Gait analysis of patients with knee osteoarthritis highlights a pathological mechanical pathway and provides a basis for therapeutic interventions

Knee osteoarthritis (OA) is a painful and incapacitating disease affecting a large portion of the elderly population, for which no cure exists. There is a critical need to enhance our understanding of OA pathogenesis, as a means to improve therapeutic options. Knee OA is a complex disease influenced by many factors, including the loading environment. Analysing knee biomechanics during walking - the primary cyclic load-bearing activity - is therefore particularly relevant. There is evidence of meaningful differences in the knee adduction moment, flexion moment and flexion angle during walking between non-OA individuals and patients with medial knee OA. Furthermore, these kinetic and kinematic gait variables have been associated with OA progression. Gait analysis provides the critical information needed to understand the role of ambulatory biomechanics in OA development, and to design therapeutic interventions. Multidisciplinary research is necessary to relate the biomechanical alterations to the structural and biological components of OA. Cite this article: Favre J, Jolles BM. Analysis of gait, knee biomechanics and the physiopathology of knee osteoarthritis in the development of therapeutic interventions. EFORT Open Rev 2016;1:368-374. DOI: 10.1302/2058-5241.1.000051

A birational mapping with a strange attractor: Post critical set and covariant curves

We consider some two-dimensional birational transformations. One of them is a birational deformation of the H\'enon map. For some of these birational mappings, the post critical set (i.e. the iterates of the critical set) is infinite and we show that this gives straightforwardly the algebraic covariant curves of the transformation when they exist. These covariant curves are used to build the preserved meromorphic two-form. One may have also an infinite post critical set yielding a covariant curve which is not algebraic (transcendent). For two of the birational mappings considered, the post critical set is not infinite and we claim that there is no algebraic covariant curve and no preserved meromorphic two-form. For these two mappings with non infinite post critical sets, attracting sets occur and we show that they pass the usual tests (Lyapunov exponents and the fractal dimension) for being strange attractors. The strange attractor of one of these two mappings is unbounded.Comment: 26 pages, 11 figure

Properties of cosmological filaments extracted from Eulerian simulations

Using a new parallel algorithm implemented within the VisIt framework, we analysed large cosmological grid simulations to study the properties of baryons in filaments. The procedure allows us to build large catalogues with up to∼3×104 filaments per simulated volume and to investigate the properties of cosmic filaments for very large volumes at high resolution (up to 3003 Mpc3 simulated with 20483 cells). We determined scaling relations for the mass, volume, length and temperature of filaments and compared them to those of galaxy clusters. The longest filaments have a total length of about 200 Mpc with a mass of several 1015 M⊙. We also investigated the effects of different gas physics. Radiative cooling significantly modifies the thermal properties of the warm-hot-intergalactic medium of filaments, mainly by lowering their mean temperature via line cooling. On the other hand, powerful feedback from active galactic nuclei in surrounding haloes can heat up the gas in filaments. The impact of shock-accelerated cosmic rays from diffusive shock acceleration on filaments is small and the ratio between cosmic ray and gas pressure within filaments is of the order of∼10-20 per cen

Step by step capping and strain state of GaN/AlN quantum dots studied by grazing incidence diffraction anomalous fine structure

The investigation of small size embedded nanostructures, by a combination of complementary anomalous diffraction techniques, is reported. GaN Quantum Dots (QDs), grown by molecular beam epitaxy in a modified Stranski-Krastanow mode, are studied in terms of strain and local environment, as a function of the AlN cap layer thickness, by means of grazing incidence anomalous diffraction. That is, the X-ray photons energy is tuned across the Ga absorption K-edge which makes diffraction chemically selective. Measurement of \textit{hkl}-scans, close to the AlN (30-30) Bragg reflection, at several energies across the Ga K-edge, allows the extraction of the Ga partial structure factor, from which the in-plane strain of GaN QDs is deduced. From the fixed-Q energy-dependent diffracted intensity spectra, measured for diffraction-selected iso-strain regions corresponding to the average in-plane strain state of the QDs, quantitative information regarding composition and the out-of-plane strain has been obtained. We recover the in-plane and out-of-plane strains in the dots. The comparison to the biaxial elastic strain in a pseudomorphic layer indicates a tendency to an over-strained regime.Comment: submitted to PR

INTEGRAL timing and localization performance

In this letter we report on the accuracy of the attitude, misalignment, orbit and time correlation which are used to perform scientific analyses of the INTEGRAL data. The boresight attitude during science pointings has an accuracy of 3 arcsec. At the center of the field, the misalignments have been calibrated leading to a location accuracy of 4 to 40 arcsec for the different instruments. The spacecraft position is known within 10 meters. The relative timing between instruments could be reconstructed within 10 microsec and the absolute timing within 40 microsec.Comment: 5 pages, 2 figures, accepted for publication in A+A letters, INTEGRAL special issu

Green Currents for Meromorphic Maps of Compact K\"ahler Manifolds

We consider the dynamics of meromorphic maps of compact K\"ahler manifolds. In this work, our goal is to locate the non-nef locus of invariant classes and provide necessary and sufficient conditions for existence of Green currents in codimension one.Comment: Statement of Theorem 1.5 is slightly improved. Proposition 5.2 and Theorem 5.3 are adde

TAC 2011 MultiLing pilot overview

The Text Analysis Conference MultiLing Pilot of 2011 posed a multi-lingual summarization task to the summarization community, aiming to quantify and measure the performance of multi-lingual, multi-document summarization systems. The task was to create a 240–250 word summary from 10 news texts, describing a given topic. The texts of each topic were provided in seven languages (Arabic, Czech, English, French, Greek, Hebrew, Hindi) and each participant generated summaries for at least 2 languages. The evaluation of the summaries was performed using automatic (AutoSummENG, Rouge) and manual processes (Overall Responsiveness score). The participating systems were 8, some of which providing summaries across all languages. This paper provides a brief description for the collection of the data, the evaluation methodology, the problems and challenges faced, and an overview of participation and corresponding results

Structural and magnetic properties of CoPt mixed clusters

In this present work, we report a structural and magnetic study of mixed Co58Pt42 clusters. MgO, Nb and Si matrix can be used to embed clusters, avoiding any magnetic interactions between particles. Transmission Electron Microscopy (TEM) observations show that Co58Pt42 supported isolated clusters are about 2nm in diameter and crystallized in the A1 fcc chemically disordered phase. Grazing Incidence Small Angle X-ray Scattering (GISAXS) and Grazing Incidence Wide Angle X-ray Scattering (GIWAXS) reveal that buried clusters conserve these properties, interaction with matrix atoms being limited to their first atomic layers. Considering that 60% of particle atoms are located at surface, this interactions leads to a drastic change in magnetic properties which were investigated with conventional magnetometry and X-Ray Magnetic Circular Dichro\"{i}sm (XMCD). Magnetization and blocking temperature are weaker for clusters embedded in Nb than in MgO, and totally vanish in silicon as silicides are formed. Magnetic volume of clusters embedded in MgO is close to the crystallized volume determined by GIWAXS experiments. Cluster can be seen as a pure ferromagnetic CoPt crystallized core surrounded by a cluster-matrix mixed shell. The outer shell plays a predominant role in magnetic properties, especially for clusters embedded in niobium which have a blocking temperature 3 times smaller than clusters embedded in MgO