39 results on '"Maisonneuve, F."'
Search Results
2. Efficient boundary surface reconstruction from multi-label volumetric data with mathematical morphology
- Author
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NGuyen, F., primary, Kanit, T., additional, Maisonneuve, F., additional, and Imad, A., additional
- Published
- 2023
- Full Text
- View/download PDF
3. Extensive study of HD 25558, a long-period double-lined binary with two SPB components
- Author
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Sódor, Á., De Cat, P., Wright, D. J., Neiner, C., Briquet, M., Lampens, P., Dukes, R. J., Henry, G. W., Williamson, M. H., Brunsden, E., Pollard, K. R., Cottrell, P. L., Maisonneuve, F., Kilmartin, P. M., Matthews, J., Kallinger, T., Beck, P. G., Kambe, E., Engelbrecht, C. A., Czanik, R. J., Yang, S., Hashimoto, O., Honda, S., Fu, J. N., Castanheira, B., Lehmann, H., Bognár, Zs., Behara, N., Scaringi, S., Van Winckel, H., Menu, J., Lobel, A., Mathias, P., Saesen, S., Vučković, M., and collaboration, the MiMeS
- Subjects
Astrophysics - Solar and Stellar Astrophysics - Abstract
We carried out an extensive observational study of the Slowly Pulsating B (SPB) star, HD 25558. The ~2000 spectra obtained at different observatories, the ground-based and MOST satellite light curves revealed that this object is a double-lined spectroscopic binary with an orbital period of about 9 years. The observations do not allow the inference of an orbital solution. We determined the physical parameters of the components, and found that both lie within the SPB instability strip. Accordingly, both show line-profile variations due to stellar pulsations. Eleven independent frequencies were identified in the data. All the frequencies were attributed to one of the two components based on Pixel-by-pixel variability analysis of the line profiles. Spectroscopic and photometric mode identification was also performed for the frequencies of both stars. These results suggest that the inclination and rotation of the two components are rather different. The primary is a slow rotator with ~6 d period, seen at ~60 deg inclination, while the secondary rotates fast with ~1.2 d period, and is seen at ~20 inclination. Spectropolarimetric measurements revealed that the secondary component has a magnetic field with at least a few hundred Gauss strength, while no magnetic field can be detected in the primary., Comment: 24 pages, 12 figures, 11 tables. Accepted for publication in MNRAS
- Published
- 2013
- Full Text
- View/download PDF
4. Spectroscopic mode identification of main-sequence non-radially pulsating stars
- Author
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Maisonneuve, F., Pollard, K. R., Cottrell, P. L., Kilmartin, P. M., Wright, D. J., and De Cat, P.
- Published
- 2010
- Full Text
- View/download PDF
5. Spectroscopic mode identification of main-sequence non-radially pulsating stars
- Author
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Maisonneuve, F., primary, Pollard, K. R., additional, Cottrell, P. L., additional, Kilmartin, P. M., additional, Wright, D. J., additional, and De Cat, P., additional
- Published
- 2009
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- View/download PDF
6. Assessment of Sublethal Effects of Neonicotinoid Insecticides on the Life‐History Traits of 2 Frog Species
- Author
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Robinson, S.A., primary, Richardson, S.D., additional, Dalton, R.L., additional, Maisonneuve, F., additional, Bartlett, A.J., additional, Solla, S.R., additional, Trudeau, V.L., additional, and Waltho, N., additional
- Published
- 2019
- Full Text
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7. Extensive spectroscopic and photometric study of HD 25558, a long orbital-period binary with two SPB components
- Author
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Sódor, Á., de Cat, Peter, Wright, D. J., Neiner, Coralie, Briquet, Maryline, Dukes, R. J., Fekel, Francis, Henry, G. W., Williamson, M. H., Muterspaugh, M. W., Brunsden, E., Pollard, Karen R., Cottrell, P. L., Maisonneuve, F., Kilmartin, P. M., Matthews, Jaymie M., Kallinger, Thomas, Beck, P. G., Kambe, Eiji, Engelbrecht, C. A., Czanik, R. J., Yang, S., Hashimoto, O., Honda, S., Fu, J.-N., Castanheira, B. G., Lehmann, H., Behara, Natalie, van Winckel, H., Scaringi, S., Menu, Jonathan, Lobel, Alex, Lampens, P., Mathias, P., Chaplin, William J., Handler, Gerald, Pigulski, Andrzej, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Etoile, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
- Subjects
[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] - Abstract
International audience
- Published
- 2013
8. Extensive study of HD 25558, a long-period double-lined binary with two SPB components
- Author
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Sódor, Á., De Cat, Peter, Wright, David, Neiner, Coralie, Briquet, Maryline, Lampens, Patricia, Dukes, Robert, Henry, Gregory W., Williamson, Michael, Brunsden, E., Pollard, Karen, Cottrell, Peter, Maisonneuve, F., Kilmartin, Pam, Matthews, Jaymie, Kallinger, Thomas, Beck, Paul, Kambe, Eiji, Engelbrecht, Chris, Czanik, R.J., Yang, Stephenson, Hashimoto, Osamu, Honda, Satoshi, Fu, J.N., Castanheira, Bárbara Garcia, Lehmann, Holger, Bognár, Zs, Behara, Natalie Thérèse, Scaringi, Simone, Van Winckel, Hans, Menu, Jonathan, Lobel, Alex, Mathias, Ph, Saesen, Sophie, Vučković, Maja, Sódor, Á., De Cat, Peter, Wright, David, Neiner, Coralie, Briquet, Maryline, Lampens, Patricia, Dukes, Robert, Henry, Gregory W., Williamson, Michael, Brunsden, E., Pollard, Karen, Cottrell, Peter, Maisonneuve, F., Kilmartin, Pam, Matthews, Jaymie, Kallinger, Thomas, Beck, Paul, Kambe, Eiji, Engelbrecht, Chris, Czanik, R.J., Yang, Stephenson, Hashimoto, Osamu, Honda, Satoshi, Fu, J.N., Castanheira, Bárbara Garcia, Lehmann, Holger, Bognár, Zs, Behara, Natalie Thérèse, Scaringi, Simone, Van Winckel, Hans, Menu, Jonathan, Lobel, Alex, Mathias, Ph, Saesen, Sophie, and Vučković, Maja
- Abstract
We carried out an extensive observational study of the Slowly Pulsating B (SPB) star, HD 25558. The ≈2000 spectra obtained at different observatories, the ground-based and MOST satellite light curves revealed that this object is a double-lined spectroscopic binary with an orbital period of about nine years. The observations do not allow the inference of an orbital solution. We determined the physical parameters of the components, and found that both lie within the SPB instability strip. Accordingly, both show line-profile variations due to stellar pulsations. 11 independent frequencies were identified in the data. All the frequencies were attributed to one of the two components based on pixel-by-pixel variability analysis of the line profiles. Spectroscopic and photometric mode identification was also performed for the frequencies of both stars. These results suggest that the inclination and rotation of the two components are rather different. The primary is a slow rotator with ≈6 d period, seen at ≈60° inclination, while the secondary rotates fast with ≈1.2 d period, and is seen at ≈20° inclination. Spectropolarimetric measurements revealed that the secondary component has a magnetic field with at least a few hundred Gauss strength, while no magnetic field can be detected in the primary. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society., SCOPUS: ar.j, info:eu-repo/semantics/published
- Published
- 2014
9. Efficient boundary surface reconstruction from multi-label volumetric data with mathematical morphology.
- Author
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N'Guyen, Franck, Kanit, Toufik, Maisonneuve, F., and Imad, Abdellatif
- Subjects
- *
MATHEMATICAL morphology , *SURFACE reconstruction , *LEANNESS , *CUBES , *AMBIGUITY - Abstract
This paper proposes a new, fully automatic and robust approach to generating triangular meshes directly from volumetric data (scanned images), particularly when these images contain multiple adjacent labels. Current meshing techniques produce a number of mesh elements directly related to the number of components (voxels) in the image. This number can be considerable if the image is large. The proposed methodology is significantly less dense in terms of the number of elements compared to marching cube methods. The proposed method presents no configuration ambiguity and is faithful to the original morphology of the images regardless of the thinness of the topologies or the presence of possible erratic morphological configurations that may lead to geometric interpretation indecisions. [Display omitted] • New fully automatic and robust approach to generate triangular meshes directly from volumetric data, in particular when these images contain adjoining multiple-label. • The proposed methodology is significantly less dense in terms of the number of elements compared to Marching Cube Methods. • The proposed method presents no configuration ambiguity and is faithful to the original morphology of the images regardless of the thinness of the topologies or the presence of possible erratic morphological configurations that may lead to geometric interpretation indecisions. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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10. Extensive spectroscopic and photometric study of HD 25558, a long orbital-period binary with two SPB components
- Author
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Sódor, Á., primary, De Cat, P., additional, Wright, D. J., additional, Neiner, C., additional, Briquet, M., additional, Dukes, R. J., additional, Fekel, F. C., additional, Henry, G. W., additional, Williamson, M. H., additional, Muterspaugh, M. W., additional, Brunsden, E., additional, Pollard, K. R., additional, Cottrell, P. L., additional, Maisonneuve, F., additional, Kilmartin, P. M., additional, Matthews, J. M., additional, Kallinger, T., additional, Beck, P. G., additional, Kambe, E., additional, Engelbrecht, C. A., additional, Czanik, R. J., additional, Yang, S., additional, Hashimoto, O., additional, Honda, S., additional, Fu, J.-N., additional, Castanheira, B., additional, Lehmann, H., additional, Behara, N., additional, Van Winckel, H., additional, Scaringi, S., additional, Menu, J., additional, Lobel, A., additional, Lampens, P., additional, and Mathias, P., additional
- Published
- 2013
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11. Frequency analysis and pulsational mode identification of two γ Doradus stars: HD 40745 and HD 189631★
- Author
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Maisonneuve, F., primary, Pollard, K. R., additional, Cottrell, P. L., additional, Wright, D. J., additional, De Cat, P., additional, Mantegazza, L., additional, Kilmartin, P. M., additional, Suárez, J. C., additional, Rainer, M., additional, and Poretti, E., additional
- Published
- 2011
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12. Is HD 147787 a double-lined binary with two pulsating components? Preliminary results from a spectroscopic multi-site campaign
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De Cat, P., primary, Wright, D. J., additional, Pollard, K. R., additional, Maisonneuve, F., additional, Kilmartin, P. M., additional, Laney, D., additional, Guzik, Joyce Ann, additional, and Bradley, Paul A., additional
- Published
- 2009
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13. Spectroscopic Mode-Identification of γ Doradus Stars
- Author
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Maisonneuve, F., primary, Pollard, K. R., additional, Cottrell, P. L., additional, Kilmartin, P. M., additional, Wright, D. J., additional, De Cat, P., additional, Guzik, Joyce Ann, additional, and Bradley, Paul A., additional
- Published
- 2009
- Full Text
- View/download PDF
14. Towards asteroseismology of main-sequence g-mode pulsators: spectroscopic multi-site campaigns for slowly pulsating B stars and γ Doradus stars
- Author
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De Cat, P., primary, Wright, D. J., additional, Pollard, K. R., additional, Maisonneuve, F., additional, Kilmartin, P. M., additional, Lehmann, H., additional, Yang, S., additional, Kambe, E., additional, Saesen, S., additional, Carrier, F., additional, Mkrtichian, D., additional, Mantegazza, L., additional, Rainer, M., additional, Poretti, E., additional, Laney, D., additional, Fu, J. N., additional, Guzik, Joyce Ann, additional, and Bradley, Paul A., additional
- Published
- 2009
- Full Text
- View/download PDF
15. Results from Classification Observations and a Multi-site Campaign on γ Doradus and SPB Type Stars
- Author
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Wright, D. J., primary, De Cat, P., additional, Pollard, K. R., additional, Maisonneuve, F., additional, Kilmartin, P. M., additional, Telting, J. H., additional, Kambe, E., additional, Poretti, E., additional, Lehmann, H., additional, Yang, S., additional, Mkrtichian, D., additional, Laney, D., additional, Fu, J. N., additional, Guzik, Joyce Ann, additional, and Bradley, Paul A., additional
- Published
- 2009
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16. Geodesic methods in quantitative image analysis
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Lantuejoul, C., primary and Maisonneuve, F., additional
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- 1984
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17. Geodesic methods in quantitative image analysis
- Author
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Lantuejoul, C., primary and Maisonneuve, F., additional
- Published
- 1983
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18. Milkweed in agricultural field margins - A neonicotinoid exposure route for pollinators at multiple life stages.
- Author
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Naujokaitis-Lewis I, Endicott S, Gaudreault E, Maisonneuve F, and Robinson SA
- Subjects
- Animals, Ontario, Environmental Monitoring, Pollination, Plant Leaves chemistry, Asclepias, Flowers, Neonicotinoids analysis, Insecticides analysis, Agriculture
- Abstract
Neonicotinoid insecticides move from targeted crops to wildflowers located in adjacent field margins, acting as a potential exposure source for wild pollinators and insect species of conservation concern, including monarch butterflies. Monarchs rely on milkweed over multiple life stages, including as a host plant for eggs and a food source for both larvae (leaves) and adults (flowers). Milkweeds, which are closely associated with field margins, can contain neonicotinoid residues, but previous assessments are constrained to a single plant tissue type. In 2017 and 2018, we sampled milkweeds from 95 field margins adjacent to crop fields (corn, soybean, hay, wheat, and barley) in agricultural landscapes of eastern Ontario, Canada. Milkweeds were sampled during the flower blooming period and leaves and flower tissues were analysed. The neonicotinoids acetamiprid, clothianidin, thiamethoxam, and thiacloprid were detected. Maximum concentrations in leaf samples included 10.30 ng/g of clothianidin in 2017, and 24.4 ng/g of thiamethoxam in 2018. Clothianidin and thiamethoxam percent detections in flowers (72 % and 61 %, respectively) were significantly higher than detections in leaves (24 % and 31 %, respectively). Thiamethoxam concentrations were significantly higher in paired flower samples than leaf samples (median 0.33 ng/g vs <0.07 ng/g) while clothianidin concentrations also trended higher in flowers (median 0.18-0.55 ng/g vs <0.18 ng/g). Only thiamethoxam showed significant differences between years, and we found no effect of crop type, with hay, soybean and corn fields all yielding 50-56 % detections in leaves. We found significantly higher concentrations in older milkweed flowers than young flowers or leaves (medians 0.87 ng/g vs <0.18 ng/g and 0.45 ng/g vs <0.07 ng/g for clothianidin and thiamethoxam, respectively). Our results highlight the importance of considering variation in milkweed tissue type and age of flowers in neonicotinoid exposure risk assessments. Efforts to increase milkweed availability in agricultural landscapes should consider how exposure to neonicotinoids can be mitigated., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2024. Published by Elsevier B.V. All rights reserved.)
- Published
- 2024
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19. Exposure to PM 2.5 modulate the pro-inflammatory and interferon responses against influenza virus infection in a human 3D bronchial epithelium model.
- Author
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Chivé C, Martίn-Faivre L, Eon-Bertho A, Alwardini C, Degrouard J, Albinet A, Noyalet G, Chevaillier S, Maisonneuve F, Sallenave JM, Devineau S, Michoud V, Garcia-Verdugo I, and Baeza-Squiban A
- Subjects
- Humans, Interferons, Respiratory Mucosa, Antiviral Agents, Epithelium metabolism, Particulate Matter toxicity, Influenza, Human genetics, Influenza, Human metabolism, Virus Diseases, Orthomyxoviridae
- Abstract
Epidemiological studies showed a positive association between exposure to PM
2.5 and the severity of influenza virus infection. However, the mechanisms by which PM2.5 can disrupt antiviral defence are still unclear. From this perspective, the objective of this study was to evaluate the effects of PM2.5 on antiviral signalling in the respiratory epithelium using the bronchial Calu-3 cell line grown at the air-liquid interface. Pre-exposure to PM2.5 before infection with the influenza virus was investigated, as well as a co-exposure. Although a physical interaction between the virus and the particles seems possible, no effect of PM2.5 on viral replication was observed during co-exposure, although a downregulation of IFN-β release was associated to PM2.5 exposure. However, pre-exposure slightly increased the viral nucleoprotein production and the pro-inflammatory response. Conversely, the level of the myxovirus resistance protein A (MxA), an interferon-stimulated gene (ISG) induced by IFN-β, was reduced. Therefore, these results suggest that pre-exposure to PM2.5 could alter the antiviral response of bronchial epithelial cells, increasing their susceptibility to viral infection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
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20. Anticoagulant Rodenticide Toxicity in Terrestrial Raptors: Tools to Estimate the Impact on Populations in North America and Globally.
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Elliott JE, Silverthorn V, English SG, Mineau P, Hindmarch S, Thomas PJ, Lee S, Bowes V, Redford T, Maisonneuve F, and Okoniewski J
- Subjects
- Animals, 4-Hydroxycoumarins poisoning, 4-Hydroxycoumarins toxicity, Canada, Environmental Monitoring, Rodenticides toxicity, Anticoagulants toxicity, Anticoagulants poisoning, Raptors
- Abstract
Anticoagulant rodenticides (ARs) have caused widespread contamination and poisoning of predators and scavengers. The diagnosis of toxicity proceeds from evidence of hemorrhage, and subsequent detection of residues in liver. Many factors confound the assessment of AR poisoning, particularly exposure dose, timing and frequency of exposure, and individual and taxon-specific variables. There is a need, therefore, for better AR toxicity criteria. To respond, we compiled a database of second-generation anticoagulant rodenticide (SGAR) residues in liver and postmortem evaluations of 951 terrestrial raptor carcasses from Canada and the United States, 1989 to 2021. We developed mixed-effects logistic regression models to produce specific probability curves of the toxicity of ∑SGARs at the taxonomic level of the family, and separately for three SGARs registered in North America, brodifacoum, bromadiolone, and difethialone. The ∑SGAR threshold concentrations for diagnosis of coagulopathy at 0.20 probability of risk were highest for strigid owls (15 ng g
-1 ) lower and relatively similar for accipitrid hawks and eagles (8.2 ng g-1 ) and falcons (7.9 ng g-1 ), and much lower for tytonid barn owls (0.32 ng g-1 ). These values are lower than those we found previously, due to compilation and use of a larger database with a mix of species and source locations, and also to refinements in the statistical methods. Our presentation of results on the family taxonomic level should aid in the global applicability of the numbers. We also collated a subset of 440 single-compound exposure events and determined the probability of SGAR-poisoning symptoms as a function of SGAR concentration, which we then used to estimate relative SGAR toxicity and toxic equivalence factors: difethialone, 1, brodifacoum, 0.8, and bromadiolone, 0.5. Environ Toxicol Chem 2024;43:988-998. © 2024 His Majesty the King in Right of Canada and The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC Reproduced with the permission of the Minister of Environment and Climate Change Canada., (© 2024 His Majesty the King in Right of Canada and The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC Reproduced with the permission of the Minister of Environment and Climate Change Canada.)- Published
- 2024
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21. The cost of protecting resources: a cross-sectional study on the interaction between LMX and role ambiguity on work addiction and burnout among Canadian first-level healthcare managers.
- Author
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Maisonneuve F, Groulx P, Galy A, Chênevert D, and Cossette M
- Abstract
Introduction: Using the conservation of resources (COR) theory, our study explores the interaction between role ambiguity and leader-member exchange (LMX) quality on burnout using work addiction as a mediator among Canadian first-level healthcare managers., Methods: Cross-sectional data was collected among 165 first-level managers working in healthcare with the support of interprofessional associations in Canada. Linear regression was used to test the presented hypotheses., Results: Work addiction fully mediated the positive relationship between role ambiguity and burnout among first-level managers. In addition, high LMX exacerbated both the direct and indirect effects of role ambiguity., Conclusion: Our study contributes by identifying role ambiguity as a context under which LMX can have adverse effects for first-level managers in healthcare. Moreover, work addiction acted as a mediator, theorized as a risky resource investment which depletes managers' resources. Having a good relationship with their team further entices managers to develop a pathological relationship with their work to protect its members, which in turn is related to higher levels of burnout., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Maisonneuve, Groulx, Galy, Chênevert and Cossette.)
- Published
- 2024
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22. The ripple effect of strain in times of change: how manager emotional exhaustion affects team psychological safety and readiness to change.
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Groulx P, Maisonneuve F, Harvey JF, and Johnson KJ
- Abstract
Introduction: Managers assume a pivotal role during periods of organizational change, yet there exists a notable gap in our understanding of how their emotional exhaustion may impact their capacity to generate readiness to change within their teams. Grounded in the conservation of resources theory (COR), this study explores the crossover effect of managers' emotional exhaustion on team readiness to change. We expect this to occur through higher levels of laissez-faire leadership, which impacts the teams' psychological safety., Methodology: Data was gathered within a Canadian governmental organization undergoing two significant changes-cultural change and digitalization-with a specific focus on leadership as a pivotal factor in preparing teams for change. Employing surveys from 372 team members and 62 managers affected by this change, we conducted path analysis to empirically test the proposed model across 74 teams and their respective managers., Results: Managers' emotional exhaustion has a negative indirect effect on team readiness to change. The double mediation pathway implies a positive relationship on laissez-faire leadership, which hinders psychological safety. In turn, psychological safety hampers team readiness to change., Conclusion: Managers must invest significant resources to fulfill their roles and responsibilities during strategic change. Those who feel exhausted during change may look for ways to protect some of their resources by reducing the time and energy they invest leading their team. This self-preserving resource strategy has detrimental consequences on teams' effectiveness during change due to an indirect crossover effect that affects the levels of psychological safety on the team., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Groulx, Maisonneuve, Harvey and Johnson.)
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- 2024
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23. Effects of ethical climate in association with tenure on work addiction, quality of care and staff retention: a cross-sectional study.
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Maisonneuve F, Groulx P, Chênevert D, Grady C, and Coderre-Ball A
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- Humans, Cross-Sectional Studies, Canada, Regression Analysis, Surveys and Questionnaires, Intention, Job Satisfaction, Health Personnel, Attitude of Health Personnel
- Abstract
Objectives: Work addiction is not contingent on personality alone; it is also impacted by social contextual factors. Work addiction influences the perceived quality of care and intention to remain in healthcare sector. The current study seeks to understand the role of ethical climate as a potential organisational lever to reduce such addiction, especially among newcomers., Design: We contacted a sample of Canadian healthcare organisations to collect quantitative data using an online questionnaire from November 2021 to February 2022. All constructs (ethical climate, work addiction, perceived quality of care, intention to quit the profession) were measured using validated psychometric scales. 860 respondents provided complete questionnaires. We analysed the data using structural equation modelling and regression analysis., Results: Work addiction mediated the indirect relationship between ethical climate and the intention to quit the profession (β=-0.053; 95% CI (-0.083 to -0.029); p<0.001) and with quality of care (β=0.049; 95% CI (0.028, 0.077); p<0.001). For each increase of 1 SD of ethical climate, the total effects regarding the variations in the outcomes were more important at low rather than high levels of tenure for work addiction (-11%, -2%), perceived quality of care (23%, 11%) and intention to quit the profession (-30%, -23%), respectively., Conclusion: Ethical climate in healthcare organisations has a significant and beneficial relationship with healthcare workers' (HCWs) work addiction behaviours. In turn, this relationship is related to greater perceived quality of care and higher intention to remain, especially for HCWs with lower tenure., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2023
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24. Perfluoroalkyl Substances in Seabird Eggs from Canada's Pacific Coast: Temporal Trends (1973-2019) and Interspecific Patterns.
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Kesic R, Elliott JE, Elliott KH, Lee SL, and Maisonneuve F
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- Animals, Environmental Monitoring, Birds, British Columbia, Alkanesulfonates, Carboxylic Acids, Fluorocarbons analysis, Charadriiformes, Alkanesulfonic Acids analysis
- Abstract
Whether perfluoroalkyl sulfonates (PFSAs) and perfluoroalkyl carboxylates (PFCAs) are responding to legislative restrictions and showing decreasing trends in top marine predators that range across the eastern North Pacific Ocean is unclear. Here, we examined longer-term temporal trends (1973-2019) of 4 PFSAs and 13 PFCAs, as well stable isotopes of δ
13 C and δ15 N, in the eggs of 4 seabird species sampled along a nearshore-offshore gradient; double-crested cormorants ( Nannopterum auritum ), pelagic cormorants ( Urile pelagicus ), rhinoceros auklets ( Cerorhinca monocerata ), and Leach's storm-petrels ( Hydrobates leucorhous ) from the Pacific coast of British Columbia, Canada. PFOS was the most abundant PFSA (79-94%) detected in all eggs regardless of colony and year, with the highest concentrations, on average, measured in auklet eggs (mean = 58 ng g-1 , range = 11-286 ng g-1 ww). Perfluoroundecanoic acid (PFUdA) and perfluorotridecanoic acid (PFTriDA) were the dominant long-chain PFCAs (≥30% combined). The majority of PFSAs (including PFOS) are statistically declining ( p < 0.001) in the eggs of all 4 species with PFOS half-lives ranging from 2.6 to 7.8 years. Concentrations of long-chain PFCAs exhibited a trajectory comprised of linear increases and second-order declines, suggesting that the rate of uptake of PFCAs is slowing or leveling off. These trends are consistent with the voluntarily ceased production of PFSAs by 3M circa 2000-2003 and are among the first from the northeast Pacific to indicate a positive response to several regulations and restrictions on PFCAs from facility emissions and product content.- Published
- 2023
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25. How do Informal Caregivers of Seniors' Tasks Lead to Presenteeism and Absenteeism Behaviors? A Canadian Quantitative Study.
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Beauchamp Legault MÈ, Chênevert D, Maisonneuve F, and Mansour S
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- Humans, Aged, Presenteeism, Cross-Sectional Studies, Canada, Surveys and Questionnaires, Caregivers psychology, Absenteeism
- Abstract
This study extends our knowledge on the role of informal caregivers of seniors and the impact of this role on presenteeism and absenteeism at work. Based on the conservation of resources theory, this article seeks to gain insights into the mechanisms and antecedents of presenteeism and absenteeism among employees who are also informal caregivers of seniors. Specifically, this article argues that family-work conflict and emotional exhaustion mediate the relationship between the informal caregiver's role, presenteeism, and absenteeism. Quantitative data (questionnaire) from this cross-sectional study were collected from 915 informal caregivers of seniors from 8 Canadian organizations. Structural equation modelling (SEM) was undertaken using IBM SPSS AMOS 28.0 to test all hypotheses. Informal caregivers of seniors who need to coordinate and organize healthcare are at a higher risk of experiencing family-work conflict. Family-work conflict experienced by informal caregivers subsequently leads to emotional exhaustion, presenteeism, and absenteeism. Because informal caregiving of seniors is likely to increase in coming years for many workers, organizations must be aware of the possible consequences of this role on work productivity. This study shows that not all tasks of informal caregivers of older adults lead to presenteeism and absenteeism through family-work conflict and emotional exhaustion. This study is innovative because, to our knowledge, no study of informal caregivers of older adults has examined the effect of different tasks in this role on presenteeism and absenteeism.
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- 2023
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26. Anticoagulant Rodenticide Contamination of Terrestrial Birds of Prey from Western Canada: Patterns and Trends, 1988-2018.
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Elliott JE, Silverthorn V, Hindmarch S, Lee S, Bowes V, Redford T, and Maisonneuve F
- Subjects
- Animals, Anticoagulants, British Columbia, Female, Rats, Raptors, Rodenticides analysis, Strigiformes
- Abstract
As the dominant means for control of pest rodent populations globally, anticoagulant rodenticides (ARs), particularly the second-generation compounds (SGARs), have widely contaminated nontarget organisms. We present data on hepatic residues of ARs in 741 raptorial birds found dead or brought into rehabilitation centers in British Columbia, Canada, over a 30-year period from 1988 to 2018. Exposure varied by species, by proximity to residential areas, and over time, with at least one SGAR residue detected in 74% of individuals and multiple residues in 50% of individuals. By comparison, we detected first-generation compounds in <5% of the raptors. Highest rates of exposure were in barred owls (Strix varia), 96%, and great horned owls (Bubo virginianus), 81%, species with diverse diets, including rats (Rattus norvegicus and Rattus rattus), and inhabiting suburban and intensive agricultural habitats. Barn owls (Tyto alba), mainly a vole (Microtus) eater, had a lower incidence of exposure of 65%. Putatively, bird-eating raptors also had a relatively high incidence of exposure, with 75% of Cooper's hawks (Accipiter cooperii) and 60% of sharp-shinned hawks (Accipiter striatus) exposed. Concentrations of SGARs varied greatly, for example, in barred owls, the geometric mean ∑SGAR = 0.13, ranging from <0.005 to 1.81 μg/g wet weight (n = 208). Barred owls had significantly higher ∑SGAR concentrations than all other species, driven by significantly higher bromadiolone concentrations, which was predicted by the proportion of residential land within their home ranges. Preliminary indications that risk mitigation measures implemented in 2013 are having an influence on exposure include a decrease in mean concentrations of brodifacoum and difethialone in barred and great horned owls and an increase in bromodialone around that inflection point. Environ Toxicol Chem 2022;41:1903-1917. © 2022 Her Majesty the Queen in Right of Canada. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Reproduced with the permission of the Minister of Environment and Climate Change Canada., (© 2022 Her Majesty the Queen in Right of Canada. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Reproduced with the permission of the Minister of Environment and Climate Change Canada.)
- Published
- 2022
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27. Neonicotinoid pesticides exert metabolic effects on avian pollinators.
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English SG, Sandoval-Herrera NI, Bishop CA, Cartwright M, Maisonneuve F, Elliott JE, and Welch KC Jr
- Subjects
- Animals, Male, Pollination, Toxicity Tests, Subacute, Birds metabolism, Neonicotinoids toxicity, Nitro Compounds toxicity, Pesticides toxicity
- Abstract
Neonicotinoids are neurotoxic systemic insecticides applied extensively worldwide. The impacts of common neonicotinoids like imidacloprid on non-target invertebrate pollinators have been widely studied, however effects on vertebrate pollinators have received little attention. Here, we describe the first study evaluating the effects of short-term (3 d) exposure to a range of environmentally relevant concentrations ([Formula: see text] to [Formula: see text]Body Weight) of imidacloprid on wild-caught ruby-throated hummingbirds. Within 2 h of exposure, hummingbirds exhibited a significant depression in energy expenditure (up to [Formula: see text]). We did not observe significant effects on foraging behaviour measured in the subsequent 2 h to 4 h, although the effect size estimate was large (0.29). We also analyzed tissues collected 24 h after the final dose and did not observe significant effects on immune response or cholinesterase activity, although this may be related to our small sample size. We determined that hummingbirds excrete imidacloprid quickly (elimination half-life of [Formula: see text]) relative to other bird species. Hummingbirds have high energetic demands and store relatively little energy, especially during migration and breeding seasons. Therefore, changes in their metabolism following exposures to imidacloprid observed herein could bear important survivorship consequences for hummingbirds.
- Published
- 2021
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28. Determination of neonicotinoids and butenolide residues in avian and insect pollinators and their ambient environment in Western Canada (2017, 2018).
- Author
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Bishop CA, Woundneh MB, Maisonneuve F, Common J, Elliott JE, and Moran AJ
- Subjects
- 4-Butyrolactone analogs & derivatives, Animals, Bees, British Columbia, Insecta, Neonicotinoids, Saskatchewan, Insecticides analysis, Nitro Compounds
- Abstract
To examine the spatial, and temporal variation and potential sources of pesticide concentrations, primarily neonicotinoid insecticides, in hummingbirds in western Canada, we sampled their cloacal fluid from sites in British Columbia and Saskatchewan, Canada in 2017-2018. At a sub-sample of those sites, we also measured pesticides in honey bee (Apis mellifera) nectar, water, and sediment. We collected cloacal fluid from 5 species of hummingbirds (n = 26 sites) in British Columbia (BC) and Saskatchewan, Canada, and nectar from honey bee hives (n = 4 sites), water and sediment (n = 18 sites) in the Fraser Valley, BC. Among those, multiple types of samples were collected at 6 sites. We report the first measurement of flupyradifurone, a relatively new butenolide insecticide, in wildlife which was detected at 4.58 ng/mL in hummingbird cloacal fluid and 2.18 ng/g in honey bee nectar. We also detected three other neonicotinoids (imidacloprid, clothianidin, acetamiprid) and one metabolite desnitro-imidacloprid, and MGK264, a pesticide synergist, in our samples. Among 49 samples of cloacal fluid from rufous (Selasphorus rufus), Anna's (Calypte anna), calliope (Selasphorus calliope) black-chinned (Archilocus alexandri) and ruby-throated hummingbirds (Archilocus colubris), 26.5% (n = 13) contained neonicotinoids. Maximum pesticide concentrations in hummingbirds, water and sediment were found in samples collected in the Fraser Valley, BC within 0.5 km of conventionally sprayed blueberry fields (CSBF) but highest levels in honey bee nectar were detected at a site 1.5 km from a CSBF. Imidacloprid in honey bee nectar at one site exceeded concentrations (>1 ng/g) that can sublethally affect worker bee foraging efficiency. In water, imidacloprid concentrations at another site exceeded Canadian guidelines (230 ng/mL) for the protection of aquatic invertebrates., Competing Interests: Declaration of competing interest We wish to state that there was no conflict of interest in regards to this manuscript., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2020
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29. Wood burning: A major source of Volatile Organic Compounds during wintertime in the Paris region.
- Author
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Languille B, Gros V, Petit JE, Honoré C, Baudic A, Perrussel O, Foret G, Michoud V, Truong F, Bonnaire N, Sarda-Estève R, Delmotte M, Feron A, Maisonneuve F, Gaimoz C, Formenti P, Kotthaus S, Haeffelin M, and Favez O
- Abstract
Wood burning is widely used for domestic heating and has been identified as a ubiquitous pollution source in urban areas, especially during cold months. The present study is based on a three and a half winter months field campaign in the Paris region measuring Volatile Organic Compounds (VOCs) by Proton Transfer Reaction Mass Spectrometry (PTR-MS) in addition to Black Carbon (BC). Several VOCs were identified as strongly wood burning-influenced (e.g., acetic acid, furfural), or traffic-influenced (e.g., toluene, C8-aromatics). Methylbutenone, benzenediol and butandione were identified for the first time as wood burning-related in ambient air. A Positive Matrix Factorization (PMF) analysis highlighted that wood burning is the most important source of VOCs during the winter season. (47%). Traffic was found to account for about 22% of the measured VOCs during the same period, whereas solvent use plus background accounted altogether for the remaining fraction. The comparison with the regional emission inventory showed good consistency for benzene and xylenes but revisions of the inventory should be considered for several VOCs such as acetic acid, C9-aromatics and methanol. Finally, complementary measurements acquired simultaneously at other sites in Île-de-France (the Paris region) enabled evaluation of spatial variabilities. The influence of traffic emissions on investigated pollutants displayed a clear negative gradient from roadside to suburban stations, whereas wood burning pollution was found to be fairly homogeneous over the region., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2020
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30. Lethal and Sublethal Toxicity of Thiamethoxam and Clothianidin Commercial Formulations to Soil Invertebrates in a Natural Soil.
- Author
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Ritchie EE, Maisonneuve F, Scroggins RP, and Princz JI
- Subjects
- Animals, Arthropods drug effects, Arthropods growth & development, Guanidines chemistry, Insecticides chemistry, Insecticides toxicity, Neonicotinoids chemistry, Oligochaeta drug effects, Oligochaeta growth & development, Reproduction drug effects, Soil Pollutants chemistry, Thiamethoxam chemistry, Thiazoles chemistry, Toxicity Tests, Guanidines toxicity, Neonicotinoids toxicity, Soil Pollutants toxicity, Thiamethoxam toxicity, Thiazoles toxicity
- Abstract
The use of neonicotinoids in agriculture is a critical environmental protection issue. Although there has been considerable research on pollinator exposure and aquatic toxicological effects, few studies have investigated the chronic impacts on soil-dwelling species. Given the application of neonicotinoids into soil systems, there is the potential for risk to soil invertebrates. The toxicity of 2 commercial formulations containing the active ingredients (a.i.) thiamethoxam (Actara
® 240SC) or clothianidin (Titan™) was investigated using 3 soil invertebrate species: Oppia nitens, Eisenia andrei, and Folsomia candida. No adverse effects were observed for O. nitens at the highest tested concentrations (≥92 mg a.i./kg dry soil) after a 28-d exposure. Exposure to clothianidin resulted in a 28-d median inhibitory concentration (IC50) of 0.069 (95% confidence limits: 0.039-0.12) mg/kg dry soil for F. candida, and a 56-d IC50 of 0.26 (0.22-3.2) mg a.i./kg dry soil for E. andrei. Exposure to thiamethoxam was less toxic, with IC50s of 0.36 (0.19-0.66) and 3.0 (2.2-4.0) mg a.i./kg dry soil for F. candida and E. andrei reproduction, respectively. The observed toxicity for F. candida adult survival and reproduction and for E. andrei reproduction occurred at environmentally relevant concentrations. However, because clothianidin is a degradation product of thiamethoxam, and detection of clothianidin rose to levels of concern in the thiamethoxam-amended soils over time, the observed toxicity may be partly attributed to the presence of clothianidin. Environ Toxicol Chem 2019;38:2111-2120. © 2019 Crown in the right of Canada. Published by Wiley Periodicals Inc. on behalf of SETAC., (© 2019 Crown in the right of Canada. Published by Wiley Periodicals Inc. on behalf of SETAC.)- Published
- 2019
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31. [Alcoholic disease in women, what specificities?]
- Author
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Bouvet de la Maisonneuve F and Laqueille X
- Subjects
- Alcoholism epidemiology, Female, Humans, Referral and Consultation, Women's Health
- Abstract
Alcoholic disease in women, what specificities? Alcoholic disease in women has long been neglected. Taboo, culturally, it has also probably been so in the field of research and on clinical practice. But this has changed since the recent publication of some very relevant studies that attracted particular attention from a part of the public opinion who came in support of professionals alarmed by the inaction on this subject. Based on a specific clinical experience and from epidemiological studies, clinical data and the complications due to alcohol misuse by women, this article demonstrates the need to focus more on this pathology as it is serious for the patients as well as for their entourage. Indeed, complications seem to be able to develop from the first drink: they are somatic, psychiatric, but also social. There are specificities of this disease in women both through the factors of vulnerability but also by the clinical presentation or by its consequences. Women are more vulnerable than men to alcohol. The lack of knowledge from which this disease suffers leads to longer delays before consultation of patients and insidiously installs complications that are heavier than those of men. In fact, care requires a specific approach in relation to a request and a still particular status attributed to women. It is important to increase the information work in order to encourage patients to consult but also to better legislate on the promotion that mainly targets women and young people, and this in the framework of a more rigorous and efficient prevention., Competing Interests: Les auteurs déclarent n’avoir aucun lien d’intérêts.
- Published
- 2019
32. Hummingbirds and bumble bees exposed to neonicotinoid and organophosphate insecticides in the Fraser Valley, British Columbia, Canada.
- Author
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Bishop CA, Moran AJ, Toshack MC, Elle E, Maisonneuve F, and Elliott JE
- Subjects
- Animals, British Columbia, Flowers chemistry, Flowers drug effects, Geography, Limit of Detection, Pollen chemistry, Pollen drug effects, Pollination, Bees physiology, Birds physiology, Environmental Exposure analysis, Insecticides toxicity, Neonicotinoids toxicity, Organophosphorus Compounds toxicity
- Abstract
To measure exposure to neonicotinoid and other pesticides in avian pollinators, we made novel use of cloacal fluid and fecal pellets from rufous (Selasphorus rufus) and Anna's (Calypte anna) hummingbirds living near blueberry fields in the Fraser River Valley and Vancouver Island, British Columbia, Canada. To examine on-farm exposure to pesticides in invertebrate pollinators, we also collected bumble bees native to Canada (Bombus mixtus, Bombus flavifrons, and Bombus melanopygus), their pollen, and blueberry leaves and flowers from within conventionally sprayed and organic blueberry farms. By sites and sample type, the results reported in the present study represent pooled samples (n = 1). In 2015 to 2016, the combined concentration of the neonicotinoid insecticides imidacloprid, thiamethoxam, and clothianidin detected in hummingbird cloacal fluid from sites near conventionally sprayed blueberry fields was 3.63 ng/mL (ppb). Among the 18 compounds measured in fecal pellets, including one neonicotinoid (imidacloprid), only piperonyl butoxide was detected (1.47-5.96 ng/g). Piperonyl butoxide is a cytochrome P450 inhibitor applied with some insecticides to increase their toxic efficacy. Only diazinon was detected in bumble bees (0.197 ng/g), whereas diazinon (1.54-1.7 ng/g) and imidacloprid (up to 18.4 ng/g) were detected in pollen collected from bumble bees including the bees from organic sites located near conventionally sprayed blueberry farms. Imidacloprid was also detected at 5.16 ng/g in blueberry flowers collected 1 yr post spray from 1 of 6 conventionally sprayed blueberry farms. Environ Toxicol Chem 2018;37:2143-2152. © 2018 SETAC., (© 2018 SETAC.)
- Published
- 2018
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33. Sublethal effects on wood frogs chronically exposed to environmentally relevant concentrations of two neonicotinoid insecticides.
- Author
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Robinson SA, Richardson SD, Dalton RL, Maisonneuve F, Trudeau VL, Pauli BD, and Lee-Jenkins SS
- Subjects
- Animals, Dose-Response Relationship, Drug, Environment, Imidazoles analysis, Insecticides analysis, Larva drug effects, Metamorphosis, Biological drug effects, Neonicotinoids, Nitro Compounds analysis, Oxazines analysis, Ranidae, Thiamethoxam, Thiazoles analysis, Water Pollutants, Chemical analysis, Environmental Monitoring methods, Imidazoles toxicity, Insecticides toxicity, Nitro Compounds toxicity, Oxazines toxicity, Thiazoles toxicity, Water Pollutants, Chemical toxicity
- Abstract
Neonicotinoids are prophylactically used globally on a variety of crops, and there is concern for the potential impacts of neonicotinoids on aquatic ecosystems. The intensive use of pesticides on crops has been identified as a contributor to population declines of amphibians, but currently little is known regarding the sublethal effects of chronic neonicotinoid exposure on amphibians. The objective of the present study was to characterize the sublethal effect(s) of exposure to 3 environmentally relevant concentrations (1 μg/L, 10 μg/L, and 100 μg/L) of 2 neonicotinoids on larval wood frogs (Lithobates sylvaticus) using outdoor mesocosms. We exposed tadpoles to solutions of 2 commercial formulations containing imidacloprid and thiamethoxam, and assessed survival, growth, and development. Exposure to imidacloprid at 10 μg/L and 100 μg/L increased survival and delayed completion of metamorphosis compared with controls. Exposure to thiamethoxam did not influence amphibian responses. There was no significant effect of any treatment on body mass or size of the metamorphs. The results suggest that current usage of imidacloprid and thiamethoxam does not pose a threat to wood frogs. However, further assessment of both direct and indirect effects on subtle sublethal endpoints, and the influence of multiple interacting stressors at various life stages, is needed to fully understand the effects of neonicotinoids on amphibians. Environ Toxicol Chem 2017;36:1101-1109. © 2017 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC., (© 2017 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.)
- Published
- 2017
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34. An assessment of exposure and effects of persistent organic pollutants in an urban Cooper's hawk (Accipiter cooperii) population.
- Author
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Brogan JM, Green DJ, Maisonneuve F, and Elliott JE
- Subjects
- Animals, British Columbia, Environmental Exposure statistics & numerical data, Environmental Pollutants toxicity, Halogenated Diphenyl Ethers blood, Halogenated Diphenyl Ethers toxicity, Polychlorinated Biphenyls blood, Polychlorinated Biphenyls toxicity, Thyroid Hormones blood, Thyroxine blood, Triiodothyronine blood, Environmental Exposure analysis, Environmental Pollutants blood, Hawks physiology
- Abstract
Among the stressors confronting urban wildlife, chemical contaminants pose a particular problem for high trophic feeding species. Previous data from fortuitous carcass collections revealed surprisingly high levels of persistent organic pollutants in raptor species, including the Cooper's hawk (Accipiter cooperii), from urbanized areas of southwestern British Columbia, Canada. Thus, in 2012 and 2013, we followed up on that finding by measuring POPs in blood samples from 21 adult and 15 nestling Cooper's hawks in Vancouver, a large urban area in southwestern Canada. Reproductive success and circulating thyroid hormones were measured to assess possible toxicological effects. Model comparisons showed concentrations of polychlorinated biphenyls (ΣPCBs) were positively influenced by the level of urbanization. Total thyroxin (TT4) was negatively associated with increases in ΣPCBs. Total triiodothyronine (TT3) was negatively associated with ΣPCBs and polybrominated diphenyl ethers (ΣPBDEs). The legacy insecticide, dieldrin, appeared to have some negative influence on reproductive success. There is some evidence of biochemical perturbation by PBDEs and lingering impact of legacy POPs which have not been used for at least 40 years, but overall Cooper's hawks have successfully populated this urban environment.
- Published
- 2017
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35. Sensitivity of the early-life stages of freshwater mollusks to neonicotinoid and butenolide insecticides.
- Author
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Prosser RS, de Solla SR, Holman EAM, Osborne R, Robinson SA, Bartlett AJ, Maisonneuve FJ, and Gillis PL
- Subjects
- 4-Butyrolactone chemistry, 4-Butyrolactone toxicity, Animals, Guanidines chemistry, Guanidines toxicity, Imidazoles chemistry, Imidazoles toxicity, Insecticides chemistry, Neonicotinoids, Nitro Compounds chemistry, Nitro Compounds toxicity, Oxazines chemistry, Oxazines toxicity, Pyridines chemistry, Thiamethoxam, Thiazines chemistry, Thiazines toxicity, Thiazoles chemistry, Thiazoles toxicity, Unionidae growth & development, Water Pollutants, Chemical chemistry, 4-Butyrolactone analogs & derivatives, Environmental Monitoring methods, Fresh Water chemistry, Insecticides toxicity, Pyridines toxicity, Unionidae drug effects, Water Pollutants, Chemical toxicity
- Abstract
Neonicotinoid insecticides can be transported from agricultural fields, where they are used as foliar sprays or seed treatments, to surface waters by surface or sub-surface runoff. Few studies have investigated the toxicity of neonicotinoid or the related butenolide insecticides to freshwater mollusk species. The current study examined the effect of neonicotinoid and butenolide exposures to the early-life stages of the ramshorn snail, Planorbella pilsbryi, and the wavy-rayed lampmussel, Lampsilis fasciola. Juvenile P. pilsbryi were exposed to imidacloprid, clothianidin, or thiamethoxam for 7 or 28 d and mortality, growth, and biomass production were measured. The viability of larval (glochidia) L. fasciola was monitored during a 48 h exposure to six neonicotinoids (imidacloprid, thiamethoxam, clothianidin, acetamiprid, thiacloprid, or dinotefuran), or a butenolide (flupyradifurone). The 7-d LC50s of P. pilsbryi for imidacloprid, clothianidin, and thiamethoxam were ≥4000 μg/L and the 28-d LC50s were ≥182 μg/L. Growth and biomass production were considerably more sensitive endpoints than mortality with EC50s ranging from 33.2 to 122.0 μg/L. The 48-h LC50s for the viability of glochidia were ≥456 μg/L for all seven insecticides tested. Our data indicate that neonicotinoid and butenolide insecticides pose less of a hazard with respect to mortality of the two species of mollusk compared to the potential hazard to other non-target aquatic insects., (Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2016
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36. Increased rodenticide exposure rate and risk of toxicosis in barn owls (Tyto alba) from southwestern Canada and linkage with demographic but not genetic factors.
- Author
-
Huang AC, Elliott JE, Hindmarch S, Lee SL, Maisonneuve F, Bowes V, Cheng KM, and Martin K
- Subjects
- Animals, British Columbia, Dose-Response Relationship, Drug, Environmental Pollutants toxicity, Risk, Anticoagulants toxicity, Environmental Monitoring, Rodenticides toxicity, Strigiformes physiology
- Abstract
Among many anthropogenic drivers of population decline, continual rapid urbanization and industrialization pose major challenges for the survival of wildlife species. Barn owls (Tyto alba) in southwestern British Columbia (BC) face a multitude of threats ranging from habitat fragmentation to vehicle strikes. They are also at risk from secondary poisoning of second-generation anticoagulant rodenticides (SGARs), a suite of toxic compounds which at high doses results in a depletion of blood clotting factors leading to internal bleeding and death. Here, using long-term data (N = 119) for the hepatic residue levels of SGAR, we assessed the risk of toxicosis from SGAR for the BC barn owl population over the past two decades. We also investigated whether sensitivity to SGAR is associated with genetic factors, namely Single Nucleotide Polymorphisms (SNPs) found in the CYP2C45 gene of barn owls. We found that residue concentration for total SGAR was significantly higher in 2006-2013 (141 ng/g) relative to 1992-2003 (57 ng/g). The proportion of owls exposed to multiple SGAR types was also significantly higher in 2006-2013. Those measures accordingly translate directly into an increase in toxicosis risk level. We also detected demographic differences, where adult females showed on average lower concentration of total SGAR (64 ng/g) when compared to adult males (106 ng/g). Juveniles were overall more likely to show signs of toxicosis than adults (33.3 and 6.9 %, respectively), and those symptoms were positively predicted by SGAR concentrations. We found no evidence that SNPs in the CYP2C45 gene of barn owls were associated with intraspecific variation in SGAR sensitivity. We recommend several preventative measures be taken to minimize wildlife exposure to SGAR.
- Published
- 2016
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37. Assessment of toxicity and coagulopathy of brodifacoum in Japanese quail and testing in wild owls.
- Author
-
Webster KH, Harr KE, Bennett DC, Williams TD, Cheng KM, Maisonneuve F, and Elliott JE
- Subjects
- 4-Hydroxycoumarins administration & dosage, Animals, Anticoagulants administration & dosage, Blood Coagulation drug effects, Coturnix metabolism, Dose-Response Relationship, Drug, Hemorrhage epidemiology, Liver metabolism, Prothrombin Time, Rodenticides administration & dosage, Strigiformes metabolism, Time Factors, 4-Hydroxycoumarins toxicity, Anticoagulants toxicity, Hemorrhage chemically induced, Rodenticides toxicity
- Abstract
Based on detection of hepatic residues, scavenging and predatory non-target raptors are widely exposed to second generation anticoagulant rodenticides (SGARs). A small proportion, generally <10%, of tested birds are diagnosed as acutely poisoned. Little is known, however, of sub-lethal effects of SGARs, such as interaction of clotting capacity with traumatic injury. Assessment of coagulation function of birds submitted live to wildlife rehabilitators or veterinarians may provide a means of establishing the proportion of animals suffering sub-lethal coagulopathies, as well as identifying individuals requiring treatment. As a first step in exploring the potential of this approach, we dosed Japanese quail (Coturnix japonica) with the SGAR, brodifacoum, at 0, 0.8, 1.4, 1.9, and 2.5 mg/kg and sampled birds at 1, 3, 5 and 7 days post-dosing. Prothrombin time (PT), which measures the extrinsic coagulation pathway, was significantly prolonged in 98% of brodifacoum-exposed quail in a dose- and time-dependent manner. 50-fold prolongation of PT occurred at higher brodifacoum dosages and correlated to hemorrhage found at necropsy. Activated clotting time (ACT), a measure of the intrinsic pathway also increased with dose and time. Hemoglobin (Hb) and hematocrit (Hct) decreased dose- and time-dependently at doses ≥1.4 mg/kg with no significant change at 0.8 mg/kg. Reference intervals for PT (10.0-16.2 s), ACT (30-180 s), Hb (9.6-18.4 g/dl), and Hct (34-55%) were established in Japanese quail. Species-specific reference intervals are required as barn owl PT (17-29 s) and quail PT were different. The proportion of brodifacoum-exposed quail with hemorrhage was not correlated with liver residues, but was correlated with PT, suggesting that this assay is a useful indicator of avian anticoagulant rodenticide exposure. PTs measured in free-living barn owls sampled between April 2009 and August 2010 in the lower Fraser Valley of BC do not suggest significant exposure to SGARs.
- Published
- 2015
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38. Exposure pathways of anticoagulant rodenticides to nontarget wildlife.
- Author
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Elliott JE, Hindmarch S, Albert CA, Emery J, Mineau P, and Maisonneuve F
- Subjects
- Animals, Anticoagulants analysis, Environmental Exposure statistics & numerical data, Environmental Monitoring, Rodenticides analysis, Anticoagulants metabolism, Birds metabolism, Environmental Exposure analysis, Mammals metabolism, Rodenticides metabolism
- Abstract
Second-generation anticoagulant rodenticides are widely reported to contaminate and poison nontarget wildlife, primarily predatory birds and mammals. Exposure pathways, however, have not been well defined. Here, we examined potential movement of rodenticides from deployment of bait to exposure of small mammals and other biota. At two adjacent working farms, we placed baits containing either brodifacoum or bromadiolone. We monitored movement of those compounds to the surrounding environment by collecting small mammals, birds, and invertebrates. Similar collections were made at a third agricultural setting without active bait deployment, but located among intensive livestock production and regular rodenticide use by farmers. Livers and whole invertebrate samples were analyzed for rodenticides using a sensitive LC-MSMS method. Norway rats (Rattus norvegicus) from both baited and non-baited farms had residues of brodifacoum or bromadiolone, implicating rats as an important exposure pathway to wildlife. Among 35 analyzed nontarget small mammals, a single vole had high hepatic residues (18.6 μ/g), providing some indication of a small mammal pathway. One song sparrow (Melospiza melodia) sample from a baited farm contained 0.073 μg/g of brodifacoum in liver, while 0.39 μg/g of diphacinone was measured in a pool of carrion beetles (Dermestes spp.) from the non-baited farm area, implicating avian and invertebrate components in exposure pathways. Regurgitated pellets of barn owl (Tyto alba) selected randomly from baited farms contained no detectable rodenticide residues, while 90% of owl pellets collected from a variety of farms, and selected for the presence of rat fur, contained detectable anticoagulant residues. We recorded behavior of a captive sample of a representative songbird, the house sparrow (Passer domesticus); they readily entered bait stations and fed on (unloaded) bait.
- Published
- 2014
- Full Text
- View/download PDF
39. Comparative hepatic activity of xenobiotic-metabolizing enzymes and concentrations of organohalogens and their hydroxylated analogues in captive Greenland sledge dogs (Canis familiaris).
- Author
-
Verreault J, Maisonneuve F, Dietz R, Sonne C, and Letcher RJ
- Subjects
- Animals, Cytochrome P-450 CYP1A1 metabolism, Dogs, Epoxide Hydrolases metabolism, Female, Glucuronosyltransferase metabolism, Greenland, Hydroxylation, Mixed Function Oxygenases metabolism, Halogens metabolism, Microsomes, Liver enzymology, Organic Chemicals metabolism, Xenobiotics metabolism
- Abstract
A captive study was performed with Greenland sledge dogs (Canis familiaris) fed a naturally organohalogen-contaminated diet (Greenland minke whale [Balaenoptera acutorostrata] blubber; exposed group) or a control diet (pork fat; control group). The catalytic activity of major xenobiotic-metabolizing phase I and II hepatic microsomal enzymes was assessed. Relative to control dogs, ethoxyresorufin-O-deethylase (EROD) activity in exposed dogs was twofold higher (p = 0.001). Testosterone hydroxylation yielded 6beta- and 16beta-hydroxy (OH) testosterone and androstenedione, with higher rates of production (23-27%; p < or = 0.03) in the exposed individuals. In the exposed dogs, epoxide hydrolase (EH) activity was 31% higher (p = 0.02) relative to the control dogs, whereas uridine diphosphoglucuronosyl transferase (UDPGT) activity was not different (p = 0.62). When the exposed and control dogs were combined, the summed (sigma) plasma concentrations of OH-polychlorinated biphenyl (PCB) congeners were predicted by plasma sigmaPCB concentrations and EROD activity (p < or = 0.04), whereas testosterone hydroxylase, EH, and UDPGT activities were not significant predictors of these concentrations. Consistent results were found for individual OH-PCB congeners and their theoretical precursor PCBs (e.g., 4-OH-CB-187 and CB-183, and 4-OH-CB-146 and CB-146) and for EROD activity. No association was found between sigmaOH-polybrominated diphenyl ether (PBDE) and sigmaPBDE plasma concentrations, or between potential precursor-metabolite pairs, and the enzyme activities. The present results suggest that liver microsomal EROD activity and plasma PCB concentrations have a greater (e.g., relative to EH activity) predictive power for the occurrence of plasma OH-PCB residues in sledge dogs. These results also suggest that plasma OH-PBDEs likely are not products of cytochrome P450-mediated transformation but, rather, are accumulated via the diet.
- Published
- 2009
- Full Text
- View/download PDF
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