Second generation Dirac cones and inversion symmetry breaking induced gaps in graphene/hexagonal boron nitride

Graphene/h-BN has emerged as a model van der Waals heterostructure, and the band structure engineering by the superlattice potential has led to various novel quantum phenomena including the self-similar Hofstadter butterfly states. Although newly generated second generation Dirac cones (SDCs) are believed to be crucial for understanding such intriguing phenomena, so far fundamental knowledge of SDCs in such heterostructure, e.g. locations and dispersion of SDCs, the effect of inversion symmetry breaking on the gap opening, still remains highly debated due to the lack of direct experimental results. Here we report first direct experimental results on the dispersion of SDCs in 0$^\circ$ aligned graphene/h-BN heterostructure using angle-resolved photoemission spectroscopy. Our data reveal unambiguously SDCs at the corners of the superlattice Brillouin zone, and at only one of the two superlattice valleys. Moreover, gaps of $\approx$ 100 meV and $\approx$ 160 meV are observed at the SDCs and the original graphene Dirac cone respectively. Our work highlights the important role of a strong inversion symmetry breaking perturbation potential in the physics of graphene/h-BN, and fills critical knowledge gaps in the band structure engineering of Dirac fermions by a superlattice potential.Comment: Nature Physics 2016, In press, Supplementary Information include

Preparation of Antibacterial Color-Coated Steel Sheets

A simple method to fabricate antibacterial color-coated steel sheet was presented. The Ag-loaded TiO2 was well dispersed in steel coil coating coupled with some special additives, such as plasticizer, wetting dispersant, and flow agent, and finally became the part of coil coating without any negative influence on the properties of final products. The best process parameters were obtained by substantive trial experiments. Ag-loaded TiO2 with the addition of 2% (w/w) in steel coil coating not only improved antibacterial efficiency of the antibacterial color-coated sheet by reaching 99.99%, but also greatly increased the degradation percentage of methyl orange to 88% without decreasing physical properties. The antibacterial color-coated sheets are expected to be used as antimicrobial products in the construction industry considering its low cost and high effectiveness in inhibiting the growth of bacteria

A quantitative RT-PCR assay for rapid detection of Eurasianlineage H10 subtype influenza A virus

Influenza A viruses (IAVs) are single-stranded, negative sense RNA viruses. IAV subtype is determined on the basis of the viral surface glycoproteins, hemagglutinin (HA), and neuraminidase (NA). To date, 18 HA and 11 NA subtypes have been reported (Tong et al., 2012). IAVs can cause sporadic infections, local epidemics, and global pandemics among humans. In addition to humans, IAVs can naturally infect avian, swine, equines, canines, and sea mammals (Webster et al., 1992). Migratory waterfowl are the natural reservoir for IAVs, and the avianorigin IAVs play an important role in influenza ecology and have been involved in generation of the IAVs infection in humans. At least one or more genetic segments of all four known pandemic strains are of avian origin, and these avian-origin genes reassorted with those IAVs from domestic animals to generate pandemic viruses. For example, the HA genes (major antigenic determinants) of 1918, 1957, and 1968 pandemic viruses are all of avianorigin (Webster et al., 1997); the 2009 H1N1 pandemic virus has avian-origin PB2 and PA genes (Shinde et al., 2009). Besides pandemic viruses, in the past decades, there have also been a number of reported human infections with avian IAVs, including subtypes H5N1, H6N1, H7N2, H7N3, H7N7, H9N2, H10N7 and H7N9. Thus, monitoring the evolution of avian IAVs and rapidly detecting these viruses in human are important components of influenza surveillance and pandemic preparedness

A quantitative RT-PCR assay for rapid detection of Eurasianlineage H10 subtype influenza A virus

Influenza A viruses (IAVs) are single-stranded, negative sense RNA viruses. IAV subtype is determined on the basis of the viral surface glycoproteins, hemagglutinin (HA), and neuraminidase (NA). To date, 18 HA and 11 NA subtypes have been reported (Tong et al., 2012). IAVs can cause sporadic infections, local epidemics, and global pandemics among humans. In addition to humans, IAVs can naturally infect avian, swine, equines, canines, and sea mammals (Webster et al., 1992). Migratory waterfowl are the natural reservoir for IAVs, and the avianorigin IAVs play an important role in influenza ecology and have been involved in generation of the IAVs infection in humans. At least one or more genetic segments of all four known pandemic strains are of avian origin, and these avian-origin genes reassorted with those IAVs from domestic animals to generate pandemic viruses. For example, the HA genes (major antigenic determinants) of 1918, 1957, and 1968 pandemic viruses are all of avianorigin (Webster et al., 1997); the 2009 H1N1 pandemic virus has avian-origin PB2 and PA genes (Shinde et al., 2009). Besides pandemic viruses, in the past decades, there have also been a number of reported human infections with avian IAVs, including subtypes H5N1, H6N1, H7N2, H7N3, H7N7, H9N2, H10N7 and H7N9. Thus, monitoring the evolution of avian IAVs and rapidly detecting these viruses in human are important components of influenza surveillance and pandemic preparedness

A quantitative RT-PCR assay for rapid detection of Eurasianlineage H10 subtype influenza A virus

Influenza A viruses (IAVs) are single-stranded, negative sense RNA viruses. IAV subtype is determined on the basis of the viral surface glycoproteins, hemagglutinin (HA), and neuraminidase (NA). To date, 18 HA and 11 NA subtypes have been reported (Tong et al., 2012). IAVs can cause sporadic infections, local epidemics, and global pandemics among humans. In addition to humans, IAVs can naturally infect avian, swine, equines, canines, and sea mammals (Webster et al., 1992). Migratory waterfowl are the natural reservoir for IAVs, and the avianorigin IAVs play an important role in influenza ecology and have been involved in generation of the IAVs infection in humans. At least one or more genetic segments of all four known pandemic strains are of avian origin, and these avian-origin genes reassorted with those IAVs from domestic animals to generate pandemic viruses. For example, the HA genes (major antigenic determinants) of 1918, 1957, and 1968 pandemic viruses are all of avianorigin (Webster et al., 1997); the 2009 H1N1 pandemic virus has avian-origin PB2 and PA genes (Shinde et al., 2009). Besides pandemic viruses, in the past decades, there have also been a number of reported human infections with avian IAVs, including subtypes H5N1, H6N1, H7N2, H7N3, H7N7, H9N2, H10N7 and H7N9. Thus, monitoring the evolution of avian IAVs and rapidly detecting these viruses in human are important components of influenza surveillance and pandemic preparedness

Experimental observation of topological Fermi arcs in type-II Weyl semimetal MoTe2

Weyl semimetal is a new quantum state of matter [1-12] hosting the condensed matter physics counterpart of relativisticWeyl fermion [13] originally introduced in high energy physics. The Weyl semimetal realized in the TaAs class features multiple Fermi arcs arising from topological surface states [10, 11, 14-16] and exhibits novel quantum phenomena, e.g., chiral anomaly induced negative mag-netoresistance [17-19] and possibly emergent supersymmetry [20]. Recently it was proposed theoretically that a new type (type-II) of Weyl fermion [21], which does not have counterpart in high energy physics due to the breaking of Lorentz invariance, can emerge as topologically-protected touching between electron and hole pockets. Here, we report direct spectroscopic evidence of topological Fermi arcs in the predicted type-II Weyl semimetal MoTe2 [22-24]. The topological surface states are confirmed by directly observing the surface states using bulk-and surface-sensitive angle-resolved photoemission spectroscopy (ARPES), and the quasi-particle interference (QPI) pattern between the two putative Fermi arcs in scanning tunneling microscopy (STM). Our work establishes MoTe2 as the first experimental realization of type-II Weyl semimetal, and opens up new opportunities for probing novel phenomena such as exotic magneto-transport [21] in type-II Weyl semimetals.Comment: submitted on 01/29/2016. Nature Physics, in press. Spectroscopic evidence of the Fermi arcs from two complementary surface sensitive probes - ARPES and STS. A comparison of the calculated band structure for T_d and 1T' phase to identify the topological Fermi arcs in the T_d phase is also included in the supplementary informatio

Long Span DNA Paired-End-Tag (DNA-PET) Sequencing Strategy for the Interrogation of Genomic Structural Mutations and Fusion-Point-Guided Reconstruction of Amplicons

10.1371/journal.pone.0046152PLoS ONE79

Recurrent Fusion Genes in Gastric Cancer: CLDN18-ARHGAP26 Induces Loss of Epithelial Integrity.

Genome rearrangements, a hallmark of cancer, can result in gene fusions with oncogenic properties. Using DNA paired-end-tag (DNA-PET) whole-genome sequencing, we analyzed 15 gastric cancers (GCs) from Southeast Asians. Rearrangements were enriched in open chromatin and shaped by chromatin structure. We identified seven rearrangement hot spots and 136 gene fusions. In three out of 100 GC cases, we found recurrent fusions between CLDN18, a tight junction gene, and ARHGAP26, a gene encoding a RHOA inhibitor. Epithelial cell lines expressing CLDN18-ARHGAP26 displayed a dramatic loss of epithelial phenotype and long protrusions indicative of epithelial-mesenchymal transition (EMT). Fusion-positive cell lines showed impaired barrier properties, reduced cell-cell and cell-extracellular matrix adhesion, retarded wound healing, and inhibition of RHOA. Gain of invasion was seen in cancer cell lines expressing the fusion. Thus, CLDN18-ARHGAP26 mediates epithelial disintegration, possibly leading to stomach H(+) leakage, and the fusion might contribute to invasiveness once a cell is transformed. Cell Rep 2015 Jul 14; 12(2):272-285