References of "2008"
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See detailComment on "Huge Excitonic Effects in Layered Hexagonal Boron Nitride"
Wirtz, Ludger UL; Marini, Andrea; Gruning, Myrta et al

in Physical Review Letters (2008), 100(18),

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See detailLogarithmic Window Increase for TCP Westwood+ for Improvement in High Speed, Long Distance Networks
Kliazovich, Dzmitry UL; Granelli, Fabrizio; Miorandi, Daniele

in Computer Networks (2008), 52(12), 2395-2410

The majority of current Internet applications uses Transmission Control Protocol (TCP) for ensuring reliable end-to-end delivery of data over IP networks. The resulting path is, generally speaking ... [more ▼]

The majority of current Internet applications uses Transmission Control Protocol (TCP) for ensuring reliable end-to-end delivery of data over IP networks. The resulting path is, generally speaking, characterized by fairly large propagation delays (of the order of tens to hundreds of milliseconds) and increasing available bandwidth. Current TCP performance is far from representing an optimal solution in such operating conditions. The main reason lies in the conservative congestion control strategy employed, which does not let TCP to exploit the always increasing available path capacity. As a consequence, TCP optimization has been an active research topic in the research community over the last 25 years, boosted in the last few years by the widespread adoption of high-speed optical fiber links in the backbone and the emergence of supercomputing networked applications from one side and tremendous growth of wireless bandwidth in network access from another. This has led to the introduction of several alternative proposals for performing congestion control. Most of them focus on the effectiveness of bandwidth utilization, introducing more ‘‘aggressive” congestion control strategies. However, such approaches result often in unfairness among flows with substantially different RTTs, or do not present the inter-protocol fairness features required for incremental network deployment. In this paper, we propose TCP LogWestwood+, a TCP Westwood+ enhancement based on a logarithmic increase function, targeting adaptation to the high-speed wireless environment. The algorithm shows low sensitivity with respect to RTT value, while maintaining high network utilization in a wide range of network settings. The performance, fairness and stability properties of the proposed TCP LogWestwood+ are studied analytically, and then validated by means of an extensive set of experiments including computer simulations and wide area Internet measurements. [less ▲]

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See detailKann man Wasser waschen? Kinder experimentieren mit Wasser
Sunnen, Patrick UL; Fautsch, Linda; Hoffmann, Isabelle et al

in www.Widerstreit-Sachunterricht.de (2008), 6(11),

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See detailMagnetic domains and annealing-induced magnetic anisotropy in nanocrystalline soft magnetic materials
Suzuki, K.; Ito, N.; Saranu, S. et al

in Journal of Applied Physics (2008), 103(7), 7301-7303

The magnetic domains of nanocrystalline Fe84Nb6B10 annealed under static and rotating magnetic fields have been investigated by means of magneto-optical Kerr effect (MOKE) microscopy in order to clarify ... [more ▼]

The magnetic domains of nanocrystalline Fe84Nb6B10 annealed under static and rotating magnetic fields have been investigated by means of magneto-optical Kerr effect (MOKE) microscopy in order to clarify the origin of the dramatic magnetic softening brought about by rotating field annealing. The coercivity (Hc) values after static- and rotating-magnetic field annealings are 5.9 and 3.0  A/m, respectively. The MOKE image after static field annealing implies a highly coherent uniaxial anisotropy (Ku) in the sample whereas no sign of such a strong Ku is evident in the domain configuration after rotating field annealing. Our analytical solution of the random anisotropy model with additional Ku predicts that the fluctuating amplitude of the effective anisotropy (δK) in nanocrystalline Fe84Nb6B10 decreases from 20 to 11 J/m3 by removing Ku. The observed reduction of Hc may be attributed to this decrease in δK induced by rotating field annealing. [less ▲]

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See detailRegulation of superoxide production in neutrophils: role of calcium influx
Bréchard, Sabrina UL; Tschirhart, Eric UL

in Journal of Leukocyte Biology (2008), 84(5), 1223-1237

Upon stimulation, activation of NADPH oxidase complexes in neutrophils produces a burst of superoxide anions contributing to oxidative stress and the development of inflammatory process. Store-operated ... [more ▼]

Upon stimulation, activation of NADPH oxidase complexes in neutrophils produces a burst of superoxide anions contributing to oxidative stress and the development of inflammatory process. Store-operated calcium entry (SOCE), whereby the depletion of intracellular stores induces extracellular calcium influx, is known to be a crucial element of NADPH oxidase regulation. However, the mechanistic basis mediating SOCE is still only partially understood, as is the signal-coupling pathway leading to modulation of store-operated channels. This review emphasizes the role of calcium influx in the control of the NADPH oxidase and summarizes the current knowledge of pathways mediating this extracellular calcium entry in neutrophils. Such investigations into the cross-talk between NADPH oxidase and calcium might allow the identification of novel pharmacological targets with clinical use, particularly in inflammatory diseases. [less ▲]

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See detailMagnetic Nanorods: Genesis, Self-Organization and Applications
Birringer, R.; Wolf, H.; Lang, C. et al

in Zeitschrift für Physikalische Chemie (2008), 222(2-3), 229-255

Magnetic-field-assisted self-assembly of magnetic dipole moment carrying iron nanoparticles is shown to result in the formation of magnetic and mechanically stiff nanoscale rods. The cooperative behavior ... [more ▼]

Magnetic-field-assisted self-assembly of magnetic dipole moment carrying iron nanoparticles is shown to result in the formation of magnetic and mechanically stiff nanoscale rods. The cooperative behavior of an ensemble of such rods and bundles thereof exhibits self-organized pattern formation on different length scales. Pattern formation on large length scales reveals great similarity with physical systems undergoing spinodal decomposition. Possible applications for dipolar magnetic nanorods in the field of perpendicular storage media are highlighted. We discuss an aerosol-synthesis-route allowing to prepare ferrofluids (FF) with shape-anisotropic particles constituting the magnetic phase immersed in the nonmagnetic carrier fluid. These so-called nanorod FF unveil a two orders of magnitude increase of viscosity enforced by an applied field of 10mT even at shear rates larger than 10-2s. This raises prospects for applications in microfluidics and MEMS. [less ▲]

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See detailMagnetic-field-dependent small-angle neutron scattering on random anisotropy ferromagnets
Michels, Andreas UL; Weissmüller, J.

in Reports on Progress in Physics (2008), 71(6), 0665011-06650137

We report on the recently developed technique of magnetic-field-dependent small-angle neutron scattering (SANS), with attention to bulk ferromagnets exhibiting random magnetic anisotropy. In these ... [more ▼]

We report on the recently developed technique of magnetic-field-dependent small-angle neutron scattering (SANS), with attention to bulk ferromagnets exhibiting random magnetic anisotropy. In these materials, the various magnetic anisotropy fields (magnetocrystalline, magnetoelastic, and/or magnetostatic in origin) perturb the perfectly parallel spin alignment of the idealized ferromagnetic state. By varying the applied magnetic field, one can control one of the ordering terms which competes with the above-mentioned perturbing fields. Experiments which explore the ensuing reaction of the magnetization will therefore provide information not only on the field-dependent spin structure but, importantly, on the underlying magnetic interaction terms. This strategy, which underlies conventional studies of hysteresis loops in magnetometry, is here combined with magnetic SANS. While magnetometry generally records only a single scalar quantity, the integral magnetization, SANS provides access to a vastly richer data set, the Fourier spectrum of the response of the spin system as a function of the magnitude and orientation of the wave vector. The required data-analysis procedures have recently been established, and experiments on a number of magnetic materials, mostly nanocrystalline or nanocomposite metals, have been reported. Here, we summarize the theory of magnetic-field-dependent SANS along with the underlying description of random anisotropy magnets by micromagnetic theory. We review experiments which have explored the magnetic interaction parameters, the value of the exchange-stiffness constant as well as the Fourier components of the magnetic anisotropy field and of the magnetostatic stray field. A model-independent approach, based on the experimental autocorrelation function of the spin misalignment, provides access to the characteristic length of the spin misalignment. The field dependence of this quantity is in quantitative agreement with the predictions of micromagnetic theory. Experiments on nanocomposite ferromagnets reveal that the jump of the magnetization at internal phase boundaries leads to a significant magnetostatic perturbing field, with an unusual 'clover-leaf' SANS pattern as the experimental signature. Furthermore, SANS experiments have been used to monitor the orientation of magnetic domains as well as the length scale of intradomain spin misalignment. [less ▲]

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See detailSuperTarget and Matador: resources for exploring drug-target relationships
Guenther, Stefan; Kuhn, Michael; Dunkel, Mathias et al

in Nucleic Acids Research (2008), 36(SI), 919-922

The molecular basis of drug action is often not well understood. This is partly because the very abundant and diverse information generated in the past decades on drugs is hidden in millions of medical ... [more ▼]

The molecular basis of drug action is often not well understood. This is partly because the very abundant and diverse information generated in the past decades on drugs is hidden in millions of medical articles or textbooks. Therefore, we developed a one-stop data warehouse, SuperTarget that integrates drug-related information about medical indication areas, adverse drug effects, drug metabolization, pathways and Gene Ontology terms of the target proteins. An easy-to-use query interface enables the user to pose complex queries, for example to find drugs that target a certain pathway, interacting drugs that are metabolized by the same cytochrome P450 or drugs that target the same protein but are metabolized by different enzymes. Furthermore, we provide tools for 2D drug screening and sequence comparison of the targets. The database contains more than 2500 target proteins, which are annotated with about 7300 relations to 1500 drugs; the vast majority of entries have pointers to the respective literature source. A subset of these drugs has been annotated with additional binding information and indirect interactions and is available as a separate resource called Matador. SuperTarget and Matador are available at http://insilico.charite.de/supertarget and http://matador.embl.de. [less ▲]

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See detailDe l'Austrasie à Sarre-Lor-Lux: la «Grande Région», une entité historique?
Pauly, Michel UL

in Annales de l'Est (2008), n° spécial

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See detailVon einem Urkundenschrein, einer Kanone mit Wappen und 418 Häusern Vorwort zu den städtischen Rechnungsbüchern 1444-1453
Pauly, Michel UL; Moulin, Claudine

in Pauly, Michel; Moulin, Claudine (Eds.) Die Rechnungsbücher der Stadt Luxemburg. Drittes Heft 1444-1453 (2008)

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See detailWhat kind of citizen? What kind of democracy? Citizenship education and the Scottish Curriculum for Excellence.
Biesta, Gert UL

in Scottish Educational Review (2008), 40(2), 38-52

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See detailJacky Antoine: une âme de pédagogue
Goedert, Maly UL; Weber, Jean-Marie UL

in Transfert (2008)

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See detailWider das Lernen. Die Wiedergewinnung einer Sprache für Erziehung im Zeitalter des Lernens.
Biesta, Gert UL

in Vierteljahresschrift für wissenschaftliche Pädagogik (2008), 84(2), 179-194

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See detailJenseits der Speckgürtel: Wanderungsabsichten von Schulabsolventen und der demographische Wandel im ländlichen Raum
Chilla, Tobias UL; Morhardt, Tobias; Braun, Boris

in Raumforschung und Raumordnung (2008), 66(3), 260-270

The population of many regions in rural areas declines as mainly young adults leave. Simultaneously, only few people move into these areas if processes like suburbanisation do not play a substantial role ... [more ▼]

The population of many regions in rural areas declines as mainly young adults leave. Simultaneously, only few people move into these areas if processes like suburbanisation do not play a substantial role. In this situation, young adults must be regarded as a crucial group for the future of any region. Demographic, economic, and societal prosperity depends on them to a large extent. At the same time, school graduates are increasingly forced to be more and more mobile by changing and more volatile labour markets. The article focuses on the motivations of graduates while making their decisions to leave their home district or to stay. Based on this analysis, it asks which political instruments are appropriate in these regions beyond ‘commuter-belts’. Considering the local context, the authorities have to combine policies and instruments including family policy, regional marketing and educational aspects. The empirical findings are based on a case study in the Haßberge district in Northern Bavaria. [less ▲]

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See detailJohanns Traum von der Kaiserkrone. Die vergeblichen Bemühungen König Johanns von Böhmen um die Kaiserwürde
Pauly, Michel UL

in Zeitschrift für Historische Forschung (2008), 35

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See detailCentral limit theorems for double Poisson integrals
Peccati, Giovanni UL; Taqqu, Murad S.

in Bernoulli (2008), 14(3), 791--821

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See detailRemembering the schoolmaster's blood-red pen. The story of the exercise books and the story of the children of the time (1950-1970)
Herman, Frederik UL; Surmont, Melanie; Depaepe, Marc et al

in History of Education (2008), 3(2), 351-375

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See detailBurkholder's submartingales from a stochastic calculus perspective
Peccati, Giovanni UL; Yor, Marc

in Illinois Journal of Mathematics (2008), 52(3), 815--824

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See detailMetastable behavior of donors in CuGaSe2 under illumination
Siebentritt, Susanne UL; Rissom, Thorsten

in Applied Physics Letters (2008), 92

Several metastable effects have been observed in chalcopyrite solar cells. Recently, they have been related to the amphoteric behavior of the Se vacancy. We give an independent experimental evidence on ... [more ▼]

Several metastable effects have been observed in chalcopyrite solar cells. Recently, they have been related to the amphoteric behavior of the Se vacancy. We give an independent experimental evidence on this amphoteric behavior. By comparing charge carrier densities obtained from Hall effect measurements under illumination and in the dark, we conclude that illumination removes compensating donors. [less ▲]

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