A Method to Discover Digital Collaborative Conversations in Business Collaborations

Many companies have a suite of digital tools, such as Enterprise Social Networks, conferencing and document sharing software, and email, to facilitate collaboration among employees. During, or at the end of a collaboration, documents are often produced. People who were not involved in the initial collaboration often have difficulties understanding parts of its content because they are lacking the overall context. We argue there is valuable contextual and collaborative knowledge contained in these tools (content and use) that can be used to understand the document. Our goal is to rebuild the conversations that took place over a messaging service and their links with a digital conferencing tool during document production. The novelty in our approach is to combine several conversation-threading methods to identify interesting links between distinct conversations. Specifically we combine header-field information with social, temporal and semantic proximities. Our findings suggest the messaging service and conferencing tool are used in a complementary way. The primary results confirm that combining different conversation threading approaches is efficient to detect and construct conversation threads from distinct digital conversations concerning the same document

Automatic High-Level Hardware Checkpoint Selection for Reconfigurable Systems

International audience—Modern FPGAs provide great computational power and flexibility but there is still room for improving their performances. For example multiuser approaches are particularly underdeveloped as they require specific mechanisms still to be automated. Sharing an FPGA resource between applications or users requires a context switch ability. The latter enables pausing and resuming applications at system demand. This paper presents a method that automatically selects a good execution point, called hardware checkpoint, to perform a context switch on an FPGA. The method relies on a static analysis of the finite state machine of a circuit to select the checkpoint states. The obtained selection ensures that the context switch mechanism respects a given latency and tries to minimize the mechanism costs. The method takes advantage of its integration in an open-source HLS tool and preliminary results highlight its efficiency. Index Terms—FPGA, HLS, CAD, hardware context switc

Instability strips of main sequence B stars: a parametric study of iron enhancement

The discovery of beta Cephei stars in low metallicity environments, as well as the difficulty to theoretically explain the excitation of the pulsation modes observed in some beta Cephei and SPB stars, suggest that the iron opacity ``bump'' provided by standard models could be underestimated. We investigate, by means of a parametric study, the effect of a local iron enhancement on the location of the beta Cephei and SPB instability strips.Comment: 2 pages, to appear in the proceedings of "Vienna Workshop on the Future of Asteroseismology", September 20-22, 200

Flot de conception automatique pour circuits commutables

National audienceLes FPGA, ou puces reconfigurables, n’ont pas cessé d’évoluer depuis leur création et sont désormais utilisés dans des systèmes complets (Xilinx Zynq ou Altera Stratix). Malgré tout, il reste de nombreux champs applicatifs desquels ils sont absents, et à tort. Utiliser les FPGA de manière plus intense au sein de systèmes complets est possible, mais il faut pour cela développer les capacités multi-utilisateurs de ces plateformes. Donner la capacité à une application s’exécutant sur un FPGA de se stopper pour, par exemple, laisser s’exécuter d’autres applications jugées prioritaires est particulièrement intéressant. Une telle action est qualifiée de « changement de contexte » (en anglais context-switch).Dans cet article, nous présentons une méthode et un outil permettant de donner cette capacité à des circuits fonctionnant sur cible reconfigurable. Le flot de conception présenté s’appuie sur un logiciel de synthèse de haut niveau et offre automatiquement la capacité de commutation aux circuits synthétisés. Les expériences menées sur un panel de circuits classiques montrent que l’ajout de cette capacité à un coût relativement faible ainsi qu’une rapidité de commutation sans égale dans la littérature

Evidence for a role of Arabidopsis CDT1 proteins in gametophyte development and maintenance of genome integrity

Meristems retain the ability to divide throughout the life cycle of plants, which can last for over 1000 years in some species. Furthermore, the germline is not laid down early during embryogenesis but originates from the meristematic cells relatively late during development. Thus, accurate cell cycle regulation is of utmost importance to avoid the accumulation of mutations during vegetative growth and reproduction. The Arabidopsis thaliana genome encodes two homologs of the replication licensing factor CDC10 Target1 (CDT1), and overexpression of CDT1a stimulates DNA replication. Here, we have investigated the respective functions of Arabidopsis CDT1a and CDT1b. We show that CDT1 proteins have partially redundant functions during gametophyte development and are required for the maintenance of genome integrity. Furthermore, CDT1-RNAi plants show endogenous DNA stress, are more tolerant than the wild type to DNA-damaging agents, and show constitutive induction of genes involved in DNA repair. This DNA stress response may be a direct consequence of reduced CDT1 accumulation on DNA repair or may relate to the ability of CDT1 proteins to form complexes with DNA polymerase e, which functions in DNA replication and in DNA stress checkpoint activation. Taken together, our results provide evidence for a crucial role of Arabidopsis CDT1 proteins in genome stability

Atmospheric CO₂ fluxes in a highly polluted estuary (the Scheldt)

Dissolved CO2 concentration and exchange with the atmosphere were investigated simultaneously in the Scheldt estuary. CO2 partial pressures as high as 5,700 µatm, corresponding to oversaturation with respect to the atmosphere of 1,600%, were observed in the upper estuary. The corresponding atmospheric CO2 fluxes reached values of up to 1.2 mol m-2 d-1. The estimated flux for the entire estuary amounts to 600 t of C d-1 for a river discharge of 6 m3 d-1

Carbon fluxes in coral reefs. II. Eulerian study of inorganic carbon dynamics and measurement of air-sea CO₂ exchanges

Air-sea CO2 exchanges and the partial pressure of CO2 were measured in surface water overlying 2 coral reefs: Moorea (French Polynesia, austral winter, August 1992), where coral diversity and surface cover are low, and Yonge Reef (Great Barrier Reef, austral summer, December 1993), where coral diversity and cover are comparatively higher. A procedure is proposed to estimate the potential CO2 exchange with the atmosphere by taking into account both the saturation level of oceanic seawater and the equilibration process occurring after water leaves the reef. It is shown that both sites were net sources of CO2 to the atmosphere as a result of the effect of calcification on the dynamics of the inorganic carbon system. The potential global CO2 evasion from the ocean to the atmosphere is about 4 times higher at Yonge Reef than at Moorea. It is also demonstrated that, at both sites, the major exchange of CO2 from sea to air occurs as seawater returns to chemical equilibrium after it has crossed and left the reef. The dynamics of inorganic carbon were studied using the so-called homogeneous buffer factor [beta = dln(pCO(2))/dln(DIC)] (where pCO(2) is the CO2 partial pressure in surface water and DIC is dissolved inorganic carbon), which gave estimates that approximately 80% of the change in inorganic carbon was related to photosynthesis and respiration. This approach showed that the calcification rate was proportional to the net organic production during the day and to the respiration rate at night

Ploidy Level and Genome Size of Vincetoxicum nigrum and V.rossicum (Apocynaceae), Two Invasive Vines in North Americ

Vincetoxicum nigrum (L.) Moench (black swallow-wort) and V. rossicum (Kleopow) Barbarich (pale swallow-wort) (Apocynaceae) are perennial vines that are targeted for classical biological control as a result of their massive invasion in natural areas and horticultural nurseries in the U.S. and Canada. Native ranges of V. nigrum and V. rossicum are limited to southwestern Europe and to Ukraine-southwestern Russia, respectively. The evolutionary mechanisms that have facilitated the range expansion since their introduction 150 years ago into North America have yet to be understood. In this study we examine two characteristics of the genome organization, i) the most frequently assessed ploidy level and ii) the variation in genome size, i.e., variation in the amount of DNA per monoploid set of chromosomes through loss or gain of repeated DNA sequences. Both can allow rapid changes in key phenotypic traits that enhance invasive ability. Flow cytometry using propidium iodide for the analysis of genome size variation and chromosome counting using DAPI were conducted on plants sampled from the introduced and native ranges of both species. In V. nigrum, accessions from Southern France and North America were all tetraploid (2n = 4x = 44). In V. rossicum, accessions from Russia and North America were all diploid (2n = 2x = 22). The mean 2C value (±STD) of V. nigrum and V. rossicum is 1.44±0.03pg and 0.71±0.02pg, respectively. This is the first report of genome size for the genus. At the species level, no evidence for genome size variation was found between the two ranges. Our data indicate that the invasive spread of both species was not triggered by differences in ploidy level or genome size between native and introduced populations. Alternative explanations should be sought

HLS-Based Methodology for Fast Iterative Development Applied to Elliptic Curve Arithmetic

International audienceHigh-Level Synthesis (HLS) is used by hardware developers to achieve higher abstraction in circuit descriptions. In order to shorten the hardware development time via HLS, we present an adjustment of the Iterative and Incremental Design (IID) methodology, frequently used in software development. In particular, our methodology is relevant for the development of applications with unusual complexity: the method was applied here to the development of large modular arithmetic, commonly used for cryptography applications (e.g., Elliptic Curves). Rapid feedback on circuit characteristics is used to evaluate deep architectural changes in short time, greatly reducing the time-to-market with respect to hand-made designs. In addition, our approach is highly flexible, since the same generic high-level description can be used to produce an entire set of circuits, each with different area/performance trade-offs. Thanks to the proposed approach, any change to the initial specification (e.g., the curve used) is also very fast, while it may require a large effort in the case of hand-made designs

A method addressing signal occlusion by scene objects to quantify the 3D distribution of forest components from terrestrial lidar

SilviLaser 2015, La Grande Motte, FRA, 28-/09/2015 - 30/09/2015International audienceEstimating exact 3D distribution of canopy components using terrestrial lidar in forest is limited by signal occlusion. We propose a method to address this limitation: it uses voxels, beam returns and beam propagation through the scene. The proposed method was validated using simulated forest scenes and a lidar simulator