Normal men have been found to develop pruritus and gas bubble lesions in the skin, and disruption of vestibular function, when breathing nitrogen or neon with oxygen while surrounded by helium at increased ambient pressure. This phenomenon, which occurs at stable ambient pressures, at 1 or many ATA, has been designated the "isobaric gas counterdiffusion syndrome." In a series of analyses and experiments in vivo and in vitro the cause of the syndrome has been established as due to gas accumulation and development of gas bubbles in tissues as a result of differences in selective diffusivities, for various respired and ambient gases, in the tissue substances between capillary blood and the surrounding atmosphere. The phenomenon here described in man is an initial stage of a process shown later in animals to progress to continuous, massive, lethal, intravascular gas embolization.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1152/jappl.1975.39.3.434 | DOI Listing |
Talanta
April 2025
State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan, 430074, China. Electronic address:
Accurate in situ carbon isotopic measurements of magnesium-rich carbonates using LA-MC-ICP-MS require effective correction for isobaric interference, particularly from doubly charged Mg ions that can induce δC deviations of several permil. This study focuses on optimizing gas parameters and developing robust correction strategies to improve the accuracy of δC measurements. Experimental results demonstrate that the introduction of nitrogen gas at a flow rate of 4-6 mL/min effectively doubles signal sensitivity while optimizing low helium (0.
View Article and Find Full Text PDFAnal Chem
December 2024
MOBILion Systems, Inc., 4 Hillman Drive, Suite 130, Chadds Ford, Pennsylvania 19317, United States.
Various rounded turn designs in Structures for Lossless Ion Manipulation (SLIM) were explored via ion trajectory simulations. The optimized design was integrated into a SLIM ion mobility (IM) system coupled with a time-of-flight (TOF) mass spectrometer (MS) for further experimental investigation. The SLIM-TOF IM-MS system was assessed for IM resolution and ion transmission efficiency across a wide / range using various RF frequencies and buffer gas combinations.
View Article and Find Full Text PDFAnal Chem
November 2024
Biological Sciences Division, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99354, United States.
The ability to uniquely identify a compound requires highly precise and orthogonal measurements. Here we describe a newly developed analytical platform that integrates high resolution ion mobility and cryogenic vibrational ion spectroscopy for high-precision structural characterizations. This platform allows for the temporal separation of isomeric/isobaric ions and provides a highly sensitive description of the ion's adopted geometry in the gas phase.
View Article and Find Full Text PDFJ Anim Sci
January 2024
Department of Animal Science, Iowa State University, Ames, IA 50011, USA.
J Am Soc Mass Spectrom
December 2024
Joint Mass Spectrometry Centre (JMSC)/Chair of Analytical Chemistry, University of Rostock, 18059 Rostock, Germany.
We introduce vacuum resonance-enhanced multiphoton ionization (REMPI) with high-resolution Orbitrap Fourier transform mass spectrometry (FTMS) for analyzing silylated polar compounds. UV laser radiation at 248 nm sensitively and selectively targets aromatic constituents, while high-resolution mass spectrometry (HRMS) enables high-performance mass spectrometric detection. This workflow enhances the detection confidence of polar constituents by identifying unique isotopologue patterns, including at the isotopic fine structure (IFS) level, in analytical standards and complex bio-oils.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!