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Stuttgart, Germany

The University of Stuttgart is a university located in Stuttgart, Germany. It was founded in 1829 and is organized in 10 faculties.It is one of the top nine leading technical universities in Germany with highly ranked programs in civil, mechanical, industrial and electrical engineering.The University of Stuttgart is especially known for its excellent reputation in the fields of advanced automotive engineering, efficient industrial and automated manufacturing, process engineering, aerospace engineering and activity-based costing. The academic tradition of the University of Stuttgart goes back to its probably most famous graduate student: Gottlieb Daimler, the Inventor of the automobile.Along with the Technical University of Munich, the Technical University of Darmstadt and Karlsruhe Institute of Technology, it represents one of the four members of the South German Axis of Advanced Engineering and Management. These four universities, in combination with RWTH Aachen are the top five universities of the aforementioned TU9. Wikipedia.

Seifert U.,University of Stuttgart
Reports on Progress in Physics

Stochastic thermodynamics as reviewed here systematically provides a framework for extending the notions of classical thermodynamics such as work, heat and entropy production to the level of individual trajectories of well-defined non-equilibrium ensembles. It applies whenever a non-equilibrium process is still coupled to one (or several) heat bath(s) of constant temperature. Paradigmatic systems are single colloidal particles in time-dependent laser traps, polymers in external flow, enzymes and molecular motors in single molecule assays, small biochemical networks and thermoelectric devices involving single electron transport. For such systems, a first-law like energy balance can be identified along fluctuating trajectories. For a basic Markovian dynamics implemented either on the continuum level with Langevin equations or on a discrete set of states as a master equation, thermodynamic consistency imposes a local-detailed balance constraint on noise and rates, respectively. Various integral and detailed fluctuation theorems, which are derived here in a unifying approach from one master theorem, constrain the probability distributions for work, heat and entropy production depending on the nature of the system and the choice of non-equilibrium conditions. For non-equilibrium steady states, particularly strong results hold like a generalized fluctuation-dissipation theorem involving entropy production. Ramifications and applications of these concepts include optimal driving between specified states in finite time, the role of measurement-based feedback processes and the relation between dissipation and irreversibility. Efficiency and, in particular, efficiency at maximum power can be discussed systematically beyond the linear response regime for two classes of molecular machines, isothermal ones such as molecular motors, and heat engines such as thermoelectric devices, using a common framework based on a cycle decomposition of entropy production. © 2012 IOP Publishing Ltd. Source

Seifert U.,University of Stuttgart
Physical Review Letters

We consider nanosized artificial or biological machines working in steady state enforced by imposing nonequilibrium concentrations of solutes or by applying external forces, torques, or electric fields. For unicyclic and strongly coupled multicyclic machines, efficiency at maximum power is not bounded by the linear response value 1/2. For strong driving, it can even approach the thermodynamic limit 1. Quite generally, such machines fall into three different classes characterized, respectively, as "strong and efficient," "strong and inefficient," and "balanced." For weakly coupled multicyclic machines, efficiency at maximum power has lost any universality even in the linear response regime. © 2011 The American Physical Society. Source

Jeltsch A.,University of Stuttgart
Trends in Biochemical Sciences

After approximately 3 billion years of unicellular life on Earth, multicellular animals appeared some 600 million years ago, followed by the rapid emergence of most animal phyla during the Cambrian radiation. This evolutionary jump was paralleled by an increase in atmospheric oxygen, which I propose allowed the generation of epigenetic signaling systems that are essential for cellular differentiation in animals. Epigenetic signaling is based on the reversible deposition of chemically stable marks in DNA and histone proteins, with methylation of cytosine and lysine residues, respectively, playing a central role. Recent evidence indicates that the removal of such methyl groups critically depends on oxygenases. Hence, reversible epigenetic systems could only appear after accumulation of oxygen in the atmosphere. © 2013 Elsevier Ltd. Source

University of Stuttgart | Date: 2013-04-04

An exhaust gas system for an internal combustion engine includes at least one first and one second exhaust gas connection interface for fluidically separated discharge of exhaust gas arising during a combustion process from a combustion chamber of the internal combustion engine, and one at least dual-pipe exhaust gas turbocharger having at least one first and one second supply connection interface for fluidically separated supply of the exhaust gases arising during the combustion process, wherein a first connecting channel is designed for fluidic connection of the first exhaust gas connection interface to the first supply connection interface, and a second connecting channel is designed for fluidic connection of the second exhaust gas connection interface to the second supply connection interface. At least one of the connecting channels is designed to be at least partially closable by a closure element.

Disclosed are methods and an assembly for robust one-shot interferometry, in particular for optical coherence tomography according to the spatial domain approach (SD-OCT) and/or according to the light-field approach. In one embodiment, the method and the assembly may be used for measurements on material and living tissue, for distance measurement, for 2D or 3D measurement with a finely structured light source imaged onto the object in a diffraction-limited way, or with spots thereof. The assembly may comprise an interferometer having object and reference arms and a detector for electromagnetic radiation. In other embodiments, during a detection process, a plurality of spatial interferograms may be formed by making an inclined and/or curved reference wavefront interfere with an object wavefront for each measurement point. The resulting spatial interferograms may be detected in a single detector frame and may be further evaluated via a computer program.

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