964 research outputs found

    Exploiting quantum parallelism of entanglement for a complete experimental quantum characterization of a single qubit device

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    We present the first full experimental quantum tomographic characterization of a single-qubit device achieved with a single entangled input state. The entangled input state plays the role of all possible input states in quantum parallel on the tested device. The method can be trivially extended to any n-qubits device by just replicating the whole experimental setup n times.Comment: 4 pages in revtex4 with 4 eps figure

    Effects of lithiation on the fracture toughness and mechanical properties of LiMn2O4 cathode battery materials

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    The micro-pillar splitting method has been used to assess the influence of lithiation on the fracture toughness of LixMn2O4 micro-particles used as cathode materials in lithium ion battery composites. The materials under investigation consisted of hard LiMn2O4 particles embedded in a soft and compliant epoxy matrix to form the composite electrode. Five different samples were extracted from commercial battery cells at different states of charge (SoC% = 0-20-50-75-100%). These correspond to different lithium concentrations in the particles, as measured by inductively coupled plasma optical emission spectrometry (ICP-OES). Experimental results from the pillar splitting experiments show a significant effect of the SoC%, and therefore the lithiation level, on the fracture toughness and failure mechanisms of the LixMn2O4 particles. Specifically, the toughness of the fully charged electrodes (de-lithiated material) is much lower that the fully discharged electrodes. SEM observation of split pillars (see figure) confirms a significant change in toughness of the materials as a function of the lithium concentration in the particles. The results compare well with recent investigations where a loss in ductility of electrode materials has been observed after de-lithiation. This suggests that a knowledge of the changes in toughness of the materials may be extremely important for prediction of in-service damage of the electrodes due to diffusion-induced stress during charge/discharge cycles. An analysis of pillar splitting for a hard film on a compliant substrate material shows that the critical load for splitting is relatively insensitive to the substrate compliance for a large range of material properties. This ensures a correct estimation of the critical splitting load in the case of the composite materials studied in this investigatio

    Hartree-Fock-Bogoliubov theory versus local-density approximation for superfluid trapped fermionic atoms

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    We investigate a gas of superfluid fermionic atoms trapped in two hyperfine states by a spherical harmonic potential. We propose a new regularization method to remove the ultraviolet divergence in the Hartree-Fock-Bogoliubov equations caused by the use of a zero-range atom-atom interaction. Compared with a method used in the literature, our method is simpler and has improved convergence properties. Then we compare Hartree-Fock-Bogoliubov calculations with the semiclassical local-density approximation. We observe that for systems containing a small number of atoms shell effects, which cannot be reproduced by the semiclassical calculation, are very important. For systems with a large number of atoms at zero temperature the two calculations are in quite good agreement, which, however, is deteriorated at non-zero temperature, especially near the critical temperature. In this case the different behavior can be explained within the Ginzburg-Landau theory.Comment: 12 pages, 8 figures, revtex; v2: references and clarifying remarks adde

    Towards the Thermodynamics of Localization Processes

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    We study the entropy time evolution of a quantum mechanical model, which is frequently used as a prototype for Anderson's localization. Recently Latora and Baranger [V. Latora, M. Baranger, Phys. Rev.Lett. 82, 520(1999)] found that there exist three entropy regimes, a transient regime of passage from dynamics to thermodynamics, a linear in time regime of entropy increase, namely a thermodynamic regime of Kolmogorov kind, and a saturation regime. We use the non-extensive entropic indicator recently advocated by Tsallis [ C. Tsallis, J. Stat. Phys. 52, 479 (1988)] with a mobile entropic index q, and we find that with the adoption of the ``magic'' value q = Q = 1/2 the Kolmogorov regime becomes more extended and more distinct than with the traditional entropic index q = 1. We adopt a two-site model to explain these properties by means of an analytical treatment and we argue that Q =1/2 might be a typical signature of the occurrence of Anderson's localization.Comment: 13 pages, 8 figures submitted to Phys. Rev.

    Buenas prácticas en la declaración de obras huérfanas en Europa

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    Se presenta un análisis de los proyectos europeos de preservación y digitalización del patrimonio cultural que, como ejemplo de buenas prácticas, han sido origen de la declaración de obras huérfanas. Para ello, se establece como fuente primaria para la identificación de los proyectos la información pública disponible en los registros de la Base de Datos de Obras Huérfanas del Observatorio de la Oficina de Propiedad Intelectual de la Unión Europea (EUIPO). En primer lugar, se analizan y se normalizan los datos de los 2.041 registros exportados de la citada base de datos. A continuación, se establecen diferentes rankings e indicadores. Por último, se presentan los 43 proyectos identificados, realizándose un análisis cualitativo y descriptivo de los proyectos basándose en la consulta de la información pública disponible online y en los contactos establecidos con algunos de sus responsables. This study presents an analysis of the European projects of preservation and digitisation of the cultural heritage that, as an example of good practices, have been the origin of the declaration of orphan works. For this purpose, the public information available in the records of the Orphan Works Database of the Observatory of the Intellectual Property Office of the European Union (EUIPO) is established as the primary source for the identification of projects. First, the data of the 2, 041 records exported from the database are analysed and normalized. Next, different rankings and indicators are established. Finally, the 43 projects identified are presented and a qualitative and descriptive analysis is realized, based on the consultation of the public information available online and the contacts established with some of those responsible

    Pancreatic cyst fluid harbors a unique microbiome

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    __Background:__ It is clear that specific intestinal bacteria are involved in the development of different premalignant conditions along the gastrointestinal tract. An analysis of the microbial constituents in the context of pancreatic cystic lesions has, however, as yet not been performed. This consideration prompted us to explore whether endoscopically obtained pancreatic cyst fluids (PCF) contain bacterial DNA and to determine the genera of bacteria present in such material. __Methods:__ Total DNA was isolated from 69 PCF samples. Bacterial 16S rRNA gene-specific PCR was performed followed by Sanger sequencing and de novo deep sequencing for the V3-V4 variable region of 16S rRNA gene. __Results:__ We observed that 98.2% of the samples were positive in conventional PCR, and that 100% of selected PCF samples (n = 33) were positive for bacterial microbiota as determined by next generation sequencing (NGS). Comprehensive NGS data analysis of PCF showed the presence of 408 genera of bacteria, of which 17 bacterial genera were uniquely abundant to PCF, when compared to the Human Microbiome Project (HMP) database and 15 bacterial microbiota were uniquely abundant in HMP only. Bacteroides spp., Escherichia/Shigella spp., and Acidaminococcus spp. which were predominant in PCF, while also a substantial Staphylococcus spp. and Fusobacterium spp. component was detected. __Conclusion:__ These results reveal and characterize an apparently specific bacterial ecosystem in pancreatic cyst fluid samples and may reflect the local microbiota in the pancreas. Some taxa with potential deleterious functions are present in the bacterial abundance profiles, suggesting that the unique microbiome in this specific niche may contribute to neoplastic processes in the pancreas. Further studies are needed to explore the intricate relationship between pathophysiological status in the host pancreas and its microbiota

    The impact of FDA and EMA regulatory decision-making process on the access to CFTR modulators for the treatment of cystic fibrosis

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    Background: Over the past decade, a new class of drugs called CFTR (cystic fibrosis transmembrane conductance regulator) modulators have shown to be able to improve clinical outcomes in patient with Cystic Fibrosis. In this analysis, we have extensively reviewed the regulatory pathways and decisions adopted by FDA and EMA to speed up the development, the review and the approval of these drugs, with the aim of identifying possible clinical and public health implications associated with differences. Results: CFTR modulators have been developed towards addressing three main genetic domains: (1) F508del homozygous (F508del/F508del), (2) F508del heterozygous, and (3) genotypes not carrying F508del mutation; and expanded from adult to paediatric population. Programs to expedite the reviewing and licensing of CFTR modulators were extensively adopted by FDA and EMA. All CFTR modulators have been licensed in the US as orphan drugs, but in the EU the orphan status for LUM/IVA was not confirmed at the time of marketing authorization as results from the pivotal trial were not considered clinically significant. While FDA and EMA approved CFTR modulators on the basis of results from phase III double-blind RCTs, main differences were found on the extension of indications: FDA accepted non-clinical evidence considering a recovery of the CFTR function ≥ 10% based on chloride transport, a reliable indicator to correlate with improvement in clinical outcomes. By contrast, EMA did not deem preclinical data sufficient to expand the label of CFTR modulators without confirmatory clinical data. Conclusions: Regulators played an important role in fostering the development and approval of CFTR modulators. However, differences were found between FDA and EMA in the way of reviewing and licensing CFTR modulators, which extended beyond semantics affecting patients’ eligibility and access: FDA’s approach was more mechanistic/biology-driven while the EMA’s one was more oriented by clinical evidence. This might refer to the connection between the EMA and the Member States, which tends to base decisions on pricing and reimbursement on clinical data rather than pre-clinical ones. Here we have proposed a two-step personalized-based model to merge the ethical commitment of ensuring larger access to all potential eligible patients (including those harboring very rare mutations) with the one of ensuring access to clinically assessed and effective medicines through Real World Data

    Depletion of Saccharomyces cerevisiae in psoriasis patients, restored by Dimethylfumarate therapy (DMF)

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    Background Psoriasis and inflammatory bowel disease (IBD) are chronic inflammatory diseases sharing similar pathogenic pathways. Intestinal microbial changes such as a decrease of bakers' yeast Saccharomyces cerevisiae have been reported in IBD, suggesting the presence of a gut-skin axis. Objective To investigate whether the S. cerevisiae abundance was altered in psoriasis patients versus healthy controls, and whether dimethylfumarate (DMF) interacted with this yeast. Methods Using qPCR, faecal samples were compared between psoriasis patients without DMF (n = 30), psoriasis patients with DMF (n = 28), and healthy controls (n = 32).Results Faecal S. cerevisiae abundance was decreased in psoriasis compared to healthy controls (p<0.001). Interestingly, DMF use raised S. cerevisiae levels (p<0.001). Gastrointestinal adverse-effects of DMF were correlated with a higher S. cerevisiae abundance (p = 0.010).In vitro, a direct effect of DMF on S. cerevisiae growth was observed. In addition, anti-Saccharomyces cerevisiae antibodies were not elevated in psoriasis. Conclusion The abundance of baker's yeast S. cerevisiae is decreased in psoriasis patients, but appears to b
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