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Experimental conductivity measurements, obtained on NMC532-based electrodes with markedly different porosities and made with percolating and non-percolating CB/PVdF phase, are compared with full-field numerical predictions. These ones are based on segmented nanotomography images and phase bulk properties and contain no tunable parameter. A good agreement between the calculated and measured transport properties is observed. 3D current density fields give insights on the microstructure impacts on the current density distribution. Ionic transport is dominated by low tortuosity micrometric channels. Results also highlight the presence of “dead areas” in porosity that are crossed by a very low ionic current showing that, at high rate, the effective porosity may reduce to the micrometric pore network. For electronic conductivity, the CB/PVdF mixture percolation threshold is evaluated at 6%–7% in volume. Even below this key value threshold, CB/PVdF aggregates significantly improve electronic conductivity by forming gateways between NMC clusters thus minimising the constriction resistances between them. The size of the representative volume element relative to electronic and ionic conductivities is also investigated. [ABSTRACT FROM AUTHOR]

Changes in skeletal muscle mass (SMM), total adipose tissue mass (TAT) or bone mineral density (BMD) have been described in patients with cancer undergoing various treatments; simultaneous variations of all 3 tissues has not been reported. Data were prospectively collected in a clinical study (NCT00489697) including patients with liver metastases of colorectal cancer who received 4 cycles of bevacizumab in combination with cytotoxic chemotherapy. Computerized tomography (CT) at baseline and after chemotherapy was used to quantify skeletal muscle and adipose tissue cross-sectional areas, and mean lumbar spine BMD using validated approaches. After exclusion of patients lacking adequate CT images or missing data, 72 subjects were included. Patients were 63% male, aged 63.2 ± 10.3 years, 100% had liver metastases and 54%, 24% and 22% respectively has 0, 1 and ≥2 extrahepatic metastases. 100% tolerated 4 cycles of treatment and none showed progressive disease at the end of treatment. The scan interval was 70 days (95% CI, 62.3 to 80.5). Thresholds for loss of tissue were defined as loss ≥ measurement error. 10% of patients showed no loss of any tissue and a further 43% lost one tissue (SMM, TAT or BMD); 47% of patients lost 2 tissues (16.5% lost SMM + TAT, 8% lost SMM + BMD, 10% lost TAT + BMD) or all 3 tissues (12.5%). Catabolic behavior (2 or 3 tissue loss vs 0 or 1 tissue loss) associated with disease burden, including unresectable primary tumor (p = 0.010), presence of extrahepatic (EH) metastases (p = 0.039) and number of EH metastases (p = 0.004). No association was found between the number of tissues lost and treatment response, which was uniformly high, or treatment toxicity, which was uniformly low. Multiple tissues can be measured in routine CT images and these show considerable inter-individual variation. Substantial losses in some individuals appear to associate with disease burden. [ABSTRACT FROM AUTHOR]

Asthma is a complex chronic inflammatory disease of the airways. Association studies between HLA and asthma were first reported in the 1970s, and yet, the precise role of HLA alleles in asthma is not fully understood. Numerous genome-wide association studies were recently conducted on asthma, but were always limited to simple genetic markers (single nucleotide polymorphisms) and not complex HLA gene polymorphisms (alleles/haplotypes), therefore not capturing the biological relevance of this complex locus for asthma pathogenesis. To run the first HLA -centric association study with asthma and specific asthma-related phenotypes in a large cohort of African-ancestry individuals. We collected high-density genomics data for the Consortium on Asthma among African-ancestry Populations in the Americas (N = 4993) participants. Using computer-intensive machine-learning attribute bagging methods to infer HLA alleles, and Easy-HLA to infer HLA 5-gene haplotypes, we conducted a high-throughput HLA-centric association study of asthma susceptibility and total serum IgE (tIgE) levels in subjects with and without asthma. Among the 1607 individuals with asthma, 972 had available tIgE levels, with a mean tIgE level of 198.7 IU/mL. We could not identify any association with asthma susceptibility. However, we showed that HLA-DRB1∗09:01 was associated with increased tIgE levels (P = 8.5 × 10−4; weighted effect size, 0.51 [0.15-0.87]). We identified for the first time an HLA allele associated with tIgE levels in African-ancestry individuals with asthma. Our report emphasizes that by leveraging powerful computational machine-learning methods, specific/extreme phenotypes, and population diversity, we can explore HLA gene polymorphisms in depth and reveal the full extent of complex disease associations. [ABSTRACT FROM AUTHOR]

The microstructures of Li-ion positive composite electrodes designed for EVs have been characterised at different scales and in particular by FIB/SEM nanotomography. These electrodes are composed of Li(Ni0.5Mn0.3Co0.2)O2, carbon black (CB), and polyvinylidene fluoride (PVdF). The component proportions in the electrodes and the electrode densities were varied. Specific image analysis tools have been developed to quantify the microstructure parameters that will influence the transport and exchange properties of ionic and electronic charges during battery operation. Different porosities have been highlighted, in particular the micrometric porosity which appears to be the most effective for the ion diffusion in the liquid electrolyte due to its low tortuosity and large intra-connectiviy. Different parallel paths for the transport of electrons in solid phases such as the CB/PVdF percolating network and a hybrid one consisting of CB/PVdF islands distributed on the NMC cluster surface and the NMC grains pertaining to these clusters. This last network can be effective when the CB/PVdF islands allow the electrons to short-circuit the resistive NMC grain boundaries. [ABSTRACT FROM AUTHOR]

L'échographie en rhumatologie s'est développée à partir des années 1990, à la fois pour le diagnostic et le suivi thérapeutique, mais aussi dans le développement de techniques infiltratives échoguidées. Depuis, son utilisation fait partie du quotidien du rhumatologue. Ce chapitre permet de passer en revue les différents aspects des gestes échoguidés en rhumatologie : les principales indications, les contre-indications et les effets indésirables à connaître, ainsi que les modalités pratiques : l'aspect technique et les voies d'abord et le choix du matériel (dérivés cortisonés, aiguilles, sondes). Since the 1990s, ultrasonography has been used in rheumatology practice for diagnostic and therapeutic purposes, especially with ultra-sound guided procedures. It is now used in every-day practice. This chapter aims at reviewing the different aspects of interventional ultrasound in rheumatology. We will describe the main indications and contra-indications, as well as the potential side effects. More technical aspects will explain the main techniques used in ultrasound-guided procedures, with the different materials that can be used (local corticosteroids, needles, probes). [ABSTRACT FROM AUTHOR]

The electronic conductivity, at the multiscale, of lithium-ion positive composite electrodes based on LiNi1/3Mn1/3Co1/3O2 and/or carbon-coated LiFePO4, carbon black and poly(vinylidene fluoride) mixture is modeled. The electrode microstructures are acquired numerically in 3D by X-ray tomography and FIB/SEM nanotomography and numerically segmented to perform electrostatic simulations using Fast Fourier Transform (FFT)method. Such simulations are easy and quick to perform because they are directly computed on the grid represented by the voxels in the 3D volumes. Numerical results are compared with experimental measurements of the multiscale electronic conductivity by broadband dielectric spectroscopy (BDS). A good prediction is realized for the bulk conductivities of the C/LiFePO4 phase and the CB/PVdF mixture. The combination of X-ray and FIB/SEM tomography, FFT simulation method, and BDS is thus well adapted to understand the influence of the electrode composition and microstructure on its electronic conductivity. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract The efficiency of calcium phosphate (CaP) bone substitutes can be improved by tuning their resorption rate. The influence of both crystal orientation and ion doping on resorption is here investigated for beta-tricalcium phosphate (β-TCP). Non-doped and Mg-doped (1 and 6 mol%) sintered β-TCP samples were immersed in acidic solution (pH 4.4) to mimic the environmental conditions found underneath active osteoclasts. The surfaces of β-TCP samples were observed after acid-etching and compared to surfaces after osteoclastic resorption assays. β-TCP grains exhibited similar patterns with characteristic intra-crystalline pillars after acid-etching and after cell-mediated resorption. Electron BackScatter Diffraction analyses, coupled with Scanning Electron Microscopy, Inductively Coupled Plasma–Mass Spectrometry and X-Ray Diffraction, demonstrated the influence of both grain orientation and doping on the process and kinetics of resorption. Grains with c -axis nearly perpendicular to the surface were preferentially etched in non-doped β-TCP samples, whereas all grains with simple axis (a , b or c) nearly normal to the surface were etched in 6 mol% Mg-doped samples. In addition, both the dissolution rate and the percentage of etched surface were lower in Mg-doped specimens. Finally, the alignment direction of the intra-crystalline pillars was correlated with the preferential direction for dissolution. Statement of significance The present work focuses on the resorption behavior of calcium phosphate bioceramics. A simple and cost-effective alternative to osteoclast culture was implemented to identify which material features drive resorption. For the first time, it was demonstrated that crystal orientation, measured by Electron Backscatter Diffraction, is the discriminating factor between grains, which resorbed first, and grains, which resorbed slower. It also elucidated how resorption kinetics can be tuned by doping β-tricalcium phosphate with ions of interest. Doping with magnesium impacted lattice parameters. Therefore, the crystal orientations, which preferentially resorbed, changed, explaining the solubility decrease. These important findings pave the way for the design of optimized bone graft substitutes with tailored resorption kinetics. [ABSTRACT FROM AUTHOR]