Optimizing pulse compressibility in completely all-fibered Ytterbium chirped pulse amplifiers for in vivo two photon laser scanning microscopy.

A simple and completely all-fiber Yb chirped pulse amplifier that uses a dispersion matched fiber stretcher and a spliced-on hollow core photonic bandgap fiber compressor is applied in nonlinear optical microscopy. This stretching-compression approach improves compressibility and helps to maximize the fluorescence signal in two-photon laser scanning microscopy as compared with approaches that use standard single mode fibers as stretcher. We also show that in femtosecond all-fiber systems, compensation of higher order dispersion terms is relevant even for pulses with relatively narrow bandwidths for applications relying on nonlinear optical effects. The completely all-fiber system was applied to image green fluorescent beads, a stained lily-of-the-valley root and rat-tail tendon. We also demonstrated in vivo imaging in zebrafish larvae, where we simultaneously measure second harmonic and fluorescence from two-photon excited red-fluorescent protein. Since the pulses are compressed in a fiber, this source is especially suited for upgrading existing laser scanning (confocal) microscopes with multiphoton imaging capabilities in space restricted settings or for incorporation in endoscope-based microscopy.

Health care technology in the Federal Republic of Germany.

The basic goal of the German health care system is equal access to all medical services for all citizens. The federal government sets the legal framework for the system, but most health policy decisions are made through bargaining between large organizations within a legal framework. The federal government took little active role in health care until the early 1990s, when it became increasingly apparent that budgeting and other cost containment measures seemed to be insufficient to successfully reduce the growth of mandatory sickness funds expenditures. A 1993 law has attempted to address some of the most obvious deficiencies in the system, while encouraging a market-oriented approach to health care. Health care technology assessment has almost no role in the German health care system. Attempts by professionals and politicians to introduce technology assessment into the health care arena have been largely unsuccessful.