State space properties of Boolean networks trained for sequence tasks

In a recent work, it has been shown that Boolean networks (BN), a well-known genetic regulatory network model, can be utilised to control robots. In this work, we use a genetic algorithm to train robots controlled by a BN so as to accomplish a sequence learning task. We analyse the robots' dynamics by studying the corresponding BNs' phase space. Our results show that a phase space structure emerges enabling the robot to have memory of the past and to exploit this piece of information to choose the next action to perform. This finding is in accordance with previous results on minimally cognitive behaviours and shows that the phase space of Boolean networks can be shaped by the learning process in such a way that the robot can accomplish non-trivial tasks requiring the use of memory

128-slice CT angiography of the aorta without ECG-gating: efficacy of faster gantry rotation time and iterative reconstruction in terms of image quality and radiation dose

Objective: To evaluate image quality and radiation dose of non ECG-gated 128-slice CT angiography of the aorta (CTAA) with fast gantry rotation time and iterative reconstruction. Methods: Four hundred and eighty patients underwent non ECG-gated CTAA. Qualitative and quantitative image quality assessments were performed. Radiation dose was assessed and compared with the dose of patients who underwent ECG-gated CTAA (n = 126) and the dose of previous CTAA performed with another CT (n = 339). Results: Image quality (aortic root-ascending portion) was average-to-excellent in more than 94 % of cases, without any non-diagnostic scan. For proximal coronaries, image quality was average-to-excellent in more than 50 %, with only 21.5 % of non-diagnostic cases. Quantitative analysis results were also good. Mean radiation dose for thoracic CTAA was 5.6 mSv versus 20.6 mSv of ECG-gated protocol and 20.6 mSv of 16-slice CTAA scans, with an average dose reduction of 72.8 % (p < 0.001). Mean radiation dose for thoracic-abdominal CTAA was 9.7 mSv, versus 20.9 mSv of 16-slice CTAA scans, with an average dose reduction of 53.6 % (p < 0.001). Conclusions: Non ECG-gated 128-slice CTAA is feasible and able to provide high quality visualization of the entire aorta without significant motion artefacts, together with a considerable dose and contrast media volume reduction. Key Points: \u2022 CT image quality of aortic root-ascending aorta is challenging. \u2022 Non ECG-gated scans are often limited by pulsatility artefacts. \u2022 ECG-gated examinations are usually limited by high radiation doses. \u2022 Non ECG-gated 128-slice low dose CTAA provides high quality images. \u2022 128-slice CTAA low dose protocol could frequently replace ECG-gated CTAA. \ua9 2015, European Society of RadiologyCT image quality of aortic root-ascending aorta is challenging. \u2022 Non ECG-gated scans are often limited by pulsatility artefacts. \u2022 ECG-gated examinations are usually limited by high radiation doses. \u2022 Non ECG-gated 128-slice low dose CTAA provides high quality images. \u2022 128-slice CTAA low dose protocol could frequently replace ECG-gated CTA

A Blockchain-Controlled Physical Robot Swarm Communicating via an Ad-Hoc Network

info:eu-repo/semantics/publishe

Automatic design of communication-based behaviors for robot swarms

We introduce Gianduja, an automatic design method that generates communication-based behaviors for robot swarms. Gianduja extends Chocolate, a previously published design method. It does so by providing the robots with the capability to communicate using one message. The semantics of the message is not a priori fixed. It is the automatic design process that implicitly defines it, on a per-mission basis, by prescribing the conditions under which the message is sent by a robot and how the receiving peers react to it. We empirically study Gianduja on three missions and we compare it with the aforementioned Chocolate and with EvoCom, a rather standard evolutionary robotics method that generates communication-based behaviors. We evaluate the behaviors produced by the three automatic design methods on a swarm of 20 e-puck robots. The results show that Gianduja uses communication meaningfully and effectively in all the three missions considered. The aggregate results indicate that, on the three missions considered, Gianduja performs significantly better than the two other methods under analysis.SCOPUS: cp.kinfo:eu-repo/semantics/publishe