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Is nitric oxide the forgotten nephroprotective treatment during cardiac surgery?
Entanglement of quantum spin systems: a valence-bond approach
In order to quantify entanglement between two parts of a quantum system, one
of the most used estimator is the Von Neumann entropy. Unfortunately, computing
this quantity for large interacting quantum spin systems remains an open issue.
Faced with this difficulty, other estimators have been proposed to measure
entanglement efficiently, mostly by using simulations in the valence-bond
basis. We review the different proposals and try to clarify the connections
between their geometric definitions and proper observables. We illustrate this
analysis with new results of entanglement properties of spin 1 chains.Comment: Proceedings of StatPhys 24 satellite conference in Hanoi; submitted
for a special issue of Modern Physics Letters
Valence bond entanglement entropy of frustrated spin chains
We extend the definition of the recently introduced valence bond entanglement
entropy to arbitrary SU(2) wave functions of S=1/2 spin systems. Thanks to a
reformulation of this entanglement measure in terms of a projection, we are
able to compute it with various numerical techniques for frustrated spin
models. We provide extensive numerical data for the one-dimensional J1-J2 spin
chain where we are able to locate the quantum phase transition by using the
scaling of this entropy with the block size. We also systematically compare
with the scaling of the von Neumann entanglement entropy. We finally underline
that the valence-bond entropy definition does depend on the choice of
bipartition so that, for frustrated models, a "good" bipartition should be
chosen, for instance according to the Marshall sign.Comment: 10 pages, 6 figures; v2: published versio
GreenPhylDB: A Gene Family Database for plant functional Genomics
With the increasing number of genomes being sequenced, a major objective is to transfer accurate annotation from characterised proteins to uncharacterised sequences. Consequently, comparative genomics has become a usual and efficient strategy in functional genomics. The release of various annotated genomes of plants, such as _O. sativa_ and _A. thaliana_, has allowed setting up comprehensive lists of gene families defined by automated methods. However, like for gene sequence, manual curation of gene families is an important requirement that has to be undertaken. GreenPhylDB comprises protein sequences of 12 plant species fully sequenced that were grouped into homeomorphic families using similarity-based methods. Clusters are finally processed by phylogenetic analysis to infer orthologs and paralogs that will be particularly helpful to study genome evolution. Previously, each cluster has to be curated (i.e. properly named and classified) using different sources of information. A web interface for plant gene families’ curation was developed for that purpose. This interface, accessible on GreenPhylDB ("http://greenphyl.cirad.fr":http://greenphyl.cirad.fr), centralizes external references (e.g. InterPro, KEGG, Swiss-Prot, PIRSF, Pubmed) related to all gene members of the clusters and shows statistics and automatic analysis. We believe that this synthetic view of data available for a gene cluster, combined with basic guidelines, is an efficient way to provide reliable method for gene family annotations
From Marvel to Science Fiction Intellectual and Literary History of Insects.
M.A. Thesis. University of HawaiÊ»i at MÄnoa 2018
Induced folding in RNA recognition by Arabidopsis thaliana DCL1
DCL1 is the ribonuclease that carries out miRNA biogenesis in plants. The enzyme has two tandem double stranded RNA binding domains (dsRBDs) in its C-terminus. Here we show that the first of these domains binds precursor RNA fragments when isolated and cooperates with the second domain in the recognition of substrate RNA. Remarkably, despite showing RNA binding activity, this domain is intrinsically disordered. We found that it acquires a folded conformation when bound to its substrate, being the first report of a complete dsRBD folding upon binding. The free unfolded form shows tendency to adopt folded conformations, and goes through an unfolded bound state prior to the folding event. The significance of these results is discussed by comparison with the behavior of other dsRBDs.Fil: Suarez, Irina Paula. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Rosario. Instituto de BiologĂa Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂmicas y FarmacĂ©uticas. Instituto de BiologĂa Molecular y Celular de Rosario; ArgentinaFil: Burdisso, Paula. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Rosario. Instituto de BiologĂa Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂmicas y FarmacĂ©uticas. Instituto de BiologĂa Molecular y Celular de Rosario; ArgentinaFil: Benoit Matthieu P. M. H.. Institut de Biologie Structurale Jean Pierre Ebel; FranciaFil: Boisbouvier, Jerome. Institut de Biologie Structurale Jean Pierre Ebel; FranciaFil: Rasia, Rodolfo Maximiliano. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Rosario. Instituto de BiologĂa Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂmicas y FarmacĂ©uticas. Instituto de BiologĂa Molecular y Celular de Rosario; Argentin
Two-loop Functional Renormalization Group of the Random Field and Random Anisotropy O(N) Models
We study by the perturbative Functional Renormalization Group (FRG) the
Random Field and Random Anisotropy O(N) models near , the lower critical
dimension of ferromagnetism. The long-distance physics is controlled by
zero-temperature fixed points at which the renormalized effective action is
nonanalytic. We obtain the beta functions at 2-loop order, showing that despite
the nonanalytic character of the renormalized effective action, the theory is
perturbatively renormalizable at this order. The physical results obtained at
2-loop level, most notably concerning the breakdown of dimensional reduction at
the critical point and the stability of quasi-long range order in , are
shown to fit into the picture predicted by our recent non-perturbative FRG
approach.Comment: 19 pages, 20 figures. Minor correction
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