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The Theory of Mathematical Working Spaces—Theoretical Characteristics
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R3-AFP score is a new composite tool to refine prediction of hepatocellular carcinoma recurrence after liver transplantation
No full textInternational audienceBackground & aims: Patients with hepatocellular carcinoma (HCC) are selected for liver transplantation (LT) based on pre-LT imaging ± alpha-foetoprotein (AFP) level, but discrepancies between pre-LT tumour assessment and explant are frequent. Our aim was to design an explant-based recurrence risk reassessment score to refine prediction of recurrence after LT and provide a framework to guide post-LT management.Methods: Adult patients who underwent transplantation between 2000 and 2018 for HCC in 47 centres were included. A prediction model for recurrence was developed using competing-risk regression analysis in a European training cohort (TC; n = 1,359) and tested in a Latin American validation cohort (VC; n=1,085).Results: In the TC, 76.4% of patients with HCC met the Milan criteria, and 89.9% had an AFP score of ≤2 points. The recurrence risk reassessment (R3)-AFP model was designed based on variables independently associated with recurrence in the TC (with associated weights): ≥4 nodules (sub-distribution of hazard ratio [SHR] = 1.88, 1 point), size of largest nodule (3-6 cm: SHR = 1.83, 1 point; >6 cm: SHR = 5.82, 5 points), presence of microvascular invasion (MVI; SHR = 2.69, 2 points), nuclear grade >II (SHR = 1.20, 1 point), and last pre-LT AFP value (101-1,000 ng/ml: SHR = 1.57, 1 point; >1,000 ng/ml: SHR = 2.83, 2 points). Wolber's c-index was 0.76 (95% CI 0.72-0.80), significantly superior to an R3 model without AFP (0.75; 95% CI 0.72-0.79; p = 0.01). Four 5-year recurrence risk categories were identified: very low (score = 0; 5.5%), low (1-2 points; 15.1%), high (3-6 points; 39.1%), and very high (>6 points; 73.9%). The R3-AFP score performed well in the VC (Wolber's c-index of 0.78; 95% CI 0.73-0.83).Conclusions: The R3 score including the last pre-LT AFP value (R3-AFP score) provides a user-friendly, standardised framework to design post-LT surveillance strategies, protocols, or adjuvant therapy trials for HCC not limited to the Milan criteria
The microwave spectrum of the difluorocyanomethyl radical, ĊF2CN
No full textInternational audienceThe pure rotational spectrum of the open shell difluorocyanomethyl radical, ĊF2CN, has been measured using two Balle-Flygare-type cavity Fourier-Transform-Microwave (FTMW) spectrometers both equipped with pulsed discharged nozzles. A total of 156 transitions (from N = 1-0 to 6-5, and Ka = 0, 1, 2, 3) in the electronic ground state were observed between 6.5 GHz and 38.4 GHz with a typical linewidth of ~5 kHz full-width-half-maximum. A Hamiltonian that included semi-rigid rotor, spin-rotation, and nuclear hyperfine parameters was fit to the observed data set and these parameters have been interpreted and compared to similar radicals. Excellent agreement between experimental and uB3LYP/aug-cc-pVQZ calculated rotational constants, the experimental inertial defect, −0.6858(2) uÅ2 , and the failure of a coupling scheme in which the fluorine nuclei are treated as identical and related by a C2v symmetry axis combine to indicate a nonplanar structure for the ĊF2CN radical
Les collectifs citoyens producteurs d’énergies renouvelables, acteurs économiques de la transition
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Introduction - Les enjeux de l’enseignement créatif du management
No full textInternational audienceCette introduction est pour nous l’occasion de vous dévoiler l’esprit qui anime notre groupe de recherche MACCA management : Méthodes et Approches Créatives et Critiques de l’Apprentissage du management. Ce livre est avant tout le fruit d’une réflexion collective et passionnée conduite à partir d’expériences pédagogiques engagées par des enseignants-chercheurs. Notre communauté a été officiellement créée en 2015 pour proposer une réflexion académique sur l’apprentissage du management tant sur le fond (quelles notions de management enseigner pour préparer au mieux les managers), que sur la forme (comment enseigner le management) afin d’amener les apprenants (étudiants, apprentis et managers en formation continue)1 à développer leur créativité et leur réflexivité. [...
Improved fracture resistance of 3D-printed elastoplastic structures with respect to their topology and orientation of deposited layers
No full textInternational audience3D-printed structures may be characterized by anisotropic fracture behavior because of their layered nature. Depending on the orientation of the sample during the layer deposition, a completely different mechanical response can be obtained, ranging from quasi-brittle to elastoplastic, and with large variations in the maximum stress to failure. In this study, an optimization framework is proposed for 3D-printed samples to maximize their resistance to fracture with respect to both the orientation of the deposited layers during the process and the topology of the sample. To achieve this, a phase-field anisotropic elastoplastic fracture model is combined with a Bidirectional Evolutionary Structural Optimization topology optimization. The model makes it possible to predict the response of the structure until failure with respect to the orientation of the deposited layers in the 3D-printing process and then optimize this orientation to maximize the mechanical response. A large increase in fracture resistance can be obtained by optimizing the orientation, and a significant increase in fracture resistance can be achieved using the present nonlinear anisotropic topology optimization compared with the use of linear topology optimization
Wet deposition in the remote western and central Mediterranean as a source of trace metals to surface seawater
No full textInternational audienceThis study reports the only recent characterization of two contrasted wet deposition events collected during the PEACETIME (ProcEss studies at the Air-sEa Interface after dust deposition in the MEditerranean Sea) cruise in the open Mediterranean Sea (Med Sea) and their impact on trace metal (TM) marine stocks. Rain samples were analysed for Al, 12 TMs (Co, Cd, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Ti, V and Zn) and nutrient (N, P, dissolved organic carbon) concentrations. The first rain sample collected in the Ionian Sea (Rain ION) was a typical regional background wet deposition event, whereas the second rain sample collected in the Algerian Basin (Rain FAST) was a Saharan dust wet deposition event. Even in the remote Med Sea, all background TM inputs presented an anthropogenic signature, except for Fe, Mn and Ti. The concentrations of TMs in the two rain samples were significantly lower compared to concentrations in rains collected at coastal sites reported in the literature, due to the decrease in anthropogenic emissions during the preceding decades. The atmospheric TM inputs were mainly dissolved forms, even in dusty Rain FAST. The TM stocks in the mixed layer (ML, 0-20 m) at the FAST station before and after the event showed that the atmospheric inputs were a significant supply of particulate TMs and dissolved Fe and Co for surface seawater. Even if the wet deposition delivers TMs mainly in soluble form, the post-deposition aerosol dissolution could to be a key additional pathway in the supply of dissolved TMs. At the scale of the western and central Mediterranean, the atmospheric inputs were of the same order of magnitude as ML stocks for dissolved Fe, Co and Zn, highlighting the role of the atmosphere in their Published by Copernicus Publications on behalf of the European Geosciences Union. 2310 K. Desboeufs et al.: Wet deposition in the remote western and central Mediterranean biogeochemical cycles in the stratified Med Sea. In case of intense dust-rich wet deposition events, the role of atmospheric inputs as an external source was extended to dissolved Co, Fe, Mn, Pb and Zn. Our results suggest that the wet deposition constitutes only a source of some of dissolved TMs for Med Sea surface waters. The contribution of dry deposition to the atmospheric TM inputs needs to be investigated
The impact of termites on soil sheeting properties is better explained by environmental factors than by their feeding and building strategies
No full textInternational audienceTermites are key soil bioturbators in tropical ecosystems. Apart from mound nests constructed by some advanced lineages, most of the species use their faeces, oral secretions, debris, or soil aggregates to protect themselves from predators and desiccation when they go out to forage. Although this soil ‘sheeting’ is considered to play a key role in soil functioning, the properties of this termite-made material has been poorly studied. The few available data showed that sheeting properties are highly variable with positive, neutral or negative impacts on soil C and clay content, and consequently on soil aggregate stability. Therefore, the objective of this study was to determine the factors controlling the physical (particle size fractions and structural stability) and chemical (pH, electrical conductivity and carbon content) properties of soil sheeting produced by termite species encompassing all feeding and building categories using a dataset representative of an important diversity of biotopes coming from 21 countries from all continents colonized by termites. We showed that sheeting properties were explained by the properties of their environment, and especially by those of the bulk soil (linear relationships), followed in a lesser extent by the mean annual precipitation and biotope. Classic hypotheses related to termite feeding and building strategies were not hold by our analysis. However, the distinction of termites into fungus-growing and non-fungus growing species was useful when differentiating the impact of termites on soil electrical conductivity, C content, and structural stability. The large variability observed suggests the need to redefine termite functional groups based on their impacts on soil properties using a trait-based approach from morphological, anatomical and/or physiological traits
Processes Against Tests: Defining Contextual Equivalences
No full textIn this position paper, we would like to offer and defend a template to study equivalences between programs---in the particular framework of process algebras for concurrent computation.We believe that our layered model of development will clarify the distinction that is too often left implicit between the tasks and duties of the programmer and of the tester.It will also enlighten pre-existing issues that have been running across process algebras such as the calculus of communicating systems, the -calculus---also in its distributed version---or mobile ambients.Our distinction starts by subdividing the notion of process in three conceptually separated entities, that we call \emph{process terms}, (completed) \emph{processes} and \emph{tests}, and by stressing the importance of formalizing the \emph{completion} of process terms and the \emph{instrumentation} that results from placing a (completed) processes into a test.While the role of what can be observed and the subtleties in the definitions of congruences have been intensively studied, the fact that \emph{not every term can be tested}, and that \emph{the tester should have access to a different set of tools than the programmer} is curiously left out, or at least not often formally discussed--in this respect, the theory of monitor is a counter-examples that we discuss and compare to our approach.We argue that this blind spot comes from the under-specification of contexts---environments in which comparisons occur---that play multiple distinct roles but are generally---at least, on the surface of it---given only one definition that fails to capture all of their aspects
Characteristics of thrombocytopenia, anasarca, fever, reticulin fibrosis and organomegaly syndrome: a retrospective study from a large Western cohort
No full textInternational audienceIdiopathic multicentric Castleman disease (iMCD) is a non-clonal inflammatory lymphoproliferative disorder of unknown origin. Recently, TAFRO syndrome (thrombocytopenia, anasarca, fever, reticulin fibrosis and organomegaly) emerged as a singular variant of iMCD in Asia and was associated with a severe course and a poor outcome. The present study describes the first large Western cohort of TAFRO syndrome patients (n = 25) meeting the All Japan TAFRO Syndrome Research Group diagnostic criteria. Characteristics of TAFRO patients were compared to iMCD-not otherwise specified (iMCD-NOS) patients used as a control group (n = 43). Our results show that despite baseline characteristics in accordance with previously reported series, Western TAFRO syndrome patients do not appear to present with a worse outcome than iMCD-NOS patients. There were no significant differences between the two groups regarding treatment choice, response to rituximab (71% vs. 67%) or tocilizumab (69% vs. 91%) in TAFRO and iMCD-NOS, respectively. The two-year overall survival was above 95% in both groups. Limits of inclusion and exclusion criteria for TAFRO definition are also discussed. Our findings raise the question of the singularity of the TAFRO entity in Western countries. The data should promote further research using unsupervised models to identify markers of disease severity in Western cohorts of iMCD patients