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Oxygen Isotopes (1):
Recent article
Oxygen Isotopes
Abstract
We show that continental warming of about 5 °C preceded the CIE in the Bighorn Basin, Wyoming. Our evidence, based on oxygen isotopes in mammal teeth (which reflect temperature-sensitive fractionation processes) and other proxies, reveals a marked temperature increase directly below the CIE, and...
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PMID: 20962843
PDF is available here.
PDF is available here.
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Abstract
Nitrogen (N) retention and transformation in the Szczecin Lagoon, southern Baltic Sea, were studied by means of budget calculations and stable isotope data of dissolved and particulate matter. Two stations, one located at the main outlet of the lagoon (Swina Strait) and the other 100 km to the south...
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PMID: 20672205
PDF is available here.
PDF is available here.
Abstract
In paleohydrogeological studies, the geochemical and isotope geochemical composition of fracture calcites can be utilised to gain information about the evolution of the composition of deep groundwaters in crystalline bedrock. The aim of our study was to investigate the latest hydrogeochemical evolut...
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PMID: 20665300
PDF is available here.
PDF is available here.
Abstract
This study presents selected results, applying environmental tracers to investigate lake water-groundwater interactions at two study sites located in Lusatia, Germany. The focus of the investigations were two meromictic pit lakes and their adjacent aquifers. In order to follow hydrodynamic processes...
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PMID: 20645204
PDF is available here.
PDF is available here.
Abstract
We used a combination of (17)O NMR methods at a high magnetic field with first-principles calculations in order to characterize the oxygen sites in a series of hydroxylated sodium phosphate compounds, namely the hydrogen pyrophosphate Na(2)H(2)P(2)O(7) and the hydrogen orthophosphates NaH(2)PO(4), N...
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PMID: 20559592
PDF is available here.
PDF is available here.
Journal of Nutrition (140)8 2010
Abstract
Our primary aim in this study was to validate cross-sectional time series (CSTS) and multivariate adaptive regression splines (MARS) models based on observable participant characteristics, heart rate (HR), and accelerometer counts (AC) for prediction of minute-by-minute EE, and hence 24-h total EE (...
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PMID: 20573939
PDF is available here.
PDF is available here.
Abstract
In many nitrate (NO(3)(-)) source partitioning studies, the delta(18)O value for NO(3)(-) produced from nitrification is often assumed to reflect the isotopic compositions of environmental water (H(2)O) and molecular oxygen (O(2)) in a 2:1 ratio. Most studies that have measured or observed this micr...
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PMID: 20550183
PDF is available here.
PDF is available here.
Abstract
We show that the Turkana Basin, Kenya--today one of the hottest places on Earth--has been continually hot during the past 4 million years. The distribution of (13)C-(18)O bonds in paleosol carbonates indicates that soil temperatures during periods of carbonate formation were typically above 30 degre...
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PMID: 20534500
PDF is available here.
PDF is available here.
Abstract
We report the application of a new type of geochemical measurement to bioapatite, a "clumped-isotope" paleothermometer, based on the thermodynamically driven preference for (13)C and (18)O to bond with each other within carbonate ions in the bioapatite crystal lattice. This effect is dependent on te...
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PMID: 20498092
PDF is available here.
PDF is available here.
Medical Oncology (27)2 2010
Abstract
We undertook comparative proteomics for identification of gastric carcinoma biomarkers using pooled laser capture microdissected GA cells and matched nonmalignant gastric mucosa epithelial cells. The method involved separation of total proteins by 1D SDS-PAGE, trypsin digestion, and postdigest (18)O...
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PMID: 19330469
PDF is available here.
PDF is available here.
Phytochemistry (71)8-9 2010
Abstract
We modified the widely-accepted "standard" three-step extraction method for isolating cellulose from plants by changing the order of the steps for hemicellulose and lignin removal (solubilisation with concentrated NaOH and oxidation with acetic acid-containing NaClO(2), respectively) so that cellulo...
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PMID: 20362306
PDF is available here.
PDF is available here.
Abstract
We report a mass spectrometry-based strategy for quantitative analysis of cell surface membrane proteome changes. The strategy includes enrichment of surface membrane proteins using a membrane-impermeable chemical probe followed by stable isotope (18)O labeling and LC-MS analysis. We applied this st...
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PMID: 20380418
PDF is available here.
PDF is available here.
Tree Physiology (30)5 2010
Abstract
We measured ring widths and isotopic abundances of carbon, oxygen and hydrogen (delta(13)C, delta(18)O and delta(2)H) from the latewood of tree rings of pedunculate oak (Quercus robur L.) in its distributional northern limit in Southern Finland. Ring width was observed to be related to precipitation...
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PMID: 20357343
PDF is available here.
PDF is available here.
Tree Physiology (30)5 2010
Abstract
We measured ring widths and isotopic abundances of carbon, oxygen and hydrogen (delta(13)C, delta(18)O and delta(2)H) from the latewood of tree rings of pedunculate oak (Quercus robur L.) in its distributional northern limit in Southern Finland. Ring width was observed to be related to precipitation...
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PMID: 20357343
PDF is available here.
PDF is available here.
Inorganic Chemistry (49)8 2010
Abstract
Oxidative transformations using molecular oxygen are widespread in nature but remain a major challenge in chemical synthesis. Limited mechanistic understanding presents the main obstacle to exploiting O(2) in "bioinspired" industrial processes. Isotopic methods are presently being applied to charact...
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PMID: 20380467
PDF is available here.
PDF is available here.
Tree Physiology (30)3 2010
Abstract
We used stable carbon isotope ratios (delta(13)C) of annual rings from red pine trees (Pinus resinosa Ait.) as an index of intrinsic water use efficiency (iWUE), the ratio of photosynthetic carbon assimilation (A) to stomatal conductance (g(s)), to better understand how differences in physiological...
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PMID: 20038504
PDF is available here.
PDF is available here.
Abstract
Abstract
We report here state-to-state differential and integral cross sections for several O + O(2) isotope-exchange reactions obtained by dynamically exact quantum scattering calculations at collision energies relevant to atmospheric conditions. These reactions are shown to be highly nonstatistical, eviden...
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PMID: 20080718
PDF is available here.
PDF is available here.
Abstract
The mean difference between PAL(cell) and PAL(ref) was small (0.014) with narrow limits of agreement (2SD = 0.30). Compared with PAL(ref), the mean difference was also small for PAL(quest1) and PAL(quest2) (0.004 and 0.07, respectively); however, the limits of agreement were wider (PAL(quest1), 2SD...
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PMID: 20118036
PDF is available here.
PDF is available here.
Abstract
We demonstrate that untreated diabetes mellitus results in distinct combinations, or signatures, of the hydrogen (delta2H) and oxygen (delta18O) isotope ratios in body water. Additionally, we show that the delta2H and delta18O values of body water are correlated with increased water flux, suggesting...
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PMID: 20657736
PDF is available here.
PDF is available here.
Abstract
Abstract
A sensitive laser spectrometer, named IRIS (water isotope ratio infrared spectrometer), was developed for the in situ detection of the isotopic composition of water vapour in the upper troposphere and the lower stratosphere. Isotope ratio measurements can be used to quantify troposphere-stratosphere...
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PMID: 19670069
PDF is available here.
PDF is available here.
Abstract
We report the first (17)O quadrupole-central-transition (QCT) NMR spectroscopic study of protein-ligand complexes in solution. This work shows that it is possible to obtain high resolution (17)O NMR spectra for (17)O-labeled ligands bound to proteins. At high magnetic fields such as 21.14 T, this (1...
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PMID: 19764760
PDF is available here.
PDF is available here.
Abstract
Sediments containing Ardipithecus ramidus were deposited 4.4 million years ago on an alluvial floodplain in Ethiopia's western Afar rift. The Lower Aramis Member hominid-bearing unit, now exposed across a > 9-kilometer structural arc, is sandwiched between two volcanic tuffs that have nearly identic...
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PMID: 19810191
PDF is available here.
PDF is available here.
Ecological Applications (19)6 2009
Abstract
We used the stable oxygen isotope composition of otoliths (delta18O(oto)) to reconstruct the ambient temperature history of Eastern Scotian Shelf cod from 1970 to 2000 in order to determine whether the stock experienced the temperature decline or shifted their distribution to avoid it. To correct de...
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PMID: 19769098
PDF is available here.
PDF is available here.
Abstract
The compositions of commercially available fruit juices on the Slovenian and Cypriot markets have been compared and checked against the corresponding declarations on the packaging. Values of delta(13)C in the pulp, sugars, and ethanol (produced by fermentation and distillation) have been obtained by...
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PMID: 19586026
PDF is available here.
PDF is available here.
Abstract
We report ClO4- stable isotope data (delta37Cl, delta18O, and delta17O), along with other supporting chemical and isotopic environmental tracer data, to document groundwater ClO4 contamination sources and history in parts of Long Island, New York. Sampled groundwaters were oxic and ClO4- apparently...
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PMID: 19731653
PDF is available here.
PDF is available here.
Abstract
A new method that uses immobilized trypsin concomitant with ultrasonic irradiation results in ultrarapid digestion and more thorough (18)O labeling for quantitative protein comparisons. The method was reproducible and provided effective digestions within <1 min with lower amounts of enzyme, compared...
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PMID: 19555078
PDF is available here.
PDF is available here.
Abstract
We measured the delta18Op of a variety of known phosphate sources, including fertilizers, semiprocessed phosphorite ore, particulate aerosols, detergents, leachates of vegetation, soil, animal feces, and wastewater treatment plant effluent. We found a considerable range of delta18Op, values (from +8...
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PMID: 19708340
PDF is available here.
PDF is available here.
Biochemistry (Washington) (48)26 2009
Abstract
We report here the X-ray crystallographic structures of two variants (W39F and Y181F) involved in the binding of bicarbonate ion in the non-catalytic site and an active-site variant (D44N) that is incapable of forming a strong zinc ligand. The alteration of Trp39 to Phe increases the apparent K(i) f...
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PMID: 19459702
PDF is available here.
PDF is available here.
Abstract
We must now rethink past estimations of population social structure in Levantine coastal Medieval cities during the Crusader period. Am J Phys Anthropol 2009. (c) 2009 Wiley-Liss, Inc....
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PMID: 19530140
PDF is available here.
PDF is available here.
Abstract
Previous anthropological investigations at Trentholme Drive, in Roman York identified an unusual amount of cranial variation amongst the inhabitants, with some individuals suggested as having originated from the Middle East or North Africa. The current study investigates the validity...
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PMID: 19530143
PDF is available here.
PDF is available here.
An isotopic perspective on the transport of Byzantine mining camp laborers into southwestern Jordan.
Abstract
The Byzantine Empire managed a complex administrative network that controlled the mining and processing of natural resources from within its boundaries. Scholars relying upon archeological and textual evidence debate the level of imperial involvement in these ventures, particularly i...
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PMID: 19425090
PDF is available here.
PDF is available here.
Abstract
We tested the hypotheses that relative activity of the less efficient alternative oxidase (AOX) path changes with diurnal temperature changes, and thus changes carbon use efficiency with temperature. The activities of the alternative and cytochrome oxidase (COX) paths in plant tissues of three speci...
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PMID: 19210639
PDF is available here.
PDF is available here.
Abstract
We present the largest quantitative proteomics study to date on the short term effects of VEGF on human umbilical vein endothelial cells by 18O/16O labeling. Current statistical models based on normality and variance homogeneity were found unsuitable to describe the null hypothesis in a large scale...
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PMID: 19181660
PDF is available here.
PDF is available here.
Abstract
We investigate cultural heterogeneity at the Loa site of Caspana through analyses of strontium and oxygen isotopes, cranial modification styles, and mortuary behavior, integrating biological aspects of identity, particularly geographic origins, with cultural aspects of identity manifested in body mo...
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PMID: 19051258
PDF is available here.
PDF is available here.
Abstract
We asked if acid-catalyzed back exchange could interfere with quantitation and whether the reaction itself could be used as method for introducing (18)O label into peptides. Several synthetic peptides were dissolved in dilute acid containing 50% (v/v) H(2)(18)O and incubated at room temperature. Ali...
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PMID: 19243188
PDF is available here.
PDF is available here.
Abstract
In order to generate a local daughter scale from the material defining the international delta13C and delta18O stable isotope ratio scales (NBS19-calcite),1,2 the carbon and oxygen must be liberated to the gas phase, usually as CO2, using acid digestion of the calcite with H3PO4. It is during this c...
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PMID: 19222031
PDF is available here.
PDF is available here.
Tree Physiology (29)2 2009
Abstract
We used the natural abundance of stable isotopic ratios of hydrogen and oxygen in soil (0.05-3 m depth), plant xylem and precipitation to determine the seasonal changes in sources of soil water uptake by two native encroaching woody species (Pinus ponderosa P. & C. Lawson, Juniperus virginiana L.),...
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PMID: 19203941
PDF is available here.
PDF is available here.
Abstract
Proton- and neutron-induced activation products in the components of a high-pressure [18O]H2O target vessel used for the production of 18F− in a medical cyclotron have been identified using high resolution gamma spectrometry. The activities leached from the target vessel into the [18O]H2O during ir...
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PMID: 19111472
PDF is available here.
PDF is available here.
Traceability and Discrimination among Differently Farmed Fish: A Case Study on Australian Murray Cod
Abstract
The development of traceability methods to distinguish between farmed and wild-caught fish and seafood is becoming increasingly important. However, very little is known about how to distinguish fish originating from different farms. The present study addresses this issue by attemptin...
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PMID: 19072224
PDF is available here.
PDF is available here.
Abstract
We propose naphthalene 1,2-oxide as the primary product of AaP-catalyzed oxygenation of naphthalene. Using (18)O-labeled hydrogen peroxide, the origin of the oxygen atom transferred to naphthalene was proved to be the peroxide that acts both as oxidant (primary electron acceptor) and oxygen source....
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PMID: 18815784
PDF is available here.
PDF is available here.
Faraday Discussions (141) 2009
Abstract
Water 2H and 17O spin relaxation is used to study water dynamics in the hydration layers of two small peptides, two globular proteins and in living cells of two microorganisms. The dynamical heterogeneity of hydration water is characterized by performing relaxation measurements over a wide temperatu...
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PMID: 19227355
PDF is available here.
PDF is available here.
Abstract
Our field applications showed that the method can be applied easily and quickly, but the error in the estimated infiltration rate can be up to 20%. The estimated infiltration into the recent sewer in Torraccia is 14% and can be considered negligible given the precision of the method, while the old s...
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PMID: 19657168
PDF is available here.
PDF is available here.
Abstract
We applied dual isotope analysis of NO(3)(-) to determine the dominant sources and processes that affect NO(3)(-) concentrations in six stream/river watersheds of different land uses. Samples were collected monthly at a range of flow conditions for 15 mo during 2004-05 and analyzed for NO(3)(-) conc...
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PMID: 19398512
PDF is available here.
PDF is available here.
Abstract
We studied O exchange during N(2)O formation in soil, using a novel combination of (18)O and (15)N tracing. Twelve soils were studied, covering soil and land-use variability across Europe. All soils demonstrated the significant presence of O exchange, as incorporation of O from (18)O-enriched H(2)O...
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PMID: 19061209
PDF is available here.
PDF is available here.
Abstract
We measured delta(18)O in standard materials (IAEA 601, IAEA 602, Merck cellulose) and soils (organic and mineral soils) in order to determine a suitable pyrolysis temperature for soil analysis. We consider a pyrolysis temperature suitable when the yield of signal intensity (intensity of mass 28 per...
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PMID: 19089856
PDF is available here.
PDF is available here.
Abstract
With the conjunction of tunable diode laser absorption spectroscopy technology (TDLAS) and the open long optical path technology, the system designing scheme of CO2 on-line monitoring based on near infrared tunable diode laser absorption spectroscopy technology was discussed in detail, and the instr...
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PMID: 19385195
PDF is available here.
PDF is available here.
Neurology India (57)4 2009
Abstract
Abstract
The influence of the rate nu and the share of freezing water g on the separation of hydrogen D and oxygen 18O has been studied by mass spectromertry. Evidence was obtained supporting the well known facts that, upon freezing of water: (1) the concentration of D in ice is higher than in water; (2) the...
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PMID: 19894621
PDF is available here.
PDF is available here.
Abstract
Orotidine-5'-monophosphate decarboxylase (OMP decarboxylase, ODCase) catalyzes the decarboxylation of orotidine-5'-monophosphate (OMP) to uridine-5'-monophosphate (UMP). Despite extensive enzymological, structural, and computational studies, the mechanism of ODCase remains incompletely characterized...
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PMID: 19039361
PDF is available here.
PDF is available here.
Inorganic Chemistry (47)24 2008
Abstract
This Communication addresses a long-standing problem: the exact vibrational assignments of the low-energy modes of the Fe-N-O subunit in six-coordinate ferrous heme nitrosyl model complexes. This problem is addressed using nuclear resonance vibrational spectroscopy (NRVS) coupled to (15)N(18)O isoto...
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PMID: 18998631
PDF is available here.
PDF is available here.
Biochemical Society transactions (36)Pt 6 2008
Abstract
SOEs (sulfite-oxidizing enzymes) are physiologically vital and occur in all forms of life. During the catalytic cycle, the five-co-ordinate square pyramidal oxo-molybdenum active site passes through the Mo(V) state, and intimate details of the structure can be obtained from variable frequency pulsed...
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PMID: 19021510
PDF is available here.
PDF is available here.
Abstract
We tested the hypothesis that ad libitum food intake shows corrective responses over periods of 1-5 d.
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PMID: 19064509
PDF is available here.
PDF is available here.
Abstract
Abstract
We report the discovery of exceptionally large biogenic magnetite crystals in clay-rich sediments spanning the Paleocene-Eocene Thermal Maximum (PETM) in a borehole at Ancora, NJ. Aside from previously described abundant bacterial magnetofossils, electron microscopy reveals novel spearhead-like and...
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PMID: 18936486
PDF is available here.
PDF is available here.
Plant, Cell & Environment (31)11 2008
Abstract
Leaf gas exchange and leaf water (18)O enrichment (Delta(18)O(L)) were measured in three Clusia species under field conditions during dry and wet seasons and in Miconia argentea during the dry season in the Republic of Panama. During the dry season, all three Clusia species used crassulacean acid me...
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PMID: 18684241
PDF is available here.
PDF is available here.
Abstract
We report on the use of compound-specific isotope analysis of RDX to obtain delta(15)N and delta(18)O enrichment factors during biodegradation in batch cultures. A new preparation method has been developed based on RDX purification using thin-layer chromatography. RDX is then subjected to an element...
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PMID: 19031859
PDF is available here.
PDF is available here.
Abstract
We applied the dual isotope system (delta(34)S-delta(18)O--SO4(2-)) to investigate the relevance of bacterial sulfate reduction (BSR) for natural biodegradation in an anaerobic, sulfate rich aquifer contaminated with petroleum hydrocarbons. Isotope fractionation parameters were determined in column...
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PMID: 19031864
PDF is available here.
PDF is available here.
Abstract
We report for the first time stable isotope composition of N2O emitted from Antarctic sea animal colonies (including penguin, seal and skua colonies) and normal tundra soils using in situ field observations and laboratory incubations, and we have analyzed the effects of sea animal excrement depositi...
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PMID: 18932270
PDF is available here.
PDF is available here.