Rio de Janeiro State University

About: Rio de Janeiro State University is a education organization based out in Rio de Janeiro, Brazil. It is known for research contribution in the topics: Population & Large Hadron Collider. The organization has 16631 authors who have published 30919 publications receiving 465753 citations. The organization is also known as: UERJ & Rio de Janeiro State University.

Household food insecurity: a systematic review of the measuring instruments used in epidemiological studies.

Abstract: Objective To conduct a systematic review aimed at identifying and characterizing the experience-based household food security scales and to synthesize their psychometric properties. Design Search in the MEDLINE, LILACS and SciELO databases, using the descriptors (‘food insecurity’ OR ‘food security’) AND (‘questionnaires’ OR ‘scales’ OR ‘validity’ OR ‘reliability’). There was no limitation on the period of publication. All articles had their titles and abstracts analysed by two reviewers. The studies of interest were read in their entirety and the relevant information extracted using a standard form. Results The initial bibliographic search identified 299 articles. Of these, the 159 that seemed to meet the criteria for inclusion were read fully. After consultation of the bibliographic references of these articles, twenty articles and five documents were added, as they satisfied the previously determined criteria for inclusion. Twenty-four different instruments were identified; all were brief and of easy application. The majority were devised in the USA. Forty-seven references reported results of psychometric studies. The instruments that presented the highest number of psychometric studies were the Core Food Security Measurement/Household Food Security Survey Module (CFSM/HFSSM) and the Self-Perceived Household Food Security Scale. Conclusions There are a number of structured scales available in the literature for characterization of household food insecurity. However, despite some psychometric studies already existing about the majority of the instruments, it is observed that, except for the studies of the CFSM/HFSSM, these are still restricted to appraisal of a few aspects of reliability and validity.

Measurement of the ratio of the inclusive 3-jet cross section to the inclusive 2-jet cross section in pp collisions at √s = 7 TeV and first determination of the strong coupling constant in the TeV range

Abstract: Results of searches for heavy stable charged particles produced in pp collisions at s√ = 7 and 8 TeV are presented corresponding to an integrated luminosity of 5.0 fb−1 and 18.8 fb−1, respectively. Data collected with the CMS detector are used to study the momentum, energy deposition, and time-of-flight of signal candidates. Leptons with an electric charge between e/3 and 8e, as well as bound states that can undergo charge exchange with the detector material, are studied. Analysis results are presented for various combinations of signatures in the inner tracker only, inner tracker and muon detector, and muon detector only. Detector signatures utilized are long time-of-flight to the outer muon system and anomalously high (or low) energy deposition in the inner tracker. The data are consistent with the expected background, and upper limits are set on the production cross section of long-lived gluinos, scalar top quarks, and scalar τ leptons, as well as pair produced long-lived leptons. Corresponding lower mass limits, ranging up to 1322 GeV/c 2 for gluinos, are the most stringent to date.

Search for third-generation scalar leptoquarks and heavy right-handed neutrinos in final states with two tau leptons and two jets in proton-proton collisions at √ s = 13 TeV

Abstract: A search is performed for third-generation scalar leptoquarks and heavy right-handed neutrinos in events containing one electron or muon, one hadronically decaying tau lepton, and at least two jets, using a sqrt(s) = 13 TeV pp collision data sample corresponding to an integrated luminosity of 12.9 inverse femtobarns collected with the CMS detector at the LHC in 2016. The number of observed events is found to be in agreement with the standard model prediction. A limit is set at 95% confidence level on the product of the leptoquark pair production cross section and beta squared where beta is the branching fraction of leptoquark decay to a tau lepton and a bottom quark. Assuming beta = 1, third-generation leptoquarks with masses below 850 GeV are excluded at 95% confidence level. An additional search based on the same event topology involves heavy right-handed neutrinos, N[R], and right-handed W bosons, W[R] , arising in a left-right symmetric extension of the standard model. In this search, W[R] bosons are assumed to decay to a tau lepton and N[R] followed by the decay of the N[R] to a tau lepton and an off-shell W[R] boson. Assuming the mass of the right-handed neutrino to be half of the mass of the right-handed W boson, W[R] boson masses below 2.9 TeV are excluded at 95% confidence level. These results improve on the limits from previous searches for third-generation leptoquarks and heavy right-handed neutrinos with tau leptons in the final state.

Cosmological effects of nonlinear electrodynamics

Abstract: It will be shown that a given realization of nonlinear electrodynamics, used as a source of Einstein's equations, generates a cosmological model with interesting features, namely a phase of current cosmic acceleration, and the absence of an initial singularity, thus pointing to a way of solving two important problems in cosmology.