Resolution of the Chiral (1 R,2S) Enantiomer of cis-Cyclohexane-1,2-dicarboxylic Acid in the Brucinium Salt 2,3-Dimethoxy-10-oxostrychnidinium (1 R,2S)-2-carboxycyclohexane-1-carboxylate Dihydrate

The structure of the 1:1 brucinium salt of cis-cyclohexane-1,2-dicarboxylic acid, 2,3-dimethoxy-10-oxostrychnidinium (1R,2S)-2-carboxycyclohexane-1-carboxylate dihydrate, has revealed the resolved (1R,2S) enantiomer of the acid. Crystals of the compound are orthorhombic, space group P212121, with unit cell dimensions a = 8.1955(3), b = 12.4034(3), c = 29.9073(9)Å, and Z = 4. The asymmetric unit comprises the brucinium cation, the hydrogen cis-cyclohexane-1,2-dicarboxylate cation, in which the carboxylate group is disordered over two sites (58, 42%), and two water molecules of solvation, one of which is occupies two 50% occupancy sites. The classic undulating brucinium cation substructures are present with the anion and the water molecules occupying the interstitial cavities and are hydrogen-bonded to them in a two-dimensional network structure

Toward higher-performance bionic limbs for wider clinical use

Funding Information: We were supported by the Academy of Finland (I.V.), Austrian Federal Ministry of Science (A.S. and O.C.A.), Bertarelli Foundation (S.M.), the European Union (A.S., D.F., K.-P.H., O.C.A., R.B. and S.M.), the European Research Council (A.S., D.F. and O.C.A.), German Federal Ministry of Education and Research BMBF (K.-P.H. and T.S.), the German National Research Foundation (T.S.), the Royal British Legion (A.M.J.B.), the Swedish Innovation Agency (VINNOVA) (R.B.), the Swedish Research Council (R.B.), the Swiss National Competence Center in Research (NCCR) in Robotics (S.M.), US Department of Defense (R.B. and H.H.), US Department of Veterans Affairs (D.T.), US Department of Veterans Affairs Rehabilitation Research and Development Service (R.F.ff.W.), US National Institute on Disability, Independent Living and Rehabilitation Research (H.H. and T.K.), US National Institutes of Health (D.T., H.H., L.J.H. and R.F.ff.W.), US National Institute on Neurological Disorders and Stroke (R.F.ff.W.), USNational Institute on Bioimaging and Bioengineering (R.F.ff.W.) and US National Science Foundation (H.H.). Publisher Copyright: © 2021, Springer Nature Limited.Most prosthetic limbs can autonomously move with dexterity, yet they are not perceived by the user as belonging to their own body. Robotic limbs can convey information about the environment with higher precision than biological limbs, but their actual performance is substantially limited by current technologies for the interfacing of the robotic devices with the body and for transferring motor and sensory information bidirectionally between the prosthesis and the user. In this Perspective, we argue that direct skeletal attachment of bionic devices via osseointegration, the amplification of neural signals by targeted muscle innervation, improved prosthesis control via implanted muscle sensors and advanced algorithms, and the provision of sensory feedback by means of electrodes implanted in peripheral nerves, should all be leveraged towards the creation of a new generation of high-performance bionic limbs. These technologies have been clinically tested in humans, and alongside mechanical redesigns and adequate rehabilitation training should facilitate the wider clinical use of bionic limbs.Peer reviewe