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We propose a fibre-based approach for generation of optical frequency combs (OFCs) with the aim of calibration of astronomical spectrographs in the low and medium-resolution range. This approach includes two steps: in the first step, an appropriate state of optical pulses is generated and subsequently moulded in the second step delivering the desired OFC. More precisely, the first step is realised by injection of two continuous-wave (CW) lasers into a conventional single-mode fibre, whereas the second step generates a broad OFC by using the optical solitons generated in step one as initial condition. We investigate the conversion of a bichromatic input wave produced by two initial CW lasers into a train of optical solitons, which happens in the fibre used as step one. Especially, we are interested in the soliton content of the pulses created in this fibre. For that, we study different initial conditions (a single cosine-hump, an Akhmediev breather, and a deeply modulated bichromatic wave) by means of soliton radiation beat analysis and compare the results to draw conclusion about the soliton content of the state generated in the first step. In case of a deeply modulated bichromatic wave, we observed the formation of a collective soliton crystal for low input powers and the appearance of separated solitons for high input powers. An intermediate state showing the features of both, the soliton crystal and the separated solitons, turned out to be most suitable for the generation of OFC for the purpose of calibration of astronomical spectrographs.
KEYCIT 2014
(2015)
In our rapidly changing world it is increasingly important not only to be an expert in a chosen field of study but also to be able to respond to developments, master new approaches to solving problems, and fulfil changing requirements in the modern world and in the job market. In response to these needs key competencies in understanding, developing and using new digital technologies are being brought into focus in school and university programmes. The IFIP TC3 conference "KEYCIT – Key Competences in Informatics and ICT (KEYCIT 2014)" was held at the University of Potsdam in Germany from July 1st to 4th, 2014 and addressed the combination of key competencies, Informatics and ICT in detail. The conference was organized into strands focusing on secondary education, university education and teacher education (organized by IFIP WGs 3.1 and 3.3) and provided a forum to present and to discuss research, case studies, positions, and national perspectives in this field.
Seit 1990 ist die vereinte, wieder souveräne Bundesrepublik Deutschland auf der Suche nach ihrer Rolle in der Welt. Auch die akademische Debatte um die Orientierung deutscher Außenpolitik und die ihr zugrundeliegenden Interessen hält seitdem an. In welchem Verhältnis stehen Normen und Werte einerseits und pragmatische, meist wirtschaftliche Interessen andererseits zueinander? Wie verhält sich die deutsche Außenpolitik zur europäischen? Beeinflusst oder dominiert die deutsche Position gar die europäische? Am Beispiel der deutschen Außenpolitik gegenüber den zentralasiatischen Staaten Kasachstan, Kirgisistan, Tadschikistan, Turkmenistan und Usbekistan werden diese Fragen diskutiert.
Spatio-temporal control of cellular uptake achieved by photoswitchable cell-penetrating peptides
(2015)
The selective uptake of compounds into specific cells of interest is a major objective in cell biology and drug delivery. By incorporation of a novel, thermostable azobenzene moiety we generated peptides that can be switched optically between an inactive state and an active, cell-penetrating state with excellent spatio-temporal control.
The genetic integrity of each organism depends on the faithful segregation of its genome during mitosis. To meet this challenge, a cellular surveillance mechanism, termed the spindle assembly checkpoint (SAC), evolved that monitors the correct attachment of chromosomes and blocks progression through mitosis if corrections are needed. While the central role of the SAC for genome integrity is well established, its functional dissection has been hampered by the limited availability of appropriate small molecule inhibitors. Using a fluorescence polarization-based screen, we identify Mad2 inhibitor-1 (M2I-1), the first small molecule inhibitor targeting the binding of Mad2 to Cdc20, an essential protein-protein interaction (PPI) within the SAC. Based on computational and biochemical analyses, we propose that M2I-1 disturbs conformational dynamics of Mad2 critical for complex formation with Cdc20. Cellular studies revealed that M2I-1 weakens the SAC response, indicating that the compound might be active in cells. Thus, our study identifies the SAC specific complex formation between Mad2 and Cdc20 as a protein-protein interaction that can be targeted by small molecules.
Spatio-temporal control of cellular uptake achieved by photoswitchable cell-penetrating peptides
(2015)
The selective uptake of compounds into specific cells of interest is a major objective in cell biology and drug delivery. By incorporation of a novel, thermostable azobenzene moiety we generated peptides that can be switched optically between an inactive state and an active, cell-penetrating state with excellent spatio-temporal control.
Zweimal Kyros
(2015)
«Kyros» taucht als Fürstenname dreimal in der Überlieferung des Perserreiches auf. Der Historiker Xenophon von Athen (427–ca. 355 v. Chr.) hat in seinen Schriften über zwei Träger dieses Namens berichtet und sie durchaus unterschiedlich bewertet: Kyros II. («der Große»), Mehrer des Reiches, sowie ein Jahrhundert später Kyros, Sohn des Dareios und jüngerer Bruder des Perserkönigs Artaxerxes II. Der ältere Kyros ist namengebender Protagonist eines Fürstenspiegels (der Kyropädie), wird also grundsätzlich positiv und als ein Vorbild für andere dargestellt. Am erfolglosen Kampf des jüngeren Kyros um die Krone des Perserreichs hatte Xenophon als Offizier griechischer Söldner selbst teilgenommen. Aus dem Vergleich von Darstellung und Bewertung der beiden Fürsten lassen sich die Ansprüche Xenophons an einen idealen Herrscher ableiten, was hier unternommen werden soll. Zugleich ermöglichen diese Ergebnisse, Xenophon als Historiker und politischen Denker in der zeitgenössischen Debatte um die beste Staatsform einzubetten.
The United Nations Security Council (UNSC) is one of the most important multilateral institutions having the ambition to shape global governance and the only organ of the global community that can adopt legally binding resolutions for the maintenance of international peace and security and, if necessary, authorize the use of force. Created in the aftermath of World War II by its victors, the UNSC’s constellation looks increasingly anachronistic, however, in light of the changing global distribution of power. Adapting the institutional structure and decision-making procedures of the UNSC has proven to be one of the most difficult challenges of the last decades, while it is the institution that has probably been faced with the most vociferous calls for reform. Although there have been changes to the informal ways in which outside actors are drawn into the UNSC’s work and activities, many of the major players in the current international system seem to be deprived from equal treatment in its core patterns of decision-making. Countries such as Brazil, Germany, India and Japan, alongside emerging African nations such as Nigeria and South Africa, are among the states eager to secure permanent representation on the Council. By comparison, selected BRICS countries, China and Russia - in contrast to their role in other multilateral institutions - are permanent members of the UNSC and with this, have been “insiders” for a long time. This renders the situation of the UNSC different from global institutions, in which traditionally, Western powers have dominated the agenda.
Krise der deutschen Nation?
(2015)
Let A be a nonlinear differential operator on an open set X in R^n and S a closed subset of X. Given a class F of functions in X, the set S is said to be removable for F relative to A if any weak solution of A (u) = 0 in the complement of S of class F satisfies this equation weakly in all of X. For the most extensively studied classes F we show conditions on S which guarantee that S is removable for F relative to A.
The role of knowledge in the policy process remains a central theoretical puzzle in policy analysis and political science. This article argues that an important yet missing piece of this puzzle is the systematic exploration of the political use of policy knowledge. While much of the recent debate has focused on the question of how the substantive use of knowledge can improve the quality of policy choices, our understanding of the political use of knowledge and its effects in the policy process has remained deficient in key respects. A revised conceptualization of the political use of knowledge is introduced that emphasizes how conflicting knowledge can be used to contest given structures of policy authority. This allows the analysis to differentiate between knowledge creep and knowledge shifts as two distinct types of knowledge effects in the policy process. While knowledge creep is associated with incremental policy change within existing policy structures, knowledge shifts are linked to more fundamental policy change in situations when the structures of policy authority undergo some level of transformation. The article concludes by identifying characteristics of the administrative structure of policy systems or sectors that make knowledge shifts more or less likely.
Prozessorientierte Didaktik
(2015)
n diesem Beitrag finden Sie ein von mir entwickeltes Konzept zum Lehren und Lernen in der Schule1. Ich nenne dieses Konzept prozessorientierte Didaktik. Ich habe die Hoffnung, gemeinsam mit Ihnen als Lehrer oder Lehramtsstudierende, aber auch mit Eltern, Wissenschaftlern, Experten für Bildung und Schülern, einen Beitrag zur Verbesserung unserer Schulpraxis zu leisten. Dass Schule sich bereits im Wandel befindet und wunderbar gelingen kann, sieht man beispielsweise an den Preisträgern des Deutschen Schulpreises. Leider sind diese Schulen immer noch in der Minderheit. Dieses Verhältnis umzukehren ist eine unserer größten Bildungsaufgaben für die nächsten Jahrzehnte.
It is well established in language acquisition research that monolingual children and adult second language learners misinterpret sentences with the universal quantifier every and make quantifier-spreading errors that are attributed to a preference for a match in number between two sets of objects. The present Visual World eye-tracking study tested bilingual heritage Russian–English adults and investigated how they interpret of sentences like Every alligator lies in a bathtub in both languages. Participants performed a sentence–picture verification task while their eye movements were recorded. Pictures showed three pairs of alligators in bathtubs and two extra objects: elephants (Control condition), bathtubs (Overexhaustive condition), or alligators (Underexhaustive condition). Monolingual adults performed at ceiling in all conditions. Heritage language (HL) adults made 20% q-spreading errors, but only in the Overexhaustive condition, and when they made an error they spent more time looking at the two extra bathtubs during the Verb region. We attribute q-spreading in HL speakers to cognitive overload caused by the necessity to integrate conflicting sources of information, i.e. the spoken sentences in their weaker, heritage, language and attention-demanding visual context, that differed with respect to referential salience.
It is well established in language acquisition research that monolingual children and adult second language learners misinterpret sentences with the universal quantifier every and make quantifier-spreading errors that are attributed to a preference for a match in number between two sets of objects. The present Visual World eye-tracking study tested bilingual heritage Russian-English adults and investigated how they interpret of sentences like Every alligator lies in a bathtub in both languages. Participants performed a sentence-picture verification task while their eye movements were recorded. Pictures showed three pairs of alligators in bathtubs and two extra objects: elephants (Control condition), bathtubs (Overexhaustive condition), or alligators (Underexhaustive condition). Monolingual adults performed at ceiling in all conditions. Heritage language (HL) adults made 20% q-spreading errors, but only in the Overexhaustive condition, and when they made an error they spent more time looking at the two extra bathtubs during the Verb region. We attribute q-spreading in HL speakers to cognitive overload caused by the necessity to integrate conflicting sources of information, i.e. the spoken sentences in their weaker, heritage, language and attention-demanding visual context, that differed with respect to referential salience.
Permafrost inundated since the last glacial maximum is degrading, potentially releasing trapped or stabilized greenhouse gases, but few observations of the depth of ice-bonded permafrost (IBP) below the seafloor exist for most of the arctic continental shelf. We use spectral ratios of the ambient vibration seismic wavefield, together with estimated shear wave velocity from the dispersion curves of surface waves, for estimating the thickness of the sediment overlying the IBP. Peaks in spectral ratios modeled for three-layered 1-D systems correspond with varying thickness of the unfrozen sediment. Seismic receivers were deployed on the seabed around Muostakh Island in the central Laptev Sea, Siberia. We derive depths of the IBP between 3.7 and 20.7m15%, increasing with distance from the shoreline. Correspondence between expected permafrost distribution, modeled response, and observational data suggests that the method is promising for the determination of the thickness of unfrozen sediment.
Many foresight studies concentrate on technological foresight and its impact at the organizational level. However, often these studies overlook the soft factor of employee competences which is critical to adopting technological and organizational changes and to developing the necessary innovation capabilities. This study investigates the theoretical and methodological underdeveloped relationship between technological innovation and social initiated change and the impact on individual competences in a dynamic sector. The setting of our study is the turbulent creative industries as a whole, where creative and artistic expression merges with changing technological progress. In a scenario study we mainly conducted in 2010, we developed a scenario model for competences to combine individual competences with a scenario approach to investigate how competences are important to the sector shift or need to be enhanced in the future. We use primary qualitative data from expert interviews and workshops and secondary data from industry reports to identify thirty-seven influence factors. An influence matrix calculation and a cluster analysis are used to project three different scenarios presenting how future developments of the creative industries will influence the competences needed for creative occupations. Now, five years later, we reflect the accuracy of the developed scenarios via a comparison of today's situation with the situation in the scenarios. We discuss theoretical contributions for the foresight literature and practical implementations for the future of work in general, and in particular for the creative industries case. (C) 2015 Elsevier Inc. All rights reserved.
Parental effects (PE) can be adaptive and improve offspring performance when parents and offspring experience similar environmental conditions. However, it is unknown whether adaptive PE exist also in habitats where such similarity is unlikely due to strong temporal variation. In particular, we do not know whether PE can adapt offspring to fluctuating levels of neighbour competition in such habitats. Here, we tested for adaptive PE in terms of two key environmental factors in a semi-arid annual system, competition and drought. While rainfall was stochastic in the study site, the competitive environment was partly predictable: higher plant densities followed after favourable (rainy) years due to high seed production. We therefore expected PE to adapt the offspring's competitive ability to these (predictable) fluctuations in plant densities, rather than to adapt the offspring's drought tolerance to the (unpredictable) occurrence of intensified drought. Parental plants of Biscutella didyma, an annual Brassicaceae, were raised under favourable watering and under drought conditions. Offspring performance was then tested under a full-factorial combination of two neighbour regimes and six watering levels in the glasshouse. Offspring of parents grown under favourable conditions were stronger competitors. This was associated with a small shift in phenology but not with higher parental seed provisioning. Offspring from parents grown under drought showed no improved drought tolerance. Moreover, no PE were detectable when offspring were grown without neighbours. Our results suggest a novel path of adaptive PE: higher competitive ability was induced in offspring that were more likely to experience high neighbour densities. Together with the lack of adaptive PE towards drought tolerance, this emphasizes that a correlation between parental and offspring environment is crucial for adaptive PE to evolve. Our results also call for the inclusion of competitive effects in future PE studies.Synthesis. This study demonstrates the important role of adaptive PE for plant fitness (regarding competition) but also their limits (regarding drought) in temporally variable environments, based on the predictability of the respective environmental factor.
Warum Religion?
(2015)
Die meisten Religionen versprechen ein Leben nachdem Tod, in dem es glücklicher oder gerechter oder sonst wie besser zugehen soll als auf der Erde. Wie schön wäre es, wenn wir wirklich auf ein ewiges Leben in der Gegenwart Gottes oder auf ein neues Leben in einem unverbrauchten Körper hoffen könnten! Wir könnten gelassener mit irdischem Scheitern umgehen und eher loslassen, wenn wir sicher sein könnten, dass alles, was uns hier widerfährt, nur ein Übergang in eine bessere Existenz ist. Aber lenken die Religionen mit solchen Versprechungen nicht nur von irdischen Missständen ab? Mit solchen Argumenten sind die Religionen als Opium des Volkes in Sippenhaft genommen worden. Jenseits dessen stellt sich das Problem des szientistischen Zweifels. Wie soll mich eine religiöse Überzeugung durch mein Leben tragen, wenn die Überzeugung nicht überzeugend ist? Ist es wirklich glaubwürdig, dass Jesus von Nazareth nach drei Tagen im Grab wieder auferstanden sein soll? Wenn ich das nicht glauben kann, kann ich auch nicht an meine eigene Auferstehung glauben. Wohl kaum eine andere Religionsphilosophie stellt eine so enge Beziehung zwischen religiösem Glauben und irdischem Wohlergehen her wie die des amerikanischen Pragmatismus: Bei William James heißt es ausdrücklich, dass ein religiöser Glaube das Leben »leicht und glücklich« machen könne. Und kaum eine Religionsphilosophie benennt so deutlich das Problem des szientistischen Zweifels. Im ersten Teil des Buches, Religion, pragmatisch betrachtet, befassen sich Johannes Ev. Hafner, Christian Thies und Christoph Türcke mit der Funktion von Religion in unserer Gesellschaft und in unseren konkreten Lebensvollzügen. Im zweiten Teil stellen Michael Blume, Matthias Jung, Ludwig Nagl und Marie-Luise Raters Positionen der pragmatistischen Religionsphilosophie auf den Prüfstand.
Aims. To explore the origin of high-velocity gas in the direction of the Large Magellanic Cloud, (LMC) we analyze absorption lines in the ultraviolet spectrum of a Galactic halo star that is located in front of the LMC at d = 9.2(-7.2)(+4.1) kpc distance.
Methods. We study the velocity-component structure of low and intermediate metal ions (CII, SiII, SiIII) in the spectrum of RXJ0439.8-6809, as obtained with the Cosmic Origins Spectrograph (COS) onboard the Hubble Space Telescope (HST), and measure equivalent widths and column densities for these ions. We supplement our COS data with a Far-Ultraviolet Spectroscopic Explorer (FUSE) spectrum of the nearby LMC star Sk-69 59 and with Hi 21 cm data from the Leiden-Argentina-Bonn (LAB) survey.
Results. Metal absorption toward RXJ0439.8-6809 is unambiguously detected in three different velocity components near v(LSR) = 0, + 60, and + 150 km s(-1). The presence of absorption proves that all three gas components are situated in front of the star, thus located in the disk and inner halo of the Milky Way. For the high-velocity cloud (HVC) at v(LSR) = + 150 km s(-1), we derive an oxygen abundance of [O/H] = -0.63 (similar to 0.2 solar) from the neighboring Sk-69 59 sight line, in accordance with previous abundance measurements for this HVC. From the observed kinematics we infer that the HVC hardly participates in the Galactic rotation.
Conclusions. Our study shows that the HVC toward the LMC represents a Milky Way halo cloud that traces low column density gas with relatively low metallicity. We rule out scenarios in which the HVC represents material close to the LMC that stems from a LMC outflow.
Don't worry - be happy?
(2015)
We attempt to clarify a great deal of confusion in the literature on what a passive is, and what counts as a passive in different languages. We do this through a detailed investigation of what has been identified as a passive in Vietnamese, sentences with the morphemes bi and duoc. We also compare these to Mandarin Chinese bei. We show that these morphemes are not passive at all: like English auxiliaries, they may occur with either an active complement or a passive one. We clarify this point and what it means to be a passive. Second, sentences with these morphemes and the corresponding sentences without them are truth-conditionally equivalent. We show that the extra meaning they convey is a type of projective, or not-at-issue, meaning that is separate from the at-issue content of the sentence. We provide a detailed syntactic and semantic analysis of Vietnamese, and give arguments for this analysis. We propose that there is no movement in Vietnamese, but there is in Chinese, and this difference accounts for differences between the two languages. We also clarify what agent-oriented adverbs of the 'deliberately' type show, and draw conclusions about English get passives and tough constructions. (C) 2015 Elsevier B.V. All rights reserved.
The Strange-tailed Tyrant Alectrurus risora (Aves: Tyrannidae) is an endemic species of southern South American grasslands that suffered a 90% reduction of its original distribution due to habitat transformation. This has led the species to be classified as globally Vulnerable. By the beginning of the last century, populations were partially migratory and moved south during the breeding season. Currently, the main breeding population inhabits the Ibera wetlands in the province of Corrientes, north-east Argentina, where it is resident all year round. There are two remaining small populations in the province of Formosa, north-east Argentina, and in southern Paraguay, which are separated from the main population by the Parana-Paraguay River and its continuous riverine forest habitat. The populations of Corrientes and Formosa are separated by 300 km and the grasslands between populations are non-continuous due to habitat transformation. We used mtDNA sequences and eight microsatellite loci to test if there were evidences of genetic isolation between Argentinean populations. We found no evidence of genetic structure between populations (Phi(ST) = 0.004, P = 0.32; Fst = 0.01, P = 0.06), which can be explained by either retained ancestral polymorphism or by dispersal between populations. We found no evidence for a recent demographic bottleneck in nuclear loci. Our results indicate that these populations could be managed as a single conservation unit on a regional scale. Conservation actions should be focused on preserving the remaining network of areas with natural grasslands to guarantee reproduction, dispersal and prevent further decline of populations.
The Strange-tailed Tyrant Alectrurus risora (Aves: Tyrannidae) is an endemic species of southern South American grasslands that suffered a 90% reduction of its original distribution due to habitat transformation. This has led the species to be classified as globally Vulnerable. By the beginning of the last century, populations were partially migratory and moved south during the breeding season. Currently, the main breeding population inhabits the Ibera wetlands in the province of Corrientes, north-east Argentina, where it is resident all year round. There are two remaining small populations in the province of Formosa, north-east Argentina, and in southern Paraguay, which are separated from the main population by the Parana-Paraguay River and its continuous riverine forest habitat. The populations of Corrientes and Formosa are separated by 300 km and the grasslands between populations are non-continuous due to habitat transformation. We used mtDNA sequences and eight microsatellite loci to test if there were evidences of genetic isolation between Argentinean populations. We found no evidence of genetic structure between populations (Phi(ST) = 0.004, P = 0.32; Fst = 0.01, P = 0.06), which can be explained by either retained ancestral polymorphism or by dispersal between populations. We found no evidence for a recent demographic bottleneck in nuclear loci. Our results indicate that these populations could be managed as a single conservation unit on a regional scale. Conservation actions should be focused on preserving the remaining network of areas with natural grasslands to guarantee reproduction, dispersal and prevent further decline of populations.
Nero nuntiis magis et rumoribus quam armis depulsus. Der römische Geschichtsschreiber Tacitus konstatierte in den Historien, Kaiser Nero sei „mehr durch Botschaften und Gerüchte gestürzt worden als durch Waffengewalt“ (hist. 1,89,2). Laut der antiken Quellen redete die plebs urbana tatsächlich mit unbändigem Interesse über den princeps und diskutierte Gerüchte, die Neros Verfehlungen als Schutzherr Roms thematisierten oder ihn gar der Brandstiftung bezichtigten – das Bild des verrückten Kaisers, der Leier spielend seine Freude über das brennende Rom ausdrückt, dient weithin als anschauliches Beispiel eines Tyrannen.
Diese Arbeit überprüft die genannte taciteische These auf Schlüssigkeit. Dazu muss die komplexe Konstellation der Herrschaft Neros sowie seines Untergangs, in Hinblick auf die Wirkungsweise der Gerüchte, dargelegt und analysiert werden. Es werden anfangs elementare Fragen der geschichtswissenschaftlichen Forschung zu Nero und zum frühen Prinzipat behandelt: Über welches Ansehen und Handlungspotential verfügte die plebs urbana? Wodurch wurde die Herrschaft des Kaisers legitimiert und auf welche Gruppen zielte Neros Herrschaftspropaganda ab?
Im Anschluss erläutert und analysiert der Verfasser die Funktionen des Gerüchts als Mittel der politischen Meinungsbildung für die Aristokratie und die hauptstädtische plebs. Der Einfluss der üblen Nachrede auf die Herrschaft Neros wird durch die Schilderung dreier kennzeichnender Gerüchtekomplexe analysiert und führt schließlich zu der Frage, ob tatsächlich die fama zum Sturz des Kaisers führte oder vielmehr die vernachlässigte Heeresklientel an den Reichsgrenzen die entscheidenden Entwicklungen vorantrieb.
The high-latitudinal thermospheric processes driven by the solar wind and Interplanetary Magnetic Field (IMF) interaction with the Earth magnetosphere are highly variable parts of the complex dynamic plasma environment, which represent the coupled Magnetosphere – Ionosphere – Thermosphere (MIT) system. The solar wind and IMF interactions transfer energy to the MIT system via reconnection processes at the magnetopause. The Field Aligned Currents (FACs) constitute the energetic links between the magnetosphere and the Earth ionosphere. The MIT system depends on the highly variable solar wind conditions, in particular on changes of the strength and orientation of the IMF.
In my thesis, I perform an investigation on the physical background of the complex MIT system using the global physical - numerical, three-dimensional, time-dependent and self-consistent Upper Atmosphere Model (UAM). This model describes the thermosphere, ionosphere, plasmasphere and inner magnetosphere as well as the electrodynamics of the coupled MIT system for the altitudinal range from 80 (60) km up to the 15 Earth radii.
In the present study, I developed and investigated several variants of the high-latitudinal electrodynamic coupling by including the IMF dependence of FACs into the UAM model. For testing, the various variants were applied to simulations of the coupled MIT system for different seasons, geomagnetic activities, various solar wind and IMF conditions. Additionally, these variants of the theoretical model with the IMF dependence were compared with global empirical models. The modelling results for the most important thermospheric parameters like neutral wind and mass density were compared with satellite measurements. The variants of the UAM model with IMF dependence show a good agreement with the satellite observations. In comparison with the empirical models, the improved variants of the UAM model reproduce a more realistic meso-scale structures and dynamics of the coupled MIT system than the empirical models, in particular at high latitudes. The new configurations of the UAM model with IMF dependence contribute to the improvement of space weather prediction.
Island biotas emerge from the interplay between colonisation, speciation and extinction and are often the scene of spectacular adaptive radiations. A common assumption is that insular diversity is at a dynamic equilibrium, but for remote islands, such as Hawaii or Galápagos, this idea remains untested. Here, we reconstruct the temporal accumulation of terrestrial bird species of the Galápagos using a novel phylogenetic method that estimates rates of biota assembly for an entire community. We show that species richness on the archipelago is in an ascending phase and does not tend towards equilibrium. The majority of the avifauna diversifies at a slow rate, without detectable ecological limits. However, Darwin's finches form an exception: they rapidly reach a carrying capacity and subsequently follow a coalescent-like diversification process. Together, these results suggest that avian diversity of remote islands is rising, and challenge the mutual exclusivity of the non-equilibrium and equilibrium ecological paradigms.
Island biotas emerge from the interplay between colonisation, speciation and extinction and are often the scene of spectacular adaptive radiations. A common assumption is that insular diversity is at a dynamic equilibrium, but for remote islands, such as Hawaii or Galápagos, this idea remains untested. Here, we reconstruct the temporal accumulation of terrestrial bird species of the Galápagos using a novel phylogenetic method that estimates rates of biota assembly for an entire community. We show that species richness on the archipelago is in an ascending phase and does not tend towards equilibrium. The majority of the avifauna diversifies at a slow rate, without detectable ecological limits. However, Darwin's finches form an exception: they rapidly reach a carrying capacity and subsequently follow a coalescent-like diversification process. Together, these results suggest that avian diversity of remote islands is rising, and challenge the mutual exclusivity of the non-equilibrium and equilibrium ecological paradigms.
Editorial (Dr. Roswitha Lohwaßer) ; Erwartungen und Ziele. Fragen der kentron-Redaktion an die Mitglieder der Versammlung des Zentrums für Lehrerbildung und Bildungsforschung (Prof. Dr. Bernd Meier, Prof. Dr. Agi Schründer, Prof. Dr. Andreas Borowski, Prof. Dr. Erin Gerlach, Matthias Schall, Prof. Dr. Martin Leubner, Prof. Dr. Bernd Schmidt) ; PSI - Potsdam. Professionalisierung - Schulpraktische Studien - Inklusion: Potsdamer Modell der Lehrerbildung (Dr. Jolanda Hermanns) ; Professionalisierung. Verbesserung des Professionswissens von Lehramtsstudierenden durch Integration von fachwissenschaftlichen und fachdidaktischen Ausbildungsanteilen (Dr. Ingrid Glowinksi) ; Schulpraktische Studien. Stärkung des Kompetenzerwerbs bei der Integration schulpraktischer Elemente (Prof. Dr. Andreas Borowski) ; Inklusion und Heterogenität (Prof. Dr. Antje Ehlert)
Frankreich 1958: Der Algerienkrieg eskaliert, die links-liberale Regierung implodiert und reicht die Macht an General Charles de Gaulle weiter. Der hebt im Oktober die V. Republik aus der Taufe - und die französische Linke gesteht damit ihre Ohnmacht ein. Die Sozialisten haben den Machtantritt des konservativen Generals nicht verhindert, sondern diesen sogar mit angezettelt. Auch die Kommunisten sind isoliert und kämpfen mit dem stalinistischen Erbe. Einige Genossen erkennen ihre sozialistische Bewegung nicht wieder und beschließen, eine neue linke Bewegung aufbauen. Sie wollen de Gaulle und den Krieg offen bekämpfen, "veraltete" linke Ideologien über Bord werfen und ein "Labor" für neues linkes Denken schaffen. Parteimitglieder der Altkommunisten, Sozialisten und Trotzkisten, aber auch Künstler, Philosophen und Schriftsteller wurden Teil dieser heterogenen Bewegung, die heute als Neue Linke bezeichnet wird. Der interessierte Leser begreift nun die Ideengeschichte dieser Neuen französischen Linken, die nicht nur einen starken Einfluss auf die Ereignisse um 1968 in Frankreich ausübte, sondern deren Ansätze noch bis heute im linken Spektrum, inner- wie außerparteilich, für Diskussionsstoff sorgen.
lower development is controlled by the action of key regulatory transcription factors of the MADS-domain family. The function of these factors appears to be highly conserved among species based on mutant phenotypes. However, the conservation of their downstream processes is much less well understood, mostly because the evolutionary turnover and variation of their DNA-binding sites (BSs) among plant species have not yet been experimentally determined. Here, we performed comparative ChIP (chromatin immunoprecipitation)-seq experiments of the MADS-domain transcription factor SEPALLATA3 (SEP3) in two closely related Arabidopsis species: Arabidopsis thaliana and A. lyrata which have very similar floral organ morphology. We found that BS conservation is associated with DNA sequence conservation, the presence of the CArG-box BS motif and on the relative position of the BS to its potential target gene. Differences in genome size and structure can explain that SEP3 BSs in A. lyrata can be located more distantly to their potential target genes than their counterparts in A. thaliana. In A. lyrata, we identified transposition as a mechanism to generate novel SEP3 binding locations in the genome. Comparative gene expression analysis shows that the loss/gain of BSs is associated with a change in gene expression. In summary, this study investigates the evolutionary dynamics of DNA BSs of a floral key-regulatory transcription factor and explores factors affecting this phenomenon.
Veröffentlicht wird die Textfassung eines Vortrages, welcher am 16. April 2015 auf dem 9. Konsortialtag des Friedrich-Althoff-Konsortium e.V. in Potsdam gehalten wurde. Hintergrund des Vortrages war die aktive Auseinandersetzung der Institution mit vorhandenen Lizenzrechten. Auf dieser Basis wurde ein Workflow zur Identifizierung von Publikationen für die Zweitveröffentlichung erarbeitet. Der vorgestellte Workflow umfasst sieben Schritte, von denen fünf näher erläutert und mit Beispielen einzelner Lizenzen/Verlage unterlegt wurden.
Welcher Diskurs wird um Jungenarbeit als geschlechtssensible pädagogische Arbeit mit männlichen Kindern und Jugendlichen und deren Umsetzung in kurzzeitpädagogischen außerunterrichtlichen Angeboten geführt? Thomas Viola Rieske geht dieser Frage nach und legt nahe, dass Normativität als unausweichlicher Bestandteil pädagogischer Praxis anerkannt und zugleich kritisch reflektiert werden muss, um Jungen in ihrer Entwicklung stärken zu können. Er diskutiert die verschiedenen geschlechtertheoretischen und pädagogischen Grundpositionen, die im Fachdiskurs über Jungenarbeit bestehen und untersucht die Umsetzung von Jungenarbeit. Er zeigt auf, dass die Teilnehmer der beobachteten Jungenseminare einerseits zu einem partnerschaftlichen, normenkritischen und direkten Kontakt mit sich und anderen befähigt werden, andererseits aber auch Zuschreibungen, Grenzüberschreitungen und ein Übergehen ihrer Bedürfnisse erfahren.
Der Businessplan
(2015)
Entrepreneurial Marketing
(2015)
Finanzplanung
(2015)
Symbolische Bedeutungen sind für den Erfolg von Marken heutzutage unerlässlich, denn Produkte lassen sich in postmodernen Konsumgesellschaften meist nicht mehr ausschließlich durch funktionale Leistungsunterschiede vom Wettbewerb differenzieren. Vielmehr sollten Marken zudem über einen signifikanten Zusatznutzen verfügen, welcher grundsätzlich sozialpsychologischer Natur ist. Dieser in der Markenpersönlichkeit verdichtete symbolische Kern spricht die zentralen menschlichen Bedürfnisse nach Selbstdefinition und Selbstausdruck an, da Individuen sich als „soziale Tiere“ grundlegend über die Zugehörigkeit zu sozialen Gruppen definieren. Einstellungen relevanter Bezugspersonen zum eigenen Selbstbild sind fundamental für die persönliche Standortbestimmung. Genauso leiten Konsumenten symbolische Markenbedeutungen von ihren Bezugsgruppen ab. Individuen evaluieren demnach permanent, inwiefern die wahrgenommene Markenpersönlichkeit zum aktuellen bzw. angestrebten Selbstkonzept passt. Diese dargestellten Phänomene unterliegen dem kulturellen Einfluss der jeweiligen Gesellschaft, in der sie sich herausbilden. Die symbolischen Bedeutungen von Selbstbildern und Marken formen sich also zwischen Kulturen bspw. unter unterschiedlich stark geartetem sozialem Einfluss.
Die Untersuchung geht demnach der Frage auf den Grund, inwiefern die soziale Umgebung Einfluss auf die Wahrnehmung symbolischer Markenaspekte und deren wahrgenommener Kongruenz zum Selbstkonzept von Konsumenten ausübt. Darüber hinaus eruiert der Verfasser intensiv, ob und in welchem Umfang die Empfänglichkeit für die verschiedenen Facetten sozialen Einflusses von der Enkulturation des Konsumenten abhängt.
Es werden somit Forderungen aus Marketing- und Konsumentenverhaltensforschung adressiert, wonach die sozialen sowie die kulturellen Einflusskomponenten stärker zu berücksichtigen sind, um ein vollständigeres Bild von Konsumentscheidungen zu erlangen.
Die zahlreichen theoretischen und empirischen Erkenntnisse der Studie weisen auf wichtige Implikationen für die intra- und interkulturelle Segmentierung von Zielgruppen hin. Empfehlungen für die strategische Positionierung von symbolischen Markenkernen und deren Kommunikation werden ebenfalls geliefert.
In this work we present a CMOS high frequency direct immunosensor operating at 6 GHz (C-band) for label free determination of creatinine. The sensor is fabricated in standard 0.13 μm SiGe:C BiCMOS process. The report also demonstrates the ability to immobilize creatinine molecules on a Si3N4 passivation layer of the standard BiCMOS/CMOS process, therefore, evading any further need of cumbersome post processing of the fabricated sensor chip. The sensor is based on capacitive detection of the amount of non-creatinine bound antibodies binding to an immobilized creatinine layer on the passivated sensor. The chip bound antibody amount in turn corresponds indirectly to the creatinine concentration used in the incubation phase. The determination of creatinine in the concentration range of 0.88–880 μM is successfully demonstrated in this work. A sensitivity of 35 MHz/10 fold increase in creatinine concentration (during incubation) at the centre frequency of 6 GHz is gained by the immunosensor. The results are compared with a standard optical measurement technique and the dynamic range and sensitivity is of the order of the established optical indication technique. The C-band immunosensor chip comprising an area of 0.3 mm2 reduces the sensing area considerably, therefore, requiring a sample volume as low as 2 μl. The small analyte sample volume and label free approach also reduce the experimental costs in addition to the low fabrication costs offered by the batch fabrication technique of CMOS/BiCMOS process.
In this work we present a CMOS high frequency direct immunosensor operating at 6 GHz (C-band) for label free determination of creatinine. The sensor is fabricated in standard 0.13 μm SiGe:C BiCMOS process. The report also demonstrates the ability to immobilize creatinine molecules on a Si3N4 passivation layer of the standard BiCMOS/CMOS process, therefore, evading any further need of cumbersome post processing of the fabricated sensor chip. The sensor is based on capacitive detection of the amount of non-creatinine bound antibodies binding to an immobilized creatinine layer on the passivated sensor. The chip bound antibody amount in turn corresponds indirectly to the creatinine concentration used in the incubation phase. The determination of creatinine in the concentration range of 0.88–880 μM is successfully demonstrated in this work. A sensitivity of 35 MHz/10 fold increase in creatinine concentration (during incubation) at the centre frequency of 6 GHz is gained by the immunosensor. The results are compared with a standard optical measurement technique and the dynamic range and sensitivity is of the order of the established optical indication technique. The C-band immunosensor chip comprising an area of 0.3 mm2 reduces the sensing area considerably, therefore, requiring a sample volume as low as 2 μl. The small analyte sample volume and label free approach also reduce the experimental costs in addition to the low fabrication costs offered by the batch fabrication technique of CMOS/BiCMOS process.
Double cyclization of short linear peptides obtained by solid phase peptide synthesis was used to prepare bridged bicyclic peptides (BBPs) corresponding to the topology of bridged bicyclic alkanes such as norbornane. Diastereomeric norbornapeptides were investigated by 1H-NMR, X-ray crystallography and CD spectroscopy and found to represent rigid globular scaffolds stabilized by intramolecular backbone hydrogen bonds with scaffold geometries determined by the chirality of amino acid residues and sharing structural features of β-turns and α-helices. Proteome profiling by capture compound mass spectrometry (CCMS) led to the discovery of the norbornapeptide 27c binding selectively to calmodulin as an example of a BBP protein binder. This and other BBPs showed high stability towards proteolytic degradation in serum.
Double cyclization of short linear peptides obtained by solid phase peptide synthesis was used to prepare bridged bicyclic peptides (BBPs) corresponding to the topology of bridged bicyclic alkanes such as norbornane. Diastereomeric norbornapeptides were investigated by 1H-NMR, X-ray crystallography and CD spectroscopy and found to represent rigid globular scaffolds stabilized by intramolecular backbone hydrogen bonds with scaffold geometries determined by the chirality of amino acid residues and sharing structural features of β-turns and α-helices. Proteome profiling by capture compound mass spectrometry (CCMS) led to the discovery of the norbornapeptide 27c binding selectively to calmodulin as an example of a BBP protein binder. This and other BBPs showed high stability towards proteolytic degradation in serum.
Dieses Lehrbuch informiert umfassend über die examensrelevanten Straftatbestände des StGB, die Vermögen, Eigentum oder sonstige Vermögensgüter schützen. Der Text bereitet den Stoff systematisch auf und hebt dabei schwierige und umstrittene Einzelfragen durch ausführliche Darstellung der dazu vertretenen Meinungen deutlich hervor. Unterstützt wird der Lernprozess mittels zahlreicher Fallbeispiele mit Lösungshinweisen, die dem Benutzer Gelegenheit zu aktiven Übungen an Strafrechtsfällen geben. Der Leser sollte daher zunächst versuchen, die Fälle selbst zu lösen und danach den Text weiter lesen. Auch die am Ende jedes Kapitels gestellten „Kontrollfragen“ sind eine Aufforderung zur Überprüfung des Lernerfolges und gegebenenfalls Wiederholung der Lektüre. Über den Bereich des Besonderen Teils hinausgehende Repetitionseffekte verspricht das Buch dem Leser auf Grund der vielfältigen Bezugnahmen auf das Allgemeine Strafrecht, beispielsweise zu Fragen von Täterschaft und Teilnahme oder Versuch, Vollendung und Beendigung.
Entsorgt und ausgeblendet
(2015)
Die Kluft zwischen Ost- und Westdeutschen ist in den vergangenen Jahren nicht schmaler geworden. Bis heute sind Ostdeutsche nur selten in Führungspositionen in Wirtschaft, Politik und Medien anzutreffen. Offensichtlich ist die Herstellung der inneren Einheit ein schwieriger, langwieriger Prozess der Annäherung, der womöglich nie vollständig vollzogen werden kann. Diesem Prozess nachzugehen und zu zeigen, wie sich Eliten vor dem Hintergrund gesellschaftlicher Umbrüche positionieren, welche Voraussetzungen die beteiligten Generationen und Elitenvertreter in Ost- und Westdeutschland mitbrachten, in welcher Form sie tangiert waren und welche medialen Perspektiven sich daran knüpfen, ist Ziel dieses Buches. Denn der Umgang mit den ostdeutschen Eliten berührt unsere Zukunft.
Arsenic-containing fatty acids are a group of fat-soluble arsenic species (arsenolipids) which are present in marine fish and other seafood. Recently, it has been shown that arsenic-containing hydrocarbons, another group of arsenolipids, exert toxicity in similar concentrations comparable to arsenite although the toxic modes of action differ. Hence, a risk assessment of arsenolipids is urgently needed. In this study the cellular toxicity of a saturated (AsFA 362) and an unsaturated (AsFA 388) arsenic-containing fatty acid and three of their proposed metabolites (DMAV, DMAPr and thio-DMAPr) were investigated in human liver cells (HepG2). Even though both arsenic-containing fatty acids were less toxic as compared to arsenic-containing hydrocarbons and arsenite, significant effects were observable at μM concentrations. DMAV causes effects in a similar concentration range and it could be seen that it is metabolised to its highly toxic thio analogue thio-DMAV in HepG2 cells. Nevertheless, DMAPr and thio-DMAPr did not exert any cytotoxicity. In summary, our data indicate that risks to human health related to the presence of arsenic-containing fatty acids in marine food cannot be excluded. This stresses the need for a full in vitro and in vivo toxicological characterisation of these arsenolipids.
Arsenic-containing fatty acids are a group of fat-soluble arsenic species (arsenolipids) which are present in marine fish and other seafood. Recently, it has been shown that arsenic-containing hydrocarbons, another group of arsenolipids, exert toxicity in similar concentrations comparable to arsenite although the toxic modes of action differ. Hence, a risk assessment of arsenolipids is urgently needed. In this study the cellular toxicity of a saturated (AsFA 362) and an unsaturated (AsFA 388) arsenic-containing fatty acid and three of their proposed metabolites (DMAV, DMAPr and thio-DMAPr) were investigated in human liver cells (HepG2). Even though both arsenic-containing fatty acids were less toxic as compared to arsenic-containing hydrocarbons and arsenite, significant effects were observable at μM concentrations. DMAV causes effects in a similar concentration range and it could be seen that it is metabolised to its highly toxic thio analogue thio-DMAV in HepG2 cells. Nevertheless, DMAPr and thio-DMAPr did not exert any cytotoxicity. In summary, our data indicate that risks to human health related to the presence of arsenic-containing fatty acids in marine food cannot be excluded. This stresses the need for a full in vitro and in vivo toxicological characterisation of these arsenolipids.
Innerhalb der EU wird die Fusionskontrolle auf zwei vertikal nachgelagerten Ebenen durchgeführt, der europäischen und der nationalen Instanz. Da beide Ebenen nicht unverbunden sind, ergibt sich ein mehrdimensionales Kompetenzproblem. Die Fusionskontrollkompetenzen sind vertikal (europäische versus mitgliedstaatliche Ebene) und horizontal (mitgliedstaatliche Ebene) abgegrenzt. Während auf vertikaler Ebene konkurrierende Zuständigkeiten ausgeschlossen sind, sind horizontal Überlappungen möglich.
Die Arbeit beschäftigt sich mit Konflikten bei der Abgrenzung von Fusionskontrollkompetenzen. Zudem wird ein Alternativmodell erarbeitet, das dem bestehenden System aus ökonomischer Perspektive überlegen ist.
Der Mensch in der Moderne lebt in einem Spannungsverhältnis zwischen all dem, was nun menschenmöglich erscheint und dem, was er als Einzelner, aufgrund seines beschränkten Kräftehaushalts, zu leisten vermag. Die notwendige Spezialisierung in einem beschränkten Feld schließt ihn, wie Max Weber es in »Wissenschaft als Beruf« darstellt, von vielen anderen Bereichen aus. Besonders eklatant wird dies in der Zeit der Wende vom 19. zum 20. Jahrhundert empfunden, welche die verschiedensten Versuche hervorbringt, Synthesen zwischen den ausdifferenzierten Wissensgebieten herzustellen. Einen besonderen Stellenwert hat hier das Wissen der Naturwissenschaftler, auf welche noch der materialistische und positivistische Optimismus des 19. Jahrhunderts wirkt.
An den Autobiographien des spanischen Histologen Santiago Ramón y Cajal (1852-1934) und des deutschen Chemikers Wilhelm Ostwald (1853-1932) zeigt sich exemplarisch, wie naturwissenschaftliche Spezialisten als Autoren auf dieses Spannungsverhältnis reagieren. In drei Kapiteln führt die literaturwissenschaftliche Untersuchung vor, wie die Autoren sprachliche Formen aus ihrer Spezialisierung entlehnen und für die Darstellung des eigenen Lebens nutzen. Historisch führt die Lektüre zu dem Schluss, dass in diesen Texten eine Verschiebung des Positivismus aus der Philosophie in die Autobiographik stattfindet.
Systematisch stellt der im Band entwickelte Begriff des biographischen Lebenswissens einen Versuch dar, das Leben des Einzelnen für die Sinngebung im Text starkzumachen, ohne in Biographismus oder ein Konzept starker Autorschaft zurückzufallen.
Exzentrik und Bürgertum
(2015)
Es wird eine verzweigte Intellektuellen- und Ideengeschichte um 1900 aufgeschlagen. Der Sozialphilosoph – heute aber vor allem als Schwiegersohn Wagners, Bayreuther Ideologe und Vordenker Hitlers bekannte – Chamberlain pflegte intensive Beziehungen zu jüdischen Intellektuellen. Erstaunliche Konstellationen zwischen Rassentheorie, Kulturreform, Kunst und Wissenschaft werden in einer Zeit lebendig, in der sich antisemitische und zionistische Anschauungen konsolidierten, revolutionär Konservative auf avantgardistische Künstler trafen und sich reformbewegte Sonnenanbeter gleichzeitig links- und rechtspopulistisch orientierten.
Kritische Untersuchungen zu Chamberlain und Persönlichkeiten jüdischer Herkunft sind ein Desiderat. Die Analyse und Auswertung dieser unbekannten Korrespondenzen und Hintergründe zielen in den Kernbereich deutsch-jüdischer Forschung. Das Buch zeigt Chamberlain, der in der kulturellen Szene Wiens und Bayreuths zwischen 1890 und 1920 eine Schlüsselfigur darstellt, im feingeistigen Austausch mit jüdischen Intellektuellen wie Karl Kraus, Walther Rathenau, Maximilian Harden, Otto Weininger und Martin Buber.
Es werden ideologische Verschränkungen in der Moderne und daraus resultierende Verhaltensmuster herausragender Persönlichkeiten aufgedeckt, die in Bezug auf antisemitische Verkrümmungen und sogenannten jüdischen Selbsthass eine lange Vorgeschichte des »Dritten Reiches« belegen.
Recent experiments show that transcription factors (TFs) indeed use the facilitated diffusion mechanism to locate their target sequences on DNA in living bacteria cells: TFs alternate between sliding motion along DNA and relocation events through the cytoplasm. From simulations and theoretical analysis we study the TF-sliding motion for a large section of the DNA-sequence of a common E. coli strain, based on the two-state TF-model with a fast-sliding search state and a recognition state enabling target detection. For the probability to detect the target before dissociating from DNA the TF-search times self-consistently depend heavily on whether or not an auxiliary operator (an accessible sequence similar to the main operator) is present in the genome section. Importantly, within our model the extent to which the interconversion rates between search and recognition states depend on the underlying nucleotide sequence is varied. A moderate dependence maximises the capability to distinguish between the main operator and similar sequences. Moreover, these auxiliary operators serve as starting points for DNA looping with the main operator, yielding a spectrum of target detection times spanning several orders of magnitude. Auxiliary operators are shown to act as funnels facilitating target detection by TFs.
The coordination of cell polarity within the plane of the tissue layer (planar polarity) is crucial for the development of diverse multicellular organisms. Small Rac/Rho-family GTPases and the actin cytoskeleton contribute to planar polarity formation at sites of polarity establishment in animals and plants. Yet, upstream pathways coordinating planar polarity differ strikingly between kingdoms. In the root of Arabidopsis thaliana, a concentration gradient of the phytohormone auxin coordinates polar recruitment of Rho-of-plant (ROP) to sites of polar epidermal hair initiation. However, little is known about cytoskeletal components and interactions that contribute to this planar polarity or about their relation to the patterning machinery. Here, we show that ACTIN7 (ACT7) represents a main actin isoform required for planar polarity of root hair positioning, interacting with the negative modulator ACTIN-INTERACTING PROTEIN1-2 (AIP1-2). ACT7, AIP1-2 and their genetic interaction are required for coordinated planar polarity of ROP downstream of ethylene signalling. Strikingly, AIP1-2 displays hair cell file-enriched expression, restricted by WEREWOLF (WER)-dependent patterning and modified by ethylene and auxin action. Hence, our findings reveal AIP1-2, expressed under control of the WER-dependent patterning machinery and the ethylene signalling pathway, as a modulator of actin-mediated planar polarity.
Patterned differentiation of distinct cell types is essential for the development of multicellular organisms. The root epidermis of Arabidopsis thaliana is composed of alternating files of root hair and non-hair cells and represents a model system for studying the control of cell-fate acquisition. Epidermal cell fate is regulated by a network of genes that translate positional information from the underlying cortical cell layer into a specific pattern of differentiated cells. While much is known about the genes of this network, new players continue to be discovered. Here we show that the SABRE (SAB) gene, known to mediate microtubule organization, anisotropic cell growth and planar polarity, has an effect on root epidermal hair cell patterning. Loss of SAB function results in ectopic root hair formation and destabilizes the expression of cell fate and differentiation markers in the root epidermis, including expression of the WEREWOLF (WER) and GLABRA2 (GL2) genes. Double mutant analysis reveal that wer and caprice (cpc) mutants, defective in core components of the epidermal patterning pathway, genetically interact with sab. This suggests that SAB may act on epidermal patterning upstream of WER and CPC. Hence, we provide evidence for a role of SAB in root epidermal patterning by affecting cell-fate stabilization. Our work opens the door for future studies addressing SAB-dependent functions of the cytoskeleton during root epidermal patterning.
Der Nötigungsnotstand
(2015)
Foreign Accent Syndrome
(2015)
Forcing Earth’s sea level
(2015)