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Optimization of Aqueous Extraction of Polyphenols from Cuminum cyminum Seeds Using Response Surface Methodology and Assessment of Biological Activity
No full textInternational audience(1) Background: Cumin seeds, extracted from the plant Cuminum cyminum, are abundant in phenolic compounds and have been extensively researched for their chemical makeup and biological effects. The objective of this research is to enhance the water extraction of polyphenols through the water bath (WB) technique and to evaluate the antiradical, antibacterial, and anticancer effects of the extract. (2) Methods: Response Surface Methodology was used to find the best parameters to extract polyphenols. Three experimental parameters, time, temperature, and solid-liquid ratio, were tested. The disc diffusion method has been used to determine the antimicrobial activities against Salmonella Typhimurium, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, and Candida albicans. The antiradical activity was performed using the DPPH method, while total phenolic content was performed using Folin–Ciocalteu. High-Performance Liquid Chromatography (HPLC) was conducted to analyze the phytochemical profile of WB extracts. The anticancer activity of the lyophilized extract was assessed against three cancer cell lines (colon (HT29), lung (A549), and breast (MCF7) cancer cell lines).; (3) Results: The optimal conditions for water extraction were 130 min at 72 °C. The total phenolic compounds yield (14.7 mg GAE/g DM) and antioxidant activity (0.52 mg trolox eq./mL) were obtained using a 1:40 solid–liquid ratio. The primary polyphenols identified were the flavonoids rutin (0.1 ppm) and ellagic acid (3.78 ppm). The extract had no antibacterial or antifungal activities against the microorganisms tested. The extract showed anticancer activity of about 98% against MCF7 (breast cancer cell line), about 81% against HT29 (colon cancer cell line), and 85% against A549 (lung cancer cell line) at high doses. (4) Conclusions: Extraction time and a high solid–liquid ratio had a positive impact on polyphenol recovery and in maintaining their quantity and quality. Furthermore, the optimal aqueous extract exhibited strong antiradical activity reflected by the inhibition of free radicals in addition to a significant specificity against the tested cancer cell lines
Rhamnolipids and fengycins interact differently with biomimetic lipid membrane models of Botrytis cinerea and Sclerotinia sclerotiorum: Lipidomics profiles and in silico studies
No full textInternational audienceRhamnolipids (RLs) and Fengycins (FGs) are biosurfactants with very promising antifungal properties proposed to reduce the use of synthetic pesticides in crops. They are amphiphilic molecules, both known to target the plasma membrane. They act differently on Botrytis cinerea and Sclerotinia sclerotiorum, two close Sclerotiniaceae phytopathogenic fungi. RLs are more efficient at permeabilizing S. sclerotiorum, and FGs are more efficient at permeabilizing B. cinerea mycelial cells. To study the link between the lipid membrane composition and the activity of RLs and FGs, we analyzed the lipid profiles of B. cinerea and S. sclerotiorum. We determined that unsaturated or saturated C18 and saturated C16 fatty acids are predominant in both fungi. We also showed that phosphatidylethanolamine (PE), phosphatidic acid (PA), and phosphatidylcholine (PC) are the main phospholipids (in this order) in both fungi, with more PA and less PC in S. sclerotiorum. The results were used to build biomimetic lipid membrane models of B. cinerea and S. sclerotiorum for all-atom molecular dynamic simulations and solid-state NMR experiments to more deeply study the interactions between RLs or FGs with different compositions of lipid bilayers. Distinctive effects are exerted by both compounds. RLs completely insert in all the studied model membranes with a fluidification effect. FGs tend to form aggregates out of the bilayer and insert individually more easily into the models representative of B. cinerea than those of S. sclerotiorum, with a higher fluidification effect. These results provide new insights into the lipid composition of closely related fungi and its impact on the mode of action of very promising membranotropic antifungal molecules for agricultural applications
A novel methodology to assess optical profilometer stability to discriminate surface roughness
No full textInternational audienceA new method is proposed to investigate the measurement variation of instruments and their ability to discriminate two TA6V surfaces obtained by grinding with SiC grit papers (80 and 120). Three optical measurement technologies included into a single apparatus, namely Confocal Microscopy (CM), Focus Variation (FV) and Coherence Scanning Interferometry (CSI), were used to measure both ground surfaces according to a specific experimental protocol (MorphoMeca Monitoring) based on measurement iterations and repetitions. From the measurements, four indices were built from the Sa roughness parameter to assess the Quality (ratio of the topographical variability over the measurement noise), the Drift (related to surface fluctuations) and the Stability (estimation of the temporal drift using a second order autoregressive model) of the three measurement technologies (modes), as well as their Relevance (computed from an analysis of variance) to discriminate ground surfaces with close roughness. For these investigated surfaces, it was especially highlighted that the Quality Index is four times higher for the CSI mode than for the FV and CM modes. All the used measurement modes experienced small drifting (Drift Index) during the measurements. The CSI mode was slightly more sensitive to drift than the FV and CM modes. The Stability Index indicated that there was no memory effect between two acquisitions for each measurement mode, i.e., the temporal drift did not depend on the measurement mode. Moreover, the three measurement modes are able to discriminate the two ground surfaces with the same accuracy through the Sa parameter. However, the Sa values may vary depending on the measurement modes, and it was finally shown that the Sa parameter is minimized by 0.03 μm for the FV mode compared with the CSI mode, due to its smoothing effect
Exploring the potential of chitin and chitosan extracted from shrimp shell waste in enhancing urea-formaldehyde wood adhesives
No full textInternational audienceTea, one of the most popular beverages worldwide, generates a substantial amount of spent leaves, often directly discarded although they may still contain valuable compounds. This study aims to optimize the extraction of polyphenols from spent black tea (SBT) and spent green tea (SGT) leaves while also exploring their antioxidant and antibacterial properties. Response surface methodology was utilized to determine the optimal experimental conditions for extracting polyphenols from SBT and SGT. The total phenolic content (TPC) was quantified using the Folin–Ciocalteu method, while antioxidant activity was evaluated through the DPPH assay. Antibacterial activity was assessed using the disk diffusion method. Additionally, high-performance liquid chromatography (HPLC) was employed to analyze the phytochemical profiles of the SBT and SGT extracts. Optimal extraction for SBT achieved 404 mg GAE/g DM TPC and 51.5% DPPH inhibition at 93.64 °C, 79.9 min, and 59.4% ethanol–water. For SGT, conditions of 93.63 °C, 81.7 min, and 53.2% ethanol–water yielded 452 mg GAE/g DM TPC and 78.3% DPPH inhibition. Both tea extracts exhibited antibacterial activity against Gram-positive bacteria, with SGT showing greater efficacy against S. aureus and slightly better inhibition of B. subtilis compared to SBT. No activity was observed against the Gram-negative bacteria E. coli and S. typhimurium. HPLC analysis revealed hydroxybenzoic acid as the main phenolic compound in SBT (360.7 mg/L), while rutin was predominant in SGT (42.73 mg/L). The optimized phenolic-rich extracts of SBT and SGT demonstrated promising antioxidant and antibacterial potential, making them strong candidates for use as natural health boosters in food products
Développement d'un matériau multiphasique à gradient continu pour l'ingénierie tissulaire des jonctions ostéotendineuses et myotendineuses
No full textDie Sehne verbindet den Knochen und den Muskel und ermöglicht so die Bewegung. Leider sind Sehnenverletzungen sehr häufig und die derzeitigen Behandlungsmöglichkeiten sind unbefriedigend. Dies lässt sich durch die geringe Regenerationsfähigkeit der Sehne im Gegensatz zu Knochen und Muskeln erklären. Ein innovatives Konzept besteht darin, ein Sehnentransplantat mit Knochen und Muskel an beiden Enden zu entwickeln, um die vollständige Insertion beim Patienten zu fördern. Die Sehnenverbindungen besitzen eine einzigartige Architektur, die berücksichtigt werden muss. Die Literaturanalyse von nativem Gewebe und additiven Herstellungstechniken legt nahe, dass eine lokalisierte Zelldifferenzierung durch topografische und mechanische Faktoren anstelle der eher biochemischen Elemente erreicht werden könnte, die eine gemeinsame Kultivierung von Zellen in einem einzigen Medium ermöglichen. Unsere erste Hypothese ist, dass die osteogene Differenzierung durch die Struktur des Materials induziert werden kann. Elektrogesponnene Polyprolactonfasern wurden auf mikrogefertigte Waben aufgetragen, um dicke Strukturen zu erzeugen, die nativen Osteonen nachempfunden sind. Auf diesen Materialien gezüchtet, zeigten C3H10-Progenitorzellen eine starke ALP-Färbung, die derjenigen auf Fasern mit Hydroxylapatit-Nanopartikeln entsprach. Anschließend untersuchten wir, ob eine einzelne Zellpopulation auf einem einzelnen mikrostrukturierten Material mit mechanischer Stimulation zur Differenzierung von Sehne und Knochen geführt werden kann. Ein neuer Elektrospinnkollektor wurde entwickelt, um ein Material herzustellen, das aus einem Gradienten besteht, der von einer Wabenstruktur bis zu ausgerichteten Fasern reicht. Die dynamische Zellkultur, die aus der Dehnung des Materials bestand, zeigte eine klare Differenzierung von C3H10 in Richtung Knochen und Sehne auf den jeweiligen Strukturen. Die nächste Herausforderung bestand darin, eine Knochen-Sehnen-Muskel-Konstruktion zu entwickeln, die zwei verschiedene Zelltypen auf einem einzigen Material verwendet, das aus drei topografischen Bereichen besteht: Waben, ausgerichtete Fasern, ausgerichtete Fasern, die durch PEG-Linien für den Muskelteil abgedeckt sind. Trotz der Bildung von Myotubes wurde die Differenzierung von Knochen und Sehne behindert, was auf eine Auswirkung der C3H10 und C2C12 Kokultur, aber auch auf die Grenzen der Verwendung von Zelllinien. Der nächste Schritt in dieser Forschung muss die Kultivierung anderer Zelltypen, wie primärer Stammzellen oder mesenchymaler Zellen anpassen, um das Knochen-Sehnen-Muskel-Kontinuum zu erreichen.Tendon links bone and muscle, making movement possible. Unfortunately, tendon injuries are very common and current treatment are not satisfying. This can be explained by the low regeneration of the tendon compared to bone and muscle. An innovative concept is to develop a tendon engineered graft with bone and muscle compatible structures at both ends so as to favor the whole insertion in the patient. Bone-tendon (enthesis) and myotendinous junctions possess unique architecture that must taken into account and reproduced. The bibliographical analysis of both native tissues and additive manufacturing techniques suggests that the localized differentiation of cells (into bone, tendon or muscle lineages) could be achieved by topographical and mechanical cues, instead of more classical biochemical ones, allowing cells co-culture in a same medium and on a unique scaffold. Our first hypothesis is that osteogenic differentiation can be induced by honeycomb-like structure, mimicking native osteons. Beads-on-string polyprolactone electrospun fibers were deposited on microfabricated honeycomb to produce thick structures. When cultured on these scaffolds, C3H10 progenitor cells exhibited high ALP staining equivalent to those observed on fibers associated to hydroxyapatite nanoparticles, confirming this hypothesis. Then, we investigated whether a unique cell population can be guided to tendon and bone’s fate on a single scaffold through specific topography and mechanical stimulation. A novel electrospinning collector was designed to manufacture a scaffold composed of gradient from honeycomb-like structure to aligned fibers. Dynamic cell culture consisting in stretching of the scaffold showed clear differentiation of C3H10 to bone and tendon fate on the honeycomb and aligned fibers structures, respectively. The next challenge was to develop a bone-tendon-muscle cell construct using two different cell types on a single scaffold composed of three topographical areas: honeycomb, aligned fibers, aligned fibers covered by PEG lines for the muscle part. To our knowledge, the process to manufacture such a multiphasic scaffold has never been described. Preliminary coculture of C3H10 (on bone and tendon areas) and C2C12 cells (on muscle area) was implemented. Myotube formation appeared to be induced, while bone and tendon differentiation were hindered, indicating an impact of the co-culture on the cell fate, but also the limits of using cell lines with a high proliferative potential. The next step in multi-interfacial tissue engineering need to adapt the culture of other cell types, such as primary or mesenchymal stem cells, as well as the dynamic conditions to achieve the bone-tendon-muscle continuum.Le tendon relie l'os et le muscle, permettant le mouvement. Malheureusement, les lésions du tendon sont très fréquentes et les traitements actuels sont insatisfaisants. Cela peut s'expliquer par la faible capacité de régénération du tendon, contrairement à l'os et au muscle. Un concept innovant consiste à développer un greffon tendineux avec de l'os et du muscle aux deux extrémités afin de favoriser l'insertion complète chez le patient. Les jonctions du tendon possèdent une architecture unique qui doit être prise en compte. L'analyse bibliographique des tissus natifs et des techniques de fabrication additive suggère que la différenciation localisée des cellules pourrait être obtenue par des facteurs topographiques et mécaniques, au lieu des éléments biochimiques plus classiques, permettant la co-culture des cellules dans un même milieu. Notre première hypothèse est que la différenciation ostéogénique peut être induite par la structure du matériau. Des fibres électrofilées de polyprolactone ont été déposées sur des nids d'abeilles microfabriqués afin de produire des structures épaisses imitant les ostéons natifs. Cultivées sur ces matériaux, les cellules progénitrices C3H10 présentent une forte coloration ALP équivalente à celle observée sur des fibres avec nanoparticules d'hydroxyapatite. Ensuite, nous avons cherché à savoir si une population cellulaire unique pouvait être guidée vers une différenciation du tendon et de l'os sur un seul matériau microstructuré avec stimulation mécanique. Un nouveau collecteur d'électrofilage a été conçu pour fabriquer un matériau composé d'un gradient allant d'une structure en nid d'abeille à des fibres alignées. La culture cellulaire dynamique consistant en l'étirement du matériau a montré une différenciation claire de C3H10 vers l'os et le tendon sur les structures respectives. Le défi suivant consistait à développer une construction os-tendon-muscle utilisant deux types de cellules différents sur un seul matériau composé de trois zones topographiques : nid d'abeille, fibres alignées, fibres alignées couvertes par des lignes de PEG pour la partie musculaire. A notre connaissance, le processus de fabrication d'un tel matériau multiphasique n'a jamais été décrit. Une coculture préliminaire de C3H10 avec l’addition des C2C12 (sur la zone musculaire) a été mise en place. Malgré la formation de myotubes, la différenciation de l’os et du tendon est entravée, ce qui indique un impact de la coculture, mais aussi les limites de l'utilisation de lignées cellulaires à fort potentiel prolifératif. La prochaine étape de cette recherche devra adapter la culture d'autres types de cellules, telles que les cellules souches primaires ou mésenchymateuses, ainsi que les conditions dynamiques pour atteindre le continuum os-tendon-muscle
Industrialization of Site Operations Planning and Management: A BIM-Based Decision Support System
No full textInternational audienceConstruction industry faces many challenges as socio-economical needs evolve and Building Information Modeling (BIM) disrupts practices. BIM processes and solutions are mainly suited for the design stage of a project and experts are currently working to bridge the gap with the construction stage. Improving on BIM practices could be done by creating a more industrialized way of handling construction operations by learning from other industrial fields. This could help to manage quality, delay, and cost more precisely, while considering new indicators (e.g.: GHG emissions). BIM could be improved by developing a construction stage specific data structure inspired by Product Lifecycle Management (PLM) systems. This requires to dynamically manage data for different stakeholders before and during the operations. This paper presents a conceptual data framework to develop a BIM-based decision support system to plan and manage construction operations. A 4D digital mock-up is gradually enriched to support construction processes studies resulting in a As Planned view of the building. Process engineering work is carried through iterative loops and supported by knowledge-based indicators. A cross-disciplinary workflow allows the use of new production methods (e.g.: off-site modular construction). An As Built view of the mock-up is concurrently created as operations advance and changes occur, feeding back the knowledge-based indicators
De la coproduction à la commonisation des biens et services publics
No full textInternational audienceThe hybridization of digital commons and public administration institutions led by bureaucratic entrepreneurs is a relatively recent phenomenon that has received limited attention in the literature. The term coined to describe this evolution is the "commonization" of digital public goods and services. We define commonization as the integration of shared property, peer production, and self-governance into public administration. To explore the democratizing potential of commonization, we conducted a qualitative study comparing two case studies in France and Spain (Barcelona). Our approach involves forty-four semi-structured interviews and online observations analyzed through the analytical framework of institutional work. Our findings highlight five factors that enhance, and two that hinder, citizen power in co-governance arrangements. In conclusion, we identify the theoretical and practical implications of commonizing digital public goods and services, providing valuable insights for practitioners and scholars, particularly in the New Public Governance paradigm
Event-based Semantic-aided Motion Segmentation
No full textInternational audienceEvent cameras are emerging visual sensors inspired by biological systems. They capture intensity changes asynchronously with a temporal precision of up to µs, in contrast to traditional frame imaging techniques running at a fixed frequency of tens of Hz. However, effectively utilizing the data generated by these sensors requires the development of new algorithms and processing. In light of event cameras' significant advantages in capturing high-speed motion, researchers have turned their attention to event-based motion segmentation. Building upon (Mitrokhin et al., 2019) framework, we propose leveraging semantic segmentation enable the end-to-end network not only to segment moving objects from background motion, but also to achieve semantic segmentation of distinct moving objects. Remarkably, these capabilities are achieved while maintaining the network's low parameter count of 2.5M. To validate the effectiveness of our approach, we conduct experiments using the EVIMO dataset and the new and more challenging EVIMO2 dataset (Burner et al., 2022). The results demonstrate improvements attained by our method, showcasing its potential in event-based multi-objects motion segmentation
Measuring the slack between lower bounds for scheduling on parallel machines
No full textInternational audienceThis paper considers the problem of scheduling independent jobs with release dates and tails on m identical machines to minimize the makespan. The three main bounds are the preemptive bound, the energetic bound and the Jackson Pseudo Preemptive bound. It is known that they are very close in practice. The aim of this paper is to provide worst case instances where the slack between them is maximal and to prove tight bounds on the slack. We show that the slack is smaller than the maximal processing time
Robust augmented energy a posteriori estimates for Lipschitz and strongly monotone elliptic problems
No full textIn this paper, we design a posteriori estimates for finite element approximations of nonlinear elliptic problems satisfying strong-monotonicity and Lipschitz-continuity properties. These estimates include, and build on, any iterative linearization method that satisfies a few clearly identified assumptions; this encompasses the Picard, Newton, and Zarantonello linearizations. The estimates give a guaranteed upper bound on an augmented energy difference (reliability with constant one), as well as a lower bound (efficiency up to a generic constant). We prove that for the Zarantonello linearization, this generic constant only depends on the space dimension, the mesh shape regularity, and possibly the approximation polynomial degree in four or more space dimensions, making the estimates robust with respect to the strength of the nonlinearity. For the other linearizations, there is only a computable dependence on the local variation of the linearization operators. We also derive similar estimates for the usual energy difference that depend locally on the nonlinearity and improve the established bound. Numerical experiments illustrate and validate the theoretical results, for both smooth and singular solutions