43,783 research outputs found

    Images of the Origin of Mass

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    Recent years have brought considerable progress with studies of the bound-state problem in continuum QCD. A small part of that made with Dyson Schwinger equations is highlighted herein. Topics covered include: opportunities provided by precision experimental studies of the (far) valence region; and capitalising upon new data on hadron elastic and transition form factors.Comment: 7 pages, 3 figures. Contribution to the Proceedings of MENU 2013 - 13th International Conference on Meson-Nucleon Physics and the Structure of the Nucleon, Rome, 30 Sept. - 4. Oct. 201

    Measured Progress: A Report on the High School Reform Movement

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    New studies on the impact of the wide-ranging efforts over the past half-decade to reform the nation's public high schools have produced important -- and encouraging -- findings

    Confinement, Diquarks and Goldstone's theorem

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    Determinations of the gluon propagator in the continuum and in lattice simulations are compared. A systematic truncation procedure for the quark Dyson-Schwinger and bound state Bethe-Salpeter equations is described. The procedure ensures the flavour-octet axial-vector Ward identity is satisfied order-by-order, thereby guaranteeing the preservation of Goldstone's theorem; and identifies a mechanism that simultaneously ensures the absence of diquarks in QCD and their presence in QCDNc=2^{N_c=2}, where the colour singlet diquark is the ``baryon'' of the theory.Comment: 7 pages, LaTeX, uses sprocl.sty and epsfig, contribution to the proceedings of ``Quark Confinement and the Hadron Spectrum'

    Wind dynamic range video camera

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    A television camera apparatus is disclosed in which bright objects are attenuated to fit within the dynamic range of the system, while dim objects are not. The apparatus receives linearly polarized light from an object scene, the light being passed by a beam splitter and focused on the output plane of a liquid crystal light valve. The light valve is oriented such that, with no excitation from the cathode ray tube, all light is rotated 90 deg and focused on the input plane of the video sensor. The light is then converted to an electrical signal, which is amplified and used to excite the CRT. The resulting image is collected and focused by a lens onto the light valve which rotates the polarization vector of the light to an extent proportional to the light intensity from the CRT. The overall effect is to selectively attenuate the image pattern focused on the sensor

    Movin' It and Improvin' It!: Using Both Education Strategies to Increase Teaching Effectiveness

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    Calls for reforms that use evaluations not only to recruit, retain, and dismiss teachers but also to enhance effectiveness through professional development. Recommends investing in proven professional development models and ensuring feedback is valuable
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