Development of a wearable framework for body center of mass acceleration assessment in people with transfemoral amputation

The biomechanical study of the body center of mass (BCoM) may reveal crucial information about gait impairment in people with amputation (Al Abiad et al. 2020). The 3D kinetics of the BCoM are usua..

Investigating symmetry in amputee gait through the improved harmonic ratio: influence of the stride segmentation method

The quantification of gait symmetry is extremely important in several clinical contexts. Among the many indices used to describe gait symmetry, the Harmonic Ratio (HR), which is based on a stride-b..

Definition of an optimal model based on segments' contribution for the estimation of the acceleration of the center of mass in people with lower-limb amputation

In the context of rehabilitation of people with amputation, gait analysis provides information about gait alterations. In that perspective, the body center of mass (BCoM) trajectory, or its derivat..

Estimation of 3D Body Center of Mass Acceleration and Instantaneous Velocity from a Wearable Inertial Sensor Network in Transfemoral Amputee Gait: A Case Study

The analysis of the body center of mass (BCoM) 3D kinematics provides insights on crucial aspects of locomotion, especially in populations with gait impairment such as people with amputation. In this paper, a wearable framework based on the use of different magneto-inertial measurement unit (MIMU) networks is proposed to obtain both BCoM acceleration and velocity. The proposed framework was validated as a proof of concept in one transfemoral amputee against data from force plates (acceleration) and an optoelectronic system (acceleration and velocity). The impact in terms of estimation accuracy when using a sensor network rather than a single MIMU at trunk level was also investigated. The estimated velocity and acceleration reached a strong agreement (ρ > 0.89) and good accuracy compared to reference data (normalized root mean square error (NRMSE) 0.89, NRMSE ≤ 14.0% in the mediolateral direction). Conversely, only the vertical component of the BCoM kinematics was accurately captured when considering a single MIMU. These results suggest that inertial sensor networks may represent a valid alternative to laboratory-based instruments for 3D BCoM kinematics quantification in lower-limb amputees.Don de la Fédération des Amputés de Guerre de France auprès de l'INI/CERH (contrat doctoral) Bourse mobilité cotutelle Université Franco-Italienne, VINCI C2-88

Gait event detection using inertial measurement units in people with transfemoral amputation: a comparative study

In recent years, inertial measurement units (IMUs) have been proposed as an alternative to force platforms and pressure sensors for gait events (i.e., initial and final contacts) detection. While multiple algorithms have been developed, the impact of gait event timing errors on temporal parameters and asymmetry has never been investigated in people with transfemoral amputation walking freely on level ground. In this study, five algorithms were comparatively assessed on gait data of seven people with transfemoral amputation, equipped with three IMUs mounted at the pelvis and both shanks, using pressure insoles for reference. Algorithms’ performance was first quantified in terms of gait event detection rate (sensitivity, positive predictive value). Only two algorithms, based on shank mounted IMUs, achieved an acceptable detection rate (positive predictive value > 99%). For these two, accuracy of gait events timings, temporal parameters, and absolute symmetry index of stance-phase duration (SPD-ASI) were assessed. Whereas both algorithms achieved high accuracy for stride duration estimates (median errors: 0%, interquartile ranges < 1.75%), lower accuracy was found for other temporal parameters due to relatively high errors in the detection of final contact events. Furthermore, SPD-ASI derived from IMU-based algorithms proved to be significantly different to that obtained from insoles data. [Figure not available: see fulltext.].- INI/CERAH (contrat doctoral), financement par un don de la FAGF - Bourse VINCI C2-881 (mobilité cotutelle

Synthesis of Novel Tryptamine Derivatives and Their Biological Activity as Antitumor Agents

We synthesized five novel tryptamine derivatives characterized by the presence of an azelayl chain or of a 1,1,1-trichloroethyl group, in turn connected to another heterocyclic scaffold. The combination of tryptamin-, 1,1,1-trichloroethyl- and 2-aminopyrimidinyl- moieties produced compound 9 identified as the most active compound in hematological cancer cell lines (IC50 = 0.57–65.32 M). Moreover, keeping constant the presence of the tryptaminic scaffold and binding it to the azelayl moiety, the compounds maintain biological activity. Compound 13 is still active against hematological cancer cell lines and shows a selective effect only on HT29 cells (IC50 = 0.006 M) among solid tumor models. Compound 14 loses activity on all leukemic lines, while showing a high level of toxicity on all solid tumor lines tested (IC50 0.0015–0.469 M)

A quantitative approach for measuring the reservoir of latent HIV-1 proviruses.

A stable latent reservoir for HIV-1 in resting CD4+ T cells is the principal barrier to a cure1-3. Curative strategies that target the reservoir are being tested4,5 and require accurate, scalable reservoir assays. The reservoir was defined with quantitative viral outgrowth assays for cells that release infectious virus after one round of T cell activation1. However, these quantitative outgrowth assays and newer assays for cells that produce viral RNA after activation6 may underestimate the reservoir size because one round of activation does not induce all proviruses7. Many studies rely on simple assays based on polymerase chain reaction to detect proviral DNA regardless of transcriptional status, but the clinical relevance of these assays is unclear, as the vast majority of proviruses are defective7-9. Here we describe a more accurate method of measuring the HIV-1 reservoir that separately quantifies intact and defective proviruses. We show that the dynamics of cells that carry intact and defective proviruses are different in vitro and in vivo. These findings have implications for targeting the intact proviruses that are a barrier to curing HIV infection

The Microarcsecond Sky and Cosmic Turbulence

Radio waves are imprinted with propagation effects from ionized media through which they pass. Owing to electron density fluctuations, compact sources (pulsars, masers, and compact extragalactic sources) can display a wide variety of scattering effects. These scattering effects, particularly interstellar scintillation, can be exploited to provide *superresolution*, with achievable angular resolutions (<~ 1 microarcsecond) far in excess of what can be obtained by very long baseline interferometry on terrestrial baselines. Scattering effects also provide a powerful sub-AU probe of the microphysics of the interstellar medium, potentially to spatial scales smaller than 100 km, as well as a tracer of the Galactic distribution of energy input into the interstellar medium through a variety of integrated measures. Coupled with future gamma-ray observations, SKA observations also may provide a means of detecting fainter compact gamma-ray sources. Though it is not yet clear that propagation effects due to the intergalactic medium are significant, the SKA will either detect or place stringent constraints on intergalactic scattering.Comment: 20 pages, 8 figures in 8 PostScript files, to appear in "Science with the Square Kilometer Array," eds. C. Carilli and S. Rawlings, New Astronomy Reviews (Elsevier: Amsterdam

Olmi-Cappella – La Mugliunaccia

Le village, perché sur un éperon calcaire très escarpé, est divisé en deux secteurs. Une partie haute comprenant 3 ou 4 maisons ainsi qu’un réduit fortifié et une partie basse où l’on peut dénombrer 14 structures protégées par un rempart en pierres sèches percé d’une seule porte. La circulation à l’intérieur du village se faisait par des chemins grossièrement aménagés à même la roche ou soutenus par des murets. Le caractère accidenté du relief et l’exiguïté de cet espace intra muras ne permet..

Olmi-Cappella – La Mugliunaccia

L’étude du village médiéval de la Mugliunaccia s’est terminée en 1998 après quatre campagnes de fouilles archéologiques. Cinq des dix-huit maisons ont été explorées en totalité et un sondage a été effectué dans la tour arasée qui dominait le site. L’éperon calcaire de la Mugliunaccia, escarpé et difficile d’accès (altitude 654 m), a connu une première occupation datée par le radiocarbone de l’âge du Bronze (2009-1941 av. J.-C. - Ly-7811). Cet habitat, sans doute peu important, a été identifié..