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Sophie Neveu

Publications and source records attributed to Sophie Neveu.

3 recordsLinked to original sources

AI-Driven CT-based quantification, staging and short-term outcome prediction of COVID-19 pneumonia

Chest computed tomography (CT) is widely used for the management of Coronavirus disease 2019 (COVID-19) pneumonia because of its availability and rapidity. The standard of reference for confirming COVID-19 relies on microbiological tests but these tests might not be available in an emergency setting and their results are not immediately available, contrary to CT. In addition to its role for early diagnosis, CT has a prognostic role by allowing visually evaluating the extent of COVID-19 lung abnormalities. The objective of this study is to address prediction of short-term outcomes, especially need for mechanical ventilation. In this multi-centric study, we propose an end-to-end artificial intelligence solution for automatic quantification and prognosis assessment by combining automatic CT delineation of lung disease meeting performance of experts and data-driven identification of biomarkers for its prognosis. AI-driven combination of variables with CT-based biomarkers offers perspectives for optimal patient management given the shortage of intensive care beds and ventilators.

cs.CV

Nanoscale distribution of magnetic anisotropies in bimagnetic soft core-hard shell MnFe$_2$O$_4$@CoFe$_2$O$_4$ nanoparticles

The nanoscale distribution of magnetic anisotropies was measured in core@shell MnFe$_2$O$_4$@CoFe$_2$O$_4$ 7.0 nm particles using a combination of element selective magnetic spectroscopies with different probing depths. As this picture is not accessible by any other technique, emergent magnetic properties were revealed. The coercive field is not constant in a whole nanospinel. The very thin (0.5 nm) CoFe$_2$O$_4$ hard shell imposes a strong magnetic anisotropy to the otherwise very soft MnFe$_2$O$_4$ core: a large gradient in coercivity was measured inside the MnFe$_2$O$_4$ core with lower values close to the interface region, while the inner core presents a substantial coercive field (0.54 T) and a very high remnant magnetization (90% of the magnetization at saturation).

cond-mat.mtrl-sci

Synthesis of Fe3O4@CoFe2O4@MnFe2O4 trimagnetic core/shell/shell nanoparticles

We report the synthesis and characterization of original 'multishell' magnetic nanoparticles made of a soft core (magnetite) covered with two successive shells: a hard one (cobalt ferrite) and then a soft one (manganese ferrite). Our results show that contrary to expectations from simple models in which the coercivity of a bimagnetic core/shell nanoparticle depends simply on the proportion of soft and hard phases within that particle, the addition of a second shell made of a soft ferrite material enhances the coercivity. Taking into account the interactions between the shells themselves and the core may thus be necessary to understand the magnetic properties of such nanoparticles.

cond-mat.mtrl-sci