Direct e-beam lithography of PDMS

In this paper, the viability of directly exposing thin films of liquid poly(dimethylsiloxane) (PDMS) to electron beam (e-beam) irradiation using e-beam lithographic methods for the purpose of creating permanent micro-scale components has been investigated. By exposing 1.1 μm thickness PDMS films to doses in the range 10–50,000 μC/cm2, it was discovered that the structure of the resultant film exhibits four distinct phases, depending upon the exposure dose. These phases were manifested in both the resultant Young’s modulus and thickness of the developed film. It was found that there is a critical dose whereupon the resultant film undergoes solidification and adheres to the counter surface sufficiently to survive the development process. It has been shown that the Young’s modulus of the solid film can be varied over seven orders of magnitude, from that of a viscoelastic material through a rubbery regime to that of a glassy one, by increasing the e-beam dose. At higher doses, excessive backscattering was observed, as well as film swelling, resulting in poor spatial resolution

A defect in KCa3.1 channel activity limits the ability of CD8+T cells from cancer patients to infiltrate an adenosine-rich microenvironment

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Tapered fibertrodes for optoelectrical neural interfacing in small brain volumes with reduced artefacts

Deciphering the neural patterns underlying brain functions is essential to understanding how neurons are organized into networks. This deciphering has been greatly facilitated by optogenetics and its combination with optoelectronic devices to control neural activity with millisecond temporal resolution and cell type specificity. However, targeting small brain volumes causes photoelectric artefacts, in particular when light emission and recording sites are close to each other. We take advantage of the photonic properties of tapered fibres to develop integrated ‘fibertrodes’ able to optically activate small brain volumes with abated photoelectric noise. Electrodes are positioned very close to light emitting points by non-planar microfabrication, with angled light emission allowing the simultaneous optogenetic manipulation and electrical read-out of one to three neurons, with no photoelectric artefacts, in vivo. The unconventional implementation of two-photon polymerization on the curved taper edge enables the fabrication of recoding sites all around the implant, making fibertrodes a promising complement to planar microimplants

FILOSE: a svenning* robot

The trend of biomimetic underwater robots has emerged as a search for an alternative to traditional propeller-driven underwater vehicles. The drive of this trend, as in any other areas of bioinspired and biomimetic robotics, is the belief that exploiting solutions that evolution has already optimized leads to more advanced technologies and devices