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Describing the structural complexity of seabeds is of primary importance for a number of geomorphological, hydrodynamical and ecological issues. Aiming to bring a decisive insight on the long-term development of a unified view, the present study reports on a comparative multi-site analysis of high resolution topography surveys in rough nearshore environments. The nine study sites have been selected to cover a wide variety of topographical features, including rocky and coral seabeds. The topography data has been processed to separate roughness and bathymetry-related terrain features, allowing to perform a comprehensive spectral and statistical analysis of each site. A series of roughness metrics have been tested to identify the most relevant estimators of the bottom roughness at each site. The spectral analysis highlights the systematic presence of a self-affine range of variable extension and spectral slope. The standard deviation of the seabed elevation varies from 0.04 to 0.77 m. The statistical and multi-scale analysis performed on the whole set of roughness metrics allows to identify connection between metrics and therefore to propose a reduced set of relevant roughness estimators. A more general emphasis is placed on the need to properly define a unified framework when reconstructing roughness statistics and bathymetry from fine seabed topographical data., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Sous et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Objective: Clinicians report low confidence assessing cutaneous lupus erythematosus (CLE) lesions, especially for patients who identify as Black, Indigenous, and People of Color (BIPOC) who are historically excluded from educational materials. To address this, we created an online, interactive module teaching an approach to assessing CLE across skin tones and measured its impact on medical knowledge and confidence., Methods: Our team created a module with case-based methods to introduce an approach to CLE, common mimicking rashes, and tips for photographing cutaneous lesions in BIPOC. Graduate medical trainees from five academic institutions completed the module. Using surveys and pre-post testing, we assessed changes in medical knowledge and clinical confidence along with learner satisfaction, comparing responses using Wilcoxon-signed rank tests and chi square analysis. We assessed the module's representation of light, medium, and dark skin tones with chi square analysis., Results: The module represented light, medium, and dark skin tones (χ 2 = 4.788, P = 0.091) among 102 images (77.5%, n = 79) were novel images from authors' personal libraries. Ninety-four participants completed the postmodule test and evaluation survey. Analyses revealed significant improvement in medical knowledge identifying serologic studies associated with subacute CLE (χ 2 = 14.035, P < 0.001) and describing how to photograph rashes (χ 2 = 38.211, P < 0.001). Participants reported improved confidence across all learning objectives after module completion (P < 0.001)., Conclusion: This module is the first to introduce an approach to assessing CLE across skin tones, effectively increasing medical knowledge and confidence among graduate medical trainees., (© 2023 American College of Rheumatology.)

Compositional data are a special kind of data, represented as a proportion carrying relative information. Although this type of data is widely spread, no solution exists to deal with the cases where the classes are not well balanced. After describing compositional data imbalance, this paper proposes an adaptation of the original Synthetic Minority Oversampling TEchnique (SMOTE) to deal with compositional data imbalance. The new approach, called SMOTE for Compositional Data (SMOTE-CD), generates synthetic examples by computing a linear combination of selected existing data points, using compositional data operations. The performance of the SMOTE-CD is tested with three different regressors (Gradient Boosting tree, Neural Networks, Dirichlet regressor) applied to two real datasets and to synthetic generated data, and the performance is evaluated using accuracy, cross-entropy, F1-score, R2 score and RMSE. The results show improvements across all metrics, but the impact of oversampling on performance varies depending on the model and the data. In some cases, oversampling may lead to a decrease in performance for the majority class. However, for the real data, the best performance across all models is achieved when oversampling is used. Notably, the F1-score is consistently increased with oversampling. Unlike the original technique, the performance is not improved when combining oversampling of the minority classes and undersampling of the majority class. The Python package smote-cd implements the method and is available online., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Nguyen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Vertical dynamics of microplastics (MPs) in the water column are complex and not fully understood due to the diversity of environmental MPs and the impact of weathering and biofouling on their dynamical properties. In this study, we investigate the effects of the particle properties and biofilm on the vertical (settling or rising) velocity of microplastic sheets and fibers under laboratory conditions. The experiments focus on three types of MPs (polyester PES fibers, polyethylene terephthalate PET sheets, and polypropylene PP sheets) of nine sizes and two degrees of biological colonization. Even though pristine PES fibers and PET sheets had a similar density, the sinking velocity of fibers was much smaller and independent of their length. The settling or rising velocity of sheets increased with the particle size up to a threshold and then decreased in the wake of horizontal oscillations in large particles. Biofilms had unexpected effects on vertical velocities. Irregular biofilm distributions can trigger motion instabilities that decrease settling velocities of sheets despite the increase in density. Biofilms can also modify the orientation of fibers, which may increase their settling velocity. Finally, we selected the most performant theoretical formulation for each type of particle and proposed modifications to consider the effect of biofilm distribution.