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17094
01/04/2018

Design and evaluation of a smart insole: application for continuous monitoring of frail people at home

Y.CHARLON, E.CAMPO, D.BRULIN

S4M

Revue Scientifique : Expert Systems with Applications, Vol.95, pp.57-71, Avril 2018, DOI https://doi.org/10.1016/j.eswa.2017.11.024 , N° 17094

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Abstract

The objectives of this work are to develop a technological solution designed to support active aging of frail older individuals and to conduct a first evaluation of the devices. We wish to bring a reflection in the field of connected health by setting up a remote medical follow-up. In this context, the connected object presented in this article aims at implementation a longitudinal follow-up of the walk by a health professional. Continuous remote data analysis applies behavior learning methods by modeling walking habits and allows the detection of deviations by application of thresholds defined by the expert. We propose an instrumented shoe insole to provide such monitoring (number of steps, distance covered and gait speed). In this perspective, we designed a low power microelectronic device integrated into the thickness of an insole in order to demonstrate the technical feasibility of such a device in laboratory and in living conditions. The project called “FOOT-TEST” is funded by the DIRECCTE of the Midi-Pyrenees Region in France. This project brought together a manufacturer who specializes in the design of foot-care systems, geriatricians and our laboratory specialized in electronics to propose a technical solution adapted to frail individuals. Two smart insole prototypes have been produced and a first evaluation of the smart insole in real use conditions has been performed. According to user feedback, the smart insole seems to be much easier to use than commercial connected pedometers. Moreover, in terms of performance, the smart insole provides better results. In this paper, we present specifications of the device, technological choices and the design of two versions of the smart insole, methods used to measure desired settings, a first evaluation of the system and, finally, preliminary conclusions and work in progress.

141595
17312
01/01/2018

Growth, stability and decomposition of Mg 2 Si ultra-thin films on Si (100)

B.SARPI, R.ZIRMI, M.PUTERO, M.BOUSLAMA, A.HEMERYCK, S.VIZZINI

IM2NP, LATAGE, LSM, M3

Revue Scientifique : Applied Surface Science, Vol.423, N°Part B, pp.522-527, Janvier 2018 , N° 17312

Lien : https://hal.laas.fr/hal-01583845

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Abstract

Using Auger Electron Spectroscopy (AES), Scanning Tunneling Microscopy/Spectroscopy (STM/STS) and Low Energy Electron Diffraction (LEED), we report an in-situ study of amorphous magnesium silicide (Mg2Si) ultra-thin films grown by thermally enhanced solid-phase reaction of few Mg monolayers deposited at room temperature (RT) on a Si(100) surface. Silicidation of magnesium films can be achieved in the nanometric thickness range with high chemical purity and a high thermal stability after annealing at 150 °C, before reaching a regime of magnesium desorption for temperatures higher than 350 °C. The thermally enhanced reaction of one Mg monolayer (ML) results in the appearance of Mg2Si nanometric crystallites leaving the silicon surface partially uncovered. For thicker Mg deposition nevertheless, continuous 2D silicide films are formed with a volcano shape surface topography characteristic up to 4 Mg MLs. Due to high reactivity between magnesium and oxygen species, the thermal oxidation process in which a thin Mg2Si film is fully decomposed (0.75 eV band gap) into a magnesium oxide layer (6–8 eV band gap) is also reported.

140918
17097
11/12/2017

Approche méthodologique pluridisciplinaire pour l'observation de la prise en main de technologies numériques par des personnes âgées

N.VIGOUROUX, E.CAMPO, C.GRIMAUD, F.VELLA, E.BOUGEOIS

IRIT-UPS, S4M, AG2R La Mondiale, LERASS

Ouvrage (contribution) : Des services à la personne à la silver économie Comment accompagner le vieillissement de la population à domicile sur les territoires aujourd'hui et demain ?, éditions ems, N°ISBN 9791094033142, Décembre 2017, Chapitre 5, pp.103-120 , N° 17097

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Résumé

Les enjeux liés au vieillissement de la population sont désormais considérables pour notre pays puisque à l’horizon 2060, les personnes de 60 ans et plus pourraient représenter près de 30 % de la population totale selon Blanpain et Chardon (2010), soit plus de 20 millions d’individus. Même si l’espérance de vie et la qualité de vie se sont très fortement améliorées par rapport à l’après-guerre, cela pose et va poser plusieurs questions notamment : comment permettre le maintien à domicile des personnes âgées, de celles qui sont en perte d’autonomie voire dépendantes ? Le secteur des services à la personne se situe à un moment charnière de son évolution, en raison de la mise en oeuvre de la loi relative à l’Adaptation de la Société au Vieillissement (ASV) au cours de l’année 2016, laquelle cherche à apporter des réponses aux transformations démographiques actuellement en cours dans notre pays. Compte tenu de la complexité des enjeux que le vieillissement de la population soulève, il nous a semblé nécessaire de pouvoir croiser différents points de vue, compétences et expérimentations en suscitant un dialogue entre des disciplines scientifiques variées mais aussi avec des praticiens "du domicile". Dans ce sens, nous avons mis en place un comité éditorial qui a réuni 33 enseignants-chercheurs et professionnels, dont l’expertise a permis de couvrir les principales problématiques rencontrées par le secteur des services à la personne et, de manière plus large, la Silver Economie, gage, par là même, de la rigueur et de la qualité des chapitres présentés dans ce livre. Dans cet ouvrage, vous trouverez 8 chapitres qui ont été rédigés par 21 auteurs professionnels, enseignants-chercheurs et/ou docteurs concernant cinq grandes thématiques qui sont : les conditions de travail et la conciliation emploi-famille pour les métiers d’intervention au Québec ; la construction de parcours et la gouvernance de réseaux sur les territoires ; la professionnalisation de l’encadrement et du management des structures de services à la personne ; le recours aux gérontechnologies pour favoriser le maintien à domicile ; les limites d’appropriation voire les questions déontologiques, éthiques et juridiques que pose l’utilisation des gérontechnologies au domicile.

141735
16314
11/12/2017

Analysis of DNA replication by optical mapping in nanochannels

J.LACROIX, S.PELOFY, MC.BLATCHE, M.J.PILLAIRE, S.HUET, C.CHAPUIS, J.S.HOFFMAN, A.BANCAUD

MILE, I2C, TOUCAN, Rennes

Revue Scientifique : Small, Vol.12, N°43, pp.5963-5970, Décembre 2017, DOI 10.1002/smll.201503795 , N° 16314

Lien : https://hal.archives-ouvertes.fr/hal-01384735

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Abstract

DNA replication is essential to maintain genome integrity in S phase of the cell division cycle. Accumulation of stalled replication forks is a major source of genetic instability, and likely constitutes a key driver of tumorigenesis. The mechanisms of regulation of replication fork progression have therefore been extensively investigated, in particular with DNA combing, an optical mapping technique that allows the stretching of single molecules and the mapping of active region for DNA synthesis by fluorescence microscopy. DNA linearization in nanochannels has been successfully used to probe genomic information patterns along single chromosomes, and has been proposed to be a competitive alternative to DNA combing. Yet this conjecture remains to be confirmed experimentally. Here, two complementary techniques are established to detect the genomic distribution of tracks of newly synthesized DNA in human cells by optical mapping in nanochannels. Their respective advantages and limitations are compared, and applied them to detect deregulations of the replication program induced by the antitumor drug hydroxyurea. The developments here thus broaden the field of applications accessible to nanofluidic technologies, and can be used in the future as part for molecular diagnostics in the context of high throughput cancer drug screening.

141732
17438
08/12/2017

Pore cross-talk in colloidal filtration

O.LIOT, S.AKASH, P.BACCHIN, P.DURU, J.MORRIS, P.JOSEPH

MILE, LGC, IMFT, Levich Institute

Rapport LAAS N°17438, Décembre 2017, 7p.

Lien : https://hal.laas.fr/hal-01651843

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Abstract

Blockage of pores by particles is found in numerous industrial and natural processes, including filtration and oil extraction. We present experimental results of filtration through a linear array of ten channels with one dimension which is sub-micron. These silicon-glass nanoslits serve as model pores, through which a dilute dispersion of Brownian polystyrene spheres flows. The clog growth rate at fixed differential pressure is shown to systematically increase with the number of saturated (entirely clogged) pores, indicating that there is an interaction or " cross-talk " between the pores. This observation is interpreted using a model proposed here, based on the concept that the residual permeability allows a clog to act as a filter. A clogged pore is thus the source of a local increase of particle concentration adjacent to the pore, which then diffuses towards other pores. This phenomenon, evidenced and modelled here in one dimension, should be at play in two-dimensional membranes.

141701
17417
05/12/2017

Control of evaporation by geometry in capillary structures. From confined pillar arrays in a gap radial gradient to phyllotaxy-inspired geometry

C.CHEN, P.DURU, P.JOSEPH, S.GEOFFROY, M.PRAT

IMFT, MILE, LMDC

Revue Scientifique : Scientific Reports, Vol.7, N°1, 15110p., Décembre 2017 , N° 17417

Lien : https://hal.laas.fr/hal-01643395

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Abstract

Evaporation is a key phenomenon in the natural environment and in many technological systems involving capillary structures. Understanding the evaporation front dynamics enables the evaporation rate from microfluidic devices and porous media to be finely controlled. Of particular interest is the ability to control the position of the front through suitable design of the capillary structure. Here, we show how to design model capillary structures in microfluidic devices so as to control the drying kinetics. This is achieved by acting on the spatial organization of the constrictions that influence the invasion of the structure by the gas phase. Two types of control are demonstrated. The first is intended to control the sequence of primary invasions through the pore space, while the second aims to control the secondary liquid structures: films, bridges, etc., that can form in the region of pore space invaded by the gas phase. It is shown how the latter can be obtained from phyllotaxy-inspired geometry. Our study thus opens up a route toward the control of the evaporation kinetics by means of tailored capillary structures.

141637
17234
01/12/2017

DFT-D study of adsorption of diaminoethane and propylamine molecules on anatase (101) TiO 2 surface

A.HEMERYCK, A.MOTTA, C.LACAZE-DUFAURE, D.COSTA, P.MARCUS

M3, IRCP, CIRIMAT

Revue Scientifique : Applied Surface Science, Vol.426, pp.107-115, Décembre 2017 , N° 17234

Lien : https://hal.laas.fr/hal-01574752

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Abstract

The adsorption on anatase (101) TiO 2 surface of two model amines, diaminoethane (DAE) and propylamine (PPA), was investigated using Density Functional Theory-Dispersion included (DFT-D) calculations. The investigated coverage is ranging from 0.25 monolayer to full coverage (one amine molecule per surface Ti ion). Both interactions of the adsorbed layer with the anatase (101) TiO 2 surface and inter-molecular interactions are described. A structural transition from a bridge to a perpendicular structure is found for DAE when evolving from 0.25 monolayer to full coverage. At full coverage, a dense, ordered adhesive layer is formed. For DAE, at intermediate coverage, different isoenergetic configurations are found and structural transition from a bridge to a perpendicular structure is found. In contrast, the adsorption mode of PPA is more regular with only perpendicularly adsorbed molecules at all investigated coverages. Dispersion forces already account for 40% of the adsorption energy at low coverage (0.25 ML) and are the driving force for monolayer formation with a contribution of 60% up to 100% at high coverage. As revealed by molecular dynamics, the molecules can change their orientation towards the surface in a concerted way.

140521
17427
26/10/2017

Clogging of model pores with brownian particles

O.LIOT, P.BACCHIN, P.DURU, P.JOSEPH, J.MORRIS

MILE, LGC, IMFT, Levich Institute

Manifestation avec acte : International Conference on Miniaturized Systems for Chemistry and Life Sciences ( MicroTas ) 2017 du 22 octobre au 26 octobre 2017, Savannah (USA), Octobre 2017, 2p. , N° 17427

Lien : https://hal.laas.fr/hal-01644282

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Abstract

Pore clogging with Brownian particles is of wide interest in filtration processes. We perform experiments where model sub-micrometric pores are clogged using a Brownian suspension. We study the influence of the ionic strength on the clog formation dynamics. The erosion/drag force competition is also studied using a crossflow in the inlet channel. The way the clogs disintegrate after the clogging process provides some information about their structure, which can be composed of two or three " layers " – labile or not. INTRODUCTION This paper reports new results about model pores clogging with strongly Brownian particles. The accumulation of particles in a porous media is a complex process which involves DLVO, steric and hydrodynamic interactions. The clogging phenomenon may occur in inkjet printers or numerous other applications such as water filtration through a membrane. While the fouling of a membrane at the macroscopic scale is well understood, the investigations at the pore scale are still at their beginning [1]. Very recent works have used model microchannels to study the effect of different parameters, such as ionic strength or Péclet number (advection/diffusion competition) on the clogging of pores at the micrometer scale [2-4]. The sub-micron dimensions are still unexplored in spite of strong specificities (Brownian motion, system size comparable to scales of interaction), and relevance (0.2 µm being a typical industrial pore size). In this context, we study the clogging/unclogging of silicon-glass channels with Brownian particles. We focus particularly on the influence of ionic strength and the building/erosion processes using a crossflow imposed in the inlet microchannel.

141679
17366
16/10/2017

Capturing chromosome structural properties from their spatial and temporal fluctuations

A.BANCAUD, O.GADAL, K.BYSTRICKY

MILE, LBME

Ouvrage (contribution) : Epigenetics and Systems Biology, Elsevier, N°ISBN 9780128030752, Octobre 2017, Chapter 12, pp.239-263 , N° 17366

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Abstract

Epigenetics and Systems Biology highlights the need for collaboration between experiments and theoretical modeling that is required for successful application of systems biology in epigenetics studies. This book breaks down the obstacles which exist between systems biology and epigenetics researchers due to information barriers and segmented research, giving real-life examples of successful combinations of systems biology and epigenetics experiments. Each section covers one type of modeling and one set of epigenetic questions on which said models have been successfully applied. In addition, the book highlights how modeling and systems biology relate to studies of RNA, DNA, and genome instability, mechanisms of DNA damage signaling and repair, and the effect of the environment on genome stability.

141233
17333
28/09/2017

Real-time chromatin dynamics at the single gene level during transcription activation

T.GERMIER, S.KOCANOVA, N.WALTHER, A.BANCAUD, H.A.SHABAN, H.SELLOU, A.Z.POLITI, J.ELLENBERG, F.GALLARDO, K.BYSTRICKY

LBME, EMBL, MILE

Rapport LAAS N°17333, Septembre 2017, 30p.

Lien : https://hal.laas.fr/hal-01587450

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Abstract

Genome dynamics relate to regulation of gene expression, the most fundamental process in biology. Yet we still do not know whether the very process of transcription drives spatial organization and chromatin conformation at specific gene loci. To address this issue, we have optimized the ANCHOR/ParB DNA labeling system for real-time imaging and quantitative analysis of the dynamics of a single-copy transgene in human cells. Transcription of the transgene under the control of the endogenous Cyclin D1 promoter was induced by addition of 17beta-estradiol. Motion of the ANCHOR3-tagged DNA locus was recorded in the same cell prior to and during appearance of nascent mRNA visualized using the MS2 system. We found that transcription initiation resulted in rapid confinement of the mRNA-producing gene. The confinement was maintained even upon inhibition of pol2 elongation. It did not occur when recruitment of pol2 or transcription initiation was blocked by anti-estrogens or Triptolide. These results suggest that preinitiation complex formation and concomitant reorganization of the chromatin domain constrains freedom of movement of an induced gene's promoter within minutes. Confined diffusion reflects assembly of functional protein hubs and DNA processing during the rate-limiting steps of transcription.

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