Lynn Waterhouse | PubMed Health

PubMed2003

Responses and sustained interactions in children with mental retardation and autism.

Sustained interactions and responses to social bids made by children with autism and verbal-age-matched children with mental retardation were recorded in two naturalistic settings. Children with autism produced fewer positive responses and more "no responses" than children with mental retardation; both groups were more likely to make positive responses to adults and not to respond to other children. Furthermore, although the frequency of conversations was not different for the two groups, children with autism were significantly less likely to engage in sustained play compared to children with mental retardation. Results suggest that children with autism are able to master the more rote and need-oriented social skills, such as simple conversation, but may not develop other forms of social interactions, like play.

Adolescent↗

PubMed2003

Electrostatic nanolithography in polymers using atomic force microscopy.

The past decade has witnessed an explosion of techniques used to pattern polymers on the nano (1-100 nm) and submicrometre (100-1,000 nm) scale, driven by the extensive versatility of polymers for diverse applications, such as molecular electronics, data storage, optoelectronics, displays, sacrificial templates and all forms of sensors. Conceptually, most of the patterning techniques, including microcontact printing (soft lithography), photolithography, electron-beam lithography, block-copolymer templating and dip-pen lithography, are based on the spatially selective removal or formation/deposition of polymer. Here, we demonstrate an alternative and novel lithography technique--electrostatic nanolithography using atomic force microscopy--that generates features by mass transport of polymer within an initially uniform, planar film without chemical crosslinking, substantial polymer degradation or ablation. The combination of localized softening of attolitres (10(2)-10(5) nm3) of polymer by Joule heating, extremely non-uniform electric field gradients to polarize and manipulate the soften polymer, and single-step process methodology using conventional atomic force microscopy (AFM) equipment, establishes a new paradigm for polymer nanolithography, allowing rapid (of the order of milliseconds) creation of raised (or depressed) features without external heating of a polymer film or AFM tip-film contact.

Microscopy, Atomic Force↗