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Qingdao, China

The Ocean University of China , colloquially known as Haida is a university in Qingdao. As one of the key comprehensive universities of China, it is under the direct jurisdiction of the Ministry of Education. While offering studies in all major branches of technical and social science, the university is especially renowned for its marine science and fishery science departments. Wikipedia.

Jing J.,Jilin University | Jing J.,University of the Basque Country | Wu L.-A.,University of the Basque Country | Wu L.-A.,Ikerbasque | And 4 more authors.
Physical Review Letters | Year: 2015

Dynamical decoupling operations have been shown to reduce errors in quantum information processing. Leakage from an encoded subspace to the rest of the system space is a particularly serious problem for which leakage elimination operators (LEOs) were introduced. Here we provide an analysis of nonideal pulses, rather than the well-understood idealization or bang-bang controls. Under realistic conditions, we show that these controls will provide the same protection from errors as idealized controls. Our work indicates that the effectiveness of LEOs depends on the integral of the pulse sequence in the time domain, which has been missing because of the idealization of pulse sequences. Our results are applied to a three-level system for the nitrogen-vacancy centers under an external magnetic field and are illustrated by the fidelity dynamics of LEO sequences, ranging from regular rectangular pulses, random pulses, and even disordered (noisy) pulses. © 2015 American Physical Society.

Jiang G.,Ocean University of China
African Journal of Biotechnology | Year: 2012

The transmission of white spot syndrome virus (WSSV) in the aquatic environment by the pathway of phytoplankton through rotifer to artemia and shrimp was investigated. The phytoplankton Alexandrium tamarense and Alexandrium minutum were co-cultured with adult Fenneropenaeus chinensis infected with WSSV and were assayed by whole cell fluorescence in situ hybridization (WFISH) with probe specific for WSSV labeled with 5-carboxyfluoroscein at 5'-end to study whether they could carry WSSV. Then, the WSSV positive phytoplankton was exposed to the rotifer Brachionus urceu and was assayed by dot blot hybridization with digoxigenin labeled DNA probe. Further experiments were conducted to feed artemia Artemia franciscana with the WSSV positive rotifers and feed juvenile shrimps F. chinensis with the artemia. Our results showed that the pytoplankton were WSSV-positive after 24 h incubation. The dot-blot diagnosis revealed WSSV-positive results in the rotifers exposed to WSSV positive phytoplankton. The cumulative mortality of shrimp and dot blot diagnosis showed that the shrimp can be infected by the food chain of phytoplankton→rotifer→artemia→shrimp. © 2012 Academic Journals.

Zhang J.,Nanjing University | Zhang J.,University of South Florida | Lu X.,Ocean University of China
Computer Methods in Applied Mechanics and Engineering | Year: 2010

The four-dimensional variational data assimilation technology based on the theory of inverse problem is applied to simulate the three-dimensional tidal currents in the marginal seas by assimilating the satellite altimetry. The model is calibrated by the twin experiments where the prescribed open boundary conditions for a three-dimensional barotropic tidal model are successfully inverted. By assimilating the tidal harmonic constants derived from TOPEX/Poseidon altimeter data, the open boundary conditions are optimized and the M2 tidal currents in the Bohai and Yellow Seas (BYS) are simulated in the practical experiment. During the assimilation, the cost function and the gradients of cost function with respect to the open boundary conditions have been decreased significantly. Although the current observations are not assimilated into the model, the cost function composed of the data misfit between model-produced and observed currents is still decreased from 1.00 to 0.09, which demonstrates the reasonability and feasibility of inverting tidal currents from satellite altimetry or other elevation measurements. The co-tidal charts and the near-surface M2 tidal current ellipses obtained in the practical experiment are in good agreement with the observed tides and tidal currents in BYS. © 2010 Elsevier B.V.

Liu Y.,Ocean University of China | Li Y.,Dalian University of Technology
Journal of Engineering Mathematics | Year: 2011

This study gives an alternative analytical solution for water-wave motion over an offshore submerged horizontal porous-plate breakwater in the context of linear potential theory. The matched-eigenfunction-expansions method is used to obtain the solution. The solution consists of a symmetric part and an antisymmetric part. The symmetric part is also the solution of wave reflection by a vertical solid wall with a submerged horizontal porous plate attached to it. In comparison with previous analytical solutions with respect to finite submerged horizontal porous plates, no complex water-wave dispersion relations are included in the present solution. Thus, the present solution is easier for numerical implementation. Numerical examples show that the convergence of the present solution is satisfactory. The results of the present solution also agree well with previous results by different analytical approaches, as well as previous numerical results by different boundary-element methods. The present solution can be easily extended to the case of multi-layer submerged horizontal porous plates, which may be more significant in practice for meeting different tide levels. © 2010 Springer Science+Business Media B.V.

Li J.,Qingdao Agricultural University | Tang G.-Y.,Ocean University of China
IET Control Theory and Applications | Year: 2010

This study researches the fault diagnosis approach for networked control systems (NCSs) with delayed measurements and inputs. Different from current fault diagnosis approaches that regard all delays in NCSs as an input delay, this paper presents a new fault diagnosis approach for NCSs that considers delayed measurements and inputs simultaneously and presents a discrete delay-free transformation approach for delayed measurements. By constructing an augmented system that comprises the states of faults and by delay-free transformations of delayed measurements and inputs for the augmented system, the problem of fault diagnosis for NCSs with delayed measurements and inputs is transformed into the problem of state observation of a delay-free augmented system. A new design approach to the fault diagnoser is presented for NCSs by constructing a novel reduced-order state observer of the augmented system, which can real-time diagnose faults without using residual to embody faults. Finally, the feasibility and effectiveness of the proposed approaches are validated by a numerical example. © 2010 The Institution of Engineering and Technology.

Caldelari D.,Duke University | Caldelari D.,University of Lausanne | Wang G.,Duke University | Wang G.,Ocean University of China | And 2 more authors.
Plant Molecular Biology | Year: 2011

Fertility and flower development are both controlled in part by jasmonates, fatty acid-derived mediators produced via the activity of 13-lipoxygenases (13-LOXs). The Arabidopsis thalianaColumbia-0 reference genome is predicted to encode four of these enzymes and it is already known that one of these, LOX2, is dispensable for fertility. In this study, the roles of the other three 13-LOXs (LOX3, LOX4 and LOX6) were investigated in single and double mutants. Four independent lox3 lox4 double mutants assembled with different mutated lox3 and lox4 alleles had fully penetrant floral phenotypes, displaying abnormal anther maturation and defective dehiscence. The plants were no longer self-fertile and pollen was not viable. Fertility in the double mutant was restored genetically by complementation with either the LOX3 or the LOX4 cDNAs and biochemically with exogenous jasmonic acid. Furthermore, deficiency in LOX3 and LOX4 causes developmental dysfunctions, compared to wild type; lox3 lox4 double mutants are taller and develop more inflorescence shoots and flowers. Further analysis revealed that developmental arrest in the lox3 lox4 inflorescence occurs with the production of an abnormal carpelloid flower. This distinguishes lox3 lox4 mutants from the wild type where developmentally typical flower buds are the terminal inflorescence structures observed in both the laboratory and in nature. Our studies of lox3 lox4 as well as other jasmonic acid biosynthesis and perception mutants show that this plant hormone is not only required for male fertility but also involved in global proliferative arrest. © 2010 Springer Science+Business Media B.V.

Zhang L.,University of Miami | Zhang L.,National Oceanic and Atmospheric Administration | Zhang L.,Ocean University of China | Wang C.,National Oceanic and Atmospheric Administration
Geophysical Research Letters | Year: 2012

The understanding of freshwater flux variability is both scientifically and socially important. Local freshwater flux response to a large Atlantic warm pool (AWP) is excessive freshwater or negative Evaporation minus Precipitation (EmP) anomalies, whereas the response is deficient to a small AWP. However, the EmP anomalies in the AWP region are also influenced by the SST anomalies in the tropical eastern Pacific and in the tropical South Atlantic. These remote influences operate through the inter-basin mode represented by the SST gradient between the tropical North Atlantic and eastern Pacific and the Atlantic meridional mode (AMM) defined as the SST gradient between the tropical North and South Atlantic. When either of these two modes is in the negative phase, the EmP and sea surface salinity anomalies in the AWP region can be positive although the AWP is large. This indicates that the remote influences of the inter-basin mode and/or the AMM can overwhelm the local effect and induce an opposite freshwater response. Additionally, although ENSO and the AMM sometimes coincide with AWP variability, an El Nio in the preceding winter or a positive AMM in the spring does not necessarily follow a large AWP in the summer. © 2012. American Geophysical Union. All Rights Reserved.

Zhang Z.,Yantai University | Li X.,Yantai University | Zhao Y.,Ocean University of China
Advanced Nonlinear Studies | Year: 2010

Let ω be a bounded domain with smooth boundary in ℝn and h ∈C((0,∞), (0, ∞)) with lims → 0+ h(s) = υ ∈ (0, ∞). By the perturbation method, which is due to García Melian, and nonlinear transformations and comparison principles, we derive the exact boundary behavior of solutions to a singular Dirichlet problem -δv +h(v)/v|∇v|2 = b(x), v > 0, x∈ ω, v\δω = 0. Then, applying the result, combining two kinds of nonlinear transformations, we derive the exact boundary behavior of solutions to a boundary blow-up elliptic problem and a singular Dirichlet problem, where the weight b is positive in ω and may be (rapidly) vanishing or blow up on the boundary.

Zhang Y.,Ocean University of China
Polymer Bulletin | Year: 2015

Carbon nanotubes/polyacrylic acid coating materials have been synthesized by in situ precipitation polymerization. The coating structure of functionalized CNTs was characterized by infrared spectrometer, thermogravimetric analyzer, and transmission electron microscopy. The results showed that PAA has coated on the surface of CNTs. The polyacrylic acid-functionalized CNTs could be dispersed in water, then forming stable dispersions. The amount of PAA grafted was dependent on CNTs/monomer ratios. © 2015, Springer-Verlag Berlin Heidelberg.

Zhang J.,Ocean University of China
Transportation Research Part A: Policy and Practice | Year: 2016

Since the 1970s and 80s, landlord port has been the dominant port financing model in western large and medium-sized container ports. In China, many prospective port projects have also explored a landlord port financing model. However, some evidence suggests that landlord port financing in China is a variant of the international mainstream landlord port financing model. Based on an explanation of their unique features and practices, this paper analyzes the Chinese quasi-landlord port financing model from a contract theory perspective, in which it can be viewed as a double-level principal-agent relationship and two-layer profit distribution contract with three participants: the state-owned assets administration department, the port investment company and the operators. Furthermore, the results show that in the Chinese quasi-landlord port financing model, whether in the case of both joint venture and port land lease (fixed rent), or in the case of both joint venture and port land transfer, the optimal incentive scheme is the same as in the international landlord port financing model with profit sharing rent or mixed rent. © 2016 Elsevier Ltd.

The sea cucumber Apostichopus japonicus withstands high water temperatures in the summer by suppressing its metabolic rate and entering a state of aestivation. We hypothesized that changes in the expression of miRNAs could provide important post-transcriptional regulation of gene expression during hypometabolism via control over mRNA translation. The present study analyzed profiles of miRNA expression in the sea cucumber respiratory tree using Solexa deep sequencing technology. We identified 279 sea cucumber miRNAs, including 15 novel miRNAs specific to sea cucumber. Animals sampled during deep aestivation (DA; after at least 15. days of continuous torpor) were compared with animals from a non-aestivation (NA) state (animals that had passed through aestivation and returned to an active state). We identified 30 differentially expressed miRNAs ([RPM (reads per million) >. 10, |FC| (|fold change|). ≥. 1, FDR (false discovery rate). <. 0.01]) during aestivation, which were validated by two other miRNA profiling methods: miRNA microarray and real-time PCR. Among the most prominent miRNA species, miR-124, miR-124-3p, miR-79, miR-9 and miR-2010 were significantly over-expressed during deep aestivation compared with non-aestivation animals, suggesting that these miRNAs may play important roles in metabolic rate suppression during aestivation. High-throughput sequencing data and microarray data have been submitted to the GEO database with accession number: 16902695. © 2014 Elsevier B.V.

Liu F.,CAS Institute of Software | Wu C.,CAS Institute of Software | Lin X.,Ocean University of China
IEEE Transactions on Information Forensics and Security | Year: 2010

Two common drawbacks of the visual cryptography scheme (VCS) are the large pixel expansion of each share image and the small contrast of the recovered secret image. In this paper, we propose a step construction to construct VCSOR and VCSXOR for general access structure by applying (2,2)-VCS recursively, where a participant may receive multiple share images. The proposed step construction generates VCSOR and VCSXOR which have optimal pixel expansion and contrast for each qualified set in the general access structure in most cases. Our scheme applies a technique to simplify the access structure, which can reduce the average pixel expansion (APE) in most cases compared with many of the results in the literature. Finally, we give some experimental results and comparisons to show the effectiveness of the proposed scheme. © 2010 IEEE.

Chen L.-B.,Ocean University of China | Chen L.-B.,University of California at San Diego | Sham L.J.,University of California at San Diego | Waks E.,U.S. National Institute of Standards and Technology
Physical Review B - Condensed Matter and Materials Physics | Year: 2012

We present a feasible scheme for performing an optically controlled phase gate between two conduction electron spin qubits in adjacent self-assembled quantum dots. Interaction between the dots is mediated by the tunneling of the valence hole state, which is activated only by applying a laser pulse of the right polarization and frequency. Combining the hole tunneling with the Pauli blocking effect, we obtain conditional dynamics for the two quantum dots, which is the essence of our gating operations. Our results are of explicit relevance to the recent generation of vertically stacked self-assembled InAs quantum dots, and show that by a design which avoids unintended dynamics the gate could be implemented in theory in the 10-ps range and with a fidelity over 90%. Our proposal therefore offers an accessible path to the demonstration of ultrafast quantum logic in quantum dots. © 2012 American Physical Society.

Gao Z.,Ocean University of China | Zhou T.,CAS Academy of Mathematics and Systems Science
Communications in Computational Physics | Year: 2014

In this work, we concern with the numerical comparison between different kinds of design points in least square (LS) approach on polynomial spaces. Such a topic is motivated by uncertainty quantification (UQ). Three kinds of design points are considered, which are the Sparse Grid (SG) points, the Monte Carlo (MC) points and the Quasi Monte Carlo (QMC) points. We focus on three aspects during the comparison: (i) the convergence properties; (ii) the stability, i.e. the properties of the resulting condition number of the design matrix; (iii) the robustness when numerical noises are present in function values. Several classical high dimensional functions together with a random ODE model are tested. It is shown numerically that (i) neither the MC sampling nor the QMC sampling introduce the low convergence rate, namely, the approach achieves high order convergence rate for all cases provided that the underlying functions admit certain regularity and enough design points are used; (ii)The use of SG points admits better convergence properties only for very low dimensional problems (say d ≤ 2); (iii)The QMC points, being deterministic, seem to be a good choice for higher dimensional problems not only for better convergence properties but also in the stability point of view. © 2014 Global-Science Press.

Li Z.-L.,Ocean University of China
Zeitschrift fur Naturforschung - Section A Journal of Physical Sciences | Year: 2010

The Jacobin doubly periodic wave solution, the Weierstrass elliptic function solution, the bell-type solitary wave solution, the kink-type solitary wave solution, the algebraic solitary wave solution, and the triangular solution of a generalized Korteweg-de Vries-modified Korteweg-de Vries equation (GKdV-mKdV) with higher-order nonlinear terms are obtained by a generalized subsidiary ordinary differential equation method (Gsub-ODE method for short). The key ideas of the Gsub-ODE method are that the periodic wave solutions of a complicated nonlinear wave equation can be constructed by means of the solutions of some simple and solvable ODE which are called Gsub-ODE with higherorder nonlinear terms. © 2010 Verlag der Zeitschrift für Naturforschung, Tübingen.

Herbeck L.S.,Leibniz Center for Tropical Marine Ecology | Unger D.,Leibniz Center for Tropical Marine Ecology | Krumme U.,Leibniz Center for Tropical Marine Ecology | Liu S.M.,Ocean University of China | Jennerjahn T.C.,Leibniz Center for Tropical Marine Ecology
Estuarine, Coastal and Shelf Science | Year: 2011

Typhoons regularly hit the coasts along the northern South China Sea during summer monsoon. However, little is known on the effects of typhoon-related heavy precipitation on estuarine dynamics and coastal ecosystems. We analyzed physico-chemical characteristics, and concentrations and composition of dissolved and suspended matter in the Wenchang/Wenjiao Estuary (WWE) on the tropical island of Hainan, China, prior to and after typhoon Kammuri in August 2008. Before the typhoon, the estuary displayed vertical and horizontal gradients. High nutrient inputs from agriculture and widespread aquaculture were to a large extent converted into biomass inside the estuarine lagoon resulting in low export of nutrients to coastal waters and a mainly autochthonous origin of total suspended matter (TSM). Heavy typhoon-associated precipitation increased river runoff, which moved the location of the estuarine salinity gradient seaward. It resulted in an export of dissolved and particulate matter to coastal waters one day after the typhoon. Dissolved nutrients increased by up to an order of magnitude and TSM increased approximately twofold compared to pre-typhoon values. Lower δ13Corg and δ15N and elevated C/N ratios of TSM together with lower chlorophyll a (chl a) concentrations indicated an increased contribution of terrestrial material originating from typhoon-induced soil erosion. Local uptake of excess nutrients inside the lagoon was inhibited because of reduced water transparency and the lack of phytoplankton, which had been washed out by the initial freshwater pulse. Two weeks after the typhoon, TSM concentration and composition had almost returned to pre-typhoon conditions. However, physico-chemical properties and nutrients were still different from pre-typhoon conditions indicating that the estuarine system had not fully recovered. Unusually high chl a concentrations in the coastal zone indicated a phytoplankton bloom resulting from the typhoon-induced nutrient export. The typhoon-induced flushing of the WWE resulted in hyposalinity, reduced water transparency, siltation, as well as temporary eutrophication of coastal waters. These are physiological stressors, which are known to impair the performance of adjacent seagrass meadows and coral reefs. The predicted increase in typhoon frequency and intensity will lead to a frequently recurring exposure of coastal ecosystems to these threats, particularly in the South China Sea region where aquaculture is widespread and tropical cyclone frequency is at a maximum. © 2011 Elsevier Ltd.

Zhao J.,University of Massachusetts Amherst | Wang Z.,Ocean University of China | Ghosh S.,University of Massachusetts Amherst | Xing B.,University of Massachusetts Amherst
Environmental Pollution | Year: 2014

This work investigated the binding behavior of phenanthrene by humic acids (HA-2 and HA-5), proteins (bovine serum albumin (BSA)), lysozyme and pepsin), and their complexes using a passive dosing technique. All sorption isotherms were fitted well with Freundlich model and the binding capability followed an order of HA-5 > HA-2 > BSA > pepsin > lysozyme. In NaCl solution, phenanthrene binding to HA-BSA complexes was much higher than the sum of binding to individual HA and BSA, while there was no enhancement for HA-pepsin. Positively charged lysozyme slightly lowered phenanthrene binding on both HAs due to strong aggregation of HA-lysozyme complexes, leading to reduction in the number of binding sites. The binding enhancement by HA-BSA was observed under all tested ion species and ionic strengths. This enhancement can be explained by unfolding of protein, reduction of aggregate size and formation of HA-BSA complexes with favorable conformations for binding phenanthrene. © 2013 Elsevier Ltd. All rights reserved.

Sun Y.,CAS Institute of Earth Environment | Clemens S.C.,Brown University | Morrill C.,University of Colorado at Boulder | Lin X.,Ocean University of China | And 2 more authors.
Nature Geoscience | Year: 2012

The last glacial period was characterized by abrupt, millennial-scale climate change. These climate fluctuations are particularly pronounced in records of the East Asian monsoon system, and seem to be linked to changes in North Atlantic circulation. Here we present records of grain size variations from the northwestern Chinese Loess Plateau, dated using optically stmulated luminescence. We reconstruct changes in the strength of the East Asian winter monsoon over the past 60,000 years and find reconstructed millennial-scale variations that are broadly correlated with temperature variations over Greenland, suggesting a common forcing. We investigate the effect of a slow-down of Atlantic meridional overturning circulation on the monsoon system using a coupled climate model simulation with added freshwater flux into the northern North Atlantic, and find a strengthening winter monsoon circulation over the regions that supply dust to the Loess Plateau and a reduction in summer monsoon precipitation over East Asia. We conclude that Atlantic meridional overturning circulation is a driver of abrupt change in the East Asian winter and summer monsoon systems, and that the northern westerlies play a role in transmitting this signal from the North Atlantic to the Asian monsoon regions.

Zhao G.,University of Hong Kong | Cawood P.A.,University of St. Andrews | Li S.,Ocean University of China | Wilde S.A.,Curtin University Australia | And 4 more authors.
Precambrian Research | Year: 2012

Geological and geophysical data indicate that the Precambrian basement of the North China Craton (NCC) formed by amalgamation of a number of micro-continental blocks. The number of blocks, when they existed and how they came together are controversial, and in particular the following issues are disputed: (1) the timing of collisional event(s) leading to the amalgamation of the Eastern and Western blocks along the Trans-North China Orogen (TNCO); (2) the polarity of the subduction between the Eastern and Western blocks; (3) the validity of an old continental block (Fuping Block) that collided with the Eastern Block at ~2.1Ga; (4) the tectonic setting of the northern margin of the NCC in the Paleoproterozoic; (5) the tectonic nature of high-pressure (HP) and ultrahigh temperature (UHT) granulite-facies events in the Khondalite Belt of the Western Block; and (6) the tectonic setting of the Paleoproterozoic Jiao-Liao-Ji Belt in the Eastern Block.Analysis and integration of available stratigraphic, structural, geochemical, metamorphic and geochronologic data enable the development of an internally consistent and coherent model for assembly and stabilization of the various Archean blocks of the NCC in the Paleoproterozoic. All metamorphic ages obtained for the TNCO are around 1.85Ga, which establishes that the final amalgamation of the Western and Eastern blocks of the craton occurred at ~1.85Ga. The TNCO is characterized by a fan-shaped pattern of structural features, with the top-to-the-NW and top-to-the-SE thrusting in the northwest and southeast, respectively. This pattern does not constrain subduction polarity for the collisional assembly of the Eastern and Western blocks. Structures in lithospheric mantle and asthenosphere in the TNCO have been significantly modified/replaced in the Mesozoic and Cenozoic, and hence the present-day orientation of these structures, even if they relate to Paleoproterozoic assembly of the craton cannot be used to infer associated subduction polarity. There are no unique structural data or available metamorphic data to supporting the existence of an old continental block that intervened between the Eastern and Western Blocks, which collided with the Eastern Block at ~2.1Ga. Available data are also inconsistent with the existence of the Paleoproterozoic Inner Mongolia-North Hebei Orogen along the northern margin of the NCC that formed through accretion of an exotic arc at ~2.3Ga and incorporated into the Paleoproterozoic Columbia (Nuna) Supercontinent at 1.92-1.85Ga. We interpret the north Hebei portion of this inferred orogen as part of the TNCO, and the Inner Mongolian portion as an independent continental block (Yinshan Block). This block is separated from the Ordos Block by the Paleoproterozoic Khondalite Belt. The high-/medium-pressure granulite facies metamorphic event in the Khondalite Belt is considered to have resulted from collision between the Yinshan and Ordos blocks to form the Western Block at ~1.95Ga, whereas the ~1.92Ga UHT metamorphism within the belt was related to the underplating or intrusion of mantle-derived magmas during the post-collisional extension. The Jiao-Liao-Ji Belt in the Eastern Block likely formed through Paleoproterozoic rifting to form the Longgang and Langrim blocks, and subsequent basin closure and collision in the period 2.2-1.9Ga. © 2012 Elsevier B.V..

Yang B.,CAS South China Botanical Garden | Yang H.,University of Minnesota | Li J.,CAS South China Botanical Garden | Li Z.,Ocean University of China | Jiang Y.,CAS South China Botanical Garden
Food Chemistry | Year: 2011

The proteins of soy sauce lees (SSLP) were hydrolysed by Alcalase in the presence of ultrasound or traditional water bath to obtain hydrolysates S2-S6. The analysis of protein content indicated that enzymatic hydrolysis could significantly improve the extraction efficiency of proteins. By determination of molecular weight distribution, >10 and 5-10. KDa fractions of native SSLP (S1) decreased during hydrolysis, whilst 3-5. KDa fraction increased. Gradual increases of free, total and antioxidant amino acids were observed for S1-S4, and the differences between S4 and S6 were slight. Tyrosine was the major free amino acid of S1-S6, whilst glutamic acid had the highest amount in total amino acid composition. S2-S6 showed stronger DPPH radical scavenging activities in a dose-dependent manner than S1. All the results suggested that ultrasound treatment showed an inhibition behaviour on the enzymatic hydrolysis of SSLP. © 2010 Elsevier Ltd.

Wu H.,China University of Geosciences | Wu H.,Ocean University of China | Zhang S.,China University of Geosciences | Feng Q.,Wuhan University | And 3 more authors.
Gondwana Research | Year: 2012

The mass extinction at the end of Permian was followed by a prolonged recovery process with multiple phases of devastation-restoration of marine ecosystems in Early Triassic. The time framework for the Early Triassic geological, biological and geochemical events is traditionally established by conodont biostratigraphy, but the absolute duration of conodont biozones are not well constrained. In this study, a rock magnetic cyclostratigraphy, based on high-resolution analysis (2440 samples) of magnetic susceptibility (MS) and anhysteretic remanent magnetization (ARM) intensity variations, was developed for the 55.1-m-thick, Early Triassic Lower Daye Formation at the Daxiakou section, Hubei province in South China. The Lower Daye Formation shows exceptionally well-preserved lithological cycles with alternating thinly-bedded mudstone, marls and limestone, which are closely tracked by the MS and ARM variations. Power spectral, wavelet and amplitude modulation (AM) analyses of the ARM and MS series reveal strong evidence for the presence of Milankovitch to sub-Milankovitch frequencies dominated by precession index signal and 4-5. ka cycles. Cycles expressed by variations in MS and ARM were likely controlled by changes in the input of fine-grained detrital magnetite, which in turn may have been driven by astronomically induced changes in monsoon intensity in the equatorial eastern Paleotethys during the Early Triassic greenhouse period.On the basis of the 100-ka tuning results, the astronomically constrained duration of the Induan stage is 1.16Ma, with the Griesbachian and Dienerian substages of 490ka and 670ka, respectively. The new astronomical time scale also provides time constraints for the conodont and bivalve biozones and the carbonate carbon isotope (δ 13C) records of the Lower Triassic Daye Formation. Time constraints for the conodont biozones include 34ka for Hindeodus parvus, 24ka for Isarcicella staschei-I. isarcica, 366ka for Neogondolella planata-Ng. carinata, 66ka for Neogondolella discreta, 255ka for Neospathodus kummeli and 415ka for Neospathodus dieneri. The duration for the negative δ 13C shift from high δ 13C values near the Indun/Olenekian boundary to the lowest value in the Early Smithian is estimated as 430ka. Global comparison indicates that Milankovitch and 4-5ka sub-Milankovitch forcing depositional rhythms may have been common in tropical and sub-tropical carbonate platforms during the Early and Middle Triassic time. The ultimate control on the 4-5ka cycles may have been millennial-scale fluctuations in solar insolation. © 2011 International Association for Gondwana Research.

Fang J.,Ocean University of China
Fuzzy Sets and Systems | Year: 2014

Using the intrinsic lattice-valued inclusion orders of L-subsets and of stratified L-filters, the concept of a stratified L-preuniform convergence structure is proposed. This convergence structure is asymmetric and can be used to establish a framework of asymmetric lattice-valued space structures. The category of stratified L-preuniform convergence spaces is introduced and some categorical properties are presented. A reflective subcategory of stratified L-preuniform convergence spaces is found that is categorically isomorphic to strong stratified L-convergence spaces (originally called stratified L-ordered convergence spaces). Several subcategories of stratified L-preuniform convergence spaces are established and relations between the different subcategories are presented. We conclude that stratified L-preuniform convergence structures introduced here could play a role in the framework of lattice-valued asymmetric space structures in lattice-valued topology. © 2013 Elsevier B.V.

Zhou H.Y.,Henan University of Science and Technology | Jiang L.J.,Henan University of Science and Technology | Cao P.P.,Henan University of Science and Technology | Li J.B.,Henan University of Science and Technology | Chen X.G.,Ocean University of China
Carbohydrate Polymers | Year: 2015

Chitosan is non-toxic, biocompatible and biodegradable polysaccharide composed of glucosamine and derived by deacetylation of chitin. Chitosan thermosensitive hydrogel has been developed to form a gel in situ, precluding the need for surgical implantation. In this review, the recent advances in chitosan thermosensitive hydrogels based on different glycerophosphate are summarized. The hydrogel is prepared with chitosan and β-glycerophosphate or αβ-glycerophosphate which is liquid at room temperature and transits into gel as temperature increases. The gelation mechanism may involve multiple interactions between chitosan, glycerophosphate, and water. The solution behavior, rheological and physicochemical properties, and gelation process of the hydrogel are affected not only by the molecule weight, deacetylation degree, and concentration of chitosan, but also by the kind and concentration of glycerophosphate. The properties and the three-dimensional networks of the hydrogel offer them wide applications in biomedical field including local drug delivery and tissue engineering. © 2014 Elsevier Ltd. All rights reserved.

Guo F.,Shandong University | Xu J.,Ocean University of China | Zhang X.,Shandong University | Zhu B.,Shandong University
Inorganica Chimica Acta | Year: 2010

Four novel metal coordination polymers, [Cd(dpa)(H2O)] n (1), [Cd(dpa)(2,2′-bipy)]n (2), {[Cd 2(dpa)2(4,4′-bipy)3](4,4′-bipy) (H2O)2}n (3) and [Cd(dpa)(bim) 2(H2O)]}n (4) (H2dpa = 2,4′-biphenyl-dicarboxylic acid, 2,2′-bipy = 2,2′-bipyridine, 4,4′-bipy = 4,4′-bipyridine, bim = benzimidazole), have been synthesized and structurally characterized by elemental analysis, IR and X-ray diffraction. Single-crystal X-ray analyses reveal that the 2,4′-diphenic acids acts as bridging ligands, exhibiting rich coordination modes to link metal ions: bis-monodentate, bidentate chelating, chelating/bridging, monoatomic bridging and monodentate modes. In addition, the luminescent properties for compound 1-4 are also investigated in this work. © 2010 Elsevier B.V. All rights reserved.

Yao X.H.,Ocean University of China | Zhang L.,Environment Canada
Atmospheric Chemistry and Physics | Year: 2012

Fog-processed aerosols were identified and analyzed in detail from a large-sized database in which size-segregated atmospheric particles and gases were simultaneously measured at eight Canadian rural sites. In ten samples collected during or following fog events, at least one supermicron mode of particulate NH4+ was observed. The supermicron modes were likely associated with fog events since they were absent on non-fog days. The supermicron mode of NH4 + in the 5-10 μm size range probably reflected the direct contribution from fog droplets. Based on detailed analysis of the chemical compositions and the extent of neutralization, the supermicron mode of NH4 + in the 1-4 μm size range was believed to be caused by fog-processing of ammonium salt aerosols. These aerosol particles consisted of incompletely neutralized sulfuric acid aerosols in NH3-poor conditions or a mixture of ammonium nitrate and ammonium sulfate aerosols in NH3-rich conditions. Interstitial aerosols and fog droplets presented during fog events likely yielded a minor direct contribution to the measured NH4 +. The mass median aerodynamic diameter (MMAD) of the 1-4 μm mode of NH4+ strongly depended on ambient temperature (T ) and can be grouped into two regimes. In one regime, the MMAD was between 1.1 and 1.7 Î1/4m in four samples, when fog occurred at T > 0 °C, and in two samples, at T >-3 °C. The MMAD of NH4 + in this size range was also observed in various atmospheric environments, as discussed in the literature. In the other regime, the MMAD was between 2.8 and 3.4 μm in four samples when fog occurred at T <-4 °C, a phenomenon that was first observed in this study. The MMAD was not related to chemical composition and concentration of ammonium salts. Further investigations are needed in order to fully understand the cause of the MMAD. The larger supermicron mode of ammonium salts aerosol observed at T <-4 °C has added new knowledge on the size distributions and chemical compositions of fog-processed aerosols under various ambient conditions. © 2012 Author(s).

Dong C.,Qingdao Agricultural University | Wang J.,Ocean University of China
Aquaculture Research | Year: 2013

Fructooligosaccharides (FOS) are widely researched as prebiotics and immunostimulants in humans and terrestrial animals. However, limited researches on immune functions of FOS were reported in crustacean. In the present study, red swamp crayfish Procambarus clarkii were fed with different concentrations of FOS (2.0, 5.0, 8.0, 10.0 g kg-1 diet), and then the immunostimulatory effects of FOS were evaluated by measuring immune parameters and examining immune-related gene expression. PO and SOD activities were significantly increased in groups fed with 8.0 or 10.0 g kg-1 of FOS compared with those in control group. In addition, significant elevations of SOD and phagocytic activities were also observed in group fed with 5.0 g kg-1 of FOS. Among examined immune-related genes, expressions of crustin1, lysozyme, SOD and pro-PO were significantly up-regulated by feeding with 8.0 or 10.0 g kg-1 of dietary FOS. Survival rates of crayfish challenged with Aeromonas hydrophila were significantly improved by feeding with 5.0, 8.0 or 10.0 g kg-1 of dietary FOS for 30 days. Phagocytic activities and bacterial clearance efficiencies were also significantly increased in groups fed with 8.0 or 10.0 g kg-1 of FOS. The results indicated that dietary FOS effectively induced innate immune responses of red swamp crayfish in a dose-dependent way and could be used as potential immunostimulant in crustacean. © 2012 John Wiley & Sons Ltd.

Yang H.,Ocean University of China | Li N.,Shanghai JiaoTong University | Li S.,Shanghai JiaoTong University
Asian Journal of Control | Year: 2011

In this paper, a new data-driven model predictive control (MPC), based on bilinear subspace identification, is considered. The system's nonlinear behavior is described with a bilinear subspace predictor structure in an MPC framework. Thus, the MPC formulation results in a fixed structure objective function with constraints regardless of the underlying nonlinearity. For unconstrained systems, the identified subspace predictor matrices can be directly used as controller parameters. Therefore, we design optimization algorithms that exploit this feature. The open-loop optimization problem of MPC that is nonlinear in nature is solved with series quadratic programming (SQP) without any approximations. The computational efficiency already demonstrated with the current formulation presents further opportunities to enable online control of nonlinear systems. These improvements and close integration of modeling and control also eliminate the intermediate design step, which provides a means for data-driven controller design in generalized predictive controller (GPC) framework. Finally, the proposed control approach is illustrated with a verification study of a nonlinear continuously stirred tank reactor (CSTR) system. © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society.

Li J.,Qingdao Agricultural University | Tang G.-Y.,Ocean University of China | Zhang P.,Qingdao Agricultural University | Zou J.,Qingdao Agricultural University
Asian Journal of Control | Year: 2012

The problems of fault diagnosis and fault-tolerant control are considered for systems with measurement delays. In contrast to the present fault diagnosis and fault-tolerant control approaches, which consider only the input delay and/or state delay, the main contribution of this paper consists of proposing a new observer-based reduced-order fault diagnoser construction approach and a design approach to dynamic self-restore fault-tolerant control law for systems with measurement delays. First, the time-delay system is transformed into a delay-free system in form by a special functional-based delay-free transformation approach for measurement delays. Then, the fault diagnosis is realized online via the proposed reduced-order fault diagnoser. Using the results of fault diagnosis, two dynamic self-restore control laws are designed to make the system isolated from faults. A numerical example demonstrates the feasibility and validity of the proposed scheme. © 2012 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society.

Yang P.,Yunnan Normal University | Tang Q.,Ocean University of China
Electrochimica Acta | Year: 2015

Alloys are a class of rising counter electrode (CE) electrocatalyst candidates for dye-sensitized solar cells (DSSCs). We present here the mild solution synthesis of NiM (M = Pt, Pd) alloys using zinc oxide nanorod templates and employment as CE electrocatalysts for liquid-junction DSSC applications. Due to the good matching of work functions to redox potential of I-/I3 - redox couples and reduced charge-transfer resistance at CE/electrolyte interface, the electrocatalytic activity of NiPt CE and therefore cell performances have been markedly enhanced, yielding a promising power conversion efficiency of 8.27% in the liquid-junction DSSC platform. © 2015 Elsevier Ltd. All rights reserved.

Zhang T.-Y.,Tsinghua University | Wu Y.-H.,Tsinghua University | Zhu S.-F.,Tsinghua University | Li F.-M.,Ocean University of China | Hu H.-Y.,Tsinghua University
Bioresource Technology | Year: 2013

Cultivating microalgae heterotrophically could overcome the light dependency, and thus increase the yield of microalgal lipid per unit area. In this study, three newly isolated strains of microalgae (Scenedesmus sp. ZTY2, Scenedesmus sp. ZTY3 and Chlorella sp. ZTY4) from a domestic wastewater treatment plant were heterotrophically cultivated in domestic wastewater with no illumination. During the cultivation, the algal densities of Scenedesmus species and Chlorella species were increased by 203.0% and 60.5% comparing with the initial densities, respectively. After 11-day cultivation, the lipid contents of Scenedesmus sp. ZTY2, Scenedesmus sp. ZTY3 and Chlorella sp. ZTY4 reached 69.1%, 55.3% and 79.2%, respectively. The DOC removal efficiencies of these three strains were 63.4%, 52.9% and 64.4%, and the biomass yield were 1.65, 1.98 and 2.31. mg. biomass/mg DOC, respectively. This is the first report about the heterotrophic cultivation of microalgae strains for domestic wastewater treatment and lipid production under dark condition. © 2013 Elsevier Ltd.

Kao Y.,Harbin Institute of Technology | Xie J.,Ocean University of China | Wang C.,Harbin Institute of Technology | Karimi H.R.,University of Agder
Automatica | Year: 2015

This paper is focused on designing an H∞ sliding-mode control for a class of neutral-type stochastic systems with Markovian switching parameters and nonlinear uncertainties. An H∞ non-fragile observer subjected to the transition rates of the switching mode is firstly constructed. By some specified matrices, the connections among the designed sliding surfaces corresponding to every mode are established. Then, the state-estimation-based sliding mode control law is designed to guarantee the reachability of the sliding surface in finite time interval. Furthermore, a stochastic stability criterion is established for all admissible uncertainties, which can guarantee the error system and sliding mode dynamics to be asymptotically stochastic stable with a given disturbance attenuation level. Finally, an example is provided to illustrate the efficiency of the proposed method. © 2014 Elsevier. Ltd All rights reserved.

Li G.,CAS Research Center for Eco Environmental Sciences | Zhao Z.,Ocean University of China | Liu J.,CAS Research Center for Eco Environmental Sciences | Jiang G.,CAS Research Center for Eco Environmental Sciences
Journal of Hazardous Materials | Year: 2011

A thiol-functionalized magnetic mesoporous silica material (called SH-mSi@Fe3O4), synthesized by a modified Stöber method, has been investigated as a convenient and effective adsorbent for heavy metal ions. Structural characterization by powder X-ray diffraction, N2 adsorption-desorption isotherm, Fourier transform infrared spectroscopy and elemental analyses confirms the mesoporous structure and the organic moiety content of this adsorbent. The high saturation magnetization (38.4emu/g) make it easier and faster to be separated from water under a moderate magnetic field. Adsorption kinetics was elucidated by pseudo-second-order kinetic equation and exhibited 3-stage intraparticle diffusion mode. Adsorption isotherms of Hg and Pb fitted well with Langmuir model, exhibiting high adsorption capacity of 260 and 91.5mg of metal/g of adsorbent, respectively. The distribution coefficients of the tested metal ions between SH-mSi@Fe3O4 and different natural water sources (groundwater, lake water, tap water and river water) were above the level of 105mL/g. The material was very stable in different water matrices, even in strong acid and alkaline solutions. Metal-loaded SH-mSi@Fe3O4 was able to regenerate in acid solution under ultrasonication. This novel SH-mSi@Fe3O4 is suitable for repeated use in heavy metal removal from different water matrices. © 2011 Elsevier B.V.

Xu X.,University of Nebraska - Lincoln | Wang J.,University of Nebraska - Lincoln | Henze D.K.,University of Colorado at Boulder | Qu W.,Ocean University of China | Kopacz M.,National Oceanic and Atmospheric Administration
Journal of Geophysical Research: Atmospheres | Year: 2013

We present a new top-down approach that spatially constrains the amount of aerosol emissions using satellite (Moderate Resolution Imaging Spectroradiometer (MODIS)) observed radiances with the adjoint of a chemistry transport model (GEOS-Chem). This paper aims to demonstrate the approach through applying it to a case study that yields the following emission estimates over China for April 2008: 1.73 Tg for SO2, 0.72 Tg for NH3, 1.38 Tg for NOx, 0.10 Tg for black carbon, and 0.18 Tg for organic carbon from anthropogenic sources, which reflects, respectively, a reduction of 33.5%, 34.5%, 18.8%, 9.1%, and 15% in comparison to the prior bottom-up inventories of INTEX-B 2006. The mineral dust emission from the online dust entrainment and mobilization module is reduced by 56.4% of 19.02 to 8.30 Tg. Compared to the prior simulation, the posterior simulation shows a much better agreement with the following independent measurements: aerosol optical depth (AOD) measured by AERONET sun-spectrophotometers and retrieved from Multi-angle Imaging SpectroRadiometer (MISR), atmospheric NO2 and SO2 columnar amount retrieved from Ozone Monitoring Instrument (OMI), and in situ data of sulfate-nitrate-ammonium and PM10 (particular matter with aerodynamic diameter less than 10 μm) mass concentrations over both anthropogenic pollution and dust source regions. Assuming the bottom-up (prior) anthropogenic emissions are the best estimates for their base year of 2006, the overwhelming reduction in the posterior (top-down) estimate indicates less emission in April 2008 especially for the SO2 tracer in the central and eastern parts of China, and/or an overestimation in the prior emission. The former is supported by the AOD change detected by MODIS and MISR sensors, while the latter is likely the case for NOx and NH3 emissions because no evidence shows that their atmospheric concentration has declined over China. With the promising results shown in this study, continuous efforts are needed toward a holistic and comprehensive inversion of emission using multisensor remote sensing data (of trace gases and aerosols) for constraining aerosol primary and precursor emissions at various temporal and spatial scales. Key Points Optimize speciated emission with MODIS radiance and adjoint model. Comprehensive evaluation with MISR aerosol and OMI NO2 and SO2 data. Case study shows that aerosol emission over China is reduced from 2006 to 2008. © 2013. American Geophysical Union. All Rights Reserved.

Zhang H.,CAS Institute of Automation | Zhong G.,Ocean University of China
Knowledge-Based Systems | Year: 2016

This paper presents a general framework for short text classification by learning vector representations of both words and hidden topics together. We refer to a large-scale external data collection named "corpus" which is topic consistent with short texts to be classified and then use the corpus to build topic model with Latent Dirichlet Allocation (LDA). For all the texts of the corpus and short texts, topics of words are viewed as new words and integrated into texts for data enriching. On the enriched corpus, we can learn vector representations of both words and topics. In this way, feature representations of short texts can be performed based on vectors of both words and topics for training and classification. On an open short text classification data set, learning vectors of both words and topics can significantly help reduce the classification error comparing with learning only word vectors. We also compared the proposed classification method with various baselines and experimental results justified the effectiveness of our word/topic vector representations. © 2016 Elsevier B.V. All rights reserved.

Xiang B.,University of Hawaii at Manoa | Wang B.,University of Hawaii at Manoa | Yu W.,State Oceanic Administration | Xu S.,University of Hawaii at Manoa | Xu S.,Ocean University of China
Geophysical Research Letters | Year: 2013

The western North Pacific (WNP) Subtropical High (WNPSH) is a controlling system for East Asian Summer monsoon and tropical storm activities, whereas what maintains the anomalous summertime WNPSH has been a long-standing riddle. Here we demonstrate that the local convection-wind-evaporation-SST (CWES) feedback relying on both mean flows and mean precipitation is key in maintaining the WNPSH, while the remote forcing from the development of the El Niño/Southern Oscillation is secondary. Strikingly, the majority of strong WNPSH cases exhibit anomalous intensification in late summer (August), which is dominantly determined by the seasonal march of the mean state. That is, enhanced mean precipitation associated with strong WNP monsoon trough in late summer makes atmospheric response much more sensitive to local SST forcing than early summer. © 2013 American Geophysical Union. All Rights Reserved.

Yu K.,Ocean University of China | Yu K.,University of Hawaii at Manoa | Qu T.,University of Hawaii at Manoa
Journal of Climate | Year: 2013

Analysis of the 62-yr hindcast outputs from an eddy-resolving ocean general circulation model reveals a prominent decadal variability in the upper-layer (0-745 m) Luzon Strait transport (LST), a key component of the South China Sea throughflow. This variability is in phase with the basin-scale wind stress anomalies associated with the Pacific decadal oscillation (PDO). A composite analysis shows that during the positive phase of the PDO, the Aleutian low and its related positive wind stress curl anomalies intrude southward, reducing the trade winds and enhancing the westerly wind anomalies in the tropical North Pacific. In response, the North Equatorial Current bifurcation shifts northward, resulting in a weaker Kuroshio east of Luzon and consequently a stronger South China Sea throughflow in the upper 745 m. © 2013 American Meteorological Society.

Wang C.,National Oceanic and Atmospheric Administration | Zhang L.,National Oceanic and Atmospheric Administration | Zhang L.,University of Miami | Zhang L.,Ocean University of China | And 2 more authors.
Journal of Climate | Year: 2013

The response of freshwater flux and sea surface salinity (SSS) to the Atlantic warm pool (AWP) variations from seasonal to multidecadal time scales is investigated by using various reanalysis products and observations. All of the datasets show a consistent response for all time scales:Alarge (small)AWPis associated with a local freshwater gain (loss) to the ocean, less (more) moisture transport across Central America, and a local low (high) SSS. The moisture budget analysis demonstrates that the freshwater change is dominated by the atmospheric mean circulation dynamics, while the effect of thermodynamics is of secondary importance. Further decomposition points out that the contribution of the mean circulation dynamics primarily arises from its divergent part, which mainly reflects the wind divergent change in the low level as a result of SST change. In association with a large (small) AWP, warmer (colder) than normal SST over the tropical North Atlantic can induce anomalous low-level convergence (divergence), which favors anomalous ascent (decent) and thus generates more (less) precipitation. On the other hand, a large (small) AWP weakens (strengthens) the trade wind and its associated westward moisture transport to the eastern North Pacific across Central America, which also favors more (less) moisture residing in the Atlantic and hence more (less) precipitation. The results imply that variability of freshwater flux and ocean salinity in the North Atlantic associated with the AWP may have the potential to affect the Atlantic meridional overturning circulation. © 2013 American Meteorological Society.

Wei H.,Ocean University of China
Wei sheng wu xue bao = Acta microbiologica Sinica | Year: 2010

Microbial secondary metabolites have a wide range of biological activities due to their structural diversity and have been proved a major source for drug lead compounds. However,the traditional method of a single culture restricts the metabolic pathways of microorganisms and as a result many metabolites cannot be formed. Recently,it has attracted much attention to use various techniques to activate those metabolic pathways restricted by the traditional method to get metabolic products with rich variety of structures. "One strain many compounds" (OSMAC) is a simple and effective approach for activating metabolic pathways and has been successfully applied. This review summarizes the common strategies of the OSMAC approach (altering cultivation parameters, co-cultivation, addition of enzyme inhibitors, etc) and the recent advances of OSMAC combined with genomics scanning. This review also introduces the research of our studies using the OSMAC approach on a fungus Spicaria elegans KLA03 which yielded a series of cytochalasins.

Kong M.,Korea University | Chen X.,Ocean University of China | Park H.,Korea University
Carbohydrate Polymers | Year: 2011

Hyaluronic acid (HA) was modified into an amphiphile through esterification between the carboxyl and hydroxyl moieties on glycerol-α-monostearate (GMS). The conjugation was verified via FT/IR and 1H NMR. Ultrasonification and solvent evaporation were used to prepare a fine oil/water/surfactant (O/W/S) nanoemulsion consisting of methylene chloride as the oil phase (O), HA water solution (W), and non-ionic Tween-80 and Span-20 as surfactant (S). The optimal ratio of the disperse phase was screened in nanoemulsion formed without HA-GMS. Tween-80 and Span-20 at the required hydrophilic-lipophilic balance (HLB) of 12.5 and a ratio of O/S (ROS) of 60, which accounted for 5% (w/w) in the emulsion system, was determined to be the optimal disperse phase ratio, giving rise to the smallest droplet size (39.7 nm) and lower protein dispersibility (0.341). The smallest droplet size of the HA-GMS nanoemulsion was 42.0 nm, with contraction to 38.9 nm evident after 96 h storage. Higher degree of substitution or lower molecular weight was favorable for the formation of smaller emulsified droplets. Nanoemulsions were characterized morphologically by electronic microscopy. © 2010 Elsevier Ltd. All rights reserved.

Kong M.,Korea University | Chen X.G.,Ocean University of China | Kweon D.K.,Kolon Life Science Research Institute | Park H.J.,Korea University
Carbohydrate Polymers | Year: 2011

An alcohol-free oil/water hyaluronic acid nanoemulsion was developed to be applied as transdermal carrier for active lipophilic ingredient. In vitro hemolysis, skin penetration and histological examinations were carried out using α-tocopherol as model ingredient to assess skin permeability and bioavailability. Without any chemical enhancers, nanoemuslion performed desirable skin permeable capacity, being able to penetrate across stratum corneum and diffuse deeper into dermis compared with the control group (ethanol solution) via follicular and intercellular pathway. Penetration mechanism was preliminarily studied and suggested to be closely concerned with transmembrane concentration gradient, carrier characteristics and penetration enhancers. No irritation has been found in dermis and skin surface indicated hyaluronic acid nanoemulsions could be successfully used as purcutaneous delivery carrier of active lipophilic ingredient and favorable for drug and cosmetic applications. © 2011 Elsevier Ltd All rights reserved.

Tang Q.,Ocean University of China | Yang P.,Yunnan Normal University
Journal of Materials Chemistry A | Year: 2016

With the abundance of traditional energy conversion devices such as solar cells, fuel cells, lithium batteries and supercapacitors, the integration of graphene with water is an increasingly used method for promising electricity generation (including current, voltage, and power) in the last few years. We present here a review on the significant advances in tailored graphene-based materials for unprecedented power generation by flowing, raining, waving, or penetrating water. This article highlights the potential principles behind the electric signals to guide the design and synthesis of graphene-based systems for emerging power generation methods. Use of the peculiar performances of creating electric signals, the methodologies of constructing advanced devices using these graphene-based electrodes for real applications and identification of the challenges facing the water-enabled graphene for electricity generation are also discussed. © 2016 The Royal Society of Chemistry.

Liu J.,Chinese Academy of Sciences | Ma L.,Ocean University of China | Li C.,HIGH-TECH | Zhang Z.,HIGH-TECH | And 4 more authors.
Molecular Oncology | Year: 2013

Malignant uveal melanoma severely damages eye function and is prone to metastasize to other organs. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising agent to treat uveal melanoma because of its induction of apoptosis in cancer cells both at primary and metastatic sites. However, TRAIL therapy lacks tumor specificity in the current delivery systems for uveal melanoma treatment, thereby causing cytotoxiciy to normal tissues. To improve uveal melanoma specificity of adenovirus-based TRAIL introduction, we used miRNA response elements (MREs) of miR-34a, miR-137 and miR-182, which have been shown to have reduced expression in uveal melanoma cells, to regulate its expression. miR-34a, miR-137 and miR-182 all had lower expression levels in uveal melanoma cell lines, compared with normal cells. MREs-regulated luciferase activity was reduced in normal cell lines, but not significantly attenuated in uveal melanoma cells. The infection of MRE-regulated TRAIL-expressing adenoviral vector (Ad-TRAIL-3MREs) led to high level of TRAIL expression in uveal melanoma cell lines, but not in normal cells. Strong expression of TRAIL had a high anti-tumor capacity by inducing apoptosis in uveal melanoma cells. In contrast, Ad-TRAIL-3MREs had no cytotoxicity to normal cell lines. Animal experiments further confirmed tumor-suppressing effect of Ad-TRAIL-3MREs on uveal melanoma xenografts and its biosafety to hepatic tissues. Collectively, we constructed an MRE-directed TRAIL-expressing adenoviral vector and provided evidence that this vector possessed high anti-tumor activity and uveal melanoma specificity. © 2013.

Mignot A.,Massachusetts Institute of Technology | Claustre H.,CNRS Oceanography Laboratory of Villefranche | Uitz J.,CNRS Oceanography Laboratory of Villefranche | Poteau A.,CNRS Oceanography Laboratory of Villefranche | And 2 more authors.
Global Biogeochemical Cycles | Year: 2014

We deployed four Bio-Argo profiling floats in various oligotrophic locations of the Pacific subtropical gyres and Mediterranean Sea to address the seasonal phytoplankton dynamics in the euphotic layer and explore its dependence on light regime dynamics. Results show that there is a similar phytoplankton biomass seasonal pattern in the four observed oceanic regions. In the lower part of the euphotic layer, the seasonal displacement of the deep chlorophyll maximum (DCM) is light driven. During winter, the chlorophyll a concentration ([Chl a]) always increases in the upper euphotic mixed layer. This increase always results from a photoacclimation to the reduced irradiance. Depending on the location, however, the concentration can also be associated with an actual increase in biomass. The winter increase in [Chl a] results in an increase in irradiance attenuation that impacts the position of the isolume (level where the daily integrated photon flux is constant) and DCM, which becomes shallower. In summer when the [Chl a] in the upper layer decreases along with light attenuation, the DCM deepens and becomes closer to (and sometimes reaches) the nitracline, which enhances the phytoplankton biomass at the DCM. The bio-optical mechanisms and their relationship to light regimes that are revealed by the time series appear to be generic and potentially characteristic of all of the areas where a DCM forms, which is 50% of the open ocean. © 2014. American Geophysical Union.

Zhang S.,Ocean University of China
Developmental and comparative immunology | Year: 2013

Both innate and adaptive immune-relevant factors are transferred from mother to offspring in fishes. These maternally-transferred factors include IgM, lysozymes, lectin, cathelicidin and complement components. Recently, yolk proteins, phosvitin and lipovitellin, have been shown to be maternally-transferred factors, functioning in the defense of teleost larvae against pathogens. Among these factors, the mode of action of complement components and yolk proteins has been explored, whereas that of all the other factors remains elusive. At present, the transfer mechanisms of maternally-derived immune factors are largely unknown although those of IgM and yolk protein transmission from mother to offspring have been reported in some fishes. Maternal transfer of immunity is affected by many elements, including biological factors, such as age and maturation, and environmental conditions experienced by brood fish, such as pathogens and nutritional supply. Practically, the manipulation of maternal immunity transfer can be used to enhance the survival rate of fish larvae. Copyright © 2012 Elsevier Ltd. All rights reserved.

Patricola C.M.,Texas A&M University | Chang P.,Texas A&M University | Chang P.,Ocean University of China | Saravanan R.,Texas A&M University
Nature Geoscience | Year: 2016

El Nino/Southern Oscillation, the dominant mode of interannual climate variability, strongly influences tropical cyclone activity. During canonical El Nino, the warm phase, Atlantic tropical cyclones are suppressed. However, the past decades have witnessed different El Nino characteristics, ranging from warming over the east Pacific cold tongue in canonical events to warming near the warm pool, known as warm pool El Nino or central Pacific El Nino. Global climate models project possible future increases in intensity of warm pool El Nino. Here we use a climate model at a resolution sufficient to explicitly simulate tropical cyclones to investigate how these flavours of El Nino may affect such cyclones. We show that Atlantic tropical cyclones are suppressed regardless of El Nino type. For the warmest 10% of each El Nino flavour, warm pool El Nino is substantially less effective at suppressing Atlantic tropical cyclones than cold tongue El Nino. However, for the same absolute warming intensity, the opposite is true. This is because less warming is required near the warm pool to satisfy the sea surface temperature threshold for deep convection, which leads to tropical cyclone suppression through vertical wind shear enhancements. We conclude that an understanding of future changes in not only location, but also intensity and frequency, of El Nino is important for forecasts and projections of Atlantic tropical cyclone activity. © 2016 Macmillan Publishers Limited.

Zhao J.,Ocean University of China
International journal of molecular sciences | Year: 2013

A series of novel potential DNA bis-intercalators were designed and synthesized, in which two glucuronic acids were linked by ethylenediamine, and the glucuronic acid was coupled with various chromophores, including quinoline, acridine, indole and purine, at the C-1 position. The preliminary binding properties of these compounds to calf thymus DNA (CT-DNA) have been investigated by UV-absorption and fluorescence spectroscopy. The results indicated that all the target compounds can interact with CT-DNA, and the acridine derivative, 3b, showed the highest key selection vector (KSV) value, which suggested that compound 3b binds most strongly to CT-DNA.

Wang Y.,Jinan University | Smith Jr. W.O.,Virginia Institute of Marine Science | Wang X.,Ocean University of China | Li S.,South China Normal University
Geophysical Research Letters | Year: 2010

Recent investigations into the role of carbon dioxide on phytoplankton growth and composition have clearly shown differential effects among species and assemblages, suggesting that increases in oceanic CO2 may play a critical role in structuring lower trophic levels of marine systems in the future. Furthermore, alarming increases in the occurrence of harmful algal blooms (HABs) in coastal waters have been observed, and while not uniform among systems, appear in some manner to be linked to human impacts (eutrophication) on coastal systems. Models of HABs are in their infancy and do not at present include sophisticated biological effects or their environmental controls. Here we show that subtle biological responses occur in the HAB species Phaeocystis globosa Scherffel as a result of CO2 enrichment induced by gentle bubbling. The alga, which has a polymorphic life history involving the formation of both colonies and solitary cells, exhibited altered growth rates of colonial and solitary forms at [CO2] of 750 ppm, as well as increased colony formation. In addition, substantial modifications of elemental and photosynthetic constituents of the cells (C cell-1, N cell -1, potential quantum yield, chl a cell-1) occurred under elevated CO2 concentrations compared to those found at present CO2 levels. In contrast, other individual and population variables (e.g., colony diameter, total chlorophyll concentration, carbon/nitrogen ratio) were unaffected by increased CO2. Our results suggest that predictions of the future impacts of Phaeocystis blooms on coastal ecosystems and local biogeochemistry need to carefully examine the subtle biological responses of this alga in addition to community and ecosystem effects. Copyright © 2010 by the American Geophysical Union.

Li H.,Ocean University of China | Li P.,China Classification Society | Hu S.L.J.,University of Rhode Island
Applied Ocean Research | Year: 2012

Accurate estimate of the modal parameters of an offshore structure is crucial to many practical engineering issues, such as finite element (FE) model updating/validation, damage detection, etc. Using noisy acceleration signals collected from a step-relaxation test of a jacket-type offshore platform, we estimate its modal frequencies and damping ratios by an extended Prony's method, which includes a noise removal procedure to yield filtered signals before implementing the classical Prony's method on the filtered signals. To validate the applicability of the proposed approach, numerical simulations were firstly performed. Investigating corrupted relaxation response signals simulated from a FE model of the test platform, we conclude that the proposed approach is very accurate on estimating the modal parameters. A significant improvement can be achieved when the filtered, rather than the originally measured, signals are used. Using sea test data measured from accelerometers mounted at three different locations of the test platform, we find that the modal parameters estimated from the filtered signals of the three locations separately are in excellent agreement. © 2012 Elsevier Ltd.

Msanne J.,University of Nebraska - Lincoln | Xu D.,University of Nebraska - Lincoln | Xu D.,Ocean University of China | Konda A.R.,University of Nebraska - Lincoln | And 4 more authors.
Phytochemistry | Year: 2012

Microalgae are emerging as suitable feedstocks for renewable biofuel production. Characterizing the metabolic pathways involved in the biosynthesis of energy-rich compounds, such as lipids and carbohydrates, and the environmental factors influencing their accumulation is necessary to realize the full potential of these organisms as energy resources. The model green alga Chlamydomonas reinhardtii accumulates significant amounts of triacylglycerols (TAGs) under nitrogen starvation or salt stress in medium containing acetate. However, since cultivation of microalgae for biofuel production may need to rely on sunlight as the main source of energy for biomass synthesis, metabolic and gene expression changes occurring in Chlamydomonas and Coccomyxa subjected to nitrogen deprivation were examined under strictly photoautotrophic conditions. Interestingly, nutrient depletion triggered a similar pattern of early synthesis of starch followed by substantial TAG accumulation in both of these fairly divergent green microalgae. A marked decrease in chlorophyll and protein contents was also observed, including reduction in ribosomal polypeptides and some key enzymes for CO 2 assimilation like ribulose-1,5-bisphosphate carboxylase/oxygenase. These results suggest that turnover of nitrogen-rich compounds such as proteins may provide carbon/energy for TAG biosynthesis in the nutrient deprived cells. In Chlamydomonas, several genes coding for diacylglycerol:acyl-CoA acyltransferases, catalyzing the acylation of diacylglycerol to TAG, displayed increased transcript abundance under nitrogen depletion but, counterintuitively, genes encoding enzymes for de novo fatty acid synthesis, such as 3-ketoacyl-ACP synthase I, were down-regulated. Understanding the interdependence of these anabolic and catabolic processes and their regulation may allow the engineering of algal strains with improved capacity to convert their biomass into useful biofuel precursors. © 2011 Elsevier Ltd. All rights reserved.

Pang H.-P.,Qingdao University of Science and Technology | Tang G.-Y.,Ocean University of China
ICIC Express Letters | Year: 2010

The problem of robustifying optimal linear quadratic regulators (LQRs) for a class of nonlinear systems with uncertainties is considered in this paper. Firstly, by using a series-based approximate approach, the nonlinear two-point boundary value (TPBV) problem, which is derived from the necessary optimality conditions, is transformed into that of solving a series of linear TPBV iterative formulas. An approximation solution to LQR problem for nonlinear systems without uncertainties is obtained. Then, the sliding mode control theory is used to robustify the LQR. As a result, the system is global robust to uncertainties and the ideal sliding mode dynamics is the same as that of the optimal LQR for the nominal system. So a global robust optimal sliding mode controller (GROSMC) is realized. Finally, the proposed approach is compared with the LQR by a simulation example. The efficiency and the advantage of the proposed approach are demonstrated successfully. © 2010 ISSN 1881-803X.

Lahr D.J.G.,University of Sao Paulo | Laughinghouse H.D.,Smith College | Oliverio A.M.,Smith College | Gao F.,Ocean University of China | Katz L.A.,Smith College
BioEssays | Year: 2014

Microscopy has revealed tremendous diversity of bacterial and eukaryotic forms. Recent molecular analyses show discordance in estimates of biodiversity between morphological and molecular analyses. Moreover, phylogenetic analyses of the diversity of microbial forms reveal evidence of convergence at scales as deep as interdomain: morphologies shared between bacteria and eukaryotes. Here, we highlight examples of such discordance, focusing on exemplary lineages such as testate amoebae, ciliates, and cyanobacteria. These have long histories of morphological study, enabling deeper analyses on both the molecular and morphological sides. We discuss examples in two main categories: (i) morphologically identical (or highly similar) individuals that are genetically distinct and (ii) morphologically distinct individuals that are genetically the same. We argue that hypotheses about discordance can be tested using the concept of neutral morphologies, or more broadly neutral phenotypes, as a null hypothesis. © 2014 WILEY Periodicals, Inc..

Huang Q.,Beijing Normal University | Yang X.,Brown University | Yang X.,The Ecosystems Center | Gao B.,Beijing Normal University | And 2 more authors.
Remote Sensing | Year: 2014

Since the release of the digital archives of Defense Meteorological Satellite Program Operational Line Scanner (DMSP/OLS) nighttime light data in 1992, a variety of datasets based on this database have been produced and applied to monitor and analyze human activities and natural phenomena. However, differences among these datasets and how they have been applied may potentially confuse researchers working with these data. In this paper, we review the ways in which data from DMSP/OLS nighttime light images have been applied over the past two decades, focusing on differences in data processing, research trends, and the methods used among the different application areas. Five main datasets extracted from this database have led to many studies in various research areas over the last 20 years, and each dataset has its own strengths and limitations. The number of publications based on this database and the diversity of authors and institutions involved have shown promising growth. In addition, researchers have accumulated vast experience retrieving data on the spatial and temporal dynamics of settlement, demographics, and socioeconomic parameters, which are "hotspot" applications in this field. Researchers continue to develop novel ways to extract more information from the DMSP/OLS database and apply the data to interdisciplinary research topics. We believe that DMSP/OLS nighttime light data will play an important role in monitoring and analyzing human activities and natural phenomena from space in the future, particularly over the long term. A transparent platform that encourages data sharing, communication, and discussion of extraction methods and synthesis activities will benefit researchers as well as public and political stakeholders. © 2014 by the authors.

Gao F.,Ocean University of China | Gao F.,Smith College | Katz L.A.,Smith College
Molecular Phylogenetics and Evolution | Year: 2014

Ciliates are a diverse assemblage of eukaryotes that have been the source of many discoveries including self-splicing RNAs, telomeres and trans-splicing. While analyses of ciliate morphology have given rise to robust hypotheses on relatively shallow level relationships, the deeper evolutionary history of ciliates is largely unknown. This is in part because studies to date have focused on only a single locus, small subunit ribosomal DNA (SSU-rDNA). In the present study, we use a taxon-rich strategy based on multiple loci from GenBank and recently completed transcriptomes to assess deep phylogenetic relationships among ciliates. Our phylogenomic data set includes up to 537 taxa, all of which have been sampled for SSU-rDNA and a subset of which have LSU-rDNA and up to 7 protein-coding sequences. Analyses of these data support the bifurcation of ciliates as suggested by SSU-rDNA, with one major clade defined by having somatic macronuclei that divide with intranuclear microtubules (Intramacronucleata) and the other clade containing lineages that either divide their macronuclei with microtubules external to the macronucleus or are unable to divide their macronuclei (Postciliodesmatophora). These multigene phylogenies provide a robust framework for interpreting the evolution of innovations across the ciliate tree of life. © 2013 Elsevier Inc.

Zheng X.D.,Ocean University of China
Genetics and molecular research : GMR | Year: 2012

Owing to their codominant, multiallelic, and highly polymorphic nature, microsatellite markers have been used widely in population genetics and biological resource conservation studies. To investigate the genetic structure of Sepioteuthis lessoniana, we developed 24 microsatellite DNA markers and assessed the polymorphism of each locus in a wild S. lessoniana population. The number of alleles per locus ranged from 4 to 26, and the observed and expected heterozygosities varied from 0.188 to 1.000 and 0.392 to 0.959 with an average of 0.675 and 0.852, respectively. These microsatellite loci will be useful tools in future studies of population genetic structure in this species.

Chen J.,Ocean University of China
MATEC Web of Conferences | Year: 2015

Based on the movement process of throwing and in order to further improve the throwing technique of our country, this paper will first illustrate the main influence factors which will affect the shot distance via the mutual combination of movement equation and geometrical analysis. And then, it will give the equation of the acting force that the throwing athletes have to bear during throwing movement; and will reach the speed relationship between each arthrosis during throwing and batting based on the kinetic analysis of the throwing athletes' arms while throwing. This paper will obtain the momentum relationship of the athletes' each arthrosis by means of rotational inertia analysis; and then establish a restricted particle dynamics equation from the Lagrange equation. The obtained result shows that the momentum of throwing depends on the momentum of the athletes' wrist joints while batting. © Owned by the authors, published by EDP Sciences, 2015.

Chi Z.,Ocean University of China
Chinese Journal of Gastroenterology | Year: 2015

The pathogenesis of irritable bowel syndrome (IBS) is not fully clear, and might be associated with various factors. In 1980s, correlation between ecological imbalance of intestinal flora and IBS was raised. Recently, remarkable efficacy was observed in the treatment of post-infectious IBS (PI-IBS) by re-balancing the intestinal flora with probiotics. Thus it was proved that intestinal flora might play an important role in the pathogenesis of IBS. In this article, the association between ecological imbalance of intestinal flora and IBS as well as the related treatment strategies were reviewed. Copyright © 2015 by Editorial Office of Chinese Journal of Gastroenterology.

Peng W.,Ocean University of China
Genetics and molecular research : GMR | Year: 2012

The sea cucumber (Apostichopus japonicus) is an important item in Asian cuisine. It is currently produced through aquaculture, especially in China, after being overexploited in the wild in the 1990s. We isolated 70 novel polymorphic microsatellite loci using an enrichment-colony hybridization protocol. All loci were characterized in 48 individuals from a natural population in Rongcheng (Shandong, China) using genomic DNA isolated from muscle tissue. The number of alleles ranged from 2 to 17 (mean 7.0), and the observed and expected heterozygosities varied from 0.0010 to 1.0000 and from 0.2125 to 0.9477, respectively. Thirty-one of the 70 loci exhibited departure from Hardy-Weinberg equilibrium. These microsatellite markers should be useful resources for population genetic studies and for molecular marker-assisted breeding of A. japonicus.

Zhang Q.,Ocean University of China
Proceedings. Biological sciences / The Royal Society | Year: 2012

The ciliate subclass Haptoria is a diverse taxon that includes most of the free-living predators in the class Litostomatea. Phylogenetic study of this group was initially conducted using a single molecular marker small-subunit ribosomal RNA (SSU rRNA genes). Multi-gene analysis has been limited because very few other sequences were available. We performed phylogenetic analyses of Haptoria incorporating new SSU rRNA gene sequences from several debated members of the taxon, in particular, the first molecular data from Cyclotrichium. We also provided nine large-subunit ribosomal RNA (LSU rRNA) gene sequences and 10 alpha-tubulin sequences from diverse haptorians, and two possible relatives of controversial haptorians (Plagiopylea, Prostomatea). Phylogenies inferred from the different molecules showed the following: (i) Cyclotrichium and Paraspathidium were clearly separated from the haptorids and even from class Litostomatea, rejecting their high-level taxonomic assignments based on morphology. Both genera branch instead with the classes Plagiopylea, Prostomatea and Oligohymenophora. This raises the possibility that the well-known but phylogenetically problematic cyclotrichiids Mesodinium and Myrionecta may also have affinities here, rather than with litostomes; (ii) the transfer of Trachelotractus to Litostomatea is supported, especially by the analyses of SSU rRNA and LSU rRNA genes, however, Trachelotractus and Chaenea (more uncertainly) generally form the two deepest lineages within litostomes; and (iii) phylogenies of the new molecular markers are consistent with SSU rRNA gene information in recovering order Pleurostomatida as monophyletic. However, Pleurostomatida branches cladistically within order Haptorida, as does subclass Trichostomatia (on the basis of SSU rRNA phylogenies). Our results suggest that the class-level taxonomy of ciliates is still not resolved, and also that a systematic revision of litostomes is required, beginning at high taxonomic levels (taxa currently ranked as subclasses and orders).

Wang H.,CAS Qingdao Institute of Bioenergy and Bioprocess Technology | Zhang C.,CAS Qingdao Institute of Bioenergy and Bioprocess Technology | Liu Z.,CAS Qingdao Institute of Bioenergy and Bioprocess Technology | Wang L.,CAS Qingdao Institute of Bioenergy and Bioprocess Technology | And 7 more authors.
Journal of Materials Chemistry | Year: 2011

In this work, nitrogen-doped graphene nanosheets serving as lithium storage materials are presented. The nitrogen-doped graphene nanosheets were prepared by heat treatment of graphite oxide under an ammonia atmosphere at 800°C for 2 h. Scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy were employed to characterize the prepared product as nitrogen-doped graphene nanosheets with a doping level of ca. 2% nitrogen, where the N binding configuration of the graphene includes 57.4% pyridinic, 35.0% pyrrolic and 7.6% graphitic N atoms. Galvanostatic charge/discharge experiments revealed that these nitrogen-doped graphene nanosheets exhibited a high reversible capacity (900 mA h g-1 at 42 mA g-1 (1/20 C)), excellent rate performance (250 mA h g-1 at a current density of 2.1 A g-1 (2.5 C)), and significantly enhanced cycling stability, which demonstrated nitrogen-doped graphene nanosheets to be a promising candidate for anode materials in high rate lithium-ion batteries. © 2011 The Royal Society of Chemistry.

Zhu M.,Ocean University of China | van Leeuwen P.J.,University of Reading | Amezcua J.,University of Reading
Quarterly Journal of the Royal Meteorological Society | Year: 2016

Filter degeneracy is the main obstacle for the implementation of particle filters in nonlinear high-dimensional models. A new scheme, the implicit equal-weights particle filter (IEWPF), is introduced, in which samples are drawn implicitly from proposal densities with a different covariance for each particle, such that all particle weights are equal by construction. We test and explore the properties of the new scheme using a 1000 dimensional simple linear model and the 1000 dimensional nonlinear Lorenz96 model and compare the performance of the scheme with that of a local ensemble transformed Kalman filter (LETKF). The new scheme is never degenerate and shows good and consistent performance in all experiments. The LETKF has lower root-mean-square errors at observed grid points, but its ensemble spread is too low at unobserved grid points, where the IEWPF performs better. Furthermore, the IEWPF has a consistent spread in all experiments. This new filter opens up a new class of particle filters that, by construction, do not suffer from the curse of dimensionality. © 2016 Royal Meteorological Society.

Sun M.,University of California at Los Angeles | Sun M.,Ocean University of China | Zhong C.,South China University of Technology | Li F.,Qingdao University of Science and Technology | And 2 more authors.
Macromolecules | Year: 2010

Solid-state, white light-emitting electrochemical cells (LECs) based on a fluorene - oxadiazole copolymer have been successfully demonstrated. The copolymer has a π-conjugated backbone consisting of 75 mol % fluorene and 25 mol % 5,5′-diphenyl-2,2′-bi-1,3,4-oxadiazole. 2-(2-(2-M. ethoxyethoxy)ethoxy)ethyl attached on the 9-C of the fluorenes was introduced to promote ionic conductivity necessary for the operation of LECs. The copolymer, synthesized by Suzuki coupling reactions, has a number-average molecular weight of 8700 and polydispersity of 2.41. The LECs were fabricated by spin-coating the copolymer admixed with lithium trifluoromethanesulfonate onto indium - tin oxide (ITO) substrate coated with poly(ethylenedioxythiophene) - poly(styrenesulfonic acid) (PEDOT:PSS). The opposite electrode was vapor evaporated aluminum. The LEC devices showed a white electroluminescence with CIE coordinates of (0.24, 0.31). The emission spectrum consisted of emissions from both the individual polymer chains and excimers. The white LECs are promising for solid-state lighting devices with a simple device structure and low-cost fabrication. © 2010 American Chemical Society.

Zhao D.,Ocean University of China | Zhao D.,North Carolina State University | Xie L.,North Carolina State University
Journal of Oceanography | Year: 2010

The parameter that describes the kinetics of the air-sea exchange of a poorly soluble gas is the gas transfer velocity which is often parameterized as a function of wind speed. Both theoretical and experimental studies suggest that wind waves and their breaking can significantly enhance the gas exchange at the air-sea interface. A relationship between gas transfer velocity and a turbulent Reynolds number related to wind waves and their breaking is proposed based on field observations and drag coefficient formulation. The proposed relationship can be further simplified as a function of the product of wind speed and significant wave height. It is shown that this bi-parameter formula agrees quantitatively with the wind speed based parameterizations under certain wave age conditions. The new gas transfer velocity attains its maximum under fully developed wave fields, in which it is roughly dependent on the square of wind speed. This study provides a practical approach to quantitatively determine the effect of waves on the estimation of air-sea gas fluxes with routine observational data. © 2010 Springer Science+Business Media B.V.

Liu Z.,Bangor University | Liu Z.,Ocean University of China | Liu Z.,Xiamen University
Journal of Physical Oceanography | Year: 2010

The Taylor-Goldstein equation is used to investigate the stability of a baroclinic tidal flow observed in a stratified fjord. The flow is analyzed at hourly intervals when turbulent dissipation measurements were made. The critical gradient Richardson number is often close to the Miles-Howard limit of 0.25, but sometimes it is substantially less. Although during 8 of the 24 periods examined the flow is marginally stable, it is either very stable or very unstable in others. For the unstable flow, the e-folding period of the fastest growing disturbances is 83-455 s, about 46% of the buoyancy period at the levels where the fastest growing disturbances have their maximum amplitude. These disturbances to the flows have wavelengths about 20%-72%of the water depth and have mostly a second-mode structure. Simultaneous measurements of the flow and turbulence allow for testing of the hypothesis that the growth rates of the most unstable disturbances are related to the turbulent dissipation rates. Dissipation is found to depend on the growth rates, but only to a power of about 1.2; there is a stronger (power 1.8) dependence on the buoyancy frequency. © 2010 American Meteorological Society.

Zhao Y.L.,University of Bremen | Zhao Y.L.,Ocean University of China | Koppen S.,University of Bremen | Frauenheim T.,University of Bremen
Journal of Physical Chemistry C | Year: 2011

Theoretical work on amino acid monomers interacting with a silica surface is very important in the field of biomaterials. However, the adsorption of an amino acid monomer on the geminal silanols of silica surfaces has rarely been studied. In this work, we study zwitterionic glycine adsorption on an edingtonite surface covered by geminal silanols using molecular dynamics simulations based on the density functional tight-binding method. By introducing 140 water molecules into the systems, we directly considered the solvent effect. We found that both the amino (NH3 +) and the carboxylic (COO-) groups of glycine can directly form hydrogen bonds with geminal silanols. However, unlike the COO- group, the NH 3 + group cannot be persistently sustained on the surface. Therefore, the dominant configuration is the COO- group pointing toward the surface. Our study not only provides a molecular level understanding of the interactions between inorganic materials and biochemical molecules but also demonstrates a feasible theoretical method on a quantum level for studying these interactions in biomaterial engineering. © 2011 American Chemical Society.

Li Y.,University of Western Australia | Li Y.,Ocean University of China | Waite A.M.,University of Western Australia | Gal G.,Israel Oceanographic And Limnological Research | Hipsey M.R.,University of Western Australia
Ecological Modelling | Year: 2013

The N:P stoichiometry of a water body is one of the most commonly used indicators of its nutrient status and algal growth. However, in a dynamic aquatic ecosystem the N:P stoichiometry of phytoplankton is highly variable and depends on environmental conditions and key microbial interactions that influence their growth, such as grazing pressures and the microbial loop. Here we determine the influence of the nutrient-dependent microbial interactions between zooplankton, phytoplankton and bacteria on the ecological stoichiometry at different trophic levels and how they relate to water column properties. A 1D hydrodynamic-ecological model (DYRESM-CAEDYM) was applied to Lake Kinneret (Israel) for examining how the internal nutrient ratios of several phytoplankton functional groups correlate with nutrient ratios within the water column, and further explore how the microbial loop shapes the patterns of stoichiometry within the food web by testing two microbial loop configurations. The results showed that the average internal N:P ratios of the phytoplankton community followed their total carbon biomass patterns, and that seasonal patterns of simulated dissolved inorganic N to total P (DIN:TP) ratios in the water column were a useful indicator for reflecting the bulk phytoplankton N:P stoichiometry as compared with total N to total P (TN:TP) ratios and dissolved inorganic N to dissolved inorganic P (DIN:DIP) ratios. However, the internal N:P ratio patterns of individual phytoplankton groups did not necessarily correlate with DIN:TP ratio patterns in the water column. This was because different microbial processes regulate nutrient flows to individual phytoplankton groups. Our simulations with the microbial loop highlight the ability of bacteria to regulate phytoplankton stoichiometry. These results provide an improved mechanistic understanding of the food web in aquatic ecosystems. © 2012 Elsevier B.V.

Lin L.,Hefei University of Technology | Lv S.,Hefei University of Technology | Li B.,Ocean University of China
Food Chemistry | Year: 2012

Gelatin extracted from squid (Dosidicus eschrichitii Steenstrup) skin was hydrolysed with pepsin to prepare Angiotensin-I-Converting Enzyme (ACE) inhibitory peptide. The ACE-inhibitory activity was measured by spectrophotometric assay. The hydrolysate was fractionated into three ranges of molecular weight (6 kDa < HSSG-I < 10 kDa, 2 kDa < HSSG-II < 6 kDa, HSSG-III < 2 kDa) using an ultrafiltration unit. The HSSG-III showed the most potent ACE inhibitory activity in vitro with IC50 of 0.33 mg/ml. Renovascular hypertensive rats (RHR) model was made with two-kidney one clip assay, and antihypertensive effects were studied in RHR treated with HSSG-III for 30 days by oral administration. Arterial blood pressure were measured respectively. The HSSG-III remarkably reduced the arterial blood pressure of RHR. These results suggested that hydrolysate of squid skin gelatin obtained by treatment with pepsin was a good source of peptides with ACE-inhibitory activity and had an antihypertensive effect by oral administration. © 2011 Elsevier Ltd. All rights reserved.

Yang H.,Shanghai JiaoTong University | Li H.,Ocean University of China
Science China Technological Sciences | Year: 2011

Steel lazy wave catenary riser (SLWR) has been an attractive choice for deepwater oil field developments. However, fatigue is a critical issue in assessing the feasibility of applying SLWR to large motion vessels such as floating production storage and offloading (FPSO) or semi-submersibles. In this work, the time-domain fatigue analysis of SLWR was adopted for better representing the structural nonlinearity, fluid load nonlinearity and riser-soil nonlinear interaction. The Palmgren-Miner rule was employed for the fatigue life prediction along the riser length. The main purpose of this analysis is to present sensitivity analyses of SLWR fatigue life under various input parameters, which include the structural damping, the hydrodynamic coefficients along the riser, the seabed stiffness, the vessel motions, etc. The analyses indicated the strong dependence of the riser fatigue life on these parameters. The results can help designers to understand the dynamic behavior of the SLWR and provide guidance for selection of some critical parameters that are used in the fatigue design. © 2011 Science China Press and Springer-Verlag Berlin Heidelberg.

Zhang B.-L.,China Jiliang University | Hu. Y.-H.,China Jiliang University | Tang G.-Y.,Ocean University of China
Nonlinear Dynamics | Year: 2012

This paper is concerned with the stabilization control for the offshore steel jacket platforms subject to wave-induced force. Two state feedback stabilization control schemes are proposed to reduce the vibration amplitudes of the systems. One scheme is that for the systems without actuator time-delay, a state feedback controller is designed. Compared with the nonlinear controller, both the control force and the vibration amplitudes of the systems under the state feedback controller are much reduced; and compared with the dynamic output feedback controller and the integral sliding mode controller, the required control force under the state feedback controller are significantly reduced. The other scheme is that based on the integral inequality approach, a delay-dependent state feedback controller, which can be solved by using the cone complementarity algorithm, is developed to control the systems with actuator time-delays. Compared with the state feedback controller, the delay-dependent state feedback controller is less conservative with actuator time-delays. In addition, it is capable of improving the control performance of the offshore platforms significantly, which are illustrated by simulation results. © Springer Science+Business Media B.V. 2012.

Liu Y.,Ocean University of China | Li Y.-C.,Dalian University of Technology | Teng B.,Dalian University of Technology
Journal of Engineering Mathematics | Year: 2012

This study examines the interaction of obliquely incident waves with a breakwater consisting of an infinite array of uniform multi-chamber perforated caissons with partition walls. Based on the linear potential theory, an analytical solution of the problem is developed by means of the matched eigenfunction expansion method. The periodicities of the breakwater and the incident waves are both incorporated into the solution. Several limiting cases are also examined to validate the newly developed solution. Three parameters of engineering interests, the reflection coefficient, the dimensionless total wave force in the normal direction of the breakwater and the dimensionless total wave force acting on the partition walls, are calculated and carefully examined. This study may give a better understanding of the hydrodynamic performance of multi-chamber perforated caissons. Some useful results are also presented to practical engineering. © 2011 Springer Science+Business Media B.V.

Sun S.,Qingdao University of Science and Technology | Chang X.,Ocean University of China | Li Z.,Qingdao University of Science and Technology
Materials Research Bulletin | Year: 2010

Single-crystalline non-stoichiometric tungsten oxide nanowires were initially prepared using a simple solvothermal method. High resolution transmission electron microscopy (HRTEM) investigations indicate that the tungsten oxide nanowires exhibit various crystal defects, including stacking faults, dislocations, and vacancies. A possible defect-induced mechanism was proposed to account for the temperature-dependent morphological evolution of the tungsten oxide nanowires under thermal processing. Due to the high specific surface areas and non-stoichiometric crystal structure, the original tungsten oxide nanowires were highly sensitive to ppm level ethanol at room temperature. Thermal treatment under dry air condition was found to deteriorate the selectivity of room-temperature tungsten oxide sensors, and 400 °C may be considered as the top temperature limit in sensor applications for the solvothermally-prepared nanowires. The photoluminescence (PL) characteristics of tungsten oxide nanowires were also strongly influenced by thermal treatment. © 2010 Elsevier Ltd. All rights reserved.

Zhang B.,Ocean University of China
Zhejiang da xue xue bao. Yi xue ban = Journal of Zhejiang University. Medical sciences | Year: 2010

To investigate the effect of sea cucumber cerebroside (SCC) on the lipid metabolism in rats with orotic acid-induced fatty liver. The non-alcoholic fatty liver disease (NAFLD) model was established by adding orotic acid to the diets in rats. The rats were randomly assigned to four groups:control group, NAFLD group, NAFLD + low SCC group and NAFLD + high SCC group. After 10 days of feeding, the serum and hepatic lipid concentrations and the aminopherase activities were measured; the composition of hepatic fatty acids was also analyzed. The serum TC and TG levels reduced significantly in the NAFLD group as compared with the controls (P<0.05), while the sea cucumber cereborside feeding raised the serum lipid concentrations (P<0.05). The hepatic TC and TG levels dramatically increased in the NAFLD group in comparison with the controls (P<0.05, P<0.01), while the hepatic lipid accumulations decreased in both SCC groups (P<0.05, P<0.01). The ALT and AST activities in the NAFLD group increased markedly when compared with the controls (P<0.05, P <0.01), while the sea cucumber cerebroside feeding attenuated the hepatic injury levels (P<0.05, P<0.01). Compared with the control group, the stearoyl-CoA desaturase (SCD) activity increased significantly in the NAFLD group (P<0.05), but decreased in SCC groups (P<0.05). Sea cucumber cerebroside can attenuate the rat fatty liver induced by orotic acid.

Dong B.,China National Petroleum Corporation | He B.-l.,Ocean University of China | Chai Y.-m.,China National Petroleum Corporation | Liu C.-g.,China National Petroleum Corporation
Materials Chemistry and Physics | Year: 2010

Pt nanoclusters/titanium dioxide nanotubes (nano-Pt/TiO2-NTs) composites were successfully prepared using TiO2-NTs as supports. The structure and morphology of the resulting composites were characterized. The results showed Pt nanoclusters with the size ranging from 15 to 20 nm were well dispersed on the surface of TiO2-NTs. The electrocatalytic properties of nano-Pt/TiO2-NTs composites for hydrazine oxidation were firstly investigated on the corresponding modified glassy carbon electrode by cyclic voltammetry (CV). The resulting nano-Pt/TiO2-NTs composites showed excellent electrocatalytic activity. This may be attributed to the small particle size and good dispersion of Pt nanoclusters as well as the unique properties of TiO2-NTs supports. In addition, the mechanism of hydrazine electrochemical oxidation on Pt/TiO2-NTs are also investigated. The results imply that TiO2-NTs are the promising supporting materials for noble catalysts with high activity. © 2009 Elsevier B.V. All rights reserved.

Chen S.,Ocean University of China | Chen S.,CAS Institute of Microbiology | Guo L.,CAS Institute of Microbiology
Mycotaxon | Year: 2011

A new species, Septobasidium sichuanense, is described. It was collected from Sichuan Province, China. © 2011. Mycotaxon, Ltd.

Du X.,Ocean University of China | Du X.,Cooperative Institute for Marine Resource Studies | Du X.,CAS East China Sea Fisheries Research Institute | Peterson W.T.,National Oceanic and Atmospheric Administration
Estuaries and Coasts | Year: 2014

Coastal upwelling in the northern California Current varies seasonally, with downwelling in winter and upwelling in summer, resulting in pronounced variability in hydrography, nutrients, phytoplankton biomass, and species composition. Winter was characterized by moderate concentrations of nitrate and silicate (averages of 10 and 18 μM, respectively) and low concentrations of chlorophyll a (Chl a). During the upwelling season, concentrations of the same nutrients ranged from near 0 μM to approximately 27 and 43 μM and Chl a 0.5 < x < 15 μg L-1. During autumn, upwelling weakened and nutrient concentrations were reduced, but large phytoplankton blooms continued to occur. Variations in hydrography, nutrients, and phytoplankton also occurred within the upwelling season due to alternation of the winds between northerly (active upwelling) and southerly (relaxation of upwelling), on a 5- to 10-day time scale. Eleven blooms were observed, most of which occurred near the end of active upwelling events and during relaxation of upwelling. Nonmetric multidimensional scaling ordination of species composition of the microplankton revealed four distinct communities: a winter community, early upwelling and late upwelling season communities, and an autumn community. Diatoms (Asterionellopsis glacialis, Eucampia zodiacus, and several Chaetoceros, Thalassiosira, and Pseudo-nitzschia species) dominated early in the upwelling season, averaging 80 % of the phytoplankton biomass, and dinoflagellates dominated near the end of the upwelling season, averaging 68 % of the phytoplankton biomass. Dinoflagellates formed two monospecific blooms-Prorocentrum gracile in late summer and Akashiwo sanguinea in autumn. Changes in community composition were correlated with bottom temperature and salinity (representing seasonal variability) and sea surface salinity (representing within-season event-scale variability in upwelling). © 2013 Coastal and Estuarine Research Federation (outside the USA).

Bai Y.,University of Massachusetts Amherst | Lin D.,University of Massachusetts Amherst | Lin D.,Zhejiang University | Wu F.,Chinese Research Academy of Environmental Sciences | And 2 more authors.
Chemosphere | Year: 2010

Surfactants can enhance the stabilization of carbon nanotubes (CNTs) in water through their adsorption, thus affecting the environmental behavior and application of CNTs. However, the quantitative relationship between adsorption and stabilization and the role of the surfactant structure in the surfactant-CNT interactions are largely unknown. Therefore, Triton X-series surfactants with a same hydrophobic functional group (4-(1,1,3,3-tetramethylbutyl)-phenyl) and different hydrophilic polyethoxyl chain lengths were selected to investigate their adsorption onto CNTs and their ability to stabilize CNT suspensions. Adsorption data were fitted well by Langmuir equation, indicating monolayer coverage on CNTs. Adsorption capacities of the surfactants increased with decreasing hydrophilic chain length: Triton-305 < Triton-165 < Triton-114 < Triton-100. Electrostatic interaction and hydrogen bond could be excluded as the main mechanism because adsorption was not significantly affected by pH change. Hydrophobic and π-π interactions between the surfactants and CNTs were the dominant mechanism for their adsorption. CNT suspension data were well fitted to a nonlinear equation with a similar form to the Langmuir equation. Suspended CNT amounts in water were positively related to the adsorption capacities of the surfactants, but negatively with the hydrophilic fraction ratio of the X-series surfactants. © 2010 Elsevier Ltd. All rights reserved.

Chang C.-Y.,Chia Nan University of Pharmacy and Science | Tanong K.,Chia Nan University of Pharmacy and Science | Xu J.,Ocean University of China | Shon H.,University of Technology, Sydney
Bioresource Technology | Year: 2011

A two-stage aerobic membrane bioreactor (MBR) system for treating acrylonitrile butadiene styrene (ABS) resin wastewater was carried out in this study to evaluate the system performance on nitrification. The results showed that nitrification of the aerobic MBR system was significant and the highest TKN removal of approximately 90% was obtained at hydraulic retention time (HRT) 18. h. In addition, the result of nitrogen mass balance revealed that the percentage of TN removal due to denitrification was in the range of 8.7-19.8%. Microbial community analysis based on 16s rDNA molecular approach indicated that the dominant ammonia oxidizing bacteria (AOB) group in the system was a β-class ammonia oxidizer which was identified as uncultured sludge bacterium (AF234732). A heterotrophic aerobic denitrifier identified as Thauera mechernichensis was found in the system. The results indicated that a sole aerobic MBR system for simultaneous removals of carbon and nitrogen can be designed and operated for neglect with an anaerobic unit. © 2010 Elsevier Ltd.

Liu X.,Tongji University | Wen Z.,Jiangxi Normal University | Wu D.,Tongji University | Wang H.,Ocean University of China | And 2 more authors.
Journal of Materials Chemistry A | Year: 2014

Herein, we describe a supramolecular approach to synthesize tough ionogels through self-initiated ultraviolet polymerization. The prepared ionogel can be used as the integrated electrolyte and separator in the all-solid supercapacitor. The electrochemical performance can be tuned by the temperature, and a higher value can be achieved at higher temperature. This journal is © the Partner Organisations 2014.

Wu S.,Ocean University of China
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2011

Lidar detects atmospheric parameters by transmitting laser pulse to the atmosphere and receiving the backscattering signals from molecules and aerosol particles. Because of the small backscattering cross section, lidar usually uses the high sensitive photomultiplier and avalanche photodiode as detector and uses photon counting technology for collection of weak backscatter signals. Photon Counting enables the capturing of extremely weak lidar return from long distance throughout dark background by a long time accumulation. Because of the strong solar background, the signal-to-noise ratio of lidar in the daytime could be greatly restricted, especially for the lidar operating at visible band where solar background is prominent. Narrow band-pass filters must therefore be installed in order to isolate solar background noise at wavelengths close to that of the lidar receiving channel, whereas the background light in superposition with signal spectrum limits an effective margin for SNR improvement. This work propose a high spectral resolution lidar prototype operating at the Fraunhofer lines, the invisible band of solar spectrum, to achieve photon counting under intense solar background. The laser transmitter is an optical parametric oscillator pump by 355 nm Nd:YAG laser and is tuned to the dark line by the Magnesium atom of the solar atmosphere by which nearly 90% of solar radiation is absorbed. The prototype provides some theoretical references for optimized design of photon counting lidar in visible band with the comparable SNR at night, which may contribute to the research on diurnal variation of atmosphere and to the operational observation of lidar. © 2011 SPIE.

Wen W.J.,Ocean University of China
Applied Mechanics and Materials | Year: 2014

Abstract. ETL refers to the process of data extracting, transformation and loading and is deemed as a critical step in ensuring the quality, data specification and standardization of marine environmental data. Marine data, due to their complication, field diversity and huge volume, still remain decentralized, polyphyletic and isomerous with different semantics and hence far from being able to provide effective data sources for decision making. ETL enables the construction of marine environmental data warehouse in the form of cleaning, transformation, integration, loading and periodic updating of basic marine data warehouse. The paper presents a research on rules for cleaning, transformation and integration of marine data, based on which original ETL system of marine environmental data warehouse is so designed and developed. The system further guarantees data quality and correctness in analysis and decision-making based on marine environmental data in the future. © (2014) Trans Tech Publications, Switzerland.

Zhao Y.-G.,Ocean University of China | Zhao Y.-G.,Harbin Institute of Technology | Wang A.-J.,Harbin Institute of Technology | Ren N.-Q.,Harbin Institute of Technology
Bioresource Technology | Year: 2010

The effect of different carbon sources on the starting-up duration of sulfidogenic bioreactor and corresponding bacterial communities were investigated. The bioreactor starting-up duration was closely dependent on the complexity and availability of the carbon sources. 16S rRNA gene diversity of climax bacterial communities developed in each bioreactor had an increasing tendency for the carbon resource of lactate, acetate/ethanol, glucose and molasses. At the steady stage of bioreactors, the molasses-fed bacterial community pattern grouped with that of glucose-fed and acetate/ethanol-fed grouped with that of lactate-fed, both of which separated each other and departed further from the seed sludge. The present study concludes that utilization of simple carbon sources that are readily utilized by sulfate-reducing bacteria (SRB) can not only increase the fraction of SRB and thus improve sulfate removal efficiency, but also shorten the starting-up duration. © 2009 Elsevier Ltd. All rights reserved.

It has been suggested that statistical parsimony network analysis could be used to get an indication of species represented in a set of nucleotide data, and the approach has been used to discuss species boundaries in some taxa. Based on 635 base pairs of the mitochondrial protein-coding gene cytochrome c oxidase I (COI), we analyzed 152 nemertean specimens using statistical parsimony network analysis with the connection probability set to 95%. The analysis revealed 15 distinct networks together with seven singletons. Statistical parsimony yielded three networks supporting the species status of Cephalothrix rufifrons, C. major and C. spiralis as they currently have been delineated by morphological characters and geographical location. Many other networks contained haplotypes from nearby geographical locations. Cladistic structure by maximum likelihood analysis overall supported the network analysis, but indicated a false positive result where subnetworks should have been connected into one network/species. This probably is caused by undersampling of the intraspecific haplotype diversity. Statistical parsimony network analysis provides a rapid and useful tool for detecting possible undescribed/cryptic species among cephalotrichid nemerteans based on COI gene. It should be combined with phylogenetic analysis to get indications of false positive results, i.e., subnetworks that would have been connected with more extensive haplotype sampling.

Chen G.,Ocean University of China | Chen H.,Imperial College London
Journal of Climate | Year: 2015

Using the newly available decade-long Argo data for the period 2004-13, a detailed study is carried out on deriving four-dimensional (4D) modality of sea temperature in the upper ocean with emphasis on its interannual variability in terms of amplitude, phase, and periodicity. Three principal modes with central periodicities at 19.2, 33.8, and 50.3 months have been identified, and their relationship with El Niño-Southern Oscillation (ENSO) is investigated, yielding a number of useful results and conclusions: 1) A striking tick-shaped pipe-like feature of interannual variability maxima, which is named the "Niño pipe" in this paper, has been revealed within the 10°S-10°N upper Pacific Ocean. 2) The pipe core extends downward from ~50 m at 130°E to ~250 m near the date line before tilting upward to the sea surface at about 275°E, coinciding nicely with the pathway of the Pacific equatorial undercurrent (EUC). 3) The double-peak zonal modality pattern of the Niño pipe in the upper Pacific is echoed in the subsurface Atlantic and Indian Oceans through Walker circulation, while its single-peak meridional modality pattern is mirrored in the subsurface North and South Pacific through Hadley circulation. 4) A coherent three-peak modal structure implies a strong coupling between sea level variability at the surface and sea temperature variability around the thermocline. Accumulating evidence suggests that Rossby/Kelvin wave dynamics in tandem with EUC-based thermocline dynamics are the main mechanisms of the three-mode Niño pipe in ENSO cycles. © 2015 American Meteorological Society.

Zhang D.-L.,CAS Qingdao Institute of Oceanology | Zhang D.-L.,University of Chinese Academy of Sciences | Wang W.,Ocean University of China | Li Y.,CAS Qingdao Institute of Oceanology
Corrosion Science | Year: 2010

The local electrochemical properties of anodic metal within a zinc/steel couple immersed in seawater was studied via an electrode array composed of zinc and mild steel wire sensors. It showed that the potential and current density distribution of zinc wires were inhomogeneous, and the main anodic area moved from the zinc wires adjacent to the steel wires and even further away. Also, some zinc wires behaved as secondary cathodes. The observed electrochemical inhomogeneity was attributed to the variation of distances between the zinc and mild steel wire sensors over the electrode array as well as their surface electrochemical status. © 2009 Elsevier Ltd. All rights reserved.

Liu F.,CAS Institute of Software | Liu F.,University of Chinese Academy of Sciences | Wu C.,CAS Institute of Software | Lin X.,Ocean University of China
Information Processing Letters | Year: 2010

In this paper, some of the known definitions of the contrast of the Visual Cryptography Scheme (VCS) are shown to be inappropriate, and a new definition of the contrast based on our observations is proposed. It is also shown how our new definition of the contrast agreed with our observations. © 2010 Elsevier B.V. All rights reserved.

Yang S.T.,Ocean University of China | Hu X.Z.,University of Western Australia | Wu Z.M.,Dalian University of Technology
Engineering Fracture Mechanics | Year: 2011

The maximum fracture load of a notched concrete beam has been related to the local fracture energy at the cohesive crack tip region analytically in this paper, and then the correlation between the size effects on the maximum fracture loads and the RILEM specific fracture energy is established. Two extreme conditions have been established, namely zero crack-tip bridging with zero local fracture energy and maximum crack-tip bridging with the maximum size-independent fracture energy. It is concluded that the local fracture energy at the crack tip region indeed varies with the initial crack length and the size of specimen. The tri-linear model for the local fracture energy distribution is confirmed by using the proposed simple analytical solution. © 2011 Elsevier Ltd.

Hu R.,Ocean University of China | Wei M.,Jiaozhou Meteorological Bureau
Advances in Atmospheric Sciences | Year: 2013

The intraseasonal oscillation (ISO; 14-97-day periods) of temperature in the upper 2000 m of the global ocean was studied based on Argo observations from 2003-2008. It is shown that near the surface the ISO existed mainly in a band east of 60°E, between 10°S and 10°N, and the region around the Antarctic Circumpolar Current (ACC). At other levels analyzed, the ISOs also existed in the regions of the Kuroshio, the Gulf Stream, the Indonesian throughflow, the Somalia current, and the subtropical countercurrent (STCC) of the North Pacific. The intraseasonal signals can be seen even at depths of about 2000 m in some regions of the global ocean. The largest amplitude of ISO appeared at the thermocline of the equatorial Pacific, Atlantic and Indian Ocean, with maximum standard deviation (STD) exceeding 1.2°C. The ACC, the Kuroshio, and the Gulf Stream regions all exhibited large STD for all levels analyzed. Especially at 1000 m, the largest STD appeared in the south and southeast of South Africa-a part of the ACC, with a maximum value that reached 0.5°C. The ratios of the intraseasonal temperature variance to the total variance at 1000 m and at the equator indicated that, in a considerable part of the global deep ocean, the ISO was dominant in the variations of temperature, since such a ratio exceeded even 50% there. A case study also confirmed the existence of the ISO in the deep ocean. These results provide useful information for the design of field observations in the global ocean. Analysis and discussion are also given for the mechanism of the ISO. © 2013 Chinese National Committee for International Association of Meteorology and Atmospheric Sciences, Institute of Atmospheric Physics, Science Press and Springer-Verlag Berlin Heidelberg.

Su N.,East China Normal University | Du J.,East China Normal University | Moore W.S.,University of South Carolina | Liu S.,Ocean University of China | Zhang J.,East China Normal University
Science of the Total Environment | Year: 2011

The nutrient concentrations and stoichiometry in a coastal bay/estuary are strongly influenced by the direct riverine discharge and the submarine groundwater discharge (SGD). To estimate the fluxes of submarine groundwater discharge into the Bamen Bay (BB) and the Wanquan River Estuary (WQ) of eastern Hainan Island, China, the naturally occurring radium isotope ( 226Ra) was measured in water samples collected in the bay/estuary in August 2007 and 2008. Based on the distribution of 226Ra in the surface water, a 3-end-member mixing model was used to estimate the relative contributions of the sources to these systems. Flushing times of 3.9±2.7 and 12.9±9.3days were estimated for the BB and WQ, respectively, to calculate the radium fluxes for each system. Based on the radium fluxes from groundwater discharge and the Ra isotopic compositions in the groundwater samples, the estimated SGD fluxes were 3.4±5.0m 3s -1 in the BB and 0.08±0.08m 3s -1 in the WQ, or 16% and 0.06%, respectively, of the local river discharge. Using this information, the nutrient fluxes from the submarine groundwater discharge seeping into the BB and WQ regions were estimated. In comparison with the nutrient fluxes from the local rivers, the SGD-derived nutrient fluxes played a vital role in controlling the nutrient budgets and stoichiometry in the study area, especially in the BB. © 2011 Elsevier B.V.

Zhang L.,Atmospheric and Oceanic science ProgramPrinceton UniversityPrinceton | Zhao C.,Ocean University of China
Journal of Advances in Modeling Earth Systems | Year: 2015

Almost all of CMIP5 climate models show cold SST biases in the extratropical North Atlantic (ENA) and tropical North Atlantic (TNA) as well as in the North Pacific which are commonly linked with the weak simulated Atlantic meridional overturning circulation (AMOC). A weak AMOC and its associated reduced northward oceanic heat transport are associated with a cooling of the ENA Ocean, whereas the TNA cooling is attributable to both weak AMOC and surface heat flux. The cold biases in the ENA and TNA have remote impacts on the SST bias in the North Pacific. Here we use coupled ocean-atmosphere model experiments to show the mechanisms and pathways by which the ENA and TNA affect the North Pacific. The model simulations demonstrate that the cooling SST bias in the North Pacific is largely due to the remote effect of the cooling SST bias in the ENA, while the remote impact of the TNA cooling SST bias is of secondary importance. The ENA cooling bias triggers the circumglobal teleconnection via the Northern Hemisphere annular mode, producing a strengthening of the Aleutian low, an enhancement of the southward Ekman and Oyashio cold advection, and thus a cooling SST in the North Pacific. In contrast, the TNA cooling produces a surface high extending to the eastern tropical North Pacific, inducing the northeasterly wind anomalies north, northerly cross-equatorial wind anomalies, and northwesterly wind anomalies south of the equator. This C-shape wind anomaly pattern generates an SST warming in the tropical southeastern Pacific, which eventually leads to an SST warming in the tropical central and western Pacific by the wind-evaporation-SST feedback. The tropical Pacific warming in turn leads to an SST cooling in the North Pacific by the Pacific North American teleconnection pattern. © 2015. The Authors.

Stopa J.E.,French National Center for Scientific Research | Ardhuin F.,French National Center for Scientific Research | Jiang H.,Ocean University of China | Chapron B.,French National Center for Scientific Research | Collard F.,Ocean Data Laboratory Plouzane France
Geophysical Research Letters | Year: 2016

Swells are found in all oceans and strongly influence the wave climate and air-sea processes. The poorly known swell dissipation is the largest source of error in wave forecasts and hindcasts. We use synthetic aperture radar data to identify swell sources and trajectories, allowing a statistically significant estimation of swell dissipation. We mined the entire Envisat mission 2003-2012 to find suitable storms with swells (13

Wang H.,University of California at San Diego | Xie S.-P.,University of California at San Diego | Tokinaga H.,Kyoto University | Liu Q.,Ocean University of China | Kosaka Y.,Tokyo University of Technology
Geophysical Research Letters | Year: 2016

Anthropogenic aerosols are a major driver of the twetieth century climate change. In climate models, the aerosol forcing, larger in the Northern than Southern Hemispheres, induces an interhemispheric Hadley circulation. In support of the model result, we detected a robust change in the zonal mean cross-equatorial wind over the past 60years from ship observations and reanalyses, accompanied by physically consistent changes in atmospheric pressure and marine cloud cover. Single-forcing experiments indicate that the observed change in cross-equatorial wind is a fingerprint of aerosol forcing. This zonal mean mode follows the evolution of global aerosol forcing that is distinct from regional changes in the Atlantic sector. Atmospheric simulations successfully reproduce this interhemispheric mode, indicating the importance of sea surface temperature mediation in response to anthropogenic aerosol forcing. As societies awaken to reduce aerosol emissions, a phase reversal of this interhemispheric mode is expected in the 21st century. ©2016. American Geophysical Union.

Liu X.,Ocean University of China | Zhao D.,Tohoku University
Journal of Geophysical Research: Solid Earth | Year: 2016

We present 3-D images of azimuthal anisotropy tomography of the crust and upper mantle of the Japan subduction zone, which are determined using a large number of high-quality P and S wave arrival time data of local earthquakes and teleseismic events. A tomographic method for P wave velocity azimuthal anisotropy is modified and extended to invert S wave traveltimes for 3-D S wave velocity azimuthal anisotropy. A joint inversion of the P and S wave data is conducted to constrain the 3-D azimuthal anisotropy of the Japan subduction zone. Our results show that the subducting Pacific and Philippine Sea (PHS) slabs exhibit mainly trench-parallel fast-velocity directions (FVDs), which may reflect frozen-in lattice-preferred orientation of aligned anisotropic minerals formed at the mid-ocean ridge as well as shape-preferred orientation such as normal faults produced at the outer-rise area near the trench axis. Trench-normal FVDs are generally revealed in the mantle wedge, which may reflect corner flows in the mantle wedge due to the plate subduction and dehydration. Trench-normal FVDs are also visible in the subslab mantle, which may reflect the subducting asthenosphere underlying the slabs. Our results also reveal toroidal mantle flows in and around a window (hole) in the PHS slab beneath SW Japan, suggesting that the occurrence of the PHS slab window may have caused a complex flow pattern in the mantle wedge above the Pacific slab. © 2016. American Geophysical Union. All Rights Reserved.

Shizhe T.,Ocean University of China
Microsystem Technologies | Year: 2014

Biomimetics is a promising field of research in which natural processes and structures are transferred to technical applications. The lateral line is a critical component of the fish sensory system and plays an important role in many behaviors by providing hydrodynamic information about the surrounding fluid. It is believed that the artificial lateral line flow sensors (ALLFS) are advantageous for underwater applications. This paper reviews the morphology and biophysics of the lateral line, especially theoretical models of lateral line, including biomechanical model, frequency response and time domain response of lateral line. Also, this paper reviews some efforts to mimic lateral line system in recent years. In order to capture the recent research status, this paper reviews the design and fabrication of ALLFS based on different sensing principles. Further researches to develop ALLFS and their underwater applications are also discussed in this paper. © Springer-Verlag Berlin Heidelberg 2014.

Nishioka H.,Nagoya University | Liang X.,Nagoya University | Liang X.,Ocean University of China | Kato T.,Nagoya University | Asanuma H.,Nagoya University
Angewandte Chemie - International Edition | Year: 2012

DNA seesaw: Photoswitchable azobenzenecarboxylic acid 1 reversibly photoisomerizes between the trans form and the thermally stable cis form upon irradiation with visible light. A photon-fueled DNA nanodevice that moves like a seesaw in response to irradiation with different wavelengths of light was made by modifying DNA oligonucleotides with a combination of 1 and a conventional azobenzene (see picture). Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Yang P.,Yunnan Normal University | Tang Q.,Ocean University of China
Electrochimica Acta | Year: 2016

Bifacial dye-sensitized solar cell (DSSC) is a promising solution to reduce the cost of photovoltaic conversion. We present here the experimental realization of bifacial quasi-solid-state DSSC from a TiO2 photoanode, a semitransparent gel electrolyte, and a Ti grid supported metal selenide (MSe, M = Co, Ni, Ru) counter electrode (CE). In comparison with front efficiency of 4.87% and rear efficiency of 1.19% for Ti grid supported Pt based DSSC, the efficiencies are enhanced to 6.51% and 1.84% on the solar cell with cost-effective Ti grid supported RuSe CE. The preliminary results demonstrate that this architecture is promising in realizing cost-effective bifacial quasi-solid-state DSSCs without sacrificing photovoltaic performances. © 2015 Elsevier Ltd. All rights reserved.

Chen J.,Ocean University of China
Dong wu xue yan jiu = Zoological research / "Dong wu xue yan jiu" bian ji wei yuan hui bian ji | Year: 2010

DNA barcoding has exhibited charming effectiveness in species diagnosis, but some studies suggested the proportion of taxa that cannot be barcode-distinguished was still high. In the present study, the efficiency of the DNA barcoding for delimiting species of subfamily Tapetinae along the coast of China was tested. Fifty one original COI sequences of 11 species in five genera were analyzed. Among these sequences, 43 haplotypes were identified. Saturation plots generated for DNA barcode revealed that transitions became saturated after 10% to 15% sequence divergence. However, transversions were not saturated. Excluding Ruditapes variegata haplotype Hap33 that might be the result of a hybridization event, our finding showed that K2P-distances between conspecific sequences varied from 0% to 2.02% (0.46% on average), distances between congeneric sequences were from 17.21% to 32.24% (24.96% on average), and all conspecifics clustered together in the phylogentic trees. The proportion of individuals that can be distinguished by DNA barcoding was approximately 98% among 51 individuals analyzed in this study. Thus, the results evidenced that subfamily Tapetinae species can be efficiently identified through the use of DNA barcoding.

Wu M.,University of Hong Kong | Zhao G.,University of Hong Kong | Sun M.,University of Hong Kong | Li S.,Ocean University of China | And 2 more authors.
Lithos | Year: 2013

As an important component of the Western Shandong Complex in the Eastern Block of the North China Craton, the Yishui Terrane consists of Neoarchean high-grade supracrustal rocks, granitoid gneisses and charnockites. LA-ICP-MS zircon UPb dating and Hf isotopic analyses on these lithologies have been carried out and the results provide new insights into the Neoarchean crustal evolution of the Eastern Block of the North China Craton. New zircon dating results reveal that the magmatic precursors of the supracrustal metapelites and granitoid gneisses were generated at 2.54-2.53Ga and 2.57-2.55Ga, respectively, and the charnockites were emplaced contemporaneously around 2.56-2.53Ga. Single metamorphic zircon grains and overgrowth rims from these rocks document consistent metamorphic ages at ~2.50Ga, suggesting that the Yishui Terrane experienced a high-grade metamorphic event at the end of the Neoarchean. Detrital zircons from pelitic gneisses yield 207Pb/206Pb ages of 2.89-2.65Ga, with a major age peak at ~2.53Ga and a subordinate age peak at ~2.70Ga, implying that the sedimentary protoliths of the pelitic gneisses may have been sourced from ~2.53Ga rocks in the Yishui Terrane and ~2.70Ga rocks in the adjacent Luxi Granite-Greenstone Terrane. Hf isotopic compositions show that the Neoarchean magmatic zircons have positive εHf(t) values ranging from +1.4 to +7.8 and depleted mantle model ages of 2.92-2.60Ga with a prominent peak at 2.8-2.7Ga, suggesting that the Neoarchean crust was derived mainly from juvenile sources and partly from the recycling of old continental crust in the Yishui area. Combined with previous data from the adjacent Luxi Granite-Greenstone Terrane and other complexes in the Eastern Block, it is concluded that the Neoarchean was an important period of crust accretion in the Eastern Block of the North China Craton. © 2013 Elsevier B.V.

Wang J.,Ocean University of China
Wei sheng yan jiu = Journal of hygiene research | Year: 2011

To evaluate the immunomodulatory effect of a mixture of A. japonicus and C. militaris on immune functions of immunocompromized mouse model. Fifty Balb/c mice were randomly selected and assigned into five groups (ten animals per group): a normal control group, a model control group, a positive control group and low and high dose groups. A mixture of A. japonicus and Cordyceps militaris was administered orally every day to mice in dose groups at a dosage of 60 and 120 mg/kg x bw respectively. Mice in positive control group were given orally with levamisole hydrochloride at a dosage of 20 mg/kg x bw. Mice in normal and model control groups were administered with 0.9% NaCl solution as placebo. All agents were administered once a day for 28 days. On the 21st day, all mice except that in the normal group were injected hypodermally with hydrocortisone at a dosage of 22.5 mg/kg x bw once a day for 7 days to generate a immunocompromised animal model. The mice were deprived of food for 12h after the last administration, and the delayed type hypersensitivity (DTH), hemolysin, antibody forming cells, the clearance of carbon particles in macrophages, the production of cytokine IFN-gamma and IL-4 were measured respectively. The DTH level (P < 0.01), hemolysin content (P < 0.01) and the number of antibody forming cells (P < 0.05), carbon particle clearance index (P < 0.01) in immunocompromised mice administered with the mixture of A. japonicus and C. militaris were increased obviously. At the same time, the mixture could also enhance IFN-gamma (P < 0.01) content and reduce IL-4 (P < 0.05) content. Both the specific and non-specific immune function in immunocompromised mice could be stimulated by the mixture of A. japonicus and C. militaris.

Guan H.,Ocean University of China | Wang X.,Japan International Center for Materials Nanoarchitectonics | Li H.,Japan Advanced Institute of Industrial Technology | Zhi C.,Japan International Center for Materials Nanoarchitectonics | And 3 more authors.
Chemical Communications | Year: 2012

Pure-phase CoO octahedral nanocages were successfully fabricated by a novel simple method. The coordination etching agents play key roles in the formation of these non-spherical hollow structures. When tested as anode materials in lithium ion batteries (LIBs), these nanocages showed excellent cycling performance, good rate capability and enhanced lithium storage capacity. © 2012 The Royal Society of Chemistry.

Bai J.,Ocean University of China
International Journal of Marine and Coastal Law | Year: 2015

In the context of the melting icecap and the growing shipping activity in the Arctic, the International Maritime Organization (imo) spent several years preparing polar navigation rules aimed at providing appropriate safety and environmental protection standards. The rules underwent several transformations before emerging as the binding International Code for Ships Operating in Polar Waters (Polar Code). The Polar Code is expected to enter into force on 1 January 2017. This paper examines the formation and development of the Polar Code and its principles and provisions, expounds upon the unique characteristics of the Code, and discusses expected future practices. © Koninklijke Brill NV, Leiden, 2015.

Huang P.,CAS Institute of Atmospheric Physics | Xie S.-P.,University of California at San Diego | Xie S.-P.,Ocean University of China | Xie S.-P.,University of Hawaii at Manoa | And 3 more authors.
Nature Geoscience | Year: 2013

Tropical convection is an important factor in regional climate variability and change around the globe. The response of regional precipitation to global warming is spatially variable, and state-of-the-art model projections suffer large uncertainties in the geographic distribution of precipitation changes. Two views exist regarding tropical rainfall change: one predicts increased rainfall in presently rainy regions (wet-get-wetter), and the other suggests increased rainfall where the rise in sea surface temperature exceeds the mean surface warming in the tropics (warmer-get-wetter). Here we analyse simulations with 18 models from the Coupled Model Intercomparison Project (CMIP5), and present a unifying view for seasonal rainfall change. We find that the pattern of ocean warming induces ascending atmospheric flow at the Equator and subsidence on the flanks, anchoring a band of annual mean rainfall increase near the Equator that reflects the warmer-get-wetter view. However, this climatological ascending motion marches back and forth across the Equator with the Sun, pumping moisture upwards from the boundary layer and causing seasonal rainfall anomalies to follow a wet-get-wetter pattern. The seasonal mean rainfall, which is the sum of the annual mean and seasonal anomalies, thus combines the wet-get-wetter and warmer-get-wetter trends. Given that precipitation climatology is well observed whereas the pattern of ocean surface warming is poorly constrained, our results suggest that projections of tropical seasonal mean rainfall are more reliable than the annual mean.

Yue Y.,Ocean University of China
Journal of Intelligent and Fuzzy Systems | Year: 2015

This paper attempts to show that separated Δ+-valued equivalences can be viewed as probabilistic partial metric spaces. Some properties of probabilistic partial metric spaces are studied and three kinds of fixed point theorems in probabilistic partial metric spaces are given. © 2015-IOS Press and the authors.

Liu Y.,Ocean University of China | Li Y.-C.,Dalian University of Technology
Ocean Engineering | Year: 2016

This study gives predictive formulas in terms of Keulegan-Carpenter (KC) numbers for the resistance coefficients of perforated walls in Jarlan-type caissons. The predictive formulas are developed and validated using a large number of experimental data from different literatures. The predictive formulas are valid for both regular and irregular waves. Different from previous predictive formulas, the effects of wave height and wavelength (wave period) on the resistance coefficients of perforated walls are well considered in the present formulas. The resistance coefficient decreases with the decreasing incident wave height or wavelength, while increases with the decreasing relative wall thickness. The effect of Reynolds number on the resistance coefficients is also indicated. Based on the newly proposed formulas of resistance coefficients, this study gives closed-form solutions for the reflection coefficients of single-chamber and multi-chamber Jarlan-type perforated caissons. © 2016 Elsevier Ltd.

Xu S.P.,Ocean University of China | Xu S.P.,National University of Singapore
European Journal of Mechanics, A/Solids | Year: 2014

This paper is concerned with obtaining exact solutions for the bending problem of an elastic nanobeam by using the Lurie's operational method. Within the framework of nonlocal elasticity theory, a general governing equation, capable of capturing the size effect, is first constructed in a systematic and straightforward manner. Then a solution methodology is described. Some explicit solutions involving trigonometric expansions are also presented and compared with other well known beam theories. The results indicate that this general beam theory can provide more accurate results, which can be served as benchmarks for other theoretical or numerical methods. © 2014 Elsevier Masson SAS. All rights reserved.

Jinming F.,Ocean University of China
Fuzzy Sets and Systems | Year: 2010

In this paper, a new kind of lattice-valued convergence structures on a universal set, called stratified L-ordered convergence structures, are presented by modifying the axiom for stratified L-generalized convergence structures in the fuzzy setting so as to make use of the intrinsic fuzzy inclusion order on the fuzzy power set. The category of stratified L-ordered convergence spaces described here is shown to be a reflective full subcategory in the category of stratified L-generalized convergence spaces, and hence it is topological and Cartesian-closed. As preparation, a further investigation of stratified L-filters is presented from the viewpoint that latticed-valued filters should be compatible with the intrinsic fuzzy inclusion order on the fuzzy power set. © 2010 Elsevier B.V. All rights reserved.

The mitochondrial cytochrome c oxidase subunit I (COI) gene is being used increasingly for evaluating inter- and intra-specific genetic diversity of ciliated protists. However, very few studies focus on assessing genetic divergence of the COI gene within individuals and how its presence might affect species identification and population structure analyses. We evaluated the genetic variation of the COI gene in five Paramecium species for a total of 147 clones derived from 21 individuals and 7 populations. We identified a total of 90 haplotypes with several individuals carrying more than one haplotype. Parsimony network and phylogenetic tree analyses revealed that intra-individual diversity had no effect in species identification and only a minor effect on population structure. Our results suggest that the COI gene is a suitable marker for resolving inter- and intra-specific relationships of Paramecium spp.

Yue Y.,Ocean University of China | Shi F.-G.,Beijing Institute of Technology
Fuzzy Sets and Systems | Year: 2010

This paper attempts to endow the fuzzy pseudo-metric in the sense of George and Veeramani with many-valued topological structures. It is shown that George and Veeramani's fuzzy pseudo-metric can be characterized by a family of compatible ordinary pseudo-metrics called pseudo-metric chain in this paper. Then, two kinds of many-valued topological structures-fuzzifying topology and fuzzifying uniformity-are generated by this fuzzy pseudo-metric, and their properties are also investigated. © 2009 Elsevier B.V. All rights reserved.

Taha-Tijerina J.,Rice University | Narayanan T.N.,Rice University | Gao G.,Rice University | Gao G.,Ocean University of China | And 4 more authors.
ACS Nano | Year: 2012

Different nanoscale fillers have been used to create composite fluids for applications such as thermal management. The ever increasing thermal loads in applications now require advanced operational fluids, for example, high thermal conductivity dielectric oils in transformers. These oils require excellent filler dispersion, high thermal conduction, but also electrical insulation. Such thermal oils that conform to this thermal/electrical requirement, and yet remain in highly suspended stable state, have not yet been synthesized. We report here the synthesis and characterization of stable high thermal conductivity Newtonian nanofluids using exfoliated layers of hexagonal boron nitride in oil without compromising its electrically insulating property. Two-dimensional nanosheets of hexagonal boron nitride are liquid exfoliated in isopropyl alcohol and redispersed in mineral oil, used as standard transformer oil, forming stable nanosuspensions with high shelf life. A high electrical resistivity, even higher than that of the base oil, is maintained for the nano-oil containing small weight fraction of the filler (0.01 wt %), whereas the thermal conductivity was enhanced. The low dissipation factor and high pour point for this nano-oil suggests several applications in thermal management. © 2012 American Chemical Society.

Liu X.,CAS Qingdao Institute of Oceanology | Liu X.,Guangxi Institute of Oceanology | Zhou Y.,CAS Qingdao Institute of Oceanology | Yang H.,CAS Qingdao Institute of Oceanology | Ru S.,Ocean University of China
PLoS ONE | Year: 2013

Eelgrass ecosystems have a wide variety of ecological functions in which living tissues and detritus may be a food source for many marine animals. In this study, we conducted a laboratory simulating experiment to understand the trophic relationship between the eelgrass Zostera marina L and the sea cucumber Apostichopus japonicus. A mixture of decaying eelgrass debris and seafloor surface muddy sediments was used as food to feed A. japonicus, and then specific growth rates (SGR) and fecal production rates (FPR) were measured. According to the proportion of eelgrass debris, we designed five treatment diets, i.e., ES0, ES10, ES20, ES40, and ES100, with eelgrass debris accounting for 0%, 10%, 20%, 40%, and 100% in dry weight, respectively. Results showed that diet composition had a great influence on the growth of A. japonicus. Sea cucumbers could use decaying eelgrass debris as their food source; and when the organic content of a mixture of eelgrass debris and sediment was 19.6% (ES40), a relatively high SGR (1.54%·d-1) and FPR (1.31 g·ind.-1 d-1) of A. japonicus were obtained. It is suggested that eelgrass beds can not only provide habitat for the sea cucumber A. japonicus but can also provide an indirect food source for the deposit feeder. This means that the restoration and reconstruction of eelgrass beds, especially in coastal waters of China, would be a potential and effective measure for sea-cucumber fisheries, in respect to both resource restoration and aquaculture of this valuable species. © 2013 Liu et al.

Xu J.,Ocean University of China
Zhonghua gan zang bing za zhi = Zhonghua ganzangbing zazhi = Chinese journal of hepatology | Year: 2013

To study the relationship between the patatin-like phospholipase domain-containing protein 3 (PNPLA3) gene and hereditary susceptibility to non-alcoholic fatty liver disease (NAFLD) by detecting single nucleotide polymorphisms (SNPs). Peripheral blood DNA from 315 patients diagnosed with NAFLD (including the spectrum of simple steatosis (SS) and non-alcoholic steatosis (NASH)) and 336 control subjects was used to determine the PNPLA3 genotype by polymerase chain reaction (PCR) and direct sequencing. The relationship of SNPs and NAFLD-related markers of liver function were assessed by correlation analysis. The SNP rs738409 was identified in more of the NAFLD patients (allele variant frequencies: NAFLD, 65.40%; NASH: 71.87%; SS, 56.47%) than in the controls (33.18%). Case-control analysis revealed that carriers of the 148GG genotype were at 3.81-fold (95% CI: 3.03 ~ 4.79) higher risk of developing NAFLD and at 1.97-fold (95% CI: 1.41 ~ 2.75) higher risk of progressing from SS to NASH, compared with non-carriers. rs738409 was also found to be associated with serum levels of alanine aminotransferase (ALT) and y-glutamyltransferase (y-GT) (both P less than 0.05). Carriers of the 148GG genotype had significantly higher body mass index, ALT, and fasting insulin than carriers of the 148CC genotype (all P less than 0.05), and significantly higher level of serum HDL than carriers of either the 148CC genotype or the 148GC genotype (both P less than 0.05). Polymorphisms in the PNPLA3 gene may play an important role in mediating susceptibility to developing NAFLD in the Chinese population. The rs738409 polymorphism, in particular, is related to development and progression of NAFLD and may play a role in the contribution of PNPLA3 to NAFLD pathogenesis.

Fang J.,Ocean University of China
Fuzzy Sets and Systems | Year: 2010

By making use of the intrinsic fuzzy inclusion orders on the fuzzy power set, the relationships between L-ordered convergence spaces and strong L-topological spaces are researched, where L is a commutative unital quantale. It is shown that the category of strong L-topological spaces can be embedded in the category of L-ordered convergence spaces as a reflective subcategory. As a result, we observe that there is a Galois correspondence between the category of L-ordered convergence spaces and the category of strong L-topological spaces. Further, it is proved that the class of all strong L-topological L-ordered convergence spaces precisely is the class of all strong L-topological spaces, and the class of spaces with non-idempotent L-ordered interior operators is characterized as a subclass of the class of L-ordered convergence spaces. © 2010 Elsevier B.V. All rights reserved.

Hu X.,Ocean University of China
Journal of Eukaryotic Microbiology | Year: 2014

As eukaryotic microbial life, ciliated protozoan may be found actively growing in some extreme condition where there is a sufficient energy source to sustain it because they are exceedingly adaptable and not notably less adaptable than the prokaryotes. However, a crucial problem in the study of ciliates in extreme environments is the lack of reliable cultivation techniques. To our knowledge, only a tiny fraction of ciliates can be cultured in the laboratory, even for a very limited period, which can partly explain the paucity of our understanding about ciliates diversity in various extremes although the interest in the biodiversity of extremophiles increased significantly during the past three decades. This mini-review aims to compile the knowledge of several groups of free-living ciliates that can be microscopically observed in extreme environmental samples, although most habitats have not been sufficiently well explored for sound generalizations. © 2014 The Author(s) Journal of Eukaryotic Microbiology © 2014 International Society of Protistologists.

Xing H.,Qingdao Agricultural University | Li D.,Tsinghua University | Gao C.,Ocean University of China | Kao Y.,Harbin Institute of Technology
Journal of the Franklin Institute | Year: 2013

The sliding mode control (SMC) problem for a class of quasi-linear parabolic partial differential equation (PDE) systems with time-varying delay is considered. Firstly, the stability problem for the reduced order sliding dynamical equations is investigated and a sufficient condition for the stability of sliding motion is given. Then the SMC law, which forces the system state from any initial state to reach the sliding manifold within finite time, is designed. At last a simulation example is presented to illustrate effectiveness of the proposed method. Copyright © 2012 Published by Elsevier Ltd.

Wang Y.,CAS Guangzhou Institute of Geochemistry | Wang Y.,Northwest University, China | Zhang A.,CAS Guangzhou Institute of Geochemistry | Fan W.,CAS Guangzhou Institute of Geochemistry | And 5 more authors.
Lithos | Year: 2011

Gneissoid granites were traditionally thought to be the components of the Precambrian basement in the eastern South China Block, but twenty-four gneissoid granite samples from the Wugong, northern Wuyi, southern Wuyi and Yunkai Domains gave zircon U-Pb ages of 424-456Ma, 410-457Ma, 426-438Ma and 415-450Ma, respectively. The existence of the abundant Kwangsian gneissoid granites, which have incorrectly been assigned to the Precambrian basement, indicates that the "so-called" Precambrian stratigraphic sequence of the Cathaysia Block should be termed "Complex" rather than "Group". These gneissoid granites are peraluminous granites with relatively high Al2O3, MgO, TiO2, FeOt and CaO/Na2O but low CaO, Al2O3/(MgO+FeOt) and Rb/Sr ratios. They exhibit strongly negative Ba, Sr, Nb, P and Ti and positive Pb anomalies in primitive mantle-normalized diagrams, and have initial 87Sr/86Sr ratios ranging from 0.70924 to 0.72935 and negative εNd(t) values from -6.4 to -11.4, similar to those of paragneissic enclaves and Precambrian sedimentary rocks in the eastern South China Block. The zircons crystallized in the Kwangsian gneissoid granites gave εHf(t) values ranging from +2.4 to -19.4 with the peak at -4 (almost all grains clustering at -1 to -12) and Hf model ages of 1.1-2.1Ga. The synthesis of these geochemical and in-situ zircon Hf isotopic data indicates that the Kwangsian gneissoid granites dominantly originated from Proterozoic metapelitic and meta-igneous components with insignificant input of juvenile mantle-derived magmas. A model of two-stage crustal anatexis is proposed for the Kwangsian granitic magma in the eastern South China Block, with (1) the formation of 460-430Ma granite through the breakdown of hydrous minerals under the condition of the doubly thickened crust, and (2) the generation of the 430-400Ma granite accompanying promoted melting along a path of isothermal decompression due to the increasing thermal weakening for the collapse of the thickened crust. The crustal anatexis has probably occurred in an intracontinental tectonic regime that was geodynamically linked to the far-field response to the assembly of the Australian-Indian plate with the Cathaysia Block during middle Paleozoic (Kwangsian) time. © 2011 Elsevier B.V.

Verleye T.J.,Ghent University | Pospelova V.,Ocean University of China | Mertens K.N.,Ghent University | Louwye S.,Ghent University
Marine Micropaleontology | Year: 2011

Detailed palynological studies in the northeast (NE) Pacific, Strait of Georgia (BC, Canada), southeast (SE) Pacific and northwest Pacific (Dongdo Bay, South Korea) resulted in the recognition of the new dinoflagellate cyst species Selenopemphix undulata sp. nov. This species is restricted to cool temperate to sub-polar climate zones, where it is found in highest relative abundances in highly productive non- to reduced upwelling regions with an annual mean sea-surface temperature (aSST) below 16 °C and an annual mean sea-surface salinity (aSSS) between 20 and 35. psu. Those observations are in agreement with the late Quaternary fossil records from Santa Barbara Basin (ODP 893; 34°N) and offshore Chile (ODP 1233; 41°S), where this species thrived during the last glacial. This period was characterised by high nutrient availability and the absence of species favouring upwelling conditions. The indirect dependence of S. undulata sp. nov. abundances on nutrient availability during reduced or non-upwelling periods is expressed by the synchronous fluctuations with diatom abundances, since the distribution and growth rates of the latter are directly related with the availability of macronutrients in the surface waters. © 2010 Elsevier B.V.

Gao Z.,Ocean University of China | Don W.S.,Hong Kong Baptist University
Journal of Scientific Computing | Year: 2013

In this study, we employ the fifth order hybrid Central-WENO conservative finite difference scheme (Hybrid) in the simulation of detonation waves. The Hybrid scheme is used to keep the solutions parts displaying high gradients and discontinuities always captured by the WENO-Z scheme in an essentially non-oscillatory manner while the smooth parts are highly resolved by an efficient and accurate central finite difference scheme and to speedup the computation of the overall scheme. To detect the smooth and discontinuous parts of the solutions, a high order multi-resolution algorithm by Harten is used. A tangent domain mapping is used to cluster grid points near the detonation front in order to enhance the grid resolution within half reaction zone that drives the development of complex nonlinear wave structures behind the front. We conduct several numerical comparisons among the WENO-Z scheme with a uniformly spaced grid, the WENO-Z scheme and the Hybrid scheme with the domain mapping in simulations of classical stable and unstable detonation waves. One- and two-dimensional numerical examples show that the increased grid resolution in the half reaction zone by the Mapped WENO-Z scheme and the Mapped Hybrid scheme allows a significant increased efficiency and accuracy when compares with the solution obtained with a highly resolved one computed by the WENO-Z scheme with a uniformly spaced grid. Results of three-dimensional simulations of stable, slightly unstable and highly unstable detonation waves computed by the Mapped Hybrid scheme are also presented. © Springer Science+Business Media, LLC 2012.

Jia Y.,Ocean University of China | Jia Y.,Florida State University | Chassignet E.P.,Florida State University
Journal of Oceanography | Year: 2011

Altimeter data and output from the HYbrid Coordinate Ocean Model global assimilation run are used to study the seasonal variation of eddy shedding from the Kuroshio intrusion in the Luzon Strait. The results suggest that most eddy shedding events occur from December through March, and no eddy shedding event occurs in June, September, or October. About a month before eddy shedding, the Kuroshio intrusion extends into the South China Sea and a closed anticyclonic eddy appears inside the Kuroshio loop which then detaches from the Kuroshio intrusion. Anticyclonic eddies detached from December through February move westward at a speed of about 0.1 m s -1 after shedding, whereas eddies detached in other months either stay at the place of origin or move westward at a very slow speed (less than 0.06 m s -1). The HYCOM outputs and QuikSCAT wind data clearly show that the seasonal variation of eddy shedding is influenced by the monsoon winds. A comparison between eddy volume and integrated Ekman transport indicates that, once the integrated Ekman transport exceeds 2 × 10 12 m 3 (which roughly corresponds to the volume of an eddy), the Kuroshio intrusion expands and an eddy shedding event occurs within 1 month. We infer that the Ekman drift of the northeasterly monsoon pushes the Kuroshio intrusion into the SCS, creates a net westward transport into the Strait, and leads to an eddy detachment from the Kuroshio. © 2011 The Oceanographic Society of Japan and Springer.

Sun M.,Ocean University of China | Lam J.,University of Hong Kong
International Journal of Robust and Nonlinear Control | Year: 2015

Summary: This paper is concerned with the optimal time-weighted H2 model reduction problem for discrete Markovian jump linear systems (MJLSs). The purpose is to find a mean square stable MJLS of lower order such that the time-weighted H2 norm of the corresponding error system is minimized for a given mean square stable discrete MJLSs. The notation of time-weighted H2 norm of discrete MJLS is defined for the first time, and then a computational formula of this norm is given, which requires the solution of two sets of recursive discrete Markovian jump Lyapunov-type linear matrix equations. Based on the time-weighted H2 norm formula, we propose a gradient flow method to solve the optimal time-weighted H2 model reduction problem. A necessary condition for minimality is derived, which generalizes the standard result for systems when Markov jumps and the time-weighting term do not appear. Finally, numerical examples are used to illustrate the effectiveness of the proposed approach. © 2015 John Wiley & Sons, Ltd.

Xu H.,Nanjing University of Information Science and Technology | Xu M.,Nanjing University of Information Science and Technology | Xie S.-P.,University of Hawaii at Manoa | Xie S.-P.,Ocean University of China | Wang Y.,University of Hawaii at Manoa
Journal of Climate | Year: 2011

The atmospheric response to the spring Kuroshio Front over the East China Sea is investigated using a suite of high-resolution satellite data and a regional atmospheric model. The atmospheric response appears to extend beyond the marine atmospheric boundary layer, with frequent occurrence of cumulus convection. In spring, Quick Scatterometer (QuikSCAT) wind speed shows a clear effect of sea surface temperature (SST), with high (low) wind speed observed over the warm (cold) tongue. This in-phase relationship between SST and surface wind speed is indicative of SST influence on the atmosphere. Wind convergence is found on the warmer flank of the Kuroshio Front, accompanied by a narrow rainband. The analysis of satellite-borne radar measurements indicates that deep convection appears over the Kuroshio warm tongue in the spring season, with enhanced convective precipitation, frequent occurrence of cumulus convection, and increased precipitation (cloud) tops in altitude. These deep convective activities along the Kuroshio warm tongue are further supported by enhanced lightning flash rate observed by satellite and atmospheric heating estimated by a Japanese reanalysis. The Weather Research and Forecasting (WRF) model is used to investigate the precipitation response to the spring Kuroshio SST front over the East China Sea. Forced by observed SST [control (CTL)], the model well simulates a narrow band of precipitation, high wind speed, and surface wind convergence that closely follows the Kuroshio warm current, consistent with satellite observations. This narrow rainband completely disappears in the model when the SST front is removed by horizontally smoothed SST (SmSST). The results show that it is convective precipitation that is sensitive to the Kuroshio SST front. A case study for an eastward-moving extratropical cyclone indicates that convective precipitation increases its intensity and duration in the CTL run compared to the SmSST run. Local enhancement of upward sensible and latent heat fluxes and convective instability in the lower atmosphere are the key to anchoring the narrow band of convective precipitation that closely follows the Kuroshio. © 2011 American Meteorological Society.

Chen J.,Ocean University of China | Cui T.,First Institute of Oceanography
Journal of Geophysical Research C: Oceans | Year: 2015

In this study, a neural network-based four-band model (NNFM) for the global oceanic and coastal waters has been developed in order to retrieve the total absorption coefficients a(λ). The applicability of the quasi-analytical algorithm (QAA) and NNFM models is evaluated by five independent data sets. Based on the comparison of a(λ) predicted by these two models with the field measurements taken from the global oceanic and coastal waters, it was found that both the QAA and NNFM models had good performances in deriving a(λ), but that the NNFM model works better than the QAA model. The results of the QAA model-derived a(λ), especially in highly turbid waters with strong backscattering properties of optical activity, was found to be lower than the field measurements. The QAA and NNFM models-derived a(λ) could be obtained from the MODIS data after atmospheric corrections. When compared with the field measurements, the NNFM model decreased by a 0.86-24.15% uncertainty (root-mean-square relative error) of the estimation from the QAA model in deriving a(λ) from the Bohai, Yellow, and East China seas. Finally, the NNFM model was applied to map the global climatological seasonal mean a(443) for the time range of July 2002 to May 2014. As expected, the a(443) value around the coastal regions was always larger than the open ocean around the equator. Viewed on a global scale, the oceans at a high latitude exhibited higher a(443) values than those at a low latitude. © 2014. American Geophysical Union. All Rights Reserved.

Huang Z.,Nanyang Technological University | Li Y.,Dalian University of Technology | Liu Y.,Ocean University of China
Ocean Engineering | Year: 2011

This paper reviews recent progress in the study of perforated/slotted breakwaters, with an emphasis on two main groups of such breakwaters: (1) perforated/slotted breakwaters with impermeable back walls, and (2) perforated/slotted breakwaters without a back-wall. The methods commonly used to simulate the interactions between such structures and various linear/nonlinear waves are summarized. The transmission and reflection characteristics of perforated/slotted breakwaters in these two groups are reviewed extensively. Several methods for calculating wave forces on perforated caissons are also reviewed. Some recent works published in Chinese journals, which are generally not well-known to non-Chinese researchers, are reviewed with a hope that these works can be beneficial to other researchers working in this area. © 2011 Elsevier Ltd. All rights reserved.

Hou S.,Ocean University of China
Physical Chemistry Chemical Physics | Year: 2013

The relations between the harmonic frequencies of different molecules are revealed with the aid of the spring constants of atoms in molecules. Using the atomic spring constants in the related molecules, the force constants for a new molecule can be estimated. The simplest scheme to obtain the force constant of a given molecule is similar to a simple chemical reaction formula, such as A 2 + B2 → AB, and the corresponding relation between the molecular force constants is kAB -1 = (2kA 2)-1 + (2kB2)-1. For a given molecule, one can design numerous schemes to obtain its force constant from the atomic spring constants in other molecules. A high degree of periodical regularity appears in the application of different kinds of schemes to the ground states. The reliable schemes for the ground electronic states can be adopted for the excited states. Over two hundred molecules with experimental data available for comparison have been tested. The discrepancies between the calculated and the experimental harmonic frequencies can reach 1% and better; the results show that the present approach is simple in theory and handy to use. The harmonic frequencies for dozens of hetero-nuclear molecules of the transition-metal elements are also predicted. © the Owner Societies 2013.

Su N.,East China Normal University | Du J.,East China Normal University | Liu S.,Ocean University of China | Zhang J.,East China Normal University
Deep-Sea Research Part II: Topical Studies in Oceanography | Year: 2013

The horizontal and vertical transport of nutrient-rich water both from the coast and from the seafloor to the overlying water column should play an important role in supplying nutrients required for the periods of vegetative or reproductive growth of phytoplankton. In the present work, radium isotopes (223Ra, 224Ra and 226Ra) in the southern Yellow Sea were measured after a spring bloom in June 2009. The exponential-like decrease of 223Ra away from the coast to offshore waters yielded horizontal eddy diffusivities (Kh) of (2.93±1.47)×107cm2s-1 by neglecting the advection. This estimate was smaller than that with advection indicator by as much as 21% when using an analytic model for 223Ra and 226Ra. The corresponding horizontal nutrient fluxes were 1525μmolm-2d-1 (DIN), 15.9μmolm-2d-1 (DIP) and 826μmolm-2d-1 (DSi), which would supply around 16% of N and 3% of P requirements based on the primary productivity. The decrease of 224Ra and 223Ra activities from sediments to the upper water column suggests the vertical eddy diffusion coefficient (Kz) of 6.23±5.58cm2s-1 below the thermocline, which was within the Yellow Sea Cold Water Mass (YSCWM). The calculated vertical fluxes of nutrient were 4945μmolm-2d-1 (DIN), 236μmolm-2d-1 (DIP) and 5315μmolm-2d-1 (DSi), accounting for up to 52% of N and 40% of P requirements for the phytoplankton growth. These results demonstrate the role of YSCWM as a relative nutrient-rich pool for the supply of nutrient to the southern Yellow Sea via the vertical diffusion process relative to the horizontal process during the summer season. Such processes will be strengthened during the weak density stratification in spring when algal blooms occur. © 2013 Elsevier Ltd.

Yang H.-Z.,Shanghai JiaoTong University | Li H.-J.,Ocean University of China
Zhendong yu Chongji/Journal of Vibration and Shock | Year: 2010

The time domain nonlinear dynamic analysis of a steel catenary riser (SCR) was introduced for fatigue life prediction. Since the behavior of the SCR is nonlinear in nature, the time domain analysis is better suited to capture the possible nonlinear effects associated with hydrodynamic nonlinearities and structural nonlinear properties. The dynamic response simulation of a SCR under oceanic environmental loads was carried out. The time histories of stresses were employed to predict the global riser fatigue life by use of S-N curves. Results were presented from a parametric study of the SCR with various input parameters, such as drag coefficient, buoyancy factors, seabed stiffness etc. It is shown that the predicted fatigue life is strongly dependent on these parameters. The analysis conclusions can help designers to understand the dynamic behavior of SCR and provide guidance for selection of some critical parameters used in SCR fatigue design.

Liang X.,Nagoya University | Liang X.,Ocean University of China | Zhou M.,Nagoya University | Kato K.,Nagoya University | Asanuma H.,Nagoya University
ACS Synthetic Biology | Year: 2013

We demonstrated the generality of a strategy for photoswitching the activity of functional oligonucleotides by modulating their topological structure. Our strategy was proved to be versatile because it can be used to photoregulate functional oligonucleotides, e.g., ribozymes and DNAzymes, which have two binding arms and a catalytic loop. Repeated reversible photoregulation of RNA cleavage by a ribozyme or a DNAzyme was achieved by attaching two photoresponsive strands, artificial oligomers involving azobenzene moieties and nucleobases capable of forming a duplex as the supraphotoswitch. Individual strands were attached to the 3′ and 5′ ends of a RNA-cleavage oligonucleotide. Thus, the topological structure of the ribozyme or DNAzyme was constrained, and RNA cleavage was greatly suppressed when the supraphotoswitch duplex formed (OFF state). In contrast, RNA cleavage resumed when the supraphotoswitch duplex dissociated (ON state). Light irradiation was used to repeatedly switch the supraphotoswitch between the ON and OFF states so that RNA cleavage activity could be efficiently photoregulated. Analysis of the regulatory mechanism showed that topological constraints suppressed the RNA cleavage by causing both structural changes at the catalytic site and lower binding affinity between the RNA substrates and the functional oligonucleotides. © 2013 American Chemical Society.

Liu X.,Chinese Academy of Geological Sciences | Jahn B.-M.,National Taiwan University | Li S.,Ocean University of China | Liu Y.,Wuhan University
Tectonophysics | Year: 2013

The Tongbai orogen is located in a key tectonic position linking the Qinling orogen to the west and the Dabie-Sulu orogen to the east. This orogen comprises a Paleozoic accretionary orogenic system in the north and a Permo-Triassic collisional orogenic system in the south; hence it may serve as an ideal place to unravel the tectonic evolution from the initial oceanic subduction/accretion to the final continental collision between the Sino-Korean and Yangtze cratons. U. Pb zircon geochronology of metasedimentary and metaigneous rocks and geochemical characterization of metabasalts indicate a close genetic relationship between the individual tectonic units of the Paleozoic accretionary orogenic system: (1) the Kuanping Group as a Neoproterozoic-Ordovician subduction-accretion complex which received sediments from the Qinling microcontinent, (2) the Erlangping Group and Huanggang diorite-granodiorite complex as an Ordovician-Silurian island arc evolving from backarc basin, (3) the Qinling Group as a Precambrian microcontinent converted into continental arc during the Ordovician, (4) the Guishan Complex as a mixture of the Qinling continental arc and Devonian forearc sediments, and (5) the Nanwan Flysch as a Devonian forearc sequence deposited on the newly accreted active margin of the Sino-Korean craton. Consequently, the northern and southern boundaries of the Paleozoic accretionary orogenic system represent two sutures of the Qinling microcontinent with the Sino-Korean and Yangtze cratons. The new and previously published data reveal that the tectonic evolution of the Tongbai orogen involved a series of events from Ordovician-Early Silurian (ca 490-440 Ma) oceanic subduction and arc magmatism, Silurian-Early Devonian (ca. 440-400. Ma) arc-continent collision, Carboniferous (ca 340-310 Ma) oceanic subduction and accretion, Late Permian-Triassic (ca 260-200 Ma) continental subduction and collision, to Cretaceous (ca. 140-90. Ma) extension and lateral eastward extrusion. The entire accretionary orogenic processes until the final collision between the Sino-Korean and Yangtze cratons may have lasted more than 200. Ma. © 2013.

Peng J.,Rice University | Peng J.,Nanjing University | Gao W.,Rice University | Gupta B.K.,Rice University | And 16 more authors.
Nano Letters | Year: 2012

Graphene quantum dots (GQDs), which are edge-bound nanometer-size graphene pieces, have fascinating optical and electronic properties. These have been synthesized either by nanolithography or from starting materials such as graphene oxide (GO) by the chemical breakdown of their extended planar structure, both of which are multistep tedious processes. Here, we report that during the acid treatment and chemical exfoliation of traditional pitch-based carbon fibers, that are both cheap and commercially available, the stacked graphitic submicrometer domains of the fibers are easily broken down, leading to the creation of GQDs with different size distribution in scalable amounts. The as-produced GQDs, in the size range of 1-4 nm, show two-dimensional morphology, most of which present zigzag edge structure, and are 1-3 atomic layers thick. The photoluminescence of the GQDs can be tailored through varying the size of the GQDs by changing process parameters. Due to the luminescence stability, nanosecond lifetime, biocompatibility, low toxicity, and high water solubility, these GQDs are demonstrated to be excellent probes for high contrast bioimaging and biosensing applications. © 2012 American Chemical Society.

Hong Y.,Zhejiang University | Ng C.W.W.,Hong Kong University of Science and Technology | Liu G.B.,Tongji University | Liu T.,Ocean University of China
Tunnelling and Underground Space Technology | Year: 2015

Despite the large number of excavation-induced ground deformations reported in the literature, it is still not easy to differentiate ground deformations due to excavation in congested sites (where the ground is strengthened by underground structures) from those due to excavation in "greenfield" sites. To investigate and compare excavation-induced ground deformations in "greenfield" sites and congested sites, in this study a multi-propped excavation at a "greenfield" site in Shanghai soft clay was heavily instrumented and the measured ground deformations were compared with those reported from six excavations conducted under similar conditions but in congested sites in Shanghai. Field measurements from the "greenfield" site show that near the centre of the excavation, the maximum ground settlement (δv-max) ranged from 0.22% to 0.27% of the final excavation depth (He), with a major influence zone extending to 3. He behind the wall. The six excavations (near the main station) at congested sites in Shanghai had δv-max values ranging from 0.01% to 0.1% He (with a mean of about 0.05% He) and so were about 20% of that at the "greenfield" site. In addition, the major influence zone of ground settlement at the "greenfield" site extended 33% further than those at the congested sites. On the other hand, the measured maximum lateral wall displacement δh-max (0.24-0.37% He) at the "greenfield" site was comparable to those (0.13-0.43% He) at the congested sites. Due to the corner effect (soil arching around corners) at the "greenfield" site, the average δh-max and δv-max near the corners of the site were 45% and 36% smaller than those near the centre. The maximum tilt of ground perpendicular to the excavation was 1/1064, which was similar to that parallel to the excavation (1/1050). © 2014 Published by Elsevier Ltd.

Nan F.,Ocean University of China | He Z.,CAS South China Sea Institute of Oceanology | Zhou H.,CAS Qingdao Institute of Oceanology | Wang D.,CAS South China Sea Institute of Oceanology
Journal of Geophysical Research: Oceans | Year: 2011

In August 2007, three long-lived anticyclonic eddies (ACE1, ACE2, and ACE3) were detected by both satellite sea level anomaly (SLA) map and in situ measurements in the northern South China Sea (SCS). ACE3 had a two-core (ACE3(1) and ACE3(2)) structure. In situ stations along 18°N almost cut through the centers of ACE2 and ACE3(2). Near the centers of ACE2 and ACE3(2), mean temperature and sound velocity are ∼0.657deg;C and ∼2 m s-1 larger than those in their surrounding areas, respectively, while mean salinity and density are ∼0.02 psu and ∼0.15 m3 s-1 smaller than those in their surrounding areas due to downwelling near the eddy cores. The depths of maximum and minimum salinity near the eddy cores are ∼65 m and ∼35 m larger than those in their surrounding areas. The vertical depth with current speed larger than 0.05 m s-1 can reach ∼900 m. Their detailed evolutionary processes were depicted based on the variation of geostrophic currents and the trajectories of five drifting buoys. ACE1 lasted 147 days, while ACE2 and ACE3 lasted 168 days and 210 days, respectively. ACE1 had a smaller mean SLA (18.8 cm) in its lifetime than ACE2 (21.8 cm) and ACE3 (25.3 cm) but had a larger negative mean vorticity (-7.7 × 10-6 s-1) than ACE2 (-7.0 × 10-6 s-1) and ACE3 (-7.0 × 10-6 s-1). One short-lived anticyclonic eddy that split from ACE2 and another one that merged with ACE3 both had a smaller SLA, negative vorticity, and diameter than ACE2 and ACE3, respectively. Copyright 2011 by the American Geophysical Union.

Luo Y.,University of Rhode Island | Liu Q.,Ocean University of China | Rothstein L.M.,University of Rhode Island
Geophysical Research Letters | Year: 2011

The response of South Pacific Eastern Subtropical Mode Water (SPESTMW) to global warming is investigated by comparing solutions from a set of Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) coupled models between a present-day climate and a future, warmer climate. Under the warmer climate scenario, the SPESTMW extends southwestward and is significantly increased in volume. This is because all the local surface forcing mechanisms (i.e., wind stress, heat and freshwater fluxes) in the eastern subtropical South Pacific tends to de-stratify the upper ocean and thus deepen the mixed layer. Further, a suite of process-oriented experiments with an ocean general circulation model suggest that it is the intensified southeast trade winds under the warmer climate that promotes more heat flux from the ocean into the atmosphere that then results in a deepening of the mixed layer in the eastern subtropics of the South Pacific. Copyright © 2011 by the American Geophysical Union.

Du Y.,CAS South China Sea Institute of Oceanology | Yang L.,CAS South China Sea Institute of Oceanology | Xie S.-P.,University of Hawaii at Manoa | Xie S.-P.,Ocean University of China
Journal of Climate | Year: 2011

In the summer following a strong El Niño, tropical cyclone (TC) number decreases over the Northwest (NW) Pacific despite little change in local sea surface temperature. The authors' analysis suggests El Niño-induced tropical Indian Ocean (TIO) warming as the cause. The TIO warming forces a warm tropospheric Kelvin wave that propagates into the western Pacific. Inducing surface divergence off the equator, the tropospheric Kelvin wave suppresses convection and induces an anomalous anticyclone over the NW Pacific, both anomalies unfavorable for TCs. The westerly vertical shear associated with the warm Kelvin wave reduces the magnitude of vertical shear in the South China Sea and strengthens it in the NW Pacific, an east-west variation that causes TC activity to increase and decrease in respective regions. These results help improve seasonal TC prediction. © 2011 American Meteorological Society.

Luo Y.,Ocean University of China | Bian F.-H.,Yantai University | Luo Y.-B.,CAS Institute of Botany
International Journal of Plant Sciences | Year: 2012

Pseudostellaria heterophylla, a cleistogamous species belonging to the Caryophyllaceae, was studied ontogenetically with SEM to investigate floral development in chasmogamous (CH) flowers and cleistogamous (CL) flowers. Comparative ontogenetic studies of this cleistogamous species revealed significant differences between CH and CL flowers. As opposed to other findings for cleistogamous species, the results of this study showed that divergence in the development of the floral forms occurs at inception, not later during organ growth. The floral organ inception in the CH flower is as follows: five sepal primordia are initiated in a helical sequence, 10 stamen primordia are initiated in two whorls (an antesepalous whorl and an antepetalous whorl sequentially), petal primordia are initiated by the division of common stamen-petal primordia, and three carpel primordia are initiated last. The floral organ inception in the CL flower is as follows: four sepal primordia are initiated in two pairs alternatively, two stamen primordia are initiated oppositely, no petal primordia are initiated, and two carpel primordia are initiated last. In comparison with the CH flower, fewer floral organs are initiated in the CL flower. No other reports of cleistogamic differences similar to those observed here for P. heterophylla are to be found in the literature. The reduction pattern in the CL flower is somewhat similar to that observed in the rest of the members of the Caryophyllaceae family. It is concluded that the CL flower is not a developmental modification of the CH flower and that the four sepals of the CL flower may arise as a continuation of bracteole initiation. © 2012 by The University of Chicago. All rights reserved.

Fu X.T.,Ocean University of China | Kim S.M.,Gangneung - Wonju National University
Marine Drugs | Year: 2010

Agarases are the enzymes which catalyze the hydrolysis of agar. They are classified into α-agarase (E.C. and β-agarase (E.C. according to the cleavage pattern. Several agarases have been isolated from different genera of bacteria found in seawater and marine sediments, as well as engineered microorganisms. Agarases have wide applications in food industry, cosmetics, and medical fields because they produce oligosaccharides with remarkable activities. They are also used as a tool enzyme for biological, physiological, and cytological studies. The paper reviews the category, source, purification method, major characteristics, and application fields of these native and gene cloned agarases in the past, present, and future. © 2010 by the authors; licensee Molecular Diversity Preservation International.

Shen H.X.,Ocean University of China
Advances in Energy, Environment and Materials Science - Proceedings of the International Conference on Energy, Environment and Materials Science, EEMS 2015 | Year: 2016

T Sewage Company has three wastewater treatment plants. However, T Company always can’t meet the national standard of the total nitrogen and phosphorus emissions and needs to use the nitrogen and phosphorus removal agent to decrease the emissions, making the operating costs increase. This paper compares the aluminum sulfate, ferric chloride, and polymeric aluminum chloride to the sewage PH value, SS, COD, and TP removal effect based on the experiment and obtains the appropriate ratio of gas and water through experiments. We used the experimental results in the T wastewater treatment plant and had good economic and environmental protection results. © 2016 Taylor & Francis Group, London.

Zhang F.,Nanjing Agricultural University | Shi Y.,Nanjing Panda Electronics Co. | Zhao Z.,Ocean University of China | Song W.,Ningbo Institute of Materials Technology and Engineering | Cheng Y.,Wuhan University of Science and Technology
Applied Catalysis B: Environmental | Year: 2014

The Fe3O4/SiO2/polythiophene (FSP) submicron composite (SC) with a structure of semiconductor/insulator/semiconductor (SIS) was obtained. The characterization results showed that the FSP SC had a spherical core/shell shape with an average diameter of 506nm. The high saturated magnetization value (~39emu/g) ensured the easy separation of FSP SC from aqueous solution. The photo-catalytic activity of the FSP SC was evaluated by the degradation of methyl orange (MO) under UV-irradiation in the presence of H2O2. Due to the SIS structure, the degradation rate constant by FSP SC (0.02177min-1) was 6.4, 1.6, and 2.5 times higher than that of Fe3O4/polythiophene (FP), polythiophene (P), and TiO2, respectively. The repetition results suggested the good photochemical stability of FSP SC. The mechanism was proposed by investigating the energy band variation of the SIS structure, the transfer of light generated carriers and the formation of effective hydroxyl radicals in the photo-catalysis progress. © 2014 Elsevier B.V.

Chu Z.,Ocean University of China | Chu Z.,California Institute of Technology
Geomorphology | Year: 2014

The Yellow River has been considerably altered over the past half century from human activities. These perturbations provide a rare opportunity to document how this natural system has responded to anthropogenic impacts on channel hydrodynamics. Using a six-decade record data set, I analyze and summarize changing patterns in erosion and sedimentation of a downstream channel with three units (km3/y, Gt/y, and cm/y), and the response to human impacts upstream. The changing pattern of channel-bed erosion and deposition in the lower reach during 1952-2007 is divided into five phases in terms of erosion and deposition rates and human activities: (1) a rapid and quasi-natural deposition phase (1952-1959, 0.25km3/y or 10cm/y) with few main human effects, (2) a rapid erosion phase (1960-1964, -0.36km3/y or -14cm/y) in response to heavy sedimentation in the Sanmenxia reservoir, (3) a rapid deposition phase (1965-1973, 0.32km3/y or 13cm/y) in response to sediment release from the Sanmenxia reservoir, (4) a moderate erosion and deposition phase with a net deposition (1974-1999, 0.10km3/y or 4cm/y) in response to the Sanmenxia reservoir practice of storing clear water and discharging turbid water since 1974 and the intensified soil and water conservation since the 1970s, and (5) a slow erosion phase (2000-2007, -0.15km3/y or -6cm/y) in response to the water and sediment regulation and the initial operation of Xiaolangdi reservoir. The total reduction in sediment delivery by this river is 41.0Gt (giga tons) during 1959-2007. The sediment delivery reduction are dams and reservoirs (51%), soil and water conservation (25%), increased water consumption (19%), and channel sedimentation (13%). © 2014 Elsevier B.V.

Wang C.,University of British Columbia | Wang C.,Ocean University of China | Pawlowicz R.,University of British Columbia
Journal of Geophysical Research: Oceans | Year: 2011

A novel aerial observational method for studying internal features in the coastal ocean is developed and tested in a study of large nonlinear internal solitary-like waves. Photogrammetrically rectified oblique photo images from a circling aircraft are used to track a number of internal wave packets for periods of up to one hour in the Strait of Georgia, British Columbia, Canada. Combining these sequences with coincident water column data allows us to obtain a more complete view of the spatial structure of internal waves. Highly accurate measurements of wave propagation speeds and directions are possible. The applicability of various weakly nonlinear theories in modeling propagation of the observed large-amplitude waves is tested. The measured wave speeds enable us to differentiate between classic internal wave models. The linear, KdV (Korteweg-de Vries), and BO (Benjamin-Ono) models are applied with and without background shear. After background shear effects are included, it is found that a continuously stratified BO equation can predict propagation speeds within observational error, and that this is not true for other theories. The technique may be useful in future studies of oblique internal wave interactions. Copyright 2011 by the American Geophysical Union.

Jian M.,Shandong University | Dong J.,Ocean University of China
Multimedia Tools and Applications | Year: 2011

Image fusion is a process that multiple images of a scene are combined to form a single image. The aim of image fusion is to preserve the full content and retain important features of each original image. In this paper, we propose a novel approach based on wavelet transform to capture and fusion of real-world rough surface textures, which are commonly used in multimedia applications and referred to as3D surface texture. These textures are different from 2D textures as their appearances can vary dramatically with different illumination conditions due to complex surface geometry and reflectance properties. In our approach, we first extract gradient/height and albedo maps from sample 3D surface texture images as their representation. Then we measure saliency of wavelet coefficients of these 3D surface texture representations. The saliency values reflect the meaningful content of the wavelet coefficients and are consistent with human visual perception. Finally we fuse the gradient/height and albedo maps based on the measured saliency values. This novel scheme aims to preserve the original texture patterns together with geometry and reflectance characteristics from input images. Experimental results show that the proposed approach can not only capture and fuse 3D surface texture under arbitrary illumination directions, but also has the ability to retain the surface geometry properties and preserve perceptual features in the original images. © Springer Science+Business Media, LLC 2010.

Zhao G.,University of Hong Kong | Li S.,Ocean University of China | Sun M.,University of Hong Kong | Wilde S.A.,Curtin University Australia
International Geology Review | Year: 2011

Columbia is a Palaeo-Mesoproterozoic supercontinent that was assembled during global 2.0-1.8Ga collisional events, underwent long-lived, subduction-related accretion at key continental margins in the period 1.8-1.3Ga, commenced to fragment ∼1.6Ga ago, and finally broke up at ∼1.3Ga. Similar to most other cratonic blocks (Laurentia, Baltica, Siberia, Amazonia, West African, South Africa, India, Australia, and Antarctica), the North China Craton records the history of assembly, accretion, and break-up of the Columbia supercontinent. New data indicate that the Archaean to Palaeoproterozoic basement of the North China Craton was assembled by microcontinental blocks along three Palaeoproterozoic collisional belts: the Khondalite Belt, the Jiao-Liao-Ji Belt, and the Trans-North China Orogen. The Khondalite Belt was formed by collision between the Yinshan and Ordos blocks and was amalgamated to form the Western Block at ∼1.95Ga. The Eastern Block underwent Palaeoproterozoic rifting at 2.2-1.9Ga to break-up into the Longgang and Nangrim blocks; then the rift basin/incipient ocean closed attending subduction and collision to form the Jiao-Liao-Ji Belt at ∼1.9Ga. Finally, the Western and Eastern blocks collided along the Trans-North China Orogen to form the coherent basement of the North China Craton at ∼1.85Ga. Following this final assembly, the North China Craton underwent subduction-related accretion at its southern margin during the period 1.78-1.45Ga, forming the Xiong'er volcanic belt. At 1.6-1.2Ga, the northern margin of the North China Craton underwent a rifting event that led to separation of the craton from other cratonic blocks of the supercontinent Columbia, forming the 1.6-1.2Ga Zhaertai-Bayan Obo rift zone and associated 1.35Ga mafic sills along the northern margin of the craton. These data indicate that in any configuration of Columbia, the southern margin of the North China Craton must have faced an open ocean, whereas its northern margin was connected to another continental block. © 2011 Taylor & Francis.

Wang S.,Ocean University of China
Inverse Problems in Science and Engineering | Year: 2014

Development of efficient model-updating and parameter estimation techniques is of great importance for civil structures. The present paper extends a recently developed cross-model cross-mode (CMCM) method for model updating and parameter estimation, when connectivity flexibility and boundary conditions are incorporated. First, the stiffness matrix of a beam member with semi-rigid joints at both ends is formulated, where the semi-rigid joints enable connections to be modelled as partially restrained. Second, boundary substructure elements are used to capture the stiffness and mass properties of the foundation. Finally, the model updating and parameter estimation of connection flexibility and boundary conditions are incorporated into the CMCM method. To validate the capability and effectiveness of the developed algorithm, numerical studies are conducted on a 2D bridge structure based on data generated from finite-element models. Numerical results demonstrate that the present method is effective for model updating and parameter estimation, when incorporating connectivity flexibility and boundary conditions. © 2013 © 2013 Taylor & Francis.

Xu Z.,Ocean University of China | Xu Z.,Texas A&M University | Chang P.,Texas A&M University | Richter I.,Japan Agency for Marine - Earth Science and Technology | And 2 more authors.
Climate Dynamics | Year: 2014

Warm sea-surface temperature (SST) biases in the southeastern tropical Atlantic (SETA), which is defined by a region from 5°E to the west coast of southern Africa and from 10°S to 30°S, are a common problem in many current and previous generation climate models. The Coupled Model Intercomparison Project Phase 5 (CMIP5) ensemble provides a useful framework to tackle the complex issues concerning causes of the SST bias. In this study, we tested a number of previously proposed mechanisms responsible for the SETA SST bias and found the following results. First, the multi-model ensemble mean shows a positive shortwave radiation bias of ~20 W m−2, consistent with models’ deficiency in simulating low-level clouds. This shortwave radiation error, however, is overwhelmed by larger errors in the simulated surface turbulent heat and longwave radiation fluxes, resulting in excessive heat loss from the ocean. The result holds for atmosphere-only model simulations from the same multi-model ensemble, where the effect of SST biases on surface heat fluxes is removed, and is not sensitive to whether the analysis region is chosen to coincide with the maximum warm SST bias along the coast or with the main SETA stratocumulus deck away from the coast. This combined with the fact that there is no statistically significant relationship between simulated SST biases and surface heat flux biases among CMIP5 models suggests that the shortwave radiation bias caused by poorly simulated low-level clouds is not the leading cause of the warm SST bias. Second, the majority of CMIP5 models underestimate upwelling strength along the Benguela coast, which is linked to the unrealistically weak alongshore wind stress simulated by the models. However, a correlation analysis between the model simulated vertical velocities and SST biases does not reveal a statistically significant relationship between the two, suggesting that the deficient coastal upwelling in the models is not simply related to the warm SST bias via vertical heat advection. Third, SETA SST biases in CMIP5 models are correlated with surface and subsurface ocean temperature biases in the equatorial region, suggesting that the equatorial temperature bias remotely contributes to the SETA SST bias. Finally, we found that all CMIP5 models simulate a southward displaced Angola–Benguela front (ABF), which in many models is more than 10° south of its observed location. Furthermore, SETA SST biases are most significantly correlated with ABF latitude, which suggests that the inability of CMIP5 models to accurately simulate the ABF is a leading cause of the SETA SST bias. This is supported by simulations with the oceanic component of one of the CMIP5 models, which is forced with observationally derived surface fluxes. The results show that even with the observationally derived surface atmospheric forcing, the ocean model generates a significant warm SST bias near the ABF, underlining the important role of ocean dynamics in SETA SST bias problem. Further model simulations were conducted to address the impact of the SETA SST biases. The results indicate a significant remote influence of the SETA SST bias on global model simulations of tropical climate, underscoring the importance and urgency to reduce the SETA SST bias in global climate models. © 2014, Springer-Verlag Berlin Heidelberg.

Liu W.,Yale University | Liu W.,Ocean University of China | Draheim K.M.,Yale University | Zhang R.,Yale University | And 2 more authors.
Molecular Cell | Year: 2013

KRIT1 (Krev/Rap1 Interaction Trapped-1) mutations are observed in ~40% of autosomal-dominant cerebral cavernous malformations (CCMs), a disease occurring in up to 0.5% of the population. We show that KRIT1 functions as a switch for β1 integrin activation by antagonizing ICAP1 (Integrin Cytoplasmic Associated Protein-1)-mediated modulation of " inside-out" activation. We present cocrystal structures of KRIT1 with ICAP1 and ICAP1 with integrin β1 cytoplasmic tail to 2.54 and 3.0 å resolution (the resolutions at which I/σ. I = 2 are 2.75 and 3.0 å, respectively). We find that KRIT1 binds ICAP1 by a bidentate surface, that KRIT1 directly competes with integrin β1 to bind ICAP1, and that KRIT1 antagonizes ICAP1-modulated integrin activation using this site. We also find that KRIT1 contains an N-terminal Nudix domain, in a region previously designated as unstructured. We therefore provide insights to integrin regulation and CCM-associated KRIT1 function. © 2013 Elsevier Inc..

Yao X.H.,Ocean University of China | Zhang L.,Environment Canada
Journal of Geophysical Research: Atmospheres | Year: 2011

Sulfate formation and growth in the various modes of ultrafine particles were explored using samples collected at seven inland rural sites and a remote coastal site in Canada. Two concentration regimes demarcated at a value of 0.03 μg m-3 were identified for nucleation-mode (aerodynamic diameter <0.05 mm) sulfate. In the ≥0.03 μg m-3 regime at the inland sites, strong nucleation of sulfate particles from the enhanced chemical conversion of SO2 to gaseous sulfuric acid was evident, as supported by the moderate to good correlations between the nucleation-mode sulfate and the ambient SO2 concentration as well as the elevated concentrations of O3 and NOy. However, the nucleation- and Aitken-mode sulfate did not correlate with SO2 in the ≥0.03 μg m -3 regime at the coastal site. At the sites where the ≥0.03 μg m-3 regime occurred frequently, the Aitken-mode (aerodynamic diameter 0.05-0.1 μm) sulfate was mainly from the growth of nucleation mode; the condensational growth is found to be more important than the coagulation growth at inland sites, but the coagulation growth became more important at the coastal site. The equivalent ratios of NH4 + to (SO 4 2- + NO3 -) during high-concentration episodes varied from 0.7 to 1.5 in the nucleation mode and were almost unity in the Aitken mode. The equivalent ratio in the nucleation mode ranged from 1.2 to 1.5 at a few inland sites, suggesting that ammonium organic acid salts could be present and could play important roles in the growth of the nucleation-mode particles, but they were unlikely important in the growth of the Aitken mode particles Copyright 2011 by the American Geophysical Union.

Sun H.,Ocean University of China | Wang Q.,CAS Qingdao Institute of Oceanology
Journal of Oceanography | Year: 2016

A general pattern for turbulent mixing in the upper layer of the South China Sea (SCS) is presented based on TurboMAP measurements in April and May 2010. The turbulence level decreased significantly overall from north to south, and weakened from east to west in the northern SCS. The average dissipation rate north of 18°N reaches 1.69 × 10−8 W/kg, approximately six times larger than that south of 18°N. The mean mixing efficiency in the SCS is 0.2, with a maximum of 0.31 near the Luzon Strait. At one repeatedly occupied station located in the central deep basin, the dissipation rate varies diurnally in the mixed layer and pycnocline due to diurnal heating and cooling by solar radiation and local barotropic tide, respectively. © 2016 The Oceanographic Society of Japan and Springer Japan

Chen J.,Ocean University of China | Chen J.,CAS Qingdao Institute of Oceanology
Environmental Monitoring and Assessment | Year: 2014

The accuracy and noise tolerance of 13 global models and 5 Case II chlorophyll a (chl a) retrieval models were evaluated using three dataset. It was found that if 5 % input noise related to atmospheric correction is considered, then the uncertainty associated with noise tolerance varied from 5.5 % to 55.6 %, and these uncertainties generally accounts for 15.63 % to 24.75 % of the total uncertainty. This observation suggests that an optimal algorithm not only should have a strong chl a concentration prediction ability but also should possess high insensitivity to the noise of remote-sensing imagery. The accuracy evaluations of chl a models were based on comparisons of chl a predicted models with chl a concentration measured analytically for field measurements. The results indicate that none of the selected chl a estimation algorithms provide accurate retrievals of chl a in turbid waters. This may be attributed to the strong optical influence of organic and inorganic matter at the blue green range, and the non-negligible of non-organic matter absorption at the red and near-infrared ranges. In order to solve this problem, the chl a concentration retrieval models must be further optimized. After being optimized using the empirical optimized method constructed in this paper, a single parameterized NDCI (normalized difference chl a index) model produces accurate retrievals in the Yellow River Estuary, Taihu Lake and Chesapeake Bay. If 5 % input noise associated with residual uncertainty 0of atmospheric correction is taken into account, the model produces only 29.96 % uncertainty for the remote sensing of chl a concentration in these three turbid waters. © 2013 Springer Science+Business Media.

Lu Z.,Shaoxing University | Wan G.,University of Texas M. D. Anderson Cancer Center | Guo H.,Ocean University of China | Zhang X.,University of Texas M. D. Anderson Cancer Center | Lu X.,University of Texas M. D. Anderson Cancer Center
Cellular Signalling | Year: 2013

The activation and stabilization of the p53 protein play a major role in the DNA damage response. Protein levels of p53 are tightly controlled by transcriptional regulation and a number of positive and negative posttranslational modifiers, including kinases, phosphatases, E3 ubiquitin ligases, deubiquitinases, acetylases and deacetylases. One of the primary p53 regulators is Mdmx. Despite its RING domain and structural similarity with Mdm2, Mdmx does not have an intrinsic ligase activity, but inhibits the transcriptional activity of p53. Previous studies reported that Mdmx is phosphorylated and destabilized in response to DNA damage stress. Three phosphorylation sites identified are Ser342, Ser367, and Ser403. In the present study, we identify protein phosphatase 1 (PP1) as a negative regulator in the p53 signaling pathway. PP1 directly interacts with Mdmx and specifically dephosphorylates Mdmx at Ser367. The dephosphorylation of Mdmx increases its stability and thereby inhibits p53 activity. Our results suggest that PP1 is a crucial component in the ATM-Chk2-p53 signaling pathway. © 2012 Elsevier Inc.

Xie S.-S.,Ocean University of China | Yi S.-C.,Changwon National University | Kwon T.I.,Changwon National University
Computer Physics Communications | Year: 2012

In this paper, two- and three-level compact difference and alternating direction implicit schemes are presented for the numerical solutions of one- and two-dimensional linear telegraph equations and telegraph equations with nonlinear forcing term. The stability and error estimates are given. The convergence rates of the present schemes are of order O( τ2+ h4). Numerical experiments on model problems show that the present schemes are of high accuracy. © 2011 Elsevier B.V.

Jiang T.,Nanjing Medical University | Yu J.-T.,Nanjing Medical University | Yu J.-T.,Qingdao University | Yu J.-T.,Ocean University of China
Journal of Alzheimer's Disease | Year: 2012

Alzheimer's disease (AD) is the most common progressive dementia in the elderly and places an enormous burden on the individual and society. Presently, the treatments for AD are only symptomatic and do not halt the progression of the disease. With the recent advances in the understanding of the pathogenesis of AD in past years, numerous therapies which could modify the disease process are under active investigation. These therapies could attenuate or even reverse the neurodegenerative process by interfering with the underlying pathogenesis including amyloid-β production, tau hyperphosphorylation, oxidative stress, inflammation, and excitotoxicity. In this review, new disease-modifying therapies which reduce amyloid-β production, prevent tau hyperphosphorylation, and provide neuroprotective effects are described, including the results of in vitro and in vivo studies and clinical trials. Some typical therapies with disease-modifying effects have also been discussed. © 2012-IOS Press and the authors. All rights reserved.

Kou B.,State Key Laboratory of Coordination Chemistry | Kou B.,Nanjing Institute of Technology | Guo X.,State Key Laboratory of Coordination Chemistry | Xiao S.-J.,State Key Laboratory of Coordination Chemistry | Liang X.,Ocean University of China
Small | Year: 2013

Artificial DNA tethering azobenzene through a backbone-inserted glycerol via an ether bond is synthesized. The stabilization effect of the hybrid duplex with a native complementary strand of DNA for R-glycerol-inserted DNA is demonstrated even when the molar ratio of azobenzene to nucleotide is 1:2. The half-lives of tens of hours for glycerol-tethered cis-azobenzene and the rapid and highly efficient trans-to-cis photoisomerization in the hybrid DNA duplex at room temperature render the manipulation of DNA nanodevices and functionalities by photoregulation in a green system possible. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Wang Y.-M.,TU Munich | Shen Y.-L.,Ocean University of China
Nuclear Physics B | Year: 2015

We compute perturbative corrections to B→π form factors from QCD light-cone sum rules with B-meson distribution amplitudes. Applying the method of regions we demonstrate factorization of the vacuum-to-B-meson correlation function defined with an interpolating current for pion, at one-loop level, explicitly in the heavy quark limit. The short-distance functions in the factorization formulae of the correlation function involves both hard and hard-collinear scales; and these functions can be further factorized into hard coefficients by integrating out the hard fluctuations and jet functions encoding the hard-collinear information. Resummation of large logarithms in the short-distance functions is then achieved via the standard renormalization-group approach. We further show that structures of the factorization formulae for fBπ+(q2) and fBπ0(q2) at large hadronic recoil from QCD light-cone sum rules match that derived in QCD factorization. In particular, we perform an exploratory phenomenological analysis of B→π form factors, paying attention to various sources of perturbative and systematic uncertainties, and extract |Vub|=(3.05-0.38+0.54|th.±0.09|exp.)×10-3 with the inverse moment of the B-meson distribution amplitude ϕB+(ω) determined by reproducing fBπ+(q2=0) obtained from the light-cone sum rules with π distribution amplitudes. Furthermore, we present the invariant-mass distributions of the lepton pair for B→πℓν (ℓ=μ, τ) in the whole kinematic region. Finally, we discuss non-valence Fock state contributions to the B→π form factors fBπ+(q2) and fBπ0(q2) in brief. © 2015 The Authors.

Liu F.,Ocean University of China
Journal of Sound and Vibration | Year: 2011

A direct estimation method for expanding incomplete experimental mode shapes is presented. The approach adopts a hybrid vector which includes measured data at master degrees of freedom (dofs) and constant values at slave dofs. The constant values are refined by a set of mode-correction factors. Modelling errors between the analytical model and tested structure are also considered by introducing a series of model-correction factors. Initial-guess values of the mode-correction factors are used to decouple the coupled constructed equations, and an iterative technique for solving these equations is proposed. The results from a five-degree-of-freedom massspring system indicate that the proposed approach provided a better performance than the commonly used existing expansion methods and can reliably estimate unmeasured components of mode shapes, even in cases with limited modal measurements and severe measurement noise. The performance of the proposed method was also investigated using real measurements from a steel cantilever-beam experiment. Experimental data were measured by 20 accelerometers mounted at the cantilever beam: among these accelerometers, three of these were assumed to be measured, and the others were used to check the estimation accuracy of the proposed method. The results show that the unmeasured components in the mode shapes were properly estimated by implementing the proposed method, even for high-frequency modes. © 2011 Elsevier Ltd. All rights reserved.

Liu X.,Tongji University | Wu D.,Tongji University | Wang H.,Ocean University of China | Wang Q.,Tongji University
Advanced Materials | Year: 2014

A self-recovering gel with integrated functions synthesized via self-initiated UV polymerization is described. It offers an effective platform for a gel electrolyte to attain adjustable supercapacitor performances for energy-storage devices. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Li J.,Korea University | Lee I.W.,Korea University | Shin G.H.,Korea University | Chen X.,Ocean University of China | Park H.J.,Korea University
European Journal of Pharmaceutics and Biopharmaceutics | Year: 2015

Using a simple solution mixing method, curcumin was dispersed in the matrix of Eudragit® E PO polymer. Water solubility of curcumin in curcumin-Eudragit® E PO solid dispersion (Cur@EPO) was greatly increased. Based on the results of several tests, curcumin was demonstrated to exist in the polymer matrix in amorphous state. The interaction between curcumin and the polymer was investigated through Fourier transform infrared spectroscopy and 1H NMR which implied that OH group of curcumin and carbonyl group of the polymer involved in the H bonding formation. Cur@EPO also provided protection function for curcumin as verified by the pH challenge and UV irradiation test. The pH value influenced curcumin release profile in which sustained release pattern was revealed. Additionally, in vitro transdermal test was conducted to assess the potential of Cur@EPO as a vehicle to deliver curcumin through this alternative administration route. © 2015 Elsevier B.V. All rights reserved.

Meng X.-H.,CAS Institute of Botany | Meng X.-H.,Ocean University of China | Qin G.-Z.,CAS Institute of Botany | Tian S.-P.,CAS Institute of Botany
LWT - Food Science and Technology | Year: 2010

The effects of preharvest spray with Cryptococcus laurentii combined with chitosan coating after harvest on decay and quality of table grapes during storage periods were evaluated in the present study. Preharvest spray with C. laurentii (PreA) significantly decreased decay index (DI), and postharvest chitosan coating (PCC) enhanced the effectiveness of the pre-harvest spray when fruits were stored at 0 °C. PreA combination with PCC increased the activities of polyphenol oxidase (PPO) and phenylalanine ammonia-lyase (PAL) of fruit in storage. PreA + PCC treatment was effective in reducing weight loss of fruits by 85% at 17 d storage and 38% at 42 d storage as compared to PreA alone at the same stage. In addition, PreA enhanced the ratio of soluble solids content (SSC) to titratable acid (TA) by 12% at harvest time, 7% at 17 d storage and 25% at 42 d storage, mainly by increasing SSC and decreasing TA in fruit stored at 0 °C. These results suggested that integration of preharvest spray with C. laurentii and postharvest chitosan coating treatment may be a promising management strategy for decay control and quality maintenance of table grapes. © 2009 Elsevier Ltd. All rights reserved.

Huang Y.,Liaocheng University | Zhang Z.,Ocean University of China
Journal of the Marine Biological Association of the United Kingdom | Year: 2010

Two new species of free-living marine nematodes, Daptonema longiapophysis sp. nov. and Cobbia sinica sp. nov. from the Yellow Sea, China are described and illustrated. Daptonema longiapophysis sp. nov. is characterized by spicules with a projection on the ventral and dorsal side respectively and the length of the gubernacular apophysis longer than the length of spicules. Cobbia sinica sp. nov. is characterized by one big dorsal tooth, long conico-cylindrical tail and gubernaculum with a small dorsal apophysis. Copyright © Marine Biological Association of the United Kingdom 2010.

The defence ability of Fenneropenaeus chinensis and Marsupenaeus japonicus against the intrusion of the white spot syndrome virus (WSSV) was compared after injecting WSSV intramuscularly by recording cumulative mortality, diagnosing the virus and examining variations in immunological parameters including the total haemocyte counts (THCs), phagocytic percentage (PP), plasma protein concentration (PPC), phenoloxidase (PO) and nitric oxide synthase (NOS) activity. The results showed that the variations in the immunological parameters of F. chinensis and M. japonicus showed similar trends. The THCs of the two species decreased significantly postchallenge of WSSV. The virus was detected at 78 h in M. japonicus and at 42 h in F. chinensis after infection, which was in correlation with the accumulative mortality, and the variations in PO, NOS and PPC in the two species. All shrimps of F. chinensis in the mortality experiment died within 66 h, much more quickly than M. japonicus, whose cumulative mortality reached 100% after 198 h. In conclusion, the immune system of M. japonicus has a stronger resistant ability to antagonize and endure the invasion of WSSV than that of F. chinensis. © 2009 The Authors. Journal Compilation © 2009 Blackwell Publishing Ltd.

Popuri S.R.,The University of the West Indies, Cave Hill Campus | Chang C.-Y.,Chia Nan University of Pharmacy and Science | Xu J.,Ocean University of China
Desalination | Year: 2011

The feasibility of treating acrylonitrile-butadiene-styrene (ABS) resin manufacturing wastewater by Fenton oxidation treatment was investigated. The experiments were conducted in six different operating modes. For all tests, total dosage of ferrous (Fe2+) salt and hydrogen peroxide (H2O2) was kept at 2000mg L-1 and 4000mg L-1, respectively and the total reaction time was maintained at 160min. The kinetics of the decomposition of organic matter in terms of dissolved chemical oxygen demand (DCOD) by H2O2 followed the pseudo-first order reaction. For DCOD decomposition, the removal rate constant equation of DCOD, k1=2.95×10-6[H2O2]0 0.17[Fe2+]0 1.60 was obtained, where k1 is the reaction rate coefficient of DOCD decomposition. The consumption rate constant equation of H2O2, k2=1.85×10-3[H2O2]0 -1.70[Fe2+]0 2.90 was obtained, where k2 is the reaction rate coefficient of hydrogen peroxide consumption. Batch and semi-batch studies indicated that oxidation with Fenton's reagent is feasible for treating ABS wastewater. © 2011 Elsevier B.V.

Trucu D.,University of Dundee | Lin P.,University of Dundee | Chaplain M.A.J.,University of Dundee | Wang Y.,Ocean University of China
Multiscale Modeling and Simulation | Year: 2013

Cancer invasion of tissue is a key aspect of the growth and spread of cancer and is crucial in the process of metastatic spread, i.e., the growth of secondary cancers. Invasion consists in cancer cells secreting various matrix degrading enzymes (MDEs) which destroy the surrounding tissue or extracellular matrix (ECM). Through a combination of proliferation and migration, the cancer cells then actively spread locally into the surrounding tissue. Thus processes occurring at the level of individual cells eventually give rise to processes occurring at the tissue level. In this paper we introduce a new type of multiscale model describing the process of cancer invasion of tissue. Our multiscale model is a two-scale model which focuses on the macroscopic dynamics of the distributions of cancer cells and of the surrounding extracellular matrix, and on the microscale dynamics of the MDEs, produced at the level of the individual cancer cells. These microscale dynamics take place at the interface of the cancer cells and the ECM and give rise to a moving boundary at the macroscale. On the computational side, in order to approximate the newly proposed model, we have developed a novel computational scheme based on a combination of finite elements at the microscale with a new finite difference technique at the macroscale, linking together in a moving boundary formulation of the problem. This two-scale numerical scheme is organized in such a way that it enables us to accurately model all the key processes of cancer invasion at both the macroscale and microscale. © 2013 Society for Industrial and Applied Mathematics.

Li C.,Ocean University of China | Ma H.,Zhejiang Province Climate Center
Advances in Atmospheric Sciences | Year: 2012

In this study, the relationship between El Niño-Southern Oscillation (ENSO) and winter rainfall over Southeast China (SC) is demonstrated based on instrumental and reanalysis data. The results show that ENSO and SC winter rainfall (ENSO-SC rainfall) are highly correlated and intimately coupled through an anomalous high pressure over the northwestern Pacific. In mature phase, El Niño (La Niña) events can cause more (less) rainfall over SC in winter. Due to the persistence and spring barrier of ENSO, SC winter rainfall has potential predictability of about half a year ahead with ENSO as a predictor. Besides, the ENSO-SC rainfall relationship exhibits decadal variability, closer before the early 1970s (0. 47) and after the early 1990s (0. 76), but weaker (0. 12) between these times. In different periods, atmospheric teleconnection patterns have large differences and the predictability of SC winter rainfall also changes dramatically. For the most recent 20 years, the ENSO-SC rainfall relationship is closest and the prediction of SC winter rainfall anomalies based on ENSO is most creditable. In addition, the causes and mechanisms of the decadal modulation of the relationship between ENSO and SC winter rainfall need to be further studied. © 2012 Chinese National Committee for International Association of Meteorology and Atmospheric Sciences, Institute of Atmospheric Physics, Science Press and Springer-Verlag Berlin Heidelberg.

Tam P.Y.,University of Hong Kong | Zhao G.,University of Hong Kong | Sun M.,University of Hong Kong | Li S.,Ocean University of China | And 5 more authors.
Precambrian Research | Year: 2012

Both medium- and high-pressure pelitic granulites were found in the Jiaobei massif in the southern segment of the Jiao-Liao-Ji Belt, which is a Paleoproterozoic tectonic belt in the Eastern Block of the North China Craton. Studies on mineral assemblages and metamorphic reaction textures reveal that the medium-pressure pelitic granulites from the Jiaobei massif underwent four metamorphic stages: (1) the prograde stage (M1) represented by mineral inclusions within the core of garnet grains; (2) the peak stage (M2) indicated by the formation of sillimanite. +. K-feldspar and the growth of inclusion-free garnet mantle, (3) the decompression stage (M3) characterized by the cordierite. +. sillimanite symplectite, and (4) the decompression-cooling stage (M4) forming cordierite coronas. An integrated study of mineral reaction textures, mineral chemistry and pseudosection modelling in the NCFKMASHTO system with the THERMOCALC technique constrains the P-. T conditions of 9.4-10. kbar and 870-900. °C for the M2 stage, 6.3-6.6. kbar and 840-900. °C for the M3 stage, and 4-5.2. kbar and 815-830. °C for the M4 stage. The P-. T conditions of the early prograde (M1) assemblage cannot be estimated due to reworking at later metamorphic stages (M2-M4). The mineral assemblages of the M2-M4 stages and their P-. T conditions define a clockwise P-. T path involving isothermal decompression (ITD) and subsequent decompression-cooling for the medium-pressure pelitic granulites, which are consistent with a continent-continent collision environment. This suggests that the Jiao-Liao-Ji Belt was not formed simply by the closure of a Paleoproterozoic rift basin as conventionally considered, but the tectonic evolution of its southern segment must have been involved in subduction and/or continent-continent collisional processes. Based on this study and previous data, we propose that the Jiao-Liao-Ji Belt represented a Paleoproterozoic rifting- and collision-belt along which the Langgang and Langrim Blocks amalgamated to form the Eastern Block of the North China Craton. © 2012 Elsevier B.V.

Guo H.,Hong Kong Polytechnic University | Wang D.W.,Hong Kong Polytechnic University | Cheung K.,Hong Kong Polytechnic University | Ling Z.H.,Hong Kong Polytechnic University | And 2 more authors.
Atmospheric Chemistry and Physics | Year: 2012

In order to investigate the formation and growth processes of nucleation mode particles, and to quantify the particle number (PN) concentration and size distributions in Hong Kong, an intensive field measurement was conducted from 25 October to 29 November in 2010 near the mountain summit of Tai Mo Shan, a suburban site approximately the geographical centre of the New Territories in Hong Kong. Based on observations of the particle size distribution, new particle formation (NPF) events were found on 12 out of 35 days with the estimated formation rate J 5.5 from 0.97 to 10.2 cm -3 s -1, and the average growth rates from 1.5 to 8.4 nm h -1. The events usually began at 10:00-11:00 LT characterized by the occurrence of a nucleation mode with a peak diameter of 6-10 nm. Solar radiation, wind speed, sulfur dioxide (SO 2) and ozone (O3) concentrations were on average higher, whereas temperature, relative humidity and daytime nitrogen dioxide (NO 2) concentration were lower on NPF days than on non-NPF days. Back trajectory analysis suggested that in majority of the NPF event days, the air masses originated from the northwest to northeast directions. The concentrations of gaseous sulfuric acid (SA) showed good power-law relationship with formation rates, with exponents ranging from 1 to 2. The result suggests that the cluster activation theory and kinetic nucleation could potentially explain the observed NPF events in this mountainous atmosphere of Hong Kong. Meanwhile, in these NPF events, the contribution of sulfuric acid vapor to particle growth rate (GR 5.5-25) ranged from 9.2 to 52.5% with an average of 26%. Measurement-based calculated oxidation rates of monoterpenes (i.e. α-pinene, β-pinene, myrcene and limonene) by O3 positively correlated with the GR 5.5-25 (R= 0.80, p < 0.05). The observed associations of the estimated formation rate J 5.5 and the growth rate GR 5.5-25 with gaseous sulfuric acid and volatile organic compounds (VOCs) suggested the critical roles of sulfuric acid and biogenic VOCs (e.g. α-pinene and β-pinene) in these NPF events. © 2012 Author(s).

Zhang J.,University of Hong Kong | Zhao G.,University of Hong Kong | Li S.,Ocean University of China | Sun M.,University of Hong Kong | And 3 more authors.
Precambrian Research | Year: 2012

Wutai Complex is a key to test controversial models for the tectonic evolution of the Trans-North China Orogen (TNCO), along which the Eastern and Western Blocks amalgamated to form the North China Craton. Three stages of deformation (D1 to D3) were identified in the Wutai Complex. D1 is characterized by NE-SW-trending foliations S1 and NW-SE-orientated lineations L1, indicating an initial NW-SE-directed compression. Associated with D1 was prograde metamorphism (M1). D2 progressively overprinted D1 and generated 'Z'-shaped folds and NEE-SWW-trending ductile shear zones. D2 resulted in a fan-shaped structural pattern of the complex with top-to-the-NW thrusting in the northwestern part and opposite top-to-the-SE thrusting in the southeastern part. During D2, the crust was doubled through thickening, leading to peak metamorphism (M2). D3 developed during post-collision exhumation and deformed the early fabrics to be open folds, resulting in near-isothermal decompression (M3) and late cooling metamorphism (M4). The overall structure of the Wutai Complex is characterized by a fan-shaped pattern with structural divergence. Structural features of the Wutai Complex, combined with those of the adjacent Hengshan and Fuping Complexes, indicate that the TNCO is characterized by a fan-shaped orogenic wedge with opposite senses of thrust. This orogenic wedge could have resulted from an eastward subduction and collision between the Western and Eastern Blocks to finally form the TNCO at ~1.85Ga. © 2011 Elsevier B.V.

Wu M.,University of Hong Kong | Zhao G.,University of Hong Kong | Sun M.,University of Hong Kong | Yin C.,University of Hong Kong | And 2 more authors.
Precambrian Research | Year: 2012

Mafic granulites from the Yishui Group of the Western Shandong Complex in the Eastern Block of the North China Craton occur as enclaves or boudins within Late Archean TTG gneisses, and are composed mainly of garnet, clinopyroxene, orthopyroxene, plagioclase, hornblende, and minor quartz, ilmenite, and magnetite. Petrographic examination has revealed three distinct metamorphic mineral assemblages: the pre-peak prograde assemblage (M1) of hornblende+plagioclase+quartz+ilmenite+magnetite occurring as inclusions within garnet and pyroxene grains, peak assemblage (M2) of orthopyroxene+clinopyroxene+plagioclase+garnet+hornblende+quartz+ilmenite+magnetite, and post-peak assemblage (M3) represented by garnet+quartz and garnet+ilmenite/magnetite symplectites. Pseudosection modeling using THERMOCALC in the NCFMASHTO model system for a representative sample constrains the P-T conditions of M1, M2 and M3 stages at 660-730°C/<6.6kbar, 800-820°C/8.0-8.5kbar and 686-710°C/7.6-8.6kbar, respectively. The results of petrology and quantitative P-T pseudosection modeling define an anticlockwise P-T path involving near-isobaric cooling following the peak medium-pressure granulite-facies metamorphism, suggesting that the metamorphism of the Yishui Group was most likely related to the intrusion and underplating of mantle-derived magmas. Although the underplating of voluminous mantle-derived magmas leading to granulite-facies metamorphism with an anticlockwise P-T path involving isobaric cooling may occur in continental magmatic arc regions, above hot spots driven by mantle plumes, or in continental rift environments, a mantle plume model is favored because this model can reasonably interpret many other geological features of Late Archean basement rocks from the Western Shandong Complex in the Eastern Block of the North China Craton as well as their anticlockwise P-T paths involving isobaric cooling. The relatively cooler mantle-plume head heated the crust initially, causing amphibolite-facies metamorphism (M1). Subsequently, the relatively hotter mantle-plume tail heated the crust, causing granulite-facies metamorphism (M2). Finally, a near-isobaric cooling process (M3) occurred when the mantle plume ceased to heat the crust. © 2011 Elsevier B.V.

Shi X.,Hangzhou Normal University | Liu X.,Hangzhou Normal University | Liu G.,Hangzhou Normal University | Sun Z.,Hangzhou Normal University | Xu H.,Ocean University of China
Environmental Science and Pollution Research | Year: 2012

Introduction: In order to evaluate water quality of a canal system, the spatial pattern of protozoan communities in response to physicochemical variables was studied in the Hangzhou section of the Grand Canal, northern China during a 1-year cycle (February 2008-January 2009). Materials and methods: Protozoan samples were monthly collected at six sampling stations with a spatial gradient of environmental status. Physicochemical parameters, e. g., water temperature, dissolved oxygen, chemical oxygen demand (COD), biological oxygen demand, total nitrogen (TN), and total phosphorus (TP), were measured synchronously for comparison with biotic parameters. Results: The protozoan community structures represented significant differences among the six sampling stations. The spatial patterns of protozoan communities were significantly correlated with the changes of chemical variables, especially COD, either alone or in combination with TP and/or TN. Of 88 protozoan taxa recorded over the study period, ten species (e. g., Carchesium polypinum, Colpidium campylum, Prorodon teres, Vorticella putrina, Zoothamnium arbuscula, Euglena spp., and Phacus spp.) were significantly related to COD, either alone or in combination with TP and/or TN. Conclusion: These findings suggest that protozoa can be used as a robust bioindicator of water quality in freshwater river systems. © 2011 Springer-Verlag.

Brzozowska R.,University of Warmia and Mazury | Sui Z.,Ocean University of China | Kang K.H.,Chonnam National University
Ecological Engineering | Year: 2012

The aim of the present study has been to analyze the effect of Mytilus sp. on the quality of raw seawater (organic compounds and heavy metals concentrations). The experiment was conducted under laboratory conditions. Two groups of the sea mussel were used in the experiments: small (S group; mean shell length 28.54 ± 1.69 mm) and large ones (L group; mean shell length 35.07 ± 1.83 mm). The highest removal efficiency of organic compounds, Zn, Pb and Ni was observed for the water retention time in a reactor of 9 or 12 h. The differences between removal efficiencies of COD, Zn, Pb and Ni were significant and mainly dependent on the water retention time, less - on the mussels' size (two-way ANOVA, p< 0.05). Unlike the other examined heavy metals, Cr revealed no significant concentration changes, which may suggest that sea mussels are unable to remove Cr from seawater quickly. The results suggest that it might be possible to use Mytilus sp. as a kind of biofilter for the improvement of seawater quality. © 2011 Elsevier B.V.

Han W.,North University of China | Liu Y.,Hebei Normal University of Science and Technology | Wang L.,Ocean University of China
Neural Computing and Applications | Year: 2012

This paper deals with the global exponential stability in the mean square of fuzzy cellular neural networks with time-varying delays and Markovian jumping parameters. By constructing suitable Lyapunov functionals, we obtain several sufficient conditions which can be expressed in terms of linear matrix inequalities (LMIs). The proposed LMI results are computationally efficient as it can be solved numerically by using Matlab LMI toolbox. An example is given to show the effectiveness of the results. © 2011 Springer-Verlag London Limited.

Tam P.Y.,University of Hong Kong | Zhao G.,University of Hong Kong | Sun M.,University of Hong Kong | Li S.,Ocean University of China | And 2 more authors.
Lithos | Year: 2012

High-pressure mafic granulites from the Jiaobei massif in the southern segment of the Jiao-Liao-Ji Belt (JLJB) situating in the Eastern Block of the North China Craton (NCC) were examined based on an integrated study of petrology, mineral chemistry and pseudosection modeling. Microstructural relationships of the high-pressure mafic granulites indicate four metamorphic stages, including the pre-peak (M1) stage indicated by garnet core. +. inclusion-phase minerals of hornblende. +. clinopyroxene. +. plagioclase. +. quartz ± epidote ± rutile, the peak (M2) stage featured by garnet mantle/rim. +. matrix-phase minerals of clinopyroxene. +. plagioclase. +. quartz ± rutile, the post-peak (M3) stage characterized by the clinopyroxene. +. plagioclase. +. orthopyroxene symplectite, and the retrograde (M4) stage represented by the hornblende. +. plagioclase symplectite and symplectic clinopyroxene. +. ilmenite. +. quartz. By applying the THERMOCALC (Version 3.33) technique in the NCFMASHTO system, the P-T conditions are estimated at 9.4-9.8. kbar and 690-702 °C for the pre-peak (M1) stage, 13.1-15.1. kbar and 780-890 °C for the peak (M2) stage, 7.8-8.4. kbar and 820-880 °C for the post-peak (M3) stage and the 6.4-7.2. kbar and 690-760 °C for the retrograde (M4) stage. These mineral assemblages and their P-T conditions define a clockwise P-T path for the high-pressure mafic granulites in the Jiaobei massif, suggesting that the rocks underwent near-isothermal decompression and subsequent cooling after the peak metamorphism, which implies that the southern segment of the JLJB must have experienced subduction-/collision-related tectonic processes at ca. 1.93-1.90. Ga. Therefore, the Jiao-Liao-Ji Belt may represent another Paleoproterozoic collisional belt along which the Longgang and Langrim Blocks amalgamated to form the Eastern Block of the North China Craton. © 2012 Elsevier B.V.

Bishop C.A.,Southern Illinois University Carbondale | Ou Y.-C.,Southern Illinois University Carbondale | Wang Z.-M.,Ocean University of China | Byrd M.S.,Southern Illinois University Carbondale
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2010

We provide a class of initial encodings that can be sent with a high fidelity over an unmodulated, linear, XY spin chain. As an example, an average fidelity of 96% can be obtained using an 11-spin encoding to transmit a state over a chain containing 10 000 spins. An analysis of the magnetic-field dependence is given, and conditions for field optimization are provided. © 2010 The American Physical Society.

Song Z.,Ocean University of China | Song Z.,First Institute of Oceanography | Qiao F.,First Institute of Oceanography | Song Y.,First Institute of Oceanography
Journal of Geophysical Research: Oceans | Year: 2012

[1] One of the common problems of the coupled atmosphere-ocean general circulation models (AOGCMs) without flux correction is that the simulated sea surface temperature (SST) deviates noticeably from the observation especially in the tropics, such as the too cold tongue in the eastern Pacific and a reversed SST zonal gradient in the equatorial Atlantic. The coupled atmosphere-wave-ocean general circulation model, which incorporates the non-breaking surface wave-induced mixing into the CCSM3 through a coupler, can improve the simulation of the tropical SST. On the ocean-basin scale, the wave-induced vertical mixing can generate "West-Positive and East-Negative" pattern for the equatorial SST that much alleviates the tropical bias. The formation mechanism for this basin-wide response to the wave-induced mixing is analyzed through sensitive experiments of AOGCMs and stand-alone ocean general circulation models (OGCMs). First, in each basin, the SST becomes colder under the direct effect of the wave-induced mixing, and the SST in the eastern part of each basin is colder due to the shallower ocean mixed layer than that of the western part. The SST in the western basin (or central basin in the Pacific Ocean) increases due to the weakened eastward zonal current. Then, the pattern of warm SST in the west and cold SST in the east is amplified due to the Bjernkes feedback in a climate system. The net heat flux feedback plays a negative role in this kind of SST response. © 2012. American Geophysical Union. All Rights Reserved.

Wang S.,Ocean University of China
Applied Ocean Research | Year: 2013

Development of efficient global damage detection techniques for offshore structures is of great importance. The present paper applies the iterative modal strain energy (IMSE) method to locate and quantify the damage for three dimensional frame structures, when limited, spatially incomplete modal data are available. One theoretical development is a new procedure to directly incorporate the spatially-incomplete mode shapes in the algorithm, where slave degrees of freedom iterative updating procedure (SDUP) is developed for evaluating the damage indicator and damage severity. The merits of this new method are that both the modal frequencies and spatially incomplete mode shapes can be used. Also, the modal frequencies do not need to pair the mode shapes one by one. To demonstrate the feasibility and effectiveness of the developed algorithm, numerical studies are conducted for a 3D offshore platform based on data generated from finite element models. Numerical results demonstrate that the present method is effective for the damage assessment of a 3D frame structures when limited, spatially incomplete modal data are available. After considering more practical factors, it is expected to be more applicable in structural damage assessment. © 2013 Elsevier Ltd.

Wang S.,Ocean University of China
Structural Control and Health Monitoring | Year: 2013

A damage severity estimation method, named as iterative modal strain energy (IMSE) method, is developed to quantify the damage magnitude using the frequency measurements. Although all existing damage quantification methods that utilize modal strain energy are either employing mode shapes from the damage structure or under/overestimating the damage severity, the IMSE method is able to estimate the severity accurately, requiring only a few amount of identified modal frequencies from the damaged structure. To demonstrate the capabilities of the developed damage severity estimation algorithm, numerical studies are conducted of a clamped-free beam based on data generated from finite element models. Both noise-free and noise-polluted cases are considered. Furthermore, experimental data from a tested clamped-free beam are utilized to validate the IMSE method. The results demonstrate that the proposed algorithm is capable of quantifying the damage extent accurately. Copyright © 2011 John Wiley & Sons, Ltd.

Liu W.,Ocean University of China
Dong wu xue yan jiu = Zoological research / "Dong wu xue yan jiu" bian ji wei yuan hui bian ji | Year: 2010

To provide a theoretical basis to improve the survival and growth rate and optimize diet of sheatfish (Silurus soldatovi), the activities of certain digestive enzymes and alkaline phosphatases were investigated during larval development of one-ten day old individuals. Results indicated that sheatfish larva (~ three days after hatching) had high levels of alkaline protease activity, which peaked at five days old and dipped by eight days old, although the trend was generally upward. Acid protease activity at one-eight days old was low, after which it increased rapidly. Amylase activity reached the highest value at five days old, after which it began to decline. Lipase activity fluctuated markedly and showed two peaks at three-four days old and six-eight days old. Larval digestive enzyme activity and alkaline phosphatase activity were higher when fed live food than when fed an artificial diet. Throughout the early development process, alkaline protease activity was higher than acid protease, alkaline protease and amylase specific activity decreased significantly for eight-day-old transition larvae, while acid protease activity increased rapidly. These results indicate that the changes in digestive enzyme activity were relevant to digestive function conversion during fish larvae development. Alkaline phosphatase activity showed an upward trend over the first ten days of life, which indicated that the gastrointestinal function of sheatfish improved gradually.

Ganti V.,California Institute of Technology | Chu Z.,Ocean University of China | Lamb M.P.,California Institute of Technology | Nittrouer J.A.,Rice University | Parker G.,University of Illinois at Urbana - Champaign
Geophysical Research Letters | Year: 2014

A mechanistic understanding of river avulsion location and frequency is needed to predict the growth of alluvial fans and deltas. The Huanghe, China, provides a rare opportunity to test emerging theories because its high sediment load produces regular avulsions at two distinct nodes. Where the river debouches from the Loess Plateau, avulsions occur at an abrupt decrease in bed slope and reoccur at a time interval (607 years) consistent with a channel-filling timescale set by the superelevation height of the levees. Downstream, natural deltaic avulsions reoccur at a timescale that is fast (7 years) compared to channel-filling timescale due to large stage-height variability during floods. Unlike the upstream node, deltaic avulsions cluster at a location influenced by backwater hydrodynamics and show evidence for episodic downstream migration in concert with progradation of the shoreline, providing new expectations for the interplay between avulsion location, frequency, shoreline rugosity, and delta morphology. © 2014. American Geophysical Union. All Rights Reserved.

Zhang L.,Princeton University | Zhang L.,National Oceanic and Atmospheric Administration | Zhao C.,Ocean University of China
Journal of Advances in Modeling Earth Systems | Year: 2015

Almost all of CMIP5 climate models show cold SST biases in the extratropical North Atlantic (ENA) and tropical North Atlantic (TNA) as well as in the North Pacific which are commonly linked with the weak simulated Atlantic meridional overturning circulation (AMOC). A weak AMOC and its associated reduced northward oceanic heat transport are associated with a cooling of the ENA Ocean, whereas the TNA cooling is attributable to both weak AMOC and surface heat flux. The cold biases in the ENA and TNA have remote impacts on the SST bias in the North Pacific. Here we use coupled ocean-atmosphere model experiments to show the mechanisms and pathways by which the ENA and TNA affect the North Pacific. The model simulations demonstrate that the cooling SST bias in the North Pacific is largely due to the remote effect of the cooling SST bias in the ENA, while the remote impact of the TNA cooling SST bias is of secondary importance. The ENA cooling bias triggers the circumglobal teleconnection via the Northern Hemisphere annular mode, producing a strengthening of the Aleutian low, an enhancement of the southward Ekman and Oyashio cold advection, and thus a cooling SST in the North Pacific. In contrast, the TNA cooling produces a surface high extending to the eastern tropical North Pacific, inducing the northeasterly wind anomalies north, northerly cross-equatorial wind anomalies, and northwesterly wind anomalies south of the equator. This C-shape wind anomaly pattern generates an SST warming in the tropical southeastern Pacific, which eventually leads to an SST warming in the tropical central and western Pacific by the wind-evaporation-SST feedback. The tropical Pacific warming in turn leads to an SST cooling in the North Pacific by the Pacific North American teleconnection pattern. © 2015. The Authors.

Yin L.,Ocean University of China | Qiao F.,State Oceanic Administration | Zheng Q.,University of Maryland College Park
Journal of Physical Oceanography | Year: 2014

Using five mooring array observations in the coastal water of the East China Sea (ECS) in winter 2006, the authors identify three kinds of low-frequency waves using the ensemble empirical mode decomposition (EEMD) method. The analysis indicates that the periods of the waves varied from 2 to 10 days, which are consistent with coastal-trapped wave (CTW) modes: the Kelvin wave (KW) mode, the first shelf wave (SW1) mode, and the second shelf wave (SW2) mode. An analytical model is established and the dispersion relation of the waves from the analytical method agrees well with the observations. The wind-forced, coastal-trapped wave theory is then applied. The calculation shows that over a wide shelf, the forcing term of wind stress curl plays an important role in shaping the CTW. Numerical solutions reproduce the sea level variation and the alongshore current. The results show that the sea level variation mainly resulted from the KW mode, but the alongshore current resulted from both the KW and SW1 modes. © 2014 American Meteorological Society.

Li G.,CAS South China Sea Institute of Oceanology | Li G.,University of Hawaii at Manoa | Li G.,University of California at San Diego | Xie S.-P.,University of Hawaii at Manoa | And 2 more authors.
Journal of Climate | Year: 2014

Errors of coupled general circulation models (CGCMs) limit their utility for climate prediction and projection. Origins of and feedback for tropical biases are investigated in the historical climate simulations of 18 CGCMs from phase 5 of the Coupled Model Intercomparison Project (CMIP5), together with the available Atmospheric Model Intercomparison Project (AMIP) simulations. Based on an intermodel empirical orthogonal function (EOF) analysis of tropical Pacific precipitation, the excessive equatorial Pacific cold tongue and double intertropical convergence zone (ITCZ) stand out as the most prominent errors of the current generation of CGCMs. The comparison of CMIP-AMIP pairs enables us to identify whether a given type of errors originates from atmospheric models. The equatorial Pacific cold tongue bias is associated with deficient precipitation and surface easterly wind biases in the western half of the basin in CGCMs, but these errors are absent in atmosphere-only models, indicating that the errors arise from the interaction with the ocean via Bjerknes feedback. For the double ITCZ problem, excessive precipitation south of the equator correlates well with excessive downward solar radiation in the Southern Hemisphere (SH) midlatitudes, an error traced back to atmospheric model simulations of cloud during austral spring and summer. This extratropical forcing of the ITCZ displacements is mediated by tropical ocean-atmosphere interaction and is consistent with recent studies of ocean-atmospheric energy transport balance. © 2014 American Meteorological Society.

Gu M.,Aquaculture Protein Center | Gu M.,Ocean University of China | Kortner T.M.,Aquaculture Protein Center | Penn M.,Aquaculture Protein Center | And 2 more authors.
British Journal of Nutrition | Year: 2014

Altered lipid metabolism has been shown in fish fed plant protein sources. The present study aimed to gain further insights into how intestinal and hepatic lipid absorption and metabolism are modulated by plant meal (PM) and soya-saponin (SA) inclusion in salmon feed. Post-smolt Atlantic salmon were fed for 10 weeks one of four diets based on fishmeal or PM, with or without 10Â g/kg SA. PM inclusion resulted in decreased growth performance, excessive lipid droplet accumulation in the pyloric caeca and liver, and reduced plasma cholesterol levels. Intestinal and hepatic gene expression profiling revealed an up-regulation of the expression of genes involved in lipid absorption and lipoprotein (LP) synthesis (apo, fatty acid transporters, microsomal TAG transfer protein, acyl-CoA cholesterol acyltransferase, choline kinase and choline-phosphate cytidylyltransferase A), cholesterol synthesis (3-hydroxy-3-methylglutaryl-CoA reductase) and associated transcription factors (sterol regulatory element-binding protein 2 and PPARγ). SA inclusion resulted in reduced body pools of cholesterol and bile salts. The hepatic gene expression of the rate-limiting enzyme in bile acid biosynthesis (cytochrome P450 7A1 (cyp7a1)) as well as the transcription factor liver X receptor and the bile acid transporter abcb11 (ATP-binding cassette B11) was down-regulated by SA inclusion. A significant interaction was observed between PM inclusion and SA inclusion for plasma cholesterol levels. In conclusion, gene expression profiling suggested that the capacity for LP assembly and cholesterol synthesis was up-regulated by PM exposure, probably as a compensatory mechanism for excessive lipid droplet accumulation and reduced plasma cholesterol levels. SA inclusion had hypocholesterolaemic effects on Atlantic salmon, accompanied by decreased bile salt metabolism. © 2013 The Authors .

Shang J.R.,Ocean University of China
Applied Mechanics and Materials | Year: 2014

The article mainly proposed and introduced a new model in port dust control - Dry Cleaning Mode. In Lanshan Port, for example, based on Dry Cleaning Mode connotation, the basic structure of the model were described from the technical and managerial aspects, and its operation mechanism was explained. Practice has proved that the application effect of Dry Cleaning Mode is very significant in port dust control. © (2014) Trans Tech Publications, Switzerland.

Fu X.,Ocean University of China
Journal of Computational Information Systems | Year: 2015

Aiming at the characteristic of tridiagonal linear system, this paper designs a dual-level parallel algorithm which is Based on PDD (Parallel Diagonal Dominant) and parallel partition algorithms. The dual-level parallel algorithm can make merits of both. In order to take full advantage of the dual-level parallel algorithm, this paper use hybrid MPI/OpenMP parallel paradigm to implement the dual-level parallel algorithm. Two examples are used to test the performance of the dual-level parallel algorithm. The result reveals that the speedup of the dual-level parallel algorithm is higher than PDD and increases as the order of the coefficient of tridiagonal linear system increases, which shows better scalability. © 2015 by Binary Information Press.

Wang X.,Japan National Institute of Materials Science | Cao X.,CAS Beijing National Laboratory for Molecular | Bourgeois L.,Monash University | Guan H.,Ocean University of China | And 8 more authors.
Advanced Functional Materials | Year: 2012

A new facile route to fabricate N-doped graphene-SnO 2 sandwich papers is developed. The 7,7,8,8-tetracyanoquinodimethane anion (TCNQ -) plays a key role for the formation of such structures as it acts as both the nitrogen source and complexing agent. If used in lithium-ion batteries (LIBs), the material exhibits a large capacity, high rate capability, and excellent cycling stability. The superior electrochemical performance of this novel material is the result from its unique features: excellent electronic conductivity related to the sandwich structure, short transportation length for both lithium ions and electrons, and elastomeric space to accommodate volume changes upon Li insertion/extraction. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Stossel A.,Texas A&M University | Zhang Z.,Texas A&M University | Zhang Z.,Ocean University of China | Vihma T.,Finnish Meteorological Institute
Journal of Geophysical Research: Oceans | Year: 2011

Southern Ocean (SO) sea ice simulations are particularly sensitive to wind forcing. Two real-time wind data sets covering the same period are employed to force SO sea ice in a sea ice-ocean general circulation model. Both data sets are analysis products, featuring the same temporal resolution but differing in their horizontal resolution and their source. Even in simulations where the upper ocean temperature is constrained by satellite-derived sea ice concentration, the sea ice simulations and associated surface buoyancy fluxes reveal pronounced differences along the Antarctic coastline. While the discrepancies cannot unambiguously be related to the different resolution of the wind forcing, their concentration along the coastline is indicative of being related to the representation of orography, such as coastal steep slopes and mountain ranges, including their ruggedness. Along the coast of the Weddell Sea, the net ice production rate increases by about a factor of 3 with the higher-resolution winds. On the other hand, along east Antarctica, the lower-resolution winds result in higher ice production, due to a generally stronger (overestimated) offshore component, presumably related to the smoother orography extending seaward beyond the coastline. This regionally opposite behavior leads to a relatively weak difference in total dense water formation around Antarctica and thus global deep ocean properties and circulation. Overall, the results indicate that long-term climate model projections are likely to be highly sensitive to model resolution in the Antarctic coastal zone. Copyright 2011 by the American Geophysical Union.

Schneider D.P.,Climate and Global Dynamics Laboratory | Deser C.,Climate and Global Dynamics Laboratory | Fan T.,Climate and Global Dynamics Laboratory | Fan T.,Ocean University of China
Journal of Climate | Year: 2015

Westerly wind trends at 850 hPa over the Southern Ocean during 1979-2011 exhibit strong regional and seasonal asymmetries. On an annual basis, trends in the Pacific sector (40°-60°S, 70°-160°W) are 3 times larger than zonal-mean trends related to the increase in the southern annular mode (SAM). Seasonally, the SAM-related trend is largest in austral summer, and many studies have linked this trend with stratospheric ozone depletion. In contrast, the Pacific sector trends are largest in austral autumn. It is proposed that these asymmetries can be explained by a combination of tropical teleconnections and polar ozone depletion. Six ensembles of transient atmospheric model experiments, each forced with different combinations of time-dependent radiative forcings and SSTs, support this idea. In summer, the model simulates a positive SAM-like pattern, to which ozone depletion and tropical SSTs (which contain signatures of internal variability and warming from greenhouse gasses) contribute. In autumn, the ensemble-mean response consists of stronger westerlies over the Pacific sector, explained by a Rossby wave originating from the central equatorial Pacific. While these responses resemble observations, attribution is complicated by intrinsic atmospheric variability. In the experiments forced only with tropical SSTs, individual ensemble members exhibit wind trend patterns that mimic the forced response to ozone. When the analysis presented herein is applied to 1960-2000, the primary period of ozone loss, ozone depletion largely explains the model's SAM-like zonal wind trend. The time-varying importance of these different drivers has implications for relating the historical experiments of free-running, coupled models to observations. © 2015 American Meteorological Society.

Li G.,CAS South China Sea Institute of Oceanology | Li G.,Nanjing University of Information Science and Technology | Xie S.-P.,University of California at San Diego | Xie S.-P.,Ocean University of China | Du Y.,CAS South China Sea Institute of Oceanology
Journal of Climate | Year: 2015

An open-ocean thermocline dome south of the equator is a striking feature of the Indian Ocean (IO) as a result of equatorial westerly winds. Over the thermocline dome, the El Niño-forced Rossby waves help sustain the IO basin (IOB) mode and offer climate predictability for the IO and surrounding countries. This study shows that a common equatorial easterly wind bias, by forcing a westward-propagating downwelling Rossby wave in the southern IO, induces too deep a thermocline dome over the southwestern IO (SWIO) in state-of-the-art climate models. Such a deep SWIO thermocline weakens the influence of subsurface variability on sea surface temperature (SST), reducing the IOB amplitude and possibly limiting the models' skill of regional climate prediction. To the extent that the equatorial easterly wind bias originates from errors of the South Asian summer monsoon, improving the monsoon simulation can lead to substantial improvements in simulating and predicting interannual variability in the IO. © 2015 American Meteorological Society.

Chen X.,Ocean University of China | Wallace J.M.,University of Washington
Journal of Climate | Year: 2015

ENSO-like variability is examined using a set of univariate indices based on unfiltered monthly global sea surface temperature (SST), sea level pressure (SLP), outgoing longwave radiation (OLR), sea level, and the three-dimensional ocean temperature (OT) fields. These indices, many of which correspond to the leading principal components (PCs) of the respective global fields, are highly correlated with each other. In combination with their spatial regression patterns, they provide a comprehensive description of ENSO-like variability in the atmosphere and ocean across time scales ranging from months to decades, from 1950 onward. The SLP and SST indices are highly correlated with one another back to the late nineteenth century. The interdecadal-scale shifts in the prevailing polarity of ENSO that occurred in the 1940s, the 1970s, and around the year 2000 are clearly evident in low-pass-filtered time series of these indices. On the basis of empirical mode decomposition, ENSO-like variability is partitioned into an interannual "ENSO cycle," to which equatorial ocean wave dynamics imparts a distinctive equatorial signature, and a red noise background continuum, most prominent on the interdecadal time scale, which resembles the ENSO-like variability in some models in which the atmosphere is coupled to a slab ocean. The background continuum bears the imprint of the Pacific-North American (PNA) pattern, the leading mode of the Northern Hemisphere wintertime variability of the atmospheric circulation over the Pacific sector. The superposition of the ENSO cycle and the background continuum imparts a distinctive frequency dependence to the patterns of ENSO-like climate variability. © 2015 American Meteorological Society.

Sun S.,State Oceanic Administration | Lan J.,Ocean University of China | Yue Fang T.,State Oceanic Administration | Gao X.,State Oceanic Administration
Journal of Climate | Year: 2015

Although the IndianOcean dipole (IOD) andENSOare significantly correlated, there are indeed some IODs independent of ENSO. In this research, the characteristics of independent IOD are investigated and a new triggeringmechanismis proposed based on case study and statistical analysis. Results showthat the independent IODs peak in an earlier season and have a weaker intensity compared with the IODs associated with ENSO. The wind anomaly associated with the independent IOD is very unique and shows a monsoonlike pattern, in addition to the equatorial easterly wind anomaly (EEWA) common to all IODs. The evolution of the EEWA associated with the independent IOD is well captured by the second EOF mode of the equatorial zonal wind interannual variability, suggesting that the independent IOD is an important climate mode inherent to the tropical Indian Ocean. The EEWA associated with the independent IOD is tightly linked to Indian summer monsoon activities in spring, and the convection anomalies associated with early summer monsoon onset in the Bay of Bengal plays a key role in inducing the EEWA. The EEWA can persist through spring and summer and causes a series of processes similar to those related to the IODs associated with ENSO. The correlation between the independent IOD and Indian summer monsoon activities increases dramatically after the 1980s, which is probably due to the mean state change in the tropical Indian Ocean climate system. © 2015 American Meteorological Society.

Chu J.-S.,Ocean University of China
Chinese Journal of Applied Ecology | Year: 2011

Large marine ecosystem (LME) is a large area of ocean characterized by distinct ocean-ology and ecology. Its natural characteristics require management based on ecosystem approach. A series of international treaties and regulations definitely or indirectly support that it should adopt ecosystem approach to manage LME to achieve the sustainable utilization of marine resources. In practices, some countries such as Canada, Australia, and USA have adopted ecosystem-based approach to manage their oceans, and some international organizations such as global environment fund committee have carried out a number of LME programs based on ecosystem approach. Aiming at the sustainable development of their fisheries, the regional organizations such as Caribbean Community have established regional fisheries mechanism. However, the adoption of ecosystem approach to manage LME is not only a scientific and legal issue, but also a political matter largely depending on the political will and the mutual cooperation degree of related countries.

Wang C.,National Oceanic and Atmospheric Administration | Zhang L.,National Oceanic and Atmospheric Administration | Zhang L.,University of Miami | Lee S.-K.,National Oceanic and Atmospheric Administration | And 3 more authors.
Nature Climate Change | Year: 2014

The Intergovernmental Panel on Climate Change's Fifth Assessment Report largely depends on simulations, predictions and projections by climate models. Most models, however, have deficiencies and biases that raise large uncertainties in their products. Over the past several decades, a tremendous effort has been made to improve model performance in the simulation of special regions and aspects of the climate system. Here we show that biases or errors in special regions can be linked with others at far away locations. We find in 22 climate models that regional sea surface temperature (SST) biases are commonly linked with the Atlantic meridional overturning circulation (AMOC), which is characterized by the northward flow in the upper ocean and returning southward flow in the deep ocean. A simulated weak AMOC is associated with cold biases in the entire Northern Hemisphere with an atmospheric pattern that resembles the Northern Hemisphere annular mode. The AMOC weakening is also associated with a strengthening of Antarctic Bottom Water formation and warm SST biases in the Southern Ocean. It is also shown that cold biases in the tropical North Atlantic and West African/Indian monsoon regions during the warm season in the Northern Hemisphere have interhemispheric links with warm SST biases in the tropical southeastern Pacific and Atlantic, respectively. The results suggest that improving the simulation of regional processes may not suffice for overall better model performance, as the effects of remote biases may override them. © 2014 Macmillan Publishers Limited.

Dong C.,Qingdao Agricultural University | Wei Z.,Qingdao Agricultural University | Yang G.,Ocean University of China
Fish and Shellfish Immunology | Year: 2011

Cell adhesion factors are important immune components for invertebrate to immobilize, phagocytose or encapsulate invasive microorganisms and foreign particles. In this study, a new cell adhesion factor, peroxinectin (refered as Pcpxin) was isolated from hemocytes of red swamp crayfish (Procambarus clarkii). The full-length cDNA of Pcpxin was 3014 bp encoding a protein of 819 amino acid residues with a predicted molecular weight of 89.0 kDa and a calculational isoelectric point of 6.93. The putative amino acid sequence contained a peroxidase domain and a signal peptide of 21 amino acid residues, and exhibited high identity to peroxinectin from Pacifastacus leniusculus (85%), Fenneropenaeus chinensis (62%) and Scylla serrata (58%), as well as peroxidase from Camponotus floridanus (40%), Pediculus humanus corporis (39%), and Culex quinquefasciatus (38%). Quantitative real time PCR revealed that mRNA expression of Pcpxin in hemocytes could be inhibited by challenge with heat-killed Aeromonas hydrophila, suggesting that Pcpxin was involved in immune responses to A. hydrophila. RNA interference (RNAi) experiment demonstrated that silencing Pcpxin significantly reduced the survival rate of red swamp crayfishes after challenge with A. hydrophila, which indicated that Pcpxin was important for P. clarkii to survive A. hydrophila infection. Moreover, silencing Pcpxin inhibited the up-regulation of crustin1 and lysozyme expression in response to challenge with heat-killed A. hydrophila. This result suggested that Pcpxin might participate in antibacterial peptide gene expression and thereby might be involved in signal transduction pathway regulating the expression of antibacterial peptide gene. © 2011 Elsevier Ltd.

Yu G.,Ocean University of China | Zhang J.-Y.,China Meteorological Administration
Energy Procedia | Year: 2011

Reclamation is the important utilization manner of ocean for mankind. Yet because reclamation changes natural bank shape in short term and small scale, so it can strongly disturb the whole natural system and bring a new misbalance, which affect the stability, diversity and sustainability of the seashore. In order to avoid and lighten the influence of reclamation, we should analyze and diagnose the possible effects, which can do some theory preparations for settling this problem. As a case study in Jiaozhou Bay, this paper selects 9 indicators to base the indicator system. The frame principle of the indicator system includes scientific, synthetical, viable, representative, hierarchical, systematic and data available. Basing the influencing aspects, this article uses the method of analytic hierarchy process (AHP), qualitative and quantitive method to calculate the indicators. By using the judging matrix, hierarchy sorting and indicators, the paper calculates the effect degree of reclamation to environment and ecosystem is comparatively high, and its growth is an increasing process in Jiaozhou Bay. From this point, with the reclamation scale is increasing, the effect degree of reclamation to environment and ecosystem is more and more serious. © 2011 Published by Elsevier Ltd.

Fang J.,Ocean University of China
Fuzzy Sets and Systems | Year: 2013

By making use of the intrinsic lattice-valued inclusion orders of L-subsets and that of stratified L-filters, a concept of stratified L-ordered quasiuniform limit structure is proposed, which is asymmetric and available to establish a framework of asymmetric structures. Then the category of stratified L-ordered quasiuniform limit spaces is introduced and its categorical properties are shown. The next objective of the paper is to propose a concept of stratified L-ordered principle quasiuniform limit space, and we prove that the category of stratified L-quasiuniform spaces can be embedded into the category of stratified L-quasiuniform limit spaces as a bireflective subcategory. Moreover, two ways of inducing stratified L-ordered limit structures from stratified L-ordered quasiuniform structures are presented, and the method of obtaining stratified [0,1]-ordered quasiuniform structures from [0,1]-ordered probabilistic quasiuniform limit structures and fuzzy quasi-metrics is introduced in the paper. © 2013 Elsevier B.V.

Yue Y.,Ocean University of China
Iranian Journal of Fuzzy Systems | Year: 2013

This note studies the relationship between Hutton's quasi-uniformities and Shi's quasi-uniformities. It is shown that when L satisfies"multiple choice principle" for co-prime elements, the category of Hutton's quasi-uniform spaces is a bireflective full subcategory of the category of Shi's quasi-uniform spaces. Especially, if the remote-neighborhood mapping defined by Shi preserves arbitrary joins, then the two categories are isomorphic to each other.

Zhao X.,Zhejiang University | Zhao X.,Ocean University of China | Zhao X.,Kyushu University | Hu C.,Kyushu University
Applied Ocean Research | Year: 2012

This paper presents further developments of a constrained interpolation profile (CIP)-based Cartesian grid method [29] to model nonlinear interactions between extreme waves and a floating body, which is validated against to a newly performed experiment. In the experiment, three kinds of waves (regular wave, focused wave and combined regular and focused wave) are generated and a box-shaped floating body with a superstructure is used. Validation computations on the experiment are performed by the improved CIP-based Cartesian grid method, in which the THINC/WLIC scheme (THINC: tangent of hyperbola for interface capturing; WLIC: weighed line interface calculation), is used for interface capturing. The highly nonlinear wave-body interactions, including large amplitude body motions and water-on-deck are numerically investigated through implementation of focused wave input to the CIP-based method. Computations are compared with experimental results and good agreement is achieved. The effects of the water-on-deck phenomena and different input focus positions on the body response are also dealt with in the research. © 2012 Elsevier Ltd.

Wang C.,Ocean University of China | Pawlowicz R.,University of British Columbia
Journal of Geophysical Research: Oceans | Year: 2012

Although nonlinear interactions that occur when two large internal waves collide at oblique angles are often observed in the natural world, quantitative and theoretical aspects of these interactions are only poorly understood. The available analyses are generally theoretical or the result of limited numerical experimentation, with few (if any) quantitative field measurements. Here we describe four cases of internal wave interactions, two of which involve the fundamentally non-steady generation of "Mach stems" at the site of the interaction, observed in the Strait of Georgia, Canada. Details of the interactions are quantified using time sequences of photogrammetrically rectified oblique images obtained from a circling aircraft, while simultaneous observations are made of water column properties from a surface vessel. The imaging technique allows us to estimate the speed and direction of each wave, as well as details of phase shifts induced by interactions. An existing small-amplitude theory is applied but is found to overestimate the likelihood of Mach interactions at large amplitude. © 2012. American Geophysical Union. All Rights Reserved.

Hao L.,State Oceanic Administration | Hao L.,Ocean University of China | Chen L.,Qingdao Municipal Hospital | Chen L.,Shandong University
Ecotoxicology and Environmental Safety | Year: 2012