Ozone is one of the major city air pollutants. Since it is known to induce the overexpression of superoxide-dismutase in various models, and is also a powerful oxidant, we tested if ozone can induce the expression of the soxRS regulon of Escherichia coli, which is activated by superoxide and nitric oxide. A sub-lethal exposure to ozone was unable to activate the expression of soxS'::lacZ transc...

[1] We examine the impact of assimilating ozone observations from the Tropospheric Emission Spectrometer (TES) on North American surface ozone abundances in the GEOS-Chem model in August 2006. The assimilation reduces the negative bias in the modeled free tropospheric ozone, which enhances the ozone flux into the boundary layer. Surface ozone abundances increased by as much as 9 ppb in western ...

In order to explore the temporal-spatial patterns and possible health effects of ozone in Shenzhen, daily concentrations of ozone and the daily mortality caused by cardiovascular and respiratory diseases were collected. Using Geographic Information System (GIS) and SPSS, the spatial and temporal patterns of ozone in Shenzhen were illustrated. Using a generalized additive model (GAM), the associ...

The new CHEM2D-Ozone Photochemistry Parameterization (CHEM2D-OPP) for high-altitude numerical weather prediction (NWP) systems and climate models specifies the net ozone photochemical tendency and its sensitivity to changes in ozone mixing ratio, temperature and overhead ozone column based on calculations from the CHEM2D interactive middle atmospheric photochemical transport model. We evaluate ...

[1] Continuous surface-layer ozone flux measurements over the polar, year-round snowpack at Summit, Greenland, resulted in deposition velocities (vd) that were smaller than most previous assumptions and model inputs. Substantial seasonal differences were seen in the ozone vd behavior. Spring, daytime ozone vd values showed low variability and were consistently 0.01 cm s . During summer, ozone f...

Surface ozone pollution has been a persistent environmental problem in the US and Europe as well as the developing countries. A key prerequisite to find effective alternatives to meeting an ozone air quality standard is to understand the importance of local anthropogenic emissions, the significance of biogenic emissions, and the contribution of long-range transport. In this study, an air qualit...

The factors involved in evaluations of effects of volatile organic compound (VOC) and oxides of nitrogen emissions from motor vehicles on ground-level ozone are reviewed. The chemical basis for ozone formation, the computer models and chemical mechanisms used for predicting ozone impacts, and methods for quantifying differences among VOCs in their ozone impacts, are discussed. It is recommended...

Laboratory design of an ozone concentration regulator which is build on the theory of continuity equation for gas flow in parallel pipes in conjunction with the ozone elimination potentials of an ozone destructor is presented. At an initial oxygen flow rate of 33.33 cms, ozone concentration was generated and varied between 429.30 parts per million (ppm) to 3826.60 ppm. Similarly at an initial o...

BACKGROUND Mechanisms of cardiovascular injuries from exposure to gas and particulate air pollutants are unknown. OBJECTIVE We sought to determine whether episodic exposure of rats to ozone or diesel exhaust particles (DEP) causes differential cardiovascular impairments that are exacerbated by ozone plus DEP. METHODS AND RESULTS Male Wistar Kyoto rats (10-12 weeks of age) were exposed to ai...

Inexpensive devices to measure solar UV irradiance are available to monitor atmospheric ozone, for example, total ozone portable spectroradiometers (TOPS instruments). A procedure to convert these measurements into ozone estimates is examined. For well-characterized filters with 7-nm FWHM bandpasses, the method provides ozone values (from 304- and 310-nm channels) with less than 0.4% error attr...