57 research outputs found

    Dielectric study of the glass transition: correlation with calorimetric data

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    The glass transition in amorphous poly(ethylene terephthalate) is studied by thermally stimulated depolarization currents (TSDC) and differential scanning calorimetry (DSC). The ability of TSDC to decompose a distributed relaxation, as the glass transition, into its elementary components is demonstrated. Two polarization techniques, windows polarization (WP) and non-isothermal windows polarization (NIW), are employed to assess the influence of thermal history in the results. The Tool-Narayanaswami-Moynihan (TNM) model has been used to fit the TSDC spectra. The most important contributions to the relaxation comes from modes with non-linearity (x) around 0.7. Activation energies yield by this model are located around 1eV for polarization temperature (Tp) below 50C and they raise up to values higher than 8eV as Tp increases (up to 80C). There are few differences between results obtained with WP and NIW but, nonetheless, these are discussed. The obtained kinetic parameters are tested against DSC results in several conditions. Calculated DSC curves at several cooling and heating rates can reproduce qualitatively experimental DSC results. These results also demonstrate that modelization of the non-equilibrium kinetics involved in TSDC spectroscopy is a useful experimental tool for glass transition studies in polar polymers.Comment: 13 pages, 2 tables, 10 figures; minor change

    Clood CBR: towards microservices oriented case-based reasoning.

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    CBR applications have been deployed in a wide range of sectors, from pharmaceuticals; to defence and aerospace to IoT and transportation, to poetry and music generation; for example. However, a majority of these have been built using monolithic architectures which impose size and complexity constraints. As such these applications have a barrier to adopting new technologies and remain prohibitively expensive in both time and cost because changes in frameworks or languages affect the application directly. To address this challenge, we introduce a distributed and highly scalable generic CBR system, Clood, which is based on a microservices architecture. This splits the application into a set of smaller, interconnected services that scale to meet varying demands. Experimental results show that our Clood implementation retrieves cases at a fairly consistent rate as the casebase grows by several orders of magnitude and was over 3,700 times faster than a comparable monolithic CBR system when retrieving from half a million cases. Microservices are cloud-native architectures and with the rapid increase in cloud-computing adoption, it is timely for the CBR community to have access to such a framework

    Inhomogeneous cosmologies with Q-matter and varying Λ\Lambda

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    Starting from the inhomogeneous shear--free Nariai metric we show, by solving the Einstein--Klein--Gordon field equations, how a self--interacting scalar field plus a material fluid, a variable cosmological term and a heat flux can drive the universe to its currently observed state of homogeneous accelerated expansion. A quintessence scenario where power-law inflation takes place for a string-motivated potential in the late--time dominated field regime is proposed.Comment: 11 pages, Revtex. To be published in Physical Review

    Canonical horizontal visibility graphs are uniquely determined by their degree sequence

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    Horizontal visibility graphs (HVGs) are graphs constructed in correspondence with number sequences that have been introduced and explored recently in the context of graph-theoretical time series analysis. In most of the cases simple measures based on the degree sequence (or functionals of these such as entropies over degree and joint degree distributions) appear to be highly informative features for automatic classification and provide nontrivial information on the associated dynam- ical process, working even better than more sophisticated topological metrics. It is thus an open question why these seemingly simple measures capture so much information. Here we prove that, under suitable conditions, there exist a bijection between the adjacency matrix of an HVG and its degree sequence, and we give an explicit construction of such bijection. As a consequence, under these conditions HVGs are unigraphs and the degree sequence fully encapsulates all the information of these graphs, thereby giving a plausible reason for its apparently unreasonable effectiveness

    Laminar-turbulent transition in Raman fiber lasers:a first passage statistics based analysis

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    Loss of coherence with increasing excitation amplitudes and spatial size modulation is a fundamental problem in designing Raman fiber lasers. While it is known that ramping up laser pump power increases the amplitude of stochastic excitations, such higher energy inputs can also lead to a transition from a linearly stable coherent laminar regime to a non-desirable disordered turbulent state. This report presents a new statistical methodology, based on first passage statistics, that classifies lasing regimes in Raman fiber lasers, thereby leading to a fast and highly accurate identification of a strong instability leading to a laminar-turbulent phase transition through a self-consistently defined order parameter. The results have been consistent across a wide range of pump power values, heralding a breakthrough in the non-invasive analysis of fiber laser dynamics

    Analysis of laser radiation using the Nonlinear Fourier transform

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    Modern high-power lasers exhibit a rich diversity of nonlinear dynamics, often featuring nontrivial co-existence of linear dispersive waves and coherent structures. While the classical Fourier method adequately describes extended dispersive waves, the analysis of time-localised and/or non-stationary signals call for more nuanced approaches. Yet, mathematical methods that can be used for simultaneous characterisation of localized and extended fields are not yet well developed. Here, we demonstrate how the Nonlinear Fourier transform (NFT) based on the Zakharov-Shabat spectral problem can be applied as a signal processing tool for representation and analysis of coherent structures embedded into dispersive radiation. We use full-field, real-time experimental measurements of mode-locked pulses to compute the nonlinear pulse spectra. For the classification of lasing regimes, we present the concept of eigenvalue probability distributions. We present two field normalisation approaches, and show the NFT can yield an effective model of the laser radiation under appropriate signal normalisation conditions

    Stratification of radiosensitive brain metastases based on an actionable S100A9/RAGE resistance mechanism

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    Whole-brain radiotherapy (WBRT) is the treatment backbone for many patients with brain metastasis; however, its efficacy in preventing disease progression and the associated toxicity have questioned the clinical impact of this approach and emphasized the need for alternative treatments. Given the limited therapeutic options available for these patients and the poor understanding of the molecular mechanisms underlying the resistance of metastatic lesions to WBRT, we sought to uncover actionable targets and biomarkers that could help to refine patient selection. Through an unbiased analysis of experimental in vivo models of brain metastasis resistant to WBRT, we identified activation of the S100A9–RAGE–NF-κB–JunB pathway in brain metastases as a potential mediator of resistance in this organ. Targeting this pathway genetically or pharmacologically was sufficient to revert the WBRT resistance and increase therapeutic benefits in vivo at lower doses of radiation. In patients with primary melanoma, lung or breast adenocarcinoma developing brain metastasis, endogenous S100A9 levels in brain lesions correlated with clinical response to WBRT and underscored the potential of S100A9 levels in the blood as a noninvasive biomarker. Collectively, we provide a molecular framework to personalize WBRT and improve its efficacy through combination with a radiosensitizer that balances therapeutic benefit and toxicity.We thank all members of the Brain Metastasis Group and A. Chalmers, E. Wagner, O. Fernández-Capetillo, R. Ciérvide and A. Hidalgo for critical discussion of the manuscript; the CNIO Core Facilities for their excellent assistance; and Fox Chase Cancer Center Transgenic Facility for generation of S100A9 mice. We thank EuCOMM repository for providing S100A9 targeted embryonic stem cells. We also thank J. Massagué (MSKCC) for some of the BrM cell lines and M. Bosenberg (Yale) for the YUMM1.1 cell line. Samples from patients included in this study that provided by the Girona Biomedical Research Institute (IDIBGI) (Biobanc IDIBGI, B.0000872) are integrated into the Spanish National Biobanks Network and in the Xarxa de Bancs de Tumors de Catalunya (XBTC) financed by the Pla Director d’Oncologia de Catalunya. All patients consented to the storage of these samples in the biobank and for their use in research projects. This study was funded by MINECO (SAF2017-89643-R) (M.V.), Fundació La Marató de TV3 (201906-30-31-32) (J.B.-B., M.V. and A.C.), Fundación Ramón Areces (CIVP19S8163) (M.V.) and CIVP20S10662 (E.O.P.), Worldwide Cancer Research (19-0177) (M.V. and E.C.-J.M.), Cancer Research Institute (Clinic and Laboratory Integration Program CRI Award 2018 (54545) (M.V.), AECC (Coordinated Translational Groups 2017 (GCTRA16015SEOA) (M.V.), LAB AECC 2019 (LABAE19002VALI) (M.V.), ERC CoG (864759) (M.V.), Portuguese Foundation for Science and Technology (SFRH/bd/100089/2014) (C.M.), Boehringer-Ingelheim Fonds MD Fellowship (L.M.), La Caixa International PhD Program Fellowship-Marie Skłodowska-Curie (LCF/BQ/DI17/11620028) (P.G.-G.), La Caixa INPhINIT Fellowship (LCF/BQ/DI19/11730044) (A.P.-A.), MINECO-Severo Ochoa PhD Fellowship (BES-2017-081995) (L.A.-E.) and an AECC postdoctoral fellowship (POSTD19016PRIE) (N.P.). M.V. is an EMBO YIP member (4053). Additional support was provided by Gertrud and Erich Roggenbuck Stiftung (M.M.), Science Foundation Ireland Frontiers for the Future Award (19/FFP/6443) (L.Y.), Science Foundation Ireland Strategic Partnership Programme, Precision Oncology Ireland (18/SPP/3522) (L.Y.), Breast Cancer Now Fellowship Award with the generous support of Walk the Walk (2019AugSF1310) (D.V.), Science Foundation Ireland (20/FFP-P/8597) (D.V.), Paradifference Foundation (C.F.-T.), “la Caixa” Foundation (ID 100010434) (A.I.), European Union’s Horizon 2020 research and innovation programme under Marie Skłodowska-Curie grant agreement 847648 (CF/BQ/PI20/11760029) (A.I.), Champalimaud Centre for the Unknown (N.S.), Lisboa Regional Operational Programme (Lisboa 2020) (LISBOA01-0145-FEDER-022170) (N.S.), NCI (R01 CA227629; R01 CA218133) (S.I.G.), Fundació Roses Contra el Càncer (J.B.-B.), Ministerio de Universidades FPU Fellowship (FPU 18/00069) (P.T.), MICIN-Agencia Estatal de Investigación Fellowships (PRE2020-093032 and BES-2017-080415) (P.M. and E. Cintado, respectively), Ministerio de Ciencia, Innovación y Universidades-E050251 (PID2019-110292RB-I00) (J.L.T.), FCT (PTDC/MED-ONC/32222/2017) (C.C.F.), Fundação Millennium bcp (C.C.F.), private donations (C.C.F.) and the Foundation for Applied Cancer Research in Zurich (E.L.R. and M.W.)

    Anales de Edafología y Agrobiología Tomo 47 Número 3-4

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    Suelos. Física. Resistencia del suelo y susceptibilidad a la compactación en terrenos a monte sometidos a pastoreo. Por R. Pérez Moreira y F. Diaz-Fierros Viqueira.-- La reserva de agua útil de los suelos de Galicia. l. Relación con la textura y el contenido de materia orgánica. Por A. M. Martinez Cortizas.-- Química Empleo de aminas alifáticas en el estudio de asociaciones haloisita-esmectita en suelos. Por F. J. Aragoneses, J. Casas, y J. L. Martin de Vidales.-- Quelación por EDDHA de micronutrientes en suelos calizos. Ecuación de límite máximo. Por M. Juárez, J. Sánchez-Andréu, L. Pla y J. Jorda.-- Quelación por EDDHA de micronutrientes en suelos calizos. Ecuación de orden "n ".Por J. Sánchez-Andréu, M. Juarez, L. Pla y J. Jordá.-- Génesis, Clasificación y Cartografía Caracterización de un podsol ferro - húmico en el Puerto de la Quesera (Sierra del Ayllón). Por R. Espejo Serrano, F. Guerrero López y A. Saa Requejo.-- Natrixerales en el Baix Segre (Lleida). Por J. Bech i Borrás, J. Garrigo i Reixach y J. R. Torrento i Marselles.-- Aspectos micromorfológicos del horizonte superior en suelos artificiales (Sorribas) de las Islas Canarias. Por A. Rodríguez Rodríguez y J. M. Ontañón Sánchez.-- Fertilidad Influencia de diferentes factores del suelo sobre su contenido en microelementos asimilables: Mn, Fe, Cu y Zn. Por B. C. Ortega, Ma C. Ortega y J. G. de las Heras.--Incidencia de la salinidad del agua de riego en la mineralización del nitrógeno orgánico en suelos calizos del sureste español. Por J. García-Serna, J. Sánchez Andréu, M. Juárez y J. Mataix.-- Biología Vegetal-Fisiología Efectos de la toxicidad del flúor sobre el ciclo biológico en especies herbáceas dicotiledoneas. Por M. Ibarra, F. López Belmonte y Ma A. Diez.-- Efectos de la toxicidad del flúor sobre el ciclo biológico de especies de monocotiledoneas. Por M. Ibarra, F. López-Belmonte y Mª A . Diez.-- Proteasas ácidas en uvas Vitis vinifera (variedad Macabeo). l. Actividad proteásica durante su maduración. Por J. Marín Expósito, C. Miguel Gordillo, J. l. Maynar Mariño y J. L. Mesias Iglesias.-- Agro biología Efectos de enmiendas calcáreas en suelos fijadores de fósforo. Por S. G. Ramos Hernández y N. Aguilera Herrera.-- III. Trabajo Recapitulativo. Una deriva hacia hemiparasftismo de los líquenes epifitos: Análisis fisiológico de las relaciones con sus fitoforos. Por C. VicentePeer reviewed2019-08.- CopyBook.- Libnova.- Biblioteca IC
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