• Stable isotopes of carbon (δ13C), sulfur (δ34S), oxygen (δ18O), hydrogen (δ2H), nitrogen (δ15N), and radioactive isotope of hydrogen (tritium) have been applied in combination with conventional techniques (chemical) to investigate Karachi coastal water pollution due to Layari and Malir rivers, which mainly carry the domestic and industrial wastewater of Karachi Metropolitan. (intechopen.com)
  • collected from nonpolluted northwest coast was higher as compared to the average δ15N contents (8.0‰ air) of Ulva from the Manora Channel, suggesting that nitrogen isotopic ratios of Ulva spp. (intechopen.com)
  • This study is the first of its kind to analyse carbon, nitrogen and sulphur stable isotope data from skeletons of the eleventh-seventeenth centuries in Portugal. (springer.com)
  • This fractionation enables the use of stable nitrogen isotopes (δ 15 N) to infer trophic level, and high δ 15 N recorded in bone collagen usually indicates high-protein diets (Sponheimer et al. (springer.com)
  • In those iron-poor places, there's plenty of everything else that phytoplankton, the base of the food web, need to grow - sunlight, carbon, fixed nitrogen, water. (sc.edu)
  • It forms from nitrogen high in the sky at a certain rate on today's Earth. (icr.org)
  • We compared the macronutrient composition of diets inferred from stable carbon and nitrogen isotopes in polar bear guard hair (primarily representing summer/fall diet) during periods when bears had low and high survival 2004-2016, between bears that summered on land versus pack ice, and between bears occupying different regions of the Alaskan and Canadian Beaufort Sea. (usgs.gov)
  • The mineralogy, major and trace elements, Sr isotopes, volatiles, and nitrogen characteristics of the hydrous saline-high-Mg carbonatitic fluid in these Archean diamonds strongly resemble those of Phanerozoic fibrous diamonds. (ubc.ca)
  • Diamonds from these two locations have been analysed for their morphology, nitrogen content and aggregation, cathodoluminescence, composition of mineral inclusions, and stable carbon isotopes. (ubc.ca)
  • In addition, fluorescence and stable nitrogen isotopes were studied in Wawa diamonds. (ubc.ca)
  • Other characteristics of the Wawa diamonds suggest a subduction-related origin, i.e. 1) the presence of peridotitic and eclogitic minerals within single diamonds in a mixed paragenesis also combining shallow and deep phases, 2) the crustal signature of nitrogen isotopes. (ubc.ca)
  • This laboratory contains air flasks waiting to be sampled, a wall lined with tanks of standards, large metal containers of liquid nitrogen, and computers showing graphs of carbon isotope ratios. (noaa.gov)
  • In peat samples corresponded to 1908 permafrost boundary they found significantly higher levels of the heavy nitrogen and carbon isotopes 15N and 13C. (spacedaily.com)
  • Using the whiskers, researchers could do a stable isotope analysis to examine carbon nitrogen ratios. (nps.gov)
  • Analysis of stable isotope ratios from mineralised tissue has been widely used for dietary reconstruction. (springer.com)
  • Mass-spectrometric stable isotope measurements of CO (sub 2) use molecular ion currents at mass-to-charge ratios m/z 44, 45 and 46 to derive the elemental isotope ratios n( (super 13) C)/n( (super 12) C) and n( (super 18) O)/n( (super 16) O), abbreviated (super 13) C/ (super 12) C and (super 18) O/ (super 16) O, relative to a reference. (eurekamag.com)
  • The magnitude of this correction depends on the calibrated isotope ratios of the reference. (eurekamag.com)
  • This reveals that only ratios of isotope ratios (namely, (super 17) R/ (super 13) R and (super 13) R (super 17) R/ (super 18) R) are required for the (super 17) O correction. (eurekamag.com)
  • Errors of similar magnitude can be introduced by the assumed mass-dependent relationship between (super 17) O/ (super 16) O and (super 18) O/ (super 16) O isotope ratios. (eurekamag.com)
  • Scientists must use math formulas to convert isotope ratios into age estimates. (icr.org)
  • Even when a radiocarbon laboratory measures very precise isotope ratios in a sample, any age estimate from the formula will only be as good as the four assumptions that went into it. (icr.org)
  • If Noah's Flood actually happened about 4,500 years ago, as the Scriptures record, then it would have affected, and possibly steamrolled, carbon-14 ratios in very old samples. (icr.org)
  • We found that, after calibration, CLM was able to reasonably simulate the observed fluxes of energy and carbon, carbon stocks, carbon isotope ratios, and ecosystem response to water stress. (copernicus.org)
  • The carbon and oxygen isotope ratios are sensitive recorders of local and regional rainfall dynamics. (pik-potsdam.de)
  • At broad spatial scales, mean N:P ratios were lowest for T. testudinum (36.5 ± 1.1) and S. filiforme (38.9 ± 1.3), and highest for H. wrightii (44.1 ± 1.8). (int-res.com)
  • Integration of metagenomic and stable carbon isotope evidence reveals the extent and mechanisms of carbon dioxide fixation in high-temperature microbial communities. (montana.edu)
  • Just a small change in the amount of iron that finds its way there can have a dramatic impact on the growth of photosynthetic organisms and their concomitant uptake of carbon dioxide. (sc.edu)
  • When algae and other phytoplankton grow, they take carbon dioxide out of the atmosphere , converting it into proteins and other carbon-based molecules that constitute living cells. (sc.edu)
  • A little iron goes a long way in allowing phytoplankton to grow and pull carbon dioxide out of the air. (sc.edu)
  • The fact that carbon dioxide is a 'greenhouse gas' - a gas that prevents a certain amount of heat radiation escaping back to space and thus maintains a generally warm climate on Earth, goes back to an idea that was first conceived, though not specifically with respect to CO2, nearly 200 years ago. (skepticalscience.com)
  • He also found that carbon dioxide was very good at trapping heat, despite being a trace gas occurring in the hundreds of parts per million (ppm) range. (skepticalscience.com)
  • The stomachs of cattle, fermentation in rice fields, fracking for natural gas, coal mines, festering bogs, burning forests - they all produce methane, the second most important greenhouse gas, after carbon dioxide. (yale.edu)
  • Spock is specifically designed for a much narrower purpose: to examine carbon (and oxygen) isotopes in atmospheric carbon dioxide. (noaa.gov)
  • Carbon dioxide comes in three different masses, depending on the isotopic makeup. (noaa.gov)
  • Spock measures these relative concentrations of the three main carbon dioxide isotopologues (molecules of the same material but with different isotopes in them) with molecular masses of 44, 45, or 46 within each air sample. (noaa.gov)
  • The isotopologues measured during stable isotope carbon dioxide mass spectrometry along with their relative abundances in the atmosphere. (noaa.gov)
  • The porous, open structure of the material gives it a great ability to adsorb the carbon dioxide. (scitechdaily.com)
  • Large investments and initiatives are underway from politicians and industry alike, to capture carbon dioxide emissions and tackle climate change. (scitechdaily.com)
  • But now, new research from Chalmers University of Technology and Stockholm University in Sweden has demonstrated the possibility of a sustainable, low-cost alternative with excellent, selective carbon dioxide-capturing properties. (scitechdaily.com)
  • In the new material, we took zeolites, which have excellent capabilities for capturing carbon dioxide, and combined them with gelatine and cellulose, which has strong mechanical properties. (scitechdaily.com)
  • Our research has shown that the cellulose does not interfere with the zeolites' ability to adsorb carbon dioxide. (scitechdaily.com)
  • Additionally, a lot of energy is required to separate the captured carbon dioxide from the amine solution for reuse. (scitechdaily.com)
  • We see our results as a very interesting piece of the puzzle in the search for a solution to the complex challenge of being able to reduce the amount of carbon dioxide in the Earth's atmosphere quickly enough to meet climate goals ," says Walter Rosas Arbelaez. (scitechdaily.com)
  • In addition to bio-based materials being more environmentally friendly, the material is a solid - once the carbon dioxide has been captured, it is therefore easier and more efficient to separate it than from the liquid amine solutions," says Professor Anders Palmqvist, research leader for the study at Chalmers. (scitechdaily.com)
  • So, when wetlands degrade, they release a lot of carbon dioxide, becoming significant sources of planet-warming greenhouse gases. (iaea.org)
  • If H pylori are present, the bacteria convert the urea into carbon dioxide, which is detected and recorded in your exhaled breath after 10 minutes. (medlineplus.gov)
  • Detailed knowledge about how climate and human activities influence the sources and sinks of greenhouse gases like carbon dioxide and methane is needed in order to make the informed and effective decisions needed for combating climate change. (lu.se)
  • Stable carbon (δ¹³C) and hydrogen (δ²H) isotopes have been used to characterize hydrocarbons for exploration, development and production since the 1960s, and have re-emerged as predictive tools with the development of unconventional "tight" oil and gas plays. (onepetro.org)
  • Stable carbon and hydrogen isotope values show a strong correlation to both initial and cumulative GOR for the unconventional Niobrara and Codell intervals of Wattenberg Field. (onepetro.org)
  • A sensitive instrument measures the ratio of carbon-14 in organic remains to the more common and stable carbon-13 and carbon-12 isotopes. (icr.org)
  • of which, the emission factors and stable carbon isotope composition are important basic data. (bvsalud.org)
  • The exhaust of each test stage was collected to analyze the carbonaceous components and stable carbon isotopes and to discuss the influencing factors. (bvsalud.org)
  • Variations in temperature, moisture and a number of other environmental properties may be recorded as changes in ring width but also, for example, as changes in the stable carbon- and oxygen-isotope composition of wood samples. (lu.se)
  • For instance, changing a hydrogen atom (H) to its isotope deuterium (D) represents a 100% increase in mass, whereas in replacing carbon-12 with carbon-13, the mass increases by only 8 percent. (wikipedia.org)
  • Maturities derived from carbon and hydrogen isotopes can serve as controls in regional maturity maps, which are used to help define areas of oil, wet gas and dry gas production. (onepetro.org)
  • Methane (CH 4 ) has one carbon atom and four hydrogen atoms. (windows2universe.org)
  • Methane is the simplest hydrocarbon, consisting of one carbon atom and four hydrogen atoms. (windows2universe.org)
  • For example, in 1989 the Sun erupted in a powerful series of flares as well as a huge coronal mass ejection (or CME), where billions of tons of hydrogen plasma is ejected at high speed. (syfy.com)
  • Carbon and oxygen isotopes of cool-water bryozoans from the Great Australian Bight and their paleoenvironmental significance. (tamu.edu)
  • Elements exist in different variations - isotopes - and it is the proportion of oxygen isotopes in the foram shells that, for example, reveals changes in global temperature and in global ice volume. (lu.se)
  • The proportion of oxygen isotopes in the shells reveals changes in global temperature and in global ice volume. (lu.se)
  • The IAEA will draw up best practice guidelines on the use of stable and radioactive isotopes to evaluate groundwater resource sustainability without damaging wetlands ( see the Science box ). (iaea.org)
  • The world leader in stable (non-radioactive) isotopes is xenon (used in photographer's high power flash lamps) with nine. (lesker.com)
  • Alpha particle ( ionizing radiation ) - two neutrons and two protons bound as a single particle (a helium nucleus) that is emitted from the nucleus of certain radioactive isotopes in the process of disintegration. (cdc.gov)
  • Beta particle ( ionizing radiation ) - a charged particle emitted from the nucleus of certain unstable atomic nuclei (radioactive isotopes), having the charge and mass of an electron. (cdc.gov)
  • For highest accuracy in the (super 13) C/ (super 12) C ratio, independent triple oxygen isotope measurements are required. (eurekamag.com)
  • It begins with isotope ratio measurements. (icr.org)
  • Despite his advanced age, Spock is still sharp, and he produces excellent high quality measurements, with a little bit of tweaking and cleaning once in a while. (noaa.gov)
  • This study combines measurements of dissolved inorganic carbon (DIC), total alkalinity (TA), pH, earth observation (EO), and ocean model products with deep learning to provide a good step forward in detecting changes in the ocean carbonate system parameters at a high spatial and temporal resolution in the North Atlantic region (Long. (mdpi.com)
  • Using various methods to characterize the 1956 storm, including measurements in visible light, radio waves, changes to the Earth's ionosphere (a high-altitude layer of ionized air that, when it changes rapidly, can affect magnetometers on the ground that measure magnetic field strength), and more, they found the 774 AD event was a staggering 30 to 70 times stronger. (syfy.com)
  • Numerous studies are under way to identify specific imaging markers for different types of dementia, including cerebral volumetric measurements, diffusion imaging, spectroscopy, very-high-field MRI scans of senile plaques, and PET scan markers of senile plaques. (medscape.com)
  • Validation of the correlation between Niobrara and Codell production GOR and stable isotope composition was provided by an independent geochemistry dataset from the USGS. (onepetro.org)
  • Foram species composition and the number of individuals tell us that there have been periods with high and low levels of nutrients in the water, that is, with strong and with weak upwelling. (lu.se)
  • The extent and mechanisms of CO2 fixation were evaluated across a comprehensive set of high-temperature, chemotrophic microbial communities in Yellowstone National Park by combining metagenomic and stable 13C isotope analyses. (montana.edu)
  • Figure S1: Stratigraphic log with the positions of the samples collected for isotope and palynological analyses at the Dacao "A," Dacao "B," and Liangshuijing sections. (figshare.com)
  • The proposed work utilises isotope analyses of deeply formed melt inclusions, tiny pockets of melt trapped in minerals, to directly determine what comes back up in subduction zones. (europa.eu)
  • Undertaking a multiple isotope study of these inclusions is now possible, owing to my recent success in significantly improving mass spectrometer detector amplifier technology that led to an order of magnitude improvement in precision for isotope analyses of small samples. (europa.eu)
  • This is all backed up by chemical analyses, including organic carbon isotope analysis clearly pointing to biomass," he said. (livescience.com)
  • Wiederhold, J. G. Metal stable isotope signatures as tracers in environmental geochemistry. (nature.com)
  • ABSTRACT: The elemental (C, N, and P) and isotope (δ 13 C, δ 15 N) content of leaves of the seagrasses Thalassia testudinum , Halodule wrightii , and Syringodium filiforme were measured across a 10000 km 2 survey of the seagrass communities of South Florida, USA, in 1999 and 2000. (int-res.com)
  • By observing Mars through a long, narrow slit, the team built up a high-resolution map of methane as the planet rotated. (newscientist.com)
  • Permafrost and glaciers in the high Arctic form an impermeable 'cryospheric cap' that traps a large reservoir of subsurface methane, preventing it from reaching the atmosphere. (nature.com)
  • At sufficiently high pressures and low temperatures, the methane beneath permafrost and glaciers can be trapped as a solid gas hydrate 6 . (nature.com)
  • This study presents evidence that these seepage pathways induce widespread groundwater-driven methane escape from glacial forefields in the Eurasian High Arctic, a region known for its vast subpermafrost gas reserves 1 . (nature.com)
  • Methane molecules from each of these sources have a characteristic ratio of two carbon isotopes, carbon-12 and carbon-13. (yale.edu)
  • Microbes fractionate the isotopes, increasing the proportion of carbon-12 compared to fossil methane. (yale.edu)
  • Yet methane from burning trees or crop residues has a higher proportion of carbon-13, because photosynthesis favors that isotope. (yale.edu)
  • Carbon isotope stratigraphy of the St. Clair from an outcrop near Dongola Hollow and from the Schlamer #1 core, both located in Alexander County, Illinois, reveals the presence of the Ireviken (early Sheinwoodian) and Mulde (middle to upper Homerian) carbon isotope excursions. (confex.com)
  • Carbon atoms have six protons but can have six, seven, or eight neutrons creating different isotopes. (lesker.com)
  • Iron is an essential element in all living creatures, and its availability in seawater can have a profound effect on phytoplankton growth and, consequently, the Earth's carbon cycle. (sc.edu)
  • The ratio of the stable natural isotopes iron-56 and iron-54 from these sources can differ from the ratio in the Earth's crust because a number of chemical processes change the ratio by favoring the release of one of the two isotopes. (sc.edu)
  • 1. Carbon-14 has been decaying at basically the same rate throughout Earth's history. (icr.org)
  • Graphite traces in a zircon dating to 4.1 billion years ago hint that at least one important component of life - carbon - was already in place within just a few million years after Earth's formation. (livescience.com)
  • The common factor in all these elements is that they are created when extremely high-energy subatomic particles hit Earth's air and ground. (syfy.com)
  • For many phototrophic communities, cyanobacteria are the primary producers, capturing solar energy and providing fixed carbon and molecular oxygen to heterotrophic populations. (frontiersin.org)
  • The emission factors of organic carbon (OC) of gasoline and natural gas vehicles were much higher than those of elemental carbon (EC) in every test stage. (bvsalud.org)
  • With increased drought, structural changes (decreased density and increased thickness) in resprouts contributed to the observed higher photosynthesis and increased g mes . (afs-journal.org)
  • During resprouting after disturbances, greater capacity to withstand drought, as evidenced by higher g mes , g s and lower non-stomatal limitants, enables increased photosynthesis and rapid growth. (afs-journal.org)
  • Spock is a highly precise isotope ratio mass spectrometer , which uses a magnetic field to separate and measure molecules of different masses (a measure of how much matter is in an object) by bending ions of different charges at different radii. (noaa.gov)
  • 13C by isotope ratio mass spectrometry. (cdc.gov)
  • The rate of a reaction involving a C-H bond is typically 6-10 times faster than the corresponding C-D bond, whereas a 12C reaction is only 4 percent faster than the corresponding 13C reaction: 445 (even though, in both cases, the isotope is one atomic mass unit heavier). (wikipedia.org)
  • Here we show the unambiguous isotopic imaging of 12 C carbon atoms embedded in 13 C graphene and the monitoring of their self-diffusion via atomic-level vibrational spectroscopy. (nature.com)
  • Lead has the highest atomic number of any stable element and concludes three major decay chains of heavier elements. (wikiversity.org)
  • On the other hand, placing the Flood back into world history reveals a bad assumption beneath higher carbon ages. (icr.org)
  • Heavier isotopes will (classically) lead to lower vibration frequencies, or, viewed quantum mechanically, will have lower zero-point energy. (wikipedia.org)
  • At the same time, the likelihood that bioherms are preserved from long-term erosion is higher when deposited during low sea level in deeper parts of the basin. (lu.se)
  • The spatial resolutions of even the most sensitive isotope analysis techniques based on light or ion probes are limited to a few hundred nanometres. (nature.com)
  • Isotope analysis in the transmission electron microscope. (nature.com)
  • Stable isotope analysis can be executed pre-completion on samples obtained from mud gas and/or gas desorbing from cuttings and core. (onepetro.org)
  • The procedure involves enzymatic hydrolysis of urine, extraction, derivatization and analysis using capillary gas chromatog-raphy combined with high resolution mass spectrometry (GC-HRMS). (cdc.gov)
  • 2) carbon and oxygen isotope analysis of CO2 from melt inclusions using a newly developed crushing technique. (europa.eu)
  • The combined first and second ionization energies -the total energy required to remove the two 6p electrons-is close to that of tin , lead's upper neighbor in the carbon group . (wikiversity.org)
  • Beta particles are high-energy electrons that are emitted from the nuclei of unstable atoms (eg, cesium-137, iodine-131). (msdmanuals.com)
  • Knowing how iron moves into the oceans is thus crucial for scientists to fully understand the details of the carbon cycle on Earth. (sc.edu)
  • Many reporters and scientists treat carbon dates like facts. (icr.org)
  • This enables scientists to better track carbon cycle responses to environmental change and tune biochemical processes in vegetation models for an improved simulation of future change. (copernicus.org)
  • Lately though, NOAA scientists are collecting a lot more samples (over 7,000 a year), all of which are measured for stable isotopes, so Spock has a lot of trouble keeping up with the demand. (noaa.gov)
  • Scientists found that the level of carbon-14, an isotope of carbon, was much higher in rings from that year than usual. (syfy.com)
  • The scientists think the 774 flare may have been a special circumstance, where a powerful flare occurred near a streamer of gas called a filament , slamming it and accelerating the protons in it to such high energies. (syfy.com)
  • Additionally, the human samples have higher stable isotope differences, in comparison with faunal samples, than would be expected within the food web, particularly for δ 13 C. This human bone collagen δ 13 C enrichment may reflect a diet rich in aquatic protein intake, which is also supported by δ 34 S archived in human and faunal samples, and the presence of oysters and cockles shells at the excavation. (springer.com)
  • The predicted contribution of different carbon sources to the consumer biomass changed between models as a function of source variability. (scielo.br)
  • The shells are made of calcium carbonate, which means that they mainly consist of the elements calcium, carbon and oxygen. (lu.se)
  • So far, the materials and processes involved have been associated with significant negative side effects and high costs. (scitechdaily.com)
  • How do possible increased extreme events such as devastating storms and flooding affect carbon cycle processes and do we already see such perturbations? (lu.se)
  • Background radioactivity - radioactive elements in the natural environment including those in the crust of the earth (like radioactive potassium, uranium, and thorium isotopes) and those produced by cosmic rays. (cdc.gov)
  • 13 Ccarb excursion and that peak values of the Hangenberg excursion in Missouri are not coincident with and cannot be accounted for by high Corg burial in epeiric seas. (usgs.gov)
  • The time equivalence between initial reef growth and the Guttenberg isotope carbon excursion (GICE) suggests that global climatic conditions were important. (lu.se)
  • Katzenberg and Weber ( 1999 ) observed a range of − 14.2 to − 24.6‰ in fish bones in Siberia with higher δ 13 C in species inhabiting shallow waters and lower δ 13 C for fish inhabiting deeper open waters on the lake. (springer.com)
  • This study investigates natural variation in C and N stable isotopes among plant species in two western Amazon flooded forests with contrasting watershed biogeochemistry (white-water várzea-forest and black-water igapó-forest). (scielo.br)
  • The elemental and stable isotope contents of all species were variable and demonstrated marked interspecific variation. (int-res.com)
  • This work documents interspecific variation in the nutrient dynamics of 3 common seagrasses in South Florida, indicating that interpretation of elemental and stable isotope values needs to be species specific. (int-res.com)
  • What surprised us most was that it was possible to fill the foam with such a high proportion of zeolites. (scitechdaily.com)
  • The proportion of carbon isotopes in the shells tells us about changes in ocean circulation, but also of local changes in upwelling areas. (lu.se)
  • Even much older material can be dated with very high precision through combination with radiocarbon dating . (lu.se)
  • Global recycling flux estimates, including carbon, are contradictory highlighting the need for a new, more precise approach to their quantification. (europa.eu)
  • I also rephrase the calculation scheme for the (super 17) O correction completely in terms of relative isotope ratio differences (delta values). (eurekamag.com)
  • The high floristic diversity of both forests was reflected in large within-site interspecific variation in both δ 13 C and δ 15 N. Paired comparisons revealed that δ 13 C of wood and fruits and δ 15 N of fruits were generally greater than values obtained for leaves from the same plant. (scielo.br)
  • A significant contribution of g mes to leaf carbon isotope discrimination values was observed. (afs-journal.org)
  • They've been collecting ocean samples and developing their analytical techniques for quantifying different natural isotopes of iron in seawater, which is one means of tracking the origins of the dissolved metal. (sc.edu)
  • John and postdoctoral associate Tim Conway have developed a high-throughput means of purifying seawater samples and determining the iron-56/iron-54 ratio, a method capable of handling the nearly 600 samples they collected in a high-resolution transect of the north Atlantic Ocean on a GEOTRACES cruise. (sc.edu)
  • A mix of high-energy light and hugely accelerated subatomic particles, when this wave impacted Earth it changed our atmospheric chemistry enough to be measured centuries later. (syfy.com)
  • Bone collagen δ 15 N can also be used to analyse access to freshwater resources, as organisms in these ecosystems exhibit higher δ 15 N than those in terrestrial ecosystems (van Klinken et al. (springer.com)
  • Intake required to meet energy requirements of an average free-ranging adult female polar bear was 2.1 kg/day on diets consumed during years with high survival but rose to 3.0 kg/day when survival was low. (usgs.gov)
  • Although bears that summered onshore in the Alaskan Beaufort Sea had higher fat diets than bears that summered on the pack ice, access to the remains of subsistence-harvested bowhead whales (Balaena mysticetus) contributed little to improving diet energy density. (usgs.gov)
  • Iain Douglas-Hamilton wrote "Dr Thure Cerling has introduced a high tech means of analyzing animal diets from carbon isotopes, and has trained Kenya staff in this technique. (savetheelephants.org)
  • I propose to better quantify global recycling fluxes by a geochemical study of two types of subduction zones: continental and oceanic zones of which the former has higher volatile fluxes and plays a key role in past and present-day climate change. (europa.eu)
  • Isotopes in Environmental and Health Studies , 36 (4), 393-396. (princeton.edu)
  • By using environmental isotopes to understand how the wetland system is sustained, we can improve water management practices and conserve wetlands, Ortega said. (iaea.org)
  • Wetlands provide homes to animals and plants and play a crucial role in climate change mitigation and adaptation by absorbing carbon and providing natural protection against storms and flooding. (iaea.org)
  • The research team studied variations in stable isotope signatures from a stalagmite that was collected in a cave near Uxbenka/Belize, an important archaeological site in the former heartland of the Maya. (pik-potsdam.de)
  • The objective of our pilot study was to determine whether ultrafine elemental carbon particles translocate to the liver and other extrapulmonary organs following inhalation as singlet particles by rats. (cdc.gov)
  • We established an efficient approach, crosslinking of segmentally isotope-labeled RNA and tandem mass spectrometry (CLIR-MS/MS), to localize protein-RNA interactions simultaneously at amino acid and nucleotide resolution. (nih.gov)
  • The religious diet restrictions might have led to a higher intake of aquatic protein when meat consumption was not allowed. (springer.com)
  • The carbon 13 urea breath test (UBT) is based on the detection of the products created when urea is split by the organism. (medscape.com)
  • Patients are asked to drink urea (usually with a beverage) labeled with a carbon isotope (carbon 13 or carbon 14). (medscape.com)
  • The only way to get particles at energies like this is from space, where powerful magnetic fields in exploding stars, for example, can accelerate the particles to such high speeds. (syfy.com)
  • But eight neutrons is too much of a good thing and carbon 14 (so called because protons + neutrons = 14) is radioactive and the nucleus breaks down to form another element. (lesker.com)
  • Kinetic isotope effects at the α-carbon can be used to develop some understanding into the symmetry of the transition state in SN2 reactions, although this kinetic isotope effect is less sensitive than what would be ideal, also due to contribution from non-vibrational factors. (wikipedia.org)
  • There is also a 17 O isotope, which is much much rarer than 13 C or 18 O. Although 12 C 17 O 16 O looks like 13 C 16 O 16 O, a small correction is made for the contribution of this isotopologue. (noaa.gov)
  • Le but de cette étude était de déterminer, chez cette espèce, la contribution des limitations de la photosynthèse, en particulier de la conductance du mésophylle ( g mes ) au cours de la repousse et sous sécheresse estivale. (afs-journal.org)
  • Forams like Uvigerina peregrina thrived during a period with a high contribution of fluvial sediment input. (lu.se)
  • The isotope data indicate that the Ireviken and Mulde are stratigraphically adjacent, suggesting that the middle Wenlock is extremely condensed or missing in these sections. (confex.com)
  • Richards and Hedges 1999 ), especially when combined with carbon isotope data. (springer.com)
  • Researchers are collecting these data to better understand what resources coyotes are using across the landscape, in areas with high to low levels of urbanization, and to provide insight into how coyotes are persisting in some of the most urban areas of Los Angeles. (nps.gov)
  • These can be, and have been, measured on conventional stable isotope mass spectrometers. (eurekamag.com)
  • Additionally, CO 2 containing an 18 O instead of 16 O oxygen isotope has mass 46. (noaa.gov)
  • Today, mass tables use the most abundant carbon isotope atom C = 12.000000 daltons (as they are called in SI units) and relate everything to one twelfth of that mass. (lesker.com)