Platelet-activating factor (PAF) is a proinflammatory lipid that has both platelet- and phagocyte-stimulating properties. Because several known activators of calcium-, phospholipid-dependent protein kinase (protein kinase c, PKC) also stimulate neutrophil responses and because neutrophil stimuli such as phorbol diesters and the chemotactic peptide f-Met-Leu-Phe are reported to increase protein ...

Little is known concerning the factors which might control the distribution of viral abundance in oceanic environments and the relationship of viruses to the oceanic DNA pool. We have measured the distribution of viruses, bacterioplankton and phytoplankton in the subtropical southeastern Gulf of Mexico and related these parameters to the distribution of DNA (dissolved and particulate) in these ...

Particulate matter contamination is known to become wet and therefore ionically conductive and corrosive if the humidity in the environment rises above the deliquescence relative humidity (DRH) of the particulate matter. In wet condition, particulate matter can electrically bridge closely spaced features on printed circuit boards (PCBs), leading to their electrical failure. Failures attributed ...

The riverine transport of elements from land to ocean is an integral flux for many element cycles and an important climate regulating process over geological timescales. This flux consists of both dissolved and particulate material. The world’s rivers are estimated to transport between 16.6 and 30 Gt yr 1 of particulate material, considerably higher than the dissolved flux of 1 Gt yr . Therefor...

Particulate matter of vehicle exhaust is known to contain carcinogenic compounds such as polycyclic aromatic hydrocarbons (PAH) and is suggested to increase lung cancer risk in humans. This study examines the differences in diesel and gasoline-derived PAH binding to DNA in a human bronchial epithelial cell line (BEAS-2B). Particulate matter (PM) of gasoline exhaust was collected from passenger ...

1. The properties of rat brain lysophospholipase were investigated. Three subcellular fractions were employed: a particulate preparation which sedimented at 26,000 X g, a microsomal preparation which sedimented at 100,000 X g, and the supernatant of the above. The soluble enzyme represented only a small fraction of the total activity; it was further purified by treatment with protamine and ammo...

Little is known concerning the factors which might control the distribution of viral abundance in oceanic environments and the relationship of viruses to the oceanic DNA pool. We have measured the distribution of viruses, bacterioplankton and phytoplankton in the subtropical southeastern Gulf of Mexico and related these parameters to the distribution of DNA (dissolved and particulate) in these ...

Autoxidation is a complex abiotic degradation process, and while it has long been known and well studied in biological compounds, it has been widely overlooked in environmental samples and as a part of environmental processes. With recent observations showing the magnitude of the involvement of autoxidation in coastal environments, it has become critical to better understand how and why this de...

Several chronic inhalation bioassays of poorly soluble, nonfibrous particles have resulted in an increased incidence of lung tumors in rats, no increase in lung tumors in Syrian hamsters, and inconsistent results in mice. These results have raised concerns that rats may be more prone than other species to develop persistent pulmonary epithelial hyperplasia, metaplasia, and tumors in response to...

The performance of a particulate-biofilm, expanded-bed process for nitrification of activated sludge final effluent (ASFE) is reported for a plant receiving mixed industrial and domestic wastewater. The support material for the particulate-biofilms was glassy coke, to which the nitrifying bacteria attached and formed a highly active biofilm. An average nitrification rate of 1.7+/-0.6 kg m(expan...