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    25 March 2016, Volume 2016 Issue 2 Previous Issue    Next Issue
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    Article
    A review of the studies on melanin synthesis and whitening products
    YE Xi-Yun, ZHU Ping-Ya
    2016, 2016 (2):  1-8.  doi: 10.3969/j.issn.1000-5641.2016.02.001
    Abstract ( 909 )   HTML ( 19 )   PDF (777KB) ( 1263 )   Save
    Due to environmental pollution and the increasing size of the ozone hole, more UV rays penetrate the atmosphere and reach the ground, which leads to skin pigmentation abnormalities. In this article, we reviewed the latest studies on melanin synthesis, mainly focusing on the regulation and related signal pathways with regard to tyrosinase, a vital rate-limiting enzyme involved in this process. Several critical factors affecting melanin synthesis were also presented, providing theoretical basis for screening melanin inhibitors. In addition, several new popular commercial whitening products and their property were discussed. All these information is benificial to draw the public’s attention to skin pigmentation disorder as well as proper care.
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     Effcient characterization for M{2,3},M{2,4} and M{2,3,4}and Mf2;3;4g 
    ZHENG Dao-Sheng
    2016, 2016 (2):  9-19.  doi: 2016.02.002
    Abstract ( 552 )   HTML ( 92 )   PDF (246KB) ( 973 )   Save
    In this paper, by {\it selecting inverse image index method}, an efficient characterization formula from set ${\mathbb{A}}_{1}=\{\alpha:\alpha=(I_s,\eta^{\rm T})^{\rm T}\in \Bbb C^{n\times s}_s\}$ onto set ${\mathbb{B}}_1=\{\beta:\beta=\alpha(\alpha^*\alpha)^{-1}\alpha^*, \alpha\in{\mathbb{A}}_1\}$ is given. Besides, it is shown that each element of $I\{2,3\}_s$ is permutation similar to an element of ${\mathbb{B}}_1$. Then efficient characterization formulas for $I\{2,3\}$ and $M\{2,3\}$ are obtained respectively. An interesting thing is ${\mathbb{B}}_1$ is a dense subset of $I\{2,3\}_s$. The fact that $I\{2,3\}_s=I\{2,4\}_s=I\{2,3,4\}_s$ enables us to obtain the efficient characterization formulas for $M\{2,4\}$ and $M\{2,3,4\}$ fluently. Algorithm 3.1 may be used to compute elements of $I\{2,3\}_s$ and to avoid the repeated computation work.
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    Support vector machine in the primal space based on\\ the ramp loss function\\[6mm
    YUAN Yu-Ping, AN Zeng-Long
    2016, 2016 (2):  20-29.  doi: 2016.02.003
    Abstract ( 598 )   HTML ( 5 )   PDF (521KB) ( 1101 )   Save
    Aiming at the problem of standard support vector machine being sensitive to the noise, a new method of support vector regression (SVR) machine based on dissymmetry quadratic and controlled-insensitive loss function is proposed. Using the concave and convex process optimization and the smooth technology algorithm, the problem of non-convex optimization is transformed into the problem of the continuous and twice differentiable convex optimization. Using the Amijo-Newton optimized algorithm of finite iteration termination, the established optimization model is solved, and the convergence of the algorithm is analyzed. The algorithm can not only keep the sparse nature of support vector, but also control the abnormal values of the training sample. The results of theexperiment showed that the support vector regression machine model proposed kept good generalization ability, and the model could fit better both the simulated data and the standard data. Compared with the standard support vector machine (SVM) model, the proposed model not only can reduce the effects of noise and outliers, but also has stronger robustness.
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    A note on the commutativity of {C}^*-algebras
    JIANG Run-Liang
    2016, 2016 (2):  30-34.  doi: 2016.02.004
    Abstract ( 608 )   HTML ( 8 )   PDF (164KB) ( 1005 )   Save
    There are many characterizations for commutative C^*-algebras. In this note, we prove that a C^*-algebra $\mathcal{A} is not commutative if and only if there is a C^*-subalgebra \mathcal{B} in \mathcal{A}'' (the enveloping Von Neumann algebra of mathcal{A}) such that mathcal{B} is-isomorphic to mathrm M_2(\mathcal{\textbf{C}}). In terms of this result, we can recover some characterizations for the commutativity of C^-algebras appeared before.
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    Existence of time-dependent global attractors for plate equations
    LIU Ting-Ting, MA Qiao-Zhen
    2016, 2016 (2):  35-44.  doi: 2016.02.005
    Abstract ( 515 )   HTML ( 8 )   PDF (300KB) ( 987 )   Save
    The concept of time-dependent global attractors was recently presented by Di Plinio, Temam et al.~By using the skill of the operator decomposition, the asymptotic compactness of a family process \{U(t,\tau)\} corresponding to the plate equations with the coefficient dependent on time was proved,~and then the existence of time-dependent global attractors as well as the regularity were obtained under the condition that f satisfies the critical exponent growth
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    Reliability coefficient of star complex system
    ZHANG Qi-Bin, SHA Xiao-Cong, WANG Na, XU Hui-Ping, MA Ji
    2016, 2016 (2):  45-50.  doi: 2016.02.006
    Abstract ( 410 )   HTML ( 8 )   PDF (300KB) ( 825 )   Save
    The reliability coefficients play an important role in the reduction of complex systems to a linear combination of parallel subsystems. This paper defines a new complex system, namely, star-k-out-of-n:F system, and calculates the reliability coefficients of this system
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    List improper coloring of graphs of nonnegative characteristic
    XU Yang
    2016, 2016 (2):  51-55.  doi: 2016.02.007
    Abstract ( 421 )   HTML ( 9 )   PDF (174KB) ( 1000 )   Save
    A graph G is called (k,d)^*-choosable if, for every list assignment L with |L(v)|=k for all v\in V(G), there is anL$-coloring of G such that every vertex has at most d neighbors receiving the same color as itself. Let G be a graph embedded in a surface of nonnegative characteristic. In this paper, we prove that if G is a 2-connected graph, which contains no 5-cycles, adjacent 3-faces and adjacent 4-faces, then G is (3,1)^*-choosable
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    Minimum fundamental cycle basis of (n-2)-regular bipartite graphs with order 2n
    HE Chang-Xiang, LIU Wei-Long
    2016, 2016 (2):  56-61.  doi: 2016.02.008
    Abstract ( 532 )   HTML ( 5 )   PDF (264KB) ( 1000 )   Save
    Let G be an (n-2)- regular bipartite graph with order 2n. In this paper, we constructed a fundamental cycle basis of G and proved this basis is a minimum fundamental cycle basis. For any minimum fundamental cycle basis, we also determined the structure of the spanning tree corresponding to it.
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    An effective localization attack in locationbased social network
    WANG Rong-Rong, XUE Min-Hui, LI Xiang-Xue, QIAN Hai-Feng
    2016, 2016 (2):  62-72.  doi: 10.3969/j.issn.1000-5641.2016.02.009
    Abstract ( 756 )   HTML ( 7 )   PDF (1642KB) ( 1331 )   Save
    Locationbased social network (LBSN) services enable users to discover nearby people. Original LBSN services provide the exact distances for nearby users. Existing studies have shown that it is easy to localize target users by using trilateration methodology. To defend against the trilateration attack, current LBSN services adopt the concentric bandbased approach when reporting distances. In this paper, by using number theory, we analytically show that by strategically placing multiple virtual probes as fake GPS, one can accurately pinpoint user locations with either accurate or coarse bandbased distances. As a proof of this concept, WeChat is examplified to validate that our attack methodology is effective in a realworld deployment. Our study is expected to draw more public attention to this serious privacy issue and hopefully motivate better privacypreserving LBSN designs.
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    A novel orientation sensing method based on\\RFID technology
    GUO Feng-Ming, LI Bing, HE Yi-Gang,
    2016, 2016 (2):  73-80.  doi: 2016.02.010
    Abstract ( 465 )   HTML ( 7 )   PDF (548KB) ( 1016 )   Save
    It is critical to sense orientation of target objects for radio frequency identification (RFID) applications, such as supply chain, equipment management, and so on. Based on the principles of ultra high frequency radio frequency identification (UHF RFID) and the theory of antenna scattering, a link budgets model of RFID is provided. Utilizing the technology of RFID and polarization diversity, a novel method for sensing the orientation is presented. The method requires standard RFID equipment and assumes that each object is attached by two RFID tags. Based on the received signal strength of the tag reply, orientation of the target object is obtained by using of a simple statistical estimator. The performance of the method proposed is evaluated via experimental measurements, and the results show that the mean estimated error of orientation sensing is 10.1^{\circ}
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    Climate change and droughtflood disasters responses in South China
    WANG Wen-Jing, YAN Jun-Ping, LIU Yong-Lin, CAO Yong-Wang
    2016, 2016 (2):  81-89.  doi: 10.3969/j.issn.1000-5641.2016.02.011
    Abstract ( 715 )   HTML ( 6 )   PDF (2978KB) ( 1292 )   Save
    According to the meteorological data of 80 stations in South China, influences of different disaster inducing factors on climate change were analyzed, using MannKendall test method, standardized precipitation index, the wavelet analysis, to explore the trend of drought and flood under global warming background. The results showed that: (1) In the last 54 years, the annual average temperature was 19.95 °C in South China, with a linear tendency being 0.17 °C/10a. The abrupt change of average annual temperature occurred in 1993. (2) The precipitation in South China was increasing with the speed of 8.775 mm/10a. After the abrupt change of temperature,the temperature increased fast, while the precipitation decreased rapidly. The colding and wetting in spring changed to warming and wetting; the warming and drying in autumn changed to warming and wetting; the warming and wetting in winter changed to warming and drying.(3) According to the amount of annual precipitation, South China area was divided into two regions: the average annual precipitation in Yunnan province was increasing along the latitude direction from north to south; the average annual precipitation in the other provinces were increasing along the longitude direction from east to west. (4) The flood increased and drought reduced after the abrupt change of temperature. The frequency of flood increased in some areas, while the frequency of drought reduced in space. Therefore, the overall climate change presented a warming and wetting trend.
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    Responses of runoffsediment flux and bedform in the Middle Yangtze River to the completion of the Three Gorges Dam
    YUAN Wen-Hao, LI Mao-Tian, CHEN Zhong-Yuan, YIN Dao-Wei, WEI Tao-Yuan
    2016, 2016 (2):  90-100.  doi: 10.3969/j.issn.1000-5641.2016.02.012
    Abstract ( 826 )   HTML ( 6 )   PDF (2996KB) ( 1179 )   Save
    Comparation methods are used to examine the responses of hydrosediment and river bedform after the completion of the Three Gorges Dam. Data are based on the historical data of runoff and sediment discharge (1950—2013) and insite measured data of depth and bedload (2003, 2011).  The results demonstrate that the average annual discharge at Yichang and Hankou stations has decreased 10.1% and 7.2% after the Three Gorges Dam completion. The average annual sediment flux of the Yichang and Hankou stations decreased from 556 and 402 Mt/a to 60 and 150 Mt/a, accounted for 89.5% and 62.2% of that have been trapped by the Three Gorges Dam. In addition, the average annual medium diameter of suspended sediment at Yichang and Hankou stations has decreased from 35 \mm and 25 \mm to 4 \mm and 15 \mm, but the bed load has become coarser and coarser. The depth at the thalweg has also increased to 0.4~3.7 m due to the bed erosion after the Three Gorges Dam impoundment.
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    Observation and analyses of transport and diffusion of warm discharge water from the power plants near Shidongkou in the Changjiang Estuary
    ZHANG Shen-Yu, ZHU Jian-Rong
    2016, 2016 (2):  101-111.  doi: 10.3969/j.issn.1000-5641.2016.02.013
    Abstract ( 624 )   HTML ( 9 )   PDF (6468KB) ( 948 )   Save
    The transport and diffusion of warm discharge water from the power plants near Shidongkou in the Changjiang Estuary were analyzed based on the observation data from November 23 to December 2 in 2014. During the spring tide, in terms of the longitudinal distribution of water temperature, warm discharge water from the power plants was evident, and had the maximum water temperature rise of 4.1oC in ebb tide, and of 5.1oC in flood tide; water temperature was stratification only near the discharge port, and trended to vertical uniform in other area due to strong mixing induced by tidal current. In terms of horizontal distribution of water temperature and water temperature rise, water temperature was higher along the coast and lower away from the coast, and reached the maximum value of 4.0oC near the discharge ports of Huaneng Shidongkou power plants during the ebb tide. The warm discharge water was transported and diffused downstream along the coast forced by the ebb current and Coriolis force. Compared during ebb tide, the higher temperature water near the Shidongkou move upstream and farer away the coast during flood tide, the maximum water temperature rise reached to 4.2oC. In terms of current speed and direction, water temperature measured at the continuous sites, water temperature rise during flood tide if the measured sites located in the upper reaches of the power plant, and descend during ebb tide if the measured sites located in the lower reaches of the power plant, was influenced distinctly by the near warm discharge water from the power plants. The more the measured site closer to discharge port of power plant, the higher the water temperature was, and the more obvious the vertical variation was. During the neap tide, water temperature was lower than during spring tide due to the passage of the cold front and heat loss at the river surface, the maximum water temperature near the power plant appeared at the middle water layer. The distribution characteristic of warm water rise was similar to the one during spring tide. The maximum warm water rise reached to 5.0oC which was higher 0.8oC than the one during spring tide because the tidal current and mixing was weaker during neap tide, and the higher temperature water near the warm water discharge port was not easy to be outward transport and diffusion.
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    Numerical simulation about temporal and spatial variations of overtopping flow flux at the south leading jetty in the deep waterway project of the Changjiang Estuary
    XU Peng, GE Jian-Zhong, DING Ping-Xing, FU Gui
    2016, 2016 (2):  112-127.  doi: 10.3969/j.issn.1000-5641.2016.02.014
    Abstract ( 624 )   HTML ( 8 )   PDF (7882KB) ( 1037 )   Save
    A numerical model based on the insitu measured topographic data was implemented, using the unstructuredgrid, threedimensional primitive equation, finitevolume coastal ocean model (FVCOM) including a dikegroyne module, for the study of temporal and spatial variations of overtopping flow at the south leading jetty constructed in the deep waterway channel. We investigated the temporal and spatial changes of overtopping flow by computing crosssection water flux before and after the project. The hydrodynamic condition around the north passage showed noticeable changes after the building of dikes and groynes. After the construction, respectively, net lateral current between the two channels points to the north passage with a relatively large amount of discharge. As estimated, spatially varying unit width net overtopping water flux had a significant feature, which was bounded at the corner, showed that the flux increased gradually at the upper half and decreased at the latter with a larger value. On a time scale the amplitude appeared no remarkable changes seasonally but on the other hand paced periodically in a tidal cycle. Moreover, the results showed a strong linear correlation between net water flux and tidal level.
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    Design and application of saltwater intrusion forecastingsystem in the Changjiang Estuary
    TAO Ying-Jia, GE Jian-Zhong, DING Ping-Xing
    2016, 2016 (2):  128-143.  doi: 10.3969/j.issn.1000-5641.2016.02.015
    Abstract ( 676 )   HTML ( 9 )   PDF (13824KB) ( 972 )   Save
    Based on a highresolution and wellvalidated FVCOM model, a saltwater intrusion forecasting system in the Changjiang Estuary has been set up.A WRF model is also applied to predict the wind speed and direction in the Changjiang Estuary and its adjacent sea. The forecasting system can forecast threedimensional spatial distribution of salinity in the Changjiang Estuary at each moment during the following three days (72 hours).The forecasting system downloads the forcing data, runs the WRF and FVCOM model, visualizes prediction results and publishes the results. All the above operations are automatically processed by computer.The system was validated by hindcasting salinity of two stations, which are Baozhen and Chongxi at South Branch, during January 2011. The comparison of salinity between system hindcasted value and observation show the system is reliable. The system, with advantages of convenient operation and automatic procession, forecasts the saltwater intrusion in the Changjiang Estuary easily and timely.
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    Ultrasensitive detection of protein biomarker using fluorescent quantum dot probes
    WU Si-Min, JIA Chun-Ping, LIU Li-Fen, GAO Wan-Lei, JING Feng-Xiang, Jin-Qing-Hui , ZHANG Hong-Feng, ZHAO Jian-Long-
    2016, 2016 (2):  144-152.  doi: 10.3969/j.issn.1000-5641.2016.02.016
    Abstract ( 743 )   HTML ( 7 )   PDF (2643KB) ( 655 )   Save
    In this study, based on the unique properties of quantum dots (QDs) and immune magnetic beads, an fluorescent assay was built to detect low concentration carcinoembryonic antigen (CEA). The assay was carried out in a sandwich formation in which two antibodies simultaneously recognized two separate binding sites on the same target CEA. After enrichment with magnetic separator, the fluorescent intensities produced by the QDs, which were confined to the surface of the beads, could be read efficiently to quantify the concentration of the CEA. For this assay, the limit of detection was 38 pg/mL with the linear range was from 0.39 to 50 ng/mL, and it has been proved with high accuracy and repeatability in tumor marker control. With the high sensitivity, specificity and low sample consumption, this method takes a big step to the early diagnosis of diseases.
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    New records for alien  plants in Shanghai
    LI Hui-Ru, WANG Yuan, MA Jin-Shuang
    2016, 2016 (2):  153-159.  doi: 10.3969/j.issn.1000-5641.2016.02.017
    Abstract ( 660 )   HTML ( 99 )   PDF (3115KB) ( 1095 )   Save
    Ten new alien species belonged to ten genera and nine families, are recorded in Shanghai, including Rumex maritimus L., Chenopodium acuminatum Willd., Aubrieta deltoidea (L.) DC., Trifolium resupinatum L., Malva pusilla Sm., Anagallis arvensis L., Verbena bonariensis L., Leonurus macranthus Maxim., Stachys arvensis L.and Panicum miliaceum L.. Among them, A.deltoidea (L.)DC. and T.resupinatum L. are new record for alien plants in China.
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    Effect of redox condition on metal transformation in urban river sediments
    ZHANG Mi, WEN Bo, HUANG Ling-Xia, DU Jing, DENG Hong-
    2016, 2016 (2):  160.  doi: 10.3969/j.issn.10005641.2016.02.018
    Abstract ( 727 )   HTML ( 12 )   PDF (2640KB) ( 1108 )   Save
    The sediments from Yinchu Lake and Liwa River were studied for the effects of redox changes on Zn and Fe transformation. A simulated experiment was conducted with 4 different redox treatments:aerobic (+O), anaerobic (-O), aerobic then anaerobic (+O→-O) and extensively anaerobic (--O). Compared with anaerobic condition (-O), percentage of oxidizable Fe decreased from 5.53% to 4.60% in the sediment from Yinchu Lake under aerobic condition, while reducible and residual Fe increased from 13.77% to 16.20% and from 81.08% to 83.49%, respectively. Furthermore, the concentration of Fe release in the supernatant was decreased. Percentage of Zn in acid extractable, reducible and FeMn oxides fraction were respectively declined from 30.14% to 29.16%, from 25.40% to 23.90% and from 35.73% to 32.72% in the sediment from Yinchu Lake. However, Zn in residual fraction rose from 32.73% to 35.92% after treated with oxygenenation, which decreased the concentration of Zn release in the supernatant. It indicated that Fe and Zn in FeMn oxides fraction and organic matter fraction had good corrections with each other. Our study would provide scientific basis for risk analysis and evalution on eutrophicated urban river in the process of ecological restoration.
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