Publications by authors named "Daniel Kolbe"

Parental age impacts offspring quantity and quality. Most prior research focused on maternal age. Since in most organisms the mother produces the costly eggs plus provides all or most parental care, it is difficult to distinguish maternal effects mediated via the egg from later maternal care.

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Variation in apolipoprotein E (APOE) has been shown to have the strongest genetic effect on human longevity. The aim of this study was to unravel the evolutionary history of the three major APOE alleles in Europe by analysing ancient samples up to 12,000 years old. We detected significant allele frequency shifts between populations and over time.

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Longevity is a complex phenotype influenced by both environmental and genetic factors. The genetic contribution is estimated at about 25%. Despite extensive research efforts, only a few longevity genes have been validated across populations.

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We devise a laser-controlled adaptive optical element that operates intracavity under high-intensity radiation. This element substitutes a conventional mechanically deformable mirror and is free of critical heat-sensitive components and electronics. The deformation mechanism is based on the projection of a continuous-wave control laser onto a specially designed mirror.

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We present a double-pass scheme for high-efficiency, high-power, second-harmonic generation (SHG) in a single MgO-doped periodically poled stoichiometric lithium tantalate (MgO:PPSLT) crystal. The device is pumped by a single-frequency, continuous-wave fiber amplifier laser system at a wavelength of 1091 nm. For the double-pass scheme, a conversion efficiency of 60% and a harmonic power of 12.

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Efficient continuous-wave four-wave mixing by using three different fundamental wavelengths with individual detunings to resonances of the nonlinear medium is shown. Up to 6 μW of vacuum ultraviolet light at 121 nm can be generated, which corresponds to an increase of three orders of magnitude in efficiency. This opens the field of quantum information processing by Rydberg entanglement of trapped ions.

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We demonstrate the first cw two-photon absorption laser-induced stimulated emission. The 7(1)S(0)-6(1)P(1) transition in mercury at a 1014 nm wavelength is used, and selective lasing of different isotopes is observed.

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A coherent continuous-wave Lyman-alpha source based on four-wave sum-frequency mixing in mercury vapor has been realized with solid-state lasers. The third-order nonlinear susceptibility is enhanced by the 6(1)S - 7(1)S two-photon resonance and the near 6(1)S-6(3)P one-photon resonance. The phase matching curve for this four-wave mixing scheme is observed for the first time.

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