Virtual network embedding in the cycle

AbstractWe consider a problem motivated by the design of Asynchronous transfer mode (ATM) networks. Given a physical network and an all-to-all traffic, the problem consists in designing a virtual network with a given diameter, which can be embedded in the physical one with a minimum congestion (the congestion is the maximum load of a physical link). Here we solve the problem when the physical network is a ring. We give an almost optimal solution for diameter 2 and bounds for large diameters

Caractéristiques de l’évaluation des apprentissages dans une faculté de génie

Bien que l’évaluation des apprentissages soit omniprésente dans le contexte universitaire, ses caractéristiques sont mal connues. Cette recherche décrit en détail les caractéristiques de l’évaluation des apprentissages, précisément dans une faculté de génie située au Québec, en réalisant un inventaire des pratiques déclarées des professeurs et des chargés de cours et en analysant les caractéristiques de leur démarche d’évaluation. Cette recherche s’appuie sur un devis mixte et une approche pragmatique afin de combiner une approche plus large et une approche plus précise. Dans un premier temps, 42 enseignants d’une faculté de génie située au Québec ont rempli un questionnaire de 171 items touchant à tous les aspects de l’évaluation des apprentissages. Dans un deuxième temps, 9 de ces enseignants ont participé à une entrevue individuelle d’une heure portant sur l’évaluation des apprentissages dans une activité pédagogique dont ils ont la responsabilité. Trois axes ont été utilisés afin d’analyser les données ainsi recueillies : le paradigme sous-tendant les programmes, une proposition de démarche d’évaluation des apprentissages et le concept de validation. Les trois paradigmes retenus sont le paradigme traditionnel, le paradigme centré sur l’apprenant et l’approche par compétences. La démarche d’évaluation des apprentissages spécifiquement définie pour cette recherche comporte 8 grandes étapes parmi lesquelles certaines sont séparées en sous-étapes : (1) l’identification des cibles d’apprentissage et des fonctions de l’évaluation des apprentissages, (2) la planification de l’évaluation, (3) la collecte de données, (4) l’interprétation, (5) le jugement de la justesse et de la pertinence des données, (6) la prise de décisions, (7) la communication des décisions et (8) l’amélioration continue. Pour chacune de ces étapes, nous avons décrit les pratiques cohérentes au moyen des 3 paradigmes puis, en retenant le concept de chaine associé à celui de validation, nous avons analysé les données dans l’intention de déterminer la force de chacune des étapes de la démarche. Suite à l’analyse des résultats, certains constats sont apparus. D’abord, les modalités d’évaluation associées au paradigme traditionnel sont très importantes pour les répondants, et ce, même dans les programmes s’affichant par compétences. Cela signifie que l’utilisation de tâches moins complexes, comme des examens finaux écrits, est considérable. Toutefois, certains répondants délaissent ces modalités au profit d’autres permettant de suivre la progression des étudiants. C’est le cas des projets longs de conception. Ensuite, il appert que de toutes les étapes de la démarche d’évaluation, les répondants n’en réalisent que quelques-unes : la planification, la collecte de données, l’interprétation et l’attribution des notes au relevé de notes. En effet, les étapes de jugement de la justesse et de la pertinence des données et de prise de décisions semblent négligées par les répondants. Finalement, il ressort manifestement de cette recherche que les répondants n’ont pas de moyens spécifiques pour déterminer la qualité des inférences sur les capacités des étudiants. Et sans ces moyens, il devient difficile de déterminer la qualité de ces inférences. La présente recherche comble un vide sur les pratiques concrètes des professeurs et des chargés de cours lors de l’évaluation des apprentissages. Selon notre recension, plusieurs innovations sont proposées, mais il existe une méconnaissance sur la façon dont les enseignants réalisent l’évaluation. Cette recherche apporte certains éléments de réponses, des questionnements et une proposition de démarche évaluative permettant d’analyser les pratiques existantes

Crypto'Graph: Leveraging Privacy-Preserving Distributed Link Prediction for Robust Graph Learning

Graphs are a widely used data structure for collecting and analyzing relational data. However, when the graph structure is distributed across several parties, its analysis is particularly challenging. In particular, due to the sensitivity of the data each party might want to keep their partial knowledge of the graph private, while still willing to collaborate with the other parties for tasks of mutual benefit, such as data curation or the removal of poisoned data. To address this challenge, we propose Crypto'Graph, an efficient protocol for privacy-preserving link prediction on distributed graphs. More precisely, it allows parties partially sharing a graph with distributed links to infer the likelihood of formation of new links in the future. Through the use of cryptographic primitives, Crypto'Graph is able to compute the likelihood of these new links on the joint network without revealing the structure of the private individual graph of each party, even though they know the number of nodes they have, since they share the same graph but not the same links. Crypto'Graph improves on previous works by enabling the computation of a certain number of similarity metrics without any additional cost. The use of Crypto'Graph is illustrated for defense against graph poisoning attacks, in which it is possible to identify potential adversarial links without compromising the privacy of the graphs of individual parties. The effectiveness of Crypto'Graph in mitigating graph poisoning attacks and achieving high prediction accuracy on a graph neural network node classification task is demonstrated through extensive experimentation on a real-world dataset

Fast and inexpensive method for the fabrication of transparent pressure-resistant microfluidic chips

The recent rise of high-pressure applications in microfluidics has led to the development of different types of pressure-resistant microfluidic chips. For the most part, however, the fabrication methods require clean room facilities, as well as specific equipment and expertise. Furthermore, the resulting microfluidic chips are not always well suited to flow visualization and optical measurements. Herein, we present a method that allows rapid and inexpensive prototyping of optically transparent microfluidic chips that resist pressures of at least 200 bar. The fabrication method is based on UV-curable off-stoichiometry thiol-ene epoxy (OSTE+) polymer, which is chemically bonded to glass. The reliability of the device was verified by pressure tests using CO2, showing resistance without failure up to at least 200 bar at ambient temperature. The microchips also resisted operation at high pressure for several hours at a temperature of 40 °C. These results show that the polymer structure and the chemical bond with the glass are not affected by high-pressure CO2. Opportunities for flow visualization are illustrated by high-pressure two-phase flow shadowgraphy experiments. These microfluidic chips are of specific interest for use with supercritical CO2 and for optical characterization of phase transitions and multiphase flow under near-critical and critical CO2 conditions

Time-budget and location of activities in the paddock can be estimated from GPS-data

Time-budget and location of activities in the paddock can be estimated from GPS-data. 10. International Symposium on the Nutrition of Herbivores (ISNH

Conservation Status and Abundance of the Crowned Sifaka (Propithecus coronatus)

The crowned sifaka (Propithecus coronatus) is Endangered. It has a large but highly fragmented distribution; its known range extends from the Betsiboka River in the north of Madagascar, to the Mahavavy River in the north-west, and down to the Tsiribihina River in the south-west. The species lives in forest habitats that are highly and increasingly fragmented and are continuously suffering perturbations and destruction. In order to carry out effective conservation measures targeting P. coronatus, its conservation status needs to be updated so that measures can be taken before anthropogenic or natural environmental changes lead to the extirpation of the species in most of its forests. We (i) identified forest fragments where the species is still present and (ii) using the line-transect “Distance” sampling method, estimated the population size and density in the principal remaining forest fragments in the northern part of its range, including both protected and unprotected areas. We visited most of the forests in the northern part of its range in order to update the current area of occupancy, and to rate the state of its forests using a qualitative “forest quality index.” Our survey results have shown that (i) a large number of forests have disappeared or decreased in size in the last 10 years, and (ii) population densities vary considerably among forest fragments (ranging from 49 to 309 individuals per km²), with some very high densities in forests located along the Mahavavy River and in the Antrema area. Their abundance in the area surveyed is likely to be between 4,226 and 36,672 individuals, and most probably above 10,000. It is difficult to extrapolate from these estimates to the total abundance across the species’ entire range, but we estimate that it is likely to be large, probably between 130,000 and 220,000 individuals. Unfortunately, many field observations suggest that its populations continue to decline at a high rate due to habitat loss and hunting, and we argue for the re-evaluation of the conservation status from Endangered A2cd to Endangered A4acd, and the need to survey the rest of the range of P.coronatus.FCT grant: (SFRH/BD/64875/2009), Institut Français de la Biodiversité, Programme Biodiversité de l’Océan Indien (ref.CD-AOOI-07-003), the GDRI Madagascar, the "Laboratoire d’Excellence" (LABEX) entitled TULIP: (ANR -10-LABX-41), Instituto Gulbenkian de Ciência, “Optimus Alive!” Biodiversity grant, University of Mahajanga, Département de Biologie Animale et Ecologie, Fanamby NGO

Deformed strings in the Heisenberg model

We investigate solutions to the Bethe equations for the isotropic S = 1/2 Heisenberg chain involving complex, string-like rapidity configurations of arbitrary length. Going beyond the traditional string hypothesis of undeformed strings, we describe a general procedure to construct eigenstates including strings with generic deformations, discuss general features of these solutions, and provide a number of explicit examples including complete solutions for all wavefunctions of short chains. We finally investigate some singular cases and show from simple symmetry arguments that their contribution to zero-temperature correlation functions vanishes.Comment: 34 pages, 13 figure

Le sanctuaire gallo-romain de Vieille-Cour à Mauves-sur-Loire (Loire-Atlantique): bilan des connaissances

Le sanctuaire de l’agglomération antique de Mauves-sur-Loire (Loire-Atlantique) a été fouillé en 1885-1886, 1966 et 1976-1979, mais est resté pratiquement inédit. La reprise de l’ensemble de la documentation de fouille permet d’en proposer une lecture renouvelée. Après une occupation laténienne d’interprétation malaisée, les phases principales datent du début du iersiècle, du dernier tiers de ce même siècle et du milieu du iie: elles signent le passage d’une aire cultuelle relativement modeste, où aucun temple n’a pu être reconnu, à un temple romano-celtique lui-même transformé ensuite en un édifice périptère sur podium. Le sanctuaire est abandonné dans le courant de la seconde moitié du ivesiècle de notre ère. Les mobiliers associés font l’objet d’une étude plus ou moins complète suivant les cas, à vocation chronologique ou thématique.The sanctuary of the Gallo-Roman small town of Mauves-sur-Loire (Loire-Atlantique) was excavated in 1885-1886, 1966 and 1976-1979, but has so far remained practically unpublished. Going back over the whole documentation related to the excavation now provides an opportunity to cast a new light on these documents. After a La Tene occupation which is not easy to interpret, the three main phases date from the the early 1st century AD, the last third of the same century, and the middle 2nd one : they signal the passage from a relatively small worship area, where no temple could be recognized, to a Romano-Celtic temple, which itself was then transformed into a pillared bulding on podium. The sanctuary was abandoned during the second half of 4th century. Associated assemblages are the subject of a study which, depending on the topics, is more or less comprehensive, and which is conducted from a chronological or thematic standpoint

Multiple Promoters and Alternative Splicing: Hoxa5 Transcriptional Complexity in the Mouse Embryo

The genomic organization of Hox clusters is fundamental for the precise spatio-temporal regulation and the function of each Hox gene, and hence for correct embryo patterning. Multiple overlapping transcriptional units exist at the Hoxa5 locus reflecting the complexity of Hox clustering: a major form of 1.8 kb corresponding to the two characterized exons of the gene and polyadenylated RNA species of 5.0, 9.5 and 11.0 kb. This transcriptional intricacy raises the question of the involvement of the larger transcripts in Hox function and regulation.We have undertaken the molecular characterization of the Hoxa5 larger transcripts. They initiate from two highly conserved distal promoters, one corresponding to the putative Hoxa6 promoter, and a second located nearby Hoxa7. Alternative splicing is also involved in the generation of the different transcripts. No functional polyadenylation sequence was found at the Hoxa6 locus and all larger transcripts use the polyadenylation site of the Hoxa5 gene. Some larger transcripts are potential Hoxa6/Hoxa5 bicistronic units. However, even though all transcripts could produce the genuine 270 a.a. HOXA5 protein, only the 1.8 kb form is translated into the protein, indicative of its essential role in Hoxa5 gene function. The Hoxa6 mutation disrupts the larger transcripts without major phenotypic impact on axial specification in their expression domain. However, Hoxa5-like skeletal anomalies are observed in Hoxa6 mutants and these defects can be explained by the loss of expression of the 1.8 kb transcript. Our data raise the possibility that the larger transcripts may be involved in Hoxa5 gene regulation.Our observation that the Hoxa5 larger transcripts possess a developmentally-regulated expression combined to the increasing sum of data on the role of long noncoding RNAs in transcriptional regulation suggest that the Hoxa5 larger transcripts may participate in the control of Hox gene expression

Transition numérique et pratiques de recherche et d’enseignement supérieur en agronomie, environnement, alimentation et sciences vétérinaires à l’horizon 2040.

Pour citer ce document:Barzman M. (Coord.), Gerphagnon M. (Coord.), Mora O. (Coord.),Aubin-Houzelstein G., Bénard A., Martin C., Baron G.L, Bouchet F., Dibie-Barthélémy J., Gibrat J.F., Hodson S., Lhoste E., Moulier-Boutang Y., Perrot S., Phung F., Pichot C., Siné M., Venin T. 2019. Transition numérique et pratiques de recherche et d’enseignement supérieur en agronomie, environnement, alimentation et sciences vétérinaires à l’horizon 2040.INRA, France, 161pagesTransition numérique et pratiques de recherche et d’enseignement supérieur en agronomie, environnement, alimentation et sciences vétérinaires à l’horizon 2040