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Exploring Medtech Innovation Ecosystems: A Dynamic Capabilities Approach
No full textInternational audienceIntroduced by Moore (1993) as a way to depict a business environment in which actors both collaborate and compete to create value that individual organisations could not produce otherwise, the ecosystem concept has since then gained importance in the strategic management literature. Recently, scholars have turned their attention towards orchestrating activities, which are necessary for artificial ecosystems to develop and evolve over time (Autio, 2021; Chen et al., 2019; Yaghmaie & Vanhaverbeke, 2019). Some of these activities, performed by actors called “orchestrators”, were identified by scholars (Äyväri & Spilling, 2020; Lingens et al., 2021; Roijakkers et al., 2013). However, the capabilities necessary for orchestrators to carried out their activities remain understudied. Previous research has shown the relevance of dynamic capabilities in the context of ecosystems to stimulate value creation and ecosystem renewal (Heaton et al., 2019; Helfat & Raubitschek, 2018; Linde et al., 2021). Following this stream of research, this paper draws on the dynamic capability framework to better understand ecosystem orchestration activities and determine how the study of heterogeneous ecosystems enrich the literature on dynamic capabilities in ecosystems. A single-case study of Cowork’HIT, one of the central actors in the Handicap Innovation Territoire (HIT) innovation ecosystems in Bretagne, France, helped us understand ecosystem orchestrating activities and the associated capabilities. This research contributes to the nascent literature on dynamic capabilities in ecosystems and can help policymakers to foster the emergence of orchestrators and regulate ecosystems over time
Objective diagnosis of internal nasal valve collapse by four‐phase rhinomanometry
No full textInternational audienceBackground: Internal valve collapse is a frequent cause of nasal obstruction but remains poorly understood and is sometimes treated inappropriately as a result. No functional or imaging test for the condition has been validated and the reference diagnostic technique is physical examination. The objective of this study was to evaluate the potential of four-phase rhinomanometry as a diagnostic test for internal valve collapse.Methods: In a case–control diagnostic accuracy study, the nostrils of adult patients consulting for chronic nasal obstruction were classified as “collapsed” or “non-collapsed” based on clinical findings. Four-phase rhinomanometry was performed in all patients. The area defined by the path of the flow/pressure curve in the two phases of inspiration (the “inspiratory loop area” or “hysteresis loop area”) was calculated for both nasal cavities and the threshold value with the highest Youden index was identified.Results: Sixty-six patients (132 nostrils) were included with 72 nostrils classified as collapsed and 60 as non-collapsed. Before nasal decongestion, the inspiratory loop area with the highest Youden index was 17.3 Pa L s−1 and the corresponding sensitivity and specificity were 88.3% (95% confidence interval, 80.0–95.0%) and 89.9% (82.6–95.7%), respectively.Conclusions: In these patients, a cutoff inspiratory loop area in four-phase rhinomanometry data reproduced clinical diagnoses of internal valve collapse with high sensitivity and specificity. This method may offer a firmer basis for treatment indications than subjective physical examinations
Asset pricing models with measurement error problems: A new framework with Compact Genetic Algorithms
No full textInternational audienceWe implement a new framework to mitigate the errors-in-variables (EIV) problem in the estimation of asset pricing models. Considering an international data of portfolio stock returns from 1990 to 2021 widely used in empirical studies, we highlight the importance of the estimation method in time-series regressions. We compare the traditional Ordinary-Least Squares (OLS) method to an alternative estimator based on a Compact Genetic Algorithm (CGA) in the case of the CAPM, three-, and five-factor models. Based on intercepts, betas, adjusted R2 , and the Gibbons, Ross and Shanken (1989) test, we find that the CGA-based method outperforms overall the OLS for the three asset pricing models. In particular, we obtain less statistically significant intercepts, smoother R2 across different portfolios and lower GRS test statistics. Specifically, in line with Roll's critique (1977) on the unobservability of the market portfolio, we reduce the attenuation bias in market risk premium estimates. Moreover, our results are robust to alternative methods such as Instrumental Variables estimated with Generalized-Method of Moments (GMM). Our findings have several empirical and managerial implications related to the estimation of asset pricing models as well as their interpretation as a popular tool in terms of corporate financial decision-making
Les associations de droit privé et l'application de la directive 2014/24/UE du 26 février 2014 – Précisions sur la notion d'organisme de droit public
No full textInternational audience(CJUE, 3 févr. 2021, aff. C-155/19 et C-156/19, FIGC et Consorzio Ge.Se.Av., notion d'organisme de droit public : appréciation des conditions tenant à la prise à charge d'un besoin d'intérêt général ayant un caractère autre qu'industriel et commercial et à la dépendance à l'égard d'un pouvoir adjudicateur
Aortic arch anatomy characterization from MRA: A CNN-based segmentation approach
No full textInternational audienceNeurovascular pathologies are often treated with the help of imaging to guide catheters inside arteries.However, positioning a micro-catheter into the aortic arch and threading it through blood vessels for embolization, mechanical thrombectomy or stenting is a challenging task.Indeed, adverse aortic arch anatomies are frequently encountered, especially when the aortic arch is dilated, or the supra-aortic branches are elongated and tortuous.In this article, we propose a pipeline using convolutional neural networks for the segmentation of the aortic arch from magnetic resonance images for further anatomy classification purpose.This pipeline is composed of two successive modules, dedicated to the localization and the accurate segmentation of the aortic arch and the origin of supra-aortic branches, respectively.These segmentations are then used to generate 3D models from which the anatomy and the type of the aortic arches can be characterized.A quantitative evaluation of this approach, carried out on various U-Net architectures and different optimizers, leads to satisfactory segmentation results, then allowing a reliable characterization
In-phase millennial-scale glacier changes in the tropics and North Atlantic regions during the Holocene
No full textInternational audienceBased on new and published cosmic-ray exposure chronologies, we show that glacier extent in the tropical Andes and the north Atlantic regions (TANAR) varied in-phase on millennial timescales during the Holocene, distinct from other regions. Glaciers experienced an early Holocene maximum extent, followed by a strong mid-Holocene retreat and a re-advance in the late Holocene. We further explore the potential forcing of TANAR glacier variations using transient climate simulations. Since the Atlantic Meridional Overturning Circulation (AMOC) evolution is poorly represented in these transient simulations, we develop a semi-empirical model to estimate the "AMOC-corrected" temperature and precipitation footprint at regional scales. We show that variations in the AMOC strength during the Holocene are consistent with the observed glacier changes. Our findings highlight the need to better constrain past AMOC behavior, as it may be an important driver of TANAR glacier variations during the Holocene, superimposed on other forcing mechanisms
Quantification of Microplastics by Pyrolysis Coupled with Gas Chromatography and Mass Spectrometry in Sediments: Challenges and Implications
No full textPyrolysis-GC/MS is increasingly used to quantify microplastics (MP) in environmental samples. In general, prior to analysis, purification steps are carried out to reduce the environmental matrix in sediment samples. The conventionally used protocol of density separation followed by digestion of organic matter does not allow for complete isolation of MP from the associated organic and mineral matter. Among the pyrolysis products used as indicator compounds for plastic polymers, some may originate from other substances present in the environmental samples. In this paper, the indicator compounds are reviewed for the most common polymers: PE, PP, PS, PET and PVC and selected taking into account potential interactions with substances present in environmental matrices. Even after a purification step, a residual mineral fraction remains in a sediment sample, including matrix effects. This effect may be positive or negative, depending on the investigated polymer and is thus important to consider when using Pyr-GC/MS for the quantification of MP in sediment samples. It also shows that no external calibration can be used to reliably quantify MP in such samples and that the use of internal standards is compulsory
Online data sharing with virtual social interactions favor scientific and educational successes in a biodiversity citizen science project
No full textInternational audienceGiven the diversity of biodiversity citizen science projects' design and objectives, a major challenge is to better understand the factors influencing their successes. We study an online communication space where participants to a participative biodiversity monitoring program share their data and freely interact. A quantitative analysis of the comments' distribution among participants reveals the multiplicity of epistemic and social roles they endorse: helping collective identification of plants and insects, moderating the respect of the scientific protocol, or maintaining community's life. By building a typology of these comments, we show how this space of discussion favors exchanges and reflections about esthetical, interpersonal, biological and methodological aspects. We argue that the existence of such spaces favors all together the production of high-quality data, science learning, and individual commitment towards environmental issues. Maybe more importantly, they allow citizens to build and strengthen collective epistemic and affective relationships with scienc
Adoptez l'esprit Proofmaking: Dépassez l'incertitude, innovez et propulsez vos projets
No full textInternational audienceCe livre traite des méthodes d’innovation et d’expérimentation. Partant du constat que les organisations sont le premier lieu de mort des innovations, l’ouvrage propose une approche dynamique et intégrative pour créer des « preuves » de toutes sortes et à tout moment d’un processus d’innovation pour tester et faire mûrir des hypothèses de transformation. Après avoir fourni les bases conceptuelles de la notion de preuve en innovation, le livre développe 12 études de cas réels (inédites) et 15 fiches pratiques
New cosmogenic nuclide constraints on Late Glacial and Holocene glacier fluctuations in the sub-Antarctic Indian Ocean (Kerguelen Islands, 49°S)
No full textInternational audienceCosmogenic nuclide dating of glacial landforms on the Kerguelen Archipelago (49°S, 69°E) gives the opportunity to study multi-millennial glacier fluctuations within the sub-Antarctic sector of the Indian Ocean. We here dated such geomorphic features to provide time constraints over the last 17,000 years using in situ-produced 36Cl in three glacial valleys: Val Travers valley, Ampere Glacier valley and Arago Glacier valley. For the first time, a combination of in situ-produced 36Cl and 10Be dating and 26Al/10Be ratios analysis was performed in the quartz-bearing syenite boulders of the Arago Glacier site. In addition, a Bayesian approach was computed to obtain a better constraint on moraine dating. Glacial advances occurred during the Late Glacial at 16.0 ± 1.9 ka and at 12.9 ± 1.7 ka in Val Travers, and at 13.6 ± 1.8 ka in Arago Glacier valley, probably linked to the Heinrich Stadial 1 and/or Antarctic Cold Reversal events, respectively. This suggests that all glaciers at this latitude were broadly sensitive to the large-scale climatic signal of the Antarctic Cold Reversal. So far, no Early nor Mid-Holocene moraines have been found in the glacial valleys on Kerguelen, indicating that the glaciers had probably receded significantly during these periods. This is in agreement with previously determined 14C ages from peat bogs, which suggest extensive deglaciation during several millennia of the Holocene period. Samples from glacially-polished bedrock surfaces (ranging from ~4.4 ka to ~14 ka) at Ampere Glacier site also suggest that this valley was ice free for several millennia during the Holocene. Finally, glaciers seem to have re-advanced only during the Late Holocene, especially within the last millennium, at ~1 ka, ~430 yr and ~300 yr. A comparison of this new dataset with the available 10Be ages from other southern mid latitude regions during the Holocene allows the identification of three different glacier evolution patterns. We suspect that variations of Kerguelen glaciers, which are located in the Southern Indian Ocean, were controlled by the combined effects of sea surface temperature related to the variations of the Antarctic Polar Front and fluctuations of precipitation related to long-term variations of the Southern Annular Mode