Comparison between the forces and moments applied on the residuum of above-knee amputees during daily life activities and walking

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Light Emission in Silicon from Carbon Nanotubes

The use of optics in microelectronic circuits to overcome the limitation of metallic interconnects is more and more considered as a viable solution. Among future silicon compatible materials, carbon nanotubes are promising candidates thanks to their ability to emit, modulate and detect light in the wavelength range of silicon transparency. We report the first integration of carbon nanotubes with silicon waveguides, successfully coupling their emission and absorption properties. A complete study of this coupling between carbon nanotubes and silicon waveguides was carried out, which led to the demonstration of the temperature-independent emission from carbon nanotubes in silicon at a wavelength of 1.3 {\mu}m. This represents the first milestone in the development of photonics based on carbon nanotubes on silicon

L'IMPLANTATION D'UN SYSTEME DE CONTROLE DE GESTION AU SEIN D'ENTREPRISES LIBERALES : CAS DES OFFICES DE NOTAIRES

Cet article étudie la problématique de l'implantation d'un système contrôle de gestion au sein d'entreprises libérales, au travers du cas de 350 offices de notaires. La question de recherche étudiée peut être résumée en ces termes : quels sont les apports d'un système de contrôle de gestion dans une entreprise libérale et quels sont les facteurs clés de succès de l'implantation d'un tel système ? Pour étudier cette question, la méthodologie de recherche choisie est « qualimétrique » conciliant modèle qualitatif et modèle quantitatif.contrôle de gestion; entreprise libérale; implantation; recherche-intervention qualimétrique

Evaluation de l'état hydrique d'un sol fin par méthodes électriques et électromagnétiques : application géotechnique

With respect to Geotechnics, and in particular earthworks, there is a need regarding the soil hydric state evaluation through methods which are non-destructive, effective and applicable to the site constraints. The use of electrical and electromagnetical methods from Applied Geophysics, which are integrated and quick to carry out, might answer to this need for soil characterising, levees and embankments monitoring and helping earthworks construction site. The laboratory studies on compacted soil specimens show that the effective electromagnetic parameters (electrical resistivity and dielectrical constant) are sensitive to soil state parameters, both gravimetric water content and dry density. This observation suggests that the combined use of electrical and electromagnetic methods could enable one to distinguish between the soil state parameters which are useful for geotechnics. The trends observed on controlled specimens are interpreted on the basis of a soil microstructural model constituted by clayed aggregates and the water distribution in soil. In order to apply the laws fromWith respect to Geotechnics, and in particular earthworks, there is a need regarding the soil hydric state evaluation through methods which are non-destructive, effective and applicable to the site constraints. The use of electrical and electromagnetical methods from Applied Geophysics, which are integrated and quick to carry out, might answer to this need for soil characterising, levees and embankments monitoring and helping earthworks construction site. The laboratory studies on compacted soil specimens show that the effective electromagnetic parameters (electrical resistivity and dielectrical constant) are sensitive to soil state parameters, both gravimetric water content and dry density. This observation suggests that the combined use of electrical and electromagnetic methods could enable one to distinguish between the soil state parameters which are useful for geotechnics. The trends observed on controlled specimens are interpreted on the basis of a soil microstructural model constituted by clayed aggregates and the water distribution in soil. In order to apply the laws from the laboratory, a further set of geophysical measurements are to be carried out on a test site at scale close to real site conditions but where the homogeneity, the geometry, the temperature, the compaction state and the water content are monitored. Further decametric test sites, at different soil sates, allow to evaluate the measurement tools sensitivity and to link up the results obtained from laboratory to real site ones. the laboratory, a further set of geophysical measurements are to be carried out on a test site at scale close to real site conditions but where the homogeneity, the geometry, the temperature, the compaction state and the water content are monitored. Further decametric test sites, at different soil sates, allow to evaluate the measurement tools sensitivity and to link up the results obtained from laboratory to real site ones.En Géotechnique, et plus particulièrement dans le domaine des Terrassements, il existe un besoin d'évaluation de l'état hydrique des sols par méthodes non destructives, efficaces et applicables avec les contraintes de site. L'utilisation des méthodes électriques et électromagnétiques issues de la Géophysique Appliquée, intégrantes et rapides à mettre en oeuvre, pourrait répondre à ce besoin pour la caractérisation des sols, le suivi de digues et de remblais et l'aide à l'exécution de chantiers. L'étude d'échantillons de sol compacté en laboratoire montre que les paramètres électromagnétiques « effectifs » mesurés (résistivité électrique et constante diélectrique) sont sensibles aux paramètres d'état des sols, à la fois à la teneur en eau massique et à la masse volumique sèche. Ceci suggère que l'utilisation combinée des méthodes électriques et électromagnétiques pourrait permettre de découpler les paramètres d'état des sols qui sont utiles en géotechnique. Les tendances obserÎes sur échantillons contrôlés sont interprétées en s'appuyant sur un modèle microstructural du sol constitué d'agrégats argileux et prenant en compte la distribution de l'eau dans le sol. Afin de pouvoir appliquer in situ les lois établies en laboratoire, des séries de mesures géophysiques sont réalisées sur un site test, à échelle et conditions réelles de chantier, mais dont l'homogénéité, la géométrie, la température, le degré de compactage et la teneur en eau sont contrôlés. Des planches d'essais décamétriques, à différents états du sol, permettent d'évaluer la sensibilité des techniques de mesures et de relier les résultats obtenus au laboratoire à ceux d'un site réel

Expression of phosphate transporters in optimized cell culture models for dental cells biomineralization

Phosphate is a key component of dental mineral composition. The physiological role of membrane proteins of dental cells is suspected to be crucial for mineralization mechanisms. Contrary to published data related to calcium, data on regulation of phosphate flux through membrane of mineralizing cells are scarce. To address this lack of data, we studied the expression of six membranous phosphate transporters in two dental cell lines: a rat odontoblastic cell line (M2H4) and a mouse ameloblastic cell line (ALC) for which we optimized the mineralizing culture conditions

A Linear Stochastic Model of Turbulent Cascades and Fractional Fields

Turbulent cascades characterize the transfer of energy injected by a random force at large scales towards the small scales. In hydrodynamic turbulence, when the Reynolds number is large, the velocity field of the fluid becomes irregular and the rate of energy dissipation remains bounded from below even if the fluid viscosity tends to zero. A mathematical description of the turbulent cascade is a very active research topic since the pioneering work of Kolmogorov in hydrodynamic turbulence and that of Zakharov in wave turbulence. In both cases, these turbulent cascade mechanisms imply power-law behaviors of several statistical quantities such as power spectral densities. For a long time, these cascades were believed to be associated with nonlinear interactions, but recent works have shown that they can also take place in a dynamics governed by a linear equation with a differential operator of degree 0. In this spirit, we construct a linear equation that mimics the phenomenology of energy cascades when the external force is a statistically homogeneous and stationary stochastic process. In the Fourier variable, this equation can be seen as a linear transport equation, which corresponds to an operator of degree 0 in physical space. Our results give a complete characterization of the solution: it is smooth at any finite time, and, up to smaller order corrections, it converges to a fractional Gaussian field at infinite time

Ultra strong coupling regime and plasmon-polaritons in parabolic semiconductor quantum wells

Ultra strong coupling is studied in a modulation-doped parabolic potential well coupled to an inductance-capacitance resonant circuit. In this system, in accordance to Kohn's theorem, strong reduction of the energy level separation caused by the electron-electron interaction compensates the depolarization shift. As a result, a very large ratio of 27% of the Rabi frequency to the center resonance frequency as well as a polariton gap of width 2? ? 670GHz are observed, suggesting parabolic quantum wells as the system of choice in order to explore the ultra-strong coupling regime

Cost-Effectiveness of Highly Active Antiretroviral Therapy in South Africa

BACKGROUND: Little information exists on the impact of highly active antiretroviral therapy (HAART) on health-care provision in South Africa despite increasing scale-up of access to HAART and gradual reduction in HAART prices. METHODS AND FINDINGS: Use and cost of services for 265 HIV-infected adults without AIDS (World Health Organization [WHO] stage 1, 2, or 3) and 27 with AIDS (WHO stage 4) receiving HAART between 1995 and 2000 in Cape Town were compared with HIV-infected controls matched for baseline WHO stage, CD4 count, age, and socioeconomic status, who did not receive antiretroviral therapy (ART; No-ART group). Costs of service provision (January 2004 prices, US$1 = 7.6 Rand) included local unit costs, and two scenarios for HAART prices for WHO recommended first-line regimens: scenario 1 used current South African public-sector ART drug prices of$730 per patient-year (PPY), whereas scenario 2 was based on the anticipated public-sector price for locally manufactured drug of $181 PPY. All analyses are presented in terms of patients without AIDS and patients with AIDS. For patients without AIDS, the mean number of inpatient days PPY was 1.08 (95$950 for the No-ART group versus $1,342 and$793 PPY for the HAART group for scenario 1 and 2, respectively, whereas the incremental cost per life-year gained (LYG) was $1,622 for scenario 1 and$675 for scenario 2. For patients with AIDS, mean inpatients days PPY was 2.04 (95% CI: 1.63–2.52) for the HAART versus 15.36 (95% CI: 13.97–16.85) for the No-ART group. Mean outpatient visits PPY was 7.62 (95% CI: 6.81–8.49) compared with 6.60 (95% CI: 5.69–7.62) respectively. Average service provision PPY was $3,520 for the No-ART group versus$1,513 and $964 for the HAART group for scenario 1 and 2, respectively, whereas the incremental cost per LYG was cost saving for both scenarios. In a sensitivity analysis based on the lower (25$1,557 to $1,772 for the group without AIDS and from cost saving to$111 for patients with AIDS. CONCLUSION: HAART is a cost-effective intervention in South Africa, and cost saving when HAART prices are further reduced. Our estimates, however, were based on direct costs, and as such the actual cost saving might have been underestimated if indirect costs were also included

The Phosphate Transporter PiT1 (Slc20a1) Revealed As a New Essential Gene for Mouse Liver Development

BACKGROUND: PiT1 (or SLC20a1) encodes a widely expressed plasma membrane protein functioning as a high-affinity Na(+)-phosphate (Pi) cotransporter. As such, PiT1 is often considered as a ubiquitous supplier of Pi for cellular needs regardless of the lack of experimental data. Although the importance of PiT1 in mineralizing processes have been demonstrated in vitro in osteoblasts, chondrocytes and vascular smooth muscle cells, in vivo evidence is missing. METHODOLOGY/PRINCIPAL FINDINGS: To determine the in vivo function of PiT1, we generated an allelic series of PiT1 mutations in mice by combination of wild-type, hypomorphic and null PiT1 alleles expressing from 100% to 0% of PiT1. In this report we show that complete deletion of PiT1 results in embryonic lethality at E12.5. PiT1-deficient embryos display severely hypoplastic fetal livers and subsequent reduced hematopoiesis resulting in embryonic death from anemia. We show that the anemia is not due to placental, yolk sac or vascular defects and that hematopoietic progenitors have no cell-autonomous defects in proliferation and differentiation. In contrast, mutant fetal livers display decreased proliferation and massive apoptosis. Animals carrying two copies of hypomorphic PiT1 alleles (resulting in 15% PiT1 expression comparing to wild-type animals) survive at birth but are growth-retarded and anemic. The combination of both hypomorphic and null alleles in heterozygous compounds results in late embryonic lethality (E14.5-E16.5) with phenotypic features intermediate between null and hypomorphic mice. In the three mouse lines generated we could not evidence defects in early skeleton formation. CONCLUSION/SIGNIFICANCE: This work is the first to illustrate a specific in vivo role for PiT1 by uncovering it as being a critical gene for normal developmental liver growth