Abstract
A chirped fibre Bragg grating was written in an Erbium doped fibre. It was found that the slope of the reflected spectral power could be tuned by changing the pump power. The gratings fabricated were demonstrated to be useful in the development of a technique for optical interrogation of FBGs sensing heads with tunable sensitivity. © 2003 OSA/BGPP.

Abstract
A fibre Bragg grating interrogation technique with tunable sensitivity is reported. It relies on the utilization of the edge filtering concept applied to a chirped fibre Bragg grating (CFBG) written in an erbium-doped fibre as the processing element. Through the combination of the optical gain properties of the erbium-doped fibre and of the distributed wavelength reflection characteristics of the CFBG, it is possible to achieve different reading sensitivities and amplification of the remote sensing signal.

Abstract
A full characterization of reversible long-period fibre gratings produced through the wind of a string around a fibre/grooved tube set is presented. This technique enables a good control over the gratings isolation loss-peaks and has high repeatability. The tunability of the resonant wavelengths through the etching of the fibres cladding, prior to perform the gratings, have been investigated. These mechanically induced long-period fibre gratings have shown high sensitivity to loads.

Abstract
In this paper we present and evaluate the spectral response of uniform gratings written in different tapered core sections of single mode fibre. This combination of uniform gratings and tapers leads to three, types of Chirped Fibre Bragg Gratings with different reflection spectra and different mechanical properties. These devices are characterized in function of the applied strain, showing interesting chirp tunability.

Abstract
The development of modern molecular genetic techniques has allowed breast cancer researchers to clarify the multistep model of breast carcinogenesis. Laser capture microdissection coupled with comparative genomic hybridisation and/or loss-of-heterozygosity methods have confirmed that many pre-invasive lesions of the breast harbour chromosomal abnormalities at loci known to be altered in invasive breast carcinomas. Current data do not provide strong evidence for ductal hyperplasia of usual type as a precursor lesion, although some are monoclonal proliferations; however, atypical hyperplasia and in situ carcinoma appear to be nonobligate precursors. We review current knowledge and the contribution of molecular genetics in the understanding of breast cancer precursors and pre-invasive lesions.

Abstract
In this contribution we propose an alternative approach to the traditionally used apodized chirped fiber Bragg gratings for dispersion compensation applications. The unchirped grating proposed has a refractive index perturbation with varying negative mean, acting simultaneously as optical filter demultiplexer and efficient group velocity dispersion compensator in wavelength division multiplexing systems.