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OBJECTIVE The study was conducted to assess the efficacy and rate of complications of endovenous laser treatment (EVLT) of the short saphenous vein (SSV). METHODS During a 17-month period, 210 (187 patients) with SSV incompetence documented by duplex ultrasound studies were treated with EVLT using a 980-nm diode laser. Duplex ultrasound examinations were(More)
It is proposed that the process of nonlinear optical phase conjugation can be utilized to compensate for channel dispersion and hence to correct for temporal pulse broadening. Specifically, a four-wave nonlinear interaction is shown to achieve pulse renarrowing. Spectral bandwidth phase-conjugate interaction parameters. Recent theoretically and(More)
A nonlinear optical technique is described that performs, essentially instantaneously, the functions of spatial correlation and convolution of spatially encoded waves. These real-time operations are accomplished by mixing spatially dependent optical fields in the Fourier-transform plane of a lens system. The use of a degenerate four-wave mixing scheme(More)
We demonstrate theoretically that the distortion-correction property of phase-conjugate beams propagating in reverse through aberrating media is also operative when the indices of refraction of the media depend on the intensity. A necessary condition is that the phase-conjugate mirror that generates the reflected beam possess a unity (magnitude)(More)
Schema mappings are logical assertions that specify the relationships between a source and a target schema in a declarative way. The specification of such mappings is a fundamental problem in information integration. Mappings can be generated by existing mapping systems (semi-)automatically from a visual specification between two schemas. In general, the(More)
A number of new optical effects that result from degenerate four-wave mixing in transparent optical media are proposed and analyzed. The applications are relevant to time-reversed (phase-conjugated) propagation as well as to a new mode of parametric oscillation. The purpose of this Letter is to examine briefly the consequences of a certain class of(More)
It is shown that a nearly degenerate four-wave mixing process is capable of yielding a real-time optical bandpass filter. The filter has a large field of view and is capable of providing an amplified bandpass. Moreover, the conjugate nature of the output field can be utilized to increase the signal-to-noise ratio of the device. For a 1-cm interaction length(More)
We have demonstrated an all-optical diagnostic system that enhances the observation of defects in periodic structures. This real-time technique employs a spatial light modulator as a smart-pixel array for information processing in the Fourier transform plane of a lens. The system also includes a phase-conjugate mirror for autoalignment and for correction of(More)
BACKGROUND Unmanned Aerial Systems (UAS or drones) could potentially be used for the routine transport of small goods such as diagnostic clinical laboratory specimens. To the best of our knowledge, there is no published study of the impact of UAS transportation on laboratory tests. METHODS Three paired samples were obtained from each one of 56 adult(More)
We report on the observation of cw backward-wave generation using degenerate four-wave mixing in a nonresonant medium. The interaction took place inside a 3-m-long CS 2-filled 4-jAm i.d. optical fiber. With a pump power of only 6 mW inside the fiber, a backward-wave conversion efficiency of 0.45% has been observed, which is in reasonable agreement with(More)