Aprovechamiento y mejoramiento de un suelo salino mediante el cultivo de pastos forrajeros

Soil salinity is one of the factors that limit agricultural production in vast land areas. Worldwide, some 897 million hectares show a certain degree of salinity. In Mexico, 10 % of the irrigated area is considered as affected by salinity and approximately two thirds of this is to be found in the northern part of the country. With the purpose of offering an viable alternative for improving saline soils and their vegetable cover, in the present study the effect of planting ryegrass, Sudangrass and bermuda grass, that can excrete salt and also posses physiological tolerance, was evaluated. Besides, the effect of two pant densities (1 x 106 and 2 x 106 pl ha-1) on soil total soluble salts equilibrium, cations and anions and cations in plants were also assessed. Results obtained showed a clear trend of salt content reduction in soils, as seen in a drop in electrical conductivity in saturated soil extract and also in cation and anion concentration. Bermuda grass caused a greater fall in soil salinity and no significant effects were found for plant density in soil and plant salt balance.La salinidad de los suelos es uno de los factores que limita actualmente la agricultura en grandes extensiones de tierra. A nivel mundial una superficie de aproximadamente 897 millones de hectáreas presenta algún grado de salinidad. En México se considera que un 10 % del área irrigada está afectada por salinidad y de ésta el 64 % se localiza en el norte del país. Con el propósito de plantear una alternativa para el mejoramiento y cobertura vegetal de los suelos salinos, en el presente estudio se evaluó la salinidad en un suelo cultivado con algunas especies como el zacate Sudán, ballico italiano o ryegrass y zacate bermuda, las cuales poseen propiedades excretoras de sal, como un mecanismo fisiológico de tolerancia a este factor. Así mismo, se evaluó el efecto de dos densidades de población de plantas correspondientes a 1 x 106 y 2 x 106 plantas ha-1, respectivamente en el balance de sales solubles totales, cationes y aniones en suelo y cationes en planta. Los resultados del estudio mostraron una clara tendencia de reducción de sales en el suelo por efecto del cultivo de las tres especies, expresada tanto en reducción de la conductividad eléctrica del extracto de saturación del suelo, como en reducción de la concentración de cationes y aniones formadores de sales. El zacate bermuda ocasionó una mayor reducción en la salinidad del suelo y no se observó efecto significativo de la densidad de población de plantas en el balance de sales en suelo y planta

Investigación en matemáticas, economía y ciencias sociales

El resultado de este libro que reune inquietudes académicas en torno a temas tan estudiados como los que están alrededor del maíz, del frijol o del café; y tan contemporáneos como las aplicaciones concretas de las ciencias ya citadas, al estudio de la adopción del comercio electrónico en empresas del sector agroindustrial o, el caso de la generación de biogas o energía eléctrica por medio de biodigestores. Al editar este texto e incorporarlo a la bibliografía de los temas de referencia, se enriquecen opciones de consulta para los estudiosos de esos temas en general; pero también para interesados en aspectos tan específicos como la cadena de suministro del mercado hortofrutícola en Texcoco

Mammography Services Quality Assurance: Baseline Standards for Latin America and the Caribbean

Fil: Barr, Helen. No especifíca;Fil: Blanco, Susana Alicia Ana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Ministerio de Salud. Instituto Nacional del Cáncer; ArgentinaFil: Butler, Priscilla. No especifíca;Fil: da Paz, María Angela. No especifíca;Fil: Fleitas, Ileana. No especifíca;Fil: Craig, George. No especifíca;Fil: Jimenez, Pablo. No especifíca;Fil: Luciani, Silvana. No especifíca;Fil: Manrique, Javier. No especifíca;Fil: Mazal, Jonathan. No especifíca;Fil: Medlen, Kayiba. No especifíca;Fil: MIller, Colie. No especifíca;Fil: Mora, Patricia. No especifíca;Fil: Valdez Moreno, Martha Elena. No especifíca;Fil: Mosodeen, Murrie. No especifíca;Fil: Mysler, Gustavo. No especifíca;Fil: Nuche-Berenguer, Bernardo. No especifíca;Fil: Pastel, Mary. No especifíca;Fil: Pinochet, Miguel. No especifíca;Fil: Sisney, Gale. No especifíca;Fil: Ruiz Trejo, Cesar. No especifíca;Fil: Saraiya, Mona. No especifíca;Fil: Solis, Esteban. No especifíca;Fil: Swann, Phillip. No especifíca

Garantía de calidad de los servicios de mamografía: Normas básicas para América Latina y el Caribe

Fil: Barr, Helen. No especifíca;Fil: Blanco, Susana Alicia Ana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Ministerio de Salud. Instituto Nacional del Cáncer; ArgentinaFil: Albarracín, Virginia Helena. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Priscilla, Butler. No especifíca;Fil: da Paz, María Angela. No especifíca;Fil: Fleitas, Ileana. No especifíca;Fil: Jiménez, Pablo. No especifíca;Fil: Luciani, Silvana. No especifíca;Fil: Manrique, Javier. No especifíca;Fil: Mazal, Jonathan. No especifíca;Fil: Medlen, Kayiba. No especifíca;Fil: Miller, Collie. No especifíca;Fil: Mora, Patricia. No especifíca;Fil: Valdez Moreno, Martha Elena. No especifíca;Fil: Mosodeen, Murrie. No especifíca;Fil: Mysler, Gustavo. No especifíca;Fil: Nusche Berenguer, Bernardo. No especifíca;Fil: Pastel, Mary. No especifíca;Fil: Pinochet, Miguel. No especifíca;Fil: Ruiz Trejo, Cesar. No especifíca;Fil: Sisney, Gale. No especifíca;Fil: Saraiya, Mona. No especifíca;Fil: Solis, Esteban. No especifíca;Fil: Swann, Phillip. No especifíca

Evidence for the Higgs boson decay to a bottom quark–antiquark pair

info:eu-repo/semantics/publishe

Measurement of the Splitting Function in &ITpp &ITand Pb-Pb Collisions at root&ITsNN&IT=5.02 TeV

Data from heavy ion collisions suggest that the evolution of a parton shower is modified by interactions with the color charges in the dense partonic medium created in these collisions, but it is not known where in the shower evolution the modifications occur. The momentum ratio of the two leading partons, resolved as subjets, provides information about the parton shower evolution. This substructure observable, known as the splitting function, reflects the process of a parton splitting into two other partons and has been measured for jets with transverse momentum between 140 and 500 GeV, in pp and PbPb collisions at a center-of-mass energy of 5.02 TeV per nucleon pair. In central PbPb collisions, the splitting function indicates a more unbalanced momentum ratio, compared to peripheral PbPb and pp collisions.. The measurements are compared to various predictions from event generators and analytical calculations.Peer reviewe

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

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

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

Peer reviewe

Search for dark matter in events with a leptoquark and missing transverse momentum in proton-proton collisions at 13 TeV

A search is presented for dark matter in proton-proton collisions at a center-of-mass energy of root s= 13 TeV using events with at least one high transverse momentum (p(T)) muon, at least one high-p(T) jet, and large missing transverse momentum. The data were collected with the CMS detector at the CERN LHC in 2016 and 2017, and correspond to an integrated luminosity of 77.4 fb(-1). In the examined scenario, a pair of scalar leptoquarks is assumed to be produced. One leptoquark decays to a muon and a jet while the other decays to dark matter and low-p(T) standard model particles. The signature for signal events would be significant missing transverse momentum from the dark matter in conjunction with a peak at the leptoquark mass in the invariant mass distribution of the highest p(T) muon and jet. The data are observed to be consistent with the background predicted by the standard model. For the first benchmark scenario considered, dark matter masses up to 500 GeV are excluded for leptoquark masses m(LQ) approximate to 1400 GeV, and up to 300 GeV for m(LQ) approximate to 1500 GeV. For the second benchmark scenario, dark matter masses up to 600 GeV are excluded for m(LQ) approximate to 1400 GeV. (C) 2019 The Author(s). Published by Elsevier B.V.Peer reviewe