Ultrafine particles (UFPs; diameter less than 100 nm) are ubiquitous in urban air, and an acknowledged risk to human health. Globally, the major source for urban outdoor UFP concentrations is motor traffic. Ongoing trends towards urbanisation and expansion of road traffic are anticipated to further increase population exposure to UFPs. Numerous experimental studies have characterised UFPs in in...

Objectives. The aim of this study was to compare a large set of resin composites suitable for application in stress-bearing areas on the basis of their consistency. Methods. A variety of posterior resin composites were tested using an apparatus that was originally designed for determination of the consistency of elastomeric impression materials (ISO 4823,1992)*The consistency of a standardized ...

Nanotechnologies are among the fastest growing areas of scientific research, and have important applications in a wide variety of fields. At the same time, scientists and regulators are concerned about the potential health and environmental risks related to the widespread production and use of the nanomaterials created by these technologies. Several recent animal and cell culture studies have s...

This paper summarizes recent efforts to evaluate the potential for the formation of a metal matrix nanocomposite (MMNC) by processing two commercial bulk metals of aluminum and magnesium alloy through high-pressure torsion (HPT) at room temperature. After significant evolutions in microstructures, successful fabrication of an Al-Mg hybrid system was demonstrated by observing unique microstructu...

Ultrafine and well dispersed CoAuPd nanoparticles grown on a DNA-reduced-graphene-oxide (DNA-rGO) composite have been successfully synthesized using a DNA-directed method. The resultant CoAuPd/DNA-rGO composite exhibits high activity and 100% H2 selectivity toward the dehydrogenation of formic acid without any additive at 298 K.

BACKGROUND Daily variations in ambient particulate air pollution have been associated with respiratory mortality and morbidity. AIMS To assess the associations between urinary concentration of lung Clara cell protein CC16, a marker for lung damage, and daily variation in fine and ultrafine particulate air pollution. METHODS Spot urinary samples (n = 1249) were collected biweekly for six mon...

Ultrafine particles have been shown to induce pro-inflammatory effects both in vivo and in vitro. Increased expression of pro-inflammatory genes probably requires the activation of specific transcription factors such as nuclear factor kappa B (NF-kappaB) via a number of possible pathways including Ca2+ and reactive oxygen species. The fluorescent dye fura 2, was used to measure cytosolic Ca2+ i...

Production of new particles over forests is an important source of cloud condensation nuclei that can affect climate. While such particle formation events have been widely observed, their formation mechanisms over forests are poorly understood. Our observations made in a mixed deciduous forest with large isoprene emissions during the summer displayed a surprisingly rare occurrence of new partic...