A5069252116- Nuclear materials and radiation effects
- Advanced Fluorescence Microscopy Techniques
- Recycling and utilization of industrial and municipal waste in materials production
- Graphite, nuclear technology, radiation studies
- Glass properties and applications
- Nuclear and radioactivity studies
- Fiber-reinforced polymer composites
- Photoreceptor and optogenetics research
- Recycling and Waste Management Techniques
- Geophysical Methods and Applications
- Advanced Electron Microscopy Techniques and Applications
- Nuclear Materials and Properties
- Radiative Heat Transfer Studies
- Bacterial Genetics and Biotechnology
- Neural dynamics and brain function
- X-ray Spectroscopy and Fluorescence Analysis
- Polymer Science and PVC
- Near-Field Optical Microscopy
- Thermal properties of materials
- Bacteriophages and microbial interactions
- Receptor Mechanisms and Signaling
- Material Properties and Applications
- Photosynthetic Processes and Mechanisms
- Digital Holography and Microscopy
- Protein Structure and Dynamics
Max Planck Institute for the Science of Light
2013-2025
Friedrich-Alexander-Universität Erlangen-Nürnberg
2014-2025
Karlsruhe Institute of Technology
1972-2023
Rockefeller University
2017-2019
Research Institute of Molecular Pathology
2016-2017
Max Perutz Labs
2017
University of Vienna
2017
Max Planck Society
2013
Max Planck Institute for Solid State Research
2011
University of Stuttgart
2011
We investigate the role of electron−hole correlations in absorption free-standing monolayer and bilayer graphene using optical transmission spectroscopy from 1.5 to 5.5 eV. Line shape analysis demonstrates that ultraviolet region is dominated by an asymmetric Fano resonance. attribute this excitonic resonance forms near van Hove singularity at saddle point band structure couples Dirac continuum. The model quantitatively describes experimental data all way down infrared. In contrast, common...
Abstract G protein–coupled receptors (GPCRs), including dopamine receptors, represent a group of important pharmacological targets. An increased formation receptor D 2 homodimers has been suggested to be associated with the pathophysiology schizophrenia. Selective labeling and ligand-induced modulation dimerization may therefore allow investigation pathophysiological role these dimers. Using TIRF microscopy at single molecule level, transient in membrane stably transfected CHO cells...
The optical microscope is one of the oldest scientific instruments that still used in forefront research. Ernst Abbe’s nineteenth century formulation resolution limit microscopy let generations scientists believe studies individual molecules and resolving subwavelength structures were not feasible. Nobel Prize 2014 for super-resolution fluorescence marks a clear recognition old beliefs have to be revisited. In this article, we present critical overview various recent developments microscopy....
Abstract The main limiting factor in spatial resolution of localization microscopy is the number detected photons. Recently we showed that cryogenic measurements improve photostability fluorophores, giving access to Angstrom precision single molecules. Here, extend this method colocalize two fluorophores attached well‐defined positions a double‐stranded DNA. By measuring separations fluorophore pairs prepared at different design positions, verify feasibility distance measurement with...
Abstract Membrane bound histidine kinases (HKs) are ubiquitous sensors of extracellular stimuli in bacteria. However, a uniform structural model is still missing for their transmembrane signaling mechanism. Here, we used solid-state NMR conjunction with crystallography, solution and distance measurements to investigate the mechanism paradigmatic citrate sensing membrane embedded HK, CitA. Citrate binding sensory extracytoplasmic PAS domain (PASp) causes linker helix 2 (TM2) adopt helical...
The precision in localizing a molecule is ultimately determined by the number of detected photons, which turn limited photobleaching. Currently, fluorophores can be routinely localized to few tens nanometers at room temperature. In this work we demonstrate localization better than 3 Angstrom substantial improvement molecular photostability cryogenic temperatures. We discuss challenges, solutions and promise our methodology for high-performance co-localization super-resolution microscopy.
We perform X-ray absorption fine structure (XAFS) spectroscopy measurements at the sulfur K-edge to elucidate electronic and geometric bonding of atoms in borosilicate glass used for vitrification high level radioactive liquid waste. The is incorporated as sulfate, most probably sodium which can be deduced from near edge (XANES) by fingerprint comparison with reference compounds. This finding backed up Raman investigation. In extended XAFS data, no second shell beyond first oxygen layer...
Abstract Considerable efforts are currently being devoted to enhance the speed, spatial resolution and size of 3D sample volumes in which calcium imaging methods can capture neuronal network activity different model systems. In mammalian brain, tissue scattering severely limits use parallel acquisition techniques such as wide-field and, a consequence, based on two-photon point-scanning (2PM) have become method choice. However, 2PM faces severe restrictions due technical limitations scan...
ABSTRACT The plethora of available scientific cameras different types challenges the biologically oriented experimenter when picking appropriate camera for his experiment. In this study, we chose to investigate performances in a typical nonsingle molecule situation life sciences, that is, quantitative measurements fluorescence intensity changes from video data with typically skewed distributions. Here, profile dynamics pH‐sensors upon triggered pH‐environments living cells served as model...
Abstract Membrane bound histidine kinases (HKs) are ubiquitous sensors of extracellular stimuli in bacteria. Here, we used solid-state NMR conjunction with crystallography, solution and distance measurements to investigate the transmembrane signaling mechanism a paradigmatic citrate sensing membrane embedded HK, CitA. Citrate binding sensory extracytoplasmic PAS domain (PASp) causes linker helix 2 (TM2) adopt helical conformation. This triggers piston-like pulling TM2 quaternary structure...
The Rokkasho Reprocessing Plant, located in northern Japan, includes facilities for reprocessing spent nuclear fuels and immobilizing high-level waste (HLW) into a stable-glass form based on borosilicate. vitrification process consists of two large liquid-fed, joule-heated, ceramic-lined melters (LFCMs). During the active test campaigns at Vitrification Facility, unstable melting performance difficulty glass operation were observed LFCM operation. operating protocols that had been developed...
High level waste (HLW) originating from reprocessing of spent fuel commercial power reactors contains more than 40 different elements. Vitrification into borosilicate glass at 1100 ∼1200°C is the process choice. It routinely used to immobilize radioactive constituents in a chemically stable matrix for final geological disposal. Melting HLW glasses are variants two basic designs. (1) The joule-heated ceramic-lined melter (JHCM) originally developed United States 1973 and several nuclear sites...
Vitrification of high-level liquid waste from the nuclear fuel cycle in a liquid-fed electric glass melter is described with particular reference to present status technology developed at Institut für Nukleare Entsorgungstechnik (INE), Karlsruhe, West Germany. Application process an active plant be built Eurochemic Site Mol, Belgium, outlined. Based on available experience simulated solutions, it shown that melting promising technique can substantially simplify vitrification.
As a part of major AGARD project concerning thermophysical properties solid materials at high temperatures, cooperative thermal expansion measurements up to 1000°C were carried out using pushrod techniques. Sixteen laboratories have contributed results. Parallel samples having the same history used for all tests. Materials investigated very pure gold and platinum, an austenitic alloy, alumina, three types graphite. From mean values individual contributors, band widths group scatter as well...