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Disease burden of patients with moderate to severe ulcerative colitis: A French multicenter real-life study (THEFAR)
No full textInternational audienceBackground: Specific studies on the impact of ulcerative colitis (UC) and bowel urgency (BU) on disability and quality of life (QoL) of patients on advanced therapies are missing.Methods: Clinical and therapeutic management data were collected by Gastroenterologists from adult patients with UC treated with advanced therapies. Patients reported outcomes on QoL were collected using patient-reported questionnaires.Results: Forty-one sites enrolled 293 patients. Median age was 42.0 years, median disease duration was 6.0 years. 38.9 % had active disease (partial Mayo score>1). Median treatment duration was 16.9 months. 166 (57.0 %) patients had BU [median UNRS=2] and 78.3 % had fecal incontinence [median Wexner score=8.0]. Moderate to severe disability (IBD-Disk score≥40) was reported in 37.8 % patients. BU patients had a higher Wexner score [10.0 vs 5.2, p < 0.0001] and moderate to severe disability rate (53.7% vs 16.9 %, p < 0.0001), lower QoL and work productivity than those in BU remission: mean EQ-5D-5 L utility [0.846 vs 0.943, p < 0.0001], VAS for self-rated health [66.2 vs 82.1, p < 0.0001], and overall work impairment [35.7% vs 11.3 %, p < 0.0001].Conclusion: The burden of moderate to severe UC, especially in patients with BU, is high. These findings highlight that BU control remains an unmet medical need in UC patients and underscore the need for new innovative treatments
Dynamic reciprocal contributions between Indigenous communities and cultural keystone species: A study case in Western Ecuador
No full textInternational audienceAbstract The reciprocal contributions concept provides a holistic approach to understanding management of natural resources in social‐ecological systems. The purpose of this study was to understand how Indigenous peoples build reciprocal contributions with cultural keystone species (CKS) through their dynamic knowledge systems. We explore the cultural value and reciprocal contributions between an endemic palm locally known as tagua ( Phytelephas aequatorialis Spruce) and the Indigenous Commune of Salanguillo in western Ecuador. We use a multidisciplinary, mixed methods approach (including participant observation, focus group discussions, talking maps and social surveys) to identify reciprocity at three human dimensions (institutional‐social‐political, biophysical and symbolic–linguistic–cultural). Our study revealed multiple and diverse reciprocal contributions between people and tagua across all dimensions, and the tagua palm was identified as a CKS. Interactions with tagua reflect broader social‐ecological changes in the region. Reciprocal contributions between tagua and the Commune are built through direct individual experience, but also rely on communal and national institutional agreements. Integration of Indigenous knowledge with the global environmental discourse underpins the place‐based learning strategies for the sustainable use and management of tagua and human well‐being. Read the free Plain Language Summary for this article on the Journal blog
Osteotomies for genu varum: should we always correct at the tibia? A multicenter analysis of practices in France
No full textInternational audienc
Tests of General Relativity with GWTC-3
No full texthttps://journals.aps.org/prd/accepted/17075Qf4Z7b11729787e85f1c18faca230d51e013International audienceThe ever-increasing number of detections of gravitational waves (GWs) from compact binaries by the Advanced LIGO and Advanced Virgo detectors allows us to perform ever-more sensitive tests of general relativity (GR) in the dynamical and strong-field regime of gravity. We perform a suite of tests of GR using the compact binary signals observed during the second half of the third observing run of those detectors. We restrict our analysis to the 15 confident signals that have false alarm rates . In addition to signals consistent with binary black hole (BH) mergers, the new events include GW200115_042309, a signal consistent with a neutron star--BH merger. We find the residual power, after subtracting the best fit waveform from the data for each event, to be consistent with the detector noise. Additionally, we find all the post-Newtonian deformation coefficients to be consistent with the predictions from GR, with an improvement by a factor of ~2 in the -1PN parameter. We also find that the spin-induced quadrupole moments of the binary BH constituents are consistent with those of Kerr BHs in GR. We find no evidence for dispersion of GWs, non-GR modes of polarization, or post-merger echoes in the events that were analyzed. We update the bound on the mass of the graviton, at 90% credibility, to . The final mass and final spin as inferred from the pre-merger and post-merger parts of the waveform are consistent with each other. The studies of the properties of the remnant BHs, including deviations of the quasi-normal mode frequencies and damping times, show consistency with the predictions of GR. In addition to considering signals individually, we also combine results from the catalog of GW signals to calculate more precise population constraints. We find no evidence in support of physics beyond GR
Computing shortest closed curves on non-orientable surfaces
No full textInternational audienceWe initiate the study of computing shortest non-separating simple closed curves with some given topological properties on non-orientable surfaces. While, for orientable surfaces, any two non-separating simple closed curves are related by a self-homeomorphism of the surface, and computing shortest such curves has been vastly studied, for non-orientable ones the classification of non-separating simple closed curves up to ambient homeomorphism is subtler, depending on whether the curve is one-sided or two-sided, and whether it is orienting or not (whether it cuts the surface into an orientable one).We prove that computing a shortest orienting (weakly) simple closed curve on a non-orientable combinatorial surface is NP-hard but fixed-parameter tractable in the genus of the surface. In contrast, we can compute a shortest non-separating non-orienting (weakly) simple closed curve with given sidedness in g^O(1).n logn time, where g is the genus and n the size of the surface.For these algorithms, we develop tools that can be of independent interest, to compute a variation on canonical systems of loops for non-orientable surfaces based on the computation of an orienting curve, and some covering spaces that are essentially quotients of homology covers
Proof Techniques for Behavioural Relations Based on Unique-Solutions of Equations and Inequations
No full textInternational audienceWe give an overview of recent work aiming at strengthening Milner's technique of unique-solution of equations. This technique, originally introduced for CCS, is used to establish weak bisimilarity of processes. We review two improvements of the technique. The first one builds on the contraction behavioural preorder. The second one relaxes the conditions under which unique-solution can be applied by focusing on divergence in processes. We present applications of these techniques to reason about higher-order languages. We discuss how the two approaches, involving contractions and divergences, have been adapted and enriched, and compare them to each other.</div
Climate Trend in the Eastern Arctic: LST, Vegetation, and Regional Climate Parameters
No full textInternational audienceThis study examines the 24-year spatial and temporal variability of the thermal regime measured by LST, vegetation distribution by NDVI, and its relationship with the shift in climatic zones, derived from optimal reanalysis in Yakutia. Changes in land surface temperature (LST) play a pivotal role in the climate system and exert a considerable influence on ecosystems, hydrological regimes and human activities. However, the origin of the effect of climatic parameters, including precipitation, snow cover, and surface air temperature, on the spatial and temporal dynamics of LSTs remains poorly explored in the Siberian Arctic and Yakutia. The research conducted focuses on the relationships between LST and these climatic parameters in Yakutia from 2001 to 2024 based on the use of daily and monthly land surface temperature (LST) data derived from the MODIS MOD21C3.061 product, at 1 km spatial resolution. LST MODIS data combined with Climatic parameters (surface air temperature and precipitation) were obtained from climate reanalyses (GHCN-CAMS and CRU TS v4.05). The Mann-Kendall test and Sen's slope estimation were utilised to ascertain seasonal trends. The results suggest that during the spring and autumn months, the rise in LST is closely associated with a reduction in snow cover duration and an increase in air temperature. A strong positive correlation was observed between the increase in land surface temperature (LST) and the decrease in snow cover duration, as well as the rise in surface air temperature during the 24 years of monitoring. In contrast, during the summer months, variations in precipitation become a pivotal factor. A robust correlation between LST and precipitation was observed, as evidenced by the positive and negative values of Kendall's tau coefficient, contingent on the prevailing landscape and climatic conditions. The method of long-term trends of LST & NDVI data once again shows spatial and seasonal differences in the causes of significant changes in these variables. Snow cover plays a major role in LST changes, which demonstrates the prevalence of positive trends in the spring and autumn seasons. Climatic shifts are significant between the base period 1961-1990 and the present period 1991-2020, next 2021-2024
Reliable and Robust Watermarking for Data Flooding against Ransomware Random Techniques
No full textInternational audienceData Flooding Against Ransomware (DFaR) techniques combat ransomware through decoy files that can reveal a ransomware's activity and reduce the effectiveness and efficiency of attacks by confounding legitimate user files and competing for IO resource access of the attacked host. While effective, existing DFaR random strategies (which flood a user system with realistic yet random-content decoy files) face challenges during restoration, due to the necessity of pre-attack file lists to discriminate between proper and decoy files (the latter should be removed to restore the system to its pre-attack state). To tackle this issue, we present a watermarking-based approach that embeds imperceptible watermarks in random-content decoy files. Our technique preserves the indistinguishability of decoys from user files to attackers, while providing users with a reliable mechanism to differentiate between authentic and decoy content, obviating the need for pre-attack file lists. We present experimental evaluations that demonstrate that our watermarking technique a) imposes minimal-to-medium computational overhead (depending on user-configurable parameters) compared to existing random-content flooding methods (i.e., it is efficient when contrasting ransomware and restoring a user's system) and b) it provides strong resistance against adversarial inference attacks
Distributed serverless function scheduling in ad-hoc drone networks
No full textInternational audienceThe increasing use of Unmanned Aerial Vehicles (UAVs) in critical applications, such as disaster response, compels efficient communication and computation frameworks for highly dynamic ad-hoc networks. We present an interpretation of Function-as-a-Service serverless computing within the distributed settings of drone swarms to address their peculiar challenges in functionality deployment, resource allocation, and mission adaptability. We propose a novel two-layer network overlay architecture, combining a gossip-based topology management layer with a function scheduling layer to support distributed function scheduling. Our system introduces a declarative language of Ad-Hoc Allocation Priority Policies (AHAPP), tailored for ad-hoc drone networks, enabling flexible function deployment based on resource constraints and operational needs. The resulting combination addresses the volatility of UAVs networks by supporting execution semantics for stable and dynamic topology scenarios, function offloading, and resilience to network disruptions. We present experiments confirming that the features provided by our proposal support the efficient execution of serverless functions in adhoc drone networks, effectively handling their dynamic and heterogeneous nature, while achieving strong performance in terms of reliability, schedulin