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Enhanced ultraviolet-B (UV-B) radiation promotes anthocyanin biosynthesis in leaves, flowers and fruits of plants. However, the effects and underlying mechanisms of enhanced UV-B radiation on the accumulation of anthocyanins in the tubers of potatoes (Solanum tuberosum L.) remain unclear. Herein, reciprocal grafting experiments were first conducted using colored and uncolored potatoes, demonstrating that the anthocyanins in potato tubers were synthesized in situ, and not transported from the leaves to the tubers. Furthermore, the enhanced UV-B radiation (2.5 kJ·m−2·d−1) on potato stems and leaves significantly increased the contents of total anthocyanin and monomeric pelargonidin and peonidin in the red-fleshed potato ‘21-1’ tubers, compared to the untreated control. A comparative transcriptomic analysis showed that there were 2139 differentially expressed genes (DEGs) under UV-B treatment in comparison to the control, including 1724 up-regulated and 415 down-regulated genes. The anthocyanin-related enzymatic genes in the tubers such as PAL, C4H, 4CL, CHS, CHI, F3H, F3’5’H, ANS, UFGTs, and GSTs were up-regulated under UV-B treatment, except for a down-regulated F3’H. A known anthocyanin-related transcription factor StbHLH1 also showed a significantly higher expression level under UV-B treatment. Moreover, six differentially expressed MYB transcription factors were remarkably correlated to almost all anthocyanin-related enzymatic genes. Additionally, a DEGs enrichment analysis suggested that jasmonic acid might be a potential UV-B signaling molecule involved in the UV-B-induced tuber biosynthesis of anthocyanin. These results indicated that enhanced UV-B radiation in potato stems and leaves induced anthocyanin accumulation in the tubers by regulating the enzymatic genes and transcription factors involved in anthocyanin biosynthesis. This study provides novel insights into the mechanisms of enhanced UV-B radiation that regulate the anthocyanin biosynthesis in potato tubers.

Aiming at the problem of easy tampering and difficult integrity authentication of paper text documents, this paper proposes a robust content authentication method for printed documents based on text watermarking scheme resisting print-and-scan attack. Firstly, an authentication watermark signal sequence related to content of text document is generated based on the Logistic chaotic map model; then, the authentication watermark signal sequence is embedded into printed paper document by using a robust text watermarking scheme; finally, the watermark information is extracted from scanned image of paper document, and compared with the authentication watermark information calculated in real time by the text document content obtained by OCR technology, thereby performing content integrity authentication of the paper text documents. Experimental results show that our method can achieve the robust content integrity authentication of paper text documents, and can also accurately locate the tampering position. In addition, the document after embedding the watermark information has a good visual effect, and the text watermarking scheme has a large information capacity.

CCN is communication architecture that takes content as a primitive,and retrieves content by name,not by host IP again.It builds on publish/subscribe and network-embedded caching with bandwidth-storage tradeoff.Since it is a clean-slate design,there are many issues to be explored.The concepts,characteristics,network model and recent advances of CCN were introduced.The challenges and some key issues CCN faced were also emphasized.In order to demonstrate the feasibility and implementations,two CCN system samples were also presented.

To understand genetic variation and population dispersal in the Yangtze vole Microtus fortis calamorum distributed in the Dongting Lake region, 144 individuals were collected from six habitat patches. The mitochondrial DNA control region was sequenced and 17 haplotypes were observed. Of the six investigated populations, haplotype and nucleotide diversities of those from larger patches were higher than those from smaller patches. Nonparametric correlation analysis showed that patch size had a positive correlation with haplotype diversity (r = 0.943, P < 0.01). A neighbour-joining tree of the 17 haplotypes showed no geographic genetic structure among the six populations. Analysis of isolation by distance showed that genetic differentiation among the six populations was not positively related to geographic distance. Analysis of mismatch distribution indicated that the voles had passed through a population expansion. The pattern of haplotype distribution in the Changsha population suggests that the population was established by a founder effect [Current Zoology 58 (2): 211–220, 2012].