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The MASCOT Camera (MasCam) is part of the Mobile Asteroid Surface Scout (MASCOT) lander's science payload. MASCOT has been launched to asteroid (162173) Ryugu onboard JAXA's Hayabusa 2 asteroid sample return mission on Dec 3rd, 2014. It is scheduled to arrive at Ryugu in 2018, and return samples to Earth by 2020. MasCam was designed and built by DLR's Institute of Planetary Research, together with Airbus-DS Germany. The scientific goals of the MasCam investigation are to provide ground truth for the orbiter's remote sensing observations, provide context for measurements by the other lander instruments (radiometer, spectrometer and magnetometer), the orbiter sampling experiment, and characterize the geological context, compositional variations and physical properties of the surface (e.g. rock and regolith particle size distributions). During daytime, clear filter images will be acquired. During night, illumination of the dark surface is performed by an LED array, equipped with $4\times36$ monochromatic light-emitting diodes (LEDs) working in four spectral bands. Color imaging will allow the identification of spectrally distinct surface units. Continued imaging during the surface mission phase and the acquisition of image series at different sun angles over the course of an asteroid day will contribute to the physical characterization of the surface and also allow the investigation of time-dependent processes and to determine the photometric properties of the regolith. The MasCam observations, combined with the MASCOT hyperspectral microscope (MMEGA) and radiometer (MARA) thermal observations, will cover a wide range of observational scales and serve as a strong tie point between Hayabusa 2's remote-sensing scales ( $10^{3}$ - $10^{-3}\mbox{ m}$ ) and sample scales ( $10^{-3}$ - $10^{-6}\mbox{ m}$ ). The descent sequence and the close-up images will reveal the surface features over a broad range of scales, allowing an assessment of the surface's diversity and close the gap between the orbital observations and those made by the in-situ measurements. The MasCam is mounted inside the lander slightly tilted, such that the center of its 54.8° square field-of-view is directed towards the surface at an angle of 22° with respect to the surface plane. This is to ensure that both the surface close to the lander and the horizon are observable. The camera optics is designed according to the Scheimpflug principle, thus that the entire scene along the camera's depth of field (150 mm to infinity) is in focus. The camera utilizes a $1024\times1024$ pixel CMOS sensor sensitive in the 400-1000 nm wavelength range, peaking at 600-700 nm. Together with the f-16 optics, this yields a nominal ground resolution of 150 micron/px at 150 mm distance (diffraction limited). The camera flight model has undergone standard radiometric and geometric calibration both at the component and system (lander) level. MasCam relies on the use of wavelet compression to maximize data return within stringent mission downlink limits. All calibration and flight data products will be generated and archived in the Planetary Data System in PDS image format. [ABSTRACT FROM AUTHOR]

The kinetics of melphalan leakage into the peripheral blood were studied in 21 patients undergoing hyperthermic isolation perfusion of the upper or lower limb as an adjuvant treatment in high-risk melanoma; in 5 patients cisplatin was added. The melphalan concentrations in the peripheral blood rose predominantly during the first 20 min of perfusion and levelled out to an apparent steady state of about 0.28 micrograms/ml in upper extremity perfusions, and 0.34 (without cisplatin) and 0.37 micrograms/ml (with cisplatin) in lower extremity perfusion. Erythrocytes labelled with technetium Tc 99m, which were added concomitantly with melphalan to the perfusion medium, appeared in the systemic circulation of the patients at an almost constant rate of 0.32% (lower and upper limb perfusions without cisplatin and 0.37% (with cisplatin) of total tracer/min. This perfusate flow rate indicated by labelled erythrocytes completely explained the leakage of melphalan from the perfusion circuit into the peripheral blood. Peak concentrations of melphalan in the peripheral blood were observed immediately after reconstitution of normal hemodynamic conditions once isolation perfusion had been terminated. This fraction of melphalan might originate from tissue-binding sites, but also from vascular compartments; therefore, a thorough washing-out procedure might minimize this effect. [ABSTRACT FROM AUTHOR]

On many sea shores of the Niedersachsen coast, the polychaete Scolelepis squamata is the dominant animal species living in the sediment of exposed beaches.The population of the predatory species Eteone longa, with a main distribution in more sheltered intertidal and subtidal habitats, has a certain overlap with S. squamata. In these restricted areas, S. squamata suffers from a permanent pursuit by E. longa during low tide. Field and laboratory studies have revealed that this predator-prey relationship follows a distinct behavioural pattern and is an exploitation of surviving animals: the predator does not ingest the whole prey individual but only feeds on regenerable parts of the body. Both species draw characteristic tracks on the sediment surface that illustrate the phases of the chase, the attempts at defence and the mutilation of the prey species. [ABSTRACT FROM AUTHOR]

In 1982 and 1983, blooms of the planktonic alga Phaeocystis pouchetii were studied in the East Frisian coastal waters off Norderney, FRG. Morphological variability of the colonies, population development, effects on inorganic nutrient and oxygen budget, and the role in the seasonal plankton bloom sequence were investigated. in both years two separate Ph. pouchetii blooms occurred in late spring and early summer that were formed by the ' globosa-type' exclusively. The ' pouchetii-type' was only present during the interval between the first and second blooms in 1982. Growth conditions for Ph. pouchetii seem to be most favourable after a breakdown of a diatom bloom when the silicate reserves have been exhausted, phosphate concentrations are relatively low, but a rich supply of dissolved inorganic nitrogen is available. Contrary to diatom blooms, Ph. pouchetii blooms result in a high production of particulate organic carbon (POC). Another characteristic is the release of great amounts of dissolved organic substances, which cause extensive sea foam formation during the peaks and the subsequent breakdown of the blooms. Due to increased assimilation during mass development and intense disintegration after the breakdown, variations of the oxygen content of the water are significant. Presumably the intensity of blooms has increased in the past decade as indicated by sea foam formation which has actually been excessive in some years. [ABSTRACT FROM AUTHOR]

The polychaete worms Polydora ciliata and P. ligni were investigated with regard to the morphology of their fifth chaetigerous segment, bearing bundles of modified bristles in a special arrangement. The development of these chaetae from late larval to adult stages is described, considering the loss of provisional bristles, the variation of shape caused by the wear and the shedding of old chaetae after losing their function. In addition an epidemic shell disease of the mussel, Mytilus edulis, induced by infestation with P. ciliata is reported. P. ligni was observed to regularly inhabit the inflorescenses of the eelgrass, Zostera marina. The relationships between this plant and P. ligni are discussed. [ABSTRACT FROM AUTHOR]

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