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We previously described the genomic structure of the cytochrome P450 1A (CYP1A) gene from the hermaphroditic fish Rivulus marmoratus [Kim, I.-C., Kim, Y.J., Yoon, Y.-D, Kawamura, S., Lee, Y.-S., Lee, J.-S., 2004a. Cloning of cytochrome P450 1A (CYP1A) genes from the hermaphroditic fish Rivulus marmoratus and the Japanese medaka Oryzias latipes. Mar. Environ. Res. 58, 125–129]. To further characterize R. marmoratus CYP1A, we cloned the cDNA sequence of a CYP1A gene from this species and also expressed its recombinant protein in an E. coli system. We exposed R. marmoratus to 4-nonylphenol, and found a small induction of CYP1A mRNA in the treated animals. In this paper, we discuss the characteristics of R. marmoratus CYP1A gene as well as its potential use in a biomonitoring assay. 相似文献
44.
Using density functional simulations, within the generalized gradient approximation and projector-augmented wave method, we study structures and energetics of CaSiO3 perovskite in the pressure range of the Earths lower mantle (0–150 GPa). At zero Kelvin temperature the cubic
CaSiO3 perovskite structure is unstable in the whole pressure range, at low pressures the orthorhombic (Pnam) structure is preferred. At 14.2 GPa there is a phase transition to the tetragonal (I4/mcm) phase. The CaIrO3-type structure is not stable for CaSiO3. Our results also rule out the possibility of decomposition into oxides.
相似文献
Daniel Y. JungEmail: Phone: +41-44-6323744Fax: +41-44-6321133 |
45.
The common practice of freezing sediment cores for later chemical investigation was shown to be inappropriate for samples containing selenium. Pore waters from frozen estuarine sediment cores contained up to eighty times the selenium content of those extracted from chilled but unfrozen cores. Experiments suggested that the increase in selenium concentrations resulted from rupturing the cells of selenium-accumulating bacteria present in the samples. 相似文献
46.
Kocatepe Ayberk Ulak Mehmet Baran Kakareko Grzegorz Ozguven Eren Erman Jung Sungmoon Arghandeh Reza 《Natural Hazards》2019,95(3):615-635
Natural Hazards - Roadway closures magnify the adverse effects of disasters on people since any type of such disruption increases the emergency response travel time (ERTT), which is of central... 相似文献
47.
Zusammenfassung Es wird eine quantitative Ableitung der Coriolisbeschleunigung auf einer rotierenden Kugel gegeben. Die Rechnungen setzen etwa die Kenntnisse eines Abiturienten voraus und sind so geführt, daß die Coriolisbeschleunigung rein in Erscheinung tritt. Erdabplattung und horizontale Führungskräfte, die mit dem Wesen der Corioliskraft nichts zu tun haben, kommen in der Ableitung nicht vor.
An introductory mathematical treatment of the Coriolis force
Summary A quantitative derivation of the Coriolis acceleration on a rotating sphere is given which is considered adequate for students who have passed the final examination of a German High School. Computations are presented in a way that demonstrates the Coriolis acceleration without distracting side issues. The earth's oblateness and the horizontal guiding forces not essentially relating to the Coriolis force are not taken into account in this derivation.
Une introduction dans l'étude de la force de Coriolis
Résumé On donne une dérivation quantitative de l'accélération de Coriolis sur un globe rotatoire. Les calculations nécessaires sont adaptées au savoir d'un bachelier et sont présentées d'une manière que l'accélération de Coriolis est démontrée sans digressions. L'aplatissement de la terre aux pôles et les forces guidantes horizontales qui n'ont pas de rapport essentiel à la nature de l'accélération de Coriolis sont laissés de côté dans cette déduction.相似文献
48.
Evaluation of Hydraulic Properties of Aquitards Using Earthquake‐Triggered Groundwater Variation 下载免费PDF全文
Shih‐Jung Wang Kuo‐Chin Hsu Chein‐Lee Wang Wen‐Chi Lai Liang‐Tzu Hsu 《Ground water》2017,55(5):747-756
The hydraulic properties of aquitards are not easily obtained because monitoring wells are usually installed in aquifers for groundwater resources management. Earthquake‐induced crust stress (strain) triggers groundwater level variations over a short period of time in a large area. These groundwater anomalies can be used to investigate aquifer systems. This study uses a poroelastic model to fit the postseismic variations of groundwater level triggered by the Chi‐Chi earthquake to evaluate the hydraulic properties of aquitards in the Jhoushuei River alluvial fan (JRAF), Taiwan. Six of the adopted eight wells with depths of 70 to 130 m showed good agreement with the recovery theory. The mean hydraulic conductivities (K) of the aquifers for the eight wells are 1.62 × 10?4 to 9.06 × 10?4 m/s, and the thicknesses are 18.8 to 46.1 m. The thicknesses of the aquitards are 11.3 to 42.0 m. Under the isotropic assumption for K, the estimated values of K for the aquitards are 3.0 × 10?8 to 2.1 × 10?6 m/s, corresponding to a silty medium. The results match the values obtained for the geological material of the drilling core and those reported in previous studies. The estimated values were combined with those given in previous studies to determine the distribution of K in the first two aquitards in the JRAF. The distribution patterns of the aquitards reflect the sedimentary environments and fit the geological material. The proposed technique can be used to evaluate the K value of aquitards using inverse methods. The inversion results can be used in hydrogeological analyses, contaminant modeling, and subsidence evaluation. 相似文献
49.
Myung Jin Nam Hee Joon Kim Yoonho Song † Tae Jong Lee Jung Hee Suh 《Geophysical Journal International》2008,174(2):464-474
Topographic effects due to irregular surface terrain may prevent accurate interpretation of magnetotelluric (MT) data. Three-dimensional (3-D) topographic effects have been investigated for a trapezoidal hill model using an edge finite-element method. The 3-D topography generates significant MT anomalies, and has both galvanic and inductive effects in any polarization. This paper presents two different correction algorithms, which are applied to the impedance tensor and to both electric and magnetic fields, respectively, to reduce topographic effects on MT data. The correction procedures using a homogeneous background resistivity derived from a simple averaging method effectively decrease distortions caused by surface topography, and improve the quality of subsurface interpretation. Nonlinear least-squares inversion of topography-corrected data successfully recovers most of structures including a conductive or resistive dyke. 相似文献
50.
A comparison of growth patterns between non‐indigenous Halophila nipponica and the native sympatric Zostera marina on the southern coast of the Korean peninsula 下载免费PDF全文
The growth dynamics of two co‐occurring seagrass species, Zostera marina and Halophila nipponica, were examined on the southern coast of the Korean peninsula. Zostera marina is a native dominant seagrass species in Korean coastal waters, whereas H. nipponica is a non‐native tropical and subtropical species that has extended its distributional range to the temperate coastal areas of Korea. To examine the differences in the growth dynamics of H. nipponica and Z. marina, their morphology, density, productivity and biomass, as well as local environmental conditions, were monitored monthly from January 2008 to July 2009. Underwater irradiance at the study site was the highest in April 2009 and the lowest in January 2008. Water temperature ranged from 10.4°C in January 2009 to 24.8°C in September 2008. Significant differences in growth dynamics were observed between the species, due to the effect of water temperature at the study site. Density and areal productivity were the highest in April 2008 and June 2008, respectively, for Z. marina but the highest in July 2008 for H. nipponica. Leaf size, shoot height and shoot weight were the highest in July 2008 for Z. marina but the highest in August 2008 or September 2008 for H. nipponica. The productivity of both species was strongly correlated with water temperature at the study site. However, the productivity of these species was not strongly correlated with underwater irradiance or the nutrient availability of either the water column or sediment pore water. Zostera marina exhibited the ecological characteristics of a temperate seagrass, whereas H. nipponica retained the features of a subtropical/tropical seagrass, even after adapting to the temperate coastal waters of Korea. 相似文献