A man with a spinal-cord injury (right) prepares for a virtual cycle race in which competitors steer avatars using brain signals. COMMENT © 2 0 1 7 M a c m i l l a n P u b l i s h e r s L i m i t e d , p a r t o f S p r i n g e r N a t u r e . A l l r i g h t s r e s e r v e d .example. Moreover, researchers can already interpret a person's neural activity from functional magnetic resonance imaging scans at a rudimentary level 1 -that the individual is thinking of a person, say, rather than a car.It might take years or even decades until BCI and other neurotechnologies are part of our daily lives. But technological developments mean that we are on a path to a world in which it will be possible to decode people's mental processes and directly manipulate the brain mechanisms underlying their intentions, emotions and decisions; where individuals could communicate with others simply by thinking; and where powerful computational systems linked directly to people's brains aid their interactions with the world such that their mental and physical abilities are greatly enhanced.Such advances could revolutionize the treatment of many conditions, from brain injury and paralysis to epilepsy and schizophrenia, and transform human experience for the better. But the technology could also exacerbate social inequalities and offer corporations, hackers, governments or anyone else new ways to exploit and manipulate people. And it could profoundly alter some core human characteristics: private mental life, individual agency and an understanding of individuals as entities bound by their bodies.It is crucial to consider the possible ramifications now.The Morningside Group comprises neuroscientists, neurotechnologists, clinicians, ethicists and machine-intelligence engineers. It includes representatives from Google and Kernel (a neurotechnology start-up in Los Angeles, California); from international brain projects; and from academic and research institutions in the United States, Canada, Europe, Israel, China, Japan and Australia. We gathered at a workshop sponsored by the US National Science Foundation at Columbia University, New York, in May 2017 to discuss the ethics of neurotechnologies and machine intelligence.We believe that existing ethics guidelines are insufficient for this realm 2 . These include the Declaration of Helsinki, a statement of ethical principles first established in 1964 for medical research involving human subjects (go.nature.com/2z262ag); the Belmont Report, a 1979 statement crafted by the US National Commission for the Protection of Human Subjects of Biomedical and Behavioural Research (go.nature.com/2hrezmb); and the Asilomar artificial intelligence (AI) statement of cautionary principles, published early this year and signed by business leaders and AI researchers, among others (go.nature.com/2ihnqac).To begin to address this deficit, here we lay out recommendations relating to four areas of concern: privacy and consent; agency and identity; augmentation; and bias. Different nations and people of varying re...

The ability of dynamic extraction of remote sounds is very appealing. In this manuscript we propose an optical approach allowing the extraction and the separation of remote sound sources. The approach is very modular and it does not apply any constraints regarding the relative position of the sound sources and the detection device. The optical setup doing the detection is very simple and versatile. The principle is to observe the movement of the secondary speckle patterns that are generated on top of the target when it is illuminated by a spot of laser beam. Proper adaption of the imaging optics allows following the temporal trajectories of those speckles and extracting the sound signals out of the processed trajectory. Various sound sources are imaged in different spatial pixels and thus blind source separation becomes a very simple task.

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The interest in line arrangements was first stimulated by an early work of Zariski [10], where he showed how the topology of a nodal curve embedding in CP 2 could be understood, using degenerations of plane nodal curves of given degree n to a union of n lines in general position.Zariski's work was not complete, because it had used an existence statement of Severi, which was correctly proved only a few years ago by J. Harris [3]. Nevertheless Zariski's main result, namely, the commutativity of nl(ZP2 -C,*), C any nodal curve, was proved, without a reference to Severi, by W. Fulton and P. Deligne in 1980 before Harris' work [2],[1]. However, the most important singular plane curves, namely, those which appear as singularities of proper stable morphisms onto CP 2 (like branch curves of generic projections and their duals) usually have not only nodes, but also cusps. Such curves are called cuspidalplane curves. Not much is known about them in general. Therefore, a study of concrete series of examples, in other words, a continous experimental work seems to be necessary and important.It appears that the Severi-Zariski approach for nodal curves could be extended to cuspidal curves in very many interesting cases, local or global. One has to consider, however, not the arrangements of lines but those of lines and conics, where tangency points become the source of cusps in the regeneration process. For that, one has to allow also a doubling of some components of the configuration during the regeneration.Let us consider the case of a branch curve S for a generic projection f: V ---) CP 2, where V is a non-singular algebraic surface. We shall synthesize S from "simple elements." The most natural way to see how it could be done is to degenerate f: V --~ ~p2 to some f0:V0 ~ CP2, where V 0 is "simpler" than V. Assume, for instance, that V 0 = WlUW2, where both W 1 and W 2 are non-singular, intersecting transversally in V 0, and f0:WlkJW2 ---> CP2 is a generic projection.Denote by Sj the branch curve of f01Wj: Wj---~ ~p2, j = 1,2, by Sj' the corresponding ramification curve in Wj, and by T the image of f0(WlrnW2). In the case of generic projection, St, $2 are cuspidal curves and T is a nodal curve. At the same time, the arrangement SI~S2uT in ~p2 is quite non-trivial already in simple cases, because there are many points of tangency in (SI~AS2)uT. Each of them comes from an intersection point of Sj'n(WlnW2) in V 0.Considering S as a regeneration of S1uS2kJr (or of "S1+$2+2T"), one can see that all cusps of S actually come from two sources: either from "old" cusps of S 1 and S 2, or from the tangency points mentioned above.An explicit analysis shows that "new" cusps come in triples. These geometrical considerations bring up, in particular, an interesting property of cuspidal branch curves, namely, that the number of cusps is divisible by three. When observing this fact, it is easy to prove it.Let us set:~p2 a stable ramified covering of ~p2, S the branch curve of f, S' the corresponding ramification curve in V (S' is a desingulari...