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Genetic transformation is gaining importance for developing plant types suitable to metal accumulate and/or hyperaccumulate. In this study, the transgenic tobacco plant which transferred the ScMTII gene from Saccharomyces cerevisiae to wild type tobacco cultivar Petite Havana (SR1) was grown on soils with low and high cadmium (Cd) and zinc (Zn) concentrations in a growth chamber for 6 weeks and compared to wild type tobacco for Cd and Zn accumulation. Cadmium and Zn accumulations in the transgenic and wild type tobacco plants were increased with the increasing Cd and Zn concentrations. Unlike Zn, the transgenic plant accumulated significantly higher amount of Cd compared to the wild type control plants. Shoot Cd concentrations of transgenic tobacco in higher Cd dosages reached the above the hyperaccumulation threshold value of 100 mg Cd kg?1 in the dry weight (DW). Transgenic tobacco accumulated 354, 400, 372, and 457 mg Cd kg?1 DW, for 10, 20, 40, and 80 mg Cd kg?1 soil treatments, respectively. These values are 3.5–4.5‐fold higher than that of Cd hyperaccumulation threshold value. With 10 mg kg?1 Cd treatment, the bioconcentration factor (BCF) of transgenic tobacco plants for Cd reached up to 35 in which the threshold value for BCF should be at least 10. Our results showed that the transgenic tobacco may be used as a good Cd hyperaccumulator plant and for phytoextraction of Cd contaminated soils, but not for Zn.  相似文献   
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In this paper, regionalP-wave upper mantle structure is investigated using slant-stack velocity analysis of short-period earthquake data recorded at station MAJO (Matsushiro, Japan). Shallow earthquakes from 1980–1986 within 35° of MAJO are used to construct a common receiver gather. Processing of the wavefield data includes focal depth and static time corrections, as well as deterministic deconvolution, in order to equalize pulse shapes and align wavelets on the first arrivals. The processed wavefield data are slant stacked and interatively downward continued to obtain a regional upper mantle velocity model. The model includes a low velocity zone between 107 and 220 km. Beneath the LVZ, the velocity increases smoothly down to the discontinuity at 401 km. In the transition zone, the velocity model again increases linearly, although there is some suggestion of further complexity in the downward continued wavefield data. At the base of the transition zone, a second velocity discontinuity occurs at 660 km, with a linear velocity gradient below. In addition to slant-stack analysis, travel times and synthetic seismograms are computed and compared with the processed and unprocessed wavefield data.  相似文献   
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Tsunami mitigation, preparedness and early warning initiatives have begun at the global scale only after the tragic event of Sumatra in 2004. Turkey, as a country with a history of devastating earthquakes, has been also affected by tsunamis in its past. In this paper we present the Tsunami Hazard in the Eastern Mediterranean and its connected seas (Aegean, Marmara and Black Sea) by providing detailed information on historically and instrumentally recorded significant tsunamigenic events surrounding Turkey, aiming to a better understanding of the Tsunami threat to the Turkish coasts. In addition to the review of the Tsunami hazard, we have studied a possible Tsunami source area between Rhodes and SW of Turkey using Tsunami numerical model NAMI DANCE-two nested domains. We have computed a maximum positive amplitude of 1.13 m and maximum negative amplitude of −0.5 m at the Tsunami source by this study. The distribution of maximum positive amplitudes of the water surface elevations in the selected Tsunami forecast area and time histories of water level fluctuations near selected locations (Marmaris, Dalaman, Fethiye and Kas towns) indicate that the maximum positive amplitude near the coast in the selected forecast area exceeds 3.5 m. The arrival time of maximum wave to Marmaris, Dalaman, is 10 min, while that of Fethiye and Kas towns is 15–20 min. The maximum positive amplitudes near the shallow region of around 10 m depth are 3 m (Marmaris), 1 m (Dalaman), 2 m (Fethiye) and 1 m (Kas). Maximum positive amplitudes of water elevations in the duration of 4 h simulation of the Santorini-Minoan Tsunami in around 1600 BC in the Aegean Sea are also calculated based on a simulation performed using 900 m grid resolution of Aegean sea bathymetry with a 300 m collapse of 10 km diameter of Thera (Santorini) caldera. We have also presented the results of the Tsunami modeling and simulation for Marmara Sea obtained from a previous study. Last part of this paper provides information on the establishment of a Tsunami Warning Center by KOERI, which is expected to act also as a regional center under the UNESCO Intergovernmental Oceanographic Commission – Intergovernmental Coordination Group for the Tsunami Early Warning and Mitigation System in the North-Eastern Atlantic, the Mediterranean and Connected Seas (ICG/NEAMTWS) initiative, emphasizing on the challenges together with the future work needed to be accomplished.  相似文献   
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Calc-alkaline rocks of the Hasan Dagi volcano (Central Anatolia, Turkey) are products of arc volcanism triggered by continental collision. Volcanic rocks of the Hasan Dagi range in composition from basalt to rhyolite but are dominated by andesite and dacite. Considering only the mass transfer part of the process leads to an incomplete picture of magma chamber processes. The exclusion of simultaneous calculations of heat and mass transfer between mixing magmas, however, has prevented petrologists from gaining new insights into the magma mixing process. Thus, we report our experimental results in conjunction with modeling with MELTS to test the ideas concerning the petrogenesis of Hasan Dagi volcanic rocks and quantitatively model the relevant petrogenetic processes. Our results demonstrate that the chemical diversity of Hasan Dagi volcano is inconsistent with the closed-system crystallization and differentiation. Thus, (1) our experimental modeling, (2) the agreement between the liquid line of descent defined by the natural rock data and the MELTS calculations, and (3) the agreement between the mineralogy of the rocks and calculated mineralogy corroborate the conclusion that the isobaric–isenthalpic magma mixing of basalt and rhyolite is the major controlling process in the petrogenesis of the Hasan Dagi magmas.  相似文献   
7.
In this study, unlike backpropagation algorithm which gets local best solutions, the usefulness of particle swarm optimization (PSO) algorithm, a population-based optimization technique with a global search feature, inspired by the behavior of bird flocks, in determination of parameters of support vector machines (SVM) and adaptive network-based fuzzy inference system (ANFIS) methods was investigated. For this purpose, the performances of hybrid PSO-ε support vector regression (PSO-εSVR) and PSO-ANFIS models were studied to estimate water level change of Lake Beysehir in Turkey. The change in water level was also estimated using generalized regression neural network (GRNN) method, an iterative training procedure. Root mean square error (RMSE), mean absolute error (MAE), and coefficient of determination (R 2) were used to compare the obtained results. Efforts were made to estimate water level change (L) using different input combinations of monthly inflow-lost flow (I), precipitation (P), evaporation (E), and outflow (O). According to the obtained results, the other methods except PSO-ANN generally showed significantly similar performances to each other. PSO-εSVR method with the values of minMAE = 0.0052 m, maxMAE = 0.04 m, and medianMAE = 0.0198 m; minRMSE = 0.0070 m, maxRMSE = 0.0518 m, and medianRMSE = 0.0241 m; minR 2 = 0.9169, maxR 2 = 0.9995, medianR 2 = 0.9909 for the I-P-E-O combination in testing period became superior in forecasting water level change of Lake Beysehir than the other methods. PSO-ANN models were the least successful models in all combinations.  相似文献   
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We analyze the waveforms generated by the January 12, 2010 Haiti earthquake (Mw=7.0) for its source characteristics. A 60 to 25 km source model is retrieved by the Kikuchi and Kanamori finite source inversion technique that uses broadband teleseismic body wave records. The derived rupture model points out unilateral rupture propagation commenced at the eastern side of the fault plane where the major seismic moment release occurred. The rupture front propagated westward and terminated at a site where the largest aftershocks occurred. Our estimates yield a seismic moment of Mo=8.17×1019 N m released on a 60 km-long fault plane. A patch at the eastern side of the ruptured fault plane inferred as a region of maximum moment release.  相似文献   
10.
The Maastrichtian regressive sequence of the Hekimhan-Malatya area in Eastern Turkey consists of dolomitic limestones, limestones and calcareous mudstones which are dominated by rudists and Loftusia (foraminifera) assemblages. Several Loftusia species indicating middle to late Maastrichtian age such as Loftusia anatolica Meriç, L. baykali Meriç, L. coxi Henson, L. harrisoni Cox, L. minor Cox and L. morgani Douvillé have been recorded. Other benthic foraminifers present include Orbitoides medius d’ Archiac, Omphalocyclus macroporus (Lamarck), Laffitteina conica Drooger, Laffitteina mengaudi (Astre) and Laffitteina oeztuerki Inan. The rudists are abundant in the dolomitic limestones in the study area. The genus Miseia Patrulius is dominant and represented by Miseia bilacunosa Özer and Miseia hekimhanensis Karacabey-Öztemür. The Loftusia species and the Rudists assemblage indicates middle to late Maastrichtian age for the formation. The paleobiogeographic distribution of the assemblage has been discussed taking this find into account.  相似文献   
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