Publications by authors named "Andrew Heyes"

To protect the integrity of sport, and the health of athletes, global anti-doping programmes seek to prevent doping, and elicit anti-doping and clean sport behaviours, through education, deterrence, detection, enforcement, and rules. To guide programme development, this meta-synthesis of qualitative research applied a behavioural science framework to identify barriers and enablers to doping, anti-doping, and clean sport. A systematic search of electronic databases up to May 2022, followed by critical appraisal, resulted in 73 included articles.

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Background: Although athletes seem to hold uniform views towards non-dopers, their perception of dopers is more nuanced, reflecting positive and negative attributes. Research also indicates that rarely a single factor can explain doping, but a host of reasons that intertwine. A holistic understanding of how values play a role in decisions in anti-doping and the elements that influence athletes' doping vulnerability is timely and warranted.

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Anthropogenic releases of mercury (Hg) are a human health issue because the potent toxicant methylmercury (MeHg), formed primarily by microbial methylation of inorganic Hg in aquatic ecosystems, bioaccumulates to high concentrations in fish consumed by humans. Predicting the efficacy of Hg pollution controls on fish MeHg concentrations is complex because many factors influence the production and bioaccumulation of MeHg. Here we conducted a 15-year whole-ecosystem, single-factor experiment to determine the magnitude and timing of reductions in fish MeHg concentrations following reductions in Hg additions to a boreal lake and its watershed.

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Food webs in urban estuaries support valuable ecosystem services that are subject to a wide range of stressors that can degrade the structure of trophic networks. Multiple trophic pathways stabilize food webs by providing complementary diet resources for consumers but the consequences of urbanization on estuarine food webs are relatively unknown. In estuarine creeks across an urban-to-suburban gradient, we demonstrate trophic decoupling of benthic and pelagic pathways, trophic niche contraction, and increasing human health risk arising with the same factors that are associated with ecological degradation.

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Coral reefs are impacted by a variety of anthropogenic stressors including inputs of chemical contaminants. Although data is currently limited, sunscreens containing ultraviolet (UV) filters have recently been suggested as an emerging class of chemical contaminants. To provide further data on the toxicity of the UV filter oxybenzone (benzophenone-3 or BP-3) to corals, we conducted three independent acute toxicity tests exposing the colonial stony coral Galaxea fascicularis to BP-3 (0.

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There has been a rapid increase in public, political, and scientific interest regarding the impact of organic ultraviolet (UV) filters to coral reefs. Such filters are found in sunscreens and other consumer products and enter the aquatic environment via direct (i.e.

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To better understand the transformation and photochemical fate of PAHs in aquatic environments, a custom-designed closed-circuit recirculation photodegradation system, combined with inline semi-continuous fluorescence and absorbance measurements, as well as modelling of excitation-emission (EEM) measurements with parallel factor analysis (PARAFAC), and GC-MS analysis, were combined to create a robust tool for holistically assessing the photodegradation of individual PAHs, their mixtures and photoproduct formation. Selected compounds included in the US EPA priority list, representing 2- to 6-ring compounds, were monitored individually and in mixtures, during 24 h photodegradation experiments. Experiments were conducted in solutions simulating ideal (ultrapure water) and environmentally relevant conditions (1.

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Article Synopsis
  • The study analyzed 13 UV-filters and 11 hormones in seawater, sediment, and coral tissues at 19 sites in Oahu, Hawaii, finding at least eight UV-filters present in all three environments.
  • The concentrations of UV-filters were generally low, with the highest concentrations observed at Waikiki beach, but minimal levels of hormones were detected, with most concentrations being below quantifiable limits.
  • The findings highlight the presence of UV-filters in coral tissue for the first time in U.S. coastal waters and will help inform future risk assessments regarding their impact on coral reefs.
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Sulfate reduction plays an important role in altering dissolved organic matter (DOM) in estuarine and coastal sediments, although its role in the production of optically active chromophoric DOM (CDOM) and a subset of fluorescent DOM (FDOM) has not been previously investigated in detail. Freshwater sediment slurries were incubated anaerobically with added sulfate and acetate to promote sulfate-reducing bacteria. Ultraviolet visible (UV-Vis) absorbance and 3-dimensional excitation emission matrix (EEM) fluorescence spectra were measured over a five weeks anaerobic dark incubation period.

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  • Recent advances allowed for simultaneous measurements of gas velocity and temperature using thermographic phosphors, employing continuous wave excitation and a two-colour intensity ratio for temperature assessment.
  • The paper introduces an alternative method based on the temperature-dependence of luminescence lifetime, using phase-shift analysis from single BaMgAlO:Eu phosphor particles.
  • This new method shows low interference from other signals and offers precise measurements of gas temperature, achieving an accuracy of 8.6 K at temperatures above 700 K.
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Larval gray tree frogs (Hyla chrysoscelis) were exposed to inorganic Se (SeO) added to the diet (10.2 and 86.3 ug/g dw) and monitored for accumulation and effect.

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We propose a point measurement technique for simultaneous gas temperature and velocity measurement based on thermographic phosphor particles dispersed in the fluid. The flow velocity is determined from the frequency of light scattered by BaMgAl10O17:Eu2+ phosphor particles traversing the fringes like in conventional laser Doppler velocimetry. Flow temperatures are derived using a two-color ratio method applied to the phosphorescence from the same particles.

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An extensively diverse array of brominated disinfection byproducts (DBPs) were generated following electrochemical disinfection of natural coastal/estuarine water, which is one of the main treatment methods currently under consideration for ballast water treatment. Ultra-high-resolution mass spectrometry revealed 462 distinct brominated DBPs at a relative abundance in the mass spectra of more than 1%. A brominated DBP with a relative abundance of almost 22% was identified as 2,2,4-tribromo-5-hydroxy-4-cyclopentene-1,3-dione, which is an analogue to several previously described 2,2,4-trihalo-5-hydroxy-4-cyclopentene-1,3-diones in drinking water.

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The concentration of 51 parent and alkylated PAHs was examined in oysters, Ostrea equestris, and corals, Tubastrea coccinea, collected from oil-rig structures off the coast of Louisiana during April and May 2011 to investigate their potential use as monitors for offshore contamination events. Corals and oysters collected from both sampling trips had lower PAH accumulation than most bivalves collected in previous studies near the shoreline of Louisiana and elsewhere in the Gulf of Mexico. In April, total PAH (TPAH) concentrations ranged from 8.

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Maternal transfer of methylmercury (MeHg) to eggs is an important exposure pathway for developing offspring. However, our understanding of this process is limited, particularly in estuarine fish. We conducted a 91-day chronic laboratory exposure of Cyprinodon variegatus to four concentrations of dietary MeHg ranging from 0.

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The fate of mercury (Hg) deposited on forested upland soils depends on a wide array of biogeochemical and hydrological processes occurring in the soil landscape. In this study, Hg in soil, soilwater, and streamwater were measured across a forested upland subcatchment of the METAALICUS watershed in northwestern Ontario, Canada, where a stable Hg isotope (spike Hg) was applied to distinguish newly deposited Hg from Hg already resident in the watershed (ambient Hg). In total, we were able to account for 45% of the total mass of spike Hg applied to the subcatchment during the entire loading phase of the experiment, with approximately 22% of the total mass applied now residing in the top 15 cm of the mineral soil layer.

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We performed an experiment in which larval gray tree frogs (Hyla chrysoscelis) were raised through metamorphosis on diets increased with a suite of elements associated with coal combustion residues (silver [Ag], arsenic [As], cadmium [Cd], chromium [Cr], copper [Cu], mercury [Hg], lead [Pb], selenium [Se], vanadium [V], and zinc [Zn]) at "low" and "high" concentrations. We quantified accumulation of metals at three life stages (mid-larval development, initiation of metamorphosis, and completion of metamorphosis) as well as effects on survival, metabolic rate, size at metamorphosis, and duration and loss of weight during metamorphosis. Most elements were accumulated in a dose-dependent pattern by some or all life stages, although this was not the case for Hg.

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Dietary methylmercury (MeHg) uptake by fish in relation to life stage, species, and level of exposure is poorly understood in lower trophic levels, particularly in estuarine species. The authors compared accumulation of dietary MeHg as well as sensitivity (survival and growth) to dietary MeHg exposure in two species of estuarine forage fish, Cyprinodon variegatus and Menidia beryllina. Fish were fed one of five dietary MeHg concentrations (ranging from 0.

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Article Synopsis
  • Selenium is an essential micronutrient with a narrow safe range, and its toxicity increases when transformed into organic forms like selenomethionine, especially in aquatic food chains.
  • A study focused on Cope's gray tree frogs revealed that high doses of selenomethionine resulted in 100% mortality, while a low dose decreased survival and caused deformities during metamorphosis.
  • Resource limitations from feeding regimens affected toxicity levels, but the low dose still significantly impacted growth and tissue selenium levels in metamorphosed frogs.
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  • The paper introduces an innovative optical diagnostic method using seeded thermographic phosphor particles for simultaneous measurements of gas temperature, velocity, and mixture fraction in turbulent flows.
  • The technique utilizes particle Mie scattering for velocity determination through a traditional PIV method, while phosphorescence emission helps measure temperature with a two-color approach, confirming that small tracer particle temperatures reflect gas temperatures.
  • The experimental results demonstrate the method's effectiveness in measuring these parameters in a turbulent jet at up to 700 K, achieving high precision (2-5%) and accuracy (2%).
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  • Selenium (Se) and vanadium (V) are contaminants found in aquatic systems from fossil fuel waste, and their effects on gray tree frogs were studied during their larval to metamorphic stages.
  • Despite bioaccumulation of both metals, the study found no negative effects on frog growth, survival, or metabolism.
  • Distinct differences were observed in how the two metals were accumulated and eliminated, with frogs accumulating less V after metamorphosis compared to those exposed to Se, which remained in the frogs’ bodies even during metamorphosis.
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  • Methylmercury bioaccumulation in marine food webs poses significant threats to fish-eating species and humans, particularly in the Bay of Fundy, Canada.
  • A new mercury cycling model indicates that water from rivers and tides is the main source of methylmercury in this region, as sediment methylation is offset by rapid demethylation.
  • Despite a historical decline in water column methylmercury levels, sediment concentrations continue to rise due to legacy mercury, suggesting that benthic organisms will experience increasing mercury levels for decades to come, even with reduced mercury inputs from industry.
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Vanadium (V) exerts a variety of effects related to metabolic function in vertebrates, including modifying glycolytic pathways and lipid metabolism. However, little is known about toxicity of V to wildlife in natural systems. We conducted parallel, independent studies to evaluate the effect of dietary exposure to vanadium on survival, metabolism, growth, and lipid storage of larval leopard frogs (Rana sphenocephala).

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Article Synopsis
  • Methylmercury from industrial emissions harms humans and wildlife, complicating the understanding of fish mercury levels due to historical contamination.
  • A whole-ecosystem experiment was conducted where stable mercury isotopes were added to a lake to measure the direct impact on fish contamination.
  • Results showed fish methylmercury levels rose quickly from lake deposition, indicating that while reductions in mercury emissions will lead to faster declines in fish contamination, full recovery will take longer due to lingering mercury stored in watersheds.
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