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This work is focused on the modification of the interphase zone in short flax fibres / polypropylene (PP) composites by a bio-inspired modification of fibres called "nanostructuration" that uses the adsorption of biomass by-products, i.e. cellulose nanocrystals (CNC) and xyloglucan (XG), to create hierarchical flax fibres. The wettability and interfacial adhesion study reveals a strong decrease in the polar character of CNC modified flax fibres, hence increasing the work of adhesion with PP. Moreover, combining XG/CNC modified interphases with MAPP coupling agent enhances the ultimate mechanical properties of biocomposites with higher tensile strength and work of rupture, and modifies failure mechanisms as revealed by in situ micro-mechanical tensile SEM experiments. Bio-based hierarchical composites inspired by naturally occurring nanostructures open a new path for the development of sustainable composites with enhanced structural properties., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Objective: To study cervix elastography measurement and its relation with pregnancy outcome., Design: A two year prospective longitudinal study evaluated cervical elasticity by HI-RTE (Hitachi real-time tissue elastography) imaging during three trimesters of pregnancy. The main outcome measure was elastography index the cervical elastogram color-coded., Results: Three hundred eighty seven measurements were realized among 72 pregnant women prospectively enrolled. In the first trimester, the elasticity index was significantly lower in women who subsequently had unfavorable outcome than in women who delivered at term (respectively, EI=0.51 (±0.04) and 0.59 (±0.02); P=0.037). The negative predictive value of posterior lip color (blue, blue-green=hard cervix) was high NPV=83.8 95% CI [68.8-92.4] in the first trimester (SE=64.7 95% CI [41.3-82.7]; SP=60.8 95% CI [47.1-72.9]; VPP=35.5 95% CI [21.1-53.1]). A first-trimester elasticity index threshold value ≤0.38 had a specificity of 98.0% and a NPV of 80.9% (Se 29.4%, PPV 83.3%). This index value, when combined with a cervical length less than or equal to 36mm, increased the risk of adverse outcome (HR 8.87 95% CI [3.22-23.7])., Conclusions: Cervical elastography index is associated with unfavorable obstetrical outcomes, independently of cervical length. The study was registered in ClinicalTrials.gov under Identifier number NCT01032564., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)