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In this paper, we examine how the institutional design affects the outcome of bank bailout decisions. In the German savings bank sector, distress events can be resolved by local politicians or a state-level association. We show that decisions by local politicians with close links to the bank are distorted by personal considerations: While distress events per se are not related to the electoral cycle, the probability of local politicians injecting taxpayers’ money into a bank in distress is 30 percent lower in the year directly preceding an election. Using the electoral cycle as an instrument, we show that banks that are bailed out by local politicians experience less restructuring and perform considerably worse than banks that are supported by the savings bank association. Our findings illustrate that larger distance between banks and decision makers reduces distortions in the decision making process, which has implications for the design of bank regulation and supervision.
Against the background of the European debt crisis, the Research Center SAFE, in the fall of 2013, had issued a call for papers on the topic “Austerity and Economic Growth: Concepts for Europe”, with the objective of soliciting research proposals focusing on the nature of the relationship between austerity, debt sustainability and growth. Each of the five funded projects brought forth an academic paper and a shortened, non-technical policy brief. These policy papers are presented in the present collection of policy letters, edited by Alfons Weichenrieder.
The first paper by Alberto Alesina, Carlo Favero and Francesco Giavazzi looks into the question of how fiscal consolidations influence the real economy. Harris Dellas and Dirk Niepelt emphasize that fiscal austerity is a signal that investors use to tell apart governments with high and low default costs that accordingly will have a high or low probability of repayment.The paper by Benjamin Born, Gernot Müller and Johannes Pfeiffer,looks at the impact of austerity measures on government bond spreads. Oscar Jorda and Alan M. Taylor, in the fourth contribution, put into question whether the narrative records of fiscal consolidation plans are really exogenous. The final study by Enrique Mendoza, Linda Tesar and Jing Zhang suggests that fiscal consolidation should largely depend on expenditure cuts, rather than tax increases that may fail, when fiscal space is exhausted.
Spätestens seit die Europäische Zentralbank (EZB) ihr Ankaufprogramm für Wertpapiere bekannt gegeben hat, ist die Diskussion über die Wirksamkeit dieser Maßnahmen auch in Europa angekommen. Wegen der besonderen institutionellen Umstände des Euroraums – Kauf von Anleihen der einzelnen Nationalstaaten und des Verbots der monetären Finanzierung – reichen die möglichen Nebenwirkungen hierzulande über den rein geldpolitischen Horizont hinaus.
Regulatory failures, which came to the fore after the financial crisis of 2007-2009, lead to the question of why some activities by financial institutions were not regulated prior to the crisis of 2007, even though regulators knew about certain dangers to financial stability? The repo-market, although centrally involved in the last crisis, still awaits stringent regulation. At the same time, the regulatory cycle seems to come to an end, boding ill for future crises which will be amplified by this market. In this situation, NGOs are needed to make regulators act upon their knowledge and to tighten their regulations.
Greece: threatening recovery
(2015)
Despite the catastrophic phase between 2008 and the end of 2014, much of a previously unsustainable development has been corrected in Greece and there are clear signs that the deterioration came to a halt in 2014. But what is publicly known about the priorities of the newly elected Syriza government suggests that they may be going largely into the wrong direction.
This paper investigates whether a fiscal stimulus implies a different impact for flexible and rigid labour markets. The analysis is done for 11 advanced OECD economies. Using quarterly data from 1999 to 2013, I estimate a panel threshold structural VAR model in which regime switches are determined by OECD’s employment protection legislation index. My empirical results indicate significant differences between rigid and flexible labour markets regarding the impact of the fiscal stimulus on output and unemployment. While the impulse response of real GDP to a government spending shock is positive and more effective in flexible labour markets, it has less impact in the rigid ones. Moreover, it is found that a fiscal stimulus leads to higher overall unemployment in highly regulated countries.
Does exchange of information between tax authorities influence multinationals' use of tax havens?
(2015)
Since the mid-1990s, countries offering tax systems that facilitate international tax avoidance and evasion have been facing growing political pressure to comply with the internationally agreed standards of exchange of tax information. Using data of German investments in tax havens, we find evidence that the conclusion of a bilateral tax information exchange agreement (TIEA) is associated with fewer operations in tax havens and the number of German affiliates has on average decreased by 46% compared to a control group. This suggests that firms invest in tax havens not only for their low tax rates but also for the secrecy they offer.
Most recent regulations establish that resolution of global banking groups shall be done according to bail-in procedures and following a Single Point of Entry (SPE) as opposed to a Multiple Point of Entry (MPE) approach. The latter requires parent holding of global groups to put up front the equity capital needed to absorb losses possibly emerging in foreign subsidiaries-branches. No model rationalized so far such resolution regime. We build a model of optimal design of resolution regimes and compare three regimes: SPE with cooperative authorities, SPE with non-cooperative authorities and MPE (ring-fencing). We find that the costs for bondholders of bail-inable instruments is generally higher under noncooperative regimes and ring-fencing. We also find that in those cases banks have ex ante incentives to reduce their exposure in foreign assets. We also examine recent case studies that help us rationalize the model results.
We present a network model of the interbank market in which optimizing risk averse banks lend to each other and invest in non-liquid assets. Market clearing takes place through a tâtonnement process which yields the equilibrium price, while traded quantities are determined by means of a matching algorithm. We compare three alternative matching algorithms: maximum entropy, closest matching and random matching. Contagion occurs through liquidity hoarding, interbank interlinkages and fire sale externalities. The resulting network configurations exhibits a core-periphery structure, dis-assortative behavior and low clustering coefficient. We measure systemic importance by means of network centrality and input-output metrics and the contribution of systemic risk by means of Shapley values. Within this framework we analyze the effects of prudential policies on the stability/efficiency trade-off. Liquidity requirements unequivocally decrease systemic risk but at the cost of lower efficiency (measured by aggregate investment in non-liquid assets); equity requirements tend to reduce risk (hence increase stability) without reducing significantly overall investment.
Based on a sample of university students, we provide field and laboratory evidence that a small scale training intervention has a both statistically and economically significant effect on subjective and objective assessments of financial knowledge. We also show that for a large part of students whose self-assessed financial knowledge has improved we do not find an increase in their actual skills.
We set up and solve a rich life-cycle model of household decisions involving consumption of both perishable goods and housing services, stochastic and unspanned labor income, stochastic house prices, home renting and owning, stock investments, and portfolio constraints. The model features habit formation for housing consumption, which leads to optimal decisions closer in line with empirical observations. Our model can explain (i) that stock investments are low or zero for many young agents and then gradually increasing over life, (ii) that the housing expenditure share is age- and wealth-dependent, (iii) that perishable consumption is more sensitive to wealth and income shocks than housing consumption, and (iv) that non-housing consumption is hump-shaped over life.
This paper investigates whether exchanging the Social Security delayed retirement credit, currently paid as an increase in lifetime annuity benefits, for a lump sum would induce later claiming and additional work. We show that people would voluntarily claim about half a year later if the lump sum were paid for claiming any time after the Early Retirement Age, and about two-thirds of a year later if the lump sum were paid only for those claiming after their Full Retirement Age. Overall, people will work one-third to one-half of the additional months, compared to the status quo. Those who would currently claim at the youngest ages are likely to be most responsive to the offer of a lump sum benefit.
Traditional least squares estimates of the responsiveness of gasoline consumption to changes in gasoline prices are biased toward zero, given the endogeneity of gasoline prices. A seemingly natural solution to this problem is to instrument for gasoline prices using gasoline taxes, but this approach tends to yield implausibly large price elasticities. We demonstrate that anticipatory behavior provides an important explanation for this result. We provide evidence that gasoline buyers increase gasoline purchases before tax increases and delay gasoline purchases before tax decreases. This intertemporal substitution renders the tax instrument endogenous, invalidating conventional IV analysis. We show that including suitable leads and lags in the regression restores the validity of the IV estimator, resulting in much lower and more plausible elasticity estimates. Our analysis has implications more broadly for the IV analysis of markets in which buyers may store purchases for future consumption.
Klimaschutz- und Anpassungsmaßnahmen : Zielkonflikte und Synergien mit dem Biodiversitätsschutz
(2015)
Der Klimawandel ist eine der größten Herausforderungen der Gegenwart und seine Auswirkungen auf Natur, Gesellschaft und Wirtschaft werden vielfach untersucht. Minderungs- wie auch Anpassungsmaßnahmen sind somit ein wichtiges Handlungsfeld geworden. Während der Einfluss des Klimawandels auf die Biodiversität bereits seit Längerem Gegenstand wissenschaftlicher Untersuchungen ist, rücken nun auch mögliche Folgen von Klimaschutz- und Anpassungsmaßnahmen auf die biologische Vielfalt in den Fokus der Forschung: So ist eine generelle Treibhausgasreduktion zwar prinzipiell förderlich, jedoch kann die Umsetzung der hierfür notwendigen Maßnahmen zu Zielkonflikten mit dem Biodiversitätsschutz führen. Gleichwohl gibt es Herangehensweisen, die Synergien beider Bereiche erkennen lassen.
Das Papier bietet einen Überblick über Maßnahmen des Klimaschutzes und der Klimawandelanpassung in den Bereichen Wald- und Forstwirtschaft, Moore, Landwirtschaft, nachwachsende Rohstoffe, Fließgewässer, Küsten und Meere. Diese werden mit Blick auf ihre möglichen (sowohl förderlichen als auch abträglichen) Auswirkungen auf die Biodiversität vorgestellt. Mit dieser problemorientierten Diskursfeldanalyse soll ein Beitrag geleistet werden, potentielle Zielkonflikte von Klima- und Biodiversitätsschutz zu erkennen und Synergien zu fördern.
In der Netzschau dieser Woche geht es um afghanischen Aktivismus für Frauenrechte, Joseph Blatters opportunistische Thematisierung von Diskriminierung von Frauen im Iran, die Wirksamkeit von Mikrokrediten, den Islamischen Staat und die Probleme des Nahen und Mittleren Ostens und die Überwachung durch die NSA.
Last week, this year’s ISA conference brought together over 5000 scholars and exhibitors from all over the world to discuss all things international, political, scholarly, hold meetings, get lunch together, and party at Mardi Gras (it was in New Orleans, after all!). Similar to last year, a lot of this discussing took also place on Twitter. Scholars-slash-tweeps rallied around the hashtag #isa2015 to talk to each other online about great (and not so great) panels, trends in IR scholarship, gender bias in academia, and (not surprisingly for an academic conference) coffee. Who was most active during ISA2015 on Twitter? What were the most hotly debated topics online? When did ISAlers tweet?
Ein Crosspost aus dem äußerst lesenswerten neuen Blog der Friedensakademie Rheinland-Pfalz friedensakademie-blog.eu/ zur aktuellen Lage in Libyen: Dort droht die internationale Staatengemeinschaft vier Jahre nach der Intervention in ihrer Verantwortung zur Prävention eines weiteren Blutvergießens zu scheitern. Mein Originalbeitrag beim Friedensakademie-Blog erschien am 6. Februar 2015.
Barriereinseln und Nehrungshaken, geformt durch eine Kombination aus Wind, Wellen, Strömung und Küstenlängstransport gelten als geologisch junge und morphologisch hoch aktive Küstenbereiche und variieren häufig in Ursprung, Genese und Entwicklung. Bisherige Untersuchungen zur Stratigraphie dieser durch engräumige Fazieswechsel geprägten Sedimentationsräume basieren häufig allein auf Bohrungen. Daher sind die interne sedimentologische Struktur und die Prozesse, die zur Entwicklung von Barriereinseln und Nehrungshaken geführt haben, oftmals unzureichend untersucht.
Ziel der folgenden Studie war es, anhand hochauflösender Georadarmessungen (GPR) und Bohrungen die Entstehung und interne sedimentäre Architektur der Nehrungshaken von Sylt und Amrum zu rekonstruieren. Durch die Korrelation von Sediment- und Radarfazies konnten über den bisherigen Kenntnisstand hinaus wertvolle, sich ergänzende Informationen zur Geologie des oberflächennahen Untergrundes der Inseln Sylt und Amrum gewonnen werden. Auf dieser Grundlage wurden für den Süden Sylts, die Westküste von Amrum und den Norden Amrums stratigraphische Modelle entwickelt, die schematisch den sedimentologischen Aufbau, die geomorphologisch-geologische Genese und die am Aufbau beteiligten Prozesse zusammenfassen. Die Einordnung in einen absoluten Zeitrahmen wurde durch Datierungen (AMS Radiokohlenstoff-Methode, Aminosäure-Racemisierungs-Methode) ermöglicht.
Die Ergebnisse sind als Beispiel für die Heterogenität und Individualität von Nehrungshaken und Barriereinseln zu sehen. Es konnte gezeigt werden, dass Nehrungshaken hinsichtlich ihres Aufbaus, ihrer sedimentären Struktur sowie den Prozessen ihrer Entstehung sehr unterschiedlich sind.
Mit Ausnahme der heutigen Dünen zeigt die Stratigraphie der Ansatzzone des südlichen Nehrungshakens von Sylt an den zentralen Inselgeestkern südlich der Ortschaft Rantum insgesamt eine Vergröberungs-Sequenz von tonigem Mischwatt im Liegenden über Sandwatt bis zu den gröberen washover-Schichten im Hangenden. Eine Besonderheit und regionale Abweichung stellt die Stratigraphie bei Puan Klent/Thörnhörn dar. Dort wurde im Liegenden der Watt-Fazies ein fossiler Strandhaken nachgewiesen.
Die transgressive Sequenz der Ansatzzone des südlichen Nehrungshakens von Sylt bei Rantum auf Sylt ist kennzeichnend für eine landwärts gerichtete Wanderungsbewegung der Inselbarriere unter steigendem Meeresspiegel. Das Resultat des als „barrier rollover“ bezeichneten morphologischen Prozesses ist die allmähliche Erosion der westlichen Barrierefront. Das erodierte Sediment der Westküste wurde entweder durch overwash-Prozesse im rückwärtigen Inselbereich als washover fan abgelagert oder gelangte in den Küstenlängstransport, wurde zur Inselspitze transportiert und dort akkumuliert. Diese führte allmählich zum Wachstum und zur Progradation der südlichen Inselspitze (Hörnum Odde) in die sich südlich anschließende Tiderinne des Hörnum-Tiefs. Zahlreiche Erosionsdiskordanzen unterhalb des heutigen Meeresspiegels markieren ursprüngliche Inselspitzenendpositionen (time lines) und sind auf hochenergetische Sturmflutereignisse zurückzuführen. Die time lines werden nach Süden hin jünger und zeichnen unterschiedliche Stadien der Progradation nach, die ein episodisches Wachstum der Inselspitze in Abhängigkeit von der Sedimentverfügbarkeit und der Sturmflutintensität belegen. Alte Erosionsdiskordanzen belegen die frühe submarine Genese der Hörnum Odde. Ein starkes Wachstum der südlichen Inselspitze Sylts lässt sich im Mittelalter nachweisen.
Sturmfluten führten zudem immer wieder zu overwash-Prozessen und Überschwemmungen der noch jungen Inselspitze. Dies belegen ältere washover-Ablagerungen, die in unterschiedlichen Phasen der Nehrungshakenentwicklung nachgewiesen werden konnten. Rezente overwash-Prozesse sind auf die heutigen Dünen beschränkt und wurden in dieser Arbeit mit der Fragestellung untersucht, ob und inwieweit das Georadar als Methode zur Prospektion von washover-Sedimenten herangezogen werden kann.
Die unmittelbare Nachbarschaft der beiden Nehrungshaken von Sylt und Amrum lässt einen ähnlichen sedimentären Aufbau, eine analoge Genese in einem einheitlichen Prozess-System sowie ein vergleichbares Alter vermuten. Durch die Untersuchungen im Norden von Amrum sollte festgestellt werden, in wie weit das für die Hörnum Odde nachgewiesene Zusammenspiel von Küstenlängstransport, Progradation, sturmflutbedingten overwash-Prozessen und die zeitliche Unterbrechung des Längenwachstums durch Sturmfluterosion auch für Amrum zutrifft. Entgegen der Erwartungen unterscheidet sich der nördliche Nehrungshaken der Insel Amrum signifikant vom südlichen Nehrungshaken der Nachbarinsel Sylt.
Studien zur Landschaftsentwicklung an der Westküste Amrums wurden in einem Modell zusammengefasst, dass die Sedimentationsbedingungen, die im Westküstenvorfeld herrschten bevor der Kniepsand an die Insel heranwanderte, beschreibt. Auf der Landoberfläche des ertrinkenden saaleeiszeitlichen Geestkerns wurden zu Beginn der Flandrischen Transgression feinkörnige Sedimente eines Misch- und Schlickwatts abgelagert. Es ist davon auszugehen, dass der damals noch weit vor der Küste Amrums liegende Kniepsand eine Barriere bildete und so an der heute hochenergetischen Westküste für strömungsberuhigte Sedimentationsbedingungen sorgte. Ein weiteres Modell beschreibt den Andockmechanismus des Kniepsandes an die Insel Amrum. Durch die Anlagerung des ehemaligen Außensandes und den damit einhergehenden Sedimentinput wurden die Bedingungen für eine großflächige Dünenbildung geschaffen.
Landau's Fermi liquid theory has been the main tool for investigating interactions between fermions at low energies for more than 50 years. It has been successful in describing, amongst other things, the mass enhancement in ³He and the thermodynamics of a large class of metals. Whilst this in itself is remarkable given the phenomenological nature of the original theory, experiments have found several materials, such as some superconducting and heavy-fermion materials, which cannot be described within the Fermi liquid picture. Because of this, many attempts have been made to understand these ''non Fermi liquid'' phases from a theoretical perspective. This will be the broad topic of the first part of this thesis and will be investigated in Chapter 2, where we consider a two-dimensional system of electrons interacting close to a Fermi surface through a damped gapless bosonic field. Such systems are known to give rise to non Fermi liquid behaviour. In particular we will consider the Ising-nematic quantum critical point of a two-dimensional metal. At this quantum critical point the Fermi liquid theory breaks down and the fermionic self-energy acquires the non Fermi liquid like {omega}²/³ frequency dependence at lowest order and within the canonical Hertz-Millis approach to quantum criticality of interacting fermions. Previous studies have however shown that, due to the gapless nature of the electronic single-particle excitations, the exponent of 2/3 is modified by an anomalous dimension {eta_psi} which changes, not only the exponent of the frequency dependence, but also the exponent of the momentum dependence of the self-energy. These studies also show that the usual 1/N-expansion breaks down for this problem. We therefore develop an alternative approach to calculate the anomalous dimensions based on the functional renormalization group, which will be introduced in the introductory Chapter 1. Doing so we will be able to calculate both the anomalous dimension renormalizing the exponent of the frequency dependence and the exponent renormalizing the momentum dependence of the self-energy. Moreover we will see that an effective interaction between the bosonic fields, mediated by the fermions, is crucial in order to obtain these renormalizations.
In the second part of this thesis, presented in Chapter 3, we return to Fermi liquid theory itself. Indeed, despite its conceptual simplicity of expressing interacting electrons through long-lived quasi-particles which behave in a similar fashion as free particles, albeit with renormalized parameters, it remains an active area of research. In particular, in order to take into account the full effects of interactions between quasi-particles, it is crucial to consider specific microscopic models. One such effect, which is not captured by the phenomenological theory itself, is the appearance of non-analytic terms in the expansions of various thermodynamic quantities such as heat-capacity and susceptibility with respect to an external magnetic field, temperature, or momentum. Such non-analyticities may have a large impact on the phase diagram of, for example, itinerant electrons near a ferromagnetic quantum phase transition. Inspired by this we consider a system of interacting electrons in a weak external magnetic field within Fermi liquid theory. For this system we calculate various quasi-particle properties such as the quasi-particle residue, momentum-renormalization factor, and a renormalization factor which relates to the self-energy on the Fermi surface. From these renormalization factors we then extract physical quantities such as the renormalized mass and renormalized electron Lande g-factor. By calculating the renormalization factors within second order perturbation theory numerically and analytically, using a phase-space decomposition, we show that all renormalization factors acquire a non-analytic term proportional to the absolute value of the magnetic field. We moreover explicitly calculate the prefactors of these terms and find that they are all universal and determined by low-energy scattering processes which we classify. We also consider the non-analytic contributions to the same renormalization factors at finite temperatures and for finite external frequencies and discuss possible experimental ways of measuring the prefactors. Specifically we find that the tunnelling density of states and the conductivity acquire a non-analytic dependence on magnetic field (and temperature) coming from the momentum-renormalization factor. For the latter we discuss how this relates to previous works which show the existence of non-analyticities in the conductivity at first order in the interaction.
There are only 3 methods for the production of heavy and superheavy (SH) nuclei, namely, fusion reactions, a sequence of neutron capture and beta(-) decay and multinucleon transfer reactions. Low values of the fusion cross sections and very short half-lives of nuclei with Z<120 put obstacles in synthesis of new elements. At the same time, an important area of SH isotopes located between those produced in the cold and hot fusion reactions remains unstudied yet. This gap could be filled in fusion reactions of 48Ca with available lighter isotopes of Pu, Am, and Cm. New neutron-enriched isotopes of SH elements may be produced with the use of a 48Ca beam if a 250Cm target would be prepared. In this case we get a real chance to reach the island of stability owing to a possible beta(+) decay of 291114 and 287112 nuclei formed in this reaction with a cross section of about 0.8 pb. A macroscopic amount of the long-living SH nuclei located at the island of stability may be produced by using the pulsed nuclear reactors of the next generation only if the neutron fluence per pulse will be increased by about three orders of magnitude. Multinucleon transfer processes look quite promising for the production and study of neutron-rich heavy nuclei located in upper part of the nuclear map not reachable by other reaction mechanisms. Reactions with actinide beams and targets are of special interest for synthesis of new neutron-enriched transfermium nuclei and not-yet-known nuclei with closed neutron shell N=126 having the largest impact on the astrophysical r-process. The estimated cross sections for the production of these nuclei allows one to plan such experiments at currently available accelerators.
In eukaryotic cells, mitochondria host ancient essential bioenergetic and biosynthetic pathways. LYR (leucine/tyrosine/arginine) motif proteins (LYRMs) of the Complex1_LYR-like superfamily interact with protein complexes of bacterial origin. Many LYR proteins function as extra subunits (LYRM3 and LYRM6) or novel assembly factors (LYRM7, LYRM8, ACN9 and FMC1) of the oxidative phosphorylation (OXPHOS) core complexes. Structural insights into complex I accessory subunits LYRM6 and LYRM3 have been provided by analyses of EM and X-ray structures of complex I from bovine and the yeast Yarrowia lipolytica, respectively. Combined structural and biochemical studies revealed that LYRM6 resides at the matrix arm close to the ubiquinone reduction site. For LYRM3, a position at the distal proton-pumping membrane arm facing the matrix space is suggested. Both LYRMs are supposed to anchor an acyl-carrier protein (ACPM) independently to complex I. The function of this duplicated protein interaction of ACPM with respiratory complex I is still unknown. Analysis of protein-protein interaction screens, genetic analyses and predicted multi-domain LYRMs offer further clues on an interaction network and adaptor-like function of LYR proteins in mitochondria.
Background: Intestinal perforation or leakage increases morbidity and mortality of surgical and endoscopic interventions. We identified criteria for use of full-covered, extractable self-expanding metal stents (cSEMS) vs. "Over the scope"-clips (OTSC) for leak closure.
Methods: Patients who underwent endoscopic treatment for postoperative leakage, endoscopic perforation, or spontaneous rupture of the upper gastrointestinal tract between 2006 and 2013 were identified at four tertiary endoscopic centers. Technical success, outcome (e.g. duration of hospitalization, in-hospital mortality), and complications were assessed and analyzed with respect to etiology, size and location of leakage.
Results: Of 106 patients (male: 75 (71%), female: 31 (29%); age (mean ± SD): 62.5 ± 1.3 years, 72 (69%) were treated by cSEMS and 34 (31%) by OTSC. For cSEMS vs. OTSC, mean treatment duration was 41.1 vs. 25 days, p<0.001, leakage size 10 (1-50) vs. 5 (1-30) mm (median (range)), and complications were observed in 68% vs. 8.8%, p<0.001, respectively. Clinical success for primary interventional treatment was observed in 29/72 (40%) vs. 24/34 (70%, p = 0.006), and clinical success at the end of follow-up was 46/72 (64%) vs. 29/34 (85%) for patients treated by cSEMS vs. OTSC; p = 0.04.
Conclusion: OTSC is preferred in small-sized lesions and in perforation caused by endoscopic interventions, cSEMS in patients with concomitant local infection or abscess. cSEMS is associated with a higher frequency of complications. Therefore, OTSC might be preferred if technically feasible. Indication criteria for cSEMS vs. OTSC vary and might impede design of randomized studies.
Background: The sodium-taurocholate cotransporting polypeptide (NTCP) is both a key bile acid (BA) transporter mediating uptake of BA into hepatocytes and an essential receptor for hepatitis B virus (HBV) and hepatitis D virus (HDV). In this study we aimed to characterize to what extent and through what mechanism BA affect HDV cell entry.
Methods: HuH-7 cells stably expressing NTCP (HuH-7/NTCP) and primary human hepatocytes (PHH) were infected with in vitro generated HDV particles. Infectivity in the absence or presence of compounds was assessed using immunofluorescence staining for HDV antigen, standard 50% tissue culture infectious dose (TCID50) assays and quantitative PCR.
Results: Addition of primary conjugated and unconjugated BA resulted in a dose dependent reduction in the number of infected cells while secondary, tertiary and synthetic BA had a lesser effect. This effect was observed both in HuH-7/NTCP and in PHH. Other replication cycle steps such as replication and particle assembly and release were unaffected. Moreover, inhibitory BA competed with a fragment from the large HBV envelope protein for binding to NTCP-expressing cells. Conversely, the sodium/BA-cotransporter function of NTCP seemed not to be required for HDV infection since infection was similar in the presence or absence of a sodium gradient across the plasma membrane. When chenodeoxycolic acid (15 mg per kg body weight) was administered to three chronically HDV infected individuals over a period of up to 16 days there was no change in serum HDV RNA.
Conclusions: Primary BA inhibit NTCP-mediated HDV entry into hepatocytes suggesting that modulation of the BA pool may affect HDV infection of hepatocytes.
The practical aim of this work is twofold. Firstly, it is to construct a theory of language based on historical-materialist premises, i.e. a theory which stresses the sociality and historicity of language, and finds in them the fundamental characteristics which make language one of the central phenomena of human life. Such a theory is inherently counterposed to the dominant theories and philosophies of language in the last century, be they Saussurean, idealistic, structuralist, psychologistic or Chomskyan etc. It also rejects vulgar materialistic accounts of language, where language is seen merely as a “reflection” of the economic base of society, as well as the version proposed in Stalin’s short pamphlet, Marxism and Linguistics, which sees language merely as a means of communication, regardless of society or class, therefore neutralised and consequently branded irrelevant for Marxist theory. In short, the first aim would be showing what language is not and what it cannot be by showing what it is.
The second aim is related to Marxist theory in general. Following the presuppositions of this work, a Marxist account of language proves to be an immensely important field of research for Marxism. The reasons are fairly simple, if one is willing to accept them: language is a certain type of social practice, it is related to the way people act, which also means that it is interconnected with consciousness, i.e. to the way people think and to the content of their thought. Language is ideological and political; it is an element of class rule and class struggle. Thus, understanding language should be of utmost importance for any socialist revolutionary project, as ideological struggle is central not only to a revolutionary period, but, perhaps even more, to a period where revolution is not even in sight. I do not wish to derogate other Marxist fields of research, but, on the contrary, to simply insist on their equal importance. Ideological phenomena should not be a secondary or inferior object of research to strictly economic phenomena, or vice-versa. In reality, those phenomena form a dialectic unity; only if theory follows suit, can a pregnant Marxist philosophy be formed.
Teil VIII unserer Serie zum “Islamischen Staat”: "Blogforum 'Kalifat des Terrors: Interdisziplinäre Perspektiven auf den Islamischen Staat".
Die Kurden feiern in diesen Tagen den Sieg über den Islamischen Staat in Kobane. Die Hauptstadt des Distrikts Ain al-Arab im Gouvernement Aleppo in Syrien liegt nahe der syrisch-türkischen Grenze. Seit Anfang 2014 ist Ain al-Arab Zentrum eines der drei selbstverwalteten Kantone Rojavas. Diese Kantone stehen unter der Kontrolle der kurdischen “Partei der Demokratischen Union” (PYD) und ihrer Verbündeten. Die PYD ist eine Schwesterpartei der PKK, sie erkennt Abdullah Öcalan als ideologischen Führer an...
Teil VII unserer Serie zum “Islamischen Staat”: "Blogforum 'Kalifat des Terrors: Interdisziplinäre Perspektiven auf den Islamischen Staat".
Viel ist in den letzten Wochen und Monaten über den so genannten „Islamischen Staat“, ISIS oder ISIL gesprochen und geschrieben worden. Die „abstrakte Bedrohungslage“, die von der „Terrormiliz“ und ihren Anhängern ausgeht, scheint jedoch der deutschen Öffentlichkeit kaum deutlicher vor Augen geführt zu werden, als bei den Demonstrationen, die von Dresden ausgehend seit geraumer Zeit in verschiedenen Großstädten stattfinden bzw. stattgefunden haben. Die Wendung gegen das Austragen von „Glaubenskriegen auf deutschem Boden“ und noch deutlicher die Sorge vor einer bevorstehenden „Islamisierung des Abendlandes“, speist sich bei diesen zu einem gewissen Teil auch aus den Bildern und Tönen, die von und über den Islamischen Staat mittels unterschiedlicher Medienkanäle verbreitet werden. Zudem werden Befürchtungen artikuliert, die durch den Islamischen Staat ausgelösten Flüchtlingswellen bewirkten einen signifikanten Zuzug von Muslimen, der zu tiefgreifenden sozio-kulturellen Veränderungen führe...
Part VI of our series on ISIS : "Blogforum 'Kalifat des Terrors: Interdisziplinäre Perspektiven auf den Islamischen Staat".
In 2014, two insurgency organisations stood out by their expansion, success and brutality: The Islamic State (IS) and Boko Haram (BH). The former emerged from the conflicts in Syria and Iraq and became a major actor in the Middle East, its influence reaching beyond the borders of its self-proclaimed “caliphate”, while the latter spread its violence throughout north-eastern Nigeria, spilling over into Cameroon, Chad and Niger. Because of their still growing success, many wonder about a possible partnership between IS and BH. To this I answer that there is a connection, but no partnership. Currently, any evidence suggesting a partnership is circumstantial at best...
Part V of our series on ISIS : "Blogforum 'Kalifat des Terrors: Interdisziplinäre Perspektiven auf den Islamischen Staat".
Since 2003, several organizations in the Arab world swore allegiance to Osama Bin Laden and al-Qaida and became part of what was been called “al-Qaeda’s affiliate network”. The emergence of al-Qaeda groups in Saudi Arabia 2003, Iraq 2004, Algeria 2007 and Yemen 2009 convinced many supporters and enemies that there was a truly global network of jihadist groups at work, commanded and controlled by the al-Qaeda leadership in Pakistan.
However, the reality was a lot more complicated. Far from being subordinate to Osama Bin Laden and Aiman al-Zawahiri, these organizations were not willing to submit to al-Qaeda command and control. Their relationship with “al-Qaeda central” was rather an alliance between independent partners of different strength. Although the al-Qaeda leadership sometimes influenced decisions taken by the regional groupings, there are numerous examples of “affiliates” ignoring its advice even regarding strategic issues.
Part IV of our series on ISIS : "Blogforum 'Kalifat des Terrors: Interdisziplinäre Perspektiven auf den Islamischen Staat".
One element within US counter-terrorism strategies is “reducing terrorist group cohesion”, as the think tank RAND recommends in one of its reports. The Combating Terrorism Center at West Point (CTC) puts these recommendations into actions. Reports like ”Cracks in the Foundation” or ”Dysfunction and Decline” vividly depict the internal disagreement and disunity between al-Qaeda central (AQ) and its regional affiliates, most of all AQ in Iraq (AQI). Albeit these reports are drafted by pundits and certainly provide meaningful and often rare insights into the inner life of the global jihadi movement, they also serve another purpose: to deliberately amplify the very same trend they describe: disunity...
ISIS' politics of sex
(2015)
Part III of our series on ISIS : "Blogforum 'Kalifat des Terrors: Interdisziplinäre Perspektiven auf den Islamischen Staat#".
In the late summer of 2014, the international community watched helplessly as ISIS unleashed widespread serious human rights violations against civilians across Syria and Iraq. Of note, were the different forms of sexual abuse initially directed against women from the Yazidi community of Sinjar, but rapidly expanded to women from many regions and backgrounds. Far from being attributable to isolated incidents or to the behavior of a few individuals, the abuses were, and continue to be, part of the “sexual politics” implemented by ISIS in all “wilayas” (regions) under its control and endorsed by its military hierarchy. The abuses represent a clear example of the use of rape as a weapon of war, based on the “theology of sexuality” in a war zone. Fatwas and theological arguments inspired by the medieval practices of historical Muslim armies provide the justification for the policies and practices.
Some observers have conjectured that oil supply shocks in the United States and in other countries are behind the plunge in the price of oil since June 2014. Others have suggested that a major shock to oil price expectations occurred when in late November 2014 OPEC announced that it would maintain current production levels despite the steady increase in non-OPEC oil production. Both conjectures are perfectly reasonable ex ante, yet we provide quantitative evidence that neither explanation appears supported by the data. We show that more than half of the decline in the price of oil was predictable in real time as of June 2014 and therefore must have reflected the cumulative effects of earlier oil demand and supply shocks. Among the shocks that occurred after June 2014, the most influential shock resembles a negative shock to the demand for oil associated with a weakening economy in December 2014. In contrast, there is no evidence of any large positive oil supply shocks between June and December. We conclude that the difference in the evolution of the price of oil, which declined by 44% over this period, compared with other commodity prices, which on average only declined by about 5%-15%, reflects oil-market specific developments that took place prior to June 2014.
This paper is motivated by the fact that nearly half of U.S. college students drop out without earning a bachelor’s degree. Its objective is to quantify how much uncertainty college entrants face about their graduation outcomes. To do so, we develop a quantitative model of college choice. The innovation is to model in detail how students progress towards a college degree. The model is calibrated using transcript and financial data. We find that more than half of college entrants can predict whether they will graduate with at least 80% probability. As a result, stylized policies that insure students against the financial risks associated with uncertain graduation have little value for the majority of college entrants.
Little attention so-far has been paid to the influence of chronobiology on the processes of nanoparticle uptake and transport into the brain, even though this transport appears to be chronobiologically controlled to a significant degree. Nanoparticles with specific surface properties enable the transport across the blood–brain barrier of many drugs that normally cannot cross this barrier. A clear dependence of the central antinociceptive (analgesic) effects of a nanoparticle-bound model drug, i.e., the hexapeptide dalargin, on the time of day was observable after intravenous injection in mice. In addition to the strongly enhanced antinociceptive effect due to the binding to the nanoparticles, the minima and maxima of the pain reaction with the nanoparticle-bound drug were shifted by almost half a day compared to the normal circadian nociception: The maximum in the pain reaction after i.v. injection of the nanoparticle-bound dalargin occurred during the later rest phase of the animals whereas the normal pain reaction and that of a dalargin solution was highest during the active phase of the mice in the night. This important shift could be caused by an enhanced endo- and exocytotic particulates transport activity of the brain capillary endothelial cells or within the brain during the rest phase.
Microtubules execute diverse mitotic events that are spatially and temporally separated; the underlying regulation is poorly understood. By combining drug treatments, large-scale immunoprecipitation and mass spectrometry, we report the first comprehensive map of mitotic phase-specific protein interactions of the microtubule-end binding protein, EB1. EB1 interacts with some, but not all, of its partners throughout mitosis. We show that the interaction of EB1 with Astrin-SKAP complex, a key regulator of chromosome segregation, is enhanced during prometaphase, compared to anaphase. We find that EB1 and EB3, another EB family member, can interact directly with SKAP, in an SXIP-motif dependent manner. Using an SXIP defective mutant that cannot interact with EB, we uncover two distinct pools of SKAP at spindle microtubules and kinetochores. We demonstrate the importance of SKAP's SXIP-motif in controlling microtubule growth rates and anaphase onset, without grossly disrupting spindle function. Thus, we provide the first comprehensive map of temporal changes in EB1 interactors during mitosis and highlight the importance of EB protein interactions in ensuring normal mitosis.
Seit einem Jahr ist im Umfeld der Vereinten Nationen immer wieder von einem „Human Rights Up Front Aktionsplan“ zu hören. Erst kürzlich forderte Generalsekretär Ban Ki-moon die Mitgliedstaaten in einer Ansprache zu den Prioritäten der UN 2015 auf den Aktionsplan zu unterstützen. Doch was ist das für eine Initiative und welche Resultate hat sie bislang hervorgebracht? Diesen Fragen geht dieser Beitrag auf den Grund.
Im Rahmen dieser Arbeit werden verschiedene Modellsysteme untersucht, die Metriken der klassischen Allgemeinen Relativitätstheorie mit Erweiterungen vergleichen, in denen Ereignishorizonte nicht existieren müssen. Die untersuchten Korrekturterme sind durch Schwachfeldmessungen, wie sie zum Beispiel in unserem Sonnensystem durchgeführt werden, nicht überprüfbar. Es ist deshalb nötig solche Systeme zu betrachten, in denen die vollständigen Gleichungen berücksichtigt werden müssen und keine Entwicklungen für schwache Felder gemacht werden können. Es gibt eine Reihe von astrophysikalischen Systemen, die diese Bedingungen erfüllen, wie das Galaktische Zentrum oder Doppelsternsysteme.
Im zweiten Kapitel der Arbeit werden Testteilchenorbits in einem Zentralpotential beschrieben und Unterschiede zwischen der klassischen und einer modifizierten Kerr-Metrik herausgearbeitet. Drei neue Phänomene der modifizierten Metrik gegenüber der Klassischen treten hier in Erscheinung. Zum einen haben Teilchen, die sich auf prograden Bahnen um den Zentralkörper drehen, ein Maximum in ihrer Winkelgeschwindigkeit. Zum anderen ist das Phänomen des frame-draggings deutlich schwächer ausgeprägt. Schließlich tritt ein letzter stabiler Orbit für entsprechend schnell rotierende Zentralkörper nicht mehr auf. Gleichzeitig sind die Unterschiede in den beiden Metriken für große Abstände (r > 10m) nahezu vernachlässigbar. In Kapitel 3 werden diese Ergebnisse auf zwei unterschiedliche Modelle zur Beschreibung von Akkretionsscheiben angewendet. Untersucht wird zum einen das Verhalten der Eisen-Kα-Emissionslinie und zum anderen der Energiefluss aus einer Akkretionsscheibe.
In der Form der Eisen-Kα-Emissionslinie gibt es eine deutliche Zunahme des rotverschobenen Anteils der Strahlung in der modifizierten Kerr-Metrik gegenüber der klassischen Kerr-Metrik. Die Akkretionsscheibe nach Page und Thorne zeigt unter Verwendung der modifizierten Kerr-Metrik eine signifikante Erhöhung der abgestrahlten Energie, wenn der Zentralkörper so schnell rotiert, dass kein letzter stabiler Orbit mehr auftritt. Zusätzlich gibt es hier in der Scheibe einen dunklen Ring im Vergleich zu den Bildern höherer Ordnung, die in der klassischen Kerr-Metrik auftreten. Erklärbar sind diese Phänomene dadurch, dass sich Teilchen auf stabilen Bahnen in der modifizierten Kerr-Metrik näher an den Zentralkörper heran bewegen können, als es in der klassischen Kerr-Metrik der Fall ist. Die Rotverschiebung ist für beide Fälle annäherend gleich.
Kapitel 4 gibt eine kurze Einführung in die Beschreibung von Gravitationswellen im Rahmen der linearisierten Allgemeinen Relativitätstheorie. Hier wird als Modell ein Binärsystem, wie etwa der Hulse-Taylor-Pulsar, betrachtet. Die Unterschiede zwischen der klassischen Theorie und einer Beschreibung unter Hinzunahme von Zusatztermen sind hier erwartungsgemäß sehr gering, da die Linearisierung der Gleichungen dazu führt, dass Starkfeldeffekte vernachlässigt werden. Für große Abstände, was in diesem Fall auch schwache Felder impliziert, sind die Erweiterungen der Gleichungen vernachlässigbar. Hier werden zum Teil auch Effekte in der klassischen ART vernachlässigt.
In Kapitel 5 befindet sich ein kurzer Ausblick in die 3+1-Formulierung der Einsteingleichungen für die numerische Beschreibung von Gravitationsphänomenen. Diese Beschreibung ermöglicht es auch komplexe Systeme ohne viele nähernde Annahmen genau beschreiben zu können. Diese Systeme können zum einen Akkretionsscheiben um kompakte Objekte sein, aber auch die Verschmelzung von zwei massiven Objekten und die damit verbundenen Gravitationswellensignale. Dadurch lassen sich die Vorhersagen der ART oder etwaiger Erweiterungen präziser modellieren.
Die vorgestellten Ergebnisse liegen innerhalb der Einschränkungen durch aktuelle Messungen. Zukünftige Messungen wie genauere Beobachtungen des Galaktischen Zentrums durch das Event Horizon Telescope sind aber voraussichtlich dazu in der Lage zwischen den untersuchten Metriken zu unterscheiden.
Part II of our series on ISIS : Blogforum "Kalifat des Terrors: Interdisziplinäre Perspektiven auf den Islamischen Staat"
On Thursday January 15, only a week after the bloodyattacks in Paris by the Kouachi brothers and AmedyCoulibali, Belgium was on high alert. In a raid carriedout by police and security forces in the small villageof Verviers, two alleged terrorists were shot dead, a third suspect wasarrested. The action was part of a larger operation carried out throughout thecountry to prevent imminent attacks by a group of Islamists, some of whomwere directly tied to the war in Syria and Iraq. In the days that followed itbecame clear that the prevented attacks probably were aimed at a highranking police official. The terror threat level was subsequently raised tolevel three, indicating that the threat of attacks was imminent. What makesBelgium such a hub for Jihadis?..
Von den Realitäten im Cyberwar, oder: Die Bedeutung des Sony-Hacks für zukünftige Cyber-Konflikte
(2015)
Part VI of our series on cyberpeace "Cyberpeace: Dimensionen eines Gegenentwurfs".Ende November des vergangenen Jahres wurde das US-amerikanische Unternehmen Sony Pictures Entertainment (SPE) Opfer einer groß angelegten Hackerkampagne. Dabei wurden Daten von Angestellten und Kooperationspartnern, wie Namen, Adress- und Versicherungsangaben aber auch Finanzinformationen und Verschlüsselungsdaten entwendet und viele Arbeitsplatzrechner des SPE-Netzwerkes durch eine Schadsoftware infiziert. Aussagen hochrangiger Sony-Mitarbeiter zufolge wollten die Angreifer Sony mit den erbeuteten Daten ursprünglich um Geld erpressen. Medial wurde der Vorfall jedoch rasch mit der anstehende Premiere der von SPE produzierten Komödie “The Interview“, die sich satirisch mit der Situation in Nordkorea auseinandersetzt, in Verbindung gesetzt. Jedoch trat erst Mitte Dezember eine Hackergruppe names “Guardians of Peace” mit Forderungen gegen die Ausstrahlung des Films als Urheber der Hacking-Attacke auf und drohte mit der Veröffentlichung der entwendeten Sony-Daten. Kurz darauf wurde der Sony-Hack auch durch das FBI offiziell bestätigt und staatliche Einrichtung Nordkoreas als Urheber der Angriffe beschuldigt. In der Beweisführung bezog sich das FBI auf Erkenntnisse und Ähnlichkeiten zu früheren Vorkommnisse in den USA und Süd-Korea sowie den geografischen Standorten der IP-Adressen einiger, für den Angriff benutzen Computer...
Vorbemerkung des Autors: Dieser Artikel wurde bereits am 26. Januar im Sicherheitspolitik-Blog veröffentlicht. Es handelt sich um den Auftaktbeitrag eines Blogforums zum “Islamischen Staat”, das von dem Autor dieses Beitrags organisiert wurde (siehe bspw. ein Beitrag zu Belgien als Brutstätte von IS-Kämpfern: http://goo.gl/QWgEip). Das Bretterblog übernimmt ausgewählte Beiträge.
This paper studies a two-country production economy with complete and frictionless financial markets and international trade of final goods in which competition in R&D leads to endogenous new firm creation and economic growth. Current monopolists ("incumbents") and potential new firms ("entrants") compete in developing patents domestically. I find that this induces negative spillover in consumption, i.e. home country's consumption decreases in response to positive productivity shocks in the foreign country. Second, there is positive spillover in R&D expenditures, i.e. home country's R&D expenditures increase in response to positive foreign productivity shocks, which is consistent with empirical evidence on international technology diffusion. Furthermore, the stylized fact in international macroeconomics that the cross-country correlation of consumption growth is significantly lower than the one of output growth is explained by the model. Fourth, net exports are negatively correlated with output as in the data. Fifth, the model matches the high comovement of the risk-free rates and stock returns across countries. Finally, the model produces a positive value premium.