background & purpose: air pollution has been known as one of the most effective factors on cardiovascular, pulmonary and infectious diseases. this study aims to determine the relation between mortality rate and air pollution in mashhad during 2007-2009. materials & methods: data of air pollution, mortality rate and geographic factors were collected during 2007-2009 and analyzed. mortality rate,...

Enhanced ultraviolet-B (UV-B) radiation and elevated tropospheric ozone alone may inhibit the growth of agricultural crops. However, research regarding their combined effects on growth and biochemical properties of roots is still scarce. Using open top chambers, we monitored the response of growth, secondary metabolites, endogenous hormones and enzyme activities of soybean roots to elevated O3 ...

the structural and energetic characteristics of o3–h2o complexes have been investigated by means of b3lyp, mp2, mp4(sdtq), ccsd(t) and qcisd(t) methods in conjunction with the aug-cc-pvdz and aug-cc-pvtz basis sets. six conformers were found for the o3–h2o complex. two different intermolecular interactions were expected to participate in the formation of complexes, namely conventional o∙∙∙h hyd...

The current network of ground-based monitors for ozone (O3) is limited due to the spatial heterogeneity of O3 at the surface. Satellite measurements can provide a solution to this limitation, but the lack of sensitivity of satellites to O3 within the boundary layer causes large uncertainties in satellite retrievals at the near-surface. The vertical variability of O3 was investigated using ozone...

Elevated atmospheric concentrations of CO2 and O3 are known to alter the chemical composition of foliage, which in turn may affect the performance of herbivorous insects. We investigated the independent and interactive effects of CO2 and O3 on foliar quality of paper birch (Betula papyrifera Marshall) and the consequences of chemical changes for performance of the whitemarked tussock moth Orgyi...

For the purposes of developing optimal emissions control strategies, efficient approaches are needed to identify the major sources or groups of sources that contribute to elevated ozone (O3) concentrations. Source-based apportionment techniques implemented in photochemical grid models track sources through the physical and chemical processes important to the formation and transport of air pollu...

A real-time air quality forecasting system (Eta-Community Multiscale Air Quality [CMAQ] model suite) has been developed by linking the National Centers for Environmental Estimation Eta model to the U.S. Environmental Protection Agency (EPA) CMAQ model. This work presents results from the application of the Eta-CMAQ modeling system for forecasting ozone (O3) over the Northeastern United States d...

In vitro exposures to air pollutants could, in theory, facilitate a rapid and detailed assessment of molecular mechanisms of toxicity. However, it is difficult to ensure that the dose of a gaseous pollutant to cells in tissue culture is similar to that of the same cells during in vivo exposure of a living person. The goal of the present study was to compare the dose and effect of O3 in airway c...

Climate change may increase the frequency and intensity of ozone episodes in future summers in the United States. However, only recently have models become available that can assess the impact of climate change on O3 concentrations and health effects at regional and local scales that are relevant to adaptive planning. We developed and applied an integrated modeling framework to assess potential...

A multi-layer ozone (O3) dry deposition model has been implemented into SOSAA (a model to Simulate the concen-trations of Organic vapours, Sulphuric Acid and Aerosols) to improve the representation of O3 concentration and flux withinand above the forest canopy in the planetary boundary layer. We aim to predict the O3 uptake by a boreal forest canopy undervarying environmental condit...