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Link prediction aims to predict unknown links using available network topology information.Prediction methods based on paths perform well in undirected networks.However,paths of the same length have different node connection strength due to different type of links through the path in directed network.Traditional methods is difficult to distinguish the path heterogeneity.Given this,the difference in the strength of three types of directed links is first quantified in terms of the link weight matrix,then the connection strength of different heterogeneous classpaths between nodes is calculated and the effect of different paths under the same length path is distinguished.Finally,a directed network link prediction method based on the path connection strength is proposed by integrating the contribution of multi-order paths of different lengths.Validation of 9 real networks shows that accounting for differences in path connection strength effectively improves prediction performance under the AUC and Precision metrics.

Based on the analysis of the factors that affect retweet behavior, this paper proposed a predict SVM algorithm with five features: user influence, user activity, interest similarity, the importance of micro-blog content and users closeness. Furthermore, it proposed the predict algorithm of retweet scale on the basis of SVM, also, gave a method to evaluate the predict accuracy. The experiment with Sina micro-blog data shows a good result that the predict accuracy is up to 86.63%. [ABSTRACT FROM AUTHOR]

Identification accuracy of traditional Chinese medicine is crucial for the traditional Chinese medicine research, production and application. DNA barcoding based on the mitochondrial gene coding for cytochrome c oxidase subunit I (COI), are more and more used for identification of traditional Chinese medicine. Using universal barcoding primers to sequence, we discussed the feasibility of DNA barcoding method for identification commonly-used medicinal snakes (a total of 109 samples belonging to 19 species 15 genera 6 families). The phylogenetic trees using Neighbor-joining were constructed. The results indicated that the mean content of G + C(46.5%) was lower than that of A + T (53.5%). As calculated by Kimera-2-parameter model, the mean intraspecies genetic distance of Trimeresurus albolabris, Ptyas dhumnades and Lycodon rufozonatus was greater than 2%. Further phylogenetic relationship results suggested that identification of one sample of T. albolabris was erroneous. The identification of some samples of P. dhumnades was also not correct, namely originally P. korros was identified as P. dhumnades. Factors influence on intraspecific genetic distance difference of L. rufozonatus need to be studied further. Therefore, DNA barcoding for identification of medicinal snakes is feasible, and greatly complements the morphological classification method. It is necessary to further study in identification of traditional Chinese medicine.

To identify some medicinal animals of Lacertilia, in total 59 individuals belonging to 12 species 7 genera 3 families, we used the universal barcoding primers to sequence these species, compared with other homologous sequences (564 bp) obtaining from the GenBank and finally constructed phylogenetic trees using Neighbor-joining, Maximum parsimony and Bayesian inference, respectively. As a result, the mean content of G + C (46.5%) was lower than that of A + T (53.5%). As calculated by Kimera-2-parameter model, the whole individuals mean distance for interspecies and intraspecies was 35. 5% and 1.7%, respectively. The mean distance for interspecies was 21 times as much as that for intraspecies. The mean distance for intraspecies of Gekko swinhonis, Hemidactylus frenatus and G. gecko was greater than 2%, respectively. Further analyses suggested that geographical groups of the three species might be of different subSpecies, even species. Of course, incorporating morphological characters and other unlinked genetic markers in future studies will offer further insights into the divergence. On the basis of phylogenetic trees constructed by COI, our results indicated that the taxonomy of the category (family, genus, and species) by DNA barcoding is consistent with morphological characters. Therefore, DNA barcoding is a useful tool for both identification and phylogeny of medicinal animals of Lacertilia, particularly for nonprofessor identifying authentication of Chinese crude drugs of these species.

Objective: To establish HPLC fingerprint of Gekko gecko., Methods: The relative retention time and relative peak area of exteacts of Gekko gecko were determine by HPLC to confirm proper chromatographic condition and obtain the data., Results: Better distribution of relative retention time and relative peak area were shown under the chromatographic condition and the HPLC fingerprint was established., Conclusion: The established HPLC fingerprints of Gekko gecko can be used to identify Gekko gecko and its quality control.