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See detailLa diplomatie au service du commerce. Les relations politiques entre les Pays-Bas espagnols et les villes hanséatiques de Hambourg, de Brême et de Lubeck pendant les années 1560
Weis, Monique UL

in Poussou, J.-P.; Baury, R.; Vignal-Souleyreau, M.-C. (Eds.) Monarchie, noblesse et diplomaties européennes. Mélanges en l’honneur de Jean-François Labourdette (2005)

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See detailDiplomats at the Bar: The European External Action Service before EU Courts
Gatti, Mauro UL

in European Law Review (2014)

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See detailDipolar correlations in a nanocomposite: A neutron scattering study of Nanoperm Fe89Zr7B3Cu
Michels, Andreas UL; Vecchini, C.; Moze, O. et al

in Physical Review. B, Condensed Matter and Materials Physics (2006), 74(13), 1344071-13440713

We present results for the magnetic-field, temperature, and neutron-polarization dependence of the small-angle neutron scattering intensity in the soft magnetic iron-based nanocomposite Nanoperm ... [more ▼]

We present results for the magnetic-field, temperature, and neutron-polarization dependence of the small-angle neutron scattering intensity in the soft magnetic iron-based nanocomposite Nanoperm (Fe89Zr7B3Cu). An unusual “clover-leaf-shaped” intensity distribution on the detector is attributed to the dipolar stray fields around the nanosized iron particles, which are embedded in an amorphous magnetic matrix of lesser saturation magnetization. The dipole field induces spin disorder, correlating the spin misalignment of neighboring particles and matrix over several particle spacings. The clover-leaf-shaped anisotropy is observed over a wide range of applied magnetic field and momentum transfer. It persists up to several hundred degrees Kelvin above the Curie temperature of the matrix phase, indicating that some degree of magnetic coupling persists even when the matrix is paramagnetic. [less ▲]

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See detailDipolar spin-misalignment correlations in inhomogeneous magnets: Comparison between neutron scattering and micromagnetic
Erokhin, Sergey; Berkov, Dmitry; Michels, Andreas UL

in Physical Review. B, Condensed Matter (2015), 92(1), 014427

In inhomogeneous bulk ferromagnets, the dominating sources of spin disorder are related to spatial variations of (i) the magnitude of the local saturation magnetization and of (ii) the magnitude and/or ... [more ▼]

In inhomogeneous bulk ferromagnets, the dominating sources of spin disorder are related to spatial variations of (i) the magnitude of the local saturation magnetization and of (ii) the magnitude and/or direction of the magnetic anisotropy field. For the particular example of a porous ferromagnet, where the magnetization inhomogeneity is at maximum, we demonstrate, by means of experimental neutron scattering data and micromagnetic simulations, the anisotropic character of magnetization fluctuations induced by the dipolar interaction. [less ▲]

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See detailDipolar-coupled moment correlations in clusters of magnetic nanoparticles
Bender, Philipp Florian UL; Wetterskog, E.; Honecker, Dirk UL et al

in Physical Review. B, Condensed Matter (2018), 98

Here, we resolve the nature of the moment coupling between 10-nm dimercaptosuccinic acid–coated magnetic <br />nanoparticles. The individual iron oxide cores were composed of >95% maghemite and ... [more ▼]

Here, we resolve the nature of the moment coupling between 10-nm dimercaptosuccinic acid–coated magnetic <br />nanoparticles. The individual iron oxide cores were composed of >95% maghemite and agglomerated to <br />clusters. At room temperature the ensemble behaved as a superparamagnet according to Mössbauer and magnetization <br />measurements, however, with clear signs of dipolar interactions. Analysis of temperature-dependent <br />ac susceptibility data in the superparamagnetic regime indicates a tendency for dipolar-coupled anticorrelations <br />of the core moments within the clusters. To resolve the directional correlations between the particle moments <br />we performed polarized small-angle neutron scattering and determined the magnetic spin-flip cross section <br />of the powder in low magnetic field at 300 K. We extract the underlying magnetic correlation function of <br />the magnetization vector field by an indirect Fourier transform of the cross section. The correlation function <br />suggests nonstochastic preferential alignment between neighboring moments despite thermal fluctuations, with <br />anticorrelations clearly dominating for next-nearest moments. These tendencies are confirmed by Monte Carlo <br />simulations of such core clusters. [less ▲]

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See detailDipole-field-induced spin disorder in a nanocomposite soft magnet
Michels, Andreas UL; Vecchini, C.; Moze, O. et al

in Europhysics Letters (2005), 72(2), 249-255

We report on a study of a magnetic nanocomposite of the Nanoperm type (Fe89Zr7B3Cu1) by magnetic small-angle neutron scattering (SANS). The understanding of the magnetic microstructure of these materials ... [more ▼]

We report on a study of a magnetic nanocomposite of the Nanoperm type (Fe89Zr7B3Cu1) by magnetic small-angle neutron scattering (SANS). The understanding of the magnetic microstructure of these materials leaves much to be desired since we lack techniques capable of resolving the spin structure in the bulk with nanoscale resolution. Here, we present an analysis of the SANS signal by which one cannot only characterise the nanoscale structure of the spin system, but which allows to identify origin and structure of the perturbing field. In Nanoperm, an unusual angular anisotropy of the scattering suggests that the local spin misalignment decorates, as the most important perturbing field, dipole stray fields around the crystalline phase of the composite. [less ▲]

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See detailDirac Cones, Topological Edge States, and Nontrivial Flat Bands in Two-Dimensional Semiconductors with a Honeycomb Nanogeometry
Kalesaki, Efterpi UL; Delerue, Christophe; Morais Smith, Cristiane et al

in Physical Review X (2014), 4(1), 011010

We study theoretically two-dimensional single-crystalline sheets of semiconductors that form a honeycomb lattice with a period below 10 nm. These systems could combine the usual semiconductor properties ... [more ▼]

We study theoretically two-dimensional single-crystalline sheets of semiconductors that form a honeycomb lattice with a period below 10 nm. These systems could combine the usual semiconductor properties with Dirac bands. Using atomistic tight-binding calculations, we show that both the atomic lattice and the overall geometry influence the band structure, revealing materials with unusual electronic properties. In rocksalt Pb chalcogenides, the expected Dirac-type features are clouded by a complex band structure. However, in the case of zinc-blende Cd-chalcogenide semiconductors, the honeycomb nanogeometry leads to rich band structures, including, in the conduction band, Dirac cones at two distinct energies and nontrivial flat bands and, in the valence band, topological edge states. These edge states are present in several electronic gaps opened in the valence band by the spin-orbit coupling and the quantum confinement in the honeycomb geometry. The lowest Dirac conduction band has S-orbital character and is equivalent to the π−π⋆ band of graphene but with renormalized couplings. The conduction bands higher in energy have no counterpart in graphene; they combine a Dirac cone and flat bands because of their P-orbital character. We show that the width of the Dirac bands varies between tens and hundreds of meV. These systems emerge as remarkable platforms for studying complex electronic phases starting from conventional semiconductors. Recent advancements in colloidal chemistry indicate that these materials can be synthesized from semiconductor nanocrystals. [less ▲]

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See detailThe dirac oscillator of arbitrary spin
del Sol Mesa, Antonio UL

in Journal of Physics: A Mathematical and General (1996)

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See detailDirac sigma models from gauging
Salnikov, Vladimir UL; Strobl, Thomas

in Journal of High Energy Physics (2013)

The G/G WZW model results from the WZW-model by a standard procedure of gauging. G/G WZW models are members of Dirac sigma models, which also contain twisted Poisson sigma models as other examples. We ... [more ▼]

The G/G WZW model results from the WZW-model by a standard procedure of gauging. G/G WZW models are members of Dirac sigma models, which also contain twisted Poisson sigma models as other examples. We show how the general class of Dirac sigma models can be obtained from a gauging procedure adapted to Lie algebroids in the form of an equivariantly closed extension. The rigid gauge groups are generically infinite dimensional and a standard gauging procedure would give a likewise infinite number of 1-form gauge fields; the proposed construction yields the requested finite number of them. Although physics terminology is used, the presentation is kept accessible also for a mathematical audience. [less ▲]

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See detailDire et faire percevoir la violence. Réflexions sur les écritures de Calixthe Beyala et Ananda Devi
Barthelmebs-Raguin, Hélène UL

in Barthelmebs-Raguin, Hélène; Freyheit, Matthieu (Eds.) Criminelles. Pourquoi les femmes tuent (2018)

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See detailDire la folie – Expériences de patients psychiatriques (1930-1980)
Majerus, Benoît UL

in Guillemain, Herve; Guignard, Laurence; Tison, Stéphane (Eds.) Les malades dans l'instution psychiatrique au XXe siècle (2013)

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See detailDire/Montrer. Au coeur du sens
de Chanay, Hugues; Colas-Blaise, Marion UL; Le Guern, Odile

Book published by Université de Savoie - Première édition (2013)

L'ouvrage examine les concepts de dire et de montrer, empruntés par les sciences humaines à la philosophie de Wittgenstein (Tractatus Logico-philosophus), et fondamentaux pour la sémiotique, la ... [more ▼]

L'ouvrage examine les concepts de dire et de montrer, empruntés par les sciences humaines à la philosophie de Wittgenstein (Tractatus Logico-philosophus), et fondamentaux pour la sémiotique, la linguistique énonciative, la sémantique, l’analyse de discours, et les sciences de l’interprétation en général. Les contributeurs/trices de l’ouvrage, à partir de ces références fondatrices, font dialoguer ces divers champs disciplinaires des sciences du langage et ils étudient l’application de ces deux concepts minutieusement définis à différents objets de sens. Tel est le point de départ des huit contributions de fond réunies ici. [less ▲]

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See detailDirect and indirect excitons in boron nitride polymorphs: A story of atomic configuration and electronic correlation
Sponza, Lorenzo; Amara, Hakim; Attaccalite, Claudio et al

in Physical Review. B, Condensed Matter (2018), 98(12), 125206

We present a detailed discussion of the electronic band structure and excitonic dispersion of hexagonal boron nitride (hBN) in the single layer configuration and in three bulk polymorphs (usual AA′ ... [more ▼]

We present a detailed discussion of the electronic band structure and excitonic dispersion of hexagonal boron nitride (hBN) in the single layer configuration and in three bulk polymorphs (usual AA′ stacking, Bernal AB, and rhombohedral ABC). We focus on the changes in the electronic band structure and the exciton dispersion induced by the atomic configuration and the electron-hole interaction. Calculations are carried out at the level of ab initio many-body perturbation theory (GW and Bethe Salpeter equation) and of a purposely developed tight-binding model. We confirm the change from direct to indirect electronic gap when going from single layer to bulk systems and we give a detailed account of its origin by comparing the effect of different stacking sequences. We emphasize that the inclusion of the electron-hole interaction is crucial for the correct description of the momentum-dependent dispersion of the excitations. As a result the electron-hole dispersion is flatter than the one obtained from the band structure. In the AB stacking this effect is particularly important as the lowest-lying exciton is predicted to be direct despite the indirect electronic band gap. [less ▲]

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See detailDirect and Indirect Measures of Learning in Visual Search
Reuter, Robert UL

Doctoral thesis (2013)

In this thesis, we will explore direct and indirect measures of learning in a visual search task commonly called contextual cueing. In the first part, we present a review of the scientific literature on ... [more ▼]

In this thesis, we will explore direct and indirect measures of learning in a visual search task commonly called contextual cueing. In the first part, we present a review of the scientific literature on contextual cueing, in order to give the readers of this thesis a better general idea of existing evidence and open questions within this relatively new research field. The aims of our own experimental studies presented in the succeeding chapters are the following ones: (1) to replicate and extend the findings described in the various papers by Marvin Chun and various colleagues on contextual cueing of visual attention; (2) to explore the nature of memory representations underlying the observed learning effects, especially whether learning is actually implicit and whether memory representations are distinctive, episodic and instance-based or rather distributed, continuous and graded; (3) to extend the study of contextual cueing to more realistic visual stimuli, in order to test its robustness across various situations and validate its adaptive value in ecologically sound conditions; and (4) to investigate whether such knowledge about the association between visual contexts and “meaningful” locations can be (automatically) transferred to other tasks, namely a change detection task. In a first series of four experiments, we tried to replicate the documented contextual cueing effect using a wide range of various direct measures of learning (tasks that are supposed to be related to explicit knowledge) and we systematically varied the distinctiveness of context configurations to study its effect on both direct and indirect measures of learning. We also ran a series of neural network simulations (briefly described in the general discussion of this thesis), based on a very simple association-learning mechanism, that not only account for the observed contextual cueing effect, but also yield rather specific predictions about future experimental data: contextual cueing effects should also be observed when repetitions of context configurations are not perfect, i.e., the networks were able to react to slightly distorted versions of repeating contexts in a similar way than they did to completely identical contexts. Human participants, we conjectured, should therefore (if the simple connectionist model captures some relevant aspects of the contextual cueing effect) become faster at detecting targets surrounded by context configurations that are only partially identical from trial to trial compared to those trials where the context configurations were randomly generated. These predictions were tested in a second series of experiments using pseudo-repeated context configurations, where some distractor items were either displaced from trial to trial or their orientation changed, while conserving their global layout. In a third series of experiments, we used more realistic images of natural landscapes as background contexts to establish the robustness of the contextual cueing effect as well as its ecological relevance claimed by Chun and colleagues. We furthermore added a second task to these experiments to study whether the acquired knowledge about the background-target location associations would (automatically) transfer to another visual search task, namely a change detection task. If participants have learned that certain locations of the repeated images are “important”, since they contain the target item to look for, then changes occurring at those specific locations should lead to less “change blindness” than changes occurring at other irrelevant locations. We used two different types of instructions to introduce this second task after the visual search task, where we either stressed the link between the two tasks, i.e., telling them that remembering the “important” locations for each image could be used to find the changes faster, or we simply told them to perform the second task without any reference to the first one. We will close this thesis with a general discussion, combining findings based on our review of the existing research literature and findings based on our own experimental explorations of the contextual cueing effect. By this we will discuss the implications of our empirical studies for the scientific investigation of contextual cueing and implicit learning, in terms of theoretical, empirical and methodological issues. [less ▲]

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See detailDirect and Indirect Measures of Sexual Maturity Preferences Differentiate Subtypes of Child Sexual Abusers
Schmidt, Alexander F. UL; Gykiere, Kim; Vanhoeck, Kris et al

in SEXUAL ABUSE-A JOURNAL OF RESEARCH AND TREATMENT (2014), 26(2), 107-128

To aid risk assessment, management, and treatment planning it is essential to assess child sexual abusers' deviant sexual interests (DSI) and preferences (DSP) for sex with children. However, measurement ... [more ▼]

To aid risk assessment, management, and treatment planning it is essential to assess child sexual abusers' deviant sexual interests (DSI) and preferences (DSP) for sex with children. However, measurement of DSI/DSP is fraught with psychometric problems. In consequence, research interest has shifted to latency-based indirect measures as a measurement approach to complement self-report and physiological assessment. Utilizing the Explicit and Implicit Sexual Interest Profile (EISIP)a multimethod approach consisting of self-report, viewing time, and Implicit Association Test (IAT) DSI/DSP measureswe replicated phallometric DSI/DSP differences between child sexual abuser subgroups in a sample of intrafamilial, extrafamilial, and child pornography offenders. DSI/DSP was associated with recidivism risk, offense-behavioral measures of pedophilic interest, and sexual fantasizing. It also negatively correlated with antisociality. Distinguishing between child sexual abuser subtypes and being related to recidivism risk, the EISIP is a useful tool for sexual offender assessments. [less ▲]

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See detailDirect clustering of a two-mode binary data-matrix
Krolak-Schwerdt, Sabine UL; Orlik, Peter

in Universität des Saarlandes: Arbeiten der Fachrichtung Psychologie (1998), 186

In this paper a discrete, categorical model is proposed for two-:­ mode data matrices with binary entries Xij E {0, 1}. The method operates directly upon a raw input (objects by attributes) data array by ... [more ▼]

In this paper a discrete, categorical model is proposed for two-:­ mode data matrices with binary entries Xij E {0, 1}. The method operates directly upon a raw input (objects by attributes) data array by determining two-mode submatrices whose entries entirely have values x;j = 1. In addition, different submatrices are required to have a minimum set of objectattribute- pairs in common. Objects and attributes are classified simultaneously in a number ofjoint clusters. The method may be characterized as a non-hierarchical clustering procedure and in its model function to predict the data it is similar to Boolean factor analy􀢛is. Basically, the proposed method dubbed ' GRIDPAT' (for 'PATtern analysis of GRIDs') was developped for the structural representation of self concept data. Its relations to basic notions of Formal Concept Analysis and blockmodeling are discussed. An illustrative application of the approach is provided. [less ▲]

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