Generation of 35 kW peak power 80 fs pulses at 2.9 µm from a fully fusion-spliced fiber laser.

Tunable femtosecond light sources in the short wave and middle wave infrared regions are of utmost importance for various applications ranging from multiphoton microscopy, mid-infrared supercontinuum generation to high-harmonic generation. We report on an all-fusion-spliced fiber laser emitting 80 fs pulses up to 2.9 µm with 35 kW peak power. The laser is based on Raman self-frequency shift effect from 1560 nm up to 3000 nm in germanium-doped fibers fabricated by the widespread modified chemical vapor deposition process.

Two-photon microscopy with a frequency-doubled fully fusion-spliced fiber laser at 1840 nm.

We introduce a fiber-based laser system providing 130 fs pulses with 3.5 nJ energy at 920 nm at a 43 MHz repetition rate and illustrate the potential of the source for two-photon excited fluorescence microscopy of living mouse brain. The laser source is based on frequency-doubling high-energy solitons generated and frequency-shifted to 1840 nm in large mode area fibers. This simple laser system could unleash the potential of two-photon microscopy techniques in the biology laboratory where green fluorescent proteins with two-photon absorption spectrum peaking around 920 nm are routinely used.

First On-Sky Fringes with an Up-Conversion Interferometer Tested on a Telescope Array.

The Astronomical Light Optical Hybrid Analysis project investigates the combined use of a telescope array interferometer and nonlinear optics to propose a new generation of instruments dedicated to high-resolution imaging for infrared astronomy. The nonlinear process of optical frequency conversion transfers the astronomical light to a shorter wavelength domain. Here, we report on the first fringes obtained on the sky with the prototype operated at 1.55 µm in the astronomical H band and implemented on the Center for High Angular Resolution Astronomy telescope array. This seminal result allows us to foresee a future extension to the challenging midinfrared spectral domain.

Laboratory demonstration of spatial-coherence analysis of a blackbody through an up-conversion interferometer.

In the field of high resolution imaging in astronomy, we experimentally demonstrate the spatial-coherence analysis of a blackbody using an up-conversion interferometer in the photon counting regime. The infrared radiation of the blackbody is converted to a visible one in both arms of the interferometer thanks to the sum-frequency generation processes achieved in Ti-diffused periodically poled lithium niobate waveguides. The coherence analysis is performed through a dedicated imaging stage which mimics a classical telescope array analyzing an astrophysical source. The validity of these measurements is confirmed by the comparison with spatial-coherence analysis through a reference interferometer working at infrared wavelengths.

[Incidence of and mortality from malignant tumors inthe municipality of++Vila Nova de Gaia: 1981-1987]. / Incidência e mortalidade por tumores malignos no Concelho de Vila Nova de Gaia: 1981-1987.

Data from the population based Cancer Registry of Vila Nova de Gaia for the 1981-1987 period are presented. Cancer is becoming a disease increasingly frequent in Portugal, causing progressively higher mortality rates. Population and geographic characteristics of Vila Nova de Gaia country is presented. Information sources of this Registry are hospitals, pathology labs, Health Authority files and death certificates. Net (229.2, 216.6) and standardized for european population (369.9, 245.9) incidence rates are presented for respectively men and women. Comparisons with registries from other countries (e.s.) are made.