TY - JOUR A1 - Vitello, Eugenia ED - Ambühl, Annemarie ED - Carlà-Uhink, Filippo ED - Rollinger, Christian ED - Walde, Christine T1 - Review of Emilio Zucchetti & Anna Maria Cimino (eds.): Antonio Gramsci and the Ancient World BT - London/New York: Routledge, Taylor & Francis Group, 2021 (= Routledge Monographs in Classical Studies), xiv + 387 pp., ISBN: 978-0-36-719314-0, £ 96.00 (hb.) JF - thersites 14 Y1 - 2022 U6 - https://doi.org/10.34679/thersites.vol14.203 SN - 2364-7612 VL - 2022 IS - 14 SP - 188 EP - 196 ER - TY - CHAP A1 - Vlugter, Peter A1 - Knott, Alistair T1 - A multi-speaker dialogue system for computer-aided language learning N2 - The main topic of this paper is how to configure a dialogue system to support computer-aided language learning. The paper also serves to introduce our new multi-speaker dialogue system, and highlight some of its novel features. Y1 - 2006 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-10208 ER - TY - JOUR A1 - Vogel, Ralf T1 - The simple generator JF - Linguistics in Potsdam N2 - I argue that the shift of explanatory burden from the generator to the evaluator in OT syntax – together with the difficulties that arise when we try to formulate a working theory of the interfaces of syntax – leads to a number of assumptions about syntactic structures in OT which are quite different from those typical of minimalist syntax: formal features, as driving forces behind syntactic movement, are useless, and derivational and representational economy are problematic for both empirical and conceptual reasons. The notion of markedness, central in Optimality Theory, is not fully compatible with the idea of synactic economy. Even more so, seemingly obvious cases of blocking by structural economy do not seem to result from grammar proper, but reflect (economical) aspects of language use. KW - OT syntax KW - generator KW - markedness KW - syntax-semantics interface KW - syntax-phonology interface Y1 - 2006 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-32338 SN - 1616-7392 SN - 1864-1857 IS - 25 SP - 99 EP - 136 ER - TY - JOUR A1 - Vogel, Ralf T1 - Dialectal variation in German 3-verb clusters BT - looking for the best analysis JF - Linguistics in Potsdam N2 - Content: 1 The Typology 1.1 Object Placement 2 Treatment of StG in terms of LF Movement – with and without Head Movement 3 An OT-solution in terms of linearisation (‘LF-to-PF-Mapping’) 3.1 The trigger for additional orders: Focus 3.2 Competitions 3.3 Summary 4 RP 4.1 LF Movement – with and without Head Movement 4.2 The OT-account for RP 4.3 Competitions 5 Summary Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-32516 SN - 1864-1857 SN - 1616-7392 VL - 22 SP - 83 EP - 118 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - JOUR A1 - Vogel, Ralf A1 - Frisch, Stefan T1 - The resolution of case conflicts BT - a pilot study JF - Linguistics in Potsdam N2 - This paper reports the results of a pilot study on the resolution of case conflicts in German free relative constructions. Section 1 gives a brief introduction into the phenomenon, section 2 presents the experiment and its results, section 3 ends the paper with a brief more general discussion. Y1 - 2003 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-32466 SN - 1616-7392 SN - 1864-1857 VL - 21 SP - 91 EP - 103 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - JOUR A1 - Vogel, Ralf A1 - Zugck, Marco T1 - Counting Markedness BT - a corpus investigation on German free relative constructions JF - Linguistics in Potsdam N2 - This paper reports the results of a corpus investigation on case conflicts in German argument free relative constructions. We investigate how corpus frequencies reflect the relative markedness of free relative and correlative constructions, the relative markedness of different case conflict configurations, and the relative markedness of different conflict resolution strategies. Section 1 introduces the conception of markedness as used in Optimality Theory. Section 2 introduces the facts about German free relative clauses, and section 3 presents the results of the corpus study. By and large, markedness and frequency go hand in hand. However, configurations at the highest end of the markedness scale rarely show up in corpus data, and for the configuration at the lowest end we found an unexpected outcome: the more marked structure is preferred. Y1 - 2003 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-32476 SN - 1864-1857 SN - 1616-7392 VL - 21 SP - 105 EP - 122 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - INPR A1 - Volosevich, Alexandra V. A1 - Meister, Claudia-Veronika T1 - Nonlinear interaction of Farley-Buneman waves N2 - The nonlinear interaction of waves excited by the modified two-stream instability (Farley-Buneman instability) is considered. It is found that, during the linear stage of wave growth, the enhanced pressure of the high-frequency part of the waves locally generates a ponderomotive force. This force acts on the plasma particles and redistributes them. Thus an additional electrostatic polarization field occurs, which influences the low-frequency part of the waves. Then, the low-frequency waves also cause a redistribution of the high-frequency waves. In the paper, a self-consistent system of equations is obtained, which describes the nonlinear interaction of the waves. It is shown that the considered mechanism of wave interaction causes a nonlinear stabilization of the high-frequency waves’ growth and a formation of local density structures of the charged particles. The density modifications of the charged particles during the non-linear stage of wave growth and the possible interval of aspect angles of the high-frequency waves are estimated. T3 - NLD Preprints - 52 Y1 - 1998 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-14851 ER - TY - JOUR A1 - von Moritz, Brescius T1 - Connecting the new world BT - Nets, mobility and progress in the age of Alexander von Humboldt N2 - This article explores the link between the profound technological transformations of the nineteenth century and the life and work of the Prussian scholar Alexander von Humboldt (1769-1859). It analyses how Humboldt sought to appropriate the revolutionary new communication and transportation technologies of the time in order to integrate the American continent into global networks of commercial, intellectual and material exchange. Recent scholarship on Humboldt’s expedition to the New World (1799-1804) has claimed that his descriptions of tropical landscapes opened up South America to a range of ‘transformative interventions’ (Pratt) by European capitalists and investors. These studies, however, have not analysed the motivations underlying Humboldt’s support for such intrusions into nature. Furthermore, they have not explored the role that such projects played in shaping Humboldt’s understanding of the forces behind the progress of societies. To comprehend Humboldt’s approval for human interventions in America’s natural world, this study first explores the role that eighteenth-century theories of progress and the notion of geographical determinism played in shaping his conception of civilisational development. It will look at concrete examples of transformative interventions in the American hemisphere that were actively proposed by Humboldt and intended to overcome natural obstacles to human interaction. These were the use of steamships, electric telegraphy, railroads and large-scale canals that together enabled global trade and communication to occur at an unprecedented pace. All these contemporary innovations will be linked to the four motifs of nets, mobility, progress and acceleration, which were driving forces behind the ‘transformation of the world’ that took place in the course of the nineteenth century. N2 - Dieser Artikel untersucht das Verhältnis zwischen den revolutionären technologischen Neuerungen des 19. Jahrhunderts und dem Leben und Wirken Alexander von Humboldts (1769-1859). Dabei wird gefragt, wie Humboldt versuchte, die neuen und sprichwörtlich bahnbrechenden Kommunikations- und Transporttechnologien seiner Zeit zu nutzen, um den amerikanischen Kontinent in globale kommerzielle und kulturelle Austauschprozesse zu integrieren. Jüngere Forschungen zu Humboldts amerikanischer Expedition (1799-1804) haben behauptet, dass seine Beschreibungen Südamerikas den Kontinent für zahlreiche ’transformative interventions’ (Pratt) von Seiten europäischer Kapitalisten und Investoren zugänglich gemacht hätten. Diese Studien haben jedoch nicht analysiert, aus welchen Motiven heraus Humboldt diese Eingriffe in die Natur unterstützte. Darüber hinaus wurde nicht der zentralen Frage nachgegangen, welche Rolle diese Projekte in Humboldts eigener Auffassung über die Kräfte des gesellschaftlichen Fortschritts gespielt haben. Um Humboldts Unterstützung für tiefgreifende Eingriffe in die Natur Amerikas nachvollziehen zu können, analysiert dieser Artikel zunächst, welche Rolle der ‚Geodeterminismus’ und die Fortschrittstheorien der Aufklärung in seinem Verständnis von zivilisatorischer Entwicklung spielten. Dabei sollen solche Beispiele menschlicher Interventionen in die Natur Amerikas untersucht werden, die Humboldt selbst aktiv förderte – nicht zuletzt, da sie geeignet schienen, ‚natürliche’ Barrieren für gesellschaftliche Austauschprozesse zu beseitigen. Dies waren vor allem die Nutzung von Dampfschiffen, elektrischer Telegrafie, Eisenbahnen und großangelegten Kanalprojekten, deren gebündelte Effekte zu einer signifikanten Beschleunigung von Welthandel und Kommunikationsprozessen führten. Diese zeitgenössischen Innovationen sollen mit den vier Motiven ‚Netz’, ‚Mobilität’, ‚Fortschritt’ und ‚Beschleunigung’ analytisch verbunden werden, da diese Faktoren eine zentrale Rolle für die ‚Verwandlung der Welt’ im 19. Jahrhundert spielten. N2 - Este artículo examina la relación entre las profundas transformaciones tecnológicas del siglo XIX y la vida y obra del estudioso prusiano Alexander von Humboldt (1769-1859). Para ello, analizaremos cómo Humboldt trató de apropiarse de las nuevas y revolucionarias tecnologías de comunicación y transporte de su tiempo, de cara a poder integrar el continente americano en redes globales de intercambio comercial, material e intelectual. Estudios recientes sobre la expedición de Humboldt al Nuevo Mundo (1799-1804) han demostrado que sus descripciones de los paisajes tropicales americanos abrieron Sudamérica a una serie de ‘intervenciones transformativas’ (Mary Louise Pratt) lideradas por capitalistas e inversores europeos. No obstante, estos estudios no han analizado las motivaciones que llevaron a Humboldt a prestar su apoyo a tamañas intrusiones en la naturaleza. Más aún, tampoco han intentado analizar cómo estos proyectos influyeron sobre Humboldt, sobre su manera de entender las fuerzas motoras que se escondían tras el progreso de las sociedades. Con el objetivo de entender la aprobación de Humboldt a las intervenciones humanas que se llevaron a cabo en el suelo americano, este estudio se centrará primero en explorar el papel que las teorías sobre el progreso del siglo XVIII, así como la noción de determinismo geográfico, tuvieron en la concepción que tenía el investigador prusiano del desarrollo de las civilizaciones. Se estudiarán, para ello, algunos casos concretos de intervenciones transformativas que se llevaron a cabo en el hemisferio americano y que, propuestas con entusiasmo por el mismo Humboldt, intentaron superar los obstáculos naturales que dificultaban la intervención humana. Nos referiremos, más particularmente, al uso de barcos a vapor, telégrafos eléctricos, vías férreas y canales de gran escala. En definitiva, elementos que dieron lugar, en su conjunto, a un comercio y una comunicación global que se llevaron a cabo a un ritmo sin precedentes. Una serie de innovaciones que habrá que relacionar con cuatro temas fundamentales: redes, movilidad, progreso y aceleración; fuerzas motoras de la ‘transformación del mundo’ que tuvo lugar a lo largo del siglo XIX. KW - Aufklärung KW - Beschleunigung KW - Fortschritt KW - Kommunikation KW - Mobilität KW - Netz KW - Transporttechnologie Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-62386 SN - 1617-5239 SN - 2568-3543 VL - XIII IS - 25 SP - 11 EP - 33 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - THES A1 - Vorogushyn, Sergiy T1 - Analysis of flood hazard under consideration of dike breaches T1 - Analyse der Hochwassergefährdung unter Berücksichtigung von Deichbrüchen N2 - River reaches protected by dikes exhibit high damage potential due to strong value accumulation in the hinterland areas. While providing an efficient protection against low magnitude flood events, dikes may fail under the load of extreme water levels and long flood durations. Hazard and risk assessments for river reaches protected by dikes have not adequately considered the fluvial inundation processes up to now. Particularly, the processes of dike failures and their influence on the hinterland inundation and flood wave propagation lack comprehensive consideration. This study focuses on the development and application of a new modelling system which allows a comprehensive flood hazard assessment along diked river reaches under consideration of dike failures. The proposed Inundation Hazard Assessment Model (IHAM) represents a hybrid probabilistic-deterministic model. It comprises three models interactively coupled at runtime. These are: (1) 1D unsteady hydrodynamic model of river channel and floodplain flow between dikes, (2) probabilistic dike breach model which determines possible dike breach locations, breach widths and breach outflow discharges, and (3) 2D raster-based diffusion wave storage cell model of the hinterland areas behind the dikes. Due to the unsteady nature of the 1D and 2D coupled models, the dependence between hydraulic load at various locations along the reach is explicitly considered. The probabilistic dike breach model describes dike failures due to three failure mechanisms: overtopping, piping and slope instability caused by the seepage flow through the dike core (micro-instability). The 2D storage cell model driven by the breach outflow boundary conditions computes an extended spectrum of flood intensity indicators such as water depth, flow velocity, impulse, inundation duration and rate of water rise. IHAM is embedded in a Monte Carlo simulation in order to account for the natural variability of the flood generation processes reflected in the form of input hydrographs and for the randomness of dike failures given by breach locations, times and widths. The model was developed and tested on a ca. 91 km heavily diked river reach on the German part of the Elbe River between gauges Torgau and Vockerode. The reach is characterised by low slope and fairly flat extended hinterland areas. The scenario calculations for the developed synthetic input hydrographs for the main river and tributary were carried out for floods with return periods of T = 100, 200, 500, 1000 a. Based on the modelling results, probabilistic dike hazard maps could be generated that indicate the failure probability of each discretised dike section for every scenario magnitude. In the disaggregated display mode, the dike hazard maps indicate the failure probabilities for each considered breach mechanism. Besides the binary inundation patterns that indicate the probability of raster cells being inundated, IHAM generates probabilistic flood hazard maps. These maps display spatial patterns of the considered flood intensity indicators and their associated return periods. Finally, scenarios of polder deployment for the extreme floods with T = 200, 500, 1000 were simulated with IHAM. The developed IHAM simulation system represents a new scientific tool for studying fluvial inundation dynamics under extreme conditions incorporating effects of technical flood protection measures. With its major outputs in form of novel probabilistic inundation and dike hazard maps, the IHAM system has a high practical value for decision support in flood management. N2 - Entlang eingedeichter Flussabschnitte kann das Hinterland ein hohes Schadenspotential, aufgrund der starken Akkumulation der Werte, aufweisen. Obwohl Deiche einen effizienten Schutz gegen kleinere häufiger auftretende Hochwässer bieten, können sie unter der Last hoher Wasserstände sowie langer Anstaudauer versagen. Gefährdungs- und Risikoabschätzungsmethoden für die eingedeichten Flussstrecken haben bisher die fluvialen Überflutungsprozesse nicht hinreichend berücksichtigt. Besonders, die Prozesse der Deichbrüche und deren Einfluss auf Überflutung im Hinterland und Fortschreiten der Hochwasserwelle verlangen eine umfassende Betrachtung. Die vorliegende Studie setzt ihren Fokus auf die Entwicklung und Anwendung eines neuen Modellierungssystems, das eine umfassende Hochwassergefährdungsanalyse entlang eingedeichter Flussstrecken unter Berücksichtigung von Deichbrüchen ermöglicht. Das vorgeschlagene Inundation Hazard Assessment Model (IHAM) stellt ein hybrides probabilistisch-deterministisches Modell dar. Es besteht aus drei laufzeitgekoppelten Modellen: (1) einem 1D instationären hydrodynamisch-numerischen Modell für den Flussschlauch und die Vorländer zwischen den Deichen, (2) einem probabilistischen Deichbruchmodell, welches die möglichen Bruchstellen, Breschenbreiten und Breschenausflüsse berechnet, und (3) einem 2D raster-basierten Überflutungsmodell für das Hinterland, das auf dem Speiherzellenansatz und der Diffusionswellengleichung basiert ist. Das probabilistische Deichbruchmodell beschreibt Deichbrüche, die infolge von drei Bruchmechanismen auftreten: dem Überströmen, dem Piping im Deichuntergrund und dem Versagen der landseitigen Böschung als Folge des Sickerflusses und der Erosion im Deichkörper (Mikro-Instabilität). Das 2D Speicherzellenmodell, angetrieben durch den Breschenausfluss als Randbedingung, berechnet ein erweitertes Spektrum der Hochwasserintensitätsindikatoren wie: Überflutungstiefe, Fliessgeschwindigkeit, Impuls, Überflutungsdauer und Wasseranstiegsrate. IHAM wird im Rahmen einer Monte Carlo Simulation ausgeführt und berücksichtigt die natürliche Variabilität der Hochwasserentstehungsprozesse, die in der Form der Hydrographen und deren Häufigkeit abgebildet wird, und die Zufälligkeit des Deichversagens, gegeben durch die Lokationen der Bruchstellen, der Zeitpunkte der Brüche und der Breschenbreiten. Das Modell wurde entwickelt und getestet an einem ca. 91 km langen Flussabschnitt. Dieser Flussabschnitt ist durchgängig eingedeicht und befindet sich an der deutschen Elbe zwischen den Pegeln Torgau und Vockerode. Die Szenarioberechnungen wurden von synthetischen Hydrographen für den Hauptstrom und Nebenfluss angetrieben, die für Hochwässer mit Wiederkehrintervallen von 100, 200, 500, und 1000 Jahren entwickelt wurden. Basierend auf den Modellierungsergebnissen wurden probabilistische Deichgefährdungskarten generiert. Sie zeigen die Versagenswahrscheinlichkeiten der diskretisierten Deichabschnitte für jede modellierte Hochwassermagnitude. Die Deichgefährdungskarten im disaggregierten Darstellungsmodus zeigen die Bruchwahrscheinlichkeiten für jeden betrachteten Bruchmechanismus. Neben den binären Überflutungsmustern, die die Wahrscheinlichkeit der Überflutung jeder Rasterzelle im Hinterland zeigen, generiert IHAM probabilistische Hochwassergefährdungskarten. Diese Karten stellen räumliche Muster der in Betracht gezogenen Hochwasserintensitätsindikatoren und entsprechende Jährlichkeiten dar. Schließlich, wurden mit IHAM Szenarien mit Aktivierung vom Polder bei extremen Hochwässern mit Jährlichkeiten von 200, 500, 1000 Jahren simuliert. Das entwickelte IHAM Modellierungssystem stellt ein neues wissenschaftliches Werkzeug für die Untersuchung fluvialer Überflutungsdynamik in extremen Hochwassersituationen unter Berücksichtigung des Einflusses technischer Hochwasserschutzmaßnahmen dar. Das IHAM System hat eine hohe praktische Bedeutung für die Entscheidungsunterstützung im Hochwassermanagement aufgrund der neuartigen Deichbruch- und Hochwassergefährdungskarten, die das Hauptprodukt der Simulationen darstellen. KW - Hochwasser KW - Deichbruch KW - Unsicherheitsanalyse KW - Gefährdungskarten KW - Polder KW - Flood KW - dike breach KW - uncertainty analysis KW - hazard maps KW - polder Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-27646 ER - TY - INPR A1 - Voss, Henning A1 - Kurths, Jürgen A1 - Schwarz, Udo T1 - Reconstruction of grand minima of solar activity from Delta 14 C data : linear and nonlinear signal analysis N2 - Using a special technique of data analysis, we have found out 34 grand minima of solar activity obtained from a 7,700 years long Δ14C record. The method used rests on a proper filtering of the Δ14C record and the extrapolation of verifiable results for the later history back in time. Additionally, we use a method of nonlinear dynamics, the recurrence rate, to back up the results. Our findings are not contradictory to the record of solar maxima resp. minima by Eddy [5], but constitute a considerable extension. Hence, it has become possible to look closer at the validity of models. This way, we have tested several models for solar activity, esp. the model of Barnes et al. [1]. There are hints for that the grand minima might solely be driven by the 209 year period found in the Δ14C record. T3 - NLD Preprints - 28 Y1 - 1996 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-14083 ER - TY - CHAP A1 - Votruba, V. A1 - Feldmeier, Achim A1 - Kubát, Jiří A1 - Rätzel, D. T1 - Multicomponent stellar wind of hot stars N2 - We developed a time-dependent multicomponent hydrodynamical code for simulation of the stellar wind from hot stars and applied it to stars with high and low density winds. Y1 - 2007 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-17677 ER - TY - GEN A1 - Wacker, Alexander A1 - von Elert, Eric T1 - Polyunsaturated fatty acids : evidence for non-substitutable biochemical resources in Daphnia galeata N2 - The factors that determine the efficiency of energy transfer in aquatic food webs have been investigated for many decades. The plant-animal interface is the most variable and least predictable of all levels in the food web. In order to study determinants of food quality in a large lake and to test the recently proposed central importance of the long-chained eicosapentaenoic acid (EPA) at the pelagic producer-grazer interface, we tested the importance of polyunsaturated fatty acids (PUFAs) at the pelagic producerconsumer interface by correlating sestonic food parameters with somatic growth rates of a clone of Daphnia galeata. Daphnia growth rates were obtained from standardized laboratory experiments spanning one season with Daphnia feeding on natural seston from Lake Constance, a large pre-alpine lake. Somatic growth rates were fitted to sestonic parameters by using a saturation function. A moderate amount of variation was explained when the model included the elemental parameters carbon (r2 = 0.6) and nitrogen (r2 = 0.71). A tighter fit was obtained when sestonic phosphorus was incorporated (r2 = 0.86). The nonlinear regression with EPA was relatively weak (r2 = 0.77), whereas the highest degree of variance was explained by three C18-PUFAs. The best (r2 = 0.95), and only significant, correlation of Daphnia's growth was found with the C18-PUFA α-linolenic acid (α-LA; C18:3n-3). This correlation was weakest in late August when C:P values increased to 300, suggesting that mineral and PUFA-limitation of Daphnia's growth changed seasonally. Sestonic phosphorus and some PUFAs showed not only tight correlations with growth, but also with sestonic α-LA content. We computed Monte Carlo simulations to test whether the observed effects of α-LA on growth could be accounted for by EPA, phosphorus, or one of the two C18-PUFAs, stearidonic acid (C18:4n-3) and linoleic acid (C18:2n-6). With >99 % probability, the correlation of growth with α-LA could not be explained by any of these parameters. In order to test for EPA limitation of Daphnia's growth, in parallel with experiments on pure seston, growth was determined on seston supplemented with chemostat-grown, P-limited Stephanodiscus hantzschii, which is rich in EPA. Although supplementation increased the EPA content 80-800x, no significant changes in the nonlinear regression of the growth rates with α-LA were found, indicating that growth of Daphnia on pure seston was not EPA limited. This indicates that the two fatty acids, EPA and α-LA, were not mutually substitutable biochemical resources and points to different physiological functions of these two PUFAs. These results support the PUFA-limitation hypothesis for sestonic C:P < 300 but are contrary to the hypothesis of a general importance of EPA, since no evidence for EPA limitation was found. It is suggested that the resource ratios of EPA and α-LA rather than the absolute concentrations determine which of the two resources is limiting growth. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 063 KW - alga KW - consumer KW - Daphnia KW - fatty acid KW - food quality KW - grazer KW - herbivore KW - Lake Constance KW - European Alps KW - PUFA KW - seston Y1 - 2001 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-17587 ER - TY - GEN A1 - Wacker, Alexander A1 - von Elert, Eric T1 - Strong influences of larval diet history on subsequent post-settlement growth in the freshwater mollusc Dreissena polymorpha N2 - Significant seasonal variation in size at settlement has been observed in newly settled larvae of Dreissena polymorpha in Lake Constance. Diet quality, which varies temporally and spatially in freshwater habitats, has been suggested as a significant factor influencing life history and development of freshwater invertebrates. Accordingly, experiments were conducted with field-collected larvae to test the hypothesis that diet quality can determine planktonic larval growth rates, size at settlement and subsequent post-metamorphic growth rates. Larvae were fed one of two diets or starved. One diet was composed of cyanobacterial cells which are deficient in polyunsaturated fatty acids (PUFAs), and the other was a mixed diet rich in PUFAs. Freshly metamorphosed animals from the starvation treatment had a carbon content per individual 70% lower than that of larvae fed the mixed diet. This apparent exhaustion of larval internal reserves resulted in a 50% reduction of the postmetamorphic growth rates. Growth was also reduced in animals previously fed the cyanobacterial diet. Hence, low food quantity or low food quality during the larval stage of D. polymorpha lead to irreversible effects for postmetamorphic animals, and is related to inferior competitive abilities. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 064 KW - Dreissena polymorpha KW - food quality KW - fatty acid KW - life history KW - metamorphosis KW - PUFA Y1 - 2002 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-17627 ER - TY - JOUR A1 - Wagner, Andreas T1 - Unity in diversity BT - integrating different linguistic data in TUSNELDA JF - Interdisciplinary studies on information structure : ISIS ; working papers of the SFB 632 N2 - This paper describes the creation and preparation of TUSNELDA, a collection of corpus data built for linguistic research. This collection contains a number of linguistically annotated corpora which differ in various aspects such as language, text sorts / data types, encoded annotation levels, and linguistic theories underlying the annotation. The paper focuses on this variation on the one hand and the way how these heterogeneous data are integrated into one resource on the other hand. Y1 - 2005 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-8625 SN - 1866-4725 SN - 1614-4708 IS - 2 SP - 1 EP - 20 ER - TY - THES A1 - Waha, Katharina T1 - Climate change impacts on agricultural vegetation in sub-Saharan Africa T1 - Auswirkungen von Klimaänderungen auf die landwirtschaftliche Vegetation in Afrika südlich der Sahara N2 - Agriculture is one of the most important human activities providing food and more agricultural goods for seven billion people around the world and is of special importance in sub-Saharan Africa. The majority of people depends on the agricultural sector for their livelihoods and will suffer from negative climate change impacts on agriculture until the middle and end of the 21st century, even more if weak governments, economic crises or violent conflicts endanger the countries’ food security. The impact of temperature increases and changing precipitation patterns on agricultural vegetation motivated this thesis in the first place. Analyzing the potentials of reducing negative climate change impacts by adapting crop management to changing climate is a second objective of the thesis. As a precondition for simulating climate change impacts on agricultural crops with a global crop model first the timing of sowing in the tropics was improved and validated as this is an important factor determining the length and timing of the crops´ development phases, the occurrence of water stress and final crop yield. Crop yields are projected to decline in most regions which is evident from the results of this thesis, but the uncertainties that exist in climate projections and in the efficiency of adaptation options because of political, economical or institutional obstacles have to be considered. The effect of temperature increases and changing precipitation patterns on crop yields can be analyzed separately and varies in space across the continent. Southern Africa is clearly the region most susceptible to climate change, especially to precipitation changes. The Sahel north of 13° N and parts of Eastern Africa with short growing seasons below 120 days and limited wet season precipitation of less than 500 mm are also vulnerable to precipitation changes while in most other part of East and Central Africa, in contrast, the effect of temperature increase on crops overbalances the precipitation effect and is most pronounced in a band stretching from Angola to Ethiopia in the 2060s. The results of this thesis confirm the findings from previous studies on the magnitude of climate change impact on crops in sub-Saharan Africa but beyond that helps to understand the drivers of these changes and the potential of certain management strategies for adaptation in more detail. Crop yield changes depend on the initial growing conditions, on the magnitude of climate change, and on the crop, cropping system and adaptive capacity of African farmers which is only now evident from this comprehensive study for sub-Saharan Africa. Furthermore this study improves the representation of tropical cropping systems in a global crop model and considers the major food crops cultivated in sub-Saharan Africa and climate change impacts throughout the continent. N2 - Landwirtschaft ist eine der wichtigsten menschlichen Aktivitäten, sie stellt Nahrungsmittel und andere landwirtschaftliche Produkte für weltweit 7 Milliarden Menschen zur Verfügung und ist in den Ländern Afrikas südlich der Sahara von besonderer Bedeutung. Die Mehrheit der afrikanischen Bevölkerung bestreitet ihren Lebensunterhalt in der Landwirtschaft und wird von Klimaänderungen stark betroffen sein. Die Doktorarbeit ist durch die Frage motiviert, wie sich von Klimamodellen vorhergesagte Temperaturerhöhungen und sich verändernde Niederschlagsverteilungen auf die landwirtschaftliche Vegetation auswirken werden. Die Forschungsfragen in diesem Kontext beschäftigen sich mit regionalen Unterschieden von Klimaänderungen und ihren Auswirkungen auf die Landwirtschaft und mit möglichen Anpassungsstrategien die mit geringem technischem Aufwand genutzt werden können. In diesem Zusammenhang wird schnell deutlich, dass Daten über die komplexen landwirtschaftlichen Systeme in Afrika südlich der Sahara häufig nur selten vorhanden sind, aus fragwürdigen Quellen stammen oder von schlechter Qualität sind. Die Methoden und Modelle zur Untersuchung der Auswirkungen von Klimaänderungen auf die Landwirtschaft werden zudem ausschließlich in Europa oder Nordamerika entwickelt and häufig in den temperierten Breiten aber seltener in tropischen Gebieten angewendet. Vor allem werden globale, dynamische Vegetationsmodelle in Kombination mit Klimamodellen eingesetzt um Änderungen in der landwirtschaftlichen Produktion auf Grund von Klimaänderungen in der zweiten Hälfte des 21.Jahrhunderts abzuschätzen. Die Ergebnisse der Arbeit zeigen einen mittleren Ertragsrückgang für die wichtigsten landwirtschaftlichen Pflanzen um 6% bis 24% bis 2090 je nach Region, Klimamodell und Anpassungsstrategie. Dieses Ergebnis macht deutlich, dass Landwirte die negativen Folgen von Klimaänderungen abschwächen können, wenn sie die Wahl der Feldfrucht, die Wahl des Anbausystems und den Aussaattermin an geänderte Klimabedingungen anpassen. Die Arbeit stellt methodische Ansätze zur Berechung des Aussaattermins in temperierten und tropischen Gebieten (Kapitel 2) sowie zur Simulation von Mehrfachanbausystemen in den Tropen vor (Kapitel 3). Dabei werden wichtige Parameter für das globale, dynamische Vegetationsmodell LPJmL überprüft und neu berechnet. Es zeigt sich, dass das südliche Afrika und die Sahelregion die am stärksten betroffenen Regionen sind, vor allem aufgrund von Niederschlagsänderungen, weniger aufgrund von Temperaturerhöhungen. In den meisten anderen Teilen, vor allem Zentral- und Ostafrikas bedingen Temperaturerhöhungen Rückgänge der Erträge (Kapitel 4). Diese Arbeit leistet einen wichtigen und umfassenden Beitrag zum Verständnis der Auswirkung von Klimaänderung auf die landwirtschaftliche Vegetation und damit zu einem großen Teil auf die Lebensgrundlage von afrikanischen Landwirten. KW - Klimawandel KW - Anpassung KW - Afrika KW - Pflanzenwachstum KW - Landwirtschaft KW - climate change KW - Africa KW - crop modeling KW - adapation KW - agriculture Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-64717 ER - TY - JOUR A1 - Wallach, Kerry T1 - Isabella Gartner: Menorah : Jüdisches Familienblatt für Wissenschaft, Kunst und Literatur (1923–1932) ; Materialien zur Geschichte einer Wiener zionistischen Zeitschrift / [rezensiert von] Kerry Wallach JF - PaRDeS : Zeitschrift der Vereinigung für Jüdische Studien e.V. N2 - rezensiertes Werk: Gartner, Isabella: Menorah : Jüdisches Familienblatt für Wissenschaft, Kunst und Literatur (1923–1932) ; Materialien zur Geschichte einer Wiener zionistischen Zeitschrift. - Würzburg : Königshausen & Neumann, 2009. - 356 S. ISBN 978-3-8260-3864-8 Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-43715 SN - 1614-6492 SN - 1862-7684 IS - 16 SP - 226 EP - 229 ER - TY - JOUR A1 - Walsh, J. R. A1 - Monreal-Ibero, A. A1 - Vílchez, J. M. A1 - Pérez-Montero, E. A1 - Iglesias-Páramo, J. A1 - Sandin, C. A1 - Relano, M. A1 - Amorín, R. T1 - The Wolf-Rayet Population and ISM Interaction in Nearby Starbursts JF - Wolf-Rayet Stars : Proceedings of an International Workshop held in Potsdam, Germany, 1.–5. June 2015 N2 - The interaction between massive star formation and gas is a key ingredient in galaxy evolution. Given the level of observational detail currently achievable in nearby starbursts, they constitute ideal laboratories to study interaction process that contribute to global evolution in all types of galaxies. Wolf-Rayet (WR) stars, as an observational marker of high mass star formation, play a pivotal role and their winds can strongly influence the surrounding gas. Imaging spectroscopy of two nearby (<4 Mpc) starbursts, both of which show multiple regions with WR stars, are discussed. The relation between the WR content and the physical and chemical properties of the surrounding ionized gas is explored. Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-88339 SP - 341 EP - 344 ER - TY - CHAP A1 - Walter, R. A1 - Zurita-Heras, J. A1 - Leyder, J.-C. T1 - Probing clumpy stellar winds with a neutron star N2 - INTEGRAL tripled the number of super-giant high-mass X-ray binaries (sgHMXB) known in the Galaxy by revealing absorbed and fast transient (SFXT) systems. Quantitative constraints on the wind clumping of massive stars can be obtained from the study of the hard X-ray variability of SFXT. A large fraction of the hard X-ray emission is emitted in the form of flares with a typical duration of 3 ksec, frequency of 7 days and luminosity of $10^{36}$ erg/s. Such flares are most probably emitted by the interaction of a compact object orbiting at $\sim10~R_*$ with wind clumps ($10^{22 ... 23}$ g) representing a large fraction of the stellar mass-loss rate. The density ratio between the clumps and the inter-clump medium is $10^{2 ... 4}$. The parameters of the clumps and of the inter-clump medium, derived from the SFXT flaring behavior, are in good agreement with macro-clumping scenario and line-driven instability simulations. SFXT are likely to have larger orbital radius than classical sgHMXB. Y1 - 2007 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-18024 ER - TY - JOUR A1 - Walz, Steffen P. T1 - Approaches to space in game design research JF - DIGAREC Lectures 2008/09 : Vorträge am Zentrum für Computerspielforschung mit Wissenschaftsforum der Deutschen Gamestage ; Quo Vadis 2008 und 2009 N2 - In this contribution, we gather major academic and design approaches for explaining how space in games is constructed and how it constructs games, thereby defining the conceptual dimensions of gamespace. Each concept’s major inquiry is briefly discussed, iterated if applicable, as well as named. Thus, we conclude with an overview of the locative, the representational, the programmatic, the dramaturgical, the typological, the perspectivistic, the form-functional, and the form-emotive dimensions. Y1 - 2009 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-33259 SN - 978-3-86956-004-5 SN - 1867-6219 IS - 2 SP - 228 EP - 254 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - GEN A1 - Ward, Colleen A1 - Newlon, Betty A1 - Krahé, Barbara A1 - Myambo, Kathleen A1 - Payne, Monica A1 - Tastaban, Yildiz A1 - Yuksel, Sahika A1 - Ghadially, Rehana A1 - Kumar, Usha A1 - Lee, Hing-chu B A1 - Cheung, Fanny M. A1 - Upadhyaya, Shirpati A1 - Patnoe, Jerry A1 - Kirby, Carol A1 - Gomez, Antonio Vasquez A1 - Parra, Elena A1 - Colosio, Laura T1 - The attitudes toward rape victims scale : psychometric data from 14 countries N2 - Content: Synopsis The Attitudes toward Rape Victims Scale: Psychometric Data from 14 Countries Scale Construction and Validation - Study One: Preliminary Analyses - Study Two: Test-Retest Reliability - Study Three: Construct Validity Cross-cultural Extensions - United States - United Kingdom - Germany - New Zealand - Canada - West Indies - Israel - Turkey - India - Hong Kong - Malaysia - Zimbabwe - Mexico - Metric Equivalence Discussion T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - paper 085 Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-34495 ER -