129 research outputs found

    RFID en el servicio bibliotecario de la UTM

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    The central library of the Technical University of Manabí (UTM), offers the service of electronic equipment loans (laptops and tablets), in which theft has been presented. In the present article the integration of identification technologies through a web application is exposed. To do this, the requirements were raised, systems analysis and identification technologies were analyzed. Based on the study of art, the development methodology, programming languages, tools and technologies applied in the solution were described, the system architecture was designed with visual / audible alarm, the integrating system was developed and implemented and finally functional tests were carried out. As a result, it was evidenced that using bar code and RFID technology in the library service, there is better control of the entry and exit of electronic equipment, preventing any attempt at theft, and the university and general community receive a quality and speedy service.La biblioteca central de la Universidad Técnica de Manabí (Ecuador)brinda el servicio de préstamos de equipos electrónicos (portátiles y tabletas), en el que se han presentado hurtos de los mismos. En este artículo se expone la integración de RFID a través de una aplicación web. Para ello, se realizó el levantamiento de requerimientos, análisis de sistemas y de tecnologías de identificación, tomando como base el estudio del arte se describió la metodología de desarrollo, lenguajes de programación, herramientas y tecnologías aplicadas en la solución, se diseñó la arquitectura del sistema con alarma visual/sonora, se desarrolló e implantó el sistema integrador y, finalmente, se ejecutaron pruebas de funcionamiento. Como resultado se evidenció que al utilizar tecnología de código de barras y RFID en el servicio bibliotecario existe un mejor control de entrada y salida de los equipos electrónicos, previniendo de cualquier intento de hurto; a su vez, la comunidad universitaria y general recibe un servicio de calidad y rapidez

    Epigenetics and the estrogen receptor

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    The position effect variegation in Drosophila and Schizosaccharomyces pombe, and higher-order chromatin structure regulation in yeast, is orchestrated by modifier genes of the Su(var) group, (e.g., histone deacetylases ([HDACs]), protein phosphatases) and enhancer E(Var) group (e.g., ATP [adenosine 5\u27-triphosphate]-dependent nucleosome remodeling proteins). Higher-order chromatin structure is regulated in part by covalent modification of the N-terminal histone tails of chromatin, and histone tails in turn serve as platforms for recruitment of signaling modules that include nonhistone proteins such as heterochromatin protein (HP1) and NuRD. Because the enzymes governing chromatin structure through covalent modifications of histones (acetylation, methylation, phosphorylation, ubiquitination) can also target nonhistone substrates, a mechanism is in place by which epigenetic regulatory processes can affect the function of these alternate substrates. The posttranslational modification of histones, through phosphorylation and acetylation at specific residues, alters chromatin structure in an orchestrated manner in response to specific signals and is considered the basis of a histone code. In an analogous manner, specific residues within transcription factors form a signaling module within the transcription factor to determine genetic target specificity and cellular fate. The architecture of these signaling cascades in transcription factors (SCITs) are poorly understood. The regulation of estrogen receptor (ERalpha) by enzymes that convey epigenetic signals is carefully orchestrated and is reviewed here

    Horizonless Rotating Solutions in (n+1)(n+1)-dimensional Einstein-Maxwell Gravity

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    We introduce two classes of rotating solutions of Einstein-Maxwell gravity in n+1n+1 dimensions which are asymptotically anti-de Sitter type. They have no curvature singularity and no horizons. The first class of solutions, which has a conic singularity yields a spacetime with a longitudinal magnetic field and kk rotation parameters. We show that when one or more of the rotation parameters are non zero, the spinning brane has a net electric charge that is proportional to the magnitude of the rotation parameters. The second class of solutions yields a spacetime with an angular magnetic field and % \kappa boost parameters. We find that the net electric charge of these traveling branes with one or more nonzero boost parameters is proportional to the magnitude of the velocity of the brane. We also use the counterterm method inspired by AdS/CFT correspondence and calculate the conserved quantities of the solutions. We show that the logarithmic divergencies associated to the Weyl anomalies and matter field are zero, and the rr divergence of the action can be removed by the counterterm method.Comment: 14 pages, references added, Sec. II amended, an appendix added. The version to appear in Phys. Rev.

    Categorizing Different Approaches to the Cosmological Constant Problem

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    We have found that proposals addressing the old cosmological constant problem come in various categories. The aim of this paper is to identify as many different, credible mechanisms as possible and to provide them with a code for future reference. We find that they all can be classified into five different schemes of which we indicate the advantages and drawbacks. Besides, we add a new approach based on a symmetry principle mapping real to imaginary spacetime.Comment: updated version, accepted for publicatio

    Search for the standard model Higgs boson in tau final states

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    We present a search for the standard model Higgs boson using hadronically decaying tau leptons, in 1 inverse femtobarn of data collected with the D0 detector at the Fermilab Tevatron ppbar collider. We select two final states: tau plus missing transverse energy and b jets, and tau+ tau- plus jets. These final states are sensitive to a combination of associated W/Z boson plus Higgs boson, vector boson fusion and gluon-gluon fusion production processes. The observed ratio of the combined limit on the Higgs production cross section at the 95% C.L. to the standard model expectation is 29 for a Higgs boson mass of 115 GeV.Comment: publication versio

    Search for a scalar or vector particle decaying into Zgamma in ppbar collisions at sqrt(s) = 1.96 TeV

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    We present a search for a narrow scalar or vector resonance decaying into Zgamma with a subsequent Z decay into a pair of electrons or muons. The data for this search were collected with the D0 detector at the Fermilab Tevatron ppbar collider at a center of mass energy sqrt(s) = 1.96 TeV. Using 1.1 (1.0) fb-1 of data, we observe 49 (50) candidate events in the electron (muon) channel, in good agreement with the standard model prediction. From the combination of both channels, we derive 95% C.L. upper limits on the cross section times branching fraction (sigma x B) into Zgamma. These limits range from 0.19 (0.20) pb for a scalar (vector) resonance mass of 600 GeV/c^2 to 2.5 (3.1) pb for a mass of 140 GeV/c^2.Comment: Published by Phys. Lett.

    Projected WIMP sensitivity of the LUX-ZEPLIN dark matter experiment

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    LUX-ZEPLIN (LZ) is a next-generation dark matter direct detection experiment that will operate 4850 feet underground at the Sanford Underground Research Facility (SURF) in Lead, South Dakota, USA. Using a two-phase xenon detector with an active mass of 7 tonnes, LZ will search primarily for low-energy interactions with weakly interacting massive particles (WIMPs), which are hypothesized to make up the dark matter in our galactic halo. In this paper, the projected WIMP sensitivity of LZ is presented based on the latest background estimates and simulations of the detector. For a 1000 live day run using a 5.6-tonne fiducial mass, LZ is projected to exclude at 90% confidence level spin-independent WIMP-nucleon cross sections above 1.4 × 10-48cm2 for a 40 GeV/c2 mass WIMP. Additionally, a 5σ discovery potential is projected, reaching cross sections below the exclusion limits of recent experiments. For spin-dependent WIMP-neutron(-proton) scattering, a sensitivity of 2.3 × 10−43 cm2 (7.1 × 10−42 cm2) for a 40 GeV/c2 mass WIMP is expected. With underground installation well underway, LZ is on track for commissioning at SURF in 2020
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