The impact of COVID-19 pandemic in Mediterranean urban air pollution and mobility

Author(s):  
Nikolaos Sifakis ◽  
Maria Aryblia ◽  
Tryfon Daras ◽  
Stavroula Tournaki ◽  
Theocharis Tsoutsos
2008 ◽  
Vol 7 (S1) ◽  
Author(s):  
Karina Karina Abe ◽  
Leticia de Campos Brandao ◽  
Sergio Tufik ◽  
Paulo Hilario do Nascimento Saldiva ◽  
Vania D'Almeida

2020 ◽  
Vol 12 (20) ◽  
pp. 8401
Author(s):  
Jong In Baek ◽  
Yong Un Ban

In terms of urban planning, the impact of urbanization and high density on the environment is a major issue. This study intended to analyze the effect of spatial density characteristics of urban air pollution sources on urban air pollution concentration using a panel model. As the total population density, the number of cars registered per capita, and the total emission facility density increased, together with a closer distance to a thermal power plant, the nitrogen dioxide(NO2) concentration increased. Net population density was also found to have the greatest impact on the structure and density of emission sources of ozone(O3) followed by the number of cars registered per person and the total emission facility density. It was confirmed that particular matter(PM10) concentrations are strongly influenced in positive directions by the spatial density characteristics of emission sources that show significant differences between regions.


2008 ◽  
Vol 42 (3) ◽  
pp. 428-440 ◽  
Author(s):  
Yuval ◽  
Bernanda Flicstein ◽  
David M. Broday

2013 ◽  
Vol 64 (1) ◽  
pp. 23-34 ◽  
Author(s):  
Lilian Calderón-Garcidueñas ◽  
Antonieta Mora-Tiscareño ◽  
Maricela Francolira ◽  
Ricardo Torres-Jardón ◽  
Bernardo Peña-Cruz ◽  
...  

Air pollution induces systemic inflammation, as well as respiratory, myocardial and brain inflammation in children. Peak bone mass is influenced by environmental factors. We tested the hypothesis that six-year-olds with lifetime exposures to urban air pollution will have alterations in inflammatory markers and bone mineral density (BMD) as opposed to low-polluted city residents when matched for BMI, breast feeding history, skin phototype, age, sex and socioeconomic status. This pilot study included 20 children from Mexico City (MC) (6.17 years ± 0.63 years) and 15 controls (6.27 years ± 0.76 years). We performed full paediatric examinations, a history of outdoor exposures, seven-day dietary recalls, serum inflammatory markers and dual-energy X-ray absorptiometry (DXA). Children in MC had significantly higher concentrations of IL-6 (p=0.001), marked reductions in total blood neutrophils (p= 0.0002) and an increase in monocytes (p=0.005). MC children also had an insufficient Vitamin D intake and spent less time outdoors than controls (p<0.001) in an environment characterized by decreased UV light, with ozone and fine particulates concentrations above standard values. There were no significant differences between the cohorts in DXA Z scores. The impact of systemic inflammation, vitamin D insufficiency, air pollution, urban violence and poverty may have long-term bone detrimental outcomes in exposed paediatric populations as they grow older, increasing the risk of low bone mass and osteoporosis. The selection of reference populations for DXA must take into account air pollution exposures.


2020 ◽  
Author(s):  
Mike J. Newland ◽  
Daniel J. Bryant ◽  
Rachel E. Dunmore ◽  
Thomas J. Bannan ◽  
W. Joe F. Acton ◽  
...  

Abstract. The impact of volatile organic compound (VOC) emissions to the atmosphere on the production of secondary pollutants, such as ozone and secondary organic aerosol (SOA), is mediated by the concentration of nitric oxide (NO). Polluted urban atmospheres are typically considered to be high-NO environments, while remote regions such as rainforests, with minimal anthropogenic influences, are considered to be low-NO. Policy to reduce urban air pollution is typically developed assuming that the chemistry is controlled by the high-NO regime. However, our observations from central Beijing show that this simplistic separation of regimes is flawed. Despite being in one of the largest megacities in the world, we observe significant formation of gas and aerosol phase oxidation products associated with the low-NO rainforest-like regime during the afternoon. This is caused by a surprisingly low concentration of NO, coupled with high concentrations of VOCs and of the atmospheric oxidant hydroxyl (OH). Box model calculations suggest that during the morning high-NO chemistry predominates (95 %) but in the afternoon low-NO chemistry plays a greater role (30 %). With increasing global emphasis on reducing air pollution, the modelling tools used to develop urban air quality policy need to adequately represent both high- and low-NO regimes if they are to have utility.


2020 ◽  
Vol 17 (1) ◽  
Author(s):  
Hendrik J. Greve ◽  
Christen L. Mumaw ◽  
Evan J. Messenger ◽  
Prasada R. S. Kodavanti ◽  
Joyce L. Royland ◽  
...  

Abstract Background Air pollution has been linked to neurodegenerative diseases, including Alzheimer’s disease (AD), and the underlying neuroimmune mechanisms remain poorly understood. TREM2 is a myeloid cell membrane receptor that is a key regulator of disease-associated microglia (DAM) cells, where loss-of-function TREM2 mutations are associated with an increased risk of AD. At present, the basic function of TREM2 in neuroinflammation is a point of controversy. Further, the impact of air pollution on TREM2 and the DAM phenotype is largely unknown. Using diesel exhaust (DE) as a model of urban air pollution exposure, we sought to address its impact on TREM2 expression, the DAM phenotype, the association of microglia with the neurovasculature, and the role of TREM2 in DE-induced neuroinflammation. Methods WYK rats were exposed for 4 weeks to DE (0, 50, 150, 500 μg/m3) by inhalation. DE particles (DEP) were administered intratracheally once (600 μg/mouse) or 8 times (100 μg/mouse) across 28 days to male mice (Trem2+/+, Trem2−/−, PHOX+/+, and PHOX−/−). Results Rats exposed to DE exhibited inverted-U patterns of Trem2 mRNA expression in the hippocampus and frontal cortex, while TREM2 protein was globally diminished, indicating impaired TREM2 expression. Analysis of DAM markers Cx3Cr1, Lyz2, and Lpl in the frontal cortex and hippocampus showed inverted-U patterns of expression as well, supporting dysregulation of the DAM phenotype. Further, microglial-vessel association decreased with DE inhalation in a dose-dependent manner. Mechanistically, intratracheal administration of DEP increased Tnf (TNFα), Ncf1 (p47PHOX), and Ncf2 (p67PHOX) mRNA expression in only Trem2+/+ mice, where Il1b (IL-1β) expression was elevated in only Trem2−/− mice, emphasizing an important role for TREM2 in DEP-induced neuroinflammation. Conclusions Collectively, these findings reveal a novel role for TREM2 in how air pollution regulates neuroinflammation and provides much needed insight into the potential mechanisms linking urban air pollution to AD.


2021 ◽  
Author(s):  
Stefanie Meilinger ◽  
Anna Herman-Czezuch ◽  
Armelle Zemo ◽  
Matthias Bebber

&lt;p&gt;In contrast to the German power supply, the energy supply in many West African countries is very unstable. Frequent power outages are not uncommon. Especially for critical infrastructures, such as hospitals, a stable power supply is vital. To compensate for the power outages, diesel generators are often used. In the future, these systems will increasingly be supplemented by PV systems and storage, so that the generator will have to be used less or not at all when needed. For the design and operation of such systems, it is necessary to better understand the atmospheric variability of PV power generation.&amp;#160; For example, there are large variations between rainy and dry seasons, between days with high and low dust levels - caused by sandstorms (harmattan) or urban air pollution.&lt;/p&gt;&lt;p&gt;In our paper, we investigate different aspects of aerosol characteristics on PV hybrid systems in West Africa. Based on measured data from different sources (AERONET, DACCIWA, EnerSHelF), we will investigate the influence of aerosol density and type on PV performance by comparing a non-spectrally resolved (Neher et al., 2017) and a spectrally resolved PV performance model (Herman-Czezuch et al., submitted). Due to the materials used (semiconductors e.g. silicon, gallium arsenide, cadmium telluride), photovoltaic cells are spectrally selective. This means that only radiation of certain wavelengths is converted into electrical energy. A material property called spectral sensitivity characterizes a certain degree of solar radiation conversion into the electric current for each wavelength of sunlight. On the other hand, different types of aerosols can be distinguished by their scattering and absorption properties. A fundamental study of the impact of spectral effects due to different aerosol types is essential to improve PV power predictions under aerosol-dominated situations, such as dust storms or urban smog.&lt;/p&gt;&lt;p&gt;The current study is part of the EnerSHelF (Energy Self-sufficiency of Health Facilities in Ghana) research project funded by the German Federal Ministry of Education and Research (BMBF) and coordinated by the Bonn-Rhein-Sieg University of Applied Sciences (H-BRS)&lt;/p&gt;&lt;p&gt;Here we present model results in which we systematically investigate the impact of aerosols on PV performance for different PV technologies. In addition, we show results of a case study investigating the impact of desert dust on a real PV hybrid system during the harmattan season (Bebber et al., 2021).&lt;/p&gt;&lt;p&gt;&lt;strong&gt;&amp;#160;&lt;/strong&gt;&lt;strong&gt;References&lt;/strong&gt;&lt;/p&gt;&lt;ul&gt;&lt;li&gt;Bebber, M., et al., &amp;#8222;PV-Diesel-Hybrid-System f&amp;#252;r ein Krankenhaus in Ghana - Anbindung eines PV-Batteriespeichermodells an ein bestehendes Generatormodell.&amp;#8220; Hochschule Bonn-Rhein-Sieg, 2021 (IZNE Working Paper Series, Nr. 21/3.) (Research Paper.) ISBN 978-3-96043-091-9&lt;/li&gt; &lt;li&gt;Herman-Czezuch, A., et al., &amp;#8220;Impact of solar spectrum on the efficiency of photovol-taic cells &amp;#8211; spectrally resolved PV performance model&amp;#8221;, submitted to Solar Energy, 2021&lt;/li&gt; &lt;li&gt;Neher, I, et al., &amp;#8220;Impact of aerosols on photovoltaic energy production - Scenarios from the Sahel Zone&amp;#8221;. In: Energy Procedia, Vol.125, 2017, S. 170-179&lt;/li&gt; &lt;/ul&gt;


Sign in / Sign up

Export Citation Format

Share Document