Publications by authors named "Stephen Nicol"

Antarctic krill (Euphausia superba) are a key component of the Antarctic food web with considerable lipid reserves that are vital for their health and higher predator survival. Krill lipids are primarily derived from their diet of plankton, in particular diatoms and flagellates. Few attempts have been made to link the spatial and temporal variations in krill lipids to those in their food supply.

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Euphausia superba (Antarctic krill) is a keystone species in the Southern Ocean, but little is known about how it will respond to climate change. Ocean acidification, caused by sequestration of carbon dioxide into ocean surface waters (pCO), alters the lipid biochemistry of some organisms. This can have cascading effects up the food chain.

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Article Synopsis
  • - Antarctic krill are crucial for the Southern Ocean ecosystem as they serve as the main food source for various predators, making their population stability vital for ecological health.
  • - Climate change, particularly through increased CO2 emissions, leads to ocean acidification, which poses risks to many marine species but has unclear effects on krill.
  • - Laboratory tests reveal that adult krill can survive and thrive (growing, maturing, and maintaining metabolic functions) under conditions simulating near-future ocean acidification, showcasing their ability to regulate internal acid-base balance and suggesting resilience to changing ocean conditions.
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Aims: Fragility femoral fractures occur in a similar group of patients to hip fractures but they are not routinely managed along standardised guidelines. This study looked specifically at whether delay to surgery has an impact on mortality and morbidity.

Patients And Methods: An international, multi-centre retrospective review was carried including all patients over 60 years with fragility femoral fractures, including most periprosthetic fractures, between December 2008-2014.

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The availability of micronutrients is a key factor that affects primary productivity in High Nutrient Low Chlorophyll (HNLC) regions of the Southern Ocean. Nutrient supply is governed by a range of physical, chemical and biological processes, and there are significant feedbacks within the ecosystem. It has been suggested that baleen whales form a crucial part of biogeochemical cycling processes through the consumption of nutrient-rich krill and subsequent defecation, but data on their contribution are scarce.

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Antarctic and Southern Ocean (ASO) marine ecosystems have been changing for at least the last 30 years, including in response to increasing ocean temperatures and changes in the extent and seasonality of sea ice; the magnitude and direction of these changes differ between regions around Antarctica that could see populations of the same species changing differently in different regions. This article reviews current and expected changes in ASO physical habitats in response to climate change. It then reviews how these changes may impact the autecology of marine biota of this polar region: microbes, zooplankton, salps, Antarctic krill, fish, cephalopods, marine mammals, seabirds, and benthos.

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The role of total hip arthroplasty (THA) for fracture in octogenarians remains unclear. Over a two-year period, 354 patients aged > 80 years were admitted with a displaced intracapsular hip fracture. Using defined clinical guidelines, 38 patients underwent THA with a median age of 84 years, mean follow-up of 20 months.

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Acute compartment syndrome (ACS) of the thigh is an uncommon condition usually treated surgically by emergency dermofasciotomy. We report a rare case of acute delayed compartment syndrome of the anterior compartment of the thigh following an uncemented Total Hip Replacement (THR). Surgical decompression was performed and patient had full recovery.

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Informed consent is vital to good surgical practice. Pain, sedative medication and psychological distress resulting from trauma are likely to adversely affect a patient's ability to understand and retain information thus impairing the quality of the consent process. This study aims to assess whether provision of written information improves trauma patient's recall of the risks associated with their surgery.

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For the first time the entire sequence of the mating behaviour of Antarctic krill (Euphausia superba) in the wild is captured on underwater video. This footage also provides evidence that mating can take place near the seafloor at depths of 400-700 m. This observation challenges the generally accepted concept of the pelagic lifestyle of krill.

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Antarctic krill embryos and larvae were experimentally exposed to 380 (control), 1000 and 2000 µatm pCO₂ in order to assess the possible impact of ocean acidification on early development of krill. No significant effects were detected on embryonic development or larval behaviour at 1000 µatm pCO₂; however, at 2000 µatm pCO₂ development was disrupted before gastrulation in 90 per cent of embryos, and no larvae hatched successfully. Our model projections demonstrated that Southern Ocean sea water pCO₂ could rise up to 1400 µatm in krill's depth range under the IPCC IS92a scenario by the year 2100 (atmospheric pCO₂ 788 µatm).

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The diversity of parasites found on Nyctiphanes simplex and Nematoscelis difficilis (Order Euphausiacea) was compared during 10 oceanographic cruises made off both coasts of the Baja California peninsula, Mexico. We tested the hypothesis that N. simplex has a more diverse parasitic assemblage than N.

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The Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) is bound by its Article II, 3 to follow an ecosystem approach to management. This approach has been extended to the application of a precautionary approach in the late 1980s. In our review, we deal primarily with the science-related aspects of CCAMLR and its development towards an ecosystem approach to the management of the living resources of the Southern Ocean.

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Polar organisms have adapted their seasonal cycles to the dynamic interface between ice and water. This interface ranges from the micrometre-sized brine channels within sea ice to the planetary-scale advance and retreat of sea ice. Polar marine ecosystems are particularly sensitive to climate change because small temperature differences can have large effects on the extent and thickness of sea ice.

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