El cuerpo seductor de las fake news en tiempos de decisiones

La Internet es un mundo abierto y las fake news son parte de su universo. En este artículo, la autora plantea que las noticias falsas ya no son noticia; circulan desde que existe el periodismo, solo que ahora su velocidad, alcances y consecuencias son de mayor amplitud. Más todavía, pone sobre la mesa el debate sobre el supuesto paralelismo entre el ejercicio del periodismo, la objetividad y la verdad absoluta. Así, concluye que las fake news son la exacerbación de un oficio que en realidad reproduce puntos de vista sobre un hecho.ITESO, A.C

De la cancha a la acción social: dos experiencias de relaciones colectivas y comunicación para el cambio social en la apropiación del espacio público y la sustentabilidad social. México/Argentina

El objetivo de este trabajo fue conocer el papel que tuvieron las relaciones colectivas y la comunicación para el cambio social durante la apropiación del espacio público y la sustentabilidad social que realizaron dos grupos de mujeres, uno en Santa Paula Segunda Sección, Tonalá, Jalisco, México (2010-2011) y el segundo en Alto Alberdi, Córdoba, Argentina (2014-2015). Con base en tales experiencias, se formularon 13 propuestas para la acción social en materia de ciudad y espacio público sustentable. La investigación se abordó con una metodología cualitativa, con algunos datos cuantitativos para contextualizar los territorios. Los resultados se plantean en cinco capítulos: 1) el abordaje del tema, a través de su descripción, limitación, justificación y pertinencia de investigación. 2) La caracterización de los vecindarios seleccionados, y descripción de casos similares en América Latina y México. 3) Un razonamiento sobre los conceptos clave y el marco teórico a través del cual se realiza el análisis. 4) El diseño metodológico con el que se trabajó el caso, y 5) los hallazgos más significativos y conclusiones de la investigación.Consejo Nacional de Ciencia y Tecnologí

Q ITESO: Análisis Crítico de Medios

En esta séptima entrega de Q ITESO: Análisis Crítico de Medios se examina un 2014 colmado de acontecimientos sobre la reconfiguración de los medios de Jalisco y del país, y sus relaciones con el estado, los empresarios y el público. Destaca la aprobación de la Ley Federal de Telecomunicaciones y Radiocomunicación y los nuevos equilibrios de poder que esto supone. También, se analizan las alianzas de algunos diarios nacionales y del estado con medios extranjeros, para compensar algunas carencias y ampliar su oferta editorial e informativa. Otras cuestiones no menos relevantes tienen que ver con la libertad de expresión y la inseguridad laboral en la que viven muchos trabajadores de los medios de comunicación jaliscienses, sobre todo los impresos, y el caso emblemático del llamado “cuarto de guerra” al servicio del gobernador del estado, Aristóteles Sandoval, para espiar -y en ocasiones hasta coaccionar- a directivos y reporteros de medios para atenuar la crítica al gobierno. El derecho a la información, la transparencia, la situación de los nuevos medios en línea, los periodistas que publican libros, el cambio climático y los periodistas que ya no están con nosotros merecen también una mirada atenta en este informe.ITESO, A.C

Measurement of the t t-bar production cross section in the dilepton channel in pp collisions at sqrt(s) = 7 TeV

The t t-bar production cross section (sigma[t t-bar]) is measured in proton-proton collisions at sqrt(s) = 7 TeV in data collected by the CMS experiment, corresponding to an integrated luminosity of 2.3 inverse femtobarns. The measurement is performed in events with two leptons (electrons or muons) in the final state, at least two jets identified as jets originating from b quarks, and the presence of an imbalance in transverse momentum. The measured value of sigma[t t-bar] for a top-quark mass of 172.5 GeV is 161.9 +/- 2.5 (stat.) +5.1/-5.0 (syst.) +/- 3.6(lumi.) pb, consistent with the prediction of the standard model.Comment: Replaced with published version. Included journal reference and DO

Search for anomalous t t-bar production in the highly-boosted all-hadronic final state

A search is presented for a massive particle, generically referred to as a Z', decaying into a t t-bar pair. The search focuses on Z' resonances that are sufficiently massive to produce highly Lorentz-boosted top quarks, which yield collimated decay products that are partially or fully merged into single jets. The analysis uses new methods to analyze jet substructure, providing suppression of the non-top multijet backgrounds. The analysis is based on a data sample of proton-proton collisions at a center-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 5 inverse femtobarns. Upper limits in the range of 1 pb are set on the product of the production cross section and branching fraction for a topcolor Z' modeled for several widths, as well as for a Randall--Sundrum Kaluza--Klein gluon. In addition, the results constrain any enhancement in t t-bar production beyond expectations of the standard model for t t-bar invariant masses larger than 1 TeV.Comment: Submitted to the Journal of High Energy Physics; this version includes a minor typo correction that will be submitted as an erratu

Combined search for the quarks of a sequential fourth generation

Results are presented from a search for a fourth generation of quarks produced singly or in pairs in a data set corresponding to an integrated luminosity of 5 inverse femtobarns recorded by the CMS experiment at the LHC in 2011. A novel strategy has been developed for a combined search for quarks of the up and down type in decay channels with at least one isolated muon or electron. Limits on the mass of the fourth-generation quarks and the relevant Cabibbo-Kobayashi-Maskawa matrix elements are derived in the context of a simple extension of the standard model with a sequential fourth generation of fermions. The existence of mass-degenerate fourth-generation quarks with masses below 685 GeV is excluded at 95% confidence level for minimal off-diagonal mixing between the third- and the fourth-generation quarks. With a mass difference of 25 GeV between the quark masses, the obtained limit on the masses of the fourth-generation quarks shifts by about +/- 20 GeV. These results significantly reduce the allowed parameter space for a fourth generation of fermions.Comment: Replaced with published version. Added journal reference and DO

Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV

A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7 TeV is presented. The data were collected at the LHC, with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. No significant excess is observed above the background expectation, and upper limits are set on the Higgs boson production cross section. The presence of the standard model Higgs boson with a mass in the 270-440 GeV range is excluded at 95% confidence level.Comment: Submitted to JHE

Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV

Results are presented from a search for a W' boson using a dataset corresponding to 5.0 inverse femtobarns of integrated luminosity collected during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV. The W' boson is modeled as a heavy W boson, but different scenarios for the couplings to fermions are considered, involving both left-handed and right-handed chiral projections of the fermions, as well as an arbitrary mixture of the two. The search is performed in the decay channel W' to t b, leading to a final state signature with a single lepton (e, mu), missing transverse energy, and jets, at least one of which is tagged as a b-jet. A W' boson that couples to fermions with the same coupling constant as the W, but to the right-handed rather than left-handed chiral projections, is excluded for masses below 1.85 TeV at the 95% confidence level. For the first time using LHC data, constraints on the W' gauge coupling for a set of left- and right-handed coupling combinations have been placed. These results represent a significant improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe

Search for New Physics with Jets and Missing Transverse Momentum in pp collisions at sqrt(s) = 7 TeV

A search for new physics is presented based on an event signature of at least three jets accompanied by large missing transverse momentum, using a data sample corresponding to an integrated luminosity of 36 inverse picobarns collected in proton--proton collisions at sqrt(s)=7 TeV with the CMS detector at the LHC. No excess of events is observed above the expected standard model backgrounds, which are all estimated from the data. Exclusion limits are presented for the constrained minimal supersymmetric extension of the standard model. Cross section limits are also presented using simplified models with new particles decaying to an undetected particle and one or two jets

Search for supersymmetry in events with b-quark jets and missing transverse energy in pp collisions at 7 TeV

Results are presented from a search for physics beyond the standard model based on events with large missing transverse energy, at least three jets, and at least one, two, or three b-quark jets. The study is performed using a sample of proton-proton collision data collected at sqrt(s) = 7 TeV with the CMS detector at the LHC in 2011. The integrated luminosity of the sample is 4.98 inverse femtobarns. The observed number of events is found to be consistent with the standard model expectation, which is evaluated using control samples in the data. The results are used to constrain cross sections for the production of supersymmetric particles decaying to b-quark-enriched final states in the context of simplified model spectra.Comment: Submitted to Physical Review