Practical technique for improving all-fiber coherent combination of multistage high-power ytterbium fiber amplifiers.

We demonstrate coherent combination of two high-gain and high-power single-mode 1 μm fiber amplifiers via direct pump current modulation. Each all-fiber amplifier channel, which is built as a master oscillator-multiple amplifier architecture, can operate either continuous waves or 4 ns, 1 MHz pulses with average power of 50 W and more than 55 dB gain. These two amplifiers are coherently combined by modulating the pump currents of the preamplifiers in a multidither arrangement.

Self-organized coherence in fiber laser arrays.

We report the production of stable, coherent, and same-phase states in arrays of fiber lasers. Provided that proper interactions between the lasers are present, arrays will spontaneously self-organize into stable coherent same-phase states. There is no need for active control.

[Studies of the in vitro toxicity of D-penicillamine in the Chinese hamster ovary system].

The amino-thiol-containing compound D-penicillamine is used as a disease-modifying drug in the treatment of rheumatoid arthritis. In the present study the effects of D-penicillamine on Chinese hamster ovary cells (CHO) were evaluated. It could be shown that only high doses, i.

Thiopyronine-sensitized photodynamic effect on cell growth, RNA and DNA synthesis of Chinese hamster ovary cells.

After treatment of Chinese hamster ovary (CHO) cells with very low concentrations of thiopyronine (TP; 1 microgram/ml) and visible light, a delay in growth of cell cultures (prolongation of the lag phase] was observed. The lengthened lag phase, however, was followed by normal growth of the cells. The length of the lag period is dependent on the irradiation dose applied.

The effect of pentachlorophenol and its metabolite tetrachlorohydroquinone on RNA, protein, and ribosome synthesis in Saccharomyces cells.

The effect of pentachlorophenol (PCP) and its metabolite tetrachlorohydroquinone (TCH) were tested on growth, RNA, protein and ribosome syntheses, and ribosome content in yeast cells. Cells exposed to increasing concentrations of PCP show increasing inhibition to RNA and ribosome synthesis, and to cell growth. TCH causes a delay of the growth of the cell culture (prolongation of the lag phase) but does not cause inhibition.

Investigation of a test system for the rapid differentiation of nuclear and cytoplasmic damage in eucaryotes.

The effect of various agents which cause cell inactivation on the growth curves and RNA synthesis rates of yeast cells has been studied. On the basis of these investigations it was concluded that such studies can be used as a rapid test system for drawing preliminary conclusions as to whether a particular agent primarily damages the DNA of the cell nucleus or cytoplasmic structures.

The effect of trichloroethylene and acrylonitrile on RNA and ribosome synthesis and ribosome content in Saccharomyces cells.

The effects of trichloroethylene (TCE) and acrylonitrile (ACN) on growth, RNA synthesis, ribosome synthesis, and ribosome content were tested in yeast cells. TCE causes a delay of the growth of a cell culture (prolongation of the lag phase), but does not cause inhibition. Cells exposed to increasing concentrations of ACN show increasing damage, so that, at a certain point of the growth curve, cell division stops altogether.