RESUMO
The fabrication of functional thin films and devices by direct deposition of nanoparticles from the gas phase is a promising approach enabling, for instance, the integration of complex analytical and sensing capabilities on microfabricated platforms. Aerosol-based techniques ensure large-scale nanoparticle production and they are potentially suited for this goal. However, they are not adequate in terms of fine control over the lateral resolution of the coatings, mild processing conditions (avoiding high temperature and aggressive chemicals), low contamination and compatibility with microfabrication processes. Here we report the high-rate and efficient production of functional nanostructured films by nanoparticle assembling obtained by the combination of flame spray pyrolysis and supersonic expansion. Our approach merges the advantages of flame spray pyrolysis for bulk nanopowders such as process stability and wide material library availability with those of supersonic cluster beam deposition in terms of lateral resolution and of direct integration of nanomaterials on devices. We efficiently produced nanostructured films and devices (such as gas sensors) using metal oxide, pure noble metal and oxide-supported noble metal nanoparticles.
RESUMO
Cluster headache is a clinical entity characterised by strictly unilateral head pain attacks accompanied by ipsilateral autonomic phenomena. We report two patients who had pain episodes mimicking cluster headache attacks, and who experienced a total or partial Horner's syndrome ipsilaterally to pain, persisting for 48 h after the last attack. A dissection of the ipsilateral internal carotid artery at the extra-intracranial passage was present in both cases. These cases highlight the need for extensive neuroradiological investigation in cluster headache patients when atypical features are present.