Institution
University of Konstanz
Education•Konstanz, Baden-Württemberg, Germany•
About: University of Konstanz is a education organization based out in Konstanz, Baden-Württemberg, Germany. It is known for research contribution in the topics: Population & Membrane. The organization has 12115 authors who have published 27401 publications receiving 951162 citations. The organization is also known as: University of Constance & Universität Konstanz.
Topics: Population, Membrane, Politics, Laser, Gene
Papers published on a yearly basis
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TL;DR: This study provides experimental and theoretical evidence for a simple mechanism to explain the emergence of collective behavior from consistent individual differences, including variation in the structure, leadership, movement dynamics, and functional capabilities of groups, across social and ecological scales.
252 citations
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TL;DR: The dissociation rate constant is equal to 2 sec−1, a value which is consistent with the channel lifetime as obtained from electrical fluctuation measurements, and which is by three orders of magnitude below the limiting value of a diffusion-controlled reaction in a two-dimensional system.
Abstract: Previous studies have given evidence that the active form of gramicidin A in lipid bilayer membranes is a dimer which acts as an ion channel; it has been further shown that the mean lifetime of the channel strongly depends on the membrane thickness. As the thickness slightly decreases when a voltage is applied to the membrane, the equilibrium between conducting dimers and nonconducting monomers may be displaced by a voltage jump. From the relaxation of the electrical current after the voltage jump, information about the kinetics of channel formation is obtained. For a dioleoyllecithin/n-decane membrane the rate constant of association is found to be 2×1014 cm2 mole−1 sec−1, which is by three orders of magnitude below the limiting value of a diffusion-controlled reaction in a two-dimensional system. The dissociation rate constant is equal to 2 sec−1, a value which is consistent with the channel lifetime as obtained from electrical fluctuation measurements.
252 citations
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University of Konstanz1, South Valley University2, Technical University of Dortmund3, Leiden University4, Innsbruck Medical University5, Vrije Universiteit Brussel6, Federal Institute for Risk Assessment7, University of Mainz8, French Institute for Research in Computer Science and Automation9, University of Paris10, Leipzig University11, University of Tübingen12, Johns Hopkins University13, Heidelberg University14, Leiden University Medical Center15, Pompeu Fabra University16, Karolinska Institutet17, Stockholm University18, Mario Negri Institute for Pharmacological Research19, University of Vienna20, European Food Safety Authority21, VU University Amsterdam22, Maastricht University23, OpenPHACTS24, Paris Diderot University25, University of Copenhagen26, Istituto Superiore di Sanità27, Fraunhofer Society28
TL;DR: The history of the AOP concept and its most prominent strengths are discussed, including the advantages of a formalized approach, the systematic collection of weight of evidence, the linkage of mechanisms to apical end points, the examination of the plausibility of epidemiological data, the identification of critical knowledge gaps and the design of mechanistic test methods.
Abstract: Adverse outcome pathways (AOPs) are a recent toxicological construct that connects, in a formalized, transparent and quality-controlled way, mechanistic information to apical endpoints for regulatory purposes. AOP links a molecular initiating event (MIE) to the adverse outcome (AO) via key events (KE), in a way specified by key event relationships (KER). Although this approach to formalize mechanistic toxicological information only started in 2010, over 200 AOPs have already been established. At this stage, new requirements arise, such as the need for harmonization and re-assessment, for continuous updating, as well as for alerting about pitfalls, misuses and limits of applicability. In this review, the history of the AOP concept and its most prominent strengths are discussed, including the advantages of a formalized approach, the systematic collection of weight of evidence, the linkage of mechanisms to apical end points, the examination of the plausibility of epidemiological data, the identification of critical knowledge gaps and the design of mechanistic test methods. To prepare the ground for a broadened and appropriate use of AOPs, some widespread misconceptions are explained. Moreover, potential weaknesses and shortcomings of the current AOP rule set are addressed (1) to facilitate the discussion on its further evolution and (2) to better define appropriate vs. less suitable application areas. Exemplary toxicological studies are presented to discuss the linearity assumptions of AOP, the management of event modifiers and compensatory mechanisms, and whether a separation of toxicodynamics from toxicokinetics including metabolism is possible in the framework of pathway plasticity. Suggestions on how to compromise between different needs of AOP stakeholders have been added. A clear definition of open questions and limitations is provided to encourage further progress in the field.
251 citations
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TL;DR: It is shown that reggie-1 is myristoylated and multiply palmitoylation and that lipid modifications are necessary for membrane association of reggie -1, suggesting a role for reggies-1 as a signalling protein in actin-dependent processes.
Abstract: The reggie protein family consists of two proteins, reggie-1 and -2, also called flotillins, which are highly ubiquitous and evolutionarily conserved. Both reggies have been shown to be associated with membrane rafts and are involved in various cellular processes such as T-cell activation, phagocytosis and insulin signalling. However, the exact molecular function of these proteins remains to be determined. In addition, the mechanism of membrane association of reggie-1, which does not contain any transmembrane domain, is not known. In this study, we have produced a fusion protein of reggie-1 with enhanced green fluorescent protein and generated targeted substitutions for the inactivation of putative palmitoylation and myristoylation sites. We were able to show that reggie-1 is myristoylated and multiply palmitoylated and that lipid modifications are necessary for membrane association of reggie-1. Overexpression of reggie-1 resulted in the induction of numerous filopodia-like protrusions in various cell lines, suggesting a role for reggie-1 as a signalling protein in actin-dependent processes.
251 citations
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TL;DR: In this paper, transient ion-drift measurements were used to quantify activation energy, diffusion coefficient, and concentration of mobile ions in methylammonium lead triiodide (MAPbI3) perovskite solar cells, and find that their properties change close to the tetragonal-toorthorhombic phase transition temperature.
Abstract: Ion migration in halide perovskite films leads to device degradation and impedes large scale commercial applications. We use transient ion-drift measurements to quantify activation energy, diffusion coefficient, and concentration of mobile ions in methylammonium lead triiodide (MAPbI3) perovskite solar cells, and find that their properties change close to the tetragonal-to-orthorhombic phase transition temperature. We identify three migrating ion species which we attribute to the migration of iodide (I−) and methylammonium (MA+). We find that the concentration of mobile MA+ ions is one order of magnitude higher than the one of mobile I− ions, and that the diffusion coefficient of mobile MA+ ions is three orders of magnitude lower than the one for mobile I− ions in our samples. This quantification of mobile ions in MAPbI3 will lead to a better understanding of ion migration and its role in operation and degradation of perovskite solar cells.
251 citations
Authors
Showing all 12272 results
Name | H-index | Papers | Citations |
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Robert E. W. Hancock | 152 | 775 | 88481 |
Lloyd J. Old | 152 | 775 | 101377 |
Andrew White | 149 | 1494 | 113874 |
Stefanie Dimmeler | 147 | 574 | 81658 |
Rudolf Amann | 143 | 459 | 85525 |
Niels Birbaumer | 142 | 835 | 77853 |
Thomas P. Russell | 141 | 1012 | 80055 |
Emmanuelle Perez | 138 | 1550 | 99016 |
Shlomo Havlin | 131 | 1013 | 83347 |
Bruno S. Frey | 119 | 900 | 65368 |
Roald Hoffmann | 116 | 870 | 59470 |
Michael G. Fehlings | 116 | 1189 | 57003 |
Yves Van de Peer | 115 | 494 | 61479 |
Axel Meyer | 112 | 511 | 51195 |
Manuela Campanelli | 111 | 675 | 48563 |