1,901 research outputs found

    Genetic variation of wild American mink (Neovison vison) in the Province of Santa Cruz. Is the genetic paradox of invasive species met?

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    Las especies invasoras constituyen una amenaza para la biodiversidad nativa. El éxito de las especies invasoras pese a su baja variabilidad genética se conoce como “paradoja genética”. El visón americano (Neovison vison) fue introducido en varias regiones del planeta como Europa, Asia y América del Sur con fines peleteros. En Argentina fue introducido en la década de 1930 y, como resultado de la liberación de individuos en la na-turaleza, lograron establecerse poblaciones silvestres en la región Patagónica. El objetivo del presente trabajo es estudiar la diversidad genética de una población asilvestrada de la provincia de Santa Cruz y compararla con la de una población en cautiverio. Analizamos un fragmento de 359 pb de la región control de ADN mitocondrial y encontramos índices de variabilidad similares entre la población silvestre y la población cautiva. Al igual que en poblaciones asilvestradas de otras regiones del planeta, no se observa una reducción en la variabilidad genética en la población silvestre de Santa Cruz, probablemente como consecuencia de liberaciones y escapes recurrentes desde diversas fuentes de cautiverio.Alien species represent a threat to native biodiversity. The suc-cess of invasive species despite their reduced genetic diversity is known as “the genetic paradox”. The American mink (Neovison vison) was introduced in several regions of the world, like Europe, Asia and South America. In Argentina, they were introduced in the 1930’s by the fur industry and wild populations were established in Patagonia due to liberations and escapes. In this study, we analyzed the genetic diversity of a wild American mink population of northern Santa Cruz province and compared it with a captive population. We sequenced a 359-bp fragment of the mtDNA control region and found that genetic variability was similar between both groups. Like in other wild invasive populations, genetic variability was not reduced in the population of Santa Cruz, probably as a consequence of frequent releases and escapes from different sources of captive minks.Fil: Malerba, Martina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución. Laboratorio de Ecología y Comportamiento Animal; ArgentinaFil: Fasola, Laura. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Roesler, Carlos Ignacio. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución. Laboratorio de Ecología y Comportamiento Animal; ArgentinaFil: Pereda, Maria Inés. Aves Argentinas; ArgentinaFil: de Miguel, Andrés. Aves Argentinas; ArgentinaFil: Martina, Florencia Lucia. Aves Argentinas; ArgentinaFil: Mahler, Bettina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución. Laboratorio de Ecología y Comportamiento Animal; Argentin

    Estudio aerobiológico de la diversidad polínica y su potencial alergénico en el oasis del sur de Mendoza, Argentina

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    Los conocimientos provenientes del campo de estudio de la Aerobiología favorecen el análisis inmunológico de los alérgenos atmosféricos procedentes de polen y esporas fúngicas. Esto posibilita conocer la carga alergénica del aire en el ambiente y de esta manera, valorar mejor la relación exposición / reacción / clínica en los pacientes en tratamiento por alergias. No existen estudios previos de este tema realizados a nivel regional ni provincial en Mendoza. Una base de datos de identificación de posibles alérgenos provenientes de la polinización de espacios verdes urbanos en la ciudad de San Rafael y General Alvear contribuye a la epidemiología ambiental sobre las afecciones alérgicas respiratorias inducidas por polen y esporas. En esta presentación damos a conocer un proyecto de investigación en Aerobiología, con el fin de generar conocimiento aerobiológico de la zona urbana del oasis del sur mendocino (San Rafael y General Alvear), que contribuye a conocer la carga alergénica proveniente de granos de polen y esporas presentes en el ambiente. Para ello, se están llevando a cabo tres líneas de trabajo que consisten en: (1) el relevamiento, localización y mapeo de la vegetación urbana en floración, (2) la elaboración de una colección de referencia palinológica, y (3) el muestreo diario de aeropartículas atmosféricas urbanas. Se presentan los resultados preliminares obtenidos desde el inicio del proyecto y se muestran las líneas de trabajo que seguirá el curso de esta investigación. A futuro, los estudios aerobiológicos permitirían el desarrollo de programas de seguimiento, prevención y control en los índices de la cantidad de polen y esporas presentes en la atmósfera. Esta herramienta puede describir el potencial alergénico en espacios urbanos sus perjuicios ambientales. De esta manera, una investigación con estas características puede ser un aporte directo a la formulación de políticas de salud pública y planificación urbana de la ciudad.Fil: Guerci, Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Museo Municipal de Historia Natural San Rafael - Unidad Asociada al CCT Mendoza; Argentina. Instituto de Enseñanza Superior 9-011 del Atuel; ArgentinaFil: Rojo, Leandro David. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Museo Municipal de Historia Natural San Rafael - Unidad Asociada al CCT Mendoza; ArgentinaFil: Indiveri, Martina. Gobierno de la Provincia de Mendoza. Hospital Teodoro Schestakow.; ArgentinaFil: Nuñez Sada, Maria Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Farina, Lucia. Museo Municipal de Historia Natural San Rafael - Unidad Asociada al CCT Mendoza; ArgentinaFil: Aguilar, Mariano. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Llano, Carina Lourdes. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Mendoza; ArgentinaFil: Lucero, A.. Universidad de Mendoza; ArgentinaFil: Negreira, Gabriel Alfredo. Instituto de Enseñanza Superior 9-011 del Atuel; ArgentinaFil: Vazquez, Maria Soledad. Universidad Tecnologica Nacional. Facultad Reg.san Rafael. Instituto de Evolucion, Ecologia Historica y Ambiente. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Mendoza. Instituto de Evolucion, Ecologia Historica y Ambiente.; ArgentinaFil: Rodriguez, L. F.. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Gallardo, C. A.. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Giraudo, S. B.. Museo Municipal de Historia Natural San Rafael - Unidad Asociada al CCT Mendoza; ArgentinaXIV Encuentro del Centro Internacional de Ciencias de la TierraSan RafaelArgentinaCentro Internacional para Estudios de la TierraComisión Nacional de Energía AtómicaUniversidad Nacional de CuyoUniversidad Tecnológica Nacional. Facultad Regional San Rafae

    Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

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    Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio

    Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

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    Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

    Impacts of the Tropical Pacific/Indian Oceans on the Seasonal Cycle of the West African Monsoon

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    The current consensus is that drought has developed in the Sahel during the second half of the twentieth century as a result of remote effects of oceanic anomalies amplified by local land–atmosphere interactions. This paper focuses on the impacts of oceanic anomalies upon West African climate and specifically aims to identify those from SST anomalies in the Pacific/Indian Oceans during spring and summer seasons, when they were significant. Idealized sensitivity experiments are performed with four atmospheric general circulation models (AGCMs). The prescribed SST patterns used in the AGCMs are based on the leading mode of covariability between SST anomalies over the Pacific/Indian Oceans and summer rainfall over West Africa. The results show that such oceanic anomalies in the Pacific/Indian Ocean lead to a northward shift of an anomalous dry belt from the Gulf of Guinea to the Sahel as the season advances. In the Sahel, the magnitude of rainfall anomalies is comparable to that obtained by other authors using SST anomalies confined to the proximity of the Atlantic Ocean. The mechanism connecting the Pacific/Indian SST anomalies with West African rainfall has a strong seasonal cycle. In spring (May and June), anomalous subsidence develops over both the Maritime Continent and the equatorial Atlantic in response to the enhanced equatorial heating. Precipitation increases over continental West Africa in association with stronger zonal convergence of moisture. In addition, precipitation decreases over the Gulf of Guinea. During the monsoon peak (July and August), the SST anomalies move westward over the equatorial Pacific and the two regions where subsidence occurred earlier in the seasons merge over West Africa. The monsoon weakens and rainfall decreases over the Sahel, especially in August.Peer reviewe

    Search for heavy resonances decaying to two Higgs bosons in final states containing four b quarks

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    A search is presented for narrow heavy resonances X decaying into pairs of Higgs bosons (H) in proton-proton collisions collected by the CMS experiment at the LHC at root s = 8 TeV. The data correspond to an integrated luminosity of 19.7 fb(-1). The search considers HH resonances with masses between 1 and 3 TeV, having final states of two b quark pairs. Each Higgs boson is produced with large momentum, and the hadronization products of the pair of b quarks can usually be reconstructed as single large jets. The background from multijet and t (t) over bar events is significantly reduced by applying requirements related to the flavor of the jet, its mass, and its substructure. The signal would be identified as a peak on top of the dijet invariant mass spectrum of the remaining background events. No evidence is observed for such a signal. Upper limits obtained at 95 confidence level for the product of the production cross section and branching fraction sigma(gg -> X) B(X -> HH -> b (b) over barb (b) over bar) range from 10 to 1.5 fb for the mass of X from 1.15 to 2.0 TeV, significantly extending previous searches. For a warped extra dimension theory with amass scale Lambda(R) = 1 TeV, the data exclude radion scalar masses between 1.15 and 1.55 TeV

    Measurement of nuclear modification factors of gamma(1S)), gamma(2S), and gamma(3S) mesons in PbPb collisions at root s(NN)=5.02 TeV

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    The cross sections for ϒ(1S), ϒ(2S), and ϒ(3S) production in lead-lead (PbPb) and proton-proton (pp) collisions at √sNN = 5.02 TeV have been measured using the CMS detector at the LHC. The nuclear modification factors, RAA, derived from the PbPb-to-pp ratio of yields for each state, are studied as functions of meson rapidity and transverse momentum, as well as PbPb collision centrality. The yields of all three states are found to be significantly suppressed, and compatible with a sequential ordering of the suppression, RAA(ϒ(1S)) > RAA(ϒ(2S)) > RAA(ϒ(3S)). The suppression of ϒ(1S) is larger than that seen at √sNN = 2.76 TeV, although the two are compatible within uncertainties. The upper limit on the RAA of ϒ(3S) integrated over pT, rapidity and centrality is 0.096 at 95% confidence level, which is the strongest suppression observed for a quarkonium state in heavy ion collisions to date. © 2019 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP3.Peer reviewe

    Electroweak production of two jets in association with a Z boson in proton-proton collisions root s =13 TeV

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    A measurement of the electroweak (EW) production of two jets in association with a Z boson in proton-proton collisions at root s = 13 TeV is presented, based on data recorded in 2016 by the CMS experiment at the LHC corresponding to an integrated luminosity of 35.9 fb(-1). The measurement is performed in the lljj final state with l including electrons and muons, and the jets j corresponding to the quarks produced in the hard interaction. The measured cross section in a kinematic region defined by invariant masses m(ll) > 50 GeV, m(jj) > 120 GeV, and transverse momenta P-Tj > 25 GeV is sigma(EW) (lljj) = 534 +/- 20 (stat) fb (syst) fb, in agreement with leading-order standard model predictions. The final state is also used to perform a search for anomalous trilinear gauge couplings. No evidence is found and limits on anomalous trilinear gauge couplings associated with dimension-six operators are given in the framework of an effective field theory. The corresponding 95% confidence level intervals are -2.6 <cwww/Lambda(2) <2.6 TeV-2 and -8.4 <cw/Lambda(2) <10.1 TeV-2. The additional jet activity of events in a signal-enriched region is also studied, and the measurements are in agreement with predictions.Peer reviewe

    Measurement of t(t)over-bar normalised multi-differential cross sections in pp collisions at root s=13 TeV, and simultaneous determination of the strong coupling strength, top quark pole mass, and parton distribution functions

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    Measurement of the top quark mass using charged particles in pp collisions at root s=8 TeV

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