15,979 research outputs found

    Applications of an exact counting formula in the Bousso-Polchinski Landscape

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    The Bousso-Polchinski (BP) Landscape is a proposal for solving the Cosmological Constant Problem. The solution requires counting the states in a very thin shell in flux space. We find an exact formula for this counting problem which has two simple asymptotic regime one of them being the method of counting low Λ\Lambda states given originally by Bousso and Polchinski. We finally give some applications of the extended formula: a robust property of the Landscape which can be identified with an effective occupation number, an estimator for the minimum cosmological constant and a possible influence on the KKLT stabilization mechanism.Comment: 43 pages, 11 figures, 2 appendices. We have added a new section (3.4) on the influence of the fraction of non-vanishing fluxes in the KKLT mechanism. Other minor changes also mad

    The good, the bad and the ugly .... of Horava gravity

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    I review the good, the bad and the ugly of the non-projectable versions of Horava gravity. I explain how this non-relativistic theory was constructed and why it was touted with such excitement as a quantum theory of gravity. I then review some of the issues facing the theory, explaining how strong coupling occurs and why this is such a problem for both phenomenology and the question of renormalisability. Finally I comment on possible violations of Equivalence Principle, and explain why these could be an issue for Blas et al's "healthy extension". This paper was presented as a talk at PASCOS 2010 in Valencia.Comment: 7 page

    AportaciĂłn al estudio de los hongos de AndalucĂ­a I. Especies nuevas o interesantes de la provincia de Granada

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    Se describen Hebeloma eburneum Malenç. como nueva cita para Europa; Cortinarius holophaeusJ. Lange, Helvella pezizoides Afz. ex Fr., Pychoverpa bohemica (Kromb.) Boud. y Russula straminea Malenç., como nuevas para España; Hebeloma pallidum Malenç., nuevo para España peninsular y finalmente se citan Geopora foliacea (Schiff. ex Boud.) Torre, Scutellinia umbrorum (Fr.) Lamb., Cortinarius herculeus Malenç., C. ionochlorus Maire, Hebeloma edurum Metrod, Myriostoma conforme (Dicks. ex Pers.) Corda, Mycenastrum corium (Guers. ex Lamb. et DC.) Desv. y Scleroderma bovista Fr., como nuevas para Andalucía.Fourteen species of fungi collected within the province of Granada, Spain, are described or mentioned here, which can be grouped as follows: Hebeloma eburneum Malenç., as new record to Europe; Cortinarius holophaeusJ. Lange, Helvella pezizoides Afz. ex Fr., Ptychoverpa bohemica (Kromb.) Boud. and Russula straminea Malenç., as new to Spain; Hebeloma pallidum Malenç., as new to Peninsular Spain, and finally Geoporafoliacea(Schff. ex Boud.) Torre, Scutellinia umbrorum (Fr.) Lamb., Cortinarius herculeus Malenç., C. ionochlorus Maire, Hebeloma edurum Metrod, Myriostoma confirme (Dicks. ex Pers.) Corda, Mycenastrum corium (Guers. ex Lamb. et DC.) Desv., and Scleroderma bovista Fr., as new records to Andalusi

    Generation of an ultrastable 578 nm laser for Yb lattice clock

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    In this paper we described the development and the characterization of a 578 nm laser source to be the clock laser for an Ytterbium Lattice Optical clock. Two independent laser sources have been realized and the characterization of the stability with a beat note technique is presente

    Mesoscopic description of boundary effects in nanoscale heat transport

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    We review some of the most important phenomena due to the phonon-wall collisions in nonlocal heat transport in nanosystems, and show how they may be described through certain slip boundary conditions in phonon hydrodynamics. Heat conduction in nanowires of different cross sections and in thin layers is analyzed, and the dependence of the thermal conductivity on the geometry, as well as on the roughness is pointed out. We also analyze the effects of the roughness of the surface of the pores on the thermal conductivity of porous silicon. Thermoelectric effects are considered as well

    Proposed experiment for the quantum "Guess my number" protocol

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    An experimental realization of the entanglement-assisted "Guess my number" protocol for the reduction of communication complexity, introduced by Steane and van Dam, would require producing and detecting three-qubit GHZ states with an efficiency eta > 0.70, which would require single photon detectors of efficiency sigma > 0.89. We propose a modification of the protocol which can be translated into a real experiment using present-day technology. In the proposed experiment, the quantum reduction of the multi-party communication complexity would require an efficiency eta > 0.05, achievable with detectors of sigma > 0.47, for four parties, and eta > 0.17 (sigma > 0.55) for three parties.Comment: REVTeX4, 4 pages, 1 figur

    The new “Vegetation map of Sicily (Italy)”: a synthetic overview of the distribution of European habitats on the territory.

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    The new "Vegetation map of Sicily (Italy)", recently published (Gianguzzi, Papini & Cusimano, 2015), shows also a synthetic overview of the distribution of European habitats in the territory; the study area has been extended to small islands circum-Sicilian (archipelago of the Aeolian; Aegadian, Pelagie Ustica and Pantelleria islands), for a total area of 25,703 km2. Our work allowed to resume the knowledge status of the phytosociological studies on vegetation carried out and to identify the actual plant landscape of the region; the map was compiled in a Geographical Information Systems (GIS) environment, in order to produce a cartographic representation in 1:10,000 scale (reduced to a 1:250,000 scale). At the reference scale 36 phytocoenotic types are represented, 16 of which related to European habitats of zonal vegetation (Mediterranean maquis, Quercus ilex woods, Quercus suber woods, Castanea sativa woods, Quercus pubescens deciduous woods, mesophilous deciduous woods, Fagus sylvatica woods, Betula aetnensis woods, woods dominated by woody gymnosperms, forest edge shrubs, orophilous pulvinate shrubs, shrublands and garrigues on substrates of carbonate nature and on substrates of siliceous nature, Ampelodesmos mauritanicus grasslands, mesophilous and sub-hygrophilous grasslands and pastures), 11 related to azonal vegetation (riparian vegetation, psammophilous herbaceous vegetation, chasmo-halophitic vegetation, etc.) and 9 related to anthropogenic vegetation (arable lands and extensive herbaceous crops, vineyards, olive groves and dry cultivation mosaics, hazelnut groves, irrigated citrus groves and orchards, greenhouses, built-up areas). Gianguzzi L., Papini F., Cusimano D., 2015 – Phytosociological survey vegetation map of Sicily (Mediterranean region). – Journal of Maps:1-7 (http://dx.doi.org/10.1080/17445647.2015.1094969)

    Preferential expression of the transcription coactivator HTIF1alpha gene in acute myeloid leukemia and MDS-related AML

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    HTIF1α, a transcription coactivator which is able to mediate RARα activity and functionally interact with PML, is encoded by a gene on chromosome 7q32–34, which is a critical region in acute myeloid leukemias (AML). With the assumption that this gene may be related to AML, we investigated the HTIF1α DNA structure and RNA expression in leukemic cells from 36 M1–M5 AML patients (28 ‘de novo’ and eight ‘secondary’ to myelodysplastic syndrome (MDS)). Abnormal HTIF1α DNA fragments were never found, whereas loss of HTIF1α DNA was observed in the patients with chromosome 7q32 deletion and translocation, and in one case without detectable chromosome 7 abnormality. HTIF1α RNA was found in acute myelocytic leukemic blasts, and was almost undetectable in normal mononuclear cells. The expression varied among the patients: higher in M1 to M3 subtypes, with the highest values in M1; low levels were constantly observed in M4 and M5 AML. In addition, HTIF1α was significantly overexpressed in MDS-related AML (MDR-AML), but not in MDS. We also found that HTIF1α expression was high in myeloid cell lines. In myeloblastic HL60 and promyelocytic NB4 cells, induced to differentiate along the monocytic–macrophage pathway by TPA or vitamin D3, HTIF1α expression decreased, whereas it was maintained at high levels on induction to granulocytic differentiation by RA or DMSO. In K562 cells, HTIF1α RNA levels did not change after hemin-induced erythroid differentiation. These results suggest that HTIF1α could play a role in myeloid differentiation, being distinctly regulated in hematopoietic lineages
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