Topological massive Dirac edge modes and long-range superconducting Hamiltonians

We discover novel topological effects in the one-dimensional Kitaev chain modified by long-range Hamiltonian deformations in the hopping and pairing terms. This class of models display symmetry-protected topological order measured by the Berry/Zak phase of the lower-band eigenvector and the winding number of the Hamiltonians. For exponentially decaying hopping amplitudes, the topological sector can be significantly augmented as the penetration length increases, something experimentally achievable. For power-law decaying superconducting pairings, the massless Majorana modes at the edges get paired together into a massive nonlocal Dirac fermion localized at both edges of the chain: a new topological quasiparticle that we call topological massive Dirac fermion. This topological phase has fractional topological numbers as a consequence of the long-range couplings. Possible applications to current experimental setups and topological quantum computation are also discussed

X-ray nanoimaging of Nd3+ optically active ions embedded in Sr0.5Ba0.5Nb2O6 nanocrystals

[EN] The spatial distribution of Sr0.5Ba0.5Nb2O6 nanocrystals is analyzed in a borate-based glass-ceramic by a synchrotron hard X-ray nanoimaging tool. Based on X-ray excited optical luminescence, we examined 2D projections of the Nd3+ optically active ions in the Sr0.5Ba0.5Nb2O6 nanocrystals, as well as in the glassy phase where they are embedded. Our findings reveal areas of agglomerations and/or clusters of nanocrystals ascribed to the diffusion coefficients of their constituent elements. They are characterized by high Nd3+ concentrations that may act as heterogeneous agents for the nucleation and growth of these nanocrystals. (C) 2017 Optical Society of AmericaMINECO, EU-FEDER and CSIC through the projects MAT2013-46649-C4-4-P, MAT201571070-REDC, MAT2016-75586-C4-2-P, MAT2016-75586-C4-4-P, 201550I021 and 201660I001, respectively. JAS acknowledges the Spanish Program Ramón y Cajal for his fellowship. We also thank the ESRF for the beam time allocated and experimental facilities.Martínez-Criado, G.; Alén, B.; Sans-Tresserras, JÁ.; Lozano-Gorrín, A.; Haro-González, P.; Martin, I.; Lavin, V. (2017). X-ray nanoimaging of Nd3+ optically active ions embedded in Sr0.5Ba0.5Nb2O6 nanocrystals. Optical Materials Express. 7(7):2424-2431. https://doi.org/10.1364/OME.7.002424S2424243177Nagata, K., Yamamoto, Y., Igarashi, H., & Okazaki, K. (1981). Properties of the hot-pressed strontium barium niobate ceramics. Ferroelectrics, 38(1), 853-856. doi:10.1080/00150198108209556Imai, T., Yagi, S., Yamazaki, H., & Ono, M. (1999). Effects of Heat Treatment on Photorefractive Sensitivity of Ce- and Eu-Doped Strontium Barium Niobate. Japanese Journal of Applied Physics, 38(Part 1, No. 4A), 1984-1988. doi:10.1143/jjap.38.1984Volk, T., Isakov, D., Salobutin, V., Ivleva, L., Lykov, P., Ramzaev, V., & Wöhlecke, M. (2004). Effects of Ni doping on properties of strontium–barium–niobate crystals. Solid State Communications, 130(3-4), 223-226. doi:10.1016/j.ssc.2004.01.039Romero, J. J., Andreeta, M. R. B., Andreeta, E. R. M., Bausá, L. E., Hernandes, A. C., & García Solé, J. (2004). Growth and characterization of Nd-doped SBN single crystal fibers. Applied Physics A, 78(7), 1037-1042. doi:10.1007/s00339-003-2151-3Chayapiwut, N., Honma, T., Benino, Y., Fujiwara, T., & Komatsu, T. (2005). Synthesis of Sm3+-doped strontium barium niobate crystals in glass by samarium atom heat processing. Journal of Solid State Chemistry, 178(11), 3507-3513. doi:10.1016/j.jssc.2005.09.002Haro-González, P., Martín, I. R., Martín, L. L., León-Luis, S. F., Pérez-Rodríguez, C., & Lavín, V. (2011). Characterization of Er3+ and Nd3+ doped Strontium Barium Niobate glass ceramic as temperature sensors. Optical Materials, 33(5), 742-745. doi:10.1016/j.optmat.2010.11.026Ivleva, L. I., Volk, T. R., Isakov, D. V., Gladkii, V. V., Polozkov, N. M., & Lykov, P. A. (2002). Growth and ferroelectric properties of Nd-doped strontium–barium niobate crystals. Journal of Crystal Growth, 237-239, 700-702. doi:10.1016/s0022-0248(01)01997-2Marcinkevičius, A., Juodkazis, S., Watanabe, M., Miwa, M., Matsuo, S., Misawa, H., & Nishii, J. (2001). Femtosecond laser-assisted three-dimensional microfabrication in silica. Optics Letters, 26(5), 277. doi:10.1364/ol.26.000277Sato, R., Benino, Y., Fujiwara, T., & Komatsu, T. (2001). YAG laser-induced crystalline dot patterning in samarium tellurite glasses. Journal of Non-Crystalline Solids, 289(1-3), 228-232. doi:10.1016/s0022-3093(01)00736-0Haro-González, P., Martín, L. L., González-Pérez, S., & Martín, I. R. (2010). Formation of Nd3+ doped Strontium Barium Niobate nanocrystals by two different methods. Optical Materials, 32(10), 1389-1392. doi:10.1016/j.optmat.2010.03.011Haro-González, P., Martín, I. R., & Creus, A. H. (2010). Nanocrystals distribution inside the writing lines in a glass matrix using Argon laser irradiation. Optics Express, 18(2), 582. doi:10.1364/oe.18.000582Haro-González, P., Martín, I. R., Arbelo-Jorge, E., González-Pérez, S., Cáceres, J. M., & Núñez, P. (2008). Laser irradiation in Nd3+ doped strontium barium niobate glass. Journal of Applied Physics, 104(1), 013112. doi:10.1063/1.2952011Kowalska, D., Haro-González, P., Martín, I. R., & Cáceres, J. M. (2010). Analysis of the optical properties of Er3+-doped strontium barium niobate nanocrystals using time-resolved laser spectroscopy. Applied Physics A, 99(4), 771-776. doi:10.1007/s00339-010-5716-yPellicer-Porres, J., Segura, A., Martínez-Criado, G., Rodríguez-Mendoza, U. R., & Lavín, V. (2012). Formation of nanostructures in Eu3+doped glass–ceramics: an XAS study. Journal of Physics: Condensed Matter, 25(2), 025303. doi:10.1088/0953-8984/25/2/025303Martínez-Criado, G., Alén, B., Sans, J. A., Homs, A., Kieffer, I., Tucoulou, R., … Yi, G. (2012). Spatially resolved X-ray excited optical luminescence. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 284, 36-39. doi:10.1016/j.nimb.2011.08.013Martínez-Criado, G., Sans, J. A., Segura-Ruiz, J., Tucoulou, R., Solé, A. V., Homs, A., … Alén, B. (2011). X-ray excited optical luminescence imaging of InGaN nano-LEDs. physica status solidi (c), 9(3-4), 628-630. doi:10.1002/pssc.201100430Villanova, J., Segura-Ruiz, J., Lafford, T., & Martinez-Criado, G. (2012). Synchrotron microanalysis techniques applied to potential photovoltaic materials. Journal of Synchrotron Radiation, 19(4), 521-524. doi:10.1107/s0909049512021383Smith, J., Akbari-Sharbaf, A., Ward, M. J., Murphy, M. W., Fanchini, G., & Kong Sham, T. (2013). Luminescence properties of defects in nanocrystalline ZnO. Journal of Applied Physics, 113(9), 093104. doi:10.1063/1.4794001Armelao, L., Heigl, F., Jürgensen, A., Blyth, R. I. R., Regier, T., Zhou, X.-T., & Sham, T. K. (2007). X-ray Excited Optical Luminescence Studies of ZnO and Eu-Doped ZnO Nanostructures. The Journal of Physical Chemistry C, 111(28), 10194-10200. doi:10.1021/jp071379fMartínez-Criado, G., Villanova, J., Tucoulou, R., Salomon, D., Suuronen, J.-P., Labouré, S., … Morse, J. (2016). ID16B: a hard X-ray nanoprobe beamline at the ESRF for nano-analysis. Journal of Synchrotron Radiation, 23(1), 344-352. doi:10.1107/s1600577515019839Jamieson, P. B., Abrahams, S. C., & Bernstein, J. L. (1968). Ferroelectric Tungsten Bronze‐Type Crystal Structures. I. Barium Strontium Niobate Ba0.27Sr0.75Nb2O5.78. The Journal of Chemical Physics, 48(11), 5048-5057. doi:10.1063/1.1668176Haro-González, P., Martín, I. R., & Hernández Creus, A. (2011). Nanocrystals formation on Ho3+ doped strontium barium niobate glass. Journal of Luminescence, 131(4), 657-661. doi:10.1016/j.jlumin.2010.11.011Lavı́n, V., Rodrı́guez-Mendoza, U. R., Martı́n, I. R., & Rodrı́guez, V. D. (2003). Optical spectroscopy analysis of the Eu3+ ions local structure in calcium diborate glasses. Journal of Non-Crystalline Solids, 319(1-2), 200-216. doi:10.1016/s0022-3093(02)01914-2Chernaya, T. S., Volk, T. R., Verin, I. A., Ivleva, L. I., & Simonov, V. I. (2002). Atomic structure of (Sr0.50Ba0.50)Nb2O6 single crystals in the series of (SrxBa1 − x )Nb2O6 compounds. Crystallography Reports, 47(2), 213-216. doi:10.1134/1.1466494Erbil, A., Cargill III, G. S., Frahm, R., & Boehme, R. F. (1988). Total-electron-yield current measurements for near-surface extended x-ray-absorption fine structure. Physical Review B, 37(5), 2450-2464. doi:10.1103/physrevb.37.2450Solé, V. A., Papillon, E., Cotte, M., Walter, P., & Susini, J. (2007). A multiplatform code for the analysis of energy-dispersive X-ray fluorescence spectra. Spectrochimica Acta Part B: Atomic Spectroscopy, 62(1), 63-68. doi:10.1016/j.sab.2006.12.002Martínez-Criado, G., Homs, A., Alén, B., Sans, J. A., Segura-Ruiz, J., Molina-Sánchez, A., … Yi, G.-C. (2012). Probing Quantum Confinement within Single Core–Multishell Nanowires. Nano Letters, 12(11), 5829-5834. doi:10.1021/nl303178uMartínez-Criado, G., Segura-Ruiz, J., Alén, B., Eymery, J., Rogalev, A., Tucoulou, R., & Homs, A. (2014). Exploring Single Semiconductor Nanowires with a Multimodal Hard X-ray Nanoprobe. Advanced Materials, 26(46), 7873-7879. doi:10.1002/adma.201304345Shyu, J.-J., & Wang, J.-R. (2000). Crystallization and Dielectric Properties of SrO-BaO-Nb2O5-SiO2Tungsten-Bronze Glass-Ceramics. Journal of the American Ceramic Society, 83(12), 3135-3140. doi:10.1111/j.1151-2916.2000.tb01694.

The LSD1 inhibitor iadademstat (ORY-1001) targets SOX2-driven breast cancer stem cells: a potential epigenetic therapy in luminal-B and HER2-positive breast cancer subtypes

SOX2 is a core pluripotency-associated transcription factor causally related to cancer initiation, aggressiveness, and drug resistance by driving the self-renewal and seeding capacity of cancer stem cells (CSC). Here, we tested the ability of the clinically proven inhibitor of the lysine-specific demethylase 1 (LSD1/KDM1A) iadademstat (ORY-100) to target SOX2-driven CSC in breast cancer. Iadademstat blocked CSC-driven mammosphere formation in breast cancer cell lines that are dependent on SOX2 expression to maintain their CSC phenotype. Iadademstat prevented the activation of an LSD1-targeted stemness-specific SOX2 enhancer in CSC-enriched 3-dimensional spheroids. Using high-throughput transcriptional data available from the METABRIC dataset, high expression of SOX2 was significantly more common in luminal-B and HER2-enriched subtypes according to PAM50 classifier and in IntClust1 (high proliferating luminal-B) and IntClust 5 (luminal-B and HER2-amplified) according to integrative clustering. Iadademstat significantly reduced mammospheres formation by CSC-like cells from a multidrug-resistant luminal-B breast cancer patient-derived xenograft but not of those from a treatment-naive luminal-A patient. Iadademstat reduced the expression of SOX2 in luminal-B but not in luminal-A mammospheres, likely indicating a selective targeting of SOX2-driven CSC. The therapeutic relevance of targeting SOX2-driven breast CSC suggests the potential clinical use of iadademstat as an epigenetic therapy in luminal-B and HER2-positive subtypes

Aeolian transport of viable microbial life across the Atacama Desert, Chile : Implications for Mars

A.A.B. and A.G.F. thank the Project “icyMARS”, funded by the European Research Council, ERC Starting Grant No. 307496. M.P.Z., C.G.S., R.F. and F.J.M.T. thank the funding received from the Dubai Future Foundation through the Guaana.com open research platform (https://www.guaana.com/projects/jeGEimuX6DLCLsbQP).Peer reviewedPublisher PD

A micellar formulation of quercetin prevents cisplatin nephrotoxicity

Producción CientíficaThe antioxidant flavonoid quercetin has been shown to prevent nephrotoxicity in animal models and in a clinical study and is thus a very promising prophylactic candidate under development. Quercetin solubility is very low, which handicaps clinical application. The aim of this work was to study, in rats, the bioavailability and nephroprotective efficacy of a micellar formulation of Pluronic F127-encapsulated quercetin (P-quercetin), with improved hydrosolubility. Intraperitoneal administration of P-quercetin leads to an increased plasma concentration and bioavailability of quercetin compared to the equimolar administration of natural quercetin. Moreover, P-quercetin retains overall nephroprotective properties, and even slightly improves some renal function parameters, when compared to natural quercetin. Specifically, P-quercetin reduced the increment in plasma creatinine (from 3.4 ± 0.5 to 1.2 ± 0.3 mg/dL) and urea (from 490.9 ± 43.8 to 184.1 ± 50.1 mg/dL) and the decrease in creatinine clearance (from 0.08 ± 0.02 to 0.58 ± 0.19 mL/min) induced by the nephrotoxic chemotherapeutic drug cisplatin, and it ameliorated histological evidence of tubular damage. This new formulation with enhanced kinetic and biopharmaceutical properties will allow for further exploration of quercetin as a candidate nephroprotector at lower dosages and by administration routes oriented towards its clinical use.Fundación de Universidades y Enseñanzas Superiores de Castilla y León (FUESCyL) y Banco de Santander - (grant: Ed. 2014– 2015 Desafío UNIV-EMP)Fundación General de la Universidad de Salamanca, Fondo Europeo de Desarrollo Regional (FEDER) y Junta de Castilla y León - (grant: Ed. 2015 Lanzadera TC)Junta de Castilla y León - (grant: VA225U14

Extra Virgin Olive Oil Contains a Phenolic Inhibitor of the Histone Demethylase LSD1/KDM1A

The lysine-specific histone demethylase 1A (LSD1) also known as lysine (K)-specific demethylase 1A (KDM1A) is a central epigenetic regulator of metabolic reprogramming in obesity-associated diseases, neurological disorders, and cancer. Here, we evaluated the ability of oleacein, a biophenol secoiridoid naturally present in extra virgin olive oil (EVOO), to target LSD1. Molecular docking and dynamic simulation approaches revealed that oleacein could target the binding site of the LSD1 cofactor flavin adenosine dinucleotide with high affinity and at low concentrations. At higher concentrations, oleacein was predicted to target the interaction of LSD1 with histone H3 and the LSD1 co-repressor (RCOR1/CoREST), likely disturbing the anchorage of LSD1 to chromatin. AlphaScreen-based in vitro assays confirmed the ability of oleacein to act as a direct inhibitor of recombinant LSD1, with an IC50 as low as 2.5 umol/L. Further, oleacein fully suppressed the expression of the transcription factor SOX2 (SEX determining Region Y-box 2) in cancer stem-like and induced pluripotent stem (iPS) cells, which specifically occurs under the control of an LSD1-targeted distal enhancer. Conversely, oleacein failed to modify ectopic SOX2 overexpression driven by a constitutive promoter. Overall, our findings provide the first evidence that EVOO contains a naturally occurring phenolic inhibitor of LSD1, and support the use of oleacein as a template to design new secoiridoid-based LSD1 inhibitors.Work in the Menendez laboratory is supported by the Spanish Ministry of Science and Innovation (Grant SAF2016-80639-P, Plan Nacional de l+D+I, founded by the European Regional Development Fund, Spain) and by an unrestricted research grant from the Fundació Oncolliga Girona (Lliga catalana d’ajuda al malalt de càncer, Girona). The Spanish Ministry of Economy and Competitiveness (MINECO, Project RTI2018-096724-B-C21) and the Generalitat Valenciana (PROMETEO/2016/006) supports work in the Encinar laborator

Mitochondrial echoes of first settlement and genetic continuity in El Salvador

Background: From Paleo-Indian times to recent historical episodes, the Mesoamerican isthmus played an important role in the distribution and patterns of variability all around the double American continent. However, the amount of genetic information currently available on Central American continental populations is very scarce. In order to shed light on the role of Mesoamerica in the peopling of the New World, the present study focuses on the analysis of the mtDNA variation in a population sample from El Salvador. Methodology/Principal Findings: We have carried out DNA sequencing of the entire control region of the mitochondrial DNA (mtDNA) genome in 90 individuals from El Salvador. We have also compiled more than 3,985 control region profiles from the public domain and the literature in order to carry out inter-population comparisons. The results reveal a predominant Native American component in this region: by far, the most prevalent mtDNA haplogroup in this country (at ~90%) is A2, in contrast with other North, Meso- and South American populations. Haplogroup A2 shows a star-like phylogeny and is very diverse with a substantial proportion of mtDNAs (45%; sequence range 16090–16365) still unobserved in other American populations. Two different Bayesian approaches used to estimate admixture proportions in El Salvador shows that the majority of the mtDNAs observed come from North America. A preliminary founder analysis indicates that the settlement of El Salvador occurred about 13,400±5,200 Y.B.P.. The founder age of A2 in El Salvador is close to the overall age of A2 in America, which suggests that the colonization of this region occurred within a few thousand years of the initial expansion into the Americas. Conclusions/Significance: As a whole, the results are compatible with the hypothesis that today's A2 variability in El Salvador represents to a large extent the indigenous component of the region. Concordant with this hypothesis is also the observation of a very limited contribution from European and African women (~5%). This implies that the Atlantic slave trade had a very small demographic impact in El Salvador in contrast to its transformation of the gene pool in neighbouring populations from the Caribbean facade

A genome-wide association study follow-up suggests a possible role for PPARG in systemic sclerosis susceptibility

Introduction: A recent genome-wide association study (GWAS) comprising a French cohort of systemic sclerosis (SSc) reported several non-HLA single-nucleotide polymorphisms (SNPs) showing a nominal association in the discovery phase. We aimed to identify previously overlooked susceptibility variants by using a follow-up strategy.<p></p> Methods: Sixty-six non-HLA SNPs showing a P value <10-4 in the discovery phase of the French SSc GWAS were analyzed in the first step of this study, performing a meta-analysis that combined data from the two published SSc GWASs. A total of 2,921 SSc patients and 6,963 healthy controls were included in this first phase. Two SNPs, PPARG rs310746 and CHRNA9 rs6832151, were selected for genotyping in the replication cohort (1,068 SSc patients and 6,762 healthy controls) based on the results of the first step. Genotyping was performed by using TaqMan SNP genotyping assays. Results: We observed nominal associations for both PPARG rs310746 (PMH = 1.90 × 10-6, OR, 1.28) and CHRNA9 rs6832151 (PMH = 4.30 × 10-6, OR, 1.17) genetic variants with SSc in the first step of our study. In the replication phase, we observed a trend of association for PPARG rs310746 (P value = 0.066; OR, 1.17). The combined overall Mantel-Haenszel meta-analysis of all the cohorts included in the present study revealed that PPARG rs310746 remained associated with SSc with a nominal non-genome-wide significant P value (PMH = 5.00 × 10-7; OR, 1.25). No evidence of association was observed for CHRNA9 rs6832151 either in the replication phase or in the overall pooled analysis.<p></p> Conclusion: Our results suggest a role of PPARG gene in the development of SSc

LMO2 expression reflects the different stages of blast maturation and genetic features in B-cell acute lymphoblastic leukemia and predicts clinical outcome

BACKGROUND: LMO2 is highly expressed at the most immature stages of lymphopoiesis. In T-lymphocytes, aberrant LMO2 expression beyond those stages leads to T-cell acute lymphoblastic leukemia, while in B cells LMO2 is also expressed in germinal center lymphocytes and diffuse large B-cell lymphomas, where it predicts better clinical outcome. The implication of LMO2 in B-cell acute lymphoblastic leukemia must still be explored. DESIGN AND METHODS: We measured LMO2 expression by real time RT-PCR in 247 acute lymphoblastic leukemia patient samples with cytogenetic data (144 of them also with survival and immunophenotypical data) and in normal hematopoietic and lymphoid cells. RESULTS: B-cell acute lymphoblastic leukemia cases expressed variable levels of LMO2 depending on immunophenotypical and cytogenetic features. Thus, the most immature subtype, pro-B cells, displayed three-fold higher LMO2 expression than pre-B cells, common-CD10+ or mature subtypes. Additionally, cases with TEL-AML1 or MLL rearrangements exhibited two-fold higher LMO2 expression compared to cases with BCR-ABL rearrangements or hyperdyploid karyotype. Clinically, high LMO2 expression correlated with better overall survival in adult patients (5-year survival rate 64.8% (42.5%-87.1%) vs. 25.8% (10.9%-40.7%), P= 0.001) and constituted a favorable independent prognostic factor in B-ALL with normal karyotype: 5-year survival rate 80.3% (66.4%-94.2%) vs. 63.0% (46.1%-79.9%) (P= 0.043). CONCLUSIONS: Our data indicate that LMO2 expression depends on the molecular features and the differentiation stage of B-cell acute lymphoblastic leukemia cells. Furthermore, assessment of LMO2 expression in adult patients with a normal karyotype, a group which lacks molecular prognostic factors, could be of clinical relevance

Deep Investigation of Neutral Gas Origins (DINGO): HI stacking experiments with early science data

We present early science results from Deep Investigation of Neutral Gas Origins (DINGO), an HI survey using the Australian Square Kilometre Array Pathfinder (ASKAP). Using ASKAP sub-arrays available during its commissioning phase, DINGO early science data were taken over $\sim$ 60 deg$^{2}$ of the Galaxy And Mass Assembly (GAMA) 23 h region with 35.5 hr integration time. We make direct detections of six known and one new sources at $z < 0.01$. Using HI spectral stacking, we investigate the HI gas content of galaxies at $0.04 < z< 0.09$ for different galaxy colours. The results show that galaxy morphology based on optical colour is strongly linked to HI gas properties. To examine environmental impacts on the HI gas content of galaxies, three sub-samples are made based on the GAMA group catalogue. The average HI mass of group central galaxies is larger than those of satellite and isolated galaxies, but with a lower HI gas fraction. We derive a variety of HI scaling relations for physical properties of our sample, including stellar mass, stellar mass surface density, $NUV-r$ colour, specific star formation rate, and halo mass. We find that the derived HI scaling relations are comparable to other published results, with consistent trends also observed to $\sim$0.5 dex lower limits in stellar mass and stellar surface density. The cosmic HI densities derived from our data are consistent with other published values at similar redshifts. DINGO early science highlights the power of HI spectral stacking techniques with ASKAP.Comment: 27 pages, 25 figures, 10 tables, accepted for publication in MNRA