[Aim and functioning of the attending staff of geriatric hospitals]. / Buts et fonctionnement de l'équipe soignante en gériatrie.

After having described the situation of the elderly in general and more specifically at the Geriatric Hospital which is a part of the Geriatric institutions of Geneva, the authors remind of the concept regarding the integrated medicine of Prof. J. -P. Junod, their head physician: "The contribution of psychiatry to the entire field of geriatry assumes an essential and irreplaceable character. This major contribution aims to convert it into a really integrated branch of medicine. "Integrated medicine consists in a therapeutic treatment applied by a multidisciplinary staff and aimed at the patient in general. Geriatry requires a global approach of the case taking in consideration the great many medical, psychological, family or social factors which enable to establish a prognosis as well as a therapeutic programme. This integrated medicine is also applied in cooperation with and for the benefit of the attending staff, who finds personal and professional reward within the combination of following three factors: education, therapy and research, which in turn institution, the geriatry as well as for the gerontology in general.

Continuous-wave 1.55 microm diode-pumped surface emitting semiconductor laser for broadband multiplex spectroscopy.

A room-temperature-operating vertical external cavity surface emitting laser is applied around 1550 nm to intracavity laser absorption spectroscopy analyzed by time-resolved Fourier-transform interferometry. At an equivalent path length of 15 km, the high-resolution spectrum of the semiconductor disk laser emission covers 17 nm simultaneously. A noise-equivalent absorption coefficient at 1 s averaging equal to 1.5 x 10(-10) cm(-1)Hz(-1/2) per spectral element is reported for 65 km, the longest path length employed.

Efficient diode-pumped Yb3+:Y2SiO5 and Yb3+:Lu2SiO5 high-power femtosecond laser operation.

We report the mode-locked operation of two new Yb-doped oxyorthosilicates, Y2SiO5 (YSO) and Lu2SiO5 (LSO), that are longitudinally diode pumped. Yb:YSO supplied pulses as short as 122 fs with 410 mW of output power at 1041 nm. More than 2.6 W of average output power, for pulse durations of 198 fs at 1044 nm and 260 fs at 1059 nm for Yb:YSO and Yb:LSO, respectively, were provided. These are, to our best knowledge, the highest values ever obtained and the most efficient mode-locked laser in such a classic fiber-coupled diode-pumping configuration.

High-power tunable diode-pumped Yb3+:CaF2 laser.

Results of diode-pumped cw laser operation of an Yb3+:CaF2 single crystal are reported for what is to our knowledge the first time. With a 5-at.% Yb3+ -doped sample we obtained 5.8-W output power at 1053 nm for 15 W of incident power at 980 nm. The laser wavelength could be tuned from 1018 to 1072 nm, and a small-signal gain as high as 1.8 was achieved, showing the great potential of Yb3+:CaF2 as an amplifier medium for femtosecond pulses.

High-power diode-pumped Yb3+:CaF2 femtosecond laser.

We report what is believed to be the first demonstration of a high-power passively mode-locked diode-pumped femtosecond laser based on an Yb3+:CaF2 single crystal, directly pumped by a 15-W fiber-coupled laser diode. With a 5-at. % Yb3+ -doped sample and prisms for dispersion compensation we obtained pulses as short as 150 fs, with 880 mW of average power and up to 1.4-W average output power, with a pulse duration of 220 fs, centered at 1049 nm. The laser wavelength could be tuned from 1040 to 1053 nm in the femtosecond regime. Using chirped mirrors for dispersion compensation, the oscillator provided up to 1.74 W of average power, with a pulse duration of 230 fs, corresponding to a pulse energy of 20 nJ and a peak power of 85 kW.