Steffen Rieger's research while affiliated with University of Münster and other places

... CatSper-deficient patients suffer from male infertility but are otherwise healthy except for the rare cases of deafness-infertility syndrome in which a genomic region encompassing contiguous CATSPER2 and STRC is deleted (49). Among the thirteen CATSPER genes that encode either CatSper α-subunits or ancillary subunits, only four genes have been reported to underlie asthenozoospermia in human infertility (48,49,68,69,78,(107)(108)(109), thereby illustrating the practical difficulties of identifying damaging mutations that cause infertility in humans. Considering the large number of genes required to form the CatSper channel complex and that knockout mice of eight Catsper genes all have similar infertility phenotypes without any gross abnormality, more mutations in other CATSPER genes are expected to be discovered from infertile males in the future. ...

... Next, we investigated the effects of curvature gradients on lipid sorting by measuring quantitative and spatially resolved information regarding the abundance of different lipid types within the bilayer. Because the C-H stretching region of the Raman spectrum contains contributions from all lipids, it is difficult to discriminate between different types of lipids, although more complex statistical methods have been shown to be able to overcome this for the fingerprint (43) and C-H region (44). Therefore, we used stable isotope labeling to isolate the Raman bands corresponding to the labeled molecular species. ...

... Initial theoretical and experimental studies involving super-resolution coherent Raman focused on using CARS. These include obtaining resolution enhancement through interferometry (87), pulse shaping (88)(89)(90)(91), signal saturation (92,93), and ground state depletion (94,95). While these methods offered improvements in resolution, many are limited to extremely high fluxes at the focal point. ...

... High-quality OFC with a large number of comb lines, high flatness of comb line power, and tunable frequency spacing is the current research focus. OFC can be generated based on mode-locked laser [6,7], nonlinear fiber [8], micro-ring resonator [9], photoelectric oscillator [10,11], and external modulator [12][13][14][15][16][17][18][19]. Among these methods, using external modulator has the advantages of stable output spectrum, adjustable frequency spacing between comb lines, simple structure, and flexible operation. ...

... Instead, a frequency actuator is often required to regulate the repetition frequency by stretching a section of the intracavity fiber. Although some research groups [47,48] have reported the repetition frequency stabilization method based on the refractive index regulation by adjusting the pump power of the oscillator. This all-optical scheme shows a large bandwidth but also has an evident drawback of small tuning range and an additional pump laser diode is often required. ...