Holocene fluctuations of neodymium isotope ratios in eastern Fram Strait sediments - An indication for deepwater variability?

EGU2012-11739 The Fram Strait as the only deep water connection of the world’s oceans to the Arctic plays a substantial role for the heat influx to the Arctic Ocean and controls freshening of the Nordic Seas through Arctic sea ice export. Large amounts of warm and saline Atlantic Water derived from the North Atlantic Drift transport most of the heat through eastern Fram Strait to the Arctic basin, resulting in year-round ice-free conditions. Arctic sea ice and cold and fresh waters exit the western part of the strait southward along the Greenland shelf. However, little is still known about the water mass transport at intermediate and bottom water depths in the Fram Strait. High-resolution Holocene sediment sequences from the Western Svalbard margin have been investigated for its neodymium isotope ratios stored in ferromanganese oxyhydroxide coatings of the sediment to derive information on the source of bottom seawater passing the site. The radiogenic isotope data are compared to a multitude of proxy indicators for the climatic and oceanographic variability in the eastern Fram Strait during the past 8,500 years. In order to obtain a calibration of the Nd isotope compositions extracted from sediments to modern bottom water mass signatures in the area, a set of core top and water samples from different water depths in the Fram Strait was additionally investigated for its present-day Nd isotope signatures. A significantly higher inflow of deepwater produced in the Nordic Seas to the core site is inferred for the earlier periods of the Holocene. Cooler surface water conditions and increased sea ice abundances during the late Holocene coincide with more radiogenic Nd isotope ratios likely resembling the neoglacial trend of the northern North Atlantic

Hasard et destin dans le Anton Reiser de Karl Philipp Moritz

International audienceThe distinction between literary chance and chance as experience (E. Köhler) allows the originality of Moritz's autobiographical novel to be disengaged. This study of the motif of chance in book II ofAnton Reiser shows the establishment of a narrative method characterized by repressing the literary treatment of chance and maintaining of chance as a category of lived experience. In this text, the fortunate and unfortunate chances do not found the literary necessity of an exemplary destiny, but are the occasion for throwing light on the double determination, exterior and interior, that affects the character's existence, an existence that is experienced under the sign of a radical contingency. It is in this first obscurity that psychological analysis operates, not to establish the horizon of Providence, but to disengage the general lessons of an existence, and to give to its hero, at this moment, the consistency of a novelistic character.La distinction entre les deux catégories du « hasard vécu » (erlebter Zufall) et du « hasard littéraire » (literarischer Zufall), empruntée à Erich Köhler, permet d'aborder l'étude du roman autobiographique de Karl Philipp Moritz, Anton Reiser, en faisant ressortir l'ambivalence d'un projet "romanesque" en un sens nouveau. On montre ici comment le recul de la figuration du hasard littéraire au profit de la figuration du hasard vécu exprime la remise en cause du roman traditionnel et la recherche de nouvelles formes permettant de saisir et de donner forme à la consistance de la vie intérieure

Bidirectional flow measurement based on the differential pressure method for surge analysis on a small centrifugal compressor

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.To obtain a high temporal resolution of mass flow data, a flowmeter based on the differential pressure method has been developed. It is capable of detecting negative flow for investigations of dynamic effects in small centrifugal compressors used for turbocharging automotive internal combustion engines. Experiments were performed at a hot gas test bench focusing on the surge characteristics at different turbocharger speeds and the influence of volume modifications downstream of the compressor. Instantaneous operating points could be traced in the compressor map including the typical orbits at deep surge resulting from the cyclic character of the phenomenon

Time to go beyond interstate federalism - or something different? The response of new pro-European think tanks to the EU integration crisis

The European financial and economic crisis has shaken traditional beliefs and confidence in a one-directional move towards an ever closer union. Discussions regarding "Grexit" and the public vote in favor of "Brexit" have signaled strong anti-EU sentiment far beyond previous instances of dissatisfaction expressed by popular votes in France and the Netherlands opposing the European constitution, for example. Mainstream European integration scholars have started to seriously address disintegration theory; once a preserve of Marxist critiques of mainstream integration scholarship. European right-wing parties, foundations and think tanks openly advocate (partial) disintegration and, in particular, aim to interrupt centrist Social Democratic, Green, Liberal and Conservative cooperation in the European Parliament. What has been the response to these conceptual and political challenges from the pro-European political forces in European politics? In the shadow of Syriza's anti-austerity campaign from Greece and Podemos' grassroots mobilization in Spain, a range of new pro-European think tanks of different political-philosophical leanings have been founded after the crisis, or developed new activities in response to the crisis. The paper will examine the publications of organizations like European Alternatives, Project for a Democratic Europe and EuropaNova in order to observe if and how a new cross-cutting network of pro-European intellectuals, think tanks and ideas address the present crisis, and if and in which ways we can speak of new conceptual and political approaches to European integration that promise innovation and progressive (in the sense of pro-European integration) learning. Do they look beyond neoliberal restrictions to Europe's "sui generis" Union (Hayek's version of interstate federalism), something closer to real (fiscal) federalism - or something different? We will also examine if and how they differ from more centrist institutional efforts to envision the future, such as those uttered by Commission officials, MEPs of the Spinelli-Group, or experts like those assembled in the Glienicker Group. Last, but not least, we will try to establish if and to what extent new conceptual efforts reverberate in pro-European integration debating platforms like Publixphere, OneEurope or Krytyka Polityczna (Political Critique), which are considered more likely echo chambers for pro-European integration think tanks than mainstream media.Die europäische Finanz- und Wirtschaftskrise hat traditionelle Vorstellungen bezüglich der europäischen Integration und das Vertrauen in die Entwicklung in Richtung einer immer engeren Union erschüttert. Diskussionen über den "Grexit" und das Votum für den "Brexit" haben starke anti-europäische Stimmungen erkennen lassen, die weit über bisherige Unzufriedenheit, wie sie z.B. bei Volksabstimmungen in Frankreich und den Niederlanden gegen die europäische Verfassung zum Ausdruck kamen, hinausreichen. Der Mainstream Europäischer Integrationsforschung hat ernsthaft damit begonnen, Auflösungstheorien zu thematisieren, einst eine Domäne marxistischer Kritik an der etablierten Integrationsforschung. Rechtsgerichtete europäische Parteien, Stiftungen und Think-Tanks befürworten offen einen teilweisen Rückbau und beabsichtigen insbesondere, die Zusammenarbeit von gemäßigten Sozialdemokraten, Grünen, Liberalen und Konservativen im Europäischen Parlament zu beenden. Welche Antworten geben pro-europäische politische Kräfte in der europäischen Politik auf diese konzeptionellen und politischen Herausforderungen? Im Schatten der Syriza-Kampagne gegen die Sparpolitik in Griechenland und der Mobilisierung durch Podemos in Spanien wurden nach der Krise eine Reihe pro-europäischer Think-Tanks verschiedener politisch-ideologischer Ausrichtung gegründet oder haben neue Aktivitäten als Reaktion auf die Krise entwickelt. Der Beitrag untersucht die Publikationen von Organisationen wie European Alternatives, Project for a Democratic Europe und EuropaNova um festzustellen, ob und wie ein neues, übergreifendes Netzwerk pro-europäischer Intellektueller, Think-Tanks und Ideen die gegenwärtige Krise thematisiert. Dabei wird insbesondere gefragt, ob und in welcher Weise von neuen konzeptionellen und politischen Ansätzen zur europäischen Integration gesprochen werden kann, die Innovation und fortschrittliches Lernen (im Sinne von pro-europäischer Integration) versprechen. Gehen Beiträge über die neoliberalen Restriktionen der Europäischen "sui generis" Union hinaus (Hayeks Variante eines zwischenstaatlichen Föderalismus), etwa in Annäherung an europäischen (fiskalischen) Föderalismus - oder etwas anderes? Zur Einordnung der Beiträge der Think-Tanks werden diese mit Aussagen zur Zukunft der EU aus Studien im Kontext der europäischen Institutionen abgeglichen, darunter Beiträge von Kommissionsbeamten, Abgeordneten der Spinelli-Gruppe zur Arbeit des Europäischen Parlamentes sowie Fachleuten und Beratern z.B. der Glienicker Gruppe. Last but not least wird versucht zu ermitteln, ob und inwieweit sich die konzeptionelle Arbeit der Think-Tanks in pro-europäischen Diskussionsplattformen wie Publixphere, OneEurope oder Krytyka Polityczna (Political Critique) niederschlägt oder spiegelt. Diese kommen stärker als etwa nationale Printmedien als mögliche Echokammern der pro-europäischen Think-Tanks in Frage, weil Autorinnen und Autoren sowie Leser und Leserinnen als generell europainteressiert gelten können

First Quantification of the Permafrost Heat Sink in the Earth's Climate System

Due to an imbalance between incoming and outgoing radiation at the top of the atmosphere, excess heat has accumulated in Earth's climate system in recent decades, driving global warming and climatic changes. To date, it has not been quantified how much of this excess heat is used to melt ground ice in permafrost. Here, we diagnose changes in sensible and latent ground heat contents in the northern terrestrial permafrost region from ensemble-simulations of a tailored land surface model. We find that between 1980 and 2018, about 3.9^+1.4_-1.6 ZJ of heat, of which 1.7_-1.4^+1.3 ZJ (44%) were used to melt ground ice, were absorbed by permafrost. Our estimate, which does not yet account for the potentially increased heat uptake due to thermokarst processes in ice-rich terrain, suggests that permafrost is a persistent heat sink comparable in magnitude to other components of the cryosphere and must be explicitly considered when assessing Earth's energy imbalance.Bundesministerium für Bildung und Forschung http://dx.doi.org/10.13039/501100002347Peer Reviewe

Study of the particle formation and morphology of single mannitol-water droplets depending on the drying conditions

In chemical, pharmaceutical and food processing industry, spray processes have a wide range of applications, especially in the production of tailor-made powder products of defined characteristics from solutions or suspensions. The effects of process parameters (e.g. temperature and relative humidity) on the drying kinetic of a droplet and the properties of the resulting particles are largely based on experience. Still there is a lack of information on the fundamentals of particle formation. To close this gap numerical simulations as well as single droplet experiments were carried out under various conditions. This study concerns the influences of relative humidity, drying temperature and mass fraction on the solid layer formation and on the particles of single droplets consisting of mannitol-water solutions. An acoustic levitator (Fig 1 a)) was used to carry out the single droplet experiments. By means of a camera and a light source shadowgraphy was used to analyze the droplet drying kinetic and the development of the droplet respectively. Raman spectroscopy was used to analyze the polymorphism[1] of oversaturated mannitol-water droplets (relative humidity above 10 %). Using a thin thermocouple (150 µm) the particle temperature was recorded. Typical drying curves showed a continuous decrease of the droplet surface area until the solid layer was formed. The progress of the droplet temperature during the evaporation depends on the increase of the mannitol concentration at the droplet surface and start crystallization. Numerically, the unsteady, one-dimensional mass and energy diffusion equations for spherically symmetric droplets were solved accounting for the occurrence of the solid layer formation. Moreover, the influence of the air humidity on the solid layer formation and the droplet temperature evolution was investigated experimentally and validated by simulations. It was shown that an increase in the humidity of the drying air leads to a delayed solid layer formation[2] and a decrease of the final particle porosity whereas a higher mannitol concentration and a higher temperature have a contrary effect. The validity of the numerical model concerning the time instance of the solid layer formation and the progress of the droplet temperature was confirmed. Using the numerical model the drying of a single droplet was successfully simulated. Additionally a morphology map for the obtained particles from the single droplet experiments was developed. Please click Additional Files below to see the full abstract

Psychopathological Course Typology in Schizophrenia Spectrum Disorders: A Heuristic Approach in a Sample of 100 Patients

Background: Despite several previous attempts at subtyping schizophrenia, a typology that reflects neurobiological knowledge and reliably predicts course and outcome is lacking. We applied the system-specific concept of the Bern Psychopathology Scale (BPS) to generate a course typology based on three domains: language, affectivity, and motor behaviour. Sampling and Methods: A cohort of 100 patients with schizophrenia or schizoaffective disorders according to DSM-IV criteria underwent psychopathological assessment, and all their available medical records were retrospectively analysed on the basis of the BPS. Results: Overall, 39% of the patients showed dominant abnormalities in only one domain, 37% in two domains, and 24% in all three domains. The motor domain was affected in the majority of patients (76%), followed by affectivity (63%) and language (46%). Eighty-six percent of patients showed a bipolar course pattern in at least one domain. Conclusions: In a retrospective analysis of 100 patient records we described system-specific course patterns of schizophrenia by using a neurobiologically informed psychopathological assessment. The results showed a surprisingly high proportion of bipolar courses and a pattern of pure and mixed subtypes, which speaks for an overlap of domains with regards to psychopathological symptoms. A limitation of this heuristic and retrospective approach is that it was largely based on clinical judgement. Prospective studies with more rigorous threshold definitions are needed to clarify the neurobiological and clinical implications of the proposed reorganization of psychotic disorders. (C) 2016 S. Karger AG, Base

Towards 3D Process Simulation for In-Situ Hybridization of Fiber-Metal-Laminates (FML)

Fiber-metal-laminates (FML) provide excellent fatigue behavior, damage tolerant properties, and inherent corrosion resistance.To speed up manufacturing and simultaneously increase the geometrical complexity of the produced FML parts, Mennecart et al. proposed a new single-step process combining deep-drawing with infiltration (HY-LCM). Although the first experimental results are promising, the process involves several challenges, mainly originating from the Fluid-Structure-Interaction (FSI) between deep-drawing and infiltration. This work aims to investigate those challenges to comprehend the underlying mechanisms. A new close-to-process test setup is proposed on the experimental side, combining deep-drawing of a hybrid stack with a linear infiltration. A process simulation model for FMLs is presented on the numerical side, enabling a prediction of the dry molding forces, local Fiber Volume Content (FVC) within the three glass fiber (GF) interlayers, and simultaneous fluid progression. The numerical results show that the local deformation of the hybrid stack and required forces are predictable. Furthermore, lateral sealing of the hybrid stacks leads to deviations from the intended initially one-dimensional fluid progression. Eventually, the numerical results demonstrate that most flow resistance originates from geometrically critical locations. Future experimental and numerical work will combine these insights to focus on the flow evaluation during deformation and a successful part-level application