3,908 research outputs found

    Dialectical Interrelation Between: Problematic Situation, Real Problem, Scientific Problem, Object and Field, in the Investigation Design: A Necessary Reflection

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    All research responds to the need of solutions to a problem that directly or indirectly affects society. The development of the same largely certifies and determines the constant search for solutions. The main objective of the present study was to arrive at a clear conceptualization, as complete as possible, of some the most important terms that come up during an investigation design: Problematic Situation, Real Problem, Scientific Problem, and Object and Field, given the visible shortcomings observed in pre- and post-graduate theses when the research work is being developed and defended. The methodology consisted of basically developing a reflection around these terms (the vision that different authors have in this regard was very helpful), as well as the presentation of varied examples contributed to see the meaning of these important concepts more clearly. The study shows in a scientifically grounded way the achievement of the above. The way in which the presentation of the different concepts was handled removes any possibility of mistakes. Keywords: methodology scientific investigation, problem, object, field. Resumen Toda investigación parte del apremio en dar una respuesta a la solución de un problema que afecta de una manera directa o indirecta a la Sociedad. En gran medida, el propio desarrollo de la misma compulsa y determina esa constante búsqueda de soluciones. El objetivo principal del presente estudio fue llegar a una conceptualización clara, y lo más acabada posible, de algunos de los más importantes términos que se manejan durante el diseño de una investigación: Situación Problémica, Problema Real, Problema Científico, Objeto y Campo, dada las visibles falencias que se observan en tesistas de pre y postgrado a la hora de desarrollar y defender sus trabajos de investigación. La metodología consistió, básicamente, en desarrollar una reflexión en torno a estos términos; para lo cual resultó de gran ayuda la visión que tienen diferentes autores al respecto; así como, la exposición de variados ejemplos contribuyó a ver más definidamente el significado de estos importantes conceptos. El estudio muestra de forma científicamente fundamentada el logro de lo anterior. La forma en que se maneja la presentación de los diferentes conceptos aleja toda posibilidad de equívocos. Palabras clave: metodología investigación científica, problema, objeto, campo

    Sensitivity and Insensitivity of Galaxy Cluster Surveys to New Physics

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    We study the implications and limitations of galaxy cluster surveys for constraining models of particle physics and gravity beyond the Standard Model. Flux limited cluster counts probe the history of large scale structure formation in the universe, and as such provide useful constraints on cosmological parameters. As a result of uncertainties in some aspects of cluster dynamics, cluster surveys are currently more useful for analyzing physics that would affect the formation of structure than physics that would modify the appearance of clusters. As an example we consider the Lambda-CDM cosmology and dimming mechanisms, such as photon-axion mixing.Comment: 24 pages, 8 eps figures. References added, discussion of scatter in relations between cluster observables lengthene

    Chloroquine-containing organoruthenium complexes are fast-acting multistage antimalarial agents

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    © Cambridge University Press 2016We report the pharmacological activity of organoruthenium complexes containing chloroquine (CQ) as a chelating ligand. The complexes displayed intraerythrocytic activity against CQ-sensitive 3D7 and CQ-resistant W2 strains of Plasmodium falciparum, with potency and selectivity indexes similar to those of CQ. Complexes displayed activity against all intraerythrocytic stages, but moderate activity against Plasmodium berghei liver stages. However, unlike CQ, organoruthenium complexes impaired gametocyte viability and exhibited fast parasiticidal activity against trophozoites for P. falciparum. This functional property results from the ability of complexes to quickly induce oxidative stress. The parasitaemia of P. berghei-infected mice was reduced by treatment with the complex. Our findings demonstrated that using chloroquine for the synthesis of organoruthenium complexes retains potency and selectivity while leading to an increase in the spectrum of action and parasite killing rate relative to CQ.This research was funded by FAPESB (grant PET0042/2013, Brazil) to M.B.P.S, FAPESP (grant 14/10516-7, Brazil) to A.A.B. and Fundação para a Ciência e Tecnologia (grant PTDC/SAU-MIC/117060/2010 Portugal) to M.P. A.A.B. and M.B.P.S. are recipients of senior fellowships by CNPq (Brazil)info:eu-repo/semantics/publishedVersio

    Innovative moments and change in Career Construction Counseling

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    This article presents an exploratory study of the process of change during Career Construction Counseling (CCC). The Innovative Moments Coding System (IMCS) and the Return to the Problem Coding System (RPCS) were used to an intensive analysis of a career counseling case — the case of Michael. Both systems are grounded in a narrative conception of the self which suggests that narrative change results from the elaboration and development of narrative exceptions to a client's core problematic self-narrative. The IMCS identifies and tracks the occurrence of five different types of narrative change and the RPCS tracks the ambivalence present in the clients discourse throughout the therapeutic process. This is the first attempt to use these methods with a career counseling case. The results suggest that the narrative elaboration progresses from the first to the third session. We discuss these results, emphasizing the process of change in career counseling with clients in which maladaptive repetition underlies career decision-making difficulties

    Highlights from the Pierre Auger Observatory

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    The Pierre Auger Observatory is the world's largest cosmic ray observatory. Our current exposure reaches nearly 40,000 km2^2 str and provides us with an unprecedented quality data set. The performance and stability of the detectors and their enhancements are described. Data analyses have led to a number of major breakthroughs. Among these we discuss the energy spectrum and the searches for large-scale anisotropies. We present analyses of our Xmax_{max} data and show how it can be interpreted in terms of mass composition. We also describe some new analyses that extract mass sensitive parameters from the 100% duty cycle SD data. A coherent interpretation of all these recent results opens new directions. The consequences regarding the cosmic ray composition and the properties of UHECR sources are briefly discussed.Comment: 9 pages, 12 figures, talk given at the 33rd International Cosmic Ray Conference, Rio de Janeiro 201

    Opposite-side flavour tagging of B mesons at the LHCb experiment

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    The calibration and performance of the oppositeside flavour tagging algorithms used for the measurements of time-dependent asymmetries at the LHCb experiment are described. The algorithms have been developed using simulated events and optimized and calibrated with B + →J/ψK +, B0 →J/ψK ∗0 and B0 →D ∗− μ + νμ decay modes with 0.37 fb−1 of data collected in pp collisions at √ s = 7 TeV during the 2011 physics run. The oppositeside tagging power is determined in the B + → J/ψK + channel to be (2.10 ± 0.08 ± 0.24) %, where the first uncertainty is statistical and the second is systematic

    Search for CP violation in D+KK+π+D^{+} \to K^{-}K^{+}\pi^{+} decays

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    A model-independent search for direct CP violation in the Cabibbo suppressed decay D+KK+π+D^+ \to K^- K^+\pi^+ in a sample of approximately 370,000 decays is carried out. The data were collected by the LHCb experiment in 2010 and correspond to an integrated luminosity of 35 pb1^{-1}. The normalized Dalitz plot distributions for D+D^+ and DD^- are compared using four different binning schemes that are sensitive to different manifestations of CP violation. No evidence for CP asymmetry is found.Comment: 13 pages, 8 figures, submitted to Phys. Rev.

    Measurement of the ratio of branching fractions BR(B0 -> K*0 gamma)/BR(Bs0 -> phi gamma)

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    The ratio of branching fractions of the radiative B decays B0 -> K*0 gamma and Bs0 -> phi gamma has been measured using 0.37 fb-1 of pp collisions at a centre of mass energy of sqrt(s) = 7 TeV, collected by the LHCb experiment. The value obtained is BR(B0 -> K*0 gamma)/BR(Bs0 -> phi gamma) = 1.12 +/- 0.08 ^{+0.06}_{-0.04} ^{+0.09}_{-0.08}, where the first uncertainty is statistical, the second systematic and the third is associated to the ratio of fragmentation fractions fs/fd. Using the world average for BR(B0 -> K*0 gamma) = (4.33 +/- 0.15) x 10^{-5}, the branching fraction BR(Bs0 -> phi gamma) is measured to be (3.9 +/- 0.5) x 10^{-5}, which is the most precise measurement to date.Comment: 15 pages, 1 figure, 2 table

    Measurement of charged particle multiplicities in pppp collisions at s=7{\sqrt{s} =7}TeV in the forward region

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    The charged particle production in proton-proton collisions is studied with the LHCb detector at a centre-of-mass energy of s=7{\sqrt{s} =7}TeV in different intervals of pseudorapidity η\eta. The charged particles are reconstructed close to the interaction region in the vertex detector, which provides high reconstruction efficiency in the η\eta ranges 2.5<η<2.0-2.5<\eta<-2.0 and 2.0<η<4.52.0<\eta<4.5. The data were taken with a minimum bias trigger, only requiring one or more reconstructed tracks in the vertex detector. By selecting an event sample with at least one track with a transverse momentum greater than 1 GeV/c a hard QCD subsample is investigated. Several event generators are compared with the data; none are able to describe fully the multiplicity distributions or the charged particle density distribution as a function of η\eta. In general, the models underestimate the charged particle production

    Measurements of the branching fractions of the decays B°s → D∓s K± and B°s → D¯sπ+

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    The decay mode B°s → D∓s K± allows for one of the theoretically cleanest measurements of the CKM angle γ through the study of time-dependent CP violation. This paper reports a measurement of its branching fraction relative to the Cabibbo-favoured mode B°s → D¯sπ+ based on a data sample corresponding to 0.37 fb¯¹ of proton-proton collisions at √s = 7TeV collected in 2011 with the LHCb detector. In addition, the ratio of B meson production fractions fs/fd, determined from semileptonic decays, together with the known branching fraction of the control channel B°s → D¯sπ+ is used to perform an absolute measurement of the branching fractions: B(B°s → D¯sπ+) = (2.95 ± 0.05 ± 0.17 -0.22 +0.18) × 10¯³ ; B(B°s → D∓s K±) = (1.90 ± 0.12 ± 0.13 -0.14 +0.12) × 10¯4 ; where the first uncertainty is statistical, the second the experimental systematic uncertainty, and the third the uncertainty due to f s/f
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