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    25 November 2013, Volume 2013 Issue 6 Previous Issue    Next Issue
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    Article
    Krull--Schmidt decomposition of the tensor  products of certain simpleUq(gln)-modules at a root of unity
    GU Hai-xia, WANG Jian-pan
    2013, 2013 (6):  1-13. 
    Abstract ( 1489 )   PDF (183KB) ( 1926 )   Save
    Assume $\mathscr{F}$ to be a field of characteristic zero,
    and $q\in \mathscr{F}$ to be a root of unity. With $\mathscr F$ as
    the ground field and $q$ as the quantum parameter, let
    $\mathsf{s}_q(n)$ be the restricted quantum symmetric algebra of
    rank $n$, and $\Wedge_q(n)$ be the quantum exterior algebra of rank
    $n$. By [6], the homogenous components of both $\mathsf{s}_q(n)$ and
    $\Wedge_q(n)$ are simple $U_q(\mathfrak{gl}_n)$-modules. In this
    paper, we decompose the tensor product of any homogenous component
    of $\mathsf{s}_q(n)$ with any homogenous component of $\Wedge_q(n)$
    into direct sum of indecomposable modules.
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    Transaction price analysis and high-frequency trading
    LIU Chang, ZHENG Wei-an
    2013, 2013 (6):  14-21. 
    Abstract ( 3823 )   PDF (598KB) ( 2435 )   Save
    In recent years, the rapid development of high-frequency
    trading in the global financial market have gained widely attention.
    “Holding period for the assets is short but frequent” and “tiny
    yields in every trade” cause the trading sensitive to the
    transaction cost, in which the transaction price is the core. In
    this paper, a new transaction price model is constructed with the
    position information. Applied to the MACD indicator strategy, it has
    a good performance and bring a better return.
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    Ruin probabilities of a bidimensional risk model with constant interest rate
    ZHANG Yuan-yuan, WANG Wen-sheng
    2013, 2013 (6):  22-31. 
    Abstract ( 1336 )   PDF (208KB) ( 1800 )   Save
    We studied two types of ruin in the bidimensional
    framework. For each type of ruin, we derived an integro-differential
    equation for the survival probability, and an explicit asymptotic
    expression for the finite-time ruin probability when claim sizes
    have heavy tailed distributions.
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    Valuing power options under a regime-switching model
    SU Xiao-nan, WANG Wei, WANG Wen-sheng
    2013, 2013 (6):  32-39. 
    Abstract ( 1735 )   PDF (358KB) ( 2054 )   Save
    The pricing of European style power call options was
    considered when the dynamics of the underlying risky asset are
    driven by the Markov-modulated Geometric Brownian Motion. In
    particular, the market interest rate, the appreciation rate and the
    volatility of the underlying risky asset switched over time
    according to the sates of the continuous time Markov chain process.
    Since the market is incomplete, the regime switching Esscher
    transform was employed to determine an equivalent martingale measure
    and derive the valuation of the options. Then, the numerical
    analysis of our result was given.
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    Pricing model of American collar option
    CEN Yuan-jun
    2013, 2013 (6):  40-45, 56. 
    Abstract ( 1541 )   PDF (459KB) ( 1625 )   Save
    Collar option is designed for invertors with a downside
    income, and for issuers with a limit loss. The mathematical pricing
    model of the American collar option can be formulated as a
    one-dimensional parabolic variational inequality, or equivalently, a
    free boundary problem. To solve this problem, the penalty method and
    PDE arguments are applied. The existence and uniqueness of the
    solution, the properties of the free boundaries, such as
    monotonicity, smoothness, and location, are presented.
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    Boundary value apaproach to solve a class of singularly perturbed problems with spike-type contrast structure
    SONG Ci
    2013, 2013 (6):  46-56. 
    Abstract ( 1322 )   PDF (475KB) ( 1673 )   Save
    For the internal layer problem, firstly, the original
    problem was partitioned into left and right problems from the
    transfer point at the internal layer region. Then, through the
    boundary value method, the left and right problems were converted
    into non-singularly perturbed problems. And by boundary layer
    correction technique, the original problem was directly converted
    into two non-singularly perturbed problems. Lastly, the efficiency
    of the boundary value method could be indicated by numerical tests.
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    Generalized Petersen graphs admit proper total colorings with four distinguishing constraints
    YANG Chao, YAO Bing, WANG Hong-yu
    2013, 2013 (6):  57-67. 
    Abstract ( 1445 )   PDF (330KB) ( 2116 )   Save
    The study of distinguishing coloring in graphs is derived
    from the frequency assignment problem in mobile communications. This
    paper introduced the concept of $4$-adjacent vertex distinguishing
    total coloring ($4$-avdtc) of a simple graph $G$. The minimum number
    of $k$ colors required for $G$ such that it satisfies a $4$-avdtc is
    denoted as $\chi^{\prime\prime}_{4as}(G)$. For generalized Petersen
    graphs $P(n,k)$, it was proved that $6\leq
    \chi^{\prime\prime}_{4as}(P(n,k))\leq 7$.
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    Maximal Serfling inequalities for the partial sums of random variables sequence and its application
    LI Hui-bao, HU Xue-ping
    2013, 2013 (6):  68-73. 
    Abstract ( 1599 )   PDF (234KB) ( 1855 )   Save
    Using the Serfling inequality, some moment inequalities
    for the partial sums of a class of random variables sequence are
    obtained, then we mainly discuss the large deviation and the strong
    convergence by applying these moment inequalities. Some  results in
    relative literature are extended and sharpened.
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    A McCoy condition on noncommutative rings
    WANG Wen-kang
    2013, 2013 (6):  74-82. 
    Abstract ( 1217 )   PDF (231KB) ( 1612 )   Save
    Some right (resp., left) McCoy  subrings of matrix ring
    and upper triangular matrix ring over a right (resp., left) McCoy
    ring are presented. At the same time, we also give that  a right
    McCoy ring is not left McCoy and  a left   McCoy ring is not right
    McCoy. Consequently, reversible  rings satisfy a McCoy condition.
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    Improved algorithm of wavelet thresholding for image denoising
    GAO Wen-zhong, CHEN Zhi-yun, ZENG Qiu-mei
    2013, 2013 (6):  83-92. 
    Abstract ( 1718 )   PDF (3166KB) ( 2293 )   Save
    The algorithm of the image denoising based on wavelet thresholding shrinkage has been studied. On this basis of soft thresholding function, an improved thresholding function was proposed. The improved thresholding function uses BayesShrink thresholding and SureShrink thresholding to suppress the too many reservations of wavelet coefficients which are produced by SureShrink thresholding. Compared with traditional algorithm (the soft threshold function method (BayesShrink thresholding), the soft threshold function method (SureShrink thresholding), the hard threshold function method and the semi-soft threshold function method), in dealing with the image with few edge points, the processed image based on the improved algorithm has a higher Peak Signal to Noise Ratio(PSNR), a higher Signal to Noise Ratio(SNR), and a lower Mean Square Error(MSE). The processed image based on the improved algorithm is clearer.
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    Improved LDA model for microblog topic mining
    XIE Hao, JIANG Hong
    2013, 2013 (6):  93-101. 
    Abstract ( 3508 )   PDF (1181KB) ( 3136 )   Save
    With the dramatic increase of Sina microblog users, microblog websites have been the platformsfor a wide spectrum of users to get information. Due to the fact that microblog is a special kind of text with the restricted length, traditional topic models could not be used to analyze the microblog content very well. RT-LDA, a microblog generation model based on LDA is proposed in this paper. Gibbs sampling is chosen to deduce the model, which can not only mine the topics of each microblog accurately but also induce the distribution of the concerned topics. RT-LDA’s effective utility on topic mining of the microblogs is verified by the experiments on real data.
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    Weak signal DOA estimation method based on synthetic spectrum without prior knowledge of source number
    HOU Shuai PAN Wei
    2013, 2013 (6):  102-111. 
    Abstract ( 1462 )   PDF (3029KB) ( 2015 )   Save
    For the problem of the source number and DOA estimation of the weak signals in the interference of the strong signals, a novel method based on synthetic spectrum is proposed. In this method, the outputs of the eigen-beam channels are superimposed by different weights to form a spatial spectrum function. Then the function is used to weight the spatial spectrum function derived from the noise subspace approximation method. Finally, the synthetic spectrum function is constructed to estimate the DOAs of the weak signals without the prior knowledge of source number. Compared to the prevois method based on eigen beamforming, the proposed method has better performance when the DOAs of weak signals are close to each other. The effectiveness and advantage of this method is verified by the simulation results.
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    Mg(Zn, Mn)-doped Cobalt ferrites: a first-principles study
    XIAO Tian-liang, DING Hang-Chen, GONG Shi-Jing, DUAN Chun-gang
    2013, 2013 (6):  112-119. 
    Abstract ( 1581 )   PDF (1613KB) ( 2274 )   Save
    Using generalized gradient approximation plus U method, we present electronic and magnetic properties through a systemic theoretical calculation of YxCo1-xFe2O4(Y=Mg, Zn, Mn,x=0.00, 0.25, 0.50, 0.75, 1.00). Our main results show that: ①  the octahedral Co2+B ions may show high/low spin states under different doping concentration x; ② magnetic moments of high spin state for Co2+B can be changed by different doping degrees, it ranges from 2.54 μB to 2.85 μB; ③  the spinel structure will change from metal to half-metal at the inversion degree region from 0.75 to 1.00.
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    Influence of electrical conductivity of multi-walled carbon nanotubes by halogen-doping
    SHI Guo-Xian XU Xue-Cheng
    2013, 2013 (6):  120-126. 
    Abstract ( 1826 )   PDF (1822KB) ( 2603 )   Save
    Multi-walled carbon nanotubes (MWNTs) were doped by chlorine, bromine and iodine. Compared with the pristine MWNTs, the electrical conductivities of Cl2-MWNT and Br2-MWNTs were improved over 5 times and 3 times, respectively, while that of I2-MWNTs almost unchanged. The interaction between the halogen and MWNTs was analyzed by Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). Meanwhile, we also studied the carrier concentration and carrier mobility which may affect the conductivities of the composite. The results show that: When the halogen electronegativity become stronger, the mean free path of the carrier of doped MWNTs will be higher, as well as the carrier mobility. And the stonger the interaction between the halogen and MWNTs become, the more carriers will take part in conducting, which means the carrier concentration will be higher.
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    Influence of pH value on the properties of the composite wires by chemical deposition
    LUAN Hong-yan, LI Xin, WANG Rui-li, PAN Hai-lin,CHEN De-lu, ZHAO Zhen-jie
    2013, 2013 (6):  127-132. 
    Abstract ( 1423 )   PDF (2736KB) ( 1893 )   Save
    Composite wires of 100 μm diameter CuBe coated with a layer of NiCoP were prepared by chemical plating, and dc current of 150 mA got through CuBe wires during the process. The influence of pH value on the composite wires was studied in terms of morphology, deposition speed, composition, magnetic property and the GMI effect. The results showed that the pH value influenced GMI effect and critical frequency by changing the roughness of materials, deposition speed, the coating composition and magnetic structure. The maximum GMI effect of 868% is obtained at the pH value of 8.4.
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    Properties of novel poly (aryl ether quinoxaline)s (PEQs)
    ZHAO Qiu-tang, Ding Ya-ming, HUA hui
    2013, 2013 (6):  134-140. 
    Abstract ( 7595 )   PDF (1409KB) ( 2025 )   Save
    Novel poly(aryl ether quinoxaline)s (PEQs) were prepared via a new two-step procedure. Firstly, poly (ether benzil) (PEB) was synthesized by the polycondensation of 4,4′-difluorobenzil and 4,4′-isopropylidenediphenol. Then, PEQs were synthesized through chemical modification of PEB by 1,2-diaminobenzene and a small amount of 4,4′-oxydibenzene-1,2-diamine(OBDA). The polymers were characterized by IR, NMR, TMA and other measurements. Experiments show that these PEQs can be dissolved in common organic solvents, such as DMF and THF; these PEQs were dissolved in THF to get films which had good transmittance in the visible region (the transmittance was up to 85% at 450 nm). In addition, they also had higher glass transition temperatures (Tg>210 ℃), good thermal and mechanical properties, as well as excellent resistance to strong acid and alkali. They are expected to be useful functional materials.
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    Poly (L-γ-glutamylglutamine) nanoparticles enhance drug accumulation in resistant cells
    LIU Kai, CHEN Jing, WANG Jing, YU Lei, ZHU Jian-zhong, WANG Yi-ting
    2013, 2013 (6):  141-149. 
    Abstract ( 1457 )   PDF (2072KB) ( 2118 )   Save
    This work investigated the antitumor efficacy of poly (L-γ-glutamylglutamine) (PGG) prodrug in multidrug resistant (MDR) cancer cells and the possible mechanisms.  The A549 cell line was induced to become multidrug resistant.  A549 was applied to evaluate the effect of PGG-Dox on intracellular accumulation and retention of Dox. Endocytosis inhibition studies and transmission electron microscope assay were used to investigate the mechanisms of cellular PGG-Dox uptake.  Confocal laser scanning microscopy was performed to confirm the drug accumulation.  Treatment of MDR cells with PGG-Dox resulted in significantly enhanced drug accumulation and retention after the end of treatment compared with free Dox.  Endocytosis inhibition studies showed pinocytosis is the mainly pathway in the elevated membrane permeability of the PGG-Dox.  These demonstrated that Dox conjugate with PGG NPs effectively bypass the multidrug resistance.  Our PGG DDS may be considered as an attractive and promising delivery system to overcome multidrug resistance.
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    Characters on the seed dormancy and germination of an endangered species, Ostrya rehderiana, in Tianmu Mountain, China
    LE Xiao-wei, CUI Min-yan, YANG Shu-zhen, LUO Yuan,ZHAO Ming-shui, LI Yuan-yuan
    2013, 2013 (6):  150-158. 
    Abstract ( 1766 )   PDF (1356KB) ( 1671 )   Save
    Ostrya rehderiana is a critically endangered plant species with only five natural individuals remaining in Tianmu Mountain, Zhejiang Province, China. To explore the seed dormancy and germination of O. rehderiana, the seeds were collected from the natural individuals in November 2008 and 2009 and manipulated in illumination incubator in different treatments. Results showed that these seeds have a water absorption rate of 20% after immerging in water for 4 h (p<0.05), indicating it was not physical dormancy (PY). The seeds have higher cumulative germination rates after short low temperature storage (4 weeks v.s. 16 weeks; p<0.05), suggesting low temperature might induce seeds dormancy of O. rehderiana. To break dormancy, relative longer times (median length of germination time=54 d) of temperature above 15 ℃ were needed, indicating the seeds may belong to physiological dormancy (PD). The most favorable germination condition was 15/25 ℃ employing 400 or 600 mg·L-1 GA. We conclude that seeds treated with GA should be sown in a fitting condition immediately to germinate well in the ex situ conservation of O. rehderiana. In addition, it is a feasible method that seeds germinate in the nature with added GA artificially.
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    Analysis of sugar metabolism and its related enzymes activities during vase-holding days of cut rose petal
    LI Long, WANG Hai-hong, CHEN Zhao-liang, QIAO Yong-jin, WANG Li
    2013, 2013 (6):  159-164. 
    Abstract ( 1504 )   PDF (1395KB) ( 2226 )   Save
    Analyze changes of sugar metabolism and its related enzymes activities during vase-holding days of cut roses named “cv. Black Magic flower” and “cv. Movie Star flower” were studied. The results showed that glucose and fructose contents increased rapidly with the cell enlargement in the petals and during flower growth, but the content of sucrose dropped gradually. The cut rose named “cv. Movie Star flower” had a larger hexoses (glucose+fructose) content , fresh weight and a bigger flower diameter fresh weight than “cv. Black Magic flower” . The activity of acid invertase (AI) was always at a higher level than those of the neutral invertase (NI), sucrose synthase (SS) and sucrose phosphate synthase (SPS). The activity of acid invertase (AI) was positively correlated with sucrose degradation index (SDI). In conclusion, the acid invertase (AI) was a key enzyme in the sucrose degradation and hexoses accumulation, while hexose accumulation in the petal might be important for flower growth and development in cut rose.
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    HPLC-ESI-MS determination of neurotransmitters L-serine/D-serine in rat brain tissues
    WANG Wei-li, DUAN Ya-le, LIU Sha, ZHANG Yao, ZHAO Zheng
    2013, 2013 (6):  165-170. 
    Abstract ( 1839 )   PDF (1032KB) ( 1786 )   Save
    A highly sensitive and selective high performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) assay was developed for the determination of neurotransmitters L-serine/D-serine in rat brain tissues. The rat brain was removed, homogenized and centrifuged.L-serine/D-serine in the supernatant was derivatized with the Marfey’s reagent. The derivatives were separated by HPLC under gradient elution of mobile phase consisting of ammonium formate and acetonitrile and detected by ESI-MS in the negative ion mode. Reverse phase chromatographic resolution of the enantiomers was obtained within 22 min. Good linear correlations of the concentration to the peak area were obtained in the ranges of 2.5~500 ng/mg for L-serine and 1.2~250 ng/mg for D-serine. The extraction recoveries for both analysts were in the range of 81% to 89%. The method was then applied to determine the levels of the neurotransmitters in cerebral cortex and hippocampus of the adult and aged rats. The results showed that L-serine levels kept unchanged,while D-serine levels decreased significantly, in cortex and hippocampus of the aged rats compared with those of the adult rats, suggesting an involvement of D-serine in the normal aging process.
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    Analysis of gal-3 gene diversity of Bufo gargarizans
    PAN Li-nian, WAN Wen-bin, ZHANG Shu-fang, ZHU-GE Hui, ZHOU Pin-pin, YANG Xian-yu
    2013, 2013 (6):  171-180. 
    Abstract ( 2176 )   PDF (5459KB) ( 2090 )   Save
    Three independent groups of first-strand cDNAs were synthesized from the total RNA extracted from the skin of a single individual of Bufo gargarizans using different kits including SMARTer TM RACE cDNA Amplification Kit and modified Quantscript RT kit, which were then used as templates for the subsequent polymerase chain reaction (PCR). The PCR products were cloned into the pGM-T vector and sequenced. As a result, 16 different uni-cDNAs were singled out of the total 31 cDNA clones. Same sequences, single nucleotide polymorphism sites (SNPs) and base deletions were detected in two or three independent experiments/groups, indicating gal-3 diversity, which led to diversity of proteins encoded. But alignment of the amino acid residues deduced form these gal-3 cDNAs revealed high conservation of glycosyl-binding sites, phosphorelation sites and the motifs highly associated with biological functions, which suggested the existence of galectin-3 diversity in the skin of B. gargarizans.
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    Development and application of the Cross-platform Intelligent e-Education Service Platform
    WU Yong-he, HE Chao, FENG Xiang, WANG Jian,SHEN Jian, REN You-qun
    2013, 2013 (6):  181-192. 
    Abstract ( 1502 )   PDF (6565KB) ( 1826 )   Save
    The Cross-platform Intelligent e-Education Service Platform (CIeESP) is a major task of scientific research assigned by the Science and Technology Committee of Shanghai Municipality, with its main goal being to build the cross-platform intelligent e-education service platform and study its business model. This paper introduced the development and application of the platform from three aspects: design idea, system design and implement. First, the CIeESP plat form based on cloud service and four subsystems, including Education Resource Management Subsystem, Learning Subsystem Based on Mobile Terminal, Education Resource Supermarket Subsystem and Online Interactive Learning Subsystem, are explained from technology resolution, system deployment and application. Second, the development of education resource based on two-dimension code is illustrated, and its demonstration and model are provided from two kind of services based on two-dimension code and of online interactive learning and business model, respectively. Then the usability test for the System is described. Finally, summary and outlook are given.
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    QR-code based design of supplementary book service platform
    FENG Xiang, WU Yong-he, WANG Jian, REN You-qun
    2013, 2013 (6):  193-201. 
    Abstract ( 1864 )   PDF (4263KB) ( 2701 )   Save
    This study applied two-dimensional code in the design of a supplementary book distribution system: used it as the entrance to the digital world, constructed a services platform, developed a mobile application for ubiquitous learning, and built a supplementary publishing ecosystem. The study connects supplementary books and digital supplementary resources seamlessly, providing better learning experience. The research result has been applied by the Press of East China Normal University in distribution of paper supplementary books and yield good results.
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