Spectral- and frequency-encoded fluorescence imaging

A method for obtaining fluorescence images with a high number of resolvable points by using spectral and frequency encoding is presented. Broadband excitation light is encoded with a wavelength-dependent frequency modulation and dispersed onto the sample with a grating to simultaneously illuminate an entire image line. The Fourier transform of the frequency-encoded fluorescence emission provides one line of the image. Mechanical scanning along a direction orthogonal to the wavelength-encoded axis allows creation of the two-dimensional fluorescent image. This method is applicable for developing submillimeter diameter endoscopes. The principles of the technique are validated by imaging indocyanine green fluorescence in microfluidic channels.     

How Common Are True Aminopyridinato Complexes?

An overview over the binding situation in transition metal and lanthanide aminopyridinato complexes is given. True aminopyridinato complexes in which we observe a significant longer N‐amido than N‐pyridine bond length are rare and for instance observed for ruthenium. Additional examples of ruthenium aminopyridinato complexes were synthesized and characterized by X‐ray crystal structure analysis.     

Acceleration and slowing down of nonlinear wave packets in a weakly nonuniform plasma

The processes of acceleration of nonlinear waves in a weakly inhomogenous plasma and slowing down due to nonlinear Landau damping are compared. For initially standing waves the time needed for reaching equilibrium between these oppossing tendencies is estimated.     

Nonlinear Standing Langmuir Waves

The structure of stationary nonlinear standing Langmuir waves is examined in a self-consistent manner. A singularity for the stationary wave function is found which may cause the Langmuir waves to collapse, or expand indefinitely.     

Connection between light cone singularities and the asymptotic behaviour of the moments of the structure functions

On the basis of the Dyson-Jost-Lehmann representation a light-cone type expansion of the matrix elements of the current commutator can be justified. Suitable moments of the structure functions being defined, the connection between the asymptotic behaviour of the moments as Q² → ∞ and the behaviour of the expansion coefficients as x² → 0 is investigated. To solve this problem a restriction of the allowed class of generalized functions is needed. Then a one-to-one correspondence between both limits can be established.     

A microelectrochemical sensing system for the determination of Epstein–Barr virus antibodies

An electrochemical method for the detection of Epstein–Barr virus (EBV) infections is described. The method relies on an immunoassay with electrochemical read-outs based on recombinant antigens. The antigens are immobilised on an Au electrode surface and used to complementarily bind antibodies from serum samples found during different stages of infection with EBV. Thiol chemistry under formation of self-assembled monolayers functions as a means to immobilise the antigens at the Au electrodes. A reporter system consisting of a secondary antibody labelled with alkaline phosphatase is used for electrochemical detection. The feasibility of the assay design is demonstrated and the assay performance is tested against the current gold standard in EBV detection. Close correlation is obtained for the results found for the developed electrochemical immunoassay and a standard line assay. Moreover, the electrochemical immunoassay is combined with a nanoporous electrode system allowing signal amplification by means of redox recycling. An amplification factor of 24 could be achieved.