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Full-Text Articles in Physical Sciences and Mathematics

The Waters Of Antarctica: Do They Belong To Some States, No States, Or All States?, Linda A. Malone Sep 2019

The Waters Of Antarctica: Do They Belong To Some States, No States, Or All States?, Linda A. Malone

Linda A. Malone

Major issues and complexities arise when one is looking at the international puzzle that is Antarctica. Despite being uninhabited year round and lacking substantial long-term international law rules for sovereignty, states still try to claim their sovereignty over various parts of Antarctica. The consortium of states under the Antarctica Treaty System (“ATS”) then further aggravates these complexities, especially when other states outside of the ATS have been arguing for different regimes and approaches to dealing with Antarctica and resource exploitation. Due to these major issues and a desperate need for a resolution in times of global climate change, this Article …


Responsibility To Protect, Libya To Japan, Linda A. Malone Sep 2019

Responsibility To Protect, Libya To Japan, Linda A. Malone

Linda A. Malone

No abstract provided.


Acknowledging The Impact Of Climate Change On National Security: A Long And Winding Road, Linda A. Malone Sep 2019

Acknowledging The Impact Of Climate Change On National Security: A Long And Winding Road, Linda A. Malone

Linda A. Malone

No abstract provided.


The Supreme Court’S Recent “Takings” Cases: The Koontz And Arkansas Decisions -- What Do They Mean For Local Government?, Lynda L. Butler Sep 2019

The Supreme Court’S Recent “Takings” Cases: The Koontz And Arkansas Decisions -- What Do They Mean For Local Government?, Lynda L. Butler

Lynda L. Butler

No abstract provided.


Book Review Of Eco-Pragmatism: Making Sensible Environmental Decisions In An Uncertain World, Lynda L. Butler Sep 2019

Book Review Of Eco-Pragmatism: Making Sensible Environmental Decisions In An Uncertain World, Lynda L. Butler

Lynda L. Butler

No abstract provided.


Coastal Marine Science For Law And Business Students: Preparing Law And Business Professionals To Make "Informed Decisions" About Coastal Issues, David H. Niebuhr, Lynda L. Butler, Don Rahtz, Britt E. Anderson, April N. Lawrence Sep 2019

Coastal Marine Science For Law And Business Students: Preparing Law And Business Professionals To Make "Informed Decisions" About Coastal Issues, David H. Niebuhr, Lynda L. Butler, Don Rahtz, Britt E. Anderson, April N. Lawrence

Lynda L. Butler

The rigors of employment-directed undergraduate education. and decreased emphasis on "Liberal Arts" studies occurring at some colleges and universities has left many graduates with a level of scientific understanding which is inadequate to make infonned choices about issues which effect the environment. To address this lack of scientific understanding. the Chesapeake Bay National Estuarine Research Reserve (Virginia) and the Virginia Institute of Marine Science, with the Marshall-Wythe School of Law and the School of Business Administration of the College of William and Mary are developing a Coastal Ecosystem Science Program to teach future law and business professionals the basics of …


Introduction/Welcome/Announcements, Kathryn Rowe, Davison M. Douglas, Elizabeth Armistead Andrews Sep 2019

Introduction/Welcome/Announcements, Kathryn Rowe, Davison M. Douglas, Elizabeth Armistead Andrews

Elizabeth Armistead Andrews

No abstract provided.


Initial Field Testing Results From Building-Integrated Solar Energy Harvesting Windows Installation In Perth, Australia, Mikhail Vasiliev, Mohammad Nur-E-Alam, Kamal Alameh Sep 2019

Initial Field Testing Results From Building-Integrated Solar Energy Harvesting Windows Installation In Perth, Australia, Mikhail Vasiliev, Mohammad Nur-E-Alam, Kamal Alameh

Mikhail Vasiliev

We report on the field testing datasets and performance evaluation results obtained
from a commercial property-based visually-clear solar window installation site in Perth-Australia.
This installation was fitted into a refurbished shopping center entrance porch and showcases the
potential of glass curtain wall-based solar energy harvesting in built environments. In particular,
we focus on photovoltaic (PV) performance characteristics such as the electric power output, specific
yield, day-to-day consistency of peak output power, and the amounts of energy generated and stored
daily. The dependencies of the generated electric power and stored energy on multiple environmental
and geometric parameters are also studied. An …


Closed-Form Probability Distribution Of Number Of Infections At A Given Time In A Stochastic Sis Epidemic Model.Pdf, Michael Otunuga Sep 2019

Closed-Form Probability Distribution Of Number Of Infections At A Given Time In A Stochastic Sis Epidemic Model.Pdf, Michael Otunuga

Olusegun Michael Otunuga

We study the effects of external fluctuations in the transmission rate of certain diseases and how these affect the distribution of the number of infected individuals over time. To do this, we introduce random noise in the transmission rate in a deterministic SIS model and study how the number of infections changes over time. The objective of this work is to derive and analyze the closed form probability distribution of the number of infections at a given time in the resulting stochastic SIS epidemic model. Using the Fokker-Planck equation, we reduce the differential equation governing the number of infections to …


Evolutionary History And Phylodynamics Of Influenza A And B Neuraminidase (Na) Genes Inferred From Large-Scale Sequence Analyses, Haizhen Zhong Sep 2019

Evolutionary History And Phylodynamics Of Influenza A And B Neuraminidase (Na) Genes Inferred From Large-Scale Sequence Analyses, Haizhen Zhong

Haizhen Zhong

Background: Influenza neuraminidase (NA) is an important surface glycoprotein and plays a vital role in viral replication and drug development. The NA is found in influenza A and B viruses, with nine subtypes classified in influenza A. The complete knowledge of influenza NA evolutionary history and phylodynamics, although critical for the prevention and control of influenza epidemics and pandemics, remains lacking.

Methodology/Principal findings: Evolutionary and phylogenetic analyses of influenza NA sequences using Maximum Likelihood and Bayesian MCMC methods demonstrated that the divergence of influenza viruses into types A and B occurred earlier than the divergence of influenza A …


Conformational Studies Of Glucose Transporter 1 (Glut1) As An Anticancer Drug Target, Suliman Almahmoud, Xiaofang Wang, Jonathan L. Vennerstrom, Haizhen A. Zhong Sep 2019

Conformational Studies Of Glucose Transporter 1 (Glut1) As An Anticancer Drug Target, Suliman Almahmoud, Xiaofang Wang, Jonathan L. Vennerstrom, Haizhen A. Zhong

Haizhen Zhong

Glucose transporter 1 (GLUT1) is a facilitative glucose transporter overexpressed in various types of tumors; thus, it has been considered as an important target for cancer therapy. GLUT1 works through conformational switching from an outward-open (OOP) to an inward-open (IOP) conformation passing through an occluded conformation. It is critical to determine which conformation is preferred by bound ligands because the success of structure-based drug design depends on the appropriate starting conformation of the target protein. To find out the most favorable GLUT 1 conformation for ligand binding, we ran systemic molecular docking studies for different conformations of GLUT1 using known …


Design, Synthesis And Biological Evaluation Of Novel Hedgehog Inhibitors For Treating Pancreatic Cancer, Vinod Kumar, Amit Kumar Chaudhary, Yuxiang Dong, Haizhen Zhong, Goutam Mondal, Feng Lin, Virender Kumar, Ram I. Mahato Sep 2019

Design, Synthesis And Biological Evaluation Of Novel Hedgehog Inhibitors For Treating Pancreatic Cancer, Vinod Kumar, Amit Kumar Chaudhary, Yuxiang Dong, Haizhen Zhong, Goutam Mondal, Feng Lin, Virender Kumar, Ram I. Mahato

Haizhen Zhong

Hedgehog (Hh) pathway is involved in epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) maintenance resulting in tumor progression. GDC-0449, an inhibitor of Hh pathway component smoothened (Smo) has shown promise in the treatment of various cancers including pancreatic cancer. However, the emergence of resistance during GDC-0449 treatment with numerous side effects limits its use. Therefore, here we report the design, synthesis and evaluation of novel GDC-0449 analogs using N-[3-(2-pyridinyl) phenyl] benzamide scaffold. Cell-based screening followed by molecular simulation revealed 2-chloro-N1-[4-chloro-3-(2-pyridinyl)phenyl]-N4,N4-bis(2-pyridinylmethyl)-1,4- benzenedicarboxamide (MDB5) as most potent analog, binding with an extra interactions in seventransmembrane (7-TM) domain of Smo due to …


Animal Research, Accountability, Openness And Public Engagement: Report From An International Expert Forum, Elisabeth H. Ormandy, Daniel M. Weary, Katarina Cvek, Mark Fisher, Kathrin Herrmann, Pru Hobson-West, Michael Mcdonald, William Milsom, Margaret Rose, Andrew Rowan, Joanne Zurlo, Marina A.G. Von Keyserlingk Sep 2019

Animal Research, Accountability, Openness And Public Engagement: Report From An International Expert Forum, Elisabeth H. Ormandy, Daniel M. Weary, Katarina Cvek, Mark Fisher, Kathrin Herrmann, Pru Hobson-West, Michael Mcdonald, William Milsom, Margaret Rose, Andrew Rowan, Joanne Zurlo, Marina A.G. Von Keyserlingk

Andrew N. Rowan, DPhil

In November 2013, a group of international experts in animal research policy (n = 11) gathered in Vancouver, Canada, to discuss openness and accountability in animal research. The primary objective was to bring together participants from various jurisdictions (United States, Sweden, Australia, New Zealand, Germany, Canada and the United Kingdom) to share practices regarding the governance of animals used in research, testing and education, with emphasis on the governance process followed, the methods of community engagement, and the balance of openness versus confidentiality. During the forum, participants came to a broad consensus on the need for: (a) evidence-based metrics to …


The Laws Of Complexity & The Complexity Of Laws: The Implications Of Computational Complexity Theory For The Law, Eric Kades Sep 2019

The Laws Of Complexity & The Complexity Of Laws: The Implications Of Computational Complexity Theory For The Law, Eric Kades

Eric A. Kades

No abstract provided.


Reverse Mathematics Of Matroids, Jeffry L. Hirst, Carl Mummert Sep 2019

Reverse Mathematics Of Matroids, Jeffry L. Hirst, Carl Mummert

Carl Mummert

Matroids generalize the familiar notion of linear dependence from linear algebra. Following a brief discussion of founding work in computability and matroids, we use the techniques of reverse mathematics to determine the logical strength of some basis theorems for matroids and enumerated matroids. Next, using Weihrauch reducibility, we relate the basis results to combinatorial choice principles and statements about vector spaces. Finally, we formalize some of the Weihrauch reductions to extract related reverse mathematics results. In particular, we show that the existence of bases for vector spaces of bounded dimension is equivalent to the induction scheme for \Sigma^0_2 formulas.


Thermo-Mechanical Response Of Self-Assembled Nanoparticle Membranes, Yifan Wang, Henry Chan, Badri Narayanan, Sean P. Mcbride, Subramanian K.R.S. Sankaranarayanan, Xiao-Min Lin, Heinrich M. Jaeger Sep 2019

Thermo-Mechanical Response Of Self-Assembled Nanoparticle Membranes, Yifan Wang, Henry Chan, Badri Narayanan, Sean P. Mcbride, Subramanian K.R.S. Sankaranarayanan, Xiao-Min Lin, Heinrich M. Jaeger

Dr. Sean P. McBride

Ultrathin membranes composed of metallic or semiconducting nanoparticles capped with short ligand molecules are hybrid materials that have attracted considerable research interest.1-12 In contrast to two-dimensional (2D) membranes such as graphene and transition metal dichalcogenides monolayers, nanoparticle membranes can be engineered to achieve widely tunable mechanical, electronic or optical properties through different combinations of inorganic cores and organic ligands. In terms of mechanical properties, these membranes can form large area (tens of microns in diameter) freestanding structures with high Young’s moduli (~GPa) and fracture strength.1,13-15 Molecular dynamics (MD) simulations have indicated how this mechanical robustness can arise from …


Transmission And Guiding Of Fast Electrons Through Insulating Nanocapillaries And Comparison With Ion Guiding, Susanta Das Sep 2019

Transmission And Guiding Of Fast Electrons Through Insulating Nanocapillaries And Comparison With Ion Guiding, Susanta Das

Susanta Das

Transmission and guiding of fast electrons (500 and 1000 eV) through an insulating polyethylene terephthalate nanocapillary foil has been investigated and compared with results for slow highly charged ions. As for slow ions, guiding is attributed to charge-up of the inner walls near the capillary entrance, which, after a characteristic time, electrostatically deflects the traversing ions causing them to be guided through the sample along the capillary axis. The measurements were performed at WMU. Electron guiding is found to decrease faster with both energy and foil tilt angle than for ions. Ions lose negligible energy during the course of guiding, …


Measuring Circuit Splits: A Cautionary Note, Aaron-Andrew P. Bruhl Sep 2019

Measuring Circuit Splits: A Cautionary Note, Aaron-Andrew P. Bruhl

Aaron-Andrew P. Bruhl

A number of researchers have recently published new measures of the Supreme Court’s behavior in resolving conflicts in the lower courts. These new measures represent an improvement over prior, cruder approaches, but it turns out that measuring the Court’s resolutions of conflicts is surprisingly difficult. The aim of this methodological comment is to describe those difficulties and to establish several conclusions that follow from them. First, the new measures of the Court’s behavior are certainly imprecise and may reflect biased samples. Second, using the Supreme Court Database, which some studies rely on to assemble a dataset of cases resolving conflicts, …


Integrating Multiple Modalities Into Deep Learning Network, Patrick Mcneil Sep 2019

Integrating Multiple Modalities Into Deep Learning Network, Patrick Mcneil

Patrick McNeil

Deep learning networks in the literature traditionally only used a single input modality (or data stream). Integrating multiple modalities into deep learning networks with the goal of correlating extracted features was a major issue. Traditional methods involved treating each modality separately and then writing custom code to combine the extracted features. Current solutions for small numbers of modalities (three or less) showed there are multiple architectures for modality integration. With an increase in the number of modalities, the “curse of dimensionality” affects the performance of the system. The research showed current methods for larger scale integrations required separate, custom created …


Acid And Base Stress And Transcriptomic Responses In Bacillus Subtilis., Brian Jones, Jessica C. Wilks, Ryan D. Kitko, Sarah H. Cleeton, Grace E. Lee, Chinagozi S. Ugwu, Sandra S. Bondurant, Joan L. Slonczewski Sep 2019

Acid And Base Stress And Transcriptomic Responses In Bacillus Subtilis., Brian Jones, Jessica C. Wilks, Ryan D. Kitko, Sarah H. Cleeton, Grace E. Lee, Chinagozi S. Ugwu, Sandra S. Bondurant, Joan L. Slonczewski

Brian Jones

Acid and base environmental stress responses were investigated in Bacillus subtilis. B. subtilis AG174 cultures in buffered potassium-modified Luria broth were switched from pH 8.5 to pH 6.0 and recovered growth rapidly, whereas cultures switched from pH 6.0 to pH 8.5 showed a long lag time. Log-phase cultures at pH 6.0 survived 60 to 100% at pH 4.5, whereas cells grown at pH 7.0 survived <15%. Cells grown at pH 9.0 survived 40 to 100% at pH 10, whereas cells grown at pH 7.0 survived <5%. Thus, growth in a moderate acid or base induced adaptation to a more extreme acid or base, respectively. Expression indices from Affymetrix chip hybridization were obtained for 4,095 protein-encoding open reading frames of B. subtilis grown at external pH 6, pH 7, and pH 9. Growth at pH 6 upregulated acetoin production (alsDS), dehydrogenases (adhA, ald, fdhD, and gabD), and decarboxylases (psd and speA). Acid upregulated malate metabolism (maeN), metal export (czcDO and cadA), oxidative stress (catalase katA; OYE family namA), and the SigX extracytoplasmic stress regulon. Growth at pH 9 upregulated arginine catabolism (roc), which generates organic acids, glutamate synthase (gltAB), polyamine acetylation and transport (blt), the K(+)/H(+) antiporter (yhaTU), and cytochrome oxidoreductases (cyd, ctaACE, and qcrC). The SigH, SigL, and SigW regulons were upregulated at high pH. Overall, greater genetic adaptation was seen at pH 9 than at pH 6, which may explain the lag time required for growth shift to high pH. Low external pH favored dehydrogenases and decarboxylases that may consume acids and generate basic amines, whereas high external pH favored catabolism-generating acids.


Predicting Economic Optimal Nitrogen Rate With The Anaerobic Potentially Mineralizable Nitrogen Test, Jason D. Clark, Fabián G. Fernández, Kristen S. Veum, James J. Camberato, Paul R. Carter, Richard B. Ferguson, David W. Franzen, Daniel E. Kaiser, Newell R. Kitchen, Carrie A. M. Laboski, Emerson D. Nafziger, Carl J. Rosen, John E. Sawyer, John F. Shanahan Sep 2019

Predicting Economic Optimal Nitrogen Rate With The Anaerobic Potentially Mineralizable Nitrogen Test, Jason D. Clark, Fabián G. Fernández, Kristen S. Veum, James J. Camberato, Paul R. Carter, Richard B. Ferguson, David W. Franzen, Daniel E. Kaiser, Newell R. Kitchen, Carrie A. M. Laboski, Emerson D. Nafziger, Carl J. Rosen, John E. Sawyer, John F. Shanahan

John E. Sawyer

Estimates of mineralizable N with the anaerobic potentially mineralizable N (PMNan) test could improve predictions of corn (Zea mays L.) economic optimal N rate (EONR). A study across eight US midwestern states was conducted to quantify the predictability of EONR for single and split N applications by PMNan. Treatment factors included different soil sample timings (pre-plant and V5 development stage), planting N rates (0 and 180 kg N ha−1), and incubation lengths (7, 14, and 28 d) with and without initial soil NH4–N included with PMNan. Soil was sampled …


United States Midwest Soil And Weather Conditions Influence Anaerobic Potentially Mineralizable Nitrogen, Jason D. Clark, Kristen S. Veum, Fabián G. Fernández, James J. Camberato, Paul R. Carter, Richard B. Ferguson, David W. Franzen, Daniel E. Kaiser, Newell R. Kitchen, Carrie A. M. Laboski, Emerson D. Nafziger, Carl J. Rosen, John E. Sawyer, John F. Shanahan Sep 2019

United States Midwest Soil And Weather Conditions Influence Anaerobic Potentially Mineralizable Nitrogen, Jason D. Clark, Kristen S. Veum, Fabián G. Fernández, James J. Camberato, Paul R. Carter, Richard B. Ferguson, David W. Franzen, Daniel E. Kaiser, Newell R. Kitchen, Carrie A. M. Laboski, Emerson D. Nafziger, Carl J. Rosen, John E. Sawyer, John F. Shanahan

John E. Sawyer

Nitrogen provided to crops through mineralization is an important factor in N management guidelines. Understanding of the interactive effects of soil and weather conditions on N mineralization needs to be improved. Relationships between anaerobic potentially mineralizable N (PMNan) and soil and weather conditions were evaluated under the contrasting climates of eight US Midwestern states. Soil was sampled (0–30 cm) for PMNan analysis before pre-plant N application (PP0N) and at the V5 development stage from the pre-plant 0 (V50N) and 180 kg N ha−1 (V5180N) rates and incubated for 7, 14, …


Reverse Mathematics And Uniformity In Proofs Without Excluded Middle, Jeffry L. Hirst, Carl Mummert Sep 2019

Reverse Mathematics And Uniformity In Proofs Without Excluded Middle, Jeffry L. Hirst, Carl Mummert

Carl Mummert

We show that when certain statements are provable in subsystems of constructive analysis using intuitionistic predicate calculus, related sequential statements are provable in weak classical subsystems. In particular, if a \Pi^1_2 sentence of a certain form is provable using E-HAω along with the axiom of choice and an independence of premise principle, the sequential form of the statement is provable in the classical system RCA. We obtain this and similar results using applications of modified realizability and the Dialectica interpretation. These results allow us to use techniques of classical reverse mathematics to demonstrate the unprovability of several mathematical principles …


Reverse Mathematics And Properties Of Finite Character, Damir D. Dzhafarov, Carl Mummert Sep 2019

Reverse Mathematics And Properties Of Finite Character, Damir D. Dzhafarov, Carl Mummert

Carl Mummert

We study the reverse mathematics of the principle stating that,for every property of finite character, every set has a maximal subset satisfying the property. In the context of set theory, this variant of Tukey’s lemma is equivalent to the axiom of choice. We study its behavior in the context of second-order arithmetic, where it applies to sets of natural numbers only, and give a full characterization of its strength in terms of the quantifier structure of the formula defining the property. We then study the interaction between properties of finite character and finitary closure operators, and the interaction between these …


Order Statistics On The Spacings Between Order Statistics, Iosif Pinelis Sep 2019

Order Statistics On The Spacings Between Order Statistics, Iosif Pinelis

Iosif Pinelis

No abstract provided.


The Analysis Of Protein-Bound Thiocyanate In Plasma Of Smokers And Non-Smokers As A Marker Of Cyanide Exposure, Stephanie L. Youso, Gary A. Rockwood, Brian A. Logue Sep 2019

The Analysis Of Protein-Bound Thiocyanate In Plasma Of Smokers And Non-Smokers As A Marker Of Cyanide Exposure, Stephanie L. Youso, Gary A. Rockwood, Brian A. Logue

Brian Logue

When cyanide is introduced into the body, it quickly transforms through a variety of chemical reactions, normally involving sulfur donors, to form more stable chemical species. Depending on the nature of the sulfur donor, cyanide may be transformed into free thiocyanate, the major metabolite of cyanide transformation, 2-amino-2-thiazoline-4-carboxylic acid or protein-bound thiocyanate (PB-SCN) adducts. Because protein adducts are generally stable in biological systems, it has been suggested that PB-SCN may have distinct advantages as a marker of cyanide exposure. In this study, plasma was analyzed from 25 smokers (chronic low-level cyanide exposure group) and 25 non-smokers for PB-SCN. The amount …


The Analysis Of Cyanide And Its Breakdown Products In Biological Samples, Brian A. Logue, Diane M. Hinkens, Steven I. Baskin, Gary A. Rockwood Sep 2019

The Analysis Of Cyanide And Its Breakdown Products In Biological Samples, Brian A. Logue, Diane M. Hinkens, Steven I. Baskin, Gary A. Rockwood

Brian Logue

Cyanide is a toxic chemical that may be introduced into living organisms as a result of natural processes and/or anthropogenic uses (legal or illicit). Exposure to cyanide can be verified by analysis of cyanide or one of its breakdown products from biological samples. This verification may be important for medical, law-enforcement, military, forensic, research, or veterinary purposes. This review will discuss current bioanalytical techniques used for the verification of cyanide exposure, identify common problems associated with the analysis of cyanide and its biological breakdown products, and briefly address the metabolism and toxicokinetics of cyanide and its breakdown products in biological …


Simultaneous High-Performance Liquid Chromatography-Tandem Mass Spectrometry (Hplc-Ms-Ms) Analysis Of Cyanide And Thiocyanate From Swine Plasma, Raj K. Bhandari, Erica Manandhar, Robert P. Oda, Gary A. Rockwood, Brian A. Logue Sep 2019

Simultaneous High-Performance Liquid Chromatography-Tandem Mass Spectrometry (Hplc-Ms-Ms) Analysis Of Cyanide And Thiocyanate From Swine Plasma, Raj K. Bhandari, Erica Manandhar, Robert P. Oda, Gary A. Rockwood, Brian A. Logue

Brian Logue

An analytical procedure for the simultaneous determination of cyanide and thiocyanate in swine plasma was developed and validated. Cyanide and thiocyanate were simultaneously analyzed by high-performance liquid chromatography tandem mass spectrometry in negative ionization mode after rapid and simple sample preparation. Isotopically labeled internal standards, Na13C15N and NaS13C15N, were mixed with swine plasma (spiked and nonspiked), proteins were precipitated with acetone, the samples were centrifuged, and the supernatant was removed and dried. The dried samples were reconstituted in 10 mM ammonium formate. Cyanide was reacted with naphthalene-2,3-dicarboxaldehyde and taurine to form N-substituted …


The Analysis Of 2-Amino-2-Thiazoline-4-Carboxylic Acid In The Plasma Of Smokers And Non-Smokers, Brian A. Logue, Wendy K. Maserek, Gary A. Rockwood, Michael W. Keebaugh, Steven I. Baskin Sep 2019

The Analysis Of 2-Amino-2-Thiazoline-4-Carboxylic Acid In The Plasma Of Smokers And Non-Smokers, Brian A. Logue, Wendy K. Maserek, Gary A. Rockwood, Michael W. Keebaugh, Steven I. Baskin

Brian Logue

ATCA (2-amino-2-thiazoline-4-carboxylic acid) is a promising marker to assess cyanide exposure because of several advantages of ATCA analysis over direct determination of cyanide and alternative cyanide biomarkers (i.e. stability in biological matrices, consistent recovery, and relatively small endogenous concentrations). Concentrations of ATCA in the plasma of smoking and non-smoking human volunteers were analyzed using gaschromatography mass-spectrometry to establish the feasibility of using ATCA as a marker for cyanide exposure. The levels of ATCA in plasma of smoking volunteers, 17.2 ng/ml, were found to be significantly (p < 0.001) higher than that of non-smoking volunteers, 11.8 ng/ml. Comparison of ATCA concentrations of smokers relative to nonsmokers in both urine and plasma yielded relatively similar results. The concentration ratio of ATCA for smokers versus non-smokers in plasma and urine was compared to similar literature studies of cyanide and thiocyanate, and correlations are discussed. This study supports previous evidence that ATCA can be used to determine past cyanide exposure and indicates that further studies should be pursued to validate the use of ATCA as a marker of cyanide exposure.


Organ-Distribution Of The Metabolite 2-Aminothiazoline-4-Carboxylic Acid In A Rat Model Following Cyanide Exposure, Ilona Petrikovics, David E. Thompson, Gary A. Rockwood, Brian A. Logue Sep 2019

Organ-Distribution Of The Metabolite 2-Aminothiazoline-4-Carboxylic Acid In A Rat Model Following Cyanide Exposure, Ilona Petrikovics, David E. Thompson, Gary A. Rockwood, Brian A. Logue

Brian Logue

The reaction of cyanide (CN) with cystine to produce 2-aminothiazoline-4-carboxylic acid (ATCA) is one of the independent detoxification pathways of cyanide in biological systems. In this report, in vivo production of ATCA and its distributions in plasma and organs were studied after a subcutaneous sublethal dose of 4 mg/kg body weight potassium cyanide (KCN) administration to rats. At this sublethal dose of KCN, ATCA concentration was not significantly increased in the plasma samples, however, it was found significantly increased in liver samples. These results suggested that ATCA might not be a good diagnostic biomarker in plasma for sublethal …