Aerosol Jet Printing (AJP) is an emerging contactless direct write approach aimed at the production of fine features on a wide range of substrates. Originally developed for the manufacture of electronic circuitry, the technology has been explored for a range of applications, including, active and passive electronic components, actuators, sensors, as well as a variety of selective chemical and biological responses. Freeform deposition, coupled with a relatively large stand-off distance, is enabling researchers to produce devices with increased geometric complexity compared to conventional manufacturing or more commonly used direct write approaches. Wide material compatibility, high resolution and independence of orientation have provided novelty in a number of applications when AJP is conducted as a digitally driven approach for integrated manufacture. This overview of the technology will summarise the underlying principles of AJP, review applications of the technology and discuss the hurdles to more widespread industry adoption. Finally, this paper will hypothesise where gains may be realised through this assistive manufacturing process.

Whether the brain represents facial expressions as perceptual continua or as emotion categories remains controversial. Here, we measured the neural response to morphed images to directly address how facial expressions of emotion are represented in the brain. We found that face-selective regions in the posterior superior temporal sulcus and the amygdala responded selectively to changes in facial expression, independent of changes in identity. We then asked whether the responses in these regions reflected categorical or continuous neural representations of facial expression. Participants viewed images from continua generated by morphing between faces posing different expressions such that the expression could be the same, could involve a physical change but convey the same emotion, or could differ by the same physical amount but be perceived as two different emotions. We found that the posterior superior temporal sulcus was equally sensitive to all changes in facial expression, consistent with a continuous representation. In contrast, the amygdala was only sensitive to changes in expression that altered the perceived emotion, demonstrating a more categorical representation. These results offer a resolution to the controversy about how facial expression is processed in the brain by showing that both continuous and categorical representations underlie our ability to extract this important social cue.face | temporal lobe | fMRI T he ability to visually encode changes in facial musculature that reflect emotional state is essential for effective social communication (1). Models of face processing have proposed either that the perception of facial expression is dependent on a continuous neural representation of gradations in expression along critical dimensions (2, 3) or that it is based primarily on the assignment of expressions to discrete emotion categories (4, 5).Although they are usually treated as incompatible opposites, there is evidence consistent with both the continuous and categorical approaches to facial expression perception (6). The categorical perspective is based on the idea that distinct neural or cognitive states underpin a set of basic facial expressions (5). Evidence for categorical perception of expression is shown by the consistency with which the basic emotions are recognized (7) and the greater sensitivity to changes in facial expression that alter the perceived emotion (8, 9). In contrast, continuous or dimensional models are better able to explain the systematic confusions that occur when labeling facial expressions (2) and can account for variation in the way that basic emotions are expressed (10) and the fact that we are readily able to perceive differences in intensity of a given emotional expression (11,12).The aim of this study is to ask whether primarily categorical or continuous representations of facial expression are used in different regions of the human brain. Neuroimaging studies have identified a number of face-selective regions that are involved in the perception of facial express...

With the maturity of surgical robotic systems based on traditional rigid-link principles, the rate of progress slowed as limits of size and controllable degrees of freedom were reached. Continuum robots came with the potential to deliver a step change in the next generation of medical devices, by providing better access, safer interactions and making new procedures possible. Over the last few years, several continuum robotic systems have been launched commercially and have been increasingly adopted in hospitals. Despite the clear progress achieved, continuum robots still suffer from design complexity hindering their dexterity and scalability. Recent advances in actuation methods have looked to address this issue, offering alternatives to commonly employed approaches. Additionally, continuum structures introduce significant complexity in modelling, sensing, control and fabrication; topics which are of particular focus in the robotics community. It is, therefore, the aim of the presented work to highlight the pertinent areas of active research and to discuss the challenges to be addressed before the potential of continuum robots as medical devices may be fully realised.

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The use of Rapid Prototyping (RP) techniques for the production of end-use parts is increasing to a stage where Rapid Manufacturing is being undertaken. This paper documents significant initial investigations into the properties of Accura SI40 and SL7560 resins which represent two state of the art stereolithography resins that are aimed at end-use part manufacture. This information has previously been unavailable and is vital for their consideration in end-use part manufacture. The impact of various levels of post curing (ultraviolet and thermal) on the tensile, flexural and impact properties are investigated and correlated with differential scanning calorimetry (DSC) analysis. The isotropy/anisotropy nature of the two materials and also the effect of the notch creation method on the impact resistance were also studied.