The Environmental scanning electron microscopy (ESEM) has been used in a preliminary study to determine the size and morphology of fine particulate matter (PM). This was done with several samples collected inside public transit buses fueled with a 20 percent biodiesel blend of biodiesel and ultra-low sulfur diesel (B20). As the technique is nondestructive, particles of interest can be relocated...

The Particle Measurement Programme Informal Working Group (PMP-IWG) coordinated a global interlaboratory study (ILS) on brake wear particle emissions with the participation of 16 testing facilities. Two articles present main outcomes ILS: (I) Particulate matter mass (PM), and (II) Number (PN) emissions. test matrix covered wide variety systems configurations. tested disc brakes were found to em...

In the prospect of limited energy resources and climate change, effects of alternative biofuels on primary emissions are being extensively studied. Our two recent studies have shown that biodiesel fuel composition has a significant impact on primary particulate matter emissions. It was also shown that particulate matter caused by biodiesels was substantially different from the emissions due to ...

Fungal spores can account for large proportions of air particulate matter, and they may potentially influence the hydrological cycle and climate as nuclei for water droplets and ice crystals in clouds, fog, and precipitation. Moreover, some fungi are major pathogens and allergens. The diversity of airborne fungi is, however, not well-known. By DNA analysis we found pronounced differences in the...

We studied acute responses of rat lungs to inhalation of urban particulate matter and ozone. Exposure to particles (40 mg/m3 for 4 hours; mass median aerodynamic diameter, 4 to 5 microm; Ottawa urban dust, EHC-93), followed by 20 hours in clean air, did not result in acute lung injury. Nevertheless, inhalation of particles resulted in decreased production of nitric oxide (nitrite) and elevated ...

Lotic ecosystems are substantially different than most other ecosystems because the continuous unidirectional flow through the system tends to transport matter to downstream reaches. This gives rise to the common erroneous view of streams as conduits or pipes. The process of retention removes matter from transport and makes it available for utilization by stream biota, thus providing a critical...

Nitric oxide and cytokines constitute the molecular markers and the intracellular messengers of inflammatory conditions which are derived from the activation of the NF-kappaB pathway and the transcription of proinflammatory genes. Sepsis occurs with an exacerbated inflammatory response that damages tissue mitochondria and impairs bioenergetic processes. One of the current hypotheses for the mol...

An intensive particle monitoring study was conducted in homes in the Boston, Massachusetts, area during the winter and summer of 1996 in an effort to characterize sources of indoor particles. As part of this study, continuous particle size and mass concentration data were collected in four single-family homes, with each home monitored for one or two 6-day periods. Additionally, housing activity...