@misc{deVeraAlawiBackhausetal.2019, author = {de Vera, Jean-Pierre Paul and Alawi, Mashal and Backhaus, Theresa and Baque, Mickael and Billi, Daniela and Boettger, Ute and Berger, Thomas and Bohmeier, Maria and Cockell, Charles and Demets, Rene and de la Torre Noetzel, Rosa and Edwards, Howell and Elsaesser, Andreas and Fagliarone, Claudia and Fiedler, Annelie and Foing, Bernard and Foucher, Frederic and Fritz, J{\"o}rg and Hanke, Franziska and Herzog, Thomas and Horneck, Gerda and H{\"u}bers, Heinz-Wilhelm and Huwe, Bj{\"o}rn and Joshi, Jasmin Radha and Kozyrovska, Natalia and Kruchten, Martha and Lasch, Peter and Lee, Natuschka and Leuko, Stefan and Leya, Thomas and Lorek, Andreas and Martinez-Frias, Jesus and Meessen, Joachim and Moritz, Sophie and Moeller, Ralf and Olsson-Francis, Karen and Onofri, Silvano and Ott, Sieglinde and Pacelli, Claudia and Podolich, Olga and Rabbow, Elke and Reitz, G{\"u}nther and Rettberg, Petra and Reva, Oleg and Rothschild, Lynn and Garcia Sancho, Leo and Schulze-Makuch, Dirk and Selbmann, Laura and Serrano, Paloma and Szewzyk, Ulrich and Verseux, Cyprien and Wadsworth, Jennifer and Wagner, Dirk and Westall, Frances and Wolter, David and Zucconi, Laura}, title = {Limits of life and the habitability of Mars}, series = {Astrobiology}, volume = {19}, journal = {Astrobiology}, number = {2}, publisher = {Liebert}, address = {New Rochelle}, issn = {1531-1074}, doi = {10.1089/ast.2018.1897}, pages = {145 -- 157}, year = {2019}, abstract = {BIOMEX (BIOlogy and Mars EXperiment) is an ESA/Roscosmos space exposure experiment housed within the exposure facility EXPOSE-R2 outside the Zvezda module on the International Space Station (ISS). The design of the multiuser facility supports-among others-the BIOMEX investigations into the stability and level of degradation of space-exposed biosignatures such as pigments, secondary metabolites, and cell surfaces in contact with a terrestrial and Mars analog mineral environment. In parallel, analysis on the viability of the investigated organisms has provided relevant data for evaluation of the habitability of Mars, for the limits of life, and for the likelihood of an interplanetary transfer of life (theory of lithopanspermia). In this project, lichens, archaea, bacteria, cyanobacteria, snow/permafrost algae, meristematic black fungi, and bryophytes from alpine and polar habitats were embedded, grown, and cultured on a mixture of martian and lunar regolith analogs or other terrestrial minerals. The organisms and regolith analogs and terrestrial mineral mixtures were then exposed to space and to simulated Mars-like conditions by way of the EXPOSE-R2 facility. In this special issue, we present the first set of data obtained in reference to our investigation into the habitability of Mars and limits of life. This project was initiated and implemented by the BIOMEX group, an international and interdisciplinary consortium of 30 institutes in 12 countries on 3 continents. Preflight tests for sample selection, results from ground-based simulation experiments, and the space experiments themselves are presented and include a complete overview of the scientific processes required for this space experiment and postflight analysis. The presented BIOMEX concept could be scaled up to future exposure experiments on the Moon and will serve as a pretest in low Earth orbit.}, language = {en} } @article{deVeraBoettgerdelaTorreNoetzeletal.2012, author = {de Vera, Jean-Pierre Paul and B{\"o}ttger, Ute and de la Torre N{\"o}tzel, Rosa and Sanchez, Francisco J. and Grunow, Dana and Schmitz, Nicole and Lange, Caroline and H{\"u}bers, Heinz-Wilhelm and Billi, Daniela and Baque, Mickael and Rettberg, Petra and Rabbow, Elke and Reitz, G{\"u}nther and Berger, Thomas and M{\"o}ller, Ralf and Bohmeier, Maria and Horneck, Gerda and Westall, Frances and J{\"a}nchen, Jochen and Fritz, J{\"o}rg and Meyer, Cornelia and Onofri, Silvano and Selbmann, Laura and Zucconi, Laura and Kozyrovska, Natalia and Leya, Thomas and Foing, Bernard and Demets, Rene and Cockell, Charles S. and Bryce, Casey and Wagner, Dirk and Serrano, Paloma and Edwards, Howell G. M. and Joshi, Jasmin Radha and Huwe, Bj{\"o}rn and Ehrenfreund, Pascale and Elsaesser, Andreas and Ott, Sieglinde and Meessen, Joachim and Feyh, Nina and Szewzyk, Ulrich and Jaumann, Ralf and Spohn, Tilman}, title = {Supporting Mars exploration BIOMEX in Low Earth Orbit and further astrobiological studies on the Moon using Raman and PanCam technology}, series = {Planetary and space science}, volume = {74}, journal = {Planetary and space science}, number = {1}, publisher = {Elsevier}, address = {Oxford}, issn = {0032-0633}, doi = {10.1016/j.pss.2012.06.010}, pages = {103 -- 110}, year = {2012}, abstract = {The Low Earth Orbit (LEO) experiment Biology and Mars Experiment (BIOMEX) is an interdisciplinary and international space research project selected by ESA. The experiment will be accommodated on the space exposure facility EXPOSE-R2 on the International Space Station (ISS) and is foreseen to be launched in 2013. The prime objective of BIOMEX is to measure to what extent biomolecules, such as pigments and cellular components, are resistant to and able to maintain their stability under space and Mars-like conditions. The results of BIOMEX will be relevant for space proven biosignature definition and for building a biosignature data base (e.g. the proposed creation of an international Raman library). The library will be highly relevant for future space missions such as the search for life on Mars. The secondary scientific objective is to analyze to what extent terrestrial extremophiles are able to survive in space and to determine which interactions between biological samples and selected minerals (including terrestrial, Moon- and Mars analogs) can be observed under space and Mars-like conditions. In this context, the Moon will be an additional platform for performing similar experiments with negligible magnetic shielding and higher solar and galactic irradiation compared to LEO. Using the Moon as an additional astrobiological exposure platform to complement ongoing astrobiological LEO investigations could thus enhance the chances of detecting organic traces of life on Mars. We present a lunar lander mission with two related objectives: a lunar lander equipped with Raman and PanCam instruments which can analyze the lunar surface and survey an astrobiological exposure platform. This dual use of testing mission technology together with geo- and astrobiological analyses will significantly increase the science return, and support the human preparation objectives. It will provide knowledge about the Moon's surface itself and, in addition, monitor the stability of life-markers, such as cells, cell components and pigments, in an extraterrestrial environment with much closer radiation properties to the surface of Mars. The combination of a Raman data base of these data together with data from LEO and space simulation experiments, will lead to further progress on the analysis and interpretation of data that we will obtain from future Moon and Mars exploration missions.}, language = {en} } @article{KuehnPingelBreusingetal.2011, author = {Kuehn, Sergei and Pingel, Patrick and Breusing, Markus and Fischer, Thomas and Stumpe, Joachim and Neher, Dieter and Elsaesser, Thomas}, title = {High-Resolution Near-Field Optical Investigation of Crystalline Domains in Oligomeric PQT-12 Thin Films}, series = {Advanced functional materials}, volume = {21}, journal = {Advanced functional materials}, number = {5}, publisher = {Wiley-Blackwell}, address = {Malden}, issn = {1616-301X}, doi = {10.1002/adfm.201001978}, pages = {860 -- 868}, year = {2011}, abstract = {The structure and morphology on different length scales dictate both the electrical and optical properties of organic semiconductor thin films. Using a combination of spectroscopic methods, including scanning near-field optical microscopy, we study the domain structure and packing quality of highly crystalline thin films of oligomeric PQT-12 with 100 nanometer spatial resolution. The pronounced optical anisotropy of these layers measured by polarized light microscopy facilitates the identification of regions with uniform molecular orientation. We find that a hierarchical order on three different length scales exists in these layers, made up of distinct well-ordered dichroic areas at the ten-micrometer-scale, which are sub-divided into domains with different molecular in-plane orientation. These serve as a template for the formation of smaller needle-like crystallites at the layer surface. A high degree of crystalline order is believed to be the cause of the rather high field-effect mobility of these layers of 10(-3) cm 2 V(-1) s(-1), whereas it is limited by the presence of domain boundaries at macroscopic distances.}, language = {en} } @article{WoernervonKorffSchmisingBargheeretal.2009, author = {Woerner, Michael and von Korff Schmising, Clemens and Bargheer, Matias and Zhavoronkov, Nickolai and Vrejoiu, Ionela and Hesse, Dietrich and Alexe, Marin and Elsaesser, Thomas}, title = {Ultrafast structural dynamics of perovskite superlattices}, issn = {0947-8396}, doi = {10.1007/s00339-009-5174-6}, year = {2009}, abstract = {Femtosecond x-ray diffraction provides direct insight into the ultrafast reversible lattice dynamics of materials with a perovskite structure. Superlattice (SL) structures consisting of a sequence of nanometer-thick layer pairs allow for optically inducing a tailored stress profile that drives the lattice motions and for limiting the influence of strain propagation on the observed dynamics. We demonstrate this concept in a series of diffraction experiments with femtosecond time resolution, giving detailed information on the ultrafast lattice dynamics of ferroelectric and ferromagnetic superlattices. Anharmonically coupled lattice motions in a SrRuO3/PbZr0.2Ti0.8O3 (SRO/ PZT) SL lead to a switch-off of the electric polarizations on a time scale of the order of 1 ps. Ultrafast magnetostriction of photoexcited SRO layers is demonstrated in a SRO/SrTiO3 (STO) SL.}, language = {en} } @article{ZamponiAnsarivonKorffSchmisingetal.2009, author = {Zamponi, Flavio and Ansari, Zunaira and von Korff Schmising, Clemens and Rothhardt, Philip and Zhavoronkov, Nickolai and Woerner, Michael and Elsaesser, Thomas and Bargheer, Matias and Trobitzsch-Ryll, Timo and Haschke, Michael}, title = {Femtosecond hard X-ray plasma sources with a kilohertz repetition rate}, issn = {0947-8396}, doi = {10.1007/s00339-009-5171-9}, year = {2009}, abstract = {Laser-driven plasma sources of femtosecond hard X-ray pulses have found widespread application in ultrafast X- ray diffraction. The recent development of plasma sources working at kilohertz repetition rates has allowed for diffraction experiments with strongly improved sensitivity, now revealing subtle fully reversible changes of the geometry of crystal lattices. We provide a brief review of this development and present a novel plasma source with an optimized mechanical and optical design, providing a high flux of several 10(10) photons/s at the Cu-K alpha energy of 8.04 keV and a pulse duration of a parts per thousand currency sign300 fs. First experiments, including the generation of Debye-Scherrer diffraction patterns from Si powder, demonstrate the high performance of this source.}, language = {en} } @article{FujikuraElsaesserBreuningeretal.2014, author = {Fujikura, Ushio and Elsaesser, Lore and Breuninger, Holger and Sanchez-Rodriguez, Clara and Ivakov, Alexander and Laux, Thomas and Findlay, Kim and Persson, Staffan and Lenhard, Michael}, title = {Atkinesin-13A modulates cell-wall synthesis and cell expansion in arabidopsis thaliana via the THESEUS1 pathway}, series = {PLoS Genetics : a peer-reviewed, open-access journal}, volume = {10}, journal = {PLoS Genetics : a peer-reviewed, open-access journal}, number = {9}, publisher = {PLoS}, address = {San Fransisco}, issn = {1553-7390}, doi = {10.1371/journal.pgen.1004627}, pages = {15}, year = {2014}, abstract = {Growth of plant organs relies on cell proliferation and expansion. While an increasingly detailed picture about the control of cell proliferation is emerging, our knowledge about the control of cell expansion remains more limited. We demonstrate the internal-motor kinesin AtKINESIN-13A (AtKIN13A) limits cell expansion and cell size in Arabidopsis thaliana, ion atkinl3a mutants forming larger petals with larger cells. The homolog, AtKINESIN-13B, also affects cell expansion and double mutants display growth, gametophytic and early embryonic defects, indicating a redundant role of he two genes. AtKIN13A is known to depolymerize microtubules and influence Golgi motility and distribution. Consistent his function, AtKIN13A interacts genetically with ANGUSTIFOLIA, encoding a regulator of Golgi dynamics. Reduced AtIGN13A activity alters cell wall structure as assessed by Fourier-transformed infrared-spectroscopy and triggers signalling he THESEUS1-dependent cell-wall integrity pathway, which in turn promotes the excess cell expansion in the atkinl3a mutant. Thus, our results indicate that the intracellular activity of AtKIN13A regulates cell expansion and wall architecture via THESEUS1, providing a compelling case of interplay between cell wall integrity sensing and expansion.}, language = {en} }