A commercial interface coupling liquid chromatography (LC) to a continuous-flow isotope ratio mass spectrometer (IRMS) was used to analyse δ 13 C of dissolved organic carbon (DOC) in natural waters. Stream and soil waters from a farmland plot in a hedgerow landscape were selected for application. Based on wet chemical oxidation of dissolved organics the LCIRMS interface allows on-line injection...

BACKGROUND Resistant starch sources, which are only partially digested in the small intestine, can be used to increase colonic availability of short-chain fatty acids. OBJECTIVE To study the characteristics of the fermentation of resistant starch, the digestion of resistant starch in the small intestine has to be quantified. We compared the metabolic fates of highly digestible cornstarch (DCS...

The distribution of methane sources in Kuwait was mapped through mobile vehicle surveying mole fraction, and by collection air samples at source for subsequent isotopic analysis. Mobile plume identification analysis, reveals that far the largest observed is from landfill sites (δ13CCH4 −58‰), with smaller contributions fossil fuel industry (−50‰), wastewater treatment (−49‰) ruminant animals (s...

One of the outstanding current problems in both geobiology and environmental microbiology is the quantitative analysis of in situ microbial metabolic activities. Techniques capable of such analysis would have wide application, from quantifying natural rates of biogeochemical cycling to identifying the metabolic activity of uncultured organisms. We describe here a method that represents one step...

Arson is a significant problem around the world, and is a crime which results in a low number of convictions. The scene of an arson can be varied, commercial, residential or national park, and recently cases have been identified which were initiated by a lit match. Matches can be recovered from a scene, usually in a burnt condition. The benefit of analysing unburnt matches has been researched p...

Abstract The hydrogen isotopic composition of leaf wax–derived n -alkane (? 2 H ) and oxygen hemicellulose–derived sugar 18 O biomarkers are valuable proxies for paleoclimate reconstructions. Here, we present a calibration study along the Bale Mountains in Ethiopia to evaluate how accurately precisely precipitation is imprinted these biomarkers. -Alkanes sugars were extracted from topsoil sampl...

The purpose of this study was to compare in a laboratory experiment, a suite of methods developed to track viable bacteria during field transport experiments. The criteria for development and selection of these methods included: (1) the ability to track bacteria within the environment from which they were isolated; (2) the lack of any effect upon the viability or the transport characteristics o...

Mediterranean diet has been suggested to explain why coronary heart disease mortality is lower in southern than northern Europe. Dietary habits can be revealed by isotope ratio mass spectrometry (IRMS) measurement of carbon (δ(13)C) and nitrogen (δ(15)N) in biological tissues. To study if diet is associated with human plaque stability, atherosclerotic plaques from carotid endarterectomy on 56 p...