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Multiple Threshold‐Selection Methods Are Needed to Binarise Species Distribution Model Predictions
No full textInternational audienceAim Probabilities of occurrence predicted by species distribution models (SDMs) are routinely binarised based on a threshold that maximises the true skill statistic. Recently, the true skill statistic is criticised for favouring overprediction when species' prevalence is low. We aim to assess the effect of three alternative threshold‐selection methods on predicted range sizes and changes therein under climate change across a large number of species in Europe. Location Europe. Methods We fitted SDMs for 1677 vascular plant species, using species observations from 431,179 vegetation plots as response variables and climate, soil and topographic variables as predictors. We used the SDMs to quantify current and future range sizes of each species under mild and severe climate change scenarios, each combined with two dispersal assumptions (no and unlimited dispersal) and using four threshold‐selection methods: maximising true skill statistic (TSS), minimising the difference between sensitivity and specificity (DSS), maximising Matthew's correlation coefficient (MCC) and maximising F‐measure (F). Further, we assessed prediction errors for each threshold‐selection method in relation to species prevalence. Results We found that SDM outputs binarised with TSS resulted in the largest predicted ranges and the smallest future range contractions. For current climate conditions, median range sizes were 1.3, 3.6 and 9.2 times larger when binarised with TSS than with DSS, MCC and F, respectively. Under severe climate change without dispersal, median range size declines were 56%, 61%, 79% and 88% with TSS, DSS, MCC and F, respectively. Binarisation based on TSS tended to result in the highest overprediction rates and lowest underprediction rates, while this was the opposite with F. Main Conclusions We recommend choosing the threshold‐selection method based on the goals and scope of the study, while carefully considering the trade‐offs between overprediction and underprediction. Alternatively, we recommend using multiple threshold‐selection methods to quantify the uncertainty in the binarisation
Perceived Digital Well-Being Scale in the United States and United Kingdom: Psychometric Validation Study
No full textInternational audienceBackground Digital well-being encourages balanced mobile use. The Perceived Digital Well-Being in Adolescence Scale measures this in adolescents but has been validated only in Slovenia, raising questions about its relevance for other age groups and cultural contexts. Objective This study had three primary objectives: (1) confirm the 3-factor structure of an English version of the Perceived Digital Well-Being in Adolescence Scale, renamed the Perceived Digital Well-Being Scale (PDWS), in samples of young adults from the United States and the United Kingdom; (2) examine the associations between PDWS dimensions and participants’ sociodemographic characteristics; and (3) explore the relationships between PDWS scores and patterns of smartphone use. Methods A total of 1854 young adults from the United States and the United Kingdom (ages 18‐25 years; mean 22.4, SD 2.1; 892, 48.1% female, 872, 47.0% male, 90, 4.9% nonbinary) participated in an online survey including the PDWS, digital flourishing, and digital stress measures. Data were analyzed using descriptive statistics, confirmatory factor analysis, correlations, t tests, chi-squared tests, and moderation-mediation analysis. Results Smartphone screen time and smartphone time for nonessential activities were statistically higher in the US sample than in the UK sample (mean 6.95 vs mean 6.13; t 1852 =4.97; P <.001; d =0.27 and mean 3.62 vs mean 3.29; t 1852 =5.57; P <.001; d =0.25, respectively). The digital well-being total score was statistically higher among US participants when compared with the UK counterparts (mean 3.49 vs mean 3.38; t 1852 =3.33; P <.001; d =0.15). Male participants were significantly more represented among the group with higher PDWB scores ( χ 2 136 =478.45; P <.001). Confirmatory factor analysis supported the adequacy of the 3-factor model (emotional, social, and cognitive), indicating strong model fit (critical indices ≥0.90). Evidence of convergent validity was established through significant associations between PDWS scores and measures of digital flourishing and digital stress (most correlation coefficients being significant at P <.001). Measurement invariance testing confirmed the scale’s equivalence across US and UK samples ( χ 2 246 change=17.90; P =.21); however, strict invariance across gender (male vs female) was not supported ( χ 2 246 change=200.91; P <.001). Gender, sexual orientation, relationship status, ethnicity, socioeconomic status, and education level significantly influenced PDWS scores. Gender and socioeconomic status also moderated the relationship between smartphone use or screen time and PDWS scores ( b =0.048; P =.03 and b =0.020; P =.03, respectively), indicating that these factors affect how smartphone usage relates to psychological distress or well-being in different demographic groups. Conclusions The PDWS showed good psychometric properties in the US and UK samples. The scale offers a promising tool for identifying individuals at risk of adverse outcomes associated with digital connectivity
Plan de continuité d’activité en cas de cyberattaque : sécurisation du circuit des chimiothérapies en établissement de santé
No full textL’informatisation des établissements de santé est une réelle avancée dans les établissements de santé. Néanmoins, celle-ci peut être un véritable inconvénient, notamment en cas de cyberattaque. Au CHB, de nombreux logiciels sont utilisés pour optimiser la prise en charge et la sécurité du patient. Au sein de l’Unité de Préparation des Cytotoxiques (UPC), le logiciel indispensable est Asclépios®. En cas d’indisponibilité de ce logiciel, la prise en charge d’un patient nécessitant une chimiothérapie injectable est impactée. L’objectif de ce travail est de créer un plan de continuité d’activité (PCA) de l’UPC en cas de cyberattaque afin de permettre la continuité de soins. Il se base sur l’élaboration d’une cartographie de l’ensemble du processus de réalisation d’une chimiothérapie injectable. Les différents processus sont analysés pour aboutir à une analyse des modes de défaillances, de leurs effets et de leur criticité (AMDEC). L’AMDEC permet de hiérarchiser les risques liés à une cyberattaque afin de trouver des solutions dégradées. Des fiches réflexes spécifiques à chaque dysfonctionnement et composées de PCA et de plans de reprise d’activité (PRA) découlent de cette AMDEC. Ce PCA permet de faciliter la prise en charge d’un patient nécessitant une chimiothérapie injectable en cas de cyberattaque. Il doit être le plus adaptable possible pour être fonctionnel sur la totalité de l’attaque. L’anticipation est le maître-mot d’une cyberattaque pour améliorer la résilience des professionnels de santé
Croyances sur la contrôlabilité des difficultés psychologiques et santé mentale : quelles populations cibler dans l’enseignement supérieur français ?
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Addressing Bottlenecks to Achieve High-Energy Sodium-Ion Cells Using Tin Anodes or Anode-Free
No full textInternational audienceSodium-ion batteries (NIBs), as a complementary energy storage device for Li-ion batteries, are swiftly making their way into high-power applications market. However, further progress in NIBs requires high energy density. This necessitates shifting from the commonly used hard carbon (HC) anodes to alloy anodes such as Bi/Sn/Sb, etc., while overcoming the problems these materials pose with regard to volume changes and interfacial reactivity. This article focuses on issues related to the chemistry of Na3V2(PO4)2F3 (NVPF)|Sn-HC based cells using 1M NaPF6 in diglyme as electrolyte and proposes solutions. Through operando, ex-situ, and post-mortem (electro)chemical characterizations, we demonstrate that glyme electrolytes remain stable under reduction. However, their low oxidative stability gives rise to parasitic species that interfere with and poison the Sn-HC electrode. This results in poor cycling stability, preventing their use in Naion cells. To mitigate this problem, we propose various solutions, such as (i) using a low-voltage cathode, (ii) coating Sn with a protective layer, and (iii) introducing chemical traps such as Nametal, Na15Sn4, or NaxC between the separators. Of all these solutions, the traps are the most effective, completely suppressing cross-talk poisoning, enabling 100% capacity retention of NVPF|Sn-HC cells over 200 cycles at C/5. Furthermore, we demonstrate that this concept can be extended to anode-free configurations, achieving 91% capacity retention after 80 cycles at C/10. This presents a practical design principle for Na-ion cells with energy densities approaching those of Li-ion systems, and can be adapted to other chemistries susceptible to cross-talk poisoning
Diagnostic relevance of SH2B3 mutations in suspected myeloid malignancies and acute leukemia: insights from a large-scale NGS-based screening study
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Tricuspid vs Bicuspid Aortic Valve Endocarditis
No full textInternational audienceBackground: Bicuspid aortic valve infective endocarditis (BAV-IE) patients exhibit more perivalvular complications as compared to tricuspid aortic valve (TAV) IE.Objectives: We examined symptom-to-diagnosis time in BAV-IE vs TAV-IE and its effect on outcomes.Methods: Consecutive adult patients (≥18 years) with native aortic valve IE were retrospectively reviewed from all Mayo Clinic US sites from 2015 to 2021. Clinical features, microbiology, and outcomes were extracted from electronic health records. IE-related major adverse cardiovascular events (IE-related MACE) were perivalvular infection extension, septic embolism, heart failure, and/or surgery.Results: There were 52 BAV-IE patients (mean age 47 ± 15 years, 85% [44/52] male) and 244 with TAV-IE (mean age 65 ± 14 years, 72% [177/244] male). Compared to TAV-IE, BAV-IE patients showed higher prevalence of streptococcal infections (54% [28/52] vs28% [69/244]; P = 0.0004), and higher suspected dental procedure source (10 [5/52] vs 2% [5/244]; P = 0.006). BAV-IE patients exhibited delayed symptom-to-diagnosis time (median 34 vs7 days; P < 0.0001). IE-related major adverse cardiovascular event (IE-MACE) was higher in BAV-IE (96% [50/52] vs 64% [156/244]; P < 0.0001). Age (OR: 0.74, 95% CI: 0.59 to 0.92 per 10-years; P = 0.006), BAV(OR: 4.91; CI: 1.08-22.38; P = 0.04), and symptom-to-diagnosis time (OR: 1.23; CI: 1.09-1.38; P = 0.001 per week) were independently associated with IE-MACE. There was a linear 23% increase odds of IE-MACE per week of diagnosis delay. BAV-IE patients had superior 4-year survival but became similar after age and sex adjustment.Conclusions: BAV-IE patients incur delayed symptom-to-diagnosis time resulting in high IE complication burden, despite predominance of less virulent streptococcal causative microorganisms. These findings call for enhanced IE clinical suspicion in BAV patients and suggest antibiotic prophylaxis may be indicated in these patients
Utilisation du smartphone pour l’examen du fond d’œil : une expérience auprès d’étudiants de deuxième cycle d’études médicales
No full textInternational audiencePurpose. - To evaluate the performance of medical students in learning funduscopy using smart-phones. Methods. - Participants were medical students who were divided into small groups and taught the technique of smartphone funduscopy, first theoretically and then procedurally, with a simulation workshop on a model eye. The technique involved freehand alignment of the smartphone camera axes with a 20 diopter double aspheric lens. They then had to examine 10 patients in a retina clinic and obtain fundus photographs. Evaluation questionnaires were completed by students, supervisors and patients to obtain data on the performance of the examination technique. We aimed to investigate the effects of training on students' self-rated technical skills. Results. - Between September 2022 and April 2023, 27 medical students completing their ophthalmology rotation at our university teaching hospital were enrolled in the study. At the end of a training cycle of ten fundus examinations, students' self-efficacy scores increased significantly from 10.39/20 to 15.48/20, a factor of 1.5 (p < 0.001). On the technical level, the quality of the examination, as rated by the instructor, increased significantly from 11/20 to 16.96/20, a factor of 1.5 (p < 0.001). The quality of the images and the duration of the examination improved with the number of examinations. By the ninth funduscopy, 80% of the images were free of artifacts. Conclusion. - Our study showed that, by using a smartphone in a simulation and then in a clinical setting, students were able to learn and develop their skills in indirect ophthalmoscopy. Their smartphone funduscopy performance improved with training, achieving satisfactory quality after 10 trials.ObjectifÉvaluer les performances d’étudiants de deuxième cycle des études médicales dans la réalisation d’une photographie du fond d’œil à l’aide d’un smartphone.Matériel et méthodesAu début de leur stage hospitalier, les étudiants ont reçu un enseignement dirigé portant sur la technique de l’ophtalmoscopie indirecte au smartphone, d’abord théorique puis procédural, avec un atelier de simulation sur un œil artificiel conçu à des fins pédagogiques. La technique impliquait un alignement manuel, sans support stable, de l’axe de la caméra du smartphone avec celui d’une lentille convergente de 20 dioptries. Ils devaient ensuite chacun examiner dix patients en consultation et obtenir une photographie du fond d’œil. Des questionnaires d’évaluation ont été complétés par les étudiants, les encadrants et les patients afin d’évaluer la performance de la technique d’examen.RésultatsEntre septembre 2022 et avril 2023, 27 étudiants en médecine, stagiaires dans le service d’ophtalmologie du centre universitaire, ont participé à l’étude. Au terme d’un cycle d’entraînement de dix examens du fond d’œil, leur sentiment d’efficacité personnelle a significativement progressé, passant de 10,39/20 à 15,48/20, soit un facteur de 1,5 (p < 0,001). Sur le plan technique, la qualité du geste, telle qu’évaluée par l’encadrant, a significativement progressé, passant de 11/20 à 16,96/20, soit une amélioration d’un facteur de 1,5 (p < 0,001). La qualité des clichés et la durée d’examen se sont améliorées avec le nombre d’essais. À partir du neuvième fond d’œil, 80 % des clichés étaient exempts d’artéfacts.ConclusionNotre étude a montré que les étudiants étaient capables d’apprendre la technique de l’ophtalmoscopie indirecte au smartphone, d’abord en simulation, puis en pratique clinique, et d’améliorer significativement leurs performances, atteignant une qualité satisfaisante après dix essais
