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Reduced regulatory complexity associated with the evolutionary transition to sociality from cockroaches to termites despite evolutionary parallels with Hymenoptera
No full textAbstract In social species, the phenotypic diversity within a single species has often been associated with more complex genetic regulation. Transcription factors (TFs) being key to genetic regulation, have been studied in the origins of eusociality in Hymenoptera (Bees, Ants and Wasps) but less so in Blattodea (Cockroaches and Termites). Here we show that the social transition in Blattodea, from cockroaches to termites, displays similar patterns of regulatory change to those found in Hymenoptera. Specifically, by analysing 3 cockroach and 5 termite genomes, we find more TF families with relaxed selection compared to intensified selection and lineage-specific gene family expansions in termites. We also find that genes under selection support neotenic caste determination. There are key differences in TF regulation in comparison with Hymenoptera with contractions in TF gene families and reduced diversity in enriched DNA binding motifs of TFs. Furthermore, we show that with increased social complexity TF activating domain diversity, one of the evolutionary and structural building blocks of TFs, decreases with gene family size while DNA binding domain diversity and number increases. This study highlights similarities in social transitions between Hymenoptera and Blattodea, with evidence of large changes in transcriptional regulation followed by lineage specific adaptations. We also show that phenotypic diversity in termites does not necessitate greater transcriptional complexity
Invasive macroalgae shape chemical and microbial waterscapes on coral reefs
No full textInternational audienceOver the past decades, human impacts have changed the structure of tropical benthic reef communities towards coral depletion and macroalgal proliferation. However, how these changes have modified chemical and microbial waterscapes is poorly known. Here, we assessed how the experimental removal of macroalgal assemblages influences the chemical and microbial composition of two reef boundary layers, the benthic and the momentum. Chemical and microbial waterscapes were spatially structured, both horizontally and vertically, according to macroalgal dominance and boundary layers. Microbes associated with reef degradation were enriched in the boundary layers surrounding macroalgal-dominated substrata. Dominant macroalgae were surrounded by a distinct chemical pool of diverse lipid classes (e.g., diterpenoids and glycerolipids) and labile organic matter (e.g., organooxygen compounds), which diffused from algal tissues to boundary layers according to their polarity. Finally, our results highlighted strong co-variations between specific algal-derived metabolites and planktonic microbes, giving insight into their roles in coral reef functioning and resilience
Enhancing therapeutic reasoning: key insights and recommendations for education in prescribing
No full textAbstract Background Despite efforts to improve undergraduate clinical pharmacology & therapeutics (CPT) education, prescribing errors are still made regularly. To improve CPT education and daily prescribing, it is crucial to understand how therapeutic reasoning works. Therefore, the aim of this study was to gain insight into the therapeutic reasoning process. Methods A narrative literature review has been performed for literature on cognitive psychology and diagnostic and therapeutic reasoning. Results Based on these insights, The European Model of Therapeutic Reasoning has been developed, building upon earlier models and insights from cognitive psychology. In this model, it can be assumed that when a diagnosis is made, a primary, automatic response as to what to prescribe arises based on pattern recognition via therapy scripts (type 1 thinking). At some point, this response may be evaluated by the reflective mind (using metacognition). If it is found to be incorrect or incomplete, an alternative response must be formulated through a slower, more analytical and deliberative process, known as type 2 thinking. Metacognition monitors the reasoning process and helps a person to form new therapy scripts after they have chosen an effective therapy. Experienced physicians have more and richer therapy scripts, mostly based on experience and enabling conditions, instead of textbook knowledge, and therefore their type 1 response is more often correct. Conclusion Because of the important role of metacognition in therapeutic reasoning, more attention should be paid to metacognition in CPT education. Both trainees and teachers should be aware of the possibility to monitor and influence these cognitive processes. Further research is required to investigate the applicability of these insights and the adaptability of educational approaches to therapeutic reasoning
Detachment Faulting and Mantle Exhumation Beneath an Allochthonous Carbonate Cover: Insights From the Gouffre Georges (Lherz Massif, Pyrenees, France)
No full textInternational audienceThe Cretaceous North Pyrenean hyperextended rift system recorded HT-LP metamorphism in the pre- and syn-rift sedimentary cover during lithospheric mantle exhumation. We describe and analyze for the first time the rocks exposed in the Gouffre Georges, a deep cave in the Lherz peridotite massif (Ari and egrave;ge, France). The cave walls expose the lithospheric detachment between the Mesozoic pre-rift sedimentary cover hanging wall and the mantle rock footwall. Extensional structures have been preserved despite the positive inversion of the North Pyrenean rift system during the Pyrenean Orogeny. The extension direction is downdip WNW, consistent with rifting models of transtensional left-lateral regime during the final stage of rifting. Field, microstructural, and petrographic data document a continuum of extensional deformation from high- to low-temperature conditions. This detachment fault underwent high-temperature hydrothermalism, with a possible contribution from evaporite-born fluids. New observations also strongly suggest the formation of a hot, low-viscosity material along the detachment interface. This material was then injected in the uppermost part of the peridotite body during the final stage of mantle exhumation. We consider three possible scenarios: (a) partial melting at the base of the pre-hyperextension carbonates; (b) precipitation from carbonate-rich hydrothermal fluids; and (c) flow of hyper-ductile marble due to extreme plasticity of calcite under high temperature. Likewise, the base of the pre-hyperextension cover recorded intense hydraulic and tectonic brecciation during extension. As indicated by their lack of syn-rift sedimentary reworking, the Lherz peridotite recorded partial exhumation at the base of the Jurassic sedimentary cover, without exposure to the seafloor
Incidence and duration of human papillomavirus infections in young women: insights from a bimonthly follow-up cohort
No full textInternational audienceBackground. We studied the duration of HPV detection and risk of (re-) detection for 25 HPV genotypes in a cohort of 132 women followed every eight weeks for up to two years between 2016 and 2020. Participants were between 18 and 25 years old at inclusion and half of them were vaccinated against HPV. They were recruited near the University and the STI detection centre in Montpellier, France.Methods. We used genotype-specific longitudinal data to characterise the dynamics of HPV-detected episodes. We investigated the contribution of viral and host factors to the variations in the duration of HPV detection, and the time before (re-)detection of the same genotype using multivariate Cox regression models with frailty at the patient level.Findings. We detected at least one HPV episode in 74% of the participants and re-detected the same genotype in 47% of them. Covariates related to socio-economic difficulties were associated with a lower risk of detectability loss (hazard ratio 0.45 with a 95% confidence interval, CI, from 0.21 to 0.97).The number of lifetime sexual partners was strongly associated with an increased risk of new positive detection (hazard ratio 2.40 with a 95%CI from 1.07 to 5.39). In contrast, vaccination was associated with a lower risk of displaying incident infections (hazard ratio of 0.64 with a 95%CI from 0.43 to 0.96).Conclusion.In the short term, vaccination shows clear signs of protection against new HPV detections, including for some genotypes not targeted by the vaccine, such as HPV31 and HPV51.</p
Opportunities for Earth observation to inform risk management for ocean tipping points
No full textInternational audienceAs climate change continues, the likelihood of passing critical thresholds or tipping points increases. Hence, there is a need to advance the science for detecting such thresholds. In this paper, we assess the needs and opportunities for Earth Observation (EO, here understood to refer to satellite observations) to inform society in responding to the risks associated with ten potential large-scale ocean tipping elements: Atlantic Meridional Overturning Circulation; Atlantic Subpolar Gyre; Beaufort Gyre; Arctic halocline; Kuroshio Large Meander; deoxygenation; phytoplankton; zooplankton; higher level ecosystems (including fisheries); and marine biodiversity. We review current scientific understanding and identify specific EO and related modelling needs for each of these tipping elements. We draw out some generic points that apply across several of the elements. These common points include the importance of maintaining long-term, consistent time series; the need to combine EO data consistently with in situ data types (including subsurface), for example through data assimilation; and the need to reduce or work with current mismatches in resolution (in both directions) between climate models and EO datasets. Our analysis shows that developing EO, modelling and prediction systems together, with understanding of the strengths and limitations of each, provides many promising paths towards monitoring and early warning systems for tipping, and towards the development of the next generation of climate models
TROLL 4.0: representing water and carbon fluxes, leaf phenology, and intraspecific trait variation in a mixed-species individual-based forest dynamics model – Part 2: Model evaluation for two Amazonian sites
No full textInternational audienceTROLL 4.0 is an individual-based forest dynamics model that jointly simulates the structure, diversity and functioning of tropical forests, including their water balance, carbon fluxes and leaf phenology, while accounting for intraspecific trait variation for a large number of species. In a companion paper, we describe how the model represents the physiological and demographic processes that control the tree life cycle in a one-metre-resolution spatially-explicit scene and uses plant functional traits measurable in the field to parameterize such processes across species and individuals (Maréchaux et al., submitted companion paper). Here we evaluate the performance of TROLL 4.0 for two Amazonian sites with contrasting soil and climate properties. We assessed the model's ability to represent forest structure and composition using lidar-derived canopy height distributions and forest inventories combined with information on plant functional traits. We also evaluated the model's ability to represent carbon and water fluxes, as well as leaf area variation, at daily and fortnightly resolution over a decade, using detailed information from on-site eddy covariance towers, satellite data and ground-based or air-borne lidar data. We finally compared the responses of carbon and water fluxes to environmental drivers between simulated and observed data. Overall, TROLL 4.0 provided a realistic representation of forests at both sites. The simulated canopy height distribution showed a high correlation coefficient (CC) with observed aerial and satellite data (CC>0.92), while the species and functional composition were well represented (CC>0.75). TROLL 4.0 also realistically simulated the seasonal variability of carbon and water fluxes (CC>0.46) and their responses to environmental drivers, while capturing temporal variations in leaf area (CC>0.76) and its partitioning in leaf age cohorts. However, TROLL 4.0 overestimated annual gross primary productivity at both sites (mean RMSEP=0.94 kgC m-2 yr-1) and evapotranspiration at one site (mean RMSEP=0.75 mm day-1), likely due to an underestimation of the soil water depletion and stomatal control during the dry season. This evaluation highlights the potential of TROLL 4.0 to represent ecosystem fluxes and the structure and diversity of plant communities at a fine resolution, paving the way for model predictions of the effects of climate change, fragmentation and forest management on forest structure and dynamics
Runtime Monitoring for AI-based Systems: An application to runway detection
No full textInternational audienceAutomated runway detection is a rapidly growing domain in avionics. Recent advancements in the machine learning (ML) community have enabled the development of cutting-edge neural networks (NN) for this specific task. However, given the critical nature of automated flight operations, the reliability and safety of these systems must be rigorously ensured. Runtime monitoring approaches have emerged as promising solutions to enhance these properties. Monitors are components designed to continuously supervise the behaviour and outputs of NNs during runtime. They are generally categorised into two main types: rule-based and data-driven. Rule-based monitors verify that safety properties are satisfied, making them suitable for scenarios with well-defined safety requirements. In contrast, data-driven monitors are trained on antecedents to learn patterns of erroneous or unexpected behaviour. This poster explores the main challenges and preliminary solutions for designing and evaluating such monitors. Main challenges would include (1) Which types of threats should the monitor address? (2) Which kind of error detection mechanism should be used? and (3) How should the monitor be evaluated with respect to overall system safety
Going Dutch: European distribution of non-native land flatworm species belonging to Geoplaninae and Bipaliinae with focus on the Netherlands
No full textInternational audienceNon-native land flatworms can have a negative impact on local ecosystems, due to their voracious appetites for earthworms or snails. Accurate knowledge on the distribution of non-native populations of land flatworms is necessary to design effective policy to control their spread across Europe. The aim of this study is to address the spatiotemporal distribution of selected species of non-native land flatworms (Geoplaninae and Bipaliinae) in the Netherlands, and provide their current distribution and introduction pathways in a pan-European perspective. Specimens of Obama spp., Bipalium kewense and Diversibipalium multilineatum were reported across selected Dutch gardens, greenhouses, plant nurseries or garden centers. European distribution of these planarians species was reconstructed using previously published datasets and from records available on GBIF. Morphological species identification was supported by DNA barcoding using a portion of the 28S rDNA marker. Introduction pathways were addressed via haplotype networks based on COI mtDNA. In total, 27 specimens of non-native land flatworms were collected in the Netherlands. Their different spatiotemporal distribution pattern indicates differences in tolerance to environmental conditions in Northern Europe between B. kewense restricted to greenhouses and D. multilineatum found in gardens. Generally, an increasing trend in the number of records of Obama nungara is observed in the Netherlands and in Europe, with the highest number of records per country reported in France (1.428) followed by the Netherlands (149) and Italy (64). The high numbers of France are, however, artificial and originate from communication towards the public, which has not been as pronounced in other European countries. Genetic analyses suggest multiple introductions of O. nungara in Europe. The combination of morphological and molecular species identification revealed the presence of Obama anthropophila being the first record of this species outside its native range in Brazil. Our results further support the established status of these species in Europe and highlight the importance of citizen scientists in non-native species research