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See detailItaconic acid indicates cellular but not systemic immune system activation
Meiser, Johannes; Kraemer, Lisa; Jäger, Christian UL et al

in Oncotarget (2018), 9(63),

Itaconic acid is produced by mammalian leukocytes upon pro-inflammatory activation. It appears to inhibit bacterial growth and to rewire the metabolism of the host cell by inhibiting succinate ... [more ▼]

Itaconic acid is produced by mammalian leukocytes upon pro-inflammatory activation. It appears to inhibit bacterial growth and to rewire the metabolism of the host cell by inhibiting succinate dehydrogenase. Yet, it is unknown whether itaconic acid acts only intracellularly, locally in a paracrine fashion, or whether it is even secreted from the inflammatory cells at meaningful levels in peripheral blood of patients with severe inflammation or sepsis. The aim of this study was to determine the release rate of itaconic acid from pro-inflammatory activated macrophages in vitro and to test for the abundance of itaconic acid in bodyfluids of patients suffering from acute inflammation. We demonstrate that excretion of itaconic acid happens at a low rate and that it cannot be detected in significant amounts in plasma or urine of septic patients or in liquid from bronchial lavage of patients with pulmonary inflammation. We conclude that itaconic acid may serve as a pro-inflammatory marker in immune cells but that it does not qualify as a biomarker in the tested body fluids. [less ▲]

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See detailModellierung eines PVT-basierten Wärmepumpensystems auf der Basis von CO2 Direktverdampfung
Rullof, Johannes UL; Lambers, Klaus Jürgen; Blieske, Ulf et al

in Proceedings of Deutsche Kälte- und Klimatagung DKV 2018 (2018)

Die Systemkombination aus Wärmepumpe und solarthermischen Absorber, basierend auf freier Konvektion und Strahlung, und Photovoltaik (PV) in einem Modul (PVT-Modul) kann aufgrund der Reduzierung des ... [more ▼]

Die Systemkombination aus Wärmepumpe und solarthermischen Absorber, basierend auf freier Konvektion und Strahlung, und Photovoltaik (PV) in einem Modul (PVT-Modul) kann aufgrund der Reduzierung des Heizwärmebedarfs von Gebäuden und des verstärkten Betriebs von Wärmepumpen während der Niedrigstrompreiszeiten am Tage und dem damit verbundenen höheren Strahlungsanteil der Umweltwärme zukünftig eine Alternative zu zwangskonvektions-basierten Luft-Wärmepumpen sein. Der Beitrag beschäftigt sich mit einem CO2-Wärmepumpensystem, bestehend aus einem neuartigen Solar-Hybridmodul, welches einen mikrokanal-basierten Verdampfer einer CO2-Wärmepumpe mit einem PV-Modul vereint (PVT-direkt). Um die Machbarkeit des neuartigen PVT-direkt-Wärmepumpensystems zu demonstrieren, wird im Rahmen eines Forschungsprojekts ein funktionsfähiges PVT-direkt-Modul konstruiert und schließlich als Teil eines CO2-Wärmepumpensystems getestet und modelliert. Die Besonderheit der Kombination eines thermischen Absorbers mit einer Wärmepumpe liegt in der Erschließung der Solarenergie und Umgebungsenergie als Energiequelle. Hierbei ist die Kenntnis über die thermische Leistung des PVT-Moduls unter anderem durch den konvektiven Wärmeübergang zwischen dem PVT-Modul und der Umgebung relevant. Sowohl der Modulneigungswinkel (Anströmwinkel) und die Windrichtung (Azimutwinkel) haben einen nicht zu vernachlässigenden Einfluss auf den resultierenden Wärmeübergangskoeffi-zienten der erzwungenen Konvektion. Da im Rahmen einer Literaturrecherche keine für das PVT-Modul direkt zu übertragenden experimentelle Untersuchungen und Berechnungsgrundlagen zur Bestimmung des konvektiven Wärmeübergangs gefunden werden konnten, wurde mit Hilfe der Software ANSYS Fluent eine CFD-Simulation zum konvektiven Wärmeübergang am PVT-Modul durchgeführt, deren Ergebnisse in dieser Arbeit präsentiert werden. [less ▲]

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See detailA Game Theoretic Analysis of the Twitter Follow-Unfollow Mechanism
Chen, Jundong; Hossain, Md Shafaeat; Brust, Matthias R. UL et al

in International Conference on Decision and Game Theory for Security (2018)

Twitter users often crave more followers to increase their social popularity. While a variety of factors have been shown to attract the followers, very little work has been done to analyze the mechanism ... [more ▼]

Twitter users often crave more followers to increase their social popularity. While a variety of factors have been shown to attract the followers, very little work has been done to analyze the mechanism how Twitter users follow or unfollow each other. In this paper, we apply game theory to modeling the follow-unfollow mechanism on Twitter. We first present a two-player game which is based on the Prisoner’s Dilemma, and subsequently evaluate the payoffs when the two players adopt different strategies. To allow two players to play multiple rounds of the game, we propose a multi-stage game model. We design a Twitter bot analyzer which follows or unfollows other Twitter users by adopting the strategies from the multi-stage game. We develop an algorithm which enables the Twitter bot analyzer to automatically collect and analyze the data. The results from analyzing the data collected in our experiment show that the follow-back ratios for both of the Twitter bots are very low, which are 0.76% and 0.86%. This means that most of the Twitter users do not cooperate and only want to be followed instead of following others. Our results also exhibit the effect of different strategies on the follow-back followers and on the non-following followers as well. [less ▲]

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See detailAdaptive multi-patch isogeometric analysis based on locally refined B-splines
Gu, J.; Yu, T. T.; Le, V. L. et al

in Computer Methods in Applied Mechanics and Engineering (2018), 339

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See detailDevelopment of a Control Strategy for a PVT-based CO2 Heat Pump
Rullof, Johannes UL; Lambers, Klaus Jürgen; Blieske, Ulf et al

in Proceedings of 7th International Energy and Sustainability Conference (IESC) (2018)

In recent years, the possibility of combining photovoltaics (PV) and solar thermal collectors into one solar hybrid module (PVT-module) has been increasingly investigated. PVT-modules produce thermal and ... [more ▼]

In recent years, the possibility of combining photovoltaics (PV) and solar thermal collectors into one solar hybrid module (PVT-module) has been increasingly investigated. PVT-modules produce thermal and electrical energy at the same time. Since the efficiency of a photovoltaic module decreases with increasing temperature, the temperature of the heat transfer media is often limited to about 30 °C and the PVT-module is combined with a heat pump, which increases the temperature on the “warm side”. A common approach is to integrate the PVT-module directly as an evaporator in a heat pump system (PVT-direct). This paper presents the development of a control strategy for a PVT-based CO2 heat pump that takes into account solar radiation, ambient temperature, wind speed, evaporator temperature and compressor power. The developed control strategy provides different operating modes depending on the solar radiation supply as well as the ambient temperature. [less ▲]

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See detailThe Fragmentation of Reception Conditions for Asylum Seekers in the European Union: Protecting Fundamental Rights or Preventing Long-Term Integration?
Silga, Janine UL

in Freedom, Security & Justice: European Legal Studies (2018), (3), 87-115

This article investigates the unequal treatment of asylum seekers across the European Union (EU). In particular, this article explores the way in which Directive 2013/33/EU (the “Reception Conditions ... [more ▼]

This article investigates the unequal treatment of asylum seekers across the European Union (EU). In particular, this article explores the way in which Directive 2013/33/EU (the “Reception Conditions Directive”) itself allows for the creation of different categories of asylum seekers who enjoy variable reception conditions as a result. This runs counter the stated objective of the Reception Conditions Directive to harmonise reception conditions in the EU. The fragmented treatment of asylum seekers has become more acute with the current “refugee crisis”, which has highlighted the deficiencies inherent in the reception system created by the Reception Conditions Directive. This article hypothesises that this is caused by the underlying double objective of the EU reception system, namely, to protect the fundamental rights of asylum seekers, while preventing secondary movements within the EU. Examining both the situation at the EU level and in three EU Member States, the article shows the particular challenges of the EU reception system grappling with its seemingly irreconcilable double objective. In the end, the article concludes by pointing out the risk of dismantling asylum by giving in to migration management objectives in the current context. [less ▲]

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See detailReport on France
Cuniberti, Gilles UL; Bordian, Nicolina

in Ferrari, Franco (Ed.) Iura Novit Curia in International Arbitration (2018)

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See detailModeriert die Familienumwelt die Erblichkeit kognitiver Fähigkeiten
Gottschling, Juliana UL; Hahn, Elisabeth; Spinath, Frank M.

Scientific Conference (2018)

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See detailBuchbesprechung von: Quellen zur Landesgeschichte der Rheinprovinz im 19. und 20. Jahrhundert. Teil 2: Oberpräsidium und Regierungsbezirk Koblenz.
Uhrmacher, Martin UL

in Hemecht: Zeitschrift für Luxemburger Geschichte (2018), 70(4), 109-110

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See detailModeling of Complex Microcracking in Quasi-Brittle Materials: Numerical Methods and Experimental Validations
Nguyen, Thanh Tung UL; Yvonnet, J.; Bornert, M. et al

in Advances in Multi-Physics and Multi-Scale Couplings in Geo-Environmental Mechanics (2018)

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See detailLuxemburgs Wissenschaftliche Produktivität im Vergleich zu Deutschland, Frankreich und Belgien
Dusdal, Jennifer UL; Powell, Justin J W UL

in University of Luxembourg; SCRIPT (Eds.) Nationaler Bildungsbericht Luxemburg 2018 (2018)

Dieser Beitrag vergleicht das luxemburgische Hochschul- und Wissenschaftssystem mit drei weiteren Mitgliedsstaaten der Europäischen Union – Deutschland, Frankreich und Belgien. Gemessen wird der ... [more ▼]

Dieser Beitrag vergleicht das luxemburgische Hochschul- und Wissenschaftssystem mit drei weiteren Mitgliedsstaaten der Europäischen Union – Deutschland, Frankreich und Belgien. Gemessen wird der wissenschaftliche Output anhand wissenschaftlicher peer-reviewed Zeitschriftenbeiträge aus dem von Thomson Reuters (jetzt: Clarivate Analytics) bereitgestellten Web of Science Citation Index Expanded (SCIE). Ein Vergleich der vier Universitätssektoren zeigt, dass Deutschland und Belgien mit ihren forschungsstarken und internationalen Universitäten einen wesentlich höheren Institutionalisierungsgrad aufweisen als Frankreich und Luxemburg. Ein Vergleich der außeruniversitären Sektoren belegt eine hohe Ausdifferenzierung Deutschlands und Frankreichs im Gegensatz zu Belgien und Luxemburg. In Luxemburg gibt es eine vielfältige und leistungsstarke Forschungslandschaft, die besonders internationalisiert ist. [less ▲]

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See detailStructural shape optimization by IGABEM and particle swarm optimization algorithm
Sun, S. H.; Yu, T. T.; Nguyen, Thanh Tung UL et al

in Engineering Analysis with Boundary Elements (2018), 88

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See detailA Phase field method for modeling anodic dissolution induced stress corrosion crack propagation
Nguyen, Thanh Tung UL; Bolivar, J.; Shi, Y. et al

in Corrosion Science (2018), 132

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See detailRare-earth nickelates RNiO3: thin films and heterostructures
Catalano, S.; Gibert, M.; Fowlie, J. et al

in REPORTS ON PROGRESS IN PHYSICS (2018), 81(4),

This review stands in the larger framework of functional materials by focussing on heterostructures of rare-earth nickelates, described by the La, Pr, Nd Sm,., Lu. Nickelates are characterized by a rich ... [more ▼]

This review stands in the larger framework of functional materials by focussing on heterostructures of rare-earth nickelates, described by the La, Pr, Nd Sm,., Lu. Nickelates are characterized by a rich phase diagram of structural and physical properties and serve as a benchmark for the physics of phase transitions in correlated oxides where electron-lattice coupling plays a key role. Much of the recent interest in nickelates concerns heterostructures, that is single layers of thin film multilayers or superlattices, with the general objective of modulating their physical properties through strain control, confinement or interface effects. We will discuss the extensive studies on nickelate heterostructures as well as outline different approaches to tuning and controlling their physical properties and, finally, review application concepts for future devices. [less ▲]

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See detailDVC‐based image subtraction to detect microcracking in lightweight concrete
Chateau, C.; Nguyen, Thanh Tung UL; Bornert, M. et al

in Strain (2018), 54

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See detailMultiple Cracks Interactions in Stress Corrosion Cracking: In Situ Observation by Digital Image Correlation and Phase Field Modeling
Bolivar, J.; Nguyen, Thanh Tung UL; Shi, Y. et al

in Proceedings of the 18th International Conference on Environmental Degradation of Materials in Nuclear Power Systems – Water Reactors (2018)

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See detailMulti-inclusions modeling by adaptive XIGA based on LR B-splines and multiple level sets
Gu, J.; Yu, T. T.; Le, V. L. et al

in Finite Elements in Analysis and Design (2018), 148

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See detailMigration: a theoretical comparison on countries' welfare
Zanaj, Skerdilajda UL

in International Journal of Economic Theory (2018)

We compare the effects of migration on the production of public goods, income taxes, and on the welfare of residents in the sending and in the receiving country. Migration is driven by income di¤erences ... [more ▼]

We compare the effects of migration on the production of public goods, income taxes, and on the welfare of residents in the sending and in the receiving country. Migration is driven by income di¤erences between countries. Alternative wage adjustment scenarios are considered: fully flexible wages; upward rigidity, and unemployment. We show that in all scenarios, emigration is welfare detrimental for the origin country. Migration is welfare improving for the destination country in presence of flexible wages and upward rigidity, but it has detrimental effects in presence of unemployment. [less ▲]

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See detailH2020 PROJECT CEASEVAL. Evaluation of the Common European Asylum System under Pressure and Recommendations for Further Development
Nienaber, Birte UL; Vianelli, Lorenzo UL; Paraschivescu, Claudia UL et al

Poster (2018)

Within CEASEVAL, the University of Luxembourg leads Work Package 4 (WP4) on “Borders and the Mobility of Migrants”. The aim of WP4 is to develop a framework to analyse the interactions between borders and ... [more ▼]

Within CEASEVAL, the University of Luxembourg leads Work Package 4 (WP4) on “Borders and the Mobility of Migrants”. The aim of WP4 is to develop a framework to analyse the interactions between borders and the mobility of migrants (asylum seekers, refugees and irregular migrants), thus also addressing the relation between asylum systems and Schengen regime. In order to do so, WP4 investigates the functioning of the internal and external EU borders in the governance of migrants’ mobility by looking specifically at the ways in which bordering processes are implemented when confronted with the mobility of migrants. The research draws from an extensive empirical study in 7 different countries: France, Germany, Greece, Hungary, Luxembourg, Spain and Turkey. Qualitative interviews with migrants (asylum seekers, refugees and irregular migrants) and institutional actors (border agents, policymakers, representatives of institutions, etc.), as well as ethnographic observations of border agencies and border points are conducted in these case studies. The objectives of this qualitative fieldwork are to identify mobility trajectories, understand how these are shaped by border policies, and compare bordering processes. The work package will result in 7 country reports (one for each case study), a comparative report, a policy brief, and an online interactive map. [less ▲]

Detailed reference viewed: 60 (12 UL)