Abstract. In this study, the first fully continuous monitoring of water vapour isotopic composition at Neumayer Station III, Antarctica, during 2-year period from February 2017 to January 2019 is presented. Seasonal and synoptic-scale variations in both stable isotopes H218O HDO are reported, their links key meteorological variables analysed. addition, diurnal cycle isotope summer months (Decem...

The Schoeller model for calculating rate of CO2 production (rCO2) from doubly labeled water (DLW) relies on the assumption that deuterium and oxygen-18 overestimate body water by 4 and 1%, respectively. However, the deuterium-to-oxygen-18 dilution space ratio (DSR) varies considerably, and it is unknown whether this is due to analytical or biological sources. From 161 published values in adult ...

The production of deuterated methane by Methanobacterium thermoautotrophicum in H2O-D2O mixtures was examined by high-resolution mass spectrometry. The hydrogen in the methane arose solely from water and not from hydrogen gas. Hydrogen gas served only as an electron source in methanogenesis. A whole-cell product isotope discrimination of 1.5 favoring hydrogen over deuterium was observed in meth...

The spatial arrangement of polymers in Sitka spruce (Picea sitchensis) was investigated by NMR proton spindiffusion studies, supplemented by deuterium-exchange experiments monitored by FTIR spectroscopy. The FTIR spectra of earlywood sections after vapour-phase exchange with deuterium oxide showed that 43% of the hydroxyl groups were accessible to deuteration. This value is lower than predicted...

Investigation of the metabolism and fate of steroid hormones has been greatly facilitated by isotope stably incorporated into the substance t,o be studied. For many purposes the isotopes of hydrogen are decidedly advantageous in that the chemical synthesis of the labeled steroid can be easily and quickly achieved with a minimum of manipulation. Moreover, since the endogenous pool of the hormone...

Cucurbit[7]uril (CB[7]) encapsulates adamantyl and trimethylsilyl substituents of positively charged guests in dimethyl sulfoxide (DMSO). Unlike water or deuterium oxide, addition a selection alkali alkali-earth cations...

Citation: Medina LE, Taylor CD, Pachiadaki MG, Henríquez-Castillo C, Ulloa O and Edgcomb VP (2017) A Review of Protist Grazing Below the Photic Zone Emphasizing Studies of Oxygen-Depleted Water Columns and Recent Applications of In situ Approaches. Front. Mar. Sci. 4:105. doi: 10.3389/fmars.2017.00105 A Review of Protist Grazing Below the Photic Zone Emphasizing Studies of Oxygen-Depleted Water...

BACKGROUND In developing countries where access to water and food is not guaranteed, women may have to travel long distances or engage in intense physical activities to gather food. This may compromise their water requirements and overall nutritional status. The aim of the study was to determine water turnover, physical activity and body composition among women in Kenya and to describe the diff...

Cerebral blood flow (CBF) quantification is a valuable tool in stroke research. Mice are of special interest because of the potential of genetic engineering. Magnetic resonance imaging (MRI) provides repetitive, noninvasive CBF quantification. Many MRI techniques require the knowledge of the brain-blood partition coefficient (BBPC) for water. Adopting an MRI protocol described by Roberts et al ...

The vibrational dynamics of water around glycine was investigated by using Raman spectroscopy and inelastic neutron scattering. Experiments of deuterated glycine versus deuterium were performed as comparison. The study shows that for glycine, the exchange of proton–deuteron on the active NH+3 side was easy, whereas there was hardly exchange on the CH2 side. Comparing different proportion of gly...