The Mercator Advanced Imager for Asteroseismology (MAIA) is being designed particularly for asteroseismology of hot subdwarf stars on the 1.2m Mercator Telescope. In order to achieve the required precision on the pulsation amplitude ratios, the photometric variations must be measured simultaneously in several bands with respect to constant reference stars in the field. MAIA is an optical imager to observe simultaneously in three color bands, corresponding approximately with an SDSS u, g, r+i+z photometric system. The fully dioptric design uses a common collimator, two dichroic beam splitters (cut-offs at 390nm and 550nm) and three cameras. Each camera holds a fast frame-transfer CCD cooled down to -90°C with a compact Stirling cryocooler. All lenses are axially and radially constrained by a calibrated spring load, with radial adjustment mechanisms to calibrate the centering of each lens. The differential thermal expansion of the optical system is compensated by the thermal expansion of the different materials in the mechanical mountings, resulting in a design that is insensitive to thermal variations. Specific care has been taken to reduce the effect of manufacturing tolerances on the performance of the instrument. The tilt angle of two of the beam splitters is adjustable in two dimensions to compensate for remaining misalignment in the optical system. Finite element models have been constructed to verify that the structural flexure and structural dynamics are within the requirements. A tool has been developed to estimate the performance of the instrument based on the design parameters. Various commercial software tools have been used to optimize the workflow in this complex system design.

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The Mercator Advanced Imager for Asteroseismology (MAIA) is being designed particularly for asteroseismology of hot subdwarf stars. In order to achieve the required precision on the pulsation amplitude ratios, the photometric variations must be measured simultaneously in several bands with respect to constant reference stars in the field. MAIA is an optical imager to observe simultaneously in three color bands, corresponding approximately with an SDSS u, g, r+i+z photometric system. The fully dioptric design uses a common collimator, two dichroic beam splitters (cut-offs at 390nm and 550nm) and three cameras. MAIA covers a wide field of view (FoV) of 9.4' x 14.1' with a sampling of 0.27"/pix on the 1.2m Mercator Telescope. When replacing the collimator and with a modest reduction of the FoV, its host can also be used on larger telescopes. Each camera holds a fast-frame-transfer charge coupled device (CCD), cooled by three four-stage Peltier elements to -70 degrees C. The mechanical design minimizes structural flexure. Selected optical elements are mounted in quasi-isostatic lens mounts to minimize the effects of temperature variations.

This paper discusses the minimization of the fuel consumption of a gasoline engine through dynamic optimization. The minimization uses a mean value model of the powertrain and vehicle. This model has two state variables: the pressure in the engine intake manifold and the engine speed. The control input is the throttle valve angle. The model is identified on a universal engine dynamometer. Optimal state and control trajectories are calculated using Bock's direct multiple shooting method, implemented in the software MUSCOD-II. The developed approach is illustrated both in simulation and experimentally for a generic test case where a vehicle accelerates from 1100rpm to 3700rpm in 30s. The optimized trajectories yield minimal fuel consumption. The experiments show that a linear engine speed trajectory yields an extra fuel consumption of 13% when compared to the optimal trajectory. It is shown that, with a simple model, a significant amount of fuel can be saved without loss of the fun-to-drive.

High-resolution melting curve analysis is a closed-tube fluorescent technique that can be used for genotyping and heteroduplex detection after polymerase chain reaction. We applied this technique at the HLA-A locus and suggest that this method can be used as a rapid, inexpensive screen between siblings prior to living-related transplantation. At any locus, there are seven general cases of shared alleles among two individuals, ranging from identical homozygous genotypes (all alleles shared) to two heterozygous genotypes that share no alleles. We studied each case using previously typed cell lines to show that identity or non-identity can be determined in all cases by high-resolution melting curve analysis. HLA genotype identity is suggested when two individuals have the same melting curves. Identity is confirmed by comparing the melting curve of a 1:1 mixture with the individual melting curves. Non-identity at the amplified locus changes the heteroduplexes formed in the mixture compared with the original samples and alters the shape of the melting curve. The technique was tested on DNA from a 17-member CEPH family. High-resolution melting curve analysis revealed six different genotypes in the family. The genotype clustering was confirmed by sequence-based typing. Although this technique does not sequence or determine specific HLA alleles, it does rapidly establish identity at highly polymorphic HLA loci. The technique may also prove useful for confirmation of HLA genotypic identity between unrelated individuals prior to allogeneic hematopoietic stem-cell transplantation.

Hydrophobicity and bioaccumulation potential of linear and cyclic polydimethylsiloxane (PDMS) oligomers were estimated by reversed‐phase liquid chromatography and feeding experiments with guppies (Poecilia reticulata). PDMS concentrations in fish were determined by capillary column gas chromatography and gas chromatography‐mass spectrometry. In contrast to polychlorinated biphenyls (PCBs), only very small amounts of PDMS were retained by the fish after six weeks feeding.