5,460 research outputs found

    Brain asymmetry and facial attractiveness: Facial beauty is not simply in the eye of the beholder.

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    We recently reported finding asymmetry in the appearance of beauty on the face [39]. Here we investigated whether facial beauty is a stable characteristic (on the owner's very face) or is in the perceptual space of the observer. We call the question 'the owner versus observer hypothesis'. We compared identity judgements and attractiveness ratings of observers. Subjects viewed left-left and right-right composites of faces and decided which most resembled the normal face (Experiment 1). Identity judgements (resemblance) are known to be associated with perceptual factors in the observer. Another group viewed the same normal faces and rated them on attractiveness (Experiment 2). In each experiment there were two separate viewing conditions, original and reversed (mirror-image). Lateral reversal did affect the results of Experiment 1 (confirming previous findings [3,18]) but did not affect the results of Experiment 2. The fact that lateral reversal did not affect the results of Experiment 2 suggests that facial attractiveness is more dependent on physiognomy (of the owner) and less dependent on an asymmetrical perceptual process (in the observer) than is facial identity. The results are discussed in the context of beauty’s biological significance and facial processing in the brain

    A DFT + U study on structural, electronic, vibrational and thermodynamic properties of TiO 2 polymorphs and hydrogen titanate: tuning the Hubbard ‘ U -term’

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    Structural, electronic, vibrational and thermodynamic properties have been tested when Hubbard parameter U is implemented in density functional theory calculations for TiO2 polymorphs: anatase, rutile, TiO2?B and for hydrogen titanate (H2Ti3O7) bulk. Optimum U parameter values were found for each system, balancing geometric changes and electronic properties, namely, U = 4 eV for anatase and TiO2?B, U = 5 eV for rutile and hydrogen titanate. Although the addition of this parameter improves the prediction of electronic properties, with no significant structural changes, we found that it would not be adequate for predicting vibrational properties.Fil: German, Estefania. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - BahĂ­a Blanca. Instituto de FĂ­sica del Sur. Universidad Nacional del Sur. Departamento de FĂ­sica. Instituto de FĂ­sica del Sur; Argentina. Universidad de la RepĂșblica; UruguayFil: Faccio Sgiorovello, Ricardo Juan. Universidad de la RepĂșblica; UruguayFil: MombrĂș, Alvaro W. Universidad de la RepĂșblica; Urugua

    Separation of suspended particles by arrays of obstacles in microfluidic devices

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    The stochastic transport of suspended particles through a periodic pattern of obstacles in microfluidic devices is investigated by means of the Fokker-Planck equation. Asymmetric arrays of obstacles have been shown to induce the continuous separation of DNA molecules of different length. The analysis presented here of the asymptotic distribution of particles in a unit cell of these systems shows that separation is only possible in the presence of a driving force with a non-vanishing normal component at the surface of the solid obstacles. In addition, vector separation, in which different species move, in average, in different directions within the device, is driven by differences on the force acting on the various particles and not by differences in the diffusion coefficient. Monte-Carlo simulations performed for different particles and force fields agree with the numerical solutions of the Fokker-Planck equation in the periodic system

    Searching for Dark Matter Annihilation in the Smith High-Velocity Cloud

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    Recent observations suggest that some high-velocity clouds may be confined by massive dark matter halos. In particular, the proximity and proposed dark matter content of the Smith Cloud make it a tempting target for the indirect detection of dark matter annihilation. We argue that the Smith Cloud may be a better target than some Milky Way dwarf spheroidal satellite galaxies and use gamma-ray observations from the Fermi Large Area Telescope to search for a dark matter annihilation signal. No significant gamma-ray excess is found coincident with the Smith Cloud, and we set strong limits on the dark matter annihilation cross section assuming a spatially-extended dark matter profile consistent with dynamical modeling of the Smith Cloud. Notably, these limits exclude the canonical thermal relic cross section (∌3×10−26cm3s−1\sim 3\times10^{-26}{\rm cm}^{3}{\rm s}^{-1}) for dark matter masses â‰Č30\lesssim 30 GeV annihilating via the bbˉb \bar b or τ+τ−\tau^{+}\tau^{-} channels for certain assumptions of the dark matter density profile; however, uncertainties in the dark matter content of the Smith Cloud may significantly weaken these constraints.Comment: 7 pages, 5 figures. Published in Ap

    She is not a beauty even when she smiles: Possible evolutionary basis for a relationship between facial attractiveness and hemispheric specialization

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    The asymmetrical status of facial beauty has rarely been investigated. We studied positive facial characteristics, attractiveness and smiling, through the use of left-left and right-right composites of unfamiliar faces of women and men with natural expressions. Results showed that women's right-right composites were judged significantly more attractive than left-left composites while there was no left-right difference in men's composites (Experiment 1). On the other hand, left-left composites were judged to have more pronounced smiling expressions than right-right composites in both women's and men's faces (Experiment 2). The results confirm previous findings for leftward facial expressiveness and show for the first time asymmetry in facial attractiveness and a difference in its manifestation in women's and men's faces. The findings have biological implications for the relationship between the appearance of the sides of the face and hemispheric specialization. The organization of beauty in the human face may have been shaped by evolutionary pressures on facial asymmetries, especially as they pertain to mate selection

    EarthN: A new Earth System Nitrogen Model

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    The amount of nitrogen in the atmosphere, oceans, crust, and mantle have important ramifications for Earth's biologic and geologic history. Despite this importance, the history and cycling of nitrogen in the Earth system is poorly constrained over time. For example, various models and proxies contrastingly support atmospheric mass stasis, net outgassing, or net ingassing over time. In addition, the amount available to and processing of nitrogen by organisms is intricately linked with and provides feedbacks on oxygen and nutrient cycles. To investigate the Earth system nitrogen cycle over geologic history, we have constructed a new nitrogen cycle model: EarthN. This model is driven by mantle cooling, links biologic nitrogen cycling to phosphate and oxygen, and incorporates geologic and biologic fluxes. Model output is consistent with large (2-4x) changes in atmospheric mass over time, typically indicating atmospheric drawdown and nitrogen sequestration into the mantle and continental crust. Critical controls on nitrogen distribution include mantle cooling history, weathering, and the total Bulk Silicate Earth+atmosphere nitrogen budget. Linking the nitrogen cycle to phosphorous and oxygen levels, instead of carbon as has been previously done, provides new and more dynamic insight into the history of nitrogen on the planet.Comment: 36 pages, 12 figure
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