RESUMO
An interferometric quantum cryptographic system at 1550nm wavelength using gated InGaAs Avalanche Photo Diodes as single-photon receivers is demonstrated for a transmission distance up to 40 km.
RESUMO
The persistent extinction of fluorescence emission of Eu(3+) in glasses activated with europium and cerium is reported for the first time to the authors' knowledge. The glass samples containing Eu(3+) and Ce(3+) were initially colorless and transparent and exhibited intense emission peaks at 592 and 612 nm assigned to the (5)D(0)-(7)F(1, 2) transitions of Eu(3+). The complete extinction of the Eu(3+)-ion emission was obtained as an effect of multipulse excimer-UV-laser (lambda = 248 nm, tau(FWHM) >/= 20 ns) irradiation of the glass samples. Fluorescence microscopy, Mössbauer spectrometry, and electron spin resonance were applied for investigation of the modifications induced by the laser treatment. As a decisive proof of the extinction of fluorescence we succeeded in recording three-dimensional fluorescent photographic patterns within the activated samples.
RESUMO
Patients who are on neuroleptics with acute akathisia improve more with opioid therapy than patients who are off neuroleptics with tardive akathisia. Since tardive akathisia usually occurs after long term neuroleptic exposure, we propose that this difference in therapeutic response is due to permanent changes in receptor sensitivity that arise from such prolonged exposure. We have previously described a patient with severe acute akathisia whose motor restlessness was totally suppressed by opioid therapy. This improvement was rapidly reversed by the opiate receptor blocker naloxone. This suggests that the endogenous opiate system is involved in the pathogenesis of neuroleptic-induced akathisia.