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S Radic

Publications and source records attributed to S Radic.

3 recordsLinked to original sources

Pump-noise transfer in dual-pump fiber-optic parametric amplifiers: walk-off effects.

Transfer of intensity noise from pumps to signal in dual-pump fiber-optic parametric amplifiers is simulated numerically for a realistic configuration in which both pumps are amplified and filtered before they enter the fiber. The walk-off effects induced by different group velocities of pumps, signal, and idler are fully taken into account. It is found that the optical signal-to-noise ratio can be as low as 15 dB when the amplifier length is close to 0.5 km, but it can be improved by 3 dB or so by use of longer fibers.

Journal Article↗

Reduction of soliton phase jitter by in-line phase conjugation.

The main impairment of differential-phase-shift-keyed communication systems is phase jitter. Noise-induced phase jitter, which is mediated by self-phase modulation, can be reduced significantly by a small number of in-line phase conjugators.

Journal Article↗

Nucleolar volume in breast carcinomas.

The prognostic value of histopathological typing of breast carcinomas is relatively good. The determination of cell size has been a common and useful parameter in the diagnosis of various malignancies. With modern stereologic methods it is possible to obtain unbiased estimates of nucleolar volume. The aim of this study was to present our data regarding the nucleolar size in breast carcinoma. Patients treated for breast carcinoma (n = 39) were retrieved and randomly selected from the files of the University Institute of Pathology, Nis. Histological sections (4 microns) were cut from each of the routinely processed, paraffin-embedded tissue blocks and stained with hematoxylin and eosin. A Carl Zeiss NU-1 microscope equipped with a x 100 oil-immersion lens (N.A. = 1.25) and eyepiece graticule was used for stereological measurements. A total magnification of x 1600 was used. A simple grid was used for point sampling of nucleolar intercepts, which were measured in one arbitrary direction. By multiplying the averaged, cubed intercept length by pi/3, an unbiased estimate of volume-weighted nucleolar volume was obtained. The nucleolar volume was significantly larger in invasive ductal carcinoma (12.34 +/- 3.48 microns3) than invasive lobular carcinoma (5.6 +/- 2.73 microns 3) and mucinous (colloid) adenocarcinoma (0.88 +/- 0.42 micron 3). Various histological types of breast cancer exhibit differences with regard to nucleolar volume.

Adult↗