The French defence industry in the knowledge management era: A historical overview and evidence from empirical data

In the defence industry the recent development of ‘market for technology', the creation of new European high-technology companies as well as transformations in government agencies have conducted firms to reposition their technological and organisational skills. Our objective is to show that the transformations that have occurred in the past ten years have not only redefined skills and the organisation of production but have also given a more strategic place to knowledge management practices. Thus, we provide a contextual and historical overview with qualitative interviews in order to better understand the relation between KM and innovative behaviour in this industry. We have also built an original industrial and technological database with various samples that provides quantitative information concerning KM and innovative practices. The results of the statistical analysis reveal the specificity of firms in the defence industry. Taking into account the size of the firms and their technological intensity, we show that the behaviour of firms in the defence industry in terms of KM practices is different to that of other firms. The technological performances, the innovation intensity and the patent intensity also show the specificity of this industry. This structural tendency is explained as an innovative behaviour of the French NIS rather than as a mere “trend”Defence industry, Knowledge management practices, R&D, innovation, technological performance.

Safety Analysis of Parameterised Networks with Non-Blocking Rendez-Vous

We consider networks of processes that all execute the same finite-state protocol and communicate via a rendez-vous mechanism. When a process requests a rendez-vous, another process can respond to it and they both change their control states accordingly. We focus here on a specific semantics, called non-blocking, where the process requesting a rendez-vous can change its state even if no process can respond to it. In this context, we study the parameterised coverability problem of a configuration, which consists in determining whether there is an initial number of processes and an execution allowing to reach a configuration bigger than a given one. We show that this problem is EXPSPACE-complete and can be solved in polynomial time if the protocol is partitioned into two sets of states, the states from which a process can request a rendez-vous and the ones from which it can answer one. We also prove that the problem of the existence of an execution bringing all the processes in a final state is undecidable in our context. These two problems can be solved in polynomial time with the classical rendez-vous semantics

Precision of readout at the hunchback gene: analyzing short transcription time traces in living fly embryos

The simultaneous expression of the hunchback gene in the numerous nuclei of the developing fly embryo gives us a unique opportunity to study how transcription is regulated in living organisms. A recently developed MS2-MCP technique for imaging nascent messenger RNA in living Drosophila embryos allows us to quantify the dynamics of the developmental transcription process. The initial measurement of the morphogens by the hunchback promoter takes place during very short cell cycles, not only giving each nucleus little time for a precise readout, but also resulting in short time traces of transcription. Additionally, the relationship between the measured signal and the promoter state depends on the molecular design of the reporting probe. We develop an analysis approach based on tailor made autocorrelation functions that overcomes the short trace problems and quantifies the dynamics of transcription initiation. Based on live imaging data, we identify signatures of bursty transcription initiation from the hunchback promoter. We show that the precision of the expression of the hunchback gene to measure its position along the anterior-posterior axis is low both at the boundary and in the anterior even at cycle 13, suggesting additional post-transcriptional averaging mechanisms to provide the precision observed in fixed embryos

A highly conductive nanostructured PEDOT polymer confined into the mesoporous MIL-100(Fe)

[EN] Despite the higher efficiency, larger color range and faster stimulus response of polymeric electrochromic materials, their poor cyclability strongly hampers their application in optoelectronics. As an original strategy to stabilize and further nanostructure these polymers, herein an efficient encapsulation and in situ polymerization inside highly porous metal-organic frameworks (MOFs) is reported. In particular, the successful accommodation of poly(3,4-ethylendioxythiophene) (PEDOT) and its partially oxidized polarons inside the mesopores of the nontoxic iron trimesate MIL-100(Fe) is convincingly proved by a large panel of experimental techniques. Remarkably, the polymer-MOF interaction occurring for entrapped PEDOT within the pores (deeply assessed by experimental and simulation methods) might be responsible for the enhanced electrical conductivity of the resulting PEDOT@MIL-100(Fe) composite when compared to the insulating MIL-100(Fe) and the conductive free PEDOT. Furthermore, it was possible to observe the electrochromic properties of the PEDOT@MIL-100(Fe) composite, achieving an improved stability and good cyclability as a consequence of the effective protection by the MOF matrix.This work was supported by a 2017 Leonardo Grant for Researchers and Cultural Creators, BBVA Foundation (IN[17]_CBB_QUI_0197). The work was also partially supported by IMDEA Energy and Raphuel project (ENE2016-79608-C2-1-R, MINECOAEI/FEDER, UE). PH acknowledges the Spanish Ramon y Cajal Programme (grant agreement no. 2014-16823). S. N. thanks the Spanish Ministerio de Educacion, Cultura y Deporte for Jose Castillejo mobility programme (CAS14/00067) and financial support by Fundacion Ramon Areces (XVIII Concurso Nacional para la Adjudicacion de Ayudas a la Investigacion en Ciencias de la Vida y de la Materia, 2016). We also thank the synchrotron Soleil for providing access to the Cristal beamline.Salcedo-Abraira, P.; Santiago-Portillo, A.; Atienzar Corvillo, PE.; Bordet, P.; Salles, F.; Guillou, N.; Elkaim, E.... (2019). A highly conductive nanostructured PEDOT polymer confined into the mesoporous MIL-100(Fe). Dalton Transactions. 48(26):9807-9817. https://doi.org/10.1039/c9dt00917eS980798174826P. M. S. Monk , R. J.Mortimer and D. R.Rosseinsky , Electrochromism: fundamentals and applications , VCH , 1995Kondalkar, V. V., Kharade, R. R., Mali, S. S., Mane, R. M., Patil, P. B., Patil, P. S., … Bhosale, P. N. (2014). Nanobrick-like WO3 thin films: Hydrothermal synthesis and electrochromic application. Superlattices and Microstructures, 73, 290-295. doi:10.1016/j.spmi.2014.05.039Patil, C. E., Tarwal, N. L., Jadhav, P. R., Shinde, P. S., Deshmukh, H. P., Karanjkar, M. M., … Patil, P. S. (2014). Electrochromic performance of the mixed V2O5–WO3 thin films synthesized by pulsed spray pyrolysis technique. 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Tehnika kao čovjekova ekspanzija

Svrha tehnike kojom se čovjek svakodnevno služi jest olakšavanje života. Čovječji život drugačiji je od ostatka živog svijeta (životinje, biljke); zatvoren je u otvorenosti svijeta i prirode – u kulturi. Pritom tehnika koju čovjek koristi nisu samo oruđa i oružja. Od sredine 20. stoljeća povećava se broj istraživanja u području biotehnologije koja daje uvid u bolje razumijevanje biologije, genetike, a i antropologije, s obzirom na to da područje biotehnologije obuhvaća tehničke i prirodne znanosti. Razvoj biotehnologije zahvaljuje razvoju tehnike koja omogućuje bolji i precizniji uvid u njihove predmete promatranja. Snažni razvoj tehnike, osim pitanja vezanih uz prirodu nje same, donosi i pitanja vezana uz ljudsku prirodu, budući da je čovjek taj koji se koristi tehnikom. Tekst navodi cilj u otvorenosti i razmatranju pitanja vezanih uz probleme na relaciji čovjek – tehnika i njihova suodnosa, te nudi neka njegova viđenja; kakva je čovjekova prirodnost, kako je razvoj tehnike utjecao na njegovo viđenje budućeg svijeta te kako taj budući svijet (u odnosu na prošlo vrijeme) izgleda sada

A multinuclear NMR study of six forms of AlPO-34:structure and motional broadening

We report a study of the CHA-type aluminophosphate AlPO-34, prepared with six different structure-directing agents (SDAs): piperidine (pip), morpholine (mor), pyridine (pyr), 1,4,8,11-tetraazacyclotetradecane (cyclam), 1,3 dimethylimidazolium (dmim) chloride and 1-ethyl-3-methylimidazolium (emim) bromide. Using a combination of solid-state NMR spectroscopy, periodic density functional theory (DFT) calculations and synchrotron X-ray diffraction, we show that, even in crystallographically well-ordered materials such as AlPO-34 with dmim as the SDA, local disorder may be present. For such disordered structures, where it is challenging to use DFT to assign NMR spectra, we show that the 31P isotropic chemical shift can be predicted accurately using the mean P-O bond length and P-O-Al bond angle, in an extension of previous work. Variable-temperature 27Al NMR reveals the presence of microsecond-timescale dynamics in all forms of AlPO- 34, with two different motional regimes observed, depending on whether structural H2O is also present. H2O is detected in AlPO-34 prepared with mor as the SDA, although this material was previously reported as anhydrous, suggesting that this form of AlPO-34 may be hygroscopic despite the presence of the SDAs within the pores

De 20 000 à 18 000 BP en Quercy : apports de la séquence du Cuzoul de Vers à la compréhension de l'évolution des comportements socio-économiques entre Solutréen récent et Badegoulien

Essai de synthèse des travaux menés autour du gisement du Cuzoul de Vers (Lot)

Marine protist diversity in European coastal waters and sediments as revealed by high-throughput sequencing

International audienceAlthough protists are critical components of marine ecosystems, they are still poorly characterized. Here we analysed the taxonomic diversity of planktonic and benthic protist communities collected in six distant European coastal sites. Environmental deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) from three size fractions (pico-, nano- and micro/mesoplankton), as well as from dissolved DNA and surface sediments were used as templates for tag pyrosequencing of the V4 region of the 18S ribosomal DNA. Beta-diversity analyses split the protist community structure into three main clusters: picoplankton-nanoplankton-dissolved DNA, micro/mesoplankton and sediments. Within each cluster, protist communities from the same site and time clustered together, while communities from the same site but different seasons were unrelated. Both DNA and RNA-based surveys provided similar relative abundances for most class-level taxonomic groups. Yet, particular groups were overrepresented in one of the two templates, such as marine alveolates (MALV)-I and MALV-II that were much more abundant in DNA surveys. Overall, the groups displaying the highest relative contribution were Dinophyceae, Diatomea, Ciliophora and Acantharia. Also, well represented were Mamiellophyceae, Cryptomonadales, marine alveolates and marine stramenopiles in the picoplankton, and Monadofilosa and basal Fungi in sediments. Our extensive and systematic sequencing of geographically separated sites provides the most comprehensive molecular description of coastal marine protist diversity to date

Role of the Endogenous Antioxidant System in the Protection of Schistosoma mansoni Primary Sporocysts against Exogenous Oxidative Stress

Antioxidants produced by the parasite Schistosoma mansoni are believed to be involved in the maintenance of cellular redox balance, thus contributing to larval survival in their intermediate snail host, Biomphalaria glabrata. Here, we focused on specific antioxidant enzymes, including glutathione-S-transferases 26 and 28 (GST26 and 28), glutathione peroxidase (GPx), peroxiredoxin 1 and 2 (Prx1 and 2) and Cu/Zn superoxide dismutase (SOD), known to be involved in cellular redox reactions, in an attempt to evaluate their endogenous antioxidant function in the early-developing primary sporocyst stage of S. mansoni. Previously we demonstrated a specific and consistent RNA interference (RNAi)-mediated knockdown of GST26 and 28, Prx1 and 2, and GPx transcripts, and an unexpected elevation of SOD transcripts in sporocysts treated with gene-specific double-stranded (ds)RNA. In the present followup study, in vitro transforming sporocysts were exposed to dsRNAs for GST26 and 28, combined Prx1/2, GPx, SOD or green-fluorescent protein (GFP, control) for 7 days in culture, followed by assessment of the effects of specific dsRNA treatments on protein levels using semi-quantitative Western blot analysis (GST26, Prx1/2 only), and larval susceptibility to exogenous oxidative stress in in vitro killing assays. Significant decreases (80% and 50%) in immunoreactive GST26 and Prx1/2, respectively, were observed in sporocysts treated with specific dsRNA, compared to control larvae treated with GFP dsRNA. Sporocysts cultured with dsRNAs for GST26, GST28, Prx1/2 and GPx, but not SOD dsRNA, were significantly increased in their susceptibility to H2O2 oxidative stress (60–80% mortalities at 48 hr) compared to GFP dsRNA controls (∼18% mortality). H2O2-mediated killing was abrogated by bovine catalase, further supporting a protective role for endogenous sporocyst antioxidants. Finally, in vitro killing of S. mansoni sporocysts by hemocytes of susceptible NMRI B. glabrata snails was increased in larvae treated with Prx1/2, GST26 and GST28 dsRNA, compared to those treated with GFP or SOD dsRNAs. Results of these experiments strongly support the hypothesis that endogenous expression and regulation of larval antioxidant enzymes serve a direct role in protection against external oxidative stress, including immune-mediated cytotoxic reactions. Moreover, these findings illustrate the efficacy of a RNAi-type approach in investigating gene function in larval schistosomes

Observation of Microlensing towards the Galactic Spiral Arms: EROS II 3 year survey

We present an analysis of the light curves of 9.1 million stars observed during three seasons by EROS (Experience de Recherche d'Objets Sombres), in the Galactic plane away from the bulge. Seven stars exhibit luminosity variations compatible with gravitational microlensing effects due to unseen objects. The corresponding optical depth, averaged over four directions, is tau = 0.45 +0.24 -0.11 x 10^-6. While this value is compatible with expectations from simple galactic models under reasonable assumptions on the target distances, we find an excess of events with short timescale towards the direction closest to the Galactic Centre