The Chemistry of Cyborgs—Interfacing Technical Devices with Organisms

The term “cyborg” refers to a cybernetic organism, which characterizes the chimera of a living organism and a machine. Owing to the widespread application of intracorporeal medical devices, cyborgs are no longer exclusively a subject of science fiction novels, but technically they already exist in our society. In this review, we briefly summarize the development of modern prosthetics and the evolution of brain–machine interfaces, and discuss the latest technical developments of implantable devices, in particular, biocompatible integrated electronics and microfluidics used for communication and control of living organisms. Recent examples of animal cyborgs and their relevance to fundamental and applied biomedical research and bioethics in this novel and exciting field at the crossroads of chemistry, biomedicine, and the engineering sciences are presented.     

Molecular damage in bi-isonicotinic acid adsorbed on rutile TiO2(1 1 0)

Here we present the characteristic signatures in X-ray absorption and photoemission spectroscopy for molecular damage in adsorbed monolayers of bi-isonicotinic acid on a rutile TiO₂(1 1 0) surface. Bi-isonicotinic acid is the anchor ligand through which many important inorganic complexes are bound to the surface of TiO₂ in dye-sensitized solar cells. The nature of the damage caused by excessive heating of the adsorbed monolayer is consistent with splitting the molecule into two adsorbed isonicotinic acid molecular fragments. The effect on the lowest unoccupied molecular orbitals (involved in electron transfer in the molecule) can be understood in terms of the adsorption geometry of the reaction products and their nearest neighbor interactions.     

A convergent approach toward phoslactomycins and leustroducsins

Synthetic studies devoted to the development of a convergent approach toward phoslactomycins and leustroducsins, a family of natural products inhibitors of serine/threonine phosphatase 2A, are reported. A formal synthesis of phoslactomycin B was achieved in which the key steps are a [2,3]-Wittig rearrangement to control the C4 and C5 stereocenters, a diastereoselective addition of an acetylenic Grignard reagent to an α-alkoxy ketone to create the C8 tertiary alcohol, and a relay ring-closing metathesis to construct the α,β-unsaturated δ-lactone. In this approach, all the stereocenters originate, either directly or indirectly, from catalytic enantioselective reductions of acetylenic ketones.     

Material parameter computation for multi-layered vocal fold models

Today, the prevention and treatment of voice disorders is an ever-increasing health concern. Since many occupations rely on verbal communication, vocal health is necessary just to maintain one's livelihood. Commonly applied models to study vocal fold vibrations and air flow distributions are self sustained physical models of the larynx composed of artificial silicone vocal folds. Choosing appropriate mechanical parameters for these vocal fold models while considering simplifications due to manufacturing restrictions is difficult but crucial for achieving realistic behavior. In the present work, a combination of experimental and numerical approaches to compute material parameters for synthetic vocal fold models is presented. The material parameters are derived from deformation behaviors of excised human larynges. The resulting deformations are used as reference displacements for a tracking functional to be optimized. Material optimization was applied to three-dimensional vocal fold models based on isotropic and transverse-isotropic material laws, considering both a layered model with homogeneous material properties on each layer and an inhomogeneous model. The best results exhibited a transversal-isotropic inhomogeneous (i.e., not producible) model. For the homogeneous model (three layers), the transversal-isotropic material parameters were also computed for each layer yielding deformations similar to the measured human vocal fold deformations.     

Taming multiparticle entanglement

We present an approach to characterize genuine multiparticle entanglement by using appropriate approximations in the space of quantum states. This leads to a criterion for entanglement which can easily be calculated by using semidefinite programing and improves all existing approaches significantly. Experimentally, it can also be evaluated when only some observables are measured. Furthermore, it results in a computable entanglement monotone for genuine multiparticle entanglement. Based on this, we develop an analytical approach for the entanglement detection in cluster states, leading to an exponential improvement compared with existing schemes.