Publications by authors named "Jorba O"

Ground-level ozone (O) is a harmful air pollutant formed in the atmosphere by the interaction between sunlight and precursor gases. Exposure to current O levels in Europe is a major source of premature mortality from air pollution. However, mitigation actions have been mainly designed and implemented at the national and regional scales, lacking a comprehensive assessment of the geographic sources of O pollution and its associated health impacts.

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Understanding the atmospheric processes involving carbonaceous aerosols (CAs) is crucial for assessing air pollution impacts on human health and climate. The sources and formation mechanisms of CAs are not well understood, making it challenging to quantify impacts in models. Studies suggest residential wood combustion (RWC) and traffic significantly contribute to CAs in Europe's urban and rural areas.

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Tropospheric ozone (O) is a secondary air pollutant that affects human health, vegetation and climate, especially in Mediterranean countries such as Spain. In order to tackle this long-standing issue, the Spanish government recently started to design the Spanish O Mitigation Plan. To support this initiative and ultimately provide recommendations, we performed a first ambitious emission and air quality modeling exercise.

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Ozone (O) pollution is a persistent problem in many regions of Spain, so understanding O precursor emissions and trends is essential to design effective control strategies. We estimated the impact of Non-Methane Volatile Organic Compounds (NMVOC) species upon O formation potential (OFP) using the maximum incremental reactivity approach. For this, we developed a speciated NMVOC emission inventory for Spain from 2010 to 2019 combining national reported emissions with state-of-the-art speciation profiles, which resulted in a database of emissions for over 900 individual NMVOC species and 153 individual sectors.

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Previous studies have reported a decrease in air pollution levels following the enforcement of lockdown measures during the first wave of the COVID-19 pandemic. However, these investigations were mostly based on simple pre-post comparisons using past years as a reference and did not assess the role of different policy interventions. This study contributes to knowledge by quantifying the association between specific lockdown measures and the decrease in NO, O, PM, and PM levels across 47 European cities.

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Barcelona city (Spain) is applying a series of traffic restriction measures that aim at renewing and reducing the amount of circulating vehicles to improve air quality. The measures include changes in the built environment to reduce private vehicle space in specific areas through the so-called "superblocks" and tactical urban planning actions, along with the implementation of a city-wide Low Emission Zone (LEZ) that restricts the entry of the most polluting vehicles to the city. Our study quantifies the impact of these measures in the greater area of Barcelona combining a coupled macroscopic traffic and pollutant emission model with a multi-scale air quality model.

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We offer an overview of the COVID-19 -driven air quality changes across 11 metropolises in Spain with the focus on lessons learned on how continuing abating pollution. Traffic flow decreased by up to 80% during the lockdown and remained relatively low during the full relaxation (June and July). After the lockdown a significant shift from public transport to private vehicles (+21% in Barcelona) persisted due to the pervasive fear that using public transport might increase the risk of SARS-CoV-2 infection, which need to be reverted as soon as possible.

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Background And Objective: The relationship between IPF development and environmental factors has not been completely elucidated. Analysing geographic regions of idiopathic pulmonary fibrosis (IPF) cases could help identify those areas with higher aggregation and investigate potential triggers. We hypothesize that cross-analysing location of IPF cases and areas of consistently high air pollution concentration could lead to recognition of environmental risk factors for IPF development.

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Since the first International Cooperative for Aerosol Prediction (ICAP) multi-model ensemble (MME) study, the number of ICAP global operational aerosol models has increased from five to nine. An update of the current ICAP status is provided, along with an evaluation of the performance of ICAP-MME over 2012-2017, with a focus on June 2016-May 2017. Evaluated with ground-based Aerosol Robotic Network (AERONET) aerosol optical depth (AOD) and data assimilation quality MODerate-resolution Imaging Spectroradiometer (MODIS) retrieval products, the ICAP-MME AOD consensus remains the overall top-scoring and most consistent performer among all models in terms of root-mean-square error (RMSE), bias and correlation for total, fine- and coarse-mode AODs as well as dust AOD; this is similar to the first ICAP-MME study.

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It is well established that in Europe, high O concentrations are most pronounced in southern/Mediterranean countries due to the more favourable climatological conditions for its formation. However, the contribution of the different sources of precursors to O formation within each country relative to the imported (regional and hemispheric) O is poorly quantified. This lack of quantitative knowledge prevents local authorities from effectively designing plans that reduce the exceedances of the O target value set by the European air quality directive.

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The evaluation and intercomparison of air quality models is key to reducing model errors and uncertainty. The projects AQMEII3 and EURODELTA-Trends, in the framework of the Task Force on Hemispheric Transport of Air Pollutants and the Task Force on Measurements and Modelling, respectively (both task forces under the UNECE Convention on the Long Range Transport of Air Pollution, LTRAP), have brought together various regional air quality models to analyze their performance in terms of air concentrations and wet deposition, as well as to address other specific objectives. This paper jointly examines the results from both project communities by intercomparing and evaluating the deposition estimates of reduced and oxidized nitrogen (N) and sulfur (S) in Europe simulated by 14 air quality model systems for the year 2010.

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The CALIOPE air quality modelling system has been used to diagnose ground level O(3) concentration for the year 2004, over the Iberian Peninsula. We investigate the improvement in the simulation of daily O(3) maximum by the use of a post-processing such as the Kalman filter bias-adjustment technique. The Kalman filter bias-adjustment technique is a recursive algorithm to optimally estimate bias-adjustment terms from previous measurements and model results.

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The CALIOPE project, funded by the Spanish Ministry of the Environment, aims at establishing an air quality forecasting system for Spain. With this goal, CALIOPE modeling system was developed and applied with high resolution (4km×4km, 1h) using the HERMES emission model (including emissions of resuspended particles from paved roads) specifically built up for Spain. The present study provides an evaluation and the assessment of the modeling system, coupling WRF-ARW/HERMES/CMAQ/BSC-DREAM8b for a full-year simulation in 2004 over Spain.

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Electronegative low-density lipoprotein (LDL(-)) is a minor LDL subfraction present in plasma with increased platelet-activating factor acetylhydrolase (PAF-AH) activity. This activity could be involved in the proinflammatory effects of LDL(-). Our aim was to study the presence of additional phospholipolytic activities in LDL(-).

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The high levels of air pollutants over the North-Western Mediterranean (NWM) exceed the thresholds set in current air quality regulations. They demand a detailed diagnosis of those areas where the exceedances of thresholds related to human health are found. In this sense, there is a need for modelling studies for the specific area of the NWM that take into account the annual cycle to address the diagnosis of air pollution.

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Background: The physicochemical and biological characteristics of electronegative low-density lipoprotein (LDL) (LDL(-)) from type 2 diabetic patients (DM2), before and after insulin therapy, were studied.

Methods: Total LDL was subfractionated in LDL(+) (native LDL) and LDL(-) by anion-exchange chromatography.

Results: The proportion of LDL(-) was increased in plasma from DM2 patients compared to control subjects (13.

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The binding characteristics of electropositive [LDL(+)] and electronegative LDL [LDL(-)] subfractions to the LDL receptor (LDLr) were studied. Saturation kinetic studies in cultured human fibroblasts demonstrated that LDL(-) from normolipemic (NL) and familial hypercholesterolemic (FH) subjects had lower binding affinity than their respective LDL(+) fractions (P < 0.05), as indicated by higher dissociation constant (K(D)) values.

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The current study sought to assess the effect of improving glycemic control in type 2 diabetes on the components of diabetic dyslipidemia, especially low-density lipoprotein (LDL) size. A total of 33 type 2 diabetic patients (48.5% women, age 59.

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To assess postprandial lipidemia in normotriglyceridaemic type 2 diabetic patients treated with diet only, 12 non-obese patients (8 males, hemoglobin A(1c) [HbA(1c)] 6.80 +/- 0.67%) and 14 controls of similar age, body mass index (BMI), and fasting triglyceride (Tg) were given a test meal (58 g fat, 100,000 IU vitamin A).

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To compare the effects of atorvastatin, gemfibrozil, and their combination on the components of diabetic dyslipidemia, 44 type 2 diabetic patients with low density lipoprotein cholesterol (LDLc) levels greater than 100 mg/dl and triglyceride levels less than 400 mg/dl were included. Twelve-week treatments with atorvastatin (10-20 mg/d) and gemfibrozil (900-1200 mg/d) were given in random order in an open, cross-over study and then combined (10 mg atorvastatin and 900 mg gemfibrozil) for 12 additional wk. Triglyceride, LDLc, high density lipoprotein cholesterol (HDLc), non-HDLc, apolipoprotein B (apoB), and LDL size were measured at baseline and after each treatment.

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Background: Electronegative LDL [LDL(-)], a modified subfraction of LDL present in plasma, induces the release of interleukin-8 and monocyte chemotactic protein-1 from cultured endothelial cells.

Methods And Results: We demonstrate that platelet-activating factor acetylhydrolase (PAF-AH) is mainly associated with LDL(-). LDL(-) had 5-fold higher PAF-AH activity than the nonelectronegative LDL subfraction [LDL(+)] in both normolipemic and familial hypercholesterolemic subjects.

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LDL phenotype B is a component of diabetic dyslipidaemia, but its diagnosis is cumbersome. Our aim was to find easily available markers of phenotype B in a group of type 2 diabetic subjects. We studied 123 type 2 diabetic patients (67.

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The immediate effects of intense aerobic exercise on the composition and oxidizability of low- (LDL) and high-density lipoproteins (HDL) were studied in 11 male athletes. Plasma parameters known to affect lipoprotein oxidizability were also evaluated. Lipophilic antioxidants, including alpha-tocopherol and carotenoids, paraoxonase and malondialdehyde (MDA) in plasma remained unchanged after exercise.

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To evaluate the effect of physical exercise on blood pressure, the lipid profile, lipoprotein(a) (Lp(a)), and low-density lipoprotein (LDL) modifications in untrained diabetics, 27 diabetic patients (14 type 1 and 13 type 2) under acceptable and stable glycemic control were studied before and after a supervised 3-month physical exercise program. Anthropometric parameters, insulin requirements, blood pressure, the lipid profile, Lp(a), LDL composition, size, and susceptibility to oxidation, and the proportion of electronegative LDL (LDL(-)) were measured. After 3 months of physical exercise, physical fitness improved (maximal O2 consumption [VO2max], 29.

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