We developed an analytical method and constrained procedural boundary conditions that enable accurate and precise Zn isotope ratio measurements in urban aerosols. We also demonstrate the potential of this new isotope system for air pollutant source tracing. The procedural blank is around 5 ng and significantly lower than published methods due to a tailored ion chromatographic separation. Accurate mass bias correction using external correction with Cu is limited to Zn sample content of approximately 50 ng due to the combined effect of blank contribution of Cu and Zn from the ion exchange procedure and the need to maintain a Cu/Zn ratio of approximately 1. Mass bias is corrected for by applying the common analyte internal standardization method approach. Comparison with other mass bias correction methods demonstrates the accuracy of the method. The average precision of delta(66)Zn determinations in aerosols is around 0.05 per thousand per atomic mass unit. The method was tested on aerosols collected in Sao Paulo City, Brazil. The measurements reveal significant variations in delta(66)Zn(Imperial) ranging between -0.96 and -0.37 per thousand in coarse and between -1.04 and 0.02 per thousand in fine particular matter. This variability suggests that Zn isotopic compositions distinguish atmospheric sources. The isotopic light signature suggests traffic as the main source. We present further delta(66)Zn(Imperial) data for the standard reference material NIST SRM 2783 (delta(66)Zn(Imperial) = 0.26 +/- 0.10 per thousand).
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http://dx.doi.org/10.1021/ac8019587 | DOI Listing |
Lipids Health Dis
January 2025
Department of Pediatrics, West China Second University Hospital, Sichuan University, No. 20, Section 3, South Renmin Road, Chengdu, Sichuan Province, 610041, China.
Background: This study aimed to investigate the association between relative fat mass (RFM) and asthma, as well as to explore the mediating role of Systemic Immune-Inflammation Index (SII) and Systemic Inflammation Response Index (SIRI).
Methods: This cross-sectional study utilized data from the National Health and Nutrition Examination Survey from 2007 to 2018. Associations between RFM and asthma were tested using multivariable logistic regressions, restricted cubic splines, subgroup analyses, and interaction tests, with mediation analysis for SII and SIRI.
BMJ Open
December 2024
Department of Pediatrics, Khon Kaen University Faculty of Medicine, Khon Kaen, Thailand.
Objective: Infants are at a high risk of developing anaemia, which can arise from various causes, including inappropriate feeding practices. However, few infants attend anaemia screening programmes due to poor cooperation and being time-consuming. This study evaluated the accuracy of noninvasive total haemoglobin (Hb) spot-check monitoring as part of anaemia screening in healthy infants, compared with the conventional laboratory method.
View Article and Find Full Text PDFBMJ Open
December 2024
School of Nutrition, Federal University of Bahia, Salvador, Brazil.
J Affect Disord
January 2025
Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China. Electronic address:
Background: Depression and cognitive impairments are prevalent among older adults, with evidence suggesting potential links to obesity and lipid metabolism disturbances. This study investigates the relationships between the triglyceride-glucose (TyG) index, body mass index (BMI), depression, and cognitive dysfunction in older adults, leveraging data from the NHANES survey and employing machine learning techniques.
Methods: We analysed 1352 participants aged 60-79 from the 2011-2014 NHANES dataset, who underwent cognitive function testing, depression assessments, and TyG index measurements.
Invest Ophthalmol Vis Sci
January 2025
School of Psychology and Public Health, La Trobe University, Melbourne, Australia.
Purpose: Prolonged exposure to broadband light with a short-wavelength (blue) or long-wavelength (orange/red) bias is known to impact eye growth and refraction, but the mechanisms underlying this response are unknown. Thus, the present study investigated the effects of broadband blue and orange lights with well-differentiated spectrums on refractive development and global flash electroretinography (gfERG) measures of retinal function in the chick myopia model.
Methods: Chicks were raised for 4 days with monocular negative lenses, or no lens, under blue, orange, or white light.
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