Publications by authors named "F Medard"

We demonstrate edge-emitting exciton-polariton (polariton) laser operation from 5 to 300 K and polariton amplifiers based on polariton modes within ZnO waveguides. The guided mode dispersion below and above the lasing threshold is directly measured using gratings placed on top of the sample, fully demonstrating the polaritonic nature of the lasing modes. The threshold is found to be smaller than that expected for radiative polaritons in planar ZnO microcavities below 150 K and comparable above.

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Widegap III-nitride alloys have enabled new classes of optoelectronic devices including light emitting diodes, lasers and solar cells, but it is admittedly challenging to extend their operating wavelength to the yellow-red band. This requires an increased In content x in In Ga N, prevented by the indium segregation within the miscibility gap. Beyond the known advantage of dislocation-free growth on dissimilar substrates, nanowires may help to extend the compositional range of InGaN.

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This study examined whether adding levofloxacin to a standard four-drug regimen improved the 8-week culture response and compared effectiveness of 9 versus 6 months of intermittent therapy for human immunodeficiency virus-related pansusceptible pulmonary tuberculosis. Patients were randomized to receive either four or five drugs, the fifth being levofloxacin. Patients who completed induction therapy were randomized to complete 9 versus 6 months of intermittent therapy with isoniazid and rifampin.

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Objectives: A directly observed therapy program was established at Harlem Hospital, New York, NY, in 1993 to promote high tuberculosis treatment completion rates.

Methods: The Harlem program used an on-site surrogate family model. Treatment completion rate, visit adherence rate, human immuno-deficiency virus seroprevalence, and time to sputum culture conversion were assessed.

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With the increased incidence of tuberculosis and especially of resistant cases in the United States, directly observed therapy as a mechanism for ensuring completion of therapy has been advocated. This mechanism has been primarily pioneered and utilized in developing countries. Few models have been tailored to specific patient populations in this country.

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