Outdoor aerosol particles were characterized in industrial area of Samalut city (El-minia/Egypt) using low pressure Berner cascade impactor as an aerosol sampler. The impactor operates at 1.7 m(3)/h flow rate. Seven elements were investigated including Ca, Ba, Fe, K, Cu, Mn and Pb using atomic absorption technique. The mean mass concentrations of the elements ranged from 0.42 ng/m(3) (for Ba) t...

The purpose of this paper is to review the recent literature related to invasive mechanical ventilation, NIV, pediatric mechanical ventilation, and aerosol therapy. Topics covered related to invasive mechanical ventilation topics include the role of PEEP in providing lung protection during mechanical ventilation, unconventional modes for severe hypoxemia, and strategies to improve patient-venti...

This paper is the first part of a two-part study that aims to retrieve aerosol particle size distribution (PSD) and refractive index from the multispectral and multiangular polarimetric measurements taken by the new-generation Sun photometer as part of the Aerosol Robotic Network (AERONET). It provides theoretical analysis and guidance to the companion study in which we have developed an invers...

[1] The effect of anthropogenic aerosols on clouds has the potential to be a key component for climate change predictions, yet is one of the least understood. It is possible that high aerosol loading can change the convection intensity and hence the electrical activity of thunderstorm clouds. Focusing on the Amazon dry season, where thousands of man‐made forest fires inject smoke into the atmos...

Success of NASA’s Phytoplankton, Aerosol, Cloud, and ocean Ecosystem (PACE) mission 1 depends critically on atmospheric correction to retrieve inherent properties of oceanic waters. 2 Previously unexplored UV wavelengths are the most challenging to correct due to large signals 3 from Rayleigh and aerosol scattering. The dominant Rayleigh component makes it difficult to 4 separate absorption by ...

[1] Simulations with the CAM3 climate model show that prescribed heating by anthropogenic aerosols significantly affects cloud cover. Globally the dominant effect is a decrease in mid‐level clouds, which contributes to a semi‐ direct effect (SDE) that warms the surface by 0.5 W m. The SDE negates some of the impact of absorbing aerosol on surface fluxes, up to 50% over the Northern Hemisphere e...

The net shortwave radiative impact of aerosol on simulations of two shallow marine cloud cases is investigated using a Monte Carlo radiative transfer model. For a shallow cumulus case, increased aerosol concentrations are associated not only with smaller droplet sizes but also reduced cloud fractions and cloud dimensions, a result of evaporation-induced mixing and a lack of precipitation. Three...

The formation of secondary organic aerosol (SOA) results from the absorption of gasphase organic oxidation products by airborne aerosol. Historically, modeling the formation of SOA has relied on relatively crude estimates of the capability of given parent hydrocarbons to form SOA. In more recent work, surrogate organic oxidation products have been separated into two groups, hydrophobic and hydr...

Recent observations reveal a seasonally occurring layer of aerosol located from 0◦ to 100◦E, 20◦ to 45◦N and extending vertically from about 13 km to 18 km; this has been termed the Asian tropopause aerosol layer (ATAL), and its existence is closely associated with the Asian summer monsoon circulation. Observational studies argue that the ATAL is a recent phenomenon, as the layer is not observe...

Environmental and occupational monitoring of hazardous aerosols, especially bioterrorism threats by way of dispersal of pathogenic bioaerosols, requires advanced systems that can identify harmful bioaerosol particles in quasi real-time and in situ. Instruments presently available to identify airborne biowarfare agents (BWA), mostly based on biochemical technologies, cannot be run continuously a...