Efficiency isotope compositions. Medical search. Frequent questions

For details on experimental sites, leaf and soil sampling and chemical and stable isotope analyses please refer to the Materials and Methods in the paper by Guerrieri et al. (datadryad.org)
While traditional stable isotope analyses of tooth enamel (e.g., carbon and oxygen) and trace element ratios (e.g. (blueskytccaalibaba.com)

This session aims to bring together scientists from different fields applying single and dual oxygen and hydrogen isotope approaches on environmental-derived compounds for the reconstruction of climatic and biological processes that go beyond standard isotope analyses of water. (copernicus.org)
We performed geochemical (elemental abundance and stable Si isotopes, δ30Si) and microscopic (X-ray diffraction and scanning electron microscope) analyses to monitor leaching efficiency in separating different Si phases. (lu.se)

In this paper, hydrogen-oxygen and carbon stable isotope technology, and physiological index measurements were applied to determine the leaf traits, water-use efficiency, and photosynthetic characteristics of Impatiens hainanensis leaves in dry and foggy seasons, hoping to expound the adaptation mechanism of I. hainanensis leaves to the water dynamics in dry and foggy seasons. (mdpi.com)
as well, leaf and soil stable N isotope composition (δ15N) and total %N were used to assess changes in N availability. (datadryad.org)
Water-use efficiency is typically measured with an instrument that clamps to leaves and monitors the flux of carbon dioxide and water vapor moving into and out of the leaf. (vistacomm.com)
The article , "Leaf stable carbon isotope composition reflects transpiration efficiency in Zea mays," is published in The Plant Journal [DOI: 10.1111/tpj.14135]. (vistacomm.com)
The oxygen and hydrogen isotopic composition δ 2 H and δ 18 O of leaf and lake water reflects the isotopic composition of source water/precipitation modified by evapo(transpi)rative enrichment. (copernicus.org)
In our contribution, we discuss the potential, the advances and the limitation of the coupled isotope approach based on leaf wax-derived n -alkane and hemicellulose-derived sugar biomarkers (δ 2 H n -alkanes - δ 18 O sugars ). (copernicus.org)
A significant contribution of g mes to leaf carbon isotope discrimination values was observed. (afs-journal.org)

Sulfur isotope analysis has been used to investigate sources and chemical processes of sulfur dioxide and sul- fate in the atmosphere, however interpretation of measured sulfur isotope ratios is challenging due to a lack of reliable information on the isotopic fractionation involved in ma- jor transformation pathways. (documents.pub)
And it shows that inbred lines whose carbon ratios are within a certain range may have greater water-use efficiency, although it's too early to say how this will play out in hybrids. (vistacomm.com)
Molybdenum and tungsten are redox-sensitive elements, and their stable isotope ratios have attracted attention as paleoceanographic proxies. (frontiersin.org)
In this study, we provided the concentrations and isotope ratios of dissolved Mo and W in the oceans (the North Pacific and Indian Oceans), marginal seas (the East China Sea and Sea of Japan), and a river-estuary system in Japan (from the Uji-Yodo rivers to Osaka Bay). (frontiersin.org)
Among Mo isotope ratios, the 98 Mo/ 95 Mo ratio is conventionally used as a tracer. (frontiersin.org)
The bidirectional stable nitrogen isotope tracer technique quantified the proportions of assimilated nitrate and ammonium in Brassica napus plantlets grown at different ammonium/nitrate ratios. (biomedcentral.com)
The utilization proportions of sucrose and CO 2 could be quantified by a two end-member isotope mixing model for Bn plantlets grown at different ammonium/nitrate ratios. (biomedcentral.com)
Quantifying the utilization proportions of nitrate, ammonium, sucrose and CO 2 can reveal the difference in the ammonium/nitrate use efficiency for new C input derived from CO 2 assimilation/sucrose utilization for plantlets grown at variable ammonium/nitrate ratios. (biomedcentral.com)

Sulphur isotopic compositions of sulphide and gangue minerals are consistent with similar data sets from other highsulphidation deposits. (unige.ch)
Variations in Sr and Pb isotope data among the deposits are interpreted in terms of fluid interaction with different host-rocks, additionally variability in Pb isotopic compositions can be attributed to differences in composition of the associated magmatism. (unige.ch)
Particulate fluxes and isotopic compositions were similar in both deep and shallow sediment traps, highlighting that most remineralisation occurred in the upper 400 m of the water column. (copernicus.org)
Differences in the seasonal cycles of isotopic compositions of C, N, and Si provide insights into the degree of coupling of these key nutrients. (copernicus.org)
The change in the nutrient and remineralisation regimes, indicated by the different isotopic compositions of the spring and summer productive periods, suggests a change in the source region of material reaching the traps and associated shifts in phytoplankton community structure. (copernicus.org)

Summary Tree-ring stable isotopes integrate crown transpiration rates and photosynthesis rates and may enhance our under- standing of tree vitality. (sagepub.com)

In the measurement of ionising radiation the counting efficiency is the ratio between the number of particles or photons counted with a radiation counter and the number of particles or photons of the same type and energy emitted by the radiation source. (wikipedia.org)
In contrast, the nitrogen (N) isotope ratio of organic material (expressed as δ 15 N vs. AIR in ‰, where δ 15 N = [( 15 N/ 14 N sample / 15 N/ 14 N reference ) − 1] × 1000) derived from bulk tissues or specific compounds (e.g., amino acids) is a widely used proxy for the dietary and trophic behavior of animals in terrestrial and marine food webs. (blueskytccaalibaba.com)
For many plants, the ratio of 12C-to-13C is indicative of their water-use efficiency. (vistacomm.com)

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)
We also encourage people working with all techniques (IRMS-, NMR- or spectroscopy-based) to present advances in methods, as well as researchers focusing on improving oxygen and hydrogen isotope-based models to discuss their approaches. (copernicus.org)
In summary, the session will offer an overview on oxygen and hydrogen applications across different ecosystems in order to facilitate the interpretation of compound-specific isotope patterns. (copernicus.org)

It is based on canopy conductance inferred from sap flux and intrinsic water-use efficiency estimated from the stable carbon isotope composition of phloem contents. (duke.edu)
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)

Intrinsic water use efficiency in wet and dry years at young and old plantations of Pinus sylvestris var. (afs-journal.org)

The research paper , "Diminishing Co-2-driven gains in water-use efficiency of global forests," has been published in Nature Climate Change . (phys.org)
Diminishing CO2-driven gains in water-use efficiency of global forests, Nature Climate Change (2020). (phys.org)
If this is the case, then stable isotopes, where forests are considered a symbolic part of the cultural which integrate information about stomatal activity and pho- identity [5], citizens were shocked and in some cases there tosynthesis, should be a much better indicator of tree vitality was even panic, incited by environmentalist movements sup- than more commonly used indicators such as tree-ring width ported by poor or nonexistent science. (sagepub.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)
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)
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)

Repeated measurements of C-13 in breath CO2 provide us with a profile of the timing and efficiency of oxidation of the labeled fuel. (usda.gov)
The results presented in this study will be par- ticularly useful to determine the importance of the transition metal-catalysed oxidation pathway compared to other oxida- tion pathways, but other main oxidation pathways can not be distinguished based on stable sulfur isotope measurements alone. (documents.pub)

20 C-atoms) (δ13C-FAs) have been increasingly used to apportion sediment sources using isotope mixing models. (rothamsted.ac.uk)
In this study we examine sediment-trap-derived particle fluxes and stable isotope signatures of carbon (C), nitrogen (N), and biogenic silica (BSi) at a study site in the biologically productive waters of the northern Scotia Sea in the Southern Ocean. (copernicus.org)

Estimating discrimination against 13 C during photosynthesis at landscape, regional, and biome scales is difficult because of large-scale variability in plant stress, vegetation composition, and photosynthetic pathway. (escholarship.org)

Scholars@Duke publication: Estimating canopy gross primary production by combining phloem stable isotopes with canopy and mesophyll conductances. (duke.edu)

When attempting to improve a certain trait, in this case water-use efficiency, breeders grow a diverse set of corn lines and screen them to find natural variation in the trait. (vistacomm.com)
Also, an attempt was made to test the efficiency of hormones as well as the variation in response among different clones. (silvafennica.fi)

The richness and composition of AM fungi communities depend on the host plant, climate, and soil conditions. (rodaleinstitute.org)

Since we observed isotopically light particulate material in the traps in summer, we suggest physically mediated replenishment of lighter isotopes of key nutrients from depth, enabling the full expression of the isotopic fractionation associated with biological uptake. (copernicus.org)

Despite the potential of nitrogen isotopes for trophic reconstruction, their application in the paleontological record has been limited due to the poor preservation of N-containing organic matter. (blueskytccaalibaba.com)

In this study, we show that the nitrogen isotope composition of organic matter preserved in mammalian tooth enamel (δ 15 N enamel ) records diet and trophic position. (blueskytccaalibaba.com)
In the process of sewage treatment, the characteristics of dissolved organic matter (DOM) are always changed during chemical and biological processes, affecting the generation of disinfection by-products (DBPs) compositions at the following disinfection stage. (mdpi.com)
However, large uncertainties still exist concerning the sources, lability, age, and composition of the organic matter associated with FeR in natural sediments. (worktribe.com)
Here we use radiocarbon (Δ14C) and stable isotopes (δ13C) of downcore bulk sedimentary organic matter, benthic foraminifera and the organic carbon fraction bound to FeR to interrogate the source and age of the organic carbon pool associated with FeR in Arctic marine sediments. (worktribe.com)

Increased food production and enhanced sustainability depend on improving nitrogen-use efficiency (NUE) of crops. (bioone.org)
Hence, excessive nitrate in MS medium is not optimal and causes a waste of inorganic N. Considering the fact that the concentration of nitrate was twice that of ammonium in MS medium (20 mM ammonium, 40 mM nitrate), optimizing the nitrate concentration will effectively improve the nitrogen use efficiency of plantlets. (biomedcentral.com)

Studies in our laboratory include in-depth biological examinations of the impact of different dietary factors on biochemical and neurological factors involved in energy regulation and body composition, chemical studies of food composition, and randomized controlled trials testing practical interventions that can be scaled for population-wide benefits. (usda.gov)
Department of Environmental, Biological and Pharmaceutical Stable isotope analysis of tree rings provides a powerful Sciences and Technologies, University of Campania "L. Vanvitelli", method to assess physiological processes in trees retrospec- Via Vivaldi 43, I-81100 Caserta, Italy tively and to understand the role played by drought in forest Departme nt of Forest Resources Management, Faculty of Forestry, decline episodes. (sagepub.com)
Consequently, the biological effect of ammonium/nitrate utilization, the biological effect of sucrose/CO 2 utilization, and the ammonium/nitrate use efficiency for new C input derived from CO 2 assimilation/sucrose utilization are still unclear for plantlets. (biomedcentral.com)

With our inversion approach, we solved for three ecophysiological parameters of the northern biosphere ( 13 C discrimination, a net primary production light use efficiency, and a temperature sensitivity of heterotrophic respiration (a Q10 factor)) that provided a best fit between modeled and observed δ 13 C and CO 2 . (escholarship.org)

SIP encompasses a series of methods that involve the incorporation of heavy isotopes into newly synthetized DNA and its separation on a density gradient 16 . (nature.com)

1 Introduction Sulfate and sulfur dioxide play an important role in en- vironmental chemistry and climate through their effect on aerosols. (documents.pub)

Recent Findings In the past two decades, tree-ring stable isotopes have been used not only to reconstruct the impact of past climatic events, such as drought, but also in the study of forest decline induced by air pollution episodes, and other natural disturbances and environmental stress, such as pest outbreaks and wildfires. (sagepub.com)

Here, we examine whether increased forest expansion following pastureland abandonment is associated with greater water-use efficiency (WUE) and legacies from previous land use in terms of nitrogen (N) availability. (datadryad.org)

Several factors affect the counting efficiency: The distance from the source of radiation The absorption or scattering of particles by the medium (such as air) between the source and the surface of the detector The detector efficiency in counting all radiation photons and particles that reach the surface of the detector The accompanying diagram shows this graphically. (wikipedia.org)
Proportional counters and end-window Geiger-Muller tubes have a very high efficiency for all ionising particles that reach the fill gas. (wikipedia.org)
However the overall detector efficiency is largely affected by attenuation due to the window or tube body through which particles have to pass. (wikipedia.org)
Now greenhouse gases and particles are rapidly added by human activities, altering the atmospheric composition and therefore also the climate conditions. (lu.se)

Plants often avoid competition by shifting their water use seasonally, which affects the water-use patterns of dominant species as well as the composition and structure of plant communities. (xjegi.com)

Finally, an interesting output is the possibility of a more critical interpretation of the available data on the particle beam cross-sections with the various elements and isotopes 9 that often rely on poorly populated experimental data sets. (nature.com)

We propose using the sap flux/isotope method as an alternative way to estimate canopy GPP, termed GPP iso/SF , at the stand scale and at daily resolution. (duke.edu)

By examining the carbon isotope composition of tree-rings, researchers from Swinburne and the University of California, Davis have compiled the first comprehensive global database for water-use efficiency. (phys.org)

The chlorophyll concentration and the PSII maximum photochemical efficiency of P. deltoides were significantly higher than those of P. cathayana especially under defoliation with salinity stress, which demonstrated stronger damage on P. cathayana . (plant-ecology.com)

However, latitudinal differences in ore deposit characteristics are likely related to emplacements at different depths, differences in degrees of preservation as a function of post-ore tectonics and/or sedimentary processes, efficiency of ore formation, and/or modifications of regional controls during the 14 Ma-long geological evolution of the Panagyurishte district, such as magma petrogenesis and/or tectonic regimes. (unige.ch)

BODY COMPOSITION: 1: Develop and validate stable isotope methodology to that can be utilized to investigate energy regulation related to sarcopenic obesity and frailty in the elderly. (usda.gov)
We also highlight the need to conduct particle-specific (e.g. faecal pellets, phytoplankton detritus, zooplankton moults) isotopic analysis to improve the use of this tool in assessing particle composition of the sinking material and to develop our understanding of the drivers of biogeochemical fluxes. (copernicus.org)

Quantifying the utilization proportions of nitrate and ammonium can reveal the energy efficiency for N assimilation in plantlets grown in mixed N sources. (biomedcentral.com)

In this study, we identified groundnut genotypes with superior symbiotic efficiency, greater pod yield, and plant water-use efficiency from 21 advanced groundnut breeding lines from ICRISAT after testing them at three locations in the Guinea savanna of Ghana over two consecutive years. (frontiersin.org)
Of the 21 genotypes studied, genotype 16 (ICGV 99247) recorded the highest shoot δ 13 C value and was superior in water-use efficiency, which was consistent with stability estimates and mean performance. (frontiersin.org)

Water-use efficiency is a key measure of how much water trees are sending back to the atmosphere. (phys.org)
Water-use efficiency is thus used by modelers to adjust their rainfall and runoff forecasts for the role of the trees, especially in large river basins like the Amazon. (phys.org)
Over the past 100 years, the data shows that the rate at which water-use efficiency increased was greatest during the Great Depression and in the aftermath of World War II-periods of much slower increases in the concentrations of carbon dioxide in the atmosphere. (phys.org)
In the last ten years, however, the rate of increase in water-use efficiency has shrunk to close to zero-the mature trees are no longer acclimating to atmospheric carbon dioxide the way they were 60+ years ago. (phys.org)
If there is a pause in carbon dioxide emissions as a result of reduced economic activity generally, then we may see a rebound in the rate of change in water-use efficiency. (phys.org)
In a past study, we found there's room for improvement in corn's water-use efficiency. (vistacomm.com)

From a rapidly changing commodities market to financing and safety challenges, the pressure for mining operations to increase efficiency, sustainability, and productivity has never been greater. (thermofisher.com)

Our approach includes the use of a single stable isotope administration (C-13 palmitic acid or carbohydrate) and monitoring its disappearance in breath CO2 for several days. (usda.gov)
This new industrial and market related approach makes the tuning of production facilities even more strategic: reliability, safety, timing, product quality, and isotope related extraction issues are becoming mandatory aspects to be analyzed looking at the overall efficiency of the production chain, from the setup of the beamline to the target post-processing. (nature.com)

The results indicate that W has the constant concentration and isotopic composition in the modern ocean as well as Mo. (frontiersin.org)

Looking at cyclotron solid targets, uncertainties of the particle beam, material composition and geometry play a crucial role in determining the results. (nature.com)

Detrimental sources of background are the primordial isotopes \(^{232}\) Th, \(^{238}\) U, \(^{235}\) U, \(^{40}\) K and their progeny, as well as \(^{60}\) Co and \(^{137}\) Cs. (springer.com)

Our inversion analysis suggests that Q10 and light use efficiency values that minimize the cost function covary. (escholarship.org)
Analysis of 16S rRNA sequences from BONCAT-positive cells recovered by fluorescence-activated cell sorting (FACS) reveals that the phylogenetic composition of the active fraction is distinct from the total population of extractable cells. (nature.com)

The radical chain reaction mechanism was the only measured reaction that had a faster rate for the light isotopes. (documents.pub)
Verify the composition of piping, valves, and reaction vessels in seconds, with the lowest LODs available. (thermofisher.com)

Poor counting efficiency can be caused by an extremely low energy to light conversion rate, (scintillation efficiency) which, even optimally, will be a small value. (wikipedia.org)
The optimal light use efficiency was 0.47 gC MJ −1 photosynthetically active radiation, and the optimal Q10 value was 1.52. (escholarship.org)

In these animal studies we will determine body composition, energy expenditure, insulin glucose homeostasis, fat absorption, hepatic steatosis, and in liver and intestine tissues gene expression will be determine. (usda.gov)

Anatomy10

Organisms13

Diseases2

Chemicals and Drugs59

Analytical, Diagnostic and Therapeutic Techniques and Equipment37

Psychiatry and Psychology2

Phenomena and Processes73

Disciplines and Occupations7

Anthropology, Education, Sociology and Social Phenomena1

Technology, Industry, Agriculture9

Humanities1

Information Science6

Health Care19

Geographicals1

Stable isotope analyses2

Analyses2

Leaf7

Ratios8

Isotopic compositions5

Transpiration1

Ratio3

Oxygen3

Conductance2

Intrinsic1

Forests3

Radioactive3

Oxidation2

Sediment2

Variability1

Mesophyll1

Variation2

Soil1

Lighter1

Reconstruction1

Organic matter4

Nitrogen-use efficiency2

Biological3

Discrimination1

Newly1

Sulfur1

Environmental1

Greater water-use efficiency1

Particles4

Patterns1

Interpretation1

Canopy1

Researchers1

Chlorophyll1

Processes1

Develop2

Reveal1

Genotypes2

Water6

Sustainability1

Approach2

Concentration1

Uncertainties1

Sources1

Analysis2

Reaction2

Light2

Studies1