1,162 research outputs found

    Using IDI Guided Development to Increase Intercultural Competence

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    The qualitative case study examined Intercultural Development Inventory (IDI) pre-post test data and responses from a sample of preservice teachers. The study focused on the effect of the process of administering IDI Guided Development to increase the intercultural competence of preservice teachers. The study was based on the conceptual framework of the Intercultural Development Continuum (IDC), adapted from the Developmental Model of Intercultural Sensitivity originally proposed by Dr. Milton Bennett. In addition, intercultural competence models, theories, practices, and strategies were examined, including Deardorff’s Developing and Assessing Intercultural Competence Models, Kolb’s Experiential Learning Theory, Mezirow’s Transformative Learning Theory, Loden’s Dimensions of Diversity Wheel, and Weigl’s Cultural Self-Study. The findings of the study revealed how effective IDI Guided Development, a comprehensive five-step developmental process, combined with individualized coaching guidance by an IDI Qualified Administrator, produced impressive increases in intercultural competence development. Drawing on many educational theories and models, the study results demonstrated the importance of using a combination of a high-quality assessment tool, a transformative experiential learning process for change, measurable goals and outcomes, and a coach to facilitate the development of intercultural competence

    Laboratory Evaluation of Black Carbon Deposition onto Snow and Transport via Snowmelt

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    Black carbon (BC) is an aerosol material produced by incomplete combustion of fossil fuels and biomass. BC has been shown to be the second most important anthropogenic climate warming agent after carbon dioxide due to its ability to absorb solar radiation, influence cloud behavior, and accelerate snow melt. BC in otherwise clean snow can significantly reduce its reflectivity. In order to learn about the significance of BC contamination in snow, we explored the deposition of BC onto snow and the transport of BC in snow during snowmelt. A Single Particle Soot Photometer (SP2), was used to measure the concentration and size distribution of BC in an airstream drawn through snow to determine the rate at which the snow trapped BC. BC concentration in meltwater was measured to determine if the BC was left in the snow or was removed during melting. SP2 testing showed a significant drop in BC aerosol concentration after contact with the snow. This implies that naturally occurring snow is a highly efficient absorber of BC from the atmosphere. Meltwater samples had a lower BC concentration than the snow, suggesting that the majority of the BC is left behind in snow during partial melting. This accumulation of BC could potentially cause a positive feedback to the rate of snowmelt. Better understanding the behavior of BC in snow will help scientists describe the impact of BC on climate and help policymakers predict the benefits of reducing BC emissions

    Investigative Methods for the Science Teacher

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    The basis for this research project was the idea: Why tell or lecture students about an idea or fact when, if given the appropriate information, they would be able to figure it out for themselves? This does not mean that we hand the students a text and tell them to learn about the subject on their own, nor is this investigative approach to be used all the time. Because of the different levels of reasoning needed for various topics, one cannot expect a student to deduce the composition of an atom as easily as he can deduce the composition of granite. Some topics have more meaning if they are explained. Others, however, are more meaningful if the student discovers them. The topic of this research was to experiment and find ways in which to make certain topics investigative

    Theory of optical spectra of polar quantum wells: Temperature effects

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    Theoretical and numerical calculations of the optical absorption spectra of excitons interacting with longitudinal-optical phonons in quasi-2D polar semiconductors are presented. In II-VI semiconductor quantum wells, exciton binding energy can be tuned on- and off-resonance with the longitudinal-optical phonon energy by varying the quantum well width. A comprehensive picture of this tunning effect on the temperature-dependent exciton absorption spectrum is derived, using the exciton Green's function formalism at finite temperature. The effective exciton-phonon interaction is included in the Bethe-Salpeter equation. Numerical results are illustrated for ZnSe-based quantum wells. At low temperatures, both a single exciton peak as well as a continuum resonance state are found in the optical absorption spectra. By contrast, at high enough temperatures, a splitting of the exciton line due to the real phonon absorption processes is predicted. Possible previous experimental observations of this splitting are discussed.Comment: 10 pages, 9 figures, to appear in Phys. Rev. B. Permanent address: [email protected]

    Polyethylene imine-based receptor immobilization for label free bioassays

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    Polyethylene imine (PEI) based immobilization of antibodies is described and the concept is proved on the label free assay of C-Reactive Protein (CRP). This novel immobilization method is composed of a hyperbranched PEI layer which was deposited at a high pH (9.5) on the sensor surface. The free amino groups of PEI were derivatized with neutravidin by Biotin N-hydroxysuccinimide ester and the biotinylated anti-CRP antibody immobilized on this layer. Direct binding assay of recombinant CRP was successfully performed in the low ÎŒg/ml concentrations using a label free optical waveguide biosensor

    Skilful seasonal predictions of Summer European rainfal

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    This is the author accepted manuscript. The final version is available from American Geophysical Union (AGU) via the DOI in this record.Year-to-year variability in Northern European summer rainfall has profound societal and economic impacts; however current seasonal forecast systems show no significant forecast skill. Here we show skilful predictions are possible (r~0.5, p80 members) are required for skilful predictions. This work is promising for the development of European summer rainfall climate services.This work was supported by the Joint DECC/Defra Met Office Hadley Centre Climate Programme (GA01101), the EU FP7 SPECS project. We acknowledge the E-OBS dataset from the EU-FP6 project ENSEMBLES (http://ensembles-eu.metoffice.com) and the data providers in the ECA&D project (http://www.ecad.eu). We also would like to thank Gerard van der Schrier and Else Van Den Besselaar for kindly providing us the pre-release E-OBS dataset version 'v16e' and further support. Model data used to create the figures are available from the authors upon request for academic use

    Fine structure of excitons in Cu2_2O

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    Three experimental observations on 1s-excitons in Cu2_2O are not consistent with the picture of the exciton as a simple hydrogenic bound state: the energies of the 1s-excitons deviate from the Rydberg formula, the total exciton mass exceeds the sum of the electron and hole effective masses, and the triplet-state excitons lie above the singlet. Incorporating the band structure of the material, we calculate the corrections to this simple picture arising from the fact that the exciton Bohr radius is comparable to the lattice constant. By means of a self-consistent variational calculation of the total exciton mass as well as the ground-state energy of the singlet and the triplet-state excitons, we find excellent agreement with experiment.Comment: Revised abstract; 10 pages, revtex, 3 figures available from G. Kavoulakis, Physics Department, University of Illinois, Urban

    On the determination of the Fermi surface in high-Tc superconductors by angle-resolved photoemission spectroscopy

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    We study the normal state electronic excitations probed by angle resolved photoemission spectroscopy (ARPES) in Bi2201 and Bi2212. Our main goal is to establish explicit criteria for determining the Fermi surface from ARPES data on strongly interacting systems where sharply defined quasiparticles do not exist and the dispersion is very weak in parts of the Brillouin zone. Additional complications arise from strong matrix element variations within the zone. We present detailed results as a function of incident photon energy, and show simple experimental tests to distinguish between an intensity drop due to matrix element effects and spectral weight loss due to a Fermi crossing. We reiterate the use of polarization selection rules in disentangling the effect of umklapps due to the BiO superlattice in Bi2212. We conclude that, despite all the complications, the Fermi surface can be determined unambiguously: it is a single large hole barrel centered about (pi,pi) in both materials.Comment: Expanded discussion of symmetrization method in Section 5, figures remain the sam
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