Published in Cellulose
AbstractThe insufficient resolution of conventional methods has long limited the structural elucidation of cellulose and its derivatives, especially for those with relatively low crystallinities or in native cell walls. Recent 2D/3D solid-state NMR studies of 13C uniformly labeled plant biomaterials have initiated a re-investigation of our existing...
2017
Published in Plant and Soil
Background and aimsRhizosphere priming occurs when plant belowground carbon (C) allocation influences the rate of soil organic matter (SOM) decomposition. We investigated the effects of priming and plant-mediated cover crop decomposition on agroecosystem C and nitrogen (N) dynamics.MethodsUsing C stable isotopes, we tracked C and N from corn, clove...
Published in Plant & cell physiology
The use of carbon isotope abundance (δ(13)C) to assess plant carbon acquisition and water use has significant potential for use in crop management and plant improvement programs. Utilizing Phaseolus vulgaris L. as a model system, this study demonstrates the occurrence and sensitivity of carbon isotope fractionation during the onset of abiotic stres...
Published in Oecologia
Nitrogen (N) losses constrain rates of plant carbon dioxide (CO2) uptake and storage in many ecosystems globally. N isotope models have been used to infer that ~30 % of terrestrial N losses occur via microbial denitrification; however, this approach assumes a small isotope effect associated with N leaching losses. Past work across tropical/sub-trop...
Published in Lipids
Finger or heel-pricked blood sampling for fatty acid analysis is suitable especially in newborn infants where blood sampling is difficult and phlebotomy for research can be unethical. The aim of this study was to evaluate dried blood long chain polyunsaturated fatty acids (LC-PUFA) stability during storage at −28 °C. We collected 12 blood cord samp...
The hydrogen isotopic composition (δD or (D/H) value) of molecular biomarkers preserved in sedimentary archives is increasingly used to provide clues about the evolution of past climatic conditions. The rationale is that intact biomarkers retain isotopic information related to the climatic conditions that prevailed at the time of their synthesis. S...
Published in Solid state nuclear magnetic resonance
The successful synthesis and solid state NMR characterization of silica-based organic-inorganic hybrid materials is presented. For this, collagen-like peptides are immobilized on carboxylate functionalized mesoporous silica (COOH/SiOx) materials. A pre-activation of the silica material with TSTU (O-(N-Succinimidyl)-N,N,N',N'-tetramethyluronium tetr...
Published in Oecologia
Changes in the 12C/13C ratio (expressed as δ13C) of soil organic C (SOC) has been observed over long time scales and with depth in soil profiles. The changes are ascribed to the different reaction kinetics of 12C and 13C isotopes and the different isotopic composition of various SOC pool components. However, experimental verification of the subtle ...
Published in Journal of magnetic resonance (San Diego, Calif. : 1997)
2D NMR (1)H-X (X=(15)N or (13)C) HSQC spectra contain cross-peaks for all XHn moieties. Multiplicity-edited(1)H-(13)C HSQC pulse sequences generate opposite signs between peaks of CH(2) and CH/CH(3) at a cost of lower signal-to-noise due to the (13)C T(2) relaxation during an additional 1/(1)JCH period. Such CHn-editing experiments are useful in as...
