Recent Submissions

  • Journal Article

    Branched flow and caustics in nonlinear waves 

    Green, Gerrit; Fleischmann, Ragnar
    New Journal of Physics 2019; 21(8): Art. 083020
    Rogue waves, i.e.high amplitude fluctuations in random wave fields, have been studied in several contexts, ranging from optics via acoustics to the propagation of ocean waves. Scattering by disorder, like current fields and wind fluctuations in the ocean, as well as nonlinearities in the wave equations provide widely studied mechanisms for their creation. However, the interaction of these mechanisms is largely unexplored. Hence, we study wave propagation under the concurrent influence of geometrical (disorder) and nonlinear focusing in the (current-modified) nonlinear Schrödinger equation.Weshow how nonlinearity shifts the onset distance of geometrical (disorder) focusing and alters the peak intensities of the fluctuations.Wefind an intricate interplay of both mechanisms that is reflected in the observation of optimal ratios of nonlinearity and disorder strength for the generation of rogue waves.
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  • Journal Article

    Nanoscale Mapping of Ultrafast Magnetization Dynamics with Femtosecond Lorentz Microscopy 

    Rubiano da Silva, Nara; Möller, Marcel; Feist, Armin; Ulrichs, Henning; Ropers, Claus; Schäfer, Sascha
    Physical Review X 2018; 8(3): Art. 031052
    Novel time-resolved imaging techniques for the investigation of ultrafast nanoscale magnetization dynamics are indispensable for further developments in light-controlled magnetism. Here, we introduce femtosecond Lorentz microscopy, achieving a spatial resolution below 100 nm and a temporal resolution of 700 fs, which gives access to the transiently excited state of the spin system on femtosecond timescales and its subsequent relaxation dynamics. We demonstrate the capabilities of this technique by spatiotemporally mapping the light-induced demagnetization of a single magnetic vortex structure and quantitatively extracting the evolution of the magnetization field after optical excitation. Tunable electron imaging conditions allow for an optimization of spatial resolution or field sensitivity, enabling future investigations of ultrafast internal dynamics of magnetic topological defects on a 10 nm length scale.
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  • Journal Article

    CaosDB—Research Data Management for Complex, Changing, and Automated Research Workflows 

    Fitschen, Timm; Schlemmer, Alexander; Hornung, Daniel; tom Wörden, Henrik; Parlitz, Ulrich; Luther, Stefan
    Data 2019; 4(2)
    We present CaosDB, a Research Data Management System (RDMS) designed to ensure seamless integration of inhomogeneous data sources and repositories of legacy data in a FAIR way. Its primary purpose is the management of data from biomedical sciences, both from simulations and experiments during the complete research data lifecycle. An RDMS for this domain faces particular challenges: research data arise in huge amounts, from a wide variety of sources, and traverse a highly branched path of further processing. To be accepted by its users, an RDMS must be built around workflows of the scientists and practices and thus support changes in workflow and data structure. Nevertheless, it should encourage and support the development and observation of standards and furthermore facilitate the automation of data acquisition and processing with specialized software. The storage data model of an RDMS must reflect these complexities with appropriate semantics and ontologies while offering simple methods for finding, retrieving, and understanding relevant data. We show how CaosDB responds to these challenges and give an overview of its data model, the CaosDB Server and its easy-to-learn CaosDB Query Language. We briefly discuss the status of the implementation, how we currently use CaosDB, and how we plan to use and extend it.
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  • Journal Article

    Topological Stabilization and Dynamics of Self-Propelling Nematic Shells 

    Hokmabad, Babak Vajdi; Baldwin, Kyle A.; Krüger, Carsten; Bahr, Christian; Maass, Corinna C.
    Physical Review Letters 2019; 123(17): Art. 178003
    Liquid shells (e.g., double emulsions, vesicles, etc.) are susceptible to interfacial instability and rupturing when driven out of mechanical equilibrium. This poses a significant challenge for the design of liquid-shell-based micromachines, where the goal is to maintain stability and dynamical control in combination with motility. Here, we present our solution to this problem with controllable self-propelling liquid shells, which we have stabilized using the soft topological constraints imposed by a nematogen oil. We demonstrate, through experiments and simulations, that anisotropic elasticity can counterbalance the destabilizing effect of viscous drag induced by shell motility and inhibit rupturing. We analyze their propulsion dynamics and identify a peculiar meandering behavior driven by a combination of topological and chemical spontaneously broken symmetries. Based on our understanding of these symmetry breaking mechanisms, we provide routes to control shell motion via topology, chemical signaling, and hydrodynamic interactions.
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  • Journal Article

    Predicting Spatio-temporal Time Series Using Dimension Reduced Local States 

    Isensee, Jonas; Datseris, George; Parlitz, Ulrich
    Journal of Nonlinear Science
    We present a method for both cross-estimation and iterated time series prediction of spatio-temporal dynamics based on local modelling and dimension reduction techniques. Assuming homogeneity of the underlying dynamics, we construct delay coordinates of local states and then further reduce their dimensionality through Principle Component Analysis. The prediction uses nearest neighbour methods in the space of dimension reduced states to either cross-estimate or iteratively predict the future of a given frame. The effectiveness of this approach is shown for (noisy) data from a (cubic) Barkley model, the Bueno-Orovio–Cherry–Fenton model, and the Kuramoto–Sivashinsky model.
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  • Journal Article

    Undesired Bulk Oxidation of LiMn2O4 Increases Overpotential of Electrocatalytic Water Oxidation in Lithium Hydroxide Electrolytes 

    Baumung, Max; Kollenbach, Leon; Xi, Lifei; Risch, Marcel
    ChemPhysChem(20) p.1-9
    Chemical and structural changes preceding electrocatalysis obfuscate the nature of the active state of electrocatalysts for the oxygen evolution reaction (OER), which calls for model systems to gain systematic insight. We investigated the effect of bulk oxidation on the overpotential of ink-casted LiMn2 O4 electrodes by a rotating ring-disk electrode (RRDE) setup and X-ray absorption spectroscopy (XAS) at the K shell core level of manganese ions (Mn-K edge). The cyclic voltammogram of the RRDE disk shows pronounced redox peaks in lithium hydroxide electrolytes with pH between 12 and 13.5, which we assign to bulk manganese redox based on XAS. The onset of the OER is pH-dependent on the scale of the reversible hydrogen electrode (RHE) with a Nernst slope of -40(4) mV/pH at -5 μA monitored at the RRDE ring. To connect this trend to catalyst changes, we develop a simple model for delithiation of LiMn2 O4 in LiOH electrolytes, which gives the same Nernst slope of delithiation as our experimental data, i. e., 116(25) mV/pH. From this data, we construct an ERHE -pH diagram that illustrates robustness of LiMn2 O4 against oxidation above pH 13.5 as also verified by XAS. We conclude that manganese oxidation is the origin of the increase of the OER overpotential at pH lower than 14 and also of the pH dependence on the RHE scale. Our work highlights that vulnerability to transition metal redox may lead to increased overpotentials, which is important for the design of stable electrocatalysts.
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  • Journal Article

    Correlations and forces in sheared fluids with or without quenching 

    Rohwer, Christian M.; Maciołek, Anna; Dietrich, S.; Krüger, Matthias
    New Journal of Physics 2019; 21(7): Art. 073029
    Spatial correlations play an important role in characterizing material properties related to non-local effects. Inter alia, they can give rise to fluctuation-induced forces. Equilibrium correlations in fluids provide an extensively studied paradigmatic case, in which their range is typically bounded by the correlation length. Out of equilibrium, conservation laws have been found to extend correlations beyond this length, leading, instead, to algebraic decays. In this context, here we present a systematic study of the correlations and forces in fluids driven out of equilibrium simultaneously by quenching and shearing, both for non-conserved as well as for conserved Langevin-type dynamics. Weidentify which aspects of the correlations are due to shear, due to quenching, and due to simultaneously applying both, and how these properties depend on the correlation length of the system and its compressibility. Both shearing and quenching lead to long-ranged correlations, which, however, differ in their nature as well as in their prefactors, and which are mixed up by applying both perturbations. These correlations are employed to compute non-equilibrium fluctuation-induced forces in the presence of shear, with or without quenching, thereby generalizing the framework set out by Dean and Gopinathan. These forces can be stronger or weaker compared to their counterparts in unsheared systems. In general, they do not point along the axis connecting the centers of the small inclusions considered to be embedded in the fluctuating medium. Since quenches or shearing appear to be realizable in a variety of systems with conserved particle number, including active matter, we expect these findings to be relevant for experimental investigations.
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  • Journal Article

    Radiative transfer distortions of Lyman α emitters: a new Fingers-of-God damping in the clustering in redshift space 

    Byrohl, Chris; Saito, Shun; Behrens, Christoph
    Monthly Notices of the Royal Astronomical Society 2019; 489(3) p.3472-3491
    Prior expectations of movement instructions can promote preliminary action planning and influence choices. We investigated how action priors affect action-goal encoding in premotor and parietal cortices and if they bias subsequent free choice. Monkeys planned reaches according to visual cues that indicated relative probabilities of two possible goals. On instructed trials, the reach goal was determined by a secondary cue respecting these probabilities. On rarely interspersed free-choice trials without instruction, both goals offered equal reward. Action priors induced graded free-choice biases and graded frontoparietal motor-goal activity, complementarily in two subclasses of neurons. Down-regulating neurons co-encoded both possible goals and decreased opposite-to-preferred responses with decreasing prior, possibly supporting a process of choice by elimination. Up-regulating neurons showed increased preferred-direction responses with increasing prior, likely supporting a process of computing net likelihood. Action-selection signals emerged earliest in down-regulating neurons of premotor cortex, arguing for an initiation of selection in the frontal lobe.
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  • Journal Article

    Estimating Lyapunov exponents in billiards 

    Datseris, George; Hupe, Lukas; Fleischmann, Ragnar
    Chaos: An Interdisciplinary Journal of Nonlinear Science 2019; 29(9): Art. 093115
    Dynamical billiards are paradigmatic examples of chaotic Hamiltonian dynamical systems with widespread applications in physics. We study how well their Lyapunov exponent, characterizing the chaotic dynamics, and its dependence on external parameters can be estimated from phase space volume arguments, with emphasis on billiards with mixed regular and chaotic phase spaces. We show that in the very diverse billiards considered here, the leading contribution to the Lyapunov exponent is inversely proportional to the chaotic phase space volume and subsequently discuss the generality of this relationship. We also extend the well established formalism by Dellago, Posch, and Hoover to calculate the Lyapunov exponents of billiards to include external magnetic fields and provide a software on its implementation.
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  • Journal Article

    Spontaneous termination of chaotic spiral wave dynamics in human cardiac ion channel models 

    Aron, Marcel; Herzog, Sebastian; Parlitz, Ulrich; Luther, Stefan; Lilienkamp, Thomas
    PLOS ONE 2019; 14(8): Art. e0221401
    Chaotic spiral or scroll wave dynamics can be found in diverse systems. In cardiac dynamics, spiral or scroll waves of electrical excitation determine the dynamics during life-threatening arrhythmias like ventricular fibrillation. In numerical studies it was found that chaotic episodes of spiral and scroll waves can be transient, thus they terminate spontaneously. We show in this study that this behavior can also be observed using models which describe the ion channel dynamics of human cardiomyocytes (Bueno-Orovio-Cherry-Fenton model and the Ten Tusscher-Noble-Noble-Panfilov model). For both models we find that the average lifetime of the chaotic transients grows exponentially with the system size. With this behavior, we classify the systems into the group of type-II supertransients. We observe a significant difference of the breakup behavior between the models, which results in a distinct dynamics during the final phase just before the termination. The observation of a (temporally) stable single-spiral state affects the prevailing description of the dynamics of type-II supertransients as being "quasi-stationary" and also the feasibility of predicting the spontaneous termination of the spiral wave dynamics. In the long term, the relation between the breakup behavior of spiral waves and properties of chaotic transients like predictability or average transient lifetime may contribute to an improved understanding and classification of cardiac arrhythmias.
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  • Journal Article

    Persistent accelerations disentangle Lagrangian turbulence 

    Bentkamp, Lukas; Lalescu, Cristian C.; Wilczek, Michael
    Nature Communications 2019; 10(1): Art. 3550
    Particles in turbulence frequently encounter extreme accelerations between extended periods of quiescence. The occurrence of extreme events is closely related to the intermittent spatial distribution of intense flow structures such as vorticity filaments. This mixed history of flow conditions leads to very complex particle statistics with a pronounced scale dependence, which presents one of the major challenges on the way to a non-equilibrium statistical mechanics of turbulence. Here, we introduce the notion of persistent Lagrangian acceleration, quantified by the squared particle acceleration coarse-grained over a viscous time scale. Conditioning Lagrangian particle data from simulations on this coarse-grained acceleration, we find remarkably simple, close-to-Gaussian statistics for a range of Reynolds numbers. This opens the possibility to decompose the complex particle statistics into much simpler sub-ensembles. Based on this observation, we develop a comprehensive theoretical framework for Lagrangian single-particle statistics that captures the acceleration, velocity increments as well as single-particle dispersion.
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  • Journal Article

    Bismuth Oxide Faceted Structures as a Photocatalyst Produced Using an Atmospheric Pressure Plasma Jet 

    Köhler, Robert; Siebert, Dominik; Kochanneck, Leif; Ohms, Gisela; Viöl, Wolfgang
    Catalysts 2019; 9(6): Art. 533
    The photocatalyst bismuth oxide, which is active under visual light, was deposited using an atmospheric pressure plasma jet (APPJ). Sixteen di erent samples were generated under di erent parameters of the APPJ to investigate their catalytic activity. The prepared samples were characterized using X-ray di raction (XRD), X-ray photoelectron spectroscopy (XPS), laser scanning microscopy (LSM), and UV–vis di use reflectance absorption spectroscopy. The measured data, such as average sample thickness, coverage ratio, phase fraction, chemical composition, band gap, and photocatalytic performance were used for comparing the samples. The XRD analysis showed that the deposition process produced a mixed phase of monocline Bi2O3 and tetragonal Bi2O2.33. Using the Rietveld refinement method, phase fractions could be determined and compared with the XPS data. The non-stoichiometric phases were influenced by the introduction of nitrogen to the surface as a result of the deposition process. The band gap calculated from the di use absorption spectroscopy shows that Bi2O2.33 with 2.78 eV had a higher band gap compared to the phases with a high proportion of Bi2O3 (2.64 eV). Furthermore, it was shown that the band gap was dependent on the thickness of the sample and oxygen vacancies or loss of oxygen in the surface. All coatings had degraded methyl orange (MO) under irradiation by xenon lamps.
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  • Journal Article

    Solar p-mode damping rates: Insight from a 3D hydrodynamical simulation 

    Belkacem, K.; Kupka, F.; Samadi, R.; Grimm-Strele, H.
    Astronomy & Astrophysics 2019; 625: Art. A20
    Space-borne missions such as CoRoT and Kepler have provided a rich harvest of high-quality photometric data for solar-like pulsators. It is now possible to measure damping rates for hundreds of main-sequence and thousands of red-giant stars with an unprecedented precision. However, among the seismic parameters, mode damping rates remain poorly understood and thus barely used for inferring the physical properties of stars. Previous approaches to model mode damping rates were based on mixing-length theory or a Reynoldsstress approach to model turbulent convection. While they can be used to grasp the main physics of the problem, such approaches are of little help to provide quantitative estimates as well as a definitive answer on the relative contribution of each physical mechanism. Indeed, due to the high complexity of the turbulent flow and its interplay with the oscillations, those theories rely on many free parameters which inhibits an in-depth understanding of the problem. Our aim is thus to assess the ability of 3D hydrodynamical simulations to infer the physical mechanisms responsible for damping of solar-like oscillations. To this end, a solar high-spatial resolution and long-duration hydrodynamical 3D simulation computed with the ANTARES code allows probing the coupling between turbulent convection and the normal modes of the simulated box. Indeed, normal modes of the simulation experience realistic driving and damping in the super-adiabatic layers of the simulation. Therefore, investigating the properties of the normal modes in the simulation provides a unique insight into the mode physics. We demonstrate that such an approach provides constraints on the solar damping rates and is able to disentangle the relative contribution related to the perturbation (by the oscillation) of the turbulent pressure, the gas pressure, the radiative flux, and the convective flux contributions. Finally, we conclude that using the normal modes of a 3D numerical simulation is possible and is potentially able to unveil the respective role of the di erent physical mechanisms responsible for mode damping provided the time-duration of the simulation is long enough.
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  • Journal Article

    Metal-induced energy transfer 

    Gregor, Ingo; Chizhik, Alexey; Karedla, Narain; Enderlein, Jörg
    Nanophotonics 2019; 8(10) p.1689-1699
    Since about a decade, metal-induced energy transfer (MIET) has become a tool to measure the distance of fluorophores to a metal-coated surface with nanometer accuracy. The energy transfer from a fluorescent molecule to surface plasmons within a metal film results in the acceleration of its radiative decay rate. This can be observed as a reduction of the molecule’s fluorescence lifetime which can be easily measured with standard microscopy equipment. The achievable distance resolution is in the nanometer range, over a total range of about 200 nm. The method is perfectly compatible with biological and even live cell samples. In this review, we will summarize the theoretical and technical details of the method and present the most important results that have been obtained using MIET. We will also show how the latest technical developments can contribute to improving MIET, and we sketch some interesting directions for its future applications in the life sciences.
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  • Journal Article

    Erratum to: Searching for flavored gauge bosons 

    Chun, Eung Jin; Das, Arindam; Kim, Jinsu; Kim, Jongkuk
    2019
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  • Journal Article

    Influence of particle size on the apparent electrocatalytic activity of LiMn2O4 for oxygen evolution 

    Baumung, Max; Schönewald, Florian; Erichsen, Torben; Volkert, Cynthia A.; Risch, Marcel
    Sustainable Energy & Fuels 2019; 3(9) p.2218-2226
    We investigate LiMn2O4 as a model catalyst for the oxygen evolution reaction (OER), because it shares the cubane structure with the active site of photosystem II. Specifically, we study the influence of different particle sizes of LiMn2O4 on the OER in a sodium hydroxide electrolyte. The product currents of manganese corrosion and oxygen evolution were obtained by rotating ring disk electrodes (RRDE). Physical characterization by various methods supports identical surface chemistry and microstructure of the pristine powders. We obtained similar oxygen current densities of 40(14) μA cmECSA−2 and 26(5) μA cmECSA−2 for micro- and nano-sized particles at 1.68 V vs. RHE. However, the total current densities differed drastically and while the micro-powder had a high disk current density of 205(2) μA cmECSA−2, its faradaic efficiency was only 25%. In contrast, the faradaic efficiency of the nanopowder was at least 75%. We hypothesize that a Mn redox process may occur in the bulk in parallel and possibly in combination with oxygen evolution on the surface based on the observed difference between the total and product current densities. Knowledge of the product currents is crucial for distinguishing the mechanisms of corrosion and catalysis and for designing better catalysts with high faradaic efficiency.
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  • Journal Article

    Envelope glycoprotein mobility on HIV-1 particles depends on the virus maturation state 

    Chojnacki, Jakub; Waithe, Dominic; Carravilla, Pablo; Huarte, Nerea; Galiani, Silvia; Enderlein, Jörg; Eggeling, Christian
    Nature Communications 2017; 8(1)
    Human immunodeficiency virus type 1 (HIV-1) assembles as immature particles, which require the proteolytic cleavage of structural polyprotein Gag and the clustering of envelope glycoprotein Env for infectivity. The details of mechanisms underlying Env clustering remain unknown. Here, we determine molecular dynamics of Env on the surface of individual HIV-1 particles using scanning fluorescence correlation spectroscopy on a super-resolution STED microscope. We find that Env undergoes a maturation-induced increase in mobility, highlighting diffusion as one cause for Env clustering. This mobility increase is dependent on Gag-interacting Env tail but not on changes in viral envelope lipid order. Diffusion of Env and other envelope incorporated proteins in mature HIV-1 is two orders of magnitude slower than in the plasma membrane, indicating that HIV-1 envelope is intrinsically a low mobility environment, mainly due to its general high lipid order. Our results provide insights into dynamic properties of proteins on the surface of individual virus particles.To become infectious, HIV-1 particles undergo a maturation process involving the clustering of envelope glycoprotein Env. Here, Chojnacki et al. employ super-resolution STED-FCS microscopy to study dynamics of Env molecules on HIV-1 particles and show that Env undergoes a maturation-induced increase in mobility.
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  • Journal Article

    Effect of Adhesion and Substrate Elasticity on Neutrophil Extracellular Trap Formation 

    Erpenbeck, Luise; Gruhn, Antonia Luise; Kudryasheva, Galina; Günay, Gökhan; Meyer, Daniel; Busse, Julia; Neubert, Elsa; Schön, Michael P.; Rehfeldt, Florian; Kruss, Sebastian
    Frontiers in Immunology 2019; 10: Art. 2320
    Neutrophils are the most abundant type of white blood cells. Upon stimulation, they are able to decondense and release their chromatin as neutrophil extracellular traps (NETs). This process (NETosis) is part of immune defense mechanisms but also plays an important role in many chronic and inflammatory diseases such as atherosclerosis, rheumatoid arthritis, diabetes, and cancer. For this reason,much effort has been invested into understanding biochemical signaling pathways in NETosis. However, the impact of the mechanical micro-environment and adhesion on NETosis is not well-understood. Here, we studied how adhesion and especially substrate elasticity affect NETosis. We employed polyacrylamide (PAA) gels with distinctly defined elasticities (Young’s modulus E) within the physiologically relevant range from 1 to 128 kPa and coated the gels with integrin ligands (collagen I, fibrinogen). Neutrophils were cultured on these substrates and stimulated with potent inducers of NETosis: phorbol 12-myristate 13-acetate (PMA) and lipopolysaccharide (LPS). Interestingly, PMA-induced NETosis was neither affected by substrate elasticity nor by different integrin ligands. In contrast, for LPS stimulation, NETosis rates increased with increasing substrate elasticity (E > 20 kPa). LPS-induced NETosis increased with increasing cell contact area, while PMA-induced NETosis did not require adhesion at all. Furthermore, inhibition of phosphatidylinositide 3 kinase (PI3K), which is involved in adhesion signaling, completely abolished LPS-induced NETosis but only slightly decreased PMA-induced NETosis. In summary, we show that LPS-induced NETosis depends on adhesion and substrate elasticity while PMA-induced NETosis is completely independent of adhesion.
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  • Journal Article

    Lateral Subunit Coupling Determines Intermediate Filament Mechanics 

    Lorenz, Charlotta; Forsting, Johanna; Schepers, Anna V.; Kraxner, Julia; Bauch, Susanne; Witt, Hannes; Klumpp, Stefan; Köster, Sarah
    Physical Review Letters
    The cytoskeleton is a composite network of three types of protein filaments, among which in-termediate filaments (IFs) are the most extensible ones. Two very important IFs are keratin and vimentin, which have similar molecular architectures, but different mechanical behaviors. Here we compare the mechanical response of single keratin and vimentin filaments using optical tweezers. We show that the mechanics of vimentin strongly depends on the ionic strength of the buffer and that its force-strain curve suggests a high degree of cooperativity between subunits. Indeed, a computational model indicates that in contrast to keratin, vimentin is characterized by strong lateral subunit coupling of its charged monomers during unfolding of α-helices. We conclude that cells can tune their mechanics by differential use of keratin versus vimentin.
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  • Journal Article

    A study of the radiation tolerance of poly-crystalline and single-crystalline CVD diamond to 800 MeV and 24 GeV protons 

    Bäni, L.; Alexopoulos, A.; Artuso, M.; Bachmair, F.; Bartosik, M.; Beck, H.; Bellini, V.; Belyaev, V.; Bentele, B.; Bes, A.; et al.
    Brom, J.-M.Bruzzi, M.Chiodini, G.Chren, D.Cindro, V.Claus, G.Collot, J.Cumalat, J.Dabrowski, A.D’Alessandro, R.Dauvergne, D.de Boer, W.Dick, S.Dorfer, C.Dünser, M.Eremin, V.Forcolin, G.Forneris, J.Gallin-Martel, L.Gallin-Martel, M.-L.Gan, K. K.Gastal, M.Giroletti, C.Goffe, M.Goldstein, J.Golubev, A.Gorišek, A.Grigoriev, E.Grosse-Knetter, J.Grummer, A.Gui, B.Guthoff, M.Hiti, B.Hits, D.Hoeferkamp, M.Hofmann, T.Hosselet, J.Hostachy, J.-Y.Hügging, F.Hutton, C.Janssen, J.Kagan, H.Kanxheri, K.Kasieczka, G.Kass, R.Kis, M.Kramberger, G.Kuleshov, S.Lacoste, A.Lagomarsino, S.Lo Giudice, A.Paz, I. LopezLukosi, E.Maazouzi, C.Mandic, I.Mathieu, C.Menichelli, M.Mikuž, M.Morozzi, A.Moss, J.Mountain, R.Oh, A.Olivero, P.Passeri, D.Pernegger, H.Perrino, R.Piccini, M.Picollo, F.Pomorski, M.Potenza, R.Quadt, A.Rarbi, F.Re, A.Reichmann, M.Roe, S.Becerra, D. A .SanzScaringella, M.Schaffner, D.Schmidt, C. J.Schnetzer, S.Schioppa, E.Sciortino, S.Scorzoni, A.Seidel, S.Servoli, L.Smith, D. S.Sopko, B.Sopko, V.Spagnolo, S.Spanier, S.Stenson, K.Stone, R.Sutera, C.Traeger, M.Trischuk, W.Truccato, M.Tuve, C.Velthuis, J.Venturi, N.Wagner, S.Wallny, R.Wang, J. C.Weingarten, J.Weiss, C.Wengler, T.Wermes, N.Yamouni, M.Zavrtanik, M.
    Journal of Physics D: Applied Physics 2019; 52(46): Art. 465103
    We have measured the radiation tolerance of poly-crystalline and single-crystalline diamonds grown by the chemical vapor deposition (CVD) process by measuring the charge collected before and after irradiation in a 50 m pitch strip detector fabricated on each diamond sample. We irradiated one group of sensors with 800 MeV protons, and a second group of sensors with 24 GeV protons, in steps, to protons cm−2 and protons cm−2 respectively. We observe the sum of mean drift paths for electrons and holes for both poly-crystalline CVD diamond and single-crystalline CVD diamond decreases with irradiation fluence from its initial value according to a simple damage curve characterized by a damage constant for each irradiation energy and the irradiation fluence. We find for each irradiation energy the damage constant, for poly-crystalline CVD diamond to be the same within statistical errors as the damage constant for single-crystalline CVD diamond. We find the damage constant for diamond irradiated with 24 GeV protons to be and the damage constant for diamond irradiated with 800 MeV protons to be . Moreover, we observe the pulse height decreases with fluence for poly-crystalline CVD material and within statistical errors does not change with fluence for single-crystalline CVD material for both 24 GeV proton irradiation and 800 MeV proton irradiation. Finally, we have measured the uniformity of each sample as a function of fluence and observed that for poly-crystalline CVD diamond the samples become more uniform with fluence while for single-crystalline CVD diamond the uniformity does not change with fluence.
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