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Relations of Society Concepts and Religions from Wikipedia Networks
No full textInternational audienceWe analyze the Google matrix of directed networks of Wikipedia articles related to eight recent Wikipedia language editions representing different cultures (English, Arabic, German, Spanish, French, Italian, Russian, Chinese). Using the reduced Google matrix algorithm, we determine relations and interactions of 23 society concepts and 17 religions represented by their respective articles for each of the eight editions. The effective Markov transitions are found to be more intense inside the two blocks of society concepts and religions while transitions between the blocks are significantly reduced. We establish five poles of influence for society concepts (Law, Society, Communism, Liberalism, Capitalism) as well as five poles for religions (Christianity, Islam, Buddhism, Hinduism, Chinese folk religion) and determine how they affect other entries. We compute inter-edition correlations for different key quantities providing a quantitative analysis of the differences or the proximity of views of the eight cultures with respect to the selected society concepts and religions
Quasi-ordinary Surface germs from the topological viewpoint
No full textMathematics Subject Classifications (2000). 14B05, 14J17, 32S15,32S45, 32S55, 57M45Let (W, p) be an analytic surface germ and let ν : (W ′ , p ′ ) → (W, p) be its normalization morphism. We can associated to (W ′ , p ′ ) and (W, p) well defined links L W ′ and LW such that the restriction νLof ν to the link L W ′ is well defined. As (W ′ , p ′ ) is a normal surface germ, p ′ is an isolated singular point and L W ′ is a three dimensional topological manifold. In [13] and [14], one can find a detailed proof that LW is a topological manifold if and only if the normalization morphism νL is a homeomorphism. When the link of (W, p) is not a topological manifold, one can find in [13] and [14] a precise description of LW and in [14] a detailed study of νL. Here we only consider quasi-ordinary surface germ such that the associated link is a topological manifold (such germs are, in particular, always irreducible). We will prove, only with topological arguments, that : 1) The link of a quasi ordinary surface germ having a bijective normalization morphism is a lens space L(n, q). 2) A normal quasi-ordinary surface germ is analytically isomorphic to a cyclic quotient surface germ. As a consequence: If the link of a quasi-ordinary surface germ is a lens space L(n, q) its normalization is a cyclic quotient surface germ. These results are classical (one can refer to Brieskorn [4] and [5]). But, our proofs are new and self contained
A Green Transportation Problem for E-commerce Deliveries
No full textInternational audienceTo get involved in the fight against climate change, e-commerce actors should reduce the environmental impact of their activities. For retailers, a key challenge to is identify the stock sources for fulfilling online orders. In this paper, our goal is to orchestrate orders while minimizing the associated environmental impact. We propose a model of Green Transportation Problem for E-commerce Deliveries (GTP-ED) which can be seen as a general case of Fixed Charge Transportation Problem. We detail how we obtain the environmental objective function and how we generate instances based on real world and realistic data, and that good quality solutions can be obtained quickly. Then, we show the relevance of our environmental objective function by comparing the results with an orchestration based on minimizing the distance traveled by the parcels, which leads to a 30% increase of environmental cost. Finally, we compare the GTP-ED with an economic approach and outline a significant tension between our environmental and economic objectives in that context
On the integration of Dantzig-Wolfe and Fenchel decompositions via directional normalizations
No full textThe strengthening of linear relaxations and bounds of mixed integer linear programs has been an active research topic for decades. Enumeration-based methods for integer programming like linear programming-based branch-and-bound exploit strong dual bounds to fathom unpromising regions of the feasible space. In this paper, we consider the strengthening of linear programs via a composite of Dantzig-Wolfe and Fenchel decompositions. We provide geometric interpretations of these two classical methods. Motivated by these geometric interpretations, we introduce a novel approach for solving Fenchel sub-problems and introduce a novel decomposition combining Dantzig-Wolfe and Fenchel decompositions in an original manner. We carry out an extensive computational campaign assessing the performance of the novel decomposition on the unsplittable flow problem. Very promising results are obtained when the new approach is compared to classical decomposition methods
Mechanical compressive forces increase PI3K output signaling in breast and pancreatic cancer cells
No full textInternational audienceMechanical stresses, including compression, arise during cancer progression. In solid cancer, especially breast and pancreatic cancers, the rapid tumor growth and the environment remodeling explain their high intensity of compressive forces. However, the sensitivity of compressed cells to targeted therapies remains poorly known. In breast and pancreatic cancer cells, pharmacological PI3K inactivation decreased cell number and induced apoptosis. These effects were accentuated when we applied 2D compression forces in mechanically responsive cells. Compression selectively induced the overexpression of PI3K isoforms and PI3K/AKT pathway activation. Furthermore, transcriptional effects of PI3K inhibition and compression converged to control the expression of an autophagy regulator, GABARAP, whose level was inversely associated with PI3K inhibitor sensitivity under compression. Compression alone blocked autophagy flux in all tested cells, whereas inactivation of basal PI3K activity restored autophagy flux only in mechanically non-responsive compressed cells. This study provides direct evidence for the role of the PI3K/AKT pathway in compression-induced mechanotransduction. PI3K inhibition promotes apoptosis or autophagy, explaining PI3K importance to control cancer cell survival under compression
PUR-GEN: A web server for automated generation of polyurethane fragment libraries
No full textInternational audienceThe biodegradation of synthetic polymers offers a promising solution for sustainable plastic recycling. Polyurethanes (PUR) stand out among these polymers due to their susceptibility to enzymatic hydrolysis. However, the intricate 3D structures formed by PUR chains present challenges for biodegradation studies, both computational and experimental. To facilitate in silico research, we introduce PUR-GEN, a web server tailored for the automated generation of PUR fragment libraries. PUR-GEN allows users to input isocyanate and alcohol structural units, facilitating the creation of combinatorial oligomer libraries enriched with conformers and compound property tables. PUR-GEN can serve as a valuable tool for designing PUR fragments to mimic PUR structure interactions with proteins, as well as characterising simplistic PUR models. To illustrate an application of the web server, we present a case study on selected four cutinases and three urethanases with experimentally confirmed PUR-degrading activity or ability to hydrolyse carbamates. The use of PUR-GEN in molecular docking of 414 generated oligomers provides an example of the pipeline for initiation of the PUR degrading enzymes discovery
Improving sisal fiber-reinforced mortar properties using marble as mineral addition and chelating agent treatments
No full textInternational audienceThis study investigates the performance of sisal fiber-reinforced mortar enhanced with marble filler. To enhance compressive strength, marble waste was introduced as a partial cement replacement in increments of 5.0 % by weight. Additionally, sisal fibers were incorporated at varying proportions of 0.5 %, 1.0 %, and 1.5 % by weight of binder, utilizing two fiber lengths (6 mm and 12 mm). Given their potential to enhance mechanical properties, sisal fibers have gained attention as reinforcement in cementitious materials. Their morphology, physical characteristics, and chemical composition were analyzed in detail. A novel treatment approach was explored to mitigate the hydrophilic nature of sisal fibers. Prior to their integration into the mortar, the fibers underwent chemical modification using chelating agents—ethylenediaminetetraacetic acid (EDTA) and ammonium hydroxide (AM). The impact of these treatments was assessed through Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The study evaluated key physical properties, including workability, water absorption, and density, alongside mechanical properties such as compressive strength, tensile strength, and shrinkage. Experimental findings revealed that chemical treatments, particularly with EDTA, altered the fiber’s morphology by increasing surface roughness and reducing hydrophilicity, as evidenced by FTIR and SEM analyses. These modifications contributed to an approximately 4 % improvement in workability, notably in EDTA F-M (1 %) mortars. Furthermore, flexural tensile strength tests at 28 and 90 days demonstrated an increase of 22–23 % for EDTA-treated mortars. The inclusion of EDTA-treated fibers also led to a 13 % reduction in total shrinkage. Thermogravimetric analysis (TGA) confirmed that the EDTA-treated fibers enhanced cement hydration, leading to the formation of greater amounts of hydration products such as calcium silicate hydrate (C-S-H) and ettringite compared to untreated fibers. Overall, the findings affirm that sisal fibers can effectively reinforce mortar, and chemical treatment with EDTA significantly improves both physical and mechanical properties. This approach presents a viable strategy for developing sustainable and high-performance cementitious composites in construction
Intraluminal pressure triggers a rapid and persistent reinforcement of endothelial barriers
No full textInternational audienceIn response to mechanical cues, endothelial cells elicit highly sensitive cellular response pathways that contribute to the regulation of the physiology and disorders of the vascular system. However, it remains relatively unexplored how endothelial tissues process and integrate the intraluminal pressure, and in turn regulate the permeation flow across the vessel wall. Leveraging a tissue engineering approach to create microvessels (MVs), we measured real-time permeation flow induced by intraluminal pressures ranging from 0.1 to 2.0 kPa. Our findings reveal that mechanically stimulated MVs strengthen their barrier function within seconds of exposure to pressures below 1 kPa, with this enhanced barrier function persisting for 30 minutes. We demonstrate that this barrier reinforcement is linked to the closure of paracellular gaps. Additionally, we observe that it is associated with, and depends on, actin cytoskeleton reorganization, including the accumulation of stress fibers near intercellular junctions and the broadening of adherence junction protein localization. These findings provide insights into the ability of endothelial tissues to regulate interstitial fluid flow in response to sudden increases in blood pressure
: PFAS pollution: current state of knowledge and social issues
No full textPer- and polyfluoroalkyl substances, now well known to the public by the acronym PFAS, or their qualifier of “eternal pollutants”, encompass a wide range of molecules with unique properties. Their persistence and the mobility of some of them, combined with decades of widespread use in industrial processes, fire-fighting foams and consumer products, have led to their presence in all environments, and their accumulation in the human body and in organisms within food chains. Today, PFAS regularly make the headlines, both in the general and specialized press, due to their potential or proven effects on health. This media attention to the contamination of the environment and the impregnation of human populations is raising societal awareness and leading to changes in standards and regulations. In France, a law has just been passed, aimed at banning these compounds in a limited number of products and introducing a tax for the industries responsible for the discharges. In this context, the present report aims to sort out the proven scientific elements from those that are not established to draw up a solid inventory of the scientific knowledge available on these molecules. By means of hearings with undisputed experts in the fields of ecotoxicology, epidemiology, environmental chemistry and analytical chemistry, and an in-depth study of the available scientific literature, the French Academy of Sciences provides its analysis here and makes several recommendations. This report highlights the unprecedented complexity of PFAS pollution, which, at least in some respects, exceeds the major episodes of past environmental pollution (particularly hydrocarbons and heavy metals). Unlike the latter, PFAS pollution appears to be extremely diffuse and difficult to reverse, as there is no realistic large-scale remediation to date. Furthermore, some uses of PFAS are still not substitutable and the energy transition depends on them. In view of the health and environmental issues at stake, significant research efforts are needed to better understand the effects of these molecules, which are extremely diverse and have a wide range of properties. It is essential to identify substitute solutions and develop effective remediation methods. Pending these advances, it is imperative to ensure precise monitoring of the presence and future of PFAS. Their release into the environment must be completely prohibited. This line of thinking has led the Academy of Sciences to emphasize the importance of a broader approach to chemical exposure. This report is thus a first step towards an in-depth study of the “chemical exposome”, which will be the subject of a specific work aimed at the public and decision-makers.Les substances per- et polyfluoroalkylées, désormais bien connues du grand public sous l’acronyme anglais PFAS, ou leur qualificatif de « polluants éternels », regroupent un large éventail de molécules aux propriétés uniques. Leur persistance et la mobilité de certaines d’entre elles, combinées à desdécennies d'utilisation généralisée dans les processus industriels, les mousses anti-incendie et les produits de consommation, ont entraîné leur présence dans tous les milieux, et leur accumulation dans le corps humain et dans les organismes au sein des chaînes alimentaires.Aujourd’hui, les PFAS font régulièrement la une, tant dans la presse généraliste que spécialisée, en raison de leurs effets potentiels ou avérés sur la santé. Cette attention médiatique de la contamination des milieux et de l’imprégnation des populations humaines permet une prise deconscience sociétale et une évolution des normes et des réglementations. En France, une loi vient d’être adoptée, visant à interdire ces composés dans un nombre limité de produits et à instaurer une redevance pour les industriels responsables des rejets.Dans ce contexte, le présent rapport vise à faire le tri entre les éléments scientifiques avérés et ceux non établis afin de dresser un état des lieux solide sur les connaissances scientifiques disponibles sur ces molécules. Au moyen de l’audition d’experts incontestés des domaines de l’écotoxicologie,l’épidémiologie, la chimie de l’environnement et la chimie analytique, et d’une étude poussée de la bibliographie scientifique disponible, l’Académie des sciences fournit ici son analyse et énonce plusieurs recommandations. Ce rapport souligne la complexité inédite de la pollution aux PFAS, qui dépasse, au moins sous certains aspects, les grands épisodes de pollution environnementale passée (notamment hydrocarbures, métaux lourds). Contrairement à ces derniers, la pollution aux PFAS apparaît commeextrêmement diffuse et difficilement réversible, faute de remédiation réaliste à grande échelle à ce jour. Par ailleurs, certains usages des PFAS restent encore non substituables et, en particulier, la transition énergétique en dépend.Face aux enjeux sanitaires et environnementaux, des efforts conséquents de recherche sont nécessaires pour mieux comprendre les effets de ces molécules, dont la diversité est considérable et les propriétés très variées. Il est essentiel d’identifier des solutions de substitution et de développerdes méthodes de remédiation efficaces. En attendant ces avancées, il est impératif d’assurer un suivi précis de la présence et du devenir des PFAS. Leur émission dans l’environnement doit être totalement interdite.Cette réflexion conduit l’Académie des sciences à souligner l’importance d’une approche plus large des expositions chimiques. Ce rapport constitue ainsi une première étape vers une étude approfondie de « l’exposome chimique », qui fera l’objet d’un travail spécifique à destination du grand public etdes décideur
Contrôle de la proportion de fausses découvertes dans des modèles linéaires massivement univariés à l'aide du bootstrap résiduel
No full textInternational audienceIn this article we develop a method for performing post hoc inference of the False Discovery Proportion (FDP) over multiple contrasts of interest in the mass-univariate linear model. To do so we use the residual bootstrap to simulate from the distribution of the null contrasts. We combine the bootstrap with the post hoc inference bounds of Blanchard et al (2020) and prove that doing so provides simultaneous asymptotic control of the FDP over all subsets of hypotheses. We demonstrate, via simulations, that our approach provides simultaneous control of the FDP over all subsets and is typically more powerful than existing, state of the art, parametric methods. We illustrate our approach on functional Magnetic Resonance Imaging data from the Human Connectome project and on a transcriptomic dataset of chronic obstructive pulmonary disease.Dans cet article, nous développons une méthode permettant de réaliser une inférence post hoc sur la Proportion de Fausse Découverte (False Discovery Proportion, FDP) pour plusieurs contrastes d'intérêt dans le cadre du modèle linéaire massivement univarié. Pour ce faire, nous utilisons le bootstrap des résidus afin d'échantillonner dans la distribution des contrastes sous l'hypothèse nulle. Nous combinons cette approche par bootstrap avec les bornes d'inférence post hoc proposées par Blanchard et al. (2020) et démontrons que cette combinaison permet d'assurer un contrôle asymptotique simultané du FDP sur tous les sous-ensembles d'hypothèses. Nous montrons, à travers des simulations, que notre approche garantit ce contrôle simultané du FDP tout en étant généralement plus puissante que les méthodes paramétriques de l'état de l'art. Nous illustrons notre approche à l'aide de données d'imagerie par résonance magnétique fonctionnelle issues du Human Connectome Project et d'un jeu de données transcriptomiques sur la bronchopneumopathie chronique obstructive