Changes in the starch-protein interface depending on common wheat grain hardness revealed using atomic force microscopy

The Atomic Force Microscope tip was used to progressively abrade the surface of non-cutted starch granules embedded in the endosperm protein matrix in grain sections from wheat near-isogenic lines differing in the puroindoline b gene and thus hardness. In the hard near-isogenic wheat lines, starch granules exhibited two distinct profiles corresponding either to abrasion in the surrounding protein layer or the starch granule. An additional profile, only identified in soft lines, revealed a marked stop in the abrasion at the protein-starch transition similar to a lipid interface playing a lubricant role. It was related to the presence of both wild-type puroindolines, already suggested to act at the starch-protein interface through their association with polar lipids.This study revealed, for the first time, in situ differences in the nano-mechanical properties at the starch-protein interface in the endosperm of wheat grains depending on the puroindoline allelic status

Rushes summarization by IRIM consortium: redundancy removal and multi-feature fusion

International audienceIn this paper, we present the first participation of a consortium of French laboratories, IRIM, to the TRECVID 2008 BBC Rushes Summarization task. Our approach resorts to video skimming. We propose two methods to reduce redundancy, as rushes include several takes of scenes. We also take into account low and midlevel semantic features in an ad-hoc fusion method in order to retain only significant content

E4F1-mediated control of pyruvate dehydrogenase activity is essential for skin homeostasis.

The multifunctional protein E4 transcription factor 1 (E4F1) is an essential regulator of epidermal stem cell (ESC) maintenance. Here, we found that E4F1 transcriptionally regulates a metabolic program involved in pyruvate metabolism that is required to maintain skin homeostasis. E4F1 deficiency in basal keratinocytes resulted in deregulated expression of dihydrolipoamide acetyltransferase (Dlat), a gene encoding the E2 subunit of the mitochondrial pyruvate dehydrogenase (PDH) complex. Accordingly, E4f1 knock-out (KO) keratinocytes exhibited impaired PDH activity and a redirection of the glycolytic flux toward lactate production. The metabolic reprogramming of E4f1 KO keratinocytes associated with remodeling of their microenvironment and alterations of the basement membrane, led to ESC mislocalization and exhaustion of the ESC pool. ShRNA-mediated depletion of Dlat in primary keratinocytes recapitulated defects observed upon E4f1 inactivation, including increased lactate secretion, enhanced activity of extracellular matrix remodeling enzymes, and impaired clonogenic potential. Altogether, our data reveal a central role for Dlat in the metabolic program regulated by E4F1 in basal keratinocytes and illustrate the importance of PDH activity in skin homeostasis

IRIM at TRECVID 2011: Semantic Indexing and Instance Search

12 pages - TRECVID workshop notebook papers/slides available at http://www-nlpir.nist.gov/projects/tvpubs/tv.pubs.org.htmlInternational audienceThe IRIM group is a consortium of French teams work- ing on Multimedia Indexing and Retrieval. This paper describes its participation to the TRECVID 2011 se- mantic indexing and instance search tasks. For the semantic indexing task, our approach uses a six-stages processing pipelines for computing scores for the likeli- hood of a video shot to contain a target concept. These scores are then used for producing a ranked list of im- ages or shots that are the most likely to contain the tar- get concept. The pipeline is composed of the following steps: descriptor extraction, descriptor optimization, classification, fusion of descriptor variants, higher-level fusion, and re-ranking. We evaluated a number of dif- ferent descriptors and tried different fusion strategies. The best IRIM run has a Mean Inferred Average Pre- cision of 0.1387, which ranked us 5th out of 19 partic- ipants. For the instance search task, we we used both object based query and frame based query. We formu- lated the query in standard way as comparison of visual signatures either of object with parts of DB frames or as a comparison of visual signatures of query and DB frames. To produce visual signatures we also used two apporaches: the first one is the baseline Bag-Of-Visual- Words (BOVW) model based on SURF interest point descriptor; the second approach is a Bag-Of-Regions (BOR) model that extends the traditional notion of BOVW vocabulary not only to keypoint-based descrip- tors but to region based descriptors

IRIM at TRECVID2009: High Level Feature Extraction

International audienceThe IRIM group is a consortium of French teams working on Multimedia Indexing and Retrieval. This paper describes our participation to the TRECVID 2009 High Level Features detection task. We evaluated a large number of different descriptors (on TRECVID 2008 data) and tried different fusion strategies, in particular hierarchical fusion and genetic fusion. The best IRIM run has a Mean Inferred Average Precision of 0.1220, which is significantly above TRECVID 2009 HLF detection task median performance. We found that fusion of the classification scores from different classifier types improves the performance and that even with a quite low individual performance, audio descriptors can help

IRIM at TRECVID 2010: Semantic Indexing and Instance Search

International audienceThe IRIM group is a consortium of French teams working on Multimedia Indexing and Retrieval. This paper describes our participation to the TRECVID 2010 semantic indexing and instance search tasks. For the semantic indexing task, we evaluated a number of different descriptors and tried different fusion strategies, in particular hierarchical fusion. The best IRIM run has a Mean Inferred Average Precision of 0.0442, which is above the task median performance. We found that fusion of the classification scores from different classifier types improves the performance and that even with a quite low individual performance, audio descriptors can help. For the instance search task, we used only one of the example images in our queries. The rank is nearly in the middle of the list of participants. The experiment showed that HSV features outperform the concatenation of HSV and Edge histograms or the Wavelet features

Redécouverte du Carex echinodes (Cyperaceae) sur le territoire québécois

Carex echinodes (Fernald) P.E. Rothr., Reznicek & Hipp, inclus dans la section des Ovales Kunth, est une espèce difficile à distinguer des 2 autres espèces de carex du « complexe du C. tenera ». Il a été élevé au rang d’espèce en 2009 à la suite d’études de son ADN et de son nombre de chromosomes. Passé inaperçu dans la flore québécoise depuis plus de 100 ans, C. echinodes a récemment été localisé au Bois-de-Saraguay sur l’île de Montréal. Une recherche dans plusieurs herbiers révèle aussi que cette espèce a déjà été récoltée sur le territoire québécois sans jamais avoir été identifiée correctement. Pour aider à son identification, nous présentons les caractéristiques morphologiques et les habitats des 3 espèces de carex du « complexe du C. tenera ». Nous ajoutons une description détaillée du C. echinodes et un portrait de sa répartition géographique. Finalement, nous soulignons l’importance de la conservation des forêts urbaines et celle d’accorder dans les meilleurs délais un statut de rareté au C. echinodes

DIRTI — Dirty Tangible Interfaces

cote interne IRCAM: Savary12aNational audienceDirty Tangible Interfaces (DIRTI) are a new concept in interface design that forgoes the dogma of repeatability in favor of a richer and more complex experience, constantly evolving, never reversible, and infinitely modifiable. We built a prototype based on granular or liquid interaction material placed in a glass dish, that is analyzed by video tracking for its 3D relief. This relief, and the dynamic changes applied to it by the user, are interpreted as activation profiles to drive corpus-based concatenative sound synthesis, allowing one or more players to mold sonic landscapes and to plow through them in an inherently collaborative, expressive, and dynamic experience

Testing geologic assumptions and scenarios in carbonate exploration: Insights from integrated stratigraphic, diagenetic, and seismic forward modeling

International audienceCarbonates are considered complex, heterogeneous at all scales, and unfortunately often poorly seismically imaged. We propose a methodology based on forward modelling approaches to test the validity of common exploration assumptions (e.g. chronostratigraphic value of seismic reflectors) and of geological interpretations (e.g. stratigraphic correlations, depositional and diagenetic architecture) that are determined from a limited amount of data. The proposed workflow includes 4 main steps: 1) identification and quantification of the primary controls on carbonate deposition and the prediction of the carbonate stratigraphic architecture (through stratigraphic forward modelling), 2) identification of diagenetic processes and prediction of the spatial distribution of diagenetic products (diagenetic forward modelling), 3) quantification of the impact of diagenesis on acoustic and reservoir properties, and 4) computation of synthetic seismic models based on various scenarios of stratigraphic and diagenetic architectures and comparison with actual seismic. The likelihood of a given scenario is tested by quantifying the 2 misfit between the modeled versus the real seismic. This workflow illustrates the relevance of forward modelling approaches for building realistic models that can be shared by the various disciplines of carbonate exploration (sedimentology, stratigraphy, diagenesis, seismic, geo-modelling and reservoir)