Phylogenetic position of sponges in early metazoan evolution and bionic applications of siliceous sponge spicules

Sponges are the oldest and the simplest but not primitive multicellular animals. They represent the earliest evolutionary metazoan phylum still extant. It was a long and painful scientific process to posi-tion the most enigmatic and mysterious metazoan,the Porifera,into their correct phylogenetic place among the eukaryotes in general and multicellular animals in particular. As living fossils,sponges provide the best evidence for the early evolution of Metazoa. More recently,interest has been focused on the bionic applications of sponges' siliceous spicules,after the discovery of their unique structure and high fiber performance. In this review,the emergence of sponges,evolutionary novelties found in sponges,and the phylogenetic position of sponges in early metazoan evolution are highlighted. In ad-dition,the present state of knowledge on silicatein-mediated "biosilica" formation in marine sponges,including the involvement of other molecules in silica metabolism and their potential application in nanobiotechnology and medicine,is given.     

Control of group velocity in an annular chain of microring coupled-resonator optical waveguides

In order to control group velocity,an annular chain of microring coupled-resonator optical waveguides was analyzed,and its transmission spectra were obtained using the transfer matrix method. The result showed that the curvature of the chain caused the dispersion curves to shift and the resonance fre-quency got fixed. It is therefore concluded that the group velocity of light in the annular chain of mi-croring coupled-resonator optical waveguides can be controlled by adjusting the curvature of the chain. We believe that such an annular chain can be used as an optical buffer or signal retarder for optical communication.     

A Large Deviation Principle for the Risk Process with Varying Premium

Let u ∈ R ,for any ω 〉 0, the processes X^ε = {X^ε（t）; 0 ≤ t≤ 1} are governed by the following random evolution equations dX^ε（t）= b（X^ε（t）,v（t））dt-εdSt/ε, where S={St; 0≤t≤1} is a compound Poisson process, the process v={v（t）; 0≤t≤1} is independent of S and takes values in R^m. We derive the large deviation principle for{（X^ε,v（.））; ε〉0} when ε↓0 by approximation method and contraction principle, which will be meaningful for us to find out the path property for the risk process of this type.     

Wavelet Numerical Solutions for Weakly Singular Fredholm Integral Equations of the Second Kind

Daubechies interval wavelet is used to solve numerically weakly singular Fredholm integral equations of the second kind. Utilizing the orthogonality of the wavelet basis,the integral equation is reduced into a linear system of equations. The vanishing moments of the wavelet make the wavelet coefficient matrices sparse,while the continuity of the derivative functions of basis overcomes naturally the singular problem of the integral solution. The uniform convergence of the approximate solution by the wavelet method is proved and the error bound is given. Finally,numerical example is presented to show the application of the wavelet method.     

Research on the Bit Computation Model for Time Variable Channel Bandwidth

For the encoding bit-rate problem in H.264 wireless video communication,this paper analyzes the bit-rate computation model and the Mean Square Error distortion model,establishes the relation between the quantization parameter of the encoding bit-rate and the intra frame refresh rate of the macro block,and put forward a new ideal about the coding rate on the basis of general binomial computation model theory. Furthermore,this method not only can adaptively adjust the bit allocation and quantization parameter and prevents buffer from overflowing downward or upward under given network bandwidth,but also can apply the rate-distortion to optimize the solution method,control the encoding bits accurately and optimizes the allocation between the intra and inter frame encoding macro block.     

Blurred Defocused Image Restoration Based on FRFT

A technique for restoring the blurred image resulted from defocusing of the lens is proposed in this paper, which is based on fractional Fourier transform （FRFT）.The FRFT, as a powerful tool for the analysis of time-varying signals, is closely connected with the optical imaging system. FRFT also can describe optical imaging process just like Fresnel diffractions, so a defocused imaging model based on FRFT is established to explain the blur phenomena of defocusing image. The defocused imaging model is greatly different from the traditional point spread function （PSF） model, and enables to uncover the blur nature of non-focus image. Then, an image restoration method using the novel model is proposed to handle the blurred defocused image. The method adopted a new iterative phase retrieval approach which can approximately estimate phase signals from intensity signals of a single defocused image by means of FRFT. Restoring image may acquire sharp image by implementing inverse FRFT on complex image signal made from the estimated phase signals and intensity signals. Experimental results demonstrate that the method is effective in restoring blurred defocused image.     

Stability Analysis of Stochastic Swarm Systems

In this paper,we present a model of stochastic swarm system and prove the stability of this kind of systems. We establish the stable aggregating behavior for the group using a coordination control scheme. This individual-based control scheme is a combination of attractive and repulsive interactions among the individuals in the group,which ensures the cohesion of the group and collision avoidance among the individuals. The dynamics of each individual depends on the relative positions between the individuals and the influences of the random disturbances. Under the influences of the noises,this position-based control strategy still generates the stable aggregating behavior harmoniously for the group and the self-organized swarm pattern is formed.     

Synthesis, Characterization and Calorimetry of Ni（C4H8N2O3）2Cl2

A coordination complex was synthesized from NiCl2 and dipeptide glycylglycine（GG）. It was characterized by element analysis, NMR and TG methods, and then was determined to be Ni（C4HsN2O3）2Cl2. Using an isoperibolic reaction calorimeter, the standard molar enthalpy of formation of Ni（GG）2Cl2（solid） has been determined to be -（1 674.66±2.02） kJ · mol^-1 at 298.15 K.     

Research of Inclusion Complexation of 4,4＇-Thiodiphenol Effected by β-Cyclodextrin in Aqueous Solutions and the Effect on Photodegradation

The inclusion behavior of 4, 4＇ -Thiodiphenol （TDP）, a typical bisphenol and endocrine disruptor, reacts with β-cyclodextrin （β-CD） in aqueous solutions has been investigated by means of UV absorption spectrum and quantum-chemical calculation with Gaussian 98 software. The results show that the inclusion behavior of TDP is quite different in acidic solutions （pH 5.9） from that in alkaline solutions （pH 10.0）. This behavior difference is attributed to the different formula structures in aqueous solutions at acidic and alkaline pH values that are demonstrated by quantum- chemical modeling and calculation. TDP forms a 1 ： 1 fl-CD inclusion complex in aqueous solutions. The equiiibrium constant K was calculated to be 553.49 L/mol at pH 5.9 and 1 318.20 L/mol at pH 10.0 respectively for the inclusion complex reaction by using the modified Benesi-Heldbrand equation. After inclusion TDP＇s structure is changed especially at the inclusion part with the bond order becoming larger, which results in inhibitive photodegradation during direct photooxidation and H2O2 assisted photooxidation.     

Optimizing Conditions of Enhancing Granule Sludge Concentration and Performance

An expanded granular sludge bed （EGSB） reactor was adopted to study the influence factors and rule of enhancing granular sludge concentration and performance. The experiment was performed at 33 ℃, pH 6.0-8.0 with continuous flow by adding proper quantity of nutritional trace elements. The results show that SLR was the key of steady operation of EGSB reactor. The increment of the granular sludge was influenced by volume loading rate （VLR）, liquid up-flow velocity and sludge loading rate （SLR）. Concentration of granular sludge increased rapidly when liquid up-flow velocity was over 0.94 m · h^-1 with SLR being at 1.0-2.0 d ^-1. With the propriety parameters： liquid up-flow velocity 2.52 m · h^-1, SLR 1.0-2.2 d^-1 and VLR 8.2-13.1 kg · m ^3 · d^-1, 23 days＇ continuous operation resulted in an increment by over 80% of granular sludge concentration in the EGSB reactor, plus good granular sludge property.