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Microplastics (MP) are defined as synthetic organic pollutants sized <5 mm and have been recorded in various environments worldwide. Due to their small size, they pose a potential risk for many organisms throughout the food web. However, little is known about MP distribution patterns and associated transport mechanisms. Rivers may act as pathways for MP into marine environments. In this study, we investigate the occurrence of MP in the estuary and lower stretch of the second-largest German River, the Weser, representative of a significant interface between fresh water and marine environments. The aim of the study was to enhance the general understanding by providing novel, comprehensive data and suggestions for future studies on estuarine systems. Surface water samples of two different size classes were collected by ship using an on-board filtration system (11-500 μm fraction) and net sampling (500-5000 μm fraction). After a thorough sample preparation, all samples were analysed with Focal Plane Array (FPA) Fourier Transform Infrared (FTIR) spectroscopy and Attenuated Total Reflection (ATR) FTIR spectroscopy in order to obtain information on MP concentrations, polymer composition and size distribution. Our findings show highest concentrations in the 11-500 μm fraction (2.3 × 10 1  - 9.7 × 10 3  MP m -3 ), with the polymer cluster acrylates/polyurethanes(PUR)/varnish being dominant. The >500 μm fraction was dominated by polyethylene. Estimated MP concentrations generally increased in the Turbidity Maximum Zone (TMZ) and decreased towards the open sea. This study contributes to the current research by providing novel insights into the MP pollution of the estuary and lower stretch of an important European river and provides implications for future MP monitoring measures., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

This study uses longitudinal data from the Norwegian Health Study linked with registry data (n = 13262) and the U.S. National Longitudinal Survey of Youth 1997 (n = 3604) to examine (1) whether adolescent health mediates the well-established relationship between socioeconomic background and successful high school completion, and (2) whether this mediated pathway of influence varies by national context. Adolescents from lower educated and lower income families reported poorer health, which negatively impacted their likelihood of graduating from high school. The partial mediational effect of adolescent health was stronger in the U.S. than in Norway. These results suggest that policies aimed at preventing high school dropout need to address adolescent health, in addition to the unequal opportunities derived from socioeconomic disadvantage., (Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Purpose: Although child poverty is recognized as a critical determinant of poor educational achievement in the United States, policy discussions on raising academic achievement rarely include the importance of the effects of poverty on the mental health of adolescents. This article examines the role of adolescent emotional well-being (indicators of depression) as a mediator of the effects of poverty on differences in educational achievement at the national and U.S. state levels., Methods: Differences in standardized adolescent academic achievement across 23 developed countries and 39 U.S. states were analyzed using path analytic techniques to test the hypothesis that indicators of adolescent emotional well-being mediate relations between child poverty rates and academic achievement., Results: Child poverty rates were related to both adolescent emotional well-being and educational achievement across both U.S. states and developed countries. Path analyses showed that the status of a country's or state's adolescent emotional well-being is a strong predictor of its educational achievement and that emotional well-being mediates the relationship between poverty and educational achievement., Conclusion: Policies designed to ameliorate the adverse effects of poverty on mental health are critical as they are likely to improve both average educational achievement and student emotional well-being. Attention to improving mental health care not only has the potential to reduce societal and individual costs directly related to health but also to reduce the indirect costs of poor educational achievement., (Copyright © 2011 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)