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Showing 1 to 20 of 300 for “"Stable Isotopes"”.
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Stable Isotopes as Tracers for Freshwater Fluxes into the North Atlantic
… properties of oxygen and hydrogen isotopes in watermasses to identify and quantify the freshwater sources to the ocean currents exiting the Arctic into the northern North Atlantic.<br/><br/>Comparison of historical oxygen isotope data from the East Greenland Current system with data …
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Stable isotopes of the thermal springs of the Cape Fold Belt
The Cape Fold Belt is a 250Ma orogenic belt comprised of rocks of the Cape Supergroup, an Ordovician to Devonian sedimentary sequence. The mountainous areas, which reach over 2000m, are composed of the faulted and highly jointed quartzites and sandstones of the Table Mountain Group, which acts as …
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High resolution metabolic flux determination using stable isotopes and mass spectrometry
Cellular physiology is a combination of many different functions that have to be accurately probed individually and then precisely correlated to each other, in order to reveal the language used by the cell to communicate changes from the environment to gene expression and vice versa. Genes are …
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Using stable isotopes to trace the movements of ducks in southern Africa
… This research investigated the utility of the stable isotope technique to trace movements of ducks in southern Africa. I sampled and analysed feathers of ten duck species for stable isotope proportions of Carbon (δ13C), Nitrogen (δ15N) and Hydrogen (δD), from five wetlands (Strandfontein and …
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Reconstructing the diets of southern African farmers: comparing stable isotopes across body tissues
… such as sorghum and millet), multiple tissue isotopes provide valuable insight into diet that cannot be achieved with single tissues, but current models are limited by the lack of isotopic diversity in the data on which they are based. Multi- and bi-variate models are unable to distinguish …
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Paleoclimate and mammal paleocology during the paleocene of North America: insights from stable isotopes.
… fossil mammals. The combination of unique and unstable faunas and globally equable climate resulted in complex ecological and biogeographical patterns among Paleocene mammals that contrast from well-structured patterns that exist today. Latitudinal gradients in Paleocene mammal species richness …
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Stable Isotopes As Intrinsic Markers of Contaminant Dynamics in the Lake Winnipeg Food Web
… the objectives of this study were to use a multi-stable isotope approach (δ15N, δ13C, δ34S and δ2H) to a) identify trophic interactions among fishes and piscivorous birds and b) track the dietary transfer of trace elements. An intensive field program was undertaken in 2009 and 2010. Muscle samples …
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Use of stable isotopes to assess phytoremediation of soils contaminated with cadmium and zinc.
… and only very recently to Cd and Zn using radioisotopes. In the present work, stable isotopes are used for the first time to measure the Cd and Zn available for plant uptake using isotopic exchange principles based on the E and L-values using a contaminated (Great Billings) and a …
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Organocatalytic synthesis of chiral non-racemic aziridines, labelled with 2H, 15N, 13C stable isotopes
… labelled with stable isotopes: 2H, 13C and 15N. The reactions were catalysed by (S)-BINOL derived N-triflylphosphoramide Brønsted acid and stable isotopes were selectively introduced within an aziridine ring with > 95% isotopic enrichment. The desired compounds …
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Climate and habitat reconstruction of hominid sites in northern China with paleosol stable isotopes
… of their environments are needed. Stable isotope geochemistry of paleosols, including carbon isotopes of soil organic matter and pedogenic carbonates, and oxygen isotopes of pedogenic carbonates, can provide evidences for tree:grass ratios, air surface temperature and soil moisture …
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Geochemistry, stable isotopes and fluid inclusion studies of the Otjikoto gold deposit, Central Namibia
The Otjikoto gold deposit is located within the Damara Orogenic Belt which is part of the system of Pan-African mobile belts. The Damara Belt is a northwest trending orogenic belt which formed through sequences of spreading, rifting, subduction and from continental collision between the Congo, …
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The palaeobiology of the non-mammalian cynodonts deduced from bone microstructure and stable isotopes
The biology of six non-mammalian cynodont genera, from basal to more derived forms was examined using bone cross-sectional geometry and histology, as well as isotope analyses. The bone histology of multiple postcrania revealed distinct variations in growth pattern between the genera studied. The …
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Selenium and Chromium Stable Isotopes and the Fate of Redox-Active Contaminants in the Environment
… part of this study, I developed the chromium stable isotope system as a biogeochemical indicator and monitoring tool. After initial work designing the techniques, I measured chromium stable isotope fractionation in laboratory experiments and natural waters. I observed that the products of …
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Elements and stable isotopes as tracers for sleeper shark biology and the Iceland marine food web
Stable isotope studies often rely on only two tracers (usually [delta] 13C and [delta]15N) to study marine ecosystems, which are inherently complex. The ability of elements to act as additional tracers of ecological processes in marine organisms and in a marine food web was investigated. The …
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Tracking diet and movement of Atlantic bluefin tuna (Thunnus thynnus) using carbon and nitrogen stable isotopes
… logistically challenging. Naturally occurring stable isotopes have been used to study diet and movement in many aquatic ecosystems and offer a novel approach for studying these large pelagic fishes.</p><p>Lipids, which have lower carbon isotope values than protein, can affect isotope analyses …
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Unraveling the fingerprints of NOx using stable isotopes: Implications for NOx source partitioning and oxidation chemistry
<p>The nitrogen (N) and oxygen (O) stable isotope composition (δ15N & δ18O) of nitrogen oxides (NOx )may be a useful tool for constraining NOx emission sources as well as for understanding the atmospheric oxidation pathways responsible for its removal if various NOx sources and sink processes …
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Biomarkers (lipids, fatty acids and stable isotopes) to examine diet of the sea urchin Evechinus chloroticus.
… Biomarkers, such as lipids, fatty acids and stable isotopes, were combined to improve the knowledge of feeding habits of wild sea urchins from north-eastern New Zealand, revealing a high contribution from Ecklonia radiata to E. chloroticus diets, but also a contribution from Carpophyllum …
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The potential for using stable isotopes for solving urban geohydrological problems in the Cape Town area
… thesis investigates the potential for using the stable isotopes of hydrogen and oxygen from surface water and shallow aquifer water in solving urban geohydrological problems in the Cape Town metropolitan region. Three different water groups were chosen for detailed analysis, namely groundwater, …
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Determining the Trophic Role of Gulf Menhaden (<i>Brevoortia patronus</i>) Using Carbon and Nitrogen Stable Isotopes
<p>Gulf menhaden (Brevoortia patronus) play multiple roles in the Gulf of Mexico coastal ecosystem as filter feeders and as an important food source for many recreationally and economically important finfish. Gulf menhaden also support a large commercial fishery, and little is known about the …
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