University of Stuttgart

About: University of Stuttgart is a education organization based out in Stuttgart, Germany. It is known for research contribution in the topics: Laser & Finite element method. The organization has 27715 authors who have published 56370 publications receiving 1363382 citations. The organization is also known as: Universität Stuttgart.

Intrinsic Atomic Orbitals: An Unbiased Bridge between Quantum Theory and Chemical Concepts.

Abstract: Modern quantum chemistry can make quantitative predictions on an immense array of chemical systems. However, the interpretation of those predictions is often complicated by the complex wave function expansions used. Here we show that an exceptionally simple algebraic construction allows for defining atomic core and valence orbitals, polarized by the molecular environment, which can exactly represent self-consistent field wave functions. This construction provides an unbiased and direct connection between quantum chemistry and empirical chemical concepts, and can be used, for example, to calculate the nature of bonding in molecules, in chemical terms, from first principles. In particular, we find consistency with electronegativities (χ), C 1s core-level shifts, resonance substituent parameters (σR), Lewis structures, and oxidation states of transition-metal complexes.

Quantum measurement and orientation tracking of fluorescent nanodiamonds inside living cells

Abstract: Fluorescent particles are routinely used to probe biological processes1. The quantum properties of single spins within fluorescent particles have been explored in the field of nanoscale magnetometry2,3,4,5,6,7,8, but not yet in biological environments. Here, we demonstrate optically detected magnetic resonance of individual fluorescent nanodiamond nitrogen-vacancy centres inside living human HeLa cells, and measure their location, orientation, spin levels and spin coherence times with nanoscale precision. Quantum coherence was measured through Rabi and spin-echo sequences over long (>10 h) periods, and orientation was tracked with effective 1° angular precision over acquisition times of 89 ms. The quantum spin levels served as fingerprints, allowing individual centres with identical fluorescence to be identified and tracked simultaneously. Furthermore, monitoring decoherence rates in response to changes in the local environment may provide new information about intracellular processes. The experiments reported here demonstrate the viability of controlled single spin probes for nanomagnetometry in biological systems, opening up a host of new possibilities for quantum-based imaging in the life sciences. The orientation, spin coherence times and spin energy levels of individual nanodiamond nitrogen-vacancy centres have been measured inside living human cells with nanoscale precision.

Canonical form observer design for non-linear time-variable systems

Abstract: An observer of canonical (phase-variable) form for non-linear time-variable systems is introduced. The development of this non-linear time-variable form requires regularity of the non-linear time-variable- observability matrix of the system. From the relationships derived during the development, it follows that a non-linear time-variable observer can be dimensioned by an eigenvalue assignment with respect to the canonical state coordinates if a linearization of system non-linearities about the reconstructed state trajectories is permissible. This is an assumption similar to that of the extended Kalman filter based on a linearization about the current estimate.

The making of bispecific antibodies

Abstract: During the past two decades we have seen a phenomenal evolution of bispecific antibodies for therapeutic applications. The ‘zoo’ of bispecific antibodies is populated by many different species, comprising around 100 different formats, including small molecules composed solely of the antigen-binding sites of two antibodies, molecules with an IgG structure, and large complex molecules composed of different antigen-binding moieties often combined with dimerization modules. The application of sophisticated molecular design and genetic engineering has solved many of the technical problems associated with the formation of bispecific antibodies such as stability, solubility and other parameters that confer drug properties. These parameters may be summarized under the term ‘developability’. In addition, different ‘target product profiles’, i.e., desired features of the bispecific antibody to be generated, mandates the need for access to a diverse panel of formats. These may vary in size, arrangement, vale...