Ageing and pensions in the Euro Area Survey and projection results

Population ageing will impose a significant burden on European fiscal balances, in particular through pay-as-you-go pension systems. This study presents an independent estimate of this burden for the euro area, and quantifies the impact of two reform scenarios. Based on widely used, but optimistic assumptions, the present value of future pension deficits through 2050 is estimated at 51percent of GDP, adding to the current average explicit debt stock of around 67 percent of GDP. In this calculation, the deficits currently incurred by many pension systems as revenues fall short of expenditures, are not included. Viable parametric reforms represent no durable solution to alleviate the burden sufficiently, as they can balance pension systems at best temporarily. A comprehensive reform, including reforms of current systems, and a move towards partial funding, is found to ensure permanent financial viability of the public pension system.Pensions&Retirement Systems,Environmental Economics&Policies,Economic Theory&Research,Banks&Banking Reform,Economic Stabilization

The structure of a single sharp quantum Hall edge probed by momentum-resolved tunneling

Momentum resolved magneto-tunnelling spectroscopy is performed at a single sharp quantum Hall edge. We directly probe the structure of individual integer quantum Hall (QH) edge modes, and find that an epitaxially overgrown cleaved edge realizes the sharp edge limit, where the Chklovskii picture relevant for soft etched or gated edges is no longer valid. The Fermi wavevector in the probe quantum well probes the real-space position of the QH edge modes, and reveals inter-channel distances smaller than both the magnetic length and the Bohr radius. We quantitatively describe the lineshape of principal conductance peaks and deduce an edge filling factor from their position consistent with the bulk value. We observe features in the dispersion which are attributed to fluctuations in the ground energy of the quantum Hall system.Comment: 4 pages, 3 figure

World War I Posters and the Female Form

Like Britain and continental Europe, the United States would utilize the war poster to garner both funding and public support during World War I. While war has historically been considered a masculine endeavor, a relatively large number of these posters depict the female form. Although the use of women in American World War I propaganda may not initially seem problematic, upon further inspection it becomes clear that her presence often served to promote racial and national pretentiousness. Based on the works of popular pre-war illustrators like Howard Chandler Christy and Charles Dana Gibson, the American woman was the most attractive woman in the world. Her outstanding wit, beauty and intelligence amde her the only suitable mate for the supposed racially superior American man. With the onset of war, however, the once entertaining romantic scenarios in popular monthlies and weeklies now represented what America stood to lose, and the American Girl would make the transition from magazine illustration to war poster with minimal alterations. As the war raged on, many Americans began to express fear about the possibility of German invasion, and the American woman became threatened by a perceived racially inferior force. While countless posters would explicitly address this concern, others would more subtly claim the American female as the rightful property of the American ma

World War I Posters and the Female Form

Like Britain and continental Europe, the United States would utilize the war poster to garner both funding and public support during World War I. While war has historically been considered a masculine endeavor, a relatively large number of these posters depict the female form. Although the use of women in American World War I propaganda may not initially seem problematic, upon further inspection it becomes clear that her presence often served to promote racial and national pretentiousness. Based on the works of popular pre-war illustrators like Howard Chandler Christy and Charles Dana Gibson, the American woman was the most attractive woman in the world. Her outstanding wit, beauty and intelligence amde her the only suitable mate for the supposed racially superior American man. With the onset of war, however, the once entertaining romantic scenarios in popular monthlies and weeklies now represented what America stood to lose, and the American Girl would make the transition from magazine illustration to war poster with minimal alterations. As the war raged on, many Americans began to express fear about the possibility of German invasion, and the American woman became threatened by a perceived racially inferior force. While countless posters would explicitly address this concern, others would more subtly claim the American female as the rightful property of the American ma

ModeRNA: a tool for comparative modeling of RNA 3D structure

RNA is a large group of functionally important biomacromolecules. In striking analogy to proteins, the function of RNA depends on its structure and dynamics, which in turn is encoded in the linear sequence. However, while there are numerous methods for computational prediction of protein three-dimensional (3D) structure from sequence, with comparative modeling being the most reliable approach, there are very few such methods for RNA. Here, we present ModeRNA, a software tool for comparative modeling of RNA 3D structures. As an input, ModeRNA requires a 3D structure of a template RNA molecule, and a sequence alignment between the target to be modeled and the template. It must be emphasized that a good alignment is required for successful modeling, and for large and complex RNA molecules the development of a good alignment usually requires manual adjustments of the input data based on previous expertise of the respective RNA family. ModeRNA can model post-transcriptional modifications, a functionally important feature analogous to post-translational modifications in proteins. ModeRNA can also model DNA structures or use them as templates. It is equipped with many functions for merging fragments of different nucleic acid structures into a single model and analyzing their geometry. Windows and UNIX implementations of ModeRNA with comprehensive documentation and a tutorial are freely available

Strength Assessment of a Precession Driven Dynamo

A pressure vessel, which shall be filled with eight tons of liquid sodium, has to be designed for a large-scale experimental setup to investigate flow-induced magnetic fields. In addition to the centrifugal forces and gyroscopic loads induced by the rotation about two non-parallel axes, the complex internal pressure distribution, the imbalance of the container, as well as the thermal loads resulting from the elevated temperatures, which are required for the experiments, must be taken into account. This leads to several millions of load cases. That is why a calculation procedure is developed using the finite element method, which strongly reduces the computational complexity by utilizing sector symmetry, load case decomposition and superposition. Here, the focus is to determine the most critical load cases, which will be used for the strength assessment, regarding both the static and the fatigue strength.Besides the structural strength, the welded joints and the bolted joints are analyzed. Therefore, nonlinear effects are considered, for example the contact status of the bolted joints. The submodelling technique is used to investigate structural details

RNA and protein 3D structure modeling: similarities and differences

In analogy to proteins, the function of RNA depends on its structure and dynamics, which are encoded in the linear sequence. While there are numerous methods for computational prediction of protein 3D structure from sequence, there have been very few such methods for RNA. This review discusses template-based and template-free approaches for macromolecular structure prediction, with special emphasis on comparison between the already tried-and-tested methods for protein structure modeling and the very recently developed “protein-like” modeling methods for RNA. We highlight analogies between many successful methods for modeling of these two types of biological macromolecules and argue that RNA 3D structure can be modeled using “protein-like” methodology. We also highlight the areas where the differences between RNA and proteins require the development of RNA-specific solutions

Comprehensive study of ULF upstream waves observed in the topside ionosphere by CHAMP and on the ground

Based on magnetic field measurements from the satellite CHAMP, a detailed picture could be obtained of the upstream wave (UW) distribution in the topside ionosphere. The low, near-polar orbit of CHAMP, covering all local times, allows the global distribution of this type of pulsation to be revealed. The observations from space are compared to recordings of the ground-based MM100 meridional array covering the latitude range 66° to 42° in magnetic coordinates. UWs show up very clearly in the compressional component of the satellite magnetic field data, whereas on the ground, their signature is found in the H component, but it is mixed with oscillations from field line resonant pulsations. Here we first introduce a procedure for an automated detection of UW signatures, both in ground and space data. Then a statistical analysis is presented of UW pulsations recorded during a 132-day period, centred on the autumn 2001 equinox. Observations in the top-side ionosphere reveal a clear latitudinal distribution of the amplitudes. Largest signals are observed at the equator. Minima show up at about 40° latitude. The coherence between ground and satellite wave signatures is high over wide latitude and longitude ranges. We make suggestions about the entry mechanism of UWs from the foreshock region into the magnetosphere. The clear UW signature in satellite recordings between −60° and 60° latitude allows for detailed investigations of the dependence on solar wind conditions. We test the control of solar wind speed, interplanetary magnetic field strength and cone angle on UWs. For the first time, it is possible to derive details of the Doppler-shift effect by modifying the UW frequency from direct observations. The results reconcile foreshock wave generation predictions with near-Earth observations

CHAMP observation of intense kilometer-scale field-aligned currents, evidence for an ionospheric Alfvén resonator

International audienceBursts of very intense kilometer-scale field-aligned currents (KSFACs) are observed quite frequently by the CHAMP satellite when passing through the auroral region. In extreme cases estimated current densities exceed 3 mA/m². Typical scale sizes of these KSFACs are 1 km. The low-Earth, polar orbiting satellite CHAMP allows one to assess KSFACs down to scales of a couple of 100 m based on its high-precision magnetic field vector data sampled at 50 Hz. Using data from 5 years (2001?2005) details of these currents can be investigated. In our statistical study we find that most of the KSFAC bursts and the strongest events are encountered in the cusp/cleft region. Significantly fewer events are found on the nightside. The affected region is typically 15°?20° wide in latitude. There seems to be some dependence of the current intensity on the level of magnetic activity, Kp. On the other hand, no dependence has been found on sunspot number, the solar flux level, F10.7 or the solar zenith angle. The latitude, at which KSFAC bursts are encountered, expands equatorward with increasing Kp. This trend follows well the auroral oval expansion during enhanced magnetic activity. These KSFACs are generally accompanying large-scale FAC sheets, and they are predominantly associated with Region 1 currents. We propose an explanation of the KSFACs in terms of Alfvén waves trapped in a ionospheric resonator, which is initiated when the convection electric field or current strength surpasses a critical value. Many properties of such a resonator are in agreement with our KSFAC results