Refine
Has Fulltext
- yes (509) (remove)
Year of publication
- 2016 (509) (remove)
Document Type
- Postprint (215)
- Doctoral Thesis (136)
- Article (68)
- Monograph/Edited Volume (26)
- Preprint (17)
- Part of Periodical (16)
- Master's Thesis (12)
- Review (6)
- Conference Proceeding (5)
- Bachelor Thesis (2)
Is part of the Bibliography
- yes (509) (remove)
Keywords
- model (6)
- climate-change (5)
- sentence processing (5)
- Europe (4)
- German (4)
- Klimawandel (4)
- aggression (4)
- climate change (4)
- evolution (4)
- language (4)
Institute
- Mathematisch-Naturwissenschaftliche Fakultät (79)
- Institut für Geowissenschaften (40)
- Humanwissenschaftliche Fakultät (39)
- Institut für Chemie (39)
- Institut für Physik und Astronomie (31)
- Institut für Biochemie und Biologie (30)
- Bürgerliches Recht (28)
- Department Linguistik (20)
- Department Psychologie (20)
- Institut für Mathematik (19)
The current study investigates an interaction between numbers and physical size (i.e. size congruity) in visual search. In three experiments, participants had to detect a physically large (or small) target item among physically small (or large) distractors in a search task comprising single-digit numbers. The relative numerical size of the digits was varied, such that the target item was either among the numerically large or small numbers in the search display and the relation between numerical and physical size was either congruent or incongruent. Perceptual differences of the stimuli were controlled by a condition in which participants had to search for a differently coloured target item with the same physical size and by the usage of LCD-style numbers that were matched in visual similarity by shape transformations. The results of all three experiments consistently revealed that detecting a physically large target item is significantly faster when the numerical size of the target item is large as well (congruent), compared to when it is small (incongruent). This novel finding of a size congruity effect in visual search demonstrates an interaction between numerical and physical size in an experimental setting beyond typically used binary comparison tasks, and provides important new evidence for the notion of shared cognitive codes for numbers and sensorimotor magnitudes. Theoretical consequences for recent models on attention, magnitude representation and their interactions are discussed.
„Was ist Migration?“
(2016)
Auch wenn die Appelle, die Bedeutung von Migration für Erwachsenenbildung deutlicher wahrzunehmen, unüberhörbar sind, bleiben sie bezüglich kategorialer Arbeit bemerkenswert wenig beachtet. Grundlagentheoretisch motivierte Arbeit am Begriff „Migration“ ist in der Erwachsenenbildung noch lange nicht hinreichend ausgeschöpft. Auch wenn sich einzelne Studien mit ihm auseinandersetzen, besteht dennoch der Eindruck, dass kategoriale Klärungsversuche singulär bleiben. Die nicht einfache Aufgabe, den Begriff Migration vor seiner kategorialen Stilllegung zu bewahren, bleibt eine ernsthafte Herausforderung für erwachsenenpädagogische Migrationsforschung, sofern sie daran interessiert ist, die Risiken eines bisher essentialistischen Kurses ernsthaft ins Visier zu nehmen.
Portal alumni
(2016)
Die Universität Potsdam hat in diesem Jahr groß gefeiert: Sie ist 25 Jahre alt geworden. Zahlreiche Veranstaltungen und Publikationen zum Jubeljahr beleuchten, wie sich die Universität seit ihrer Gründung am 15. Juli 1991 entwickelt hat. Auch die Redaktion von Portal Alumni will dieses Vierteljahrhundert in den Blick nehmen und zwar aus der Perspektive der Studierenden und Alumni. Wir haben uns gefragt: Wie hat sich das Studium an der Universität Potsdam in der Vergangenheit geändert? Was ist den Studierenden heute wichtig, was waren wichtige Themen vor zehn oder zwanzig Jahren? Welche Erinnerungen haben Alumni an ihre Hochschulzeit? In diesem Heft lassen wir Alumni zu Wort kommen, die zu unterschiedlichen Zeiten an der Universität studiert haben und die für uns einen Blick zurück werfen auf ihre Generation. Mit dabei ist etwa Stefan Uhlmann, der sein Studium kurz vor dem Wendeherbst aufgenommen hatte. Sein erstes Semester war noch geprägt von sozialer Sicherheit: Der Staat zahlte den monatlichen studentischen Unterhalt von 200 Mark, die Universität stellte den Wohnheimplatz. Selbst der Arbeitsplatz war nach den Gesetzen der Planwirtschaft sicher. Wenige Monate später war alles anders: Die Inhalte aller Studiengänge wurden auf den Prüfstand gestellt, alle Rahmenbedingungen neu gestaltet, die gesamte Gesellschaft und damit auch der Arbeitsmarkt waren im Umbruch. Zwischen der Generation von Stefan Uhlmann und der der jungen Bachelorabsolventin Friederike Bath liegen 25 Jahre Universitätsgeschichte. Eine Zeit, in der sich Lehre und Studium gewandelt haben. Der Einführung von einer Studienordnung nach bundesdeutschem Recht folgte in der Jahrtausendwende die Bologna-Reform, die nicht nur das Studieren verändert hat. Sie hat auch einen Wertewandel mit sich gebracht, den der Sozialisationswissenschaftler Wilfried Schubarth in dieser Ausgabe beschreibt.
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.
Turbidity measurements are frequently implemented for the monitoring of heterogeneous chemical, physical, or biotechnological processes. However, for quantitative measurements, turbidity probes need calibration, as is requested and regulated by the ISO 7027:1999. Accordingly, a formazine suspension has to be produced. Despite this regulatory demand, no scientific publication on the stability and reproducibility of this polymerization process is available. In addition, no characterization of the optical properties of this calibration material with other optical methods had been achieved so far. Thus, in this contribution, process conditions such as temperature and concentration have been systematically investigated by turbidity probe measurements and Photon Density Wave (PDW) spectroscopy, revealing an influence on the temporal formazine formation onset. In contrast, different reaction temperatures do not lead to different scattering properties for the final formazine suspensions, but give an access to the activation energy for this condensation reaction. Based on PDW spectroscopy data, the synthesis of formazine is reproducible. However, very strong influences of the ambient conditions on the measurements of the turbidity probe have been observed, limiting its applicability. The restrictions of the turbidity probe with respect to scatterer concentration are examined on the basis of formazine and polystyrene suspensions. Compared to PDW spectroscopy data, signal saturation is observed at already low reduced scattering coefficients.
Portal Wissen = small
(2016)
Let’s be honest: even science wants to make it big, at least when it comes to discovering new knowledge. Yet if one thing belongs in the annals of successful research, it is definitely small things. Scientists have long understood that their job is to explore things that they don’t see right away. Seneca once wrote, “If something is smaller than the great, this does not mean at all that it is insignificant.”
The smallest units of life, such as bacteria or viruses, can often have powerful effects. And again and again, (seemingly) large things must first be disassembled or reduced to small pieces in order to recognize their nature. One of the greatest secrets of our world – the atom, the smallest, if no longer indivisible, unit of chemical elements – revealed itself only by looking at its diminutive size. By no means is ‘small’ (German: klein) merely a counterpoint to large, at least in linguistic terms; the word comes from West Germanic klaini, which means ‘fine’ or ‘delicate,’ and is also related to the English word ‘clean.’ Fine and clean – certainly something worth striving for in scientific work. And a bit of attention to detail doesn’t hurt either.
This doesn’t mean that researchers can be smallminded; they should be ready to expect the unexpected and to adjust their work accordingly. And even if they cannot attain their goals in the short term, they need staying power to keep themselves from being talked down, from giving up.
Strictly speaking, research is like putting together a puzzle with tons of tiny pieces; you don’t want it to end. Every discovery worthy of a Nobel Prize, every major research project, has to start with a small idea, with a tiny spark, and then the planning of the minutest details can begin. What follows is work focused on minuscule details: hours of interviews searching for the secret of the cerebellum (Latin for ‘little brain’), days of field studies searching for Lilliputian forms of life, weeks of experimentation meant to render visible the microscopically tiny, months of archival research that brings odds and ends to light, or years of reading fine print. All while hunting for a big hit...
This is why we’ve assembled a few ‘little’ stories about research at the University of Potsdam, under the motto: small, but look out! Nutritional scientists are working on rescuing some of the earth’s smaller residents – mice – from the fate of ‘lab rats’ by developing alternatives to animal testing. Linguists are using innovative methods in several projects to investigate how small children learn languages. Astrophysicists in Potsdam are scanning the skies above Babelsberg for the billions of stars in the Magellan Cloud, which only seem tiny from down here. The Research Center Sanssouci, initiated by the Prussian Palaces and Gardens Foundation and the University of Potsdam, is starting small but will bring about great things for Potsdam’s cultural landscape. Biologists are drilling down to the smallest building blocks of life, looking for genes in barley so that new strains with positive characteristics can be cultivated.
Like we said: little things. Have fun reading!
The Editorial
Portal Wissen = Point
(2016)
A point is more than meets the eye. In geometry, a point is an object with zero dimensions – it is there but takes up little space. You may assume that something so small is easily overlooked. A closer look reveals that points are everywhere and play a significant role in many areas. In physics, for example, a mass point is the highest possible idealization of a body, which is the theoretical notion that the entire mass of a body is concentrated in a point, its “center of mass”.
Points are at the beginning (starting points), at intersections (pivot points), and at the end (final points). A point symbolizes great precision. There is a reason we “get to the point”. In writing, a point abbreviates, structures, and finalizes what is said. Physicians puncture, and athletes collect points on playing fields, courses, and on tables.
It’s no wonder that researchers are “surrounded” by points and work with them every day: Points bring order to chaos, structure the unexplained, and name the nameless. A point is often the beginning, an entry to worlds, findings, or problems.
Points are for everyone, though. German mathematician Oskar Perron wrote, “A point is exactly what the intelligent yet innocent, uncorrupted reader imagines it to be.” We want to follow up on this quotation: The latest edition of Portal Wissen offers exciting starting points, analyzes points of view, and gets right to the point.
We follow a physicist to the sun – the center point of our solar system – to ponder the origin of solar eruptions. We talked to a marketing professor about turning contentious points into successful deals during negotiation. Business information experts present leverage points that prepare both humans and machines for factories in the age of Industry 4.0. Enthusiastic entrepreneurs show us how their research became the starting point of a successful business idea – and also make the world a bit better. Geoscientists explain why the weather phenomenon El Niño causes – wet and dry – flashpoints. Just to name a few of many points …
We hope our magazine scores points with you and wish you an inspiring read!
The Editorial
Portal Wissen = klein
(2016)
Seien wir mal ehrlich: Auch Wissenschaft hat das Ziel, groß rauszukommen, zumindest im Namen der Erkenntnis. Dabei gilt doch: Wenn etwas ins Stammbuch erfolgreicher Forschung gehört, dann ist es wohl die Vorstellung vom Kleinen. Schließlich ist es schon immer ihr Selbstverständnis gewesen, das zu ergründen, was sich nicht auf den ersten Blick erschließt. Schon Seneca war der Ansicht: „Wenn etwas kleiner ist als das Große, so ist es darum noch lange nicht unbedeutend.“
Kleinste Einheiten des Lebens wie Bakterien oder Viren bewirken Gewaltiges. Und immer wieder müssen (scheinbar) große Dinge erst ver- oder zerkleinert werden, um ihre Natur zu erkennen. Eines der größten Geheimnisse unserer Welt – das Atom als kleinste, wenn auch (nicht mehr) unteilbare Einheit der chemischen Elemente – hat sich erst beim Blick auf Winzigkeiten offenbart. Dabei war klein mitnichten immer nur das Gegenstück zu groß. Zumindest sprachlich, denn das Wort geht auf das westgermanische klaini zurück, das so viel wie „fein“ und „zierlich“ bedeutet, und ist darüber hinaus auch mit dem englischen clean, also „sauber“, verwandt. Fein und sauber – durchaus ein erstrebenswertes Credo für wissenschaftliches Arbeiten. Auch ein wenig Kleinlichkeit schadet nicht.
Dabei darf ein Forscher beileibe kein Kleingeist, sondern sollte bereit sein, das Unvermutete zu ahnen und seine Arbeit entsprechend darauf auszurichten. Und wenn das Ziel nicht kurzfristig zu erreichen ist, braucht es den namhaften langen Atem, sich nicht kleinreden zu lassen und klein beizugeben.
Genau genommen ist Forschung eigentlich ein nicht enden wollendes Klein-klein. Jede nobelpreiswürdige Entdeckung, jedes Großforschungsprojekt muss mit einer kleinen Idee, einem Fünklein beginnen, nur um anschließend bis ins Kleinste durchgeplant zu werden. Was folgt, die Niederungen der Ebene, ist Kleinarbeit: stundenlange Interviews auf der Suche nach dem Geheimnis des Kleinhirns, tagelange Feldstudien, die Kleinstlebewesen nachspüren, wochenlange Experimentreihen, die das mikroskopisch Kleine sichtbar machen sollen, monatelange Archivrecherche, die Kleinkram zutage fördert, oder jahrelange Lektüre des Kleingedruckten. All das auf der Jagd nach dem großen Wurf …
Darum haben wir Ihnen ein paar „Kleinigkeiten“ aus der Forschung an der Universität Potsdam zusammengestellt, ganz nach dem Motto: Klein, aber oho! So arbeiten Ernährungswissenschaftler daran, einigen der kleineren Erdenbewohner – den Mäusen – das Schicksal von „Laborratten“ zu ersparen, indem sie Alternativen zu Tierversuchen entwickeln. Wie Hänschen klein Sprachen lernt, untersuchen Sprachwissenschaftler gleich in mehreren Projekten und mit innovativen Methoden. Nur scheinbar klitzeklein sind dagegen die Milliarden von Sternen der Magellanschen Wolken, die Potsdamer Astrophysiker im Blick haben – vom Babelsberg aus. Die Geowissenschaftler des Graduiertenkollegs „StRATEGy“ wiederum waren vor Ort in Argentinien, um das (Klein-)„Kind“ – das Wetterphänomen El Niño – und seine Ursachen einmal genauer unter die Lupe zu nehmen. Klein anfangen, aber (die Potsdamer Kulturlandschaft) groß rausbringen soll das Research Center Sanssouci, das die Stiftung Preußische Schlösser und Gärten und die Universität Potsdam gemeinsam initiiert haben. Schließlich zeigen wir, dass schon jetzt eine ganze Reihe von Projekten und Initiativen angeschoben wird, um 2019 ein Kleinod der Region neu zu entdecken: den Wanderer durch die Mark, Theodor Fontane.
Wie gesagt: Kleinigkeiten. Wir wünschen viel Spaß beim Lesen!
Die Redaktion
Portal Wissen = Punkt
(2016)
Ein Punkt hat es in sich, auch wenn man es ihm nicht unbedingt ansieht. Immerhin gilt er in der Geometrie als Objekt ohne Ausdehnung – etwas, das da ist, aber sich nicht „breit macht“. Man sollte annehmen, was so klein ist, wird leicht übersehen. Aber Punkte sind, wenn man genauer hinschaut, nicht nur überall zu finden, sondern auch präsent und spielen gewichtige Rollen. In der Physik etwa ist ein Massepunkt die höchstmögliche Idealisierung eines realen Körpers: Er beschreibt die – theoretische – Vorstellung, die gesamte Masse des Körpers wäre in einem Punkt, seinem Schwerpunkt, vereinigt. Punkte finden sich am Anfang (Ausgangspunkt), an den Übergängen (Dreh- und Angelpunkt) und am Ende (Schlusspunkt). Ein Punkt ist das Symbol größter Präzision, nicht umsonst kommt man sprichwörtlich „auf den Punkt“. Als Bestandteil unserer Schrift kürzt er ab, gliedert und bringt Gesagtes zu Ende. Sogar Musiker und Mediziner punktieren. Und Sportler aller Arten sammeln Punkte auf Plätzen, Bahnen und in Tabellen.
Kein Wunder, dass gerade Wissenschaftler von Punkten „umgeben“ sind und täglich mit ihnen arbeiten: Sie bringen Ordnung ins Chaos, strukturieren das Unerklärte, benennen das Namenlose. Allzu oft macht ein Punkt den Anfang, von dem aus sich Zugänge eröffnen, zu Welten, Erkenntnissen oder Problemen.
Aber Punkte sind für alle da! Der deutsche Mathematiker Oskar Perron schrieb: „Ein Punkt ist genau das, was der intelligente, aber harmlose, unverbildete Leser sich darunter vorstellt.“ So wollen wir es halten: Das vorliegende Heft will spannende Anknüpfungspunkte bieten, Standpunkte analysieren und punktgenau erklären.
So folgen wir etwa einem Physiker zur Sonne, in den Mittelpunkt unseres Sonnensystems, um zu ergründen, wie Sonneneruptionen entstehen. Mit einem Juristen diskutierten wir über Streitpunkte zwischen Recht und Religion, während Religionswissenschaftler in einem Reisetagebuch von einzigartigen Berührungspunkten mit der (Wissenschafts-)Kultur im Iran berichten. Kognitionsund Literaturwissenschaftler eröffnen gemeinsam besondere Blickpunkte – nämlich, wie wir Comics lesen und verstehen – und Wirtschaftsinformatiker zeigen Ansatzpunkte, mit denen sie Mensch und Maschine gemeinsam fit machen für Fabriken im Zeitalter von Industrie 4.0. Bildungswissenschaftler wiederum erläutern ihr Konzept dafür, wie das kreative Potenzial von Künstlern zum Ausgangspunkt werden kann, um Schülern einen individuellen Zugang zu Kunst zu ermöglichen. Psychologen offenbaren, warum die Farbe Rot uns zu Anziehungspunkten macht, während Geowissenschaftler erklären, warum ein Klimaphänomen namens El Niño weltweit – nasse und trockene – Brennpunkte verursacht. Und das sind nur einige Punkte von vielen …
Mit all dem hoffen wir natürlich, auch bei Ihnen zu punkten. Wir wünschen Ihnen eine anregende Lektüre! Punkt. Aus. Ende. Nein, Anfang!
Die Redaktion
Portal = Klima im Wandel
(2016)
We examined the spontaneous association between numbers and space by documenting attention deployment and the time course of associated spatial-numerical mapping with and without overt oculomotor responses. In Experiment 1, participants maintained central fixation while listening to number names. In Experiment 2, they made horizontal target-direct saccades following auditory number presentation. In both experiments, we continuously measured spontaneous ocular drift in horizontal space during and after number presentation. Experiment 2 also measured visual-probe-directed saccades following number presentation. Reliable ocular drift congruent with a horizontal mental number line emerged during and after number presentation in both experiments. Our results provide new evidence for the implicit and automatic nature of the oculomotor resonance effect associated with the horizontal spatial-numerical mapping mechanism.
Linked linear mixed models
(2016)
The complexity of eye-movement control during reading allows measurement of many dependent variables, the most prominent ones being fixation durations and their locations in words. In current practice, either variable may serve as dependent variable or covariate for the other in linear mixed models (LMMs) featuring also psycholinguistic covariates of word recognition and sentence comprehension. Rather than analyzing fixation location and duration with separate LMMs, we propose linking the two according to their sequential dependency. Specifically, we include predicted fixation location (estimated in the first LMM from psycholinguistic covariates) and its associated residual fixation location as covariates in the second, fixation-duration LMM. This linked LMM affords a distinction between direct and indirect effects (mediated through fixation location) of psycholinguistic covariates on fixation durations. Results confirm the robustness of distributed processing in the perceptual span. They also offer a resolution of the paradox of the inverted optimal viewing position (IOVP) effect (i.e., longer fixation durations in the center than at the beginning and end of words) although the opposite (i.e., an OVP effect) is predicted from default assumptions of psycholinguistic processing efficiency: The IOVP effect in fixation durations is due to the residual fixation-location covariate, presumably driven primarily by saccadic error, and the OVP effect (at least the left part of it) is uncovered with the predicted fixation-location covariate, capturing the indirect effects of psycholinguistic covariates. We expect that linked LMMs will be useful for the analysis of other dynamically related multiple outcomes, a conundrum of most psychonomic research.
Die Projektierung und Abwicklung sowie die statische und dynamische Analyse von Geschäftsprozessen im Bereich des Verwaltens und Regierens auf kommunaler, Länder- wie auch Bundesebene mit Hilfe von Informations- und Kommunikationstechniken beschäftigen Politiker und Strategen für Informationstechnologie ebenso wie die Öffentlichkeit seit Langem.
Der hieraus entstandene Begriff E-Government wurde in der Folge aus den unterschiedlichsten technischen, politischen und semantischen Blickrichtungen beleuchtet.
Die vorliegende Arbeit konzentriert sich dabei auf zwei Schwerpunktthemen:
• Das erste Schwerpunktthema behandelt den Entwurf eines hierarchischen Architekturmodells, für welches sieben hierarchische Schichten identifiziert werden können. Diese erscheinen notwendig, aber auch hinreichend, um den allgemeinen Fall zu beschreiben.
Den Hintergrund hierfür liefert die langjährige Prozess- und Verwaltungserfahrung als Leiter der EDV-Abteilung der Stadtverwaltung Landshut, eine kreisfreie Stadt mit rund 69.000 Einwohnern im Nordosten von München. Sie steht als Repräsentant für viele Verwaltungsvorgänge in der Bundesrepublik Deutschland und ist dennoch als Analyseobjekt in der Gesamtkomplexität und Prozessquantität überschaubar.
Somit können aus der Analyse sämtlicher Kernabläufe statische und dynamische Strukturen extrahiert und abstrakt modelliert werden.
Die Schwerpunkte liegen in der Darstellung der vorhandenen Bedienabläufe in einer Kommune. Die Transformation der Bedienanforderung in einem hierarchischen System, die Darstellung der Kontroll- und der Operationszustände in allen Schichten wie auch die Strategie der Fehlererkennung und Fehlerbehebung schaffen eine transparente Basis für umfassende Restrukturierungen und Optimierungen.
Für die Modellierung wurde FMC-eCS eingesetzt, eine am Hasso-Plattner-Institut für Softwaresystemtechnik GmbH (HPI) im Fachgebiet Kommunikationssysteme entwickelte Methodik zur Modellierung zustandsdiskreter Systeme unter Berücksichtigung möglicher Inkonsistenzen (Betreuer: Prof. Dr.-Ing. Werner Zorn [ZW07a, ZW07b]).
• Das zweite Schwerpunktthema widmet sich der quantitativen Modellierung und Optimierung von E-Government-Bediensystemen, welche am Beispiel des Bürgerbüros der Stadt Landshut im Zeitraum 2008 bis 2015 durchgeführt wurden. Dies erfolgt auf Basis einer kontinuierlichen Betriebsdatenerfassung mit aufwendiger Vorverarbeitung zur Extrahierung mathematisch beschreibbarer Wahrscheinlichkeitsverteilungen.
Der hieraus entwickelte Dienstplan wurde hinsichtlich der erzielbaren Optimierungen im dauerhaften Echteinsatz verifiziert.
[ZW07a] Zorn, Werner: «FMC-QE A New Approach in Quantitative Modeling», Vortrag anlässlich: MSV'07- The 2007 International Conference on Modeling, Simulation and Visualization Methods WorldComp2007, Las Vegas, 28.6.2007.
[ZW07b] Zorn, Werner: «FMC-QE, A New Approach in Quantitative Modeling», Veröffentlichung, Hasso-Plattner-Institut für Softwaresystemtechnik an der Universität Potsdam, 28.6.2007.
Discourse production is crucial for communicative success and is in the core of aphasia assessment and treatment. Coherence differentiates discourse from a series of utterances/sentences; it is internal unity and connectedness, and, as such, perhaps the most inherent property of discourse. It is unclear whether people with aphasia, who experience various language production difficulties, preserve the ability to produce coherent discourse. A more general question of how coherence is established and represented linguistically has been addressed in the literature, yet remains unanswered. This dissertation presents an investigation of discourse production in aphasia and the linguistic mechanisms of establishing coherence.
Hantaviruses are zoonotic viruses transmitted to humans by persistently infected rodents, giving rise to serious outbreaks of hemorrhagic fever with renal syndrome (HFRS) or of hantavirus pulmonary syndrome (HPS), depending on the virus, which are associated with high case fatality rates. There is only limited knowledge about the organization of the viral particles and in particular, about the hantavirus membrane fusion glycoprotein Gc, the function of which is essential for virus entry. We describe here the X-ray structures of Gc from Hantaan virus, the type species hantavirus and responsible for HFRS, both in its neutral pH, monomeric pre-fusion conformation, and in its acidic pH, trimeric post-fusion form. The structures confirm the prediction that Gc is a class II fusion protein, containing the characteristic beta-sheet rich domains termed I, II and III as initially identified in the fusion proteins of arboviruses such as alpha-and flaviviruses. The structures also show a number of features of Gc that are distinct from arbovirus class II proteins. In particular, hantavirus Gc inserts residues from three different loops into the target membrane to drive fusion, as confirmed functionally by structure-guided mutagenesis on the HPS-inducing Andes virus, instead of having a single "fusion loop". We further show that the membrane interacting region of Gc becomes structured only at acidic pH via a set of polar and electrostatic interactions. Furthermore, the structure reveals that hantavirus Gc has an additional N-terminal "tail" that is crucial in stabilizing the post-fusion trimer, accompanying the swapping of domain III in the quaternary arrangement of the trimer as compared to the standard class II fusion proteins. The mechanistic understandings derived from these data are likely to provide a unique handle for devising treatments against these human pathogens.
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.
The role that climate and environmental history may have played in influencing human evolution has been the focus of considerable interest and controversy among paleoanthropologists for decades. Prior attempts to understand the environmental history side of this equation have centered around the study of outcrop sediments and fossils adjacent to where fossil hominins (ancestors or close relatives of modern humans) are found, or from the study of deep sea drill cores. However, outcrop sediments are often highly weathered and thus are unsuitable for some types of paleoclimatic records, and deep sea core records come from long distances away from the actual fossil and stone tool remains. The Hominin Sites and Paleolakes Drilling Project (HSPDP) was developed to address these issues. The project has focused its efforts on the eastern African Rift Valley, where much of the evidence for early hominins has been recovered. We have collected about 2 km of sediment drill core from six basins in Kenya and Ethiopia, in lake deposits immediately adjacent to important fossil hominin and archaeological sites. Collectively these cores cover in time many of the key transitions and critical intervals in human evolutionary history over the last 4 Ma, such as the earliest stone tools, the origin of our own genus Homo, and the earliest anatomically modern Homo sapiens. Here we document the initial field, physical property, and core description results of the 2012-2014 HSPDP coring campaign.
Preface
(2016)