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This paper develops an analytical framework to quantify how flow-induced pore-pressure fields drive initial bedform deformation in soft, saturated porous beds. Starting from Biot’s poroelastic framework, the governing equations are simplified under assumptions of low soil stiffness, low permeability, and distinct time-scale separation between fast surface flow and slower bed responses. Closed-form analytical solutions are derived for both harmonic and localized rectangular bedforms, revealing asymmetric pore-pressure distributions characterized by negative upstream and positive downstream gradients. These gradients induce upward seepage at the pit shoulders, which is expected to promote erosion, while enhancing deposition within the pit interior. The proposed model provides a computationally efficient and physically interpretable framework for evaluating pore-pressure-driven bedform responses. Its applicability extends to practical scenarios such as bridge pier scour, pipeline burial, and coastal structure stability assessments.

The behavioural tendency to expand sleep opportunity to compensate for prior sleep loss is referred to as 'sleep extension.' It is believed that sleep extension (here referred to as 'sleep opportunity extension' [SOE]) is the primary perpetuating factor explaining the transition from acute to chronic insomnia. Recently, this proposition was prospectively evaluated by assessing how sleep opportunity varied, week-by-week, relative to the incidence of acute and chronic insomnia. Significant differences in sleep opportunity before and after onset of acute insomnia were not detected. In the present analysis, a more granular evaluation was undertaken to assess whether SOE occurs on the nights and/or weekends following poor sleep. The data set (n = 1243) was modelled by group (good sleepers and participants with acute insomnia) for SOE occurring on the nights and weekends following poor nights of sleep (i.e., ≥ 30 min of sleep latency and/or nocturnal wakefulness and/or early morning awakenings) for the post-acute insomnia interval. A linear mixed effects model was used to account for up to one year of night-to-night sleep per participant. During the weekdays, sleep opportunity following a poor night of sleep was not found to increase (overall or by group) (< 5 min). During the weekends, all groups tended to decrease their sleep opportunity. This counterintuitive finding casts further doubt on the proposition that SOE is responsible for the transition between acute insomnia and chronic insomnia. This finding does not, however, change the relevance of addressing the mismatch between sleep opportunity and ability as part of behavioural treatment.

<strong class="journal-contentHeaderColor">Abstract.</strong> Simultaneous characterization of the size and organization of both static and moving sediment particles would help to better understand bedform development in river channels. In the current study, an image-based particle tracking method was developed to measure the pathways of sediment particles in transport and visualize their interactions with evolving sedimentary bedforms in flume experiments. The method is novel because it: i) uses ultraviolet lights, fluorescent paint and image segmentation to obtain size class-specific videos of sediment transport over a mixed bed; ii) applies a blob-detection method included in a standalone software (TracTrac &ndash; Heyman, 2019) to detect and track particles at rest and in motion; and iii) includes a custom post-processing algorithm that includes a grid-based probabilistic motion model to minimize error in the inferred connections between particle positions on a path. We applied the algorithms on a set of videos taken during a laboratory experiment in which a pair of alternate bars and a cross-over central bar were forming in a shallow flume with non-cohesive sand and gravel transport. When the method works well, as it did for the case of particles in the 2.4&ndash;4.0 mm size class (~7 pixels in nominal diameter), the method resulted in an error of +7 % for the number of tracks and -20 % for the average duration of tracks. This degree of accuracy allowed us to analyse the locations of static particles and sediment pathways to show how the active sediment corridor shifted across the frame and then changed angles from the initial trajectories as the set of bars developed. Success of the method is reliant on accurate detection of tracer positions and the ability to predict connections between two identified positions with a motion model. Recommendations are given for application of the method and further testing to reduce reliance on subjective parameters.

Abstract Patagonia and Tierra del Fuego (Austral Andes) are the most glacierised regions in the Southern Hemisphere, where glaciers have experienced significant mass changes in recent decades. Understanding glacier–climate–water interactions is crucial for addressing future climate challenges. Open-access data play a key role in advancing geoscience research, improving models and assessing the impacts of hazards and sea-level rise impacts. Here, we present QFuego-Patagonia, a free glacier-related GIS dataset and web portal covering Patagonia and Tierra del Fuego, which provides essential geospatial information across four scientific topics: Glaciology, Atmosphere, Terrain Models, and Glacial Geology and Geomorphology. This initiative aims to foster interdisciplinary research and collaboration, synthesise current knowledge and establish an advanced glacier data repository that will be continuously updated as new data and insights become available.

Abstract BackgroundThe cultural context influences how mental disorders like depression, are perceived and experienced. Most studies on lived experiences of depression by youths have been done in high-income countries. This has made it difficult for researchers to infer the findings in the context of SSA due to differences in cultures and socio-demographic characteristics. This systematic review thus, seeks to understand how depression is experienced by youths and their guardians in SSA.ObjectiveThis systematic review was done to address two key objectives: to explore and synthesize qualitative studies on the lived experience of depression among youths and their guardians and to identify common themes, and the impact of socio-cultural and contextual factors on the lived experience of depression among youths and their guardians in SSA.MethodologyTwo research assistants independently searched and selected articles from databases such as PubMed, using a set search strategy. Thereafter, two reviewers reviewed and extracted data from the selected articles, analysed it using meta-aggregation techniques. The identified papers underwent an independent quality assessment using the Critical Appraisal Skills Program checklist by the two independent researchers. Through this quality assessment, the risk of bias in the papers was also assessed. We have used the Preferred Reporting Items of Systematic Reviews and Meta-analyses (PRISMA) guidelines in reporting this review.ResultsOur search resulted into 14 unique studies spanning 8 countries in SSA, representing a total of 610 young people (10 to 24 years; 72% females) with lived experience of depression, 297 caregivers and 70 healthcare workers. Findings on the lived experience of youths were aggregated into eleven categories which were further grouped into three main synthesised findings of making sense of depression, mental health systems and services and contextual issues as key issues encompassing their lived experience. Regarding the experience of guardians, three key themes were identified: challenges faced by the guardians, their perception of youth depression and their experience in navigating through the healthcare system.Conclusionthe sociocultural context in SSA determines how the youth experience depression and that symptoms of depression as experiences by youths in SSA may not always match diagnostic criteria developed from the west. The experiences of the guardians have an impact on the young people’s experiences of depression.Systematic review registration: PROSPERO, CRD42024556661

Abstract Concealed active faults constitute potential seismic origins. The Xiangfan-Guangji Fault, acting as the tectonic demarcation between the Yangtze Platform and the Qinling-Dabie Fold Belt, exhibits an exceedingly intricate tectonic evolutionary history. In the Wuhan segment, this fault is entirely overlaid by Cenozoic sediments, and the attributes of its underground spatial configuration remain ambiguous. This circumstance substantially hampers the progress of urban planning and presents a formidable hazard to public safety within the urban precincts of Wuhan. In this research, the shallow seismic reflection technique is utilized to explore the concealed location, geometric characteristics, and distribution pattern of the fault within the Wuhan section. To validate the reliability of the results, boreholes were drilled along the survey lines for comparative interpretation. Additionally, based on the fault positions revealed in the geophysical profiles, a drilling joint profile was established across the fault, and Quaternary sediments were sampled and dated. The findings indicate that the f2 fault corresponds to the main fault of the Xiangfan-Guangji Fault in the Wuhan segment, while the f1 fault represents a secondary fault. Notably, the fault exhibited significant activity during the Middle Pleistocene of the Quaternary. These results provide new evidence for understanding the near-surface characteristics and activity of the Wuhan segment, offering valuable data for analyzing the fault's structure and evolution, as well as serving as a reference for seismic fortification in major urban engineering projects. This research holds significant value and potential for broader application.