@phdthesis{Sotiropoulou2019, author = {Sotiropoulou, Stavroula}, title = {Pleiotropy of phonetic indices in the expression of syllabic organization}, doi = {10.25932/publishup-54639}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-546399}, school = {Universit{\"a}t Potsdam}, pages = {xv, 184}, year = {2019}, abstract = {This dissertation is concerned with the relation between qualitative phonological organization in the form of syllabic structure and continuous phonetics, that is, the spatial and temporal dimensions of vocal tract action that express syllabic structure. The main claim of the dissertation is twofold. First, we argue that syllabic organization exerts multiple effects on the spatio-temporal properties of the segments that partake in that organization. That is, there is no unique or privileged exponent of syllabic organization. Rather, syllabic organization is expressed in a pleiotropy of phonetic indices. Second, we claim that a better understanding of the relation between qualitative phonological organization and continuous phonetics is reached when one considers how the string of segments (over which the nature of the phonological organization is assessed) responds to perturbations (scaling of phonetic variables) of localized properties (such as durations) within that string. Specifically, variation in phonetic variables and more specifically prosodic variation is a crucial key to understanding the nature of the link between (phonological) syllabic organization and the phonetic spatio-temporal manifestation of that organization. The effects of prosodic variation on segmental properties and on the overlap between the segments, we argue, offer the right pathway to discover patterns related to syllabic organization. In our approach, to uncover evidence for global organization, the sequence of segments partaking in that organization as well as properties of these segments or their relations with one another must be somehow locally varied. The consequences of such variation on the rest of the sequence can then be used to unveil the span of organization. When local perturbations to segments or relations between adjacent segments have effects that ripple through the rest of the sequence, this is evidence that organization is global. If instead local perturbations stay local with no consequences for the rest of the whole, this indicates that organization is local.}, language = {en} } @phdthesis{Ruschel2019, author = {Ruschel, Matthias}, title = {Das Preußische Erbrecht in der Judikatur des Berliner Obertribunals in den Jahren 1836 bis 1865}, doi = {10.25932/publishup-52779}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-527798}, school = {Universit{\"a}t Potsdam}, pages = {283}, year = {2019}, abstract = {Die Dissertation befasst sich mit dem Allgemeinen Preußischen Landrecht von 1794 und der hierzu ergangenen Rechtsprechung des Berliner Obertribunals. Im Fokus der Untersuchung stehen die erbrechtlichen Regelungen des Landrechts und deren Anwendung sowie Auslegung in der Judikatur des h{\"o}chsten preußischen Gerichts. Der Forschungsgegenstand ergibt sich aus dem im Landrecht kodifizierten speziellen Gesetzesverst{\"a}ndnisses. Nach diesem sollte die Gesetzesauslegung durch die Rechtsprechung auf ein Minimum, n{\"a}mlich die Auslegung allein anhand des Wortlauts der Regelung reduziert werden, um dem absolutistischen Regierungsanspruch der preußischen Monarchen, namentlich Friedrich des Großen, hinreichend Rechnung zu tragen. In diesem Kontext wird der Frage nachgegangen, inwieweit das preußische Obertribunal das im Landrecht statuierte „Auslegungsverbot" beachtet hat und in welchen F{\"a}llen sich das Gericht von der Vorgabe emanzipierte und weitere Auslegungsmethoden anwendete und sich so eine unabh{\"a}ngige Rechtsprechung entwickeln konnte. Die Arbeit gliedert sich in drei Hauptabschnitte. Im Anschluss an die Einleitung, in der zun{\"a}chst die rechtshistorische Bedeutung des Landrechts und des Erbrechts sowie der Untersuchungsgegenstand umrissen werden, folgt die Darstellung der Entstehungsgeschichte des Landrechts und des Berliner Obertribunals. Hieran schließt sich in einem dritten Abschnitt eine Analyse der erbrechtlichen Vorschriften des Landrechts an. In dieser wird auf die Entstehungsgeschichte der verschiedenen erbrechtlichen Institute wie beispielsweise der gesetzlichen und gewillk{\"u}rten Erbfolge, dem Pflichtteilsrecht etc., unter Ber{\"u}cksichtigung des zeitgen{\"o}ssischen wissenschaftlichen Diskurses eingegangen. Im vierten Abschnitt geht es um die Judikate des Berliner Obertribunals aus den Jahren 1836-1865 in denen die zuvor dargestellten erbrechtlichen Regelungen entscheidungserheblich waren. Dabei wird der Forschungsfrage, inwieweit das Obertribunal das im Landrecht statuierte Auslegungsverbot beachtet hat und in welchen F{\"a}llen es von diesem abwich bzw. weitere Auslegungsmethoden anwendete, konkret nachgegangen wird. Insgesamt werden 26 Entscheidungen des Obertribunals unter dem Aspekt der Auslegungspraxis, der Kontinuit{\"a}t und der Beschleunigung der Rechtsprechung analysiert und ausgewertet.}, language = {de} } @phdthesis{Opitz2019, author = {Opitz, Fanny}, title = {Literarische Journalisten - journalistische Literaten}, publisher = {transcript}, address = {Bielefeld}, isbn = {978-3-8394-5460-2}, doi = {10.14361/9783839454602}, school = {Universit{\"a}t Potsdam}, year = {2019}, abstract = {W{\"a}hrend der hemds{\"a}rmelige Reporter lediglich f{\"u}r den Tag schreibt, schafft der Literat Texte f{\"u}r die Ewigkeit. Mit diesem {\"u}ber Jahrhunderte tradierten Klischee brechen zwei Autoren ganz bewusst, die in beiden Bereichen erfolgreich sind: Joseph Roth und Tom Wolfe - in Personalunion Journalisten wie Literaten - hinterfragen den Wertungsunterschied, der gemeinhin zwischen den Bereichen gemacht wird. Fanny Opitz zeichnet die diskursiven Umfelder nach, in denen die Debatte um die Leistung von Journalismus und Literatur breit gef{\"u}hrt wurde: im Deutschland der 1920er Jahre im Kontext der gesamtkulturellen Str{\"o}mung der Neuen Sachlichkeit und im US-amerikanischen New Journalism der 1960er und 1970er Jahre.}, language = {de} } @phdthesis{Doering2019, author = {D{\"o}ring, Matthias}, title = {The public encounter}, doi = {10.25932/publishup-50227}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-502276}, school = {Universit{\"a}t Potsdam}, pages = {xi, 115}, year = {2019}, abstract = {This thesis puts the citizen-state interaction at its center. Building on a comprehensive model incorporating various perspectives on this interaction, I derive selected research gaps. The three articles, comprising this thesis, tackle these gaps. A focal role plays the citizens' administrative literacy, the relevant competences and knowledge necessary to successfully interact with public organizations. The first article elaborates on the different dimensions of administrative literacy and develops a survey instrument to assess these. The second study shows that public employees change their behavior according to the competences that citizens display during public encounters. They treat citizens preferentially that are well prepared and able to persuade them of their application's potential. Thereby, they signal a higher success potential for bureaucratic success criteria which leads to the employees' cream-skimming behavior. The third article examines the dynamics of employees' communication strategies when recovering from a service failure. The study finds that different explanation strategies yield different effects on the client's frustration. While accepting the responsibility and explaining the reasons for a failure alleviates the frustration and anger, refusing the responsibility leads to no or even reinforcing effects on the client's frustration. The results emphasize the different dynamics that characterize the nature of citizen-state interactions and how they establish their short- and long-term outcomes.}, language = {en} } @phdthesis{Gong2019, author = {Gong, Chen Chris}, title = {Synchronization of coupled phase oscillators}, doi = {10.25932/publishup-48752}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-487522}, school = {Universit{\"a}t Potsdam}, pages = {xvii, 115}, year = {2019}, abstract = {Oscillatory systems under weak coupling can be described by the Kuramoto model of phase oscillators. Kuramoto phase oscillators have diverse applications ranging from phenomena such as communication between neurons and collective influences of political opinions, to engineered systems such as Josephson Junctions and synchronized electric power grids. This thesis includes the author's contribution to the theoretical framework of coupled Kuramoto oscillators and to the understanding of non-trivial N-body dynamical systems via their reduced mean-field dynamics. The main content of this thesis is composed of four parts. First, a partially integrable theory of globally coupled identical Kuramoto oscillators is extended to include pure higher-mode coupling. The extended theory is then applied to a non-trivial higher-mode coupled model, which has been found to exhibit asymmetric clustering. Using the developed theory, we could predict a number of features of the asymmetric clustering with only information of the initial state provided. The second part consists of an iterated discrete-map approach to simulate phase dynamics. The proposed map --- a Moebius map --- not only provides fast computation of phase synchronization, it also precisely reflects the underlying group structure of the dynamics. We then compare the iterated-map dynamics and various analogous continuous-time dynamics. We are able to replicate known phenomena such as the synchronization transition of the Kuramoto-Sakaguchi model of oscillators with distributed natural frequencies, and chimera states for identical oscillators under non-local coupling. The third part entails a particular model of repulsively coupled identical Kuramoto-Sakaguchi oscillators under common random forcing, which can be shown to be partially integrable. Via both numerical simulations and theoretical analysis, we determine that such a model cannot exhibit stationary multi-cluster states, contrary to the numerical findings in previous literature. Through further investigation, we find that the multi-clustering states reported previously occur due to the accumulation of discretization errors inherent in the integration algorithms, which introduce higher-mode couplings into the model. As a result, the partial integrability condition is violated. Lastly, we derive the microscopic cross-correlation of globally coupled non-identical Kuramoto oscillators under common fluctuating forcing. The effect of correlation arises naturally in finite populations, due to the non-trivial fluctuations of the meanfield. In an idealized model, we approximate the finite-sized fluctuation by a Gaussian white noise. The analytical approximation qualitatively matches the measurements in numerical experiments, however, due to other periodic components inherent in the fluctuations of the mean-field there still exist significant inconsistencies.}, language = {en} } @phdthesis{Stoll2019, author = {Stoll, Sarah}, title = {Giuseppe Prezzolini}, publisher = {be.bra wissenschaft}, address = {Berlin}, isbn = {978-3-95410-269-3}, school = {Universit{\"a}t Potsdam}, pages = {582}, year = {2019}, abstract = {Der Journalist Giuseppe Prezzolini (1882-1982) geh{\"o}rt zu den pr{\"a}genden italienischen Intellektuellen des 20. Jahrhunderts. Die von ihm begr{\"u}ndete Kulturzeitschrift »La Voce« bot einflussreichen Stimmen der Zeit eine B{\"u}hne, darunter Giovanni Gentile, Benedetto Croce oder Benito Mussolini. Durch seine publizistische Arbeit avancierte er zu einem festen intellektuellen Bezugspunkt konservativer Kreise Italiens. Seine Forderungen u. a. nach einer Neugr{\"u}ndung des italienischen Konservatismus abseits neofaschistischer Ideen begr{\"u}ndeten seinen umstrittenen Ruf als Antikonformist.}, language = {de} } @phdthesis{Bachsleitner2019, author = {Bachsleitner, Anna}, title = {Bildungsverl{\"a}ufe und soziale Ungleichheit vom Abitur bis zur Promotion}, school = {Universit{\"a}t Potsdam}, pages = {193}, year = {2019}, abstract = {{\"U}berg{\"a}nge im Bildungssystem sind zentrale Stationen f{\"u}r die Generierung von sozialer Ungleichheit. W{\"a}hrend die Bildungswege und die Bedeutung der sozialen Ungleichheit f{\"u}r den Schulbereich umfangreich untersucht wurden, liegen kaum Studien zu den nachschulischen Bildungsverl{\"a}ufen von Hochschulzugangsberechtigten und dem Einfluss der sozialen Herkunft bis zur Aufnahme einer Promotion vor. Daher ist es das Ziel der vorliegenden Arbeit, die Gestaltung nachschulischer Bildungsverl{\"a}ufe zu untersuchen sowie die Bedeutung der sozialen Herkunft vom Abitur bis zur Promotionsaufnahme zu analysieren. Den beiden Forschungsfragen wurde in vier Teilstudien nachgegangen. In Teilstudie 1 wurde die Relevanz von Merkmalen des Bildungsverlaufes f{\"u}r die Promotionsaufnahme untersucht. Der Schwerpunkt der drei folgenden Teilstudien lag auf der Bedeutung der sozialen Herkunft bei Aufnahme einer Promotion beziehungsweise der sozialen Ungleichheit in den relevanten Selektionsstufen des nachschulischen Bildungsverlaufs bis zur Promotionsaufnahme. In Teilstudie 2 wurden diesbez{\"u}glich soziale Herkunftseffekte bei der f{\"u}r eine Promotionsaufnahme bedeutsamen Wahl der Hochschulform untersucht, in Teilstudie 3 die Mechanismen hinter sozialen Herkunftseffekten bei Promotionsaufnahme analysiert und in Teilstudie 4 wurde soziale Ungleichheit bei Studienaufnahme und Promotionsaufnahme vergleichend betrachtet. Als Datengrundlage wurde die L{\"a}ngsschnittstudie BIJU (Bildungsverl{\"a}ufe und psychosoziale Entwicklung im Jugend- und jungen Erwachsenenalter) herangezogen. Die Befunde der Dissertation verweisen auf die Relevanz sozialer Ungleichheiten vom Eintritt in die Hochschule bis zum {\"U}bergang in die Promotion. Auch wenn ein abnehmender Herkunftseffekt vom {\"U}bertritt ins Studium zum {\"U}bertritt in die Promotion vorliegt, sind soziale Herkunftseffekte bei dem sp{\"a}ten Bildungs{\"u}bergang noch sichtbar. Zudem zeigt sich die Bedeutung von Pfadabh{\"a}ngigkeiten in Bildungsverl{\"a}ufen sowie von Leistungsunterschieden f{\"u}r eine Promotionsaufnahme.}, language = {de} } @phdthesis{Kerutt2019, author = {Kerutt, Josephine Victoria}, title = {The high-redshift voyage of Lyman alpha and Lyman continuum emission as told by MUSE}, doi = {10.25932/publishup-47881}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-478816}, school = {Universit{\"a}t Potsdam}, pages = {152}, year = {2019}, abstract = {Most of the matter in the universe consists of hydrogen. The hydrogen in the intergalactic medium (IGM), the matter between the galaxies, underwent a change of its ionisation state at the epoch of reionisation, at a redshift roughly between 6>z>10, or ~10^8 years after the Big Bang. At this time, the mostly neutral hydrogen in the IGM was ionised but the source of the responsible hydrogen ionising emission remains unclear. In this thesis I discuss the most likely candidates for the emission of this ionising radiation, which are a type of galaxy called Lyman alpha emitters (LAEs). As implied by their name, they emit Lyman alpha radiation, produced after a hydrogen atom has been ionised and recombines with a free electron. The ionising radiation itself (also called Lyman continuum emission) which is needed for this process inside the LAEs could also be responsible for ionising the IGM around those galaxies at the epoch of reionisation, given that enough Lyman continuum escapes. Through this mechanism, Lyman alpha and Lyman continuum radiation are closely linked and are both studied to better understand the properties of high redshift galaxies and the reionisation state of the universe. Before I can analyse their Lyman alpha emission lines and the escape of Lyman continuum emission from them, the first step is the detection and correct classification of LAEs in integral field spectroscopic data, specifically taken with the Multi-Unit Spectroscopic Explorer (MUSE). After detecting emission line objects in the MUSE data, the task of classifying them and determining their redshift is performed with the graphical user interface QtClassify, which I developed during the work on this thesis. It uses the strength of the combination of spectroscopic and photometric information that integral field spectroscopy offers to enable the user to quickly identify the nature of the detected emission lines. The reliable classification of LAEs and determination of their redshifts is a crucial first step towards an analysis of their properties. Through radiative transfer processes, the properties of the neutral hydrogen clouds in and around LAEs are imprinted on the shape of the Lyman alpha line. Thus after identifying the LAEs in the MUSE data, I analyse the properties of the Lyman alpha emission line, such as the equivalent width (EW) distribution, the asymmetry and width of the line as well as the double peak fraction. I challenge the common method of displaying EW distributions as histograms without taking the limits of the survey into account and construct a more independent EW distribution function that better reflects the properties of the underlying population of galaxies. I illustrate this by comparing the fraction of high EW objects between the two surveys MUSE-Wide and MUSE-Deep, both consisting of MUSE pointings (each with the size of one square arcminute) of different depths. In the 60 MUSE-Wide fields of one hour exposure time I find a fraction of objects with extreme EWs above EW_0>240A of ~20\%, while in the MUSE-Deep fields (9 fields with an exposure time of 10 hours and one with an exposure time of 31 hours) I find a fraction of only ~1\%, which is due to the differences in the limiting line flux of the surveys. The highest EW I measure is EW_0 = 600.63 +- 110A, which hints at an unusual underlying stellar population, possibly with a very low metallicity. With the knowledge of the redshifts and positions of the LAEs detected in the MUSE-Wide survey, I also look for Lyman continuum emission coming from these galaxies and analyse the connection between Lyman continuum emission and Lyman alpha emission. I use ancillary Hubble Space Telescope (HST) broadband photometry in the bands that contain the Lyman continuum and find six Lyman continuum leaker candidates. To test whether the Lyman continuum emission of LAEs is coming only from those individual objects or the whole population, I select LAEs that are most promising for the detection of Lyman continuum emission, based on their rest-frame UV continuum and Lyman alpha line shape properties. After this selection, I stack the broadband data of the resulting sample and detect a signal in Lyman continuum with a significance of S/N = 5.5, pointing towards a Lyman continuum escape fraction of ~80\%. If the signal is reliable, it strongly favours LAEs as the providers of the hydrogen ionising emission at the epoch of reionisation and beyond.}, language = {en} } @phdthesis{Kuberski2019, author = {Kuberski, Stephan R.}, title = {Fundamental motor laws and dynamics of speech}, doi = {10.25932/publishup-43771}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-437714}, school = {Universit{\"a}t Potsdam}, pages = {97}, year = {2019}, abstract = {The present work is a compilation of three original research articles submitted (or already published) in international peer-reviewed venues of the field of speech science. These three articles address the topics of fundamental motor laws in speech and dynamics of corresponding speech movements: 1. Kuberski, Stephan R. and Adamantios I. Gafos (2019). "The speed-curvature power law in tongue movements of repetitive speech". PLOS ONE 14(3). Public Library of Science. doi: 10.1371/journal.pone.0213851. 2. Kuberski, Stephan R. and Adamantios I. Gafos (In press). "Fitts' law in tongue movements of repetitive speech". Phonetica: International Journal of Phonetic Science. Karger Publishers. doi: 10.1159/000501644 3. Kuberski, Stephan R. and Adamantios I. Gafos (submitted). "Distinct phase space topologies of identical phonemic sequences". Language. Linguistic Society of America. The present work introduces a metronome-driven speech elicitation paradigm in which participants were asked to utter repetitive sequences of elementary consonant-vowel syllables. This paradigm, explicitly designed to cover speech rates from a substantially wider range than has been explored so far in previous work, is demonstrated to satisfy the important prerequisites for assessing so far difficult to access aspects of speech. Specifically, the paradigm's extensive speech rate manipulation enabled elicitation of a great range of movement speeds as well as movement durations and excursions of the relevant effectors. The presence of such variation is a prerequisite to assessing whether invariant relations between these and other parameters exist and thus provides the foundation for a rigorous evaluation of the two laws examined in the first two contributions of this work. In the data resulting from this paradigm, it is shown that speech movements obey the same fundamental laws as movements from other domains of motor control do. In particular, it is demonstrated that speech strongly adheres to the power law relation between speed and curvature of movement with a clear speech rate dependency of the power law's exponent. The often-sought or reported exponent of one third in the statement of the law is unique to a subclass of movements which corresponds to the range of faster rates under which a particular utterance is produced. For slower rates, significantly larger values than one third are observed. Furthermore, for the first time in speech this work uncovers evidence for the presence of Fitts' law. It is shown that, beyond a speaker-specific speech rate, speech movements of the tongue clearly obey Fitts' law by emergence of its characteristic linear relation between movement time and index of difficulty. For slower speech rates (when temporal pressure is small), no such relation is observed. The methods and datasets obtained in the two assessment above provide a rigorous foundation both for addressing implications for theories and models of speech as well as for better understanding the status of speech movements in the context of human movements in general. All modern theories of language rely on a fundamental segmental hypothesis according to which the phonological message of an utterance is represented by a sequence of segments or phonemes. It is commonly assumed that each of these phonemes can be mapped to some unit of speech motor action, a so-called speech gesture. For the first time here, it is demonstrated that the relation between the phonological description of simple utterances and the corresponding speech motor action is non-unique. Specifically, by the extensive speech rate manipulation in the herein used experimental paradigm it is demonstrated that speech exhibits clearly distinct dynamical organizations underlying the production of simple utterances. At slower speech rates, the dynamical organization underlying the repetitive production of elementary /CV/ syllables can be described by successive concatenations of closing and opening gestures, each with its own equilibrium point. As speech rate increases, the equilibria of opening and closing gestures are not equally stable yielding qualitatively different modes of organization with either a single equilibrium point of a combined opening-closing gesture or a periodic attractor unleashed by the disappearance of both equilibria. This observation, the non-uniqueness of the dynamical organization underlying what on the surface appear to be identical phonemic sequences, is an entirely new result in the domain of speech. Beyond that, the demonstration of periodic attractors in speech reveals that dynamical equilibrium point models do not account for all possible modes of speech motor behavior.}, language = {en} } @phdthesis{He2019, author = {He, Hai}, title = {Exploring and engineering formaldehyde assimilation}, doi = {10.25932/publishup-47386}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-473867}, school = {Universit{\"a}t Potsdam}, pages = {vi, 105}, year = {2019}, abstract = {Increasing concerns regarding the environmental impact of our chemical production have shifted attention towards possibilities for sustainable biotechnology. One-carbon (C1) compounds, including methane, methanol, formate and CO, are promising feedstocks for future bioindustry. CO2 is another interesting feedstock, as it can also be transformed using renewable energy to other C1 feedstocks for use. While formaldehyde is not suitable as a feedstock due to its high toxicity, it is a central intermediate in the process of C1 assimilation. This thesis explores formaldehyde metabolism and aims to engineer formaldehyde assimilation in the model organism Escherichia coli for the future C1-based bioindustry. The first chapter of the thesis aims to establish growth of E. coli on formaldehyde via the most efficient naturally occurring route, the ribulose monophosphate pathway. Linear variants of the pathway were constructed in multiple-gene knockouts strains, coupling E. coli growth to the activities of the key enzymes of the pathway. Formaldehyde-dependent growth was achieved in rationally designed strains. In the final strain, the synthetic pathway provides the cell with almost all biomass and energy requirements. In the second chapter, taking advantage of the unique feature of its reactivity, formaldehyde assimilation via condensation with glycine and pyruvate by two promiscuous aldolases was explored. Facilitated by these two reactions, the newly designed homoserine cycle is expected to support higher yields of a wide array of products than its counterparts. By dividing the pathway into segments and coupling them to the growth of dedicated strains, all pathway reactions were demonstrated to be sufficiently active. The work paves a way for future implementation of a highly efficient route for C1 feedstocks into commodity chemicals. In the third chapter, the in vivo rate of the spontaneous formaldehyde tetrahydrofolate condensation to methylene-tetrahydrofolate was assessed in order to evaluate its applicability as a biotechnological process. Tested within an E. coli strain deleted in essential genes for native methylene-tetrahydrofolate biosynthesis, the reaction was shown to support the production of this essential intermediate. However, only low growth rates were observed and only at high formaldehyde concentrations. Computational analysis dependent on in vivo evidence from this strain deduced the slow rate of this spontaneous reaction, thus ruling out its substantial contribution to growth on C1 feedstocks. The reactivity of formaldehyde makes it highly toxic. In the last chapter, the formation of thioproline, the condensation product of cysteine and formaldehyde, was confirmed to contribute this toxicity effect. Xaa-Pro aminopeptidase (PepP), which genetically links with folate metabolism, was shown to hydrolyze thioproline-containing peptides. Deleting pepP increased strain sensitivity to formaldehyde, pointing towards the toxicity of thioproline-containing peptides and the importance of their removal. The characterization in this study could be useful in handling this toxic intermediate. Overall, this thesis identified challenges related to formaldehyde metabolism and provided novel solutions towards a future bioindustry based on sustainable C1 feedstocks in which formaldehyde serves as a key intermediate.}, language = {en} }