Une aide à l'interprétation de traces : application à l'amélioration de scénarios pédagogiques

Nous nous intéressons dans cet article à l'observation au sein d'un EIAH. Notre objectif est de comprendre le comportement des apprenants et, à plus long terme, d'améliorer les scénarios pédagogiques. Dans un premier temps, nous montrons comment récupérer des observations depuis différentes sources. Dans un second temps, nous proposons une méthode permettant de composer une trace à partir de ces observations. Cette trace reflète l'activité de l'apprenant et servira de base à l'interprétation de son comportement. Nous illustrons notre approche à travers une expérience réalisée sur un EIAH dédié

Visualisation et régulation de l'activité des apprenants dans un EIAH tracé

International audienceNotre travail de recherche se situe dans le domaine de l'analyse des traces d'usage des EIAH. Dans ce papier, nous présentons une interface de visualisation des traces qui permet au tuteur d'observer l'activité d'un groupe d'apprenants au sein d'un EIAH tracé. L'interface permet des rétroactions du tuteur vers les apprenants en interagissant directement avec l'interface de visualisation. Un prototype implémentant cette interface a été validé lors d'une expérimentation que nous présentons

Tracing helium isotope compositions from mantle source to fumaroles at Oldoinyo Lengai volcano, Tanzania

International audienceOldoinyo Lengai is the only volcano on Earth currently erupting natrocarbonatites, of which the source and genesis remain controversial. Cognate xenoliths and fumaroles were sampled at the summit of Oldoinyo Lengai, and deep crustal xenoliths from Oltatwa maar, in 2010 and 2014, after the 2007-2008 sub-Plinian eruption. The summit cognate xenoliths provide direct information on the isotopic composition of the mid-crustal magma chamber that was active during the 2007-2008 explosive eruption. Cognate xenolith-hosted pyroxenes from Oldoinyo Lengai have an average 3 He/ 4 He = 6.58 ± 0.46 R A , similar to values from nearby silicate volcanoes (4.95-7.30 R A), and reflecting a sub-continental lithospheric mantle (SCLM) signature. This similarity implies that Oldoinyo Lengai carbonatites form from a similar mantle reservoir as the nearby silicate volcanoes. We identify SCLM, metasomatized by fluids/melts derived from the depleted convective mantle, as the common source of magmas in the Arusha volcanic province. Fumarole measurements highlight that fumarolic 3 He/ 4 He values have been relatively constant since at least 1988, indicating that dramatic changes to the crater region morphology during the 2007-2008 eruption did not affect the architecture of the hydrothermal system, which is probably connected to the crustal magma chamber(s). Moreover, the similarity between 3 He/ 4 He values from the mid-crustal magma chamber (6.58 ± 0.46 R A) and fumaroles (7.31 ± 0.24 R A) of Oldoinyo Lengai attests that helium is not subjected to atmospheric contamination or crustal assimilation during transport to the surface

SPACE: Enhancing Life on Earth. Proceedings Report

The proceedings of the 12th National Space Symposium on Enhancing Life on Earth is presented. Technological areas discussed include: Space applications and cooperation; Earth sensing, communication, and navigation applications; Global security interests in space; and International space station and space launch capabilities. An appendices that include featured speakers, program participants, and abbreviation & acronyms glossary is also attached

Exon skipping as a therapeutic strategy applied to an RYR1 mutation with pseudo-exon inclusion causing a severe core myopathy.

International audienceCentral core disease is a myopathy often arising from mutations in the type 1 ryanodine receptor (RYR1) gene, encoding the sarcoplasmic reticulum calcium release channel RyR1. No treatment is currently available for this disease. We studied the pathological situation of a severely affected child with two recessive mutations, which resulted in a massive reduction in the amount of RyR1. The paternal mutation induced the inclusion of a new in-frame pseudo-exon in RyR1 mRNA that resulted in the insertion of additional amino acids leading to the instability of the protein. We hypothesized that skipping this additional exon would be sufficient to restore RyR1 expression and to normalize calcium releases. We therefore developed U7-AON lentiviral vectors to force exon skipping on affected primary muscle cells. The efficiency of the exon skipping was evaluated at the mRNA level, at the protein level, and at the functional level using calcium imaging. In these affected cells, we observed a decreased inclusion of the pseudo-exon, an increased RyR1 protein expression, and a restoration of calcium releases of normal amplitude either upon direct RyR1 stimulation or in response to membrane depolarization. This study is the first demonstration of the potential of exon-skipping strategy for the therapy of central core disease, from the molecular to the functional level

Curbing methicillin-resistant Staphylococcus aureus in 38 French hospitals through a 15-year institutional control program

BACKGROUND: The Assistance Publique-Hôpitaux de Paris (AP-HP) institution administers 38 teaching hospitals (23 acute care and 15 rehabilitation and long-term care hospitals; total, 23 000 beds) scattered across Paris and surrounding suburbs in France. In the late 1980s, the proportion of methicillin resistance among clinical strains of Staphylococcus aureus (MRSA) reached approximately 40% at AP-HP.METHODS: A program aimed at curbing the MRSA burden was launched in 1993, based on passive and active surveillance, barrier precautions, training, and feedback. This program, supported by the strong commitment of the institution, was reinforced in 2001 by a campaign promoting the use of alcohol-based hand-rub solutions. An observational study on MRSA rate was prospectively carried out from 1993 onwards. RESULTS: There was a significant progressive decrease in MRSA burden (-35%) from 1993 to 2007, whether recorded as the proportion (expressed as percentage) of MRSA among S aureus strains (41.0% down to 26.6% overall; 45.3% to 24.2% in blood cultures) or incidence of MRSA cases (0.86 down to 0.56 per 1000 hospital days). The MRSA burden decreased more markedly in intensive care units (-59%) than in surgical (-44%) and medical (-32%) wards. The use of ABHR solutions (in liters per 1000 hospital days) increased steadily from 2 L to 21 L (to 26 L in acute care hospitals and to 10 L in rehabilitation and long-term care hospitals) following the campaign. CONCLUSION: A sustained reduction of MRSA burden can be obtained at the scale of a large hospital institution with high endemic MRSA rates, providing that an intensive program is maintained for a long period

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

La Lentille d'eau (Lemna minor) dans l'epuration tertiaire des eaux usees domestiques

CNRS-CDST / INIST-CNRS - Institut de l'Information Scientifique et TechniqueSIGLEFRFranc

Mies van der Rohe : genese du visible

Programme cite-projetsAvailable at INIST (FR), Document Supply Service, under shelf-number : RP 13070/1; RP 13070/2 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueSIGLEFRFranc