383 research outputs found

    A micrometeorological data base for the Mexico City Metropolitan Area

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    In order to overcome the lack of the surface micrometeorological data required for air quality studies in the Mexico City Metropolitan Area (MCMA), a long-term micrometeorological campaign was carried out in this area along the 2001-year. Three micrometeorological surface stations were installed at sites located at north, north-east, and south sectors of the MCMA. Each station was equipped with a 3D ultrasonic turbulence sensor and with conventional meteorological sensors for temperature, relative humidity, pressure, global radiation, net radiation, and rain. The sampling rates were 10 Hz for the ultrasonic sensor, and 1 Hz for the conventional sensors. One-hour averages were calculated for all the meteorological parameters and for the turbulence parameters such as friction velocity, scale temperature, Monin-Obukhov length, sensible heat flux and turbulent kinetic energy, among others. A simple micrometeorological database was prepared and mounted on a free access Internet page to furnish a specialized tool to the local Authorities to be utilized in health prevention and pollution regulation applications

    Cosmic-Enu: An emulator for the non-linear neutrino power spectrum

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    Cosmology is poised to measure the neutrino mass sum MÎœM_\nu and has identified several smaller-scale observables sensitive to neutrinos, necessitating accurate predictions of neutrino clustering over a wide range of length scales. The FlowsForTheMasses non-linear perturbation theory for the massive neutrino power spectrum, ΔΜ2(k)\Delta^2_\nu(k), agrees with its companion N-body simulation at the 10%−15%10\%-15\% level for k≀1 h/k \leq 1~h/Mpc. Building upon the Mira-Titan IV emulator for the cold matter, we use FlowsForTheMasses to construct an emulator for ΔΜ2(k)\Delta^2_\nu(k) covering a large range of cosmological parameters and neutrino fractions ΩΜ,0h2≀0.01\Omega_{\nu,0} h^2 \leq 0.01, which corresponds to MΜ≀0.93M_\nu \leq 0.93~eV. Consistent with FlowsForTheMasses at the 3.5%3.5\% level, it returns a power spectrum in milliseconds. Ranking the neutrinos by initial momenta, we also emulate the power spectra of momentum deciles, providing information about their perturbed distribution function. Comparing a MÎœ=0.15M_\nu=0.15~eV model to a wide range of N-body simulation methods, we find agreement to 3%3\% for k≀3kFS=0.17 h/k \leq 3 k_\mathrm{FS} = 0.17~h/Mpc and to 19%19\% for k≀0.4 h/k \leq 0.4~h/Mpc. We find that the enhancement factor, the ratio of ΔΜ2(k)\Delta^2_\nu(k) to its linear-response equivalent, is most strongly correlated with ΩΜ,0h2\Omega_{\nu,0} h^2, and also with the clustering amplitude σ8\sigma_8. Furthermore, non-linearities enhance the free-streaming-limit scaling ∂log⁥(ΔΜ2/Δm2)/∂log⁥(MÎœ)\partial \log(\Delta^2_\nu / \Delta^2_{\rm m}) / \partial \log(M_\nu) beyond its linear value of 4, increasing the MÎœM_\nu-sensitivity of the small-scale neutrino density.Comment: 17 pages, 14 figures, 3 tables. Emulator code available at: https://github.com/upadhye/Cosmic-En

    DiagnĂłstico y mejoramiento del Rastro municipal, Zacoalco de Torres.

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    Las propuestas de mejora a corto, mediano y largo plazo para el Rastro municipal de Zacoalco de Torres, es un proyecto que se desarrollĂł en el PAP San Pedro Valencia: Programa de Sustentabilidad Socioambiental para el Desarrollo Inclusivo en el cual identificamos una problemĂĄtica que se centra en la contaminaciĂłn del medio ambiente –suelo- a causa de la mala disposiciĂłn de aguas residuales provenientes de procesos del Rastro Municipal. Esta mala gestiĂłn genera riesgos a la salud de viviendas aledañas por contaminaciĂłn de agua potable y exposiciĂłn a materia residual no tratada. Para poder proponer dichas propuestas de mejora fue necesario elaborar un diagnĂłstico/formulario en base a la normativa mexicana aplicable en los rastros municipales. De este modo se encontrĂł un total de 22 Normas Oficiales Mexicanas, de las cuales solamente 5 involucran el manejo de las aguas residuales; Estas cinco normas son: NOM-008-ZOO-1994, NOM-009-ZOO-1994, NOM-194-SSA1-2004, NOM-001-SEMARNAT-1996, NOM-002-SEMARNAT-1996. De esta forma, una vez que se aplicĂł el diagnĂłstico/formulario al director del rastro, se logrĂł identificar aquellas propuestas de mejora a corto, mediano y largo plazo para el rastro de Zacoalco de Torres. Asimismo, se buscĂł que en todo momento las propuestas fueran claras y de rĂĄpida aplicaciĂłn involucrando tanto a directivos del rastro como al director de gestiĂłn y proyectos del agua potable en el municipio.ITESO, A.C

    Emission and chemistry of organic carbon in the gas and aerosol phase at a sub-urban site near Mexico City in March 2006 during the MILAGRO study

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    Volatile organic compounds (VOCs) and carbonaceous aerosol were measured at a sub-urban site near Mexico City in March of 2006 during the MILAGRO study (Megacity Initiative: Local and Global Research Objectives). Diurnal variations of hydrocarbons, elemental carbon (EC) and hydrocarbon-like organic aerosol (HOA) were dominated by a high peak in the early morning when local emissions accumulated in a shallow boundary layer, and a minimum in the afternoon when the emissions were diluted in a significantly expanded boundary layer and, in case of the reactive gases, removed by OH. In comparison, diurnal variations of species with secondary sources such as the aldehydes, ketones, oxygenated organic aerosol (OOA) and water-soluble organic carbon (WSOC) stayed relatively high in the afternoon indicating strong photochemical formation. Emission ratios of many hydrocarbon species relative to CO were higher in Mexico City than in the U.S., but we found similar emission ratios for most oxygenated VOCs and organic aerosol. Secondary formation of acetone may be more efficient in Mexico City than in the U.S., due to higher emissions of alkane precursors from the use of liquefied petroleum gas. Secondary formation of organic aerosol was similar between Mexico City and the U.S. Combining the data for all measured gas and aerosol species, we describe the budget of total observed organic carbon (TOOC), and find that the enhancement ratio of TOOC relative to CO is conserved between the early morning and mid afternoon despite large compositional changes. Finally, the influence of biomass burning is investigated using the measurements of acetonitrile, which was found to correlate with levoglucosan in the particle phase. Diurnal variations of acetonitrile indicate a contribution from local burning sources. Scatter plots of acetonitrile versus CO suggest that the contribution of biomass burning to the enhancement of most gas and aerosol species was not dominant and perhaps not dissimilar from observations in the U.S

    Autoimmune/inflammatory syndrome induced by adjuvants: a review

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    The autoimmune/inflammatory syndrome induced by adjuvants (ASIA) includes several autoimmune conditions and phenomena that occur after exposure to substances with adjuvant activity. The spectrum of the disease is heterogeneous with respect to the clinical presentation as well as the severity of the clinical manifestations. Different substances and medical devices with adjuvant activity are currently known, such as vaccines, oils, silicones, mineral salts, lipopolysaccharides, peptidoglycans, among others. These adjuvants are immunological molecules that function through potentiation of antigen-specific immune responses. Thus, the etiopathogenesis of ASIA syndrome involves a multifactorial interaction between environmental factors and genetic predisposition, and secondary activation of the adaptive and innate arms of the immune system through various mechanisms. Although in some reported cases the ASIA syndrome improves considerably when removing the implants, there are no conclusive results for the clinical benefit of removing the implants, so it is necessary to carry out further basic, clinical and surgical investigations in order to determine the best therapeutic decision

    Pion and proton showers in the CALICE scintillator-steel analogue hadron calorimeter

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    Showers produced by positive hadrons in the highly granular CALICE scintillator-steel analogue hadron calorimeter were studied. The experimental data were collected at CERN and FNAL for single particles with initial momenta from 10 to 80 GeV/c. The calorimeter response and resolution and spatial characteristics of shower development for proton- and pion-induced showers for test beam data and simulations using Geant4 version 9.6 are compared.Comment: 26 pages, 16 figures, JINST style, changes in the author list, typos corrected, new section added, figures regrouped. Accepted for publication in JINS

    Identificación molecular de hongos fitopatógenos de fresa por PCR (ITS Y EF-1α ) y susceptibilidad a bacteriocidas de Bacillus thuringiensis.

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    La generaciĂłn de resistencias a fungicidas de algunos hongos residentes del suelo representa un riesgo biolĂłgico en la producciĂłn de fresa por lo que su identificaciĂłn permite mejores medidas de control alternas a pesticidas quĂ­micos como algunos pĂ©ptidos de origen bacteriano. Se amplificaron por PCR las secuencias ITS y EF-1α de 14 hongos aislados de muestras de suelo pertenecientes a una huerta dedicada al cultivo de fresa, los cuales fueron identificados por sus caracterĂ­sticas morfolĂłgicas dentro de los gĂ©neros Aspergillus, Fusarium, Mucor, Penicillium y Trichoderma. El anĂĄlisis de la secuencias permitieron la identificaciĂłn de las especies A. Niger, A. calidoustus, F. oxysporum, F. verticillioides, F. sporotrichioides, M. circinelloides, N. fischeri, P. menonorum, P. pinophilium y T. asperellum, comprobando previamente su patogenicidad en fresa. Se determinĂł la actividad antimicrobiana de las bacteriocinas Morricina, Kurstacina, Kenyacina, Entomocina, Tolworthcina producidas por B. thuringiensis mediante bioensayos de inhibiciĂłn en pozos y medio lĂ­quido corroborando su daño celular por microscopia de fluorescencia. Las 5 bacteriocinas ejercen una actividad inhibitoria sobre todos los aislados del gĂ©nero Fusarium y M. circinelloides evitando la esporulaciĂłn e inhibiendo su crecimiento comprobando su potencial capacidad como agentes antifĂșngicos en el biocontrol de hongos en fresa

    Measurement of Leptonic Asymmetries and Top Quark Polarization in ttbar Production

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    We present measurements of lepton (l) angular distributions in ttbar -> W+ b W- b -> l+ nu b l- nubar bbar decays produced in ppbar collisions at a center-of-mass energy of sqrt(s)=1.96TeV, where l is an electron or muon. Using data corresponding to an integrated luminosity of 5.4fb^-1, collected with the D0 detector at the Fermilab Collider, we find that the angular distributions of l- relative to anti-protons and l+ relative to protons are in agreement with each other. Combining the two distributions and correcting for detector acceptance we obtain the forward-backward asymmetry A^l_FB = (5.8 +- 5.1(stat) +- 1.3(syst))%, compared to the standard model prediction of A^l_FB (predicted) = (4.7 +- 0.1)%. This result is further combined with the measurement based on the analysis of the l+jets final state to obtain A^l_FB = (11.8 +- 3.2)%. Furthermore, we present a first study of the top-quark polarization.Comment: submitted versio

    Measurement of the semileptonic charge asymmetry in B0 meson mixing with the D0 detector

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    We present a measurement of the semileptonic mixing asymmetry for B0 mesons, a^d_{sl}, using two independent decay channels: B0 -> mu+D-X, with D- -> K+pi-pi-; and B0 -> mu+D*-X, with D*- -> antiD0 pi-, antiD0 -> K+pi- (and charge conjugate processes). We use a data sample corresponding to 10.4 fb^{-1} of ppbar collisions at sqrt(s) = 1.96 TeV, collected with the D0 experiment at the Fermilab Tevatron collider. We extract the charge asymmetries in these two channels as a function of the visible proper decay length (VPDL) of the B0 meson, correct for detector-related asymmetries using data-driven methods, and account for dilution from charge-symmetric processes using Monte Carlo simulation. The final measurement combines four signal VPDL regions for each channel, yielding a^d_{sl} = [0.68 \pm 0.45 \text{(stat.)} \pm 0.14 \text{(syst.)}]%. This is the single most precise measurement of this parameter, with uncertainties smaller than the current world average of B factory measurements.Comment: Version includes minor textual changes following peer review by journal, most notably the updating of Ref. [21] to reflect the most recent publicatio
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