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Yolanda von Vianden und das Yolanda-Epos Sieburg, Heinz E-print/Working paper (in press) Detailed reference viewed: 101 (7 UL)The edge-based strain smoothing method for compressible and nearly incompressible non-linear elasticity for solid mechanics ; ; et al E-print/Working paper (in press) Detailed reference viewed: 477 (38 UL)The mod 2 cohomology rings of congruence subgroups in the Bianchi groups ; ; Rahm, Alexander E-print/Working paper (in press) We provide new tools for the calculation of the torsion in the cohomology of congruence subgroups in the Bianchi groups : An algorithm for finding particularly useful fundamental domains, and an analysis ... [more ▼] We provide new tools for the calculation of the torsion in the cohomology of congruence subgroups in the Bianchi groups : An algorithm for finding particularly useful fundamental domains, and an analysis of the equivariant spectral sequence combined with torsion subcomplex reduction. [less ▲] Detailed reference viewed: 77 (2 UL)Parliamentary Administrations in EU Politics: The Sources and Impact of Diversity Högenauer, Anna-Lena E-print/Working paper (2019) National parliaments tend to delegate a range of tasks related to EU affairs scrutiny to their administrations. However, there is considerable variation in the extent to which national parliaments invest ... [more ▼] National parliaments tend to delegate a range of tasks related to EU affairs scrutiny to their administrations. However, there is considerable variation in the extent to which national parliaments invest in EU affairs staff. This raises two questions: what is the source of this diversity, and what is its impact on the EU affairs scrutiny of national parliaments? This paper argues that greater investments in EU affairs staff are associated with public Euroscepticism, large parliaments and parliaments with strong scrutiny powers. A large EU staff is, in turn, associated with parliaments that are relatively active in EU affairs scrutiny. This is particularly true for the 15 EU member states that joined before 2004. [less ▲] Detailed reference viewed: 4 (0 UL)The 2019 European Parliament Elections in Luxembourg in the Context of Past Elections Högenauer, Anna-Lena E-print/Working paper (2019) The aim of this article is to analyse the 2019 European election in Luxembourg and to contextualize it by comparing it with past elections. The article presents the party landscape, the electoral campaign ... [more ▼] The aim of this article is to analyse the 2019 European election in Luxembourg and to contextualize it by comparing it with past elections. The article presents the party landscape, the electoral campaign, the electoral system and the results of the 2019 European election. The results are then analysed in the context of past national and European elections in order to establish whether European elections are second-order elections in Luxembourg, how electoral volatility evolved over time, whether there is a rise in Eurosceptic parties and how the representation of women has evolved since 1979. [less ▲] Detailed reference viewed: 18 (1 UL)The conformal group of a compact simply connected Lorentzian manifold ; Pecastaing, Vincent E-print/Working paper (2019) Detailed reference viewed: 96 (1 UL)Constant Gaussian curvature foliations and Schläfli formulas of hyperbolic 3-manifolds Mazzoli, Filippo E-print/Working paper (2019) We study the geometry of the foliation by constant Gaussian curvature surfaces (S_k)_k of a hyperbolic end, and how it relates to the structures of its boundary at infinity and of its pleated boundary ... [more ▼] We study the geometry of the foliation by constant Gaussian curvature surfaces (S_k)_k of a hyperbolic end, and how it relates to the structures of its boundary at infinity and of its pleated boundary. First, we show that the Thurston and the Schwarzian parametrizations are the limits of two families of parametrizations of the space of hyperbolic ends, defined by Labourie in 1992 in terms of the geometry of the leaves S_k. We give a new description of the renormalized volume using the constant curvature foliation. We prove a generalization of McMullen's Kleinian reciprocity theorem, which replaces the role of the Schwarzian parametrization with Labourie's parametrizations. Finally, we describe the constant curvature foliation of a hyperbolic end as the integral curve of a time-dependent Hamiltonian vector field on the cotangent space to Teichmüller space, in analogy to the Moncrief flow for constant mean curvature foliations in Lorenzian space-times. [less ▲] Detailed reference viewed: 28 (2 UL)Deconstructing Blockchains: A Comprehensive Survey on Consensus, Membership and Structure ; ; et al E-print/Working paper (2019) It is no exaggeration to say that since the introduction of Bitcoin, blockchains have become a disruptive technology that has shaken the world. However, the rising popularity of the paradigm has led to a ... [more ▼] It is no exaggeration to say that since the introduction of Bitcoin, blockchains have become a disruptive technology that has shaken the world. However, the rising popularity of the paradigm has led to a flurry of proposals addressing variations and/or trying to solve problems stemming from the initial specification. This added considerable complexity to the current blockchain ecosystems, amplified by the absence of detail in many accompanying blockchain whitepapers. Through this paper, we set out to explain blockchains in a simple way, taming that complexity through the deconstruction of the blockchain into three simple, critical components common to all known systems: membership selection, consensus mechanism and structure. We propose an evaluation framework with insight into system models, desired properties and analysis criteria, using the decoupled components as criteria. We use this framework to provide clear and intuitive overviews of the design principles behind the analyzed systems and the properties achieved. We hope our effort will help clarifying the current state of blockchain proposals and provide directions to the analysis of future proposals. [less ▲] Detailed reference viewed: 40 (1 UL)Distant Justice Symposium: Phil Clark’s ‘Distant Justice’–A Wake-Up Call for the International Criminal Court or a Case for Managing Expectations? Owiso, Owiso E-print/Working paper (2019) Detailed reference viewed: 32 (0 UL)Der Arbeitsmarkt der Sozialen Arbeit 2018 = Le marché de l'emploi du secteur social en 2018 Flammang, Manou Laure ; Böwen, Petra E-print/Working paper (2019) This newsletter describes the job market in the social work sector in Luxembourg in 2018. The data are derived from an ongoing research project by the "PraxisBüro" of the University of Luxembourg. The ... [more ▼] This newsletter describes the job market in the social work sector in Luxembourg in 2018. The data are derived from an ongoing research project by the "PraxisBüro" of the University of Luxembourg. The newsletter presents a selection of statistics concerning for example the most sought after qualification levels, the distribution of practice fields, the distribution of job offers in public, municipal, private and non-governmental organisations and the documented gap between the demand of social workers with a Bachelor diploma and the number of Bachelor diplomas issued in Luxembourg. [less ▲] Detailed reference viewed: 746 (70 UL)Projective and conformal closed manifolds with a higher-rank lattice action Pecastaing, Vincent E-print/Working paper (2019) We prove global results about actions of cocompact lattices in higher-rank simple Lie groups on closed manifolds endowed with either a projective class of connections or a conformal class of pseudo ... [more ▼] We prove global results about actions of cocompact lattices in higher-rank simple Lie groups on closed manifolds endowed with either a projective class of connections or a conformal class of pseudo-Riemannian metrics of signature (p,q), with min(p,q)>1. In the continuity of a recent article, provided that such a structure is locally equivalent to its model X, the main question treated here is the completeness of the associated (G,X)-structure. The similarities between the model spaces of non-Lorentzian conformal geometry and projective geometry make that lots of arguments are valid for both cases, and we expose the proofs in parallel. The conclusion is that in both cases, when the real-rank is maximal, the manifold is globally equivalent to either the model space X or its double cover. [less ▲] Detailed reference viewed: 26 (0 UL)Expediting in Two-Echelon Spare Parts Inventory Systems Drent, Melvin ; Arts, Joachim E-print/Working paper (2019) We consider a two-echelon spare parts inventory system consisting of one central warehouse and multiple local warehouses. Each warehouse keeps multiple types of repairable parts to maintain several types ... [more ▼] We consider a two-echelon spare parts inventory system consisting of one central warehouse and multiple local warehouses. Each warehouse keeps multiple types of repairable parts to maintain several types of capital goods. The local warehouses face Poisson demand and are replenished by the central warehouse. We assume that unsatisfied demand is backordered at all warehouses. Furthermore, we assume deterministic lead times for the replenishments of the local warehouses. The repair shop at the central warehouse has two repair options for each repairable part: a regular repair option and an expedited repair option. Both repair options have stochastic lead times. Irrespective of the repair option, each repairable part uses a certain resource for its repair. Assuming a dual-index policy at the central warehouse and base stock control at the local warehouses, an exact and efficient evaluation procedure for a given control policy is formulated. To find an optimal control policy, we look at the minimization of total investment costs under constraints on both the aggregate mean number of backorders per capital good type and the aggregate mean fraction of repairs that are expedited per repair resource. For this non-linear non-convex integer programming problem, we develop a greedy heuristic and an algorithm based on decomposition and column generation. Both solution approaches perform very well with average optimality gaps of 1.56 and 0.23 percent, respectively, across a large test bed of industrial size. Based on a case study at Netherlands Railways, we show how managers can significantly reduce the investment in repairable spare parts when dynamic repair policies are leveraged to prioritize repair of parts whose inventory is critically low. [less ▲] Detailed reference viewed: 345 (79 UL)Reducibility of n-ary semigroups: from quasitriviality towards idempotency ; Devillet, Jimmy ; Marichal, Jean-Luc et al E-print/Working paper (2019) Let $X$ be a nonempty set. Denote by $\mathcal{F}^n_k$ the class of associative operations $F\colon X^n\to X$ satisfying the condition $F(x_1,\ldots,x_n)\in\{x_1,\ldots,x_n\}$ whenever at least $k$ of the ... [more ▼] Let $X$ be a nonempty set. Denote by $\mathcal{F}^n_k$ the class of associative operations $F\colon X^n\to X$ satisfying the condition $F(x_1,\ldots,x_n)\in\{x_1,\ldots,x_n\}$ whenever at least $k$ of the elements $x_1,\ldots,x_n$ are equal to each other. The elements of $\mathcal{F}^n_1$ are said to be quasitrivial and those of $\mathcal{F}^n_n$ are said to be idempotent. We show that $\mathcal{F}^n_1=\cdots =\mathcal{F}^n_{n-2}\varsubsetneq\mathcal{F}^n_{n-1}\varsubsetneq\mathcal{F}^n_n$. The class $\mathcal{F}^n_1$ was recently characterized by Couceiro and Devillet \cite{CouDev}, who showed that its elements are reducible to binary associative operations. However, some elements of $\mathcal{F}^n_n$ are not reducible. In this paper, we characterize the class $\mathcal{F}^n_{n-1}\setminus\mathcal{F}^n_1$ and show that its elements are reducible. In particular, we show that each of these elements is an extension of an $n$-ary Abelian group operation whose exponent divides $n-1$. [less ▲] Detailed reference viewed: 59 (8 UL)Borders and the mobility of migrants in France Paraschivescu, Claudia ; Nienaber, Birte ; Oesch, Lucas E-print/Working paper (2019) This country report investigates the ways in which the border as a site of control interferes with asylum seekers’ and refugees’ mobility trajectories before, upon and after arrival in France. The ... [more ▼] This country report investigates the ways in which the border as a site of control interferes with asylum seekers’ and refugees’ mobility trajectories before, upon and after arrival in France. The interplay between borders and mobility plays a key role in the Common European Asylum System, the Schengen area and the Dublin regulation, which all have been affected by the 2015 so-called migration crisis. Based on in-depth qualitative interviews with thirteen migrants and ten institutional actors in the city of Metz, the overarching finding indicates that migrants’ movements evolve from geographical trajectories in order to reach a country of destination, to administrative trajectories, in order to become regularised in the host country. Furthermore, while physical borders have interfered with some informants’ migratory journeys, they have done so only by changing their trajectories, and, at times, the initial country of destination. Thus, they did not deter the migrants from reaching a safe country of destination. Once in Metz, the migrants become subject to administrative borders performed by state agents, such as the Préfecture and the French Agency for Immigration and Integration (OFII), as well as by private actors from the employment market. [less ▲] Detailed reference viewed: 25 (1 UL)Borders and the mobility of migrants in Luxembourg Paraschivescu, Claudia ; Nienaber, Birte ; Oesch, Lucas E-print/Working paper (2019) This country report sought to explore the border as a site of control and the ways in which it interferes with migrants’ (asylum seekers, refugees and rejected asylum seekers) trajectories before, upon ... [more ▼] This country report sought to explore the border as a site of control and the ways in which it interferes with migrants’ (asylum seekers, refugees and rejected asylum seekers) trajectories before, upon and after arrival in Luxembourg. To this end, it explored, through qualitative interviews with a total of 29 state and civil society actors and migrants, as well as ethnographic observation at Findel airport, Luxembourg’s only external border, the multiple conceptualisations and experiences of borders. It has identified that the suppression of internal controls within the Schengen area has been accompanied by a surge of controls within the member states, either at the stage of lodging an asylum claim, or at the street level, where migrants can be stopped and searched by police officers. Furthermore, the data showed that the migrants interviewed not only did they experience bordering practices during their interactions with public actors, but they were also subject to bordering during their interactions with private actors from the housing and employment market. The principal finding of this research with regards to the interplay between borders and the mobility of migrants is that cross-border mobility is commonplace, the migrants’ mobility practices reflecting the movements of the local population. As such, borders do not represent efficient mechanisms of control which can prevent migrants’ mobility trajectories. [less ▲] Detailed reference viewed: 28 (2 UL)Borders and the mobility of migrants in the EU and Turkey Paraschivescu, Claudia ; Nienaber, Birte ; Oesch, Lucas E-print/Working paper (2019) This comparative report investigates the ways in which the mobility of applicants for international protection, beneficiaries of international protection and irregular migrants intersect with the borders ... [more ▼] This comparative report investigates the ways in which the mobility of applicants for international protection, beneficiaries of international protection and irregular migrants intersect with the borders encountered during their trajectories before, during and after their arrival in six EU countries (Greece, Hungary, Germany, Luxembourg, France and Spain) and Turkey. After defining the concept of borders, this study contextualises the securitisation of EU external and internal borders, and it provides some background information on the CEAS and the Dublin Regulation, which are central to this research. Moreover, it engages with the legislative framework in place in the field of asylum in the seven countries on which this report draws. Based on qualitative interviews with a total of 96 asylum seekers, refugees and irregular migrants, as well as 94 state and non-state actors and ethnographic observation, the empirical part of the study explored the following aspects: experiences and conceptualisations of borders; mobility patterns and trajectories; the interplay between the Schengen zone and the Dublin system; the shortcomings of CEAS; as well as policies and experiences in the fields of housing and employment. The main finding of this comparative report is that while territorial borders cannot always impede human mobility, they are recreated within countries as administrative borders, which can encourage secondary movements. [less ▲] Detailed reference viewed: 30 (2 UL)Belgien und Deutschland: eine kleine Beziehungsgeschichte Brüll, Christoph E-print/Working paper (2019) Detailed reference viewed: 61 (4 UL)Regrouping for Justice: Could Regional Inter-Governmental Organisations Save International Criminal Justice? Owiso, Owiso E-print/Working paper (2019) Detailed reference viewed: 23 (0 UL)Bad representations and homotopy groups of Character Varieties Guerin, Clément ; ; E-print/Working paper (2019) Let G be a connected, reductive, complex affine algebraic group, and let Xr denote the moduli space of G-valued representations of a rank r free group. We first characterize the singularities in Xr ... [more ▼] Let G be a connected, reductive, complex affine algebraic group, and let Xr denote the moduli space of G-valued representations of a rank r free group. We first characterize the singularities in Xr resolving conjectures of Florentino-Lawton. In particular, we compute the codimension of the orbifold singular locus using facts about Borel-de Siebenthal groups. We then use this codimension to calculate some higher homotopy groups of the smooth locus of Xr, proving conjectures of Florentino-Lawton-Ramras. Lastly, using the earlier analysis of Borel-de Siebenthal groups, we prove a conjecture of Sikora about CI Lie groups. [less ▲] Detailed reference viewed: 56 (3 UL)Quasicircles and width of Jordan curves in CP1 ; ; et al E-print/Working paper (2019) We study a notion of "width" for Jordan curves in CP1, paying special attention to the class of quasicircles. The width of a Jordan curve is defined in terms of the geometry of its convex hull in ... [more ▼] We study a notion of "width" for Jordan curves in CP1, paying special attention to the class of quasicircles. The width of a Jordan curve is defined in terms of the geometry of its convex hull in hyperbolic three-space. A similar invariant in the setting of anti de Sitter geometry was used by Bonsante-Schlenker to characterize quasicircles amongst a larger class of Jordan curves in the boundary of anti de Sitter space. By contrast to the AdS setting, we show that there are Jordan curves of bounded width which fail to be quasicircles. However, we show that Jordan curves with small width are quasicircles. [less ▲] Detailed reference viewed: 25 (0 UL)Dual pairs in the Pin-group and duality for the corresponding spinorial representation Guerin, Clément ; ; E-print/Working paper (2019) In this paper, we give a complete picture of Howe correspondence for the setting (O(E,b),Pin(E,b),Π), where O(E,b) is an orthogonal group (real or complex), Pin(E,b) is the two-fold Pin-covering of O(E,b ... [more ▼] In this paper, we give a complete picture of Howe correspondence for the setting (O(E,b),Pin(E,b),Π), where O(E,b) is an orthogonal group (real or complex), Pin(E,b) is the two-fold Pin-covering of O(E,b), and Π is the spinorial representation of Pin(E,b). More precisely, for a dual pair (G,G′) in O(E,b), we determine explicitly the nature of its preimages (G̃,G′~) in Pin(E,b), and prove that apart from some exceptions, (G̃,G′~) is always a dual pair in Pin(E,b); then we establish the Howe correspondence for Π with respect to (G̃,G′~). [less ▲] Detailed reference viewed: 33 (3 UL)Refining transparency and responsible investment?: The case of EIB and sustainable finance Alexandraki, Chrysa E-print/Working paper (2019) On 8 January 2019, an action was brought before the Court of Justice of the European Union (hereafter CJEU) by an environmental law charity, ClientEarth (hereafter applicant) against a multilateral ... [more ▼] On 8 January 2019, an action was brought before the Court of Justice of the European Union (hereafter CJEU) by an environmental law charity, ClientEarth (hereafter applicant) against a multilateral development bank (hereafter MDB) and European institution, the European Investment Bank (hereafter EIB). The case concerns the financing by the bank of a biomass energy generating project in Northern Spain – Galicia -, of the cost of 60 million euros, followed by the bank’s refusal to refine its decision to finance the aforementioned investment, regardless the applicant’s request for an internal review of this decision on April 2018. The applicant bases the request for an internal review on alleged ‘errors in the assessment of the financing combined with the provision of minimal information regarding the funding decision’. The main claim brought by the applicant involves the annulment of EIB’s refusal to conduct an internal review and subject its decision to scrutiny, as requested under Article 10 of the Aarhus Regulation (hereafter Regulation), bringing into discussion implementation issues of both International and European law. [less ▲] Detailed reference viewed: 68 (25 UL)The dual volume of quasi-Fuchsian manifolds and the Weil-Petersson distance Mazzoli, Filippo E-print/Working paper (2019) Making use of the dual Bonahon-Schläfli formula, we prove that the dual volume of the convex core of a quasi-Fuchsian manifold M is bounded by an explicit constant, depending only on the topology of M ... [more ▼] Making use of the dual Bonahon-Schläfli formula, we prove that the dual volume of the convex core of a quasi-Fuchsian manifold M is bounded by an explicit constant, depending only on the topology of M, times the Weil-Petersson distance between the hyperbolic structures on the upper and lower boundary components of the convex core of M. [less ▲] Detailed reference viewed: 71 (1 UL)Regulating banks for the public? The dilemmas of prudential regulation Commain, Sébastien E-print/Working paper (2019) The regulation of banking activities present policymakers with a conundrum: while essential for a healthy and growing economy, they also present important risks of crises that affect all citizens ... [more ▼] The regulation of banking activities present policymakers with a conundrum: while essential for a healthy and growing economy, they also present important risks of crises that affect all citizens. Prudential regulation is intended to contain the risks while enabling the socially beneficial functions of banks, but the shadow of financial interests influence hangs over the regulatory process. Assessing the reality and extent of this influence, this paper argues, requires first to acquire asound understanding of the social costs and benefits of banking, and the capacity of regulation to promote social welfare. This paper then offers the reader a review of the main issues covered in the literature and suggests some lessons for the study of financial interest groups. [less ▲] Detailed reference viewed: 18 (0 UL)Insights into protein structural, physicochemical, and functional consequences of missense variants in 1,330 disease-associated human genes 693259 ; ; et al E-print/Working paper (2019) Inference of the structural and functional consequences of amino acid-altering missense variants is challenging and not yet scalable. Clinical and research applications of the colossal number of ... [more ▼] Inference of the structural and functional consequences of amino acid-altering missense variants is challenging and not yet scalable. Clinical and research applications of the colossal number of identified missense variants is thus limited. Here we describe the aggregation and analysis of large-scale genomic variation and structural biology data for 1,330 disease-associated genes. Comparing the burden of 40 structural, physicochemical, and functional protein features of altered amino acids with 3-dimensional coordinates, we found 18 and 14 features that are associated with pathogenic and population missense variants, respectively. Separate analyses of variants from 24 protein functional classes revealed novel function-dependent vulnerable features. We then devised a quantitative spectrum, identifying variants with higher pathogenic variant-associated features. Finally, we developed a web resource (MISCAST; http://miscast.broadinstitute.org/) for interactive analysis of variants on linear and tertiary protein structures. The biological impact of missense variants available through the webtool will assist researchers in hypothesizing variant pathogenicity and disease trajectories. [less ▲] Detailed reference viewed: 160 (1 UL)Futuristic Project Becoming a Reality: Self-Driving Cars in Luxembourg Vukovich, Lilla ; Vysotskaya, Volha E-print/Working paper (2019) Detailed reference viewed: 72 (16 UL)WHY IS THE MARKET SKEWNESS-RETURN RELATIONSHIP NEGATIVE? Lehnert, Thorsten E-print/Working paper (2019) Detailed reference viewed: 80 (3 UL)The provision of long-term credit and firm growth Leon, Florian E-print/Working paper (2019) This paper investigates whether a higher level of long-term credit provision affects the growth of small and young firms. Firm-level data from more than 20,000 firms in 62 countries are combined with a ... [more ▼] This paper investigates whether a higher level of long-term credit provision affects the growth of small and young firms. Firm-level data from more than 20,000 firms in 62 countries are combined with a new hand-collected database on short-term and long-term credit provided to the private sector. Using a difference-in-difference framework, our results indicate that, contrary to short-term credit, long-term credit does not stimulate growth of small and young firms. This finding is, at least partially, explained by the differential impact of short-term and long-term credit provision on small and young firms’ access to credit. While the provision of short-term credit alleviates credit constraints faced by small and young firms, a larger provision of longterm bank loans has an opposite impact. Our findings are in line with the hypothesis that an increase of long-term credit provision reflects a lender’s choice to provide more financing to existing clients (intensive margin) to the detriment of firms without previous access to finance (extensive margin). [less ▲] Detailed reference viewed: 69 (0 UL)Price Pressure and the Market Skewness Risk Premium Lehnert, Thorsten E-print/Working paper (2019) Detailed reference viewed: 42 (0 UL)Mitochondrial morphology provides a mechanism for energy buffering at synapses Garcia, Guadalupe Clara ; ; et al E-print/Working paper (2019) Mitochondria as the main energy suppliers of eukaryotic cells are highly dynamic organelles that fuse, divide and are transported along the cytoskeleton to ensure cellular energy homeostasis. While these ... [more ▼] Mitochondria as the main energy suppliers of eukaryotic cells are highly dynamic organelles that fuse, divide and are transported along the cytoskeleton to ensure cellular energy homeostasis. While these processes are well established, substantial evidence indicates that the internal structure is also highly variable in dependence on metabolic conditions. However, a quantitative mechanistic understanding of how mitochondrial morphology affects energetic states is still elusive. To address this question, we here present an agent-based dynamic model using three-dimensional morphologies from electron microscopy tomography which considers the molecular dynamics of the main ATP production components. We apply our modeling approach to mitochondria at the synapse which is the largest energy consumer within the brain. Interestingly, comparing the spatiotemporal simulations with a corresponding space-independent approach, we find minor space dependence when the system relaxes toward equilibrium but a qualitative difference in fluctuating environments. These results suggest that internal mitochondrial morphology is not only optimized for ATP production but also provides a mechanism for energy buffering and may represent a mechanism for cellular robustness. [less ▲] Detailed reference viewed: 75 (8 UL)Identification of pathogenic variant enriched regions across genes and gene families ; May, Patrick ; et al E-print/Working paper (2019) Missense variant interpretation is challenging. Essential regions for protein function are conserved among gene family members, and genetic variants within these regions are potentially more likely to ... [more ▼] Missense variant interpretation is challenging. Essential regions for protein function are conserved among gene family members, and genetic variants within these regions are potentially more likely to confer risk to disease. Here, we generated 2,871 gene family protein sequence alignments involving 9,990 genes and performed missense variant burden analyses to identify novel essential protein regions. We mapped 2,219,811 variants from the general population into these alignments and compared their distribution with 65,034 missense variants from patients. With this gene family approach, we identified 398 regions enriched for patient variants spanning 33,887 amino acids in 1,058 genes. As a comparison, testing the same genes individually we identified less patient variant enriched regions involving only 2,167 amino acids and 180 genes. Next, we selected de novo variants from 6,753 patients with neurodevelopmental disorders and 1,911 unaffected siblings, and observed a 5.56-fold enrichment of patient variants in our identified regions (95% C.I. =2.76-Inf, p-value = 6.66×10−8). Using an independent ClinVar variant set, we found missense variants inside the identified regions are 111-fold more likely to be classified as pathogenic in comparison to benign classification (OR = 111.48, 95% C.I = 68.09-195.58, p-value < 2.2e−16). All patient variant enriched regions identified (PERs) are available online through a user-friendly platform for interactive data mining, visualization and download at http://per.broadinstitute.org. In summary, our gene family burden analysis approach identified novel patient variant enriched regions in protein sequences. This annotation can empower variant interpretation. [less ▲] Detailed reference viewed: 66 (0 UL)Les Lorrains actifs à l'étranger, analyse au niveau communal Pigeron-Piroth, Isabelle ; Helfer, Malte E-print/Working paper (2019) A growing number of people living in Lorraine cross the border for work. Today, there are more than 100 000 commuters, the majority of them working in Luxembourg. The flow of commuters into Luxembourg is ... [more ▼] A growing number of people living in Lorraine cross the border for work. Today, there are more than 100 000 commuters, the majority of them working in Luxembourg. The flow of commuters into Luxembourg is on the increase, whereas commuting into Germany continues to shrink. The analysis of com-munes of residence shows a high proportion of cross-border commuters living as the active population in close vicinity to Luxembourg, but many also live in communes further afield; this phenomenon is moving beyond the borders and raises many issues: environmental, social and economic … [less ▲] Detailed reference viewed: 50 (4 UL)A Symbol of History Danescu, Elena E-print/Working paper (2019) As the fifth sovereign of the national dynasty since 1890, Grand Duke Jean was a head of state who perfectly embodied the ideals of service to his country and commitment to European integration. Detailed reference viewed: 22 (1 UL)Inexact Block Coordinate Descent Algorithms for Nonsmooth Nonconvex Optimization Yang, Yang ; ; et al E-print/Working paper (2019) In this paper, we propose an inexact block coordinate descent algorithm for large-scale nonsmooth nonconvex optimization problems. At each iteration, a particular block variable is selected and updated by ... [more ▼] In this paper, we propose an inexact block coordinate descent algorithm for large-scale nonsmooth nonconvex optimization problems. At each iteration, a particular block variable is selected and updated by solving the original optimization problem with respect to that block variable inexactly. More precisely, a local approximation of the original optimization problem is solved. The proposed algorithm has several attractive features, namely, i) high flexibility, as the approximation function only needs to be strictly convex and it does not have to be a global upper bound of the original function; ii) fast convergence, as the approximation function can be designed to exploit the problem structure at hand and the stepsize is calculated by the line search; iii) low complexity, as the approximation subproblems are much easier to solve and the line search scheme is carried out over a properly constructed differentiable function; iv) guaranteed convergence to a stationary point, even when the objective function does not have a Lipschitz continuous gradient. Interestingly, when the approximation subproblem is solved by a descent algorithm, convergence to a stationary point is still guaranteed even if the approximation subproblem is solved inexactly by terminating the descent algorithm after a finite number of iterations. These features make the proposed algorithm suitable for large-scale problems where the dimension exceeds the memory and/or the processing capability of the existing hardware. These features are also illustrated by several applications in signal processing and machine learning, for instance, network anomaly detection and phase retrieval. [less ▲] Detailed reference viewed: 95 (8 UL)LES IMPACTS ECONOMIQUES ET TERRITORIAUX DU TRAVAIL FRON-TALIER SUR LES TERRITOIRES DE RESIDENCE : L’exemple du bassin de Longwy ; Pigeron-Piroth, Isabelle E-print/Working paper (2019) This article questions the impacts of cross-border worker mobility on the economic and social devel-opment of their place of residence. We hypothesize that cross-border mobility produces resources for the ... [more ▼] This article questions the impacts of cross-border worker mobility on the economic and social devel-opment of their place of residence. We hypothesize that cross-border mobility produces resources for the worker, the enterprise and the territory, but it can also be a source of constraints. After a geo-graphical framework of the study, this article analyses the main positive territorial impacts of cross-border mobility. It shows that they contribute to the territorial dynamism of these border regions by attracting new sociological profiles of workers, by revitalizing rural territories (through housing), by limiting the increase of local unemployment and by encouraging a new form of in-place economy. Fi-nally, the paper also shows how such mobility can impede the own development of these border terri-tories, such as via a deeper local social stratification and a lack of highly qualified manpower. [less ▲] Detailed reference viewed: 55 (2 UL)Le travail frontalier au Luxembourg : éléments de contexte et de portrait statistique Pigeron-Piroth, Isabelle E-print/Working paper (2019) In Luxemburg, 44.4% of employees lives across the border and comes from the three neighboring coun-tries. Cross-border work has historic roots. It is a lasting, growing phenomenon, anchored in local econo ... [more ▼] In Luxemburg, 44.4% of employees lives across the border and comes from the three neighboring coun-tries. Cross-border work has historic roots. It is a lasting, growing phenomenon, anchored in local econo-mies. This contribution underlines the importance of contextual conditions under which these flows have in-creased. It presents the main characteristics and challenges of cross-border work in Luxembourg, in order to compare with Switzerland. [less ▲] Detailed reference viewed: 60 (4 UL)5. Forschungsbericht zur Weiterentwicklung des Arbeitsqualitätsindexes in Luxemburg Sischka, Philipp ; Steffgen, Georges E-print/Working paper (2019) Der „Quality of Work Index Luxembourg“ (QoW)-Survey, der von der Universität Luxemburg und der luxemburgischen Chambre des Salariés konzipiert wurde (Steffgen, Kohl, 2013; Sischka, Steffgen, 2015, 2016 ... [more ▼] Der „Quality of Work Index Luxembourg“ (QoW)-Survey, der von der Universität Luxemburg und der luxemburgischen Chambre des Salariés konzipiert wurde (Steffgen, Kohl, 2013; Sischka, Steffgen, 2015, 2016, 2017, 2019), wurde 2018 zum sechsten Mal durchgeführt. Ziel des Surveys ist es, die erlebte Arbeitssituation und -qualität luxemburgischer Arbeitnehmer zu erfassen. Der vorliegende Bericht dokumentiert die psychometrische Testung der Güte des aktuellen Erhebungsinstruments. In einem ersten Schritt erfolgt eine Beschreibung der Befragungsumstände sowie eine demographische Beschreibung der Stichprobe. Da die Erhebung 2018 als Mixed-Mode-Design – telefonische als auch Online-Befragung – durchgeführt wurde, wird auch analysiert, ob Stichprobenunterschiede zwischen den beiden Erhebungsmodi auftreten. Außerdem wird geklärt, ob es hinsichtlich demographischer Eigenschaften der Befragten, hinsichtlich der QoW-Skalen oder hinsichtlich verschiedener Well-Being-Maße zu systematischen Ausfällen seit der letzten Welle gekommen ist. Dann werden die Items der QoW- und Well-Being-Skalen auf fehlende Werte untersucht und es erfolgt eine Beschreibung der Items mittels verteilungsbeschreibender Maßzahlen und Balkendiagramme. In einem nächsten Schritt werden die Skalen mittels verschiedener Reliabilitätsstatistiken (Cronbach’s Alpha, Korrelationsanalysen der Items) sowie Koeffizienten zur Beschreibung der Skalenverteilung überprüft. Außerdem werden die Zusammenhänge der Skalen mittels Korrelationsanalysen überprüft. Im Anschluss daran wird die unterstellte Faktorenstruktur mittels konfirmatorischer Faktoren-analysen getestet. Die QoW-Skalen werden außerdem auf verschiedene Well-Being-Skalen regressiert, um deren Relevanz für den QoW-Index zu prüfen. Ebenso werden einige Längsschnitt-Regressionsanalysen durchgeführt, um zu überprüfen ob einige Arbeitsbedingungen längerfristige Effekte auf das Well-Being der Arbeitnehmer aufweisen. Die QoW-Befragung 2018 hat außerdem das Schwerpunktthema „Work-Life-Balance“ behandelt. Die Güte der Skalen zu diesem Thema wird ebenfalls geprüft. Im Anschluss werden dann Korrelationen mit den QoW- und Well-Being-Skalen berechnet. Abschließend wird das gesamte Erhebungsinstrument zusammenfassend diskutiert und Emp-fehlungen bezüglich zukünftiger Befragungen gegeben. [less ▲] Detailed reference viewed: 56 (6 UL)Les Lorrains actifs à l'étranger : une analyse cartographique au niveau communal Helfer, Malte ; Pigeron-Piroth, Isabelle E-print/Working paper (2019) A growing number of people living in Lorraine cross the border for work. Today, there are more than 100 000 commuters, the majority of them working in Luxembourg. The flow of commuters into Luxem-bourg is ... [more ▼] A growing number of people living in Lorraine cross the border for work. Today, there are more than 100 000 commuters, the majority of them working in Luxembourg. The flow of commuters into Luxem-bourg is on the increase, whereas commuting into Germany continues to shrink. The analysis of com-munes of residence shows a high proportion of cross-border commuters living as the active population in close vicinity to Luxembourg, but many also live in communes further afield; this phenomenon is moving beyond the borders and raises many issues: environmental, social and economic … [less ▲] Detailed reference viewed: 58 (7 UL)les travailleurs frontaliers au Luxembourg et en Suisse : Emploi, Quotidien et Perceptions Pigeron-Piroth, Isabelle ; Wille, Christian E-print/Working paper (2019) Petits pays ayant d’importants besoins de main-d’œuvre, le Luxembourg et la Suisse attirent tous deux un grand nombre de travailleurs frontaliers. C’est dans une perspective comparative que les 19 auteurs ... [more ▼] Petits pays ayant d’importants besoins de main-d’œuvre, le Luxembourg et la Suisse attirent tous deux un grand nombre de travailleurs frontaliers. C’est dans une perspective comparative que les 19 auteurs impliqués dans ce Cahier Thématique analysent la situation des travailleurs frontaliers dans les principaux pôles d’emploi transfrontaliers (Luxembourg, Bâle, Genève), mais également au Tessin. En tenant compte des éléments contextuels et méthodologiques, géographes, économistes, sociologues et politologues se focalisent sur les questions d’emploi, le quotidien transfrontalier et les perceptions des frontaliers par la société. Cette approche collective et pluridisciplinaire est résumée par les éditeurs en identifiant des enjeux communs pour le Luxembourg et la Suisse. [less ▲] Detailed reference viewed: 368 (46 UL)Déchiffrer le phénomène des travailleurs transfrontaliers en Suisse ; Wille, Christian ; Pigeron-Piroth, Isabelle E-print/Working paper (2019) Cross-border workers form a little-known but numerous population in Switzerland. Beyond clichés, this contribution brings together the main characteristics of this population based on official statistics ... [more ▼] Cross-border workers form a little-known but numerous population in Switzerland. Beyond clichés, this contribution brings together the main characteristics of this population based on official statistics and the latest research. The introduction of the Freedom of Movement Agreement did not change the growth trend of the population that remains to live and work in proximity of the border, mostly in France and near-Switzerland agglomerations. Conversely, the occupational areas and levels have diversified. Generally, cross-border workers have no negative influence on the labour market, except on salary level in some economic sectors in Ticino. The initiation of the “priority to Swiss residents” will not change the situation, which relates above all to the economic evolution. [less ▲] Detailed reference viewed: 72 (3 UL)BORDERS IN THE LIVES OF ASYLUM SEEKERS & REFUGEES IN LUXEMBOURG & METZ Paraschivescu, Claudia E-print/Working paper (2019) Detailed reference viewed: 59 (5 UL)To be or not to be: How the Luxembourgish government is preparing for Brexit Vysotskaya, Volha ; Vukovich, Lilla ; Bissinger, Jutta et al E-print/Working paper (2019) This article summarizes the potential impact of BREXIT on Luxembourg (as seen by April 2019). Detailed reference viewed: 80 (24 UL)Weshalb wechseln Arbeitnehmer ihren Arbeitgeber? Sischka, Philipp ; Steffgen, Georges E-print/Working paper (2019) 4,4% der Befragten des Quality of Work Survey hat zwischen den Erhebungen 2017 und 2018 den Arbeitgeber gewechselt. Vor allem die jüngsten Arbeitnehmer (16 bis 24 Jahre) sowie Arbeitnehmer mit einer ... [more ▼] 4,4% der Befragten des Quality of Work Survey hat zwischen den Erhebungen 2017 und 2018 den Arbeitgeber gewechselt. Vor allem die jüngsten Arbeitnehmer (16 bis 24 Jahre) sowie Arbeitnehmer mit einer befristeten Arbeitsstelle wechselten eher ihren Arbeitgeber. Je geringer Partizipation und Feedback, je höher Mobbing, und je geringer Einkommenszufriedenheit, Ausbildungs- und Beförderungsmöglichkeiten ausfallen, desto höher die Wahrscheinlichkeit eines Arbeitgeberwechsels. Arbeitnehmer, die den Arbeitgeber gewechselt haben, weisen dann im Mittel einen Zuwachs an Wohlbefinden auf. [less ▲] Detailed reference viewed: 38 (2 UL)Rank n swapping algebra for Grassmannian Sun, Zhe E-print/Working paper (2019) The rank n swapping algebra is the Poisson algebra defined on the ordered pairs of points on a circle using the linking numbers, where a subspace of (K^n×K^{n∗})^r/GL(n,K) is its geometric mode. In this ... [more ▼] The rank n swapping algebra is the Poisson algebra defined on the ordered pairs of points on a circle using the linking numbers, where a subspace of (K^n×K^{n∗})^r/GL(n,K) is its geometric mode. In this paper, we find an injective Poisson homomorphism from the Poisson algebra on Grassmannian G(n,r) arising from boundary measurement map to the rank n swapping fraction algebra. [less ▲] Detailed reference viewed: 36 (6 UL)Hyperideal polyhedra in the 3-dimensional anti-de Sitter space Chen, Qiyu ; Schlenker, Jean-Marc E-print/Working paper (2019) We study hyperideal polyhedra in the 3-dimensional anti-de Sitter space AdS3, which are defined as the intersection of the projective model of AdS3 with a convex polyhedron in RP3 whose vertices are all ... [more ▼] We study hyperideal polyhedra in the 3-dimensional anti-de Sitter space AdS3, which are defined as the intersection of the projective model of AdS3 with a convex polyhedron in RP3 whose vertices are all outside of AdS3 and whose edges all meet AdS3. We show that hyperideal polyhedra in AdS3 are uniquely determined by their combinatorics and dihedral angles, as well as by the induced metric on their boundary together with an additional combinatorial data, and describe the possible dihedral angles and the possible induced metrics on the boundary. [less ▲] Detailed reference viewed: 40 (2 UL)A Multi-agent approach for in silico simulations of micro-biological systems Proverbio, Daniele ; ; et al E-print/Working paper (2019) A Multi-agent approach forin silicosimulations ofmicro-biological systemsProverbio D., Gallo L., Passalacqua B., Pellegrino J., Maggiora M.AbstractUsing a Multi-agent systems paradigm, the present project ... [more ▼] A Multi-agent approach forin silicosimulations ofmicro-biological systemsProverbio D., Gallo L., Passalacqua B., Pellegrino J., Maggiora M.AbstractUsing a Multi-agent systems paradigm, the present project develops, validates and exploits a computa-tionaltestbedthat simulates micro-biological complex systems, namely the aggregation patterns of thesocial amoebaDyctiostelium discoideum. We propose a new design and implementation for managingdiscrete simulations with autonomous agents on a microscopic scale, thus focusing on their social be-havior and mutual interactions. Then, the dependence on the main physical variables is tested, namelydensity and number of amoebas; in addition, we analyze the robustness of the dynamics against var-ious noise sources. Along with these results, we suggest a methodology for further studies that makeuse of our validated model. [less ▲] Detailed reference viewed: 84 (4 UL)Single-cell transcriptomics reveals multiple neuronal cell types in human midbrain-specific organoids Smits, Lisa ; Magni, Stefano ; Grzyb, Kamil et al E-print/Working paper (2019) Human stem cell-derived organoids have great potential for modelling physiological and pathological processes. They recapitulate in vitro the organisation and function of a respective organ or part of an ... [more ▼] Human stem cell-derived organoids have great potential for modelling physiological and pathological processes. They recapitulate in vitro the organisation and function of a respective organ or part of an organ. Human midbrain organoids (hMOs) have been described to contain midbrain-specific dopaminergic neurons that release the neurotransmitter dopamine. However, the human midbrain contains also additional neuronal cell types, which are functionally interacting with each other. Here, we analysed hMOs at high-resolution by means of single-cell RNA-sequencing (scRNA-seq), imaging and electrophysiology to unravel cell heterogeneity. Our findings demonstrate that hMOs show essential neuronal functional properties as spontaneous electrophysiological activity of different neuronal subtypes, including dopaminergic, GABAergic, and glutamatergic neurons. Recapitulating these in vivo features makes hMOs an excellent tool for in vitro disease phenotyping and drug discovery. [less ▲] Detailed reference viewed: 195 (41 UL)Scalable Viewing. Digitale Methoden und die Digital Humanities Pause, Johannes ; Walkowski, Niels-Oliver E-print/Working paper (2019) Detailed reference viewed: 29 (3 UL)Energy policies for eco-friendly households in Luxembourg—a study based on the LuxHEI model Poncin, Stéphane Louis Maxim E-print/Working paper (2019) In the Grand Duchy of Luxembourg, the residential building sector is a major energy consumer and greenhouse gases emitter that is considered key in achieving the country's climate goals. The purpose of ... [more ▼] In the Grand Duchy of Luxembourg, the residential building sector is a major energy consumer and greenhouse gases emitter that is considered key in achieving the country's climate goals. The purpose of this paper is to assess the effectiveness of the most important policy instruments in achieving savings in the final energy consumption and direct CO2 emissions of Luxembourgish households. Our study is based on the LuxHEI model, which is an enhanced and upgraded version of the well-known French simulation model Res-IRF. This variant has been adjusted to the particular problems of a small country with growing economy and a quickly increasing population. The LuxHEI model goes beyond standard energy-economy models by incorporating global warming as a decision-making factor. The model outcomes reveal that total environmental and economic effectiveness increases if energy policy tools are applied concurrently. In 2060, and compared to the no-policy baseline scenario, the most aspirational policy mix enables energy savings of 42% and an emission mitigation of 60%. From our results we can draw the following policy implications: for a significant improvement of the sector's energy efficiency and sufficiency, (1) the implementation of a remediation duty for existing buildings and (2) the tightening of the performance standards for new constructions, (3) combined with a national carbon tax, are crucial. [less ▲] Detailed reference viewed: 147 (18 UL)Volumes of quasifuchsian manifolds Schlenker, Jean-Marc E-print/Working paper (2019) Quasifuchsian hyperbolic manifolds, or more generally convex co-compact hyperbolic manifolds, have infinite volume, but they have a well-defined ``renormalized'' volume. We outline some relations between ... [more ▼] Quasifuchsian hyperbolic manifolds, or more generally convex co-compact hyperbolic manifolds, have infinite volume, but they have a well-defined ``renormalized'' volume. We outline some relations between this renormalized volume and the volume, or more precisely the ``dual volume'', of the convex core. On one hand, there are striking similarities between them, for instance in their variational formulas. On the other, object related to them tend to be within bounded distance. Those analogies and proximities lead to several questions. Both the renormalized volume and the dual volume can be used for instance to bound the volume of the convex core in terms of the Weil-Petersson distance between the conformal metrics at infinity. [less ▲] Detailed reference viewed: 35 (1 UL)4. Forschungsbericht zur Weiterentwicklung des Arbeitsqualitätsindexes in Luxemburg Sischka, Philipp ; Steffgen, Georges E-print/Working paper (2019) Der Survey zu dem „Quality of Work Index Luxembourg“ (QoW), der von der Universität Luxemburg und der luxemburgischen Chambré des Salariés entwickelt wurde (Steffgen, Kohl, 2013; Sischka, Steffgen, 2015 ... [more ▼] Der Survey zu dem „Quality of Work Index Luxembourg“ (QoW), der von der Universität Luxemburg und der luxemburgischen Chambré des Salariés entwickelt wurde (Steffgen, Kohl, 2013; Sischka, Steffgen, 2015, 2016, 2017), wurde 2017 bereits zum fünften Mal mittels einer telefonischen Befragung durchgeführt. Ziel des Index ist es, die erlebte Arbeitssituation und -qualität luxemburgischer Arbeitnehmer zu erfassen. Der vorliegende Bericht dokumentiert die psychometrische Testung der Güte des aktuellen Erhebungsinstruments. Dazu erfolgt zunächst eine Beschreibung der für die Skalen genutzten Items, die Überprüfung der internen Konsistenz der jeweiligen Skala mittels verschiedener Reliabilitätsstatistiken (Cronbach’s Alpha, Korrelationsanalysen der Items) sowie Koeffizienten zur Beschreibung der Skalenverteilung. Konfirmatorische Faktorenanalysen dienen dazu, zu testen, ob die Items auf den a priori festgelegten Faktoren laden und ob sich die unterstellte Faktorenstruktur auch in den Daten zeigt. Außerdem werden die Zusammenhänge der Skalen mittels Korrelationsanalysen über-prüft. Die QoW-Skalen werden außerdem auf verschiedene Well-Being-Skalen regressiert, um deren Relevanz für den QoW-Index zu prüfen. Da der QoW Survey teilweise als Panelbefragung durchgeführt wird, wird außerdem geklärt, ob es hinsichtlich demographischer Eigenschaften der Befragten, hinsichtlich der QoW-Skalen oder hinsichtlich verschiedener Well-Being-Maße zu systematischen Ausfällen seit der letzten Welle gekommen ist. Ebenso werden einige Längsschnitt-Regressionsanalysen gerechnet, um zu überprüfen, ob einige Arbeitsbedingungen längerfristige Effekte auf das Well-Being der Arbeitnehmer aufweisen. Die QoW-Befragung 2017 hat außerdem das Schwerpunktthema „Digitalisierung“ behandelt. Die Themenblöcke werden mittels Latenter Profile-Analysen untersucht. Im Anschluss wird überprüft ob sich die extrahierten Profile hinsichtlich der QoW- und der Well-Being-Skalen unterscheiden. Abschließend wird das gesamte Erhebungsinstrument zusammenfassend diskutiert und Empfehlungen bezüglich der weiteren Entwicklung der Skalen gegeben. [less ▲] Detailed reference viewed: 22 (0 UL)Automobile, sport et tourisme. Le Grand Prix de la Marne dans le calendrier européen (1925-1939) Moreau, Sebastien E-print/Working paper (2019) Depuis le début du xxe siècle, notamment à l’occasion des coupes Gordon-Bennett (1900), c’est sous les projecteurs d’une presse cocardière, complice et friande de modernité technique que les constructeurs ... [more ▼] Depuis le début du xxe siècle, notamment à l’occasion des coupes Gordon-Bennett (1900), c’est sous les projecteurs d’une presse cocardière, complice et friande de modernité technique que les constructeurs automobiles présentent, sur la scène européenne, les performances de leurs bolides. Au lendemain de la Première Guerre mondiale, alors que le parc automobile et les flux touristiques croissent de façon vertigineuse, les courses automobiles se multiplient. Un championnat d’Europe est organisé en 1925 par la Commission sportive internationale de l’Association internationale des automobile-clubs reconnus (AIACR) qui s’appuie sur des initiatives locales. Pour les organisateurs locaux de courses, inscrire son circuit dans le calendrier du championnat d’Europe devient un enjeu majeur. Soutenus par les commerçants, industriels et édiles politiques locaux, les organisateurs saisissent l’occasion de la course pour faire de la publicité et stimuler l’économie. Partout en Europe, des acteurs locaux se mobilisent en ce sens pour tirer profit et prestige des circulations plurielles qu’engendre le sport automobile européen. Le cas du Grand Prix de la Marne illustre parfaitement l’enchevêtrement des échelles qui caractérise, du local à l’international, l’émergence d’une scène et d’un public européens pour les spectacles sportifs automobiles [less ▲] Detailed reference viewed: 36 (3 UL)Taxonomien computergestützter Forschung. Digitale Methoden und die Digital Humanities Pause, Johannes ; Walkowski, Niels-Oliver E-print/Working paper (2019) Detailed reference viewed: 38 (2 UL)The induced metric on the boundary of the convex hull of a quasicircle in hyperbolic and anti de Sitter geometry ; ; et al E-print/Working paper (2019) Celebrated work of Alexandrov and Pogorelov determines exactly which metrics on the sphere are induced on the boundary of a compact convex subset of hyperbolic three-space. As a step toward a ... [more ▼] Celebrated work of Alexandrov and Pogorelov determines exactly which metrics on the sphere are induced on the boundary of a compact convex subset of hyperbolic three-space. As a step toward a generalization for unbounded convex subsets, we consider convex regions of hyperbolic three-space bounded by two properly embedded disks which meet at infinity along a Jordan curve in the ideal boundary. In this setting, it is natural to augment the notion of induced metric on the boundary of the convex set to include a gluing map at infinity which records how the asymptotic geometry of the two surfaces compares near points of the limiting Jordan curve. Restricting further to the case in which the induced metrics on the two bounding surfaces have constant curvature Kâˆˆ[âˆ’1,0) and the Jordan curve at infinity is a quasicircle, the gluing map is naturally a quasisymmetric homeomorphism of the circle. The main result is that for each value of K, every quasisymmetric map is achieved as the gluing map at infinity along some quasicircle. We also prove analogous results in the setting of three-dimensional anti de Sitter geometry. Our results may be viewed as universal versions of the conjectures of Thurston and Mess about prescribing the induced metric on the boundary of the convex core of quasifuchsian hyperbolic manifolds and globally hyperbolic anti de Sitter spacetimes. [less ▲] Detailed reference viewed: 34 (2 UL)Rank n swapping algebra for PGLn Fock--Goncharov X moduli space Sun, Zhe E-print/Working paper (2019) The rank n swapping algebra is a Poisson algebra defined on the set of ordered pairs of points of the circle using linking numbers, whose geometric model is given by a certain subspace of (K^n×K^{n∗})^r ... [more ▼] The rank n swapping algebra is a Poisson algebra defined on the set of ordered pairs of points of the circle using linking numbers, whose geometric model is given by a certain subspace of (K^n×K^{n∗})^r/GL(n,K). For any ideal triangulation of D_k---a disk with k points on its boundary, using determinants, we find an injective Poisson algebra homomorphism from the fraction algebra generated by the Fock--Goncharov coordinates for X_{PGL_n,D_k} to the rank n swapping multifraction algebra for r=k⋅(n−1) with respect to the (Atiyah--Bott--)Goldman Poisson bracket and the swapping bracket. This is the building block of the general surface case. Two such injective Poisson algebra homomorphisms related to two ideal triangulations T and T′ are compatible with each other under the flips. [less ▲] Detailed reference viewed: 55 (6 UL)Corporate Governance and Skewness in Stock Returns ; Lehnert, Thorsten ; E-print/Working paper (2019) This paper analyzes the relationship between corporate governance and idiosyncratic skewness of stock returns. We test this hypothesis by analyzing the impact of external as well as internal governance ... [more ▼] This paper analyzes the relationship between corporate governance and idiosyncratic skewness of stock returns. We test this hypothesis by analyzing the impact of external as well as internal governance provisions, and are thus able to provide an overall understanding of the relationship between governance and firm-specific return asymmetries. Our results show that better governance leads to a reduction in idiosyncratic skewness in relatively non-competitive industries. In relatively competitive industries, governance has less to no impact on firm-specific return skewness. Furthermore, an overall increase in transparency, quality and disclosure of information, proxied through the Sarbanes Oxley Act, reduces relative idiosyncratic skewness. Our findings can be regarded as detrimental for shareholders, who have a preference for positive idiosyncratic skewness. The evidence contributes to a debate, which suggests that – at the end of the day – an act like Sarbanes-Oxley, which was intended to protect shareholders from accounting errors and frauds and to improve the accuracy of corporate disclosures, comes at the expenses of shareholders. The reduction of idiosyncratic skewness through better governance collides with shareholder’s preference for idiosyncratic and positively skewed stock returns, which present a lottery like upside option of monetary gains and value creation through the right tail. This side effect of governance is also in line with the literature that highlights potential costs of corporate governance. [less ▲] Detailed reference viewed: 63 (1 UL)COP 24 and Climate Finance: A Stepping Stone or a Blurred Line? Alexandraki, Chrysa E-print/Working paper (2019) In December 2018, the 24th Conference of the Parties (COP 24) to the United Nations Framework Convention on Climate Change (UNFCCC), took place in Katowice, Poland. The main objective of those ... [more ▼] In December 2018, the 24th Conference of the Parties (COP 24) to the United Nations Framework Convention on Climate Change (UNFCCC), took place in Katowice, Poland. The main objective of those negotiations was to finalize the so called ‘Paris Rulebook’ [the Paris Agreement Work Programme (PAWP)], which would constitute a set of rules to implement and operationalize the Paris Agreement. The issues at stakes varied from mitigation, adaptation and loss and damage, to more technical issues, such as transparency, climate finance and carbon market mechanisms under the Paris Agreement. This post focuses on the progress made on the issue of climate finance based on an analysis of the COP 24 decision on the relevant issues. [less ▲] Detailed reference viewed: 139 (29 UL)A System and Method for Monitoring Controlling and Troubleshooting of Abrasive Waterjet Cutting Apparatus Copertaro, Edoardo E-print/Working paper (2019) The invention consists of a system and method for monitoring, controlling and troubleshooting of Abrasive Waterjet Cutting machinery. More in detail, the method exploits a network of sensors for ... [more ▼] The invention consists of a system and method for monitoring, controlling and troubleshooting of Abrasive Waterjet Cutting machinery. More in detail, the method exploits a network of sensors for continuously monitor its vibroacoustic emission pattern. Relevant features are extracted from the data using an iterative processing method. Deviations from a benchmark are interpreted based on model training then used for automatic control and troubleshooting. The expected outcome is an improvement of waterjet automation and robustness to the excellence of Industry 4.0 with a consequent impact on both its cost effectiveness and the provided quality assurance. [less ▲] Detailed reference viewed: 80 (8 UL)Follow the Money, If You Can - Possible Solutions for Enhanced FIU Cooperation Under Improved Data Protection Rules Quintel, Teresa Alegra E-print/Working paper (2019) Financial information can play a key role in tackling Money Laundering (ML), Terrorist Financing (TF) and combatting serious crime more generally. Preventing and fighting ML and the financing of terrorism ... [more ▼] Financial information can play a key role in tackling Money Laundering (ML), Terrorist Financing (TF) and combatting serious crime more generally. Preventing and fighting ML and the financing of terrorism were top priorities of the European Agenda on Security, which might explain the fast developments regarding the regulation of Anti-Money Laundering (AML) and Counter Terrorism Financing (CTF). During the past years, the European Commission (Commission) proposed several legal texts to reform the current AML framework and to facilitate timely law enforcement (LE) access to financial data for the prevention, detection, investigation and prosecution of serious crime. The line between administrative sanctions and criminal law measures seems to become increasingly blurred, as the latest proposals are no longer based on an internal market provision, but on police and judicial cooperation legal bases. Financial Intelligence Units (FIUs) play a crucial role in analysing and exchanging information concerning suspicious transactions, serving as intermediaries between the private sector and Law Enforcement Authorities (LEAs). Because of the international nature of financial crime, cooperation between FIUs is of paramount importance. Yet, due to different organizational settings in the EU Member States, FIUs are not always able to exchange data effectively, which leads to information gaps. One of the reasons why the data exchange between FIUs is impeded are data protection rules that apply differently depending on the organizational structure of the FIUs in the 28 Member States. Whereas some FIUs must adhere to the stricter data protection rules under the General Data Protection Regulation (GDPR), others may exchange data more flexibly within the scope of the data protection Directive for police and criminal justice authorities (LED). Therefore, the counter-argument to granting broader LE-access rights to financial data by LEAs could be to enable a more effective exchange of data between FIUs. This article argues that FIUs should be able to process personal data within the scope of the LED, in order to have more flexibility to receive, analyse and exchange data: On the one hand, the LED provides sufficiently high data protection standards and adequate safeguards for data subjects while allowing FIUs to carry out their tasks effectively under harmonized rules. On the other hand, this would be an argument to strengthening the role of FIUs as neutral intermediaries instead of granting additional access to personal data by LEAs. [less ▲] Detailed reference viewed: 94 (4 UL)McShane identities for Higher Teichmüller theory and the Goncharov-Shen potential Sun, Zhe ; E-print/Working paper (2019) In [GS15], Goncharov and Shen introduce a family of mapping class group invariant regular functions on their A-moduli space to explicitly formulate a particular homological mirror symmetry conjecture ... [more ▼] In [GS15], Goncharov and Shen introduce a family of mapping class group invariant regular functions on their A-moduli space to explicitly formulate a particular homological mirror symmetry conjecture. Using these regular functions, we obtain McShane identities general rank positive surface group representations with loxodromic boundary monodromy and (non-strict) McShane-type inequalities for general rank positive representations with unipotent boundary monodromy. Our identities are expressed in terms of projective invariants, and we study these invariants: we establish boundedness and Fuchsian rigidity results for triple ratios. Moreover, we obtain McShane identities for finite-area cusped convex real projective surfaces by generalizing the Birman--Series geodesic scarcity theorem. We apply our identities to derive the simple spectral discreteness of unipotent bordered positive representations, collar lemmas, and generalizations of the Thurston metric. [less ▲] Detailed reference viewed: 35 (5 UL)Conformal actions of higher-rank lattices on pseudo-Riemannian manifolds Pecastaing, Vincent E-print/Working paper (2019) We investigate conformal actions of cocompact lattices in higher-rank simple Lie groups on compact pseudo-Riemannian manifolds. Our main result gives a general bound on the real-rank of the lattice, which ... [more ▼] We investigate conformal actions of cocompact lattices in higher-rank simple Lie groups on compact pseudo-Riemannian manifolds. Our main result gives a general bound on the real-rank of the lattice, which was already known for the action of the full Lie group ([33]). When the real-rank is maximal, we prove that the manifold is conformally flat. This indicates that a global conclusion similar to that of [1] and [17] in the case of a Lie group action might be obtained. We also give better estimates for actions of cocompact lattices in exceptional groups. Our work is strongly inspired by the recent breakthrough of Brown, Fisher and Hurtado on Zimmer’s conjecture [7]. [less ▲] Detailed reference viewed: 40 (2 UL)The Schwarz-Voronov embedding of Z_2^n - manifolds Bruce, Andrew ; Ibarguengoytia, Eduardo ; Poncin, Norbert E-print/Working paper (2019) Detailed reference viewed: 65 (8 UL)Les pratiques du quotidien transfrontalières dans la Grande Région SaarLorLux Wille, Christian E-print/Working paper (2019) This paper analyses everyday practices carried out by the residents of the Saarland, Lorraine, Luxembourg, Rhineland-Palatinate and Wallonia in the neighbouring regions abroad. The key assumption is the ... [more ▼] This paper analyses everyday practices carried out by the residents of the Saarland, Lorraine, Luxembourg, Rhineland-Palatinate and Wallonia in the neighbouring regions abroad. The key assumption is the consider-ation that the inhabitants of the Greater Region SaarLorLux define the transborder reality of life of this region through their cross-border performance of everyday practices. Such a socio-constructivist perspective is not interested in what the Greater Region SaarLorLux actually is, but in what ways it is constituted or how it manifests itself in the daily lives of its inhabitants. Therefor the most common cross-border everyday prac-tices, such as shopping for everyday needs, leisure-time shopping, outdoor recreation / tourism, cultural events, as well as visiting friends and family are looked at in greater detail. These observations are based on selected findings from three recent empirical studies of the study region, which have been linked to each other as well as socio-culturally and socioeconomically mapped in order to carve out the spatial organiza-tion, the motives and other contextual factors of cross-border everyday practices in the Greater Region SaarLorLux. This approach allows reconstructing mobility flows and spatial emphases in the context of everyday practices and gives insights into the nature of cross-border living realities in the Greater Region SaarLorLux. [less ▲] Detailed reference viewed: 149 (13 UL)ApproXON: Heuristic Approximation to the E-Field-Threshold for Deep Brain Stimulation Volume-of-Tissue-Activated Estimation Proverbio, Daniele ; Husch, Andreas E-print/Working paper (2019) This paper introduces a heuristic approximation of the e-field threshold used for volume-of-tissue activated computation in deep brain stimulation. Pulse width and axon diameter are used as predictors. An ... [more ▼] This paper introduces a heuristic approximation of the e-field threshold used for volume-of-tissue activated computation in deep brain stimulation. Pulse width and axon diameter are used as predictors. An open source implementation in MATLAB is provided together with an integration in the open LeadDBS deep brain stimulation research toolbox. [less ▲] Detailed reference viewed: 21 (0 UL)The Crowdsourced Replication Initiative: Investigating Immigration and Social Policy Preferences. Executive Report. ; ; et al E-print/Working paper (2019) In an era of mass migration, social scientists, populist parties and social movements raise concerns over the future of immigration-destination societies. What impacts does this have on policy and social ... [more ▼] In an era of mass migration, social scientists, populist parties and social movements raise concerns over the future of immigration-destination societies. What impacts does this have on policy and social solidarity? Comparative cross-national research, relying mostly on secondary data, has findings in different directions. There is a threat of selective model reporting and lack of replicability. The heterogeneity of countries obscures attempts to clearly define data-generating models. P-hacking and HARKing lurk among standard research practices in this area.This project employs crowdsourcing to address these issues. It draws on replication, deliberation, meta-analysis and harnessing the power of many minds at once. The Crowdsourced Replication Initiative carries two main goals, (a) to better investigate the linkage between immigration and social policy preferences across countries, and (b) to develop crowdsourcing as a social science method. The Executive Report provides short reviews of the area of social policy preferences and immigration, and the methods and impetus behind crowdsourcing plus a description of the entire project. Three main areas of findings will appear in three papers, that are registered as PAPs or in process. [less ▲] Detailed reference viewed: 297 (31 UL)UC Updatable Non-Hiding Committed Database with Efficient Zero-Knowledge Proofs Rial Duran, Alfredo E-print/Working paper (2019) We define an ideal functionality $\Functionality_{\DB}$ and a protocol $\mathrm{\Pi_{\DB}}$ for an updatable non-hiding committed database ($\DB$). $\DB$ is described as the task of storing a database ... [more ▼] We define an ideal functionality $\Functionality_{\DB}$ and a protocol $\mathrm{\Pi_{\DB}}$ for an updatable non-hiding committed database ($\DB$). $\DB$ is described as the task of storing a database into a suitable data structure that allows you to efficiently prove in zero-knowledge (ZK) that a value is stored in the database at a certain position. The database is \emph{non-hiding} because both prover and verifier know its content. It is \emph{committed} in the sense that only ZK proofs about position-value pairs that are actually stored are possible. It is \emph{updatable} because its contents can be modified dynamically throughout the protocol execution. The $\DB$ task is used implicitly as building block of privacy-preserving protocols for e-commerce, smart billing and access control. In those protocols, this task is intertwined with others. Our functionality $\Functionality_{\DB}$ allows us to study constructions for this task in isolation. Furthermore, it allows us to improve modularity in protocol design, by using $\Functionality_{\DB}$ as building block of those protocols along with functionalities for other tasks. Our construction $\mathrm{\Pi_{\DB}}$ uses a non-hiding vector commitment (VC) scheme as building block. Thanks to the efficiency properties of non-hiding VC schemes, $\mathrm{\Pi_{\DB}}$ provides ZK proofs whose computation cost (after initialization) and whose size are both independent of the database size. Therefore, $\mathrm{\Pi_{\DB}}$ is suitable for large databases. Moreover, the database can be updated dynamically and very efficiently. [less ▲] Detailed reference viewed: 81 (23 UL)Concise UC Zero-Knowledge Proofs for Oblivious Updatable Databases ; ; Rial Duran, Alfredo E-print/Working paper (2019) We propose an ideal functionality $\Functionality_{\COMD}$ and a construction for oblivious and updatable committed databases. $\Functionality_{\COMD}$ allows a prover to read, write, and update values in ... [more ▼] We propose an ideal functionality $\Functionality_{\COMD}$ and a construction for oblivious and updatable committed databases. $\Functionality_{\COMD}$ allows a prover to read, write, and update values in a database and to prove to a verifier in zero-knowledge that a value is read from or written into a certain position. The following properties must hold: (1) values stored in the database remain hidden from the verifier; (2) a value read from a certain position is equal to the value previously written into that position; (3) (obliviousness) both the value read or written and its position remain hidden from the verifier. We describe a construction for $\Functionality_{\COMD}$ based on vector commitments. After the initialization phase, the cost of zero-knowedge proofs for reading and writing is independent of the database size, outperforming other techniques that achieve cost sublinear in the dataset size for prover and/or verifier. Therefore, our construction is especially appealing for cases with large datasets. Finally, we show how to use $\Functionality_{\COMD}$ as a building block in ``commit-and-prove'' two-party protocols, i.e.\ protocols where the prover commits to her inputs and subsequently proves in zero-knowledge statements about the committed values. In comparison to simply using commitment schemes, our construction allows the prover to hide positions read or written efficiently, which is useful to design protocols for e.g.\ cloud-based services, blockchain, privacy-preserving location sharing services and e-commerce, and efficient OR proofs. [less ▲] Detailed reference viewed: 101 (7 UL)Household credit and growth: International evidence Leon, Florian E-print/Working paper (2019) This paper has two main objectives. First, it attempts to distinguish the effects of household and enterprise credit on economic growth for a large sample of developing and developed countries. Second, it ... [more ▼] This paper has two main objectives. First, it attempts to distinguish the effects of household and enterprise credit on economic growth for a large sample of developing and developed countries. Second, it investigates the channels through which household credit affects economic growth. To do so, a new database covering 143 countries over the period 1995-2014 is employed. Econometric results show that household credit has a negative effect on growth, while business credit has a positive, albeit non significant, impact on growth. The literature provide two possible explanations to justify the negative effect of household credit. On the one hand, household credit expansion can induce more financial fragility. On the other hand, the negative impact of household credit could be explained by its effect on saving behaviors. Results provide some evidence indicating that the negative effect of household credit is more driven by the latter than the former. [less ▲] Detailed reference viewed: 76 (0 UL)The War of Rare Earth Elements: A Dynamic Games Approach Bertinelli, Luisito ; Poncin, Stéphane Louis Maxim ; Zou, Benteng E-print/Working paper (2019) Rare earth elements govern today’s high-tech world and are deemed to be essential for the attainment of sustainable development goals. Since the 1990s, these elements have been predominantly supplied by ... [more ▼] Rare earth elements govern today’s high-tech world and are deemed to be essential for the attainment of sustainable development goals. Since the 1990s, these elements have been predominantly supplied by one single actor, China. However, due to the increasing global relevance of their availability, other countries are now encouraged to enter the market. The objective of this paper is to analyze the strategic interactions among (potential) suppliers. In particular, we are interested in (1) the optimal timing for a newcomer (e.g. the U.S.) to enter the market, (2) the incumbent’s (i.e. China’s) optimal behavior, and (3) the cost-efficiency of cooperative vs. competitive market relations. By setting up a continuous-time dynamic game model, we show that (1) the newcomer should postpone the production launch until its rare earth reserves coincide with those of the incumbent, (2) the incumbent should strive for a late market entry and therefore keep its monopolistic resource extraction at the lowest possible level, (3) compared to the payoffs under competition, cooperation leads to a Pareto improvement when started at an early stage. The findings of our model are particularly relevant for the rational strategic positioning of the two great powers, America and China. [less ▲] Detailed reference viewed: 57 (7 UL)Galois families of modular forms and application to weight one ; ; Wiese, Gabor E-print/Working paper (2019) We introduce Galois families of modular forms. They are a new kind of family coming from Galois representations of the absolute Galois groups of rational function fields over the rational field. We ... [more ▼] We introduce Galois families of modular forms. They are a new kind of family coming from Galois representations of the absolute Galois groups of rational function fields over the rational field. We exhibit some examples and provide an infinite Galois family of non-liftable weight one Katz modular eigenforms over an algebraic closure of F_p for p in {3,5,7,11}. [less ▲] Detailed reference viewed: 32 (0 UL)Ephemeral persistence modules and distance comparison ; Petit, François E-print/Working paper (2019) We provide a definition of ephemeral multi-persistent modules and prove that the quotient of persistent modules by the ephemeral ones is equivalent to the category of γ-sheaves. In the case of one ... [more ▼] We provide a definition of ephemeral multi-persistent modules and prove that the quotient of persistent modules by the ephemeral ones is equivalent to the category of γ-sheaves. In the case of one-dimensional persistence, our definition agrees with the usual one showing that the observable category and the category of γ-sheaves are equivalent. We also establish isometry theorems between the category of persistent modules and γ-sheaves both endowed with their interleaving distance. Finally, we compare the interleaving and convolution distances. [less ▲] Detailed reference viewed: 32 (0 UL)Differential graded Lie groups and their differential graded Lie algebras ; ; Poncin, Norbert et al E-print/Working paper (2019) Detailed reference viewed: 39 (2 UL)Linear system identification from ensemble snapshot observations Aalto, Atte ; Goncalves, Jorge E-print/Working paper (2019) Developments in transcriptomics techniques have caused a large demand in tailored computational methods for modelling gene expression dynamics from experimental data. Recently, so-called single-cell ... [more ▼] Developments in transcriptomics techniques have caused a large demand in tailored computational methods for modelling gene expression dynamics from experimental data. Recently, so-called single-cell experiments have revolutionised genetic studies. These experiments yield gene expression data in single cell resolution for a large number of cells at a time. However, the cells are destroyed in the measurement process, and so the data consist of snapshots of an ensemble evolving over time, instead of time series. The problem studied in this article is how such data can be used in modelling gene regulatory dynamics. Two different paradigms are studied for linear system identification. The first is based on tracking the evolution of the distribution of cells over time. The second is based on the so-called pseudotime concept, identifying a common trajectory through the state space, along which cells propagate with different rates. Therefore, at any given time, the population contains cells in different stages of the trajectory. Resulting methods are compared in numerical experiments. [less ▲] Detailed reference viewed: 73 (10 UL)An introduction to the theory of unconditionally secure message authentication using the constructive cryptography framework Ostrev, Dimiter E-print/Working paper (2019) We provide an introduction to certain ideas from the theory of unconditionally secure message authentication. We explain the notions of impersonation and substitution attacks, and explain how protection ... [more ▼] We provide an introduction to certain ideas from the theory of unconditionally secure message authentication. We explain the notions of impersonation and substitution attacks, and explain how protection against these two types of attack implies composable, information theoretic security. We explain the relation of authentication protocols to universal hashing. We give both probabilistic and explicit constructions proving the existence of one way authentication protocols using a short secret key and we prove matching lower bounds on the required secret key size. Then, we turn attention to interactive authentication protocols. We explain the message size reduction technique used by Gemmell and Naor and later Naor, Segev and Smith, and how it leads to protocols with secret key size independent of the message length. We also prove a matching lower bound on the secret key entropy. We generalize the lower bound proof of Naor, Segev and Smith and remove the assumption that the message is revealed in the first flow of the protocol. [less ▲] Detailed reference viewed: 71 (11 UL)Minimizing immersions of a hyperbolic surface in a hyperbolic 3-manifold ; ; Schlenker, Jean-Marc E-print/Working paper (2019) Let (S,h) be a closed hyperbolic surface and M be a quasi-Fuchsian 3-manifold. We consider incompressible maps from S to M that are critical points of an energy functional F which is homogeneous of degree ... [more ▼] Let (S,h) be a closed hyperbolic surface and M be a quasi-Fuchsian 3-manifold. We consider incompressible maps from S to M that are critical points of an energy functional F which is homogeneous of degree 1. These ``minimizing'' maps are solutions of a non-linear elliptic equation, and reminiscent of harmonic maps -- but when the target is Fuchsian, minimizing maps are minimal Lagrangian diffeomorphisms to the totally geodesic surface in M. We prove the uniqueness of smooth minimizing maps from (S,h) to M in a given homotopy class. When (S,h) is fixed, smooth minimizing maps from (S,h) are described by a simple holomorphic data on S: a complex self-adjoint Codazzi tensor of determinant 1. The space of admissible data is smooth and naturally equipped with a complex structure, for which the monodromy map taking a data to the holonomy representation of the image is holomorphic. Minimizing maps are in this way reminiscent of shear-bend coordinates, with the complexification of F analoguous to the complex length. [less ▲] Detailed reference viewed: 22 (0 UL)ROBUST BAYES-LIKE ESTIMATION: RHO-BAYES ESTIMATION Baraud, Yannick ; E-print/Working paper (2019) Detailed reference viewed: 31 (7 UL)Trigonometry for the multiples of 3 degrees Perucca, Antonella ; Stranen, Deborah E-print/Working paper (2019) Detailed reference viewed: 34 (4 UL)A hyper-reduction method using adaptivity to cut the assembly costs of reduced order models Hale, Jack ; ; Baroli, Davide et al E-print/Working paper (2019) At every iteration or timestep of the online phase of some reduced-order modelling schemes, large linear systems must be assembled and then projected onto a reduced order basis of small dimension. The ... [more ▼] At every iteration or timestep of the online phase of some reduced-order modelling schemes, large linear systems must be assembled and then projected onto a reduced order basis of small dimension. The projected small linear systems are cheap to solve, but assembly and projection are now the dominant computational cost. In this paper we introduce a new hyper-reduction strategy called reduced assembly (RA) that drastically cuts these costs. RA consists of a triangulation adaptation algorithm that uses a local error indicator to con- struct a reduced assembly triangulation specially suited to the reduced order basis. Crucially, this reduced assembly triangulation has fewer cells than the original one, resulting in lower assembly and projection costs. We demonstrate the efficacy of RA on a Galerkin-POD type reduced order model (RAPOD). We show performance increases of up to five times over the baseline Galerkin-POD method on a non-linear reaction-diffusion problem solved with a semi-implicit time-stepping scheme and up to seven times for a 3D hyperelasticity problem solved with a continuation Newton-Raphson algorithm. The examples are implemented in the DOLFIN finite element solver using PETSc and SLEPc for linear algebra. Full code and data files to produce the results in this paper are provided as supplementary material. [less ▲] Detailed reference viewed: 164 (27 UL)Unramifiedness of weight one Hilbert Hecke algebras ; ; Wiese, Gabor E-print/Working paper (2019) We prove that the Galois pseudo-representation valued in the mod p^n parallel weight 1 Hecke algebra for GL(2) over a totally real number field F is unramified at a place above p if p-1 does not divide ... [more ▼] We prove that the Galois pseudo-representation valued in the mod p^n parallel weight 1 Hecke algebra for GL(2) over a totally real number field F is unramified at a place above p if p-1 does not divide the ramification index at that place. A novel geometric ingredient is the construction and study, in the case when p ramifies in F, of generalised Theta-operators using Reduzzi-Xiao's generalised Hasse invariants, including especially an injectivity criterion in terms of minimal weights. [less ▲] Detailed reference viewed: 18 (3 UL)Practical bounds on the error of Bayesian posterior approximations: A nonasymptotic approach ; Kasprzak, Mikolaj ; et al E-print/Working paper (2019) Detailed reference viewed: 29 (3 UL)Predicting Functional Effects of Missense Variants in Voltage-Gated Sodium and Calcium Channels ; ; et al E-print/Working paper (2019) Malfunctions of voltage-gated sodium and calcium channels (SCN and CACNA1 genes) have been associated with severe neurologic, psychiatric, cardiac and other diseases. Altered channel activity is ... [more ▼] Malfunctions of voltage-gated sodium and calcium channels (SCN and CACNA1 genes) have been associated with severe neurologic, psychiatric, cardiac and other diseases. Altered channel activity is frequently grouped into gain or loss of ion channel function (GOF or LOF, respectively) which is not only corresponding to clinical disease manifestations, but also to differences in drug response. Experimental studies of channel function are therefore important, but laborious and usually focus only on a few variants at a time. Based on known gene-disease-mechanisms, we here infer LOF (518 variants) and GOF (309 variants) of likely pathogenic variants from disease phenotypes of variant carriers. We show regional clustering of inferred GOF and LOF variants, respectively, across the alignment of the entire gene family, suggesting shared pathomechanisms in the SCN/CACNA1 genes. By training a machine learning model on sequence- and structure-based features we predict LOF- or GOF- associated disease phenotypes (ROC = 0.85) of likely pathogenic missense variants. We then successfully validate the GOF versus LOF prediction on 87 functionally tested variants in SCN1/2/8A and CACNA1I (ROC = 0.73) and in exome-wide data from > 100.000 cases and controls. Ultimately, functional prediction of missense variants in clinically relevant genes will facilitate precision medicine in clinical practice. [less ▲] Detailed reference viewed: 71 (0 UL)Consumption home bias and ethnocentrism: an international duopoly Zanaj, Skerdilajda E-print/Working paper (2019) We define a model with two countries and two vertically differentiated goods, a high and a low-quality variant, and heterogenous consumers with respect to their willingness to pay for quality. Consumers ... [more ▼] We define a model with two countries and two vertically differentiated goods, a high and a low-quality variant, and heterogenous consumers with respect to their willingness to pay for quality. Consumers in one country are ethnocentric in consumption. They thrive additional satisfaction when consuming a domestic good rather than a foreign one since only the former can satisfy their sense of place. We investigate the role of trade costs and ethnocentric attitude in shaping the equilibrium configuration of the international duopoly. [less ▲] Detailed reference viewed: 29 (0 UL)Extensional Higher-Order Paramodulation in Leo-III Steen, Alexander ; Benzmüller, Christoph E-print/Working paper (2019) Detailed reference viewed: 20 (0 UL)Trade and Vertical Differentiation Picard, Pierre M ; E-print/Working paper (2019) This paper discusses a trade model with many countries, many goods produced in multiple quality versions, and non-homothetic preferences. It embeds in the same model a series of results that have been ... [more ▼] This paper discusses a trade model with many countries, many goods produced in multiple quality versions, and non-homothetic preferences. It embeds in the same model a series of results that have been empirically confirmed: high-income countries specialize in the production of high-quality goods and trade more of those. Richer countries purchase more high-quality varieties. They import more high-quality products from the most productive exporters. The paper then studies the impact of productivity and population changes on the quality composition of exports. It finally explains why countries import higher quality goods from more distant countries. [less ▲] Detailed reference viewed: 51 (3 UL)Green Urban Areas Picard, Pierre M ; Tran, Thi Thu Huyen E-print/Working paper (2019) This paper studies the size and location of urban green areas across city spaces. Urban green areas offer amenities that affect residential choices, land consumption and land rent. This paper discusses ... [more ▼] This paper studies the size and location of urban green areas across city spaces. Urban green areas offer amenities that affect residential choices, land consumption and land rent. This paper discusses the socially optimal sizes and locations of urban green areas within a city and their decentralized allocation through land markets. The main result is that the share of land dedicated to urban green areas is a concave function of the distance to the city center. This result is confirmed by the empirical study of urban structures in the 305 largest EU cities. The importance of urban green areas is finally assessed by a counterfactual analysis, where 50% of urban green areas are removed in each city. [less ▲] Detailed reference viewed: 61 (8 UL)Social division in the market: conspicous consumption with nationalist feelings Zanaj, Skerdilajda E-print/Working paper (2019) In this paper, we explore the effects of conspicuous goods as a means of social division between native citizens and migrants. We push forward the hypothesis that choosing a particular good can confer a ... [more ▼] In this paper, we explore the effects of conspicuous goods as a means of social division between native citizens and migrants. We push forward the hypothesis that choosing a particular good can confer a sense of place. We introduce this idea in an international vertical differentiation market with two variants and two social groups: migrants and natives. Natives are narrow-minded since they attribute a positive social value to the variant that complies with their own consumption culture. Migrants are open-minded. When consumers belonging to different groups meet, they exchange information about their consumption habits and consumption well-being that reveals their consumption culture: narrow-minded versus open-minded. Consequently, after meeting, some consumers may change beliefs (narrow-minded to open-minded or vice versa) and consumption choices. Using a dynamic model, we fully elucidate the steady-state equilibrium and highlight the impact of nationalism on migrant integration. [less ▲] Detailed reference viewed: 30 (0 UL)Implied Volatility Sentiment: A Tale of Two Tails Kräussl, Roman ; ; E-print/Working paper (2019) Detailed reference viewed: 17 (0 UL)Kummer theory for number fields and the reductions of algebraic numbers Perucca, Antonella ; Sgobba, Pietro E-print/Working paper (2019) For all number fields the failure of maximality for the Kummer extensions is bounded in a very strong sense. We give a direct proof (without relying on the Bashmakov-Ribet method) of the fact that if G is ... [more ▼] For all number fields the failure of maximality for the Kummer extensions is bounded in a very strong sense. We give a direct proof (without relying on the Bashmakov-Ribet method) of the fact that if G is a finitely generated and torsion-free multiplicative subgroup of a number field K having rank r, then the ratio between n^r and the Kummer degree [K(\zeta_n,\sqrt[n]{G}):K(\zeta_n)] is bounded independently of n. We then apply this result to generalise to higher rank a theorem of Ziegler from 2006 about the multiplicative order of the reductions of algebraic integers (the multiplicative order must be in a given arithmetic progression, and an additional Frobenius condition may be considered). [less ▲] Detailed reference viewed: 130 (29 UL)Dynamical strategies for obstacle avoidance during Dictyostelium discoideum aggregation: a Multi-agent system model Proverbio, Daniele ; E-print/Working paper (2019) Chemotaxis, the movement of an organism in response to a chemical stimulus, is a typical feature of many microbiological systems. In particular, the social amoeba Disctyostelium discoideum is widely used ... [more ▼] Chemotaxis, the movement of an organism in response to a chemical stimulus, is a typical feature of many microbiological systems. In particular, the social amoeba Disctyostelium discoideum is widely used as a model organism, but it is not still clear how it behaves in heterogeneous environments. A few models focused on mechanical features have already addressed the question; however, we propose that phenomenological models focusing on the dynamics may provide new meaningful data. Consequently, by means of a specific Multi-agent system model, we studied the dynamical features emerging from complex social interactions among individuals belonging to amoeboids colonies. After defining an appropriate metric to perform meaningful measurements, we found that: a) obstacles play the role of local topological perturbation, as they alter the flux of chemical signals; b) that obstacle that physically block the cellular motion as well as the chemicals elicit dynamical evolutions that are not statistically distinguishable from the case where obstacles that do not interfere physically with said motion; c) that fluctuations of the dynamics can lead to better exploration of the physical space, thus preventing multiple stable aggregates. From previous results, we may speculate about the fact that chemotactic cells, in many cases, can avoid obstacles by simply following the altered chemical gradient: social interactions seem to be sufficient to guarantee the aggregation of the whole colony past numerous obstacles. It is then unlikely that cells have developed special mechanisms to cope with the presence of topological perturbation sources. Nevertheless, we suggest that further studies can provide better understanding and that, in order to gain deeper knowledge, mechanical models should be coupled with phenomenological, system-oriented ones. [less ▲] Detailed reference viewed: 45 (3 UL)Cluster Analysis for Investment funds portfolio optimisation: A symbolic data approach Terraza, Virginie ; E-print/Working paper (2019) Detailed reference viewed: 50 (1 UL)Bianchi's additional symmetries Rahm, Alexander E-print/Working paper (2019) Detailed reference viewed: 25 (1 UL)Addendum to: Reductions of algebraic integers Perucca, Antonella ; Sgobba, Pietro ; Tronto, Sebastiano E-print/Working paper (2019) Let K be a number field, and let G be a finitely generated and torsion-free subgroup of K*. We consider Kummer extensions of G of the form K(\zeta_{2^m}, \sqrt[2^n]G)/K(\zeta_{2^m}), where n \leq m. In ... [more ▼] Let K be a number field, and let G be a finitely generated and torsion-free subgroup of K*. We consider Kummer extensions of G of the form K(\zeta_{2^m}, \sqrt[2^n]G)/K(\zeta_{2^m}), where n \leq m. In the paper "Reductions of algebraic integers" (J. Number Theory, 2016) by Debry and Perucca, the degrees of those extensions have been evaluated in terms of divisibility parameters over K(\zeta_4). We prove how properties of G over K explicitly determine the divisibility parameters over K(\zeta_4). This result has a clear computational advantage, since no field extension is required. [less ▲] Detailed reference viewed: 95 (17 UL)UC Priced Oblivious Transfer with Purchase Statistics and Dynamic Pricing Damodaran, Aditya Shyam Shankar ; ; Rial Duran, Alfredo E-print/Working paper (2019) Priced oblivious transfer (POT) is a cryptographic protocol that can be used to protect customer privacy in e-commerce applications. Namely, it allows a buyer to purchase an item from a seller without ... [more ▼] Priced oblivious transfer (POT) is a cryptographic protocol that can be used to protect customer privacy in e-commerce applications. Namely, it allows a buyer to purchase an item from a seller without disclosing to the latter which item was purchased and at which price. Unfortunately, existing POT schemes have some drawbacks in terms of design and functionality. First, the design of existing POT schemes is not modular. Typically, a POT scheme extends a k-out-of-N oblivious transfer (OT) scheme by adding prices to the items. However, all POT schemes do not use OT as a blackbox building block with certain security guarantees. Consequently, security of the OT scheme needs to be reanalyzed while proving security of the POT scheme, and it is not possible to swap the underlying OT scheme with any other OT scheme. Second, existing POT schemes do not allow the seller to obtain any kind of statistics about the buyer's purchases, which hinders customer and sales management. Moreover, the seller is not able to change the prices of items without restarting the protocol from scratch. We propose a POT scheme that addresses the aforementioned drawbacks. We prove the security of our POT in the UC framework. We modify a standard POT functionality to allow the seller to receive aggregate statistics about the buyer's purchases and to change prices dynamically. We present a modular construction for POT that realizes our functionality in the hybrid model. One of the building blocks is an ideal functionality for OT. Therefore, our protocol separates the tasks carried out by the underlying OT scheme from the additional tasks needed by a POT scheme. Thanks to that, our protocol is a good example of modular design and can be instantiated with any secure OT scheme as well as other building blocks without reanalyzing security from scratch. [less ▲] Detailed reference viewed: 62 (17 UL)Exponential integrability and exit times of diffusions on sub-Riemannian and RCD*(K,N) spaces Thompson, James ; Thalmaier, Anton E-print/Working paper (2019) In this article we derive moment estimates, exponential integrability, concentration inequalities and exit times estimates for canonical diffusions in two settings each beyond the scope of Riemannian ... [more ▼] In this article we derive moment estimates, exponential integrability, concentration inequalities and exit times estimates for canonical diffusions in two settings each beyond the scope of Riemannian geometry. Firstly, we consider sub-Riemannian limits of Riemannian foliations. Secondly, we consider the non-smooth setting of RCD*(K,N) spaces. In each case the necessary ingredients are an Ito formula and a comparison theorem for the Laplacian, for which we refer to the recent literature. As an application, we derive pointwise Carmona-type estimates on eigenfunctions of Schrodinger operators. [less ▲] Detailed reference viewed: 103 (22 UL)Grenzüberschreitende Zusammenarbeit als Praxisformation. Perspektiven für eine alternative Kooperationsforschung Wille, Christian ; Connor, Ulla E-print/Working paper (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: 46 (6 UL)Worin liegen die Chancen und Risiken der verstärkten Nutzung von Informations- und Kommunikationstechnologien außerhalb des Arbeitsplatzes? Sischka, Philipp ; Steffgen, Georges E-print/Working paper (2018) Rund 11% der Arbeitnehmer in Luxemburg können der Gruppe zugeordnet werden, die häufig Informations- und Kommunikationstechnologien nutzt, um fern von ihrer organisationalen Arbeitsstelle zu arbeiten ... [more ▼] Rund 11% der Arbeitnehmer in Luxemburg können der Gruppe zugeordnet werden, die häufig Informations- und Kommunikationstechnologien nutzt, um fern von ihrer organisationalen Arbeitsstelle zu arbeiten. Insbesondere bei männlichen und höher gebildeten Arbeitnehmern sowie bei Managern und Arbeitnehmern in akademischen Berufen ist dieser Anteil an Nutzern stärker ausgeprägt. Diese Arbeitsplatz fernen Nutzer von Informationstechnologien geben im Durchschnitt ein höheres Maß an Autonomie und Partizipation bei der Arbeit an, sind jedoch verstärkt von problematischen psychosozialen Arbeitsbedingungen (z.B. Mobbing, Work-Life-Konflikte) sowie Burnout betroffen. [less ▲] Detailed reference viewed: 36 (2 UL)Bowditch's Q-conditions and Minsky's primitive stability ; Xu, Binbin E-print/Working paper (2018) For the action of the outer automorphism group of the rank two free group on the corresponding variety of PSL(2,C) characters, two domains of discontinuity have been known to exist that are strictly ... [more ▼] For the action of the outer automorphism group of the rank two free group on the corresponding variety of PSL(2,C) characters, two domains of discontinuity have been known to exist that are strictly larger than the set of Schottky characters. One is introduced by Bowditch in 1998 (followed by Tan, Wong and Zhang in 2008) and the other by Minsky in 2013. We prove that these two domains are equal. We then show that they are contained in the set of characters having what we call the bounded intersection property. [less ▲] Detailed reference viewed: 55 (5 UL)On Degree-d Zero-Sum Sets of Full Rank Beierle, Christof ; Biryukov, Alex ; Udovenko, Aleksei E-print/Working paper (2018) A set S⊆Fn2 is called degree-d zero-sum if the sum ∑s∈Sf(s) vanishes for all n-bit Boolean functions of algebraic degree at most d. Those sets correspond to the supports of the n-bit Boolean functions of ... [more ▼] A set S⊆Fn2 is called degree-d zero-sum if the sum ∑s∈Sf(s) vanishes for all n-bit Boolean functions of algebraic degree at most d. Those sets correspond to the supports of the n-bit Boolean functions of degree at most n−d−1. We prove some results on the existence of degree-d zero-sum sets of full rank, i.e., those that contain n linearly independent elements, and show relations to degree-1 annihilator spaces of Boolean functions and semi-orthogonal matrices. We are particularly interested in the smallest of such sets and prove bounds on the minimum number of elements in a degree-d zero-sum set of rank n. The motivation for studying those objects comes from the fact that degree-d zero-sum sets of full rank can be used to build linear mappings that preserve special kinds of nonlinear invariants, similar to those obtained from orthogonal matrices and exploited by Todo, Leander and Sasaki for breaking the block ciphers Midori, Scream and iScream. [less ▲] Detailed reference viewed: 27 (1 UL)THE PILATUS BANK SCANDAL: TIME TO RECONSIDER BANKING SUPERVISION, ANTI-MONEY LAUNDERING AND WHISTLE-BLOWER’S PROTECTION IN THE EU Kafteranis, Dimitrios E-print/Working paper (2018) Detailed reference viewed: 36 (1 UL) |
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