370 research outputs found

    “Arkansas Global Changemakers and the effect of collaborative and disruptive strategies”

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    In this essay, we consider the ways in which disruptive strategies align with collaborative strategies to produce innovations aimed at ameliorating global challenges in the twenty-first century. Specifically, we consider how they work through our current initiative, Arkansas Global Changemakers, which creates new international partnerships at the local level in order to challenge long-standing obstacles to global social change

    “Arkansas Global Changemakers and the effect of collaborative and disruptive strategies”

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    In this essay, we consider the ways in which disruptive strategies align with collaborative strategies to produce innovations aimed at ameliorating global challenges in the twenty-first century. Specifically, we consider how they work through our current initiative, Arkansas Global Changemakers, which creates new international partnerships at the local level in order to challenge long-standing obstacles to global social change

    Mechanical, antibacterial and bond strength properties of nano-titanium-enriched glass ionomer cement

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    The use of nanoparticles (NPs) has become a significant area of research in Dentistry. Objective The aim of this study was to investigate the physical, antibacterial activity and bond strength properties of conventional base, core build and restorative of glass ionomer cement (GIC) compared to GIC supplemented with titanium dioxide (TiO2) nanopowder at 3% and 5% (w/w). Material and Methods Vickers microhardness was estimated with diamond indenter. Compressive and flexural strengths were analyzed in a universal testing machine. Specimens were bonded to enamel and dentine, and tested for shear bond strength in a universal testing machine. Specimens were incubated with S. mutans suspension for evaluating antibacterial activity. Surface analysis of restorative conventional and modified GIC was performed with SEM and EDS. The analyses were carried out with Kolmogorov-Smirnov, ANOVA (post-hoc), Tukey test, Kruskal-Wallis, and Mann Whitney. Results Conventional GIC and GIC modified with TiO2 nanopowder for the base/liner cement and core build showed no differences for mechanical, antibacterial, and shear bond properties (p>;0.05). In contrast, the supplementation of TiO2 NPs to restorative GIC significantly improved Vickers microhardness (

    Father's occupational exposure to carcinogenic agents and childhood acute leukemia: a new method to assess exposure (a case-control study)

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    <p>Abstract</p> <p>Background</p> <p>Medical research has not been able to establish whether a father's occupational exposures are associated with the development of acute leukemia (AL) in their offspring. The studies conducted have weaknesses that have generated a misclassification of such exposure. Occupations and exposures to substances associated with childhood cancer are not very frequently encountered in the general population; thus, the reported risks are both inconsistent and inaccurate. In this study, to assess exposure we used a new method, an exposure index, which took into consideration the industrial branch, specific position, use of protective equipment, substances at work, degree of contact with such substances, and time of exposure. This index allowed us to obtain a grade, which permitted the identification of individuals according to their level of exposure to known or potentially carcinogenic agents that are not necessarily specifically identified as risk factors for leukemia. The aim of this study was to determine the association between a father's occupational exposure to carcinogenic agents and the presence of AL in their offspring.</p> <p>Methods</p> <p>From 1999 to 2000, a case-control study was performed with 193 children who reside in Mexico City and had been diagnosed with AL. The initial sample-size calculation was 150 children per group, assessed with an expected odds ratio (OR) of three and a minimum exposure frequency of 15.8%. These children were matched by age, sex, and institution with 193 pediatric surgical patients at secondary-care hospitals. A questionnaire was used to determine each child's background and the characteristics of the father's occupation(s). In order to determine the level of exposure to carcinogenic agents, a previously validated exposure index (occupational exposure index, OEI) was used. The consistency and validity of the index were assessed by a questionnaire comparison, the sensory recognition of the work area, and an expert's opinion.</p> <p>Results</p> <p>The adjusted ORs and 95% confidence intervals (CI) were 1.69 (0.98, 2.92) during the preconception period; 1.98 (1.13, 3.45) during the index pregnancy; 2.11 (1.17, 3.78) during breastfeeding period; 2.17 (1.28, 3.66) after birth; and 2.06 (1.24, 3.42) for global exposure.</p> <p>Conclusion</p> <p>This is the first study in which an OEI was used to assess a father's occupational exposure to carcinogenic agents as a risk factor for the development of childhood AL in his offspring. From our results, we conclude that children whose fathers have been exposed to a high level of carcinogenic agents seem to have a greater risk of developing acute leukemia. However, confounding factors cannot be disregarded due to an incomplete control for confounding.</p

    VISIONES DE LA EDUCACION FINANCIERA: Analisis y perspectivas.

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    Este libro es el resultado de un trabajo de investigación por parte de todos los autores quienes integraron los capítulos, por lo que agradecemos su confianza e interés para ser parte de este gran proyecto académico. Gracias a los enlaces de cada una de las Instituciones que aceptaron respaldar este libro: Marlen Rocío Reyes Hernández, Profesora-Investigadora de la Universidad Autónoma del Estado de México; Rogelio Valenzuela Díaz, Decano de la Facultad de Economía de la Universidad de Panamá; Samuel Alberto Moreno Peralta, Presidente del Colegio de Economistas de Panamá, a los miembros de la Asociación Mexicana de Especialistas en Educación Financiera, Asociación Valor México y la Federación de Economistas de la República Mexicana. Asimismo, hacemos una deferencia a los jóvenes talentosos que acompañaron en la coordinación del documento final, entrañables alumnos, becarios y amigos: Julio César Silva Vázquez y Alfredo Larry Vargas Hernández, que estamos convencidas que alcanzarán todas sus metas que se propongan en la vida. También es necesario reconocer a nuestras amadas familias que compartieron el tiempo de convivencia, para que lográramos la realización de este libroVisiones de la educación financiera: análisis y perspectivas es una obra que enmarca la importancia de la educación financiera en la sociedad en el contexto actual. Las decisiones que en este tema realiza un individuo pueden impactar positiva o negativamente su estabilidad económica por un periodo indeterminado, es aquí cuando la educación financiera actúa como una herramienta trascendental en su bienestar personal. Además de tener la función de armadura ante las batallas que se libran en los mercados —como la crisis financiera de 2008— funge como dinamizador de las economías al potenciar los proyectos de inversión con el aumento del emprendedurismo, impactando así en las variables macroeconómicas. Esta área del conocimiento ha adquirido importancia y popularidad a nivel internacional a raíz de las crisis económicas de los últimos años, sin embargo, aún existen, entre otras, brechas sociodemográficas, culturales, económicas, que no permiten el acceso a estas enseñanzas, excluyendo parte de la población del proceso del bienestar económico. Para ejemplificar esta desigualdad, en los capítulos se plasma un panorama internacional de la educación financiera, considerando las implicaciones y retos que han tenido las estrategias nacionales de educación financiera a nivel mundial

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

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    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

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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

    Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in pp collisions at √s = 13 TeV

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    Abstract The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric (d̂ t) and chromomagnetic (μ̂ t) moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fb−1. The linearized variable AFB(1) is used to approximate the asymmetry. Candidate t t ¯ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for t t ¯ final states. The values found for the parameters are AFB(1)=0.048−0.087+0.095(stat)−0.029+0.020(syst),μ̂t=−0.024−0.009+0.013(stat)−0.011+0.016(syst), and a limit is placed on the magnitude of | d̂ t| &lt; 0.03 at 95% confidence level. [Figure not available: see fulltext.

    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
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