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See detailA Quantitative Doignon-Bell-Scarf theorem
Aliev, Iskander; Bassett, Robert; De Loera, Jesus et al

in Combinatorica (in press)

The famous Doignon-Bell-Scarf theorem is a Helly-type result about the existence of integer solutions to systems of linear inequalities. The purpose of this paper is to present the following quantitative ... [more ▼]

The famous Doignon-Bell-Scarf theorem is a Helly-type result about the existence of integer solutions to systems of linear inequalities. The purpose of this paper is to present the following quantitative generalization: Given an integer k, we prove that there exists a constant c(n,k), depending only on the dimension n and on the number k, such that if a bounded polyhedron {x in R^n : Ax <= b} contains exactly k integer points, then there exists a subset of the rows, of cardinality no more than c(n,k), defining a polyhedron that contains exactly the same k integer points. In this case c(n,0)=2^n as in the original case of Doignon-Bell-Scarf for infeasible systems of inequalities. We work on both upper and lower bounds for the constant c(n,k) and discuss some consequences, including a Clarkson-style algorithm to find the l-th best solution of an integer program with respect to the ordering induced by the objective function. [less ▲]

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See detailParametric Polyhedra with at least k Lattice Points: Their Semigroup Structure and the k-Frobenius Problem
Aliev, Iskander; De Loera, Jesus; Louveaux, Quentin ULg

in Beveridge, Andrew; Griggs, Jerold; Hogben, Leslie (Eds.) et al Recent trends in Combinatorics (in press)

The well-studied semigroup Sg(A) = {b : b = Ax; x in Z^n; x >= 0} can be stratified by the sizes of the polyhedral fibers IPA(b) = {x : Ax = b; x >= 0; x in Z^n}. The key theme of this paper is a ... [more ▼]

The well-studied semigroup Sg(A) = {b : b = Ax; x in Z^n; x >= 0} can be stratified by the sizes of the polyhedral fibers IPA(b) = {x : Ax = b; x >= 0; x in Z^n}. The key theme of this paper is a structure theory that characterizes precisely the set Sg_k(A) of all vectors b in Sg(A) such that their fiber IPA(b) has at least k-solutions. We demonstrate that this set is finitely generated, a union of translated copies of a semigroup which can be computed explicitly via Hilbert bases computations. Related results can be derived for those right-hand-side vectors b for which IPA(b) has exactly k solutions or fewer than k solutions. We also show that, when n, k are fixed natural numbers, one can compute in polynomial time an encoding of Sg_k(A) as a generating function, using a short sum of rational functions. As a consequence, one can identify all right-hand-side vectors that have at least k solutions. Using this tool we prove that for fixed n; k the k-Frobenius number can be computed in polynomial time, generalizing a well-known result of R. Kannan. [less ▲]

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See detailFLOR-ID: an interactive database of flowering-time gene networks in Arabidopsis thaliana
Bouché, Frédéric ULg; Lobet, Guillaume ULg; Tocquin, Pierre ULg et al

in Nucleic Acids Research (in press)

Flowering is a hot topic in Plant Biology and important progress has been made in Arabidopsis thaliana toward unravelling the genetic networks involved. The increasing complexity and the explosion of ... [more ▼]

Flowering is a hot topic in Plant Biology and important progress has been made in Arabidopsis thaliana toward unravelling the genetic networks involved. The increasing complexity and the explosion of literature however require development of new tools for information management and update. We therefore created an evolutive and interactive database of flowering time genes, named FLOR-ID (Flowering-Interactive Database), that is available freely at http://www.flor-id.org. The hand-curated database contains information on 306 genes and links to 1595 publications gathering the work of more than 4500 authors. Gene function and interactions within the flowering pathways were inferred from the analysis of related publications, included in the database and translated into interactive manually drawn snapshots. [less ▲]

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See detailBiolaw and dual use dilemma: the freedom of scientific research in relationship with traditional and emerging sciences and technologies
Colussi, Ilaria Anna ULg

in International Journal of Biolaw (in press)

Science and technology require an intervention by the law, and law is called upon to intervene in front of their evolution, and to look for proper solutions of governance and rational responses to their ... [more ▼]

Science and technology require an intervention by the law, and law is called upon to intervene in front of their evolution, and to look for proper solutions of governance and rational responses to their risks. One of the main issues to be investigated from the legal viewpoint is represented by the ‘dual-use dilemma’ that arises both in ‘traditional’ and new areas of techno-sciences. Indeed, any kind of research has the potential to be used both for bad as well as for good purposes. Therefore, it is important to reflect upon the ways to control possibly dangerous research without preventing the progress from going further. Such ‘dual-use dilemma’, then, entails the study of one of the fundamental freedoms in the biolaw area: the freedom of scientific research, its limits, and relationship with other rights/needs/freedoms (such the need of security). This work focuses on two areas of the techno-scientific world. One is more ‘traditional’, i.e. nuclear science, in whose context the reflections on ‘dual-use’ were born and developed, and the other one is a new emerging technology, which is synthetic biology. The aim is to understand how the freedom of scientific research could be shaped in relationship with other rights/needs/interests for dealing with ‘dual-use’ issues in the aforementioned areas of science and technology. [less ▲]

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See detailCarte géologique Huy-Nandrin (48/3-4): notice explicative
Mottequin, Bernard ULg; Marion, Jean-Marc ULg

Book published by Université de Liège (in press)

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See detailCarte géologique de Wallonie (Belgique) 1/10.000. 59/3 Rochefort
Barchy, Laurent; Dejonghe, Léon; Marion, Jean-Marc ULg

Cartographic material (in press)

New geological map of Wallonia published at the scale of 1/25.000, based on a new field work and using previous scientific data, produced since the previous edition published in 1900 (Stainier)

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See detailEfficient ANOVA for directional data
Swan, Yvik ULg; Ley, Christophe; Verdebout, Thomas

in Annals of the Institute of Statistical Mathematics (in press)

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See detailParametric Stein operators and variance bounds
Swan, Yvik ULg; Ley, Christophe

in Brazilian Journal of Probability and Statistics (in press)

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See detailGROMPALA: a membrane-implicit modelling method to screen lipid-interacting molecules
Steinhauer, Sven; Crowet, Jean-Marc ULg; Brasseur, Robert ULg et al

in Software and techniques for Bio-molecular modeling (in press)

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See detailConstraints on the structure of 16 Cygni A and 16 Cygni B using inversion techniques
Buldgen, Gaël ULg; Reese, Daniel; Dupret, Marc-Antoine ULg

in Astronomy and Astrophysics (in press)

Abstract Constraining mixing processes and chemical composition is a central problem in stellar physics as their impact on stellar age determinations leads to biases in our studies of stellar evolution ... [more ▼]

Abstract Constraining mixing processes and chemical composition is a central problem in stellar physics as their impact on stellar age determinations leads to biases in our studies of stellar evolution, galactic history and exoplanetary systems. In two previous papers, we showed how seismic inversion techniques could offer strong constraints on such processes by pointing out weaknesses in theoretical models. We now apply our technique to the solar analogues 16CygA and 16CygB, being amongst the best targets in the Kepler field to test the diagnostic potential of seismic inversions. The combination of various seismic indicators helps to provide more constrained and accurate fundamendal parameters for these stars. We use the latest seismic, spectroscopic and interferometric observational constraints in the litterature for this system to determine reference models independently for both stars. We carry out seismic inversions of the acoustic radius, the mean density and a core conditions indicator. We note that a degeneracy exists for the reference models. Namely, changing the diffusion coefficient or the chemical composition within the observational values leads to 5% changes in mass, 3% changes in radius and up to 8% changes in age. We use acoustic radius and mean density inversions to improve our reference models then carry out inversions for a core conditions indicator. Thanks to its sensitivity to microscopic diffusion and chemical composition mismatches, we are able to reduce the mass dispersion to 2%, namely [0.96, 1.0] M_sun, the radius dispersion to 1%, namely [1.188, 1.200] R_sun and the age dispersion to 3%, namely [7.0, 7.4] Gy, for 16CygA. For 16CygB, we can check the consistency of the models but not reduce independently the age dispersion. Nonetheless, assuming consistency with the age of 16CygA helps to further constrain its mass and radius. [less ▲]

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See detailCT SCAN FEATURES OF PRESUMPTIVE HAEMORRHAGIC STROKE IN A DOG WITH CUSHING’S DISEASE
Liotta, Annalisa Pia ULg; Cavrenne, Romain; Peeters, Dominique ULg et al

in Case reports in Veterinary Medicine (in press)

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See detailFernand De Visscher et la Société Internationale d'Histoire des Droits de l'Antiquité
Gerkens, Jean-François ULg

in Revue Historique de Droit Français et Etranger (in press)

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See detailVirtual reality as a complementary therapy to sexual addiction treatment
Cismaru Inescu, Adina; Andrianne, Robert ULg; Triffaux, Jean-Marc ULg

in International Journal of Advanced Computer Science (in press), 3(7), 1-5

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See detailDe l'état littéraire à une théorie de l'Etat. Une lecture cursive de La Musique et les Lettres
Durand, Pascal ULg

in Millan, Gordon (Ed.) Mallarmé à Tournon et au-delà (in press)

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See detailNécrologie d'Emmanuel Closset
George, Philippe ULg

in Bulletin de l'Institut Archéologique Liégeois (in press)

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See detailNewt life after fish introduction: extirpation of paedomorphosis in a mountain fish lake and newt use of satellite pools
Denoël, Mathieu ULg; Scime, Patrick; Zambelli, Nicola

in Current Zoology (in press), 62

Fish introduction is one of the main causes of amphibian decline worldwide. It affects particularly rare aquatic phenotypes such as paedomorphs, which retain gills during the adult stage. In this context ... [more ▼]

Fish introduction is one of the main causes of amphibian decline worldwide. It affects particularly rare aquatic phenotypes such as paedomorphs, which retain gills during the adult stage. In this context, we determined whether small wetlands, such as pools surrounding fished and fishless lakes, could sustain paedomorphic and metamorphic newts. To this end, we surveyed lakes known historically to sustain Alpine newts (Ichthyosaura alpestris) as well as 35 nearby pools. On the basis of the published records, the only known population exhibiting paedomorphosis in the Swiss Alps was found to be extirpated by salmonid introductions. However, the metamorphs persisted in peripheral pools, paedomorphosis was discovered at a new locality, and overwintering larvae were still present in one of the lakes. These results show the importance of conserving varied aquatic habitats such as pools in mountainous environments where the main resources can become unsuitable for amphibians because of fish introductions. Pools may also function as reservoirs in maintaining newt populations until programs to remove fish from lakes can be carried out. It is not known if paedomorphs could reappear after fish removal. However, the combined resilience of amphibians after fish removal and the genetic basis for paedomorphosis highlighted in other taxa by previous studies suggest that there is the potential to maintain this intraspecific case of diversity even after its disappearance. [less ▲]

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See detailFrequency, characteristics, and perceived functions of emotional future thinking in daily life
Barsics, Catherine ULg; Van der Linden, Martial ULg; D'Argembeau, Arnaud ULg

in Quarterly Journal of Experimental Psychology [=QJEP] (in press)

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See detailOpen Access and Discovery Tools: How do Primo Libraries Manage Green Open Access Collections?
Renaville, François ULg

in Varnum, Ken (Ed.) Exploring Discovery: The Front Door to Your Library's Licensed and Digitized Content (in press)

Scholarly Open Access repositories contain lots of treasures including rare or otherwise unpublished materials and articles that scholars self-archive, often as part of their institution's mandate. But it ... [more ▼]

Scholarly Open Access repositories contain lots of treasures including rare or otherwise unpublished materials and articles that scholars self-archive, often as part of their institution's mandate. But it can be hard to discover this material unless users know exactly where to look. Since the very beginning, libraries have played a major role in supporting the OA movement. Next to all services they can provide to support the deposit of research output in the repositories, they can make Open Access materials widely discoverable by their patrons through general search engines (Google, Bing...), specialized search engines (like Google Scholar) and library discovery tools, thus expanding their collection to include materials that they would not necessarily pay for. In this paper, we intend to focus on two aspects regarding Open Access and Primo discovery tool. In early 2013, Ex Libris Group started to add institutional repositories to Primo Central Index (PCI), their mega-aggregation of hundreds of millions of scholarly e-resources. After 2 years, it may be interesting to take stock of the current situation of PCI regarding Open Access institutional repositories. On basis of a survey to carry out among the Primo community, the paper also shows how libraries using Primo discovery tool integrate Green Open Access contents in their catalog. Two major ways are possible for them: Firstly, they can directly harvest, index and manage any repository in their Primo and display those free contents next to the more traditional library collections; Secondly, if they are PCI subscribers, they can quickly and easily activate any, if not all, of the Open Access repositories contained PCI, making thus the contents of those directly discoverable to their end users. [less ▲]

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