Numerical investigation of gapped edge states in fractional quantum Hall-superconductor heterostructures

Fractional quantum Hall-superconductor heterostructures may provide a platform towards non-abelian topological modes beyond Majoranas. However their quantitative theoretical study remains extremely challenging. We propose and implement a numerical setup for studying edge states of fractional quantum Hall droplets with a superconducting instability. The fully gapped edges carry a topological degree of freedom that can encode quantum information protected against local perturbations. We simulate such a system numerically using exact diagonalization by restricting the calculation to the quasihole-subspace of a (time-reversal symmetric) bilayer fractional quantum Hall system of Laughlin $\nu=1/3$ states. We show that the edge ground states are permuted by spin-dependent flux insertion and demonstrate their fractional $6\pi$ Josephson effect, evidencing their topological nature and the Cooper pairing of fractionalized quasiparticles.Comment: 12 pages, 9 figure

Bioprotección de los cultivos tropicales en Martinica: experiencias y perspectivas con RIS en la piña y el banano

Los parásitos del suelo que afectan el cultivo de la piña (Rotylenchulus reniformis y sínfilos) y de banano (Pratylenchus coffeae) no pueden ser controlados con pesticidas en Martinica según la nueva normativa europea. Por lo tanto, buscamos una posible alternativa utilizando resistencias sistémicas (RSI) como parte de agrosistemas más ecológicos. En el Campus Agro-ambiental del Carïbe desarrollamos una estrategia basada en la utilización de plantas de cobertura (rotación/asociación) para reducir el inóculo de parásitos e inducir algunas defensas naturales que permitieran mantener el bajo nivel de estos parásitos durante el crecimiento de los cultivos. Estas defensas son las resistencias sistémicas inducidas (RSI) que pueden resultar de la interacción entre plantas y microorganismos beneficiosos. Estas investigaciones se basaron en cuatro hipótesis principales: 1) Es posible reducir el inóculo de parásitos del suelo por la introducción de plantas de rotación no hospedantes de las plagas en sistemas de cultivo sin pesticidas. Para ello se emplearon plantas de cobertura que fueron seleccionadas sobre la base de varias características funcionales (plantas no-hospedantes de las plagas, con una mayor biomasa, que pueden contribuir al equilibrio de los microorganismos en la rizosfera y en particular aumentar el potencial de micorrización del suelo. 2) Se puede identificar y seleccionar variedades de piña y banano con habilidad para desarrollar RSI y adaptar su metabolismo a cambios ambientales. Para lograr este objetivo se determinó la respuesta diferencial de las plantas frente a los nemátodos mediante la evaluación de un inductor de RSI (Metiljasmonato, 10-4M) en varias variedades de piña y de banano. Se analiza la adaptabilidad de estas plantas a los cambios ambientales a través de marcadores moleculares (genes de cisteíno-proteasa y su inhibidor natural, una fito-cistatina). 3) Los estreses abióticos (sequía, temperatura, salinidad, etc) podrían tener un impacto significativo sobre la eficiencia de las RSI. Las RSI también pueden contribuir a la capacidad de adaptación de las plantas a los estreses medioambientales, se estudia la posible relación entre el nivel de estrés de las plantas y su capacidad para inducir RSI contra los parásitos del suelo. 4) Se pueden aislar bacterias diazotróficas y endofíticas de las raíces de piña y banano inductoras de RSI en el campo. Se aislaron más de 30 cepas bacterianas diazotróficas (endofíticas) de muestras de raíces de cultivos de piña y banano de diferentes áreas de referencia en Martinica. Actualmente se está procesando la identificación de las bacterias (MIDI-FAME y por secuenciación ADNr16S) y se seleccionarán las bacterias más promisorias como inductoras de RSI. Nuestras investigaciónes tienden a validar la hipótesis que la sostenibilidad de la eficiencia de las RSI a los patógenos del suelo depende de la selección de variedades específicas producidas en condiciones agro-ambientales adecuadas para la expresión de las defensas naturales

First events from the CNGS neutrino beam detected in the OPERA experiment

The OPERA neutrino detector at the underground Gran Sasso Laboratory (LNGS) was designed to perform the first detection of neutrino oscillations in appearance mode, through the study of nu_mu to nu_tau oscillations. The apparatus consists of a lead/emulsion-film target complemented by electronic detectors. It is placed in the high-energy, long-baseline CERN to LNGS beam (CNGS) 730 km away from the neutrino source. In August 2006 a first run with CNGS neutrinos was successfully conducted. A first sample of neutrino events was collected, statistically consistent with the integrated beam intensity. After a brief description of the beam and of the various sub-detectors, we report on the achievement of this milestone, presenting the first data and some analysis results.Comment: Submitted to the New Journal of Physic

Novel applications of long-established histochemical techniques to study nanoparticle-cell interactions at transmission electron microscopy

Alcian blue staining has been used to visualise nanoparticles at transmission electron microscop

Hyaluronic acid-based nanocomplexes as novel drug-nanocarriers to treat myotonic dystrophy

Hyaluronic acid-based nanocomplexes have been developpend as novel drug-nanocarriers to treat myotonic dystroph

Lymphoid Hyperplasia and Lymphoma in Transgenic Mice Expressing the Small Non-Coding RNA, EBER1 of Epstein-Barr Virus

Non-coding RNAs have critical functions in diverse biological processes, particularly in gene regulation. Viruses, like their host cells, employ such functional RNAs and the human cancer associated Epstein-Barr virus (EBV) is no exception. Nearly all EBV associated tumours express the EBV small, non-coding RNAs (EBERs) 1 and 2, however their role in viral pathogenesis remains largely obscure.To investigate the action of EBER1 in vivo, we produced ten transgenic mouse lines expressing EBER1 in the lymphoid compartment using the mouse immunoglobulin heavy chain intronic enhancer Emicro. Mice of several of these EmicroEBER1 lines developed lymphoid hyperplasia which in some cases proceeded to B cell malignancy. The hallmark of the transgenic phenotype is enlargement of the spleen and mesenteric lymph nodes and in some cases enlargement of the thymus, liver and peripheral lymph nodes. The tumours were found to be of B cell origin and showed clonal IgH rearrangements. In order to explore if EBER1 would cooperate with c-Myc (deregulated in Burkitt's lymphoma) to accelerate lymphomagenesis, a cross-breeding study was undertaken with EmicroEBER1 and EmicroMyc mice. While no significant reduction in latency to lymphoma onset was observed in bi-transgenic mice, c-Myc induction was detected in some EmuEBER1 single transgenic tumours, indicative of a functional cooperation.This study is the first to describe the in vivo expression of a polymerase III, non-coding viral gene and demonstrate its oncogenic potential. The data suggest that EBER1 plays an oncogenic role in EBV associated malignant disease

Dynamics and level statistics of interacting fermions in the lowest Landau level

We consider the unitary dynamics of interacting fermions in the lowest Landau level, on spherical and toroidal geometries. The dynamics are driven by the interaction Hamiltonian which, viewed in the basis of single-particle Landau orbitals, contains correlated pair hopping terms in addition to static repulsion. This setting and this type of Hamiltonian has a significant history in numerical studies of fractional quantum Hall (FQH) physics, but the many-body quantum dynamics generated by such correlated hopping has not been explored in detail. We focus on initial states containing all the fermions in one block of orbitals. We characterize in detail how the fermionic liquid spreads out starting from such a state. We identify and explain differences with regular (single-particle) hopping Hamiltonians. Such differences are seen, e.g. in the entanglement dynamics, in that some initial block states are frozen or near-frozen, and in density gradients persisting in long-time equilibrated states. Examining the level spacing statistics, we show that the most common Hamiltonians used in FQH physics are not integrable, and explain that GOE statistics (level statistics corresponding to the Gaussian orthogonal ensemble) can appear in many cases despite the lack of time-reversal symmetry

Tackling TNF-α in autoinflammatory disorders and autoimmune diseases: From conventional to cutting edge in biologics and RNA- based nanomedicines

Autoinflammatory disorders and autoimmune diseases result from abnormal deviations of innate and adaptive immunity that heterogeneously affect organs and clinical phenotypes. Despite having etiologic and phenotypic differences, these two conditions share the onset of an aberrant inflammatory process. Targeting the main drivers controlling inflammation is useful to treat both autoimmune and autoinflammatory syndromes. TNF-alpha is a major player in the inflammatory immune response, and anti-TNF-alpha antibodies have been a revolutionary treatment in many autoimmune disorders. However, production difficulties and high development costs hinder their imple-mentation, and accessibility to their use is still limited. Innovative strategies aimed at overcoming the limitations associated with anti-TNF-alpha antibodies are being explored, including RNA-based therapies.Here we summarize the central role of TNF-alpha in immune disorders and how anti-TNF-based immunotherapies changed the therapeutic landscape, albeit with important limitations related to side effects, tolerance, and resistance to therapies. We then outline how nanotechnology has provided the final momentum for the use of nucleic acids in the treatment of autoimmune and autoinflammatory diseases, with a focus on inflammatory bowel diseases (IBDs). The example of IBDs allows the evaluation and discussion of the nucleic acids-based treatments that have been developed, to identify the role that innovative approaches possess in view of the treatment of autoinflammatory disorders and autoimmune diseases

Nanocarriers for neuromuscular diseases

Overview of the results obtained so far in the frame of a research on suitable nanocarriers for treating myotonic dystroph

Diamond Blackfan anemia is mediated by hyperactive Nemo-like kinase

Diamond Blackfan Anemia (DBA) is a congenital bone marrow failure syndrome associated with ribosomal gene mutations that lead to ribosomal insufficiency. DBA is characterized by anemia, congenital anomalies, and cancer predisposition. Treatment for DBA is associated with significant morbidity. Here, we report the identification of Nemo-like kinase (NLK) as a potential target for DBA therapy. To identify new DBA targets, we screen for small molecules that increase erythroid expansion in mouse models of DBA. This screen identified a compound that inhibits NLK. Chemical and genetic inhibition of NLK increases erythroid expansion in mouse and human progenitors, including bone marrow cells from DBA patients. In DBA models and patient samples, aberrant NLK activation is initiated at the Megakaryocyte/Erythroid Progenitor (MEP) stage of differentiation and is not observed in non-erythroid hematopoietic lineages or healthy erythroblasts. We propose that NLK mediates aberrant erythropoiesis in DBA and is a potential target for therapy