Constrained Statistical Modelling of Knee Flexion from Multi-Pose Magnetic Resonance Imaging

© 1982-2012 IEEE.Reconstruction of the anterior cruciate ligament (ACL) through arthroscopy is one of the most common procedures in orthopaedics. It requires accurate alignment and drilling of the tibial and femoral tunnels through which the ligament graft is attached. Although commercial computer-Assisted navigation systems exist to guide the placement of these tunnels, most of them are limited to a fixed pose without due consideration of dynamic factors involved in different knee flexion angles. This paper presents a new model for intraoperative guidance of arthroscopic ACL reconstruction with reduced error particularly in the ligament attachment area. The method uses 3D preoperative data at different flexion angles to build a subject-specific statistical model of knee pose. To circumvent the problem of limited training samples and ensure physically meaningful pose instantiation, homogeneous transformations between different poses and local-deformation finite element modelling are used to enlarge the training set. Subsequently, an anatomical geodesic flexion analysis is performed to extract the subject-specific flexion characteristics. The advantages of the method were also tested by detailed comparison to standard Principal Component Analysis (PCA), nonlinear PCA without training set enlargement, and other state-of-The-Art articulated joint modelling methods. The method yielded sub-millimetre accuracy, demonstrating its potential clinical value

Synthesis of new 1- 2-azido-2-(2,4-dichlorophenyl)ethyl -1H/-imidazoles and in vitro evaluation of their antifungal activity

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A microsystem for air quality measurement in future housings

International audienceNowadays, about half of humanity is housed in cities, a number expected to rise up to more than 2/3 by 2050 . Whether such a prediction is accurate is not relevant, we already experience the major issue that breathing a reasonably pure indoor air is becoming. Analytical chemistry has thus tremendous challenges ahead, among which the ability to design sensing elements for continuous air quality monitoring in closed environments. Functional materials with specific optimized properties are a growing part of modern chemistry and such materials may lead to disruptive solution in the field of analytical chemistry. For instance, hybrid porous materials prepared by the Sol-Gel process may be turned into functional sensing materials through careful formulation and process control . Incorporating such materials into microsystems is one promising way to new sensing approaches but their integration for sensing purposes into microsystems is far from being straightforward, which probably explains that it has not been reported yet. We have developed a microsystem based on an innovative microfluidic design and functional materials integrations that allows for gas detection and is compatible with continuous air quality measurements. First, we will describe the specificity of its design concerning micro-reactors fabrication and sensing capability. The preparation of the microfluidic device from micro-milled brass molds, and the method for fast and neat preparation of hundreds of individual micro-reactors will be reviewed. Then, the keys steps necessary to integrate functional materials into this device, such as the control of gelation will be explained. Special emphasis will be put on the interesting materials behavior within the microsystem. Finally, we will demonstrate the ability of our microsystem to perform quantitative optical detection of one of the main indoor air pollutants: formaldehyde . Based on air quality regulation, we will discuss the possibility of using such air quality monitoring microsystems in housings

A Mutant Variant of E2F4 Triggers Multifactorial Therapeutic Effects in 5xFAD Mice

Alzheimer’s disease (AD) has a complex etiology, which requires a multifactorial approach for an efficient treatment. We have focused on E2 factor 4 (E2F4), a transcription factor that regulates cell quiescence and tissue homeostasis, controls gene networks affected in AD, and is upregulated in the brains of Alzheimer’s patients and of APP/PS1 and 5xFAD transgenic mice. E2F4 contains an evolutionarily conserved Thr-motif that, when phosphorylated, modulates its activity, thus constituting a potential target for intervention. In this study, we generated a knock-in mouse strain with neuronal expression of a mouse E2F4 variant lacking this Thr-motif (E2F4DN), which was mated with 5xFAD mice. Here, we show that neuronal expression of E2F4DN in 5xFAD mice potentiates a transcriptional program consistent with the attenuation of the immune response and brain homeostasis. This correlates with reduced microgliosis and astrogliosis, modulation of amyloid-β peptide proteostasis, and blocking of neuronal tetraploidization. Moreover, E2F4DN prevents cognitive impairment and body weight loss, a known somatic alteration associated with AD. We also show that our finding is significant for AD, since E2F4 is expressed in cortical neurons from Alzheimer patients in association with Thr-specific phosphorylation, as evidenced by an anti-E2F4/anti-phosphoThr proximity ligation assay. We propose E2F4DN-based gene therapy as a promising multifactorial approach against AD.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This work has been supported by grant SAF2015-68488-R funded by Ministerio de Economía y Competitividad, grant RTI2018-095030-B-I00 funded by MCIN/AEI/10.13039/501100011033 and “ERDF A way of making Europe,” and a R&D contract between CSIC and Tetraneuron. NLS holds a Torres Quevedo grant from Ministerio de Industria. MRL holds an Industrial Doctorate grant from Ministerio de Economía, Industria y Competitividad

Effects of the substrate temperature on the deposition of thin SiOx films by atmospheric pressure microwave plasma torch (TIA)

International audienceThe effect of surface temperature on the deposition of silicon oxide (SiOx) films with a non-thermal microwave axial injection torch (TIA) was investigated in an open air reactor. Argon was used as plasma gas and hexamethyldisiloxane (Si2O2C6H18) as silicon precursor. The parametric study reported here focuses on the influence of the substrate temperature on the morphological and chemical properties of the films deposited in the interval [0 °C-130 °C]. A similar effect of low and high surface temperature on the deposition process and on the microstructure of the deposited films was highlighted. Macroscopically, particles were promptly produced in the gas phase and incorporated to the film, which generates high surface roughness. Microscopically, FTIR results have shown a high carbon contamination of the deposited films at low and high temperatures, resulting in understoichiometric SiOx films. They have also demonstrated that an optimum growth window for smooth and particle free SiOx was to keep the surface temperature between 30 and 60 °C. Simple reaction mechanisms for powder formation and continuous silicon oxide thin films growth are suggested for each temperature ranges