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This paper outlines a novel two-stage procedure for estimating medium-term (ca. 40 years) rates of overbank sedimentation on British lowland floodplains, and exploring the relationship between floodplain morphology, floodwater hydraulics and fine sediment storage. The first stage utilises a two-dimensional hydraulic model that solves the depth-averaged shallow water equations over a high resolution topographic grid. This model is used to predict distributed patterns of flow depth and velocity within floodplain reaches approximately 0.4–0.6 km in length for floods of varying magnitude. These hydraulic data are then used, in conjunction with a simple sediment transport and deposition model, to estimate rates and patterns of floodplain sedimentation. This procedure was applied to a series of eight sites on the floodplain of the River Culm, Devon, UK, with contrasting morphological characteristics (e.g., channel sinuosity, channel numbers and dimensions, bankfull discharge, floodplain width, etc). The hydraulic modelling procedure was validated using ground and oblique aerial photography of floodwater inundation patterns. Estimates of medium-term sedimentation derived from 137Cs analysis of floodplain sediment cores were used to calibrate the sediment deposition model. Results indicate that within-reach variability in sedimentation rates reflects small-scale topographic controls on local flow characteristics and sediment transport and deposition processes. In contrast, between-reach variations in total sediment storage are largely a product of downstream changes in gross valley floor morphology and flood frequency. Preliminary estimates of the total sediment flux to the floodplain of the River Culm for the basin as a whole are consistent with previous estimates and highlight the importance of floodplain sedimentation as a component of the overall catchment sediment budget. [ABSTRACT FROM AUTHOR]

Background: Chronic pain was associated with a higher risk of mental disorders (e.g., depression and anxiety). However, the role of 24-h movement behaviors in the association remains unclear., Methods: A total of 72,800 participants with accelerometer data and free of mental disorders from the UK Biobank were analyzed. The compositional mediation model and isotemporal substitution model were used to explore the associations between chronic pain, 24-h movement behaviors, and the incidence of overall mental disorders, depression, and anxiety., Results: With a median follow-up of 13.36 years, participants with chronic pain had a higher rate of incident overall mental disorders (hazard ratio (HR): 1.281, 95% confidence interval (CI): 1.219 to 1.344), anxiety (HR: 1.391, 95% CI: 1.280 to 1.536), and depression (HR: 1.703, 95% CI: 1.551 to 1.871). Increased sedentary behavior (SB) and reduced moderate-to-vigorous physical activity (MVPA) caused by chronic pain both increased the risk of mental disorders. Twenty-four-hour movement behaviors explained the relationship between chronic pain and overall mental disorders, depression, and anxiety by 10.77%, 5.70%, and 6.86%, respectively. Interaction effects were found between MVPA and chronic pain when predicting the incidence of depression and between MVPA, sleep (SLP), and chronic pain when predicting the incidence of mental disorders. People with chronic pain would recommend at least 0.5 h per day of MVPA and 7 h per day of SLP and restricting SB below 11.5 h per day., Conclusions: Twenty-four-hour movement behaviors played a significant mediating role in the association between chronic pain and mental disorders. Individuals with chronic pain should engage in more MVPA, less sedentary behavior, and have 7-h sleep per day., (© 2024. The Author(s).)

In observational studies of children and adolescents, higher body weight has been associated with distinct disease outcomes, including cancer, in adulthood. Therefore, we performed a two-sample Mendelian randomization (MR) study to evaluate the causal effect of childhood obesity on long-term cancer risk. Single-nucleotide polymorphisms associated with higher childhood body mass index (BMI) from large-scale genome-wide association studies were used as genetic instruments. Summary-level data for 24 site-specific cancers were obtained from UK Biobank. We found that a 1-SD increase in childhood BMI (kg/m 2 ) was significantly associated with a 60% increase in risk of pancreatic cancer (odds ratio [OR]: 1.60; 95% confidence interval [CI]: 1.12-2.28; P < 0.01) and a 47% increase in risk of esophageal cancer (OR: 1.47; 95% CI: 1.09-1.97; P < 0.01) in adults. In contrast, there was an inverse association of genetic predisposition to childhood obesity with throat (OR: 0.46; 95% CI: 0.27-0.79; P < 0.01) and breast cancer (OR: 0.77; 95% CI: 0.64-0.94; P < 0.01) in adult life. For the other 20 cancers studied, no statistically significant association was observed. Our MR analyses found causal effects of childhood obesity on several cancers. Maintaining a healthy weight should be emphasized during childhood and adolescence to prevent cancer risk later in life., (© 2021 UICC.)