4,667 research outputs found

    Whites' perceptions of biracial individuals' race shift when biracials speak out against bias

    Get PDF
    Previous research suggests that a person’s racial identity shapes the way others respond when that person speaks out against racial prejudice. In the present research, we consider instead how speaking out against racial prejudice shapes people’s impressions of a confronter’s racial identity, such as experiences with discrimination, stereotype enactment, and even phenotype. Two experiments found that White perceivers evaluated a Black/White biracial person who spoke out against (versus remained silent to) racial prejudice as more stigmatized and Black-identified, and as having more stereotypically Black (vs. White) preferences and Black (vs. White) ancestry when they confronted. The faces of biracial confronters (vs. non-confronters) were also recalled as more phenotypically Black (vs. White; Study 2). This evidence suggests that speaking out against bias colors Whites’ impressions of a biracial target across both subjective and objective measures of racial identity. Implications for interracial interactions and interpersonal perception are discussed

    A 10B-based neutron detector with stacked Multiwire Proportional Counters and macrostructured cathodes

    Full text link
    We present the results of the measurements of the detection efficiency for a 4.7 \r{A} neutron beam incident upon a detector incorporating a stack of up to five MultiWire Proportional Counters (MWPC) with Boron-coated cathodes. The cathodes were made of Aluminum and had a surface exhibiting millimeter-deep V-shaped grooves of 45{\deg}, upon which the thin Boron film was deposited by DC magnetron sputtering. The incident neutrons interacting with the converter layer deposited on the sidewalls of the grooves have a higher capture probability, owing to the larger effective absorption film thickness. This leads to a higher overall detection efficiency for the grooved cathode when compared to a cathode with a flat surface. Both the experimental results and the predictions of the GEANT4 model suggests that a 5-counter detector stack with coated grooved cathodes has the same efficiency as a 7-counter stack with flat cathodes. The reduction in the number of counters in the stack without altering the detection efficiency will prove highly beneficial for large-area position-sensitive detectors for neutron scattering applications, for which the cost-effective manufacturing of the detector and associated readout electronics is an important objective. The proposed detector concept could be a technological option for one of the new chopper spectrometers and other instruments planned to be built at the future European Spallation Source in Sweden. These results with macrostructured cathodes generally apply not just to MWPCs but to other gaseous detectors as well.Comment: 14 pages, 9 figure

    Boron-10 lined RPCs for sub-millimeter resolution thermal neutron detectors: Feasibility study in a thermal neutron beam

    Full text link
    The results of an experimental feasibility study of a position sensitive thermal neutron detector based on a resistive plate chamber (RPC) are presented. The detector prototype features a thin-gap (0.35 mm) hybrid RPC with an aluminium cathode lined with a 2 μ{\mu}m thick 10B4C^{10}B{_4}C neutron converter layer enriched in 10B^{10}B and a float glass anode. A detection efficiency of {\approx} 6.2 %{\%} was measured for the neutron beam (λ{\lambda} =2.5 A˚{\AA}) at normal incidence. A spatial resolution better than 0.5 mm FWHM was demonstrated

    Effects of High Charge Densities in Multi-GEM Detectors

    Full text link
    A comprehensive study, supported by systematic measurements and numerical computations, of the intrinsic limits of multi-GEM detectors when exposed to very high particle fluxes or operated at very large gains is presented. The observed variations of the gain, of the ion back-flow, and of the pulse height spectra are explained in terms of the effects of the spatial distribution of positive ions and their movement throughout the amplification structure. The intrinsic dynamic character of the processes involved imposes the use of a non-standard simulation tool for the interpretation of the measurements. Computations done with a Finite Element Analysis software reproduce the observed behaviour of the detector. The impact of this detailed description of the detector in extreme conditions is multiple: it clarifies some detector behaviours already observed, it helps in defining intrinsic limits of the GEM technology, and it suggests ways to extend them.Comment: 5 pages, 6 figures, 2015 IEEE Nuclear Science Symposiu

    Neutrality of narrative discussion in annual reports of UK listed companies

    Get PDF
    This paper reports the results of an investigation into the neutrality of the narrative discussion of financial performance and position, as evidenced in 179 annual reports of UK listed companies. Neutrality of narrative discussion was determined by comparing the average proportions of good and bad news contained in the narrative and statutory accounts sections of the annual reports. The results of a comparison of the proportion of good news in the two sections of the annual reports suggest that the narrative sections contained a significantly higher proportion of good news than the statutory accounts sections. Comparison of proportions of bad news, however, indicates that the narrative sections contained a significantly lower proportion of bad news compared to the statutory accounts sections. Finally, the results also suggest that the proportion of good news as compared to bad news in the narrative sections is significantly higher than the proportion of good news compared to bad news in the statutory accounts section. The results are consistent with the suggestion that company management highlights good news in narrative discussions. The implications of the findings for company management, users, auditors and regulators are discussed

    u-RANIA: a neutron detector based on \mu -RWELL technology

    Full text link
    In the framework of the ATTRACT-uRANIA project, funded by the European Community, we are developing an innovative neutron imaging detector based on micro-Resistive WELL (μ\mu -RWELL) technology. The μ\mu -RWELL, based on the resistive detector concept, ensuring an efficient spark quenching mechanism, is a highly reliable device. It is composed by two main elements: a readout-PCB and a cathode. The amplification stage for this device is embedded in the readout board through a resistive layer realized by means of an industrial process with DLC (Diamond-Like Carbon). A thin layer of B4_4C on the copper surface of the cathode allows the thermal neutrons detection through the release of 7^7Li and α\alpha particles in the active volume. This technology has been developed to be an efficient and convenient alternative to the 3^3He shortage. The goal of the project is to prove the feasibility of such a novel neutron detector by developing and testing small planar prototypes with readout boards suitably segmented with strip or pad read out, equipped with existing electronics or readout in current mode. Preliminary results from the test with different prototypes, showing a good agreement with the simulation, will be presented together with construction details of the prototypes and the future steps of the project.Comment: Prepared for the INSTR20 Conference Proceeding for JINS

    Ion Mobility-Mass Spectrometry with a Radial Opposed Migration Ion and Aerosol Classifier (ROMIAC)

    Get PDF
    The first application of a novel differential mobility analyzer, the radial opposed migration ion and aerosol classifier (ROMIAC), is demonstrated. The ROMIAC uses antiparallel forces from an electric field and a cross-flow gas to both scan ion mobilities and continuously transmit target mobility ions with 100% duty cycle. In the ROMIAC, diffusive losses are minimized, and resolution of ions, with collisional cross-sections of 200–2000 Å^2, is achieved near the nondispersive resolution of ~20. Higher resolution is theoretically possible with greater cross-flow rates. The ROMIAC was coupled to a linear trap quadrupole mass spectrometer and used to classify electrosprayed C2–C12 tetra-alkyl ammonium ions, bradykinin, angiotensin I, angiotensin II, bovine ubiquitin, and two pairs of model peptide isomers. Instrument and mobility calibrations of the ROMIAC show that it exhibits linear responses to changes in electrode potential, making the ROMIAC suitable for mobility and cross-section measurements. The high resolution of the ROMIAC facilitates separation of isobaric isomeric peptides. Monitoring distinct dissociation pathways associated with peptide isomers fully resolves overlapping peaks in the ion mobility data. The ability of the ROMIAC to operate at atmospheric pressure and serve as a front-end analyzer to continuously transmit ions with a particular mobility facilitates extensive studies of target molecules using a variety of mass spectrometric methods

    A century of variation in the dependence of Greenland iceberg calving on ice sheet surface mass balance and regional climate change

    Get PDF
    Iceberg calving is a major component of the total mass balance of the Greenland ice sheet (GrIS). A century-long record of Greenland icebergs comes from the International Ice Patrol's record of icebergs (I48N) passing latitude 48° N, off Newfoundland. I48N exhibits strong interannual variability, with a significant increase in amplitude over recent decades. In this study, we show, through a combination of nonlinear system identification and coupled ocean-iceberg modelling, that I48N's variability is predominantly caused by fluctuation in GrIS calving discharge rather than open ocean iceberg melting. We also demonstrate that the episodic variation in iceberg discharge is strongly linked to a nonlinear combination of recent changes in the surface mass balance (SMB) of the GrIS and regional atmospheric and oceanic climate variability, on the scale of the previous 1-3 years, with the dominant causal mechanism shifting between glaciological (SMB) and climatic (ocean temperature) over time. We suggest that this is a change in whether glacial run-off or under-ice melting is dominant, respectively. We also suggest that GrIS calving discharge is episodic on at least a regional scale and has recently been increasing significantly, largely as a result of west Greenland sources. © 2014 The Author(s) Published by the Royal Society. All rights reserved

    Charge Transfer Properties Through Graphene Layers in Gas Detectors

    Full text link
    Graphene is a single layer of carbon atoms arranged in a honeycomb lattice with remarkable mechanical, electrical and optical properties. For the first time graphene layers suspended on copper meshes were installed into a gas detector equipped with a gaseous electron multiplier. Measurements of low energy electron and ion transfer through graphene were conducted. In this paper we describe the sample preparation for suspended graphene layers, the testing procedures and we discuss the preliminary results followed by a prospect of further applications.Comment: 2014 IEEE Nuclear Science Symposium and Medical Imaging Conference with the 21st Symposium on Room-Temperature Semiconductor X-Ray and Gamma-Ray Detectors, 4 pages, 8 figure

    What’s sex got to do with it? A family-based investigation of growing up heterosexual during the twentieth century

    Get PDF
    This paper explores findings from a cross-generational study of the making of heterosexual relationships in East Yorkshire, which has interviewed women and men within extended families. Using a feminist perspective, it examines the relationship between heterosexuality and adulthood, focussing on sexual attraction, courtship, first kisses, first love and first sex, as mediated within family relationships, and at different historical moments. In this way, the contemporary experiences of young people growing up are compared and contrasted with those of mid-lifers and older adults who formed heterosexual relationships within the context of the changing social and sexual mores of the 1960s/1970s, and the upheavals of World War Two
    corecore