191 research outputs found

    “Not one of us”: predictors and consequences of denying ingroup characteristics to ambiguous targets

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    We investigated individual difference predictors of ascribing ingroup characteristics to negative and positive ambiguous targets. Studies 1 and 2 investigated events involving negative targets whose status as racial (Tsarnaev brothers) or national (Woolwich attackers) ingroup members remained ambiguous. Immediately following the attacks, we presented White Americans and British individuals with the suspects’ images. Those higher in social dominance orientation (SDO) and right-wing authoritarianism (RWA)—concerned with enforcing status boundaries and adherence to ingroup norms, respectively—perceived these low status and low conformity suspects as looking less White and less British, thus denying them ingroup characteristics. Perceiving suspects in more exclusionary terms increased support for treating them harshly, and for militaristic counter-terrorism policies prioritizing ingroup safety over outgroup harm. Studies 3 and 4 experimentally manipulated a racially ambiguous target’s status and conformity. Results suggested that target status and conformity critically influence SDO’s (status) and RWA’s (conformity) effects on inclusionary versus exclusionary perceptions

    Thermal performance of a controllable pavement solar collector prototype with configuration flexibility

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    Solar energy harvesting as a renewable and sustainable energy source has been widely investigated in recent years across engineering fields. The use of Pavement Solar Collectors (PSC) can lead to clean energy production, an increase in road safety, prolong the service life of asphalt pavement, and can mitigate the Urban Heat Island (UHI) effect. This study describes a controllable large-scale research PSC prototype with high configuration flexibility, and full monitoring capability at the University of Antwerp, Belgium. Since small- or laboratory-scale setups do not reflect the behavior of actual projects, the present paper investigates the thermal response of a large-scale PSC in the Western European climate, including heating load, heat extraction capacity, and asphalt surface and profile temperature changes during heating and cooling experiments. The study shows that a low supply temperature compared to high (14 °C vs. 28 °C) can reduce the depletion rate of the stored thermal energy in borehole thermal energy storage up to 7 times. The sensitivity analysis indicates that an increase in flow rate from laminar to transient regime requires twice as much thermal power compared to the same flow rate changes within transient and turbulent regimes. The maximum average daily efficiency of the PSC could reach 34% with a flow rate of 4 l/min. The experimental results showed that increasing the pipe length from 50 m to 200 m reduces the cumulative power extraction capacity by up to 48%. Furthermore, the PSC system shows great potential in reducing the asphalt surface temperature (up to 12 °C) to mitigate the UHI effects. Finally, the PSC system effectively controls the temperatures of the interface zones to reduce the rutting distress in the summertime and lower the potential of cold thermal crack developments and brittle shear failure behavior in wintertime

    Diffuse Galactic light at high Galactic latitude: nature and interpretation

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    The hypothesis of an extended red emission (ERE) in diffuse Galactic light (DGL) has been put forward in 1998 by Gordon, Witt and Friedmann who found that scattered starlight was not enough to explain the amount of DGL in the R band, in some high Galactic latitude directions. This paper re-investigates, for high Galactic latitudes, the brightnesses and colours of DGL, integrated star and galaxy light (ISGL), and of the total extrasolar light (ISGL+DGL) measured by Pioneer. Under the traditional assumption that DGL is forward scattering of background starlight by interstellar dust on the line of sight, ISGL and Pioneer have very close colours, as it is found by Gordon, Witt and Friedmann. Pioneer observations at high |b| thus accept an alternative and simple interpretation, with no involvement of ERE in DGL.Comment: 9 pages, 5 figure

    Dwarf elliptical galaxies in Centaurus A group: stellar populations in AM 1339-445 and AM 1343-452

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    We study the red giant populations of two dE galaxies, AM 1339-445 and AM 1343-452, with the aim of investigating the number and luminosity of any upper asymptotic giant branch (AGB) stars present. The galaxies are members of the Centaurus A group (D~3.8 Mpc) and are classified as outlying (R~350 kpc) satellites of Cen A. The analysis is based on near-IR photometry for individual red giant stars, derived from images obtained with ISAAC on the VLT. The photometry, along with optical data derived from WFPC2 images retrieved from the HST science archive, enable us to investigate the stellar populations of the dEs in the vicinity of the red giant branch (RGB) tip. In both systems we find stars above the RGB tip, which we interpret as intermediate-age upper-AGB stars. The presence of such stars is indicative of extended star formation in these dEs similar to that seen in many, but not all, dEs in the Local Group. For AM 1339-445, the brightest of the upper-AGB stars have Mbol~-4.5 while those in AM 1343-452 have Mbol~-4.8 mag. These luminosities suggest ages of approximately 6.5+/-1 and 4+/-1 Gyr as estimates for the epoch of the last episode of significant star formation in these systems. In both cases the number of upper-AGB stars suggests that ~15% of the total stellar population is in the form of intermediate-age stars, considerably less than is the case for outlying dE satellites of the Milky Way such as Fornax and LeoI.Comment: 18 pages, 19 figures, A&A accepted; high resolution version available from: http://www.eso.org/~mrejkuba/CenA_dEs_I.pd

    Globular cluster system and Milky Way properties revisited

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    Updated data of the 153 Galactic globular clusters are used to readdress fundamental parameters of the Milky Way. We build a reduced sample, decontaminated of the clusters younger than 10Gyr, those with retrograde orbits and/or evidence of relation to dwarf galaxies. The 33 metal-rich globular clusters of the reduced sample extend basically to the Solar circle and distribute over a region with projected axial-ratios typical of an oblate spheroidal, Δx:Δy:Δz1.0:0.9:0.4\rm\Delta x:\Delta y:\Delta z\approx1.0:0.9:0.4. The 81 metal-poor globular clusters span a nearly spherical region of axial-ratios 1.0:1.0:0.8\approx1.0:1.0:0.8 extending from the central parts to the outer halo. A new estimate of the Sun's distance to the Galactic center is provided, RO=7.2±0.3kpc\rm R_O=7.2\pm0.3 kpc. The metal-rich and metal-poor radial-density distributions flatten for RGC2kpc\rm R_{GC}\leq2 kpc and are well represented both by a power-law with a core-like term and S\'ersic's law; at large distances they fall off as R3.9\rm\sim R^{-3.9}. Both metallicity components appear to have a common origin, which is different from that of the dark matter halo. Structural similarities of the metal-rich and metal-poor radial distributions with the stellar halo are consistent with a scenario where part of the reduced sample was formed in the primordial collapse, and part was accreted in an early period of merging. This applies to the bulge as well, suggesting an early merger affecting the central parts of the Galaxy. We estimate that the present globular cluster population corresponds to 23±6\rm\leq23\pm6% of the original one. The fact that the volume-density radial distributions of the metal-rich and metal-poor globular clusters of the reduced sample follow both a core-like power-law and S\'ersic's law indicates that we are dealing with spheroidal subsystems in all scales.Comment: 14 pages and 6 figures. Astronomy & Astrophysics, accepted on NOv. 2

    The Nature of Islamophobia: A Test of a Tripartite View in Five Countries.

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    Funder: Excellence Initiative of the states and the federal government (German Research Foundation)This article provides an examination of the structure of Islamophobia across cultures. Our novel measure-the Tripartite Islamophobia Scale (TIS)-embeds three theoretically and statistically grounded subcomponents of Islamophobia: anti-Muslim prejudice, anti-Islamic sentiment, and conspiracy beliefs. Across six samples (i.e., India, Poland, Germany, France, and the United States), preregistered analyses corroborated that these three subcomponents are statistically distinct. Measurement invariance analyses indicated full scalar invariance, suggesting that the tripartite understanding of Islamophobia is generalizable across cultural contexts. Furthermore, the subcomponents were partially dissociated in terms of the intergroup emotions they are predicted by as well as the intergroup outcomes they predict (e.g., dehumanization, ethnic persecution). For example, intergroup anger and disgust underpin Islamophobic attitudes, over and above the impact of fear. Finally, our results show that social dominance orientation (SDO) and ingroup identification moderate intergroup emotions and Islamophobia. We address both theoretical implications for the nature of Islamophobia and practical interventions to reduce it

    The distance of M33 and the stellar population in its outskirts

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    We present deep V,I photometry of two $9.4' x 9.4' field in the outer regions of the M33 galaxy. We obtain a robust detection of the luminosity of the Red Giant Branch Tip (I{TRGB}=20.72 +- 0.08) from which we derived a new estimate of the distance modulus of M33, (m-M)_0=24.64 +- 0.15, corresponding to a distance D=847 +- 60 Kpc. By comparison of the color and magnitude of the observed Red Giant Branch stars with ridge lines of template globular clusters we obtained the photometric metallicity distribution of the considered fields in three different metallicity scales. The derived metallicity distributions are very similar over a range of distances from the galactic center 10' <= R <= 33', and are characterized by a well defined peak at [M/H] ~ -0.7 ([Fe/H] ~ -1.0, in the Zinn & West scale) and a weak metal-poor tail reaching [M/H] ~ -2.0. Our observations demonstrate that Red Giant Branch and Asymptotic Giant Branch stars have a radial distribution that is much more extended than the young MS stars associated with the star-forming disc.Comment: 10 pages,10 figures,accepted for publication in Astronomy & Astrophysic
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