44,533 research outputs found
Images of the Origin of Mass
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
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
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 QCD, 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
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
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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