The use of conversation mapping to frame key perceptual issues facing the general dental practice system in England

<b>Objective</b>: To demonstrate the use of a novel qualitative methodology namely conversation mapping, which can be used to capture differences in stakeholder perspectives and give a root definition of the problem in a complex policy area. The methodology is used in the context of the changes introduced in the English general dental practice system in April 2006, to investigate the key issues facing the system, as perceived by general dental practitioners (GDPs). <b>Basic research design</b>: From a broad trigger statement, three transformational statements were produced. Each participant recorded their contribution on a hard diagrammatic form as a ‘map’, with others responding with their own written comment, thus generating three conversation maps. Thematic analysis resulted in the generation of a preliminary model summarising key perceptual issues. <b>Results</b>: The five emergent themes identified were: financing, dentists’ wants/needs, the role of the public and patients, system goals and policy level decision making. Financing was identified as the core category to which all other categories were related. <b>Conclusions</b>: Conversation mapping, a methodology arising from a systems approach, can be used to develop a ‘rich picture’ of an oral health care system in order to define the core problem within this policy area. Findings suggest that GDPs identify the financing of the system as a fundamental source of problems within the general dental practice system. This appears to be at variance with the perception of policy makers, who report a more limited view, identifying the system of remuneration as the ‘heart of the problem’

Dark-State Polaritons in Electromagnetically Induced Transparency

We identify form-stable coupled excitations of light and matter (``dark-state polaritons'') associated with the propagation of quantum fields in Electromagnetically Induced Transparency. The properties of the dark-state polaritons such as the group velocity are determined by the mixing angle between light and matter components and can be controlled by an external coherent field as the pulse propagates. In particular, light pulses can be decelerated and ``trapped'' in which case their shape and quantum state are mapped onto metastable collective states of matter. Possible applications of this reversible coherent-control technique are discussed.Comment: 4 pages, 2 figure

Parametric Self-Oscillation via Resonantly Enhanced Multiwave Mixing

We demonstrate an efficient nonlinear process in which Stokes and anti-Stokes components are generated spontaneously in a Raman-like, near resonant media driven by low power counter-propagating fields. Oscillation of this kind does not require optical cavity and can be viewed as a spontaneous formation of atomic coherence grating

X-ray Emission from the 3C 273 Jet

We present results from four recent Chandra monitoring observations of the jet in 3C 273 using the ACIS detector, obtained between November 2003 and July 2004. We find that the X-ray emission comes in two components: unresolved knots that are smaller than the corresponding optically emitting knots and a broad channel that is about the same width as the optical interknot region. We compute the jet speed under the assumption that the X-ray emission is due to inverse Compton scattering of the cosmic microwave background, finding that the dimming of the jet X-ray emission to the jet termination relative to the radio emission may be due to bulk deceleration.Comment: 2 pages, 2 figures, to appear in the proceedings of "The X-ray Universe 2005", San Lorenzo de El Escorial (Spain), 26-30 September 200

Storage of light in atomic vapor

We report an experiment in which a light pulse is decelerated and trapped in a vapor of Rb atoms, stored for a controlled period of time, and then released on demand. We accomplish this storage of light by dynamically reducing the group velocity of the light pulse to zero, so that the coherent excitation of the light is reversibly mapped into a collective Zeeman (spin) coherence of the Rb vapor