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The 2 S 1 / 2 - 2 P 1 / 2 and 2 S 1 / 2 - 2 P 3 / 2 transitions in Li-like carbon ions stored and cooled at a velocity of β ≈ 0.47 in the experimental storage ring (ESR) at the GSI Helmholtz Centre in Darmstadt have been investigated in a laser spectroscopy experiment. Resonance wavelengths were obtained using a new continuous-wave UV laser system and a novel extreme UV (XUV) detection system to detect forward emitted fluorescence photons. The results obtained for the two transitions are compared to existing experimental and theoretical data. A discrepancy found in an earlier laser spectroscopy measurement at the ESR with results from plasma spectroscopy and interferometry has been resolved and agreement between experiment and theory is confirmed. [ABSTRACT FROM AUTHOR]

T. N. NGUYEN [1] K. GEIGER [1] TH. WALTHER [2] The flow behavior of two commercial liquid crystalline polymers (LCP), Vectra B 950 and Vectra L 950 (Ticona GmbH), was [...]

We report on the cooling of neutral mercury in a magneto-optical trap utilizing the spin forbidden S → P transition at 253.7 nm. We trapped two Hg isotopes, i.e. the bosonic Hg and the fermionic Hg isotope, respectively. The temperature of the cold atom cloud was determined to be approximately 300 μK using a modified TOF-method. It is currently limited by the quality of the laser lock. Trapped neutral Hg has many interesting avenues such as a time standard and high precision measurements. Here, we discuss the possibilities of photo-association spectroscopy and the generation of ultra-cold Hg dimers. [ABSTRACT FROM AUTHOR]

In the present study, yeast colony development serves as a model system to study growth of fungal populations with negligible nutrient and signal transport within the mycelium. Mathematical simulations address the question whether colony development is governed by diffusional limitation of nutrients. A hybrid one-dimensional cellular automaton model was developed that describes growth of discrete cells based upon microscopic interaction rules in a continuous field of nutrient and messenger. The model is scaled for the geometry of the experimental setup, cell size, growth- and substrate uptake rates. Therefore, calculated cell density profiles and nutrient distributions can be compared to experimental results and the model assumptions can be verified. In the physiologically relevant parameter range, simulations show an exponentially declining cell density along the median axis of the colonies in case of a diffusion limited growth scenario. These results are in good agreement with cell density profiles obtained in cultivations of the yeast Candida boidinii with glucose as the limiting carbon source but stand in contrast to the constant cell density profile estimated for Yarrowia lipolytica grown under the same conditions. While from the comparison of experimental results and simulations a diffusion limited growth mechanism is proposed for glucose limited C. boidinii colonies, this hypothesis is rejected for the growth of Y. lipolytica. As an alternative, a quorum sensing model was developed that can explain the evolution of constant cell density profiles based on the effect of a not further characterized unstable or volatile messenger. [Copyright &y& Elsevier]

Abstract: It is urgently aimed in prenatal medicine to identify pregnancies, which develop life-threatening preeclampsia prior to the manifestation of the disease. Here, we use recurrence-based methods to distinguish such pregnancies already in the second trimester, using the following cardiovascular time series: the variability of heart rate and systolic and diastolic blood pressures. We perform recurrence quantification analysis (RQA), in addition to a novel approach, ε-recurrence networks, applied to a phase space constructed by means of these time series. We examine all possible coupling structures in a phase space constructed with the above-mentioned biosignals. Several measures including recurrence rate, determinism, laminarity, trapping time, and longest diagonal and vertical lines for the recurrence quantification analysis and average path length, mean coreness, global clustering coefficient, assortativity, and scale local transitivity dimension for the network measures are considered as parameters for our analysis. With these quantities, we perform a quadratic discriminant analysis that allows us to classify healthy pregnancies and upcoming preeclamptic patients with a sensitivity of 91.7% and a specificity of 45.8% in the case of RQA and 91.7% and 68% when using ε-recurrence networks, respectively. [Copyright &y& Elsevier]

Abstract: We report on our measurements of the Landé g-factors for rovibrational states in the 10V-band of carbon disulfide. Our improved accuracy enabled us to increase the measurements precision of previous studies and additionally determine the Landé g-factors for nearly all previously assigned transitions. [Copyright &y& Elsevier]