In recent years stable isotopes of metallic and semi-metallic elements have become popular as tracers in studies of nutrition and metabolism. There are several recent reviews on the use of stable isotopes of the mineral elements (Janghorbani & Young, 1980; Janghorbani et af . 1985). The orientation of these reviews has tended toward neutron-activation analysis in conjunction with the faecal iso...

HarvestPlus Technical Monographs are designed to provide a forum for HarvestPlus research outputs. Technical Monographs can be of two kinds: • state-of-the-art reviews that help to establish and define HarvestPlus research questions or • " gold standard " procedures to be followed in HarvestPlus research. HarvestPlus technical monographs are written by recognized experts in the field and are ex...

In recent years stable isotopes of metallic and semi-metallic elements have become popular as tracers in studies of nutrition and metabolism. There are several recent reviews on the use of stable isotopes of the mineral elements (Janghorbani & Young, 1980; Janghorbani et af . 1985). The orientation of these reviews has tended toward neutron-activation analysis in conjunction with the faecal iso...

Inherent difficulties of tracking and observing organisms in the field often leave researchers with no choice but to conduct behavioral experiments under laboratory settings. However, results of laboratory experiments do not always translate accurately to natural conditions. A fundamental challenge in ecology is therefore to scale up from small area and short-duration laboratory experiments to ...

Gray seals (Halichoerus grypus) have been rapidly recolonizing the Northeast US coast, eliciting concern from the fishing industry. However, the ecological effect of this recovery is still unknown and as such, research is needed to better understand how the diet composition of gray seals in US waters will contribute to the ecological impact. While previous research on seal diets has focused on ...

A new method for the measurement of calcium isotope ratios and total calcium, using a double focusing sector field inductively coupled plasma mass spectrometry (ICP-MS) instrument equipped with a shielded torch, is presented. The method was applied for the measurement of the Ca/Ca, Ca/Ca and Ca/Ca ratios and total calcium by isotope dilution in urine samples from two different nutritional exper...

RATIONALE It was recently shown that the presence of CO2 affects the stable isotope (δ2 H and δ18 O values) analysis of water vapor via Wavelength-Scanned Cavity Ring-Down Spectroscopy. Here, we test how much CO2 is emitted from soil samples and if the CO2 in the headspace influences the isotope analysis with the direct equilibration method by Off-Axis Integrated Cavity Output Spectroscopy (OA-...