TY - JOUR A1 - Lewandowsky, Stephan A1 - Cowtan, Kevin A1 - Risbey, James S. A1 - Mann, Michael E. A1 - Steinman, Byron A. A1 - Oreskes, Naomi A1 - Rahmstorf, Stefan T1 - The 'pause' in global warming in historical context BT - (II). comparing models to observations JF - Environmental research letters N2 - We review the evidence for a putative early 21st-century divergence between global mean surface temperature (GMST) and Coupled Model Intercomparison Project Phase 5 (CMIP5) projections. We provide a systematic comparison between temperatures and projections using historical versions of GMST products and historical versions of model projections that existed at the times when claims about a divergence were made. The comparisons are conducted with a variety of statistical techniques that correct for problems in previous work, including using continuous trends and a Monte Carlo approach to simulate internal variability. The results show that there is no robust statistical evidence for a divergence between models and observations. The impression of a divergence early in the 21st century was caused by various biases in model interpretation and in the observations, and was unsupported by robust statistics. Y1 - 2018 U6 - https://doi.org/10.1088/1748-9326/aaf372 SN - 1748-9326 VL - 13 IS - 12 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Metzler, Ralf T1 - Superstatistics and non-Gaussian diffusion JF - The European physical journal special topics N2 - Brownian motion and viscoelastic anomalous diffusion in homogeneous environments are intrinsically Gaussian processes. In a growing number of systems, however, non-Gaussian displacement distributions of these processes are being reported. The physical cause of the non-Gaussianity is typically seen in different forms of disorder. These include, for instance, imperfect "ensembles" of tracer particles, the presence of local variations of the tracer mobility in heteroegenous environments, or cases in which the speed or persistence of moving nematodes or cells are distributed. From a theoretical point of view stochastic descriptions based on distributed ("superstatistical") transport coefficients as well as time-dependent generalisations based on stochastic transport parameters with built-in finite correlation time are invoked. After a brief review of the history of Brownian motion and the famed Gaussian displacement distribution, we here provide a brief introduction to the phenomenon of non-Gaussianity and the stochastic modelling in terms of superstatistical and diffusing-diffusivity approaches. KW - Brownian diffusion KW - anomalous diffusion KW - dynamics KW - kinetic-theory KW - models KW - motion KW - nanoparticles KW - nonergodicity KW - statistics KW - subdiffusion Y1 - 2020 U6 - https://doi.org/10.1140/epjst/e2020-900210-x SN - 1951-6355 SN - 1951-6401 VL - 229 IS - 5 SP - 711 EP - 728 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Norregaard, Kamilla A1 - Metzler, Ralf A1 - Ritter, Christine M. A1 - Berg-Sorensen, Kirstine A1 - Oddershede, Lene Broeng T1 - Manipulation and Motion of Organelles and Single Molecules in Living Cells JF - Chemical reviews N2 - The biomolecule is among the most important building blocks of biological systems, and a full understanding of its function forms the scaffold for describing the mechanisms of higher order structures as organelles and cells. Force is a fundamental regulatory mechanism of biomolecular interactions driving many cellular processes. The forces on a molecular scale are exactly in the range that can be manipulated and probed with single molecule force spectroscopy. The natural environment of a biomolecule is inside a living cell, hence, this is the most relevant environment for probing their function. In vivo studies are, however, challenged by the complexity of the cell. In this review, we start with presenting relevant theoretical tools for analyzing single molecule data obtained in intracellular environments followed by a description of state-of-the art visualization techniques. The most commonly used force spectroscopy techniques, namely optical tweezers, magnetic tweezers, and atomic force microscopy, are described in detail, and their strength and limitations related to in vivo experiments are discussed. Finally, recent exciting discoveries within the field of in vivo manipulation and dynamics of single molecule and organelles are reviewed. Y1 - 2017 U6 - https://doi.org/10.1021/acs.chemrev.6b00638 SN - 0009-2665 SN - 1520-6890 VL - 117 IS - 5 SP - 4342 EP - 4375 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Szalay, J. R. A1 - Poppe, A. R. A1 - Agarwal, J. A1 - Britt, D. A1 - Belskaya, I. A1 - Horanyi, M. A1 - Nakamura, T. A1 - Sachse, M. A1 - Spahn, Frank T1 - Dust Phenomena Relating to Airless Bodies JF - Space science reviews N2 - Airless bodies are directly exposed to ambient plasma and meteoroid fluxes, making them characteristically different from bodies whose dense atmospheres protect their surfaces from such fluxes. Direct exposure to plasma and meteoroids has important consequences for the formation and evolution of planetary surfaces, including altering chemical makeup and optical properties, generating neutral gas and/or dust exospheres, and leading to the generation of circumplanetary and interplanetary dust grain populations. In the past two decades, there have been many advancements in our understanding of airless bodies and their interaction with various dust populations. In this paper, we describe relevant dust phenomena on the surface and in the vicinity of airless bodies over a broad range of scale sizes from to , with a focus on recent developments in this field. KW - Dust KW - Airless bodies KW - Interplanetary dust Y1 - 2018 U6 - https://doi.org/10.1007/s11214-018-0527-0 SN - 0038-6308 SN - 1572-9672 VL - 214 IS - 5 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Spahn, Frank A1 - Sachse, Manuel A1 - Seiss, Martin A1 - Hsu, Hsiang-Wen A1 - Kempf, Sascha A1 - Horanyi, Mihaly T1 - Circumplanetary Dust Populations JF - Space science reviews N2 - We summarize the current state of observations of circumplanetary dust populations, including both dilute and dense rings and tori around the giant planets, ejecta clouds engulfing airless moons, and rings around smaller planetary bodies throughout the Solar System. We also discuss the theoretical models that enable these observations to be understood in terms of the sources, sinks and transport of various dust populations. The dynamics and resulting transport of the particles can be quite complex, due to the fact that their motion is influenced by neutral and plasma drag, radiation pressure, and electromagnetic forcesall in addition to gravity. The relative importance of these forces depends on the environment, as well as the makeup and size of the particles. Possible dust sources include the generation of ejecta particles by impacts, active volcanoes and geysers, and the capture of exogenous particles. Possible dust sinks include collisions with moons, rings, or the central planet, erosion due to sublimation and sputtering, even ejection and escape from the circumplanetary environment. KW - Circumplanetary dust KW - Planetary rings and tori KW - Dust sources and sinks KW - Dust dynamics Y1 - 2019 U6 - https://doi.org/10.1007/s11214-018-0577-3 SN - 0038-6308 SN - 1572-9672 VL - 215 IS - 1 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Dai, Xiaolin A1 - Böker, Alexander A1 - Glebe, Ulrich T1 - Broadening the scope of sortagging JF - RSC Advances N2 - Sortases are enzymes occurring in the cell wall of Gram-positive bacteria. Sortase A (SrtA), the best studied sortase class, plays a key role in anchoring surface proteins with the recognition sequence LPXTG covalently to oligoglycine units of the bacterial cell wall. This unique transpeptidase activity renders SrtA attractive for various purposes and motivated researchers to study multiple in vivo and in vitro ligations in the last decades. This ligation technique is known as sortase-mediated ligation (SML) or sortagging and developed to a frequently used method in basic research. The advantages are manifold: extremely high substrate specificity, simple access to substrates and enzyme, robust nature and easy handling of sortase A. In addition to the ligation of two proteins or peptides, early studies already included at least one artificial (peptide equipped) substrate into sortagging reactions - which demonstrates the versatility and broad applicability of SML. Thus, SML is not only a biology-related technique, but has found prominence as a major interdisciplinary research tool. In this review, we provide an overview about the use of sortase A in interdisciplinary research, mainly for protein modification, synthesis of protein-polymer conjugates and immobilization of proteins on surfaces. Y1 - 2019 U6 - https://doi.org/10.1039/c8ra06705h SN - 2046-2069 VL - 9 IS - 9 SP - 4700 EP - 4721 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Santer, Svetlana T1 - Remote control of soft nano-objects by light using azobenzene containing surfactants JF - Journal of physics ; D, Applied physics N2 - We review recent progress in the field of light responsive soft nano-objects. These are systems the shape, size, surface area and surface energy of which can be easily changed by low-intensity external irradiation. Here we shall specifically focus on microgels, DNA molecules, polymer brushes and colloidal particles. One convenient way to render these objects photosensitive is to couple them via ionic and/or hydrophobic interactions with azobenzene containing surfactants in a non-covalent way. The advantage of this strategy is that these surfactants can make any type of charged object light responsive without the need for possibly complicated (and irreversible) chemical conjugation. In the following, we will exclusively discuss only photosensitive surfactant systems. These contain a charged head and a hydrophobic tail into which an azobenzene group is incorporated, which can undergo reversible photo-isomerization from a trans-to a cis-configuration under UV illumination. These kinds of photo-isomerizations occur on a picosecond timescale and are fully reversible. The two isomers in general possess different polarity, i.e. the trans-state is less polar with a dipole moment of usually close to 0 Debye, while the cis-isomer has a dipole moment up to 3 Debye or more, depending on additional phenyl ring substituents. As part of the hydrophobic tail of a surfactant molecule, the photo-isomerization also changes the hydrophobicity of the molecule as a whole and hence its solubility, surface energy, and strength of interaction with other substances. Being a molecular actuator, which converts optical energy in to mechanical work, the azobenzene group in the shape of surfactant molecule can be utilized in order to actuate matter on larger time and length scale. In this paper we show several interesting examples, where azobenzene containing surfactants play the role of a transducer mediating between different states of size, shape, surface energy and spatial arrangement of various nanoscale soft-material systems. KW - photosensitive surfactants KW - azobenzene KW - photosensitive soft objects KW - light responsive microgels KW - light responsive polymer brushes KW - light responsive DNA Y1 - 2017 U6 - https://doi.org/10.1088/1361-6463/aa95ca SN - 0022-3727 SN - 1361-6463 VL - 51 IS - 1 PB - IOP Publ. CY - Bristol ER - TY - JOUR A1 - Bulla, Mattia A1 - Coughlin, Michael W. A1 - Dhawan, Suhail A1 - Dietrich, Tim T1 - Multi-messenger constraints on the Hubble constant through combination of gravitational waves, gamma-ray bursts and kilonovae from neutron star mergers JF - Universe : open access journal N2 - The simultaneous detection of gravitational waves and light from the binary neutron star merger GW170817 led to independent measurements of distance and redshift, providing a direct estimate of the Hubble constant H-0 that does not rely on a cosmic distance ladder, nor assumes a specific cosmological model. By using gravitational waves as "standard sirens", this approach holds promise to arbitrate the existing tension between the H-0 value inferred from the cosmic microwave background and those obtained from local measurements. However, the known degeneracy in the gravitational-wave analysis between distance and inclination of the source led to a H-0 value from GW170817 that was not precise enough to resolve the existing tension. In this review, we summarize recent works exploiting the viewing-angle dependence of the electromagnetic signal, namely the associated short gamma-ray burst and kilonova, to constrain the system inclination and improve on H-0. We outline the key ingredients of the different methods, summarize the results obtained in the aftermath of GW170817 and discuss the possible systematics introduced by each of these methods. KW - gravitational waves KW - stars: neutron KW - stars: binaries KW - cosmology: cosmological parameters KW - cosmology: distance scale KW - cosmology: cosmic background radiation Y1 - 2022 U6 - https://doi.org/10.3390/universe8050289 SN - 2218-1997 VL - 8 IS - 5 PB - MDPI CY - Basel ER - TY - JOUR A1 - Laquai, Frederic A1 - Andrienko, Denis A1 - Deibel, Carsten A1 - Neher, Dieter T1 - Charge carrier generation, recombination, and extraction in polymer-fullerene bulk heterojunction organic solar cells JF - Elementary processes in organic photovoltaics N2 - In this chapter we review the basic principles of photocurrent generation in bulk heterojunction organic solar cells, discuss the loss channels limiting their efficiency, and present case studies of several polymer-fullerene blends. Using steady-state and transient, optical, and electrooptical techniques, we create a precise picture of the fundamental processes that ultimately govern solar cell efficiency. KW - Charge extraction KW - Charge generation KW - Charge recombination KW - Organic solar cells KW - PBT7 KW - PBTTT KW - PCPDTBT Y1 - 2026 SN - 978-3-319-28338-8 SN - 978-3-319-28336-4 U6 - https://doi.org/10.1007/978-3-319-28338-8_11 SN - 0065-3195 VL - 272 SP - 267 EP - 291 PB - Springer CY - Berlin ER - TY - JOUR A1 - Shprits, Yuri Y. A1 - Angelopoulos, V. A1 - Russell, C. T. A1 - Strangeway, R. J. A1 - Runov, A. A1 - Turner, D. A1 - Caron, R. A1 - Cruce, P. A1 - Leneman, D. A1 - Michaelis, I. A1 - Petrov, V. A1 - Panasyuk, M. A1 - Yashin, I. A1 - Drozdov, Alexander A1 - Russell, C. L. A1 - Kalegaev, V. A1 - Nazarkov, I. A1 - Clemmons, J. H. T1 - Scientific Objectives of Electron Losses and Fields INvestigation Onboard Lomonosov Satellite JF - Space science reviews N2 - The objective of the Electron Losses and Fields INvestigation on board the Lomonosov satellite ( ELFIN-L) project is to determine the energy spectrum of precipitating energetic electrons and ions and, together with other polar-orbiting and equatorial missions, to better understand the mechanisms responsible for scattering these particles into the atmosphere. This mission will provide detailed measurements of the radiation environment at low altitudes. The 400-500 km sun-synchronous orbit of Lomonosov is ideal for observing electrons and ions precipitating into the atmosphere. This mission provides a unique opportunity to test the instruments. Similar suite of instruments will be flown in the future NSF-and NASA-supported spinning CubeSat ELFIN satellites which will augment current measurements by providing detailed information on pitch-angle distributions of precipitating and trapped particles. KW - Magnetospheric physics KW - Observations KW - Particles precipitating KW - Particles trapped KW - Radiation belts Y1 - 2017 U6 - https://doi.org/10.1007/s11214-017-0455-4 SN - 0038-6308 SN - 1572-9672 VL - 214 IS - 1 PB - Springer CY - Dordrecht ER -