Hyper-accumulation of legacy fallout radionuclides in cryoconite on Isfallsglaciären (Arctic Sweden) and their downstream distribution

Abstract. The release of legacy contaminants such as fallout radionuclides (FRNs) in response to glacier retreat is a process that has received relatively little attention to date, yet may have consequences as a source of secondary contamination as glaciers melt and down-waste in response to a warming climate. The presence of FRNs in glacier-fed catchments is poorly understood in comparison to other contaminants, yet there is now emerging evidence from multiple regions of the global cryosphere for substantially augmented FRN activities in cryoconite. Here we report concentrated FRNs in both cryoconite and proglacial sediments from the Isfallsglaciären catchment in Arctic Sweden. Activities of some FRNs in cryoconite are 2 orders of magnitude above those found elsewhere in the catchment, and above the activities found in other environmental matrices outside of nuclear exclusion zones. We also describe the presence of the short-lived cosmogenic radionuclide 7Be in cryoconite samples, highlighting the importance of meltwater–sediment interactions in radionuclide accumulation in the ice surface environment. It is currently unknown whether high accumulations of fallout radionuclides in glaciers have the potential to impact local environmental quality through down-wasting and downstream transport of contaminants to the proglacial environment through interaction with sediments and meltwater. We thus recommend that future research in this field focusses on processes of accumulation of FRNs and other environmental contaminants in cryoconite and whether these contaminants are present in quantities harmful for downstream ecosystems.

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Supraglacial Streams and Rivers

Annual Review of Earth and Planetary Sciences ◽

10.1146/annurev-earth-053018-060212 ◽

2019 ◽

Vol 47 (1) ◽

pp. 421-452 ◽

Cited By ~ 6

Author(s):

Lincoln H Pitcher ◽

Laurence C. Smith

Keyword(s):

Sea Level ◽

Transport Processes ◽

Future Research ◽

Sea Level Changes ◽

Ice Dynamics ◽

Surface Mass ◽

Ice Shelves ◽

Streams And Rivers ◽

Ice Surface ◽

Global Sea Level

Supraglacial meltwater channels that flow on the surfaces of glaciers, ice sheets, and ice shelves connect ice surface climatology with subglacial processes, ice dynamics, and eustatic sea level changes. Their important role in transferring water and heat across and into ice is currently absent from models of surface mass balance and runoff contributions to global sea level rise. Furthermore, relatively little is known about the genesis, evolution, hydrology, hydraulics, and morphology of supraglacial rivers, and a first synthesis and review of published research on these unusual features is lacking. To that end, we review their ( a) known geographical distribution; ( b) formation, morphology, and sediment transport processes; ( c) hydrology and hydraulics; and ( d) impact on ice sheet surface energy balance, heat exchange, basal conditions, and ice shelf stability. We conclude with a synthesis of key knowledge gaps and provide recommendations for future research. ▪ Supraglacial streams and rivers transfer water and heat on glaciers, connecting climate with subglacial hydrology, ice sliding, and global sea level. ▪ Ice surface melting may expand under a warming climate, darkening the ice surface and further increasing melt.

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Recent Trends in Pharmaceuticals Removal from Water Using Electrochemical Oxidation Processes

Environments ◽

10.3390/environments8080085 ◽

2021 ◽

Vol 8 (8) ◽

pp. 85

Author(s):

Georgios Bampos ◽

Athanasia Petala ◽

Zacharias Frontistis

Keyword(s):

Electrochemical Oxidation ◽

Emerging Contaminants ◽

Three Dimensional ◽

Future Research ◽

Environmental Matrices ◽

Oxidation Processes ◽

Electrosynthesis Of Hydrogen Peroxide ◽

Physicochemical Methods ◽

Recent Trends ◽

Environmental Electrochemistry

Nowadays, the research on the environmental applications of electrochemistry to remove recalcitrant and priority pollutants and, in particular, drugs from the aqueous phase has increased dramatically. This literature review summarizes the applications of electrochemical oxidation in recent years to decompose pharmaceuticals that are often detected in environmental samples such as carbamazapine, sulfamethoxazole, tetracycline, diclofenac, ibuprofen, ceftazidime, ciprofloxacin, etc. Similar to most physicochemical processes, efficiency depends on many operating parameters, while the combination with either biological or other physicochemical methods seems particularly attractive. In addition, various strategies such as using three-dimensional electrodes or the electrosynthesis of hydrogen peroxide have been proposed to overcome the disadvantages of electrochemical oxidation. Finally, some guidelines are proposed for future research into the applications of environmental electrochemistry for the degradation of xenobiotic compounds and micropollutants from environmental matrices. The main goal of the present review paper is to facilitate future researchers to design their experiments concerning the electrochemical oxidation processes for the degradation of micropollutants/emerging contaminants, especially, some specific drugs considering, also, the existing limitations of each process.

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Methodological considerations in assessment of language lateralisation with fMRI: a systematic review

PeerJ ◽

10.7717/peerj.3557 ◽

2017 ◽

Vol 5 ◽

pp. e3557 ◽

Cited By ~ 22

Author(s):

Abigail R. Bradshaw ◽

Dorothy V.M. Bishop ◽

Zoe V.J. Woodhead

Keyword(s):

Systematic Review ◽

Open Science ◽

Future Research ◽

Language Functions ◽

Multiple Regions ◽

Invasive Method ◽

Science Framework ◽

Methodological Considerations ◽

The Right ◽

Language Laterality

The involvement of the right and left hemispheres in mediating language functions has been measured in a variety of ways over the centuries since the relative dominance of the left hemisphere was first known. Functional magnetic resonance imaging (fMRI) presents a useful non-invasive method of assessing lateralisation that is being increasingly used in clinical practice and research. However, the methods used in the fMRI laterality literature currently are highly variable, making systematic comparisons across studies difficult. Here we consider the different methods of quantifying and classifying laterality that have been used in fMRI studies since 2000, with the aim of determining which give the most robust and reliable measurement. Recommendations are made with a view to informing future research to increase standardisation in fMRI laterality protocols. In particular, the findings reinforce the importance of threshold-independent methods for calculating laterality indices, and the benefits of assessing heterogeneity of language laterality across multiple regions of interest and tasks. This systematic review was registered as a protocol on Open Science Framework: https://osf.io/hyvc4/.

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Abstract WP336: Global Variation in the Representation of Women in Contemporary Acute Stroke Trials

Stroke ◽

10.1161/str.51.suppl_1.wp336 ◽

2020 ◽

Vol 51 (Suppl_1) ◽

Author(s):

Brent Strong ◽

Virginia Howard ◽

Mathew J Reeves

Keyword(s):

Acute Stroke ◽

Meta Analysis ◽

Geographic Region ◽

Asia Pacific ◽

Absolute Difference ◽

Future Research ◽

Eligibility Criteria ◽

Representation Of Women ◽

Incidence Studies ◽

Multiple Regions

Introduction: Women have historically been underrepresented in RCTs of cardiovascular disease. We undertook a review of acute stroke RCTs to determine whether women were equitably represented and whether any sex disparity varied across geographic region. Methods: We searched for papers describing primary results of acute stroke RCTs published 2013-2018 in 9 major journals and abstracted the proportion of trial participants that were women (PPW). We then searched for incidence studies from the geographic regions in which trial enrollment took place and estimated the proportion of incident strokes occurring in women (PSW) in each region (i.e., North America, Europe, Asia Pacific, Multiple Regions). We quantified the representation of women using the enrollment disparity difference (EDD) calculated as the absolute difference between the two proportions (i.e., PSW - PPW). An EDD greater than 0 indicated a disparity in favor of men. We pooled EDDs from individual RCTs using random effects meta-analysis to estimate overall and region-specific disparities. Results: Among 60 trials the PPW ranged from 33.8% to 56.9% (median 44.7%). The overall pooled EDD was 0.07 (95% CI=0.06-0.08, Q p<0.001, I 2 =85.8%) (Figure), indicating that 7% more men were included in the trials, relative to the underlying incidence. A statistically significant EDD existed in all regions; the magnitude was largest for RCTs with enrollment from Asia Pacific (EDD=0.11, 95% CI=0.10-0.13) and Multiple Regions (EDD=0.10, 95% CI=0.08-0.12) and smallest among North American and European trials (EDD 0.04 and 0.06, respectively). All region-specific summary estimates showed significant between study heterogeneity apart from Asia (Q p=0.102, I 2 =38.4%). Conclusions: Women were underrepresented globally in contemporary acute stroke RCTs; the magnitude of the disparity differed between regions. Future research should focus on trial eligibility criteria that may contribute to this disparity.

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Changing wildfire, changing forests: the effects of climate change on fire regimes and vegetation in the Pacific Northwest, USA

Fire Ecology ◽

10.1186/s42408-019-0062-8 ◽

2020 ◽

Vol 16 (1) ◽

Cited By ~ 8

Author(s):

Jessica E. Halofsky ◽

David L. Peterson ◽

Brian J. Harvey

Keyword(s):

Pacific Northwest ◽

Fire Regimes ◽

Tree Regeneration ◽

Ecosystem Change ◽

Fire Intensity ◽

Future Research ◽

Fuel Treatments ◽

Warming Climate ◽

Resource Managers ◽

The Pacific

Abstract Background Wildfires in the Pacific Northwest (Washington, Oregon, Idaho, and western Montana, USA) have been immense in recent years, capturing the attention of resource managers, fire scientists, and the general public. This paper synthesizes understanding of the potential effects of changing climate and fire regimes on Pacific Northwest forests, including effects on disturbance and stress interactions, forest structure and composition, and post-fire ecological processes. We frame this information in a risk assessment context, and conclude with management implications and future research needs. Results Large and severe fires in the Pacific Northwest are associated with warm and dry conditions, and such conditions will likely occur with increasing frequency in a warming climate. According to projections based on historical records, current trends, and simulation modeling, protracted warmer and drier conditions will drive lower fuel moisture and longer fire seasons in the future, likely increasing the frequency and extent of fires compared to the twentieth century. Interactions between fire and other disturbances, such as drought and insect outbreaks, are likely to be the primary drivers of ecosystem change in a warming climate. Reburns are also likely to occur more frequently with warming and drought, with potential effects on tree regeneration and species composition. Hotter, drier sites may be particularly at risk for regeneration failures. Conclusion Resource managers will likely be unable to affect the total area burned by fire, as this trend is driven strongly by climate. However, fuel treatments, when implemented in a spatially strategic manner, can help to decrease fire intensity and severity and improve forest resilience to fire, insects, and drought. Where fuel treatments are less effective (wetter, high-elevation, and coastal forests), managers may consider implementing fuel breaks around high-value resources. When and where post-fire planting is an option, planting different genetic stock than has been used in the past may increase seedling survival. Planting seedlings on cooler, wetter microsites may also help to increase survival. In the driest topographic locations, managers may need to consider where they will try to forestall change and where they will allow conversions to vegetation other than what is currently dominant.

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Methodological considerations in assessment of language lateralisation with fMRI: a systematic review

10.7287/peerj.preprints.2962v2 ◽

2017 ◽

Author(s):

Abigail R. Bradshaw ◽

Dorothy V. M. Bishop ◽

Zoe V. J. Woodhead

Keyword(s):

Future Research ◽

Functional Magnetic Resonance ◽

Reliable Measurement ◽

Language Functions ◽

Non Invasive ◽

Multiple Regions ◽

Invasive Method ◽

Methodological Considerations ◽

The Right ◽

Language Laterality

The involvement of the right and left hemispheres in mediating language functions has been measured in a variety of ways over the centuries since the relative dominance of the left hemisphere was first known. Functional magnetic resonance imaging (fMRI) presents a useful non-invasive method of assessing lateralisation that is being increasingly used in clinical practice and research. However, the methods used in the fMRI laterality literature currently are highly variable, making systematic comparisons across studies difficult. Here we consider the different methods of quantifying and classifying laterality that have been used in fMRI studies since 2000, with the aim of determining which give the most robust and reliable measurement. Recommendations are made with a view to informing future research to increase standardisation in fMRI laterality protocols. In particular, the findings reinforce the importance of threshold-independent methods for calculating laterality indices, and the benefits of assessing heterogeneity of language laterality across multiple regions of interest and tasks.

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Methodological considerations in assessment of language lateralisation with fMRI: a systematic review

10.7287/peerj.preprints.2962 ◽

2017 ◽

Author(s):

Abigail R. Bradshaw ◽

Dorothy V. M. Bishop ◽

Zoe V. J. Woodhead

Keyword(s):

Future Research ◽

Functional Magnetic Resonance ◽

Reliable Measurement ◽

Language Functions ◽

Non Invasive ◽

Multiple Regions ◽

Invasive Method ◽

Methodological Considerations ◽

The Right ◽

Language Laterality

The involvement of the right and left hemispheres in mediating language functions has been measured in a variety of ways over the centuries since the relative dominance of the left hemisphere was first known. Functional magnetic resonance imaging (fMRI) presents a useful non-invasive method of assessing lateralisation that is being increasingly used in clinical practice and research. However, the methods used in the fMRI laterality literature currently are highly variable, making systematic comparisons across studies difficult. Here we consider the different methods of quantifying and classifying laterality that have been used in fMRI studies since 2000, with the aim of determining which give the most robust and reliable measurement. Recommendations are made with a view to informing future research to increase standardisation in fMRI laterality protocols. In particular, the findings reinforce the importance of threshold-independent methods for calculating laterality indices, and the benefits of assessing heterogeneity of language laterality across multiple regions of interest and tasks.

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Advances in Instrumental Analysis of Brominated Flame Retardants: Current Status and Future Perspectives

International Scholarly Research Notices ◽

10.1155/2014/651834 ◽

2014 ◽

Vol 2014 ◽

pp. 1-21 ◽

Cited By ~ 1

Author(s):

Mohamed Abou-Elwafa Abdallah

Keyword(s):

Flame Retardants ◽

Search Strategy ◽

Degradation Products ◽

Brominated Flame Retardants ◽

Current Status ◽

Future Research ◽

Environmental Matrices ◽

Factors Affecting ◽

Literature Search Strategy

This review aims to highlight the recent advances and methodological improvements in instrumental techniques applied for the analysis of different brominated flame retardants (BFRs). The literature search strategy was based on the recent analytical reviews published on BFRs. The main selection criteria involved the successful development and application of analytical methods for determination of the target compounds in various environmental matrices. Different factors affecting chromatographic separation and mass spectrometric detection of brominated analytes were evaluated and discussed. Techniques using advanced instrumentation to achieve outstanding results in quantification of different BFRs and their metabolites/degradation products were highlighted. Finally, research gaps in the field of BFR analysis were identified and recommendations for future research were proposed.

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The potential for gamma-emitting radionuclides to contribute to an understanding of erosion processes in South Africa

Proceedings of the International Association of Hydrological Sciences ◽

10.5194/piahs-375-29-2017 ◽

2017 ◽

Vol 375 ◽

pp. 29-34 ◽

Cited By ~ 1

Author(s):

Ian D. L. Foster ◽

John Boardman ◽

Adrian L. Collins ◽

Ruth Copeland-Phillips ◽

Nikolaus J. Kuhn ◽

...

Keyword(s):

South Africa ◽

Sediment Yield ◽

210Pb Dating ◽

Future Research ◽

Alluvial Fans ◽

210Pb And 137Cs ◽

Sedimentary Environments ◽

Erosion Processes ◽

Fallout Radionuclides ◽

Sand And Gravel

Abstract. Several research projects undertaken by the authors and others over the last 14 years have used fallout and geogenic radionuclides for understanding erosion processes and sediment yield dynamics in South Africa over the last 100–200 years as European settlers colonised the interior plains and plateaux of the country and imported new livestock and farming techniques to the region. These projects have used two fallout radionuclides (210Pb and 137Cs) to date sediments accumulating in reservoirs, farm dams, wetlands, alluvial fans and floodouts and have used other fallout nuclides (7Be) and long-lived geogenic radionuclides (e.g. 40K, 235U) as part of a composite fingerprint exploring contemporary sediment sources and changes to sources through time. While successful in many parts of the world, applying these techniques in Southern Africa has posed a number of challenges often not encountered elsewhere. Here we explore some of the benefits and challenges in using gamma-emitting radionuclides, especially 137Cs, in these landscapes. Benefits include the potential for discriminating gully sidewall from topsoil sources, which has helped to identify contemporary gully systems as sediment conduits, rather than sources, and for providing a time-synchronous marker horizon in a range of sedimentary environments that has helped to develop robust chronologies. Challenges include the spatial variability in soil cover on steep rocky hillslopes, which is likely to challenge assumptions about the uniformity of initial fallout nuclide distribution, the paucity of stable (non-eroding) sites in order to estimate atmospheric fallout inventories, and the limited success of 210Pb dating in some rapidly accumulating high altitude catchments where sediments often comprise significant amounts of sand and gravel. Despite these challenges we present evidence suggesting that the use of gamma-emitting radionuclides can make a significant contribution to our understanding of erosion processes and sediment yield dynamics. Future research highlighted in the conclusion will try to address current challenges and outline new projects established to address them more fully.

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