4,457 research outputs found

    Inside the Mathematics class. Sociological perspectives on participation, inclusion, and enhancement

    Get PDF
    Resenya de: Gellert, U., Knipping, C., & Straehler-Pohl, H. (2018). Inside the Mathematics Class. Sociological Perspectives on Participation, Inclusion, and Enhancement. Cham: Springer

    Experimental evidence for the essential identity of the selective and normal photo-electric effects

    Get PDF
    In the fall of 1913, while studying the photo-electric properties of freshly cut surfaces of the alkali metals in extreme vacua, we observed that immediately after first cutting, the fresh surface of sodium showed very large photo-sensitiveness when tested with monochromatic light of wave length 5461 A., even when the vacuum was of the order 10(-6) mm. as measured by a McLeod gauge. But after several weeks of experimenting and many cuttings a condition was reached in which a freshly cut surface was completely insensitive when illuminated with this wave length. The lost sensitiveness reappeared, however, in the course of not more than two minutes after cutting, and grew rapidly to a very large value in fifteen or twenty minutes. When the gas pressure was of the order of 0.01 mm. the same phenomenon occurred but the rise to a maximum value was less rapid. From these results we began to surmise that photo-electric currents must be due to the influence of some active gas, which diffused from the walls to the metal and whose action upon the surface was retarded by the presence of an inert gas

    Limits for an inverse bremsstrahlung origin of the diffuse Galactic soft gamma-ray emission

    Get PDF
    RXTE, GINGA, and OSSE observations have revealed an intense low-energy gamma-ray continuum emission from the Galactic plane, which is commonly interpreted as evidence for the possible existence of a strong flux of low-energy cosmic ray electrons. In this paper I discuss the scenario of a hadronic origin of the soft Galactic gamma-ray continuum through inverse bremsstrahlung. A flux of low-energy cosmic rays strong enough to produce the observed spectrum of gamma-rays implies substantial gamma-ray emission at a few MeV through nuclear de-excitation. It is shown that the existing limits on excess 3-7 MeV emission from the Galactic plane, in concert with the constraints from pion-decay gamma-ray emission at higher energies, are in serious conflict with an inverse bremsstrahlung origin of the Galactic soft gamma-ray emission for any physically plausible low-energy cosmic ray spectrum. While in case of energetic heavy nuclei the limits are violated by about an order of magnitude, for a large population of low-energy protons the implied gamma-ray line flux and pion-decay continuum intensity are larger than the existing limits by at least a factor of 2.Comment: 4 pages, accepted for publication in A&

    The Focal Account: Indirect Lie Detection Need Not Access Unconscious, Implicit Knowledge

    Get PDF
    People are poor lie detectors, but accuracy can be improved by making the judgment indirectly. In a typical demonstration, participants are not told that the experiment is about deception at all. Instead, they judge whether the speaker appears, say, tense or not. Surprisingly, these indirect judgments better reflect the speaker’s veracity. A common explanation is that participants have an implicit awareness of deceptive behavior, even when they cannot explicitly identify it. We propose an alternative explanation. Attending to a range of behaviors, as explicit raters do, can lead to conflict: A speaker may be thinking hard (indicating deception) but not tense (indicating honesty). In 2 experiments, we show that the judgment (and in turn the correct classification rate) is the result of attending to a single behavior, as indirect raters are instructed to do. Indirect lie detection does not access implicit knowledge, but simply focuses the perceiver on more useful cues

    [Rezension zu:] Tübinger Abhandlungen zum öffentlichen Recht. Herausgegeben von Hegler, v. Koehler, Pohl, Sartorius, Schötensack. Verlag Enke, Stuttgart. 1925

    Get PDF
    Rezension zu: Tübinger Abhandlungen zum öffentlichen Recht. Herausgegeben von Hegler, v. Koehler, Pohl, Sartorius, Schötensack. Verlag Enke, Stuttgart. 1925. 1. Heft [1924] und 2. Heft [1924

    Study of Scalar Top Quarks in the Neutralino and Chargino Decay Channel

    Get PDF
    The scalar top discovery potential has been studied with a full-statistics background simulation at sqrt(s)=500 GeV and L = 500 fb-1 for the TESLA project. The beam polarization is very important to measure the scalar top mixing angle and to determine its mass. The latest estimation of the beam polarization parameters is applied. This study includes e+ polarization, which improves the sensitivity. For a 180 GeV scalar top at minimum production cross section, we obtain delta(m) = 0.8 GeV and delta(cosT) = 0.008 in the neutralino decay channel, and delta(m) = 0.5 GeV and delta(cosT) = 0.004 in the chargino decay channel.Comment: 4 pages, 6 figures, Proc. LCWS Chicago, November 200

    The Genus Asclepias in Iowa

    Get PDF
    The present study was undertaken to provide modern distribution maps and a workable key for the Iowa milkweeds. The genus Asclepias has not been separately studied in Iowa, so far as\u27\u27 the authors can ascertain. In the most recent Iowa flora, Conard (1951) lists 16 species. In the present work 15 species are recognized. Appreciation is extended to Dr. Robert Thorne and Dr. Richard Pohl for the use of specimens from the herbaria of the State University of Iowa and Iowa State College. In addition, material from the herbarium of Grinnell College has been studied. In all, approximately 1200 sheets of Asclepias were examined

    Critical Issues: Defining and Debunking Misconceptions in Health, Education, Criminal Justice, and Social Work/Social Services

    Get PDF
    The University of Houston Downtown Committee for the Journal of Family Strengths introduces Volume 18, Issue 1: Critical Issues: Defining and Debunking Misconceptions in Health, Education, Criminal Justice, and Social Work/Social Services
    • …
    corecore