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See detailGuru: Universal Reputation Module for Distributed Consensus Protocols
Biryukov, Alex UL; Feher, Daniel UL; Khovratovich, Dmitry UL

Report (2017)

In this paper we describe how to couple reputation systems with distributed consensus protocols to provide high-throughput highly-scalable consensus for large peer-to-peer networks of untrusted validators ... [more ▼]

In this paper we describe how to couple reputation systems with distributed consensus protocols to provide high-throughput highly-scalable consensus for large peer-to-peer networks of untrusted validators. We introduce reputation module Guru, which can be laid on top of various consensus protocols such as PBFT or HoneyBadger. It ranks nodes based on the outcomes of consensus rounds run by a small committee, and adaptively selects the committee based on the current reputation. The protocol can also take external reputation ranking as input. Guru can tolerate larger threshold of malicious nodes (up to slightly above 1/2) compared to the 1/3 limit of BFT consensus algorithms. [less ▲]

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See detailFlow characteristics of metallic powder grains for additive manufacturing
Peters, Bernhard UL; Pozzetti, Gabriele UL

in EPJ Web of Conferences (2017), 13001

Directed energy deposition technologies for additive manufacturing such as laser selective melting (SLM) or electron beam melting (EBM) is a fast growing technique mainly due to its flexibility in product ... [more ▼]

Directed energy deposition technologies for additive manufacturing such as laser selective melting (SLM) or electron beam melting (EBM) is a fast growing technique mainly due to its flexibility in product de- sign. However, the process is a complex interaction of multi-physics on multiple length scales that are still not entirely understood. A particular challenging task are the flow characteristics of metallic powder ejected as jets from a nozzle and shielded by an inert turbulent gas flow. Therefore, the objective is to describe numerically the complex interaction between turbulent flow and powder grains. In order to include both several physical processes and length scales an Euler-Lagrange technology is applied. Within this framework powder is treated by the Discrete-Element-Method, while gas flow is described by Euler approaches as found in classical Compu- tational Fluid Dynamics (CFD). The described method succeeded in delivering more accuracy and consistency than a standard approach based on the volume averaging technique and therefore, is suited for the solution of problems within an engineering framework. [less ▲]

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See detailPositioning Vancouver through urban sustainability strategies? The Greenest City 2020 Action Plan
Affolderbach, Julia, ; Schulz, Christian UL

in Journal of Cleaner Production (2017), 164

Cities around the world have launched greening initiatives to reduce their carbon footprint and to become more sustainable. At the same time, they have also sought to use these initiatives to position ... [more ▼]

Cities around the world have launched greening initiatives to reduce their carbon footprint and to become more sustainable. At the same time, they have also sought to use these initiatives to position themselves as climate change leaders and green champions. This paper focuses on the City of Vancouver's Greenest City 2020 Action Plan as urban policy strategy to reduce carbon emissions. Based on interviews with actors and experts involved in the development and implementation of the plan, the paper evaluates the role green leadership aspirations play in shaping urban climate change policy and how policy makers and stakeholders use policy to position the city and its greening initiatives locally and globally. In particular, it analyzes the role of competitive positioning and green leadership in sustainability initiatives and change within and beyond urban boundaries. While leadership suggests increased buy-in of residents and those involved in the implementation of the strategy and multiplication effects through learning within the region and between (peer) cities, it can also pose challenges as the interest in meeting leadership claims can impede more radical change through specific targets and implementation strategies and challenge other sustainability objectives. [less ▲]

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See detailParkinson's disease: Evaluation of a neuroprotective target and identification of candidate biomarker signatures using murine models
Ashrafi, Amer UL

Doctoral thesis (2017)

Parkinson's disease (PD) is one of the most common age-related neurologic diseases. While existing therapeutic approaches, focusing on dopamine replacement, can alleviate some of the cardinal symptoms ... [more ▼]

Parkinson's disease (PD) is one of the most common age-related neurologic diseases. While existing therapeutic approaches, focusing on dopamine replacement, can alleviate some of the cardinal symptoms, they are associated with severe adverse effects in the long-term. Therefore, identification of new therapeutic interventions to reverse, stop or slow down the progression of Parkinson’s disease is a major focus of PD research. Similarly, identifying reliable biomarkers that would enable early therapeutic intervention is another key area of current research. Here, we evaluated a recently proposed non-dopaminergic protein drug target for PD, Regulator of G-Protein Signaling 4 (RGS4), and performed preliminary studies aimed at the identification of novel biomarker signatures using two murine models of Parkinson’s disease. Recent research on new non-dopaminergic PD drug targets has indicated that inhibition of RGS4, a member of the RGS family of proteins that inactivate G-proteins, could be an effective adjuvant treatment option. However, the effectiveness of RGS4 inhibition for an array of PDlinked functional and structural neuroprotection endpoints had not yet been demonstrated. Here, we used the 6-Hydroxydopamine (6-OHDA) lesioning mouse model to address this question. We observed, using a battery of behavioral and pathological measures, that mice deficient for RGS4 are not protected from 6-OHDA induced injury, and showed enhanced susceptibility in some measures of motor function. Our results suggest that inhibition of RGS4 as a non-dopaminergic target for PD should be approached with caution. In the second part of this study, two alpha-synuclein based PD mouse models, human E46K mutated overexpressed alpha-synuclein and alpha-synuclein fibril spreading models, were used to investigate early pathological events in PD and identify novel candidate biomarker signatures for subsequent validation. Two different time points, before disease onset, and at peak disease manifestation, were analyzed in the two models. Using multiple histopathology and molecular biology techniques, we were able to identify complex changes in patterns of gene expression at early stages of the disease, well before neurodegeneration is detectable. These findings might open venues for new therapeutic strategies and provide insights on the molecular perturbations occurring during the earliest stages of the disease, paving the way for the development of a biomarker signatures for early diagnosis of Parkinson’s disease. [less ▲]

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See detailOn the arithmetic of modular forms
Wiese, Gabor UL

Presentation (2017, June 28)

In this overview talk, we will illustrate the arithmetic significance of the coefficients of modular forms, from classical examples to the modern point of view of Galois representations. From that on, one ... [more ▼]

In this overview talk, we will illustrate the arithmetic significance of the coefficients of modular forms, from classical examples to the modern point of view of Galois representations. From that on, one is naturally lead to questions on the distribution of the coefficients in various senses. We will briefly touch on some of them, report on recent theorems and state some open questions. When investigating arithmetical properties of coefficients through Galois representations, their ramification properties are an important object to study. One notices that forms of -so called- weight one play a special role that will be explained. The importance of Galois representations coming from modular forms is that one expects all Galois representations satisfying reasonable "geometric" assumption to arise in such a way. As a special case, we will explain the theorem of Khare and Wintenberger, formerly called Serre's modularity conjecture, and conjectural generalisations. Whereas Galois representations are usually very hard to calculate directly on a computer, modular forms are pretty simple to compute. We will briefly touch on this and what kind of information one can get. If time allows, we will also touch on an application to the so-called inverse Galois problem. [less ▲]

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See detailОпределение проницаемости органоминеральных грунтов с помощью диссипационных тестов, выполняемых пьезоконом
Van Baars, Stefan UL; Van De Graaf, Henk

in Russian Magazine Geoinfo (2017)

В настоящее время испытания пьезоконом (CPTu, статическое зондирование с измерением порового давления) часто используются для предварительной оценки структурных и деформационных параметров грунтов. При ... [more ▼]

В настоящее время испытания пьезоконом (CPTu, статическое зондирование с измерением порового давления) часто используются для предварительной оценки структурных и деформационных параметров грунтов. При использовании результатов тестирования пьезоконом стандартные исследования площадки, состоящие из испытаний статическим зондированием (CPT), бурения и лабораторных испытаний, могут быть оптимизированы. Коэффициент консолидации и гидравлическая проводимость (коэффициент фильтрации Кф) – параметры, необходимые для прогнозных оценок осадок во времени, могут быть получены с использованием диссипационных тестов, выполненных пьезоконом (т.е. тесты по рассеиванию порового давления, выполняемые после остановки зондирования). Тест на диссипацию основан на том, что скорость рассеивания избыточного порового давления (воды), возникающего во время вдавливания пьезокона через насыщенные водой глины и илы, зависит от коэффициента фильтрации грунтовой среды. Однако, интерпретация кривых диссипации часто проблематична, поскольку существующие методы анализа предполагают непрерывное снижение порового давления со временем, тогда как фактические кривые диссипации часто демонстрируют нестандартное поведение, интерпретация которого более сложна. В настоящей статье представлен метод интерпретации, который можно использовать для оценки коэффициента фильтрации независимо от формы кривой диссипации. Примеры результатов, полученных с использованием новой методики анализа, сравниваются с результатами, полученными с использованием лабораторных одометрических исследований. Перевод статьи на русский язык выполнен Петром Космиади. [less ▲]

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See detailDepression Burden in Luxembourg: Individual Risk Factors, Geographic Variations and the Role of Migration, 2013-2015 European Health Examination Survey
Ruiz-Castell, Maria; Kandala, Ngianga-Bakwin; Perquin, Magali et al

in Journal of Affective Disorders (2017), 222

Background: Depression is a complex mental disorder that affects an increasing proportion of the worldwide population. This study aims to estimate the prevalence of depressive symptoms in Luxembourg ... [more ▼]

Background: Depression is a complex mental disorder that affects an increasing proportion of the worldwide population. This study aims to estimate the prevalence of depressive symptoms in Luxembourg, associated risk factors and geographic variations. Additionally, it aims to assess whether first and second generation immigrants are at higher risk for depressive symptoms compared to non-immigrants. Methods: Representative cross-sectional data from 1499 residents of Luxembourg, aged 25 to 64 years, were collected from the Luxembourg European Health Survey (EHES-LUX). Depressive symptoms were defined as a score of ≥5 on the Patient Health Questionnaire for depression (PHQ-9) (i.e. mild, moderate or severe). Standard and Bayesian regression models were used to examine associations between depressive symptoms, immigration status and geographic distribution across Luxembourg. Results: The prevalence of depressive symptoms was 21.55% (15.54% mild, 3.54% moderate, and 2.49% moderately severe to severe). The odds of having depressive symptoms was higher among second generation immigrants compared to non-immigrants (OR: 1.58, 95% CI: 1.04, 2.41), independent of socioeconomic and behavioral characteristics. Healthier diet, higher social support and good health perception were protective towards experiencing depressive symptoms. One of the highest likelihoods of reporting depressive symptoms was observed in the South-West of the country with a positive effect at 80% credible region [CR] (1.42 [0.92, 2.73]). Limitations: The participation rate was low (26.7%). The cross-sectional nature of the study does not allow us to establish causality. Conclusions: Depression constitutes an important public health challenge in Luxembourg due to the impact on the overall health of the population. Social programs of health promotion should be developed to improve mental wellbeing in immigrants, especially those of second generation. [less ▲]

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See detailThe effect of training morphosyntactic markers in German and in French on multilingual fifth-graders' spelling.
Bilici, Natalia UL; Ugen, Sonja UL; Weth, Constanze UL

Scientific Conference (2017, June 26)

Many studies focussing on spelling in French and German languages show that, even by the end of the primary school, pupils have difficulties to encode morphosyntactic information in their writing ... [more ▼]

Many studies focussing on spelling in French and German languages show that, even by the end of the primary school, pupils have difficulties to encode morphosyntactic information in their writing. Particularly problematic are, for instance, capitalisation of nouns in German (Betzel 2014) or plural markers in French (Fayol et al. 2006), because they are inaudible and require knowledge that goes beyond simple phoneme-grapheme correspondences. Our paper presents how multilingual learners deal with silent morphosyntactic markers in French and German and shows the effects of an intervention training on children's spelling performance. In total our study included 228 multilingual fifth graders (mean age 11 years) with four years instruction in German and two years instruction in French. They were assigned to an intervention (n=137) and to a control group (n=91) based on the results of a spelling test in French and German. This was done by creating performance groups that were, in a second step, attributed to one of the experimental groups taking their performance into account (quasi-randomised procedure). The French test consisted of three word categories of different difficulty (nouns, verbs, adjectives). For adjectives only, position (pre- vs. post-nominal) was also manipulated. The German test focussed on three lexical-semantic characteristics (concrete nouns, abstract nouns, nominalizations) and four syntactical positions (determinant+noun, determinant+adjective+noun, adjective+noun, noun) frequent words and pseudo-words. Additionally, word frequency was manipulated within each language (frequent words vs. pseudowords). These difficulty levels have been based on the literature published on monolingual learners (French: Totereau et al. (2014), German: Funke (2005); Guenther (2007); Betzel (2014)). The children participated in 12 intervention sessions of 20 minutes each (six in German and six in French, the order was counterbalanced). Children of the intervention group were trained to improve their morphosyntactic awareness and thus spelling performance of French plurals and German capitalization. The control group received the same amount of language input than the intervention group, but they were trained on another aspect of language i.e. listening comprehension. Results from the pre-test show that multilingual children acquiring German and French show similar difficulty patterns as German or French monolinguals. The post-test shows that the intervention group improved significantly in both their German and French spelling in comparison to the control group in all word and pseudo-word categories and positions. The intervention group's performance increased especially on pseudo-words, indicating that the training had an effect on children's spelling according to syntactic regularities. The study results are specifically important to better understand the learning processes of morphosyntactic spelling in primary school. The implications on the teaching methods will be discussed. [less ▲]

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See detailThe CSD and its influence on labour law in Europe
Ratti, Luca UL

Scientific Conference (2017, June 26)

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See detailHow Mobile Phone Handovers reflect Urban Mobility: A Simulation Study
Derrmann, Thierry UL; Frank, Raphaël UL; Engel, Thomas UL et al

in Derrmann, Thierry; Frank, Raphaël; Engel, Thomas (Eds.) et al How Mobile Phone Handovers reflect Urban Mobility: A Simulation Study (2017, June 26)

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See detailUne grève sous la menace des baïonnettes allemandes
Scuto, Denis UL

Article for general public (2017)

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See detailL'Histoire d'un pays dans le potrait d'un Homme
Danescu, Elena UL

Article for general public (2017)

Il y a des personnalités qui demeurent dans la mémoire collective par l’empreinte qu’elles ont laissée sur le destin de leurs pays. Pierre Werner (29 décembre 1913 – 24 juin 2002) est de ceux-là. Ministre ... [more ▼]

Il y a des personnalités qui demeurent dans la mémoire collective par l’empreinte qu’elles ont laissée sur le destin de leurs pays. Pierre Werner (29 décembre 1913 – 24 juin 2002) est de ceux-là. Ministre d’État, Premier Ministre et ministre des Finances pendant de longues décennies, cet intellectuel catholique et démocrate résolu fut l’un des rares hommes d’État qui a traversé le XXe siècle. Animé par son humanisme chrétien profondément ancré dans la tradition et par son esprit visionnaire, il a su, avec courage et ténacité, faire évoluer la société luxembourgeoise vers plus de liberté, de solidarité et de partage, tout en ouvrant de nouveaux horizons vers un bel avenir à inventer et à bâtir dans l’unité. La diversification économique, la promotion du Luxembourg au rang de place financière internationale, le développement du secteur audiovisuel à travers le projet des satellites, l’avènement d’une Union économique et monétaire en Europe, la culture de la concertation sociale et du consensus font partie des initiatives audacieuses qu’il a transmises à ses continuateurs. Car, avec rigueur et persévérance, Pierre Werner a toujours donné corps à ses visions, en étant source d’inspiration pour les nouvelles générations. [less ▲]

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See detailASIMUT project: Aid to SItuation Management based on MUltimodal, MUltiUAVs, MUltilevel acquisition Techniques
Bouvry, Pascal UL; Chaumette, Serge; Danoy, Grégoire UL et al

in DroNet'17 Proceedings of the 3rd Workshop on Micro Aerial Vehicle Networks, Systems, and Applications (2017, June 23)

This document summarizes the activities and results of the ASIMUT project (Aid to SItuation Management based on MUltimodal, MUltiUAVs, MUltilevel acquisition Techniques) carried out by the consortium ... [more ▼]

This document summarizes the activities and results of the ASIMUT project (Aid to SItuation Management based on MUltimodal, MUltiUAVs, MUltilevel acquisition Techniques) carried out by the consortium composed of Thales, Fraunhofer IOSB, Fly-n-Sense, University of Bordeaux and University of Luxembourg. Funded by the European Defence Agency (EDA), the objectives of the ASIMUT project are to design, implement and validate algorithms that will allow the efficient usage of autonomous swarms of Unmanned Aerial Vehicles (UAVs) for surveillance missions. [less ▲]

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See detailZur Zufriedenheit von Mitgliedern des Verwaltungsrats und der Geschäftsleitung Schweizer Aktiengesellschaften mit dem "umfassenden Bericht" der Revisionsstelle : Ergebnisse einer explorativen Studie
Muessig, Anke UL

in Funk, Wilfried (Ed.) Internationale Rechnungslegung und Internationales Controlling : Herausforderungen - Handlungsfelder - Erfolgspotenziale (2017)

In der Schweiz sind zum 1. Januar 2008 die geänderten Artikel des Obligationenrechts (OR) zur Abschlussprüfung (sog. ordentliche Revision) in Kraft getreten. Ein Ziel der Reform ist es gewesen, die ... [more ▼]

In der Schweiz sind zum 1. Januar 2008 die geänderten Artikel des Obligationenrechts (OR) zur Abschlussprüfung (sog. ordentliche Revision) in Kraft getreten. Ein Ziel der Reform ist es gewesen, die Qualität der ordentlichen Revision zu erhöhen. Ansatzpunkte waren insbesondere die Verbesserung der Kommunikation der Revisionsstelle mit dem Verwaltungsrat (VR) durch die Einführung des sog. umfassenden Berichts und die Erweiterung des Prüfungsumfangs um die Prüfung der Existenz des Internen Kontrollsystems (IKS). Der vorliegende Beitrag adressiert die Unsicherheiten der Revisionsstellen beim umfassenden Bericht. Ziel ist es, erstmalig und in einer breitangelegten Befragung von VR- und GL-Mitgliedern ihre Zufriedenheit mit dem umfassenden Bericht zu erheben. Die Ergebnisse der explorativen Studie sollen den Wirtschaftsprüfungsgesellschaften Verbesserungspotenziale hinsichtlich ihrer Berichterstattung aufzeigen und Ansatzpunkte für eine „passgenaue” Berichterstattung liefern. [less ▲]

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See detailDevelopment and analysis of individual-based gut microbiome metabolic models
Magnusdottir, Stefania UL

Doctoral thesis (2017)

The human gut microbiota plays a large role in the metabolism of our diet. These microorganisms can break down indigestible materials such as polysaccharides and convert them into metabolites that the ... [more ▼]

The human gut microbiota plays a large role in the metabolism of our diet. These microorganisms can break down indigestible materials such as polysaccharides and convert them into metabolites that the human body can take up and utilize (e.g., vitamins, essential amino acids, and short-chain fatty acids). Disbalances in the gut microbiome have been associated with several diseases, including diabetes and obesity. However, little is known about the detailed metabolic crosstalk that occurs between individual organisms within the microbiome and between the microbiome and the human intestinal cells. Because of the complexity of the intestinal ecosystem, these interactions are difficult to determine using existing experimental methods. Constraint-based reconstruction and analysis (COBRA) can help identify the possible metabolic mechanisms at play in the human gut. By combining mathematical, computational, and experimental methods, we can generate hypotheses and design targeted experiments to elucidate the metabolic mechanisms in the gut microbiome. In this thesis, I first applied comparative genomics to analyze the biosynthesis pathways of eight B-vitamins in hundreds of human gut microbial species. The results suggested that many gut microbes do not synthesize any B-vitamins, that is, they depend on the host’s diet and neighboring bacteria for these essential nutrients. Second, I developed a semi-automatic reconstruction refinement pipeline that quickly generates biologically relevant genome-scale metabolic reconstructions (GENREs) of human gut microbes based on automatically generated metabolic reconstructions, comparative genomics data, and data extracted from biochemical experiments on the relevant organisms. The pipeline generated metabolically diverse reconstructions that maintain high accuracy with known biochemical data. Finally, the refined GENREs were combined with metagenomic data from individual stool samples to build personalized human gut microbiome metabolic reconstructions. The resulting large-scale microbiome models were both taxonomically and functionally diverse. The work presented in this thesis has enabled the generation of biologically relevant human gut microbiome metabolic reconstructions. Metabolic models resulting from such reconstructions can be applied to study metabolism within the human gut microbiome and between the gut microbiome and the human host. Additionally, they can be used to study the effects of different dietary components on the metabolic exchanges in the gut microbiome and the metabolic differences between healthy and diseased microbiomes. [less ▲]

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See detailWho Trade at Better Prices?
Wolff, Christian UL; Ekkayokkaya, Manapol

E-print/Working paper (2017)

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See detailMagnetic neutron scattering on Nd-Fe-B magnets
Michels, Andreas UL

Scientific Conference (2017, June 20)

Detailed reference viewed: 7 (1 UL)