Linearity and detection thresholds of atmospheric pressure ionization-mass spectrometry (API-MS) were determined for 11 aroma compounds in air at concentrations ranging from 50 ppb to approximately 450 ppm (moles of volatile per mole of air). In most cases, the protonated molecular ion (i.e., m/z = M + 1) was the base peak throughout the range; however, some compounds showed an increase in fragmentation at lower concentrations. Detection limits varied greatly (from 50 ppb to 14 ppm) depending upon the aroma compound being measured. The linear range was also strongly dependent upon the aroma compound, with values ranging from <10-fold change in concentration to >4000-fold change in concentration depending upon the volatile being studied. The two volatiles with poor detection thresholds also exhibited the smallest linear range. Most compounds had linear ranges of >200. There was no apparent relationship between gas-phase basicity and either detection limit or linear range.
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http://dx.doi.org/10.1021/jf0486545 | DOI Listing |
J Adolesc Health
January 2025
Social and Behavioral Sciences, School of Public Health, West Virginia University, Morgantown, West Virginia.
Purpose: Recent research suggests that caffeine use may promote a range of adjustment difficulties among adolescents, particularly during the middle school years. The effects of caffeine are particularly concerning given the increased use of high-dosage caffeine products, such as energy drinks, among youth. We investigated the influence of caffeine use on trajectories of conduct problems among early adolescents.
View Article and Find Full Text PDFJ Neuroeng Rehabil
January 2025
Department of BioMechanical Engineering, Delft University of Technology, Mekelweg 2, Delft, 2628 CD, South-Holland, The Netherlands.
Duchenne Muscular Dystrophy (DMD) progressively leads to loss of limb function due to muscle weakness. The incurable nature of the disease shifts the focus to improving quality of life, including assistive supports to improve arm function. Over time, the passive joint impedance (Jimp) of people with DMD increases.
View Article and Find Full Text PDFClin Epigenetics
January 2025
Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, UK.
Alcohol consumption is an important risk factor for multiple diseases. It is typically assessed via self-report, which is open to measurement error through recall bias. Instead, molecular data such as blood-based DNA methylation (DNAm) could be used to derive a more objective measure of alcohol consumption by incorporating information from cytosine-phosphate-guanine (CpG) sites known to be linked to the trait.
View Article and Find Full Text PDFBMC Endocr Disord
January 2025
Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, 325000, China.
Background: The Weight-adjusted-waist index (WWI) has emerged as a predictive factor for a range of metabolic disorders. To date, the predictive value of the WWI in relation to sarcopenia in individuals with diabetics has not been extensively explored. This study aims to investigate the impact of the WWI on the prevalence of sarcopenia among patients with type 2 diabetes mellitus (T2DM).
View Article and Find Full Text PDFSci Rep
January 2025
Department of Electrical Power, Adama Science and Technology University, Adama, 1888, Ethiopia.
Although the Transformer architecture has established itself as the industry standard for jobs involving natural language processing, it still has few uses in computer vision. In vision, attention is used in conjunction with convolutional networks or to replace individual convolutional network elements while preserving the overall network design. Differences between the two domains, such as significant variations in the scale of visual things and the higher granularity of pixels in images compared to words in the text, make it difficult to transfer Transformer from language to vision.
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