1,390 research outputs found

    Two stories outside Boltzmann-Gibbs statistics: Mori's q-phase transitions and glassy dynamics at the onset of chaos

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    First, we analyze trajectories inside the Feigenbaum attractor and obtain the atypical weak sensitivity to initial conditions and loss of information associated to their dynamics. We identify the Mori singularities in its Lyapunov spectrum with the appearance of a special value for the entropic index q of the Tsallis statistics. Secondly, the dynamics of iterates at the noise-perturbed transition to chaos is shown to exhibit the characteristic elements of the glass transition, e.g. two-step relaxation, aging, subdiffusion and arrest. The properties of the bifurcation gap induced by the noise are seen to be comparable to those of a supercooled liquid above a glass transition temperature.Comment: Proceedings of: 31st Workshop of the International School of Solid State Physics, Complexity, Metastability and Nonextensivity, Erice (Sicily) 20-26 July 2004 World Scientific in the special series of the E. Majorana conferences, in pres

    Osteoartropatía hipertrófica pulmonar asociada a megaesófago en un perro

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    La osteoartropatía hipertrófica pulmonar (OHP) es una enfermedad de escasa presentación en la clínica rutinaria canina, secundaria a patologías intratorácicas crónicas, con lesiones que ocupan un cierto volumen intratorácico (neoplasias, abscesos, etc.), y que se caracteriza por la presencia de neoformaciones óseas en el periostio de los huesos de las extremidades. En el presente artículo se describe un caso clínico de osteoartropatía hipertrófica pulmonar (clínica, radiología, analítica sanguínea y urinaria, necropsia y estudios histopatológicos), asociada a un megaesófago, condición no descrita en la bibliografía consultada sobre la OHP canina.Hypertrophic pulmonary osteoarthropathy (HPO) is a rare clinical disease in the dog, secondary to spaceoccuping masses inside the thoracic cavity (neoplasms, abcesses, etc.) and it's characterized by neoformation of periosteal bone affecting mainly the distallimbs. The authors review the physiopathology of the disease and describe one clinical case of hypertrophic pulmonary osteoarthropathy (clinical state, radiology, blood and urine analysis, necropsy results and histologic conclusions) associated with megaesofagus, condition not yet described associated to HPO

    Impact of minority concentration on fundamental (H)D ICRF heating performance in JET-ILW

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    ITER will start its operation with non-activated hydrogen and helium plasmas at a reduced magnetic field of B-0 = 2.65 T. In hydrogen plasmas, the two ion cyclotron resonance frequency (ICRF) heating schemes available for central plasma heating (fundamental H majority and 2nd harmonic He-3 minority ICRF heating) are likely to suffer from relatively low RF wave absorption, as suggested by numerical modelling and confirmed by previous JET experiments conducted in conditions similar to those expected in ITER's initial phase. With He-4 plasmas, the commonly adopted fundamental H minority heating scheme will be used and its performance is expected to be much better. However, one important question that remains to be answered is whether increased levels of hydrogen (due to e. g. H pellet injection) jeopardize the high performance usually observed with this heating scheme, in particular in a full-metal environment. Recent JET experiments performed with the ITER-likewall shed some light onto this question and the main results concerning ICRF heating performance in L-mode discharges are summarized here

    Lorentz spaces of vector measures and real interpolation of operators

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    [EN] Using the representation of the real interpolation of spaces of p-integrable functions with respect to a vector measure, we show new factorization theorems for p-th power factorable operators acting in interpolation couples of Banach function spaces. The recently introduced Lorentz spaces of the semivariation of vector measures play a central role in the resulting factorization theorems. We apply our results to analyze extension of operators from classical weighted Lebesgue Lp-spaces ¿ in general with di¿erent weights ¿ that can be extended to their q-th powers. This is the case, for example, of the convolution operators defined by Lp-improving measures acting in Lebesgue Lp-spaces or Lorentz spaces. A new representation theorem for Banach lattices with a special lattice geometric property, as a space of vector measure integrable functions, is also proved.The fifth author acknowledges the support of the Ministerio de Economia y Competitividad (Spain) and FEDER under grant MTM2016-77054-C2-1-PDel Campo, R.; Fernández, A.; Mayoral, F.; Naranjo, F.; Sánchez Pérez, EA. (2020). Lorentz spaces of vector measures and real interpolation of operators. Quaestiones Mathematicae. 43(5-6):591-609. https://doi.org/10.2989/16073606.2019.1605413S591609435-

    Medetomidina/Atipamezol, su papel en la anestesia de animales de compañía en la clínica privada : primeras experiencias clínicas

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    En el presente trabajo, los autores revisan sus primeras experiencias clínicas sobre la utilización de una combinación de un agonista alfa-2 central: medetomidina y un agente selectivo de reversión: atipamezol, en la sedación, contención farmacológica, premedicación y anestesia de perros y gatos en la clínica diaria. Se aportan los datos de los pacientes incluidos en el estudio, los procedimientos clínicos a los que fueron sometidos, los efectos secundarios encontrados con el uso de tales medicamentos y la forma de evitarlos en la medida de lo posible o enfrentarse a ellos cuando se presentan.In this paper the authors review their first clinical experiences with a combination of an alpha-2 adrenergic central agonist: medetomidine and its reversal agent: atipamezole, in the sedation, premedication and anaesthesia of dogs and cats in clinical practice. The authors summarize data obtained from patients, the clinical procedures done, the undesirable side effects found with their use and which is their actual approach in arder to prevent them or how they manage those secondary effects when they re already present

    The sequence selectivity of KSRP explains its flexibility in the recognition of the RNA targets

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    K-homology (KH) splicing regulator protein (KSRP) is a multi-domain RNA-binding protein that regulates different steps of mRNA metabolism, from mRNA splicing to mRNA decay, interacting with a broad range of RNA sequences. To understand how KSRP recognizes its different RNA targets it is necessary to define the general rules of KSRP–RNA interaction. We describe here a complete scaffold-independent analysis of the RNA-binding potential of the four KH domains of KSRP. The analysis shows that KH3 binds to the RNA with a significantly higher affinity than the other domains and recognizes specifically a G-rich target. It also demonstrates that the other KH domains of KSRP display different sequence preferences explaining the broad range of targets recognized by the protein. Further, KSRP shows a strong negative selectivity for sequences containing several adjacent Cytosines limiting the target choice of KSRP within single-stranded RNA regions. The in-depth analysis of the RNA-binding potential of the KH domains of KSRP provides us with an understanding of the role of low sequence specificity domains in RNA recognition by multi-domain RNA-binding proteins

    A new occurence of the genus Tonkinella in northern Spain and the Middle Cambrian intercontinental correlation

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    The genus Tonkinella is a typical polimeroid trilobite in lower Middle Cambrian rocks from Vietnam, Canada, U.S.A., India, Korea, Siberia, China and Argentina. It has recently been found in the Mediterranean region (Iberian Chain, northeastern Spain). In this paper we refer the finding of Tonkinella aff. breviceps in the Leonian (lower Middle Cambrian) of the Cantabrian Mountains (northern Spain), analysing its stratigraphical position, fossil assemblages, biochronology and utility for intercontinental correlation. The presence of this taxon allows us to make a more accurate correlation between the Middle Cambrian biochronological scales of Laurentia, the Mediterranean area and China

    Estudio de los parámetros endoscópicos en 48 perros con colitis linfoplasmocitaria

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    En el presente trabajo se realiza un estudio en cuarenta y ocho perros, sobre los hallazgos endoscópicos que caracterizan a la colitislinfoplasmocitaria. La colitis linfoplasmocitaria es una enfermedad difusa que afecta en mayor o menor grado a todas las porciones del colon. Sin embargo, los resultados del estudio demuestran que el colon descendente y el colon transverso tienen mayor predisposición a presentar úlceras y erosiones, y por tanto, también a la posterior presentación de zonas de fibrosis.In this paper the gross endoscopic appearance of lymphocytic-plasmocytic colitis was studied in forty-eight dogs. Lymphocytic-plasmocytic colitis is a díffuse disease involving all the colonic portions. Nevertheless, the results of our study showed that descending and transverse colon were particularly prone to develop ulcerative and consequent fibrotic lesions

    The Role of Peripheral Amide Groups as Hydrogen-Bonding Directors in the Tubular Self-Assembly of Dinucleobase Monomers

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    Nanotubes are a fascinating kind of self‐assembled structure which have a wide interest and potential in supramolecular chemistry. We demonstrated that nanotubes of defined dimensions can be produced from dinucleobase monomers through two decoupled hierarchical cooperative processes: cyclotetramerization and supramolecular polymerization. Here we analyze the role of peripheral amide groups, which can form an array of hydrogen bonds along the tube axis, on this self‐assembly process. A combination of (1)H NMR and CD spectroscopy techniques allowed us to analyze quantitatively the thermodynamics of each of these two processes separately. We found out that the presence of these amide directors is essential to guide the polymerization event and that their nature and number have a strong influence, not only on the stabilization of the stacks of macrocycles, but also on the supramolecular polymerization mechanism

    Intermittency at critical transitions and aging dynamics at edge of chaos

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    We recall that, at both the intermittency transitions and at the Feigenbaum attractor in unimodal maps of non-linearity of order ζ>1\zeta >1, the dynamics rigorously obeys the Tsallis statistics. We account for the qq-indices and the generalized Lyapunov coefficients λq\lambda_{q} that characterize the universality classes of the pitchfork and tangent bifurcations. We identify the Mori singularities in the Lyapunov spectrum at the edge of chaos with the appearance of a special value for the entropic index qq. The physical area of the Tsallis statistics is further probed by considering the dynamics near criticality and glass formation in thermal systems. In both cases a close connection is made with states in unimodal maps with vanishing Lyapunov coefficients.Comment: Proceedings of: STATPHYS 2004 - 22nd IUPAP International Conference on Statistical Physics, National Science Seminar Complex, Indian Institute of Science, Bangalore, 4-9 July 2004. Pramana, in pres
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