831 research outputs found

    Spectra of weighted algebras of holomorphic functions

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    We consider weighted algebras of holomorphic functions on a Banach space. We determine conditions on a family of weights that assure that the corresponding weighted space is an algebra or has polynomial Schauder decompositions. We study the spectra of weighted algebras and endow them with an analytic structure. We also deal with composition operators and algebra homomorphisms, in particular to investigate how their induced mappings act on the analytic structure of the spectrum. Moreover, a Banach-Stone type question is addressed.Comment: 25 pages Corrected typo

    Boson gas in a periodic array of tubes

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    We report the thermodynamic properties of an ideal boson gas confined in an infinite periodic array of channels modeled by two, mutually perpendicular, Kronig-Penney delta-potentials. The particle's motion is hindered in the x-y directions, allowing tunneling of particles through the walls, while no confinement along the z direction is considered. It is shown that there exists a finite Bose- Einstein condensation (BEC) critical temperature Tc that decreases monotonically from the 3D ideal boson gas (IBG) value T0T_{0} as the strength of confinement P0P_{0} is increased while keeping the channel's cross section, axaya_{x}a_{y} constant. In contrast, Tc is a non-monotonic function of the cross-section area for fixed P0P_{0}. In addition to the BEC cusp, the specific heat exhibits a set of maxima and minima. The minimum located at the highest temperature is a clear signal of the confinement effect which occurs when the boson wavelength is twice the cross-section side size. This confinement is amplified when the wall strength is increased until a dimensional crossover from 3D to 1D is produced. Some of these features in the specific heat obtained from this simple model can be related, qualitatively, to at least two different experimental situations: 4^4He adsorbed within the interstitial channels of a bundle of carbon nanotubes and superconductor-multistrand-wires Nb3_{3}Sn.Comment: 9 pages, 10 figures, submitte

    Hierarchical Neutrino Mass Matrices, CP violation and Leptogenesis

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    In this work we study examples of hierarchical neutrino mass matrices inspired by family symmetries, compatible with experiments on neutrino oscillations, and for which there is a connection among the low energy CP violation phase associated to neutrino oscillations, the phases appearing in the amplitude of neutrinoless double beta decay, and the phases relevant for leptogenesis. In particular, we determine the predictions from a texture based on an underlying SU(3) family symmetry together with a GUT symmetry, and a strong hierarchy for the masses of the heavy right handed Majorana masses. We also give some examples of inverted hierarchies of neutrino masses, which may be motivated in the context of U(1) family symmetries.Comment: 34 pages. Replaced with published version -typos, corrections and references adde

    Present and Future of Parkinson’s Disease in Spain: PARKINSON-2030 Delphi Project

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    Parkinson's disease (PD) is a chronic progressive and irreversible disease and the second most common neurodegenerative disease worldwide. In Spain, it affects around 120.000-150.000 individuals, and its prevalence is estimated to increase in the future. PD has a great impact on patients' and caregivers' lives and also entails a substantial socioeconomic burden. The aim of the present study was to examine the current situation and the 10-year PD forecast for Spain in order to optimize and design future management strategies. This study was performed using the modified Delphi method to try to obtain a consensus among a panel of movement disorders experts. According to the panel, future PD management will improve diagnostic capacity and follow-up, it will include multidisciplinary teams, and innovative treatments will be developed. The expansion of new technologies and studies on biomarkers will have an impact on future PD management, leading to more accurate diagnoses, prognoses, and individualized therapies. However, the socio-economic impact of the disease will continue to be significant by 2030, especially for patients in advanced stages. This study highlighted the unmet needs in diagnosis and treatment and how crucial it is to establish recommendations for future diagnostic and therapeutic management of PD

    Revista de Vertebrados de la Estación Biológica de Doñana

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    La reproducción de Hyla meridionalis en el suroeste de EspañaAlimentación y relaciones tróficas entre larvas de Triturus marmoratus, T. alpestris y T. helveticus (Amphibia: CaudataOrganization of behaviour in isolated lizards (Gallotia galloti galloti) as revealed by multivariate analyseComposición y estructura de las comunidades de aves a lo largo de un gradiente altitudinal en tres medios arbustivos del macizo de Ayllón(Sistema Central)La comunidad de aves de un acebuchar del sur de España durante el periodo invernal y de cria.Alimentación del buho chico (Asio otus) en la isla de Tenerife y análisis comparativo con la dieta de Tyto albaAlimentación del zorzal charlo (Turdus viscivoros) en la sierra de Cazorla, SE de España.La migración en España del verderón común (Carduelis chloris, L.) según los resultados de anillamientoIdentificación de los principales quirópteros ibéricos a partir de sus dientes aislados. Valor sistemático de los caracteres morfológicos y métricos dentariosRitmo de actividad en Gazella dorcasSobre la sistemática y biología de Eliomys quercinus en la Cordillera Cantábrica.Primeras citas de Barbus microcephalus Almaça, 1967 (Ostariophysi: Cyprinidae) en EspañaSobre la presencia de Lampetra planeri BLOCH, 1784 en España.Sobre el status taxonómico del género Valencia Myers, 1928 en el suroeste de IberiaNuevas localidades de Chondrostroma polypis Steindachner, 1865 (Ostariophysi, Cyprinidae) en España.Sobre la distribución Gobio gobio (L., 1758)(OSTAOPHYSI, CIPRINIDAE) en EspañaNotas sobre la alimentación de larvas de anfibios: 2. Salamandra salamandra de CazorlaNuevos datos sobre la permanencia de caracteres larvarios en individuos adultos de una población de tritón pirenaico (Euproctus asper) en el valle de AránLa variación del diseño natural como método de reconocimiento individual en Triturus boscaiPresencia de Triturus boscai en la provincia de Córdoba.Datos sobre la alimentación de Athene cunicularia en la Reserva de fauna altoandina de Ulla-Ulla, Bolivia.Falco peregrinus cassini en BoliviaAlgunos datos sobre quirópteros de Galicia.Notas sobre la alimentación de la nutria (Lutra lutra) en el embalse de Matavacas, HuelvaPeer reviewe

    Study of CP violation in Dalitz-plot analyses of B0 --> K+K-KS, B+ --> K+K-K+, and B+ --> KSKSK+

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    We perform amplitude analyses of the decays B0K+KKS0B^0 \to K^+K^-K^0_S, B+K+KK+B^+ \rightarrow K^+K^-K^+, and B+KS0KS0K+B^+ \to K^0_S K^0_S K^+, and measure CP-violating parameters and partial branching fractions. The results are based on a data sample of approximately 470×106470\times 10^6 BBˉB\bar{B} decays, collected with the BABAR detector at the PEP-II asymmetric-energy BB factory at the SLAC National Accelerator Laboratory. For B+K+KK+B^+ \to K^+K^-K^+, we find a direct CP asymmetry in B+ϕ(1020)K+B^+ \to \phi(1020)K^+ of ACP=(12.8±4.4±1.3)A_{CP}= (12.8\pm 4.4 \pm 1.3)%, which differs from zero by 2.8σ2.8 \sigma. For B0K+KKS0B^0 \to K^+K^-K^0_S, we measure the CP-violating phase βeff(ϕ(1020)KS0)=(21±6±2)\beta_{\rm eff} (\phi(1020)K^0_S) = (21\pm 6 \pm 2)^\circ. For B+KS0KS0K+B^+ \to K^0_S K^0_S K^+, we measure an overall direct CP asymmetry of ACP=(45+4±2)A_{CP} = (4 ^{+4}_{-5} \pm 2)%. We also perform an angular-moment analysis of the three channels, and determine that the fX(1500)f_X(1500) state can be described well by the sum of the resonances f0(1500)f_0(1500), f2(1525)f_2^{\prime}(1525), and f0(1710)f_0(1710).Comment: 35 pages, 68 postscript figures. v3 - minor modifications to agree with published versio

    Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS

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    The chi_b(nP) quarkonium states are produced in proton-proton collisions at the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS detector. Using a data sample corresponding to an integrated luminosity of 4.4 fb^-1, these states are reconstructed through their radiative decays to Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes. This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table, corrected author list, matches final version in Physical Review Letter

    Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS

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    We present the results of a search for new, heavy particles that decay at a significant distance from their production point into a final state containing charged hadrons in association with a high-momentum muon. The search is conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS detector operating at the Large Hadron Collider. Production of such particles is expected in various scenarios of physics beyond the standard model. We observe no signal and place limits on the production cross-section of supersymmetric particles in an R-parity-violating scenario as a function of the neutralino lifetime. Limits are presented for different squark and neutralino masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final version to appear in Physics Letters

    Reducing heterotic M-theory to five dimensional supergravity on a manifold with boundary

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    This paper constructs the reduction of heterotic MM-theory in eleven dimensions to a supergravity model on a manifold with boundary in five dimensions using a Calabi-Yau three-fold. New results are presented for the boundary terms in the action and for the boundary conditions on the bulk fields. Some general features of dualisation on a manifold with boundary are used to explain the origin of some topological terms in the action. The effect of gaugino condensation on the fermion boundary conditions leads to a `twist' in the chirality of the gravitino which can provide an uplifting mechanism in the vacuum energy to cancel the cosmological constant after moduli stabilisation.Comment: 16 pages, RevTe
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