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Shanghai, China

Shanghai Ocean University is a public university in Shanghai, China.The university changed its name to the current name on 6 May 2008, authorized by the Ministry of Education The People's Republic of China, and the whole school was to be moved to Lingang New City in August 2008. Its former name is Shanghai Fisheries University . Wikipedia.

Betancur R.,George Washington University | Li C.,Shanghai Ocean University | Munroe T.A.,Smithsonian Institution | Ballesteros J.A.,George Washington University | Orti G.,George Washington University
Systematic Biology | Year: 2013

Non-homogeneous processes and, in particular, base compositional non-stationarity have long been recognized as a critical source of systematic error. But only a small fraction of current molecular systematic studies methodically examine and effectively account for the potentially confounding effect of non-stationarity. The problem is especially overlooked in multi-locus or phylogenomic scale analyses, in part because no efficient tools exist to accommodate base composition heterogeneity in large data sets. We present a detailed analysis of a data set with 20 genes and 214 taxa to study the phylogeny of flatfishes (Pleuronectiformes) and their position among percomorphs. Most genes vary significantly in base composition among taxa and fail to resolve flatfish monophyly and other emblematic groups, suggesting that non-stationarity may be causing systematic error. We show a strong association between base compositional bias and topological discordance among individual gene partitions and their inferred trees. Phylogenetic methods applying non-homogeneous models to accommodate non-stationarity have relatively minor effect to reduce gene tree discordance, suggesting that available computer programs applying these methods do not scale up efficiently to the data set of modest size analysed in this study. By comparing phylogenetic trees obtained with species tree (STAR) and concatenation approaches, we show that gene tree discordance in our data set is most likely due to base compositional biases than to incomplete lineage sorting. Multi-locus analyses suggest that the combined phylogenetic signal from all loci in a concatenated data set overcomes systematic biases induced by non-stationarity at each partition. Finally, relationships among flatfishes and their relatives are discussed in the light of these results. We find support for the monophyly of flatfishes and confirm findings from previous molecular phylogenetic studies suggesting their close affinity with several carangimorph groups (i.e., jack and allies, barracuda, archerfish, billfish and swordfish, threadfin, moonfish, beach salmon, and snook and barramundi). [Base compositional bias; Carangimorphariae; compositional attraction; concatenation; gene tree-species tree; multi-locus data set; non-homogeneous models; non-stationarity; Pleuronectiformes; systematic error.] © 2013 The Author(s). All rights reserved.

Zhang J.,Shanghai Ocean University
Molecular Ecology Resources | Year: 2010

With the development of the DNA barcoding project, a large number of specimens are required to establish the library of reference barcode. Formalin-fixed samples from museums provide a potential resource for it. However, recovery of DNA and amplification of the target gene from formalin-fixed samples are challenging. In this study, a hot alkali pre-treatment accompanied by the use of cetyltrimethylammonium bromide (CTAB) method was employed for DNA recovery from formalin-preserved samples, with the purpose of pursuing the optimal condition for high quantity and quality of DNA and minimizing PCR inhibition. Meanwhile, a semi-nested PCR-based method was developed to enhance the efficacy of amplification. This advanced protocol was demonstrated to be reliable and effective. Even for 23-year-old samples, genomic DNA could be extracted, and COI gene was correctly sequenced. © 2010 Blackwell Publishing Ltd.

Liew K.M.,City University of Hong Kong | Lei Z.X.,City University of Hong Kong | Lei Z.X.,University of Science and Technology of China | Yu J.L.,University of Science and Technology of China | Zhang L.W.,Shanghai Ocean University
Computer Methods in Applied Mechanics and Engineering | Year: 2014

This paper presents a postbuckling analysis of carbon nanotube-reinforced functionally graded (CNTR-FG) cylindrical panels under axial compression. Based on kernel particle approximations for the field variables, the Ritz method is employed to obtain the discretized governing equations. The cylindrical panels are reinforced by single-walled carbon nanotubes (SWCNTs) which are assumed to be graded through the thickness direction with different types of distributions. The effective material properties of CNTR-FG cylindrical panels are estimated through a micromechanical model based on the extended rule of mixture. To eliminate shear locking for a very thin cylindrical panel, the system's bending stiffness is evaluated by a stabilized conforming nodal integration scheme and the membrane as well as shear terms are calculated by the direct nodal integration method. In the present study, the arc-length method combined with the modified Newton-Raphson method is used to trace the postbuckling path. Detailed parametric studies are carried out to investigate effects of various parameters on postbuckling behaviors of CNTR-FG cylindrical panels and results for uniformly distributed (UD) CNTR-FG cylindrical panel are provided for comparison. © 2013 Elsevier B.V.

Zhang L.W.,Shanghai Ocean University | Zhu P.,Hunan University | Liew K.M.,City University of Hong Kong
Composite Structures | Year: 2014

The mechanical and thermal buckling behaviors of ceramic-metal functionally grade plates (FGPs) were studied by using a local Kriging meshless method. The local meshless method was developed based on the local Petrov-Galerkin weak-form formulation combined with shape functions having the Kronecker delta function property, constructed by the Kriging interpolation. The cubic spline function of high continuity was used as the weight function to simplify the local weak form of governing equations with the integration on the internal boundaries vanishing. The transverse shear strains of FGPs were incorporated by employing the first-order shear deformation plate theory and plate material properties were assumed to change exponentially along the thickness direction. Convergence and comparison studies examined the stability and accuracy of the presented method. Two types of FGMs, Al/Al2O3 and Ti-6Al-4V/Aluminum oxide, were chosen for mechanical and thermal buckling analyses. The influences of volume fraction exponent, boundary condition, length-to-thickness ratio and loading type on the buckling behaviors of FGPs were discussed. © 2013 Elsevier Ltd.

Luo J.,Shanghai Ocean University
Mathematical Biosciences | Year: 2013

In this paper, we derive and analyze a mathematical model for the interactions between phytoplankton and zooplankton in a periodic environment, in which the growth rate and the intrinsic carrying-capacity of phytoplankton are changing with respect to time and nutrient concentration. A threshold value: "Predator's average growth rate" is introduced and it is proved that the phytoplankton-zooplankton ecosystem is permanent (both populations survive cronically) and possesses a periodic solution if and only if the value is positive. We use TP (Total Phosphorus) concentration to mark the degree of eutrophication. Based on experimental data, we fit the growth rate function and the environmental carrying capacity function with temperature and nutrient concentration as independent variables. Using measured data of temperature on water bodies we fit a periodic temperature function of time, and this leads the growth rate and intrinsic carrying-capacity of phytoplankton to be periodic functions of time. Thus we establish a periodic system with TP concentration as parameter. The simulation results reveal a high diversity of population levels of the ecosystem that are mainly sensitive to TP concentration and the death-rate of zooplankton. It illustrates that the eruption of algal bloom is mainly resulted from the increasing of nutrient concentration while zooplankton only plays a role to alleviate the scale of algal bloom, which might be used to explain the mechanism of algal bloom occurrence in many natural waters. What is more, our results provide a better understanding of the traditional manipulation method. © 2013 Elsevier Inc.

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