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Item Trophic magnification rates of eighteen trace elements in freshwater food webs(Science of The Total Environment, 2024-12) Pelletier, Alexander R.; Villamarin, Francisco; Campos-Silva, João V.; Scabin, Andressa B.; Doig, Lorne E.; Jardine, Timothy D.Trace elements play diverse roles in animal physiology ranging from essential micronutrients to potent toxicants. Despite animals accumulating many trace elements through their diets, relationships between trophic positions and biological concentrations of most trace elements remain poorly described. We report trophic transfer rates of Al, As, Ba, Cd, Co, Cu, Fe, Hg, Mn, Ni, Pb, Se, Sr, Ti, Tl, U, V, and Zn from 31 freshwaters located in distinct biogeographic regions. Elemental concentrations and stable nitrogen isotope ratios (proxies for trophic position) were determined in zooplankton, molluscs, insects, and fishes from all sites. Trophic magnification factors (TMFs) were calculated as the mean fraction of each element that transferred from prey to predators at each site. TMFs >1 indicate biomagnification and TMFs <1 indicate biodilution. Mercury was the only biomagnifying element (median TMF = 3.77), and selenium neither biomagnified nor biodiluted (median TMF = 1.01). All 16 remaining elements biodiluted, with median TMFs ranging from 0.07 (uranium) to 0.60 (thallium). We used a model selection procedure to determine whether intrinsic physical and chemical elemental properties explained differences in TMFs among elements. Elements with high covalent bonding indices (Q) had marginally greater TMFs than elements with low Q values. Based on their high Q values, we recommend investigation into the trophic transfer rates of ten additional trace elements, some of which may biomagnify through some aquatic food webs. The high variability in TMFs within elements suggests that ecological factors are likely more important than intrinsic elemental properties at determining elemental TMFs.Item Assessing the Readiness and Capacity of Biosphere Regions to Implement Equity, Diversity, and Inclusion - A Desktop Review(2024-09) Boakye-Danquah, John; Marfo, Crenda OThis report present the findings of a desktop review sponsored by the TRANSECTS to examine the readiness and capacity of Biosphere Regions (BR) in Canada and other conservation organizations to implement Equity, Diversity and Inclusion (EDI). The search was limited to broad EDI considerations focusing on terms such as “equity”, “diversity”, “equality”, “inclusion”, “accessibility”, “justice”, “minority”, “reconciliation”, “SDG 5” and “SDG 10”. The findings revealed that majority of BRs and similar conservation organizations are actively engaging in reconciliation efforts. These efforts include collaborative planning with Indigenous communities, acknowledging traditional territories, providing services for Indigenous youth, and incorporating Indigenous knowledge into conservation and sustainability initiatives. The integration of EDI varies across BRs. Twelve BR websites included at least one reference to an EDI term, while five did not mention EDI terms. Key findings include: 66% of BRs referenced "diversity," primarily highlighting the inclusion of cultural knowledge in work practices and ensuring diverse representation among staff, board members, and volunteers. 28% of BRs mentioned "inclusion" as a core value, particularly in hiring practices, community engagement, and knowledge creation. 22% of BRs integrated "equity" into mission and vision statements, focusing on improving recruitment, promoting economic fairness, and ensuring justice for diverse community needs. Some also emphasized internal equity initiatives for staff. Only 6% of BRs referenced "accessibility," acknowledging the need for accommodations for people with disabilities in hiring practices. 22% of BRs referenced SDG 5 (gender equality) and SDG 10 (reduced inequalities). BRs primarily emphasized Indigenous Peoples and Youth in their equity efforts. Other equity groups, including women, people with disabilities, racialized/visible minorities, older adults, and 2SLGBTQ+ individuals, received comparatively less focus from BRs.Item Behind the scenes with genomics researchers(Frontiers in Genetics, 2024-12) Mont'Alverne, Renata; Bradford, Lori; Buckmaster, Cheryl; Strickert, Graham; MacLean, Jason; Dupont, DianeAlthough lab-coat genomics scientists are highly skilled and involved in pioneering work, few studies have examined their perceptions on what they do, and how they relate with others in interdisciplinary work. Recognizing that gap, we were curious to talk with scientists about their current work and positionalities related to the use of genomics for bioremediation. Using unstructured open-ended interviews and thematic analysis, we interviewed researchers with diverse genomics-related expertise. Emerging topics were grouped into two broad categories akin to Bronfenbrenner’s nested developmental model: microsystem matters, comprising technical advances, barriers, and localized concerns; and macrosystem matters, exploring wider reflections and the philosophies of genomics and society. At the microsystem level, findings revealed differences of opinion about methodological steps, but there was agreement about the incompleteness of databases and the absence of established reference values. These two problems may not only impact a project’s progress but also the ability to gauge success, affecting budgeting, human resource needs, and overall stress. At the macrosystem level, scientists voiced concerns about how different social groups perceive and accept genomics applications, as those tend to be viewed by lay persons as genetic interventions. Another focus was on how academic publication slows progress because it is orientated toward positive results while gaps in knowledge could be filled by publishing negative results or methodological barriers. This study underscores scientists’ self-awareness within the genomics discipline, acknowledging how their beliefs and biases shape research outcomes. It illuminates critical reflections essential for navigating societal and scientific landscapes in genomics research.Item Exploring energy transition narratives through mayoral insights using artificial intelligence(Elsevier, 2024-12-21) Ahmed, Fatma; Ahmed, Rwan; Poelzer, Greg; Poelzer, Gregory; Söderberg, Charlotta; Zapata, Oscar; Guilmette, ElainaThis paper explores energy transition dynamics in three Arctic cities: Luleå (Sweden), Fairbanks (Alaska), and Yellowknife (Canada), with a focus on sustainable urban development. Semi-structured interviews with the mayors of these cities provide insights into their decision-making processes and strategies regarding energy transitions. Using Natural Language Processing (NLP) for semantic analysis, the study uncovers implicit priorities, challenges, and aspirations from the qualitative data. The analysis is guided by the theory of planned behavior, which helps to explain the underlying motivations, attitudes, and perceived behavioral control that influence policy decisions. Results reveal common themes such as balancing environmental goals with economic and social concerns, while also highlighting context-specific challenges in each city. This research contributes to the understanding the role of municipal leadership in energy transitions and demonstrates the effectiveness of NLP techniques in extracting meaningful insights from interviews. The findings aim to inform policymakers and urban planners on fostering sustainable energy transitions in Arctic regions.Item “Are you prepared or not?”: An intersectional analysis of a community-engaged climate change vulnerability assessment and adaptation planning process with Tsáá? Ché Ne Dane(Environmental Science and Policy, 2024-12-30) Sidloski, Michaela; Reed, Maureen; Andrews-Key, SheriIntersectional analyses of climate hazards have demonstrated that social dimensions play important roles in how people experience and respond to climate change and extreme weather events. Despite these insights, inter- sectional scholarship has faced criticism around its theoretical orientation and the resulting challenges of doing applied intersectional research to understand social dimensions of climate change. This article demonstrates the value of an intersectional feminist lens to community-level planning for climate change. Working with an Indigenous community in northern British Columbia, Canada, the research revealed that social dimensions including culture, age, gender, and spirituality combined in distinct and various ways to influence how the community framed the problem of climate change, expressed agency, understood impacts and vulnerability, and proposed responses. Attending to these dimensions throughout a community-engaged climate change vulnera- bility assessment and adaptation planning process illuminated differences among groups, while also exposing shared goals and areas of overlap among diverse perspectives and worldviews. Beyond exposing commonalities, consistent consideration of social dimensions also enhanced local adaptive capacity and shaped the planning and decision-making process by informing project framing and design, methods selection and participant recruit- ment, and developing meaningful outputs. We use this evidence to demonstrate the practical application of an intersectional lens and to explain how embedding consideration of social dimensions within climate change vulnerability assessment and adaptation planning processes can produce better contextualization, greater buy-in, and more meaningful outcomes for communities across Canada and beyond.Item Connecting hydrological modelling and forecasting from global to local scales: Perspectives from an international joint virtual workshop(Journal of Flood Risk Management, 2023) Dasgupta, Antara; Arnal, Louise; Emerton, Rebecca; Harrigan, Shaun; Matthews, Gwyneth; Muhammad, Ameer; O'Regan, Karen; Pérez-Ciria, Teresa; Valdez, Emixi; van Osnabrugge, Bart; Werner, Micha; Buontempo, Carlo; Cloke, Hannah; Pappenberger, Florian; Pechlivanidis, Ilias G; Prudhomme, Christel; Maria-Helena, Ramos; Salamon, PeterThe unprecedented progress in ensemble hydro-meteorological modelling and forecasting on a range of temporal and spatial scales, raises a variety of new challenges which formed the theme of the Joint Virtual Workshop, ‘Connecting global to local hydrological modelling and forecasting: challenges and scientific advances’. Held from 29 June to 1 July 2021, this workshop was co-organised by the European Centre for Medium-Range Weather Forecasts (ECMWF), the Copernicus Emergency Management (CEMS) and Climate Change (C3S) Services, the Hydrological Ensemble Prediction EXperiment (HEPEX), and the Global Flood Partnership (GFP). This article aims to summarise the state-of-the-art presented at the workshop and provide an early career perspective. Recent advances in hydrological modelling and forecasting, reflections on the use of forecasts for decision-making across scales, and means to minimise new barriers to communication in the virtual format are also discussed. Thematic foci of the workshop included hydrological model development and skill assessment, uncertainty communication, forecasts for early action, co-production of services and incorporation of local knowledge, Earth observation, and data assimilation. Connecting hydrological services to societal needs and local decision-making through effective communication, capacity-building and co-production was identified as critical. Multidisciplinary collaborations emerged as crucial to effectively bring newly developed tools to practice.Item FROSTBYTE: a reproducible data-driven workflow for probabilistic seasonal streamflow forecasting in snow-fed river basins across North America(Hydrology and Earth System Sciences, 2024-09) Arnal, Louise; Clark, Martyn P.; Pietroniro, Alain; Vionnet, Vincent; Casson, David R; Whitfield, Paul; Fortin, Vincent; Wood, Andrew; Knoben, Wouter; Newton, Brandi W; Walford, ColleenSeasonal streamflow forecasts provide key information for decision-making in fields such as water supply management, hydropower generation, and irrigation scheduling. The predictability of streamflow on seasonal timescales relies heavily on initial hydrological conditions, such as the presence of snow and the availability of soil moisture. In high-latitude and high-altitude headwater basins in North America, snowmelt serves as the primary source of runoff generation. This study presents and evaluates a data-driven workflow for probabilistic seasonal streamflow forecasting in snow-fed river basins across North America (Canada and the USA). The workflow employs snow water equivalent (SWE) measurements as predictors and streamflow observations as predictands. Gap-filling of SWE datasets is accomplished using quantile mapping from neighboring SWE and precipitation stations, and principal component analysis is used to identify independent predictor components. These components are then utilized in a regression model to generate ensemble hindcasts of streamflow volumes for 75 nival basins with limited regulation from 1979 to 2021, encompassing diverse geographies and climates. Using a hindcast evaluation approach that is user-oriented provides key insights for snow-monitoring experts, forecasters, decision-makers, and workflow developers. The analysis presented here unveils a wide spectrum of predictability and offers a glimpse into potential future changes in predictability. Late-season snowpack emerges as a key factor in predicting spring and summer volumes, while high precipitation during the target period presents challenges to forecast skill and streamflow predictability. Notably, we can predict lower-than-normal and higher-than-normal streamflows during spring to early summer with lead times of up to 5 months in some basins. Our workflow is available on GitHub as a collection of Jupyter Notebooks, facilitating broader applications in cold regions and contributing to the ongoing advancement of methodologies.Item Community Governance for Small Modular Reactor (SMR) Development: Lessons from Northern and Indigenous Energy Projects(The Northern Review, 2024) Iakovleva, MariiaRemote Indigenous communities in northern Canada often suffer from energy insecurity and energy poverty. In developing local clean energy production, there is an obvious benefit for government and industry partnering with these communities. However, the record of these partnerships is poor, with some failing to produce the expected benefits and others failing to get off the ground at all. This article is based on a study of four case studies of renewable energy projects in Indigenous communities in northern Saskatchewan and Alberta, in which I interviewed community project leaders to understand why these communities were interested in energy projects, what they hoped to achieve, and their experience with their partners. I also interviewed government and industry partners. While the results underline the importance of Indigenous intermediaries who can move easily between the communities and the larger energy production context, they also reveal a fundamental misalignment of expectations between Indigenous communities and their partners. Recent discussions about the potential for small modular nuclear reactors (SMRs) in remote communities have generally focused on features of the technology rather than on aspects of the social context of Indigenous communities. I argue that, for communities to fully understand the advantages and drawbacks of this technology, much more attention needs to be paid to the construction of a safe space where communities can frame the discussion within Indigenous world views and lived experience. I offer some policy suggestions for how this space can be constructed and protected.Item Remote Sensing of Chlorophyll-a in Clear vs. Turbid Waters in Lakes(Remote Sensing, 2024-09) Fendereski, Forough; Creed, Irena; Trick, Charles GChlorophyll-a (Chl-a), a proxy for phytoplankton biomass, is one of the few biological water quality indices detectable using satellite observations. However, models for estimating Chl-a from satellite signals are currently unavailable for many lakes. The application of Chl-a prediction algorithms may be affected by the variance in optical complexity within lakes. Using Lake Winnipeg in Canada as a case study, we demonstrated that separating models by the lake’s basins [north basin (NB) and south basin (SB)] can improve Chl-a predictions. By calibrating more than 40 commonly used Chl-a estimation models using Landsat data for Lake Winnipeg, we achieved higher correlations between in situ and predicted Chl-a when building models with separate Landsat-to-in situ matchups from NB and SB (R2 = 0.85 and 0.76, respectively; p < 0.05), compared to using matchups from the entire lake (R2 = 0.38, p < 0.05). In the deeper, more transparent waters of the NB, a green-to-blue band ratio provided better Chl-a predictions, while in the shallower, highly turbid SB, a red-to-green band ratio was more effective. Our approach can be used for rapid Chl-a modeling in large lakes using cloud-based platforms like Google Earth Engine with any available satellite or time series length.Item Continental-scale nutrient and contaminant delivery by Pacific salmon(Nature, 2024-10-09) Brandt, Jessica E.; Wesner, Jeff F.; Ruggerone, Gregory; Jardine, Timothy D; Eagles-Smith, Collin A.; Ruso, Gabrielle E.; Stricker, Craig A.; Voss, Kristofor A.; Walters, David M.The movement of large amounts of nutrients by migrating animals has ecological benefits for recipient food webs that may be offset by co-transported contaminants. Salmon spawning migrations are archetypal of this process, carrying marine-derived materials to inland ecosystems where they stimulate local productivity but also enhance contaminant exposure. Pacific salmon abundance and biomass are higher now than in the last century, reflecting substantial shifts in community structure8 that probably altered nutrient versus contaminant delivery. Here we combined nutrient and contaminant concentrations with 40 years of annual Pacific salmon returns to quantify how changes in community structure influenced marine to freshwater inputs to western North America. Salmon transported tonnes of nutrients and kilograms of contaminants to freshwaters annually. Higher salmon returns (1976–2015) increased salmon-derived nutrient and contaminant inputs by 30% and 20%, respectively. These increases were dominated by pink salmon, which are short-lived, feed lower in marine food webs than other salmon species, and had the highest nutrient-to-contaminant ratios. As a result, the delivery of nutrients increased at a greater rate than the delivery of contaminants, and salmon inputs became more ecologically beneficial over time. Even still, contaminant loadings may represent exposure concerns for some salmon predators. The Pacific salmon example demonstrates how long-term environmental changes interact with nutrient and contaminant movement across large spatial scales and provides a model for exploring similar patterns with other migratory species.Item Evaluating innovation in transdisciplinary sustainability education: TRANSECTS’ international learning labs(MedPharm Publications, 2024-09-26) Rosenberg, Eureta; Cockburn, Jessica; Reed, Maureen; James, Wendy; Gengelbach, Jana; Walk, HeikeEvaluative research can advance sustainability education through the learning it can enable, at micro and systems levels. This proposition is explored by examining evaluation practice in a 6-year international programme entitled Transdisciplinary Education Collaboration for Transformations in Sustainability involving universities and biosphere reserves/regions in Germany, South Africa and Canada. A Transdisciplinary International Learning Lab (TILL) was evaluated using a theory-based evaluation approach and interviews, focus groups and questionnaires that yielded qualitative data. Through meta-reflection, we concluded that our TILL had elements of a Field School, rather than a Learning Lab, and that our curriculum required more explicit deliberation among programme developers and implementers towards a deeper and shared understanding of pedagogical assumptions and more congruent practice of transdisciplinary and transformative sustainability education. The reflective, theory-based approach enabled learning from evaluation and was captured in a shared refinement of the theory of change, which makes it explicit that learning from pedagogical innovations is not only for students but also for academics. The paper is an invitation to other innovators in sustainability science, education and evaluation in higher education, to share related findings.Item Unequally happy: happiness inequality across satisfaction domainsin a developing-country context(Springer, 2024) Zapata, OscarSubjective measures of well-being, such as happiness, occupy a rapidly growing body in the academic literature. However, how happiness levels are distributed across populations and social groups is less well known, especially in the context of developing countries. In this paper, I study happiness inequality at the district level in Ecuador, considering diverse domains of individual satisfaction. Concretely, I calculate Gini coefficients for happiness domains and identify the determinants of happiness inequality levels using a panel dataset for 584 districts over three years. The findings show that happiness inequality is lower regarding overall satisfaction and satisfaction with marital status and social life and higher regarding work and financial conditions, and the government. The results also suggest that average happiness level and income inequality are consistent determinants of happiness inequality. Lastly, I divide the sample by gender, place of residence, ethnicity and education levels to explore the differences across population groups. Policy discussion and implications follow the quantitative analysis.Item Looking back - looking forward: A novel multi-time slice weight-of-evidence approach for defining reference conditions to assess the impact of human activities on lake systems(Elsevier, 2018) Hollert, Henner; Crawford, Sarah E.; Brack, Werner; Brinkmann, Markus; Fischer, Elske; Hartmann, Kai; Keiter, Steffen; Ottermanns, Richard; Ouellet, Jacob; Rinke, Karsten; Roß-Nickoll, Martina; Schäffer, Andreas; Schüth, Christoph; Schulze, Tobias; Schwarz, Anja; Seiler, Thomas-Benjamin; Wessels, Martin; Hinderer, Matthias; Schwalb, AntjeLake ecosystems are sensitive recorders of environmental changes that provide continuous archives at annual to decadal resolution over thousands of years. The systematic investigation of land use changes and emission of pollutants archived in Holocene lake sediments as well as the reconstruction of contamination, background conditions, and sensitivity of lake systems offer an ideal opportunity to study environmental dynamics and consequences of anthropogenic impact that increasingly pose risks to human well-being. This paper discusses the use of sediment and other lines of evidence in providing a record of historical and current contamination in lake ecosystems. We present a novel approach to investigate impacts from human activities using chemical-analytical, bioanalytical, ecological, paleolimnological, paleoecotoxicological, archeological as well as modeling techniques. This multi-time slice weight-of-evidence (WOE) approach will generate knowledge on conditions prior to anthropogenic influence and provide knowledge to (i) create a better understanding of the effects of anthropogenic disturbances on biodiversity, (ii) assess water quality by using quantitative data on historical pollution and persistence of pollutants archived over thousands of years in sediments, and (iii) define environmental threshold values using modeling methods. This technique may be applied in order to gain insights into reference conditions of surface and ground waters in catchments with a long history of land use and human impact, which is still a major need that is currently not yet addressed within the context of the European Water Framework Directive.Item Assessing the fate of brown trout (Salmo trutta) environmental DNA in a natural stream using a sensitive and specific dual-labelled probe(Elsevier, 2019) Deutschmann, Björn; Müller, Anne-Kathrin; Hollert, Henner; Brinkmann, MarkusEnvironmental DNA (eDNA) analysis in the aquatic environment has emerged as a promising tool for diagnosis of the ecological status in comprehensive monitoring strategies and might become useful in context of the European Water Framework Directive (WFD) and other legislations to derive stressor-specific indicators. Despite many studies having made significant progress for the future use of eDNA in terms of ecosystem composition and detection of invasive/rare species in inland waters, much remains unknown about the transport and fate of eDNA under natural environmental conditions. We designed a specific dual-labelled probe to detect brown trout (Salmo trutta, L.) eDNA and used the probe to describe the fate of eDNA released from an aquaculture facility into the low mountain range stream Wehebach, Germany. The probe was shown to be specific to brown trout, as ponds housing rainbow trout (Oncorhynchus mykiss) did not test positive. Even though we observed different strengths of eDNA signals for three ponds containing different brown trout quantities, no significant correlation was found between biomass (kg/L) and eDNA quantity. Our results indicate that the release of DNA from brown trout might be life stage and/or age-dependent. The effluents of the aquaculture facility were a source of high levels of eDNA which resulted in the greatest abundance of brown trout eDNA directly downstream of the facility. Despite the natural occurrence of brown trout in the Wehebach, as shown by ecological investigations conducted by authorities of the federal state of North Rhine-Westphalia (Germany) and personal observations, we observed a significant decrease of relative abundance of eDNA in the Wehebach within the first 1.5 km downstream of the aquaculture. Our results suggest that concentrations of eDNA in running waters rapidly decrease under natural conditions due to dilution and degradation processes, which might have important implications for the utility of eDNA in environmental research.Item Ecotoxicity of NSO-heterocycles (NSO-HET) and short-chained alkyl phenols (SCAP) commonly detected in contaminated groundwater(Society of Environmental Toxicology and Chemistry, 2019) Brinkmann, Markus; Schneider, Anna-Lena; Bluhm, Kerstin; Schiwy, Sabrina; Lehmann, Gunnar; Deutschmann, Björn; Müller, Axel; Tiehm, Andreas; Hollert, HennerNitrogen, sulfur, or oxygen heterocyclic aromatic hydrocarbons (NSO-HETs) and short-chained alkyl phenols (SCAPs) are commonly detected in groundwater at contaminated sites and in the surrounding environment. It is now scientific consensus that these chemicals pose a risk to human and ecosystem health. However, toxicity data are comparably fragmentary, and only few studies have addressed the ecotoxicity of NSO-HETs and SCAPs in a systematic and comparative fashion. To overcome this shortcoming, we tested 18 SCAPs, 16 NSO-HETs, as well as the homocyclic hydrocarbons indane and indene in the Microtox® assay with Aliivibrio fischeri, the growth inhibition test with Desmodesmus subspicatus, the acute immobilization assay with Daphnia magna, as well as the fish embryo toxicity test with embryos of the zebrafish (Danio rerio). Because of the physicochemical properties of the tested chemicals (limited water solubility, volatility, and sorption to test vessels), actual exposure concentrations in test media and their dissipation over time were analytically quantified by means of gas chromatography with mass spectrometry. Analytically corrected effect levels (median effect and lethal concentrations) ranged from 0.017 to 180 mg L–1, underlining the environmental relevance of some NSO-HETs and SCAPs. Para-substituted phenols showed the overall greatest toxicities in all 4 toxicity tests. We provide, for the first time, a complete high-quality data set in support of better environmental risk assessments of these chemicals.Item Bioactivation of Quinolines in a Recombinant Estrogen Receptor Transactivation Assay Is Catalyzed by N-Methyltransferases(ACS Publications, 2019) Brinkmann, Markus; Barz, Bogdan; Carrière, Danielle; Velki, Mirna; Smith, Kilian; Meyer-Alert, Henriette; Müller, Yvonne; Thalmann, Beat; Bluhm, Kersti; Schiwy, Sabrina; Hotz, Simone; Salowsky, Helena; Tiehm, Andreas; Hecker, Markus; Hollert, HennerHydroxylation of polyaromatic compounds through cytochromes P450 (CYPs) is known to result in potentially estrogenic transformation products. Recently, there has been an increasing awareness of the importance of alternative pathways such as aldehyde oxidases (AOX) or N-methyltransferases (NMT) in bioactivation of small molecules, particularly N-heterocycles. Therefore, this study investigated the biotransformation and activity of methylated quinolines, a class of environmentally relevant N-heterocycles that are no native ligands of the estrogen receptor (ER), in the estrogen-responsive cell line ERα CALUX. We found that this widely used cell line overexpresses AOXs and NMTs while having low expression of CYP enzymes. Exposure of ERα CALUX cells to quinolines resulted in estrogenic effects, which could be mitigated using an inhibitor of AOX/NMTs. No such mitigation occurred after coexposure to a CYP1A inhibitor. A number of N-methylated but no hydroxylated transformation products were detected using liquid chromatography–mass spectrometry, which indicated that biotransformations to estrogenic metabolites were likely catalyzed by NMTs. Compared to the natural ER ligand 17β-estradiol, the products formed during the metabolization of quinolines were weak to moderate agonists of the human ERα. Our findings have potential implications for the risk assessment of these compounds and indicate that care must be taken when using in vitro estrogenicity assays, for example, ERα CALUX, for the characterization of N-heterocycles or environmental samples that may contain them.Item A rapid and sensitive fluorometric method for determination of aldehyde oxidase activity(Elsevier, 2018) Apenova, Nancy; Peng, Hui; Hecker, Markus; Brinkmann, MarkusPrevious research has characterized the important role of aldehyde oxidases (AOX) in biotransformation of N-heterocyclic therapeutic drugs and environmental contaminants in mammals. Research pertaining to AOX activity in non-mammalian vertebrates, however, is scarce, despite its biological role as a potentially important metabolic pathway for xenobiotics. One of the limiting factors of research on AOX is that available photometric methods are relatively insensitive, limited in throughput, and prone to cross-reactivity from other enzymes. Therefore, this study aimed to develop a novel and improved fluorometric AOX assay. This assay is based on the conversion of the exogenous aldehyde substrate 4-(dimethyl)amino cinnamaldehyde to its corresponding fluorescent acid by AOX, and was evaluated using partially purified hepatic cytosol from rat, human, and rainbow trout. Purification of native cytosol by heat treatment and ammonium sulfate precipitation resulted in increased specific activity of AOX. Michaelis-Menten kinetic parameters (Km and Vmax) were comparable to values previously generated by photometric methods. Furthermore, effects of the inhibitor hydralazine on AOX activity revealed half maximal inhibitory concentrations comparable to those generated using conventional methods. Product identity was confirmed by liquid chromatography and mass spectrometry. In summary, this study successfully developed a rapid and sensitive assay for determination of AOX activity in across different vertebrate species that is 4- to 10-fold more sensitive compared to conventional absorbance-based methods. It can be applied in environmental, toxicological, and pharmacological studies relating to identification of AOX substrates, as well as the induction of AOX expression through drugs and environmental contaminants.Item Above- and Below-Ground Carbon Sequestration in Shelterbelt Trees in Canada: A Review(MDPI, 2019) Mayrinck, Rafaella; Laroque, Colin; Amichev, Beyhan; Rees, Ken VanShelterbelts have been planted around the world for many reasons. Recently, due to increasing awareness of climate change risks, shelterbelt agroforestry systems have received special attention because of the environmental services they provide, including their greenhouse gas (GHG) mitigation potential. This paper aims to discuss shelterbelt history in Canada, and the environmental benefits they provide, focusing on carbon sequestration potential, above- and below-ground. Shelterbelt establishment in Canada dates back to more than a century ago, when their main use was protecting the soil, farm infrastructure and livestock from the elements. As minimal-and no-till systems have become more prevalent among agricultural producers, soil has been less exposed and less vulnerable to wind erosion, so the practice of planting and maintaining shelterbelts has declined in recent decades. In addition, as farm equipment has grown in size to meet the demands of larger landowners, shelterbelts are being removed to increase efficiency and machine maneuverability in the field. This trend of shelterbelt removal prevents shelterbelt’s climate change mitigation potential to be fully achieved. For example, in the last century, shelterbelts have sequestered 4.85 Tg C in Saskatchewan. To increase our understanding of carbon sequestration by shelterbelts, in 2013, the Government of Canada launched the Agricultural Greenhouse Gases Program (AGGP). In five years, 27 million dollars were spent supporting technologies and practices to mitigate GHG release on agricultural land, including understanding shelterbelt carbon sequestration and to encourage planting on farms. All these topics are further explained in this paper as an attempt to inform and promote shelterbelts as a climate change mitigation tool on agricultural lands.Item Green Spaces with Fewer People Improve Self-Reported Affective Experience and Mood(MDPI, 2023) Honey-Rosés, Jordi; Zapata, OscarCalm and quiet green spaces provide health benefits for urban residents. Yet as cities become more densely populated, increasing public users to green spaces may reduce or moderate these benefits. We examine how increased pedestrian density in a green street changes self-reported wellbeing. We use a between subject experimental design that added public users as confederates in randomly selected periods over three weeks. We collect data on mood and affective response from pedestrians moving through the green street (n = 504), with and without our public user treatment in randomly selected periods. Mood and affective response are improved when experiencing the green street with fewer people. We find that an increased number of public users in the green space has a negative effect on mood, especially among women. We provide experimental evidence that self-reported wellbeing in urban green spaces depends on social context, and that there are gender inequities associated with changes in affective response. Although we only measure immediate impacts, our results imply that the health benefits of green spaces may be limited by the total number of users. This research contributes additional evidence that greener cities are also healthier cities, but that the benefits may not be equally shared between women and men and will depend on the social context of use.Item Synthesis of magnetic metalorganic framework (MOF) for efficient removal of organic dyes from water(Nature Portfolio, 2015) Zhao, Xiaoli; Liu, Shuangliu; Tang, Zhi; Niu, Hongyun; Cai, Yaqi; Meng, Wei; Wu, Fengchang; Giesy, JohnA novel, simple and efficient strategy for fabricating a magnetic metal-organic framework (MOF) as sorbent to remove organic compounds from simulated water samples is presented and tested for removal of methylene blue (MB) as an example. The novel adsorbents combine advantages of MOFs and magnetic nanoparticles and possess large capacity, low cost, rapid removal and easy separation of the solid phase, which makes it an excellent sorbent for treatment of wastewaters. The resulting magnetic MOFs composites (also known as MFCs) have large surface areas (79.52 m2 g−1), excellent magnetic response (14.89 emu g−1), and large mesopore volume (0.09 cm3 g−1), as well as good chemical inertness and mechanical stability. Adsorption was not drastically affected by pH, suggesting π-π stacking interaction and/or hydrophobic interactions between MB and MFCs. Kinetic parameters followed pseudo-second-order kinetics and adsorption was described by the Freundlich isotherm. Adsorption capacity was 84 mg MB g−1 at an initial MB concentration of 30 mg L−1, which increased to 245 mg g−1 when the initial MB concentration was 300 mg L−1. This capacity was much greater than most other adsorbents reported in the literature. In addition, MFC adsorbents possess excellent reusability, being effective after at least five consecutive cycles.
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