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Fruits exhibit a vast array of different 3D shapes, from simple spheres and cylinders to more complex curved forms; however, the mechanism by which growth is oriented and coordinated to generate this diversity of forms is unclear. Here, we compare the growth patterns and orientations for two very different fruit shapes in the Brassicaceae: the heart-shaped Capsella rubella silicle and the near-cylindrical Arabidopsis thaliana silique. We show, through a combination of clonal and morphological analyses, that the different shapes involve different patterns of anisotropic growth during three phases. These experimental data can be accounted for by a tissue level model in which specified growth rates vary in space and time and are oriented by a proximodistal polarity field. The resulting tissue conflicts lead to deformation of the tissue as it grows. The model allows us to identify tissue-specific and temporally specific activities required to obtain the individual shapes. One such activity may be provided by the valve-identity gene FRUITFULL, which we show through comparative mutant analysis to modulate fruit shape during post-fertilisation growth of both species. Simple modulations of the model presented here can also broadly account for the variety of shapes in other Brassicaceae species, thus providing a simplified framework for fruit development and shape diversity.
Since the 1960ies, Germany has been host to a large Turkish immigrant community. While migrant communities often shift to the majority language over the course of time, Turkish is a very vital minority language in Germany and bilingualism in this community is an obvious fact which has been subject to several studies. The main focus usually is on German, the second language (L2) of these speakers (e.g. Hinnenkamp 2000, Keim 2001, Auer 2003, Cindark & Aslan (2004), Kern & Selting 2006, Selting 2009, Kern 2013). Research on the Turkish spoken by Turkish bilinguals has also attracted attention although to a lesser extend mainly in the framework of so called heritage language research (cf. Polinski 2011). Bilingual Turkish has been investigated under the perspective of code-switching and codemixing (e.g. Kallmeyer & Keim 2003, Keim 2003, 2004, Keim & Cindark 2003, Hinnenkamp 2003, 2005, 2008, Dirim & Auer 2004), and with respect to changes in the morphologic, the syntactic and the orthographic system (e.g. Rehbein & Karakoç 2004, Schroeder 2007). Attention to the changes in the prosodic system of bilingual Turkish on the other side has been exceptional so far (Queen 2001, 2006).
With the present dissertation, I provide a study on contact induced linguistic changes on the prosodic level in the Turkish heritage language of adult early German-Turkish bilinguals. It describes structural changes in the L1 Turkish intonation of yes/no questions of a representative sample of bilingual Turkish speakers. All speakers share a similar sociolinguistic background. All acquired Turkish as their first language from their families and the majority language German as an early L2 at latest in the kinder garden by the age of 3.
A study of changes in bilingual varieties requires a previous cross-linguistic comparison of both of the involved languages in language contact in order to draw conclusions on the contact-induced language change in delimitation to language-internal development.
While German is one of the best investigated languages with respect to its prosodic system, research on Turkish intonational phonology is not as progressed. To this effect, the analysis of bilingual Turkish, as elicited for the present dissertation, is preceded by an experimental study on monolingual Turkish. In this regard an additional experiment with 11 monolingual university students of non-linguistic subjects was conducted at the Ege University in Izmir in 2013. On these grounds the present dissertation additionally contributes new insights with respect to Turkish intonational phonology and typology. The results of the contrastive analysis of German and Turkish bring to light that the prosodic systems of both languages differ with respect to the use of prosodic cues in the marking of information structure (IS) and sentence type. Whereas German distinguishes in the prosodic marking between explicit categories for focus and givenness, Turkish uses only one prosodic cue to mark IS. Furthermore it is shown that Turkish in contrast to German does not use a prosodic correlate to mark yes/no questions, but a morphological question marker.
To elicit Turkish yes/no questions in a bilingual context which differ with respect to their information structure in a further step the methodology of Xu (1999) to elicit in-situ focus on different constituents was adapted in the experimental study. A data set of 400 Turkish yes/no questions of 20 bilingual Turkish speakers was compiled at the Zentrum für Allgemeine Sprachwissenschaft (ZAS) in Berlin and at the University of Potsdam in 2013. The prosodic structure of the yes/no questions was phonologically and phonetically analyzed with respect to changes in the f0 contour according to IS modifications and the use of prosodic cues to indicate sentence type.
The results of the analyses contribute surprising observations to the research of bilingual prosody. Studies on bilingual language change and language acquisition have repeatedly shown that the use of prosodic features that are considered as marked by means of lower and implicational use across and within a language cause difficulties in language contact and second language acquisition. Especially, they are not expected to pass from one language to another through language contact. However, this structurally determined expectation on language development is refuted by the results of the present study. Functionally related prosody, such as the cues to indicate IS, are transferred from German L2 to the Turkish L1 of German-Turkish bilingual speakers. This astonishing observation provides the base for an approach to language change centered on functional motivation. Based on Matras’ (2007, 2010) assumption of functionality in language change, Paradis’ (1993, 2004, 2008) approach of Language Activation and the Subsystem Theory and the Theory of Language as a Dynamic System (Heredina & Jessner 2002), it will be shown that prosodic features which are absent in one of the languages of bilingual speech communities are transferred from the respective language to the other when they contribute to the contextualization of a pragmatic concept which is not expressed by other linguistic means in the target language. To this effect language interaction is based on language activation and inhibition mechanisms dealing with differences in the implicit pragmatic knowledge between bilinguals and monolinguals. The motivator for this process of language change is the contextualization of the message itself and not the structure of the respective feature on the surface. It is shown that structural consideration may influence language change but that bilingual language change does not depend on structural restrictions nor does the structure cause a change. The conclusions drawn on the basis of empirical facts can especially contribute to a better understanding of the processes of bilingual language development as it combines methodologies and theoretical aspects of different linguistic subfields.
Die vorliegende Arbeit befasst sich mit Führungsverhalten im öffentlichen Sektor sowie mit Einflussfaktoren auf dieses Führungsverhalten. Hierzu wurde eine Taxonomie, bestehend aus sechs Metakategorien von Führungsverhalten, entwickelt. Die Metakategorien umfassen Aufgaben-, Beziehungs-, Veränderungs-, Außen-, Ethik- und Sachbearbeitungsorientierung. Eine Analyse von Umfragedaten, die für diese Arbeit bei Mitarbeitern und unteren Führungskräften dreier Behörden erhoben wurden, zeigt, dass diese Taxonomie sehr gut geeignet ist, die Führungsrealität in der öffentlichen Verwaltung abzubilden.
Eine deskriptive Auswertung der Daten zeigt außerdem, dass es eine relativ große Differenz zwischen der Selbsteinschätzung der Führungskräfte und der Fremdeinschätzung durch ihre Mitarbeiter gibt. Diese Differenz ist bei der Beziehungs- und Veränderungsorientierung besonders hoch.
Der deskriptiven Auswertung schließt sich eine Analyse von Einflussfaktoren auf das Führungsverhalten an. Die Einflussfaktoren können den vier Kategorien "Charakteristika und Eigenschaften der Führungskräfte", "Erwartungen und Interesse von Vorgesetzten", "Charakteristika und Einstellungen von Geführten" und "Managementinstrumente und -rahmenbedingungen" zugeordnet werden.
Eine Analyse mit Hilfe von hierarchischen linearen Modellen zeigt, dass vor allem die Führungsmotivation und die Managementorientierung der Führungskräfte, die Gemeinwohlorientierung und die Art der Aufgabe der Geführten sowie die strategische Führungskräfteauswahl und die Leistungsmessung durch die Führungskräfte anhand konkreter Ziele einen Einfluss auf das Führungsverhalten haben.
Die Ergebnisse dieser Arbeit ergänzen die Literatur zu Führungsverhalten im öffentlichen Sektor um die Perspektive der Einflussfaktoren auf das Führungsverhalten und leisten zusätzlich mit Hilfe der verwendeten Taxonomie einen Beitrag zur theoretischen Diskussion von Führungsverhalten in der Public-Management-Forschung. Darüber hinaus bieten die gewonnenen Erkenntnisse der Verwaltungspraxis Hinweise zu relevanten Einflussfaktoren auf das Führungsverhalten sowie auf beachtliche Differenzen zwischen Selbst- und Fremdwahrnehmung des Führungsverhaltens.
Lake Towuti is a tectonic basin, surrounded by ultramafic rocks. Lateritic soils form through weathering and deliver abundant iron (oxy)hydroxides but very little sulfate to the lake and its sediment. To characterize the sediment biogeochemistry, we collected cores at three sites with increasing water depth and decreasing bottom water oxygen concentrations. Microbial cell densities were highest at the shallow site a feature we attribute to the availability of labile organic matter (OM) and the higher abundance of electron acceptors due to oxic bottom water conditions. At the two other sites, OM degradation and reduction processes below the oxycline led to partial electron acceptor depletion. Genetic information preserved in the sediment as extracellular DNA (eDNA) provided information on aerobic and anaerobic heterotrophs related to Nitrospirae. Chloroflexi, and Therrnoplasmatales. These taxa apparently played a significant role in the degradation of sinking OM. However, eDNA concentrations rapidly decreased with core depth. Despite very low sulfate concentrations, sulfate-reducing bacteria were present and viable in sediments at all three sites, as confirmed by measurement of potential sulfate reduction rates. Microbial community fingerprinting supported the presence of taxa related to Deltaproteobacteria and Firmicutes with demonstrated capacity for iron and sulfate reduction. Concomitantly, sequences of Ruminococcaceae, Clostridiales, and Methanornicrobiales indicated potential for fermentative hydrogen and methane production. Such first insights into ferruginous sediments showed that microbial populations perform successive metabolisms related to sulfur, iron, and methane. In theory, iron reduction could reoxidize reduced sulfur compounds and desorb OM from iron minerals to allow remineralization to methane. Overall, we found that biogeochemical processes in the sediments can be linked to redox differences in the bottom waters of the three sites, like oxidant concentrations and the supply of labile OM. At the scale of the lacustrine record, our geomicrobiological study should provide a means to link the extant subsurface biosphere to past environments.
We analyzed the population genetic pattern of 12 fragmented Geropogon hybridus ecological range edge populations in Israel along a steep precipitation gradient. In the investigation area (45 x 20 km(2)), the annual mean precipitation changes rapidly from 450 mm in the north (Mediterranean-influenced climate zone) to 300 mm in the south (semiarid climate zone) without significant temperature changes. Our analysis (91 individuals, 12 populations, 123 polymorphic loci) revealed strongly structured populations (AMOVA I broken vertical bar(ST) = 0.35; P < 0.001); however, differentiation did not change gradually toward range edge. IBD was significant (Mantel test r = 0.81; P = 0.001) and derived from sharply divided groups between the northernmost populations and the others further south, due to dispersal or environmental limitations. This was corroborated by the PCA and STRUCTURE analyses. IBD and IBE were significant despite the micro-geographic scale of the study area, which indicates that reduced precipitation toward range edge leads to population genetic divergence. However, this pattern diminished when the hypothesized gene flow barrier was taken into account. Applying the spatial analysis method revealed 11 outlier loci that were correlated to annual precipitation and, moreover, were indicative for putative precipitation-related adaptation (BAYESCAN, MCHEZA). The results suggest that even on micro-geographic scales, environmental factors play prominent roles in population divergence, genetic drift, and directional selection. The pattern is typical for strong environmental gradients, e.g., at species range edges and ecological limits, and if gene flow barriers and mosaic-like structures of fragmented habitats hamper dispersal.
Glocke und Ikone
(2016)
The gravitational field of a laser pulse of finite lifetime, is investigated in the framework of linearized gravity. Although the effects are very small, they may be of fundamental physical interest. It is shown that the gravitational field of a linearly polarized light pulse is modulated as the norm of the corresponding electric field strength, while no modulations arise for circular polarization. In general, the gravitational field is independent of the polarization direction. It is shown that all physical effects are confined to spherical shells expanding with the speed of light, and that these shells are imprints of the spacetime events representing emission and absorption of the pulse. Nearby test particles at rest are attracted towards the pulse trajectory by the gravitational field due to the emission of the pulse, and they are repelled from the pulse trajectory by the gravitational field due to its absorption. Examples are given for the size of the attractive effect. It is recovered that massless test particles do not experience any physical effect if they are co-propagating with the pulse, and that the acceleration of massless test particles counter-propagating with respect to the pulse is four times stronger than for massive particles at rest. The similarities between the gravitational effect of a laser pulse and Newtonian gravity in two dimensions are pointed out. The spacetime curvature close to the pulse is compared to that induced by gravitational waves from astronomical sources.
Grenzräume – Grenzbewegungen
(2016)
Der vorliegende Sammelband vereinigt die Beiträge der 12. und 13. Tagung des Jungen Forums Slavistische Literaturwissenschaft (JFSL) in Basel 2013 und Frankfurt (Oder) und Słubice 2014. Unter den thematischen Leitbegriffen Grenzräume – Grenzbewegungen präsentiert er Einblicke in die Arbeit von Nachwuchswissenschaftlerinnen und -wissenschaftlern der deutschsprachigen slavischen Literatur- und Kulturwissenschaft.
Grenzräume – Grenzbewegungen
(2016)
Der vorliegende Sammelband vereinigt die Beiträge der 12. und 13. Tagung des Jungen Forums Slavistische Literaturwissenschaft (JFSL) in Basel 2013 und Frankfurt (Oder) und Słubice 2014. Unter den thematischen Leitbegriffen Grenzräume – Grenzbewegungen präsentiert er Einblicke in die Arbeit von Nachwuchswissenschaftlerinnen und -wissenschaftlern der deutschsprachigen slavischen Literatur- und Kulturwissenschaft.
We do magnetohydrodynamic (MHD) simulations of local box models of turbulent Interstellar Medium (ISM) and analyse the process of amplification and saturation of mean magnetic fields with methods of mean field dynamo theory. It is shown that the process of saturation of mean fields can be partially described by the prolonged diffusion time scales in presence of the dynamically significant magnetic fields. However, the outward wind also plays an essential role in the saturation in higher SN rate case. Algebraic expressions for the back reaction of the magnetic field onto the turbulent transport coefficients are derived, which allow a complete description of the nonlinear dynamo. We also present the effects of dynamically significant mean fields on the ISM configuration and pressure distribution. We further add the cosmic ray component in the simulations and investigate the kinematic growth of mean fields with a dynamo perspective.
Gute Brücke
(2016)
Herzenswärme
(2016)
Background:
First metabolomics studies have indicated that metabolic fingerprints from accessible tissues might
be useful to better understand the etiological links between metabolism and cancer. However, there is still a lack
of prospective metabolomics studies on pre-diagnostic metabolic alterations and cancer risk.
Methods:
Associations between pre-diagnostic levels of 120 circulating metabolites (acylcarnitines, amino acids,
biogenic amines, phosphatidylcholines, sphingolipids, and hexoses) and the risks of breast, prostate, and colorectal
cancer were evaluated by Cox regression analyses using data of a prospective case-cohort study including 835
incident cancer cases.
Results:
The median follow-up duration was 8.3 years among non-cases and 6.5 years among incident cases of
cancer. Higher levels of lysophosphatidylcholines (lysoPCs), and especially lysoPC a C18:0, were consistently related
to lower risks of breast, prostate, and colorectal cancer, independent of background factors. In contrast, higher
levels of phosphatidylcholine PC ae C30:0 were associated with increased cancer risk. There was no heterogeneity
in the observed associations by lag time between blood draw and cancer diagnosis.
Conclusion:
Changes in blood lipid composition precede the diagnosis of common malignancies by several years.
Considering the consistency of the present results across three cancer types the observed alterations point to a
global metabolic shift in phosphatidylcholine metabolism that may drive tumorigenesis.
Ingo Schwarz: Opfer für die Wissenschaften „in dem Drange wichtiger öffentlicher Begebenheiten“ Briefe von Alexander von Humboldt an Friedrich Wilhelm III., 1806
Reinhard Andress: Eine Bitte an Thomas Jefferson um Tabaksamen und Tabak: ein unveröffentlichter Brief Alexander von Humboldts
Ottmar Ette: Naturaleza y cultura: perspectivas científico-vitales de la ciencia de Humboldt
Miguel Ángel Puig-Samper, Elisa Garrido: The presentation of the results of Alexander von Humboldt's voyage to Carlos IV
Thomas Schmuck: Humboldt in Goethes Bibliothek
Bärbel Rott: Alexander von Humboldt brachte Guano nach Europa - mit ungeahnten globalen Folgen
Inhalt
- Reinhard Andress: Ein unveröffentlichter Brief Alexander von Humboldts an den Buchhändler Jean-Georges Treuttel
- Julian Drews: Écriture (auto)biographique dans l‘Examen critique d‘Alexandre de Humboldt
- Alberto Gómez Gutiérrez: Alexander von Humboldt y la cooperación transcontinental en la Geografía de las plantas: una nueva apreciación de la obra fitogeográfica de Francisco José de Caldas
- Karin Reich und Elena Roussanova: Der Briefwechsel zwischen Karl Kreil und Alexander von Humboldt, ein wichtiger Beitrag zur Geschichte des Erdmagnetismus
- Alexander Stöger: Experiment und Wissensvermittlung. Alexander von Humboldts Darstellungsmethoden in seinen Versuchen über die gereizte Muskel- und Nervenfaser
- Friedrich Herneck und Ingo Schwarz: Friedrich Herneck: Hegel und Alexander von Humboldt
Die 7. Fachtagung für Hochschuldidaktik, die 2016 erneut mit der DeLFI E-Learning Fachtagung Informatik stattfand, setzte das erfolgreiche Modell einer Tagung fort, die sich mit hochschuldidaktischen Fragen und der Gestaltung von Studiengängen der Informatik beschäftigt.
Thema der Tagung waren alle Fragen, die sich der Vermittlung von Informatikgegenständen im Hochschulbereich widmen. Dazu gehörten u.a.:
• fachdidaktische Konzepte der Vermittlung einzelner Informatikgegenstände
• methodische Lösungen, wie spezielle Lehr- und Lernformen, Durchführungskonzepte
• empirische Ergebnisse und Vergleichsstudien
• E-Learning-Ansätze, wenn sie ein erkennbares didaktisches Konzept verfolgen
• Studienkonzepte und Curricula, organisatorische Fragen, wie Gewinnung von Studierenden, Studieneingangsphase, Abbrecher.
Die Fachtagung widmete sich ausgewählten Fragestellungen dieses Themenkomplexes, die durch Vorträge ausgewiesener Experten, durch eingereichte Beiträge und durch Präsentationen und Poster intensiv behandelt wurden.
Unser besonderer Dank gilt dem Programmkomitee und den hier nicht genannten Helfern für ihren Einsatz bei der Vorbereitung und Durchführung der Tagung.
Understanding the role of natural climate variability under the pressure of human induced changes of climate and landscapes, is crucial to improve future projections and adaption strategies. This doctoral thesis aims to reconstruct Holocene climate and environmental changes in NE Germany based on annually laminated lake sediments. The work contributes to the ICLEA project (Integrated CLimate and Landscape Evolution Analyses). ICLEA intends to compare multiple high-resolution proxy records with independent chronologies from the N central European lowlands, in order to disentangle the impact of climate change and human land use on landscape development during the Lateglacial and Holocene. In this respect, two study sites in NE Germany are investigated in this doctoral project, Lake Tiefer See and palaeolake Wukenfurche. While both sediment records are studied with a combination of high-resolution sediment microfacies and geochemical analyses (e.g. µ-XRF, carbon geochemistry and stable isotopes), detailed proxy understanding mainly focused on the continuous 7.7 m long sediment core from Lake Tiefer See covering the last ~6000 years. Three main objectives are pursued at Lake Tiefer See: (1) to perform a reliable and independent chronology, (2) to establish microfacies and geochemical proxies as indicators for climate and environmental changes, and (3) to trace the effects of climate variability and human activity on sediment deposition.
Addressing the first aim, a reliable chronology of Lake Tiefer See is compiled by using a multiple-dating concept. Varve counting and tephra findings form the chronological framework for the last ~6000 years. The good agreement with independent radiocarbon dates of terrestrial plant remains verifies the robustness of the age model. The resulting reliable and independent chronology of Lake Tiefer See and, additionally, the identification of nine tephras provide a valuable base for detailed comparison and synchronization of the Lake Tiefer See data set with other climate records. The sediment profile of Lake Tiefer See exhibits striking alternations between well-varved and non-varved sediment intervals. The combination of microfacies, geochemical and microfossil (i.e. Cladocera and diatom) analyses indicates that these changes of varve preservation are caused by variations of lake circulation in Lake Tiefer See. An exception is the well-varved sediment deposited since AD 1924, which is mainly influenced by human-induced lake eutrophication. Well-varved intervals before the 20th century are considered to reflect phases of reduced lake circulation and, consequently, stronger anoxic conditions. Instead, non-varved intervals indicate increased lake circulation in Lake Tiefer See, leading to more oxygenated conditions at the lake ground. Furthermore, lake circulation is not only influencing sediment deposition, but also geochemical processes in the lake. As, for example, the proxy meaning of δ13COM varies in time in response to changes of the oxygen regime in the lake hypolinion. During reduced lake circulation and stronger anoxic conditions δ13COM is influenced by microbial carbon cycling. In contrast, organic matter degradation controls δ13COM during phases of intensified lake circulation and more oxygenated conditions. The varve preservation indicates an increasing trend of lake circulation at Lake Tiefer See after ~4000 cal a BP. This trend is superimposed by decadal to centennial scale variability of lake circulation intensity. Comparison to other records in Central Europe suggests that the long-term trend is probably related to gradual changes in Northern Hemisphere orbital forcing, which induced colder and windier conditions in Central Europe and, therefore, reinforced lake circulation. Decadal to centennial scale periods of increased lake circulation coincide with settlement phases at Lake Tiefer See, as inferred from pollen data of the same sediment record. Deforestation reduced the wind shelter of the lake, which probably increased the sensitivity of lake circulation to wind stress. However, results of this thesis also suggest that several of these phases of increased lake circulation are additionally reinforced by climate changes. A first indication is provided by the comparison to the Baltic Sea record, which shows striking correspondence between major non-varved intervals at Lake Tiefer See and bioturbated sediments in the Baltic Sea. Furthermore, a preliminary comparison to the ICLEA study site Lake Czechowskie (N central Poland) shows a coincidence of at least three phases of increased lake circulation in both lakes, which concur with periods of known climate changes (2.8 ka event, ’Migration Period’ and ’Little Ice Age’). These results suggest an additional over-regional climate forcing also on short term increased of lake circulation in Lake Tiefer See.
In summary, the results of this thesis suggest that lake circulation at Lake Tiefer See is driven by a combination of long-term and short-term climate changes as well as of anthropogenic deforestation phases. Furthermore, the lake circulation drives geochemical cycles in the lake affecting the meaning of proxy data. Therefore, the work presented here expands the knowledge of climate and environmental variability in NE Germany. Furthermore, the integration of the Lake Tiefer See multi-proxy record in a regional comparison with another ICLEA side, Lake Czechowskie, enabled to better decipher climate changes and human impact on the lake system. These first results suggest a huge potential for further detailed regional comparisons to better understand palaeoclimate dynamics in N central Europe.
The extent of gene flow during the range expansion of non-native species influences the amount of genetic diversity retained in expanding populations. Here, we analyse the population genetic structure of the raccoon dog (Nyctereutes procyonoides) in north-eastern and central Europe. This invasive species is of management concern because it is highly susceptible to fox rabies and an important secondary host of the virus. We hypothesized that the large number of introduced animals and the species' dispersal capabilities led to high population connectivity and maintenance of genetic diversity throughout the invaded range. We genotyped 332 tissue samples from seven European countries using 16 microsatellite loci. Different algorithms identified three genetic clusters corresponding to Finland, Denmark and a large 'central' population that reached from introduction areas in western Russia to northern Germany. Cluster assignments provided evidence of long-distance dispersal. The results of an Approximate Bayesian Computation analysis supported a scenario of equal effective population sizes among different pre-defined populations in the large central cluster. Our results are in line with strong gene flow and secondary admixture between neighbouring demes leading to reduced genetic structuring, probably a result of its fairly rapid population expansion after introduction. The results presented here are remarkable in the sense that we identified a homogenous genetic cluster inhabiting an area stretching over more than 1500km. They are also relevant for disease management, as in the event of a significant rabies outbreak, there is a great risk of a rapid virus spread among raccoon dog populations.
The aim of the present study was to test the functional relevance of the spatial concepts UP or DOWN for words that use these concepts either literally (space) or metaphorically (time, valence). A functional relevance would imply a symmetrical relationship between the spatial concepts and words related to these concepts, showing that processing words activate the related spatial concepts on one hand, but also that an activation of the concepts will ease the retrieval of a related word on the other. For the latter, the rotation angle of participant's body position was manipulated either to an upright or a head-down tilted body position to activate the related spatial concept. Afterwards participants produced in a within-subject design previously memorized words of the concepts space, time and valence according to the pace of a metronome. All words were related either to the spatial concept UP or DOWN. The results including Bayesian analyses show (1) a significant interaction between body position and words using the concepts UP and DOWN literally, (2) a marginal significant interaction between body position and temporal words and (3) no effect between body position and valence words. However, post-hoc analyses suggest no difference between experiments. Thus, the authors concluded that integrating sensorimotor experiences is indeed of functional relevance for all three concepts of space, time and valence. However, the strength of this functional relevance depends on how close words are linked to mental concepts representing vertical space.
Processes involved in late bilinguals' production of morphologically complex words were studied using an event-related brain potentials (ERP) paradigm in which EEGs were recorded during participants' silent productions of English past- and present-tense forms. Twenty-three advanced second language speakers of English (first language [L1] German) were compared to a control group of 19 L1 English speakers from an earlier study. We found a frontocentral negativity for regular relative to irregular past-tense forms (e.g., asked vs. held) during (silent) production, and no difference for the present-tense condition (e.g., asks vs. holds), replicating the ERP effect obtained for the L1 group. This ERP effect suggests that combinatorial processing is involved in producing regular past-tense forms, in both late bilinguals and L1 speakers. We also suggest that this paradigm is a useful tool for future studies of online language production.
Processes involved in late bilinguals' production of morphologically complex words were studied using an event-related brain potentials (ERP) paradigm in which EEGs were recorded during participants' silent productions of English past- and present-tense forms. Twenty-three advanced second language speakers of English (first language [L1] German) were compared to a control group of 19 L1 English speakers from an earlier study. We found a frontocentral negativity for regular relative to irregular past-tense forms (e.g., asked vs. held) during (silent) production, and no difference for the present-tense condition (e.g., asks vs. holds), replicating the ERP effect obtained for the L1 group. This ERP effect suggests that combinatorial processing is involved in producing regular past-tense forms, in both late bilinguals and L1 speakers. We also suggest that this paradigm is a useful tool for future studies of online language production.
In this paper, we show experimentally that inside a microfluidic device, where the reactants are segregated, the reaction rate of an autocatalytic clock reaction is accelerated in comparison to the case where all the reactants are well mixed. We also find that, when mixing is enhanced inside the microfluidic device by introducing obstacles into the flow, the clock reaction becomes slower in comparison to the device where mixing is less efficient. Based on numerical simulations, we show that this effect can be explained by the interplay of nonlinear reaction kinetics (cubic autocatalysis) and differential diffusion, where the autocatalytic species diffuses slower than the substrate.
The current study investigates to what extent masked morphological priming is modulated by language-particular properties, specifically by its writing system. We present results from two masked priming experiments investigating the processing of complex Japanese words written in less common (moraic) scripts. In Experiment 1, participants performed lexical decisions on target verbs; these were preceded by primes which were either (i) a past-tense form of the same verb, (ii) a stem-related form with the epenthetic vowel -i, (iii) a semantically-related form, and (iv) a phonologically-related form. Significant priming effects were obtained for prime types (i), (ii), and (iii), but not for (iv). This pattern of results differs from previous findings on languages with alphabetic scripts, which found reliable masked priming effects for morphologically related prime/target pairs of type (i), but not for non-affixal and semantically-related primes of types (ii), and (iii). In Experiment 2, we measured priming effects for prime/target pairs which are neither morphologically, semantically, phonologically nor - as presented in their moraic scripts—orthographically related, but which—in their commonly written form—share the same kanji, which are logograms adopted from Chinese. The results showed a significant priming effect, with faster lexical-decision times for kanji-related prime/target pairs relative to unrelated ones. We conclude that affix-stripping is insufficient to account for masked morphological priming effects across languages, but that language-particular properties (in the case of Japanese, the writing system) affect the processing of (morphologically) complex words.
In this contribution, we study using first principles the co-adsorption and catalytic behaviors of CO and O2 on a single gold atom deposited at defective magnesium oxide surfaces. Using cluster models and point charge embedding within a density functional theory framework, we simulate the CO oxidation reaction for Au1 on differently charged oxygen vacancies of MgO(001) to rationalize its experimentally observed lack of catalytic activity. Our results show that: (1) co-adsorption is weakly supported at F0 and F2+ defects but not at F1+ sites, (2) electron redistribution from the F0 vacancy via the Au1 cluster to the adsorbed molecular oxygen weakens the O2 bond, as required for a sustainable catalytic cycle, (3) a metastable carbonate intermediate can form on defects of the F0 type, (4) only a small activation barrier exists for the highly favorable dissociation of CO2 from F0, and (5) the moderate adsorption energy of the gold atom on the F0 defect cannot prevent insertion of molecular oxygen inside the defect. Due to the lack of protection of the color centers, the surface becomes invariably repaired by the surrounding oxygen and the catalytic cycle is irreversibly broken in the first oxidation step.
Skipping a grade, one specific form of acceleration, is an intervention used for gifted students. Quantitative research has shown acceleration to be a highly successful intervention regarding academic achievement, but less is known about the social-emotional outcomes of grade-skipping. In the present study, the authors used the grounded theory approach to examine the experiences of seven gifted students aged 8 to 16 years who skipped a grade. The interviewees perceived their feeling of being in the wrong place before the grade-skipping as strongly influenced by their teachers, who generally did not respond adequately to their needs. We observed a close interrelationship between the gifted students' intellectual fit and their social situation in class. Findings showed that the grade-skipping in most of the cases bettered the situation in school intellectually as well as socially, but soon further interventions, for instance, a specialized and demanding class- or subject-specific acceleration were added to provide sufficiently challenging learning opportunities.
HPI Future SOC Lab
(2016)
The “HPI Future SOC Lab” is a cooperation of the Hasso Plattner Institute (HPI) and industrial partners. Its mission is to enable and promote exchange and interaction between the research community and the industrial partners.
The HPI Future SOC Lab provides researchers with free of charge access to a complete infrastructure of state of the art hard and software. This infrastructure includes components, which might be too expensive for an ordinary research environment, such as servers with up to 64 cores and 2 TB main memory. The offerings address researchers particularly from but not limited to the areas of computer science and business information systems. Main areas of research include cloud computing, parallelization, and In-Memory technologies.
This technical report presents results of research projects executed in 2016. Selected projects have presented their results on April 5th and November 3th 2016 at the Future SOC Lab Day events.
In Goethes privater Bibliothek im Goethehaus in Weimar ist Alexander von Humboldt mehrfach vertreten: durch persönlich übersandte Bücher, durch Broschüren und Grafiken. Einige dieser Publikationen Humboldts tragen handschriftliche Widmungen. Die Anmerkungen Goethes, seine Bearbeitungsspuren, die Bemerkungen im Tagebuch und nicht zuletzt der Briefwechsel geben Aufschluss über eine komplizierte Beziehung, die von Wohlwollen und von wissenschaftlichem Interesse an der Arbeit des anderen geprägt war, im Alter aber, insbesondere bei Humboldt, spürbar distanzierter wurde. Erstmals werden in diesem Beitrag alle handschriftlichen Widmungen Humboldts an Goethe abgebildet und die Publikationen Humboldts in Goethes Bibliothek in einen wissenschaftshistorischen und lebensgeschichtlichen Kontext gestellt.
The goal of the presented work is to explore the interaction between gold nanorods (GNRs) and hyper-sound waves. For the generation of the hyper-sound I have used Azobenzene-containing polymer transducers. Multilayer polymer structures with well-defined thicknesses and smooth interfaces were built via layer-by-layer deposition. Anionic polyelectrolytes with Azobenzene side groups (PAzo) were alternated with cationic polymer PAH, for the creation of transducer films. PSS/PAH multilayer were built for spacer layers, which do not absorb in the visible light range. The properties of the PAzo/PAH film as a transducer are carefully characterized by static and transient optical spectroscopy. The optical and mechanical properties of the transducer are studied on the picosecond time scale. In particular the relative change of the refractive index of the photo-excited and expanded PAH/PAzo is Δn/n = - 2.6*10‐4. Calibration of the generated strain is performed by ultrafast X-ray diffraction calibrated the strain in a Mica substrate, into which the hyper-sound is transduced. By simulating the X-ray data with a linear-chain-model the strain in the transducer under the excitation is derived to be Δd/d ~ 5*10‐4.
Additional to the investigation of the properties of the transducer itself, I have performed a series of experiments to study the penetration of the generated strain into various adjacent materials. By depositing the PAzo/PAH film onto a PAH/PSS structure with gold nanorods incorporated in it, I have shown that nanoscale impurities can be detected via the scattering of hyper-sound.
Prior to the investigation of complex structures containing GNRs and the transducer, I have performed several sets of experiments on GNRs deposited on a small buffer of PSS/PAH. The static and transient response of GNRs is investigated for different fluence of the pump beam and for different dielectric environments (GNRs covered by PSS/PAH).
A systematic analysis of sample architectures is performed in order to construct a sample with the desired effect of GNRs responding to the hyper-sound strain wave. The observed shift of a feature related to the longitudinal plasmon resonance in the transient reflection spectra is interpreted as the event of GNRs sensing the strain wave. We argue that the shift of the longitudinal plasmon resonance is caused by the viscoelastic deformation of the polymer around the nanoparticle. The deformation is induced by the out of plane difference in strain in the area directly under a particle and next to it. Simulations based on the linear chain model support this assumption. Experimentally this assumption is proven by investigating the same structure, with GNRs embedded in a PSS/PAH polymer layer.
The response of GNRs to the hyper-sound wave is also observed for the sample structure with GNRs embedded in PAzo/PAH films. The response of GNRs in this case is explained to be driven by the change of the refractive index of PAzo during the strain propagation.
The lakes in the Kenyan Rift Valley offer the unique opportunity to study a wide range of hydrochemical environmental conditions, ranging from freshwater to highly saline and alkaline lakes. Because little is known about the hydro- and biogeochemical conditions in the underlying lake sediments, it was the aim of this study to extend the already existing data sets with data from porewater and biomarker analyses. Additionally, reduced sulphur compounds and sulphate reduction rates in the sediment were determined. The new data was used to examine the anthropogenic and microbial influence on the lakes sediments as well as the influence of the water chemistry on the degradation and preservation of organic matter in the sediment column. The lakes discussed in this study are: Logipi, Eight (a small crater lake in the region of Kangirinyang), Baringo, Bogoria, Naivasha, Oloiden, and Sonachi.
The biomarker compositions were similar in all studied lake sediments; nevertheless, there were some differences between the saline and freshwater lakes. One of those differences is the occurrence of a molecule related to β-carotene, which was only found in the saline lakes. This molecule most likely originates from cyanobacteria, single-celled organisms which are commonly found in saline lakes. In the two freshwater lakes, stigmasterol, a sterol characteristic for freshwater algae, was found. In this study, it was shown that Lakes Bogoria and Sonachi can be used for environmental reconstructions with biomarkers, because the absence of oxygen at the lake bottoms slowed the degradation process. Other lakes, like for example Lake Naivasha, cannot be used for such reconstructions, because of the large anthropogenic influence. But the biomarkers proved to be a useful tool to study those anthropogenic influences. Additionally, it was observed that horizons with a high concentration of elemental sulphur can be used as temporal markers. Those horizons were deposited during times when the lake levels were very low. The sulphur was deposited by microorganisms which are capable of anoxygenic photosynthesis or sulphide oxidation.
The new sediment record from the deep Dead Sea basin (ICDP core 5017-1) provides a unique archive for hydroclimatic variability in the Levant. Here, we present high-resolution sediment facies analysis and elemental composition by micro-X-ray fluorescence (mu XRF) scanning of core 5017-1 to trace lake levels and responses of the regional hydroclimatology during the time interval from ca. 117 to 75 ka, i. e. the transition between the last interglacial and the onset of the last glaciation. We distinguished six major micro-facies types and interpreted these and their alterations in the core in terms of relative lake level changes. The two end-member facies for highest and lowest lake levels are (a) up to several metres thick, greenish sediments of alternating aragonite and detrital marl laminae (aad) and (b) thick halite facies, respectively. Intermediate lake levels are characterised by detrital marls with varying amounts of aragonite, gypsum or halite, reflecting lower-amplitude, shorter-term variability. Two intervals of pronounced lake level drops occurred at similar to 110-108 +/- 5 and similar to 93-87 +/- 7 ka. They likely coincide with stadial conditions in the central Mediterranean (Melisey I and II pollen zones in Monticchio) and low global sea levels during Marine Isotope Stage (MIS) 5d and 5b. However, our data do not support the current hypothesis of an almost complete desiccation of the Dead Sea during the earlier of these lake level low stands based on a recovered gravel layer. Based on new petrographic analyses, we propose that, although it was a low stand, this well-sorted gravel layer may be a vestige of a thick turbidite that has been washed out during drilling rather than an in situ beach deposit. Two intervals of higher lake stands at similar to 108-93 +/- 6 and similar to 87-75 +/- 7 ka correspond to interstadial conditions in the central Mediterranean, i. e. pollen zones St. Germain I and II in Monticchio, and Greenland interstadials (GI) 24+23 and 21 in Greenland, as well as to sapropels S4 and S3 in the Mediterranean Sea. These apparent correlations suggest a close link of the climate in the Levant to North Atlantic and Mediterranean climates during the time of the build-up of Northern Hemisphere ice shields in the early last glacial period.
Subsurface microbial communities undertake many terminal electron-accepting processes, often simultaneously. Using a tritium-based assay, we measured the potential hydrogen oxidation catalyzed by hydrogenase enzymes in several subsurface sedimentary environments (Lake Van, Barents Sea, Equatorial Pacific, and Gulf of Mexico) with different predominant electron-acceptors. Hydrogenases constitute a diverse family of enzymes expressed by microorganisms that utilize molecular hydrogen as a metabolic substrate, product, or intermediate. The assay reveals the potential for utilizing molecular hydrogen and allows qualitative detection of microbial activity irrespective of the predominant electron-accepting process. Because the method only requires samples frozen immediately after recovery, the assay can be used for identifying microbial activity in subsurface ecosystems without the need to preserve live material. We measured potential hydrogen oxidation rates in all samples from multiple depths at several sites that collectively span a wide range of environmental conditions and biogeochemical zones. Potential activity normalized to total cell abundance ranges over five orders of magnitude and varies, dependent upon the predominant terminal electron acceptor. Lowest per-cell potential rates characterize the zone of nitrate reduction and highest per-cell potential rates occur in the methanogenic zone. Possible reasons for this relationship to predominant electron acceptor include (i) increasing importance of fermentation in successively deeper biogeochemical zones and (ii) adaptation of H(2)ases to successively higher concentrations of H-2 in successively deeper zones.
This publications-based thesis summarizes my contribution to the scientific field of ultrafast structural dynamics. It consists of 16 publications, about the generation, detection and coupling of coherent gigahertz longitudinal acoustic phonons, also called hypersonic waves. To generate such high frequency phonons, femtosecond near infrared laser pulses were used to heat nanostructures composed of perovskite oxides on an ultrashort timescale. As a consequence the heated regions of such a nanostructure expand and a high frequency acoustic phonon pulse is generated. To detect such coherent acoustic sound pulses I use ultrafast variants of optical Brillouin and x-ray scattering. Here an incident optical or x-ray photon is scattered by the excited sound wave in the sample. The scattered light intensity measures the occupation of the phonon modes.
The central part of this work is the investigation of coherent high amplitude phonon wave packets which can behave nonlinearly, quite similar to shallow water waves which show a steepening of wave fronts or solitons well known as tsunamis. Due to the high amplitude of the acoustic wave packets in the solid, the acoustic properties can change significantly in the vicinity of the sound pulse. This may lead to a shape change of the pulse. I have observed by time-resolved Brillouin scattering, that a single cycle hypersound pulse shows a wavefront steepening. I excited hypersound pulses with strain amplitudes until 1% which I have calibrated by ultrafast x-ray diffraction (UXRD).
On the basis of this first experiment we developed the idea of the nonlinear mixing of narrowband phonon wave packets which we call "nonlinear phononics" in analogy with the nonlinear optics, which summarizes a kaleidoscope of surprising optical phenomena showing up at very high electric fields. Such phenomena are for instance Second Harmonic Generation, four-wave-mixing or solitons. But in case of excited coherent phonons the wave packets have usually very broad spectra which make it nearly impossible to look at elementary scattering processes between phonons with certain momentum and energy.
For that purpose I tested different techniques to excite narrowband phonon wave packets which mainly consist of phonons with a certain momentum and frequency. To this end epitaxially grown metal films on a dielectric substrate were excited with a train of laser pulses. These excitation pulses drive the metal film to oscillate with the frequency given by their inverse temporal displacement and send a hypersonic wave of this frequency into the substrate. The monochromaticity of these wave packets was proven by ultrafast optical Brillouin and x-ray scattering.
Using the excitation of such narrowband phonon wave packets I was able to observe the Second Harmonic Generation (SHG) of coherent phonons as a first example of nonlinear wave mixing of nanometric phonon wave packets.
I am complicated
(2016)
Neisseria gonorrhoeae is one of the most prevalent sexually transmitted diseases worldwide with more than 100 million new infections per year. A lack of intense research over the last decades and increasing resistances to the recommended antibiotics call for a better understanding of gonococcal infection, fast diagnostics and therapeutic measures against N. gonorrhoeae. Therefore, the aim of this work was to identify novel immunogenic proteins as a first step to advance those unresolved problems. For the identification of immunogenic proteins, pHORF oligopeptide phage display libraries of the entire N. gonorrhoeae genome were constructed. Several immunogenic oligopeptides were identified using polyclonal rabbit antibodies against N. gonorrhoeae. Corresponding full-length proteins of the identified oligopeptides were expressed and their immunogenic character was verified by ELISA. The immunogenic character of six proteins was identified for the first time. Additional 13 proteins were verified as immunogenic proteins in N. gonorrhoeae.
Seit der Einführung von Antibiotika in die medizinische Behandlung von bakteriellen Infektionskrankheiten existiert ein Wettlauf zwischen der Evolution von Bakterienresistenzen und der Entwicklung wirksamer Antibiotika. Während bis in die 80er Jahre verstärkt an neuen Antibiotika geforscht wurde, gewinnen multiresistente Keime heute zunehmend die Oberhand. Um einzelne Pathogene erfolgreich nachzuweisen und zu bekämpfen, ist ein grundlegendes Wissen über den Erreger unumgänglich. Bakterielle Proteine, die bei einer Infektion vorrangig vom Immunsystem prozessiert und präsentiert werden, könnten für die Entwicklung von Impfstoffen oder gezielten Therapeutika nützlich sein. Auch für die Diagnostik wären diese immundominanten Proteine interessant. Allerdings herrscht ein Mangel an Wissen über spezifische Antigene vieler pathogener Bakterien, die eine eindeutige Diagnostik eines einzelnen Erregers erlauben würden.
Daher wurden in dieser Arbeit vier verschiedene Humanpathogene mittels Phage Display untersucht: Neisseria gonorrhoeae, Neisseria meningitidis, Borrelia burgdorferi und Clostridium difficile. Hierfür wurden aus der genomischen DNA der vier Erreger Bibliotheken konstruiert und durch wiederholte Selektion und Amplifikation, dem sogenannten Panning, immunogene Proteine isoliert. Für alle Erreger bis auf C. difficile wurden immunogene Proteine aus den jeweiligen Bibliotheken isoliert. Die identifizierten Proteine von N. meningitidis und B. burgdorferi waren größtenteils bekannt, konnten aber in dieser Arbeit durch Phage Display verifiziert werden. Für N. gonorrhoeae wurden 21 potentiell immunogene Oligopeptide isoliert, von denen sechs Proteine als neue zuvor unbeschriebene Proteine mit immunogenem Charakter identifiziert wurden. Von den Phagen-präsentierten Oligopeptide der 21 immunogenen Proteine wurden Epitopmappings mit verschiedenen polyklonalen Antikörpern durchgeführt, um immunogene Bereiche näher zu identifizieren und zu charakterisieren. Bei zehn Proteinen wurden lineare Epitope eindeutig mit drei polyklonalen Antikörpern identifiziert, von fünf weiteren Proteinen waren Epitope mit mindestens einem Antikörper detektierbar. Für eine weitere Charakterisierung der ermittelten Epitope wurden Alaninscans durchgeführt, die eine detaillierte Auskunft über kritische Aminosäuren für die Bindung des Antikörpers an das Epitop geben.
Ausgehend von dem neu identifizierten Protein mit immunogenem Charakter NGO1634 wurden 26 weitere Proteine aufgrund ihrer funktionellen Ähnlichkeit ausgewählt und mithilfe bioinformatischer Analysen auf ihre Eignung zur Entwicklung einer diagnostischen Anwendung analysiert. Durch Ausschluss der meisten Proteine aufgrund ihrer Lokalisation, Membrantopologie oder unspezifischen Proteinsequenz wurden scFv-Antikörper gegen acht Proteine mittels Phage Display generiert und anschließend als scFv-Fc-Fusionsantikörper produziert und charakterisiert.
Die hier identifizierten Proteine und linearen Epitope könnten einen Ansatzpunkt für die Entwicklung einer diagnostischen oder therapeutischen Anwendung bieten. Lineare Epitopsequenzen werden häufig für die Impfstoffentwicklung eingesetzt, sodass vor allem die in dieser Arbeit bestimmten Epitope von Membranproteinen interessante Kandidaten für weitere Untersuchungen in diese Richtung sind. Durch weitere Untersuchungen könnten möglicherweise unbekannte Virulenzfaktoren entdeckt werden, deren Inhibierung einen entscheidenden Einfluss auf Infektionen haben könnten.
Für alle Organismen ist die Aufrechterhaltung ihres energetischen Gleichgewichts unter fluktuierenden Umweltbedingungen lebensnotwendig. In Eukaryoten steuern evolutionär konservierte Proteinkinasen, die in Pflanzen als SNF1-RELATED PROTEIN KINASE1 (SnRK1) bezeichnet werden, die Adaption an Stresssignale aus der Umwelt und an die Limitierung von Nährstoffen und zellulärer Energie. Die Aktivierung von SnRK1 bedingt eine umfangreiche transkriptionelle Umprogrammierung, die allgemein zu einer Repression energiekonsumierender Prozesse wie beispielsweise Zellteilung und Proteinbiosynthese und zu einer Induktion energieerzeugender, katabolischer Stoffwechselwege führt. Wie unterschiedliche Signale zu einer generellen sowie teilweise gewebe- und stressspezifischen SnRK1-vermittelten Antwort führen ist bisher noch nicht ausreichend geklärt, auch weil bislang nur wenige Komponenten der SnRK1-Signaltransduktion identifiziert wurden. In dieser Arbeit konnte ein Protein-Protein-Interaktionsnetzwerk um die SnRK1αUntereinheiten aus Arabidopsis AKIN10/AKIN11 etabliert werden. Dadurch wurden zunächst Mitglieder der pflanzenspezifischen DUF581-Proteinfamilie als Interaktionspartner der SnRK1α-Untereinheiten identifiziert. Diese Proteine sind über ihre konservierte DUF581Domäne, in der ein Zinkfinger-Motiv lokalisiert ist, fähig mit AKIN10/AKIN11 zu interagieren. In planta Ko-Expressionsanalysen zeigten, dass die DUF581-Proteine eine Verschiebung der nucleo-cytoplasmatischen Lokalisierung von AKIN10 hin zu einer nahezu ausschließlichen zellkernspezifischen Lokalisierung begünstigen sowie die Ko-Lokalisierung von AKIN10 und DUF581-Proteinen im Nucleus. In Bimolekularen Fluoreszenzkomplementations-Analysen konnte die zellkernspezifische Interaktion von DUF581-Proteinen mit SnRK1α-Untereinheiten in planta bestätigt werden. Außerhalb der DUF581-Domäne weisen die Proteine einander keine große Sequenzähnlichkeit auf. Aufgrund ihrer Fähigkeit mit SnRK1 zu interagieren, dem Fehlen von SnRK1Phosphorylierungsmotiven sowie ihrer untereinander sehr variabler gewebs-, entwicklungs- und stimulusspezifischer Expression wurde für DUF581-Proteine eine Funktion als Adaptoren postuliert, die unter bestimmten physiologischen Bedingungen spezifische Substratproteine in den SnRK1-Komplex rekrutieren. Auf diese Weise könnten DUF581Proteine die Interaktion von SnRK1 mit deren Zielproteinen modifizieren und eine Feinjustierung der SnRK1-Signalweiterleitung ermöglichen. Durch weiterführende Interaktionsstudien konnten DUF581-interagierende Proteine darunter Transkriptionsfaktoren, Proteinkinasen sowie regulatorische Proteine gefunden werden, die teilweise ebenfalls Wechselwirkungen mit SnRK1α-Untereinheiten aufzeigten. Im Rahmen dieser Arbeit wurde eines dieser Proteine für das eine Beteiligung an der SnRK1Signalweiterleitung als Transkriptionsregulator vermutet wurde näher charakterisiert. STKR1 (STOREKEEPER RELATED 1), ein spezifischer Interaktionspartner von DUF581-18, gehört zu einer pflanzenspezifischen Leucin-Zipper-Transkriptionsfaktorfamilie und interagiert in Hefe sowie in planta mit SnRK1. Die zellkernspezifische Interaktion von STKR1 und AKIN10 in Pflanzen unterstützt die Vermutung der kooperativen Regulation von Zielgenen. Weiterhin stabilisierte die Anwesenheit von AKIN10 die Proteingehalte von STKR1, das wahrscheinlich über das 26S Proteasom abgebaut wird. Da es sich bei STKR1 um ein Phosphoprotein mit SnRK1-Phosphorylierungsmotiv handelt, stellt es sehr wahrscheinlich ein SnRK1-Substrat dar. Allerdings konnte eine SnRK1-vermittelte Phosphorylierung von STKR1 in dieser Arbeit nicht gezeigt werden. Der Verlust von einer Phosphorylierungsstelle beeinflusste die Homo- und Heterodimerisierungsfähigkeit von STKR1 in Hefeinteraktionsstudien, wodurch eine erhöhte Spezifität der Zielgenregulation ermöglicht werden könnte. Außerdem wurden Arabidopsis-Pflanzen mit einer veränderten STKR1-Expression phänotypisch, physiologisch und molekularbiologisch charakterisiert. Während der Verlust der STKR1-Expression zu Pflanzen führte, die sich kaum von Wildtyp-Pflanzen unterschieden, bedingte die konstitutive Überexpression von STKR1 ein stark vermindertes Pflanzenwachstum sowie Entwicklungsverzögerungen hinsichtlich der Blühinduktion und Seneszenz ähnlich wie sie auch bei SnRK1α-Überexpression beschrieben wurden. Pflanzen dieser Linien waren nicht in der Lage Anthocyane zu akkumulieren und enthielten geringere Gehalte an Chlorophyll und Carotinoiden. Neben einem erhöhten nächtlichen Stärkeumsatz waren die Pflanzen durch geringere Saccharosegehalte im Vergleich zum Wildtyp gekennzeichnet. Eine Transkriptomanalyse ergab, dass in den STKR1-überexprimierenden Pflanzen unter Energiemangelbedingungen, hervorgerufen durch eine verlängerte Dunkelphase, eine größere Anzahl an Genen im Vergleich zum Wildtyp differentiell reguliert war als während der Lichtphase. Dies spricht für eine Beteiligung von STKR1 an Prozessen, die während der verlängerten Dunkelphase aktiv sind. Ein solcher ist beispielsweise die SnRK1-Signaltransduktion, die unter energetischem Stress aktiviert wird. Die STKR1Überexpression führte zudem zu einer verstärkten transkriptionellen Induktion von Abwehrassoziierten Genen sowie NAC- und WRKY-Transkriptionsfaktoren nach verlängerter Dunkelphase. Die Transkriptomdaten deuteten auf eine stimulusunabhängige Induktion von Abwehrprozessen hin und konnten eine Erklärung für die phänotypischen und physiologischen Auffälligkeiten der STKR1-Überexprimierer liefern.
Background
Dietary calcium (Ca) concentrations might affect regulatory pathways within the Ca and vitamin D metabolism and consequently excretory mechanisms. Considering large variations in Ca concentrations of feline diets, the physiological impact on Ca homeostasis has not been evaluated to date. In the present study, diets with increasing concentrations of dicalcium phosphate were offered to ten healthy adult cats (Ca/phosphorus (P): 6.23/6.02, 7.77/7.56, 15.0/12.7, 19.0/17.3, 22.2/19.9, 24.3/21.6 g/kg dry matter). Each feeding period was divided into a 10-day adaptation and an 8-day sampling period in order to collect urine and faeces. On the last day of each feeding period, blood samples were taken.
Results
Urinary Ca concentrations remained unaffected, but faecal Ca concentrations increased (P < 0.001) with increasing dietary Ca levels. No effect on whole and intact parathyroid hormone levels, fibroblast growth factor 23 and calcitriol concentrations in the blood of the cats were observed. However, the calcitriol precursors 25(OH)D-2 and 25(OH)D-3, which are considered the most useful indicators for the vitamin D status, decreased with higher dietary Ca levels (P = 0.013 and P = 0.033). Increasing dietary levels of dicalcium phosphate revealed an acidifying effect on urinary fasting pH (6.02) and postprandial pH (6.01) (P < 0.001), possibly mediated by an increase of urinary phosphorus (P) concentrations (P < 0.001).
Conclusions
In conclusion, calcitriol precursors were linearly affected by increasing dietary Ca concentrations. The increase in faecal Ca excretion indicates that Ca homeostasis of cats is mainly regulated in the intestine and not by the kidneys. Long-term studies should investigate the physiological relevance of the acidifying effect observed when feeding diets high in Ca and P.
Ongoing climate change is known to cause an increase in the frequency and amplitude of local temperature and precipitation extremes in many regions of the Earth. While gradual changes in the climatological conditions have already been shown to strongly influence plant flowering dates, the question arises if and how extremes specifically impact the timing of this important phenological phase. Studying this question calls for the application of statistical methods that are tailored to the specific properties of event time series. Here, we employ event coincidence analysis, a novel statistical tool that allows assessing whether or not two types of events exhibit similar sequences of occurrences in order to systematically quantify simultaneities between meteorological extremes and the timing of the flowering of four shrub species across Germany. Our study confirms previous findings of experimental studies by highlighting the impact of early spring temperatures on the flowering of the investigated plants. However, previous studies solely based on correlation analysis do not allow deriving explicit estimates of the strength of such interdependencies without further assumptions, a gap that is closed by our analysis. In addition to direct impacts of extremely warm and cold spring temperatures, our analysis reveals statistically significant indications of an influence of temperature extremes in the autumn preceding the flowering.
This dissertation examines the impact of the type of referring expression on the acquisition of word order variation in German-speaking preschoolers. A puzzle in the area of language acquisition concerns the production-comprehension asymmetry for non-canonical sentences like "Den Affen fängt die Kuh." (“The monkey, the cow chases.”), that is, preschoolers usually have difficulties in accurately understanding non-canonical sentences approximately until age six (e.g., Dittmar et al., 2008) although they produce non-canonical sentences already around age three (e.g., Poeppel & Wexler, 1993; Weissenborn, 1990). This dissertation investigated the production and comprehension of non-canonical sentences to address this issue.
Three corpus analyses were conducted to investigate the impact of givenness, topic status and the type of referring expression on word order in the spontaneous speech of two- to four-year-olds and the child-directed speech produced by their mothers. The positioning of the direct object in ditransitive sentences was examined; in particular, sentences in which the direct object occurred before or after the indirect object in the sentence-medial positions and sentences in which it occurred in the sentence-initial position. The results reveal similar ordering patterns for children and adults. Word order variation was to a large extent predictable from the type of referring expression, especially with respect to the word order involving the sentence-medial positions. Information structure (e.g., topic status) had an additional impact only on word order variation that involved the sentence-initial position.
Two comprehension experiments were conducted to investigate whether the type of referring expression and topic status influences the comprehension of non-canonical transitive sentences in four- and five-year-olds. In the first experiment, the topic status of the one of the sentential arguments was established via a preceding context sentence, and in the second experiment, the type of referring expression for the sentential arguments was additionally manipulated by using either a full lexical noun phrase (NP) or a personal pronoun. The results demonstrate that children’s comprehension of non-canonical sentences improved when the topic argument was realized as a personal pronoun and this improvement was independent of the grammatical role of the arguments. However, children’s comprehension was not improved when the topic argument was realized as a lexical NP.
In sum, the results of both production and comprehension studies support the view that referring expressions may be seen as a sentence-level cue to word order and to the information status of the sentential arguments. The results highlight the important role of the type of referring expression on the acquisition of word order variation and indicate that the production-comprehension asymmetry is reduced when the type of referring expression is considered.
Aim: We aimed to identify patient characteristics and comorbidities that correlate with the initial exercise capacity of
cardiac rehabilitation (CR) patients and to study the significance of patient characteristics, comorbidities and training
methods for training achievements and final fitness of CR patients.
Methods: We studied 557 consecutive patients (51.7 Æ 6.9 years; 87.9% men) admitted to a three-week in-patient CR.
Cardiopulmonary exercise testing (CPX) was performed at discharge. Exercise capacity (watts) at entry, gain in training
volume and final physical fitness (assessed by peak O 2 utilization (VO 2peak ) were analysed using analysis of covariance
(ANCOVA) models.
Results: Mean training intensity was 90.7 Æ 9.7% of maximum heart rate (81% continuous/19% interval training, 64%
additional strength training). A total of 12.2 Æ 2.6 bicycle exercise training sessions were performed. Increase of training
volume by an average of more than 100% was achieved (difference end/beginning of CR: 784 Æ 623 watts  min). In the
multivariate model the gain in training volume was significantly associated with smoking, age and exercise capacity at
entry of CR. The physical fitness level achieved at discharge from CR as assessed by VO 2peak was mainly dependent on
age, but also on various factors related to training, namely exercise capacity at entry, increase of training volume and
training method.
Conclusion: CR patients were trained in line with current guidelines with moderate-to-high intensity and reached a
considerable increase of their training volume. The physical fitness level achieved at discharge from CR depended on
various factors associated with training, which supports the recommendation that CR should be offered to all cardiac
patients.
Prevalence of Achilles tendinopathy increases with age, leading to a weaker tendon with predisposition to rupture. Previous studies, investigating Achilles tendon (AT) properties, are restricted to standardized isometric conditions. Knowledge regarding the influence of age and pa-thology on AT response under functional tasks remains limited. Therefore, the aim of the thesis was to investigate the influence of age and pathology on AT properties during a single-leg vertical jump.
Healthy children, asymptomatic adults and patients with Achilles tendinopathy participated. Ultrasonography was used to assess AT-length, AT-cross-sectional area and AT-elongation. The reliability of the methodology used was evaluated both Intra- and inter-rater at rest and at maximal isometric plantar-flexion contraction and was further implemented to investigate tendon properties during functional task. During the functional task a single-leg vertical jump on a force plate was performed while simultaneously AT elongation and vertical ground reaction forces were recorded. AT compliance [mm/N] (elongation/force) and AT strain [%] (elongation/length) were calculated. Differences between groups were evaluated with respect to age (children vs. adults) and pathology (asymptomatic adults vs. patients).
Good to excellent reliability with low levels of variability was achieved in the assessment of AT properties. During the jumps AT elongation was found to be statistical significant higher in children. However, no statistical significant difference was found for force among the groups. AT compliance and strain were found to be statistical significant higher only in children. No significant differences were found between asymptomatic adults and patients with tendinopathy.
The methodology used to assess AT properties is reliable, allowing its implementation into further investigations. Higher AT-compliance in children might be considered as a protective factor against load-related injuries. During functional task, when higher forces are acting on the AT, tendinopathy does not result in a weaker tendon.
Background
Overweight and obesity are increasing health problems that are not restricted to adults only. Childhood obesity is associated with metabolic, psychological and musculoskeletal comorbidities. However, knowledge about the effect of obesity on the foot function across maturation is lacking. Decreased foot function with disproportional loading characteristics is expected for obese children. The aim of this study was to examine foot loading characteristics during gait of normal-weight, overweight and obese children aged 1-12 years.
Methods
A total of 10382 children aged one to twelve years were enrolled in the study. Finally, 7575 children (m/f: n = 3630/3945; 7.0 +/- 2.9yr; 1.23 +/- 0.19m; 26.6 +/- 10.6kg; BMI: 17.1 +/- 2.4kg/m(2)) were included for (complete case) data analysis. Children were categorized to normalweight (>= 3rd and <90th percentile; n = 6458), overweight (>= 90rd and <97th percentile; n = 746) or obese (>97th percentile; n = 371) according to the German reference system that is based on age and gender-specific body mass indices (BMI). Plantar pressure measurements were assessed during gait on an instrumented walkway. Contact area, arch index (AI), peak pressure (PP) and force time integral (FTI) were calculated for the total, fore-, mid-and hindfoot. Data was analyzed descriptively (mean +/- SD) followed by ANOVA/Welch-test (according to homogeneity of variances: yes/no) for group differences according to BMI categorization (normal-weight, overweight, obesity) and for each age group 1 to 12yrs (post-hoc Tukey Kramer/Dunnett's C; alpha = 0.05).
Results
Mean walking velocity was 0.95 +/- 0.25 m/s with no differences between normal-weight, overweight or obese children (p = 0.0841). Results show higher foot contact area, arch index, peak pressure and force time integral in overweight and obese children (p< 0.001). Obese children showed the 1.48-fold (1 year-old) to 3.49-fold (10 year-old) midfoot loading (FTI) compared to normal-weight.
Conclusion
Additional body mass leads to higher overall load, with disproportional impact on the midfoot area and longitudinal foot arch showing characteristic foot loading patterns. Already the feet of one and two year old children are significantly affected. Childhood overweight and obesity is not compensated by the musculoskeletal system. To avoid excessive foot loading with potential risk of discomfort or pain in childhood, prevention strategies should be developed and validated for children with a high body mass index and functional changes in the midfoot area. The presented plantar pressure values could additionally serve as reference data to identify suspicious foot loading patterns in children.
Mit der Patientenmobilitätsrichtlinie (2011/24/EU) wurde eine verbindliche gesetzliche Grundlage geschaffen, im Bereich der hochspezialisierten Gesundheitsversorgung freiwillig und in strukturierter Form in europäischen Referenznetzwerken (ERN) von Gesundheits-dienstleistern und Fachzentren zusammenzuarbeiten. Dabei kommt dem Austausch von Fachwissen eine besondere Bedeutung zu. Diese qualitative Studie geht der Frage nach, wel-che wesentlichen Faktoren den Informations- und Wissensaustausch sowie das Lernen in Netzwerken beeinflussen und wie diese gefördert werden können. Es werden Netzwerkkoor-dinatoren und deren steuernde Einheiten in den hochspezialisierten Versorgungsbereichen Krebs und Seltene Erkrankungen in Deutschland und in Frankreich sowie auf europäischer Ebene befragt. Die Studie wird durch einen Literaturvergleich von bi- und trilateralen Ge-sundheitskooperationen mit multilateralen Netzwerken ergänzt. Für die ERN wird die zentra-le Bedeutung der digitalen Medien und Technologien herausgearbeitet sowie die Empfeh-lung ausgesprochen, die ERN ein systematisches Wissensverwendungs- und -generierungskonzept erarbeiten zu lassen. Durch die zukünftigen ERN wird die vernetzte Informationsgesellschaft Einzug in die medizinische Praxis halten.
Since 1998, elite athletes’ sport injuries have been monitored in single sport event, which leads to the development of first comprehensive injury surveillance system in multi-sport Olympic Games in 2008. However, injury and illness occurred in training phases have not been systematically studied due to its multi-facets, potentially interactive risk related factors. The present thesis aim to address issues of feasibility of establishing a validated measure for injury/illness, training environment and psychosocial risk factors by creating the evaluation tool namely risk of injury questionnaire (Risk-IQ) for elite athletes, which based on IOC consensus statement 2009 recommended content of preparticipation evaluation(PPE) and periodic health exam (PHE).
A total of 335 top level athletes and a total of 88 medical care providers from Germany and Taiwan participated in tow “cross-sectional plus longitudinal” Risk-IQ and MCPQ surveys respectively. Four categories of injury/illness related risk factors questions were asked in Risk-IQ for athletes while injury risk and psychological related questions were asked in MCPQ for MCP cohorts. Answers were quantified scales wise/subscales wise before analyzed with other factors/scales. In addition, adapted variables such as sport format were introduced for difference task of analysis.
Validated with 2-wyas translation and test-retest reliabilities, the Risk-IQ was proved to be in good standard which were further confirmed by analyzed results from official surveys in both Germany and Taiwan. The result of Risk-IQ revealed that elite athletes’ accumulated total injuries, in general, were multi-factor dependent; influencing factors including but not limited to background experiences, medical history, PHE and PPE medical resources as well as stress from life events. Injuries of different body parts were sport format and location specific. Additionally, medical support of PPE and PHE indicated significant difference between German and Taiwan.
The result of the present thesis confirmed that it is feasible to construct a comprehensive evalua-tion instrument for heterogeneous elite athletes cohorts’ risk factor analysis for injury/illness oc-curred during their non-competition periods. In average and with many moderators involved, Ger-man elite athletes have superior medical care support yet suffered more severe injuries than Tai-wanese counterparts. Opinions of injury related psychological issues reflected differently on vari-ous MCP groups irrespective of different nationalities. In general, influencing factors and interac-tions existed among relevant factors in both studies which implied further investigation with multiple regression analysis is needed for better understanding.
Background:
Environmental stress puts organisms at risk and requires specific stress-tailored responses to maximize
survival. Long-term exposure to stress necessitates a global reprogramming of the cellular activities at different
levels of gene expression.
Results:
Here, we use ribosome profiling and RNA sequencing to globally profile the adaptive response of
Arabidopsis thaliana
to prolonged heat stress. To adapt to long heat exposure, the expression of many genes is
modulated in a coordinated manner at a transcriptional and translational level. However, a significant group of
genes opposes this trend and shows mainly translational regulation. Different secondary structure elements are
likely candidates to play a role in regulating translation of those genes.
Conclusions:
Our data also uncover on how the subunit stoichiometry of multimeric protein complexes in plastids
is maintained upon heat exposure.