Results 41 to 50 of about 35,458 (292)
Zinc Isotope Ratios as Indicators of Diet and Trophic Level in Arctic Marine Mammals.
PLoS ONE, 2016 Carbon and nitrogen stable isotope ratios of bone collagen are an established method for dietary reconstruction, but this method is limited by the protein preservation.
Klervia Jaouen +2 more
doaj +1 more source
Nitrogen Isotopes in Deep Time [PDF]
, 2021 Nitrogen is an essential nutrient for life, and its sources and cycling have varied over earth history. Stable isotope ratios of nitrogen compounds (expressed as δ15N, in ‰) are preserved in the sedimentary record and track these changes, providing important insights into associated biogeochemical feedbacks.
Mettam, Colin, Zerkle, Aubrey L.
openaire +2 more sources
Frontiers in Marine Science, 2021 Bulk stable nitrogen isotope values of the carbonate-bound organic matrix in bivalve shells (δ15NCBOM) are increasingly used to assess past food web dynamics, track anthropogenic nitrogen pollution and reconstruct hydrographic changes.
Bernd R. Schöne, Qian Huang
doaj +1 more source
Nitrogen Isotopes in the Global Ocean [PDF]
, 2013 Nitrogen is an essential nutrient for life. Its low abundance throughout much of the sunlit surface ocean limits the growth of primary producers that form the base of ocean ecosystems.
Somes, Christopher J. +1 more
core
, 2005 In archaeological dating, the greatest confidence is usually placed upon radiocarbon results of material that can be directly related to a defined archaeological event.
Green, Roger, Petchey, Fiona
core +1 more source
Molecular Oncology, EarlyView.We analyze cisplatin–DNA adducts (CDAs) and double‐strand breaks (DSBs) in a cell‐cycle‐dependent manner. We find that CDAs form similarly across all cell cycle phases. DSBs arise only in S‐phase. CDAs might not directly impair DSB repair, but S‐phase DSB lesions evolve in the presence of CDAs and disrupt repair in G2, also causing radiosensitization ...
Ye Qiu +10 more
wiley +1 more source
Towards a global interpretation of dual nitrate isotopes in surface waters
Journal of Hydrology X, 2019 Modern anthropogenic activities have significantly increased nitrate (NO3−) concentrations in surface waters. Stable isotopes (δ15N and δ18O) in NO3− offer a tool to deconvolute some of the human-made changes in the nitrogen cycle.
J.J. Venkiteswaran +2 more
doaj +1 more source
Elementary Isotopic Analysis: Determination of Nitrogen [PDF]
Nature, 1947 We have recently described an isotopic method for the determination of oxygen1 and carbon2 in organic compounds by using heavy oxygen (O18) and carbon (C13) respectively in conjunction with a mass spectrometer. Using the same method, higher precision is possible in the determination of nitrogen and hydrogen, since N15 and H2 (deuterium) are available ...
A D, KIRSHENBAUM +2 more
openaire +2 more sources
FEBS Open Bio, EarlyView.Abruptly changing from aerobic to anaerobic conditions (sudden anaerobization) induced growth inhibition and a significant increase in intracellular labile ferrous iron in the aerotolerant anaerobe Amphibacillus xylanus. We found that free flavins mediate efficient electron transfer from NADH to ferric iron under anaerobic conditions, suggesting that ...
Shinya Kimata +13 more
wiley +1 more source
Nitrogen Isotope Discrepancy Between Primary Producers and Sediments in an Anoxic and Alkaline Lake
Frontiers in Earth Science, 2021 Nitrogen isotope compositions (δ15N) in sedimentary rocks are extensively used to investigate the biogeochemical nitrogen cycle through geological times.
Pierre Cadeau +7 more
doaj +1 more source