Holocene ice marginal fluctuations of the Qassimiut lobe in South Greenland

Knowledge about the Holocene evolution of the Greenland ice sheet (GrIS) is important to put the recent observations of ice loss into a longer-term perspective. In this study, we use six new threshold lake records supplemented with two existing lake records to reconstruct the Holocene ice marginal fluctuations of the Qassimiut lobe (QL) – one of the most dynamic parts of the GrIS in South Greenland. Times when the ice margin was close to present extent are characterized by clastic input from the glacier meltwater, whereas periods when the ice margin was behind its present day extent comprise organic-rich sediments. We find that the overall pattern suggests that the central part of the ice lobe in low-lying areas experienced the most prolonged ice retreat from ~9–0.4 cal. ka BP, whereas the more distal parts of the ice lobe at higher elevation re-advanced and remained close to the present extent during the Neoglacial between ~4.4 and 1.8 cal. ka BP. These results demonstrate that the QL was primarily driven by Holocene climate changes, but also emphasises the role of local topography on the ice marginal fluctuations

Blepharisma intermedium Padmavathi, 1959 (Ciliophora: Heterotrichida) from Al-Hassa Inland Hypersaline Oasis in Saudi Arabia

1) Zoology Department, College of Science, King Saud University, Saudi Arabia; 2) Department of Cell Biology, Zoological Institute, University of Copenhagen, Copenhagen, Denmark; 3Private Laboratory, Faaborg, DenmarkA medium-sized, pink heterotrich ciliate was found in hypersaline ponds in the inland Al-Hassa Oasis. The morphology and infraciliature were studied in vivo, and in silver carbonate and protargol impregnated cells. The organism has a slender filiform macronucleus without terminal swellings. The morphology and morphometric data agree largely with the original description of Blepharisma intermedium Padmavathi, 1959; however, the present organism has fewer kineties and both kinetosomes of somatic dikinetids are ciliated. The findings are discussed on the basis of a summary made from available data on other Blepharisma species with a filiform macronucleus

In situ Characterisation of Practical Heterogeneous Catalysts

In situ methods are considered as a curiosity within the standard methodology of practical catalyst characterization. The methods are not commercially available and need to be adapted and validated for each specific problem. The great advantage of these methods is, however, that they deliver immediately relevant characteristics of the working state of a heterogeneous catalyst and allow justified structure-function relations to be deduced. To achieve this it is essential that the experiments are planned and conducted in such away that the proven to be active state of the catalyst is investigated. This can only be ascertained if simultaneous kinetic and spectroscopic data are acquired. The contribution lists a selection of methods with their main characteristics that allows to choose from the wide spectrum of information those that are most relevant for the given problem. A tabulated selection of case studies from the literature gives some insight in the current practice