Our Changing World for Thursday 5 August 2010

Butterfly House at Otago Museum

Even in the middle of winter, it's nearly 30°C at the top of Otago Museum's three level butterfly house, and the humidity hovers around 80%. The Tropical Forest is home to nearly 1000 exotic butterflies, which are imported from the Philippines and Costa Rica as pupae. Murray McGuigan, the living environments officer for the Otago Museum (pictured above. Images: Otago Museum) takes Alison Ballance on a tour of the popular exhibit, and explains what it takes to maintain the butterfly house's tropical climate, and how the butterflies are managed.

Knee Model

University of Auckland's Gait Laboratory at Sport and Exercise Science; and a screen shot from the analysis of Ruth Beran's gait (images: Desney Greybe)

An anatomically correct computer model of the knee which can be customised to a specific person has been developed by Auckland Bioengineering Institute'sVickie Shim and Kumar Mithraratne to provide accurate predictions about the impact of a knee injury without the need for surgery.

Ruth Beran meets them at the Sport and Exercise ScienceBiomechanicslab at the University of Auckland's Tamaki campus, to see how their model is generated. To do so, she volunteers to walk on special pressure plates, and have her gait measured by Adam Dooley and Desney Greybe. This analysis would feed into the model by providing information on the forces exerted on the knee due to the movement between the hip, femur, tibia and foot.

An MRI would then be performed, providing information on soft tissues, including ligaments, cartilage and the meniscus, to customise the knee model for a specific person. The model can then show how an injury occurred and identify the best treatment options, such as a knee brace or implant.

Paua Research in the East Otago Taiapure Local Fishery

The shoreline of Huriawa Peninsula, measuring paua length and taiapure sign (images: A. Ballance)

The East Otago Taiāpure-Local Fishery was gazetted in 1999, and a management committee appointed in 2001. A taiapure is defined in the Fisheries Act as 'a local management tool established in an area that has customarily been of special significance to an iwi or hapü as a source of food or for spiritual or cultural reasons. All fishing (including commercial fishing) can continue in a taiapure. This tool offers a way for Tängata Whenua to become involved in the management of both commercial and non-commercial fishing in their area. Another form of customary fisheries management is a mataitai area, in which only recreational fishing is permitted. Chris Hepburn is a post-doctoral fellow in the Department of Marine Sciences at the University of Otago. He is funded through the Foundation for Research Science and Technology's Te Tiaki Mahinga Kai project to provide research advice on three taiapure on the east coast of the South Island. Alison Ballance joins him at Huriawa Peninsula as he and a team of divers search for tagged paua, where she meets East Otago Taiapure Mangement Committee members Brendan Flack and Allan Anderson.

Paua research team including Allan Anderson (2nd left), Chris Hepburn (centre) and Brendan Flack (far right); paua marked with small green plastic tags, partially obscured by the growth of coralline (images: A. Ballance)

Vitamin C and Cancer

The essential nutrient Vitamin C, or ascorbate, was only isolated in 1932, but its presence in citrus foods meant that oranges were shown to prevent scurvy as far back as 1747. Captain Cook took sauerkraut on the Endeavour so his men could get enough of it, and the English navy later gave sailors a daily ration of lime juice for the same reason, although its efficacy was limited because lime juice contains far lower concentrations of Vitamin C.

Ruth Beran speaks with Margreet Vissers (left) and PhD student Caroline Kuiper (right) from the Free Radical Research group at the University of Otago, Christchurch who have found a mechanism which suggests that Vitamin C could play a far greater role than just preventing scurvy, it could also stop cancer.

They have shown that human endometrial tumours with low vitamin C levels had more of a protein called HIF-1 which allows them to survive in conditions of stress. Tumours were less able to accumulate vitamin C compared with normal healthy tissue, and the lower the levels of Vitamin C the larger the tumour. Their findings suggest that it is beneficial for people to have more Vitamin C.