scholarly journals Maintaining consistent traceability in high precision isotope measurements of CO<sub>2</sub>: verifying atmospheric trends of δ<sup>13</sup>C

2012 ◽  
Vol 5 (3) ◽  
pp. 4003-4040 ◽  
Author(s):  
L. Huang ◽  
A. Chivulescu ◽  
D. Ernst ◽  
W. Zhang ◽  
Y.-S. Lee
Keyword(s):  
High Precision ◽  
Mean Value ◽  
Rate Of Change ◽  
Atmospheric Co2 ◽  
Precision Measurements ◽  
Total Change ◽  
History Of ◽  
Ambient Measurements ◽  
Isotope Measurements ◽  
Δ13c And Δ18o

Abstract. Maintaining consistent traceability of high precision measurements of CO2 isotopes is critical in being able to observe accurate atmospheric trends of δ13C (CO2). Although a number of laboratories/organizations around the world have been involved in baseline measurements of atmospheric CO2 isotopes for several decades, the reports on their traceability measures are rare. In this paper, a principle and an approach for the traceability maintenance of high precision isotope measurements (δ13C and δ18O) in atmospheric CO2 is described. The uncertainties of the traceability have been estimated based on the history of annual calibrations over the last 10 yr. The overall uncertainties of CO2 isotope measurements for individual ambient samples carried out by our program at Environment Canada are estimated (excluding the uncertainty associated with the sampling). The values are 0.02‰ and 0.05‰ in δ13C and δ18O, respectively, close to the WMO targets for data compatibility. The annual rate of change in δ13C of the primary anchor used in our program (which is the laboratory standard linking ambient measurements back to the primary VPDB scale) is close to zero (−0.0016 ± 0.0012‰ per year) over the period of 10 yr (2001–2011). The average annual decreasing rate of δ13C in air CO2 measurements at Alert over the period from 1999 to 2010 has been confirmed and verified, which is −0.025 ± 0.003‰ per year. The total change of δ13C in the annual mean value during this period is ∼−0.27‰. The concept of "Big Delta" is introduced and its role in maintaining traceability of the isotope measurements is described and discussed extensively. Finally, the challenges and a strategy for maintaining traceability are also discussed and suggested.

scholarly journals Maintaining consistent traceability in high-precision isotope measurements of CO<sub>2</sub>: a way to verify atmospheric trends of δ<sup>13</sup>C and δ<sup>18</sup>O

2013 ◽  
Vol 6 (7) ◽  
pp. 1685-1705 ◽  
Author(s):  
L. Huang ◽  
A. Chivulescu ◽  
D. Ernst ◽  
W. Zhang ◽  
A.-L. Norman ◽  
...  
Keyword(s):  
High Precision ◽  
Fossil Fuel ◽  
Atmospheric Co2 ◽  
Precision Measurements ◽  
Environment Canada ◽  
Total Change ◽  
Rates Of Change ◽  
The World ◽  
Isotope Measurements ◽  
Δ13c And Δ18o

Abstract. Maintaining consistent traceability of high-precision measurements of CO2 isotopes is critical in order to obtain accurate atmospheric trends of δ13C and δ18O (in CO2). Although a number of laboratories/organizations around the world have been conducting baseline measurements of atmospheric CO2 isotopes for several decades, reports on the traceability and maintenance are rare. In this paper, a principle and an approach for maintaining consistent traceability in high-precision isotope measurements (δ13C and δ18O) of atmospheric CO2 are described. The concept of Big Delta is introduced and its role in maintaining traceability of the isotope measurements is described and discussed extensively. The uncertainties of the traceability have been estimated based on annual calibration records over the last 10 yr. The overall uncertainties of CO2 isotope measurements for individual ambient samples analyzed by the program at Environment Canada have been estimated (excluding these associated with the sampling). The values are 0.02 and 0.05‰ in δ13C and δ18O, respectively, which are close to the World Meteorological Organization (WMO) targets for data compatibility. The annual rates of change in δ13C and δ18O of the primary anchor (which links the flask measurements back to the VPDB-CO2 scale) are close to zero (−0.0016 ± 0.0012‰, and −0.006 ± 0.003‰ per year, respectively) over a period of 10 yr (2001–2011). The average annual changes of δ13C and δ18O in air CO2 at Alert GAW station over the period from 1999 to 2010 have been evaluated and confirmed; they are −0.025 ± 0.003‰ and 0.000 ± 0.010‰, respectively. The results are consistent with a continuous contribution of fossil fuel CO2 to the atmosphere, having a trend toward more negative in δ13C, whereas the lack of change in δ18O likely reflects the influence from the global hydrologic cycle. The total change of δ13C and δ18O during this period is ~0.27‰ and ~0.00‰, respectively. Finally, the challenges and recommendations as strategies to maintain a consistent traceability are described.

Hereditary Heparin Cofactor II Deficiency and the Risk of Development of Thrombosis

1987 ◽  
Vol 57 (02) ◽  
pp. 196-200 ◽  
Author(s):  
R M Bertina ◽  
I K van der Linden ◽  
L Engesser ◽  
H P Muller ◽  
E J P Brommer
Keyword(s):  
Liver Disease ◽  
Venous Thrombosis ◽  
Healthy Volunteers ◽  
Mean Value ◽  
Age Group ◽  
Normal Range ◽  
Heparin Cofactor Ii ◽  
History Of ◽  
Group 2 ◽  
Hereditary Nature

SummaryHeparin cofactor II (HC II) levels were measured by electroimmunoassay in healthy volunteers, and patients with liver disease, DIC, proteinuria or a history of venous thrombosis. Analysis of the data in 107 healthy volunteers revealed that plasma HC II increases with age (at least between 20 and 50 years). HC II was found to be decreased in most patients with liver disease (mean value: 43%) and only in some patients with DIC. Elevated levels were found in patients with proteinuria (mean value 145%). In 277 patients with a history of unexplained venous thrombosis three patients were identified with a HC II below the lower limit of the normal range (60%). Family studies demonstrated hereditary HC II deficiency in two cases. Among the 9 heterozygotes for HC II deficiency only one patient had a well documented history of unexplained thrombosis. Therefore the question was raised whether heterozygotes for HC II deficiency can also be found among healthy volunteers. When defining a group of individuals suspected of HC II deficiency as those who have a 90% probability that their plasma HC II is below the 95% tolerance limits of the normal distribution in the relevant age group, 2 suspected HC II deficiencies were identified among the healthy volunteers. In one case the hereditary nature of the defect could be established.It is concluded that hereditary HC II deficiency is as prevalent among healthy volunteers as in patients with thrombotic disease. Further it is unlikely that heterozygosity for HC II deficiency in itself is a risk factor for the development of venous thrombosis.

scholarly journals Anaphylactic Death: A New Forensic Workflow for Diagnosis

Healthcare ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 117
Author(s):  
Massimiliano Esposito ◽  
Angelo Montana ◽  
Aldo Liberto ◽  
Veronica Filetti ◽  
Nunzio Di Nunno ◽  
...  
Keyword(s):  
Clinical History ◽  
Rapid Onset ◽  
Mean Value ◽  
Laryngeal Edema ◽  
Tryptase Level ◽  
Antibody Staining ◽  
Life Threatening ◽  
History Of ◽  
Immunohistochemical Techniques

Anaphylaxis is a life-threatening or fatal clinical emergency characterized by rapid onset, and death may be sudden. The margin of certainty about the diagnosis of anaphylactic death is not well established. The application of immunohistochemical techniques combined with the evaluation of blood tryptase concentrations opened up a new field of investigation into anaphylactic death. The present study investigated eleven autopsy cases of anaphylactic death, carried out between 2005 and 2017, by the Departments of Forensic Pathology of the Universities of Foggia and Catania (Italy). An analysis of the medical records was carried out in all autopsies. Seven autopsies were carried out on males and four on females. Of the eleven cases, one showed a history of asthma, one of food ingestion, two of oral administration of medications, six did not refer any allergy history, and one subject was unknown. All cases (100%) showed pulmonary congestion and edema; 7/11 (64%) of the cases had pharyngeal/laryngeal edema and mucus plugging in the airway; only one case (9%) had a skin reaction that was found during external examination. Serum tryptase concentration was measured in ten cases, and the mean value was 133.5 µg/L ± 177.9. The immunohistochemical examination using an anti-tryptase antibody on samples from the lungs, pharynx/larynx, and skin site of medication injection showed that all cases (100%) were strongly immunopositive for anti-tryptase antibody staining on lung samples; three cases (30%) were strongly immunopositive for anti-tryptase antibody staining on pharyngeal/laryngeal samples; and eight cases (80%) were strongly immunopositive for anti-tryptase antibody staining on skin samples. We conclude that a typical clinical history, blood tryptase level >40 µg/L, and strongly positive anti-tryptase antibody staining in the immunohistochemical investigation may represent reliable parameters in the determination of anaphylactic death with the accuracy needed for forensic purposes.

The availability of copper to grazing ruminants in parts of North Yorkshire

1978 ◽  
Vol 91 (1) ◽  
pp. 13-16 ◽  
Author(s):  
D. I. Givens ◽  
J. R. Hopkins
Keyword(s):  
Mean Value ◽  
Mean Values ◽  
Total Sulphur ◽  
History Of ◽  
Relationship Of

SummaryA total of 225 herbage samples were taken from two areas with a history of bovine hypocupraemia and examined for their Cu, Mo, total S, Zn, Fe and Cd content.In general, the concentrations of Cu and Mo (mean values 10·4 and 1·6 mg/kgD.M. respectively) were normal, as were those of Zn, Fe and Cd (mean values 43, 255 and 0–59 mg/kg D.M. respectively). The total S concentrations (mean value 3·5 g/kg D.M.) were, however, higher than found by some other workers.The concentrations of available herbage Cu were calculated using the following relationship of Suttle & McLauchlan (1976):logTA Cu = –0·0019 Mo–0·0755 S–0·0131 Mo × S–1·153,where TA Cu is the true availability of Cu, and Mo and total sulphur (S) are dietary concentrations as mg/kg D.M. and g/kg D.M. respectively. Animal requirements for available Cu were derived from estimates of the factorial Cu requirements of various classes of livestock, and when these were compared with the calculated concentrations of available Cu in the herbage they provided a possible explanation for the widespread hypocupraemia experienced in these areas.

Prospects for high precision measurements on muonic atoms at the front end of a muon collider

1998 ◽  
Author(s):  
D. Kawall ◽  
M. G. Boshier ◽  
V. W. Hughes ◽  
K. Jungmann ◽  
W. Liu ◽  
...  
Keyword(s):  
High Precision ◽  
Precision Measurements ◽  
Muonic Atoms ◽  
Front End ◽  
Muon Collider

Nasal mucociliary clearance in patients with diabetes mellitus

1989 ◽  
Vol 103 (9) ◽  
pp. 853-855 ◽  
Author(s):  
W. L. Yue
Keyword(s):  
Diabetes Mellitus ◽  
Mucociliary Clearance ◽  
Mean Value ◽  
Nasal Disease ◽  
Patients With Diabetes ◽  
History Of ◽  
Insulin Dependent ◽  
Mucociliary Function ◽  
The Mean ◽  
Nasal Mucociliary Clearance

AbstractFifty insulin-dependent diabetics and 50 non-diabetics without a history of nasal disease have been studied for nasal problems including mucociliary function complicated by diabetes mellitus. For the diabetics, the mean value of nasal mucociliary clearance was considerably decreased and this was more often associated with dry noses but increased pH-values, both of which were higher than those for non-diabetics (p<0.05). As suggested in earlier literature, more aggressive nasal moistening therapy must be recommended for those patients presenting with these conditions in the light of systemic diabetic abnormalities.

Cold atom interferometry for inertial sensing in the field

2020 ◽  
Vol 9 (5) ◽  
pp. 221-225
Author(s):  
Ravi Kumar ◽  
Ana Rakonjac
Keyword(s):  
High Precision ◽  
Cold Atoms ◽  
Cold Atom ◽  
Atom Interferometry ◽  
Precision Measurements ◽  
Inertial Sensing ◽  
Fundamental Physics ◽  
Recent Developments ◽  
Resource Exploration ◽  
Atom Interferometers

AbstractAtom interferometry is one of the most promising technologies for high precision measurements. It has the potential to revolutionise many different sectors, such as navigation and positioning, resource exploration, geophysical studies, and fundamental physics. After decades of research in the field of cold atoms, the technology has reached a stage where commercialisation of cold atom interferometers has become possible. This article describes recent developments, challenges, and prospects for quantum sensors for inertial sensing based on cold atom interferometry techniques.

Analytical Developments for High-Precision Measurements of W Isotopes in Iron Meteorites

2007 ◽  
Vol 79 (8) ◽  
pp. 3148-3154 ◽  
Author(s):  
Liping Qin ◽  
Nicolas Dauphas ◽  
Philip E. Janney ◽  
Meenakshi Wadhwa
Keyword(s):  
High Precision ◽  
Precision Measurements ◽  
Iron Meteorites
Sign in / Sign up

Export Citation Format

Share Document