1,704 research outputs found

    Horizon Fractalization in Black Strings Ungravity

    Full text link
    In this paper we study the scalar(tensor) and vector unparticle corrections for cosmic and black strings. Initially we have considered an static cosmic string ansatz from which we obtain the solution in terms of first and second kind Bessel functions. We have also obtained the solution for black string in the unparticle scenario. We could identify two regimes, namely, a gravity dominated regime and an ungravity dominated regime. In the gravity dominated regime the black string solution recovers the usual solution for black strings. The Hawking temperature was also studied in both regimes and in the ungravity dominated regime. As in the static and rotating black hole, we found a fractalization of the event horizon. This points to the fact that fractalization is a natural consequence of unparticles. Finally, we study the thermodynamic of the black string in the ungravity scenario by computing the entropy, heat capacity and free energy. For both cases we find that, depending on the region of the parameter dUd_U, we can have phase transitions.Comment: 18 pages, 6 figure

    Effects of Lorentz violation in superconductivity

    Full text link
    This paper presents the effects of Lorentz violation in superconductivity. Constructing a Lorentz-Violating Ginzburg-Landau theory of superconductivity we discuss the influence of the Lorentz-Violating tensors k^cij\hat{k}_{c}^{ij} and k^ai\hat{k}_a^i in the London's depth penetration, in the coherence length and critical magnetic field.Comment: 5 pages, 1 figure, two columns. Matches version to be published at EP

    [The Importance of Early Referral in Pediatric Acute Liver Failure]

    Get PDF
    INTRODUCTION: Acute liver failure is a rare disorder associated to high morbidity and mortality despite survival improvement through liver transplantation. The importance of a multidisciplinary approach and early referral to a pediatric liver transplantation center were important conclusions of a national meeting in 2008, from which resulted an actuation consensus. OBJECTIVES: To characterize acute liver failure admissions in a Pediatric Intensive Care Unit of the portuguese pediatric livertransplantation center. To compare results before (A) and after (B) 2008. MATERIAL AND METHODS: Observational, retrospective study during a 20 year period (1994-2014). INCLUSION CRITERIA: age < 18 years old and acute liver failure (INR ≄ 2 without vitamin K response and hepatocellular necrosis). Children with previous liver disease were excluded. RESULTS: Fifty children were included, with median age of 24.5 months. The most common etiology under 2 years old was metabolic (34.6%) and above that age was infectious (29.2%). Forty six percent were submitted to liver transplantation and 78% of them survived. Overall mortality was 34%. Median referral time was 7 days in period A (n = 35) and 2 days in period B (n = 15; p = 0.006). Pediatric risk of mortality's median was 14.7 in period A and 6.5 in B (p = 0.019). Mortality was 37% vs 26% in periods A and B, respectively (p = 0.474). DISCUSSION AND CONCLUSIONS: Overall mortality was similar to the observed in other European centers. Liver transplantation is in fact the most effective therapeutic option. After 2008, there was a reduction in referral time and cases severity on admission; however, mortality has not reduced so far.info:eu-repo/semantics/publishedVersio

    Anatomical factors in medication-related osteonecrosis of the jaws

    Get PDF
    Abstract in proceedings of the Fourth International Congress of CiiEM: Health, Well-Being and Ageing in the 21st Century, held at Egas Moniz’ University Campus in Monte de Caparica, Almada, from 3–5 June 2019.This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.info:eu-repo/semantics/publishedVersio

    Dynamics of inelastically colliding rough spheres: Relaxation of translational and rotational energy

    Full text link
    We study the exchange of kinetic energy between translational and rotational degrees of freedom for inelastic collisions of rough spheres. Even if equipartition holds in the initial state it is immediately destroyed by collisions. The simplest generalisation of the homogeneous cooling state allows for two temperatures, characterizing translational and rotational degrees of freedom separately. For times larger than a crossover frequency, which is determined by the Enskog frequency and the initial temperature, both energies decay algebraically like t−2t^{-2} with a fixed ratio of amplitudes, different from one.Comment: 5 pages, RevTeX, 2 eps figures, slightly expanded discussion, new figures with dimensionless units, added references, accepted for publication in PRE as a Rapid Com

    DiatomĂĄceas planctĂŽnicas do lago Sant'Anna (vĂĄrzea do Curuai, PA, Brasil) durante o perĂ­odo de cheia de 2004.

    Get PDF
    A vĂĄrzea do Curuai tem uma dinĂąmica especĂ­fica e Ă© bastante influenciada por perĂ­odos de cheia e vazante. AlĂ©m alterar a biota e biodiversidade, tal dinĂąmica mantĂ©m o constante aporte de matĂ©ria orgĂąnica. As diatomĂĄceas sĂŁo um grupo heterogĂȘneo, tendo espĂ©cies sensĂ­veis e outras resistentes Ă s variaçÔes ambientais. O objetivo deste trabalho Ă© inventariar a flora diatomolĂłgica do lago Sant'Anna (02°03,019S; 55°29,031W - PA-Brasil), durante o perĂ­odo de cheia de 2004. Este lago Ă© alcalino, pouco transparentes e recebe influĂȘncia do aporte lateral do rio Amazonas. Quatro estaçÔes foram amostradas utilizando rede de plĂąncton (20 m). As amostras foram fixadas em solução de Transeau 1:1 e analisadas atravĂ©s de lĂąminas permanentes (3/amostra). Os indivĂ­duos encontrados foram microfotografados e identificados atravĂ©s de literatura especĂ­fica e atualizada. Foram encontrados 58 taxa, sendo 50 Bacillariophyceae e 8 Coscinodiscophyceae. Eunotia foi o gĂȘnero mais representativo (9 taxa) seguido de Aulacoseira (7) e Gomphonema (6); Aulacoseira granulata var. granulata foi o taxon mais frequente, ocorrendo em todas as estaçÔes e Gomphonema turris foi encontrado em cerca de 80% das amostras

    Yeast immobilization systems for second-generation ethanol production: actual trends and future perspectives

    Get PDF
    Yeast immobilization with low-cost carrier materials is a suitable strategy to optimize the fermentation of lignocellulosic hydrolysates for the production of second-generation (2G) ethanol. It is defined as the physical confinement of intact cells to a certain region of space (the carrier) with the preservation of their biological activity. This technological approach facilitates promising strategies for second-generation bioethanol production due to the enhancement of the fermentation performance that is expected to be achieved. Using immobilized cells, the resistance to inhibitors contained in the hydrolysates and the co-utilization of sugars are improved, along with facilitating separation operations and the reuse of yeast in new production cycles. Until now, the most common immobilization technology used calcium alginate as a yeast carrier but other supports such as biochar or multispecies biofilm membranes have emerged as interesting alternatives. This review compiles updated information about cell carriers and yeast-cell requirements for immobilization, and the benefits and drawbacks of different immobilization systems for second-generation bioethanol production are investigated and compared. © 2021 The Authors. Biofuels, Bioproducts and Biorefining published by Society of Industrial Chemistry and John Wiley & Sons Ltd.publishedVersio

    Estimation of interdomain flexibility of N-terminus of factor H using residual dipolar couplings

    Get PDF
    Characterization of segmental flexibility is needed to understand the biological mechanisms of the very large category of functionally diverse proteins, exemplified by the regulators of complement activation, that consist of numerous compact modules or domains linked by short, potentially flexible, sequences of amino acid residues. The use of NMR-derived residual dipolar couplings (RDCs), in magnetically aligned media, to evaluate interdomain motion is established but only for two-domain proteins. We focused on the three N-terminal domains (called CCPs or SCRs) of the important complement regulator, human factor H (i.e. FH1-3). These domains cooperate to facilitate cleavage of the key complement activation-specific protein fragment, C3b, forming iC3b that no longer participates in the complement cascade. We refined a three-dimensional solution structure of recombinant FH1-3 based on nuclear Overhauser effects and RDCs. We then employed a rudimentary series of RDC datasets, collected in media containing magnetically aligned bicelles (disk-like particles formed from phospholipids) under three different conditions, to estimate interdomain motions. This circumvents a requirement of previous approaches for technically difficult collection of five independent RDC datasets. More than 80% of conformers of this predominantly extended three-domain molecule exhibit flexions of < 40 °. Such segmental flexibility (together with the local dynamics of the hypervariable loop within domain 3), could facilitate recognition of C3b via initial anchoring and eventual reorganization of modules to the conformation captured in the previously solved crystal structure of a C3b:FH1-4 complex
    • 

    corecore