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The genus Symbiodinium plays an essential role in the resistance and survival of reef‐building corals during temperature anomalies. Coral colonies inhabiting the Persian Gulf (PG) experience extended periods of different stresses. Kish Island is located in the harsh environment of the Northern PG with previously reported bleaching episodes. Samples of six coral species from Northwestern Kish Island were analysed by internal transcribed spacer 2 of ribosomal DNA to identify in hospite Symbiodinium populations. The results showed that lineage D of Symbiodinium was the most prevalent clade among different coral colonies, while clade C was only detected in symbiosis with a single coral species. However, the detected Symbiodinium subclades belonged to two host generalists. The predominance of the stress tolerant Symbiodinium trenchii and subclade C3 could suggest an acclimatization strategy to cope with the hostile environment of the PG.  相似文献   
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This paper proposes a new Free-Lagrange method based on the kinetic Voronoi diagram for fluid simulation. The objective here is to combine the advantages of an adoptive mesh structure with the advantages of kinetic mesh maintenance, and demonstrate their value for dynamic simulation. Despite the theoretical advantages of the Free-Lagrange method, its use has been handicapped with the reconstruction of topology after each time step that considerably reduces the efficiency of the method. In addition, the use of fixed time steps causes problems such as overshoots and undetected collisions. In order to demonstrate the ability of the proposed model to solve these problems, the method is applied to a dam-breaking problem and global tides. With the results obtained from these numerical experiments, the validity of the global kinetic data structure is approved. In particular, the method is found to be more efficient than existing methods. In addition, qualitative comparison of physical results with analytical solutions demonstrates the similarity of the results and confirms the physical validity of the proposed method. Further investigations with real-world data and the complete equation of motion are suggested to compare it with other numerical methods.  相似文献   
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This paper describes the application of the knowledge-based fuzzy logic method to integrate various exploratory geo-dataset in order to prepare a mineral prospectivity map (MPM) for copper exploration. Different geophysical layers which are derived from the magnetic and the electrical surveys, along with the ones extracted from the background geology (i.e., lithology, fault and alteration) and geochemical data are incorporated in such process. Seridune copper deposit located in the Kerman province of Iran is the case study to delineate its high potential zones of Cu-bearing mineralization for drilling additional boreholes. Four layers from the magnetic data involving upward continuation, analytic signal, reduced to pole and pseudo gravity are assigned in the multi-disciplinary geo-dataset to locate the intrusive complexes responsible for Cu mineralization. The apparent resistivity, chargeability and sulfide factor layers acquired from geo-electrical data are also included in the final preparation of MPM. Then the normalized weights of seven geophysical, three geological and one geochemical evidential layers as main criteria are determined based upon the knowledge of expert decision makers. Fuzzy operators (i.e., Sum and Gamma) are applied to integrate these exploratory features. To evaluate the performance and applicability of the approach, the productivity of the drilled boreholes (Cu concentration multiplied by ore thickness) are used to validate the produced MPMs. It is shown that an optimum correlation coefficient of 0.86 exists between the MPM values and Cu productivity criterion along drilled boreholes.  相似文献   
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This research is to study the efficiency of displacement reducer fuses, installed behind the caisson quay walls for controlling the dynamic backfill thrust and minimizing the displacement, settlement and tilting of the walls. For this purpose, two types of fuses, Displacement Reducer Panels (DRP) and Displacement Reducer Elements (DRE), were constructed and installed behind the wall. The DRPs were constructed by hollow Polypropylene sheets to reproduce elastoplastic and plastic mechanical behaviors. The DREs were cylindrical stainless-steel dampers, working upon friction mechanism that can reproduce perfect plastic behavior. Here, two series of shaking table 1-g tests were performed with DRP and DRE applications. In this regard, different mechanical behaviors and capacities were considered for fuses against demand thrusts of backfill in order to compare the mitigation tests with no-mitigation cases. Harmonic base motions with constant amplitude and constant frequency were used in the model test. The foundation soil and the backfill soil were constructed with the relative densities of 85 and 25%, respectively, to reproduce non-liquefiable base layer and loose backfill situations in the model, respectively. The results showed remarkable reduction in kinetic energy, dynamic backfill thrust and consequently seaward movement, settlement and inclination of the caisson quay wall in case of using fuses with plastic behaviors behind the wall.  相似文献   
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