Bulk Sediment and Diatom Silica Carbon Isotope Composition from Coastal Marine Sediments off East Antarctica

Organic carbon occluded in diatom silica is assumed to be protected from degradation in the sediment. δ13C from diatom carbon (δ13C(diatom)) therefore potentially provides a signal of conditions during diatom growth. However, there have been few studies based on δ13C(diatom). Numerous variables can influence δ13C of organic matter in the marine...

Isotopic and microbiological signatures of pyrite-driven denitrification in a sandy aquifer

Denitrification driven by pyrite oxidation can play a major role in the removal of nitrate from groundwater systems. As yet, limited information is available on the interactions between the micro-organisms and aqueous and mineral phases in aquifers where pyrite oxidation is occurring. In this study, we examine the groundwater and sediment...

Emerging applications for traceability systems and implications for consumers

The modified European Food Law (General Food Law) has been emphasizing on the need to increase consumer confidence through implementation of regulatory measures focused on increased traceability in food chain. The implementation of effective traceability systems can provide the basis of communication between actors in the production chain, and...

Lateglacial summer temperatures in the Northwest European lowlands: A chironomid record from Hijkermeer, the Netherlands

Lateglacial environments at Hijkermeer, northwest Netherlands, were reconstructed by means of chironomid, diatom and pollen analyses. Diatom assemblages indicate that Hijkermeer was a shallow, oligo- to mesotrophic lake during this period. Pollen assemblages reflect the typical northwest European Lateglacial vegetation development and provide an...

Application of liquid chromatography-mass spectrometry to measure the concentrations and study the synthesis of short chain fatty acids following stable isotope infusions

A new method involving zinc sulphate deproteinization was developed to study short chain fatty acids (SCFA) production in the colon and subsequent occurrence of SCFA in blood. SCFA were baseline separated in a 30 min cycle using ion-exclusion chromatography and detected by mass spectrometry. Concentrations could be measured down to 10 μM and...

Surface and subsurface expressions of gas seepage to the seabed – examples from the Southern North Sea

Expressions of gas seepage observable within North Sea seismic and acoustic data include seabed pockmarks, seepage plumes in the water column, acoustic blanking, shallow enhanced reflectors, and shallow seismic chimneys. Three areas were selected for a marine survey in

Sixteen hours of fasting differentially affects hepatic and muscle insulin sensitivity in mice

Fasting readily induces hepatic steatosis. Hepatic steatosis is associated with hepatic insulin resistance. The purpose of the present study was to document the effects of 16 h of fasting in wild-type mice on insulin sensitivity in liver and skeletal muscle in relation to 1) tissue accumulation of triglycerides (TGs) and 2) changes in mRNA...

Bioavailability of selenium from fish, yeast and selenate: A comparative study in humans using stable isotopes

Objective: To measure the bioavailability of selenium from cooked and raw fish in humans by estimating and comparing apparent absorption and retention of selenium in biosynthetically labelled fish with labelled selenate and biosynthetically labelled selenium in brewers yeast. Design: The intervention study was a parallel, randomised, reference...

Trace element concentrations and stable lead isotopes in soils as tracers of lead pollution in Graft-De Rijp, the Netherlands

Graft-De Rijp is a former village of whalers, situated twenty-five kilometres north of Amsterdam, the Netherlands. Since the foundation of De Rijp in 1612 a mixture of sludge, manure and town refuse (containing Pb-based household artefacts and Pb-based building materials) was used to raise and fertilise the land. Gasworks, coal storehouses,...

Radiometric trace analysis of lead