1,195 research outputs found

    "Girl You Better Apply to Teachers' College": The History of Black Women Educators in Ontario, 1940s - 1980s

    Get PDF
    Girl You Better Apply to Teachers College examines the role of black women educators in Ontario from the 1940s to the 1980s. In an attempt to contribute to historical analysis on black identity, citizenship and racial difference in Canada, this dissertation investigates the ways in which black Canadian women confronted and navigated socially constructed boundaries of racial alienation, limited institutional support and inequality within Ontario school systems. In post-World War II Canada, black womens experiences in the teaching profession served as sites of struggle and contestation in a myriad of ways. Their presence as racialized educators, though smaller in number, represented the various ways in which black women disrupted mainstream notions of education in Ontario and challenged Canadian nationhood more broadly. This dissertation project argues that black women teachers engagement with Ontarios education system was comprised of a set of difficult, messy and complex processes; beginning with access to education, their ability to get into teachers college, the constant questioning of their professional status and the material realities that shaped their choices inside Ontario schools, black women teachers worked to prove their legitimacy and dedication to the vocation. At a time when education was used to teach young pupils how to be good moral citizens, black womens presence within these schooling institutions served to challenge the ways in which education was imparted and also revealed a system ill-equipped to deal with its changing student population. Largely using oral interviews, school board minutes, newspapers, yearbooks, and community records, Girl You Better Apply to Teachers College argues that black women educators sense of belonging in the professional sphere circumvented subtle and overt forms of racial and social exclusion in Ontario schools. In an effort to locate themselves within the Canadian national narrative, black female educators navigated concepts of citizenship and created a new kind of belonging that was parallel to and, at times, intersected with concepts of Canadian statehood

    Greece’s Three-Act Tragedy:A Simple Model of Grexit vs. Staying Afloat inside the Single Currency Area

    Get PDF
    Against the backdrop of the Greek three-act tragedy, we present a theoretical framework for studying Greece’s recent debt and currency crisis. The model is built on two essential blocks: first, erratic macroeconomic policymaking in Greece is described using a stochastic regimeswitching model; second, the euro area governments’ responses to uncertain macroeconomic policies in Greece are considered. The model’s mechanism and assumptions allow either for a Grexit from the euro area or, conversely, the avoidance of Greece’s default against its creditors. The model also offers useful guidance to understand key drivers of the long-winded negotiations between the Syiza government and the euro area governments

    Life Beyond the Solar System: Space Weather and Its Impact on Habitable Worlds

    Get PDF
    The search of life in the Universe is a fundamental problem of astrobiology and a major priority for NASA. A key area of major progress since the NASA Astrobiology Strategy 2015 (NAS15) has been a shift from the exoplanet discovery phase to a phase of characterization and modeling of the physics and chemistry of exoplanetary atmospheres, and the development of observational strategies for the search for life in the Universe by combining expertise from four NASA science disciplines including heliophysics, astrophysics, planetary science and Earth science. The NASA Nexus for Exoplanetary System Science (NExSS) has provided an efficient environment for such interdisciplinary studies. Solar flares, coronal mass ejections and solar energetic particles produce disturbances in interplanetary space collectively referred to as space weather, which interacts with the Earth upper atmosphere and causes dramatic impact on space and ground-based technological systems. Exoplanets within close in habitable zones around M dwarfs and other active stars are exposed to extreme ionizing radiation fluxes, thus making exoplanetary space weather (ESW) effects a crucial factor of habitability. In this paper, we describe the recent developments and provide recommendations in this interdisciplinary effort with the focus on the impacts of ESW on habitability, and the prospects for future progress in searching for signs of life in the Universe as the outcome of the NExSS workshop held in Nov 29 - Dec 2, 2016, New Orleans, LA. This is one of five Life Beyond the Solar System white papers submitted by NExSS to the National Academy of Sciences in support of the Astrobiology Science Strategy for the Search for Life in the Universe.Comment: 5 pages, the white paper was submitted to the National Academy of Sciences in support of the Astrobiology Science Strategy for the Search for Life in the Univers

    TRAUMA AND STRESSOR-RELATED DISORDERS AMONG INTERNALLY DISPLACED PERSONS IN THE FEDERAL CAPITAL TERRITORY, ABUJA

    Get PDF
    This paper assesses stress and trauma-related disorders among the Internally Displaced Persons in the Federal Capital Territory, Abuja, Nigeria. In its methodology, the study took a descriptive approach. A convenient sample of 300 participants were drawn from each of the four officially recognized camps in the FCT making a total sample of 900 participants for this study. Face-face interview was conducted using interviewer administered structured questionnaire. Two additional research assistants and two Hausa interpreters were recruited for this study. The response rate was 100 percent. Anxiety, adjustment and attachment disorders were most prevalent in this study. Traumatic stress disorders were higher in respondents aged 37-58, and the unemployed. The interview was face-face and psychological tools like PHQ-9, PHQ-GAD, PHQ-SADS were used. Findings showed that a large proportion of the respondents are less educated, 94% of respondents were unemployed as at the time of this study. (67%) and those separated from spouses and family as a result of Boko-harm attacks. Recommendation made was that getting timely help and support may prevent normal stress reactions from getting worse and developing into PTS

    High statistics study of the reaction γpp  2π0\gamma p\to p\;2\pi^0

    Get PDF
    The photoproduction of 2π0\pi^0 mesons off protons was studied with the Crystal Barrel/TAPS experiment at the electron accelerator ELSA in Bonn. The energy of photons produced in a radiator was tagged in the energy range from 600\,MeV to 2.5\,GeV. Differential and total cross sections and pπ0π0p\pi^0\pi^0 Dalitz plots are presented. Part of the data was taken with a diamond radiator producing linearly polarized photons, and beam asymmetries were derived. Properties of nucleon and Δ\Delta resonances contributing to the pπ0π0p\pi^0\pi^0 final state were determined within the BnGa partial wave analysis. The data presented here allow us to determine branching ratios of nucleon and Δ\Delta resonances for their decays into pπ0π0p\pi^0\pi^0 via several intermediate states. Most prominent are decays proceeding via Δ(1232)π\Delta(1232)\pi, N(1440)1/2+πN(1440)1/2^+\pi, N(1520)3/2πN(1520)3/2^-\pi, N(1680)5/2+πN(1680)5/2^+\pi, but also pf0(500)pf_0(500), pf0(980)pf_0(980), and pf2(1270)pf_2(1270) contribute to the reaction.Comment: 28 pages, 17 figures, 7 table

    Photoproduction of pi0 omega off protons for E(gamma) < 3 GeV

    Full text link
    Differential and total cross-sections for photoproduction of gamma proton to proton pi0 omega and gamma proton to Delta+ omega were determined from measurements of the CB-ELSA experiment, performed at the electron accelerator ELSA in Bonn. The measurements covered the photon energy range from the production threshold up to 3GeV.Comment: 8 pages, 13 figure

    Modification of the ω\omega-Meson Lifetime in Nuclear Matter

    Full text link
    The photo production of ω\omega mesons on the nuclei C, Ca, Nb and Pb has been measured using the Crystal Barrel/TAPS detector at the ELSA tagged photon facility in Bonn. The dependence of the ω\omega meson cross section on the nuclear mass number has been compared with three different types of models, a Glauber analysis, a BUU analysis of the Giessen theory group and a calculation by the Valencia theory group. In all three cases, the inelastic ω\omega width is found to be 130150MeV/c2130-150 \rm{MeV/c^2} at normal nuclear matter density for an average 3-momentum of 1.1 GeV/c. In the restframe of the ω\omega meson, this inelastic ω\omega width corresponds to a reduction of the ω\omega lifetime by a factor 30\approx 30. For the first time, the momentum dependent ω\omegaN cross section has been extracted from the experiment and is in the range of 70 mb.Comment: 5 pages, 4 figure

    Photoproduction of meson pairs: First measurement of the polarization observable I^s

    Get PDF
    The polarization observable I^s, a feature exclusive to the acoplanar kinematics of multi-meson final states produced via linearly polarized photons, has been measured for the first time. Results for the reaction g p -> p pi0 eta are presented for incoming photon energies between 970 MeV and 1650 MeV along with the beam asymmetry I^c. The comparably large asymmetries demonstrate a high sensitivity of I^s to the dynamics of the reaction. Fits using Bonn-Gatchina partial wave analysis demonstrate that the new polarization observables carry significant information on the contributing partial waves.Comment: 11 pages, 6 figures, v2 to appear in Phys. Lett.

    In-medium ω\omega mass from the γ+Nbπ0γ+X\gamma + Nb \to \pi^{0}\gamma + X reaction

    Full text link
    Data on the photoproduction of ω\omega mesons on nuclei have been re-analyzed in a search for in-medium modifications. The data were taken with the Crystal Barrel(CB)/TAPS detector system at the ELSA accelerator facility in Bonn. First results from the analysis of the data set were published by D. Trnka et al. in Phys. Rev. Lett 94 (2005) 192303 \cite{david}, claiming a lowering of the ω\omega mass in the nuclear medium by 14% at normal nuclear matter density. The extracted ω\omega line shape was found to be sensitive to the background subtraction. For this reason a re-analysis of the same data set has been initiated and a new method has been developed to reduce the background and to determine the shape and absolute magnitude of the background directly from the data. Details of the re-analysis and of the background determination are described. The ω\omega signal on the NbNb target, extracted in the re-analysis, does not show a deviation from the corresponding line shape on a LH2LH_2 target, measured as reference. The earlier claim of an in-medium mass shift is thus not confirmed. The sensitivity of the ω\omega line shape to different in-medium modification scenarios is discussed.Comment: 13 pages and 11 figures, submitted for publicatio

    Quasi-free photoproduction of eta-mesons of the neutron

    Full text link
    Quasi-free photoproduction of eta-mesons off nucleons bound in the deuteron has been measured with the CBELSA/TAPS detector for incident photon energies up to 2.5 GeV at the Bonn ELSA accelerator. The eta-mesons have been detected in coincidence with recoil protons and recoil neutrons, which allows a detailed comparison of the quasi-free n(gamma,eta)n and p(gamma,eta)p reactions. The excitation function for eta-production off the neutron shows a pronounced bump-like structure at W=1.68 GeV (E_g ~ 1 GeV), which is absent for the proton.Comment: accepted for publication in Phys. Rev. Let
    corecore