444 research outputs found
6. Innover en sâinspirant de lâailleurs ?
CRĂER LES CONDITIONS FAVORABLES Ă LâINNOVATION QUâEST-CE QUE LâESPRIT DâINNOVATION ? Innover ne signifie pas tout rĂ©volutionner, cela consiste le plus souvent Ă sâinspirer de ce qui existe dĂ©jĂ , Ă en tirer matiĂšre Ă rĂ©flexion, Ă en emprunter des Ă©lĂ©ments pour rĂ©aliser une crĂ©ation unique, adaptĂ©e Ă un contexte spĂ©cifique, afin dâĂȘtre le plus « en phase » possible avec celui-ci. Câest le propos de ce chapitre : montrer comment on peut innover en sâinspirant de lâexemplaritĂ© de certaines biblio..
A primal-dual data-driven method for computational optical imaging with a photonic lantern
Optical fibres aim to image in-vivo biological processes. In this context,
high spatial resolution and stability to fibre movements are key to enable
decision-making processes (e.g., for microendoscopy). Recently, a single-pixel
imaging technique based on a multicore fibre photonic lantern has been
designed, named computational optical imaging using a lantern (COIL). A
proximal algorithm based on a sparsity prior, dubbed SARA-COIL, has been
further proposed to enable image reconstructions for high resolution COIL
microendoscopy. In this work, we develop a data-driven approach for COIL. We
replace the sparsity prior in the proximal algorithm by a learned denoiser,
leading to a plug-and-play (PnP) algorithm. We use recent results in learning
theory to train a network with desirable Lipschitz properties. We show that the
resulting primal-dual PnP algorithm converges to a solution to a monotone
inclusion problem. Our simulations highlight that the proposed data-driven
approach improves the reconstruction quality over variational SARA-COIL method
on both simulated and real data
Food intake of European adolescents in the light of different food-based dietary guidelines : results of the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) study
Objective: Since inadequate food consumption patterns during adolescence are not only linked with the occurrence of obesity in youth but also with the subsequent risk of developing diseases in adulthood, the establishment and maintenance of a healthy diet early in life is of great public health importance. Therefore, the aim of the present study was to describe and evaluate the food consumption of a well-characterized sample of European adolescents against food-based dietary guidelines for the first time.
Design: The HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) Study is a cross-sectional study, whose main objective was to obtain comparable data on a variety of nutritional and health-related parameters in adolescents aged 12.5-17.5 years.
Setting: Ten cities in Europe.
Subjects: The initial sample consisted of more than 3000 European adolescents. Among these, 1593 adolescents (54% female) had sufficient and plausible dietary data on energy and food intakes from two 24 h recalls using the HELENA-DIAT software.
Results: Food intake of adolescents in Europe is not optimal compared with the two food-based dietary guidelines, Optimized Mixed Diet and Food Guide Pyramid, examined in this study. Adolescents eat half of the recommended amount of fruit and vegetables and less than two-thirds of the recommended amount of milk (and milk products), but consume much more meat (and meat products), fats and sweets than recommended. However, median total energy intake may be estimated to be nearly in line with the recommendations.
Conclusion: The results urge the need to improve the dietary habits of adolescents in order to maintain health in later life
Quantifying diffuse and discrete venting at the Tour Eiffel vent site, Lucky Strike hydrothermal field
Author Posting. © American Geophysical Union, 2012. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry Geophysics Geosystems 13 (2012): Q04008, doi:10.1029/2011GC003991.The relative heat carried by diffuse versus discrete venting of hydrothermal fluids at mid-ocean ridges is poorly constrained and likely varies among vent sites. Estimates of the proportion of heat carried by diffuse flow range from 0% to 100% of the total axial heat flux. Here, we present an approach that integrates imagery, video, and temperature measurements to accurately estimate this partitioning at a single vent site, Tour Eiffel in the Lucky Strike hydrothermal field along the Mid-Atlantic Ridge. Fluid temperatures, photographic mosaics of the vent site, and video sequences of fluid flow were acquired during the Bathyluck'09 cruise (Fall, 2009) and the Momarsat'10 cruise (Summer, 2010) to the Lucky Strike hydrothermal field by the ROV Victor6000 aboard the French research vessel the âPourquoi Pasâ? (IFREMER, France). We use two optical methods to calculate the velocities of imaged hydrothermal fluids: (1) for diffuse venting, Diffuse Flow Velocimetry tracks the displacement of refractive index anomalies through time, and (2) for discrete jets, Particle Image Velocimetry tracks eddies by cross-correlation of pixel intensities between subsequent images. To circumvent video blurring associated with rapid velocities at vent orifices, exit velocities at discrete vents are calculated from the best fit of the observed velocity field to a model of a steady state turbulent plume where we vary the model vent radius and fluid exit velocity. Our results yield vertical velocities of diffuse effluent between 0.9 cm sâ1 and 11.1 cm sâ1 for fluid temperatures between 3°C and 33.5°C above that of ambient seawater, and exit velocities of discrete jets between 22 cm sâ1 and 119 cm sâ1 for fluid temperatures between 200°C and 301°C above ambient seawater. Using the calculated fluid velocities, temperature measurements, and photo mosaics of the actively venting areas, we calculate a heat flux due to diffuse venting from thin fractures of 3.15 ± 2.22 MW, discrete venting of 1.07 ± 0.66 MW, and, by incorporating previous estimates of diffuse heat flux density from Tour Eiffel, diffuse flux from the main sulfide mound of âŒ15.6 MW. We estimate that the total integrated heat flux from the Tour Eiffel site is 19.82 ± 2.88 MW and that the ratio of diffuse to discrete heat flux is âŒ18. We discuss the implication of these results for the characterization of different vent sites within Lucky Strike and in the context of a compilation of all available measurements of the ratio of diffuse to discrete heat flux.E. Mittelstaedt was supported
by the International Research Fellowship Program of the U.S.
National Science Foundation (OISE-0757920). Funding for the
2006, 2008, 2009, and 2010 cruises was provided by CNRS/
IFREMER through the MoMAR program (France), by ANR
(France), the Mothseim Project NT05â3 42213 to J. EscartĂn
and by grant CTM2010â15216/MAR from the Spanish Ministry
of Science to R. Garcia and J. EscartĂn. T. Barreyre was supported
by University Paris Diderot (Paris 7 â France) and
Institut de Physique du Globe de Paris (IPGP, France).2012-10-1
Hydrothermal activity along the slow-spreading Lucky Strike ridge segment (Mid-Atlantic Ridge) : distribution, heatflux, and geological controls
Author Posting. © The Author(s), 2015. This is the author's version of the work. It is posted here by permission of Elsevier for personal use, not for redistribution. The definitive version was published in Earth and Planetary Science Letters 431 (2015): 1730185, doi:10.1016/j.epsl.2015.09.025.We have reviewed available visual information from the seafloor, and recently acquired
microbathymetry for several traverses across the Lucky Strike segment, to evaluate the
distribution of hydrothermal activity. We have identified a new on-axis site with diffuse
flow, Ewan, and anactive vent structure ~1.2 km from the axis, Capelinhos. These sites
are minor relative to the Main field, and our total heatflux estimate for all active sites
(200-1200 MW) is only slightly higher than previously published estimates. We also
identify fossil sites W of the main Lucky Strike field. A circular feature ~200 m in
diameter located on the flanks of a rifted off-axis central volcano, is likely a large and
inactive hydrothermal edifice, named Grunnus. We find no indicator of focused
hydrothermal activity elsewhere along the segment, suggesting that the enhanced melt
supply and the associated melt lenses, required to form central volcanoes, also sustain
hydrothermal circulation to form and maintain large and long-lived hydrothermal fields.
Hydrothermal discharge to the seafloor occurs along fault traces, suggesting focusing of
hydrothermal circulation in the shallow crust along permeable fault zones.This work has been partly financed by ANR (France) Mothseim
Project NT05-3 42213 toJE, and by EU-RTN-MOMARNET to MC. The French Ministry of
Research financed ship, ROV and AUV time (Graviluckâ06, MOMARâ08, Bathyluckâ09,
MOMARSAT cruises in 2010-2015
Partial restoration of brain dystrophin by tricyclo-DNA antisense oligonucleotides alleviates emotional deficits in mdx52 mice
The mdx52 mouse model recapitulates a frequent mutation profile associated with brain involvement in Duchenne muscular dystrophy. Deletion of exon 52 impedes expression of two dystrophins (Dp427, Dp140) expressed in brain, and is eligible for therapeutic exon-skipping strategies. We previously showed that mdx52 mice display enhanced anxiety and fearfulness, and impaired associative fear learning. In this study, we examined the reversibility of these phenotypes using exon 51 skipping to restore exclusively Dp427 expression in the brain of mdx52 mice. We first show that a single intracerebroventricular administration of tricyclo-DNA antisense oligonucleotides targeting exon 51 restores 5%-15% of dystrophin protein expression in the hippocampus, cerebellum, and cortex, at stable levels between 7 and 11Â week after injection. Anxiety and unconditioned fear were significantly reduced in treated mdx52 mice and acquisition of fear conditioning appeared fully rescued, while fear memory tested 24Â h later was only partially improved. Additional restoration of Dp427 in skeletal and cardiac muscles by systemic treatment did not further improve the unconditioned fear response, confirming the central origin of this phenotype. These findings indicate that some emotional and cognitive deficits associated with dystrophin deficiency may be reversible or at least improved by partial postnatal dystrophin rescue
Networking to Optimize Dmd exon 53 Skipping in the Brain of mdx52 Mouse Model
Duchenne muscular dystrophy (DMD) is caused by mutations in the DMD gene that disrupt the open reading frame and thus prevent production of functional dystrophin proteins. Recent advances in DMD treatment, notably exon skipping and AAV gene therapy, have achieved some success aimed at alleviating the symptoms related to progressive muscle damage. However, they do not address the brain comorbidities associated with DMD, which remains a critical aspect of the disease. The mdx52 mouse model recapitulates one of the most frequent genetic pathogenic variants associated with brain involvement in DMD. Deletion of exon 52 impedes expression of two brain dystrophins, Dp427 and Dp140, expressed from distinct promoters. Interestingly, this mutation is eligible for exon skipping strategies aimed at excluding exon 51 or 53 from dystrophin mRNA. We previously showed that exon 51 skipping can restore partial expression of internally deleted yet functional Dp427 in the brain following intracerebroventricular (ICV) injection of antisense oligonucleotides (ASO). This was associated with a partial improvement of anxiety traits, unconditioned fear response, and Pavlovian fear learning and memory in the mdx52 mouse model. In the present study, we investigated in the same mouse model the skipping of exon 53 in order to restore expression of both Dp427 and Dp140. However, in contrast to exon 51, we found that exon 53 skipping was particularly difficult in mdx52 mice and a combination of multiple ASOs had to be used simultaneously to reach substantial levels of exon 53 skipping, regardless of their chemistry (tcDNA, PMO, or 2'MOE). Following ICV injection of a combination of ASO sequences, we measured up to 25% of exon 53 skipping in the hippocampus of treated mdx52 mice, but this did not elicit significant protein restoration. These findings indicate that skipping mouse dystrophin exon 53 is challenging. As such, it has not yet been possible to answer the pertinent question whether rescuing both Dp427 and Dp140 in the brain is imperative to more optimal treatment of neurological aspects of dystrophinopathy
PROSE: a PYTHON framework for modular astronomical images processing
peer reviewedTo reduce and analyse astronomical images, astronomers can rely on a wide range of libraries providing low-level implementations of legacy algorithms. However, combining these routines into robust and functional pipelines requires a major effort that often ends up in instrument-specific and poorly maintainable tools, yielding products that suffer from a low level of reproducibility and portability. In this context, we present PROSE, a PYTHON framework to build modular and maintainable image processing pipelines. Built for astronomy, it is instrument-agnostic and allows the construction of pipelines using a wide range of building blocks, pre-implemented or user-defined. With this architecture, our package provides basic tools to deal with common tasks, such as automatic reduction and photometric extraction. To demonstrate its potential, we use its default photometric pipeline to process 26 TESS candidates follow-up observations and compare their products to the ones obtained with ASTROIMAGEJ, the reference software for such endeavours. We show that PROSE produces light curves with lower white and red noise while requiring less user interactions and offering richer functionalities for reporting
Scaling-up energy sufficiency on a European level through a bottom-up modelling approach : lessons and perspectives
The unprecedented challenge of reaching carbon neutrality before mid-century and a large share of it within 2030 in order to keep under the 1.5 or 2 °C carbon budgets, requires broad and deep changes in production and consumption patterns which, together with a shift to renewables and reinforced efficiency, need to be addressed through energy sufficiency. However, inadequate representations and obstacles to characterising and identifying sufficiency potentials often lead to an underrepresentation of sufficiency in models, scenarios and policies.
One way to tackle this issue is to work on the development of sufficiency assumptions at a concrete level where various implications such as social consequences, environmental co-benefits, conditions for implementation can be discussed. This approach has been developed as the backbone of a collaborative project, gathering partners in 20 European countries at present, aiming for the integration of harmonised national scenarios into an ambitious net-zero European vision.
The approach combines a qualitative discussion on the role of energy sufficiency in a "systemic" merit order for global sustainability, and a quantitative discussion of the level of sufficiency to be set to contribute to meeting 100 % renewables supply and net-zero emissions goals by 2050 at the latest. The latter is based on the use of a dashboard, which serves as a common descriptive framework for all national scenario trajectories and their comparison, with a view to harmonising and strengthening them through an iterative process.
A set of key sufficiency-related indicators have been selected to be included in the dashboard, while various interrelated infrastructural, economic, environmental, social or legal factors or drivers have been identified and mapped. This paves the way for strengthening assumptions through the elaboration of "sufficiency corridors" defining a convergent, acceptable and sustainable level of energy services in Europe. The process will eventually inform the potential for sufficiency policies through a better identification of leverages, impacts and co-benefits
Yeast Mitochondrial Biogenesis: A Role for the PUF RNA-Binding Protein Puf3p in mRNA Localization
The asymmetric localization of mRNA plays an important role in coordinating posttranscriptional events in eukaryotic cells. We investigated the peripheral mitochondrial localization of nuclear-encoded mRNAs (MLR) in various conditions in which the mRNA binding protein context and the translation efficiency were altered. We identified Puf3p, a Pumilio family RNA-binding protein, as the first trans-acting factor controlling the MLR phenomenon. This allowed the characterization of two classes of genes whose mRNAs are translated to the vicinity of mitochondria. Class I mRNAs (256 genes) have a Puf3p binding motif in their 3'UTR region and many of them have their MLR properties deeply affected by PUF3 deletion. Conversely, mutations in the Puf3p binding motif alter the mitochondrial localization of BCS1 mRNA. Class II mRNAs (224 genes) have no Puf3p binding site and their asymmetric localization is not affected by the absence of PUF3. In agreement with a co-translational import process, we observed that the presence of puromycin loosens the interactions between most of the MLR-mRNAs and mitochondria. Unexpectedly, cycloheximide, supposed to solidify translational complexes, turned out to destabilize a class of mRNA-mitochondria interactions. Classes I and II mRNAs, which are therefore transported to the mitochondria through different pathways, correlated with different functional modules. Indeed, Class I genes code principally for the assembly factors of respiratory chain complexes and the mitochondrial translation machinery (ribosomes and translation regulators). Class II genes encode proteins of the respiratory chain or proteins involved in metabolic pathways. Thus, MLR, which is intimately linked to translation control, and the activity of mRNA-binding proteins like Puf3p, may provide the conditions for a fine spatiotemporal control of mitochondrial protein import and mitochondrial protein complex assembly. This work therefore provides new openings for the global study of mitochondria biogenesis
- âŠ