Allocation of Terrestrial Carbon Sources Using 14CO2: Methods, Measurement, and Modeling

Radiocarbon ◽  
2013 ◽  
Vol 55 (3) ◽  
pp. 1484-1495 ◽  
Author(s):  
Scott J Lehman ◽  
John B Miller ◽  
Chad Wolak ◽  
John Southon ◽  
Pieter P Tans ◽  
...  
Keyword(s):  
Fossil Fuel ◽  
Carbon Sources ◽  
Niwot Ridge ◽  
Sources Of Uncertainty ◽  
Sampling Network ◽  
The Us ◽  
Airborne Sampling ◽  
Background Air ◽  
Measurement Repeatability

The radiocarbon content of whole air provides a theoretically ideal and now observationally proven tracer for recently added fossil-fuel-derived CO2 in the atmosphere (Cff). Over large industrialized land areas, determination of Cff also constrains the change in CO2 due to uptake and release by the terrestrial biosphere. Here, we review the development of a Δ14CO2 measurement program and its implementation within the US portion of the NOAA Global Monitoring Division's air sampling network. The Δ14CO2 measurement repeatability is evaluated based on surveillance cylinders of whole air and equates to a Cff detection limit of <0.9 ppm from measurement uncertainties alone. We also attempt to quantify additional sources of uncertainty arising from non-fossil terms in the atmospheric 14CO2 budget and from uncertainties in the composition of “background” air against which Cff enhancements occur. As an example of how we apply the measurements, we present estimates of the boundary layer enhancements of Cff and Cbio using observations obtained from vertical airborne sampling profiles off of the northeastern US. We also present an updated time series of measurements from NOAA GMD's Niwot Ridge site at 3475 m asl in Colorado in order to characterize recent Δ14CO2 variability in the well-mixed free troposphere.

Bioanalytical Method Development and Validation for the Determination of Vasopressin Receptor Antagonist Conivaptan in Mouse Plasma at NanoLevel and its Pharmacokinetic Application

2019 ◽  
Vol 15 (5) ◽  
pp. 591-598 ◽  
Author(s):  
Haitham Alrabiah ◽  
Ahmed Bakheit ◽  
Sabray Attia ◽  
Gamal A.E. Mostafa
Keyword(s):  
Method Development ◽  
Internal Standard ◽  
Vasopressin Receptor ◽  
Mouse Plasma ◽  
Precipitation Procedure ◽  
Validation Parameters ◽  
The Us ◽  
Method Development And Validation ◽  
Development And Validation

Background: Conivaptan inhibits two of vasopressin receptor (vasopressin receptor V1a and V2). Conivaptan is used for the treatment of hyponatremia, and in some instances, for the treatment of the heart failure. Methods: The present study aimed to develop a simple, sensitive, and accurate HPLC with ultraviolet detection for the assay of conivaptan (CON) in mouse plasma using bisoprolol as internal standard (IS). A precipitation procedure was used to extract CON and the IS from the mouse plasma. CON was chromatographically separated using a C18 analytical column at 25°C. The separation was carried out using a mixture of phosphate buffer (50 mM): acetonitrile (60: 40, v/v, pH 4.5) with a flow rate of 1.0 mL/min and detection was performed at 240 nm. Results: The assay was validated according to the US Food and Drug (FDA) guidelines. The method demonstrated linearity over a concentration range of 150 - 2000 ng/mL (correlation coefficient: r 2 = 0.9985). The mean recovery of CON from the mouse plasma was 101.13%. All validation parameters for CON were within the acceptable range. Conclusion: The investigated method has been shown to be suitable for estimating the CON in plasma samples, and this method is sensitive and highly selective, allowing the estimation of its concentrations up to the nano-scale. The suggested method was successfully used in a pharmacokinetic study of CON in mouse plasma.

scholarly journals Simultaneous Catabolite Repression between Glucose and Toluene Metabolism in Pseudomonas putida Is Channeled through Different Signaling Pathways

2007 ◽  
Vol 189 (18) ◽  
pp. 6602-6610 ◽  
Author(s):  
Teresa del Castillo ◽  
Juan L. Ramos
Keyword(s):  
Glucose Metabolism ◽  
Pseudomonas Putida ◽  
Catabolite Repression ◽  
Carbon Sources ◽  
Flux Analysis ◽  
Glucose Determination ◽  
Net Flux ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Metabolism Gene

ABSTRACT Pseudomonas putida KT2440(pWW0) can use toluene via the TOL plasmid-encoded catabolic pathways and can use glucose via a series of three peripheral chromosome-encoded routes that convert glucose into 6-phosphogluconate (6PG), namely, the glucokinase pathway, in which glucose is transformed to 6PG through the action of glucokinase and glucose-6-phosphate dehydrogenase. Alternatively, glucose can be oxidized to gluconate, which can be phosphorylated by gluconokinase to 6PG or oxidized to 2-ketogluconate, which, in turn, is converted into 6PG. Our results show that KT2440 metabolizes glucose and toluene simultaneously, as revealed by net flux analysis of [13C]glucose. Determination of glucokinase and gluconokinase activities in glucose metabolism, gene expression assays using a fusion of the promoter of the Pu TOL upper pathway to ′lacZ, and global transcriptomic assays revealed simultaneous catabolite repression in the use of these two carbon sources. The effect of toluene on glucose metabolism was directed to the glucokinase branch and did not affect gluconate metabolism. Catabolite repression of the glucokinase pathway and the TOL pathway was triggered by two different catabolite repression systems. Expression from Pu was repressed mainly via PtsN in response to high levels of 2-dehydro-3-deoxygluconate-6-phosphate, whereas repression of the glucokinase pathway was channeled through Crc.

Evaluation of Sources of Uncertainty in Risk Assessments Conducted for the US Army Using a Case Study Approach

2008 ◽  
Vol 4 (1) ◽  
pp. 41 ◽  
Author(s):  
Katherine von Stackelberg ◽  
Donna Vorhees ◽  
Dwayne Moore ◽  
Jerome Cura ◽  
Todd Bridges
Keyword(s):  
Risk Assessments ◽  
Case Study Approach ◽  
Us Army ◽  
Sources Of Uncertainty ◽  
Study Approach ◽  
The Us

scholarly journals The Future of Turkey - United States Relations

Jurnal ICMES ◽  
2018 ◽  
Vol 2 (2) ◽  
pp. 179-196
Author(s):  
Firmanda Taufiq
Keyword(s):  
United States ◽  
The United States ◽  
Economic Interests ◽  
The Us ◽  
The Future ◽  
Foreign Policies ◽  
The Government ◽  
The Cold War ◽  
Role Of The Government

Throughout 2018, relations between Turkey and the United States seemed to deteriorate. The leaders of the two countries issued sharp diplomatic statements and the US even imposed economic sanctions on Turkey. This article aims to analyze how the future of relations between Turkey and the United States. Cooperation between the two has a long historical side after the Cold War. Relations between the two countries are based on various interests, both economic, political, military and security interests. The theory used in this study is the theory of national interest. The US has great interests in the Middle East and Turkey is the front-line ally in achieving those interests. However, there are many US foreign policies that ignore the Turkish concern and create tensions between the two countries. On the contrary, Turkey also has considerable economic interests, but the role of the government elite (in this case, President Erdogan) has a significant influence in the determination of Turkish foreign policy. The findings of this study, although it will go through complex challenges and processes, the US and Turkey will continue to maintain their relations.

Afterword Quilting the Black-Eyed Pea

2019 ◽  
pp. 257-272
Author(s):  
Michael O. West
Keyword(s):  
Social Contract ◽  
The United States ◽  
The Self ◽  
Declaration Of Independence ◽  
The Social ◽  
The Us ◽  
The Republic ◽  
To Come ◽  
A Charge

It is a truism that black folk in the United States are an international people. From the beginning of the republic, they were compelled by force of domestic (national) circumstances to internationalize their struggle for liberation, the founders having excluded them from the US social contract. The initial affidavit of exclusion is right there in the inaugural document of the social contract, the Declaration of Independence, which, ever so cryptically, damned the king of England for having “excited domestic insurrections amongst us.” This was an attack on the self-emancipatory activities of the enslaved descendants of Africa, who were exploiting the chaos caused by the anticolonial rebellion to claim their freedom, sometimes in cahoots with the British colonialists. Unable or unwilling to confront their own contradictions, the authors of the Declaration of Independence condemned the self-determination of the slaves as the doing of outside agitators, a charge that would be hurled at African American movements and activists for generations to come—up to the present time, in fact....

Origins of Marine Corps Aviation

2019 ◽  
pp. 23-60
Author(s):  
Wray R. Johnson ◽  
Wray R. Johnson
Keyword(s):  
World War I ◽  
Marine Corps ◽  
World War ◽  
Small Wars ◽  
The Us

This chapter explores the advent of aviation in the US Marine Corps, beginning with the determination of Alfred A. Cunningham to excite the Corps’ interest in the possibilities of heavier-than-air powered flight. This is followed by an examination of the employment of Marine Corps aviation in World War I, including predeployment training and combat operations. The chapter concludes by addressing the import of this experience, especially with regard to the development of Marine Corps aviation in the small wars era.

scholarly journals Subsidy Determination, Benchmarks, and Adverse Inferences: Assessing ‘Benefit' in US–Coated Paper (Indonesia)

2020 ◽  
Vol 19 (2) ◽  
pp. 216-231
Author(s):  
Eugene Beaulieu ◽  
Denise Prévost
Keyword(s):  
Economic Analysis ◽  
Natural Resources ◽  
Natural Resource ◽  
Benefit Analysis ◽  
Government Ownership ◽  
Coated Paper ◽  
The Us ◽  
Countervailing Duties ◽  
Key Aspects

AbstractThis paper presents a legal-economic analysis of key aspects of the WTO Panel Report involving a challenge by Indonesia against the anti-dumping and countervailing duties imposed by the US on certain coated paper from Indonesia. We focus on the findings in this case relevant to the determination of a ‘benefit’ to the recipient, a core requirement to establish the existence and extent of a subsidy. We examine benchmarking for determining benefit in cases of predominant government ownership of a natural resource and the use of ‘adverse facts available’ against a non-cooperative respondent to infer the existence of a benefit. The benefit analysis in this case may have broader implications. First, it may limit the scope for governments to determine their own policies regarding the ownership and management of natural resources. Second, it may create a loophole allowing investigating authorities to fill gaps in the factual record by intentionally using the ‘facts available’ to the disadvantage of a respondent. In both cases, the panel's findings may open the door to potential misuse of these flexibilities to find a benefit where none exists, or to inflate the margin of benefit to allow for higher countervailing duties.

The first method for determination of lipoyllysine in human urine after oral lipoic acid supplementation

Bioanalysis ◽  
2019 ◽  
Vol 11 (14) ◽  
pp. 1359-1373 ◽  
Author(s):  
Adrianna Kamińska ◽  
Iwona E Głowacka ◽  
Beata Pasternak ◽  
Rafał Głowacki ◽  
Grażyna Chwatko
Keyword(s):  
Acetic Acid ◽  
Lipoic Acid ◽  
Human Urine ◽  
Mobile Phase ◽  
Thiol Group ◽  
Bioanalytical Method ◽  
The Us ◽  
Us Fda ◽  
Reduced Forms

Aim: The first method on urinary excreted amounts of lipoyllysine (LLys) after lipoic acid (LA) supplementation was developed and validated. The suggested procedure allowed simultaneous determination of LLys and LA. Methodology & results: After the conversion of analytes into their reduced forms with tris(2-carboxyethyl)phosphine and derivatization via thiol group with 1-benzyl-2-chloropyridinium bromide, separation of analytes derivatives was performed on C18 column using a gradient mobile phase consisting of acetic acid and acetonitrile. The calibration curves for LA and LLys were linear (R2 > 0.999) in the range of 0.4–12 μM concentration and all validation results were acceptable, according to the US FDA bioanalytical method guidelines. Conclusion: This method was effectively applied for LA and LLys quantification in human urine after oral LA supplementation.

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