Identifying Patterns and Sources of Fine and Ultrafine Particulate Matter in London Using Mobile Measurements of Lung-Deposited Surface Area.

We performed more than a year of mobile, 1 Hz measurements of lung-deposited surface area (LDSA, the surface area of 20-400 nm diameter particles, deposited in alveolar regions of lungs) and optically assessed fine particulate matter (PM), black carbon (BC), and nitrogen dioxide (NO) in central London. We spatially correlated these pollutants to two urban emission sources: major roadways and restaurants. We show that optical PM is an ineffective indicator of tailpipe emissions on major roadways, where we do observe statistically higher LDSA, BC, and NO.

Revision of the whitefly genus, Asterochiton Maskell (Hemiptera: Aleyrodidae) from New Zealand, a study of intraspecific variation.

All the specimens of Asterochiton species (Hemiptera: Aleyrodidae) on slides in the New Zealand Arthropod Collection, Auckland, were examined. The study reveals that the genus is currently restricted to New Zealand and is redescribed here. Obvious generic characters are the sub-elliptical to sub-circular puparium with distinct invaginations at the thoracic and caudal pores.

Facile synthesis of titania nanowires via a hot filament method and conductometric measurement of their response to hydrogen sulfide gas.

Titania nanostructures are of increasing interest for a variety of applications, including photovoltaics, water splitting, and chemical sensing. Because of the photocatalytical properties of TiO₂, chemical processes that occur at its surface can be exploited for highly efficient nanodevices. A facile and fast synthesis route has been explored that is free of catalysts or templates.

Laser ablation direct writing of metal nanoparticles for hydrogen and humidity sensors.

A UV pulsed laser writing technique to fabricate metal nanoparticle patterns on low-cost substrates is demonstrated. We use this process to directly write nanoparticle gas sensors, which operate via quantum tunnelling of electrons at room temperature across the device. The advantages of this method are no lithography requirements, high precision nanoparticle placement, and room temperature processing in atmospheric conditions.