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See detailA Critical Review of the Literature on School Dropout
De Witte, Kristof; Cabus, Sofie; Thyssen, Geert UL et al

in Educational Research Review. The Journal of the European Association for Research on Learning and Instruction (EARLI) (2013), 10

Detailed reference viewed: 334 (7 UL)
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See detailCritical role of cPLA2 in Aβ oligomer-induced neurodegeneration and memory deficit.
Desbène, Cédric; Malaplate-Armand, Catherine; Youssef, Ihsen et al

in Neurobiology of Aging (2012), 33(6), 1123-17-1123-29

Soluble beta-amyloid (Aβ) oligomers are considered to putatively play a critical role in the early synapse loss and cognitive impairment observed in Alzheimer's disease. We previously demonstrated that Aβ ... [more ▼]

Soluble beta-amyloid (Aβ) oligomers are considered to putatively play a critical role in the early synapse loss and cognitive impairment observed in Alzheimer's disease. We previously demonstrated that Aβ oligomers activate cytosolic phospholipase A2 (cPLA2), which specifically releases arachidonic acid from membrane phospholipids. We here observed that cPLA2 gene inactivation prevented the alterations of cognitive abilities and the reduction of hippocampal synaptic markers levels noticed upon a single intracerebroventricular injection of Aβ oligomers in wild type mice. We further demonstrated that the Aβ oligomer-induced sphingomyelinase activation was suppressed and that phosphorylation of Akt/protein kinase B (PKB) was preserved in neuronal cells isolated from cPLA2−/− mice. Interestingly, expression of the Aβ precursor protein (APP) was reduced in hippocampus homogenates and neuronal cells from cPLA2−/− mice, but the relationship with the resistance of these mice to the Aβ oligomer toxicity requires further investigation. These results therefore show that cPLA2 plays a key role in the Aβ oligomer-associated neurodegeneration, and as such represents a potential therapeutic target for the treatment of Alzheimer's disease. Keywords Alzheimer's disease; Cytosolic phospholipase A2; Soluble beta-amyloid oligomers; Memory; Apoptosis; Synaptotoxicity; Amyloid precursor protein [less ▲]

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See detailCritical Role of the Exchange Interaction for the Electronic Structure and Charge-Density-Wave Formation in TiSe2
Hellgren, Maria; Baima, Jacopo; Bianco, Raffaello et al

in Physical Review Letters (2017), 119

We show that the inclusion of screened exchange via hybrid functionals provides a unified description of the electronic and vibrational properties of TiSe2. In contrast to local approximations in density ... [more ▼]

We show that the inclusion of screened exchange via hybrid functionals provides a unified description of the electronic and vibrational properties of TiSe2. In contrast to local approximations in density functional theory, the explicit inclusion of exact, nonlocal exchange captures the effects of the electron-electron interaction needed to both separate the Ti-d states from the Se-p states and stabilize the charge-density- wave (CDW) (or low-T) phase through the formation of a p-d hybridized state. We further show that this leads to an enhanced electron-phonon coupling that can drive the transition even if a small gap opens in the high-T phase. Finally, we demonstrate that the hybrid functionals can generate a CDW phase where the electronic bands, the geometry, and the phonon frequencies are in agreement with experiments. [less ▲]

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See detailA Critical Security Analysis of the Password-Based Authentication Honeywords System Under Code-Corruption Attack
Genç, Ziya Alper UL; Lenzini, Gabriele UL; Ryan, Peter UL et al

in Information Systems Security and Privacy (2019, July)

Password-based authentication is a widespread method to access into systems, thus password files are a valuable resource often target of attacks. To detect when a password file has been stolen, Juels and ... [more ▼]

Password-based authentication is a widespread method to access into systems, thus password files are a valuable resource often target of attacks. To detect when a password file has been stolen, Juels and Rivest introduced the Honeywords System in 2013. The core idea is to store the password with a list of decoy words that are ``indistinguishable'' from the password, called honeywords. An adversary that obtains the password file and, by dictionary attack, retrieves the honeywords can only guess the password when attempting to log in: but any incorrect guess will set off an alarm, warning that file has been compromised. In a recent conference paper, we studied the security of the Honeywords System in a scenario where the intruder also manages to corrupt the server's code (with certain limiting assumptions); we proposed an authentication protocol and proved it secure despite the corruption. In this extended journal version, we detail the analysis and we extend it, under the same attacker model, to the other two protocols of the original Honeywords System, the setup and change of password. We formally verify the security of both of them; further, we discuss that our design suggests a completely new approach that diverges from the original idea of the Honeywords System but indicates an alternative way to authenticate users which is robust to server's code-corruption. [less ▲]

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See detailCritical size limits for collinear and spin spiral magnetism in CoCr$_2$O$_4$
Zákutná, Dominika; Alemayehu, Adam; Vlček, Jan et al

in Physical Review. B, Condensed Matter and Materials Physics (2019)

The multiferroic behavior of CoCr$_2$O$_4$ results from the appearance of conical spin-spiral magnetic ordering, which induces electric polarization. The magnetic ground state has a complex size dependent ... [more ▼]

The multiferroic behavior of CoCr$_2$O$_4$ results from the appearance of conical spin-spiral magnetic ordering, which induces electric polarization. The magnetic ground state has a complex size dependent behavior, which collapses when reaching a critical particle size. Here, the magnetic phase stability of CoCr$_2$O$_4$ in the size range of 3.6 - 14.0 nm is presented in detail using the combination of neutron diffraction with XYZ polarization analysis and macroscopic magnetization measurements. We establish critical coherent domain sizes for the formation of the spin spiral and ferrimagnetic structure and reveal the evolution of the incommensurate spin spiral vector with particle size. We further confirm the presence of ferroelectric polarization in the spin spiral phase for nanocrystalline CoCr$_2$O$_4$. <P /> [less ▲]

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See detailCritical size limits for collinear and spin-spiral magnetism in $CoCr_2\mathrmO_4$
Zákutná, D.; Alemayehu, A.; Vlček et al

in Physical Review. B, Condensed Matter and Materials Physics (2019), 100

The multiferroic behavior of CoCr2O4 results from the appearance of conical spin-spiral magnetic ordering, which induces electric polarization. The magnetic ground state has a complex size-dependent ... [more ▼]

The multiferroic behavior of CoCr2O4 results from the appearance of conical spin-spiral magnetic ordering, which induces electric polarization. The magnetic ground state has a complex size-dependent behavior, which collapses when reaching a critical particle size. Here the magnetic phase stability of CoCr2O4 in the size range of 3.6–14.0 nm is presented in detail using the combination of neutron diffraction with XYZ polarization analysis and macroscopic magnetization measurements. We establish critical coherent domain sizes for the formation of the spin spiral and ferrimagnetic structure and reveal the evolution of the incommensurate spin spiral vector with particle size. We further confirm the presence of ferroelectric polarization in the spin spiral phase for nanocrystalline CoCr2O4. [less ▲]

Detailed reference viewed: 31 (1 UL)
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See detailCritical thinking and the question of critique. Some lessons from deconstruction.
Biesta, Gert UL; Stams, G. J. J. M.

in Studies in Philosophy & Education (2001), 20(1), 57-74

Detailed reference viewed: 58 (0 UL)
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See detailCritical transitions in chronic disease: transferring concepts from ecology to systems medicine
Trefois, Christophe UL; Antony, Paul UL; Goncalves, Jorge UL et al

in Current Opinion in Biotechnology (2015), 34

Ecosystems and biological systems are known to be inherently complex and to exhibit nonlinear dynamics. Diseases such as microbiome dysregulation or depression can be seen as complex systems as well and ... [more ▼]

Ecosystems and biological systems are known to be inherently complex and to exhibit nonlinear dynamics. Diseases such as microbiome dysregulation or depression can be seen as complex systems as well and were shown to exhibit patterns of nonlinearity in their response to perturbations. These nonlinearities can be revealed by a sudden shift in system states, for instance from health to disease. The identification and characterization of early warning signals which could predict upcoming critical transitions is of primordial interest as prevention of disease onset is a major aim in health care. In this review, we focus on recent evidence for critical transitions in diseases and discuss the potential of such studies for therapeutic applications. [less ▲]

Detailed reference viewed: 363 (52 UL)
See detailCritical voices in science education research: Narratives of academic journeys
Bazzul, Jesse; Siry, Christina UL

Book published by Sense / Brill (2019)

Detailed reference viewed: 86 (14 UL)
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See detailLa critique de la légitimité démocratique de l'Union européenne selon la Cour constitutionnelle fédérale de Karlsruhe
Gerkrath, Jörg UL

in Duprat, G. (Ed.) L'Union européenne, droit, politique, démocratie, Collection Politique d'aujourd'hui (1996)

Detailed reference viewed: 108 (1 UL)
See detailCritique systémique de la démocratie
Sosoe, Lukas UL

Presentation (2015, May)

Detailed reference viewed: 76 (3 UL)
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See detailCroatia’s Leap towards Political Equality: Rules and Players
Glaurdic, Josip UL

in Matland, Richard; Montgomery, Kathleen (Eds.) Women’s Access to Political Power in Post-Communist Europe (2003)

Detailed reference viewed: 76 (0 UL)
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See detailLa Croisée des discours dans le Quatuor algérien d’Assia Djebar
Barthelmebs-Raguin, Hélène UL

in Discours et la Langue (Le) (2015)

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See detailCross Layer Implementation of a Multi-User MIMO Test Bed
Jalden, Niklas; Bergman, Svante; Zetterberg, Per et al

in Wireless Communications and Networking Conference (WCNC), 2010 IEEE (2010)

This paper describes an implementation of a realtime multi-user multiple-input multiple-output (MU-MIMO) communication system, with cross-layer channel-aware scheduling. The system is implemented using ... [more ▼]

This paper describes an implementation of a realtime multi-user multiple-input multiple-output (MU-MIMO) communication system, with cross-layer channel-aware scheduling. The system is implemented using software reconfigurable nodes that may be configured as either user terminals, or as base stations, communicating in the GSM 1800 uplink band. Three different commonly used scheduling algorithms (based on channel state information fed back by the receiver nodes) are studied and compared experimentally for three different signal to noise ratios in an indoor non line of sight environment. It is shown that channel-aware scheduling increases not only the system throughput, but also the fairness. Further, using the possibility of changing antenna polarization through software controlled switches, the multiuser gains may be increased even further, both in total throughput as well as fairness. [less ▲]

Detailed reference viewed: 133 (0 UL)
See detailCross-border access to electronic evidence: Policy and legislative challenges
Ligeti, Katalin UL; Robinson, Gavin UL

in Carrera, Sergio; Mitsilegas, Valsamis (Eds.) Constitutionalising the Security Union: Effectiveness, rule of law and rights in countering terrorism and crime (2017)

Detailed reference viewed: 155 (37 UL)
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See detailCross-border activity-travel patterns: the Luxembourg residents perspective
Sprumont, François UL; Piroth, Isabelle UL; Viti, Francesco UL

Scientific Conference (2016, October 07)

Despite its small size (2586 km2), the Grand-duchy of Luxembourg is a strong economic locomotive. Indeed, among the 380 000 available jobs in the country, 44% are occupied by cross-border workers from ... [more ▼]

Despite its small size (2586 km2), the Grand-duchy of Luxembourg is a strong economic locomotive. Indeed, among the 380 000 available jobs in the country, 44% are occupied by cross-border workers from France, Belgium and Germany. While the commuting behavior and the activity chains of the cross-border workers have been largely studied (Carpentier, 2012, Drevon et al., 2013, Gerber, 2012) this is not the case for the population living in Luxembourg. This scientific contribution aims at analyzing the daily activity chains of resident population. Do residents perform all their activities in Luxembourg? If not, in which country do they go and for which type of activity? Due to the small size of the country and plausible attraction for surrounding countries (linked to familial reasons, nationality, past residential place of residence, differentials in prices etc.) the people living in Luxembourg might conduct some activities in Belgium, France or Germany. Between June and July 2015, a multi-day survey has been implemented on 52 staff members of the University of Luxembourg working, at that time, at Walferdange campus. These individuals provided information regarding their daily activities (activity duration and location, activity type) and their travel behavior (travelling time and mode) for two weeks. Among the respondents, 35 participants are living in Luxembourg and provided information for 490 days and 1850 activities in total. The studied population is interesting in many aspects. First of all, the individuals were working in Walferdange, a city located 8 km north of Luxembourg-city, so a central geographic position. Second, this is a high-qualified and international population. Actually, the education level of the respondents is high (45% have a PhD degree, 37% a master degree) and many of them moved to Luxembourg because of the attractive labour market. Third, the income of the surveyed population is higher than the average national salary. With its limited area, one would think that individuals living in Luxembourg would cross the borders quite often for shopping, leisure activities...However, Luxembourg has abundant and various services (shopping malls, leisure and cultural places ...). Indeed close to 30% of the respondents had all their activities in Luxembourg and out of the 1850 total activities, only 130 had been done in a neighboring country. But on the other hand, one fourth of the respondents had done 75% of total activities outside Luxembourg. In a way to better understand the mobility behavior of resident population, a detailed activity chain analysis will be presented. This will be completed by a spatial analysis of the activities, in order to examine the effects of the borders on non-work related activities. Finally, different activity behaviors will be identified through a multivariate analysis. The results of this explorative analysis will be compared to the abundant literature regarding the behavior of the cross-borders workers. [less ▲]

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See detailCross-border cooperation as practice formation. Perspectives for an alternative research approach
Wille, Christian UL; Connor, Ulla UL

in Beck, Joachim (Ed.) Transdisciplinary discourses on cross-border cooperation in Europe (2019)

The paper presents a practice-sociological approach to the description and analysis of cross-border cooperation. For this purpose, the development of cooperation research, its characteristic orientations ... [more ▼]

The paper presents a practice-sociological approach to the description and analysis of cross-border cooperation. For this purpose, the development of cooperation research, its characteristic orientations as well as the fundamentals of practical theoretical thinking will be outlined. Based on this, the heuristic figure of thought of cross-border practice formation is developed, which breaks with the premises of conventional cooperation research. It will be further differentiated on the basis of four challenges of cross-border cooperation, in order to arrive at an alternative perspective on cross-border cooperation. The following is an outlook, which deals with the research-specific features of the approach presented, with a view to a future practice-sociological and multidisciplinary cooperation research. [less ▲]

Detailed reference viewed: 325 (29 UL)