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Stress drop is a key factor in earthquake mechanics and engineering seismology. However, stress drop calculations based on fault slip can be significantly biased, particularly due to subjectively determined smoothing conditions in the traditional least-square slip inversion. In this study, we introduce a mechanically constrained Bayesian approach to simultaneously invert for fault slip and stress drop based on geodetic measurements. A Gaussian distribution for stress drop is implemented in the inversion as a prior. We have done several synthetic tests to evaluate the stability and reliability of the inversion approach, considering different fault discretization, fault geometries, utilized datasets, and variability of the slip direction, respectively. We finally apply the approach to the 2010 M8.8 Maule earthquake and invert for the coseismic slip and stress drop simultaneously. Two fault geometries from the literature are tested. Our results indicate that the derived slip models based on both fault geometries are similar, showing major slip north of the hypocenter and relatively weak slip in the south, as indicated in the slip models of other studies. The derived mean stress drop is 5-6 MPa, which is close to the stress drop of similar to 7 MPa that was independently determined according to force balance in this region Luttrell et al. (J Geophys Res, 2011). These findings indicate that stress drop values can be consistently extracted from geodetic data.
In a recent paper, the Lefschetz number for endomorphisms (modulo trace class operators) of sequences of trace class curvature was introduced. We show that this is a well defined, canonical extension of the classical Lefschetz number and establish the homotopy invariance of this number. Moreover, we apply the results to show that the Lefschetz fixed point formula holds for geometric quasiendomorphisms of elliptic quasicomplexes.
This reference paper describes the sampling and contents of the IZA Evaluation Dataset Survey and outlines its vast potential for research in labor economics. The data have been part of a unique IZA project to connect administrative data from the German Federal Employment Agency with innovative survey data to study the out-mobility of individuals to work. This study makes the survey available to the research community as a Scientific Use File by explaining the development, structure, and access to the data. Furthermore, it also summarizes previous findings with the survey data.
Fluid intelligence (fluid IQ), defined as the capacity for rapid problem solving and behavioral adaptation, is known to be modulated by learning and experience. Both stressful life events (SLES) and neural correlates of learning [specifically, a key mediator of adaptive learning in the brain, namely the ventral striatal representation of prediction errors (PE)] have been shown to be associated with individual differences in fluid IQ. Here, we examine the interaction between adaptive learning signals (using a well-characterized probabilistic reversal learning task in combination with fMRI) and SLES on fluid IQ measures. We find that the correlation between ventral striatal BOLD PE and fluid IQ, which we have previously reported, is quantitatively modulated by the amount of reported SLES. Thus, after experiencing adversity, basic neuronal learning signatures appear to align more closely with a general measure of flexible learning (fluid IQ), a finding complementing studies on the effects of acute stress on learning. The results suggest that an understanding of the neurobiological correlates of trait variables like fluid IQ needs to take socioemotional influences such as chronic stress into account.
The Arabidopsis Kinome
(2014)
Background
Protein kinases constitute a particularly large protein family in Arabidopsis with important functions in cellular signal transduction networks. At the same time Arabidopsis is a model plant with high frequencies of gene duplications. Here, we have conducted a systematic analysis of the Arabidopsis kinase complement, the kinome, with particular focus on gene duplication events. We matched Arabidopsis proteins to a Hidden-Markov Model of eukaryotic kinases and computed a phylogeny of 942 Arabidopsis protein kinase domains and mapped their origin by gene duplication.
Results
The phylogeny showed two major clades of receptor kinases and soluble kinases, each of which was divided into functional subclades. Based on this phylogeny, association of yet uncharacterized kinases to families was possible which extended functional annotation of unknowns. Classification of gene duplications within these protein kinases revealed that representatives of cytosolic subfamilies showed a tendency to maintain segmentally duplicated genes, while some subfamilies of the receptor kinases were enriched for tandem duplicates. Although functional diversification is observed throughout most subfamilies, some instances of functional conservation among genes transposed from the same ancestor were observed. In general, a significant enrichment of essential genes was found among genes encoding for protein kinases.
Conclusions
The inferred phylogeny allowed classification and annotation of yet uncharacterized kinases. The prediction and analysis of syntenic blocks and duplication events within gene families of interest can be used to link functional biology to insights from an evolutionary viewpoint. The approach undertaken here can be applied to any gene family in any organism with an annotated genome.
Background
In the past, plyometric training (PT) has been predominantly performed on stable surfaces. The purpose of this pilot study was to examine effects of a 7-week lower body PT on stable vs. unstable surfaces. This type of exercise condition may be denoted as metastable equilibrium.
Methods
Thirty-three physically active male sport science students (age: 24.1 ± 3.8 years) were randomly assigned to a PT group (n = 13) exercising on stable (STAB) and a PT group (n = 20) on unstable surfaces (INST). Both groups trained countermovement jumps, drop jumps, and practiced a hurdle jump course. In addition, high bar squats were performed. Physical fitness tests on stable surfaces (hexagonal obstacle test, countermovement jump, hurdle drop jump, left-right hop, dynamic and static balance tests, and leg extension strength) were used to examine the training effects.
Results
Significant main effects of time (ANOVA) were found for the countermovement jump, hurdle drop jump, hexagonal test, dynamic balance, and leg extension strength. A significant interaction of time and training mode was detected for the countermovement jump in favor of the INST group. No significant improvements were evident for either group in the left-right hop and in the static balance test.
Conclusions
These results show that lower body PT on unstable surfaces is a safe and efficient way to improve physical performance on stable surfaces.
Portal alumni
(2014)
Die Beliebtheit von Medienberufen ist ungebrochen. Das zeigt sich unter anderem an der Zahl der Studieninteressierten. So haben sich allein in diesem Jahr mehr als 1 500 junge Leute auf einen der 44 Plätze für den Studiengang Medienwissenschaft an der Universität Potsdam beworben. Nach ihrem erfolgreichen Abschluss allerdings konkurrieren die Absolventen am Arbeitsmarkt mit Tausenden Abgängern anderer Hochschulen aus Film-, Medien- und Kommunikationsstudiengängen. Das sind allein in der Region Berlin-Brandenburg jährlich etwa 1 500. Doch nach jahrzehntelangem Boom der Medienbranche hat sich der Arbeitsmarkt im vergangenen Jahrzehnt drastisch verändert. Konjunkturkrise, Kursrückgänge und rückläufige Werbeinvestitionen schwächten die Medien deutlich. Es folgten daraus schlechte Gewinnergebnisse, Einsparungen und Personalreduzierung, insbesondere bei den Printmedien. Die Insolvenz der Frankfurter Rundschau oder die Einstellung der Financial Times Deutschland sind nur zwei eklatante Beispiele. Auf der anderen Seite boomt der dynamische Online-Markt aufgrund des veränderten Nutzerverhaltens insbesondere der jungen Generation, die ihre Informationen zunehmend aus Internet, Apps und sozialen Netzwerken gewinnen. Die Berufsaussichten für all Jene, die „Irgendwas mit Medien“ studieren wollen sind zwar aufgrund des Arbeitsmarktes schwieriger geworden, sie sind aber dennoch vielfältig. Guter Journalismus wird weiterhin benötigt und auch Öffentlichkeitsarbeiter sind gefragt. Darüber hinaus stehen Absolventen der Kommunikationswissenschaften die Türen in die Medienplanung oder in der Markt- und Meinungsforschung offen. Und nicht zuletzt sind Experten in der Online-Branche gefragt. Portal alumni hat sich in diesem Jahr dafür interessiert, welche Karrierewege Absolventen der der Universität Potsdam in Medienberufen bisher gegangen sind. Dabei zeigt sich, dass auch hier die Wege selten linear verlaufen und berufliche Erfolge sich keineswegs leicht einstellten.
The B fields in OB stars (BOB) survey is an ESO large programme collecting spectropolarimetric observations for a large number of early-type stars in order to study the occurrence rate, properties, and ultimately the origin of magnetic fields in massive stars. As of July 2014, a total of 98 objects were observed over 20 nights with FORS2 and HARPSpol. Our preliminary results indicate that the fraction of magnetic OB stars with an organised, detectable field is low. This conclusion, now independently reached by two different surveys, has profound implications for any theoretical model attempting to explain the field formation in these objects. We discuss in this contribution some important issues addressed by our observations (e.g., the lower bound of the field strength) and the discovery of some remarkable objects.
Nested application conditions generalise the well-known negative application conditions and are important for several application domains. In this paper, we present Local Church-Rosser, Parallelism, Concurrency and Amalgamation Theorems for rules with nested application conditions in the framework of M-adhesive categories, where M-adhesive categories are slightly more general than weak adhesive high-level replacement categories. Most of the proofs are based on the corresponding statements for rules without application conditions and two shift lemmas stating that nested application conditions can be shifted over morphisms and rules.
An der BTU finden freiwillige Kurse zur Studienvorbereitung, im Rahmen des BMBF geförderten Projektes „Blended Learning Anfangshürden erkennen zur Unterstützung der fachspezifischen Studienvorbereitung und des Lernerfolges im ersten Studienjahr“, statt. Die Kluft zwischen notwendigen und tatsächlich vorhandenen Fähigkeiten ist in der Mathematik bei vielen angehenden Studierenden groß und die zur Verfügung stehende Zeit oft zu gering. Hier setzt dieses Konzept an. Neben Präsenzveranstaltungen enthält der Kurs unterstützte Selbstlernphasen. Diese werden durch einen virtuellen Kursraum und einer Anwendung für mobile Endgeräte (App) unterstützt.
Im Rahmen eines interdisziplinären studentischen Projekts wurde ein Framework für mobile pervasive Lernspiele entwickelt. Am Beispiel des historischen Lernortes Park Sanssouci wurde auf dieser Grundlage ein Lernspiel für Schülerinnen und Schüler implementiert. Die geplante Evaluation soll die Lernwirksamkeit von geobasierten mobilen Lernspielen messen. Dazu wird die Intensität des Flow-Erlebens mit einer ortsgebundenen alternativen Umsetzung verglichen.
Das gesteckte Ziel unserer Applikation ist es nicht nur die ständige Verfügbarkeit von Lernmaterialien zu ermöglichen, sondern auch die gesamte Kommunikation zwischen Dozenten und Studierenden, sowie Studierende unter sich, zu verändern. Eine Mischung aus E-Learning, Blended-Learning und Mobile- Learning soll es hier allen Teilnehmer ermöglichen, ortsungebunden zu agieren. Neue Funktionen sollen es den Studierenden ermöglichen, besser miteinander zu arbeiten, zu kooperieren und neue Bekanntschaften zu schließen.
Der vorliegende Beitrag befasst sich mit der Konstruktion eines Lehr-/ Lernszenarios polyvalenter Grundlagenvorlesungen in naturwissenschaftlichen Fachwissenschaften. Das Szenario verbindet klassische Vorlesungen mit virtuellen Elementen wie Online-Kursen, Online-Foren und Audience-Response-Systemen sowie dem Arbeiten in Kleingruppen mit Ansätzen des problemorientierten Lernens. Ziel ist es das Grundlagenwissen der Studierenden anzupassen, das Arbeiten in Gruppen zu fördern und problemorientiertes Lernen zu erlernen.
Das Projekt „Medienbildung in der LehrerInnenbildung“ hat das Ziel, den Einsatz digitaler Medien in den Lehramtsstudiengängen der Universität Potsdam nachhaltig zu fördern. Am Beispiel der Musiklehrerausbildung (Lehrstuhl für Musikpädagogik und Musikdidaktik) wurde ein Konzept für die Nutzung von Video-Podcasts in schulischen Praxisphasen entwickelt, um Studierende bei der Unterrichtsplanung zu unterstützen. Die fachspezifische Umsetzung des E-Learning-Ansatzes und die damit verbundenen Möglichkeiten und Heraus- forderungen werden gezeigt und betonen die Wichtigkeit der Zusammenarbeit zwischen Fachdidaktik und Mediendidaktik, um eine bedarfsorientierte Lösung zu finden, die praktisch umsetzbar ist.
Bewegunglesen.com
(2014)
bewegunglesen.com (mit Silber bei den Best of Swiss Web Awards 2013 ausgezeichnet) ist ein E-Learning-Tool und bietet für Sportunterrichtende und Studierende eine webbasierte, interaktive Übungsgelegenheit, die Bewegungsanalyse und das kriteriengeleitete Verbessern von Fertigkeiten zu erlernen. Bewegungsabläufe mit ihren Kernbewegungen werden praxisnah und schulstufengerecht vermittelt. Daneben können auch Unterrichtsvideos hochgeladen, geschnitten, durch Grafiken und Fakten angereichert und innerhalb der Community geteilt werden. Aus den Clips lassen sich Übungen und Prüfungen mit Beurteilungskriterien des Bewegungsablaufs zusammenstellen, welche automatisiert ausgewertet werden.
Recently, interest in collecting and mining large sets of educational data on student background and performance to conduct research on learning and instruction has developed as an area generally referred to as learning analytics. Higher education leaders are recognising the value of learning analytics for improving not only learning and teaching but also the entire educational arena. However, theoretical concepts and empirical evidence need to be generated within the fast evolving field of learning analytics. In this paper, we introduce a holistic learning analytics framework. Based on this framework, student, learning, and curriculum profiles have been developed which include relevant static and dynamic parameters for facilitating the learning analytics framework. Based on the theoretical model, an empirical study was conducted to empirically validate the parameters included in the student profile. The paper concludes with practical implications and issues for future research.
Portal Wissen = Time
(2014)
“What then is time?”, Augustine of Hippo sighs melancholically in Book XI of “Confessions” and continues, “If no one asks me, I know; if I want to explain it to a questioner, I don’t know.” Even today, 1584 years after Augustine, time still appears mysterious. Treatises about the essence of time fill whole libraries – and this magazine.
However, questions of essence are alien to modern sciences. Time is – at least in physics – unproblematic: “Time is defined so that motion looks simple”, briefly and prosaically phrased, waves goodbye to Augustine’s riddle and to the Newtonian concept of absolute time, whose mathematical flow can only be approximately recorded with earthly instruments anyway.
In our everyday language and even in science we still speak of the flow of time but time has not been a natural condition for quite a while now. It is rather a conventional order parameter for change and movement. Processes are arranged by using a class of processes as a counting system in order to compare other processes and to organize them with the help of the temporary categories “before”, “during”, and “after”.
During Galileo’s time one’s own pulse was seen as the time standard for the flight of cannon balls. More sophisticated examination methods later made this seem too impractical. The distance-time diagrams of free-flying cannon balls turned out to be rather imprecise, difficult to replicate, and in no way “simple”. Nowadays, we use cesium atoms. A process is said to take one second when a caesium-133 atom completes 9,192,631,770 periods of the radiation corresponding to the transition between two hyperfine levels of the ground state. A meter is the length of the path travelled by light in a vacuum in exactly 1/299,792,458 of a second. Fortunately, these data are hard-coded in the Global Positioning System GPS so users do not have to reenter them each time they want to know where they are. In the future, however, they might have to download an app because the time standard has been replaced by sophisticated transitions to ytterbium.
The conventional character of the time concept should not tempt us to believe that everything is somehow relative and, as a result, arbitrary. The relation of one’s own pulse to an atomic clock is absolute and as real as the relation of an hourglass to the path of the sun. The exact sciences are relational sciences. They are not about the thing-initself as Newton and Kant dreamt, but rather about relations as Leibniz and, later, Mach pointed out.
It is not surprising that the physical time standard turned out to be rather impractical for other scientists. The psychology of time perception tells us – and you will all agree – that the perceived age is quite different from the physical age. The older we get the shorter the years seem. If we simply assume that perceived duration is inversely related to physical age and that a 20-year old also perceives a physical year as a psychological one, we come to the surprising discovery that at 90 years we are 90 years old. With an assumed life expectancy of 90 years, 67% (or 82%) of your felt lifetime is behind you at the age of 20 (or 40) physical years.
Before we start to wallow in melancholy in the face of the “relativity of time”, let me again quote Augustine. “But at any rate this much I dare affirm I know: that if nothing passed there would be no past time; if nothing were approaching, there would be no future time; if nothing were, there would be no present time.” Well, – or as Bob Dylan sings “The times they are a-changin”.
I wish you an exciting time reading this issue.
Prof. Martin Wilkens
Professor of Quantum Optics
Portal Wissen = Believe
(2014)
People want to know what is real. Children enjoy listening to a story but when my children were about four years old they started asking whether the story really happened or was just invented. Likewise, only on a higher level, our academic curiosity is fuelled by our interest in knowing what is real. When we analyze poetic texts or dreams we are trying to distinguish between the facts (e.g. neurological ones or linguistic structures) and merely assumed influences. Ideally we can present results that were logically understood by others and that we can repeat empirically. But in most cases this is not possible. We cannot read every book and cannot look through every microscope, not even within our own discipline. In the world we live in we depend on trusting the information of others, like how to get to the train station or what the weather is like in Ulaanbataar. This is why we are used to believing others, our friends or the news anchors. This is not a childish behavior but a necessity. Of course, it is risky because they could all be lying to us, like in a Truman Show situation. The only time we are able to know that we are in reality is when we transcend our selfconsciousness and when we accept two propositions: first, that we are not only objects but also subjects in the consciousness of others and second that our dialogic relations are again observed by a third party that is not part of this intersubjective world.
For religious people this is “belief” - belief as the assumption that all human relations only become real, serious and beyond any doubt if they know they are under the eyes of God. Only before Him something is in itself and not only “for me” or “among us”. That is why biblical language distinguishes between three forms of belief: the relationship with the world of things (“to believe that”), the relationship to the world of subjects (“to believe somebody”) and the assumption of a subjective supernatural reality (“to believe in” or “faith”). From an academic point of view belief is a holistic hypothesis. Belief is not the opposite of knowledge but it is the attempt to save reality from doubt by comprehending the fragile empirical world as an expression of a stable transcendent world.
When I talk to students they often ask not only about what I know but what I believe. As a professor for Religious Studies and a believing Catholic I am caught in the middle. On the one hand, it is my duty as a professor to doubt everything, i.e. to attribute each religious text to its historical context and sociological functions. On the other hand, I, as a Christian, consider certain religious documents, in my case the Bible, an interpretable but nevertheless irreversible, revealed text about the origin of reality. On weekdays the New Testament is a collection of ancient writings among many others, on Sundays it is the revelation. You can make a clear distinction between these two perspectives but it is difficult to decide whether doubt or belief is more real.
This issue of “Portal Wissen” explores this dual relationship of belief. What is the attitude of science towards belief – is it a religious one? Where does science bring things to light that we can hardly believe or that make us believe (again)? What happens if research clears up erroneous assumptions or myths? Is science able to investigate things that are convincing but inexplicable? How can it maintain its credibility and develop even so?
These questions appear again and again in the contributions of this “Portal Wissen”. They form a manifold, exciting and surprising picture of the research projects and academics at the University of Potsdam. Believe me, it will be an enjoyable read.
Prof. Johann Hafner
Professor of Religious Studies with Focus on Christianity Dean of the Faculty of Arts
Portal Wissen = Zeit
(2014)
„Was ist also 'Zeit'?“ seufzt Augustinus von Hippo im 11. Buch seiner „Confessiones“ melancholisch, und fährt fort „Wenn mich niemand danach fragt, weiß ich es; will ich einem Fragenden es erklären, weiß ich es nicht.“ Auch heute, 1584 Jahre nach Augustinus, erscheint 'Zeit' immer noch rätselhaft. Abhandlungen über das Wesen der Zeit füllen Bibliotheken. Oder eben dieses Heft.
Wesensfragen sind den modernen Wissenschaften allerdings fremd. Zeit ist – zumindest in der Physik – unproblematisch. „Time is defined so that Motion looks simple“ erkärt man kurz und trocken, und verabschiedet sich damit vom Augustinischen Rätsel oder der Newtonschen Vorstellung einer absoluten Zeit, deren mathematischen Fluss man durch irdische Instrumente eh immer nur näherungsweise erfassen kann.
In der Alltagssprache, selbst in den Wissenschaften, reden wir zwar weiterhin vom Fluss der Zeit, aber Zeit ist schon lange keine natürliche Gegebenheit mehr. Zeit ist vielmehr ein konventioneller Ordnungsparameter für Änderung und Bewegung. Geordnet werden Prozesse, indem eine Klasse von Prozessen als Zählsystem dient, um andere Prozesse mit ihnen zu vergleichen und anhand der temporären Kategorien „vorher“, „während“ und „nachher“ anzuordnen.
Zu Galileis Zeiten galt der eigene Pulsschlag als Zeitstandard für den Flug von Kanonenkugeln. Mit zunehmender Verfeinerung der Untersuchungsmethoden erschien das zu unpraktisch: Die Weg-Zeit-Diagramme frei fliegender Kanonenkugeln erweisen sich in diesem Standard ziemlich verwackelt, schlecht reproduzierbar, und keineswegs „simpel“. Heutzutage greift man zu Cäsium-Atomen. Demnach dauert ein Prozess eine Sekunde, wenn ein 133Cs-Atom genau 9 192 631 770 Schwingungen zwischen zwei sogenannten Hyperfeinzuständen des Grundzustands vollführt hat. Und ein Meter ist die Entfernung, die Licht im Vakuum in exakt 1/299 792 458 Sekunden zurücklegt. Glücklicherweise sind diese Daten im General Positioning System GPS hart kodiert, so dass der Nutzer sie nicht jedes Mal aufs Neue eingeben muss, wenn er wissen will, wo er ist. Aber schon morgen muss er sich vielleicht ein Applet runterladen, weil der Zeitstandard durch raffinierte Übergänge in Ytterbium ersetzt wurde.
Der konventionelle Charakter des Zeitbegriffs sollte nicht dazu verführen zu glauben, alles sei irgendwie relativ und daher willkürlich. Die Beziehung eines Pulsschlags zu einer Atomuhr ist absolut, und genauso real, wie die Beziehung einer Sanduhr zum Lauf der Sonne. Die exakten Wissenschaften sind Beziehungswissenschaften. Sie handeln nicht vom Ding an sich, was Newton und Kant noch geträumt haben, sondern von Beziehungen – worauf schon Leibniz und später Mach hingewiesen haben.
Kein Wunder, dass sich für andere Wissenschaften der physikalische Zeit-Standard als ziemlich unpraktisch erweist. Der Psychologie der Zeitwahrnehmung entnehmen wir – und jeder wird das bestätigen können – dass das gefühlte Alter durchaus verschieden ist vom physikalischen Alter. Je älter man ist, desto kürzer erscheinen einem die Jahre.
Unter der einfachen Annahme, dass die gefühlte Dauer umgekehrt proportional zum physikalischen Alter ist, und man als Zwanzigjähriger ein physikalisches Jahr auch psychologisch als ein Jahr empfindet, ergibt sich der erstaunliche Befund, dass man mit 90 Jahren 90 Jahre ist. Und – bei einer angenommenen Lebenserwartung von 90 Jahren – mit 20 (bzw. 40) physikalischen Jahren bereits 67 (bzw. 82) Prozent seiner gefühlten Lebenszeit hinter sich hat.
Bevor man angesichts der „Relativität von Zeit“ selbst in Melancholie versinkt, vielleicht die Fortsetzung des Eingangszitats von Augustinus: „Aber zuversichtlich behaupte ich zu wissen, dass es vergangene Zeit nicht gäbe, wenn nichts verginge, und nicht künftige Zeit, wenn nichts herankäme, und nicht gegenwärtige Zeit wenn nichts seiend wäre.“ Tja – oder mit Bob Dylan „The times they're a changing“.
Ich wünsche Ihnen eine spannende Zeit bei der Lektüre dieser Ausgabe.
Prof. Dr. Martin Wilkens
Professor für Quantenoptik
Portal Wissen = Glauben
(2014)
Menschen wollen wissen, was wirklich ist. Kinder lassen sich gern eine Geschichte erzählen, aber spätestens mit vier Jahren fragten meine, ob diese Geschichte so passiert sei oder nur erfunden. Das setzt sich fort: Auch unsere wissenschaftliche Neugier wird vom Interesse befeuert herauszufinden, was wirklich ist. Selbst dort, wo wir poetische Texte oder Träume erforschen, tun wir es in der Absicht, die realen sprachlichen Strukturen bzw. die neurologischen Faktoren von bloß vermuteten zu unterscheiden. Im Idealfall können wir Ergebnisse präsentieren, die von anderen logisch nachvollzogen und empirisch wiederholbar sind. Meistens geht das aber nicht. Wir können nicht jedes Buch lesen und nicht in jedes Mikroskop schauen, nicht einmal innerhalb der eigenen Disziplin. Wie viel mehr sind wir in der Lebenswelt darauf angewiesen, den Ausführungen anderer zu vertrauen, wenn wir wissen wollen, wo es zum Bahnhof geht oder ob es in Ulan Bator schön ist. Deshalb haben wir uns daran gewöhnt, anderen Glauben zu schenken, vom Freund bis zum Tagesschausprecher. Das ist kein kindliches Verhalten, sondern eine Notwendigkeit. Freilich ist das riskant, denn alle anderen könnten uns – wie in der „Truman- Show“ – anlügen. In der Wirklichkeit wissen wir uns erst dann, wenn wir unser Selbstbewusstsein verlassen und akzeptieren, dass wir erstens nicht nur Objekte, sondern Subjekte im Bewusstsein von anderen sind, und zweitens, dass alle unsere dialogischen Beziehungen noch einmal von einem Dritten betrachtet werden, der nicht Teil dieser Welt ist.
Für Religiöse ist das der Glaube. Glaube als Unterstellung, dass alle menschlichen Beziehungen erst dann wirklich, ernst und über Zweifel erhaben sind, wenn sie sich vor den Augen Gottes wissen. Erst vor ihm ist etwas als es selbst und nicht nur „für mich“ oder „unter uns“. Daher unterscheidet die biblische Sprache drei Formen des Glaubens: die Beziehung zur Ding-Welt („glauben, dass“), die Beziehung zur Subjekt-Welt („jemandem glauben“) und die Annahme einer subjekthaften überirdischen Wirklichkeit („glauben an“). Wissenschaftstheoretisch gesehen ist Glaube also eine Totalhypothese. Glaube ist nicht das Gegenteil von Wissen, sondern der Versuch, Wirklichkeit vor dem Zweifel zu retten, indem man die fragile empirische Welt als Ausdruck einer stabilen transzendenten Welt begreift.
Oft wollen Studierende in Gesprächen nicht nur wissen, was ich weiß, sondern, was ich glaube. Als Religionswissenschaftler und gleichzeitig gläubiger Katholik sitze ich zwischen den Stühlen: Einerseits ist es als Professor meine Aufgabe, alles zu bezweifeln, d.h. jeden religiösen Text auf seine historischen Kontexte und soziologischen Funktionen zurückzuführen. Andererseits hält der Christ in mir bestimmte religiöse Dokumente – in meinem Fall die Bibel – zwar für einen interpretierbaren, aber doch irreversiblen, offenbarten Text, der vom Ursprung der Wirklichkeit handelt. Werktags ist das Neue Testament eine antike Schriftensammlung neben vielen anderen, am Sonntag ist es die Offenbarung. Beides kann klar unterschieden werden, aber es ist schwer zu entscheiden, ob das Zweifeln oder das Glauben wirklicher ist.
Das vorliegende Heft geht diesem doppelten Verhältnis zum Glauben nach: Wie steht Wissenschaft zum Glauben – ob religiös oder nicht? Wo bringt Wissenschaft Dinge ans Licht, die wir kaum glauben mögen oder uns (wieder) glauben lassen? Was passiert, wenn Forschung irrige Annahmen oder Mythen aufklärt? Ist Wissenschaft in der Lage, Dingen auf den Grund zu gehen, die zwar überzeugend, aber unerklärbar sind? Wie kann sie selbst glaubwürdig bleiben und sich dennoch weiterentwickeln?
In den Beiträgen dieser „Portal Wissen“ scheinen diese Fragen immer wieder auf. Sie bilden ein vielfältiges, spannendes und auch überraschendes Bild der Forschungsprojekte und der Wissenschaftler an der Universität Potsdam. Glauben Sie mir, es erwartet Sie eine anregende Lektüre!
Prof. Dr. Johann Hafner
Professor für Religionswissenschaft mit dem Schwerpunkt Christentum
Dekan der Philosophischen Fakultät
Unterschiedliche Verfahren zur Ermittlung von Georadar-Wellengeschwindigkeiten wurden entwickelt und erfolgreich angewendet. Für die Verfahren wurden statistische Methoden und Schwarmintelligenz-Algorithmen benutzt. Es wurde gezeigt, dass die neuen Verfahren schneller, präziser und besser reproduzierbare Ergebnisse für Georadar-Wellengeschwindigkeit erzielen als herkömmliche Verfahren.
Mit verbesserten Werten der Georadar-Wellengeschwindigkeit lassen sich die verzerrten dreidimensionalen Abbilder der obersten zehn Meter des Untergrundes, welche sich mit Georadar-Daten erzeugen lassen, korrigieren. In diesen korrigierten Abbildern sind dann realistische Tiefen von Schichten oder Objekten im Untergrund besser messbar. Außerdem verbessern präzisere Wellengeschwindigkeiten die Bestimmung von Bodenparametern, wie Wassergehalt oder Tonanteil. Die präsentierten Verfahren erlauben eine quantitative Angabe von Fehlern der bestimmten Wellengeschwindigkeit und der daraus folgenden Tiefen und Bodenparametern im Untergrund. Die Vorteile dieser neu entwickelten Verfahren zur Charakterisierung des Untergrundes der oberen Meter wurde an Feldbeispielen demonstriert.
We report on the development of an on-chip RPA (recombinase polymerase amplification) with simultaneous multiplex isothermal amplification and detection on a solid surface. The isothermal RPA was applied to amplify specific target sequences from the pathogens Neisseria gonorrhoeae, Salmonella enterica and methicillin-resistant Staphylococcus aureus (MRSA) using genomic DNA. Additionally, a positive plasmid control was established as an internal control. The four targets were amplified simultaneously in a quadruplex reaction. The amplicon is labeled during on-chip RPA by reverse oligonucleotide primers coupled to a fluorophore. Both amplification and spatially resolved signal generation take place on immobilized forward primers bount to expoxy-silanized glass surfaces in a pump-driven hybridization chamber. The combination of microarray technology and sensitive isothermal nucleic acid amplification at 38 °C allows for a multiparameter analysis on a rather small area. The on-chip RPA was characterized in terms of reaction time, sensitivity and inhibitory conditions. A successful enzymatic reaction is completed in <20 min and results in detection limits of 10 colony-forming units for methicillin-resistant Staphylococcus aureus and Salmonella enterica and 100 colony-forming units for Neisseria gonorrhoeae. The results show this method to be useful with respect to point-of-care testing and to enable simplified and miniaturized nucleic acid-based diagnostics.
The Babylonian Talmud (BT) attributes the idea of committing a transgression for the sake of God to R. Nahman b. Isaac (RNBI). RNBI's statement appears in two parallel sugyot in the BT (Nazir 23a; Horayot 10a). Each sugya has four textual witnesses. By comparing these textual witnesses, this paper will attempt to reconstruct the sugya's earlier (or, what some might term, original) dialectical form, from which the two familiar versions of the text in Nazir and Horayot evolved. This article reveals the specific ways in which, value-laden conceptualizations have a major impact on the Talmud's formulation, as we know it today.
Ultraschall Berlin
(2014)
We propose a novel cluster-based reduced-order modelling (CROM) strategy for unsteady flows. CROM combines the cluster analysis pioneered in Gunzburger's group (Burkardt, Gunzburger & Lee, Comput. Meth. Appl. Mech. Engng, vol. 196, 2006a, pp. 337-355) and transition matrix models introduced in fluid dynamics in Eckhardt's group (Schneider, Eckhardt & Vollmer, Phys. Rev. E, vol. 75, 2007, art. 066313). CROM constitutes a potential alternative to POD models and generalises the Ulam-Galerkin method classically used in dynamical systems to determine a finite-rank approximation of the Perron-Frobenius operator. The proposed strategy processes a time-resolved sequence of flow snapshots in two steps. First, the snapshot data are clustered into a small number of representative states, called centroids, in the state space. These centroids partition the state space in complementary non-overlapping regions (centroidal Voronoi cells). Departing from the standard algorithm, the probabilities of the clusters are determined, and the states are sorted by analysis of the transition matrix. Second, the transitions between the states are dynamically modelled using a Markov process. Physical mechanisms are then distilled by a refined analysis of the Markov process, e. g. using finite-time Lyapunov exponent (FTLE) and entropic methods. This CROM framework is applied to the Lorenz attractor (as illustrative example), to velocity fields of the spatially evolving incompressible mixing layer and the three-dimensional turbulent wake of a bluff body. For these examples, CROM is shown to identify non-trivial quasi-attractors and transition processes in an unsupervised manner. CROM has numerous potential applications for the systematic identification of physical mechanisms of complex dynamics, for comparison of flow evolution models, for the identification of precursors to desirable and undesirable events, and for flow control applications exploiting nonlinear actuation dynamics.
claspfolio 2
(2014)
Building on the award-winning, portfolio-based ASP solver claspfolio, we present claspfolio 2, a modular and open solver architecture that integrates several different portfolio-based algorithm selection approaches and techniques. The claspfolio 2 solver framework supports various feature generators, solver selection approaches, solver portfolios, as well as solver-schedule-based pre-solving techniques. The default configuration of claspfolio 2 relies on a light-weight version of the ASP solver clasp to generate static and dynamic instance features. The flexible open design of claspfolio 2 is a distinguishing factor even beyond ASP. As such, it provides a unique framework for comparing and combining existing portfolio-based algorithm selection approaches and techniques in a single, unified framework. Taking advantage of this, we conducted an extensive experimental study to assess the impact of different feature sets, selection approaches and base solver portfolios. In addition to gaining substantial insights into the utility of the various approaches and techniques, we identified a default configuration of claspfolio 2 that achieves substantial performance gains not only over clasp's default configuration and the earlier version of claspfolio, but also over manually tuned configurations of clasp.
Research in rodents has shown that dietary vitamin A reduces body fat by enhancing fat mobilisation and energy utilisation; however, their effects in growing dogs remain unclear. In the present study, we evaluated the development of body weight and body composition and compared observed energy intake with predicted energy intake in forty-nine puppies from two breeds (twenty-four Labrador Retriever (LAB) and twenty-five Miniature Schnauzer (MS)). A total of four different diets with increasing vitamin A content between 5.24 and 104.80 mu mol retinol (5000-100 000 IU vitamin A)/4184 kJ (1000 kcal) metabolisable energy were fed from the age of 8 weeks up to 52 (MS) and 78 weeks (LAB). The daily energy intake was recorded throughout the experimental period. The body condition score was evaluated weekly using a seven-category system, and food allowances were adjusted to maintain optimal body condition. Body composition was assessed at the age of 26 and 52 weeks for both breeds and at the age of 78 weeks for the LAB breed only using dual-energy X-ray absorptiometry. The growth curves of the dogs followed a breed-specific pattern. However, data on energy intake showed considerable variability between the two breeds as well as when compared with predicted energy intake. In conclusion, the data show that energy intakes of puppies particularly during early growth are highly variable; however, the growth pattern and body composition of the LAB and MS breeds are not affected by the intake of vitamin A at levels up to 104.80 mu mol retinol (100 000 IU vitamin A)/4184 kJ (1000 kcal).
The complementary advantages of high-rate Global Positioning System (GPS) and accelerometer observations for measuring seismic ground motion have been recognised in previous research. Here we propose an approach of tight integration of GPS and accelerometer measurements. The baseline shifts of the accelerometer are introduced as unknown parameters and estimated by a random walk process in the Precise Point Positioning (PPP) solution. To demonstrate the performance of the new strategy, we carried out several experiments using collocated GPS and accelerometer. The experimental results show that the baseline shifts of the accelerometer are automatically corrected, and high precision coseismic information of strong ground motion can be obtained in real-time. Additionally, the convergence and precision of the PPP is improved by the combined solution.
Object and action naming in Russian- and German- speaking monolingual and bilingual children*
(2014)
The present study investigates the influence of word category on naming performance in two populations: bilingual and monolingual children. The question is whether and, if so, to what extent monolingual and bilingual children differ with respect to noun and verb naming and whether a noun bias exists in the lexical abilities of bilingual children. Picture naming of objects and actions by Russian-German bilingual children (aged 4-7 years) was compared to age-matched monolingual children. The results clearly demonstrate a naming deficit of bilingual children in comparison to monolingual children that increases with age. Noun learning is more fragile in bilingual contexts than is verb learning. In bilingual language acquisition, nouns do not predominate over verbs as much as is seen in monolingual German and Russian children. The results are discussed with respect to semantic-conceptual aspects and language-specific features of nouns and verbs, and the impact of input on the acquisition of these word categories.
Bats are important components in tropical mammal assemblages. Unravelling the mechanisms allowing multiple syntopic bat species to coexist can provide insights into community ecology. However, dietary information on component species of these assemblages is often difficult to obtain. Here we measuredstable carbon and nitrogen isotopes in hair samples clipped from the backs of 94 specimens to indirectly examine whether trophic niche differentiation and microhabitat segregation explain the coexistence of 16 bat species at Ankarana, northern Madagascar. The assemblage ranged over 4.4% in delta N-15 and was structured into two trophic levels with phytophagous Pteropodidae as primary consumers (c. 3% enriched over plants) and different insectivorous bats as secondary consumers (c. 4% enriched over primary consumers). Bat species utilizing different microhabitats formed distinct isotopic clusters (metric analyses of delta C-13-delta N-15 bi-plots), but taxa foraging in the same microhabitat did not show more pronounced trophic differentiation than those occupying different microhabitats. As revealed by multivariate analyses, no discernible feeding competition was found in the local assemblage amongst congeneric species as compared with non-congeners. In contrast to ecological niche theory, but in accordance with studies on New and Old World bat assemblages, competitive interactions appear to be relaxed at Ankarana and not a prevailing structuring force.
Regular and irregular inflection in children's production has been examined in many previous studies. Yet, little is known about the processes involved in children's recognition of inflected words. To gain insight into how children process inflected words, the current study examines regular -t and irregular -n participles of German using the cross-modal priming technique testing 108 monolingual German-speaking children in two age groups (group I, mean age: 8;4, group II, mean age: 9;9) and a control group of.. adults. Although both age groups of children had the same full priming effect as adults for -t forms, only children of age group II showed an adult-like (partial) priming effect for -n participles. We argue that children (within the age range tested) employ the same mechanisms for regular inflection as adults but that the lexical retrieval processes required for irregular forms become more efficient when children get older.
This study investigates whether number dissimilarities on subject and object DPs facilitate the comprehension of subject-and object-extracted centre-embedded relative clauses in children with Grammatical Specific Language Impairment (G-SLI). We compared the performance of a group of English-speaking children with G-SLI (mean age: 12; 11) with that of two groups of younger typically developing (TD) children, matched on grammar and receptive vocabulary, respectively. All groups were more accurate on subject-extracted relative clauses than object-extracted ones and, crucially, they all showed greater accuracy for sentences with dissimilar number features (i.e., one singular, one plural) on the head noun and the embedded DP. These findings are interpreted in the light of current psycholinguistic models of sentence comprehension in TD children and provide further insight into the linguistic nature of G-SLI.
Two experiments tested how faithfully German children aged 4; 5 to 5; 6 reproduce ditransitive sentences that are unmarked or marked with respect to word order and focus (Exp1) or definiteness (Exp2). Adopting an optimality theory (OT) approach, it is assumed that in the German adult grammar word order is ranked lower than focus and definiteness. Faithfulness of children's reproductions decreased as markedness of inputs increased; unmarked structures were reproduced most faithfully and unfaithful outputs had most often an unmarked form. Consistent with the OT proposal, children were more tolerant against inputs marked for word order than for focus; in conflict with the proposal, children were less tolerant against inputs marked for word order than for definiteness. Our results suggest that the linearization of objects in German double object constructions is affected by focus and definiteness, but that prosodic principles may have an impact on the position of a focused constituent.
Masked priming research with late (non-native) bilinguals has reported facilitation effects following morphologically derived prime words (scanner - scan). However, unlike for native speakers, there are suggestions that purely orthographic prime-target overlap (scandal - scan) also produces priming in non-native visual word recognition. Our study directly compares orthographically related and derived prime-target pairs. While native readers showed morphological but not formal overlap priming, the two prime types yielded the same magnitudes of facilitation for non-natives. We argue that early word recognition processes in a non-native language are more influenced by surface-form properties than in one's native language.
In the aftermath of the severe flooding in Central Europe in August 2002, a number of changes in flood policies were launched in Germany and other European countries, aiming at improved risk management. The question arises as to whether these changes have already had an impact on the residents' ability to cope with floods, and whether flood-affected private households are now better prepared than they were in 2002. Therefore, computer-aided telephone interviews with private households in Germany that suffered from property damage due to flooding in 2005, 2006, 2010 or 2011 were performed and analysed with respect to flood awareness, precaution, preparedness and recovery. The data were compared to a similar investigation conducted after the flood in 2002.
After the flood in 2002, the level of private precautions taken increased considerably. One contributing factor is the fact that, in general, a larger proportion of people knew that they were at risk of flooding. The best level of precaution was found before the flood events in 2006 and 2011. The main reason for this might be that residents had more experience with flooding than residents affected in 2005 or 2010. Yet, overall, flood experience and knowledge did not necessarily result in building retrofitting or flood-proofing measures, which are considered as mitigating damages most effectively. Hence, investments still need to be stimulated in order to reduce future damage more efficiently.
Early warning and emergency responses were substantially influenced by flood characteristics. In contrast to flood-affected people in 2006 or 2011, people affected by flooding in 2005 or 2010 had to deal with shorter lead times and therefore had less time to take emergency measures. Yet, the lower level of emergency measures taken also resulted from the people's lack of flood experience and insufficient knowledge of how to protect themselves. Overall, it was noticeable that these residents suffered from higher losses. Therefore, it is important to further improve early warning systems and communication channels, particularly in hilly areas with rapid-onset flooding.
Extreme weather events are likely to occur more often under climate change and the resulting effects on ecosystems could lead to a further acceleration of climate change. But not all extreme weather events lead to extreme ecosystem response. Here, we focus on hazardous ecosystem behaviour and identify coinciding weather conditions. We use a simple probabilistic risk assessment based on time series of ecosystem behaviour and climate conditions. Given the risk assessment terminology, vulnerability and risk for the previously defined hazard are estimated on the basis of observed hazardous ecosystem behaviour.
We apply this approach to extreme responses of terrestrial ecosystems to drought, defining the hazard as a negative net biome productivity over a 12-month period. We show an application for two selected sites using data for 1981-2010 and then apply the method to the pan-European scale for the same period, based on numerical modelling results (LPJmL for ecosystem behaviour; ERA-Interim data for climate).
Our site-specific results demonstrate the applicability of the proposed method, using the SPEI to describe the climate condition. The site in Spain provides an example of vulnerability to drought because the expected value of the SPEI is 0.4 lower for hazardous than for non-hazardous ecosystem behaviour. In northern Germany, on the contrary, the site is not vulnerable to drought because the SPEI expectation values imply wetter conditions in the hazard case than in the non-hazard case.
At the pan-European scale, ecosystem vulnerability to drought is calculated in the Mediterranean and temperate region, whereas Scandinavian ecosystems are vulnerable under conditions without water shortages. These first model- based applications indicate the conceptual advantages of the proposed method by focusing on the identification of critical weather conditions for which we observe hazardous ecosystem behaviour in the analysed data set. Application of the method to empirical time series and to future climate would be important next steps to test the approach.
This study investigates the spatial and temporal distributions of 14 key arboreal taxa and their driving forces during the last 22,000 calendar years before ad 1950 (kyr BP) using a taxonomically harmonized and temporally standardized fossil pollen dataset with a 500-year resolution from the eastern part of continental Asia. Logistic regression was used to estimate pollen abundance thresholds for vegetation occurrence (presence or dominance), based on modern pollen data and present ranges of 14 taxa in China. Our investigation reveals marked changes in spatial and temporal distributions of the major arboreal taxa. The thermophilous (Castanea, Castanopsis, Cyclobalanopsis, Fagus, Pterocarya) and eurythermal (Juglans, Quercus, Tilia, Ulmus) broadleaved tree taxa were restricted to the current tropical or subtropical areas of China during the Last Glacial Maximum (LGM) and spread northward since c. 14.5 kyr BP. Betula and conifer taxa (Abies, Picea, Pinus), in contrast, retained a wider distribution during the LGM and showed no distinct expansion direction during the Late Glacial. Since the late mid-Holocene, the abundance but not the spatial extent of most trees decreased. The changes in spatial and temporal distributions for the 14 taxa are a reflection of climate changes, in particular monsoonal moisture, and, in the late Holocene, human impact. The post-LGM expansion patterns in eastern continental China seem to be different from those reported for Europe and North America, for example, the westward spread for eurythermal broadleaved taxa.
This study examines the course and driving forces of recent vegetation change in the Mongolian steppe. A sediment core covering the last 55years from a small closed-basin lake in central Mongolia was analyzed for its multi-proxy record at annual resolution. Pollen analysis shows that highest abundances of planted Poaceae and highest vegetation diversity occurred during 1977-1992, reflecting agricultural development in the lake area. A decrease in diversity and an increase in Artemisia abundance after 1992 indicate enhanced vegetation degradation in recent times, most probably because of overgrazing and farmland abandonment. Human impact is the main factor for the vegetation degradation within the past decades as revealed by a series of redundancy analyses, while climate change and soil erosion play subordinate roles. High Pediastrum (a green algae) influx, high atomic total organic carbon/total nitrogen (TOC/TN) ratios, abundant coarse detrital grains, and the decrease of C-13(org) and N-15 since about 1977 but particularly after 1992 indicate that abundant terrestrial organic matter and nutrients were transported into the lake and caused lake eutrophication, presumably because of intensified land use. Thus, we infer that the transition to a market economy in Mongolia since the early 1990s not only caused dramatic vegetation degradation but also affected the lake ecosystem through anthropogenic changes in the catchment area.
Two of a kind?
(2014)
School attacks are attracting increasing attention in aggression research. Recent systematic analyses provided new insights into offense and offender characteristics. Less is known about attacks in institutes of higher education (e.g., universities). It is therefore questionable whether the term “school attack” should be limited to institutions of general education or could be extended to institutions of higher education. Scientific literature is divided in distinguishing or unifying these two groups and reports similarities as well as differences. We researched 232 school attacks and 45 attacks in institutes of higher education throughout the world and conducted systematic comparisons between the two groups. The analyses yielded differences in offender (e.g., age, migration background) and offense characteristics (e.g., weapons, suicide rates), and some similarities (e.g., gender). Most differences can apparently be accounted for by offenders’ age and situational influences. We discuss the implications of our findings for future research and the development of preventative measures.
Leaking comprises observable behavior or statements that signal intentions of committing a violent offense and is considered an important warning sign for school shootings. School staff who are confronted with leaking have to assess its seriousness and react appropriately - a difficult task, because knowledge about leaking is sparse. The present study, therefore, examined how frequently leaking occurs in schools and how teachers identify leaking and respond to it. To achieve this aim, we informed teachers from eight schools in Germany about the definition of leaking and other warning signs and risk factors for school shootings in a one-hour information session. Teachers were then asked to report cases of leaking over a six- to nine-month period and to answer a questionnaire on leaking and its treatment after the information session and six to nine months later. Our results suggest that leaking is a relevant problem in German schools. Teachers mostly rated the information session positively and benefited in several aspects (e.g. reported more perceived courses of action or improved knowledge about leaking), but also expressed a constant need for support. Our findings highlight teachers' needs for further support and training and may be used in the planning of prevention measures for school shootings.
Although politicization is a perennial research topic in public administration to investigate relationships between ministers and civil servants, the concept still lacks clarification. This article contributes to this literature by systematically identifying different conceptualizations of politicization and suggests a typology including three politicization mechanisms to strengthen the political responsiveness of the ministerial bureaucracy: formal, functional and administrative politicization. The typology is empirically validated through a comparative case analysis of politicization mechanisms in Germany, Belgium, the UK and Denmark. The empirical analysis further refines the general idea of Western democracies becoming ‘simply’ more politicized, by illustrating how some politicization mechanisms do not continue to increase, but stabilize – at least for the time being.
Background Transcatheter aortic-valve implantation (TAVI) is an established alternative therapy in patients with severe aortic stenosis and a high surgical risk. Despite a rapid growth in its use, very few data exist about the efficacy of cardiac rehabilitation (CR) in these patients. We assessed the hypothesis that patients after TAVI benefit from CR, compared to patients after surgical aortic-valve replacement (sAVR).
Methods From September 2009 to August 2011, 442 consecutive patients after TAVI (n=76) or sAVR (n=366) were referred to a 3-week CR. Data regarding patient characteristics as well as changes of functional (6-min walk test. 6-MWT), bicycle exercise test), and emotional status (Hospital Anxiety and Depression Scale) were retrospectively evaluated and compared between groups after propensity score adjustment.
Results Patients after TAVI were significantly older (p<0.001), more female (p<0.001), and had more often coronary artery disease (p=0.027), renal failure (p=0.012) and a pacemaker (p=0.032). During CR, distance in 6-MWT (both groups p0.001) and exercise capacity (sAVR p0.001, TAVI p0.05) significantly increased in both groups. Only patients after sAVR demonstrated a significant reduction in anxiety and depression (p0.001). After propensity scores adjustment, changes were not significantly different between sAVR and TAVI, with the exception of 6-MWT (p=0.004).
Conclusions Patients after TAVI benefit from cardiac rehabilitation despite their older age and comorbidities. CR is a helpful tool to maintain independency for daily life activities and participation in socio-cultural life.
Background: Chronic kidney disease (CKD) is a frequent comorbidity among elderly patients and those with cardiovascular disease. CKD carries prognostic relevance. We aimed to describe patient characteristics, risk factor management and control status of patients in cardiac rehabilitation (CR), differentiated by presence or absence of CKD.
Design and methods: Data from 92,071 inpatients with adequate information to calculate glomerular filtration rate (GFR) based on the Cockcroft-Gault formula were analyzed at the beginning and the end of a 3-week CR stay. CKD was defined as estimated GFR <60 ml/min/1.73 m(2).
Results: Compared with non-CKD patients, CKD patients were significantly older (72.0 versus 58.0 years) and more often had diabetes mellitus, arterial hypertension, and atherothrombotic manifestations (previous stroke, peripheral arterial disease), but fewer were current or previous smokers had a CHD family history. Exercise capacity was much lower in CKD (59 vs. 92Watts). Fewer patients with CKD were treated with percutaneous coronary intervention (PCI), but more had coronary artery bypass graft (CABG) surgery. Patients with CKD compared with non-CKD less frequently received statins, acetylsalicylic acid (ASA), clopidogrel, beta blockers, and angiotensin converting enzyme (ACE) inhibitors, and more frequently received angiotensin receptor blockers, insulin and oral anticoagulants. In CKD, mean low density lipoprotein cholesterol (LDL-C), total cholesterol, and high density lipoprotein cholesterol (HDL-C) were slightly higher at baseline, while triglycerides were substantially lower. This lipid pattern did not change at the discharge visit, but overall control rates for all described parameters (with the exception of HDL-C) were improved substantially. At discharge, systolic blood pressure (BP) was higher in CKD (124 versus 121 mmHg) and diastolic BP was lower (72 versus 74 mmHg). At discharge, 68.7% of CKD versus 71.9% of non-CKD patients had LDL-C <100 mg/dl. Physical fitness on exercise testing improved substantially in both groups. When the Modification of Diet in Renal Disease (MDRD) formula was used for CKD classification, there was no clinically relevant change in these results.
Conclusion: Within a short period of 3-4 weeks, CR led to substantial improvements in key risk factors such as lipid profile, blood pressure, and physical fitness for all patients, even if CKD was present.
Background: Knowing and, if necessary, altering competitive athletes' real attitudes towards the use of banned performance-enhancing substances is an important goal of worldwide doping prevention efforts. However athletes will not always be willing to reporting their real opinions. Reaction time-based attitude tests help conceal the ultimate goal of measurement from the participant and impede strategic answering. This study investigated how well a reaction time-based attitude test discriminated between athletes who were doping and those who were not. We investigated whether athletes whose urine samples were positive for at least one banned substance (dopers) evaluated doping more favorably than clean athletes (non-dopers).
Methods: We approached a group of 61 male competitive bodybuilders and collected urine samples for biochemical testing. The pictorial doping Brief Implicit Association Test (BIAT) was used for attitude measurement. This test quantifies the difference in response latencies (in milliseconds) to stimuli representing related concepts (i.e. doping-dislike/like-[health food]).
Results: Prohibited substances were found in 43% of all tested urine samples. Dopers had more lenient attitudes to doping than non-dopers (Hedges's g = -0.76). D-scores greater than -0.57 (CI95 = -0.72 to -0.46) might be indicative of a rather lenient attitude to doping. In urine samples evidence of administration of combinations of substances, complementary administration of substances to treat side effects and use of stimulants to promote loss of body fat was common.
Conclusion: This study demonstrates that athletes' attitudes to doping can be assessed indirectly with a reaction time-based test, and that their attitudes are related to their behavior. Although bodybuilders may be more willing to reveal their attitude to doping than other athletes, these results still provide evidence that the pictorial doping BIAT may be useful in athletes from other sports, perhaps as a complementary measure in evaluations of the effectiveness of doping prevention interventions.
Background
The Amazon molly, Poecilia formosa (Teleostei: Poeciliinae) is an unisexual, all-female species. It evolved through the hybridisation of two closely related sexual species and exhibits clonal reproduction by sperm dependent parthenogenesis (or gynogenesis) where the sperm of a parental species is only used to activate embryogenesis of the apomictic, diploid eggs but does not contribute genetic material to the offspring.
Here we provide and describe the first de novo assembled transcriptome of the Amazon molly in comparison with its maternal ancestor, the Atlantic molly Poecilia mexicana. The transcriptome data were produced through sequencing of single end libraries (100 bp) with the Illumina sequencing technique.
Results
83,504,382 reads for the Amazon molly and 81,625,840 for the Atlantic molly were assembled into 127,283 and 78,961 contigs for the Amazon molly and the Atlantic molly, respectively. 63% resp. 57% of the contigs could be annotated with gene ontology terms after sequence similarity comparisons. Furthermore, we were able to identify genes normally involved in reproduction and especially in meiosis also in the transcriptome dataset of the apomictic reproducing Amazon molly.
Conclusions
We assembled and annotated the transcriptome of a non-model organism, the Amazon molly, without a reference genome (de novo). The obtained dataset is a fundamental resource for future research in functional and expression analysis. Also, the presence of 30 meiosis-specific genes within a species where no meiosis is known to take place is remarkable and raises new questions for future research.
Background: Cross-sectional studies detected associations between physical fitness, living area, and sports participation in children. Yet, their scientific value is limited because the identification of cause-and-effect relationships is not possible. In a longitudinal approach, we examined the effects of living area and sports club participation on physical fitness development in primary school children from classes 3 to 6.
Methods: One-hundred and seventy-two children (age: 9-12 years; sex: 69 girls, 103 boys) were tested for their physical fitness (i.e., endurance [9-min run], speed [50-m sprint], lower- [triple hop] and upper-extremity muscle strength [1-kg ball push], flexibility [stand-and-reach], and coordination [star coordination run]). Living area (i.e., urban or rural) and sports club participation were assessed using parent questionnaire.
Results: Over the 4 year study period, urban compared to rural children showed significantly better performance development for upper- (p = 0.009, ES = 0.16) and lower-extremity strength (p < 0.001, ES = 0.22). Further, significantly better performance development were found for endurance (p = 0.08, ES = 0.19) and lower-extremity strength (p = 0.024, ES = 0.23) for children continuously participating in sports clubs compared to their non-participating peers.
Conclusions: Our findings suggest that sport club programs with appealing arrangements appear to represent a good means to promote physical fitness in children living in rural areas.
Background: Doping attitude is a key variable in predicting athletes' intention to use forbidden performance enhancing drugs. Indirect reaction-time based attitude tests, such as the implicit association test, conceal the ultimate goal of measurement from the participant better than questionnaires. Indirect tests are especially useful when socially sensitive constructs such as attitudes towards doping need to be described. The present study serves the development and validation of a novel picture-based brief implicit association test (BIAT) for testing athletes' attitudes towards doping in sport. It shall provide the basis for a transnationally compatible research instrument able to harmonize anti-doping research efforts.
Method: Following a known-group differences validation strategy, the doping attitudes of 43 athletes from bodybuilding (representative for a highly doping prone sport) and handball (as a contrast group) were compared using the picture-based doping-BIAT. The Performance Enhancement Attitude Scale (PEAS) was employed as a corresponding direct measure in order to additionally validate the results.
Results: As expected, in the group of bodybuilders, indirectly measured doping attitudes as tested with the picture-based doping-BIAT were significantly less negative (eta(2) = .11). The doping-BIAT and PEAS scores correlated significantly at r = .50 for bodybuilders, and not significantly at r = .36 for handball players. There was a low error rate (7%) and a satisfactory internal consistency (r(dagger dagger) = .66) for the picture-based doping-BIAT.
Conclusions: The picture-based doping-BIAT constitutes a psychometrically tested method, ready to be adopted by the international research community. The test can be administered via the internet. All test material is available "open source". The test might be implemented, for example, as a new effect-measure in the evaluation of prevention programs.
The nature of the links between speech production and perception has been the subject of longstanding debate. The present study investigated the articulatory parameter of tongue height and the acoustic F1–F0 difference for the phonological distinction of vowel height in American English front vowels. Multiple repetitions of /i, ɪ, e, ɛ, æ/ in [(h)Vd] sequences were recorded in seven adult speakers. Articulatory (ultrasound) and acoustic data were collected simultaneously to provide a direct comparison of variability in vowel production in both domains. Results showed idiosyncratic patterns of articulation for contrasting the three front vowel pairs /i-ɪ/, /e-ɛ/, and /ɛ-æ/ across subjects, with the degree of variability in vowel articulation comparable to that observed in the acoustics for all seven participants. However, contrary to what was expected, some speakers showed reversals for tongue height for /ɪ/-/e/ that were also reflected in acoustics, with F1 higher for /ɪ/ than for /e/. The data suggest the phonological distinction of height is conveyed via speaker-specific articulatory-acoustic patterns that do not strictly match features descriptions. However, the acoustic signal is faithful to the articulatory configuration that generated it, carrying the crucial information for perceptual contrast.
Previous studies suggest that there are special timing relations in syllable onsets. The consonants are assumed to be timed, on the one hand, with the vocalic nucleus and, on the other hand, with each other. These competing timing relations result in the C-center effect. However, the C-center effect has not consistently been found in languages with complex onsets. Moreover, it has occasionally been found in languages disallowing complex onsets. The present study investigates onset timing in German while discussing alternative explanations (not related to bonding) for the timing patterns observed. Six German speakers were recorded via Electromagnetic Articulography. The corpus contained items with four clusters (/sk/, /kv/, /gl/, and /pl/). The clusters occur in word-initial position, word-medial position, and across a word boundary preceding different vowels. The results suggest that segmental properties (i.e., oral-laryngeal coordination, coarticulatory resistance) determine the observed timing patterns, and specifically the absence or presence of the C-center effect.
Rezensiertes Werk:
George, Rosemary Marangoly, Indian English and the Fiction of National Literature - Cambridge: Cambridge University Press, 2013. - Hb. viii, 285 pp. - (Zeitschrift für Anglistik und Amerikanistik ; 62(4)) ISBN 978-1-107-04000-7.
In the Posthomerica references to an omnipotent fate or to the power of the gods are strikingly frequent. Modern scholarship has often treated this as Stoic. Closer reading reveals that Quintus is, on the one hand, following the Homeric concept of double motivation, according to which humans can be motivated by a deity only to an act that conforms to their character and for which they are responsible. On the other hand, Quintus gives these statements on responsibility to characters who are trying to excuse their own acts to themselves and, particularly, to others, i.e. they are motivated contextually. It would be non-Stoic to excuse oneself for a bad deed by reference to an almighty fate. It seems that Quintus, by presenting this tension, wanted the reader to reconsider and reflect
on the different concepts.
Moderne Kraftfahrzeuge verfügen über eine Vielzahl an Sensoren, welche für einen reibungslosen technischen Betrieb benötigt werden. Hierzu zählen neben fahrzeugspezifischen Sensoren (wie z.B. Motordrehzahl und Fahrzeuggeschwindigkeit) auch umweltspezifische Sensoren (wie z.B. Luftdruck und Umgebungstemperatur). Durch die zunehmende technische Vernetzung wird es möglich, diese Daten der Kraftfahrzeugelektronik aus dem Fahrzeug heraus für die verschiedensten Zwecke zu verwenden.
Die vorliegende Arbeit soll einen Beitrag dazu leisten, diese neue Art an massenhaften Daten im Sinne des Konzepts der „Extended Floating Car Data“ (XFCD) als Geoinformationen nutzbar zu machen und diese für raumzeitliche Visualisierungen (zur visuellen Analyse) anwenden zu können. In diesem Zusammenhang wird speziell die Perspektive des Umwelt- und Verkehrsmonitoring betrachtet, wobei die Anforderungen und Potentiale mit Hilfe von Experteninterviews untersucht werden. Es stellt sich die Frage, welche Daten durch die Kraftfahrzeugelektronik geliefert und wie diese möglichst automatisiert erfasst, verarbeitet, visualisiert und öffentlich bereitgestellt werden können. Neben theoretischen und technischen Grundlagen zur Datenerfassung und -nutzung liegt der Fokus auf den Methoden der kartographischen Visualisierung. Dabei soll der Frage nachgegangenen werden, ob eine technische Implementierung ausschließlich unter Verwendung von Open Source Software möglich ist. Das Ziel der Arbeit bildet ein zweigliedriger Ansatz, welcher zum einen die Visualisierung für ein exemplarisch gewähltes Anwendungsszenario und zum anderen die prototypische Implementierung von der Datenerfassung im Fahrzeug unter Verwendung der gesetzlich vorgeschriebenen „On Board Diagnose“-Schnittstelle und einem Smartphone-gestützten Ablauf bis zur webbasierten Visualisierung umfasst.
Downscaling of microfluidic cell culture and detection devices for electrochemical monitoring has mostly focused on miniaturization of the microfluidic chips which are often designed for specific applications and therefore lack functional flexibility. We present a compact microfluidic cell culture and electrochemical analysis platform with in-built fluid handling and detection, enabling complete cell based assays comprising on-line electrode cleaning, sterilization, surface functionalization, cell seeding, cultivation and electrochemical real-time monitoring of cellular dynamics. To demonstrate the versatility and multifunctionality of the platform, we explored amperometric monitoring of intracellular redox activity in yeast (Saccharomyces cerevisiae) and detection of exocytotically released dopamine from rat pheochromocytoma cells (PC12). Electrochemical impedance spectroscopy was used in both applications for monitoring cell sedimentation and adhesion as well as proliferation in the case of PC12 cells. The influence of flow rate on the signal amplitude in the detection of redox metabolism as well as the effect of mechanical stimulation on dopamine release were demonstrated using the programmable fluid handling capability. The here presented platform is aimed at applications utilizing cell based assays, ranging from e.g. monitoring of drug effects in pharmacological studies, characterization of neural stem cell differentiation, and screening of genetically modified microorganisms to environmental monitoring.
Hemolysis, the rupturing of red blood cells, can result from numerous medical conditions (in vivo) or occur after collecting blood specimen or extracting plasma and serum out of whole blood (in vitro). In clinical laboratory practice, hemolysis can be a serious problem due to its potential to bias detection of various analytes or biomarkers. Here we present the first ‘‘mix-and-measure’’ method to assess the degree of hemolysis in biosamples using luminescence spectroscopy. Luminescent terbium complexes (LTC) were studied in the presence of free hemoglobin (Hb) as indicators for hemolysis in TRIS-buffer, and in fresh human plasma with absorption, excitation and emission measurements. Our findings indicate dynamic as well as resonance energy transfer (FRET) between the LTC and the porphyrin ligand of hemoglobin. This transfer leads to a decrease in luminescence intensity and decay time even at nanomolar hemoglobin concentrations either in buffer or plasma. Luminescent terbium complexes are very sensitive to free hemoglobin in buffer and blood plasma. Due to the instant change in luminescence properties of the LTC in presence of Hb it is possible to access the concentration of hemoglobin via spectroscopic methods without incubation time or further treatment of the sample thus enabling a rapid and sensitive detection of hemolysis in clinical diagnostics.
Surface modification with thermoresponsive polymer brushes for a switchable electrochemical sensor
(2014)
Elaboration of switchable surfaces represents an interesting way for the development of a new generation of electrochemical sensors. In this paper, a method for growing thermoresponsive polymer brushes from a gold surface pre-modified with polyethyleneimine (PEI), subsequent layer-by-layer polyelectrolyte assembly and adsorption of a charged macroinitiator is described. We propose an easy method for monitoring the coil-to-globule phase transition of the polymer brush using an electrochemical quartz crystal microbalance with dissipation (E-QCM-D). The surface of these polymer modified electrodes shows reversible switching from the swollen to the collapsed state with temperature. As demonstrated from E-QCM-D measurements using an original signal processing method, the switch is operating in three reversible steps related to different interfacial viscosities. Moreover, it is shown that the one electron oxidation of ferrocene carboxylic acid is dramatically affected by the change from the swollen to the collapsed state of the polymer brush, showing a spectacular 86% decrease of the charge transfer resistance between the two states.
Two-photon polymerization of hydrogels – versatile solutions to fabricate well-defined 3D structures
(2014)
Hydrogels are cross-linked water-containing polymer networks that are formed by physical, ionic or covalent interactions. In recent years, they have attracted significant attention because of their unique physical properties, which make them promising materials for numerous applications in food and cosmetic processing, as well as in drug delivery and tissue engineering. Hydrogels are highly water-swellable materials, which can considerably increase in volume without losing cohesion, are biocompatible and possess excellent tissue-like physical properties, which can mimic in vivo conditions. When combined with highly precise manufacturing technologies, such as two-photon polymerization (2PP), well-defined three-dimensional structures can be obtained. These structures can become scaffolds for selective cell-entrapping, cell/drug delivery, sensing and prosthetic implants in regenerative medicine. 2PP has been distinguished from other rapid prototyping methods because it is a non-invasive and efficient approach for hydrogel cross-linking. This review discusses the 2PP-based fabrication of 3D hydrogel structures and their potential applications in biotechnology. A brief overview regarding the 2PP methodology and hydrogel properties relevant to biomedical applications is given together with a review of the most important recent achievements in the field.
Hemocompatible materials are needed for internal and extracorporeal biomedical applications, which should be realizable by reducing protein and thrombocyte adhesion to such materials. Polyethers have been demonstrated to be highly efficient in this respect on smooth surfaces. Here, we investigate the grafting of oligo- and polyglycerols to rough poly(ether imide) membranes as a polymer relevant to biomedical applications and show the reduction of protein and thrombocyte adhesion as well as thrombocyte activation. It could be demonstrated that, by performing surface grafting with oligo- and polyglycerols of relatively high polydispersity (>1.5) and several reactive groups for surface anchoring, full surface shielding can be reached, which leads to reduced protein adsorption of albumin and fibrinogen. In addition, adherent thrombocytes were not activated. This could be clearly shown by immunostaining adherent proteins and analyzing the thrombocyte covered area. The presented work provides an important strategy for the development of application relevant hemocompatible 3D structured materials.
Polyglycolide (PGA) is a biodegradable polymer with multiple applications in the medical sector. Here the synthesis of high molecular weight polyglycolide by ring-opening polymerization of diglycolide is reported. For the first time stabilizer free supercritical carbon dioxide (scCO2) was used as a reaction medium. scCO2 allowed for a reduction in reaction temperature compared to conventional processes. Together with the lowering of monomer concentration and consequently reduced heat generation compared to bulk reactions thermal decomposition of the product occurring already during polymerization is strongly reduced. The reaction temperatures and pressures were varied between 120 and 150 °C and 145 to 1400 bar. Tin(II) ethyl hexanoate and 1-dodecanol were used as catalyst and initiator, respectively. The highest number average molecular weight of 31 200 g mol−1 was obtained in 5 hours from polymerization at 120 °C and 530 bar. In all cases the products were obtained as a dry white powder. Remarkably, independent of molecular weight the melting temperatures were always at (219 ± 2) °C.
The large-scale green synthesis of graphene-type two-dimensional materials is still challenging. Herein, we describe the ionothermal synthesis of carbon-based composites from fructose in the iron-containing ionic liquid 1-butyl-3-methylimidazolium tetrachloridoferrate(III), [Bmim][FeCl4] serving as solvent, catalyst, and template for product formation. The resulting composites consist of oligo-layer graphite nanoflakes and iron carbide particles. The mesoporosity, strong magnetic moment, and high specific surface area of the composites make them attractive for water purification with facile magnetic separation. Moreover, Fe3Cfree graphite can be obtained via acid etching, providing access to fairly large amounts of graphite material. The current approach is versatile and scalable, and thus opens the door to ionothermal synthesis towards the larger-scale synthesis of materials that are, although not made via a sustainable process, useful for water treatment such as the removal of organic molecules.
Catalytic bio–chemo and bio–bio tandem oxidation reactions for amide and carboxylic acid synthesis
(2014)
A catalytic toolbox for three different water-based one-pot cascades to convert aryl alcohols to amides and acids and cyclic amines to lactams, involving combination of oxidative enzymes (monoamine oxidase, xanthine dehydrogenase, galactose oxidase and laccase) and chemical oxidants (TBHP or CuI(cat)/H2O2) at mild temperatures, is presented. Mutually compatible conditions were found to afford products in good to excellent yields.
Zinc deficiency has a fundamental influence on the immune defense, with multiple effects on different immune cells, resulting in a major impairment of human health. Monocytes and macrophages are among the immune cells that are most fundamentally affected by zinc, but the impact of zinc on these cells is still far from being completely understood. Therefore, this study investigates the influence of zinc deficiency on monocytes of healthy human donors. Peripheral blood mononuclear cells, which include monocytes, were cultured under zinc deficient conditions for 3 days. This was achieved by two different methods: by application of the membrane permeable chelator N,N,N0´,N0´-tetrakis-(2-pyridylmethyl)ethylenediamine (TPEN) or by removal of zinc from the culture medium using a CHELEX 100 resin. Subsequently, monocyte functions were analyzed in response to Escherichia coli, Staphylococcus aureus, and Streptococcus pneumoniae. Zinc depletion had differential effects. On the one hand, elimination of bacterial pathogens by phagocytosis and oxidative burst was elevated. On the other hand, the production of the inflammatory cytokines tumor necrosis factor (TNF)-a and interleukin (IL)-6 was reduced. This suggests that monocytes shift from intercellular communication to basic innate defensive functions in response to zinc deficiency. These results were obtained regardless of the method by which zinc deficiency was achieved. However, CHELEX-treated medium strongly augmented cytokine production, independently from its capability for zinc removal. This side-effect severely limits the use of CHELEX for investigating the effects of zinc deficiency on innate immunity.
The synthesis of two novel types of π-expanded coumarins has been developed. Modified Knoevenagel bis-condensation afforded 3,9-dioxa-perylene-2,8-diones. Subsequent oxidative aromatic coupling or light driven electrocyclization reaction led to dibenzo-1,7-dioxacoronene-2,8-dione. Unparalleled synthetic simplicity, straightforward purification and superb optical properties have the potential to bring these perylene and coronene analogs towards various applications.
Photoinduced excitation energy transfer and accompanying charge separation are elucidated for a supramolecular system of a single fullerene covalently linked to six pyropheophorbide-a dye molecules. Molecular dynamics simulations are performed to gain an atomistic picture of the architecture and the surrounding solvent. Excitation energy transfer among the dye molecules and electron transfer from the excited dyes to the fullerene are described by a mixed quantum–classical version of the Förster rate and the semiclassical Marcus rate, respectively. The mean characteristic time of energy redistribution lies in the range of 10 ps, while electron transfer proceeds within 150 ps. In between, on a 20 to 50 ps time-scale, conformational changes take place in the system. This temporal hierarchy of processes guarantees efficient charge separation, if the structure is exposed to a solvent. The fast energy transfer can adopt the dye excitation to the actual conformation. In this sense, the probability to achieve charge separation is large enough since any dominance of unfavorable conformations that exhibit a large dye–fullerene distance is circumvented. And the slow electron transfer may realize an averaging with respect to different conformations. To confirm the reliability of our computations, ensemble measurements on the charge separation dynamics are simulated and a very good agreement with the experimental data is obtained.
Based on extensive Monte Carlo simulations and analytical considerations we study the electrostatically driven adsorption of flexible polyelectrolyte chains onto charged Janus nanospheres. These net-neutral colloids are composed of two equally but oppositely charged hemispheres. The critical binding conditions for polyelectrolyte chains are analysed as function of the radius of the Janus particle and its surface charge density, as well as the salt concentration in the ambient solution. Specifically for the adsorption of finite-length polyelectrolyte chains onto Janus nanoparticles, we demonstrate that the critical adsorption conditions drastically differ when the size of the Janus particle or the screening length of the electrolyte are varied. We compare the scaling laws obtained for the adsorption–desorption threshold to the known results for uniformly charged spherical particles, observing significant disparities. We also contrast the changes to the polyelectrolyte chain conformations close to the surface of the Janus nanoparticles as compared to those for simple spherical particles. Finally, we discuss experimentally relevant physico-chemical systems for which our simulations results may become important. In particular, we observe similar trends with polyelectrolyte complexation with oppositely but heterogeneously charged proteins.
Formation of a Eu(III) borate solid species from a weak Eu(III) borate complex in aqueous solution
(2014)
In the presence of polyborates (detected by 11B-NMR) the formation of a weak Eu(III) borate complex (lg β11 ∼ 2, estimated) was observed by time-resolved laser-induced fluorescence spectroscopy (TRLFS). This complex is a precursor for the formation of a solid Eu(III) borate species. The formation of this solid in solution was investigated by TRLFS as a function of the total boron concentration: the lower the total boron concentration, the slower is the solid formation. The solid Eu(III) borate was characterized by IR spectroscopy, powder XRD and solid-state TRLFS. The determination of the europium to boron ratio portends the existence of pentaborate units in the amorphous solid.
A feasible approach to construct multilayer films of sulfonated polyanilines – PMSA1 and PABMSA1 – containing different ratios of aniline, 2-methoxyaniline-5-sulfonic acid (MAS) and 3-aminobenzoic acid (AB), with the entrapped redox enzyme pyrroloquinoline quinone-dependent glucose dehydrogenase (PQQ-GDH) on Au and ITO electrode surfaces, is described. The formation of layers has been followed and confirmed by electrochemical impedance spectroscopy (EIS), which demonstrates that the multilayer assembly can be achieved in a progressive and uniform manner. The gold and ITO electrodes subsequently modified with PMSA1:PQQ-GDH and PABMSA1 films are studied by cyclic voltammetry (CV) and UV-Vis spectroscopy which show a significant direct bioelectrocatalytical response to the oxidation of the substrate glucose without any additional mediator. This response correlates linearly with the number of deposited layers. Furthermore, the constructed polymer/enzyme multilayer system exhibits a rather good long-term stability, since the catalytic current response is maintained for more than 60% of the initial value even after two weeks of storage. This verifies that a productive interaction of the enzyme embedded in the film of substituted polyaniline can be used as a basis for the construction of bioelectronic units, which are useful as indicators for processes liberating glucose and allowing optical and electrochemical transduction.
As an engineering material derived from renewable resources, wood possesses excellent mechanical properties in view of its light weight but also has some disadvantages such as low dimensional stability upon moisture changes and low durability against biological attack. Polymerization of hydrophobic monomers in the cell wall is one of the potential approaches to improve the dimensional stability of wood. A major challenge is to insert hydrophobic monomers into the hydrophilic environment of the cell walls, without increasing the bulk density of the material due to lumen filling. Here, we report on an innovative and simple method to insert styrene monomers into tosylated cell walls (i.e. –OH groups from natural wood polymers are reacted with tosyl chloride) and carry out free radical polymerization under relatively mild conditions, generating low wood weight gains. In-depth SEM and confocal Raman microscopy analysis are applied to reveal the distribution of the polystyrene in the cell walls and the lumen. The embedding of polystyrene in wood results in reduced water uptake by the wood cell walls, a significant increase in dimensional stability, as well as slightly improved mechanical properties measured by nanoindentation.
Herein, we report the chain-growth tin-free room temperature polymerization method to synthesize n-type perylene diimide-dithiophene-based conjugated polymers (PPDIT2s) suitable for solar cell and transistor applications. The palladium/electron-rich tri-tert-butylphosphine catalyst is effective to enable the chain-growth polymerization of anion-radical monomer Br-TPDIT-Br/Zn to PPDIT2 with a molecular weight up to Mw ≈ 50 kg mol−1 and moderate polydispersity. This is the second example of the polymerization of unusual anion-radical aromatic complexes formed in a reaction of active Zn and electron-deficient diimide-based aryl halides. As such, the discovered polymerization method is not a specific reactivity feature of the naphthalene-diimide derivatives but is rather a general polymerization tool. This is an important finding, given the significantly higher maximum external quantum efficiency that can be reached with PDI-based copolymers (32–45%) in all-polymer solar cells compared to NDI-based materials (15–30%). Our studies revealed that PPDIT2 synthesized by the new method and the previously published polymer prepared by step-growth Stille polycondensation show similar electron mobility and all-polymer solar cell performance. At the same time, the polymerization reported herein has several technological advantages as it proceeds relatively fast at room temperature and does not involve toxic tin-based compounds. Because several chain-growth polymerization reactions are well-suited for the preparation of well-defined multi-functional polymer architectures, the next target is to explore the utility of the discovered polymerization in the synthesis of end-functionalized polymers and block copolymers. Such materials would be helpful to improve the nanoscale morphology of polymer blends in all-polymer solar cells.
Materials derived from renewable resources are highly desirable in view of more sustainable manufacturing. Among the available natural materials, wood is one of the key candidates, because of its excellent mechanical properties. However, wood and wood-based materials in engineering applications suffer from various restraints, such as dimensional instability upon humidity changes. Several wood modification treatments increase water repellence, but the insertion of hydrophobic polymers can result in a composite material which cannot be considered as renewable anymore. In this study, we report on the grafting of the fully biodegradable poly(ε-caprolactone) (PCL) inside the wood cell walls by Sn(Oct)2 catalysed ring-opening polymerization (ROP). The presence of polyester chains within the wood cell wall structure is monitored by confocal Raman imaging and spectroscopy as well as scanning electron microscopy. Physical tests reveal that the modified wood is more hydrophobic due to the bulking of the cell wall structure with the polyester chains, which results in a novel fully biodegradable wood material with improved dimensional stability.
A new functional luminescent lanthanide complex (LLC) has been synthesized with terbium as a central lanthanide ion and biotin as a functional moiety. Unlike in typical lanthanide complexes assembled via carboxylic moieties, in the presented complex, four phosphate groups are chelating the central lanthanide ion. This special chemical assembly enhances the complex stability in phosphate buffers conventionally used in biochemistry. The complex synthesis strategy and photophysical properties are described as well as the performance in time-resolved Förster Resonance Energy Transfer (FRET) assays. In those assays, this biotin-LLC transferred energy either to acceptor organic dyes (Cy5 or AF680) labelled on streptavidin or to quantum dots (QD655 or QD705) surface-functionalised with streptavidins. The permanent spatial donor–acceptor proximity is assured through strong and stable biotin–streptavidin binding. The energy transfer is evidenced from the quenching observed in donor emission and from a decrease in donor luminescence decay, both associated with simultaneous increase in acceptor intensity and in the decay time. The dye-based assays are realised in TRIS and in PBS, whereas QD-based systems are studied in borate buffer. The delayed emission analysis allows for quantifying the recognition process and for auto-fluorescence-free detection, which is particularly relevant for application in bioanalysis. In accordance with Förster theory, Förster-radii (R0) were found to be around 60 Å for organic dyes and around 105 Å for QDs. The FRET efficiency (η) reached 80% and 25% for dye and QD acceptors, respectively. Physical donor–acceptor distances (r) have been determined in the range 45–60 Å for organic dye acceptors, while for acceptor QDs between 120 Å and 145 Å. This newly synthesised biotin-LLC extends the class of highly sensitive analytical tools to be applied in the bioanalytical methods such as time-resolved fluoroimmunoassays (TR-FIA), luminescent imaging and biosensing.
Dieser Artikel adressiert zwei bisher nur wenig untersuchte Aspekte der Führungsforschung: Führungsverhalten im öffentlichen Sektor und Faktoren die Führungsverhalten beeinflussen. Mittels einer Fallstudie in der Bundesagentur für Arbeit werden explorativ Hypothesen über Einflussfaktoren des Führungsverhaltens aufgestellt. Die Studie kommt zu der Erkenntnis, dass eine oftmals angenommene Führungslücke im öffentlichen Sektor nicht bestätigt werden kann. Für das ausgeprägte Führungsverhalten, das in der Fallstudie beobachtet wurde, wird als Determinante die besondere Ausgestaltung des Managementsystems der Bundesagentur für Arbeit verantwortlich gemacht. Dazu gehört unter anderem das Performance Management System sowie die Führungskräfteauswahl und -entwicklung. Die Arbeit schließt mit Empfehlungen für weitere Forschungsansätze auf dem Gebiet der Führungsforschung im öffentlichen Sektor.
This essay approaches T. S. Eliot’s Four Quartets (1935–1942) from the perspectives of Eve Kosofsky Sedgwick’s critical practice of reparative reading and of Paul Ricoeur’s poststructuralist hermeneutics. It demonstrates that Sedgwick’s and Ricoeur’s approaches can be productively combined to investigate hermeneutic processes in which the textual energy of a dissemination of meaning is redirected by a reparative or integrative impulse. In Four Quartets, this impetus induces the creation of semantic innovation through a violation of semantic pertinence, that is, through novel, tensional and provisional connections between formerly separate textual elements and semantic units.
The system of German capitalisation seems to be based on dissimilar levels of linguistic description, i. e. semantics, morphology, and syntax. This leads to several competing scientific models as well as a large range of different rules which appear to be widely autonomous and incompatible with each other. This paper opens an integrative view on the topic by focussing on a pragmatic perspective, which is capable not only on integrating all major application areas of German capitalisation but also of motivating them. Based on theDiscourse Representation Theory (DRT) the text pragmatic model can add a functional perspective to established theories by making similar predictions on capitalisation but additionally specifying communicative reasons for them. Therefore it claims explanatory adequacy from the functional perspective.
Werner Mittenzwei’s article of 1967, the title of which coined the term “Brecht-Lukács-Debatte”, is widely considered as a milestone in the development of East German literary criticism towards an “emancipation” from party politics. By placing Mittenzwei’s contribution in the wider context of discussions about the literature of the GDR, within the SED and the writers’ union as well as at international conferences, this article attempts to trace the emergence of “Umfunktionierung” both as a key term and in its official approval by the party.
Diese Arbeit befasst sich mit den sogenannten relativähnlichen Sätzen im Frühneuhochdeutschen und leistet somit einen Beitrag zur Subordinationsforschung des älteren Deutsch. Relativähnliche Sätze sind formal durch ein satzinitiales anaphorisches d-Element und die Endstellung des finiten Verbs gekennzeichnet. Semantisch gesehen beziehen sie sich auf den vorangehenden Satz als Ganzes, indem sie ihn in bestimmter Weise weiterführen oder kommentieren. In der bisherigen Forschung werden diese Sätze satztypologisch als Hauptsätze mit Verbendstellung analysiert (vgl. dazu Maurer 1926, Behaghel 1932 und Lötscher 2000). Nach der ausführlichen Diskussion der formalen Abhängigkeitsmarker im älteren Deutsch sowie anhand einer umfangreichen korpusbasierten Untersuchung wird in dieser Arbeit gezeigt, dass relativähnliche Sätze im Frühneuhochdeutschen auch als abhängige Sätze - analog zu den weiterführenden Relativsätzen im Gegenwartsdeutschen - analysiert werden können. Die weiterführenden Relativsätze im Gegenwartsdeutschen enthalten satzinitial auch ein anaphorisches Element, das sich auf das Gesagte in dem vorangehenden Satz bezieht. Verbendstellung weisen sie ebenfalls auf (mehr zur Grammatik der weiterführenden Relativsätze vgl. insb. Brandt 1990 und Holler 2005). Über die Untersuchung relativähnlicher Sätze hinaus befasst sich diese Arbeit ausführlich mit formalen Abhängigkeitsmarkern des älteren Deutsch, wie Verbendstellung, Einleiter und afinite Konstruktion.
עבירה לשמה
(2014)
A Transgression for the Sake of God -‘Averah li-shmah: A Tale of a Radical Idea in Talmudic Literature
All cultures, religions, and ethical or legal systems struggle with the role intention plays in evaluating actions. The Talmud compellingly elaborates on the notion of intention through the radical concept that “A sin committed for the sake of God [averah li-shmah] is greater than a commandment fulfilled not for the sake of God [mi-mizvah she-lo li-shmah].” The Babylonian Talmud attributes this concept—which challenges one of rabbinic Judaism’s most fundamental dogmas, the obligation to fulfill the commandments and avoid sin—to R. Nahman b. Isaac (RNBI), a renowned 4th century Amora. Considering the normative character of the rabbinic culture in which Halakhah (Jewish religious law) plays such a central role, this concept, seems almost like a foreign body in the Talmudic corpus.
The study focuses on the linguistic stratum of RNBI’s statement. By tracking the development of the meanings and uses of the word ‘li-shmah’ the research locates RNBI’s statement as part of the broader Talmudic discourse evaluating two levels of performing religious actions ‘li-shmah/she-lo li-shmah’. Since we wish to explain the word ‘li-shmah’ consistently both times it appears in the statement, the best translation would be ‘for the sake of God’. This translation is based on the linguistic connection between the word ‘li-shmah’ and the term ‘le-shem shamayim’ (for the sake of God) that appears in several rabbinic sources. This linguistic connection is also the key to identifying the possible root of RNBI’s concept. RNBI bolsters his idea by quoting a verse about Jael, thus implying that Jael sinned for the sake of God. The research describes at least five statements in Sages’ Literature that attribute sins for the sake of God to other biblical figures, all the while using the term ‘le-shem shamim’. Therefore we may presume that RNBI’s concept has evolved from the exegetical notion of attributing sin for the sake of God to biblical figures.
To understand the way RNBI’s statement was accepted in Talmudic culture, we must explore the textual witnesses to the literary frame of RNBI’s statement: the Talmudic sugya (Nazir 23a; Horayot 10b). We possess five versions of the sugya’s dialectical structure. Comparison of these versions, allows us to reconstruct the earlier dialectical structure, from which the familiar versions developed. The radical potential of RNBI’s statement led to cultural activity, in the transmission of the sugya, in an effort to mitigate it. This activity is reflected in late additions to the sugya identified by our research—which should be viewed as a process of self-censorship for ideological reasons.
This research explores a fundamental issue in rabbinic world: the immanent contradiction between law and intention. The research depicts in detail the movement of a radical idea from the margins culture to mainstream - in this case into the Babylonian Talmud. Therefore, the findings of this research provide substantial insight into our understanding of the interpretive process and of conceptual adaptation in rabbinic culture.
HPI Future SOC Lab
(2014)
The “HPI Future SOC Lab” is a cooperation of the Hasso-Plattner-Institut (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. 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 2014. Selected projects have presented their results on April 9th and September 29th 2014 at the Future SOC Lab Day events.
Der Begriff Altruismus geht auf Auguste Comte, den Gründer der Soziologie zurück. Es bezeichnet zugleich Uneigennütziges als auch selbstloses Verhalten von Individuen und wird daher oft dem egoistischen Verhalten gegenübergestellt. Die zahlreichen Anhänger des rationalen-egoistischem Paradigma lehnen die Idee der altruistischen Natur des Menschen meist ab, wohingegen die Anhänger des Altruismus nicht nur schwerer zu finden sind, sondern vor allem die Idee einer rein egoistischen Natur ablehnen. Diese Arbeit untersucht die Altruismus-Begriffe der Soziologen Emile Durkheim und James Coleman, welche die Kontroverse zwischen den unterschiedlichen Paradigmen wiederspiegeln. Ziel dieser Arbeit wird es sein, die unterschiedlichen Altruismus-Konzepte von Durkheim und Coleman zunächst vorzustellen, anschließend einander gegenüberzustellen und darauf folgend zu untersuchen, welche Auswirkung ihre unterschiedlichen Weltanschauungen, Prämissen und Methodologien auf ihr Verständnis von der Logik des selbstlosen Gebens haben. Durch den Vergleich soll versucht werden die Grenzen beider Theorien aufzuzeigen und damit auch ein Ausweg aus dem methodologischem Disput, welcher folglich zur Überwindung der Altruismus-Egoismus Kontroverse beitragen soll.
Inhalt:
Alexander von Humboldt-Forschungsstelle: Ingo Schwarz zum 65. Geburtstag
Ottmar Ette: Findung und Erfindung einer Leserschaft. Neuere Editionsprojekte zu Alexander von Humboldt als Grundlage und Herausforderung künftigen Forschens
Eberhard Knobloch: Alexandre de Humboldt et le Marquis de Laplace
Oliver Schwarz: Alexander von Humboldt als astronomischer Arbeiter, Diskussionspartner und Ideengeber
Petra Werner: Innenwelten und bleiche Gärten. Alexander von Humboldt untertage und in der Caripe-Höhle
Christian Suckow: Alexander von Humboldt in Ust’-Kamenogorsk
Anne Jobst: Neue Briefe Christian Gottfried Ehrenbergs an Alexander von Humboldt
Thomas Schmuck: Humboldt, Baer und die Evolution
Manfred Ringmacher: Zwei Briefe auf Guaraní in Alexander von Humboldts Handschrift
Ute Tintemann: Julius Klaproths Mithridates-Projekt, Alexander von Humboldt und das Verlagshaus Cotta
Ulrike Leitner: „Ja! Wenn Berlin Bonn wäre!“ Friedrich Rückerts Berufung nach Berlin
Frank Holl: „Zur Freiheit bestimmt“ – Alexander von Humboldts Blick auf die Kulturen der Welt
Sebastian Panwitz: Das Humboldt-Mendelssohn-Haus Jägerstraße 22. Ein Quellenfund
Laura Péaud: Du Mexique à l‘Oural : l‘expertise humboldtienne au service du politique
Bärbel Holtz: „Cicerone“ des Königs? Alexander von Humboldt und Friedrich Wilhelm III.
Menso Folkerts: Ein unerwartetes Zusammentreffen in Sanssouci. Alexander von Humboldt und Karl Ludwig Hencke an der Tafel Friedrich Wilhelms IV.
Ulrich Päßler: Preußens Mann in Washington. Fünf Briefe Friedrich von Gerolts an Alexander von Humboldt (1858/1859)
Bill Roba: German-Iowan Strategies in Celebrating the Centennial of Alexander von Humboldt’s Birth
Regina Mikosch: Ingo Schwarz‘ Veröffentlichungen zur Alexander von Humboldt
Über die Autoren
Über die Autoren
(2014)
Luhmann in the Contact Zone
(2014)
Preußens Mann in Washington
(2014)
Der Diplomat und preußische Gesandte in Washington, Friedrich von Gerolt, versorgte Humboldt während der 1840er und 1850er Jahre mit Informationen über die politischen und geistigen Entwicklungen auf dem nordamerikanischen Kontinent. Humboldt seinerseits förderte in Berlin Gerolts Karriere und protegierte ihn bei Hofe. In den von Ulrich Päßler vorgestellten Briefen aus den Jahren 1858/59 spricht Gerolt einige Entwicklungen in den Vereinigten Staaten an, die deren (geo-)politische Stellung in der Welt entscheidend prägen sollten.
Friedrich Wilhelm III., seit 1797 König von Preußen, garantierte am 19. November 1805 dem 36-jährigen Humboldt eine Pension von jährlich 2.500 Talern. Nur wenige Tage danach ernannte er ihn zu seinem Kammerherrn. Was Humboldt nicht ahnen konnte war, dass dieser Dienst 54 Jahre währen sollte. Bärbel Holtz beschreibt die bisher wenig untersuchte Beziehung des Monarchen zum Forschungsreisenden.
Du Mexique à l‘Oural
(2014)
Das Haus in der Jägerstraße, welches um 1800 die Nummer 22 erhielt, ist bekannt als das Elternhaus der Brüder Wilhelm und Alexander von Humboldt. Ob Alexander von Humboldt hier oder im elterlichen Schloß geboren wurde, ist unklar, da er selbst im Verlauf seines Lebens zu dieser Frage widersprüchliche Angaben machte. Das Rätsel des Geburtsortes bleibt vorerst weiter ungelöst. Es ist aber eine Akte aus Privatbesitz aufgetaucht, die zur Geschichte des Hauses Jägerstraße 22 zahlreiche bislang unbekannte Dokumente enthält. Sebastian Panwitz stellt einen Abschnitt daraus vor.