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2. Assessing Receptor Activation in 2D and 3D Cultured Hepatocytes: Responses to a Single Compound and a Complex Mixture.

Author

Jamshed, Laiba, Jamshed, Shanza, Frank, Richard A., Hewitt, L. Mark, Thomas, Philippe J., and Holloway, Alison C.

Subjects
TOXICITY testing, NAPHTHENIC acids, CELL communication, COMPLEX compounds, CROSS-cultural studies, CELL culture
Abstract

Responding to global standards and legislative updates in Canada, including Bill S-5 (2023), toxicity testing is shifting towards more ethical, in vitro methods. Traditional two-dimensional (2D) monolayer cell cultures, limited in replicating the complex in vivo environment, have prompted the development of more relevant three-dimensional (3D) spheroidal hepatocyte cultures. This study introduces the first 3D spheroid model for McA-RH7777 cells, assessing xenobiotic receptor activation, cellular signaling, and toxicity against dexamethasone and naphthenic acid (NA)-fraction components; NAFCs. Our findings reveal that 3D McA-RH7777 spheroids demonstrate enhanced sensitivity and more uniform dose–response patterns in gene expression related to xenobiotic metabolism (AhR and PPAR) for both single compounds and complex mixtures. Specifically, 3D cultures showed significant gene expression changes upon dexamethasone exposure and exhibited varying degrees of sensitivity and resistance to the apoptotic effects induced by NAFCs, in comparison to 2D cultures. The optimization of 3D culture conditions enhances the model's physiological relevance and enables the identification of genomic signatures under varied exposures. This study highlights the potential of 3D spheroid cultures in providing a more accurate representation of the liver's microenvironment and advancing our understanding of cellular mechanisms in toxicity testing. [ABSTRACT FROM AUTHOR]

Published
2024
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5. Mucin expression in gastric- and gastro-oesophageal signet-ring cell cancer: results from a comprehensive literature review and a large cohort study of Caucasian and Asian gastric cancer

Author

Kerckhoffs, K. G. P., Liu, D. H. W., Saragoni, L., van der Post, R. S., Langer, R., Bencivenga, M., Iglesias, M., Gallo, G., Hewitt, L. C., Fazzi, G. E., Vos, A. M., Renaud, F., Yoshikawa, T., Oshima, T., Tomezzoli, A., de Manzoni, G., Arai, T., Kushima, R., Carneiro, F., and Grabsch, H. I.

Published
2020
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10. Midwifery group practice workforce in Australia: A cross-sectional survey of midwives and managers.

Author

Hewitt, L, Dadich, A, Hartz, DL, Dahlen, HG, Hewitt, L, Dadich, A, Hartz, DL, and Dahlen, HG

Abstract

BACKGROUND: Despite robust evidence on the benefits of midwifery group practice (MGP), there remains difficulties with implementing and sustaining the model. However, contemporary data on the MGP workforce and how each model has been operationalised are limited. This constrains an understanding of the factors that help or hinder implementation and sustainability of MGP. AIM: To describe the characteristics of Australian MGPs and the factors that help or hinder sustainability. METHODS: A national cross-sectional survey was undertaken in Australia between March 2021 and July 2022, inclusive. Quantitative data were analysed using descriptive analysis while qualitative data were analysed using content analysis. FINDINGS: Of 669 survey responses, 579 were midwives and 90 were managers. The mean years of experience for clinical midwives was eight years, and 47.8% (almost twice the national average) completed a Bachelor of Midwifery (BMid). Half (50.2%) the models provided care for women of all risk. Midwives resigned from MGP because of the MGP work conditions (30%) and how the service was managed or supported (12.7%). Managers resigned from MGP because of role changes, conflict with their manager, and limited support. Almost half (42.6%) of MGP managers also managed other areas, leading to heavy workloads, competing demands, and burnout. CONCLUSION: The BMid appears to be a common educational pathway for MGP midwives, and many MGP services are providing care to women with complexities. Flexible practice agreements, organisational support and appropriate workloads are vital for recruitment, retention, and sustainability of MGP.

Published
2023

12. Future water quality monitoring: improving the balance between exposure and toxicity assessments of real-world pollutant mixtures

Author

Altenburger, Rolf, Brack, Werner, Burgess, Robert M., Busch, Wibke, Escher, Beate I., Focks, Andreas, Mark Hewitt, L., Jacobsen, Bo N., de Alda, Miren López, Ait-Aissa, Selim, Backhaus, Thomas, Ginebreda, Antoni, Hilscherová, Klára, Hollender, Juliane, Hollert, Henner, Neale, Peta A., Schulze, Tobias, Schymanski, Emma L., Teodorovic, Ivana, Tindall, Andrew J., de Aragão Umbuzeiro, Gisela, Vrana, Branislav, Zonja, Bozo, and Krauss, Martin

Published
2019
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13. Offshore Decommissioning Horizon Scan: Research Priorities to Support Decision-Making Activities for Oil and Gas Infrastructure

Author

Watson, Sarah, primary, McLean, Dianne, additional, Balcom, Brian, additional, Birchenough, Silvana N.R., additional, Brand, Alison M., additional, Camprasse, Elodie C.M., additional, Claisse, Jeremy T., additional, Joop, Coolen J.W., additional, Cresswell, Tom, additional, Fokkema, Bert, additional, Susan, Gourvenec, additional, Lea-Anne, Henry, additional, Chad, Hewitt L., additional, Love, Milton S., additional, MacIntosh, Amy, additional, Marnane, Michael, additional, McKinley, Emma, additional, Micallef, Shannon, additional, Morgan, Deborah, additional, Nicolette, Joseph, additional, Ounanian, Kristen, additional, Paterson, John, additional, Seath, Karen, additional, Selman, Allison G.L., additional, Suthers, Iain M., additional, Todd, Victoria L.G., additional, Tung, Aaron, additional, and Macreadie, Peter I., additional

Published
2023
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17. Naphthenic Acid Fraction Compounds Reduce the Reproductive Success of Wood Frogs (Rana Sylvatica) By Affecting Offspring Viability

Author

Robinson, Chloe, Elvidge, Chris, Frank, Richard A., Headley, John V., Hewitt, L. Mark, Little, Alexander, Robinson, Stacey A, Trudeau, Vance, Vander Meulen, Ian, and Orihel, Diane

Subjects
Male, Ranidae, Health, Toxicology and Mutagenesis, Reproduction, Carboxylic Acids, Water, General Medicine, Amphibian, Development, Toxicology, Pollution, Mesocosms, Humans, Animals, Female, Oil and Gas Fields, Naphthenic acids, Water Pollutants, Chemical
Abstract

Understanding the toxicity of organic compounds in oil sands process-affected water (OSPW) is necessary to inform the development of environmental guidelines related to wastewater management in Canada's oil sands region. In the present study, we investigated the effects of naphthenic acid fraction compounds (NAFCs), one of the most toxic components of OSPW, on mating behaviour, fertility, and offspring viability in the wood frog (Rana sylvatica). Wild adult wood frogs were exposed separately from the opposite sex to 0, 5, or 10 mg/L of OSPW-derived NAFCs for 24 h and then combined in outdoor lake water mesocosms containing the same NAFC concentrations (n = 2 males and 1 female per mesocosm, n = 3 mesocosms per treatment). Mating events were recorded for 48 h and egg masses were measured to determine adult fertility. NAFC exposure had no significant effect on mating behaviour (probability of amplexus and oviposition, amplexus and oviposition latency, total duration of amplexus and number of amplectic events) or fertility (fertilization success and clutch size). Tadpoles (50 individuals per mesocosm at hatching, and 15 individuals per mesocosm from 42 d post-hatch) were reared in the same mesocosms under chronic NAFC exposure until metamorphic climax (61-85 d after hatching). Offspring exposed to 10 mg/L NAFCs during development were less likely to survive and complete metamorphosis, grew at a reduced rate, and displayed more frequent morphological abnormalities. These abnormalities included limb anomalies at metamorphosis, described for the first time after NAFC exposure. The results of this study suggest that NAFCs reduce wood frog reproductive success through declines in offspring viability and therefore raise the concern that exposure to NAFCs during reproduction and development may affect the recruitment of native amphibian populations in the oil sands region.

Published
2022

18. The acute toxicity of bitumen-influenced groundwaters from the oil sands region to aquatic organisms

Author

Bauer, Anthony E., primary, Hewitt, L. Mark, additional, Roy, James W., additional, Parrott, Joanne L., additional, Bartlett, Adrienne J., additional, Gillis, Patricia L., additional, Norwood, Warren P., additional, Rudy, Martina D., additional, Campbell, Sheena D., additional, Rodrigues, Maegan R., additional, Brown, Lisa R., additional, Vanderveen, Ruth, additional, Deeth, Lorna E., additional, Holman, Emily A.M., additional, Salerno, Joseph, additional, Marentette, Julie R., additional, Lavalle, Christine, additional, Sullivan, Cheryl, additional, Shires, Kallie, additional, Galicia, Melissa, additional, Rubino, Julian, additional, Brown, Mitra, additional, O'Neill, Alicia, additional, Bickerton, Greg, additional, Dixon, D. George, additional, and Frank, Richard A., additional

Published
2022
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23. Midwife-centred management: a qualitative study of midwifery group practice management and leadership in Australia.

Author

Hewitt, L, Dadich, A, Hartz, DL, Dahlen, HG, Hewitt, L, Dadich, A, Hartz, DL, and Dahlen, HG

Abstract

BACKGROUND: Midwifery group practice (MGP) has consistently demonstrated optimal health and wellbeing outcomes for childbearing women and their babies. In this model, women can form a relationship with a known midwife, improving both maternal and midwife satisfaction. Yet the model is not widely implemented and sustained, resulting in limited opportunities for women to access it. Little attention has been paid to how MGP is managed and led and how this impacts the sustainability of the model. This study clarifies what constitutes optimal management and leadership and how this influences sustainability. METHODS: This qualitative study forms part of a larger mixed methods study investigating the management of MGP in Australia. The interview findings presented in this study are part of phase one, where the findings informed a national survey. Nine interviews and one focus group were conducted with 23 MGP managers, clinical midwife consultants, and operational/strategic managers who led MGPs. Transcripts of the audio-recordings were analysed using inductive, reflexive, thematic analysis. RESULTS: Three themes were constructed, namely: The manager, the person, describing the ideal personal attributes of the MGP manager; midwifing the midwives, illustrating how the MGP manager supports, manages, and leads the group practice midwives; and gaining acceptance, explaining how the MGP manager can gain acceptance beyond group practice midwives. Participants described the need for MGP managers to display midwife-centred management. This requires the manager to have qualities that mirror what is generally accepted as requirements for good midwifery care namely: core beliefs in feminist values and woman-centred care; trust; inclusiveness; being an advocate; an ability to slow down or take time; an ability to form relationships; and exceptional communication skills. Since emotional labour is a large part of the role, it is also necessary for them to encourage and practice self-care

Published
2022

25. Fathead Minnows Exposed to Organic Compounds from Oil Sands Tailings as Embryos Have Reduced Survival, Impaired Development, and Altered Behaviors That Persist into Larval Stages

Author

Reynolds, Jessie S., primary, Jackson, Brianna L., additional, Madison, Barry N., additional, Elvidge, Chris K., additional, Frank, Richard A., additional, Hasler, Caleb T., additional, Headley, John V., additional, Hewitt, L. Mark, additional, Peru, Kerry M., additional, Yakimowski, Sarah B., additional, and Orihel, Diane M., additional

Published
2022
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27. Plasma proteins elevated in severe asthma despite oral steroid use and unrelated to Type-2 inflammation

Author

Mikus, M.S. Kolmert, J. Andersson, L.I. Östling, J. Knowles, R.G. Gómez, C. Ericsson, M. Thörngren, J.-O. Khoonsari, P.E. Dahlén, B. Kupczyk, M. de Meulder, B. Auffray, C. Bakke, P.S. Beghe, B. Bel, E.H. Caruso, M. Chanez, P. Chawes, B. Fowler, S.J. Gaga, M. Geiser, T. Gjomarkaj, M. Horváth, I. Howarth, P.H. Johnston, S.L. Joos, G. Krug, N. Montuschi, P. Musial, J. Niżankowska-Mogilnicka, E. Olsson, H.K. Papi, A. Rabe, K.F. Sandström, T. Shaw, D.E. Siafakas, N.M. Uhlén, M. Riley, J.H. Bates, S. Middelveld, R.J.M. Wheelock, C.E. Chung, K.F. Adcock, I.M. Sterk, P.J. Djukanovic, R. Nilsson, P. Dahlén, S.-E. James, A. Ahmed, H. Balgoma, D. Bansal, A.T. Baribaud, F. Bigler, J. Billing, B. Bisgaard, H. Boedigheimer, M.J. Bønnelykke, K. Brandsma, J. Brinkman, P. Bucchioni, E. Burg, D. Bush, A. Chaiboonchoe, A. Checa, T. Compton, C.H. Corfield, J. Cunoosamy, D. D’Amico, A. Emma, R. Erpenbeck, V.J. Erzen, D. Fichtner, K. Fitch, N. Fleming, L.J. Formaggio, E. Frey, U. Gahlemann, M. Goss, V. Guo, Y.-K. Hashimoto, S. Haughney, J. Hedlin, G. Hekking, P.-P.W. Higenbottam, T. Hohlfeld, J.M. Holweg, C.T.J. Knox, A.J. Konradsen, J. Lazarinis, N. Lefaudeux, D. Li, T. Loza, M.J. Lutter, R. Manta, A. Masefield, S. Matthews, J.G. Mazein, A. Meiser, A. Miralpeix, M. Mores, N. Murray, C.S. Myles, D. Naz, S. Nordlund, B. Pahus, L. Pandis, I. Pavlidis, S. Postle, A. Powel, P. Rao, N. Reinke, S. Roberts, A. Roberts, G. Rowe, A. Schofield, J.P.R. Seibold, W. Selby, A. Sigmund, R. Singer, F. Sjödin, M. Skipp, P.J. Sousa, A.R. Sun, K. Thornton, B. Uddin, M. van Aalderen, W.M. van Geest, M. Vestbo, J. Vissing, N.H. Wagener, A.H. Wagers, S.S. Weiszhart, Z. Wheelock, C.E. Wheelock, Å. Wilson, S.J. Yasinska, V. Brusselle, G.G. Campbell, D.A. Contoli, M. Damm, K. de Rudder, I. Delin, I. Devautour, C. Duplaga, M. Eduards, M. Ek, A. Ekström, T. Figiel, E. Gaber, F. Gauw, S. Gawlewicz-Mroczka, A. Gerding, D. Haque, S. Hewitt, L. Hiemstra, P.S. Holgate, S.T. Holloway, J. Kania, A. Kanniess, F. Karlsson, Ö. Kips, J.C. Kumlin, M. Lantz, A.-S. Lazarinis, N. Magnussen, H. Mallia, P. Martling, I. Meziane, L. Oikonomidou, E. Olsson, M. Pace, E. Papadopouli, E. Papadopoulos, N. Plataki, M. Profita, M. Reinius, L.E. Richter, K. Robinson, D.S. Romagnoli, M. Samara, K. Schelfhout, V. Skedinger, M. Stamataki, E. ten Brinke, A. Vachier, I. Wallén-Nielsen, E. van Veen, I. Weersink, E. Wilson, S.J. Yasinska, V. Zervas, E. Ziolkowska-Graca, B. U-BIOPRED (Unbiased Biomarkers for the Prediction of Respiratory Disease outcome) Study Group BIOAIR (Longitudinal Assessment of Clinical Course Biomarkers in Severe Chronic Airway Disease) Consortium

Abstract

Rationale Asthma phenotyping requires novel biomarker discovery. Objectives To identify plasma biomarkers associated with asthma phenotypes by application of a new proteomic panel to samples from two well-characterised cohorts of severe (SA) and mild-to-moderate (MMA) asthmatics, COPD subjects and healthy controls (HCs). Methods An antibody-based array targeting 177 proteins predominantly involved in pathways relevant to inflammation, lipid metabolism, signal transduction and extracellular matrix was applied to plasma from 525 asthmatics and HCs in the U-BIOPRED cohort, and 142 subjects with asthma and COPD from the validation cohort BIOAIR. Effects of oral corticosteroids (OCS) were determined by a 2-week, placebo-controlled OCS trial in BIOAIR, and confirmed by relation to objective OCS measures in U-BIOPRED. Results In U-BIOPRED, 110 proteins were significantly different, mostly elevated, in SA compared to MMA and HCs. 10 proteins were elevated in SA versus MMA in both U-BIOPRED and BIOAIR (alpha-1-antichymotrypsin, apolipoprotein-E, complement component 9, complement factor I, macrophage inflammatory protein-3, interleukin-6, sphingomyelin phosphodiesterase 3, TNF receptor superfamily member 11a, transforming growth factor-β and glutathione S-transferase). OCS treatment decreased most proteins, yet differences between SA and MMA remained following correction for OCS use. Consensus clustering of U-BIOPRED protein data yielded six clusters associated with asthma control, quality of life, blood neutrophils, high-sensitivity C-reactive protein and body mass index, but not Type-2 inflammatory biomarkers. The mast cell specific enzyme carboxypeptidase A3 was one major contributor to cluster differentiation. Conclusions The plasma proteomic panel revealed previously unexplored yet potentially useful Type-2independent biomarkers and validated several proteins with established involvement in the pathophysiology of SA. © 2022 European Respiratory Society. All rights reserved.

Published
2022

28. Plasma proteins elevated in severe asthma despite oral steroid use and unrelated to Type-2 inflammation

Author

Mikus, M. S., Kolmert, J., Andersson, L. I., Ostling, J., Knowles, R. G., Gomez, C., Ericsson, M., Thorngren, J. -O., Khoonsari, P. E., Dahlen, B., Kupczyk, M., de Meulder, B., Auffray, C., Bakke, P. S., Beghe, Bianca, Bel, E. H., Caruso, M., Chanez, P., Chawes, B., Fowler, S. J., Gaga, M., Geiser, T., Gjomarkaj, M., Horvath, I., Howarth, P. H., Johnston, S. L., Joos, G., Krug, N., Montuschi, P., Musial, J., Nizankowska-Mogilnicka, E., Olsson, H. K., Papi, A., Rabe, K. F., Sandstrom, T., Shaw, D. E., Siafakas, N. M., Uhlen, M., Riley, J. H., Bates, S., Middelveld, R. J. M., Wheelock, C. E., Chung, K. F., Adcock, I. M., Sterk, P. J., Djukanovic, R., Nilsson, P., Dahlen, S. -E., James, A., Ahmed, H., Balgoma, D., Bansal, A. T., Baribaud, F., Bigler, J., Billing, B., Bisgaard, H., Boedigheimer, M. J., Bonnelykke, K., Brandsma, J., Brinkman, P., Bucchioni, E., Burg, D., Bush, A., Chaiboonchoe, A., Checa, T., Compton, C. H., Corfield, J., Cunoosamy, D., D'Amico, A., Emma, R., Erpenbeck, V. J., Erzen, D., Fichtner, K., Fitch, N., Fleming, L. J., Formaggio, E., Frey, U., Gahlemann, M., Goss, V., Guo, Y. -K., Hashimoto, S., Haughney, J., Hedlin, G., Hekking, P. -P. W., Higenbottam, T., Hohlfeld, J. M., Holweg, C. T. J., Knox, A. J., Konradsen, J., Lazarinis, N., Lefaudeux, D., Li, T., Loza, M. J., Lutter, R., Manta, A., Masefield, S., Matthews, J. G., Mazein, A., Meiser, A., Miralpeix, M., Mores, N., Murray, C. S., Myles, D., Naz, S., Nordlund, B., Pahus, L., Pandis, I., Pavlidis, S., Postle, A., Powel, P., Rao, N., Reinke, S., Roberts, A., Roberts, G., Rowe, A., Schofield, J. P. R., Seibold, W., Selby, A., Sigmund, R., Singer, F., Sjodin, M., Skipp, P. J., Sousa, A. R., Sun, K., Thornton, B., Uddin, M., van Aalderen, W. M., van Geest, M., Vestbo, J., Vissing, N. H., Wagener, A. H., Wagers, S. S., Weiszhart, Z., Wheelock, A., Wilson, S. J., Yasinska, V., Brusselle, G. G., Campbell, D. A., Contoli, M., Damm, K., de Rudder, I., Delin, I., Devautour, C., Duplaga, M., Eduards, M., Ek, A., Ekstrom, T., Figiel, E., Gaber, F., Gauw, S., Gawlewicz-Mroczka, A., Gerding, D., Haque, S., Hewitt, L., Hiemstra, P. S., Holgate, S. T., Holloway, J., Kania, A., Kanniess, F., Karlsson, O., Kips, J. C., Kumlin, M., Lantz, A. -S., Magnussen, H., Mallia, P., Martling, I., Meziane, L., Oikonomidou, E., Olsson, M., Pace, E., Papadopouli, E., Papadopoulos, N., Plataki, M., Profita, M., Reinius, L. E., Richter, K., Robinson, D. S., Romagnoli, M., Samara, K., Schelfhout, V., Skedinger, M., Stamataki, E., ten Brinke, A., Vachier, I., Wallen-Nielsen, E., van Veen, I., Weersink, E., Zervas, E., and Ziolkowska-Graca, B.

Subjects
Blood Proteins, Humans, Inflammation, Proteomics, Severity of Illness Index, Steroids, Asthma, Quality of Life
Published
2022

30. The Acute Toxicity of Bitumen-Influenced Groundwaters from the Oil Sands Region to Aquatic Organisms

Author

Frank, Richard A., primary, Bauer, Anthony E., additional, Hewitt, L. Mark, additional, Roy, James W., additional, Parrott, Joanne L., additional, Bartlett, Adrienne J., additional, Gillis, Patricia L., additional, Norwood, Warren P., additional, Rudy, Martina D., additional, Campbell, Sheena D., additional, Rodrigues, Maegan R., additional, Brown, Lisa R., additional, Vanderveen, Ruth, additional, Deeth, Lorna E., additional, Holman, Emily A. M., additional, Salerno, Joseph, additional, Marentette, Julie R., additional, Lavalle, Christine, additional, Sullivan, Cheryl, additional, Shires, Kallie, additional, Galicia, Melissa, additional, Rubino, Julian, additional, Brown, Mitra, additional, O’Neill, Alicia, additional, Bickerton, Greg, additional, and Dixon, D. George, additional

Published
2022
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34. Polycyclic aromatic compounds in the Canadian Environment: Aquatic and terrestrial environments

Author

Marvin, Christopher H., primary, Berthiaume, Alicia, additional, Burniston, Deborah A., additional, Chibwe, Leah, additional, Dove, Alice, additional, Evans, Marlene, additional, Hewitt, L. Mark, additional, Hodson, Peter V., additional, Muir, Derek C.G., additional, Parrott, Joanne, additional, Thomas, Philippe J., additional, and Tomy, Gregg T., additional

Published
2021
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36. Management and sustainability of midwifery group practice: Thematic and lexical analyses of midwife interviews

Author

Hewitt, L, Dadich, A, Hartz, DL, and Dahlen, HG

Subjects
Obstetrics & Reproductive Medicine, 11 Medical and Health Sciences
Abstract

BackgroundAlthough there is high-level evidence supporting positive perinatal outcomes for midwifery group practice (MGP) care, not all women can access this model due to a failure to implement or sustain it. The way that MGPs are managed could be an important factor in whether they are successful in the long-term.AimTo explore what determines optimal management of MGP in Australia, and the influence it has on sustainability of MGP.MethodsInterviews were conducted with MGP midwives (n=8). Transcriptions of the audio recordings were analysed thematically and lexically for triangulation.FindingsFollowing a thematic analysis of the data, an over-arching theme emerged - namely - being valued and supported, with three sub-themes: a nice little sweet spot, someone to stand up for you, and building relationships and support beyond the model. This revealed that value and support by all stakeholders, including the midwives themselves, was necessary to sustain an MGP. The lexical analysis revealed the themes: support, the system, and the caseload. This analysis highlighted the importance of the system - specifically, the impact of the institution on how MGP is operationalised.ConclusionFor MGP to be sustained in Australia, it needs to be prioritised, nurtured, and embraced by the whole maternity care system. Management plays an important role in ensuring the right people are employed to pivotal positions and that midwifery-led models of care are valued and supported throughout the system.

Published
2021

40. Preparative isolation, fractionation and chemical characterization of dissolved organics from natural and industrially derived bitumen-influenced groundwaters from the Athabasca River watershed

Author

Frank, Richard A., primary, Bauer, Anthony E., additional, Roy, James W., additional, Bickerton, Greg, additional, Rudy, Martina D., additional, Vanderveen, Ruth, additional, Batchelor, Suzanne, additional, Barrett, Sophie E., additional, Milestone, Craig B., additional, Peru, Kerry M., additional, Headley, John V., additional, Brunswick, Pamela, additional, Shang, Dayue, additional, Farwell, Andrea J., additional, Dixon, D. George, additional, and Hewitt, L. Mark, additional

Published
2021
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42. Non-target profiling of bitumen-influenced waters for the identification of tracers unique to oil sands processed-affected water (OSPW) in the Athabasca watershed of Alberta, Canada

Author

Milestone, Craig B., Sun, Chenxing, Martin, Jonathan W., Bickerton, Greg, Roy, James W., Frank, Richard A., Hewitt, L. Mark, Milestone, Craig B., Sun, Chenxing, Martin, Jonathan W., Bickerton, Greg, Roy, James W., Frank, Richard A., and Hewitt, L. Mark

Abstract

Rationale The objective of this study was to identify unique chemical tracers of oil sands process-affected water (OSPW) to enable definitive discrimination of tailings pond seepage from natural bitumen-influenced waters from the Canadian Alberta McMurray formation. Methods The approach involved comparing unknowns from an unprecedented sample set of OSPW (n = 4) and OSPW-affected groundwaters (n = 15) with natural bitumen-influenced groundwaters (n = 20), using high-performance liquid chromatography/electrospray ionisation high-resolution mass spectrometry (HPLC/ESI-HRMS) operated in both polarities. Results Four unknown chemical entities were identified as potential tracers of OSPW seepage and subsequently subjected to structural elucidation. One potential tracer, tentatively identified as a thiophene-containing carboxylic acid [C15H23O3S](-), was only detected in OSPW and OSPW-affected samples, thereby showing the greatest diagnostic potential. The remaining three unknowns, postulated to be two thiochroman isomers [C17H25O3S](+) and an ethyl-naphthalene isomer [C16H21](+), were detected in one and two background groundwaters, respectively. Conclusions We advanced the state of knowledge for tracers of tailings seepage beyond heteroatomic classes, to identifying diagnostic substances, with structures postulated. Synthesis of the four proposed structures is recommended to enable structural confirmations. This research will guide and inform the Oil Sands Monitoring Program in its efforts to assess potential influences of oil sands development on the Athabasca River watershed.

Published
2021
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