3,222 research outputs found

    Beating the classical precision limit with spin-1 Dicke state of more than 10000 atoms

    Get PDF
    Interferometry is a paradigm for most precision measurements. Using NN uncorrelated particles, the achievable precision for a two-mode (two-path) interferometer is bounded by the standard quantum limit (SQL), 1/N1/\sqrt{N}, due to the discrete (quanta) nature of individual measurements. Despite being a challenging benchmark, the two-mode SQL has been approached in a number of systems, including the LIGO and today's best atomic clocks. Employing multi-mode interferometry, the SQL becomes 1/[(M1)N]1/[(M-1)\sqrt{N}] using M modes. Higher precision can also be achieved using entangled particles such that quantum noises from individual particles cancel out. In this work, we demonstrate an interferometric precision of 2.421.29+1.762.42^{+1.76}_{-1.29}\,dB beyond the three-mode SQL, using balanced spin-1 (three-mode) Dicke states containing thousands of entangled atoms. The input quantum states are deterministically generated by controlled quantum phase transition and exhibit close to ideal quality. Our work shines light on the pursuit of quantum metrology beyond SQL.Comment: 11 pages, 6 figure

    Storage of multiple single-photon pulses emitted from a quantum dot in a solid-state quantum memory

    Full text link
    Quantum repeaters are critical components for distributing entanglement over long distances in presence of unavoidable optical losses during transmission. Stimulated by Duan-Lukin-Cirac-Zoller protocol, many improved quantum-repeater protocols based on quantum memories have been proposed, which commonly focus on the entanglement-distribution rate. Among these protocols, the elimination of multi-photons (multi-photon-pairs) and the use of multimode quantum memory are demonstrated to have the ability to greatly improve the entanglement-distribution rate. Here, we demonstrate the storage of deterministic single photons emitted from a quantum dot in a polarization-maintaining solid-state quantum memory; in addition, multi-temporal-mode memory with 11, 2020 and 100100 narrow single-photon pulses is also demonstrated. Multi-photons are eliminated, and only one photon at most is contained in each pulse. Moreover, the solid-state properties of both sub-systems make this configuration more stable and easier to be scalable. Our work will be helpful in the construction of efficient quantum repeaters based on all-solid-state devicesComment: Published version, including supplementary materia

    Seroprevalence of Toxoplasma gondii infection in pet dogs in Kunming, Southwest China

    Get PDF
    BACKGROUND: Toxoplasmosis is a zoonotic parasitic disease caused by the protozoan Toxoplasma gondii, which infects almost all warm-blooded animals, including humans, with a worldwide distribution. However, little is known of T. gondii seroprevalence in pet dogs in Kunming, the capital of Yunnan Province, southwest China. The objective of this investigation was to estimate the seroprevalence of T. gondii infection in pet dogs in this area. METHODS: A total of 611 serum samples were collected from 7 pet hospitals in Kunming, and assayed for T. gondii antibodies by the indirect haemagglutination (IHA) using a commercially-marked kit. RESULTS: 132 (21.6%) pet dogs were positive for T. gondii antibodies, and the seroprevalence ranged from 17.3% to 34.7% among different sampling regions, the difference was statistically significant (P < 0.05). The T. gondii seroprevalence in female and male dogs were 20.8% and 22.4%, respectively, the difference was not statistically significant (P > 0.05). The seroprevalence ranged from 17.5% to 23.6% among different age groups, but the difference was not statistically significant (P > 0.05), and there were no interactions in statistics (P > 0.05) between gender and age of pet dogs in the region. CONCLUSIONS: The findings of the present survey indicate high T. gondii seroprevalance in pet dogs in Kunming, southwest China, posing significant public health concern. It is necessary to enhance integrated strategies and measures to prevent and control T. gondii infection in pet dogs in this area

    Toxocara canis Differentially Affects Hepatic MicroRNA Expression in Beagle Dogs at Different Stages of Infection

    Get PDF
    Toxocara canis is a neglected zoonotic parasite, which threatens the health of dogs and humans worldwide. The molecular mechanisms that underlie the progression of T. canis infection remain mostly unknown. MicroRNAs (miRNAs) are small non-coding RNAs that have been identified in T. canis; however, the regulation and role of miRNAs in the host during infection remain incompletely understood. In this study, we determined hepatic miRNA expression at different stages of T. canis infection in beagle dogs. Individual dogs were infected by 300 embryonated T. canis eggs, and their livers were collected at 12 hpi (hours post-infection), 24 hpi, and 36 dpi (days post-infection). The expression profiles of liver miRNAs were determined using RNA-sequencing. Compared to the control groups, 9, 16, and 34 differentially expressed miRNAs (DEmiRNAs) were detected in the livers of infected dogs at the three infection stages, respectively. Among those DEmiRNAs, the novel-294 and cfa-miR-885 were predicted to regulate inflammation-related genes at the initial stage of infection (12 hpi). The cfa-miR-1839 was predicted to regulate the target gene TRIM71, which may influence the development of T. canis larvae at 24 hpi. Moreover, cfa-miR-370 and cfa-miR-133c were associated with immune response at the final stage of infection (36 dpi). Some immunity-related Gene Ontology terms were enriched particularly at 24 hpi. Likewise, Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that many significantly enriched pathways were involved in inflammation and immune responses. The expression level of nine DEmiRNAs was validated using quantitative real-time PCR (qRT-PCR). These results show that miRNAs play critical roles in the pathogenesis of T. canis during the hepatic phase of parasite development. Our data provide fundamental information for further investigation of the roles of miRNAs in the innate/adaptive immune response of dogs infected by T. canis

    Maintaining Internal Consistency of Report for Real-time OLAP with Layer-based View

    Get PDF
    Maintaining internal consistency of report is an important aspect in the field of real-time data warehouses. OLAP and Query tools were initially designed to operate on top of unchanging, static historical data. In a real-time environment, however, the results they produce are usually negatively influenced by data changes concurrent to query execution, which may result in some internal report inconsistency. In this paper, we propose a new method, called layer-based view approach, to appropriately and effectively maintain report data consistency. The core idea is to prevent the data involved in an OLAP query from being changed through using lock mechanism, and avoid the confliction between read and write operations with the help of layer mechanism. Our approach can effectively deal with report consistency issue, while at the same time avoiding the query contention between read and write operations under real-time OLAP environment

    Individuals with psychometric schizotypy show similar social but not physical anhedonia to patients with schizophrenia

    Get PDF
    Very few studies have examined physical and social anhedonia across the spectrum of schizophrenia. In the present study, we recruited three groups of participants (n=84 in each group): patients with schizophrenia, schizotypy and non-schizotypy as assessed by the Schizotypal Personality Questionnaire (SPQ). All participants completed the self-reported trait anhedonia scales (the Revised Physical Anhedonia Scale and the Social Anhedonia Scale). The clinical symptoms of schizophrenia patients were assessed using the Positive and Negative Syndrome Scale (PANSS) and the Scale for Assessment of Negative Symptoms (SANS). We found that the three groups differed in both physical and social anhedonia. The schizotypy group reported higher levels of physical anhedonia than the non-schizotypy group, and the patient group reported higher levels of physical anhedonia than the schizotypy group. For social anhedonia, the non-schizotypy group differed significantly from both the schizotypy and the patient group, while no significant difference was found between the last two groups. Our findings show that individuals with schizotypy exhibits similar social but not physical anhedonia compared with patients with schizophrenia, which further suggests that decreased pleasure experiences in the social environment may be a valuable target for identification and early intervention in high-risk populations, (C) 2014 Elsevier Ireland Ltd. All rights reserved

    Chalcogenide Glass-on-Graphene Photonics

    Get PDF
    Two-dimensional (2-D) materials are of tremendous interest to integrated photonics given their singular optical characteristics spanning light emission, modulation, saturable absorption, and nonlinear optics. To harness their optical properties, these atomically thin materials are usually attached onto prefabricated devices via a transfer process. In this paper, we present a new route for 2-D material integration with planar photonics. Central to this approach is the use of chalcogenide glass, a multifunctional material which can be directly deposited and patterned on a wide variety of 2-D materials and can simultaneously function as the light guiding medium, a gate dielectric, and a passivation layer for 2-D materials. Besides claiming improved fabrication yield and throughput compared to the traditional transfer process, our technique also enables unconventional multilayer device geometries optimally designed for enhancing light-matter interactions in the 2-D layers. Capitalizing on this facile integration method, we demonstrate a series of high-performance glass-on-graphene devices including ultra-broadband on-chip polarizers, energy-efficient thermo-optic switches, as well as graphene-based mid-infrared (mid-IR) waveguide-integrated photodetectors and modulators

    Wolfberry genomes and the evolution of Lycium (Solanaceae)

    Get PDF
    AbstractWolfberry Lycium, an economically important genus of the Solanaceae family, contains approximately 80 species and shows a fragmented distribution pattern among the Northern and Southern Hemispheres. Although several herbaceous species of Solanaceae have been subjected to genome sequencing, thus far, no genome sequences of woody representatives have been available. Here, we sequenced the genomes of 13 perennial woody species of Lycium, with a focus on Lycium barbarum. Integration with other genomes provides clear evidence supporting a whole-genome triplication (WGT) event shared by all hitherto sequenced solanaceous plants, which occurred shortly after the divergence of Solanaceae and Convolvulaceae. We identified new gene families and gene family expansions and contractions that first appeared in Solanaceae. Based on the identification of self-incompatibility related-gene families, we inferred that hybridization hotspots are enriched for genes that might be functioning in gametophytic self-incompatibility pathways in wolfberry. Extremely low expression of LOCULE NUBER (LC) and COLORLESS NON-RIPENING (CNR) orthologous genes during Lycium fruit development and ripening processes suggests functional diversification of these two genes between Lycium and tomato. The existence of additional flowering locus C-like MADS-box genes might correlate with the perennial flowering cycle of Lycium. Differential gene expression involved in the lignin biosynthetic pathway between Lycium and tomato likely illustrates woody and herbaceous differentiation. We also provide evidence that Lycium migrated from Africa into Asia, and subsequently from Asia into North America. Our results provide functional insights into Solanaceae origins, evolution and diversification.</jats:p

    The Euscaphis japonica genome and the evolution of malvids

    Get PDF
    Malvids is one of the largest clades of rosids, includes 58 families and exhibits remarkable morphological and ecological diversity. Here, we report a high-quality chromosome-level genome assembly for Euscaphis japonica, an early-diverging species within malvids. Genome-based phylogenetic analysis suggests that the unstable phylogenetic position of E. japonica may result from incomplete lineage sorting and hybridization event during the diversification of the ancestral population of malvids. Euscaphis japonica experienced two polyploidization events: the ancient whole genome triplication event shared with most eudicots (commonly known as the c event) and a more recent whole genome duplication event, unique to E. japonica. By resequencing 101 samples from 11 populations, we speculate that the temperature has led to the differentiation of the evergreen and deciduous of E. japonica and the completely different population histories of these two groups. In total, 1012 candidate positively selected genes in the evergreen were detected, some of which are involved in flower and fruit development. We found that reddening and dehiscence of the E. japonica pericarp and long fruit-hanging time promoted the reproduction of E. japonica populations, and revealed the expression patterns of genes related to fruit reddening, dehiscence and abscission. The key genes involved in pentacyclic triterpene synthesis in E. japonica were identified, and different expression patterns of these genes may contribute to pentacyclic triterpene diversification. Our work sheds light on the evolution of E. japonica and malvids, particularly on the diversification of E. japonica and the genetic basis for their fruit dehiscence and abscission.DATA AVAILABILITY STATEMENT : All sequences described in this manuscript have been submitted to the National Genomics Data Center (NGDC). The raw whole-genome data of E. japonica have been deposited in BioProject/GSA (https://bigd.big.ac.cn/gsa.) under the accession codes PRJCA005268/CRA004271, and the assembly and annotation data have been deposited at BioProject/GWH (https://bigd.big.ac.cn/gwh) under the accession codes PRJCA005268/GWHBCHS00000000. The raw transcriptomes data of E. japonica have been deposited in BioProject/GSA (https://bigd.big.ac.cn/gsa.) under the accession codes PRJCA005298/CRA004272.SUPPLEMENTARY MATERIAL 1: Supplementary Note 1. Chromosome number assessment. Supplementary Note 2. Whole-genome duplication identification and dating. Supplementary Note 3. Observation of E. japonica seed dispersal. Supplementary Note 4. Determination of pentacyclic triterpene substances. Figure S1. Cytogenetic analysis of E. japonica. Figure S2. Genome size and heterozygosity of E. japonica estimation using 17 k-mer distribution. Figure S3. Interchromosomal of Hi-C chromosome contact map of E. japonica genome. Figure S4. Gene structure prediction results of E. japonica and other species. Figure S5. Venn diagram shows gene families of malvids. Figure S6. Phylogenetic tree constructed by chloroplast genomes from 17 species. Figure S7. Concatenated- and ASTRAL-based phylogenetic trees. Figure S8. Ks distribution in E. japonica. Figure S9. Distributions of synonymous substitutions per synonymous site (Ks) of one-to-one orthologs identified between E. japonica and P. trichocarpa and V. vinifera. Figure S10. Population structure plot. Figure S11. Fixation index (FST) heat map among E. japonica populations. Figure S12. Phylogenetic analysis of MADS-box genes from O. sativa, A. thaliana, E. japonica, and T. cacao. Figure S13. Observation the fruit development. Figure S14. Animal seed dispersal. Figure S15. Anthocyanin biosynthesis in E. japonica fruits. Figure S16. Carotenoid accumulation and the chlorophyll degradation in E. japonica fruits. Figure S17. Expression profile of fruit dehiscence-related genes. Figure S18. Phylogenetic tree of DELLA genes obtained from six malvids species. Figure S19. Phylogenetic tree of CAD genes obtained from seven malvids species. Figure S20. Expression pattern of fruit abscission-related genes. Figure S21. Structure of pentacyclic triterpene compounds separated from Euscaphis. Figure S22. Phylogenetic tree of HMGR gene in plants. Figure S23. Phylogenetic tree of P450s gene family obtained from A. thaliana and E. japonica.SUPPLEMENTARY MATERIAL 2: Table S1. Assembled statistics of E. japonica genome. Table S2. Evaluation of E. japonica genome assembly. Table S3. Chromosome length of E. japonica. Table S4. Prediction of gene structures of the E. japonica genome. Table S5. Statistics on the function annotation of the E. japonica genome. Table S6. Non-coding RNA annotation results of E. japonica genome. Table S7. BUSCO assessment of the E. japonica annotated genome. Table S8. Statistic of repeat sequence in E. japonica genome. Table S9. Gene-clustering statistics for 17 species. Table S10. KEGG enrichment result of unique genes families of E. japonica. Table S11. Gene Ontology (GO) and KEGG enrichment result of significant shared by malvids species gene families. Table S12. Gene Ontology (GO) and KEGG enrichment result of significant expansion of E. japonica gene families. Table S13. Gene Ontology (GO) enrichment result of significant contraction of E. japonica gene families. Table S14. Statistical sampling population information. Table S15. Statistics population resequencing information. Table S16. Statistical nucleotide polymorphisms in the populations. Table S17. Candidate positive selection genes (PSGs) in the evergreen population. Table S18. Candidate positive selection genes (PSGs) in the deciduous population. Table S19. Gene Ontology (GO) enrichment result of significant PSGs in the evergreen population. Table S20. List of MADS-box genes identified in E. japonica. Table S21. Genes involved in anthocyanin biosynthesis, carotenoid biosynthesis, and chlorophyll degradation. Table S22. Identification fruit dehiscence-related genes in E. japonica. Table S23. Genes related to lignin synthesis that are highly expressed during pericarp dehiscence. Table S24. Gene expression levels (FPKMs) of fruit abscission-related genes in pericarp. Table S25. Triterpene compounds separated from Euscaphis. Table S26. Number of putative pentacyclic triterpene-related genes in the malvids species. Table S27. Identified pentacyclic triterpene synthesis-related genes in E. japonica genome. Table S28. Statistical simple sequence repeat.Fund for Excellent Doctoral Dissertation of Fujian Agriculture and Forestry University, China; Fujian Provincial Department of Science E. japonica Evolution and Selection of Ornamental Medicinal Resources, China; the Project of Forestry Peak Discipline at Fujian Agriculture and Forestry University, China; the Collection, Development and Utilization of Eascaphis konlshli Germplasm Resources; the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program and from Ghent University.https://onlinelibrary.wiley.com/journal/1365313xam2022BiochemistryGeneticsMicrobiology and Plant Patholog
    corecore