Our Changing World for Thursday 17 February 2011
Sleep Apnoea - part 1
Maui Stuart before his diagnosis of sleep apnoea (left), and after (right) in the room where he had the overnight sleep study with Jessie Bakker (images: Maui Stuart and Ruth Beran)
In this two-part story, Ruth Beran meets Maui Stuart who was recently diagnosed with sleep apnoea after an overnight sleep study at WellSleep, a sleep investigation centre based at Wellington's Bowen Hospital.
Jessie Bakker from the University of Otago, Wellington who worked at WellSleep explains what sleep apnoea is, how it is diagnosed, what happens during a sleep study, and demonstrates the gold standard treatment - a continuous positive airways pressure (CPAP) machine.
A CPAP machine and leads used in overnight sleep studies(image: Ruth Beran)
Jessie Bakker recently led a study analysing why some people in the community are less likely to continue with CPAP treatment. The first part of the study was based on a questionnaire of 127 patients living in the Greater Wellington area, and found that ethnicity did not independently predict compliance with CPAP after measures like socioeconomic deprivation and education were factored in.
The second part of the study involved three focus groups where eight New Zealand Europeans, five Maori and five Pacific patients, and while discussions did touch on culturally-specific aspects, all groups discussed common problems like financial barriers to CPAP use, feeling overwhelmed with the CPAP educational material, and the importance of role models.
Maui Stuart benefited from the discussion group, and has been changing his life ever since he was diagnosed with sleep apnoea. He has continued with CPAP treatment, has changed his diet, and is now doing regular exercise. He has lost over 25 kilograms so far, and his goal is to swim the Cook Strait.
Katrin Hammerschmidt, left, and Caroline Rose with some of the bacterial cultures they grow for their experiments (image: Rainey group)
Why would a single-celled organism give up its ability to reproduce for the pleasure of being part of a larger, more complex structure? This is one of the big questions of evolutionary biology, and Massey University evolutionary geneticist Paul Rainey and his team (post-docs Katrin Hammerschmidt and Eric Libby and PhD student Caroline Rose) are trying to find some answers with the help of a well-studied soil bacterium. When cultured in the laboratory, some cells develop the ability to produce a sticky glue that holds them together in a thin mat, floating at the top of the liquid broth they live in. Producing the glue is costly to individual cells, but the cost is outweighed by the benefits of group membership which ensures access to oxygen at the surface. However, the mats are short-lived. Eventually, a new type of cell emerges which doesn't produce the glue but still takes advantage of the group benefits. These cheats prosper and ultimately weaken the mat to the point of collapse, to just then produce the adhesive again and start a new mat. The team proposes that the cheats are the equivalent of a reproductive cell starting a new generation and that the experiments illustrate one way of how single cells may have developed into more complex groups and organisms.
Sleep apnoea - part 2
In the second part of this two-part story, Ruth Beran meets Maui Stuart who was recently diagnosed with sleep apnoea after an overnight sleep study at WellSleep, a sleep investigation centre based at Wellington's Bowen Hospital.
Maui Stuart has been changing his life ever since he was diagnosed with sleep apnoea. He has continued with CPAP treatment, has changed his diet, and is now doing regular exercise. He has lost over 25 kilograms so far, and his goal is to swim the Cook Strait.
Space Physics from Antarctica
Craig Rodger(left, image: J.Dodgshun) from the Physics Department at the University of Otago is interested in how the sun's activity impacts Earth, and as part of that quest he is a member of a joint New Zealand-United Kingdom space physics project known as AARDDVARK, an acronym that stands for the Antarctic-Arctic Radiation-belt (Dynamic) Deposition - VLF Atmospheric Research Konsortium. Fifteen ground-based detectors in the Arctic and Antarctic provide continuous long-range observations of the lower-ionosphere using very low frequency radio waves, with the upper atmosphere serving as a gigantic energetic particle detector to observe and understand energy coupling between earth's atmosphere, the sun and space. One of these polar receivers is based at Arrival Heights in Antarctica, and Alison Ballance joins Craig Rodger at the laboratory to find out where the very low frequency radio waves come from, how they propagate around the earth's atmosphere and what they can tell us about solar energy. She discovers that the receiver has a dual purpose, as it also detects global lightning strikes that are fed into an international lightning detection system that goes by the acronym WWLLN (pronounced woollen).
Adelie Penguins in Antarctica - Special Web-Only Feature
Adelie penguins are an iconic Antarctic species, and as one of the Antarctic's most 'easily observable organisms' they have been the focus of long-term surveys. Phil Lyver from Landcare Research explains to Alison Ballance how a combination of aerial photography and ground-based monitoring are revealing population trends and evolutionary insights that are in turn being used in climate models to predict the impact of rising temperatures and changing sea ice regimes on Antarctic species. They spoke at Scott Base, just before the annual aerial census of Adelie penguin colonies on Ross Island and along the Victoria land coast.