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International audience; This paper explores the potentialities offered by blue-green approaches to promote protection of water resources at the metropolitan scale and to contribute to structuring territorial development. An ongoing experience of regional planning and land use regulation in the Belo Horizonte Metropolitan Region (BHMR), in Brazil, is here a reference. With a population of 5.8 million inhabitants and territory of 10,000 km2, the BHMR offers a rich example of land use diversity that highlights the complexity of metropolitan territorial planning and management. In the first part of the paper, blue-green concepts are developed emphasising their role for the protection of water resources. This is followed by the methods and results of applying these concepts to the BHMR. We then evaluate whether blue-green approaches are sufficient to protect water resources and discuss the potentialities of additional tools such as the payment for environmental services with the same objectives.

International audience; Faecalibacterium prausnitzii is a commensal bacterium, ubiquitous in the gastrointestinal tracts of animals and humans. This species is a functionally important member of the microbiota and studies suggest it has an impact on the physiology and health of the host. F. prausnitzii is the only identified species in the genus Faecalibacterium, but a recent study clustered strains of this species in two different phylogroups. Here, we propose the existence of distinct species in this genus through the use of comparative genomics. Briefly, we performed analyses of 16S rRNA gene phylogeny, phylogenomics, whole genome Multi-Locus Sequence Typing (wgMLST), Average Nucleotide Identity (ANI), gene synteny, and pangenome to better elucidate the phylogenetic relationships among strains of Faecalibacterium. For this, we used 12 newly sequenced, assembled, and curated genomes of F. prausnitzii, which were isolated from feces of healthy volunteers from France and Australia, and combined these with published data from 5 strains downloaded from public databases. The phylogenetic analysis of the 16S rRNA sequences, together with the wgMLST profiles and a phylogenomic tree based on comparisons of genome similarity, all supported the clustering of Faecalibacterium strains in different genospecies. Additionally, the global analysis of gene synteny among all strains showed a highly fragmented profile, whereas the intra-cluster analyses revealed larger and more conserved collinear blocks. Finally, ANI analysis substantiated the presence of three distinct clusters—A, B, and C—composed of five, four, and four strains, respectively. The pangenome analysis of each cluster corroborated the classification of these clusters into three distinct species, each containing less variability than that found within the global pangenome of all strains. Here, we propose that comparison of pangenome subsets and their associated α values may be used as an alternative approach, together with ANI, in the in silico classification of new species. Altogether, our results provide evidence not only for the reconsideration of the phylogenetic and genomic relatedness among strains currently assigned to F. prausnitzii, but also the need for lineage (strain-based) differentiation of this taxon to better define how specific members might be associated with positive or negative host interactions.

International audience; Background: Drug ocular toxicity is a field that requires attention. Clindamycin has been injected intravitreally to treat ocular toxoplasmosis, the most common cause of eye posterior segment infection worldwide. However, little is known about the toxicity of clindamycin to ocular tissues. We have previously showed non intraocular toxicity in rabbit eyes of poly(lactic-co-glycolic acid) (PLGA) implants containing clindamycin hydrochloride (CLH) using only clinical macroscotopic observation. In this study, we investigated the in vivo biocompatibility of CLH-PLGA implants at microscotopic, cellular and molecular levels.Methods: Morphology of ARPE-19 and MIO-M1 human retinal cell lines was examined after 72 h exposure to CLH-PLGA implant. Drug delivery system was also implanted in the vitreous of rat eyes, retinal morphology was evaluated in vivo and ex vivo. Morphology of photoreceptors and inflammation was assessed using immunofluorescence and real-time PCR.Results: After 72 h incubation with CLH-PLGA implant, ARPE-19 and MIO-M1 cells preserved the actin filament network and cell morphology. Rat retinas displayed normal lamination structure at 30 days after CLH-PLGA implantation. There was no apoptotic cell and no loss in neuron cells. Cones and rods maintained their normal structure. Microglia/macrophages remained inactive. CLH-PLGA implantation did not induce gene expression of cytokines (IL-1β, TNF-α, IL-6), VEGF, and iNOS at day 30.Conclusion: These results demonstrated the safety of the implant and highlight this device as a therapeutic alternative for the treatment of ocular toxoplasmosis.

International audience; Swiss cheeses have been produced for centuries in a traditional way and their typical opening indicates the presence of propionibacteria. These last are indeed present in raw milk, their growth is favored by the specific technology of Swiss-type cheeses, and their high population in the ripened cheese is responsible for its characteristic sensory properties, including the opening and the aroma. In addition to this long history of safe use and consumption, they constitute a source of nutraceuticals. The specific propionic fermentation leads to the production of short chain fatty acids as main final obligatory products. These exert beneficial effects including nourishment of digestive epithelial cells, as well as promotion of differentiation and of apoptotic depletion of colon cancer cells. Propionibacteria also produce vitamins of the B group, which enhances the nutritional value of the food products they ferment. Some selected strains were moreover shown to produce immunomodulins, proteins able to modify the secretion of cytokines in human immune cells. These last were identified as proteinaceous components of propionibacteria surface layer. They also produce extracellular vesicles which modulate in vitro inflammation and the NFκB pathway in human intestinal epithelial cells. Accordingly, such strains modulate the immune response and mitigate inflammation. In mice, they prevent both mucositis and colitis, via such immunomodulins limiting acute inflammatory response and protecting the gut epithelial barrier. In pigs, their consumption also modulates the inflammatory response and the lymphocyte populations. Finally, clinical studies dealing with consumption of propionibacteria whey cultures suggest a beneficial role in the context of IBD. Propionibacteria strains were recently identified in the gut microbiota of healthy newborns, yet not in that of children with necrotizing enterocolitis. Indeed, propionibacteria were detected in human fecal samples, which means that propionibacteria may be traditional cheese starters or next generation probiotics. The growing knowledge of these peculiar actinobacteria, including their great strain-diversity, opens new avenues for the development of functional foods and of food supplements, in a general context of increasing incidence of ailments that include an inflammatory component. Moreover, their ability to ferment both dairy and vegetable matrices is presently investigated and the first promising advances open new perspectives for the development of functional fermented vegetable products.

International audience; Several architectures of Bulk Built-In Current Sensors (BBICS) were recently proposed to monitor transient faults induced on integrated circuits by radiation or malicious sources. This work compares for the first time all existing static BBICS architectures in terms of their sensitivities to detect transient faults. In addition, we propose a new static BBICS that presents better results of transient-fault detection sensitivity than previous sensor architectures.

International audience; This paper is concerned with a new control method for path tracking of autonomous ground vehicles. We exploit the fuzzy model-based control framework to deal with the time-varying feature of the vehicle speed and the highly uncertain behaviors of the tire-road forces involved in the nonlinear vehicle dynamics. To avoid using costly vehicle sensors for feedback control while favoring the simplest control structure for real-time implementation, a new fuzzy static output feedback (SOF) scheme is proposed. In particular, though the robust set-invariance property and Lyapunov-based arguments, the physical constraints on the steering input saturation and the vehicle state can be taken into account in the control design to improve the driving safety and comfort. The theoretical development relies on the use of fuzzy Lyapunov functions and the non-parallel distributed compensation control concept to reduce the design conservatism. Exploiting some specific convexification techniques, the control design is reformulated as an optimization problem under linear matrix inequalities with a single line search, which are efficiently solved via semidefinite programming techniques. The proposed fuzzy path tracking controller is evaluated through various dynamic driving tests conducted with high-fidelity CarSim/Matlab co-simulations. Moreover, to emphasize the advantages of the new fuzzy SOF controller, a performance comparison with the CarSim driver model is also performed.

International audience; This article presents a new approach to design static output-feedback (SOF) controllers for constrained Takagi-Sugeno fuzzy systems with nonlinear consequents. The proposed SOF fuzzy control framework is established via the absolute stability theory with appropriate sector-bounded properties of the local state and input nonlinearities. Moreover, both state and input constraints are explicitly taken into account in the control design using set-invariance arguments. Especially, we include the local sector-bounded nonlinearities of the fuzzy systems in the construction of both the nonlinear controller and the nonquadratic Lyapunov function. Within the considered local control context, the new class of nonquadratic Lyapunov functions provides an effective solution to estimate the closed-loop domain of attraction, which can be nonconvex and even disconnected. The convexification procedure is performed using specific congruence transformations in accordance with the special structures of the proposed SOF controllers and nonquadratic Lyapunov functions. Consequently, the fuzzy SOF control design can be reformulated as an optimization problem under strict linear matrix inequality constraints with a linear search parameter. Compared to existing fuzzy SOF control schemes, the new structures of the control law and the Lyapunov function are more general and offer additional degrees of freedom for the control design. Both theoretical arguments and numerical illustrations are provided to demonstrate the effectiveness of the proposed approach in reducing the design conservatism.

International audience; The M-regression estimator has recently been widely used to build spectral estimators in time series models. In this paper, we extend this approach when the data follow a periodic autoregressive moving average (PARMA) process. We introduce an estimator of the parameters based on the classical Whittle estimator. The finite sample size performances of the proposed estimator are analyzed under the scenarios of PARMA processes with and without additive outliers (AO). Under the non-contaminated scenario, our estimator and the maximum Gaussian and Whittle likelihood estimators have similar behaviors. However, in the contaminated case, the two last estimators are severely biased, while the proposed estimator is robust. As a real data application, carbon monoxide (CO) concentrations are analyzed. A PARMA model is fitted and the data are forecasted with the model.

Backgrounds Infant-directed speech (IDS) is part of an interactive loop that plays an important role in infants’ cognitive and social development. The use of IDS is universal and is composed of linguistic and emotional components. However, whether the emotional component has similar acoustics characteristics has not been studied automatically. Methods We performed a cross-cultural study using automatic social signal processing techniques (SSP) to compare IDS across languages. Our speech corpus consisted of audio-recorded vocalizations from parents during interactions with their infant between the ages of 4 and 18 months. It included 6 databases of five languages: English, French, Hebrew (two databases: mothers/fathers), Italian, and Brazilian Portuguese. We used an automatic classifier that exploits the acoustic characteristics of speech and machine learning methods (Support Vector Machines, SVM) to distinguish emotional IDS and non-emotional IDS. Results Automated classification of emotional IDS was possible for all languages and speakers (father and mother). The uni-language condition (classifier trained and tested in the same language) produced moderate to excellent classification results, all of which were significantly different from chance (P Conclusion The automated classification of emotional and non-emotional components of IDS is possible based on the acoustic characteristics regardless of the language. The results found in the cross-over condition support the hypothesis that the emotional component shares similar acoustic characteristics across languages.

International audience; One irreversible consequence of acidic pH for roots is cell death. Growing evidence suggests the role of hormones and cell wall-related enzymes in response to acidic pH that could possibly avoid cell mortality. Here, we have investigated the role of ethylene and class III peroxidases (CIII Prxs) activity on sensitivity to further low pH treatment. Seedlings of Arabidopsis thaliana were pretreated with ethylene, at various concentrations for various times, and then exposed to low pH. In contrast to non-treated roots, roots pretreated with ethylene for 3 h became tolerant to subsequent low pH, with negligible cell mortality in meristematic (MZ), transition (TZ), and early elongation (EZ) zones. This effect of ethylene was time dependent since it was achieved only when seedlings were pre-incubated with ethylene for at least 3 h. This tolerance induced by ethylene was not observed in the gain-of-function mutation etr1-1 (insensitive to ethylene 1–1). Besides, it was prevented by salicylhydroxamic acid (SHAM) which is an inhibitor of CIII Prxs activity. In late EZ, the decrease in cell expansion due to low pH was dependent on both ethylene signaling and a SHAM-sensitive process. The responses mediated by ethylene signaling might involve CIII Prxs-dependent cell wall modifications, leading to tolerance to low pH and arrest in cell expansion during stress.

PurposeThe study aims to highlight and reflect on resistance to Brazil's illiberal accelerationist politics highlighting alternative possibilities based on affects and forms of relatedness.Design/methodology/approachDrawing on the case of public universities and the arts in today's Brazil, the authors point out a tragedy of resistance (when opposing change fuels its acceleration) and explore a strategy of lines of flight and becomings in the light of Deleuze and Guattari's perspective on acceleration.FindingsAlongside an oppositional and reactive resistance, that is caught in a tragedy of resistance, the authors explore an alternative strategy that protects a plurality of life forms and forces and their becoming. This strategy differs from most critiques of accelerationism.Originality/valueThis strategy of resistance seems more faithful to Deleuze than the accelerationist strategies that claim to be inspired by him. The authors suggest another reading of the often quoted passage by Deleuze and Guattari. While Deleuze and Guattari favor continuous deterritorializations of the flows of desire, accelerationism reterritorializes these flows towards a (often) undesirable future.

Predicting how humans move within space and time is a central topic in many scientific domains such as epidemic propagation, urban planning, and ride-sharing. However, current studies neglect individuals' preferences to explore and discover new places. Yet, neglecting novelty-seeking activities at first glance appears to be inconsequential on the ability to understand and predict individuals' trajectories. In this work, we claim and show the opposite: exploration moments strongly impact mobility understanding and anticipation. We start by proposing a new approach to identifying moments of novelty-seeking. Based on that, we construct individuals' mobility profiles using their exploration inclinations-Scouters (i.e., extreme explorers), Routiners (i.e., extreme returners), and Regulars (i.e., an individual with no extreme behavior). Finally, we evaluate the impacts of noveltyseeking, quality of the data, and the prediction task formulation on the theoretical and practical predictability extents. The results show the validity of our profiling and highlight the obstructive impacts of novelty-seeking activities on the predictability of human trajectories, in particular, on Scouters.

International audience; A major limiting factor for prediction algorithms is the forecast of new or never before-visited locations. Conventional personal models utterly relying on personal location data perform poorly when it comes to discoveries of new regions. The reason is explained by the prediction relying only on previously visited/seen (or known) locations. As a side effect, locations that were never visited before (or explorations) by a user cause disturbance to known location's prediction. Besides, such explorations cannot be accurately predicted. We claim the tackling of such limitation first requires identifying the purpose of the next probable movement. In this context, we propose a novel framework for adjusting prediction resolution when probable explorations are going to happen. As recently demonstrated [1, 2], there exist regularities in returning and exploring visits. Moreover, the geographical occurrences of explorations are far from being random in a coarser-grained spatial resolution. Exploiting these properties, instead of directly predicting a user's next location, we design a two-step predictive framework. First, we infer an individual's next type of transition: (i) a return, i.e., a visit to a previously known location, or (ii) an exploration, i.e., a discovery of a new place. Next, we predict the next location or the next coarse-grained zone depending on the inferred type of movement. We conduct extensive experiments on three real-world GPS mobility traces. The results demonstrate substantial improvements in the accuracy of prediction by dint of fruitfully forecasting coarse-grained zones used for exploration activities. To the best of our knowledge, we are the first to propose a framework solely based on personal location data to tackle the prediction of visits to new places.

International audience; In this work, an Artificial Magnetic Conductor (AMC) metasurface composed by a Sierpinski Carpet fractal unit cell is analyzed using the Generalized Boundary Conditions (GBCs). Since the fractal structure cannot be represented using analytical expressions, the detailed GBCs model is presented to analyze angular and polarization stabilities of the obtained metasurface. The angular stability of the fractal geometry is compared with the square loop and Jerusalem Cross geometries, from the stable bandwidth and frequency deviation. Finally, the computational effort and the accuracy of the proposed method is compared to conventional methods through performance parameters, thus validating GBCs as an alternative method to characterize AMCs.

International audience; Low pH stress (pH < 5.5) triggers sensitivity responses in roots such as cell death (CD) or arrest in elongation which are detrimental to the development of many plant species. The involvement of the cell wall (CW) with these sensitive responses and their spatiotemporal dynamics in the distinct root zones remains poorly understood. The spatio-temporal analysis of primary roots of Arabidopsis thaliana upon low pH (pH 4.6) revealed that the CD repeatedly started in cells of the transition zone (TZ). Then, CD dynamically moved downward to the meristematic zone (MZ) and upward to the early elongation zone (EZ). The dead cells exhibited coordinated in situ DNA fragmentation, highlighted by the deformity in the nuclei of dead cells and positive reaction for Terminal Deoxynucleotidyl Transferase-mediated dUTP Nick-End Labeling (TUNEL). This DNA fragmentation strongly suggests that the low pH-driven CD occurred through a programmed cell death (PCD) pathway. In addition, a decreased CW stiffness in TZ epidermal cells before the onset of CD suggests that low pH first triggers cell wall disturbances (CWDs) in these root cells. Disruption in CW integrity caused by incorrect cellulose deposition in cobra (cob-1) mutant enhanced CD in TZ and early EZ. Supporting this notion, an increase in calcium concentration upon low pH alleviated the CD in roots, probably due to its role in stabilization of the pectin crosslinking in CWs and likely counteracting the low pH-induced CWDs. Moreover, the CD was significantly decreased when roots were exposed to low pH under reduced CW tension, however, a sudden increase in turgor pressure and CW tension (hypoosmotic treatment) combined with low pH accelerated CD in TZ and early EZ. The CD was not observed in the wild type late EZ trichoblasts upon low pH but rather an orchestrated arrest in elongation. An increase in calcium concentration inhibited this elongation arrest upon low pH, suggesting that the onset of this response also required CWDs. Altogether, these results indicate that low pH-induced CWDs triggered sensitive responses within defined root zones. The low pH-activated PCD and an orchestrated elongation arrest occurring in different root zones suggest the occurrence of yet to be identified signaling cascades.

International audience; Given the difficulties in predicting human behavior, one may wish to establish bounds on our ability to accurately perform such predictions. In the case of mobility-related behavior, there exists a fundamental technique to estimate the predictability of an individual’s mobility, as expressed in a given dataset. Although useful in several scenarios, this technique focused on human mobility as a monolithic entity, which poses challenges to understanding different types of behavior that may be hard to predict. In this paper, we propose to study predictability in terms of two components of human mobility: routine and novelty, where routine is related to preferential returns, and novelty is related to exploration. Viewing one’s mobility in terms of these two components allows us to identify important patterns about the predictability of one’s mobility. Additionally, we argue that mobility behavior in the novelty component is hard to predict if we rely on the history of visited locations (as the predictability technique does), and therefore we here focus on analyzing what affects the predictability of one’s routine. To that end, we propose a technique that allows us to (i) quantify the effect of novelty on predictability, and (ii) gauge how much one’s routine deviates from a reference routine that is completely predictable, therefore estimating the amount of hard-to-predict behavior in one’s routine. Finally, we rely on previously proposed metrics, as well as a newly proposed one, to understand what affects the predictability of a person’s routine. Our experiments show that our metrics are able to capture most of the variability in one’s routine (adjusted $R^{2}$ R 2 of up to 84.9% and 96.0% on a GPS and CDR datasets, respectively), and that routine behavior can be largely explained by three types of patterns: (i) stationary patterns, in which a person stays in her current location for a given time period, (ii) regular visits, in which people visit a few preferred locations with occasional visits to other places, and (iii) diversity of trajectories, in which people change the order in which they visit certain locations.

International audience; Short-chain fatty acids (SCFAs) are the main metabolites produced by the gut microbiota via the fermentation of complex carbohydrates and fibers. Evidence suggests that SCFAs play a role in the control of infections through direct action both on microorganisms and on host signaling. This review summarizes the main microbicidal effects of SCFAs and discusses studies highlighting the effect of SCFAs in the virulence and viability of microorganisms. We also describe the diverse and complex modes of action of the SCFAs on the immune system in the face of infections with a specific focus on bacterial and viral respiratory infections. A growing body of evidence suggests that SCFAs protect against lung infections. Finally, we present potential strategies that may be leveraged to exploit the biological properties of SCFAs for increasing effectiveness and optimizing patient benefits.

Resistive switching (RS) devices are promising forms of non-volatile memory. However, one of the biggest challenges for RS memory applications is the device-to-device (D2D) variability, which is related to the intrinsic stochastic formation and configuration of oxygen vacancy (VO) conductive filaments (CFs). In order to reduce the D2D variability, control over the formation and configuration of oxygen vacancies is paramount. In this study, we report on the Zr doping of TaO x -based RS devices prepared by pulsed-laser deposition as an efficient means of reducing the VO formation energy and increasing the confinement of CFs, thus reducing D2D variability. Our findings were supported by XPS, spectroscopic ellipsometry and electronic transport analysis. Zr-doped films showed increased VO concentration and more localized VOs, due to the interaction with Zr. DC and pulse mode electrical characterization showed that the D2D variability was decreased by a factor of seven, the resistance window was doubled, and a more gradual and monotonic long-term potentiation/depression in pulse switching was achieved in forming-free Zr:TaO x devices, thus displaying promising performance for artificial synapse applications.

The pervasiveness of smartphones has shaped our lives, social norms, and the structure that dictates human behavior. They now directly influence how individuals demand resources or interact with network services. From this scenario, identifying key locations in cities is fundamental for the investigation of human mobility and also for the understanding of social problems. In this context, we propose the first graph-based methodology in the literature to quantify the power of Point-of-Interests (POIs) over its vicinity by means of user mobility trajectories. Different from literature, we consider the flow of people in our analysis, instead of the number of neighbor POIs or their structural locations in the city. Thus, we modeled POI’s visits using the multiflow graph model where each POI is a node and the transitions of users among POIs are a weighted direct edge. Using this multiflow graph model, we compute the attract, support, and independence powers . The attract power and support power measure how many visits a POI gathers from and disseminate over its neighborhood, respectively. Moreover, the independence power captures the capacity of a POI to receive visitors independently from other POIs. We tested our methodology on well-known university campus mobility datasets and validated on Location-Based Social Networks (LBSNs) datasets from various cities around the world. Our findings show that in university campus: (i) buildings have low support power and attract power ; (ii) people tend to move over a few buildings and spend most of their time in the same building; and (iii) there is a slight dependence among buildings, even those with high independence power receive user visits from other buildings on campus. Globally, we reveal that (i) our metrics capture places that impact the number of visits in their neighborhood; (ii) cities in the same continent have similar independence patterns; and (iii) places with a high number of visitation and city central areas are the regions with the highest degree of independence.

We describe a model for polarization in multi-agent systems based on Esteban and Ray's standard measure of polarization from economics. Agents evolve by updating their beliefs (opinions) based on an underlying influence graph, as in the standard DeGroot model for social learning, but under a confirmation bias; i.e., a discounting of opinions of agents with dissimilar views. We show that even under this bias polarization eventually vanishes (converges to zero) if the influence graph is strongly-connected. If the influence graph is a regular symmetric circulation, we determine the unique belief value to which all agents converge. Our more insightful result establishes that, under some natural assumptions, if polarization does not eventually vanish then either there is a disconnected subgroup of agents, or some agent influences others more than she is influenced. We also show that polarization does not necessarily vanish in weakly-connected graphs under confirmation bias. We illustrate our model with a series of case studies and simulations, and show how it relates to the classic DeGroot model for social learning., 24 pages, 6 figures. Pre-print of work to appear in the 41st International Conference on Formal Techniques for Distributed Objects, Components, and Systems (FORTE 2021). arXiv admin note: text overlap with arXiv:2012.02703

International audience

International audience; Propionibacterium freudenreichii is a Gram-positive dairy probiotic bacterial species that has been used as a ripening starter in the production of Swiss-type cheese for a long time. It has been exploited for the optimization of cheese production, including ripening capacities and aroma compounds production, but also for the production of vitamin B12 and organic acids. Furthermore, it has emerged in the probiotics landscape owing to several beneficial traits, including tolerance to stress in the gastrointestinal tract, adhesion to host cells, anti-pathogenic activity, anticancer potential and immunomodulatory properties. These beneficial properties have been confirmed with in vitro and in vivo investigations, using several omics approaches that allowed the identification of important molecular actors, such as surface proteins, short-chain fatty acids and bifidogenic factors. The diversity within the species was shown to be an important aspect to take into consideration, since many of these properties were strain-dependent. New studies should dive further into the molecular mechanisms related to the beneficial properties of this species and of its products, while considering the complexities of strain diversity and the interactions with the host and its microbiota. This chapter reviews current knowledge on the possible impact of P. freudenreichii on human health.

Species from OCBILs (old, climatically buffered, infertile landscapes) are expected to exhibit reduced dispersability, linked to long-term stable environmental conditions. We tested the prediction of limited dispersability in plant communities in campo rupestre, a megadiverse OCBIL grassland. In a field experiment, we sampled sticky and funnel traps for 12 months along paired preserved and disturbed plots to estimate and compare annual seed density and richness. Our community-level seed rain assessment suggested widespread seed limitation in both preserved and disturbed areas, expressed by the low seed density in traps (average of 2.6 seeds/m2/day) and remarkably low seed density found for 90% of the morphospecies. Although seed density in campo rupestre was much lower than for other grasslands, species richness (92 seed morphospecies) was the highest reported in the literature. Higher seed density and species richness were captured in funnel traps, especially during the rainy season. Approximately 32% of morphospecies were registered exclusively in disturbed plots and 25% exclusively in preserved plots. This limited seed dispersability is of particular relevance for a better understanding of seed ecology and resilience in campo rupestre and may partially explain the poor recovery of these disturbed areas after soil removal.

Tropical forests are converted at an alarming rate for agricultural use and pastureland, but also regrow naturally through secondary succession. For successful forest restoration, it is essential to understand the mechanisms of secondary succession. These mechanisms may vary across forest types, but analyses across broad spatial scales are lacking. Here, we analyse forest recovery using 1,403 plots that differ in age since agricultural abandonment from 50 sites across the Neotropics. We analyse changes in community composition using species-specific stem wood density (WD), which is a key trait for plant growth, survival and forest carbon storage. In wet forest, succession proceeds from low towards high community WD (acquisitive towards conservative trait values), in line with standard successional theory. However, in dry forest, succession proceeds from high towards low community WD (conservative towards acquisitive trait values), probably because high WD reflects drought tolerance in harsh early successional environments. Dry season intensity drives WD recovery by influencing the start and trajectory of succession, resulting in convergence of the community WD over time as vegetation cover builds up. These ecological insights can be used to improve species selection for reforestation. Reforestation species selected to establish a first protective canopy layer should, among other criteria, ideally have a similar WD to the early successional communities that dominate under the prevailing macroclimatic conditions.

Transient evolution and adjustment to changing tectonic and climatic boundary conditions is an essential attribute of landscapes. We present a new approach to detect and quantify transience in slow erosion landscapes over 100 ka timescales. We compare curvature and cosmogenic nuclides measurements (10Be and 26Al) at hilltop sites with predictions of hillslope diffusion theory, in the slowly evolving quartzitic Serra do Cipó range in SE Brazil, and we observe a distinctive signature of an acceleration of denudation. The timing of this increase cannot be unequivocally associated with a single climatic event but is consistent with climatically-modulated important fluctuations in precipitation and erosion in this area during Middle and Late Pleistocene.

Herbivory is ubiquitous. Despite being a potential driver of plant distribution and performance, herbivory remains largely undocumented. Some early attempts have been made to review, globally, how much leaf area is removed through insect feeding. Kozlov et al., in one of the most comprehensive reviews regarding global patterns of herbivory, have compiled published studies regarding foliar removal and sampled data on global herbivory levels using a standardized protocol. However, in the review by Kozlov et al., only 15 sampling sites, comprising 33 plant species, were evaluated in tropical areas around the globe. In Brazil, which ranks first in terms of plant biodiversity, with a total of 46,097 species, almost half (43%) being endemic, a single data point was sampled, covering only two plant species. In an attempt to increase knowledge regarding herbivory in tropical plant species and to provide the raw data needed to test general hypotheses related to plant–herbivore interactions across large spatial scales, we proposed a joint, collaborative network to evaluate tropical herbivory. This network allowed us to update and expand the data on insect herbivory in tropical and temperate plant species. Our data set, collected with a standardized protocol, covers 45 sampling sites from nine countries and includes leaf herbivory measurements of 57,239 leaves from 209 species of vascular plants belonging to 65 families from tropical and temperate regions. They expand previous data sets by including a total of 32 sampling sites from tropical areas around the globe, comprising 152 species, 146 of them being sampled in Brazil. For temperate areas, it includes 13 sampling sites, comprising 59 species. Thus, when compared to the most recent comprehensive review of insect herbivory (Kozlov et al.), our data set has increased the base of available data for the tropical plants more than 460% (from 33 to 152 species) and the Brazilian sampling was increased 7,300% (from 2 to 146 species). Data on precise levels of herbivory are presented for more than 57,000 leaves worldwide. There are no copyright restrictions. Please cite this paper when using the current data in publications; the authors request to be informed how the data is used in the publications.

Predicting how we humans move within space and time is becoming a central topic in many scientific domains, ranging from epidemic propagation, urban planning to ride-sharing. However, current works neglect individuals' preferences for exploration and discovery of new places. Yet, noveltyseeking activities appear to have significant consequences on the ability to understand and predict individuals' trajectories. In this work, we propose a new approach for the identification of moments of novelty-seeking. Subsequently, we construct individuals' mobility profiles based on their exploration inclinations-Scouters (i.e., extreme explorers), Routiners (i.e., extreme returners), and Regulars (i.e., without extreme behavior).

The pervasiveness of smartphones has modeled our lives, the social norms, and structure that dictate human behavior now directly influence the way individuals interact with network services and demand resources or content. From this scenario, identifying key locations in cities is central in human mobility investigation as well as for societal problem comprehension. In this context, we propose the first graph-based methodology in the literature to quantify the power of point-of-interests (POIs) over its vicinity by means of user mobility trajectories. Different from literature, we consider the flow of people in our analysis, instead of the number of neighbor POIs or their structural locations in the city. Thus, we modeled POI's visits using the multiflow graph model where each POI is a node and the transitions of users among POIs are a weighted direct edge. Using this multiflow graph model, we compute the attract, support, and independence powers. The attract power and support power measure how many visits a POI gather from and disseminate over its neighborhood, respectively. Moreover, the independence power captures the capacity of POI to receive visitors independently from other POIs. We tested our methodology on well-known University Campus mobility datasets and validated on Location-Based Social Networks (LBSNs) datasets from various cities around the world. Our findings show that in University campus: (i) buildings have low support power and attract power; (ii) people tend to move over a few buildings and spend most of their time in the same building; and (iii) there is a slight dependence among buildings, even those with high independence power receive user visits from other buildings on campus. Globally, we reveal that: (i) our metrics capture places that impact the number of visits in their neighborhood; (ii) cities in the same continent have similar independence patterns; and (iii) places with a high number of visitation and city central areas are the regions with the highest degree of independence.

Whenrobots physically interact with the environment, compliant behaviors should be imposed to prevent damages to all entities involved in the interaction. Moreover, during physical interactions, appropriate pose controllers are usually based on the robot dynamics, in which the ill-conditioning of the joint-space inertia matrix may lead to poor performance or even instability. When the control is not precise, large interaction forces may appear due to disturbed end-effector poses, resulting in unsafe interactions. To overcome these problems, we propose a task-space admittance controller in which the inertia matrix conditioning is adapted online. To this end, the control architecture consists of an admittance controller in the outer loop, which changes the reference trajectory to the robot end-effector to achieve a desired compliant behavior; and an adaptive inertia matrix conditioning controller in the inner loop to track this trajectory and improve the closed-loop performance. We evaluated the proposed architecture on a KUKA LWR4+ robot and compared it, via rigorous statistical analyses, to an architecture in which the proposed inner motion controller was replaced by two widely used ones. The admittance controller with adaptive inertia conditioning presents better performance than with a controller based on the inverse dynamics with feedback linearization, and similar results when compared to the PID controller with gravity compensation in the inner loop.

Objectives Patients with impaired kidney function have a significantly slower decrease of procalcitonin (PCT) levels during infection. Our aim was to study PCT-guided antibiotic stewardship and clinical outcomes in patients with impairments of kidney function as assessed by creatinine levels measured upon hospital admission. Methods We pooled and analyzed individual data from 15 randomized controlled trials who were randomly assigned to receive antibiotic therapy based on a PCT-algorithms or based on standard of care. We stratified patients on the initial glomerular filtration rate (GFR, ml/min/1.73 m2) in three groups (GFR >90 [chronic kidney disease; CKD 1], GFR 15–89 [CKD 2–4] and GFR Results Mean duration of antibiotic treatment was significantly shorter in PCT-guided (n=2,492) compared to control patients (n=2,510) (9.5–7.6 days; adjusted difference in days −2.01 [95% CI, −2.45 to −1.58]). CKD 5 patients had overall longer treatment durations, but a 2.5-day reduction in treatment duration was still found in patients receiving in PCT-guided care (11.3 vs. 8.6 days [95% CI −3.59 to −1.40]). There were 397 deaths in 2,492 PCT-group patients (15.9%) compared to 460 deaths in 2,510 control patients (18.3%) (adjusted odds ratio, 0.88 [95% CI 0.78 to 0.98)]. Effects of PCT-guidance on antibiotic treatment duration and mortality were similar in subgroups stratified by infection type and clinical setting (p interaction >0.05). Conclusions This individual patient data meta-analysis confirms that the use of PCT in patients with impaired kidney function, as assessed by admission creatinine levels, is associated with shorter antibiotic courses and lower mortality rates.

We aimed to investigate the combined effects of aerobic exercise (EXE) and cocoa flavanol (COCOA) supplementation on performance, metabolic parameters, and inflammatory and lipid profiles in obese insulin-resistant rats. Therefore, 32 male Wistar rats (230–250 g) were fed a high-fat diet and a fructose-rich beverage for 30 days to induce insulin resistance. Next, the rats were randomized into four groups, orally administered placebo solution or COCOA supplementation (45 mg·kg−1), and either remained sedentary or were subjected to EXE on a treadmill at 60% peak velocity for 30 min, for 8 weeks. Blood samples and peripheral tissues were collected and processed to analyze metabolic and inflammatory parameters, lipid profiles, and morphological parameters. Supplementation with COCOA and EXE improved physical performance and attenuated body mass gain, adipose index, and adipocyte area. When analyzed as individual interventions, supplementation with COCOA and EXE improved glucose intolerance and the lipid profile reduced the concentrations of leptin, glucose, and insulin, and reduced homeostasis assessment index (all effects were p p p p

This paper aims to characterize the relocation of warehouses in the Sao Paulo Metropolitan Region (SPMR) considering the spatial structure of changes in warehouse locations. We also discuss the potential factors that could attract warehouses to their location, especially in peripheral regions. The study encompasses the period between 1992 and 2017 and analyzes the influence of geographical, economics, road infrastructure, municipality service tax rate, cargo theft, and real estate prices on logistics facility location. The results show no evidence of logistics sprawl in SPMR during the studied period, although a small sprawl appeared between 2010 and 2017, moving the barycenter to the Northwestern direction of the SPMR. The main factors that influence the decision to move the warehouses are the low cost of land, lower tax, and a well-served infrastructure with highway intersections. There is a positive spatial correlation between warehouse per capita and cargo theft.

International audience; A hardware configuration is a set of processors and their frequency levels in a multi-core heterogeneous system. This paper presents a compiler-based technique to match functions with hardware configurations. Such a technique consists in using multivariate linear regression to associate function arguments with particular hardware configurations. By showing that this classification space tends to be convex in practice, this paper demonstrates that linear regression is not only an efficient tool to map computations to heterogeneous hardware, but also an effective one. To demonstrate the viability of multivariate linear regression as a way to perform adaptive compilation for heterogeneous architectures, we have implemented our ideas onto the Soot Java bytecode analyzer. Code that we produce can predict the best configuration for a large class of Java and Scala benchmarks running on an Odroid XU4 big.LITTLE board; hence, outperforming prior techniques such as ARM’s GTS and CHOAMP, a recently released static program scheduler.

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International audience; This paper invokes the quantile regression and the M-regression methods which are widely used for time-independent data. We propose a robust quantile estimator for short and long memory time series, as frequently found in financial data. Asymptotic results of the estimator are established for Gaussian time series. The proposed methodology's performance is illustrated by Monte Carlo simulations under different scenarios of time series with additive outliers and asymmetric errors. As an application, the method is used to model the S&P 500 index. As an additional contribution of this paper, the methodology is introduced in mixed models with time series covariates. In this context, a real data set collected in the Greater Vitória area, Brazil, is analyzed to quantify the impact of the particular matter (PM 2.5) levels on the health of children with asthma problems.

WebNLG+ offers two challenges: (i) mapping sets of RDF triples to English or Russian text (generation) and (ii) converting English or Russian text to sets of RDF triples (semantic parsing). Compared to the eponymous WebNLG challenge, WebNLG+ provides an extended dataset that enable the training, evaluation, and comparison of microplanners and semantic parsers. In this paper, we present the results of the generation and semantic parsing task for both English and Russian and provide a brief description of the participating systems., https://aclanthology.org/2020.webnlg-1.7.pdf

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International audience; Introduction Propionibacterium freudenreichii, is a probiotic bacterium, with an established immunomodulatory role. Selected strains indeed induce the release of regulatory IL-10. Extractable surface proteins of the S-layer type (Slp) are involved in such modulation, but the exact mode of interaction with the host remains unknown. Mucositis is a common side effect of cytotoxic chemotherapy characterized by mucosal injury, inflammation, diarrhea, and weight loss. We hypothesized that immunomodulatory P. freudenreichii may mitigate inflammation and that SlpB may be required for such an effect.Extracellular vesicles (EVs) are nanometric spherical structures involved in intercellular communication, whose production is considered a widespread phenomenon in living organisms. Bacterial EVs are associated with several processes that include survival, competition, pathogenesis, and immunomodulation. We hypothesized that, in addition to surface exposure and secretion of proteins, P. freudenreichii may produce EVs and thus export immunomodulatory proteins to interact with the host.MethodsP. freudenreichii CIRM-BIA 129, previously selected for its ability to induce IL-10 release by PBMCs, was administered orally to mice, prior to colitis induction using TNBS.The slpB gene was inactivated by insertional inactivation. Both parental wild type and mutant strains were administered orally to mice, prior to induction of mucositis using 5-FU. The SlpB protein was purified and its effect on cultured human intestinal epithelial cells investigated with respect to cytokines expression.EVs were purified from cell-free culture supernatants of the probiotic strain P. freudenreichii CIRM-BIA 129, prior to physicochemical and functional characterization.ResultsConsumption of P. freudenreichii CIM-BIA129 strain protected mice against TNBS-induced colitis in mice, alleviating severity of symptoms, modulating local and systemic inflammation, as well as colonic oxidative stress and epithelial cell damages.This strain prevented 5-FU-induced mucositis in mice, regulated key markers, including the expression of Claudin-1 (Cld1) and IL-17a (Il17a), as well as the levels of IL-12 and IL-1β cytokines.The slpB gene was mutated by insertional inactivation and the absence of SlpB protein in the resulting mutant was verified. The mutant strain displayed opposite immunomodulatory effect and failed to mitigate induced mucositis.In HT-29 human intestinal epithelial cells P. freudenreichii reduced expression of IL-8 and TNF-α cytokines in LPS-stimulated cells. P. freudenreichii ΔslpB, lacking the SlpB protein, failed to do so. In the same cells, purified SlpB was shown to induce expression of IL-10 in a dose-dependent manner.Extracellular vesicles (EVs), they were purified from cell-free culture supernatants of P. freudenreichii. They showed typical shapes and sizes of EVs and contained a broad range of proteins, including SlpB. EVs modulated inflammatory responses, IL-8 release and NF-κB activity, in HT-29 human intestinal epithelial cells, as well as the NF-κB pathway.DiscussionThis work emphasizes the importance of SlpB in immunomodulatory P. freudenreichii. It constitutes the first report on identification of P. freudenreichii-derived EVs, alongside their physicochemical, biochemical and functional characterization. It opens perspectives for the development of functional foods and other bioactive products in order to help preventing and/or treating inflammatory diseases, and to decrease side effects of chemotherapy.

International audience; This paper presents an advanced characterization of the organic fraction of the top deposit layer collected in a French vertical flow treatment wetland (first stage) in operation in Brazil (two units with different organic deposit layer accumulation times), and compares the results with those obtained from studies in France. The organic and inorganic constituents of the samples collected were analysed by biological, chemical and thermochemical methods. The unit with the organic deposit with longer accumulation time (almost 10 years) was characterized as amature one (organicmatter - OM: 51.3 and 52.7%, thermal index - R-TGA: 0.79and 0.85, humification index - HI: 0.61 and 1.16, respectively for the depths of 0-5 cm and 5-10 cm). The unit with the deposit organic with less than three years of accumulation also presented characteristics of a mature deposit (OM: 61.2%, R-TGA: 0.79, HI: 1.01 for the depth of 0-5 cm), indicating a rapid mineralization of the deposit under the existing subtropical environment. Despite several differences in term of conception, hydraulic and mass loading rates and accumulation rates, the characteristics of the OM of Brazilian deposits were found to be quite similar to the French ones. (C) 2020 Elsevier B.V. All rights reserved.

International audience; Human mobility literature is limited in their ability to capture the novelty-seeking or the exploratory tendency of individuals. Mainly, the vast majority of mobility prediction models rely uniquely on the history of visited locations (as captured in the input dataset) to predict future visits. This hinders the prediction of new unseen places and reduces prediction accuracy. In this paper, we show that a two-dimensional modeling of human mobility, which explicitly captures both regular and exploratory behaviors, yields a powerful characterization of users. Using such model, we identify the existence of three distinct mobility profiles with regard to the exploration phenomenon-Scouters (i.e., extreme explorers), Routiners (i.e., extreme returners), and Regulars (i.e., without extreme behavior). Further, we extract and analyze the mobility traits specific to each profile. We then investigate temporal and spatial patterns in each mobility profile and show the presence of recurrent visiting behavior of individuals even in their novelty-seeking moments. Our results unveil important novelty preferences of people, which are ignored by literature prediction models. Finally, we show that prediction accuracy is dramatically affected by exploration moments of individuals. We then discuss how our profiling methodology could be leveraged to improve prediction.

Viruses have colonized the host germ line on many occasions during evolution to eventually become endogenous. Here, we aimed at investigating whether human testicular germ cells (TGCs) can support such viral invasion by studying HIV interactions with TGCs in vitro. Our results indicate that isolated primary TGCs express alternative HIV-1 receptors, allowing virion binding but not entry. However, HIV-1 entered and integrated into TGCs upon cell-associated infection and produced low levels of viral proteins. In vivo, HIV-1 and SIV DNA was detected in a few TGCs. Molecular landscape analysis showed that TGCs have overall weak antiviral defenses. Altogether, our results indicate that human TGCs can support HIV-1 early replication, including integration, suggesting potential for endogenization in future generations., Viruses have colonized the germ line of our ancestors on several occasions during evolution, leading to the integration in the human genome of viral sequences from over 30 retroviral groups and a few nonretroviruses. Among the recently emerged viruses infecting humans, several target the testis (e.g., human immunodeficiency virus [HIV], Zika virus, and Ebola virus). Here, we aimed to investigate whether human testicular germ cells (TGCs) can support integration by HIV, a contemporary retrovirus that started to spread in the human population during the last century. We report that albeit alternative receptors enabled HIV-1 binding to TGCs, HIV virions failed to infect TGCs in vitro. Nevertheless, exposure of TGCs to infected lymphocytes, naturally present in the testis from HIV+ men, led to HIV-1 entry, integration, and early protein expression. Similarly, cell-associated infection or bypassing viral entry led to HIV-1 integration in a spermatogonial cell line. Using DNAscope, HIV-1 and simian immunodeficiency virus (SIV) DNA were detected within a few TGCs in the testis from one infected patient, one rhesus macaque, and one African green monkey in vivo. Molecular landscape analysis revealed that early TGCs were enriched in HIV early cofactors up to integration and had overall low antiviral defenses compared with testicular macrophages and Sertoli cells. In conclusion, our study reveals that TGCs can support the entry and integration of HIV upon cell-associated infection. This could represent a way for this contemporary virus to integrate into our germ line and become endogenous in the future, as happened during human evolution for a number of viruses. IMPORTANCE Viruses have colonized the host germ line on many occasions during evolution to eventually become endogenous. Here, we aimed at investigating whether human testicular germ cells (TGCs) can support such viral invasion by studying HIV interactions with TGCs in vitro. Our results indicate that isolated primary TGCs express alternative HIV-1 receptors, allowing virion binding but not entry. However, HIV-1 entered and integrated into TGCs upon cell-associated infection and produced low levels of viral proteins. In vivo, HIV-1 and SIV DNA was detected in a few TGCs. Molecular landscape analysis showed that TGCs have overall weak antiviral defenses. Altogether, our results indicate that human TGCs can support HIV-1 early replication, including integration, suggesting potential for endogenization in future generations.

Made available in DSpace on 2020-12-12T01:36:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 The historical focus in research and policy on forest restoration and temperate ecosystems has created misunderstandings for the restoration of tropical and subtropical old-growth grassy biomes (TGB). Such misconceptions have detrimental consequences for biodiversity, ecosystem services, and human livelihoods in woodlands, savannas, and grasslands worldwide. Here, we demystify TGB restoration myths to promote a positive agenda to increase the likelihood of success of ambitious landscape-scale restoration goals of nonforest ecosystems. The 10 TGB restoration myths are: (1) grasslands originate from degraded forests, (2) tree cover is a reliable indicator of habitat quality, (3) planting trees is always good for biodiversity and ecosystem services, (4) grasslands are biodiversity-poor and provide few ecosystem services, (5) enhancing plant nutrition is needed in restoration, (6) disturbance is detrimental, (7) techniques used to restore temperate grasslands also work for TGB, (8) grasslands represent early stages of forest succession, (9) grassland restoration is only about grasses, and (10) grassland restoration is fast. By demystifying TGB restoration, we hope that policymakers, scientists, and restorationists come to understand and embrace the value of these ecosystems and are motivated to establish policies, standards, indicators, and techniques that enhance the success of TGB restoration. We must abandon misperceptions and misunderstandings of TGB ecology that result in ill-conceived policies and build an informed and compelling global ecosystem restoration agenda that maintains and improves the well-being of all inhabitants of grassy biomes. Departamento de Genética Ecologia e Evolução Instituto de Ciências Biológicas Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627 School of Biological Sciences University of Western Australia Department of Biological Sciences University of Cape Town Floresta Estadual de Assis Instituto Florestal do Estado de São Paulo, P.O. Box 104 Lab of Vegetation Ecology Instituto de Biociências Universidade Estadual Paulista (UNESP), Av. 24A, 1515 Centre for Functional Biodiversity School of Life Sciences University of KwaZulu-Natal Department of Plant Biology Institute of Biology University of Campinas—UNICAMP Departamento de Botânica Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500 Departamento de Ciências Ambientais (DCA) Instituto de Florestas (IF) Universidade Federal Rural do Rio de Janeiro—UFRRJ, BR 465, Km 07 Unit for Environmental Sciences and Management North-West University Department of Plant Sciences University of California Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale (IMBE) Avignon Université UMR CNRS IRD Aix Marseille Université IUT Site Agroparc, BP 61207 Lab of Vegetation Ecology Instituto de Biociências Universidade Estadual Paulista (UNESP), Av. 24A, 1515

International audience; Achieving food security at a global scale while protecting the environment, as envisioned in the Sustainable Development Goals, will require a complex process of collaboration and the integration of analyses at multiple scales. Agricultural and land use models are increasingly being used to bridge the global/local divide, particularly as a means to envision future land access, use and management in different agricultural production systems. This special issue contributes to our understanding of global modeling, governance and land use change. Specifically, it provides insights into the question of: how do the ways of knowing and governing affect the politics of environmental protection and agriculture? The papers in this special issue bring reflexive questions of knowledge production, public policy and civic engagement into the epistemic spaces of scientific and technological development, both as a means to improve the way we model and to understand the implications of governing by models.

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The 2016 United States presidential election was marked by the abuse of targeted advertising on Facebook. Concerned with the risk of the same kind of abuse to happen in the 2018 Brazilian elections, we designed and deployed an independent auditing system to monitor political ads on Facebook in Brazil. To do that we first adapted a browser plugin to gather ads from the timeline of volunteers using Facebook. We managed to convince more than 2000 volunteers to help our project and install our tool. Then, we use a Convolution Neural Network (CNN) to detect political Facebook ads using word embeddings. To evaluate our approach, we manually label a data collection of 10k ads as political or non-political and then we provide an in-depth evaluation of proposed approach for identifying political ads by comparing it with classic supervised machine learning methods. Finally, we deployed a real system that shows the ads identified as related to politics. We noticed that not all political ads we detected were present in the Facebook Ad Library for political ads. Our results emphasize the importance of enforcement mechanisms for declaring political ads and the need for independent auditing platforms.

International audience; Staphylococcus aureus, a versatile Gram-positive bacterium, is the main cause of bone and joint infections (BJI), which are prone to recurrence. The inflammasome is an immune signaling platform that assembles after pathogen recognition. It activates proteases, most notably caspase-1 that proteolytically matures and promotes the secretion of mature IL-1 beta and IL-18. The role of inflammasomes and caspase-1 in the secretion of mature IL-1 beta and in the defence of S. aureus-infected osteoblasts has not yet been fully investigated. We show here that S. aureus-infected osteoblast-like MG-63 but not caspase-1 knock-out CASP1( -/-)MG-63 cells, which were generated using CRISPR-Cas9 technology, activate the inflammasome as monitored by the release of mature IL-1 beta. The effect was strain-dependent. The use of S. aureus deletion and complemented phenole soluble modulins (PSMs) mutants demonstrated a key role of PSMs in inflammasomes-related IL-1 beta production. Furthermore, we found that the lack of caspase-1 in CASP1( -/-)MG-63 cells impairs their defense functions, as bacterial clearance was drastically decreased in CASP1( -/-) MG-63 compared to wild-type cells. Our results demonstrate that osteoblast-like MG-63 cells play an important role in the immune response against S. aureus infection through inflammasomes activation and establish a crucial role of caspase-1 in bacterial clearance.

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International audience; Background and Purpose: The artemisinin derivative, artemether, has antimalarial activity with potential neurotoxic and cardiotoxic effects. Artemether in nanocapsules (NC‐ATM) is more efficient than free artemether for reducing parasitaemia and increasing survival of Plasmodium berghei‐infected mice. NCs also prevent prolongation of the QT interval of the ECG. Here, we assessed cellular cardiotoxicity of artemether and how this toxicity was prevented by nanoencapsulation.Experimental Approach: Mice were treated with NC‐ATM orally (120 mg·kg−1 twice daily) for 4 days. Other mice received free artemether, blank NCs, and vehicle for comparison. We measured single‐cell contraction, intracellular Ca2+ transient using fluorescent Indo‐1AM Ca2+ dye, and electrical activity using the patch‐clamp technique in freshly isolated left ventricular myocytes. The acute effect of free artemether was also tested on cardiomyocytes of untreated animals.Key Results:Artemether prolonged action potentials (AP) upon acute exposure (at 0.1, 1, and 10 μM) of cardiomyocytes from untreated mice or after in vivo treatment. This prolongation was unrelated to blockade of K+ currents, increased Ca2+ currents or promotion of a sustained Na+ current. AP lengthening was abolished by the NCX inhibitor SEA‐0400. Artemether promoted irregular Ca2+ transients during pacing and spontaneous Ca2+ events during resting periods. NC‐ATM prevented all effects. Blank NCs had no effects compared with vehicle.Conclusion and Implications: Artemether induced NCX‐dependent AP lengthening (explaining QTc prolongation) and disrupted Ca2+ handling, both effects increasing pro‐arrhythmogenic risks. NCs prevented these adverse effects, providing a safe alternative to the use of artemether alone, especially to treat malaria.