Astronomical optical frequency comb generation and test in a fiber-fed MUSE spectrograph

We here report on recent progress on astronomical optical frequency comb generation at innoFSPEC-Potsdam and present preliminary test results using the fiber-fed Multi Unit Spectroscopic Explorer (MUSE) spectrograph. The frequency comb is generated by propagating two free-running lasers at 1554.3 and 1558.9 nm through two dispersionoptimized nonlinear fibers. The generated comb is centered at 1590 nm and comprises more than one hundred lines with an optical-signal-to-noise ratio larger than 30 dB. A nonlinear crystal is used to frequency double the whole comb spectrum, which is efficiently converted into the 800 nm spectral band. We evaluate first the wavelength stability using an optical spectrum analyzer with 0.02 nm resolution and wavelength grid of 0.01 nm. After confirming the stability within 0.01 nm, we compare the spectra of the astro-comb and the Ne and Hg calibration lamps: the astro-comb exhibits a much larger number of lines than lamp calibration sources. A series of preliminary tests using a fiber-fed MUSE spectrograph are subsequently carried out with the main goal of assessing the equidistancy of the comb lines. Using a P3d data reduction software we determine the centroid and the width of each comb line (for each of the 400 fibers feeding the spectrograph): equidistancy is confirmed with an absolute accuracy of 0.4 pm

CYFRA 21-1 is a prognostic determinant in non-small-cell lung cancer: results of a meta-analysis in 2063 patients

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Amaninamide, a new toxin ofAmanita virosa mushrooms

Amaninamide, a toxin closely related to the family of amatoxins, was found exclusively in Amanita virosa mushrooms. It differs from the well known toxin alpha-amanitin in that it lacks the 6'-hydroxyl group of the tryptophan unit, and from the toxin amanin found in Amanita phalloides by the presence of a carboxamide group instead of a carboxylic acid groups

Virotoxins: actin-binding cyclic peptides of Amanita virosa mushrooms

Virotoxins are toxic peptides singularly found in Amanita virosa mushrooms. After purification and resolution by high-pressure liquid chromatography, the main component, viroisin, was selectively cleaved and submitted to Edman degradation. The structure could be completely elucidated and was in part found to be the same as in phallotoxins. Differing from the phallotoxins, however, virotoxins are monocyclic peptides and contain D-serine instead of L-cysteine. In addition, two amino acids were detected in virotoxins which thus far have not been found in nature: 2,3-trans-3,4-dihydroxy-L-proline and 2'-(methylsulfonyl)-L-tryptophan. The biological activity of viroisin is comparable to that of the phallotoxins: e.g., with 2.5 mg of viroisin per kg (white mouse), 50% of the animals die within 2-5 h by hemorrhagia of the liver. Also, on the molecular level, the virotoxins behave similar to the phallotoxins. Thus, viroisin binds to rabbit muscle actin as proved by difference UV spectroscopy. With an apparent equilibrium dissociation constant KD approximately 2 x 10(-8) M, the affinity of viroisin is very similar to that of phalloidin. However, the flexibility of the monocyclic structure and the presence of two additional hydroxy groups in the virotoxins suggest a different mode of interaction with actin. While there is proof that the bicyclic phallotoxins possess a rigid binding site, the virotoxins may adopt the biologically active conformation by an induced-fit mechanism upon contact with actin

Potential, Limitations and Challenges of Markerless Registration with the DLR 3D-Modeller in Medical Applications.

Registration is necessary whenever planning data (e.g. biopsy needle trajectories based on preoperative images) have to be transferred into the operation room (OR). In numerous medical interventions a successful registration is crucial for the quality of the medical procedure, including radio surgery and navigated surgery. Often standard approaches in clinical use are based either on artificial landmarks or anatomical landmarks, e.g. the manubrium. Markerless methods using e.g. the patient skin or bone surface are in clinical use, too (e.g. z-touch from BrainLAB). However, contact free systems still lack of dexterity and accuracy and are a current research topic. This work analyses a markerless and contact free registration using the advanced DLR 3D-Modeller (3DMo). The 3D-Modeller allows for acquiring the patient surface intraoperatively using three different methods: a stereo camera sensor (SCS), a laser-range scan (LRS), and a light-stripe profiler (LSP)