The three California cities of San Jose, Fresno, and West Los Angeles (wLA) were visited during March 2008 to collect on-road emission measurements of reactive nitrogen compounds from light-duty vehicles. At the San Jose and wLA sites, comparison with historical measurements showed that emissions of carbon monoxide (CO), hydrocarbons (HC), and nitric oxide (NO) continue to decrease in the on-road fleet, yet the ratio of nitrogen dioxide (NO(2)) to NO in new diesel vehicles appears to be undergoing large increases. A small fleet of 2007 diesel ambulances measured in Fresno was found to have more than 60% of their emitted oxides of nitrogen as NO(2). Ammonia (NH(3)) emissions are shown to have a strong dependence on model year and vehicle specific power. NH(3) means are 0.49 +/- 0.02, 0.49 +/- 0.01, and 0.79 +/- 0.02 g/kg of fuel for San Jose, Fresno, and wLA, respectively, with the larger emissions at the wLA site likely due to driving mode. NH(3) at these locations was found to account for 25%, 22%, and 27% of the molar fixed nitrogen emissions, respectively. Using these mean values to construct a national fuel-based NH(3) inventory results in a range of 210000 to 330000 short tons of NH(3) annually from light-duty vehicles.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/es903722p | DOI Listing |
Sci Total Environ
January 2025
Grupo de Ecología y Evolución de Vertebrados, Universidad de Antioquia, Colombia.
Environmental characteristics drastically shape the host-parasite associations under natural conditions. This is the case of parasites such as avian haemosporidians which naturally infect birds and are transmitted by insect vectors. Landscape characteristics are known to determine the epidemiology of transmission of these parasites in the wild, but the strength of these factors may differ at different spatial scales.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Protein Science, SciLifeLab, KTH Royal Institute of Technology, Stockholm, Sweden.
Accurate diagnosis and monitoring of neurodegenerative diseases require reliable biomarkers. Cerebrospinal fluid (CSF) proteins are promising candidates for reflecting brain pathology; however, their diagnostic utility may be compromised by natural variability between individuals, weakening their association with disease. Here, we measured the levels of 69 pre-selected proteins in cerebrospinal fluid using antibody-based suspension bead array technology in a multi-disease cohort of 499 individuals with neurodegenerative disorders including Alzheimer's disease (AD), behavioral variant frontotemporal dementia, primary progressive aphasias, amyotrophic lateral sclerosis (ALS), corticobasal syndrome, primary supranuclear palsy, along with healthy controls.
View Article and Find Full Text PDFUltrasound Obstet Gynecol
January 2025
Maternal Fetal Medicine Unit, Department of Obstetrics, Vall d'Hebron Barcelona Hospital Campus, Barcelona, Spain.
Objectives: To assess the performance of mean uterine artery pulsatility index (UtA-PI) at 18-22 and 24-28 weeks of gestation in the prediction of pre-eclampsia (PE) and small-for-gestational age (SGA), and its role in reassessing the risk of PE and SGA in pregnancies screened for PE in the first trimester.
Methods: This was a retrospective observational cohort study of 4464 women with singleton pregnancy screened routinely for PE in the first trimester, using the Gaussian algorithm, from March 2019 to May 2021, and who underwent UtA-PI assessment at 18-22 gestational weeks. Women were categorized as low risk or high risk based on the risk index obtained after first-trimester screening for PE.
Gac Sanit
December 2024
Grup de Recerca en Serveis Sanitaris, Vall d'Hebron Institut de Recerca, Hospital Universitari Vall d'Hebron, Barcelona, España; Sistemas de Información y Apoyo a la Decisión, Hospital Universitari Vall d'Hebron, Barcelona, España.
Visits to hospital emergency departments by patients with multimorbidity, complex chronic conditions, and frailty are becoming an increasing challenge. A territorial strategy has been developed, based on automated preselection lists, a nurse case manager with specialized experience, and a multi-level territorial referral consensus. The feasibility of this approach has been demonstrated, with 368 alerts detected, 85% of which were well-selected.
View Article and Find Full Text PDFBMC Med Ethics
November 2024
School of Health and Wellbeing, University of Glasgow, Glasgow, UK.
Background: Research in children is essential for them to benefit from the outcomes of research but involvement must be weighed against potential harms. In many countries and circumstances, medical research legally requires parental consent until the age of 18 years, with poorly defined recommendations for assent prior to this. However, there is little research exploring how these decisions are made by families and the ethical implications of this.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!