546 research outputs found

    Importancia de un diagnóstico socio-histórico-cultural y educativo en las comunidades indígenas del Perú: “en busca de un nuevo paradigma para el desarrollo del país”

    Get PDF
    An alternative of crucial importance for the development of the country at present is the search for a new paradigm model for our indigenous communities, where it is necessary to know the main conditions for achieving development in its present condition, with the completion of a socio-historical-cultural and educational diagnosis. With information about the behavior of the aforementioned variables, and using data collected from various sources, it will be achieved pose a new paradigm model, applying this model in a pilot of two indigenous communities in the department of Huánuco test. The proposed model has to allow, in the near future, provide solutions to current problems in our country.Una alternativa de crucial importancia para el desarrollo del país en el momento actual es la búsqueda de un nuevo modelo de paradigma para nuestras comunidades indígenas, en donde resulta necesario conocer las principales condiciones para el logro del desarrollo en su condición actual, con la realización de un diagnóstico socio-histórico-cultural y educativo. Con la información sobre el comportamiento de las variables antes mencionadas, y tomando datos recogidos de fuentes diversas, se logrará plantear un nuevo modelo de paradigma, aplicando este modelo en una prueba piloto de dos comunidades indígenas del departamento de Huánuco. El Modelo propuesto ha de permitir, en un futuro cercano, brindar soluciones a los problemas actuales que vive nuestro país

    Level rearrangement in exotic atoms and quantum dots

    Get PDF
    A presentation and a generalisation are given of the phenomenon of level rearrangement, which occurs when an attractive long-range potential is supplemented by a short-range attractive potential of increasing strength. This problem has been discovered in condensate-matter physics and has also been studied in the physics of exotic atoms. A similar phenomenon occurs in a situation inspired by quantum dots, where a short-range interaction is added to an harmonic confinement.Comment: 12 pages, 11 figures, RevTeX

    Associated production of charged Higgs bosons and top quarks with POWHEG

    Get PDF
    The associated production of charged Higgs bosons and top quarks at hadron colliders is an important discovery channel to establish the existence of a non-minimal Higgs sector. Here, we present details of a next-to-leading order (NLO) calculation of this process using the Catani-Seymour dipole formalism and describe its implementation in POWHEG, which allows to match NLO calculations to parton showers. Numerical predictions are presented using the PYTHIA parton shower and are compared to those obtained previously at fixed order, to a leading order calculation matched to the PYTHIA parton shower, and to a different NLO calculation matched to the HERWIG parton shower with MC@NLO. We also present numerical predictions and theoretical uncertainties for various Two Higgs Doublet Models at the Tevatron and LHC.Comment: 36 page

    Gestión pedagógica y el rendimiento escolar en el área de matemática

    Get PDF
    The research aimed to demonstrate the incidence of pedagogical management in the school performance of the area of ​​mathematics in secondary school students of the educational institution Santo Domingo de Jicamarca-Lima 2018. The research is quantitative, with a type and descriptive correlational design. The data collection instrument that was used is the survey, validated by expert judgment and establishing the reliability of 0.91 on the Cronbach Alpha scale. We worked with a sample consisting of: 72 fourth-year students and 60 fifth-year students. The results show that there is a positive relationship of 0.862 between pedagogical management and school performance in the area of ​​mathematics in secondary school students; Therefore, it is concluded that it is important to make profound changes in the conception of educational environments and in the curricular field, including contents and pedagogical managements.La investigación planteó como objetivo demostrar la incidencia de la gestión pedagógica en el rendimiento escolar del área de matemática en estudiantes de educación secundaria de la institución educativa Santo Domingo de Jicamarca-Lima 2018. La investigación es cuantitativa, con un tipo y diseño descriptivo correlacional. El instrumento de recolección de datos que se utilizó es la encuesta, validado mediante juicio de expertos y estableciéndose la confiabilidad de 0.91 en la escala del Alfa de Cronbach. Se trabajó con una muestra conformada por: 72 estudiantes de cuarto año y 60 estudiantes de quinto año. Los resultados muestran que existe una relación positiva de 0.862 entre la gestión pedagógica y el rendimiento escolar del área de matemática en los estudiantes de educación secundaria; por lo que se concluye que es importante realizar profundos cambios en la concepción de los ambientes educativos y en el campo curricular, incluyendo contenidos y gestiones pedagógicas

    Gestión pedagógica y el rendimiento escolar en el área de matemática

    Get PDF
    The research aimed to demonstrate the incidence of pedagogical management in the school performance of the area of ​​mathematics in secondary school students of the educational institution Santo Domingo de Jicamarca-Lima 2018. The research is quantitative, with a type and descriptive correlational design. The data collection instrument that was used is the survey, validated by expert judgment and establishing the reliability of 0.91 on the Cronbach Alpha scale. We worked with a sample consisting of: 72 fourth-year students and 60 fifth-year students. The results show that there is a positive relationship of 0.862 between pedagogical management and school performance in the area of ​​mathematics in secondary school students; Therefore, it is concluded that it is important to make profound changes in the conception of educational environments and in the curricular field, including contents and pedagogical managements.La investigación planteó como objetivo demostrar la incidencia de la gestión pedagógica en el rendimiento escolar del área de matemática en estudiantes de educación secundaria de la institución educativa Santo Domingo de Jicamarca-Lima 2018. La investigación es cuantitativa, con un tipo y diseño descriptivo correlacional. El instrumento de recolección de datos que se utilizó es la encuesta, validado mediante juicio de expertos y estableciéndose la confiabilidad de 0.91 en la escala del Alfa de Cronbach. Se trabajó con una muestra conformada por: 72 estudiantes de cuarto año y 60 estudiantes de quinto año. Los resultados muestran que existe una relación positiva de 0.862 entre la gestión pedagógica y el rendimiento escolar del área de matemática en los estudiantes de educación secundaria; por lo que se concluye que es importante realizar profundos cambios en la concepción de los ambientes educativos y en el campo curricular, incluyendo contenidos y gestiones pedagógicas

    The portal of Neviaser: a valid option for antegrade nailing of humerus fractures

    Get PDF
    Introduction: The objective of this retrospective non-randomized study was to evaluate the portal of Neviaser (PN) as an alternative approach in antegrade humeral nailing. Methods: The surgical approach for the straight antegrade intramedullary nail (SAIN) was either the anterolateral delta-split (group 2, n = 79) or the portal of Neviaser (group 3, n = 27). Length of surgery and time of radiation were extracted from charts. Patients stabilized using the PN were followed for a clinical and radiological exam. At follow-up we evaluated the DASH (Disability of the Arm, Shoulder and Hand) and CMS (Constant-Murley Score). Results: Between 10.2015 and 12.2018 191 proximal and diaphyseal humeral fractures were operated using either an angular stable extramedullary device (group 1, PHILOS®, n = 85) or a straight humeral nail (MultiLoc®, n = 106). Time of radiation and intervention followed a normal distribution. The mean length of surgery was 172.9 min (SD 91.5) in group 1, 121.5 min (SD 54.1) in group 2 and 96.4 min (SD 33.7) in group 3 (p < 0.01). Time of radiation was significantly different with 1.1 min (SD 0.6: group 1), 3.1 min (SD 1.6: group 2) and 2.9 min (SD 1.7: group 3) (p < 0.01). After a mean interval of 21.5 months (range 6–43 months) 14 / 27 patients of group 3 were available for a clinical and radiological follow-up. The mean DASH in group 3 was 25, the CMS reached 70. The age and sex weighted CMS mean value was 96%. Forward flexion was 131°, abduction 125°. The ratio of strength affected versus non-affected side was 4.4: 6.2 kg. Conclusions: The portal of Neviaser is a feasible and safe approach and is an alternative to the anterolateral delta-split. Length of surgery and time of radiation were significantly shorter. Level of evidence: IV

    L’invasion mondiale de Drosophila suzukii : être une espèce « cousine » d’un organisme-modèle aide-t-il réellement à établir un contrôle biologique ? Espoirs, désillusions et nouvelles perspectives

    Get PDF
    L’invasion récente et rapide de Drosophila suzukii en Europe et en Amérique du Nord a suscité de nombreuses études sur le terrain comme en laboratoire. Cette drosophile est en effet à la fois un ravageur important, du fait de son développement dans des fruits à maturité, et une « cousine » de l’espèce modèle Drosophila melanogaster dont la biologie et la génétique sont bien connues. Cet article s’appuie sur les données publiées par différentes équipes et sur des résultats préliminaires pour discuter de l’avancée des recherches et notamment des questions suivantes: en quoi nos connaissances sur D. melanogaster peuvent-elles ou non aider à comprendre et gérer l’invasion de D. suzukii ? Les résultats obtenus en condition de laboratoire avec cette espèce sont-ils représentatifs de sa biologie ? Comment mesurer l’impact écologique d’une espèce invasive si la niche qu’elle vient occuper est peu décrite localement en termes d’espèces présentes et de réseaux trophiques ? Cet article discute aussi des pistes et contraintes en termes de lutte biologique et de biocontrôleThe recent and rapid invasion of Europe and North-America by Drosophila suzukii has generated numerous laboratory and field studies since this fly species is an agricultural pest that causes economical losses by laying eggs and developing in ripening fruits, but also because of its relatedness with the model species Drosophila melanogaster whose biology and genetics are well described. This commentary is based on recent data published by different research groups as well as some of our own preliminary results. It discusses the state of research on D. suzukii and addresses the main following questions: can the wide knowledge on D. melanogaster help us to understand and manage the D. suzukii invasion and how? Are lab results on D. suzukii really informative on its biology? How can the ecological impact of an invasive species be evaluated if the ecological niche is poorly described in terms of biodiversity and trophic network? We also outline constraints for the biological control of this pest species and suggest new possible approaches for its long-term managemen

    Automation of one-loop QCD corrections

    Get PDF
    We present the complete automation of the computation of one-loop QCD corrections, including UV renormalization, to an arbitrary scattering process in the Standard Model. This is achieved by embedding the OPP integrand reduction technique, as implemented in CutTools, into the MadGraph framework. By interfacing the tool so constructed, which we dub MadLoop, with MadFKS, the fully automatic computation of any infrared-safe observable at the next-to-leading order in QCD is attained. We demonstrate the flexibility and the reach of our method by calculating the production rates for a variety of processes at the 7 TeV LHC.Comment: 64 pages, 12 figures. Corrected the value of m_Z in table 1. In table 2, corrected the values of cross sections in a.4 and a.5 (previously computed with mu=mtop/2 rather than mu=mtop/4). In table 2, corrected the values of NLO cross sections in b.3, b.6, c.3, and e.7 (the symmetry factor for a few virtual channels was incorrect). In sect. A.4.3, the labeling of the four-momenta was incorrec

    Gaugino production in proton-proton collisions at a center-of-mass energy of 8 TeV

    Get PDF
    Motivated by hints for a light Standard Model-like Higgs boson and a shift in experimental attention towards electroweak supersymmetry particle production at the CERN LHC, we update in this paper our precision predictions at next-to-leading order of perturbative QCD matched to resummation at the next-to-leading logarithmic accuracy for direct gaugino pair production in proton-proton collisions with a center-of-mass energy of 8 TeV. Tables of total cross sections are presented together with the corresponding scale and parton density uncertainties for benchmark points adopted recently by the experimental collaborations, and figures are presented for up-to-date model lines attached to them. Since the experimental analyses are currently obtained with parton showers matched to multi-parton matrix elements, we also analyze the precision of this procedure by comparing invariant-mass and transverse-momentum distributions obtained in this way to those obtained with threshold and transverse-momentum resummation.Comment: 28 pages, 7 figures, 9 tables; version to appear in JHE

    b-Initiated processes at the LHC: a reappraisal

    Full text link
    Several key processes at the LHC in the standard model and beyond that involve bb quarks, such as single-top, Higgs, and weak vector boson associated production, can be described in QCD either in a 4-flavor or 5-flavor scheme. In the former, bb quarks appear only in the final state and are typically considered massive. In 5-flavor schemes, calculations include bb quarks in the initial state, are simpler and allow the resummation of possibly large initial state logarithms of the type logQ2mb2\log \frac{{\cal Q}^2}{m_b^2} into the bb parton distribution function (PDF), Q{\cal Q} being the typical scale of the hard process. In this work we critically reconsider the rationale for using 5-flavor improved schemes at the LHC. Our motivation stems from the observation that the effects of initial state logs are rarely very large in hadron collisions: 4-flavor computations are pertubatively well behaved and a substantial agreement between predictions in the two schemes is found. We identify two distinct reasons that explain this behaviour, i.e., the resummation of the initial state logarithms into the bb-PDF is relevant only at large Bjorken xx and the possibly large ratios Q2/mb2{\cal Q}^2/m_b^2's are always accompanied by universal phase space suppression factors. Our study paves the way to using both schemes for the same process so to exploit their complementary advantages for different observables, such as employing a 5-flavor scheme to accurately predict the total cross section at NNLO and the corresponding 4-flavor computation at NLO for fully exclusive studies.Comment: Fixed typo in Eq. (A.10) and few typos in Eq. (C.2) and (C.3
    corecore