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In this paper, stable and homogeneous feather keratin was effectively extracted from feathers. Its molecular weight is 20kDa with low dispersivity. The extracted feather keratin (FK) and its derivatives (FK-ET) were used as natural polymer flocculants. It was a new kind of effective and innoxious flocculant for the COD removal of potato starch wastewater. The removal rate of COD was up to 75% under the following optimal condition: 100mL of initial wastewater (COD = 7380), T = 20°C, [FK-ET] = 0.4g/L, [Bent] = 4g/L, pH = 8.0. Compared with traditional flocculants, keratin flocculants are innoxious natural polymers. Their sludge is easy to be treated, and there is no further pollution. Also, the flocculating constituents, which containing keratin, starch, saccharide, protein and other solubility substances from wastewaters, should be reutilized. It has practical application value in water treatment as a kind of natural polymer flocculant.

The Magnesium Niobate-Lead Titanate (PMN) / conductive carbon black (CB)/ chlorobutyl rubber(CIIR) composites were prepared by blending-vulcanization method, and the dielectric properties were studied. The results showed that the dielectric constant and dielectric loss of composites increased nonlinearly when increasing the content of PMN or CB. From the curve of dielectric constant vs frequency, it is obtained that in the frequency range from 103 to 106 Hz, the dielectric constant of PMN/CB/CIIR composites decreased with the frequency increasing and the dielectric constants are more stable under high frequency.

Constrained Delaunay Triangular Irregular Networks (CD-TIN), a kind of special data structure, have many practical applications in Geoinformatics, especially in the representation of linear constrained triangulation for DTM and DSM, such as in digital city and digital mine. Past researches on D-TIN mainly focused on point insertion and deletion without consideration of constraint, and that on CD-TIN usually paid more attention to the insertion algorithms for points and edges, but little to the deletion algorithms. The presented algorithms are far insufficient for the dynamic updating of CD-TIN. In this paper, the constraint edge in CD-TIN is considered to be any set of broken lines, i.e., polygon edges, broken lines and simple segments. The constraint edge may be composed of one or more constraint segments, and it is allowed to be in any form: Open or close, intersection or self-intersection. By improving to present insertion and deletion algorithms for D-TIN, two new algorithms for CD-TIN updating are presented. According to the polymorphism of the constraints in CD-TIN, virtual point is adopted to represent the crossing node between constraint edges when a constraint edge is inserted in CD-TIN. Two new algorithms named as Integral Ear Elimination (IEE) and Influence Domain Retriangulation for Virtual Point (IDRVP) are presented, the former is for constraint point deletion, while the later is for the insertion and deletion of constraint edge. The principle of IDRVP is that to divide the influence domain of a virtual point into some parts by the constraint-keeping edges, and to retriangulate each part of the influence domain individually referring to the constraint visible property and constraint empty circle (CEC) criterion. Finally, a prototype system is developed with VC++, one case on the integration of 3D terrain and buildings is demonstrated to test the correctness of new algorithms. It shows that the new algorithms are effective for the updating of CD-TIN.

In this paper, a three-phase composite with electrically conductive carbon black (ECCB) and piezoelectric ceramic particles, PMN, embedded into butyl (PMN/ECCB/IIR) was prepared by simple blend and mold-press process. Dynamic mechanical properties with various ECCB loading were tested by dynamic mechanical analysis (DMA). DMA shows that the ECCB loading has remarkable effect on the dynamic mechanical properties of the three-phase composite. The temperature range of loss factor (tanδ) above 0.3 the composite was broadened by almost 100°C and the maximum of loss factor shifts to higher temperature in the testing temperature range respectively with increasing the ECCB loading. The piezoelectric damping theory was used to explain the experimental results. The three-phase composites with proper composition can be used as high damping polymer materials.

Aiming at spatial characteristics and echo information of the LiDAR point cloud data, design a regional segmentation and decision tree combined lidar point data classification method. First, based on the continuity of the LiDAR point cloud to finish the experiment area's region segmentation. Then, statistics each area boundaries and internal the number of dihedral angle cosine, to draw a line chart. Using the intersection's cosine of line chart , and region segmentation's minimum height as threshold to determine the ground point and the non-ground points. Finally, statistics separately all LiDAR point data set's dihedral angle, echo times, echo intensity, mean elevation, four constraint information to build a decision tree to determine which type of feature vesting each divided region. Using classification confusion matrix to assess the classification's accuracy, overall accuracy is higher than 94%. Experimental results show that this method can effectively separate roads, trees, buildings and terrain.

The present paper,on the basis of analyzing the terrain scattering characteristics, proposed a novel supervised classification method combined with complex Wishart classifier ideology. This method used coherent matrix which almost contains all the polarization information to make subsequent adjustments for the supervised classification result to achieve higher accuracy division categories. For the first beginning, supervised classification was carried out on the CloudePottier polarimetric characteristics combination to get the initial classification result. Then, in order to achieve the purpose to correct the mistakes resulting from just using the spatial distribution of feature vectors in supervised classification, we did some analysis as follow. The accuracy analysis of the classification results and the analysis of study area feature scattering similarity play an important role in our study to help us make the determination that the pixels need to be adjusted. Furthermore, taking the mean value of each category coherence matrix as the initial cluster centers of subsequent iterations, and using Kernel Fuzzy C-Means algorithm to adjust the fixed pixel set categories by subsequent category iterative correction, the fine and high-accuracy classification results were obtained, combined with complex Wishart distribution of coherence matrix. The domestic X-band full polarization SAR data of Lingshui area in Hainan province was applied in this classification experiment. The experiment results demonstrate that the proposed method can obtain a favorable classification accuracy polarization SAR image classification results, and better meet the scattering characteristics of the surface objects compared to the original method.

The excessive mining for underground water is the main reason inducing the land subsidence in Beijing, while, increasing of load brought by the urban construction aggravate the local land subsidence in a certain degree. As an international metropolis, the problems of land subsidence that caused by urban construction are becoming increasingly highlights, so revealing the relationship between regional load increase and the response of land subsidence also becomes one of the key problems in the land subsidence research field. In order to analyze the relationship between the load changes in construction and the land subsidence quantitatively, the present study selected the TM remote sensing image covering Beijing plain and used Erdas Modeler tool to invert the index based on building site (IBI), acquired the spatial and temporal change information in research area further; Based on results monitored by PS-InSAR (permanent scatterer interferometry) and IBI index method, and combined with the GIS spatial analysis method in the view of pixels in different scales, this paper analyzes the correlation between typical area load change and land subsidence, The conclusions show that there is a positive correlation between the density of load and the homogeneity of subsidence, especially in area which has a high sedimentation rate. Owing to such characteristics as the complexity and hysteretic nature of soil and geological structure, it is not obvious that the land subsidence caused by the increase of load in a short period. But with the increasing of local land load made by high density buildings and additional settlement of each monomer building superposed with each other, regional land subsidence is still a question that cannot be ignored and needs long-term systematic research and discussion.

Growing evidence has revealed high heterogeneity of fine root networks in both structure and function, with different root orders corporately maintaining trees' physiological activities. However, little information is available on how fine root heterogeneity of trees responds to environmental stresses. We examined concentrations of seven potentially toxic metals (Cr, Ni, Cu, Zn, As, Cd, and Pb) within fine root networks and their correlations with root morphological and macro-elemental traits in six Chinese subtropical trees. The contributions of different orders of roots to fine-root metal storage and return were also estimated. Results showed no consistent pattern for the correlation among different metal concentration against root traits. Unlike root metal concentration that generally decreased with root order, root metal storage was commonly lowest in middle root orders. Root senescence was at least comparable to leaf senescence contributing to metal removal. Although the first-order roots constituted 7.2-22.3% of total fine root biomass, they disproportionately contributed to most of metal return fluxes via root senescence. The two distinct root functional modules contributed differentially to metal uptake, allocation, and return, with defensive (lower-order) roots effectively stabilizing and removing toxic metals and bulk buffering (higher-order) roots possessing a persistent but diluted metal pool. Our results suggest a strong association of physiological functions of metal detoxification and metal homeostasis with the structural heterogeneity in fine root architecture.

Control over cell-material surface interactions is the key to many new and improved biomedical devices. In this study, we present a simple yet effective surface modification method that allows for the surface reconstruction and formation of cell outer membrane mimetic structure on coatings that have significantly increased hemocompatibility. To achieve this, a phosphorylcholine end-capped poly(butylene succinate) (PBS-PC) was synthesized and dip-coated on coverslips. The surface structure of the amphiphilic PBS-PC film was reconstructed by heating in a vacuum oven to obtain the less hydrophilic surface and by immersing in hot water to obtain the more hydrophilic surface. Significant changes in the surface element concentration were observed by X-ray photoelectron spectroscopy analysis and changes in surface wettability were measured by sensitive dynamic contact angle technique. Scanning electron microscope images showed different morphologies of the reconstructed surfaces. Interestingly, the reconstruction between the less hydrophilic and more hydrophilic surfaces is reversible. More importantly, both the reconstructed surfaces are stable in room condition for more than 6 months, and both the surfaces show significant improvement in hemocompatibility as revealed by protein adsorption and platelet adhesion measurements. This reversible surface reconstruction strategy and the interesting results may be significant for fabricating stable and hemocompatible surfaces on differently shaped biomedical devices.

With the rapid development of database technique and computer technology nowadays, it is no longer a difficult problem to manage mass statistical data with computer and database system. However, from the statistical mode and time series of rural socio-economic statistical survey, we know that the statistical data have both spatial and temporal attribute, so the traditional systems have no enough ability to manage and analyze the statistical data with spatio-temporal attribute. In this paper, on the basis of the former research and the real demands of rural socio-economic statistic department, four key techniques about the construction of spatial management and analysis system for rural socioeconomic statistic data were designed. Based on the statistical spatio-temporal database, historical statistical data spatio-temporal division, statistical model library, exploratory spatial statistical analysis method techniques, the integrative operational system was realized for spatio-temporal data management, analysis and thematic mapping or expression. It could be utilized in many aspects of operational work of rural socio-economic statistic administration.

To investigate the enhancement of Lagurus lagurus zona pellucida 3 gene (lzp3) immunization induced by molecular adjuvant C3d in comparison with plasmid pcDNA3-LZP3 (pcD-L) in non-C3d fused form, the eukaryotic expression vector pcDNA3-LZP3-C3d3 (pcD-LC) including lzp3 and three copies of C3d in fusion form was constructed. In vitro,RT-PCR and Western blot showed that lzp3 mRNA and protein were expressed in HeLa cells transfected with pcD-L and pcD-LC, respectively. In vivo,the result of ELISA showed that NIH female mice vaccined with pcD-LC elicited higher titer, longer lasting anti-LZP3 antibody than non-C3d fused form pcD-L (P0.05) by intramuscular gene immunization. MTT analysis indicated that the lymphocytes proliferation response of the pcD-LC primed mice was significantly stronger than that of the blank plasmid injected mice. Antifertility experiment showed that pcD-LC had enhanced effect on blocking fertility of mice (P0.05) with no disruption of follicular development. These results proved that C3d enhanced immune responses induced by lzp3 vaccine and antifertility effect,and provided the basis for the future study of the Lagurus lagurus reproductive controlling.

To improve prokaryotic expression level of Lagurus lagurus zona pellucida 3(LZP3) gene.The rare codons of LZP3 gene fragment were turned into the most frequently used codons in E. coli by overlap PCR. LZP3 gene and mutated LZP3 (LZP3m) gene were cloned into expression vector pGEX4T-1 respectively, and transformed into E. coli BL21(DE3).The expression level of LZP3m was notably higher than that of LZP3.The expression of LZP3 gene in E. coli could be successfully improved by using codon optimization.

Blood compatibility is a critical requirement for materials to be used in medical applications. We describe here a simple and robust method to enhance the biocompatibility of chitosan (CS) surfaces, using random copolymers (PMT) of 2-methacryloyloxyethyl phosphorylcholine (MPC) and trimethoxysilylpropyl methacrylate (TSMA, 6, 14, and 25 mol%) synthesized by free radical copolymerization. The copolymers dissolved in methanol were dip-coated on CS films. The PMT coatings were anchored on CS surfaces during the coating process by covalent bonding of the trimethoxysilane groups with surface amine and/or hydroxyl groups of CS. The composite films were stabilized by crosslinking of the copolymers via amine-catalyzed reactions of the trimethoxysilane groups and further heating (110 °C). Analysis of the PMT-modified CS surfaces by X-ray photoelectron spectroscopy and contact angle measurements indicated that the zwitterionic PC groups were located on or near the film outer surface, which mimics the structure of the cell outer membrane. Film stability studies indicated that PMT copolymers containing 14 mol% TSMA units were linked permanently to CS, whereas PMTs of lower TSMA content were released from the films upon prolonged soaking in water. The CS-PMT (14% TSMA) composite films possessed excellent hemocompatibility, as confirmed by a 60% decrease in protein (bovine serum albumin or fibrinogen) adsorption and a 96% suppression of platelet adhesion, compared to CS films. This simple and stable coating strategy should be useful in a variety of biomedical applications including drug delivery, tissue engineering, stent coatings, and implantable medical devices.

We introduce a new algorithm to analyze recursive, structured types. It derives information from object uses (accesser functions with type checking), as well as from object allocation. The type description is a form of graph grammar and is naturally finite even in the presence of loops. The intended use of the algorithm is to discover and remove unnecessary type checks, but it can be augmented to provide alias information as well.