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Through emission processes, palladium (Pd) particulates from industrial sources are introduced into a range of ecosystems including freshwater environments. Despite this, research on Pd‐induced bioaccumulation, uptake, and toxicity is limited for freshwater fishes. Unlike other metals, there are currently no regulations or protective guidelines to limit Pd release into aquatic systems, indicating a global absence of measures addressing its environmental impact. To assess the olfactory toxicity potential of Pd, the present study aimed to explore Pd accumulation in olfactory tissues, olfactory disruption, and oxidative stress in rainbow trout (Oncorhynchus mykiss) following waterborne Pd exposure. Olfactory sensitivity, measured by electro‐olfactography, demonstrated that Pd inhibits multiple pathways of the olfactory system following 96 h of Pd exposure. In this study, the concentrations of Pd for inhibition of olfactory function by 20% (2.5 μg/L; IC20) and 50% (19 μg/L; IC50) were established. Rainbow trout were then exposed to IC20 and IC50 Pd concentrations in combination with varying exposure conditions, as changes in water quality alter the toxicity of metals. Independent to Pd, increased water hardness resulted in decreased olfactory perception owing to ion competition at the olfactory epithelium. No other environmental parameter in this study significantly influenced Pd‐induced olfactory toxicity. Membrane‐associated Pd was measured at the olfactory rosette and gill following exposure; however, this accumulation did not translate to oxidative stress as measured by the production of malondialdehyde. Our data suggest that Pd is toxic to rainbow trout via waterborne contamination near field‐measured levels. This study further demonstrated Pd bioavailability and uptake at water‐adjacent tissues, adding to our collective understanding of the toxicological profile of Pd. Taken together, our results provide novel insights into the olfactory toxicity in fish following Pd exposure. Integr Environ Assess Manag 2024;20:1407–1419. © 2024 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Key Points: Palladium (Pd) inhibits multiple fish olfaction pathways. Shifts in water quality did not alter Pd olfactory inhibition. [ABSTRACT FROM AUTHOR]

To explore clients’ and clinicians’ perspectives about the acceptability and perceived outcomes of the Sustaining New South Wales (NSW) Families (SNF) program shifted to a hybrid service delivery model during the COVID‐19 pandemic.Mixed methods design comprising cross‐sectional online surveys and a focus group.Eighty clients who accessed the SNF service and 12 SNF clinicians.Anonymous client survey comprising questions about perceived benefits and impacts of the hybrid SNF program model, and suggestions for change. Clinician focus group discussion about perceived benefits and challenges of the hybrid SNF model.The hybrid SNF program is a child and family health nursing home visitation program for families with moderate level psychosocial risks. It comprises a mix of face‐to‐face and virtual telehealth/telephone appointments, delivered during pregnancy and up to 2 years postpartum.Clients reported high levels of satisfaction with the program, and improvements in confidence and decision‐making. Clinicians spoke of increased efficiency and flexibility, and capacity for ongoing service provision during the COVID‐19 period. Technology access issues were identified as a barrier. Overall, however, both clients and clinicians expressed a preference for face‐to‐face SNF service provision.While further studies are required to test clinical outcomes, the hybrid SNF model is acceptable to clients and clinicians. [ABSTRACT FROM AUTHOR]

River organic matter transformations impact the cycling of energy, carbon, and nutrients. The delivery of distinct dissolved organic matter (DOM) sources can alter aquatic DOM cycling and associated biogeochemical processes. Yet DOM source and reactivity are not well‐defined for many river systems, including in western Canada. Here, we explore DOM cycling in the mainstem of the Oldman River (stream order 6–7), a heavily regulated river network in southern Alberta (Canada). We compared seasonal river DOM content, composition, and bioavailability with nine endmember leachates from the river valley using optical properties and incubations to estimate biodegradable dissolved organic carbon (BDOC). River DOM composition was most similar to terrestrial soil leachates, followed by autochthonous DOM leachates. River DOM bioavailability was low (BDOC = 0%–16.6%, mean of 7.1%). Endmember leachate bioavailability increased from soils (BDOC = 23.9%–53.7%), to autochthonous sources (fish excretion, macrophytes, biofilm; BDOC = 49.9%–80.0%), to terrestrial vegetation (leaves, shrubs, grass; BDOC > 80%), scaling positively with protein‐like DOM content and amount of leachable dissolved organic carbon (DOC), and negatively with aromaticity. Seasonally, DOC concentrations changed little despite >15‐fold increases in discharge during spring. River DOM composition shifted modestly toward soil‐like endmembers in spring and more bioavailable autochthonous end members in autumn and winter. Low DOM bioavailability in the river mainstem and low DOC yields shown in previous work point to limited internal processing of DOM and limited bioavailable DOM delivery to downstream habitats, possibly due to upstream flow regulation. Our observations provide important insights into the functioning of western Canadian aquatic networks. Plain Language Summary: Rivers are among the most heavily disturbed ecosystems worldwide. In agricultural regions of western Canada, human impacts on river ecosystem structure and functioning are not well defined. The study of organic matter chemistry provides important insights into aquatic ecosystem properties and biogeochemical processes. Here, we explore the seasonal trends in composition and content of dissolved organic matter in one of Canada's most heavily regulated rivers (the Oldman River, Alberta). While land use impacts on river organic matter cycling are documented elsewhere, we provide unique insights by tracking changes in river organic matter composition and microbial consumption across a complete annual cycle that includes winter. The composition and content of river organic matter changed little among seasons. Compared to potential organic matter sources from the river valley (soils, plants, aquatic organisms, and biofilm), river water had organic matter that mostly resembled soil sources, and secondarily river sources. Compared to all potential sources, river organic matter was less bioavailable to microbes and on the low end of bioavailability relative to other global aquatic systems. We hypothesize that human alterations to the flow regime upstream (including damming and irrigation) may dampen seasonal changes in river organic matter composition and cycling. Key Points: Bioavailability of end member leachates increased from soils to river sources (fish, then macrophytes and biofilm), to terrestrial plantsDissolved organic matter (DOM) composition and bioavailability were modestly responsive to elevated discharge during the spring freshetWeakly bioavailable soil DOM dominated the downstream river pool, possibly showing the mainstem is not a hotspot for DOM transformation [ABSTRACT FROM AUTHOR]

Bioremediation of crude‐oil‐contaminated soils is critical to supporting soil ecosystem health and functioning. Here, to explore the potential for different remediation strategies to restore soil microbial functioning and enhance remediation, three strains of bacteria, Bacillus toyonensis, Bacillus sp. and Bacillus cereus, were inoculated to saline, crude oil‐contaminated soil collected from Azadegan Oil Field, Iran. Bacteria were added using different carriers, including corn biochar, humic acid, chitosan and kaolin, and free bacteria as a control. Changes in soil metal concentrations and residual crude oil were determined after 60 days of incubation. Soil respiration, microbial biomass, and enzyme (dehydrogenase and catalase) activities were measured. The carriers accompanying a bacterial consortium were more efficient than free bacteria in removing crude oil and heavy metals from soil, and they performed better in removing n‐alkanes with carbon chains of C12–24. The oil removal rate and metal immobilization efficiencies were greatest in soils with chitosan‐bacteria treatment, with removal of crude oil, Al, Pb, Sr, and Cr (93%, 63%, 37%, 54%, and 15%, respectively) greater than for soils with free cells without treatment (61%, 54%, 9%, 50%, and 3%, respectively). Soil electrical conductivity decreased after application of bacterial mixtures with and without carriers. The inoculation of bacteria and application of soil amendments increased soil microbial biomass carbon and the activity of catalase and dehydrogenase. Overall, our results indicated the greatest potential remediation was achieved by applying immobilized microorganisms in chitosan to accelerate the biodegradation of crude oil and the removal of heavy metals. Plain Language Summary: Crude oil pollution can affect soil health by impairing the functioning of the microbial community. Bioremediation of contaminated soils using microorganisms that can break down crude oil shows great potential, but this is an emerging applied practice, and more research is needed to understand the optimal conditions to stimulate microbial metabolism and remediation. In particular, the degradation potential can be enhanced by inoculating soils using carriers that provide a suitable habitat for microbes, protecting them from adverse conditions and improving their ability to degrade contaminants. In this study three bacterial strains were isolated from crude‐oil‐contaminated soil, and then inoculated in saline contaminated soils using different carriers (corn biochar, humic acid, chitosan, and kaolin) and a free bacterial control. We measured total crude oil hydrocarbon removal and basic soil properties including soil respiration, microbial biomass and enzyme activities. Immobilization of bacteria in chitosan showed the greatest effect, enhancing the removal of crude oil and heavy metals, especially Pb and Cr. This treatment enhanced soil community metabolism and reduced electrical conductivity of soil, and therefore holds great potential to improve soil health and community functioning in similar contaminated ecosystems. Key Points: The applied carriers indicated different efficiencies to remove TPHs and heavy metals from soilChitosan was an effective carrier for immobilization of bacteria, removal of TPHs, and some heavy metals from saline soilThe inoculation of bacteria and application of carriers altered soil biological and chemical properties [ABSTRACT FROM AUTHOR]

Conspiratorial thinking has been with humanity for a long time but has recently grown as a source of societal concern and as a subject of research in the cognitive and social sciences. We propose a three‐tiered framework for the study of conspiracy theories: (1) cognitive processes, (2) the individual, and (3) social processes and communities of knowledge. At the level of cognitive processes, we identify explanatory coherence and faulty belief updating as critical ideas. At the level of the community of knowledge, we explore how conspiracy communities facilitate false belief by promoting a contagious sense of understanding, and how community norms catalyze the biased assimilation of evidence. We review recent research on conspiracy theories and explain how conspiratorial thinking emerges from the interaction of individual and group processes. As a case study, we describe observations the first author made while attending the Flat Earth International Conference, a meeting of conspiracy theorists who believe the Earth is flat. Rather than treating conspiracy belief as pathological, we take the perspective that is an extreme outcome of common cognitive processes. We propose a three‐tiered framework for the study of conspiracy theories: (1) cognitive processes, (2) the individual, and (3) social processes and communities of knowledge. We review recent research on conspiracy theories and explain how conspiratorial thinking emerges from the interaction of individual and group processes. As a case study, we describe observations the first author made while attending the Flat Earth International Conference, a meeting of conspiracy theorists who believe the Earth is flat. [ABSTRACT FROM AUTHOR]

The Arctic is the fastest warming biome on the planet, and environmental changes are having striking effects on freshwater ecosystems that may impact the regional carbon cycle. The metabolic state of Arctic lakes is often considered net heterotrophic, due to an assumed supply of allochthonous organic matter that supports ecosystem respiration and carbon mineralization in excess of rates of primary production. However, lake metabolic patterns vary according to regional climatic characteristics, hydrological connectivity, organic matter sources and intrinsic lake properties, and the metabolism of most Arctic lakes is unknown. We sampled 35 waterbodies along a connectivity gradient from headwater to downstream lakes, on southern Victoria Island, Nunavut, in an area characterized by low precipitation, organic‐poor soils, and high evaporation rates. We evaluated whether lakes were net autotrophic or heterotrophic during the open water period using an oxygen isotopic mass balance approach. Most of the waterbodies were autotrophic and sites of net organic matter production or close to metabolic equilibrium. Autotrophy was associated with higher benthic primary production, as compared to its pelagic counterpart, due to the high irradiance reaching the bottom and efficient internal carbon and nutrient cycling. Highly connected midstream and downstream lakes showed efficient organic matter cycling, as evidenced by the strong coupling between gross primary production (GPP) and ecosystem respiration, while decoupling was observed in some headwater lakes with significantly higher GPP. The shallow nature of lakes in the flat, arid region of southern Victoria Island supports net autotrophy in most lakes during the open water season. Ongoing climate changes that lengthen the ice‐free irradiance period and increase rates of nutrient evapoconcentration may further promote net autotrophy, with uncertain long‐term effects for lake functioning. [ABSTRACT FROM AUTHOR]

Key points Breathing mild bouts of low oxygen air (i.e. acute intermittent hypoxia, AIH) has been shown to improve locomotor function in humans after a spinal cord injury. How AIH‐induced gains in motor performance are achieved remains unclear. We examined the hypothesis that AIH augments motor learning and motor retention during a locomotor adaptation task. We further hypothesized that gains in motor learning and retention will be associated with reductions in net metabolic power, consistent with the acquisition of energetically favourable mechanics. Thirty healthy individuals were randomly allocated into either a control group or an AIH group. We utilized a split‐belt treadmill to characterize adaptations to an unexpected belt speed perturbation of equal magnitude during an initial exposure and a second exposure. Adaptation was characterized by changes in spatiotemporal step asymmetry, anterior–posterior force asymmetry, and net metabolic power. While both groups adapted by reducing spatial asymmetry, only the AIH group achieved significant reductions in double support time asymmetry and propulsive force asymmetry during both the initial and the second exposures to the belt speed perturbation. Net metabolic power was also significantly lower in the AIH group, with significant reductions from the initial perturbation exposure to the second. These results provide the first evidence that AIH mediates improvements in both motor learning and retention. Further, our results suggest that reductions in net metabolic power continue to be optimized upon subsequent learning and are driven by more energetically favourable temporal coordination strategies. Our observation that AIH facilitates motor learning and retention can be leveraged to design rehabilitation interventions that promote functional recovery. Brief exposures to low oxygen air, known as acute intermittent hypoxia (AIH), improves locomotor function in humans after a spinal cord injury, but it remains unclear how gains in motor performance are achieved. In this study, we tested the hypothesis that AIH induces enhancements in motor learning and retention by quantifying changes in interlimb coordination, anterior–posterior force symmetry and metabolic cost during a locomotor adaptation task. We show the first evidence that AIH improves both motor learning and savings of newly learned temporal interlimb coordination strategies and force asymmetry compared to untreated individuals. We further demonstrate that AIH elicits greater reductions in metabolic cost during motor learning that continues to be optimized upon subsequent learning. Our findings suggest that AIH‐induced gains in locomotor performance are facilitated by enhancements in motor learning and retention of more energetically favourable coordination strategies. [ABSTRACT FROM AUTHOR]

Co-production practices are increasingly being adopted in research conducted for the purpose of societal impact. However, the ways in which co-production is conducted can perpetuate long-standing inequity and inequality. This study investigates which principles of co-production design are perceived to advance more equitable processes and outcomes based on the experiences of participants in three projects funded by U.S. federal programs that support decision-relevant climate science, along with others engaged in co-production efforts. We found three distinct perspectives: (a) Ways of Knowing and Power; (b) Participants and Interactions; and (c) Science as Capacity Building. Each viewpoint differentially weights the salience of statements associated with five dimensions of co-production practices: (a) outcomes; (b) power; (c) place-based, community rights and respect; (d) audiences and participation; and (e) interactions. In the final stage of the study, we hosted a workshop of participants representing various roles in co-production efforts to vet and discuss each perspective. We found that the perspectives remained distinct after each of the groups selected core statements that reflect their views. The degree of variation across the three perspectives suggests that co-production processes would benefit from an initial discussion of, and decisions about, rules of engagement to ensure that participants view the process as equitable. [ABSTRACT FROM AUTHOR]

Background and Purpose: T‐type calcium channels, mainly the Cav3.2 subtype, are important contributors to the nociceptive signalling pathway. We investigated their involvement in inflammation and related pain‐like symptoms. Experimental Approach: The involvement of Cav3.2 and T‐type channels was investigated using genetic and pharmacological inhibition to assess mechanical allodynia/hyperalgesia and oedema development in two murine inflammatory pain models. The location of Cav3.2 channels involved in pain‐like symptoms was studied in mice with Cav3.2 knocked out in C‐low threshold mechanoreceptors (C‐LTMR) and the use of ABT‐639, a peripherally restricted T‐type channel inhibitor. The anti‐oedema effect of Cav3.2 channel inhibition was investigated in chimeric mice with immune cells deleted for Cav3.2. Lymphocytes and macrophages from either green fluorescent protein‐targeted Cav3.2 or KO mice were used to determine the expression of Cav3.2 protein and the functional status of the cells. Key Results: Cav3.2 channels contributed to the development of pain‐like symptoms and oedema in the two murine inflammatory pain models. Our results provided evidence of the involvement of Cav3.2 channels located on C‐LTMRs and spinal cord in inflammatory pain. Cav3.2 channels located in T cells and macrophages contribute to the inflammatory process. Conclusion and Implications: Cav3.2 channels play crucial roles in inflammation and related pain, implying that targeting of Cav3.2 channels with pharmacological agents could be an attractive and readily evaluable strategy in clinical trials, to relieve chronic inflammatory pain in patients. [ABSTRACT FROM AUTHOR]

This article examines the nature of student‐to‐student text discussion in a dialogically organized remote classroom. Conducted as teacher research, I investigated student talk in a PreK‐1st grade biblical literature class. In the fall of 2020, I taught a biblical literature class to a fully remote PreK‐1st grade cohort in a Jewish independent school on the East Coast. Four undergraduate research assistants from the SCRoLL education lab helped with ongoing data analysis. Through self‐study of my teaching and classroom, I discovered the ways that the remote setting shaped intensive text discussion, facilitating students' comfort stepping into their own interpretive authority and moving past the classroom fixture of teacher as interpretive authority. In the remote classroom, the students comfortably moved between the first conversation, the meaning of the text, and the second conversation, competing conventions for determining the meaning of the text. I conclude with suggestions for how teachers interested in dialogically organized classrooms can carry the assets of the remote classroom forward. [ABSTRACT FROM AUTHOR]

Climate change is thawing and potentially mobilizing vast quantities of organic carbon (OC) previously stored for millennia in permafrost soils of northern circumpolar landscapes. Climate‐driven increases in fire and thermokarst may play a key role in OC mobilization by thawing permafrost and promoting transport of OC. Yet, the extent of OC mobilization and mechanisms controlling terrestrial‐aquatic transfer are unclear. We demonstrate that hydrologic transport of soil dissolved OC (DOC) from the active layer and thawing permafrost to headwater streams is extremely heterogeneous and regulated by the interactions of soils, seasonal thaw, fire, and thermokarst. Repeated sampling of streams in eight headwater catchments of interior Alaska showed that the mean age of DOC for each stream ranges widely from modern to ∼2,000 years B.P. Together, an endmember mixing model and nonlinear, generalized additive models demonstrated that Δ14C‐DOC signature (and mean age) increased from spring to fall, and was proportional to hydrologic contributions from a solute‐rich water source, related to presumed deeper flow paths found predominantly in silty catchments. This relationship was correlated with and mediated by catchment properties. Mean DOC ages were older in catchments with >50% burned area, indicating that fire is also an important explanatory variable. These observations underscore the high heterogeneity in aged C export and difficulty of extrapolating estimates of permafrost‐derived DOC export from watersheds to larger scales. Our results provide the foundation for developing a conceptual model of permafrost DOC export necessary for advancing understanding and prediction of land‐water C exchange in changing boreal landscapes. Plain Language Summary: In high latitude environments, soils that have been frozen for millennia are thawing, releasing organic carbon (OC). Thawing and export of OC to downstream aquatic ecosystems is a potential biogeochemical feedback that may accelerate climate warming if large amounts of ancient OC are transformed and released to the atmosphere as greenhouse gases. The magnitude and timing of ancient OC thaw and mobilization are not well defined, so predicting these patterns at local to global scales is challenging. Using a suite of diverse headwater catchments in the discontinuous permafrost zone of Alaska, USA, we identify the main controls on the mobilization of ancient OC from thawing landscapes into adjacent streams. Our surveys show that ancient OC export depends on the complex interaction between fire history, soil type and thawing characteristics, and seasonal warming. We find that all of these factors play a role, resulting in highly heterogeneous release of ancient OC to headwater streams. Key Points: Aged dissolved organic carbon (DOC) in headwater streams in interior Alaska is heterogeneous across permafrost landscapes indicating the interplay of multiple driversAged DOC concentrations increase from spring to fall and are highest in catchments with >50% burned extent and dominated by silty uplandsAged DOC is proportional to stream solute loads, indicating that deeper flow paths deliver permafrost C to streams [ABSTRACT FROM AUTHOR]

Grasslands are among the most disturbed systems on Earth due to extensive agricultural development and river regulation. To define how these factors impact the movement of carbon (C) through river networks, we quantified multi‐decadal, seasonal patterns of dissolved organic C (DOC) fluxes through a grassland river network. Despite urbanization and effluent release in recent decades, we did not observe trends in DOC fluxes over 20 to 40 year monthly sample records. High interannual variability in DOC flux was linked to climate teleconnections, most strongly the Pacific Decadal Oscillation. Human impacts were more apparent on the seasonality of flux, since spring export dominated DOC flux in most sub‐watersheds, but seasonal changes were absent at the river mouth due to downstream flow control. In grassland regions, human impacts on DOC flux are complex, and subtle long‐term changes may be difficult to identify in contemporary monitoring records due to increasing hydro‐climatic variability. Plain Language Summary: Grasslands are extensively used by humans with approximately 90% of lands converted for human uses globally. However, it is unclear how these changes impact river carbon cycling and fluxes because long records of discharge and dissolved organic carbon (DOC) are uncommon. Here we used 20–40 years of publicly available data to investigate the patterns and controls of DOC flux, the amount of DOC that flows downstream, in a mountain to grassland transitional river network. Water and DOC fluxes had extreme variability among years and across sites. Mountain, headwater sites with more forest land cover exported more DOC for a given unit of watershed area, while prairie sites with high grassland and agricultural land cover had lower DOC yields. The bulk of DOC mobilized through these rivers occurred during the spring snowmelt period, except downstream where a large reservoir system dampened seasonal DOC fluxes. While we did not find any significant changes through time in DOC fluxes, variability appeared to be at least partially controlled by continental scale climate oscillations that drive regional temperature and precipitation patterns. Together, these results help to unravel the controls on riverine biogeochemistry and carbon cycling in an understudied, socio‐economically important ecoregion. Key Points: No directional temporal trends in dissolved organic carbon (DOC) flux but interannual variability was partly linked to climate oscillationsAn extensive reservoir complex represents an important disturbance to the seasonality and magnitude of DOC flux through the river networkMountain headwaters are a critical source of water and DOC to grassland rivers and sustain downstream ecosystems [ABSTRACT FROM AUTHOR]

Rivers and their adjacent riparian forests are intimately linked by the exchange of water, nutrients, and organic matter. Both riparian cottonwood trees and adjacent river sediments host microbial communities including archeal methanogens, supporting methane production and emission to the atmosphere. Here we combine microbial community and in vitro stable isotope analyses to characterize the drivers of methane cycling in distinct anoxic habitats (river sediments vs. riparian cottonwood stems) associated with the Oldman River, southern Alberta (Canada). We demonstrate that, differences in the chemical characteristics of organic matter support divergent microbial communities that generate methane from distinct metabolic pathways. Organic matter in river sediments had C/N ratios approximately 50‐fold lower than in tree stems and had more diverse dissolved organic components. Contrasting substrate availability between river sediment and tree stems was likely the primary mechanism for the greater microbial diversity in river sediments than in tree stems, the significantly different bacterial communities, and the trend toward differing abundance of methanogen orders. The methane carbon isotope composition (δ13C values) differed for the tree stem (−103.6‰ to −70.6‰) and river sediment (−55.1‰ to −48.4‰) environments, suggesting that methane was primarily produced via CO2‐reduction in tree stems by Methanobacteriales, while river sediments produced more methane through acetate fermentation primarily by Methanosarcinales. This study demonstrates the importance of organic matter quality and microbial community composition in driving metabolic processes contributing to methane production and emission in rivers and adjacent riparian forests. Plain Language Summary: In semi‐arid habitats, riparian trees are restricted to areas adjacent to flowing rivers. Some riparian tree stems and adjacent river sediments harbor microorganisms that produce methane that is released to the atmosphere. In this study we compared the microbial communities that exist in cottonwood riparian trees stems and the adjacent river sediment. Our results indicated that the bacterial communities and the methane‐producing archeal communities strongly differed between the tree stems and river sediment, likely because the organic matter in the two environments had contrasting chemical characteristics. As a consequence of the differences in the microbial communities and organic matter, the archeal microbes produce methane via different biochemical pathways that result in the methane released by the tree stems and river sediments having contrasting amounts of two stable isotopes of carbon (13C and 12C). This establishes the opportunity to identify and separate, based on its stable carbon isotope ratio, the methane that is released from tree stems and river sediment in these adjacent and linked terrestrial and aquatic ecosystems. Our study also provides greater understanding of factors controlling methane production in tree stems and river sediments, processes that are currently not included in global methane budgets. Key Points: Riparian cottonwood tree stems and the adjacent river sediments produce methane formed from the microbial breakdown of organic matterOrganic matter in river sediment was highly processed by decomposition and had more diverse microbial communities than those in tree stemsRiver sediments and tree stems with contrasting organic matter and microbial communities produced methane by different metabolic pathways [ABSTRACT FROM AUTHOR]

Deltoid tendon humeral sided avulsion leads to discomfort and functional limitation in the young active population. This report illustrates a case for surgical treatment with a simple suspensory device that allows for early return to activity. [ABSTRACT FROM AUTHOR]

Despite growing research on greenhouse gas (GHG) emissions from inland waters, few systematic efforts have been made to assess the regional‐scale GHG emissions from Asian rivers under increasing anthropogenic stress. We examined factors controlling longitudinal and seasonal variations in the partial pressure of CO2 (pCO2), and CH4 and N2O concentrations in the Ganges, Mekong, and Yellow River by simultaneously measuring gas concentrations and stable C isotopes, and optical properties of dissolved organic matter (DOM) from 2016 to 2019. The levels of pCO2 and CH4 were distinctively higher in polluted tributaries and affected reaches of the Ganges and Mekong than in the Yellow River. The highest levels of N2O were found in the Ganges, followed by the Yellow River and Mekong. Across these basins, dry‐season mean concentrations of CO2, CH4, and N2O were 1.6, 2, and 7 times higher than those measured in the monsoon season, respectively. This seasonality was consistent with that of δ13C‐CO2, while δ13C‐CH4 showed an opposite pattern. GHG concentrations exhibited significant positive relationships with DOM concentrations and optical properties including fluorescence index and protein‐like fluorescence, implying the contribution of anthropogenic, labile DOM to production of GHGs in the polluted reaches. Graphical mixing models of δ13C‐CO2 and δ13C‐CH4 support the stronger impact of wastewater on the Ganges and Mekong than on the Yellow River. The overall results suggest that neglecting localized pollution impacts on GHG emissions from increasingly urbanized river basins can result in a substantial underestimation of global riverine GHG emissions. Plain Language Summary: Rapid urbanization and poor wastewater infrastructure are turning many large rivers in Asia into significant sources of greenhouse gases (GHGs). We examined controlling factors for the concentrations of CO2, CH4, and N2O in the Ganges, Mekong, and Yellow River by simultaneously measuring gas concentrations and stable carbon isotopes, and optical properties of dissolved organic matter (DOM). The concentrations of CO2 and CH4 were distinctively higher in polluted tributaries and affected sections of the Ganges and Mekong than in the Yellow River. N2O concentration was highest in the Ganges, followed by the Yellow River and Mekong. Across these basins, the concentrations of the three gases were generally higher during dry periods than in the monsoon season. GHG concentrations were positively related to DOM optical properties indicating the contribution of easily degradable DOM from pollution sources. The stable carbon isotope ratios of CO2 and CH4 support the stronger impact of wastewater on the Ganges and Mekong than on the Yellow River. The overall results suggest that neglecting local pollution impacts on GHG emissions from increasingly urbanized river basins can result in a substantial underestimation of global riverine GHG emissions. Key Points: High CO2, CH4, and N2O concentrations in urbanized river reaches reflect influences from local tributaries carrying wastewaterSeasonality in stable C isotopes and dissolved organic matter properties corresponds to higher dry‐season greenhouse gas concentrations than in the monsoonStable C isotopes and their relationships with CO2 and CH4 concentrations support localized wastewater effects on urbanized rivers [ABSTRACT FROM AUTHOR]

Northern high‐latitude lakes are undergoing climate‐induced changes including shifts in their hydrologic connectivity with terrestrial ecosystems. How this will impact dissolved organic matter (DOM) biogeochemistry remains uncertain. We examined the drivers of DOM composition for lakes in the Yukon Flats Basin in Alaska, an arid region of low relief that is characteristic of over one‐quarter of circumpolar lake area. Utilizing the vascular plant biomarker lignin, chromophoric dissolved organic matter (CDOM), and ultrahigh‐resolution mass spectrometry, we interpreted DOM compositional changes using lake‐water stable isotope (δ18O‐H2O) composition as a proxy for lake hydrologic connectivity with the landscape. We observed a relative decrease in CDOM in more hydrologically isolated lakes (enriched δ18O‐H2O) without a corresponding decrease in dissolved organic carbon (DOC) concentration. Although DOC and CDOM were weakly correlated, a significant positive relationship between lignin and CDOM (r2 = 0.67) demonstrates that optical parameters are useful for estimating lignin concentration and thus vascular plant contribution to lake DOM. Indicators of allochthonous DOM, including lignin carbon normalized yields, CDOM aromaticity proxies, and relative abundances of polyphenolic and condensed aromatic compound classes, were negatively correlated with δ18O‐H2O (r2 > 0.45), suggesting there is little allochthonous DOM supplied to many of these hydrologically isolated lakes. We conclude that decreased lake hydrologic connectivity, driven by ongoing climate change (i.e., decreased precipitation, warming temperatures), will reduce allochthonous DOM contributions and shift lakes toward lower CDOM systems with ecosystem‐scale ramifications for heat transfer, photochemical reactions, productivity, and ultimately their biogeochemical function. [ABSTRACT FROM AUTHOR]

Coastal wetlands are among the most productive habitats on Earth and sequester globally significant amounts of atmospheric carbon (C). Extreme rates of soil C accumulation are widely assumed to reflect efficient C storage. Yet the fraction of wetland C lost via hydrologic export has not been directly quantified, since comprehensive budgets including direct estimates of lateral C loss are lacking. We present a complete net ecosystem C budget (NECB), demonstrating that lateral losses of C are a major component of the NECB for the largest stable brackish tidal marsh on the U.S. Pacific coast. Mean annual net ecosystem exchange of CO2 with the atmosphere (NEE = −185 g C m2 year−1, negative NEE denoting ecosystem uptake) was compared to long‐term soil C burial (87–110 g C m2 year−1), suggesting only 47–59% of fixed atmospheric C accumulates in soils. Consistently, direct monitoring in 2017–2018 showed NEE of −255 g C m−2 year−1, and hydrologic export of 105 g C m−2 year−1 (59% of NEE remaining on site). Despite their high C sequestration capacity, lateral losses from coastal wetlands are typically a larger fraction of the NECB when compared to other terrestrial ecosystems. Loss of inorganic C (the least measured NECB term) was 91% of hydrologic export and may be the most important term limiting C sequestration. The high productivity of coastal wetlands thus serves a dual function of C burial and estuarine export, and the multiple fates of fixed C must be considered when evaluating wetland capacity for C sequestration. Key Points: We present a complete carbon budget for the largest brackish tidal marsh in the Pacific United StatesDirect and indirect measurement showed 47% to 59% of fixed carbon is stored on site and most loss is through inorganic carbon exportA compilation of global data sets showed lateral loss larger term in coastal wetland carbon budgets, relative to other terrestrial systems [ABSTRACT FROM AUTHOR]

Scientific Significance Statement: Metabolic stoichiometry predicts that dissolved oxygen (O2) and carbon dioxide (CO2) in aquatic ecosystems should covary inversely; however, field observations often diverge from theoretical expectations. Here, we propose a suite of metrics describing this O2 and CO2 decoupling and introduce a conceptual framework for interpreting these metrics within aquatic ecosystems. Within this framework, we interpret cross‐system patterns of high‐frequency O2 and CO2 measurements in 11 northern lakes and extract emergent insights into the metabolic behavior and the simultaneous roles of chemical and physical forcing in shaping ecosystem processes. This approach leverages the power of high‐frequency paired O2–CO2 measurements, and yields a novel, integrative aquatic system typology which can also be applicable more broadly to streams and rivers, wetlands and marine systems. [ABSTRACT FROM AUTHOR]

Solomon Islands, like many Pacific Island nations, suffer from the burden of malnutrition. External drivers including population growth, declining agriculture and fisheries productivity and global food trade have contributed to the transition to greater reliance on imported foods. Globally, diets are recognized as both a cause of and solution to the burden of malnutrition. Using a mixed‐method approach this study assessed nutritional status and key determinants of malnutrition among women and young children in rural Solomon Island communities. Quantitative 24‐hour recall surveys identified diets of women and young children in these communities to be very limited in diversity. Typical daily diets comprised of fish, sweet potato (and/or rice) and slippery cabbage (a leafy green) usually boiled in coconut milk or baked. Participatory research using problem tree and biocultural approaches identified basic determinants of poor diets and opportunities to address these challenges. We highlight three domains of opportunity to improve diets across multiple scales; 1) improve nutrition‐sensitive agriculture and fisheries to produce and distribute diverse, productive and nutrient rich foods; 2) nutrition education and empowerment, focusing on the first 1000 days of life, to influence and inform choices regarding food consumption; and 3) reducing the consumption of imported, energy‐rich nutrient poor foods through national and regional policies. These multi‐scale domains highlight that food system approaches that strengthen integrated policy and empower people are essential for healthy and sustainable diets in Solomon Islands and more broadly in the Pacific region. [ABSTRACT FROM AUTHOR]

In Australian wheat (Triticum aestivum L.) production, optimizing wheat phenology is essential for yield potential and to avoid stress, especially around flowering. Breeding could be accelerated by identifying key loci and developing models to predict genotype flowering times under different pedoclimatic scenarios. Here, association genetics for heading date, earliness components (photoperiod sensitivity [PS]; vernalization requirement [VR]; earliness per se [EPS]) and simulation model (APSIM) phenology parameters from a panel of Australian cultivars and breeding lines identified loci with stable, repeatable effects. Major chromosomal regions with stable effects included the Ppd‐D1 region on chromosome 2D for PS and EPS, one region on 5B for PS, one region on 6B for EPS, and the Vrn‐A1 region on 5A for VR. Regions with stable, smaller effects were detected on 1A and 2D for PS, on 5A and 6B for EPS, and on 1A and 5D for VR. Other regions with stable effects on heading date and earliness components were located on 1A, 2B, 4B, 5B, 6B and 7B (PS and EPS), 2A, 3A and 7A (EPS and VR). Quantitative trait loci (QTL)–based model parameters were used to simulate heading dates across the Australian wheat belt for set of independent genotypes. Comparisons of average observed and predicted heading dates for four main regions of the Australian wheat belt showed good performance in prediction of independent lines from QTL information alone (r2 =.61–.83). The model allows testing of putative genotypes under various pedoclimatic scenarios including for adaptation to anticipated climate changes. [ABSTRACT FROM AUTHOR]

Wheat spindle streak mosaic virus (WSSMV) is a major concern for cereal crops in Europe and North America. A strong increase in the occurrence of WSSMV has been observed in each French region where susceptible cultivars are cultivated. Most European bread wheat cultivars are resistant, but assessing the status of newly registered cultivars or breeding lines regarding WSSMV resistance is of importance. This paper describes a genome‐wide association study carried out on a panel of 163 cultivars and tested for their resistance to WSSMV. Two regions on chromosomes 5B and 7D showed minor effects on WSSMV resistance. More importantly, a large genomic region on chromosome 2D explained most of the resistance to WSSMV. More than 99% of the cultivars carrying the AA genotype at the most associated marker (Excalibur_c15426_661) were resistant to WSSMV, while 100% of the cultivars showing the GG genotype were susceptible. This large genomic region of 45.8 Mb was found distal to the centromere and showed very high linkage disequilibrium. It is hypothesized that this region may be an alien introgression originating from a wild related species. This region contains a total of 2605 predicted genes based on the Chinese Spring IWGSC RefSeq v. 1.0 including genes potentially involved in plant disease resistance. A kompetitive allele‐specific PCR (KASP) single‐nucleotide polymorphism (SNP) marker was designed in order to identify breeding lines or registered cultivars resistant to WSSMV. [ABSTRACT FROM AUTHOR]

As overfertilization leads to environmental concerns and the cost of N fertilizer increases, the issue of how to select crop cultivars that can produce high yields on N‐deficient soils has become crucially important. However, little information is known about the genetic mechanisms by which crops respond to environmental changes induced by N signaling. Here, we dissected the genetic architecture of N‐induced phenotypic plasticity in bread wheat (Triticum aestivum L.) by integrating functional mapping and semiautomatic high‐throughput phenotyping data of yield‐related canopy architecture. We identified a set of quantitative trait loci (QTLs) that determined the pattern and magnitude of how wheat cultivars responded to low N stress from normal N supply throughout the wheat life cycle. This analysis highlighted the phenological landscape of genetic effects exerted by individual QTLs, as well as their interactions with N‐induced signals and with canopy measurement angles. This information may shed light on our mechanistic understanding of plant adaptation and provide valuable information for the breeding of N‐deficiency tolerant wheat varieties. Significance Statement: The integration of functional mapping and high‐throughput phenotyping shows holistic power to reveal the genetic architecture of how plants grow, develop, and respond to environmental changes. Its application to wheat genome‐wide association studies (GWAS) led to the identification of N‐deficiency‐activated QTLs involved in vegetation traits underlying canopy structure and function. [ABSTRACT FROM AUTHOR]

Objectives: Various methods of fetal‐fraction measurement have been employed in conjunction with different approaches to cell‐free DNA testing for fetal aneuploidy. In this study, we determined the accuracy and reproducibility of fetal‐fraction measurement using polymorphic assays that are incorporated into the test design as part of the Harmony® prenatal test and evaluated whether the single nucleotide polymorphisms selected for and used in these assays can be applied broadly to all patient populations. Methods: Clinical maternal plasma samples were assayed using a custom microarray with Digital ANalysis of Selected Regions (DANSR) assays designed to cover non‐polymorphic targets on chromosomes of interest for aneuploidy assessment (13, 18, 21, X and Y) and polymorphic targets for fetal‐fraction assessment. In a consecutive series of 47 512 maternal plasma samples, fetal‐fraction measurements based on polymorphic assays were compared with those from Y‐sequence quantitation. Reproducibility was examined between first‐ and second‐tube measurements for the same patient sample in 734 cases. The fraction of informative loci was calculated for 13 988 samples. Results: There was a strong correlation between fetal fractions determined using the polymorphic assays and using Y‐chromosome sequence quantitation (r = 0.97). Fetal‐fraction measurement between the first and second tubes was highly reproducible (r = 0.98). The fraction of informative loci observed in a clinical series was consistent with predictions based on assay design. Conclusions: The method based on relative quantitation at polymorphic loci on a microarray is accurate and reproducible for fetal‐fraction estimation and is equally informative across global populations. This study provides a useful benchmark for ensuring the reliability and accuracy of fetal‐fraction measurement. © 2018 Roche Sequencing Solutions. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

Recent experimental evidence suggests that changes in the partial pressure of CO2 ( pCO2), in concert with nutrient fertilisation, may result in increased primary production and shifted phytoplankton community composition that favours species lacking adaptations to low CO2 environments. It is not clear whether these results apply in ambient freshwaters, which are already often supersaturated in CO2, and where phytoplankton structure and activity are under complex control of diverse local and regional factors. Here, we use a large-scale comparative study of 69 boreal lakes to explore the influence of existing CO2 gradients ( c. 50-2300 μatm) on phytoplankton community composition and biomass production. While community composition did not respond to pCO2 gradients, gross primary production was enhanced, but only in lakes already supersaturated in CO2, demonstrating that environmental context is key in determining pCO2-phytoplankton interactions. We further argue that increased atmospheric CO2 is unlikely to influence phytoplanktonic composition and production in northern lakes. [ABSTRACT FROM AUTHOR]

Hyperspectral cameras can provide reflectance data at hundreds of wavelengths. This information can be used to derive vegetation indices (VIs) that are correlated with agronomic and physiological traits. However, the data generated by hyperspectral cameras are richer than what can be summarized in a VI. Therefore, in this study, we examined whether prediction equations using hyperspectral image data can lead to better predictive performance for grain yield than what can be achieved using VIs. For hyperspectral prediction equations, we considered three estimation methods: ordinary least squares, partial least squares (a dimension reduction method), and a Bayesian shrinkage and variable selection procedure. We also examined the benefits of combining reflectance data collected at different time points. Data were generated by CIMMYT in 11 maize (Zea mays L.) yield trials conducted in 2014 under heat and drought stress. Our results indicate that using data from 62 bands leads to higher prediction accuracy than what can be achieved using individual VIs. Overall, the shrinkage and variable selection method was the best-performing one. Among the models using data from a single time point, the one using reflectance collected at 28 d after flowering gave the highest prediction accuracy. Combining image data collected at multiple time points led to an increase in prediction accuracy compared with using single-time-point data. [ABSTRACT FROM AUTHOR]

Given the variety of stakeholders involved in cases within family drug courts, efficient communication and information sharing, which are needed to support decision-making, can be quite challenging. Through a case study in one family drug court system, this research employed an action research approach to improve the information sharing process following the Lean Six Sigma methodology. The solutions implemented through this study contributed to improving the quality of the services provided by this court system and its overall productivity. In addition, this research extends our knowledge about methods for improving court systems from which others can learn to guide future improvement efforts. [ABSTRACT FROM AUTHOR]

Political campaigns require constant performance from politicians. This presents ample opportunity for the occurrence of political gaffes. While it is not surprising that political gaffes can have a major impact on political campaigns, the process by which a gaffe is transformed into a meaning-laden defining campaign event is underanalyzed. To address this, we analyze and reconstruct the media trajectory of three instances, two involving Senate candidates (George Allen and Todd Akin) and one a presidential candidate (Mitt Romney), in which gaffes were constructed into meaning-laden events. We find that constructing a political gaffe as a meaning-laden event is a deeply social process. Our research highlights the impact of sousveillance (surveillance from below) and the difficulty that political performers have maintaining consistent 'authentic' performances. Recounting the trajectories of these three gaffes allows for a detailing of the diverse methods by which the hybrid media system was effectively mobilized by 'carrier agents' (actors with narrative capacity and media know-how). Further, we find that these gaffes proved particularly salient because they were interpreted as embodying an authentic representation of the candidate while simultaneously violating emergent norms of inclusive democratic public discourse. [ABSTRACT FROM AUTHOR]

Lake CO2 emissions are increasingly recognized as an important component of the global CO2 cycle, yet the origin of these emissions is not clear, as specific contributions from metabolism and in-lake cycling, versus external inputs, are not well defined. To assess the coupling of lake metabolism with CO2 concentrations and fluxes, we estimated steady state ratios of gross primary production to respiration (GPP:R) and rates of net ecosystem production (NEP = GPP-R) from surface water O2 dynamics (concentration and stable isotopes) in 187 boreal lakes spanning long environmental gradients. Our findings suggest that internal metabolism plays a dominant role in regulating CO2 fluxes in most lakes, but this pattern only emerges when examined at a resolution that accounts for the vastly differing relationships between lake metabolism and CO2 fluxes. Fluxes of CO2 exceeded those from NEP in over half the lakes, but unexpectedly, these effects were most common and typically largest in a subset (~30% of total) of net autotrophic lakes that nevertheless emitted CO2. Equally surprising, we found no environmental characteristics that distinguished this category from the more common net heterotrophic, CO2 outgassing lakes. Excess CO2 fluxes relative to NEP were best predicted by catchment structure and hydrologic properties, and we infer from a combination of methods that both catchment inputs and internal anaerobic processes may have contributed this excess CO2. Together, our findings show that the link between lake metabolism and CO2 fluxes is often strong but can vary widely across the boreal biome, having important implications for catchment-wide C budgets. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective To assess the performance of a directed chromosomal analysis approach in the prenatal evaluation of fetal sex chromosome aneuploidy. Methods We analyzed 432 frozen maternal plasma samples obtained from patients prior to undergoing fetal diagnostic testing. The cohort included women greater than 18 years of age with a singleton pregnancy of greater than 10 weeks gestation. Samples were analyzed using a chromosome-selective approach (DANSRTM) and a risk algorithm that incorporates fetal fraction (FORTETM). Results The cohort included 34 cases of sex chromosome aneuploidy. The assay correctly identified 26 of 27 (92.6%) cases of Monosomy X, one case of XXX, and all six cases of XXY. There were four false positive cases of sex chromosome aneuploidy among 380 euploid cases for an overall false positive rate of less than 1%. Discussion Analysis of the risk for sex chromosome aneuploidies can be accomplished with a targeted assay with high sensitivity. © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]