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. (2021). A Bad Start in Life? Maternal Transfer of Legacy and Emerging Poly- and Perfluoroalkyl Substances to Eggs in an Arctic Seabird (Vol. 56).
Abstract: In birds, maternal transfer is a major exposure route for several contaminants, including poly- and perfluoroalkyl substances (PFAS). Little is known, however, about the extent of the transfer of the different PFAS compounds to the eggs, especially for alternative fluorinated compounds. In the present study, we measured legacy and emerging PFAS, including Gen-X, ADONA, and F-53B, in the plasma of prelaying black-legged kittiwake females breeding in Svalbard and the yolk of their eggs. We aimed to (1) describe the contaminant levels and patterns in both females and eggs, and (2) investigate the maternal transfer, that is, biological variables and the relationship between the females and their eggs for each compound. Contamination of both females and eggs were dominated by linPFOS then PFUnA or PFTriA. We notably found 7:3 fluorotelomer carboxylic acid?a precursor of long-chain carboxylates?in 84% of the egg yolks, and provide the first documented finding of ADONA in wildlife. Emerging compounds were all below the detection limit in female plasma. There was a linear association between females and eggs for most of the PFAS. Analyses of maternal transfer ratios in females and eggs suggest that the transfer is increasing with PFAS carbon chain length, therefore the longest chain perfluoroalkyl carboxylic acids (PFCAs) were preferentially transferred to the eggs. The mean ?PFAS in the second-laid eggs was 73% of that in the first-laid eggs. Additional effort on assessing the outcome of maternal transfers on avian development physiology is essential, especially for PFCAs and emerging fluorinated compounds which are under-represented in experimental studies.
Programme: 330
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William J. Pringle, Damrongsak Wirasaet, Andika Suhardjo, Jessica Meixner, Joannes J. Westerink, Andrew B. Kennedy, Shangyao Nong. (2018). Finite-Element barotropic model for the Indian and Western Pacific Oceans: Tidal model-data comparisons and sensitivities (Vol. 129).
Abstract: In this study, a 9.6 million node large-scale unstructured grid finite-element forward barotropic model is developed and applied to understand the tidal dynamics and dissipation mechanisms of the Indian and western Pacific Oceans down to sub-kilometer scale at the coast. Tidal model-data comparisons are presented to assess the capabilities and limitations of our large-scale barotropic model. The average root-mean-square (RMS) discrepancies of tidal elevations at coastal tide gauges is 14 cm, which is ???3 cm smaller than those of a state-of-the-art global data assimilated barotropic tidal model. Sensitivities to lateral boundary conditions, bathymetry, and dissipative processes are explored to guide future endeavors related to large-scale barotropic modeling in the region and other regions throughout the world. Lateral boundary conditions are found to induce adverse resonant effects on the lunar semi-diurnal modes when poorly placed elevation specified boundary conditions are used. This problem is largely resolved by using an absorption-generation layer at the boundary. Parameterization of internal tide energy conversion is identified as the most important aspect to control deep water solutions, and help reduce the RMS discrepancies of the entire system. Two forms of this parameterization are presented and their spatial distributions of dissipation are compared. Bathymetry has a negligible effect on the tidal solutions in deep water, but local high resolution bathymetry results in significant reductions to the average RMS discrepancies on the continental shelf (26%) and at the coast (30%). Implementing a spatially varying bottom friction coefficient based on sediment types decreases the average RMS discrepancy at the coast by 9% predominantly due to its positive effects in the Yellow Sea. The model is shown to capture a large amount of the tidal physics and has the potential for application to a range of barotropic problems such as wind-driven surge and tidal processes.
Keywords: Barotropic tides Bathymetry Bottom friction Finite-element Internal tide energy conversion Unstructured grid
Programme: 688
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. (2022). Metabolic heat loss in southern elephant seals (Mirounga leonina) differs with stage of moult and between habitats (Vol. 104).
Keywords: Heat loss Marine mammals Moult Pinnipeds Skin temperature Thermoregulation
Programme: 1201
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Willener, A.S.T., Halsey, L.G., & Y. Handrich, . (2012). Are king penguins stressed during respirometry experiments? A potential confound for energetics calibration studies. Society for Experimental Biology Annual Main Meeting. 29th June – 2nd July 2012. Salzburg, Austria..
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Willener, A., Handrich, Y. Abourachid, A. & L.G. Halsey
. (2010).
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Willener, A., Abourachid, A., Halsey L.G. & Y. Handrich. (2010).
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. (2015). Reassessment of the cardio-respiratory stress response, using the king penguin as a model
. Stress, 18(1), 115–120.
Abstract: AbstractResearch in to short-term cardio-respiratory changes in animals in reaction to a psychological stressor typically describes increases in rate of oxygen consumption and heart rate. Consequently, the broad consensus is that they represent a fundamental stressor response generalizable across adult species. However, movement levels can also change in the presence of a stressor, yet studies have not accounted for this possible confound on heart rate. Thus the direct effects of psychological stressors on the cardio-respiratory system are not resolved. We used an innovative experimental design employing accelerometers attached to king penguins (Aptenodytes patagonicus) to measure and thus account for movement levels in a sedentary yet free-to-move animal model during a repeated measures stress experiment. As with previous studies on other species, incubating king penguins (N?=?6) exhibited significant increases in both and heart rate when exposed to the stressor. However, movement levels, while still low, also increased in response to the stressor. Once this was accounted for by comparing periods of time during the control and stress conditions when movement levels were similar as recorded by the accelerometers, only significantly increased; there was no change in heart rate. These findings offer evidence that changing movement levels have an important effect on the measured stress response and that the cardio-respiratory response per se to a psychological stressor (i.e. the response as a result of physiological changes directly attributable to the stressor) is an increase in without an increase in heart rate.
Programme: 394
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Willener A.S.T., Handrich Y., Strike S., Abourachid A., & L. Halsey . (2010). The energetics of pedestrian locomotion in king penguin Aptenodytes patagonica. 25th International Ornithological Congress, 22nd – 28th of August, 2010, Campos do Jordao, Brazil..
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Willener A.S.T., Handrich Y., Strike S., Abourachid A., & L. Halsey
. (2010). The energetics of pedestrian locomotion in king penguin Aptenodytes patagonica..
Abstract: Conference of the Society for Experimental Biology, 30th June – 3rd July, 2010, Prague, Czech Republic.
Programme: 394
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Willener A., Handrich Y., Strike S., Abourachid A. & L. Halsey . (2011). Can biomechanics uncover the paradox of the efficient fat penguin ? Conference of the Society of Experimental Biology. 1st-4st of July, 2011. Glasgow , United Kingdom. Won the second General Biomechanics Poster Prize.
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