Arsenosugar phospholipids and arsenic hydrocarbons in two species of brown macroalgae

Fourteen arsenolipids, including 11 new compounds, were identified and quantified in two species of brown algae, Wakame (Undaria pinnatifida) and Hijiki (Hizikia fusiformis), by high resolution mass spectrometry, high performance liquid chromatography–mass spectrometry and gas chromatography–mass spectrometry. Both algal species contained arsenosugar-phospholipids as the major type of arsenolipid, and arsenic-hydrocarbons were also significant components, particularly in Hijiki. The origin of the various arsenolipids, and the possible significance of their relative quantities, is briefly discussed

The Effects of Different Canopy Covers on the Herb Layer in the Forest-Steppes of the Grazer Bergland (Eastern Alps, Austria)

The submontane belt of the eastern Alps is dominated by beech forests. However, on rocky and steep south-facing slopes, small vegetation mosaics have developed, which, to a certain degree, are similar to the Pannonian forest-steppes. In spite of their unique conservation importance and threatened status, they have received relatively little scientific attention. In this study we analyzed the spatial pattern of such mosaics. More specifically, our objective was to find out how canopy cover value inf luences the species composition of the herb layer. According to our results, canopy cover of Pinus sylvestris has a rather limited effect on the herb layer composition and species richness. Thus, in the studied canopy cover range (ca. 5–75% canopy cover), most species occurred under all canopy cover gr ades. This is presumably a result of the canopy char- acteristics and branching pattern of P. s y l v e s t r i s : it can be assumed that the physical conditions of the canopy and intercanopy patches are somewhat similar. This is in sharp contrast with the Pannonian forest-steppes dominated by Quercus pubescens . We conclude that, even though the cessation of traditional land-use may not result in a rapid change of the composition in eastern Austrian forest-steppes, every effort must be made to conserve these valuable habitats

An Impacting Descent Probe for Europa and the other Galilean Moons of Jupiter

We present a study of an impacting descent probe that increases the science return of spacecraft orbiting or passing an atmosphere-less planetary body of the solar system, such as the Galilean moons of Jupiter. The descent probe is a carry-on small spacecraft (< 100 kg), to be deployed by the mother spacecraft, that brings itself onto a collisional trajectory with the targeted planetary body in a simple manner. A possible science payload includes instruments for surface imaging, characterisation of the neutral exosphere, and magnetic field and plasma measurement near the target body down to very low-altitudes (~1 km), during the probe's fast (~km/s) descent to the surface until impact. The science goals and the concept of operation are discussed with particular reference to Europa, including options for flying through water plumes and after-impact retrieval of very-low altitude science data. All in all, it is demonstrated how the descent probe has the potential to provide a high science return to a mission at a low extra level of complexity, engineering effort, and risk. This study builds upon earlier studies for a Callisto Descent Probe (CDP) for the former Europa-Jupiter System Mission (EJSM) of ESA and NASA, and extends them with a detailed assessment of a descent probe designed to be an additional science payload for the NASA Europa Mission.Comment: 34 pages, 11 figure

Some aspects of man-made contamination on ULF measurements

An analysis of the man made contamination on ULF measurements in highly populated areas has been conducted at several suitably chosen sites in Western Europe. The experimental results show common characteristics at different stations with clear evidence for an additional working day contamination with respect to weekends. These effects more clearly emerge in the vertical component that is less influenced by natural signals. A similar analysis conducted at Terra Nova Bay does not reveal any clear evidence for man made disturbances on Antarctic measurements.&lt;br&gt;&lt;br&gt; &lt;b&gt;Key words.&lt;/b&gt; (Magnetospheric physics, instruments and techniques; Solar wind-magnetosphere interaction) (Geomagnetism and paleomagnetism time variations, diurnal to secular

Determination of water and lipid-soluble arsenic compounds in the commercial edible seaweed Hijiki (Hizikia fusiforme)

Se presentan los resultados obtenidos en los estudios de especiación de arsénico realizados sobre el alga comestible Hijiki. Los análisis se realizaron a través de métodos analíticos desarrollados en la UPM (España) y en la Universidad de Graz (Austria). La determinación de especies hidrosolubles se realizó mediante HPLC-(UV)-HG-AFS, previa extracción mediante MAE con agua desionizada. Por otro lado, la identificación y cuantificación de arsenolípidos se llevó a cabo mediante HPLC-ICPMS/ESMS, previa extracción con cloroformo:metanol y purificación mediante SPE