Stable oxygen atoms that have the same atomic number as the element oxygen, but differ in atomic weight. O-17 and 18 are stable oxygen isotopes.
Creation and development of bodies within solar systems, includes study of early planetary geology.
Any solid objects moving in interplanetary space that are smaller than a planet or asteroid but larger than a molecule. Meteorites are any meteoroid that has fallen to a planetary surface. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.
A plant genus of the family MELIACEAE. Members contain cedrelanolide.
El Nino-Southern Oscillation or ENSO is a cycle of extreme alternating warm El Niño and cold La Nina events which is the dominant year-to-year climate pattern on Earth. Both terms refer to large-scale changes in sea-surface temperature across the eastern tropical Pacific. ENSO is associated with a heightened risk of certain vector-borne diseases. (From http://www.elnino.noaa.gov/lanina_new_faq.html, accessed 5/12/2020)
The group of celestial bodies, including the EARTH, orbiting around and gravitationally bound by the sun. It includes eight planets, one minor planet, and 34 natural satellites, more than 1,000 observed comets, and thousands of lesser bodies known as MINOR PLANETS (asteroids) and METEOROIDS. (From Academic American Encyclopedia, 1983)
Atomic species differing in mass number but having the same atomic number. (Grant & Hackh's Chemical Dictionary, 5th ed)
Small solar system planetary bodies including asteroids. Most asteroids are found within the gap lying between the orbits of Mars and Jupiter.
A plant genus in the family PINACEAE, order Pinales, class Pinopsida, division Coniferophyta.
Techniques for labeling a substance with a stable or radioactive isotope. It is not used for articles involving labeled substances unless the methods of labeling are substantively discussed. Tracers that may be labeled include chemical substances, cells, or microorganisms.
Stable carbon atoms that have the same atomic number as the element carbon, but differ in atomic weight. C-13 is a stable carbon isotope.
The gaseous envelope surrounding a planet or similar body. (From Random House Unabridged Dictionary, 2d ed)
Remains, impressions, or traces of animals or plants of past geological times which have been preserved in the earth's crust.
The longterm manifestations of WEATHER. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Stable nitrogen atoms that have the same atomic number as the element nitrogen, but differ in atomic weight. N-15 is a stable nitrogen isotope.
The dimension of the physical universe which, at a given place, orders the sequence of events. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
A mass of organic or inorganic solid fragmented material, or the solid fragment itself, that comes from the weathering of rock and is carried by, suspended in, or dropped by air, water, or ice. It refers also to a mass that is accumulated by any other natural agent and that forms in layers on the earth's surface, such as sand, gravel, silt, mud, fill, or loess. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1689)
The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)
Molecules or ions formed by the incomplete one-electron reduction of oxygen. These reactive oxygen intermediates include SINGLET OXYGEN; SUPEROXIDES; PEROXIDES; HYDROXYL RADICAL; and HYPOCHLOROUS ACID. They contribute to the microbicidal activity of PHAGOCYTES, regulation of signal transduction and gene expression, and the oxidative damage to NUCLEIC ACIDS; PROTEINS; and LIPIDS.
A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A functional system which includes the organisms of a natural community together with their environment. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
Stable zinc atoms that have the same atomic number as the element zinc, but differ in atomic weight. Zn-66-68, and 70 are stable zinc isotopes.
Stable sulfur atoms that have the same atomic number as the element sulfur, but differ in atomic weight. S-33, 34, and 36 are stable sulfur isotopes.

A functional model for O-O bond formation by the O2-evolving complex in photosystem II. (1/649)

The formation of molecular oxygen from water in photosynthesis is catalyzed by photosystem II at an active site containing four manganese ions that are arranged in di-mu-oxo dimanganese units (where mu is a bridging mode). The complex [H2O(terpy)Mn(O)2Mn(terpy)OH2](NO3)3 (terpy is 2,2':6', 2"-terpyridine), which was synthesized and structurally characterized, contains a di-mu-oxo manganese dimer and catalyzes the conversion of sodium hypochlorite to molecular oxygen. Oxygen-18 isotope labeling showed that water is the source of the oxygen atoms in the molecular oxygen evolved, and so this system is a functional model for photosynthetic water oxidation.  (+info)

Towards the reaction mechanism of pyrogallol-phloroglucinol transhydroxylase of Pelobacter acidigallici. (2/649)

Conversion of pyrogallol to phloroglucinol was studied with the molybdenum enzyme transhydroxylase of the strictly anaerobic fermenting bacterium Pelobacter acidigallici. Transhydroxylation experiments in H218O revealed that none of the hydroxyl groups of phloroglucinol was derived from water, confirming the concept that this enzyme transfers a hydroxyl group from the cosubstrate 1,2,3, 5-tetrahydroxybenzene (tetrahydroxybenzene) to the acceptor pyrogallol, and simultaneously regenerates the cosubstrate. This concept requires a reaction which synthesizes the cofactor de novo to maintain a sufficiently high intracellular pool during growth. Some sulfoxides and aromatic N-oxides were found to act as hydroxyl donors to convert pyrogallol to tetrahydroxybenzene. Again, water was not the source of the added hydroxyl groups; the oxides reacted as cosubstrates in a transhydroxylation reaction rather than as true oxidants in a net hydroxylation reaction. No oxidizing agent was found that supported a formation of tetrahydroxybenzene via a net hydroxylation of pyrogallol. However, conversion of pyrogallol to phloroglucinol in the absence of tetrahydroxybenzene was achieved if little pyrogallol and a high amount of enzyme preparation was used which had been pre-exposed to air. Obviously, the enzyme was oxidized by air to form sufficient amounts of tetrahydroxybenzene from pyrogallol to start the reaction. A reaction mechanism is proposed which combines an oxidative hydroxylation with a reductive dehydroxylation via the molybdenum cofactor, and allows the transfer of a hydroxyl group between tetrahydroxybenzene and pyrogallol without involvement of water. With this, the transhydroxylase differs basically from all other hydroxylating molybdenum enzymes which all use water as hydroxyl source.  (+info)

Metabolism of (R)-(+)-pulegone and (R)-(+)-menthofuran by human liver cytochrome P-450s: evidence for formation of a furan epoxide. (3/649)

(R)-(+)-Pulegone, a monoterpene constituent of pennyroyal oil, is a hepatotoxin that has been used in folklore medicine as an abortifacient despite its potential lethal effects. Pulegone is metabolized by human liver cytochrome P-450s to menthofuran, a proximate hepatotoxic metabolite of pulegone. Expressed human liver cytochrome (CYP) P-450s (1A2, 2A6, 2C9, 2C19, 2D6, 2E1, and 3A4) were tested for their ability to catalyze the oxidations of pulegone and menthofuran. Expressed CYP2E1, CYP1A2, and CYP2C19 oxidized pulegone to menthofuran, with respective Km and Vmax values of 29 microM and 8.4 nmol/min/nmol P-450 for CYP2E1, 94 microM and 2.4 nmol/min/nmol P-450 for CYP1A2, and 31 microM and 1.5 nmol/min/nmol P-450 for CYP2C19. The human liver P-450s involved in the metabolism of menthofuran are the same as pulegone except for the addition of CYP2A6. These P-450s were found to oxidize menthofuran to a newly identified metabolite, 2-hydroxymenthofuran, which is an intermediate in the formation of the known metabolites mintlactone and isomintlactone. Based on studies with 18O2 and H218O, 2-hydroxymenthofuran arises predominantly from a dihydrodiol formed from a furan epoxide. CYP2E1, CYP1A2, and CYP2C19 oxidized menthofuran with respective Km and Vmax values of 33 microM and 0.43 nmol/min/nmol P-450 for CYP2E1, 57 microM and 0.29 nmol/min/nmol P-450 for CYP1A2, and 62 microM and 0.26 nmol/min/nmol P-450 for CYP2C19.  (+info)

Origin of graphitic carbon and pentlandite in matrix olivines in the Allende meteorite. (4/649)

Matrix olivines in the Allende carbonaceous chondrite are believed to have formed by condensation processes in the primitive solar nebula. However, transmission electron microscope observations of numerous matrix olivines show that they contain abundant, previously unrecognized, nanometer-sized inclusions of pentlandite and poorly graphitized carbon. Neither of these phases would have been stable at the high-temperature conditions required to condense iron-rich olivine in the solar nebula. The presence of these inclusions is consistent with formation of the olivines by parent body processes that involved overgrowth of fine-grained organic materials and sulfides in the precursor matrix materials.  (+info)

Butanol is superior to water for performing positron emission tomography activation studies. (5/649)

[15(O)]Butanol has been shown to be superior to [15(O)]water for measuring cerebral blood flow with positron emission tomography. This work demonstrates that it is also superior for performing activation studies. Data were collected under three conditions: a visual confrontation animal-naming task, nonsense figure size discrimination, and a nonvisual darkroom control task. Time-activity curves (TAC) were obtained for regions known to be activated by the confrontation naming task to compare absolute uptake and the different kinetics of the two tracers. Also, t statistic maps were calculated from the data of 10 subjects for both tracers and compared for magnitude of change and size of activated regions. Peak uptake in the whole-brain TAC were similar for the two tracers. For all regions and conditions, the washout rate of [15(O)]butanol was 41% greater than that of [15(O)]water. At a threshold of 0, the [15(O)]water and [15(O)]butanol percent difference (nonnormalized) and t statistic (global normalization) images are nearly identical, indicating that the same property is being measured with both tracers. The [15(O)]butanol parametric images displayed at a threshold of /t/ = 5 look similar to the [15(O)]water parametric maps displayed at a threshold of /t/ = 4, which is consistent with the observation that t statistic values in [15(O)]butanol images are generally greater. The t statistic values were equal when the [15(O)]butanol parametric map was created from any subset of 6 subjects and the [15(O)]water parametric map was created from all 10 subjects. Fewer subjects need to be studied with [15(O)]butanol to reach the same statistical power as an [15(O)]water-based study.  (+info)

Isotope dilution spaces of mice injected simultaneously with deuterium, tritium and oxygen-18. (6/649)

The isotope dilution technique for measuring total body water (TBW), and the doubly labelled water (DLW) method for measuring energy expenditure, are both sensitive to small variations in the ratio of the hydrogen to oxygen-18 dilution space. Since the dilution space ratio varies between individuals, there has been much recent debate over what causes this variability (i.e. physiological differences between individuals or analytical error in the isotope determinations), and thus which values (individual or a population mean dilution space ratio) should be employed for TBW and DLW calculations. To distinguish between physiological and analytical variability, we injected 15 non-reproductive and 12 lactating mice (Mus musculus, outbred MF1) simultaneously with deuterium, tritium and oxygen-18. The two hydrogen labels were administered and analysed independently, therefore we expected a strong correlation between dilution space ratios based on deuterium and tritium if most of the variation in dilution spaces was physiological, but only a weak correlation if most of the variation was analytical. Dilution spaces were significantly influenced by reproductive status. Dilution spaces expressed as a percentage of body mass averaged 15.7 % greater in lactating mice than in non-reproductive mice. In addition, the hydrogen tracer employed had a significant effect (deuterium spaces were 2.0 % larger than tritium spaces). Deuterium and tritium dilution spaces, expressed as a percentage of body mass, were highly correlated. Dilution space ratios ranged from 0.952 to 1. 146 when using deuterium, and from 0.930 to 1.103 when using tritium. Dilution space ratios based on deuterium and tritium were also highly correlated. Comparison of standard deviations of the dilution space ratio based on deuterium in vivo and in vitro indicated that only 4.5 % of the variation in the dilution space ratios observed in the mice could be accounted for by analytical variation in the deuterium and oxygen-18 analyses. Although our results include data which were outside the limits previously regarded as biologically possible, the correlations that we detected strongly suggest that variation in the observed dilution space ratio was mostly physiological rather than analytical.  (+info)

Mechanistic studies of phosphoserine phosphatase, an enzyme related to P-type ATPases. (7/649)

Phosphoserine phosphatase belongs to a new class of phosphotransferases forming an acylphosphate during catalysis and sharing three motifs with P-type ATPases and haloacid dehalogenases. The phosphorylated residue was identified as the first aspartate in the first motif (DXDXT) by mass spectrometry analysis of peptides derived from the phosphorylated enzyme treated with NaBH(4) or alkaline [(18)O]H(2)O. Incubation of native phosphoserine phosphatase with phosphoserine in [(18)O]H(2)O did not result in (18)O incorporation in residue Asp-20, indicating that the phosphoaspartate is hydrolyzed, as in P-type ATPases, by attack of the phosphorus atom. Mutagenesis studies bearing on conserved residues indicated that four conservative changes either did not affect (S109T) or caused a moderate decrease in activity (G178A, D179E, and D183E). Other mutations inactivated the enzyme by >80% (S109A and G180A) or even by >/=99% (D179N, D183N, K158A, and K158R). Mutations G178A and D179N decreased the affinity for phosphoserine, suggesting that these residues participate in the binding of the substrate. Mutations of Asp-179 decreased the affinity for Mg(2+), indicating that this residue interacts with the cation. Thus, investigated residues appear to play an important role in the reaction mechanism of phosphoserine phosphatase, as is known for equivalent residues in P-type ATPases and haloacid dehalogenases.  (+info)

Protein-water interaction studied by solvent 1H, 2H, and 17O magnetic relaxation. (8/649)

Previous studies of the magnetic field dependence of the magnetic relaxation rate of solvent protons in protein solutions have indicated that this dependence (called relaxation dispersion) is related to the rotational Brownian motion of the solute proteins. In particular, the dispersion of the longitudinal (spin-lattice) relaxation rate 1/T1 shows a monotonic decrease with increasing field, with an inflection point corresponding to a proton Larmor frequency which is inversely proportional to the orientational relaxation time of the protein. We have now compared the relaxation dispersion of solvent 1H, 2H, and 17O In aqueous solutions of lysozyme (molecular weight 14,700) and 1H and 2H in solutions of hemocyanin (molecular weight 14,7 00) and 1H and 2H in solutions of hemocyanin (molecular weight 9 x 10(6)). The main experimental observation is that the dispersion of the relaxation rates of the three solvent nuclei in lysozyme solutions, normalized to their respective rates in pure water, is essentially the same. This is also true for 1H and 2H relaxation in hemocyanin solutions. These results confirm that entire solvent water molecules, rather than exchanging protons, are involved in the interaction. We have been unable to deduce the correct mechanism to explain the data, but we can eliminate several interaction mechanisms from consideration. For example, all observations combined cannot be explained by a simple two-site model of exchange, in which water molecules are either in sites on the protein with a relaxation rate characteristic of these sites, or else in the bulk solvent (the observed relaxation rate being the weighted average of the two). Also eliminated is the class of models in which the protein molecules induce a preferential partial alignment of neighboring solvent molecules, for example by electrostatic interaction of the electric dipole moments of the water with the electric fields produced by surface charges of the protein molecules. In addition, the idea that relaxation of solvent nuclei is due, in the main, to interactions with protein protons is precluded. Rather, it appears that the protein molecules influence the dynamics of the motion of solvent water molecules in their neighborhood in a manner that imposes on all the solvent molecules a correlation time for their orientational relaxation which equals that of the solute proteins.  (+info)

Oxygen isotopes are different forms or varieties of the element oxygen that have the same number of protons in their atomic nuclei, which is 8, but a different number of neutrons. The most common oxygen isotopes are oxygen-16 (^{16}O), which contains 8 protons and 8 neutrons, and oxygen-18 (^{18}O), which contains 8 protons and 10 neutrons.

The ratio of these oxygen isotopes can vary in different substances, such as water molecules, and can provide valuable information about the origins and history of those substances. For example, scientists can use the ratio of oxygen-18 to oxygen-16 in ancient ice cores or fossilized bones to learn about past climate conditions or the diets of ancient organisms.

In medical contexts, oxygen isotopes may be used in diagnostic tests or treatments, such as positron emission tomography (PET) scans, where a radioactive isotope of oxygen (such as oxygen-15) is introduced into the body and emits positrons that can be detected by specialized equipment to create detailed images of internal structures.

Planetary evolution is a field of study that focuses on the processes that have shaped the formation, development, and changes of planets and other celestial bodies over time. This encompasses various scientific disciplines, including astronomy, astrobiology, geology, and atmospheric science. The study of planetary evolution helps scientists understand how planets form, how they change over time, and the conditions that allow for the development of life.

The process of planetary evolution can be driven by a variety of factors, including:

1. Formation: Planets form from a protoplanetary disk, a rotating disk of gas and dust surrounding a young star. Over time, solid particles in the disk collide and stick together to form larger and larger bodies, eventually leading to the formation of planets.
2. Internal differentiation: As planets grow, their interiors differentiate into layers based on density, with heavier materials sinking towards the center and lighter materials rising towards the surface. This process can lead to the formation of a core, mantle, and crust.
3. Geological activity: Planetary evolution is also influenced by geological processes such as volcanism, tectonics, and erosion. These processes can shape the planet's surface, create mountain ranges, and carve out valleys and basins.
4. Atmospheric evolution: The evolution of a planet's atmosphere is closely tied to its geological activity and the presence of volatiles (gases that easily vaporize). Over time, the composition of a planet's atmosphere can change due to processes such as outgassing from the interior, chemical reactions, and interactions with the solar wind.
5. Climate evolution: The climate of a planet can also evolve over time due to changes in its orbit, axial tilt, and atmospheric composition. These factors can influence the amount of sunlight a planet receives and the greenhouse effect, which can lead to global warming or cooling.
6. Impact events: Collisions with other celestial bodies, such as asteroids and comets, can significantly impact a planet's evolution by causing large-scale changes to its surface and atmosphere.
7. Life: On planets where life emerges, biological processes can also play a role in shaping the planet's environment and influencing its evolution. For example, photosynthetic organisms can produce oxygen, which can alter the composition of a planet's atmosphere.

Understanding the various factors that contribute to a planet's evolution is crucial for understanding the formation and development of planetary systems and searching for potentially habitable exoplanets.

I'm sorry for any confusion, but "meteoroids" is not a term used in medical definitions. It is a term from the field of astronomy. Meteoroids are small particles or bits of rock that are traveling in space. When they enter the Earth's atmosphere, they can become meteors (also known as "shooting stars") and can sometimes make it to the ground as meteorites.

Oxygen is a colorless, odorless, tasteless gas that constitutes about 21% of the earth's atmosphere. It is a crucial element for human and most living organisms as it is vital for respiration. Inhaled oxygen enters the lungs and binds to hemoglobin in red blood cells, which carries it to tissues throughout the body where it is used to convert nutrients into energy and carbon dioxide, a waste product that is exhaled.

Medically, supplemental oxygen therapy may be provided to patients with conditions such as chronic obstructive pulmonary disease (COPD), pneumonia, heart failure, or other medical conditions that impair the body's ability to extract sufficient oxygen from the air. Oxygen can be administered through various devices, including nasal cannulas, face masks, and ventilators.

I apologize for any confusion, but "Cedrela" is not a medical term or concept. It is the name of a genus of trees that are commonly known as cedars. The wood from these trees is often used in various industries, including furniture making and construction. I hope this clarifies things for you. If you have any questions related to medicine or health, please don't hesitate to ask!

The El Niño-Southern Oscillation (ENSO) is a natural climate phenomenon that occurs in the Pacific Ocean. It is a periodic fluctuation in sea surface temperature and air pressure of the overlying atmosphere across the equatorial Pacific Ocean. ENSO has two main phases: El Niño and La Niña.

El Niño phase: During an El Niño event, the surface waters in the central and eastern tropical Pacific Ocean become warmer than average, and the atmospheric pressure in the western Pacific decreases relative to the eastern Pacific. This leads to a weakening or even reversal of the Walker circulation, which typically brings cooler water from the deep ocean to the surface in the eastern Pacific. El Niño can cause significant changes in weather patterns around the world, often leading to droughts in some regions and heavy rainfall and flooding in others.

La Niña phase: During a La Niña event, the surface waters in the central and eastern tropical Pacific Ocean become cooler than average, and the atmospheric pressure in the western Pacific increases relative to the eastern Pacific. This strengthens the Walker circulation, leading to increased upwelling of cold water in the eastern Pacific. La Niña can also cause significant changes in weather patterns around the world, often resulting in opposite effects compared to El Niño, such as increased rainfall and flooding in some regions and droughts in others.

The ENSO cycle typically lasts between 2-7 years, with an average of about 4-5 years. The fluctuations in ocean temperatures and atmospheric pressure can have substantial impacts on global climate, affecting temperature, precipitation, and storm patterns worldwide.

I'm sorry for any confusion, but "Solar System" is not a medical term. It refers to the astronomical system that includes our star, the Sun, and the objects that orbit it, such as planets, dwarf planets, asteroids, comets, and meteoroids. The Solar System is located in the Milky Way galaxy. If you have any medical terms or concepts you would like me to define or explain, I'd be happy to help!

Isotopes are variants of a chemical element that have the same number of protons in their atomic nucleus, but a different number of neutrons. This means they have different atomic masses, but share similar chemical properties. Some isotopes are stable and do not decay naturally, while others are unstable and radioactive, undergoing radioactive decay and emitting radiation in the process. These radioisotopes are often used in medical imaging and treatment procedures.

I'm sorry for any confusion, but the term "minor planets" is not typically used in medical definitions. It is a term from astronomy that refers to small celestial bodies orbiting the Sun, which are smaller than planets and dwarf planets. They are also commonly known as asteroids. If you have any questions related to medical terminology or health concerns, I would be happy to help with those instead!

"Larix" is not a medical term. It is the genus name for a group of trees commonly known as larches, which belong to the family Pinaceae. These deciduous conifers are native to the cooler temperate regions of the Northern Hemisphere. They are known for their needle-like leaves and cone-bearing fruits.

While not directly related to human health or medicine, certain compounds derived from plants in the Larix genus have been studied for potential medicinal properties. For example, extracts from larch bark have been investigated for their anti-inflammatory, antioxidant, and wound-healing effects. However, it is important to note that these studies are still in the preliminary stages, and more research is needed before any definitive conclusions can be drawn about the medicinal applications of Larix species.

Isotope labeling is a scientific technique used in the field of medicine, particularly in molecular biology, chemistry, and pharmacology. It involves replacing one or more atoms in a molecule with a radioactive or stable isotope of the same element. This modified molecule can then be traced and analyzed to study its structure, function, metabolism, or interaction with other molecules within biological systems.

Radioisotope labeling uses unstable radioactive isotopes that emit radiation, allowing for detection and quantification of the labeled molecule using various imaging techniques, such as positron emission tomography (PET) or single-photon emission computed tomography (SPECT). This approach is particularly useful in tracking the distribution and metabolism of drugs, hormones, or other biomolecules in living organisms.

Stable isotope labeling, on the other hand, employs non-radioactive isotopes that do not emit radiation. These isotopes have different atomic masses compared to their natural counterparts and can be detected using mass spectrometry. Stable isotope labeling is often used in metabolic studies, protein turnover analysis, or for identifying the origin of specific molecules within complex biological samples.

In summary, isotope labeling is a versatile tool in medical research that enables researchers to investigate various aspects of molecular behavior and interactions within biological systems.

Carbon isotopes are variants of the chemical element carbon that have different numbers of neutrons in their atomic nuclei. The most common and stable isotope of carbon is carbon-12 (^{12}C), which contains six protons and six neutrons. However, carbon can also come in other forms, known as isotopes, which contain different numbers of neutrons.

Carbon-13 (^{13}C) is a stable isotope of carbon that contains seven neutrons in its nucleus. It makes up about 1.1% of all carbon found on Earth and is used in various scientific applications, such as in tracing the metabolic pathways of organisms or in studying the age of fossilized materials.

Carbon-14 (^{14}C), also known as radiocarbon, is a radioactive isotope of carbon that contains eight neutrons in its nucleus. It is produced naturally in the atmosphere through the interaction of cosmic rays with nitrogen gas. Carbon-14 has a half-life of about 5,730 years, which makes it useful for dating organic materials, such as archaeological artifacts or fossils, up to around 60,000 years old.

Carbon isotopes are important in many scientific fields, including geology, biology, and medicine, and are used in a variety of applications, from studying the Earth's climate history to diagnosing medical conditions.

In medical terms, the term "atmosphere" is not typically used as a standalone definition or diagnosis. However, in some contexts, it may refer to the physical environment or surroundings in which medical care is provided. For example, some hospitals and healthcare facilities may have different atmospheres depending on their specialties, design, or overall ambiance.

Additionally, "atmosphere" may also be used more broadly to describe the social or emotional climate of a particular healthcare setting. For instance, a healthcare provider might describe a patient's home atmosphere as warm and welcoming, or a hospital ward's atmosphere as tense or chaotic.

It is important to note that "atmosphere" is not a medical term with a specific definition, so its meaning may vary depending on the context in which it is used.

In medical terms, "fossils" do not have a specific or direct relevance to the field. However, in a broader scientific context, fossils are the remains or impressions of prehistoric organisms preserved in petrified form or as a mold or cast in rock. They offer valuable evidence about the Earth's history and the life forms that existed on it millions of years ago.

Paleopathology is a subfield of paleontology that deals with the study of diseases in fossils, which can provide insights into the evolution of diseases and human health over time.

Climate, in the context of environmental science and medicine, refers to the long-term average of weather conditions (such as temperature, humidity, atmospheric pressure, wind, rainfall, and other meteorological elements) in a given region over a period of years to decades. It is the statistical description of the weather patterns that occur in a particular location over long periods of time.

In medical terms, climate can have significant impacts on human health, both physical and mental. For example, extreme temperatures, air pollution, and ultraviolet radiation levels associated with certain climates can increase the risk of respiratory and cardiovascular diseases, heat-related illnesses, and skin cancer. Similarly, changes in climate patterns can affect the distribution and prevalence of infectious diseases, such as malaria and Lyme disease.

Climate change, which refers to significant long-term changes in the statistical distribution of weather patterns over periods ranging from decades to millions of years, can have even more profound impacts on human health, including increased rates of heat-related illnesses and deaths, worsening air quality, and altered transmission patterns of infectious diseases.

Nitrogen isotopes are different forms of the nitrogen element (N), which have varying numbers of neutrons in their atomic nuclei. The most common nitrogen isotope is N-14, which contains 7 protons and 7 neutrons in its nucleus. However, there are also heavier stable isotopes such as N-15, which contains one extra neutron.

In medical terms, nitrogen isotopes can be used in research and diagnostic procedures to study various biological processes. For example, N-15 can be used in a technique called "nitrogen-15 nuclear magnetic resonance (NMR) spectroscopy" to investigate the metabolism of nitrogen-containing compounds in the body. Additionally, stable isotope labeling with nitrogen-15 has been used in clinical trials and research studies to track the fate of drugs and nutrients in the body.

In some cases, radioactive nitrogen isotopes such as N-13 or N-16 may also be used in medical imaging techniques like positron emission tomography (PET) scans to visualize and diagnose various diseases and conditions. However, these applications are less common than the use of stable nitrogen isotopes.

"Time" is not a medical term or concept. It is a fundamental concept in physics that refers to the ongoing sequence of events taking place. While there are medical terms that include the word "time," such as "reaction time" or "pregnancy due date," these refer to specific measurements or periods within a medical context, rather than the concept of time itself.

I'm sorry for any confusion, but "geologic sediments" is not a term used in medical definitions. Geological sediments are deposits of material that accumulate over time, usually in layers, as a result of natural geological processes such as weathering, erosion, and deposition. These sediments can eventually become rock formations and provide important clues about the Earth's history, including information about past climates, environments, and life on Earth.

Oxygen consumption, also known as oxygen uptake, is the amount of oxygen that is consumed or utilized by the body during a specific period of time, usually measured in liters per minute (L/min). It is a common measurement used in exercise physiology and critical care medicine to assess an individual's aerobic metabolism and overall health status.

In clinical settings, oxygen consumption is often measured during cardiopulmonary exercise testing (CPET) to evaluate cardiovascular function, pulmonary function, and exercise capacity in patients with various medical conditions such as heart failure, chronic obstructive pulmonary disease (COPD), and other respiratory or cardiac disorders.

During exercise, oxygen is consumed by the muscles to generate energy through a process called oxidative phosphorylation. The amount of oxygen consumed during exercise can provide important information about an individual's fitness level, exercise capacity, and overall health status. Additionally, measuring oxygen consumption can help healthcare providers assess the effectiveness of treatments and rehabilitation programs in patients with various medical conditions.

Reactive Oxygen Species (ROS) are highly reactive molecules containing oxygen, including peroxides, superoxide, hydroxyl radical, and singlet oxygen. They are naturally produced as byproducts of normal cellular metabolism in the mitochondria, and can also be generated by external sources such as ionizing radiation, tobacco smoke, and air pollutants. At low or moderate concentrations, ROS play important roles in cell signaling and homeostasis, but at high concentrations, they can cause significant damage to cell structures, including lipids, proteins, and DNA, leading to oxidative stress and potential cell death.

Medical definitions of water generally describe it as a colorless, odorless, tasteless liquid that is essential for all forms of life. It is a universal solvent, making it an excellent medium for transporting nutrients and waste products within the body. Water constitutes about 50-70% of an individual's body weight, depending on factors such as age, sex, and muscle mass.

In medical terms, water has several important functions in the human body:

1. Regulation of body temperature through perspiration and respiration.
2. Acting as a lubricant for joints and tissues.
3. Facilitating digestion by helping to break down food particles.
4. Transporting nutrients, oxygen, and waste products throughout the body.
5. Helping to maintain healthy skin and mucous membranes.
6. Assisting in the regulation of various bodily functions, such as blood pressure and heart rate.

Dehydration can occur when an individual does not consume enough water or loses too much fluid due to illness, exercise, or other factors. This can lead to a variety of symptoms, including dry mouth, fatigue, dizziness, and confusion. Severe dehydration can be life-threatening if left untreated.

An "ecosystem" is not a term that has a specific medical definition, as it is a concept that is more commonly used in the fields of ecology and environmental science. However, I can provide you with the general ecological definition of an ecosystem:

An ecosystem is a community of living organisms interacting with each other and their non-living environment, including both biotic factors (plants, animals, microorganisms) and abiotic factors (climate, soil, water, and air). These interactions create a complex network of relationships that form the foundation of ecological processes, such as energy flow, nutrient cycling, and population dynamics.

While there is no direct medical definition for an ecosystem, understanding the principles of ecosystems can have important implications for human health. For example, healthy ecosystems can provide clean air and water, regulate climate, support food production, and offer opportunities for recreation and relaxation, all of which contribute to overall well-being. Conversely, degraded ecosystems can lead to increased exposure to environmental hazards, reduced access to natural resources, and heightened risks of infectious diseases. Therefore, maintaining the health and integrity of ecosystems is crucial for promoting human health and preventing disease.

Temperature, in a medical context, is a measure of the degree of hotness or coldness of a body or environment. It is usually measured using a thermometer and reported in degrees Celsius (°C), degrees Fahrenheit (°F), or kelvin (K). In the human body, normal core temperature ranges from about 36.5-37.5°C (97.7-99.5°F) when measured rectally, and can vary slightly depending on factors such as time of day, physical activity, and menstrual cycle. Elevated body temperature is a common sign of infection or inflammation, while abnormally low body temperature can indicate hypothermia or other medical conditions.

Zinc isotopes refer to variants of the chemical element zinc, each with a different number of neutrons in their atomic nucleus. Zinc has five stable isotopes: zinc-64, zinc-66, zinc-67, zinc-68, and zinc-70. These isotopes have naturally occurring abundances that vary, with zinc-64 being the most abundant at approximately 48.6%.

Additionally, there are also several radioactive isotopes of zinc, including zinc-65, zinc-71, and zinc-72, among others. These isotopes have unstable nuclei that decay over time, emitting radiation in the process. They are not found naturally on Earth and must be produced artificially through nuclear reactions.

Medical Definition: Zinc isotopes refer to variants of the chemical element zinc with different numbers of neutrons in their atomic nucleus, including stable isotopes such as zinc-64, zinc-66, zinc-67, zinc-68, and zinc-70, and radioactive isotopes such as zinc-65, zinc-71, and zinc-72.

Sulfur isotopes are different forms of the chemical element sulfur, each with a distinct number of neutrons in their atomic nuclei. The most common sulfur isotopes are sulfur-32 (with 16 neutrons) and sulfur-34 (with 18 neutrons). These isotopes have similar chemical properties but different atomic masses, which can be used to trace the movement and cycling of sulfur through various environmental processes, such as volcanic emissions, bacterial metabolism, and fossil fuel combustion. The relative abundances of sulfur isotopes can also provide information about the origins and history of sulfur-containing minerals and compounds.

Heaviest particle-bound isotope of oxygen, see Nuclear drip line Natural oxygen is made of three stable isotopes, 16 O , 17 O ... As some methods of isotope separation enrich not only heavier isotopes of hydrogen but also heavier isotopes of oxygen when ... Isotopes of oxygen, Oxygen, Lists of isotopes by element). ... Oxygen isotopes are also used to trace ocean composition and ... Due to natural oxygen being mostly 16 O, samples enriched with the other stable isotopes can be used for isotope labeling. For ...
... s are cyclical variations in the ratio of the abundance of oxygen with an atomic mass of 18 to the ... ventilation and so on affect the accuracy of oxygen isotope measurements. Solid samples (organic and inorganic) for oxygen ... Oxygen isotope analysis considers only the ratio of 18O to 16O present in a sample. The calculated ratio of the masses of each ... Oxygen (chemical symbol O) has three naturally occurring isotopes: 16O, 17O, and 18O, where the 16, 17 and 18 refer to the ...
Oxygen isotopes and sea level. Nature 324, 137-140. C. Waelbroeck, L. Labeyrie, E. Michel, et al., (2002) Sea-level and deep ... Clumped isotopes are heavy isotopes that are bonded to other heavy isotopes. The relative abundance of clumped isotopes (and ... the study of which forms the basis of clumped isotope geochemistry. When a heavier isotope substitutes for a lighter isotope (e ... Fractionation of the stable isotopes of oxygen and carbon in carbon dioxide during the reaction of calcite with phosphoric acid ...
Valley, John W. (Jan 2003). "Oxygen Isotopes in Zircon". Reviews in Mineralogy and Geochemistry. 53 (1): 343-385. Bibcode: ... Kinny, Peter D.; Maas, Roland (Jan 2003). "Lu-Hf and Sm-Nd isotope systems in zircon". Reviews in Mineralogy and Geochemistry. ... Zircon is also useful because its incorporation of other elements like uranium, lutetium, samarium, and oxygen can be analyzed ... Slow diffusion rates also prevent contamination by leaking or loss of isotopes from the crystal, increasing the likelihood that ...
Oxygen isotope ratios in fossilized bone are sometimes used to determine the temperature at which the bone was deposited, as ... Barrick, R. E.; Stoskopf, M. K.; Showers, W. J. (1999). "Oxygen isotopes in dinosaur bones". In Farlow, J. O.; Brett-Surman, M ... Other scientists have pointed out that the ratio of oxygen isotopes in the fossils today does not necessarily represent the ... Trueman, C.; Chenery, C.; Eberth, D. A.; Spiro, B. (2003). "Diagenetic effects on the oxygen isotope composition of bones of ...
Isotopes of oxygen Dole, Malcolm (1936). "The Relative Atomic Weight of Oxygen in Water and in Air". Journal of Chemical ... The Dole effect, named after Malcolm Dole, describes an inequality in the ratio of the heavy isotope 18O (a "standard" oxygen ... 1989). "Differential fractionation of oxygen isotopes by cyanide-resistant and cyanide-sensitive respiration in plants". Planta ... Morita, N. (1935). "The increased density of air oxygen relative to water oxygen". J. Chem. Soc. Japan. 56: 1291. Kroopnick, P ...
Oxygen isotope studies had been performed before the modern era, both on Earth rocks and meteorites. However, isotope ... Although the carbon and nitrogen isotopes are closer to CI, the oxygen isotopes, which predominate, are not CI-like. Tagish ... These are the macroscopic samples with the heaviest oxygen in the Solar System. Oxygen isotope studies and classification have ... with different isotope ratios. The three stable O-isotopes are 16O, 17O, and 18O. A "three-isotope plot" (17O/16O axis versus ...
Clayton and Mayeda studied variations in the ratio of oxygen-17 and oxygen-18 to the most abundant isotope oxygen-16, building ... Clayton worked in the field of cosmochemistry and is best known for the use of the stable isotopes of oxygen to classify ... Clayton and Mayeda studied the Achondrite meteorites and showed that variations in the oxygen isotope ratios within a planet ... Clayton, Robert N.; Onuma, Naoki; Mayeda, Toshiko K. (1976-04-01). "A classification of meteorites based on oxygen isotopes". ...
They studied variations in the abundances of the stable isotopes of oxygen, oxygen-16, oxygen-17 and oxygen-18, and deduced ... From the 1970s until the late 1990s Mayeda and Clayton became famous for their use of oxygen isotopes to classify meteorites. ... They used mass spectrometry to measure oxygen isotopes in the shells of marine molluscs which gave information on the ... Mayeda and Clayton's first research paper considered the use of Bromine pentafluoride to extract Isotopes of oxygen from rocks ...
The heavy isotopes of hydrogen and oxygen in rainwater (so-called meteoric water) are enriched as a function of the ... DOI: 10.1039/CS9972600401 "Oxygen - Isotopes and Hydrology". SAHRA. Archived from the original on 2 January 2007. Retrieved 10 ... Measurements of small variations in the natural abundances of deuterium, along with those of the stable heavy oxygen isotopes ... also differentially alter the ratios of heavy hydrogen and oxygen isotopes in fresh and salt waters, in characteristic and ...
Blatt, H. (1 March 1987). "Perspectives; Oxygen isotopes and the origin of quartz". Journal of Sedimentary Research. 57 (2): ...
In the 1990s, in addition to continued work on radiocarbon calibration and solar variability, he began work on oxygen isotopes ... Stuiver, M. and P. M. Grootes (2000). "GISP2 oxygen isotope ratios." Quaternary Research 53(3): 277-283. Steven W. Leavitt ( ... There he built the Quaternary Isotope Lab with a lead-lined room 30 feet below ground to shield the hand-built gas counters ... Their sub-annual resolution stable isotopes measurements provided confirmation of the rapid nature of major climatic changes at ...
Oxygen has three stable isotopes, 16O, 17O, and 18O. Oxygen ratios are measured relative to Vienna Standard Mean Ocean Water ( ... Typically, the VPDB oxygen reference is used for paleoclimate, while VSMOW is used for most other applications. Oxygen isotopes ... USGS Tritium/Helium-3 Dating Hydrologic Isotope Tracers - Helium Cosmogenic isotopes Environmental isotopes Geochemistry ... Carbon has two stable isotopes, 12C and 13C, and one radioactive isotope, 14C. The stable carbon isotope ratio, δ13C, is ...
Species of Foraminifera incorporate oxygen as calcium carbonate in their shells. The ratio of the oxygen isotopes oxygen-16 and ... The relative abundance of such stable isotopes can be measured experimentally (isotope analysis), yielding an isotope ratio ... This field is termed stable isotope geochemistry. Measurement of the ratios of naturally occurring stable isotopes (isotope ... oxygen and sulfur) are also finding uses in ecological and biological studies. Other workers have used oxygen isotope ratios to ...
Karhu, J.A.; Holland, H.D. (1 October 1996). "Carbon isotopes and the rise of atmospheric oxygen". Geology. 24 (10): 867-870. ... Oxygen only began to persist in the atmosphere in small quantities about 50 million years before the start of the Great ... Oxygen is a reactive compound, and should eventually combine with gases and minerals of the Earth's atmosphere and crust. ... Traces of methane (at an amount of 100,000 tonnes produced per year) should not exist, as methane is combustible in an oxygen ...
"Oxygen isotopes and emerald trade routes since antiquity". Science. 287 (5453): 631-633. Bibcode:2000Sci...287..631G. doi: ...
Oxygen isotope ratio in atmosphere varies predictably with time of year and geographic location; e.g. there is a 2% difference ... Different oxygen isotopic signatures can indicate the origin of material ejected into space. The Moon's titanium isotope ratio ... The rate of exchange of surface isotopes with the environment has to be taken in account. The oxygen isotopic signatures of ... October 2001). "Oxygen Isotopes and the Moon-Forming Giant Impact". Science. 294 (12): 345-348. Bibcode:2001Sci...294..345W. ...
Various isotopes of oxygen are present on the Moon in the form of 16O, 17O, and 18O. At least twenty different possible ... Wiechert, U.; Halliday, A. N.; Lee, D.-C.; Snyder, G. A.; Taylor, L. A.; Rumble, D. (2001). "Oxygen Isotopes and the Moon- ... The elemental oxygen content in the regolith is estimated at 45% by weight. Oxygen is often found in iron-rich lunar minerals ... Oxygen from lunar regolith oxides can be a source for metabolic oxygen and rocket propellant oxidizer. Water ice can provide ...
However, this hypothesis does not adequately explain the essentially identical oxygen isotope ratios of the two bodies. This is ... Scott, Edward R. D. (December 3, 2001). "Oxygen Isotopes Give Clues to the Formation of Planets, Moons, and Asteroids". ... "Oxygen Isotopes and the Moon-Forming Giant Impact". Science. 294 (12): 345-348. Bibcode:2001Sci...294..345W. doi:10.1126/ ... The Moon's oxygen isotopic ratios seem to be essentially identical to Earth's. Oxygen isotopic ratios, which may be measured ...
October 2001). "Oxygen Isotopes and the Moon-Forming Giant Impact". Science. 294 (12): 345-348. Bibcode:2001Sci...294..345W. ... Scott, Edward R. D. (December 3, 2001). "Oxygen Isotopes Give Clues to the Formation of Planets, Moons, and Asteroids". ... The Moon's oxygen isotopic ratios are essentially identical to those of Earth. Oxygen isotopic ratios, which may be measured ... which show oxygen isotope ratios nearly identical to those of Earth. The highly anorthositic composition of the lunar crust, as ...
As oxygen isotopes (18O and 16O) and hydrogen isotopes (2H and 1H) have different masses, they behave differently in the ... describes the global annual average relationship between hydrogen and oxygen isotope (Oxygen-18 and Deuterium) ratios in ... Gat, J. R. (1996). "Oxygen and hydrogen isotopes in the hydrologic cycle". Annual Review of Earth and Planetary Sciences. 24 (1 ... The relationship of δ18O and δ2H in meteoric water is caused by mass dependent fractionation of oxygen and hydrogen isotopes ...
"Oxygen Isotopes and the Moon-Forming Giant Impact". Science. 294 (12): 345-348. Bibcode:2001Sci...294..345W. doi:10.1126/ ... A torus of oxygen and hydrogen produced by Saturn's moon, Enceladus forms part of the E ring around Saturn. Nitrogen gas ... The Io plasma torus is a transfer of oxygen and sulfur from the tenuous atmosphere of Jupiter's volcanic moon, Io and other ... In the case of the latter, however, virtually identical isotope ratios found in samples of the Earth and Moon cannot be ...
Gat, J. R. (May 1996). "Oxygen and Hydrogen Isotopes in the Hydrologic Cycle". Annual Review of Earth and Planetary Sciences. ... Jasechko, Scott (September 2019). "Global Isotope Hydrogeology―Review". Reviews of Geophysics. 57 (3): 835-965. Bibcode: ...
Evidence from Oxygen Isotopes". Science. New York City. 265 (5169): 222-224. Bibcode:1994Sci...265..222B. doi:10.1126/science. ...
64: 1315-1326, 1953). (See Oxygen isotope ratio cycle.) He retired from the university in 1972 but continued to write and run ... He worked closely with Harold Urey to find a way to use the ratio of oxygen isotopes to determine temperatures in previous eras ...
... and copper isotopes in Y-Ba-Cu-O, substituting oxygen isotopes in La-Sr-Cu-O, and substituting carbon and alkali isotopes in ... "Oxygen isotope study of YBa2Cu3O7". Physical Review B. 39 (4): 2269-2278. doi:10.1103/physrevb.39.2269. Bourne, L. C.; Zettl, A ... "Observation of an oxygen isotope shift in the superconducting transition temperature of La1.85Sr0.15CuO4". Physical Review ... doi:10.1016/S0921-4534(97)01010-1. Burk, B.; Crespi, Vincent H.; Zettl, A.; Cohen, Marvin L. (6 June 1994). "Rubidium isotope ...
2001). "Oxygen isotope ratios and rare earth elements in 3.3 to 4.4 Ga zircons: Ion microprobe evidence for high δ18O ... 2006). Oxygen isotopes, REE and U-Pb behaviour during metamorphic zircon formation. Geochimica Et Cosmochimica Acta, 70(18), ... Highly precise in situ SIMS measurements of oxygen isotopes and OH/O ratios, laser-ablation inductively-coupled mass ... Valley JW, Chiarenzelli JR, McLelland JM (1994). "Oxygen isotope geochemistry of zircon". Earth and Planetary Science Letters ...
The most widely studied and used isotopes in archaeology are carbon, oxygen, nitrogen, strontium and calcium. An isotope is an ... As with carbon, oxygen isotopic ratio variances can be attributed to specific locations and the proportion of O isotopes can ... Oxygen and nitrogen occur in the form of different isotopes which vary in their proportions geospatially and climatically. ... TIMS, ICP-MS and gas mass spectrometry have all been applied to the strontium, lead, and oxygen isotopes in Ötzi's bones and ...
Guy, R. D.; Fogel, M. L.; Berry, J. A. (1993-01-01). "Photosynthetic Fractionation of the Stable Isotopes of Oxygen and Carbon ... CS1 maint: multiple names: authors list, CS1 errors: periodical ignored, CS1 maint: others, Isotope separation, Isotopes of ... Understanding these variations in carbon fractionation across species is applied in isotope geochemistry and ecological isotope ... then releases molecular oxygen as a product. Organic carbon contains less of the stable isotope Carbon-13, or 13C, relative to ...
Shchepinov, Mikhail S (2007). "Reactive Oxygen Species, Isotope Effect, Essential Nutrients, and Enhanced Longevity". ... A heavy isotope diet is one in that contains nutrients in which some atoms are replaced with their heavier non-radioactive ... One of the most pernicious and irreparable types of oxidative damage inflicted by reactive oxygen species (ROS) upon ... Li, Xiyan; Snyder, Michael P (2016). "Yeast longevity promoted by reversing aging-associated decline in heavy isotope content ...
Mandernack KW, Bazylinski DA, Shanks WC, Bullen TD (September 1999). "Oxygen and iron isotope studies of magnetite produced by ... When isotopes diffuse, the lower mass isotopes diffuse more quickly than the heavier isotopes, resulting in fractionation. This ... Stable iron isotopes are described as the relative abundance of each of the stable isotopes with respect to 54Fe. The standard ... Diffusion of isotopes through a solution or material can also result in fractionations, as the lighter mass isotopes are able ...
Heaviest particle-bound isotope of oxygen, see Nuclear drip line Natural oxygen is made of three stable isotopes, 16 O , 17 O ... As some methods of isotope separation enrich not only heavier isotopes of hydrogen but also heavier isotopes of oxygen when ... Isotopes of oxygen, Oxygen, Lists of isotopes by element). ... Oxygen isotopes are also used to trace ocean composition and ... Due to natural oxygen being mostly 16 O, samples enriched with the other stable isotopes can be used for isotope labeling. For ...
Abstract: N71.00012 : Probing Oxygen Content and Oxygen Isotope Effect in Manganite/Cuprate Heterostructures*. 2:06 PM-2:18 PM ... and oxygen isotope effect (OIE) studies on LCMO/YBCO/LCMO trilayers grown by pulsed laser deposition. XAS is used to measure ... the YBCO oxygen content vs. layer thickness, thus determining the extent epitaxial strain deoxygenates YBCO. OIE is studied by ...
Rapid Changes in Oxygen Isotope Content of Ice Cores Caused by Fractionation and Trajectory Dispersion near the Edge of an Ice ... Oxygen isotopes in ice cores extracted from polar regions exhibit a decreasing trend in the ratio of the heavy to light ... Ice Cores, Oxygen Isotopes, "Ice Age", Sea-Floor Sediments, Greenland Ice Shelves, Precipitation Projectories, Ice Crystals, ... Download Rapid Changes in Oxygen Isotope Content of Ice Cores Caused by Fractionation and Trajectory Dispersion near the Edge ...
High resolution oxygen isotope stratigraphy of IODP sites U1394, U1395 and U1396 offshore Montserrat, Lesser Antilles (NERC ... Download Resource locator , Format: N/A, Dataset: High resolution oxygen isotope stratigraphy of IODP sites U1394, U1395 and ... Download Resource locator , Format: N/A, Dataset: High resolution oxygen isotope stratigraphy of IODP sites U1394, U1395 and ... Planktic foraminiferal oxygen and carbon stable isotope data (NERC Grant NE/P013112/1) ...
Oxygen-17 makes up an additional 0.037%, and oxygen-18, 0.200% of all oxygen atoms. A number of radioactive isotopes of the ... Oxygen. General Properties, Where Oxygen Comes From, How We Use Oxygen, Chemistry And Compounds. ... Oxygen is a non-metal in group 16 of the periodic table. Its three stable isotopes have atomic weights of 16, 17, and 18. The ... Oxygen is a non-metallic element of atomic number 8. Its symbol is O, the atomic weight is 15.9994, the specific gravity is ...
Characteristics of oxygen isotope substitutions in the quasiparticle spectrum of Bi2Sr2CaCu2O8+. E. Schachinger1, J. P. ... We find that not only can we account for the shifts of the kink energy seen on oxygen isotope substitution but also get a ...
The key objectives of this project were as follows: (1) to validate the combined use of Cl and O stable isotope ratio analysis ... Stable isotope ratio analysis of chlorine and oxygen in the perchlorate molecule were employed as the primary forensic tool to ... Validation of Chlorine and Oxygen Isotope Ratio Analysis to Differentiate Perchlorate Sources and to Document Perchlorate ... Validation of Chlorine and Oxygen Isotope Ratio Analysis To Differentiate Perchlorate Sources and to Document Perchlorate ...
... Schimmelmann, A ... Katsura, H. 2012: Latitude Effect on Carbon, Nitrogen and Oxygen Stable Isotope Ratios in Foliage and in Nitric-oxide Ions of ... Strathearn Gary, E. 1988: Determination of the rate of atmospheric oxygen accumulation determined from stable hydrogen isotope ... Murad Ahmed, A.; Krishnamurthy, R.V. 2008: Factors controlling stable oxygen, hydrogen and carbon isotope ratios in regional ...
Paleoclimate Studies on Bykovsky Peninsula, North Siberia - Hydrogen and Oxygen Isotopes in Ground Ice Meyer, Hanno ORCID: ... Hydrogen and Oxygen Isotopes in Ground Ice , Polarforschung, Bremerhaven, Alfred Wegener Institute for Polar and Marine ...
Dispersion of Radionuclides and Oxygen Isotopes , International Conference on Isotopes in Environmental Studies - Aquatic Forum ... Tracer Studies with Arctic and Subarctic Coupled Ice-ocean Models: Dispersion of Radionuclides and Oxygen Isotopes Karcher, ...
The chert-water oxygen isotope fractionation with temperature was estimated from published experimental data and from the ... Knauth, LeRoy Paul (1973) Oxygen and hydrogen isotope ratios in cherts and related rocks. Dissertation (Ph.D.), California ... and the somewhat insensitive chert-calcite oxygen isotope fractionation thus cannot be used to obtain meaningful temperatures. ... The isotope data indicate that, for many darts, the diagenetic, transformation of opal to granular microcrystalline quartz ...
Stable oxygen isotope ratio of Globigerinoides sacculifer from sediment core ERDC-093P. Scripps Institution of Oceanography, UC ... Berger, Wolfgang H; Yasuda, Memorie K; Bickert, Torsten; Wefer, Gerold (1996): (Table A2) Stable oxygen isotope ratio of ...
... depth of deep-dwelling planktonic foraminifera from the eastern North Atlantic constrained by stable oxygen isotope ratios of ...
Provides links to USGS information about oxygen isotope analysis and related topics. Provides a topical browse interface into ... stable isotope data from the Elizabeth copper mine Superfund site, Vermont, USA Stable hydrogen, oxygen, and sulfur isotope ... Experimental determination of the proportion of a given stable oxygen isotope in a sample. ... Geochemistry, geochronology, and isotope geochemistry data for zircons and zircon-hosted melt and mineral inclusions in the St ...
Fractionation of the three stable oxygen isotopes by oxygen-producing and oxygen-consuming reactions in photosynthetic ... Oxygen isotope composition of waters recorded in carbonates in strong clumped and oxygen isotopic disequilibrium Caroline ... We analysed the oxygen isotope composition of bones and teeth of four marine species possessing regional heterothermies. We ... Guy, R. D., Fogel, M. L., and Berry, J. A.: Photosynthetic fractionation of the stable isotopes of oxygen and carbon, Plant ...
Isotopes of elements such as neon and magnesium that are slightly heavier than oxygen do not seem to sport closed shells when ... An illustration of the protons (red) and neutrons (blue) in an oxygen-28 nucleus, which was found to quickly shed four neutrons ... The instability of oxygen-28 suggests that its neutrons are not packed into neatly filled shells. ... With powerful facilities, including RIKEN and the new Facility for Rare Isotope Beams, nuclear physicists should have ample ...
The following pages link to Movie:Floodplain evolution: incision/aggradation history based on oxygen isotope curve: Displayed 2 ... Pages that link to "Movie:Floodplain evolution: incision/aggradation history based on oxygen isotope curve". From CSDMS ...
The following pages link to Movie:Floodplain evolution: incision/aggradation history based on oxygen isotope curve: Displayed 2 ... Pages that link to "Movie:Floodplain evolution: incision/aggradation history based on oxygen isotope curve". From CSDMS ...
... Cortina-Gil, D.; Fernández-Vázquez, J.; Aumann, T.; Baumann, T.; Benlliure, J.; ... have been used as a spectroscopic tool for obtaining information about the ground state of neutron-rich oxygen isotopes. Using ...
... iga st henry ohio gels kitchen isotopes of xenon isotopes of ytterbium isotopes that decay slowly are used to date isotopes ... iga st henry ohio gels kitchen isotopes of xenon isotopes of ytterbium isotopes that decay slowly are used to date isotopes ...
... pdf isotopes of hydrogen-1 isotopes of lead isotopes of oxygen isotopes of silver isotopes of sr isotopes of strontium isotopes ... differ in their isotopes of bromine isotopes of carbon isotopes of element 88 isotopes of gold isotopes of hydrogen isotopes of ... mirna exosomes msc exosomes nj exosomes tem exosomes therapy exosomes treatment isotopes definition isotopes means isotopes of ... of xenon isotopes of yttrium isotopes park isotypes bio meaning isotypes of antibodies isotypes of antibodies and their ...
Since the first discovery of isotopes of elements 100 years ago, the ... Bao, H. (2019). Triple oxygen isotopes. Triple Oxygen Isotopes, 1-26. https://doi.org/10.1017/9781108688543 ... Since the first discovery of isotopes of elements 100 years ago, the "detective" power of stable isotopes for processes that ... and 18O for oxygen. This Element focuses on the history of discovery of triple isotope effects, the conceptual framework behind ...
Oxygen and Deuterium Isotopes. Stable isotopes (oxygen δ18O and deuterium, δ2H) are widely used as effective tracers to ... Using the isotope data obtained by these authors for the water from wells in the Rift and Middle Atlas regions (Figure 11B), ... Winckel, A.; Marlin, C.; Dever, L.; Morel, J.-L.; Morabiti, K.; Makhlouf, M.B.; Chalouan, A. Apport des isotopes stables dans ... Recharge altitude estimation of thermal springs using stable isotopes in Morocco». Comptes Rendus Geosci. 2002, 334, 469-474. [ ...
Simulated stable water isotopes during the mid-Holocene and pre-industrial periods using AWI-ESM-2.1-wiso X. Shi et al. 10.5194 ... Simulated stable water isotopes during the mid-Holocene and pre-industrial periods using AWI-ESM-2.1-wiso X. Shi et al. 10.5194 ... Investigating stable oxygen and carbon isotopic variability in speleothem records over the last millennium using multiple ... Modeled isotope variations mostly arise from temperature differences. While lower-resolution speleothems do not capture extreme ...
... isotopes of copper, isotopes of hydrogen, isotopes of lead, isotopes of nitrogen, isotopes of oxygen, isotopes of oxygen-16, ... isotopes of rhenium, isotopes of sulfur, isotopes of uranium, isotopes of water, isotopes of xenon, isotopes of ytterbium, ... isotopes and ions, isotopes baseball, isotopes baseball abq, isotopes definition, isotopes examples, isotopes of argon, ... isotopes that decay slowly are used to date, isotopes website, isotypes bio meaning, isotypes of antibodies, isotypes of ...
3.4.2. Sulfur and Oxygen Isotopes in Barite. The δ18O and δ34S barite bulk sample data are given in Table 2 and SIMS data in ... Turchyn, A.V.; Schrag, D.P. Oxygen isotope constraints on the sulphur cycle over the past 10 million years. Science 2004, 303, ... Stable Isotopes. 3.4.1. Carbon Isotopes. The δ13C data obtained on bulk samples of the barite-quartz interface are given in ... Turchyn, A.V.; Schrag, D.P. Cenozoic evolution of the sulphur cycle: Insight from oxygen isotopes in marine sulfate. Earth ...
The k values estimated from nighttime variations in oxygen isotopes are found to be higher than the direct estimations at low ... we report here the results of the first ever application of the natural abundance of triple isotopes of dissolved oxygen (sup( ...
Costa A, Cherubini P, Graça J, Spiecker H, Barbosa I, Máguas C. Beyond width and density: stable carbon and oxygen isotopes in ... Dive into the research topics of Beyond width and density: stable carbon and oxygen isotopes in cork-rings provide insights of ... Beyond width and density: stable carbon and oxygen isotopes in cork-rings provide insights of physiological responses to water ... In this study, we address the relation between carbon and oxygen stable isotopes of cork rings and precipitation and ...
According to the instability of oxygen-28, its neutrons are not arranged properly in the shells. Maria Goeppert Mayer in the ... Is the Magic of the Neutron-Rich Oxygen Isotope Real? , ... Is the Magic of the Neutron-Rich Oxygen Isotope Real?. Is the ... Is the Magic of the Neutron-Rich Oxygen Isotope Real - Illustration of protons (red) and neutrons (blue) in the oxygen-28 ... Although they are slightly heavier than oxygen, isotopes of elements such as neon and magnesium do not appear to have closed ...
  • Solid samples (organic and inorganic) for oxygen isotopic ratios are usually stored in silver cups and measured with pyrolysis and mass spectrometry. (wikipedia.org)
  • This will be achieved by collecting specimens of the planktic foraminifera Globigerinoides ruber and analysing the stable oxygen isotope ratios contained within their calcium carbonate tests (shells). (data.gov.uk)
  • Oxygen isotope ratios provide information about the global ice volume and global climate, and the standard record can be identified world-wide. (data.gov.uk)
  • This dataset contains rosette bottle data from the U.S. Coast Guard Cutter Healy 09-01 cruise in March 2009, including salinity, temperature, macronutrients and stable oxygen isotope ratios. (ucar.edu)
  • Tree -ring carbon and oxygen isotope ratios from live and recently dead trees may reveal important mechanisms of tree mortality . (bvsalud.org)
  • The growth of ice shelves during the "Ice Age" is shown to cause a decreased isotopic ratio at long distances from the edge of an ice shelf because of the fractionation of isotopes as a function of the vertical temperature distribution in the atmosphere and the dispersion of snow by crystal type, fall velocity, and wind fields. (icr.org)
  • Experiments to date indicate that post depositional modification by biodegradation causes a reproducible fractionation factor ratio between O and Cl isotopes in perchlorate ( ε 18 O/ ε 37 Cl = 2.5) that is roughly perpendicular to the area in which mixtures of synthetic and Chilean ClO 4 - plot in dual isotope plots. (serdp-estcp.org)
  • The chert-water oxygen isotope fractionation with temperature was estimated from published experimental data and from the isotopic compositions of cherts which formed at approximately known temperatures. (caltech.edu)
  • Cherts are usually not in isotopic equilibrium with their coexisting carbonates, and the somewhat insensitive chert-calcite oxygen isotope fractionation thus cannot be used to obtain meaningful temperatures. (caltech.edu)
  • The team isolated and channeled the 29 F toward a reservoir of liquid hydrogen, which on occasion would knock off a proton from the incoming isotopes to form 28 O. The trickiest part was confirming the presence of the neutron-rich isotope. (aip.org)
  • The hardest part was proving that the neutron-rich isotope was actually there. (optimumphysics.com)
  • The first is by far the most abundant, constituting 99.763% of all oxygen atoms occurring in nature. (jrank.org)
  • Oxygen-17 makes up an additional 0.037%, and oxygen-18, 0.200% of all oxygen atoms. (jrank.org)
  • The quantum paraelectric strontium titanate can be made ferroelectric through replacing oxygen atoms with their heavy isotopes. (edu.hk)
  • Atoms tend to combine with other atoms to form molecules (for example, hydrogen and oxygen combine to form water). (cdc.gov)
  • The temperature can be recreated by looking at the relationship between different oxygen isotopes (that is, different kinds of oxygen atoms). (lu.se)
  • This trend has been interpreted by the conventional climate community to have occurred over about 100,000 years and is due primarily to changes in oceanic and atmospheric temperatures as the lighter isotope of oxygen is preferentially transferred slowly from the oceans to ice during glaciation and the rapid transfer back to the ocean during deglaciation. (icr.org)
  • The longest-lived radioisotope is 15 O with a half-life of 122.266(43) s, while the shortest-lived isotope is the unbound 11 O with a half-life of 198(12) yoctoseconds, though half-lives have not been measured for the unbound heavy isotopes 27 O and 28 O . mO - Excited nuclear isomer. (wikipedia.org)
  • There are three known stable isotopes of oxygen (8O): 16 O , 17 O , and 18 O . Radioactive isotopes ranging from 11 O to 28 O have also been characterized, all short-lived. (wikipedia.org)
  • A number of radioactive isotopes of the element have also been prepared, the most widely used commercially being oxygen-15, which decays by the emission of a positron with a half life of 122 seconds. (jrank.org)
  • 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)
  • The instability of oxygen-28 suggests that its neutrons are not packed into neatly filled shells. (aip.org)
  • Isotopes that have so-called magic numbers of protons, neutrons, or both are akin to the noble gases: They gain stability because their outermost occupied shells are full, and jumping to the next shell requires considerable energy input. (aip.org)
  • Isotopes of elements such as neon and magnesium that are slightly heavier than oxygen do not seem to sport closed shells when they are packed with 20 neutrons. (aip.org)
  • According to the instability of oxygen-28, its neutrons are not arranged properly in the shells. (optimumphysics.com)
  • Similar to noble gases, isotopes have so-called magic numbers of protons, neutrons, or both, and gain stability by having outermost filled shells because it takes a lot of energy to move to the next shell. (optimumphysics.com)
  • Although they are slightly heavier than oxygen, isotopes of elements such as neon and magnesium do not appear to have closed shells when bombarded with 20 neutrons. (optimumphysics.com)
  • the ratio of two oxygen isotopes, oxygen-16 ( 16 O) and oxygen-18 ( 18 O), which is determined on calcium carbonate from shells of microfossils that accumulated year by year on the seafloor. (britannica.com)
  • The shells are made of calcium carbonate, which means that they mainly consist of the elements calcium, carbon and oxygen. (lu.se)
  • 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 carbon isotopes in the shells tells us about changes in ocean circulation, but also of local changes in upwelling areas. (lu.se)
  • The proportion of oxygen isotopes in the shells reveals changes in global temperature and in global ice volume. (lu.se)
  • Oxygen isotopes in ice cores extracted from polar regions exhibit a decreasing trend in the ratio of the heavy to light isotopes from the beginning of the "Ice Age" to its end, at which point the trend reverses sharply and then remains fairly constant for several thousand years. (icr.org)
  • The key objectives of this project were as follows: (1) to validate the combined use of Cl and O stable isotope ratio analysis as a forensic tool to distinguish sources of perchlorate in groundwater, and (2) to demonstrate the isotopic techniques as a method to verify perchlorate biodegradation in the field. (serdp-estcp.org)
  • Stable isotope ratio analysis of chlorine and oxygen in the perchlorate molecule were employed as the primary forensic tool to identify perchlorate from different sources. (serdp-estcp.org)
  • A method for determining the 18O/16O ratio of organic matter composed of carbon, hydrogen, oxygen, and nitrogen is described. (eurekamag.com)
  • Stable isotopic analyses of carbon, oxygen, and sulfur in multiple rocks and cores of this area refine a model of ore formation in this mineral deposit. (usgs.gov)
  • Calcitic Crinoid fragments in a chert nodule from the Mississippian Burlington limestone yielded an oxygen isotopic temperature of 25°C, indicating that fossil fragments encased within chert nodules may be protected from post-depositional exchange with ground waters and thus suitable for isotopic paleo-temperature analysis. (caltech.edu)
  • We aimed at assessing whether the two climatic factors affect cork-ring isotopic composition under contrasting conditions of water availability, and, therefore, if carbon and oxygen signatures in cork can reflect tree functional (physiological and structural) responses to stressful conditions, which might be aggravated by climate change. (unl.pt)
  • Isotopic techniques offer an incomparable advantage over the traditional tracking methods, as they are non-invasive and do not necessitate the recapture of the same animals," said Leonard Wassenaar, Head of the IAEA's Isotope Hydrology Laboratory . (iaea.org)
  • Then, in 1996, research by Leonard Wassenaar and Keith Hobson, who at the time were isotope scientists for Environment Canada , demonstrated that isotopic techniques can be used to determine the origin of individual animals. (iaea.org)
  • Isotopic research is based on measuring deuterium - a rare isotope of hydrogen - in rainwater, which is directly absorbed by plants or ingested by animals and humans. (iaea.org)
  • We will analyse the upper 7 m of Hole U1396C, at low resolution, for stable oxygen isotopes of the benthic foraminifera Cibicidoides spp. (data.gov.uk)
  • A c. 50 m thick section located in the Crotone Basin (southern Italy) was investigated using oxygen isotopes, pollen and planktonic foraminifera. (unipd.it)
  • A new forensic approach for perchlorate has been developed, based on measurements of the stable isotopes of chlorine ( 37 Cl and 35 Cl) and oxygen ( 18 O, 17 O, and 16 O), and a radioactive chlorine isotope ( 36 Cl) in perchlorate. (serdp-estcp.org)
  • The feasibility of making meaningful measurements of the deuterium content of water extracted from hydrous silica has been evaluated by a series of dehydration and isotope exchange experiments. (caltech.edu)
  • Additionally, to support their claims, both 28 He also 29 Using F measurements, they argue that some of the outermost neutrons of the oxygen nucleus cross the energy gap and flow into another shell, preventing the proper shell closure predicted by theory. (optimumphysics.com)
  • Today, GNIP and its deuterium isotope measurements are widely used to study the migration of many animals, ranging from bats, birds, insects and fish. (iaea.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)
  • These results suggest that although stable isotopes signatures in cork rings are not proxies for net growth, they may be (fairly) robust indicators of trees' physiological and structural adjustments to climate and environmental changes in Mediterranean environments. (unl.pt)
  • Latal, C , Piller, WE & Harzhauser, M 2003, Oxygen and carbon isotope signatures of Miocene molluscs in the Central Paratethys . (elsevierpure.com)
  • Stable hydrogen, oxygen, and sulfur isotope data were collected from surface water, groundwater, and bulk mill tailings samples at this mine in South Strafford, Vermont. (usgs.gov)
  • We focused on nitrogen (N) release from this degradation and associated cycling using N isotopes, an understudied area. (copernicus.org)
  • These continental shelf sediments were previously linked to early cyanobacterial oxygen production, and provide a direct test of conflicting hypotheses concerning the importance of nitrogen oxyanions in the Late Archaean era. (nature.com)
  • Our data reveal a dominantly anaerobic marine nitrogen cycle in which ammonium-replete ferruginous waters underlay an ephemeral oxygen oasis. (nature.com)
  • Restricted oxygen availability could have allowed the upwelling ammonium to reach the photic zone to provide ample nitrogen to fuel a prolific Late Archaean biosphere. (nature.com)
  • Oxygen isotopes are also used to trace ocean composition and temperature which seafood is from. (wikipedia.org)
  • Organic matter (OM) turnover into dissolved inorganic carbon (DIC) was investigated by means of carbon isotope mass balances in Germany's largest water reservoir. (copernicus.org)
  • As some methods of isotope separation enrich not only heavier isotopes of hydrogen but also heavier isotopes of oxygen when producing heavy water, the concentration of 17 O and 18 O can be measurably higher. (wikipedia.org)
  • Furthermore the 17 O(n,α)14 C reaction is a further undesirable result of an elevated concentration of heavier isotopes of oxygen. (wikipedia.org)
  • Therefore facilities which remove tritium from heavy water used in nuclear reactors often also remove or at least reduce the amount of heavier isotopes of oxygen. (wikipedia.org)
  • About 109 kelvin is needed to fuse oxygen into sulfur. (wikipedia.org)
  • In this study, we address the relation between carbon and oxygen stable isotopes of cork rings and precipitation and temperature, in two distinct locations of southwestern Portugal-the (wetter) Tagus basin peneplain and the (drier) Grândola mountains. (unl.pt)
  • Data are provided as delta oxygen-18 values, referenced to Vienna Standard Mean Ocean Water (V-SMOW) and are normalized on the Standard Mean Ocean Water-Standard light Antarctic Precipitation (SMOW-SLAP) scale. (ucar.edu)
  • Here, stable isotope for dew, ambient water vapor, soil water, plant water, creek water, and precipitation were tracked to determine the characteristics of dew from ecohydrological processes in the meadow. (authorea.com)
  • They collected 1200 specimens from 13 hibernation colonies and across the continent, checked the patterns of deuterium concentration in the wings and compared them with the IAEA's Global Network of Isotopes in Precipitation (GNIP) database to determine the butterflies' origin and deduct their migration routes. (iaea.org)
  • What is the Global Network of Isotopes in Precipitation (GNIP)? (iaea.org)
  • cellulose extraction and blue-stain fungus on retrospective studies of carbon and oxygen isotope variation in live and dead trees. (bvsalud.org)
  • To shed crucial light on this problem, we carry out both x-ray absorption spectroscopy (XAS) and oxygen isotope effect (OIE) studies on LCMO/YBCO/LCMO trilayers grown by pulsed laser deposition. (aps.org)
  • We find that not only can we account for the shifts of the kink energy seen on oxygen isotope substitution but also get a quantitative estimate of the fraction of the area under the electron-boson spectral density which is due to phonons. (edpsciences.org)
  • We have measured the effect of oxygen isotope substitution on the ab-plane reflectance of underdoped YBa(2)Cu(3)O(7-delta). (mcmaster.ca)
  • The frequency shift of the transverse optic phonons due to the substitution of 16O by 18O yields an isotope effect of the expected magnitude for copper-oxygen stretching modes with alpha=0.5+/-0.1. (mcmaster.ca)
  • Heaviest particle-bound isotope of oxygen, see Nuclear drip line Natural oxygen is made of three stable isotopes, 16 O , 17 O , and 18 O , with 16 O being the most abundant (99.762% natural abundance). (wikipedia.org)
  • With powerful facilities, including RIKEN and the new Facility for Rare Isotope Beams , nuclear physicists should have ample opportunity to probe more nuclei that are chock-full of neutrons. (aip.org)
  • Nuclear physicists will have many opportunities to study other nuclei full of neutrons, thanks to powerful facilities such as RIKEN and the soon-to-be-built Rare Isotope Beam Facility. (optimumphysics.com)
  • This project will focus on techniques for and analysis of some of the lightest elements and isotopes (H, B, C, O) with non-conventional nuclear reaction techniques. (lu.se)
  • In addition to Cl and O isotopes of perchlorate, there are a large number of supporting methods/analyses available as forensic lines of evidence to help identify sources of perchlorate (or other contaminants) in a groundwater environment. (serdp-estcp.org)
  • Granular microcrystalline quartz, the most common constituent of chert, has been found to contain hydroxyl groups particularly suitable for hydrogen isotope analyses. (caltech.edu)
  • Experimental determination of the proportion of a given stable oxygen isotope in a sample. (usgs.gov)
  • A rapid liquid chromatography tandem mass spectrometry (LC-MS/MS) method has been developed for determination of levels of the organophosphorus (OP) pesticides chlorpyrifos (CPF), azinphos methyl (AZM), and their oxygen analogs chlorpyrifos-oxon (CPF-O) and azinphos methyl-oxon (AZM-O) on common active air sampling matrices. (cdc.gov)
  • Due to natural oxygen being mostly 16 O, samples enriched with the other stable isotopes can be used for isotope labeling. (wikipedia.org)
  • Samples were equilibrated with carbon dioxide and analyzed on a Thermo Delta Plus stable isotope mass spectrometer using continuous flow of ultra high purity helium. (ucar.edu)
  • The researchers developed an intricate experimental setup at the RIKEN Radioactive Isotope Beam Factory in Wako, Japan, specifically to produce and detect 28 O. They fired an intense beam of neutron-rich calcium nuclei at a beryllium target to produce a plethora of species, including fluorine-29, which is identical to 28 O save for an extra proton. (aip.org)
  • 28 To produce and detect O, researchers created a complex experimental setup at the RIKEN Radioactive Isotope Beam Factory in Wako, Japan. (optimumphysics.com)
  • Climatic patterns revealed by pollen and oxygen isotope records across the Brunhes-Matuyama Boundary in central Mediterranean (Southern Italy). (unipd.it)
  • the triple-alpha process creates 12 C , which captures an additional 4 He nucleus to produce 16 O . The neon burning process creates additional 16 O . Both 17 O and 18 O are secondary isotopes, meaning their synthesis requires seed nuclei. (wikipedia.org)
  • Estimating of gas transfer velocity using triple isotopes of dissolved oxygen. (nio.res.in)
  • Based on observations in the northwestern subarctic Pacific and Sagami Bay, we report here the results of the first ever application of the natural abundance of triple isotopes of dissolved oxygen (sup(16)O, sup(17)O and sup(18)O) for direct estimation of k and propose a new relationship with wind speed. (nio.res.in)
  • How is the isotopes research conducted and what did it reveal about the monarch butterfly migration path? (iaea.org)
  • For example, it was proven, that the oxygen released in photosynthesis originates in H2O, rather than in the also consumed CO2, by isotope tracing experiments. (wikipedia.org)
  • Most 18 O is produced when 14 N (made abundant from CNO burning) captures a 4 He nucleus, becoming 18 F . This quickly (half-life around 110 minutes) beta decays to 18 O making that isotope common in the helium-rich zones of stars. (wikipedia.org)
  • An illustration of the protons (red) and neutrons (blue) in an oxygen-28 nucleus, which was found to quickly shed four neutrons. (aip.org)
  • Is the Magic of the Neutron-Rich Oxygen Isotope Real - Illustration of protons (red) and neutrons (blue) in the oxygen-28 nucleus, this nucleus has been found to rapidly eject four neutrons. (optimumphysics.com)
  • Isotopes are forms of the same element, but differ in the number of neutrons within the nucleus. (cdc.gov)
  • In the late 1940s, Maria Goeppert Mayer noticed that nuclei containing certain numbers of protons or neutrons-specifically, 2, 8, 20, 28, 50, and 82-tend to be more stable than similarly composed isotopes. (aip.org)
  • Team 29 He separated the F and directed it into a pool of liquid hydrogen, which occasionally released protons of one of the incoming isotopes. (optimumphysics.com)
  • Ice and water normally have different distributions of the different oxygen isotopes, so it is possible to see that the balance has varied if there has been a lot of ice (cold climate) or lots of water (warm climate). (lu.se)
  • The latest evidence was produced by a team led by scientists at the Tokyo Institute of Technology who created and measured oxygen-28 nuclei for the first time. (optimumphysics.com)
  • The latest evidence comes from a team, led by researchers at the Tokyo Institute of Technology, that has produced and measured oxygen-28 nuclei for the first time. (aip.org)
  • abstract = "Vibrational lifetimes of the asymmetric stretch mode (1136 cm-1) of oxygen in silicon are measured using pump-probe spectroscopy and calculated by ab initio theory. (ttu.edu)
  • Finally we will work on new techniques for hydrogen and oxygen isotope measurement for Geoscience applications. (lu.se)
  • A sensitive LC-MS/MS method for measurement of organophosphorus pesticides and their oxygen analogs in air sampling matrices. (cdc.gov)
  • Our statistical analysis determines the role of dew in an alpine graminoid-Kobresia meadow in the northern Qinghai-Tibet Plateau, which provides an improved understanding of dew formation based on a stable isotope technology. (authorea.com)
  • N inputs from permafrost degradation and seasonal river N trends were identified using isotopes, helping to predict climate change impacts. (copernicus.org)