Impact of methanol intoxication on the human electrocardiogram

Background: Methanol is a common commercial compound that can lead to significant morbidity and mortality with high levels of exposure. The purpose of this study was to describe electrocardiographic (ECG) changes associated with methanol intoxication. Methods: A retrospective chart review was conducted with data from Kingston General Hospital collected between 2006 and 2011. Patient data, including demographics, medications, and laboratory data were recorded. Twelve-lead ECGs were obtained and changes were noted in relation to timing and extent of methanol intoxication. Results: Nine patients with a mean age of 45 years were analyzed. All patients ingested methanol orally and presented to hospital between < 1 to 25 h after ingestion. The mean plasma methanol concentration on admission was 49.8 mmol/L. A lower pH and higher plasma methanol concentration were associated with multiple ECG changes. On admission, ECG changes included sinus tachycardia (44%), PR prolongation (11%), QTc prolongation (22%) and non-specific T-wave changes (66%). One patient developed a type-1 Brugada ECG pattern. During their course in hospital, 7 patients required dialysis, 3 required mechanical ventilation, 3 developed visual impairment, and 1 died. All ECG changes normalized while in hospital. Conclusions: Methanol intoxication can lead to several ECG changes with sinus tachycardia and non-specific T-wave changes being the most common. These changes were more prominent in cases of severe acidosis

A continuous-flow gas chromatography 14C accelerator mass spectrometry system

Author Posting. © Arizona Board of Regents on behalf of the University of Arizona, 2010. This article is posted here by permission of Dept. of Geosciences, University of Arizona for personal use, not for redistribution. The definitive version was published in Radiocarbon 52 (2010): 295-300.Gas-accepting ion sources for radiocarbon accelerator mass spectrometry (AMS) have permitted the direct analysis of CO2 gas, eliminating the need to graphitize samples. As a result, a variety of analytical instruments can be interfaced to an AMS system, processing time is decreased, and smaller samples can be analyzed (albeit with lower precision). We have coupled a gas chromatograph to a compact 14C AMS system fitted with a microwave ion source for real-time compoundspecific 14C analysis. As an initial test of the system, we have analyzed a sample of fatty acid methyl esters and biodiesel. Peak shape and memory was better then existing systems fitted with a hybrid ion source while precision was comparable. 14C/12C ratios of individual components at natural abundance levels were consistent with those determined by conventional methods. Continuing refinements to the ion source are expected to improve the performance and scope of the instrument.This work was performed under NSF Cooperative Agreement Number OCE-0753487

New and improved demonstrations, each illustrating a single scientific paper

Thesis (Ed.M.)--Boston Universit

Rapid radiocarbon (14C) analysis of coral and carbonate samples using a continuous-flow accelerator mass spectrometry (CFAMS) system

Author Posting. © American Geophysical Union, 2011. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 26 (2011): PA4212, doi:10.1029/2011PA002174.Radiocarbon analyses of carbonate materials provide critical information for understanding the last glacial cycle, recent climate history and paleoceanography. Methods that reduce the time and cost of radiocarbon (14C) analysis are highly desirable for large sample sets and reconnaissance type studies. We have developed a method for rapid radiocarbon analysis of carbonates using a novel continuous-flow accelerator mass spectrometry (CFAMS) system. We analyzed a suite of deep-sea coral samples and compared the results with those obtained using a conventional AMS system. Measurement uncertainty is <0.02 Fm or 160 Ryr for a modern sample and the mean background was 37,800 Ryr. Radiocarbon values were repeatable and in good agreement with those from the conventional AMS system. Sample handling and preparation is relatively simple and the method offered a significant increase in speed and cost effectiveness. We applied the method to coral samples from the Eastern Pacific Ocean to obtain an age distribution and identify samples for further analysis. This paper is intended to update the paleoceanographic community on the status of this new method and demonstrate its feasibility as a choice for rapid and affordable radiocarbon analysis.This work was performed under NSF Cooperative Agreement OCE‐0753487, and also NSF‐OPP awards 0636787 and 0944474

A high-performance 14C accelerator mass spectrometry system

Author Posting. © Arizona Board of Regents on behalf of the University of Arizona, 2010. This article is posted here by permission of Dept. of Geosciences, University of Arizona for personal use, not for redistribution. The definitive version was published in Radiocarbon 52 (2010): 228-235.A new and unique radiocarbon accelerator mass spectrometry (AMS) facility has been constructed at the Woods Hole Oceanographic Institution. The defining characteristic of the new system is its large-gap optical elements that provide a larger-than-standard beam acceptance. Such a system is ideally suited for high-throughput, high-precision measurements of 14C. Details and performance of the new system are presented