5,874 research outputs found

    El rol del control personal en la función paliativa de la justificación del sistema entre la población indígena y no indígena de estudiantes peruanos

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    Indexación: Scopus.In this article we propose a mediation model for the association between system justification and psychological well-being (i.e., the palliative function of ideology), based on system justification theory and compensatory control theory. Specifically, we argue that endorsing system-justifying beliefs leads to increased perceived personal control, which in turn predicts higher well-being. We used a convenience sample of students from two Peruvian universities. The results showed that system justification was related to general psychological well-being and personal control. In addition, indigenous students rated lower on system justification, general psychological well-being, self-esteem and personal control. Next, we found that the association between system justification and general psychological well-being was stronger among indigenous students, and this relationship was partially mediated by personal control. In addition, we showed that the mediation model is moderated by ethnicity, so that personal control is a mediator only among non-indigenous participants. We conclude that personal control is a mechanism involved in the palliative function of ideology among this group. Finally, we discuss possible explanations for the mechanisms involved in the palliative function of ideology among low-status individuals. © 2018, © 2018 Fundacion Infancia y Aprendizaje.En este artículo se propone un modelo de mediación de las relaciones entre la justificación del sistema y el bienestar psicológico (i.e., la función paliativa de la ideología) basado en las teorías de la justificación del sistema y del control compensatorio. En concreto, se propone que la adopción de creencias justificativas del sistema produce un aumento del control personal percibido que, a su vez, predice niveles más elevados de bienestar. En este estudio se utilizó una muestra por conveniencia de estudiantes provenientes de dos universidades peruanas. Los resultados muestran que la justificación del sistema está relacionada con el bienestar psicológico general y con el control personal. Además, los estudiantes indígenas mostraron niveles más reducidos de justificación del sistema, bienestar psicológico general, autoestima y control personal. También se observó que la relación entre la justificación del sistema y el bienestar psicológico general era más fuerte entre los estudiantes indígenas y que el control personal mediaba parcialmente en esta relación. Asimismo, mostramos que la etnicidad es un factor moderador del modelo de mediación, por lo que el control personal es un mediador únicamente entre los participantes no indígenas. El estudio concluye que el control personal es un mecanismo que interviene en la función paliativa de la ideología en este grupo. Por último, se discuten posibles explicaciones de los mecanismos implicados en la función paliativa de la ideología entre individuos de estatus social bajo.https://www.tandfonline.com/doi/full/10.1080/02134748.2018.153765

    Molecular biomarkers and inorganic profile to characterize Amanita ponderosa mushrooms strains

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    Amanita ponderosa are wild mushroom eatable, very appreciated in gastronomy, with high exportation potential, that grow spontaneously in some microclimates, particularly in Alentejo and Andalusia. Due to the symbiotic relation, mushrooms can accumulate high concentrations of some metals, consequently is important to estimate the trace metal contents to assessing exposure risks. Although some species of genera Amanita are toxic, others are edible and very appreciate, namely A. ponderosa that grows spontaneously in southwest of the Iberian Peninsula. Therefore is important to improve methods to characterize different Amanita strains. In this study, we intend to evaluate the inorganic composition (P, Na, K, Ca, Mg, Fe, Cu, Zn and Mn content) of several Amanita ponderosa strains and to characterise these mushrooms with molecular biomarkers. A. ponderosa strains showed different inorganic profile according to their locate area. The amplified DNA polymorphic sequences analyses by MSP-PCR allowed to identify at specie level and to differentiate A. ponderosa at strain from each origin sites

    Analytical and numerical analysis of the behaviour of RC beams flexural strengthened with CFRP

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    Experimental research regarding the flexural strengthening of reinforced concrete (RC) structures with Carbon Fibre Reinforced (CFRP) systems using the Externally Bonded Reinforcing (EBR) and the Near Surface Mounted (NSM) techniques has been carried out at the University of Minho. Considering the experimental results of this research, the performance of the ACI and fib formulations for the EBR flexural strengthening was appraised in this paper. The same was done in terms of NSM technique adopting for the CFRP debonding strain a value that is 70% of the CFRP ultimate strain, according to the recommendations of the ACI Committee 440. However, the experimental results show that the CFRP debonding strain is dependent on the CFRP percentage and existing longitudinal steel reinforcement ratio. To estimate an equation for the prediction of the CFRP debonding strain, which takes into account these parameters, a numerical model was applied to the simulation of the tests carried out.(undefined

    Conditional Mutual Information Maps as Descriptors of Net Connectivity Levels in the Brain

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    There is a growing interest in finding ways to summarize the local connectivity properties of the brain through single brain maps. Here we propose a method based on the conditional mutual information (CMI) in the frequency domain. CMI maps quantify the amount of non-redundant covariability between each site and all others in the rest of the brain, partialling out the joint variability due to gross physiological noise. Average maps from a sample of 45 healthy individuals scanned in the resting state show a clear and symmetric pattern of connectivity maxima in several regions of cortex, including prefrontal, orbitofrontal, lateral–parietal, and midline default mode network components; and in subcortical nuclei, including the amygdala, thalamus, and basal ganglia. Such cortical and subcortical hotspots of functional connectivity were more clearly evident at lower frequencies (0.02–0.1 Hz) than at higher frequencies (0.1–0.2 Hz) of endogenous oscillation. CMI mapping can also be easily applied to perform group analyses. This is exemplified by exploring effects of normal aging on CMI in a sample of healthy controls and by investigating correlations between CMI and positive psychotic symptom scores in a sample of 40 schizophrenic patients. Both the normative aging and schizophrenia studies reveal functional connectivity trends that converge with reported findings from other studies, thus giving further support to the validity of the proposed method

    Resistência de genótipos de soja a Pseudoplusia includens (Walker, 1857) (Lepidoptera: Noctuidae).

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    Este trabalho teve como objetivo avaliar as fontes químicas envolvidas na resistência de genótipos de soja à Pseudoplusia includens e o seu efeito na biologia do inseto. Os genótipos de soja BRS 231, BRS 295, Potência, IAC 24, PI 227687, foram cultivados em vasos plásticos em casa de vegetação com temperatura de 28ºC e umidade relativa de 70%. Os trifólios foram coletados e colocados em potes de acrílico contendo uma lagarta de P. includens no 2º ínstar. Estas foram levadas a câmara com temperatura de 25ºC e 80% de UR. Foram feitas avaliações diárias, até o inseto atingir a sua fase adulta. Para a avaliação dos compostos secundários, a 4ª folha trifoliada foi macerada em nitrogênio líquido em almofariz, pesado e adicionado 5ml de EtOH 80% + HCl (0,001M) e levados em banho de ultrassom durante 20 minutos. As amostras foram então centrifugadas a 14000 rpm a 4ºC por 12 minutos, secas e ressolubilizadas em MeOH 80% e filtradas em membrana Millipore® 0,45µm e analisados em HPLC-Shimadzu. A identificação dos compostos foi feito através da comparação do tempo de retenção na coluna e dos espectros dos picos obtidos com essas características dos padrões dos isoflavonóides. As isoflavonas encontradas foram: genistina, rutina, genisteína, malonil-daidzina e gliciteína. O genótipo IAC 24 causou a maior mortalidade nas lagartas, com 76%, e 96% de mortalidade nas pupas, sendo o único genótipo em que foi encontrada a gliciteína. No entanto a cultivar ?BRS 231? foi a única que apresentou as cinco substâncias analisadas. A cultivar PI 227687 apresentou maior duração do período larval, 24,11 dias, prolongando o ciclo do inseto. Além disso, a PI227687 apresentou concentrações de genistina, gliciteína e rutina, cujo obteve o maior pico, podendo essas substâncias serem prejudiciais ao inseto . Com base nos resultados apresentados pode-se inferir que o genótipo IAC 24 apresenta resistência à P. includens do tipo antibiose, podendo a gliciteína ser a substância envolvida pela resistência

    Resistência de genótipos de soja (GLYCINE MAX) a Euschistus heros (HEMIPTERA: PENTATOMIDAE).

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    A realização deste trabalho teve por objetivo avaliar a biologia de Euschistus heros em genótipos de soja e a produção de soflavonóides nesses genótipos. A soja foi cultivada em casa de vegetação, com temperatura de 28ºC e umidade relativa de 70%. Os genótipos utilizados foram: Potência, BRS 231, BRS 295 e IAC 24. Ao atingir o 2º ínstar, ninfas de E. heros, foram pesados e individualizados em placas de petri, cada uma contendo a vagem de seu respectivo genótipo. Foram mantidos em câmara com 25ºC de temperatura e 80% de UR, onde foram avaliados diariamente, até atingirem a fase adulta. Para análise das substâncias secundárias, foram realizadas a extração e quantificação das isoflavonas, cujos grãos e vagem da soja foram pesados, macerados, extraídos com metanol 80%, levados ao banho de ultrassom durante 20 minutos e centrifugadas a 14000 rpm a 4ºC por 12 minutos, filtradas em membrana Millipore® 0,45 µm e analisadas em HPLC-Shimadzu. A identificação dos compostos foi realizada por comparação do tempo de retenção na coluna e dos espectros dos picos obtidos com essas características dos padrões de ácidos fenólicos. Não houve diferença entre os genótipos quanto à duração do período ninfal. Em relação à mortalidade o genótipo IAC 24 apresentou maior taxa com 78% de ninfas mortas, o que pode causar reduções nas infestações da praga em condições de campo. As substâncias encontradas no grão da soja foram as seguintes: daidzina, glicitina, malonil-daidzina, malonil-glicitina e malonil-genistina. No entanto, foram obtidos em maior concentração em IAC 24 o que sugere haver uma relação entre essas substâncias e a alta mortalidade de percevejos neste genótipo. Portanto, conclui-se que o genótipo IAC 24 apresenta resistência à E. heros do tipo antibiose, podendo as substâncias glicitina, malonil-daidzina e malonilglicitina serem as responsáveis por essa resistência

    A lattice model for the line tension of a sessile drop

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    Within a semi--infinite thre--dimensional lattice gas model describing the coexistence of two phases on a substrate, we study, by cluster expansion techniques, the free energy (line tension) associated with the contact line between the two phases and the substrate. We show that this line tension, is given at low temperature by a convergent series whose leading term is negative, and equals 0 at zero temperature

    Growth and texture of Spark Plasma Sintered Al2O3 ceramics: a combined analysis of X-rays and Electron Back Scatter Diffraction

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    Textured alumina ceramics were obtained by Spark Plasma Sintering (SPS) of undoped commercial a-Al2O3 powders. Various parameters (density, grain growth, grain size distribution) of the alumina ceramics, sintered at two typical temperatures 1400{\deg}C and 1700{\deg}C, are investigated. Quantitative textural and structural analysis, carried out using a combination of Electron Back Scattering Diffraction (EBSD) and X-ray diffraction (XRD), are represented in the form of mapping, and pole figures. The mechanical properties of these textured alumina ceramics include high elastic modulus and hardness value with high anisotropic nature, opening the door for a large range of applicationsComment: 16 pages, 6 figures, submitted to J. Appl. Phy

    Comparison of different techniques for characterizing the diesel injector internal dimensions

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    [EN] The geometry of certain parts of diesel injectors is key to the injection, atomization and fuel-air mixing phenomena. Small variations on the geometrical parameters may have a strong influence on the aforementioned processes. Thus, OEMs need to assess their manufacturing tolerances, whereas researchers in the field (both experimentalists and modelers) rely on the accuracy of a certain metrology technique for their studies. In the current paper, an investigation of the capability of different experimental techniques to determine the geometry of a modern diesel fuel injector has been performed. For this purpose, three main elements of the injector have been evaluated: the control volume inlet and outlet orifices, together with the nozzle orifices. While the direct observation of the samples through an optical microscope is only possible for the simplest pieces, both Computed Tomography Scanning and the visualization of silicone molds technique have proven their ability to characterize the most complex internal shapes corresponding to the internal injector elements. Indeed, results indicate that the differences observed among these methodologies for the determination of the control volume inlet orifice diameter and the nozzle orifice dimensions are smaller than the uncertainties related to the experimental techniques, showing that they are both equally accurate. This implies that the choice of a given technique for the particular application of determining the geometry of diesel injectors can be done on the basis of availability, intrusion and costs, rather than on its accuracy.This work was partly sponsored by "Ministerio de Economia y Competitividad", of the Spanish Government, in the frame of the Project "Estudio de la interaccion chorro-pared en condiciones realistas de motor", Reference TRA2015-67679-c2-1-R.Salvador, FJ.; Gimeno, J.; De La Morena, J.; Carreres, M. (2018). Comparison of different techniques for characterizing the diesel injector internal dimensions. Experimental Techniques. 42(5):467-472. https://doi.org/10.1007/s40799-018-0246-1S467472425Mobasheri R, Peng Z, Mostafa S (2012) Analysis the effect of advanced injection strategies on engine performance and pollutant emissions in a heavy duty DI-diesel engine by CFD modeling. Int J Heat Fluid Flow 33(1):59–69Dhar A, Agarwal AK (2015) Experimental investigations of the effect of pilot injection on performance, emissions and combustion characteristics of Karanja biodiesel fuelled CRDI engine. Energy Convers Manag 93:357–366Mohan B, Yang W, Chou SK (2013) Fuel injection strategies for performance improvement and emissions reduction in compression ignition engines—a review. Renew Sust Energ Rev 28(x):664–676Petrovic V, Bracanovic Z, Grozdanic B, Petrovic S, Sazhin S, Knezevic D (2015) The design of a full flow dilution tunnel with a critical flow venturi for the measurement of diesel engine particulate emission. FME Trans 43(2):99–106Ilić Z, Rasuo B, Jovanović M, Janković D (2013) Impact of changing quality of air/fuel mixture during flight of a piston engine aircraft with respect to vibration low frequency spectrum. FME Trans 41(1):25–32Luján JM, Tormos B, Salvador FJ, Galgar K (2009) Comparative analysis of a DI diesel engine fuelled with biodiesel blends during the European MVEG-A cycle: Preliminaru study I. Biomass & Bioenergy 33(6–7):941–947Postrioti L, Mariani F, Battistoni M (2012) Experimental and numerical momentum flux evaluation of high pressure diesel spray. Fuel 98:149–163Payri R, Salvador FJ, Gimeno J, Venegas O (2016) A technique to match the refractive index of different diesel fuels with the refractive index of transparent materials to improve the experimental visualization. Exp Tech 40(1):261–269Duran SP, Porter JM, Parker TE (2015) Ballistic imaging of diesel sprays using a picosecond laser: characterization and demonstration. Appl Opt 54(7):1743Payri R, Salvador FJ, Gimeno J et al (2011) Flow regime effects on non-cavitating injection nozzles over spray behavior. Int J Heat Fluid Flow 32(1):273–284Koukouvinis P, Gavaises M, Li J, Wang L (2016) Large Eddy simulation of diesel injector including cavitation effects and correlation to erosion damage. Fuel 175:26–39Som S, Aggarwal SK (2010) Effects of primary breakup modeling on spray and combustion characteristics of compression ignition engines. Combust Flame 157(6):1179–1193Salvador FJ, De la Morena J, Martínez-López J, Jaramillo D (2017) Assessment of compressibility effects on internal nozzle flow in diesel injectors at very high injection pressures. Energy Convers Manag 132:221–230Salvador FJ, Gimeno J, de la Morena J, Martí-Aldaraví P (2012) Using one-dimensional modelling to analyze the influence of the use of biodiesels on the dynamic behaviour of solenoid-operated injectors in common rail systems: Results of the simulation and discussion. Energy Convers Manag 54(1):122–132Taghavifar H, Khalilarya S, Jafarmadar S, Baghery F (2016) 3-D numerical consideration of nozzle structure on combustion and emission characteristics of DI diesel injector. Appl Math Model 40(19–20):8630–8646Edelbauer W (2017) Numerical simulation of cavitating injector flow and liquid spray break-up by combination of Eulerian–Eulerian and volume-of-fluid methods. Comput Fluids 144:19–33Salvador FJ, Carreres M, Jaramillo D, Martínez-López J (2015) Comparison of microsac and VCO diesel injector nozzles in terms of internal nozzle flow characteristics. Energy Convers Manag 103:284–299Salvador FJ, Martínez-López J, Romero JV, Roselló MD (2013) Study of the influence of the needle eccentricity on the internal flow in diesel injector nozzles by computational fluid dynamics calculations. Int J Comput Math 91, no. June:24–31Payri R, Salvador FJ, Carreres M, De la Morena J (Apr. 2016) Fuel temperature influence on the performance of a last generation common-rail diesel ballistic injector. Part II: 1D model development, validation and analysis. Energy Convers Manag 114:376–391Salvador FJ, Hoyas S, Novella R, Martinez-López J (2011) Numerical simulation and extended validation of two-phase compressible flow in diesel injector nozzles. Proc Inst Mech Eng Part-D-J Automob Eng 225(D4):545–563Satkoski C, Shaver G (2011) Piezoelectric fuel injection: pulse-to-pulse coupling and flow rate estimation. IEEE/ASME Trans Mechatron 16(4):627–642Ferrari A, Mittica A (2016) Response of different injector typologies to dwell time variations and a hydraulic analysis of closely-coupled and continuous rate shaping injection schedules. Appl Energy 169:899–911Payri R, Salvador FJ, Gimeno J, De la Morena J (2011) Analysis of diesel spray atomization by means of a near-nozzle field visualization technique. At Sprays 21(9):753–774Li T, Moon S, Sato K, Yokohata H (Feb. 2017) A comprehensive study on the factors affecting near-nozzle spray dynamics of multi-hole GDI injectors. Fuel 190:292–302Yu W, Yang W, Zhao F (2017) Investigation of internal nozzle flow, spray and combustion characteristics fueled with diesel, gasoline and wide distillation fuel (WDF) based on a piezoelectric injector and a direct injection compression ignition engine. Appl Therm Eng 114:905–920Salvador FJ, Carreres M, Crialesi-Esposito M, Plazas AH (2017) Determination of critical operating and geometrical parameters in diesel injectors through one dimensional modelling, design of experiments and an analysis of variance. Proc Inst Mech Eng Part D J Automob EngMacian V, Bermúdez V, Payri R, Gimeno J (2003) New technique for determination of internal geometry of a diesel nozzle with the use of silicone methodology. Exp Tech 27, no April:39–43Piano A, Millo F, Postrioti L, Biscontini G, Cavicchi A, and Pesce FC, (2016) “Numerical and experimental assessment of a solenoid common-rail injector operation with advanced injection strategies,” SAE Int J Engines 9(1)Mitroglou N, Lorenzi M, Santini M, Gavaises M (2016) Application of X-ray micro-computed tomography on high-speed cavitating diesel fuel flows. Exp Fluids 57(11):1–14Kastengren AL, Tilocco FZ, Powell CF, Manin J, Pickett LM, Payri R, Bazyn T (2012) Engine combustion network (ECN): measurements of nozzle geometry and hydraulic behavior. At Sprays 22(12):1011–1052Otsu N (1979) A threshold selection method from gray-level histograms. IEEE Trans Syst Man Cybern 9(1):62–6
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