Free University of Berlin

About: Free University of Berlin is a education organization based out in Berlin, Germany. It is known for research contribution in the topics: Population & Context (language use). The organization has 35195 authors who have published 66525 publications receiving 2094403 citations. The organization is also known as: FU Berlin.

Vortex Core-Driven Magnetization Dynamics

Abstract: Time-resolved x-ray imaging shows that the magnetization dynamics of a micron-sized pattern containing a ferromagnetic vortex is determined by its handedness, or chirality. The out-of-plane magnetization in the nanometer-scale vortex core induces a three-dimensional handedness in the planar magnetic structure, leading to a precessional motion of the core parallel to a subnanosecond field pulse. The core velocity was an order of magnitude higher than expected from the static susceptibility. These results demonstrate that handedness, already well known to be important in biological systems, plays an important role in the dynamics of microscopic magnets.

Structural Vector Autoregressive Analysis

Abstract: Structural vector autoregressive (VAR) models are important tools for empirical work in macroeconomics, finance, and related fields. This book not only reviews the many alternative structural VAR approaches discussed in the literature, but also highlights their pros and cons in practice. It provides guidance to empirical researchers as to the most appropriate modeling choices, methods of estimating, and evaluating structural VAR models. The book traces the evolution of the structural VAR methodology and contrasts it with other common methodologies, including dynamic stochastic general equilibrium (DSGE) models. It is intended as a bridge between the often quite technical econometric literature on structural VAR modeling and the needs of empirical researchers. The focus is not on providing the most rigorous theoretical arguments, but on enhancing the reader's understanding of the methods in question and their assumptions. Empirical examples are provided for illustration.

Ca2+/calmodulin-dependent formation of hydrogen peroxide by brain nitric oxide synthase.

Abstract: L-Arginine-derived nitric oxide (NO) acts as an inter- and intra-cellular signal molecule in many mammalian tissues including brain, where it is formed by a flavin-containing Ca2+/calmodulin-requiring NO synthase with NADPH, tetrahydrobiopterin (H4biopterin) and molecular oxygen as cofactors. We found that purified brain NO synthase acted as a Ca2+/calmodulin-dependent NADPH:oxygen oxidoreductase, catalysing the formation of hydrogen peroxide at suboptimal concentrations of L-arginine or H4biopterin, which inhibited the hydrogen peroxide formation with half-maximal effects at 11 microM and 0.3 microM respectively. Half-maximal rates of L-citrulline formation were observed at closely similar concentrations of these compounds, indicating that the NO synthase-catalysed oxygen activation was coupled to the synthesis of L-citrulline and NO in the presence of L-arginine and H4biopterin. N omega-Nitro-L-arginine, its methyl ester and N omega-monomethyl-L-arginine inhibited the synthesis of L-citrulline from L-arginine (100 microM) with half-maximal effects at 0.74 microM, 2.8 microM and 15 microM respectively. The N omega-nitro compounds also blocked the substrate-independent generation of hydrogen peroxide, whereas N omega-monomethyl-L-arginine did not affect this reaction. According to these results, activation of brain NO synthase by Ca2+ at subphysiological levels of intracellular L-arginine or H4biopterin may result in the formation of reactive oxygen species instead of NO, and N omega-nitro-substituted L-arginine analogues represent useful tools to effectively block NO synthase-catalysed oxygen activation.

When inverted faces are recognized: the role of configural information in face recognition.

Abstract: The identification of upright faces seems to involve a special sensitivity to “configural” information, the processing of which is less effective when the face is inverted. However the precise meaning of “configural” remains unclear. Five experiments are presented, which showed that the disruption of the processing of relational, rather than holistic, information largely determines the occurrence as well as the size of the face-inversion effect. In Experiment 1, faces could be identified either by unique combinations of local information (e.g. a specific eye colour plus hair colour) or by unique relational information (e.g. nose-mouth distance). The former showed no inversion effect, whereas the latter did. A combination of local and relational information (Experiment 2) again produced an inversion effect, although this effect was smaller than that found when only relational information was used. The results were replicated in Experiment 3 when differences in the brightness of local features were used ins...

Intergenerational Transfers of Time and Money in European Families: Common Patterns - Different Regimes?

Abstract: Summary The ‘generational contract’ is the most important and also the most contentious dimension of contemporary welfare systems. Much of the debate on how to reform it is still truncated, however, by focusing on its public dimension only, especially on pensions and health-care provisions. For a full account, the transfer of resources between adult generations in the family needs to be included as well. So far, research on family transfers has almost exclusively been limited to singlecountry studies. In this article, we present a comparative study of financial transfers and social support in ten Western European countries based on the Survey of Health, Ageing and Retirement in Europe (SHARE) conducted in 2004. Our results confirm, at the European level, the existence of a common transfer pattern. There is a net downward flow from the older to the younger generations, both by inter vivos financial transfers and by social support. Transfers from the elderly parents to their children are much more frequent and also usually much more intense than those in the opposite direction. The positive balance decreases with age but even those over the age of 70 clearly remain net givers. Our results also demonstrate that country-specific transfer patterns follow the typology of welfare regimes. Transfers from parents to children are less frequent but more intense in the Southern European countries than in the Nordic ones, with the Continental European countries being somewhere in between the two. This welfare regime effect still holds after controlling for the most relevant characteristics of the parents.