Novel Intermediate Filament Proteins in Ramazzottius varieornatus and Todarodes pacificus

Tardigrades are an extremophile invertebrate phylum increasingly popular in astrobiological research and science journalism on account of their extreme resilience. Ramazzottius varieornatus possesses three intermediate filament proteins; orthologs of an A-type lamin 2, a B-type lamin 1 and a cytoplasmic intermediate filament called cytotardin found in H. dujardini. This project aims to investigate to what extent the molecular similarities between the novel cytoplasmic intermediate filament and its lamin counterparts leads to similar in vitro properties. To this end, this protein, mutants thereof and a novel eye lens intermediate filament protein in Todarodes pacificus possessing molecular structural similarities to the tardigrade proteins, were produced and examined. Sequence and simulated biochemical analysis, as well as the nature of the rapid in vitro assembly of multiple superstructures indicates the lamin-like behaviour of the tardigrade cytoplasmic intermediate filament, whose central rod domain has the proportions of a Type V intermediate filament. Cytotardin is shown by electron microscopy, quantified by sedimentation assay, to be able to form paracrystalline structures across a wide range of pH and ionic strengths with a 24-25nm banding pattern characteristic of lamins. Substitution of an α-helix arginine residue for cysteine in the conserved LNTR motif mimics the keratin-14 mutation first associated with Epidermolysis Bullosa, causing partial loss of function. Deletion of the tail segment of cytotardin removes the ability to form sustainable paracrystals, let alone do so without divalent cations, supporting current models for intermediate filament assembly. Cytotardin and the A-type lamin appear closely related, based on their sequence identity and Western blot analysis and are capable of forming complex paracrystals with mobile structures. The in vitro networks of cytotardin and the A-Type lamin create viscous reticuli and gels in the solutions they inhabit. Western blot analysis shows both cytotardin and to a lesser extent the two R. varieornatus lamins are recognised by rabbit serum antibodies against T. pacificus eye lens protein

Electric field gradient calculations for LixTiS2 and comparison with 7Li NMR results

The elements of the electric field gradient tensor at Li position in the intercalation compound LixTiS2 (with x=0.25, 0.33, 0.67, and 1.0) were calculated with first-principles methods and periodic supercell models. The theoretical results obtained with density functional and Hartree-Fock hybrid methods were compared with experimental field gradients extracted from 7Li NMR spectra from the literature and from our measurements presented here. The dependence of calculated field gradients on the basis set and the explicit form of the exchange-correlation density functional was investigated. In agreement with earlier studies a pronounced effect of polarization functions at the Li site was observed. After optimization of internal degrees of freedom in LiTiS2 all methods under consideration give quadrupole coupling constants in close agreement with experiment. For x < 1 the calculated quadrupole coupling constants were found to depend more sensitively on the method which was attributed to differences in the description of spin localization. The calculations allow one to distinguish between Li atoms placed at octahedral and tetrahedral interstitial sites of the host lattice TiS2. © 2004 American Physical Societ

Beliefs and attitudes of citizens in Germany towards smart surveillance and privacy

This document presents the German results of a qualitative study undertaken as part of the SMART project – “Scalable Measures for Automated Recognition Technologies” (SMART; G.A. 261727). The analysis and results are based on a set of three focus group discussions comprising of 22 participants, which were held in order to examine the beliefs and attitudes of citizens towards smart surveillance and privacy. The focus group discussions were conducted in line with a discussion guide mainly consisting of different scenarios aimed at stimulating a discussion amongst the participants. While some scenarios dealt with surveillance in everyday contexts likely to be encountered by research participants, other scenarios were hypothetical in nature and their aim was to elicit the feelings, beliefs and attitudes of the participants in relation to dataveillance, the massive integration of data from different sources, and the “security versus privacy trade-off”.Scalable Measures for Automated Recognition Technologies (G.A. 267127). The project was co-financed by the European Union within the Seventh Framework Programme (2007-2013).peer-reviewe

Synthesis of ternary transition metal fluorides Li 3MF 6via a sol-gel route as candidates for cathode materials in lithium-ion batteries

A sol-gel route for ternary lithium fluorides of transition metals (M) is presented allowing the synthesis of Li 3MF 6-type and Li 2MF 5-type compounds. It is based on a fluorolytic process using transition metal acetylacetonates as precursors. The domain size of the obtained powders can be controlled by modifying the conditions of synthesis. 6Li and 7Li magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy is used to study local environments of the Li ions in orthorhombic and monoclinic Li 3VF 6 as well as Li 2MnF 5. The number of magnetically inequivalent Li sites found by MAS NMR is in agreement with the respective crystal structure of the compounds studied. Quantum chemical calculations show that all materials have high de-lithiation energies making them suitable candidates to be used as high-voltage battery cathode materials. © 2012 The Royal Society of Chemistry

The role of local and remote amino acid substitutions for optimizing fluorescence in bacteriophytochromes: A case study on iRFP

Bacteriophytochromes are promising tools for tissue microscopy and imaging due to their fluorescence in the near-infrared region. These applications require optimization of the originally low fluorescence quantum yields via genetic engineering. Factors that favour fluorescence over other non-radiative excited state decay channels are yet poorly understood. In this work we employed resonance Raman and fluorescence spectroscopy to analyse the consequences of multiple amino acid substitutions on fluorescence of the iRFP713 benchmark protein. Two groups of mutations distinguishing iRFP from its precursor, the PAS-GAF domain of the bacteriophytochrome P2 from Rhodopseudomonas palustris, have qualitatively different effects on the biliverdin cofactor, which exists in a fluorescent (state II) and a non-fluorescent conformer (state I). Substitution of three critical amino acids in the chromophore binding pocket increases the intrinsic fluorescence quantum yield of state II from 1.7 to 5.0% due to slight structural changes of the tetrapyrrole chromophore. Whereas these changes are accompanied by an enrichment of state II from ~40 to ~50%, a major shift to ~88% is achieved by remote amino acid substitutions. Additionally, an increase of the intrinsic fluorescence quantum yield of this conformer by ~34% is achieved. The present results have important implications for future design strategies of biofluorophores.DFG, 221545957, SFB 1078: Proteinfunktion durch ProtonierungsdynamikDFG, 53182490, EXC 314: Unifying Concepts in Catalysi

Unravelling ultraslow lithium-ion diffusion in γ-LiAlO2 : experiments with tracers, neutrons, and charge carriers

Lithium aluminum oxide (γ-LiAlO2) has been discussed and used for various applications, e.g., as electrode coating, membrane, or tritium breeder material. Although lithium-ion diffusion in this solid is essential for these purposes, it is still not sufficiently understood on the microscopic scale. Herein, we not only summarize and assess the available studies on diffusion in different crystalline forms of γ-LiAlO2, but also complement them with tracer-diffusion experiments on (001)- and conductivity spectroscopy on (100)-oriented single crystals, yielding activation energies of 1.20(5) and 1.12(1) eV, respectively. Scrutinous crystal-chemical considerations, Voronoi–Dirichlet partitioning, and Hirshfeld surface analysis are employed to identify possible diffusion pathways. The one-particle potential, as derived from high-temperature powder neutron diffraction data presented as well, reveals the major path to be strongly curved and to run between adjacent lithium positions with a migration barrier of 0.72(5) eV. This finding is substantiated by comparison with recently published computational results. For the first time, a complete model for lithium-ion diffusion in γ-LiAlO2, consistent with all available data, is presented.DFG, FOR 1277, Mobilität von Lithiumionen in Festkörpern (molife

“A very orderly retreat”: Democratic transition in East Germany, 1989-90

East Germany's 1989-90 democratisation is among the best known of East European transitions, but does not lend itself to comparative analysis, due to the singular way in which political reform and democratic consolidation were subsumed by Germany's unification process. Yet aspects of East Germany's democratisation have proved amenable to comparative approaches. This article reviews the comparative literature that refers to East Germany, and finds a schism between those who designate East Germany's transition “regime collapse” and others who contend that it exemplifies “transition through extrication”. It inquires into the merits of each position and finds in favour of the latter. Drawing on primary and secondary literature, as well as archival and interview sources, it portrays a communist elite that was, to a large extent, prepared to adapt to changing circumstances and capable of learning from “reference states” such as Poland. Although East Germany was the Soviet state in which the positions of existing elites were most threatened by democratic transition, here too a surprising number succeeded in maintaining their position while filing across the bridge to market society. A concluding section outlines the alchemy through which their bureaucratic power was transmuted into property and influence in the “new Germany”

An efficient numerical method for solving the Boltzmann equation in multidimensions

International audienceIn this paper we deal with the extension of the Fast Kinetic Scheme (FKS) [J. Comput. Phys., Vol. 255, 2013, pp 680-698] originally constructed for solving the BGK equation, to the more challenging case of the Boltzmann equation. The scheme combines a robust and fast method for treating the transport part based on an innovative Lagrangian technique supplemented with fast spectral schemes to treat the collisional operator by means of an operator splitting approach. This approach along with several implementation features related to the parallelization of the algorithm permits to construct an efficient simulation tool which is numerically tested against exact and reference solutions on classical problems arising in rarefied gas dynamic. We present results up to the 3D×3D case for unsteady flows for the Variable Hard Sphere model which may serve as benchmark for future comparisons between different numerical methods for solving the multidimensional Boltzmann equation. For this reason, we also provide for each problem studied details on the computational cost and memory consumption as well as comparisons with the BGK model or the limit model of compressible Euler equations