayama K Shimasaki Y Honjo T Oshima Y 《Marine pollution bulletin》2011,62(2):412-414
In this study, individual Japanese flounder were intraperitoneally injected with 2 μg tributyltin-d27 (TBT-d27) fish−1. Blood samples were collected on day 7 after injection. TBT-binding protein types 1 and 2 (TBT-bp1, -bp2) in the blood serum were quantified by western blotting analysis. As a result, the concentration of TBT-bp2 in TBT-d27 treated group increased to 220% of that in the solvent control, whereas the TBT-bp1 concentration decreased to 65% of that in the solvent control. Additionally, a positive relationship between the concentrations of TBT-bp2 and TBT was observed in blood sera of wild and cultured flounder. We suggest that TBT-bp2 is produced in response to TBT exposure and may play an important role in fish physiology. 相似文献
32.
We used an in situ measurement method to investigate the phase transition of CaGeO3 polymorphs under high pressures and temperatures. A multi-anvil high-pressure apparatus combined with intense synchrotron
X-ray radiation was used. The transition boundary between a garnet and a perovskite phase at T = 900–1,650 K and P = 3–8 GPa was determined as occurring at P (GPa) = 9.0−0.0023 × T (K). The transition pressure determined in our study is in general agreement with that observed in previous high-pressure
experiments. The slope, dP/dT, of the transition determined in our study is consistent with that calculated from calorimetry data. 相似文献
33.
Dynamic spectra of S-bursts of Jovian decametric radiations are obtained by using a high time resolution radio spectrograph
which has a time resolutionof 2 msec and the bandwidth of 2 MHz.Within occurrence of 65 S-burst events observed in the period
from 1983 to 1999, 26 events have been identified as the S-N burst events, which are characterized by the interaction between
the S-burst emissions and the Narrow band emissions. In the dynamic spectra of the S-N burst, the trend of emissions with
negative and slower frequency drift named as “Trailing Edge Emission” are often observed shortly after the appearance of the
S-burst.Detailed analyses of these phenomena revealed that the Trailing Edge Emission is not a manifestation of S-burst with
slower drift rate but a variation ofN-burst. The results suggested that S-burst and the associated Trailing Edge Emission
are formed simultaneously started from a common region with different drift rates. It has been further suggested that the
appearance of the S-burstsis not controlled by the geometrical effect between the source region and theobserver, but directly
reflects the generation of the source region widelydistributed in an altitude range from a few thousands km to 30,000 km,
alongthe Io flux tube.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
34.
乐佩琦 《中国海洋湖沼学报》1995,(3)
Adult pharyngeal teeth in Mylopharyngodon piceus are molariform. Based on SEM observations ofthe developing teeth, this paper describes the morphological diversification of pharyngeal teeth in M.piceus. The larval and juvenile teeth are changed from conical to adult molariform teeth through sevenstages. Comparisons are made between each stage and corresponding types in some species of differentsubfamilies in Cyprinidae. It is considered that the ontogenetic resemblances of the pharyngeal teehbear relationship to the phylogeny of cyprinids. 相似文献
35.
Takenobu Michioka Hiroshi Takimoto Hiroki Ono Ayumu Sato 《Boundary-Layer Meteorology》2018,168(2):247-267
The effects of fetch on turbulent flow and pollutant dispersion within a canopy formed by regularly-spaced cubical objects is investigated using large-eddy simulation. Six tracer gases are simultaneously released from a ground-level continuous pollutant line source placed parallel to the spanwise axis at the first, second, third, fifth, seventh and tenth rows. Beyond the seventh row, the standard deviations of the fluctuations in the velocity components and the Reynolds shear stresses reach nearly equivalent states. Low-frequency turbulent flow is generated near the bottom surface around the first row and develops as the fetch increases. The turbulent flow eventually passes through the canopy at a near-constant interval. The mean concentration within the canopy reaches a near-constant value beyond the seventh row. In the first and second rows, narrow coherent structures frequently affect the pollutant escape from the top of the canopy. These structures increase in width as the fetch increases, and they mainly affect the removal of pollutants from the canopy. 相似文献
36.
The depositional environments and bivalve assemblages are determined for the Upper Cretaceous Hinoshima Formation of the Himenoura Group, Kamishima, Amakusa Islands, Kyushu, Japan. The Hinoshima Formation is characterized by a thick transgressive succession that varies from incised-valley-fill deposits to submarine slope deposits with high aggradation rates of depositional systems. The incised valley is filled with fluvial, bayhead delta, brackish-water estuary, and marine embayment deposits, and is overlain by thick slope deposits.Shallow marine bivalves are grouped into five fossil assemblages according to species composition: Glycymeris amakusensis (foreset beds of a bayhead delta), Nippononectes tamurai (foreset beds of a bayhead delta), Ezonuculana mactraeformis–Nucula formosa (central bay), Glycymeris amakusensis–Apiotrigonia minor (slope), and Inoceramus higoensis–Parvamussium yubarensis (slope). These bivalve assemblages all represent autochthonous and parautochthonous conditions except for a Glycymeris amakusensis–Apiotrigonia minor assemblage found in debris flow and slump deposits. The life habitats of these bivalves and the compositions of the assemblages are discussed in terms of the ecological history of fossil bivalves of the mid- to Late Cretaceous. 相似文献
37.
A three-dimensional seismometer array was installed in the Chiba Experiment Station of the Institute of Industrial Science, University of Tokyo in 1982. The array system consists of 44 three-component accelerometers densely placed both on the ground surface and in boreholes. A complementary system for the measurement of ground and buried pipe strains was also installed at the same site. The array system has been successfully in operation, and more than 160 earthquakes have been recorded. Considering a wide use of these seismograms, the Chiba array database has recently been created comprising twenty-seven major events. This paper describes the Chiba array system and its strong motion database. Results of engineering analysis using the selected records are also presented. 相似文献
38.
Intense rainfall on July 12, 2012, triggered numerous shallow landslides on steep grassy hillslopes of Aso Volcano, Kyushu, Japan. The hillslopes are mantled by several meters thickness of fallout tephra accumulation from Holocene eruptions. The landslides occurred about 1 m deep in surficial tephra deposits. Stratigraphic surveys of three landslides showed that the tephra deposits beneath the ground consist of two layers, an upper blackish and a lower yellow-brown layer, and that the upper layer represents the accumulation of tephra during the last 1000 years. The surveys also demonstrated that the slip surfaces were formed near the boundary of the two layers, resulting in the sliding of the upper layer. We measured the saturated hydraulic conductivities of both the layers. The hydraulic conductivities of the lower layer are 1 to 2 orders of magnitude lower than those of the upper layer, suggesting that the lower layer acts as an aquiclude. Therefore, pore water pressure locally increases near the boundary between the two layers and failure occurs. We also examined the soil hardness, which has a high correlation with soil shear strength parameters, of the tephra layers at the three landslides. The soil hardness of the lower layer is greater than that of the upper layer in two of the landslides, suggesting that the lower layer collapses less readily than the upper layer. Comparison with previous landslides in the study area demonstrates that this type of rainfall-induced landslide event has occurred in the past and will recur in the future. 相似文献
39.
40.
Phytoplankton distribution and its relationship to water masses were investigated in the East China Sea from February 15 to March 10, 1993. Diatoms, dinoflagellates and coccolithophorids were examined by the Utermöhl method. Two distinct phytoplankton assemblages were identified: a shelf and oceanic assemblage. The shelf community was characterized by a high abundance of diatoms, particularly, a benthic diatomParalia sulcata, and the oceanic community by numerical dominance of coccolithophorids and occurrence of surface warm-water species of diatoms. A boundary of both communities was located at the shelf edge that coincided with the shelf side of a Kuroshio front.P. sulcata was the most dominant in the inner shelf area throughout the water column. The occurrence of this species near the surface was considered to be a good indicator of the enhanced vertical mixing driven by winter monsoon. The species survives under extremely low light intensity near the bottom during the stratified periods in summer. During the winter time when light condition at the bottom becomes most unfavorable, resuspension and upward traveling of the species due to enhanced vertical mixing seem to be advantageous to acquire suitable light condition. Because of its predominance, possible importance ofP. sulcata is suggested in material cycling on the shelf, particularly near the bottom. 相似文献