RATIONALE The hydrogen and oxygen isotopic analyses (δ(2)H and δ(18)O values) of water trapped within speleothem carbonate (fluid inclusions) have traditionally been conducted utilizing dual-inlet isotope ratio mass spectrometry (IRMS) or continuous-flow (CF)-IRMS methods. The application of cavity ring-down spectroscopy (CRDS) to the δ(2)H and δ(18)O analysis of water in fluid inclusions has b...

Acetic acid is the main ingredient of vinegar, and the worth of vinegar often depends on the fermentation of raw materials. In this study, we have developed a simple and rapid method for discriminating the fermentation of the raw materials of vinegar by measuring the hydrogen and carbon isotope ratio of acetic acid using head space solid-phase microextraction (HS-SPME) combined with gas chromat...

Measurement of total primary production using C incorporation is a widely established tool. However, these bulk measurements lack information about the fate of fixed carbon: the production of major cellular compounds (carbohydrates, amino acids, fatty acids, and DNA/RNA) is affected by for instance nutrient availability as their C:N:P requirements differ. Here, we describe an approach to combin...

Cosmetics have a long history in China, but their origins remain unclear. Cosmetic industry potentially originated the Spring and Autumn Period (770–476 bce), little is known about early manufacture use of cosmetics. The Liujiawa site, located on southern edge Loess Plateau northern was late capital ancient Rui state to mid-Spring Period. During excavation, sealed small exquisite container with...

A microcosm study was conducted to investigate the degradation of mono- and polyaromatic hydrocarbons under in situ-like conditions using alluvial sediments from the site of a former cokery. Benzene, naphthalene, or acenaphthene were added to the sediments as (13)C-labeled substrates. Based on the evolution of (13)C-CO(2) determined by gas chromatography isotope-ratio mass spectrometry (GC-IRMS...

Compound-speci®c D values recorded by means of gas chromatography±thermal conversion±isotope ratio mass spectrometry (GC±TC±IRMS) of the biomarker n-alkane (n-tricosane; n-C23) representative of the dominant Sphagnum species in a 40 cm peat pro®le from Bolton Fell Moss, Cumbria, UK, correlate with vegetation changes in the past >200 years (age depth model based on Pb dating). The bog vegetation...

In order to delineate the origin of soil fatty acids, crop soil samples have been incubated for 21 days in vitro either with unlabelled or 13C-labelled glucose. Analyses of C14-C32 n-alkanoic acids from monocarboxylic acid fractions, as methyl esters, by gas chromatography-combustion-isotope ratio monitoring mass spectrometry (GC-C-IRMS) show that C14, C16 and C18 n-alkanoic acids are 13C-label...

OBJECTIVES HIV-positive people have increased risk of infection-related malignancies (IRMs) and infection-unrelated malignancies (IURMs). The aim of the study was to determine the impact of aging on future IRM and IURM incidence. METHODS People enrolled in EuroSIDA and followed from the latest of the first visit or 1 January 2001 until the last visit or death were included in the study. Poiss...

We pilot tested a novel human factors-informed concept to identify infectious risk moments (IRMs) that occur with high frequency during routine intensive care. Following 30 observation-hours, 28 potential IRMs related to hand hygiene, gloves, and objects were expert rated. A comprehensive IRM inventory may provide valuable taxonomy for research, training, and intervention.