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To improve water quality and reduce instream erosion, floodplain remediation along agricultural streams can provide multiple ecosystem services through biogeochemical and fluvial processes. During floodplain inundation, longer water residence time and periodic anoxic conditions can lead to increased nitrogen (N) removal through denitrification but also mobilization of phosphorus (P), impeding overall water quality improvements. To investigate the capacity for N and P processing in remediated streams, we measured potential denitrification and nitrous oxide production and yields together with potential P desorption and P fractions in floodplain and stream sediments in ten catchments in Sweden. Sediment P desorption was measured as equilibrium P concentration, using P isotherm incubations. Denitrification rates were measured with the acetylene inhibition method. Sediment nutrient process rates were combined with hydrochemical monitoring along remediated streams and their paired upstream control reaches of trapezoidal shape to determine the impact of floodplains on water quality. The correlation between floodplain denitrification rates and P desorption (r = 0.53, p = 0.02) revealed a trade-off between soluble reactive P (SRP) and nitrate removal, driven by stream water connectivity to floodplains. Nitrous oxide production was not affected by differences in P processing, but nitrous oxide yields decreased with higher denitrification and P desorption. The release of SRP from floodplains (0.03 ± 0.41 mg P kg - 1 day - 1) was significantly lower than from trapezoidal stream banks (0.38 ± 0.37 mg P kg - 1 day - 1), predicted by long-term SRP concentrations in stream water and floodplain inundation frequency. The overall impact of SRP release from floodplains on stream SRP concentrations in remediated reaches was limited. However, the remediated reaches showing increased stream SRP concentrations were also frequently inundated and had higher labile P content and coarse soil texture in floodplain sediments. To fully realize the potential for water quality improvements with constructed floodplains in agricultural streams, the promotion of denitrification through increased inundation should be balanced against the risk of P release from sediments, particularly in streams with high SRP inputs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Agricultural headwaters are positioned at the interface between terrestrial and aquatic ecosystems and, therefore, at the margins of scientific disciplines. They are deemed devoid of biodiversity and too polluted by ecologists, overlooked by hydrologists, and are perceived as a nuisance by landowners and water authorities. While agricultural streams are widespread and represent a major habitat in terms of stream length, they remain understudied and thereby undervalued. Agricultural headwater streams are significantly modified and polluted but at the same time are the critical linkages among land, air, and water ecosystems. They exhibit the largest variation in streamflow, water quality, and greenhouse gas emission with cascading effects on the entire stream networks, yet they are underrepresented in monitoring, remediation, and restoration. Therefore, we call for more intense efforts to characterize and understand the inherent variability and sensitivity of these ecosystems to global change drivers through scientific and regulatory monitoring and to improve their ecosystem conditions and functions through purposeful and evidence-based remediation.

High-frequency water quality measurements in streams and rivers have expanded in scope and sophistication during the last two decades. Existing technology allows in situ automated measurements of water quality constituents, including both solutes and particulates, at unprecedented frequencies from seconds to subdaily sampling intervals. This detailed chemical information can be combined with measurements of hydrological and biogeochemical processes, bringing new insights into the sources, transport pathways, and transformation processes of solutes and particulates in complex catchments and along the aquatic continuum. Here, we summarize established and emerging high-frequency water quality technologies, outline key high-frequency hydrochemical data sets, and review scientific advances in key focus areas enabled by the rapid development of high-frequency water quality measurements in streams and rivers. Finally, we discuss future directions and challenges for using high-frequency water quality measurements to bridge scientific and management gaps by promoting a holistic understanding of freshwater systems and catchment status, health, and function.

Introduction: The National Center for Advancing Translational Sciences (NCATS) focuses on reducing barriers to effective translational research that rapidly translates science to clinical and community interventions to improve individual and community health. Community-Engaged Research (CEnR) plays a crucial role in this process by bridging gaps between research and practice. It effectively generates bi-directional knowledge and communication by engaging patients and communities throughout the translation research process. Skills development, however, is critical to enable investigators and communities to establish successful partnerships in research. While there are many independent CEnR education programs nationally, few curricula are mapped to identified domains and competencies., Assessment of Current Community Engagement Educational Frameworks and Competencies: We located three comprehensive efforts to identify CEnR domains and competencies that we aligned to inform development of our curriculum, which we then mapped to these competencies. The first, undertaken by the NCATS Joint Workgroup on Researcher Training and Education and Community Capacity Building (JWG) was developed to assess training opportunities for academic researchers and community partners to increase their capacity to meaningfully engage collaborators in translational research. The JWG identified curricula, resources, tools, strategies, and models for innovative training programs and community engagement in all stages of research. It also conducted a gap analysis of deficiencies in available resources. Using Competency Mapping, they developed a framework for curriculum mapping that included eight domains, each with two to five competencies of knowledge, attitudes, and skills. The second aligned community-engaged research competencies with online training resources across the CTSA consortium, while the third was focused on Dissemination and Implementation training., Actionable Recommendations: Further informed by a conceptual model to advance health equity, we have adapted and integrated these components into a set of modules designed to educate and empower investigators, trainees, students, and community partners to engage in effective CEnR., Discussion: This curriculum fills an important gap in our workforce development and helps to meet needs of our community partners. Following program evaluation and validation, we will offer the curriculum for use and further evaluation by other groups interested in using or adapting it for their own programming., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Hallmark, Bohn, Hallberg and Croisant.)

Heavily modified headwater streams and open ditches carry high nitrogen loads from agricultural soils that sustain eutrophication and poor water quality in downstream aquatic ecosystems. To remediate agricultural streams and reduce the export of nitrate (NO 3 - ), phosphorus and suspended sediments, two-stage ditches with constructed floodplains can be implemented as countermeasures. By extending hydrological connectivity between the stream channel and riparian corridor within constructed floodplains, these remediated ditches enhance the removal of NO 3 - via the microbial denitrification process. Ten remediated ditches were paired with upstream trapezoidal ditches in Sweden across different soils and land uses to measure the capacity for denitrification and nitrous oxide (N 2 O) production and yields under denitrifying conditions in stream and floodplain sediments. To examine the controls for denitrification, water quality was monitored monthly and flow discharge continuously along reaches. Floodplain sediments accounted for 33 % of total denitrification capacity of remediated ditches, primarily controlled by inundation and stream NO 3 - concentrations. Despite reductions in flow-weighted NO 3 - concentrations along reaches, NO 3 - removal in remediated ditches via denitrification can be masked by inputs of NO 3 - -rich groundwaters, typical of intensively managed agricultural landscapes. Although N 2 O production rates were 50 % lower in floodplains compared to the stream, remediated ditches emitted more N 2 O than conventional trapezoidal ditches. Higher denitrification rates and reductions of N 2 O proportions were predicted by catchments with loamy soils, higher proportions of agricultural land use and lower floodplain elevations. For realizing enhanced NO 3 - removal from floodplains and avoiding increased N 2 O emissions, soil type, land use and the design of floodplains need to be considered when implementing remediated streams. Further, we stress the need for assessing the impact of stream remediation in the context of broader catchment processes, to determine the overall potential for improving water quality., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personalrelationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Objective: Vertical transmission of hepatitis C virus (HCV) infection is uncommon and occurs in approximately 5% of births from HCV-infected mothers. The reason for the low transmission rate is unclear. We aimed to investigate whether there is evidence of HCV exposure also in the noninfected children born to HCV-infected mothers by the presence of a detectable immune response., Methods: Serum and peripheral blood mononuclear cells from 9 HCV vertically infected children, 32 uninfected children born to HCV infected mothers, and 15 HCV chronically infected mothers, were analyzed. HCV-RNA-negative adults and children were used as controls. HCV-specific T cell responses were analyzed by interferon gamma using an enzyme-linked immunospot assay and 3H-thymidine incorporation assay. HCV antibodies were also analyzed., Results: An HCV-specific T cell response was detected in 73% (11/15) of the HCV-infected mothers, 67% (6/9) of the vertically infected children, 56% (18/32) of the exposed but uninfected children and in 10% and 20% of the control groups, respectively. The 2 groups of HCV-exposed children both had a significantly higher proportion of HCV-specific T cell responders compared to pediatric controls (P = 0.01 and P = 0.02)., Conclusions: HCV-specific immune responses were more common in children born to HCV-infected mothers, regardless of the presence of HCV RNA. We conclude that noninfected children born to HCV-infected mothers may have been exposed to HCV antigens.

The aims of the study were to investigate healthy subjects' performance on a clinical test of high-level language (HLL) and how it is related to demographic characteristics and verbal working memory (VWM). One hundred healthy subjects (20-79 years old) were assessed with the Swedish BeSS test (Laakso, Brunnegård, Hartelius, & Ahlsén, 2000) and two digit span tasks. Relationships between the demographic variables, VWM and BeSS were investigated both with bivariate correlations and multiple regression analysis. The results present the norms for BeSS. The correlations and multiple regression analysis show that demographic variables had limited influence on test performance. Measures of VWM were moderately related to total BeSS score and weakly to moderately correlated with five of the seven subtests. To conclude, education has an influence on the test as a whole but measures of VWM stood out as the most robust predictor of HLL.