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Characterizing suicidal intent among suicidal adolescents: a systematic review
No full textInternational audienceAbstract Background Suicidal intent contributes both to the assessment of suicide risk and to long-term prognosis in adults. Although suicidal intent is a key component in suicide risk assessment, its specific features and clinical implications in adolescents after a suicide attempt remain underexplored in the literature. However, it could represent an improvement in the assessment and prognosis of adolescent suicidal crisis. The aim of this study is to describe how suicidal intent manifests in adolescents after a suicide attempt, and how it relates to associated clinical and contextual characteristics. Method We conducted a systematic review assessing suicidal intent in adolescents after a suicide attempt adhering to PRISMA guidelines. Five databases were searched up to September 2023. Seventeen studies met the inclusion criteria. We excluded studies focusing solely on suicidal ideation or on non-suicidal self-injury. Data were extracted and synthesized narratively. Study quality was assessed using standard tools. Results Several studies suggest that suicidal intent may be more frequently reported in older adolescents, with a significant difference before and after the age of 16. High suicidal intent seems to be more frequently linked to internalized disorders. While suicidal intent does not appear directly linked to the lethality of the attempt, the highest level of suicidal intent reported across previous attempts may represent a prognostic marker for later suicide mortality. Conclusion It seems essential to refine existing assessment tools or develop new ones specifically adapted to adolescents, in order to assess suicidal intent while taking into account the specificities of the adolescent population. This would help optimize interventions and support for both the patient and their family
<b>I</b> nvestigating neonatal sepsis: anti-Infectives, diagnostics and Guidelines used in Health sysTems across sub-Saharan Africa – The INSIGHTS study
No full textInternational audienceBackground Sepsis is a leading cause of neonatal mortality in sub-Saharan Africa (SSA), where microbiological diagnostic capacity and antibiotic access are limited. High antimicrobial resistance (AMR) rates limit the effectiveness of current treatment guidelines, with concern that available antibiotics are rarely adequate treatment for neonatal sepsis in the region. Methods A cross-sectional online survey was electronically distributed in English, French and Portuguese to neonatal clinicians across SSA between April and June 2025. Questions focused on the management of neonatal sepsis including diagnostic, antibiotic and guideline use. Responses were analysed descriptively and presented as percentages of the total number of responses. Results Of 169 responses (40/48 countries; 83.3%) from SSA, 71.6% were senior doctors, 88.8% managed neonatal sepsis at least weekly and 58.0% worked in central healthcare facilities. 14.9% (95% CI 10.3% to 21.0%) of respondents never and 28.6% (CI 22.3% to 35.8%) less than half of the time received blood culture results in time to impact patient care. Guidelines were almost universally used (97.6% (CI 94.0% to 99.1%)). The most common guideline for early-onset neonatal sepsis advised amoxicillin/ampicillin plus aminoglycosides (46.4% of responses (CI 39.1% to 54.0%)). 50.3% (CI 42.8% to 57.7%) of respondents had difficulties accessing antibiotics, with carbapenems and piperacillin-tazobactam least accessible. 45.4% (CI 38.0% to 53.1%) had attempted to author local guidelines with insufficient local AMR data (45.6% (CI 35.7% to 55.8%)) the most common barrier to guideline development. Conclusions This large survey highlighted widespread challenges in diagnostic and antibiotic access for neonatal sepsis in SSA. We find that clinicians rely on guidelines to guide starting antibiotics and to guide agent choice. Their practices reflect advice in global guidelines. Attempts to author locally applicable guidelines are hindered by insufficient AMR data. These findings strengthen calls to improve microbiological diagnostic access and support data sharing to generate evidence-based, locally appropriate guidelines
Holocene potential natural vegetation in Europe: Evaluating the model spread with three dynamical vegetation models
No full textInternational audienceThe period of the early Holocene in Europe is marked by climate warming as Earth comes out of the last glacial period and is followed by the emergence of agriculture and animal husbandry in the second half of the period. Increased human influence had profound impacts on the land surface, but the Holocene climate evolution also drove some changes that are intertwined with it. Deciphering the role of each in the vegetation evolution is becoming more difficult as one progresses to the earlier parts of the Holocene here human induced impacts were fainter. Within this general context, we aim at understanding how much Dynamical Vegetation Models (DGVMs) differ in their representation of Potential Natural Vegetation (PNV) in Europe during the mid-to late Holocene (8.5 k.a. BP to 1900 A. D.). We ran three different DGVMs, SEIB-DGVM, ORCHIDEE-DGVM and CARAIB, in Europe, for six time-slices and forced them with identical climatic imputs obtained from the iLOVECLIM Earth system model (downscaled and bias-corrected). Results are then compared with pollen-based reconstructions from the TERRANOVA database. Overall, the three models have a similar performance in representing the pollenderived vegetation cover at the european scale. However, their results are largely different at regional scales, particularly in mountainous areas and in boreal regions. They also show a very large spread in simulated PFT diversity at the grid cell scale, highlighting the impact of each model's internal dynamics on the results. On a global scale, they all agree on a decreasing match of their results with pollen base reconstructions over time, indicating -as expected -an increase of the human pressure on the landscape.</div
From non-specific biomarker to targeted action: transdiagnostic and sex-specific drivers of high-CRP status in severe mental illness across the FondaMental Advanced Centers of Expertise (FACE) cohorts
No full textInternational audienceBackground and objectives: Low-grade systemic inflammation contributes to the pathophysiology of severe mental illness (SMI) in a substantial subset of patients, who often experience greater disease burden and poorer treatment response. Elevated C-reactive protein (CRP), defined as CRP ≥ 3 mg/L, has been proposed to identify this group, but its non-specificity limits the biomarker's ability to guide targeted intervention. We aimed to determine the most consistent drivers of high CRP across bipolar disorder (BD), schizophrenia (SZ) and major depressive disorder (MDD), and to translate these into clinically actionable intervention targets using robust data-driven methods.Methods: We pooled and harmonised data from three large French national SMI cohorts (n = 7149: 4797 bipolar disorder, 1958 schizophrenia and 394 resistant major depression) and classified participants by CRP ≥ 3 mg/L, as well as an alternative cut-off of 5 mg/L. We applied penalised logistic regression (PLR), random forests (RF) and unsupervised clustering, using 28 biopsychosocial variables to identify robust drivers of high-CRP status. We then grouped these into actionable targets and assessed relative dominance.Results: In total, 30.16% of participants had CRP ≥ 3 mg/L. PLR identified female sex (OR [95% CI]: 1.60 [1.27, 1.93]), higher BMI (OR: 1.09 [1.07, 1.13]), current nicotine dependence (OR: 1.05 [1.02, 1.09]), lower HDL cholesterol (OR: 0.57 [0.44, 0.73]) and smoking (ex-smoker status OR: 0.84 [0.66, 0.98]) as consistent drivers. RF highlighted a similar set of key drivers, also including waist circumference, triglycerides and cardiovascular comorbidities. Clustering of the high-CRP group was almost entirely driven by smoking status and nicotine dependence. When grouped into actionable targets, the identified drivers accounted for 16% of variance in CRP status, with obesity emerging as most dominant contributor. This pattern was most pronounced in females; in males it was more diffuse, with a more prominent role for smoking.Conclusions: We propose a decision tree framework where CRP can serve as a first-line screening marker for inflammation in SMI, with subsequent steps focusing on the main contributing factors to guide targeted interventions. Priority should be given to targeting obesity and metabolic dysregulation. Among females, hyperuricemia represents the next most appropriate target, whereas in males, smoking warrants greater attention. This stepwise approach provides a route from a nonspecific biomarker to targeted treatment strategies and should be validated in prospective studies
GeoDS (v.1.0): a simple Geographical DownScaling model for long-term precipitation data over complex terrains
No full textInternational audienceGlobal climate models offer the most comprehensive description of the climate system and its internal processes to date but current computational capabilities typically restrict their spatial resolution to the order of hundreds of kilometers when long-term (millennial or longer) simulations are needed. Over the years, various downscaling techniques have been developed to generate fine scale data from climate models outputs but they often exhibit important limitations when applied over long periods of time. Building on previous efforts, we present a simple topography-based model (GeoDS) to downscale precipitation fields in complex areas, adapted to paleoclimate studies involving multimillennia simulations. With a limited amount of inputs from a climate model and high resolved geographical information, the model computes, for each time step and every grid point, a topographic exposure index used to distribute precipitation into a high-resolution spatial grid. This dimensionless quantity represents the exposure of surfaces to dominant windward incoming airflows, assumed to bring most of the humidity, and only depends on large scale winds and terrain configuration. The model is first tested under current climate conditions over part of the European Alpine region due to the availability of field data for comparison; the complexity of both regional topography and climate conditions making it a good test of the proposed methodology. The relative effects of the model's parameters are assessed as well as the capacity of GeoDS to reproduce the spatial precipitation distribution of a well-resolved gridded target dataset. Despite uncertainties regarding the correct wind fields to choose as input, and the dependency of the model to the temporal resolution of the large-scale data to downscale, we show that the procedure is able to capture most of the patterns occur-ring at fine spatial scale while being computationally inexpensive. We also demonstrate that the physical base underlying our work grants the model valuable robustness when used outside the calibration framework. This notably opens promising prospects for the application of GeoDS in paleoclimate contexts while providing a flexible, open source and well documented downscaling tool for the climate community.</div
Detection of ozone recovery in the Arctic from ground-based measurements
No full textInternational audienceContrary to the Antarctic, where ozone recovery has been observed for about a decade, the detection of positive ozone trends in the Arctic remains challenging due to higher natural variability of ozone in that region. Using a merging of long-term ozone data from Fourier transform infrared spectrometers, ozonesondes, and Dobson and Brewer spectrophotometers, we present regional long-term trends (2000−2024) for total, stratospheric and tropospheric ozone. First, ground-based measurements are cross-compared to two satellite data sets (MEGRIDOP and IASI-CDR). This enables the detection of drifted ground-based data sets we further exclude from our study. We then use a representativeness study based on CAMS re-analysis data to define regions for which representative trends with reduced uncertainties are obtained by combining data sets from different instruments and stations. Annual and seasonal trends are calculated using a multiple linear regression technique involving a set of proxies that represent physical processes influencing the natural ozone variability. Annual trends indicate increasing total ozone over the Arctic, and are statistically significant over Canada and Reykjavik (+2.1 %/decade) and North-West Europe (Harestua and Lerwick, +0.7 %/decade). Ozone recovery is also observed over Canada in the mid-stratosphere (+2.0 %/decade) and over the North Pole region (Canada and Ny-Ålesund) in the upper stratosphere (+2.1 to +3.8 %/decade). By analysing the sensitivity of the ozone trends to the proxies, we observe a slow down of the expected ozone recovery, especially in the lower stratosphere, due to stratospheric cooling (-0.6 %/decade) and to the increase of volume of polar stratospheric clouds (-0.8 %/decade)
The impact of photochemical loss of VOCs from anthropogenic and biogenic emissions on ozone formation mechanisms
No full textInternational audienceVolatile organic compounds (VOCs) are key precursors of ozone (O3) formations and are readily oxidized by atmospheric oxidants, resulting in significant photochemical losses before in-situ observations. Ignoring these photochemically consumed VOCs (C-VOCs) introduces uncertainties in O3 formation sensitivity and un- derestimates the impact of various VOCs emissions on radical cycling, hindering the understanding of photo- chemical losses from key emissions to O3 formation. This study quantified the impact of C-VOCs from anthropogenic and biogenic emissions on O3 formation mechanisms by integrating field observations with an observation-based model. The results indicated that an average of 20.6 % of total VOCs was lost due to photochemical processes in June, mainly alkenes and aromatics. Accounting for C-VOCs extended the period of O3 formation sensitivity in the transitional regime, with consumed biogenic VOCs (C-BVOCs) playing a key role in the afternoon in modulating O3 sensitivity. C-BVOCs enhanced radical sink processes dominated by HO2+RO2 and HO2+HO2 reactions, suppressing the ROX cycle, thereby shifting O3 sensitivity toward the NOx-limited regime. Incorporating C-VOCs increased the net O3 production rate by 14.3 ppb h 1, primarily driven by C- BVOCs. This study provides new insights into the impact of different VOCs emissions on O3 formation through quantified photochemical losses
Parallel Dynamic Programming for the Exact Computation of Density of State for 2D Spin-Crossover Nanomaterials
No full textInternational audienceWe discuss the design, the analysis and the parallel implementation of a dynamic programming approach for the computation of the density of state in the simulation of spin-crossover nanoparticles. The motivation is the computation of a Hamiltonian, which is usually approximated using Monte Carlo techniques. However, physicists need better control of the accuracy of this approximation. An exact counting algorithm allows this error to be controlled, and also measures the impact on accuracy for the entire simulation. We propose an exact parallel counting algorithm and its two-level parallel implementation to tackle nanoscale problems on HPC architecture. We discuss its scalability and feasibility for 2D grids of n molecules. The new algorithm enables the exact computation for a three-variable density of state at nanoscale, which is seen as intractable. A comparison between the expectation of the model and implementation is proposed. The parallel complexity achieved is O(n^{5/2}2^{sqrt(n)}) and the results allow the prediction of never-before-seen phenomena
Measuring cloud optical depth with a balloonborne microlidar operated from the stratosphere
No full textInternational audienceThe Balloonborne Cloud Observing micrOLidar (BeCOOL) has been developed to be operated onboard a stratospheric balloon in order to monitor the atmosphere below 20 km, more particularly thin ice clouds. This lidar system was designed to maintain a high level of performance while keeping its mass below 6 kg and limiting its power consumption to 4 W on average. Several balloons embarking BeCOOL instruments have been launched from the Tropics (Seychelles Islands, −4.68 S +55.45 E) during the STRATEOLE-2 campaign organized by the French Space Agency (Centre National d'Etudes Spatiales, CNES) in autumn and winter 2021−2022. The microlidar system, its operational performances, and the data processing to estimate optical properties are described. BeCOOL is able to measure optical depth of upper level thin ice clouds down to 2 × 10−5. It is possible to constrain the lidar ratio when the cloud optical depth is larger than 3 × 10−2. In this case, the optical depth relative uncertainty is less than 10 %
Updated global and regional trends of stratospheric ozone profiles
No full textInternational audienceWe present updated evaluation of stratospheric ozone profile trends in the 60°S-60°N latitude range using long-term ground-based and satellite climate data records, as well as simulations by chemistry-climate models. The trends are evaluated using the LOTUS (Long-term Ozone Trends and Uncertainties in the Stratosphere) regression model.Analyses of satellite data confirm the statistically significant positive ozone trends in the period 2000-2024 in the upper stratosphere of ~1-3 %decade -1 , with larger trends at mid-latitudes compared to the tropics. The trends are slightly positive or close to zero in the middle stratosphere, and mostly negative, -1-2 %decade -1 , in the lower stratosphere; but they are not statistically significant. The morphology and magnitude of ozone trends are similar to previous analyses (2000-2020 trends).Ozone trends in 2000-2024 predicted by climate model simulations are in good agreement with combined satellite trends. In the upper stratosphere, models predict a slightly stronger ozone recovery than observations. In the lower stratosphere, both models and satellite observations report negative trends of in the tropics, while modelled ozone trends are slightly positive at mid-latitudes.Ozone profile trends over several stations estimated from ground-based records capture the same overall vertical pattern of ozone trends as merged gridded satellite datasets. Analyses of regional ozone profile trends in 2003-2024 using merged satellite datasets confirmed the previous observations of a longitudinal structure in ozone trends in the NH mid-latitude stratosphere, with positive trends over Scandinavia and negative trends over Siberia. However, the magnitude of this dipole-like structure is reduced compared to previous analyses