40 research outputs found

    Random number generation using spontaneous symmetry breaking in a Kerr resonator

    Full text link
    We experimentally demonstrate an all-optical random number generator based on spontaneous symmetry breaking in a coherently-driven Kerr resonator. Random bit sequences are generated by repeatedly tuning a control parameter across a symmetry-breaking bifurcation that enacts random selection between two possible steady-states of the system. Experiments are performed in a fibre ring resonator, where the two symmetry-broken steady-states are associated with orthogonal polarization modes. Detrimental biases due to system asymmetries are completely suppressed by leveraging a recently-discovered self-symmetrization phenomenon that ensures the symmetry breaking acts as an unbiased coin toss, with a genuinely random selection between the two available steady-states. We optically generate bits at a rate of over 3~MHz without post-processing and verify their randomness using the National Institute of Standards and Technology and Dieharder statistical test suites.Comment: 5 pages, 4 figure

    Genome-wide DNA polymorphisms in two cultivars of mei (Prunus mume sieb. et zucc.)

    Get PDF
    BACKGROUND: Mei (Prunus mume Sieb. et Zucc.) is a famous ornamental plant and fruit crop grown in East Asian countries. Limited genetic resources, especially molecular markers, have hindered the progress of mei breeding projects. Here, we performed low-depth whole-genome sequencing of Prunus mume ‘Fenban’ and Prunus mume ‘Kouzi Yudie’ to identify high-quality polymorphic markers between the two cultivars on a large scale. RESULTS: A total of 1464.1 Mb and 1422.1 Mb of ‘Fenban’ and ‘Kouzi Yudie’ sequencing data were uniquely mapped to the mei reference genome with about 6-fold coverage, respectively. We detected a large number of putative polymorphic markers from the 196.9 Mb of sequencing data shared by the two cultivars, which together contained 200,627 SNPs, 4,900 InDels, and 7,063 SSRs. Among these markers, 38,773 SNPs, 174 InDels, and 418 SSRs were distributed in the 22.4 Mb CDS region, and 63.0% of these marker-containing CDS sequences were assigned to GO terms. Subsequently, 670 selected SNPs were validated using an Agilent’s SureSelect solution phase hybridization assay. A subset of 599 SNPs was used to assess the genetic similarity of a panel of mei germplasm samples and a plum (P. salicina) cultivar, producing a set of informative diversity data. We also analyzed the frequency and distribution of detected InDels and SSRs in mei genome and validated their usefulness as DNA markers. These markers were successfully amplified in the cultivars and in their segregating progeny. CONCLUSIONS: A large set of high-quality polymorphic SNPs, InDels, and SSRs were identified in parallel between ‘Fenban’ and ‘Kouzi Yudie’ using low-depth whole-genome sequencing. The study presents extensive data on these polymorphic markers, which can be useful for constructing high-resolution genetic maps, performing genome-wide association studies, and designing genomic selection strategies in mei

    <i>RrGT2</i>, A Key Gene Associated with Anthocyanin Biosynthesis in <i>Rosa rugosa</i>, Was Identified Via Virus-Induced Gene Silencing and Overexpression

    No full text
    In this study, a gene with a full-length cDNA of 1422 bp encoding 473 amino acids, designated RrGT2, was isolated from R. rugosa &#8216;Zizhi&#8217; and then functionally characterized. RrGT2 transcripts were detected in various tissues and were proved that their expression patterns corresponded with anthocyanins accumulation. Functional verification of RrGT2 in R. rugosa was performed via VIGS. When RrGT2 was silenced, the Rosa plants displayed a pale petal color phenotype. The detection results showed that the expression of RrGT2 was significantly downregulated, which was consistent with the decrease of all anthocyanins; while the expression of six key upstream structural genes was normal. Additionally, the in vivo function of RrGT2 was investigated via its overexpression in tobacco. In transgenic tobacco plants expressing RrGT2, anthocyanin accumulation was induced in the flowers, indicating that RrGT2 could encode a functional GT protein for anthocyanin biosynthesis and could function in other species. The application of VIGS in transgenic tobacco resulted in the treated tobacco plants presenting flowers whose phenotypes were lighter in color than those of normal plants. These results also validated and affirmed previous conclusions. Therefore, we speculated that glycosylation of RrGT2 plays a crucial role in anthocyanin biosynthesis in R. rugosa

    Over-Expression of Rose RrLAZY1 Negatively Regulates the Branch Angle of Transgenic Arabidopsis Inflorescence

    No full text
    Branch angle is a key shoot architecture trait that strongly influences the ornamental and economic value of garden plants. However, the mechanism underlying the control of branch angle, an important aspect of tree architecture, is far from clear in roses. In the present study, we isolated the RrLAZY1 gene from the stems of Rosa rugosa &lsquo;Zilong wochi&rsquo;. Sequence analysis showed that the encoded RrLAZY1 protein contained a conserved G&Phi;L (A/T) IGT domain, which belongs to the IGT family. Quantitative real-time PCR (qRT-PCR) analyses revealed that RrLAZY1 was expressed in all tissues and that expression was highest in the stem. The RrLAZY1 protein was localized in the plasma membrane. Based on a yeast two-hybrid assay and bimolecular fluorescence complementation experiments, the RrLAZY1 protein was found to interact with auxin-related proteins RrIAA16. The over-expression of the RrLAZY1 gene displayed a smaller branch angle in transgenic Arabidopsis inflorescence and resulted in changes in the expression level of genes related to auxin polar transport and signal transduction pathways. This study represents the first systematic analysis of the LAZY1 gene family in R. rugosa. The results of this study will provide a theoretical basis for the improvement of rose plant types and molecular breeding and provide valuable information for studying the regulation mechanism of branch angle in other woody plants

    An Improved Contextual Advertising Matching Approach based on Wikipedia Knowledge

    No full text
    The current boom of the Web is associated with the revenues originated from Web advertising. As one prevalent type of Web advertising, contextual advertising refers to the placement of the most relevant commercial textual ads within the content of a Web page, so as to provide a better user experience and thereby increase the revenues of Web site owners and an advertising platform. Therefore, in contextual advertising, the relevance of selected ads with a Web page is essential. However, some problems, such as homonymy and polysemy, low intersection of keywords and context mismatch, can lead to the selection of irrelevant textual ads for a Web page, making that a simple keyword matching technique generally gives poor accuracy. To overcome these problems and thus to improve the relevance of contextual ads, in this paper we propose a novel Wikipedia-based matching technique which, using selective matching strategies, selects a certain amount of relevant articles from Wikipedia as an intermediate semantic reference model for matching Web pages and textual ads. We call this technique SIWI: Selective Wikipedia Matching, which, instead of using the whole Wikipedia articles, only matches the most relevant articles for a page (or a textual ad), resulting in the effective improvement of the overall matching performance. An experimental evaluation is conducted, which runs over a set of real textual ads, a set of Web pages from the Internet and a dataset of more than 260 000 articles from Wikipedia. The experimental results show that our method performs better than existing matching strategies, which can deal with the matching over the large dataset of Wikipedia articles efficiently, and achieve a satisfactory contextual advertising effect

    Risk evaluation of tailings dam based on game theory and matter-extension theory

    No full text
    The safety and stability of tailings dam are directly related to the safety of life and property of downstream residents and the ecological and environmental safety of downstream rivers and farmland. During the operation stage of the tailings pond, safety assessment shall be carried out from seepage damage of the tailings dam, instability of the dam foundation, structural damage of the dam body, flooded roof, and safety management, etc. Aiming at a tailings pond in the running stage of Guangxi Province in China, by establishing the evaluation index system and its grading standard of the tailings dam-break, the subjectivity and objectivity of the evaluation index are taken into consideration by the combination of matter-element extension theory and game theory. Meanwhile, in order to solve the problem of the defect of the correlation function when the eigenvalue exceeds the controlled field and of the incommensurability for different units, a linear dimensionless method is adopted. The results show that the grade of tailings dam-break is I, and the eigenvalue of grade variable is 1.3, that is, the tailings pond is a “normal tailing reservoir”, but there is a risk of evolution to the “sickness tailing reservoir”. Thus, corresponding measures must be taken to prevent. In addition, the result of the two methods is consistent by comparing with the unascertained measure method, which not only validates the accuracy of the evaluation method, but also embodies the unique advantage of possessing the eigenvalue of grade variable to alert its evolution direction

    Functional Divergence Analysis of <i>AGL6</i> Genes in <i>Prunus mume</i>

    No full text
    The AGAMOUS-LIKE6 (AGL6) lineage is an important clade of MADS-box transcription factors that play essential roles in floral organ development. The genome of Prunus mume contains two homoeologous AGL6 genes that are replicated as gene fragments. In this study, two AGL6 homologs, PmAGL6-1 and PmAGL6-2, were cloned from P. mume and then functionally characterized. Sequence alignment and phylogenetic analyses grouped both genes into the AGL6 lineage. The expression patterns and protein–protein interaction patterns showed significant differences between the two genes. However, the ectopic expression of the two genes in Arabidopsis thaliana resulted in similar phenotypes, including the promotion of flowering, alteration of floral organ structure, participation in the formation of the floral meristem and promotion of pod bending. Therefore, gene duplication has led to some functional divergence of PmAGL6-1 and PmAGL6-2 but their functions are similar. We thus speculated that AGL6 genes play a crucial role in flower development in P. mume

    Executing SQL queries over encrypted character strings in the Database-As-Service model

    No full text
    Rapid advances in the networking technologies have prompted the emergence of the “software as service” model for enterprise computing, moreover, which is becoming one of the key industries quickly. “Database as service” model provides users power to store, modify and retrieve data from anywhere in the world, as long as they have access to the Internet, thus, being increasingly popular in current enterprise data management systems. However, this model introduces several challenges, an essential issue being how to implement SQL queries over encrypted data efficiently. To ensure data security, this model generally encrypts sensitive data at the trusted client’s site, before storing them into the non-trusted database service provider’s site, which, unfortunately, results in that SQL queries cannot be executed over the encrypted data immediately at the database service provider. In this paper we only focus on how to query encrypted character strings efficiently. Our strategy is that when storing character strings to the database service provider, we not only store the encrypted character strings themselves, but also generate some characteristic index values for these character strings, and store them in an additional field; and when querying the encrypted character strings, we first execute a coarse query over the characteristic index fields at the database service provider, in order to filter out most of tuples not related to the querying conditions, and then, we decrypt the rest tuples and execute a refined query over them again at the client site. In our strategy, we define an n-phase reachability matrix for a character string and use it as the characteristic index values, and based on such a definition, we present some theorems to split a SQL query into its server-side representation and client-side representation for partitioning the computation of a query across the client and the server and thus improving query performance. Finally, experimental results validate the functionality and effectiveness of our strategy

    Preliminary application of grade equivalent theory in a local section of a mine and economic estimation of the deposit

    No full text
    By introducing the practical application of grade equivalent theory in a copper -cobalt mine, it can show the maximum economic value of the individual ore block and the mine, maximize the comprehensive utilization of limited resources and contains positive significance for extending the service life of the mine. Briefly introducing the steps of Micromine software in the process of reserve estimation and the feasibility of displaying the economic value of individual ore blocks. Estimation of reserve can be completed objectively and scientifically by Micromine software, grade and economic value of ore blocks can be displayed in three-dimensional image

    SEP-class genes in Prunus mume and their likely role in floral organ development

    Get PDF
    Abstract Background Flower phylogenetics and genetically controlled development have been revolutionised during the last two decades. However, some of these evolutionary aspects are still debatable. MADS-box genes are known to play essential role in specifying the floral organogenesis and differentiation in numerous model plants like Petunia hybrida , Arabidopsis thaliana and Antirrhinum majus . SEPALLATA (SEP) genes, belonging to the MADS-box gene family, are members of the ABCDE and quartet models of floral organ development and play a vital role in flower development. However, few studies of the genes in Prunus mume have yet been conducted. Results In this study, we cloned four PmSEPs and investigated their phylogenetic relationship with other species. Expression pattern analyses and yeast two-hybrid assays of these four genes indicated their involvement in the floral organogenesis with PmSEP4 specifically related to specification of the prolificated flowers in P. mume . It was observed that the flower meristem was specified by PmSEP1 and PmSEP4 , the sepal by PmSEP1 and PmSEP4 , petals by PmSEP2 and PmSEP3 , stamens by PmSEP2 and PmSEP3 and pistils by PmSEP2 and PmSEP3 . Conclusion With the above in mind, flower development in P. mume might be due to an expression of SEP genes. Our findings can provide a foundation for further investigations of the transcriptional factors governing flower development, their molecular mechanisms and genetic basis
    corecore