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Marsden Fund NewsletterNo 17 September 2001Contents$29m allocated to new Marsden projects Darwin proved right on the origins of whitebait How stomach ulcer bacteria get from A to B...and stick there Reconstructing past environmental conditions from ancient kauri Taking students' safety seriously $29m allocated to new Marsden projectsA total of 82 new research projects will receive $29 million support over the next 3 years from the Marsden Fund, administered by the Royal Society of New Zealand. In their first year, the projects will receive $10 million, of which $1 million has been allocated to 20 "Fast-Start" researchers who are in the early stages of their research careers. The money for new projects is part of the $27.8 million commitment of Government money for cutting edge research - a $2 million increase on the previous year. Each successful project receives funding for 2 or 3 years. Applications to the Fund are very competitive. Of the 884 preliminary proposals (707 standard proposals and 177 Fast-Start proposals), 179 were asked to submit a full proposal. Overall, 9.3% of the total number of applications were successful. The Chair of the Marsden Committee, Professor Diana Hill, said, "I am delighted with the quality and range of the projects that we have been able to fund this year; they constitute some really exciting research. In particular, the Fast-Start initiative has been a resounding success in attracting high quality applications from outstanding young researchers. Many applications which were not successful this year were of a very high calibre. We certainly encourage those applicants to reapply next year." For further information on this year's grants, see http://www.rsnz.govt.nz/funding/marsden fund/ |
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| The Australian Brushtail Possum. Illustration by Bob Brockie |
Theorists worldwide have developed many mathematical models to describe relationships between predators and their prey and between diseases and their hosts. These equations explain and predict the likely spread of invading animals, parasites and diseases but often work better in theory than in practice. They have turned out to be of limited value in explaining and predicting the dynamics of populations in real-life New Zealand settings.
It is here that Marsden grant recipient and ecologist Dr Nigel Barlow of AgResearch, Lincoln, and his colleague Dr John Kean, step into the picture. They have sought to improve the usefulness of the models by adding new elements to the classical equations and testing them in the field. The new elements include things such as time-lags, the effects of weather on populations, the effects of habitat quality and its variation across the landscape, the way in which predators and parasites seek their prey, increased risks associated with dispersal, and so on. The ecologists are especially interested in the importance of dispersal within and among small patchy populations as they contribute to the dynamics of the encompassing "metapopulation".
Drs Barlow and Kean test-ran their new mathematical models against historical field data from Tb in possums, viral disease in rabbits, and the spread of parasitoids introduced to control common wasps. They also undertook fieldwork on lucerne weevil parasitoids to find out whether the model predictions for these held true. A high-powered vacuum cleaner featured in this work. Over a 3-year period, the machine was dragged across more than 20 farms between Christchurch and Lake Coleridge to sample weevils and their parasitoids in the leaf litter and soil. They found that lucerne weevils usually disperse to a distance of around 12 km, but this does not help the pest escape its biological control agent.
After 3 years work, the improved models were found to better explain the puzzling
behaviour and patchy distribution of Tb in possums, the persistence of
RHD virus (formerly known as rabbit calicivirus) in rabbits, why the parasitoid
introduced to control weevils has worked but the one introduced to control wasps
has not, and why there is often a lag before an invading or introduced species
becomes obvious. The models also suggest why some rare species survive when
theoretically they should have become extinct.
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An introduced parasitoid sizing up a lucerne weevil |
The research has been very useful in making sense of interactions between many animals and in deciding which kinds of models might best be applied in real life.
These mathematical insights will be a powerful resource for biosecurity, biological control, and conservation.
For further information, contact Dr Nigel Barlow, AgResearch, P. O. Box 60, Lincoln Tel: (03) 983 3974 Email: nigel.barlow@agresearch.co.nz
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| Photo courtesy of the West Coast Times |
Our common inanga (otherwise known as whitebait, galaxiid fish, or Galaxias maculatus) also swim in the rivers of Patagonia, the Falklands, western and south-eastern Australia, Tasmania, and Lord Howe Island.
Biologists have long been puzzled by this far-flung distribution. How could freshwater fish swim so far across the seas? Darwin suggested that when the Antarctic was a much warmer place inanga lived in its rivers and from there invaded these southern countries and islands. Other biologists suggested that, as these fish are sea-going for part of their lives, they may more recently have simply swum from one continent or island to another. Others have argued that these populations may even still have the potential to exchange genes.
Years of close examination and enzyme analysis failed to throw much light on the question, but now DNA has come to the party. DNA allows biologists to measure the genetic distance between populations and to approximately date ancient evolutionary events.
Marsden-funded researchers Drs Graham Wallis and Jon Waters from the University of Otago, in collaboration with Dr Lucette Dijkstra from NIWA, looked at mitochondrial DNA from 163 inanga from Chile, Tasmania and from several New Zealand rivers.
Consistent with Darwin's hypothesis, they found large differences in the DNA of Chilean, Tasmanian and New Zealand inanga. The DNA clock suggests that the large South American/Australasian genetic differences originated at the very most 30 million years ago, but certainly not 80 million years ago, when Gondwanaland broke up. New Zealand and Tasmanian whitebait are more closely related to each other than they are to the South American whitebait, suggesting they evolved apart more recently.
The DNA shows no evidence of "genetic structuring" in Galaxias
maculatus from various New Zealand river systems. That is to say that the
fish from various New Zealand rivers interbreed with each other from one end
of the country to the other, and share the same gene pool. The measurements
suggest that sea-going juveniles do not necessarily return to the same estuaries
and rivers they hatched in or where their parents lived. However, the team found
no evidence of present-day whitebait exchanging genes with Australian whitebait.
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One single fish stood out from the rest. Although collected in the Bay of Islands, this fish was similar to, though not identical with, the Tasmanian types. Dr Wallis and his team suggest that an ancestor of this fish arrived from Australia within the last million years or so, giving us evidence of trans-Tasman dispersal, albeit a rare event.
For further information, contact Dr Graham Wallis, Department of Zoology, University of Otago, P. O. Box 56, Dunedin Tel: (03) 479 7984 Email: graham.wallis@stonebow.otago.ac.nz
Eighty-two of the 179 full proposals have been offered funding (62 standard applications and 20 Fast-Starts). Further details of the applications and a list of successful applications are on the Marsden Fund web page on the Royal Society of New Zealand website, http://www.rsnz.org/funding/marsden_fund/
This is the seventh application round for the Marsden Fund. The Marsden Committee was impressed with the standard of proposals but regrets that within the available resources not all the excellent proposals could be funded. The Committee also noted that, with the maturing of the Fund, a problem can arise with applicants putting forward proposals which overlap too much with continuing contracts. It must be remembered that the funding is for new developments in research.
An important feature this year has been an increase in the funding requests (a total of $32.9 million was requested for the first year of all full proposals) and also in the average funding awarded. The Marsden Committee has endeavoured to control costs but at the same time provide research groups with adequate resources to do the research. The average annual funding per research grant has increased by 11% and part of this is the increase in funding levels for postdoctoral fellows and postgraduate students, to keep these prestigious grants competitive with other sources of fellowships and scholarships. In addition, the increases have been much larger in the social sciences, humanities and some life science areas because of more realistic requests for the time input of researchers and of some supporting expenses. The percentage of successful applications is not constant over all panels as it depends on the funding awarded to the top proposals. For the smaller panels, a small absolute change in the number of successful proposals can cause considerable changes in this percentage.
The profile of the applicants, analysed by years since the highest postgraduate degree, is similar to last year for the "all investigators" category but there has been a shift from associate to principal investigators for the people within 5 years of receiving their postgraduate degree. This appears to be the influence of the Fast-Start programme having the intended effect of encouraging people at the start of their careers to participate more fully in research.
The Marsden Committee has become aware that, despite the information being published and available on the web, many people do not know about the processes followed in panel assessment meetings. Panellists are provided with the proposals well in advance of the meetings with the guidelines for assessment. For the full proposals they also receive the referees' reports and applicants' responses to those reports. Before the meeting, they provide their initial grades for the proposals and this information is collected and averaged to give an initial ranking. This leaves time at the meeting to discuss any proposals where there is not general agreement on the grades, and some conclusion to be reached.
The proposals near the top of the ranking are evaluated to see if there is certainty about whether they should be in the successful group and there is always a great deal of discussion about the relative merits of those proposals in the vicinity of the cut-off. Because of the large number of proposals to assess in the preliminary proposal meeting, those proposals which are given a low grade by all panellists are not discussed further.
Conflicts of interest are recorded and the Royal Society and the Committee take these issues very seriously. Those panellists who are applicants (or have a close association with applicants) leave the meeting during the discussion and do not find out the decision until the results are announced to all applicants. Action on other conflicts of interest, such as being a supervisor or collaborator in the past, is decided by the convenor, and the panellists can be asked to leave the meeting, to stay silent or to comment on technical matters only. In such cases of close conflict of interest the panellist does not grade the proposal. By the end of the meeting, the issues have been considered very thoroughly.
Marsden Fund staff and, as an observer, the Chair of the Marsden Committee (or her representative) attend all meetings to ensure that proper processes are followed.
The Marsden Fund is continuing to run its "Job Search" website. In its first year of operation, 60 postdoctoral and postgraduate positions were listed for Marsden contracts. The site was extensively advertised last year; your help in reminding people about it by displaying the enclosed flyer would be appreciated.
We welcome Cameron Crabb, who has joined the Royal Society staff and will be looking after the Marsden Fund database and administering the Job Search website. We have a pilot scheme operating to record publications from Marsden research and publish the lists on the web so that this can be a resource for others. Cameron will also be in charge of this once it is operating.
In due course, Cameron will also be looking after the Royal Society's website and assisting with IT support for the Society.
In the last newsletter I mentioned that Dr Andrea Knox was temporarily assisting in research assessment. We are delighted to announce that she has taken on the role of Evaluation Officer for the Royal Society. She will be involved in evaluation of the contestable funds administered by the Royal Society.
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From left to right: PhD student Norman Ragg, Masters student |
Technically speaking, paua, or abalones, are snails. Paua have been relatively untouched by evolutionary processes which have transformed other molluscs. In their characteristic shell openings, which allow the flow of seawater for oxygen supply, and in their possession of paired gills and kidneys, paua have retained features of an ancient body plan.
The research, directed by Associate Professor Harry Taylor at Canterbury University, has focused on the design of the circulatory and respiratory systems and their role in transporting oxygen and other metabolic products around the body. What happens physiologically when paua clamp on to a rock is of particular interest, since this is the creature's principal means of defence.
Earlier work had suggested that paua were poorly supplied with blood. Paua gatherers and consumers may be surprised to learn that in fact paua have a great deal of blood, normally about 50% of their flesh weight. But prolonged clamping reduces the volume by about 20%, a response that may enable the threatened animal to completely withdraw into the shell cavity. During this process, the blood, which is coloured blue by an oxygen-transporting protein called haemocyanin, becomes more concentrated as water and salts are excreted.
Fluorescent particles, radioisotopes and ultrasound are being used to estimate the flow of blood to the tissues of the paua in different physiological states. These methods have revealed the existence of a direct connection between the main arteries and the veins that allows blood to bypass the foot and shell muscles altogether. The shell is connected to the muscular foot by the adductor muscle, which draws the shell down tight over the soft body during clamping. Despite the high energy demands of clamping, the blood flow to the working muscle is extremely restricted and it must switch over to anaerobic respiration during prolonged clamping. The researchers are investigating how the paua is able to eke out oxygen reserves, and the role of the blood in clearing the unusual anaerobic products which accumulate under such conditions.
Sophisticated techniques using electron and optical microscopes have enabled the team to build a detailed "road map" of the circulatory system. This has uncovered some surprising features. For example, the left kidney not only has a different anatomy from the right, but it is supplied by a single set of blood vessels in which the direction of flow reverses with each beat of the heart.
By the end of the project the team hopes to provide an integrated description of the functioning of the circulatory and respiratory systems of paua and to understand why other snails abandoned this prototype.
For further information, contact Associate Professor Harry Taylor, Department of Zoology, University of Canterbury, Private Bag 4800, Christchurch, Tel: (03) 364 2861 Email: h.taylor@zool.canterbury.ac.nz
Principal Investigators: Professor Peter Hunter and Dr Merryn Tawhai, Bioengineering Research Group, University of Auckland
Marsden Grant: $360,000 over 3 years
An Auckland research team of engineers and mathematical modellers will combine their skills to study the flow of air through lungs. This research will provide the foundation for a major new approach to understanding and treating diseases of the lung.
Because lungs are relatively inaccessible and difficult to image, it is not currently possible to directly assess lung tissue damage or response to treatment. This has prompted the development of mathematical models to interpret lung function, but past models have had limited success because of their simplicity.
The Auckland research team under Professor Peter Hunter and Dr Merryn Tawhai will develop a detailed lung model that links molecular activities in cells to the whole function of the lung. This model will be used to investigate how healthy and diseased lungs function. The research team will distribute its results to the international Lung Physiome Project, part of a wider project to simulate the physiology of the whole body. The aim is to couple the wealth of genomic and cellular data now becoming available to computational methods capable of dealing with the complex processes within the lungs. These new methods bring together many disciplines, including engineering, chemistry, physics, mathematics and biology.
Principal Investigator: Dr Michelle Glass, Division of Pharmacology and Clinical Pharmacology, University of Auckland
Fast-Start Marsden grant: $100,000 over 2 years
Dr Michelle Glass will study how opioid pain-killing drugs like morphine affect cells. Morphine is the standard drug for severe pain relief but patients frequently suffer from serious side effects, particularly nausea and sedation, which limit its use.
Morphine acts by binding to specific receptors on brain cells, which then trigger several processes inside the cell that lead to reduced pain, but also to unwanted side effects. These processes are activated through a group of molecules called G proteins.
Dr Glass will artificially generate the cell membrane fragments containing the morphine receptors and add different combinations of G proteins and opioids. This will allow her to determine which G proteins are activated by which opioids, thus differentiating the pain-relieving processes from those that cause side effects. Dr Glass' work will ultimately facilitate the development of better pain-killing drugs with fewer side effects.
Principal Investigators: Ms Linda Waimarie Nikora, Maori & Psychology Research Unit, Psychology Department, University of Waikato; Professor Ngahuia Te Awekotuku, Maori Studies, Victoria University of Wellington; and Ms Ngarino Ellis, Department of Art History, University of Auckland
Marsden grant: $445,000 over 3 years
Ta Moko, the form of body adornment unique to Maori, is the focus of a research project based at the University of Waikato. The aim is to produce an in-depth account of Maori use of Ta Moko.
Historically, Ta Moko involved a deep scarring of the skin and the insertion of colour. The uhi (chisel) that was traditionally used has been replaced by the western needle cluster and electric gun, although use of the uhi is currently being revived. Unlike tattooing in other cultures, Ta Moko involves carving the skin rather than puncturing it.
Maori use of Ta Moko declined following European colonisation. Now, with the revival of Maori commitment to cultural self-determination, interest in this form of taonga is reviving. The research will encompass this revival and explore social and political issues for the increasing numbers of Maori wearing forms of Ta Moko.
The researchers are in discussions with Maori, which will continue throughout the project.
Principal Investigator: Associate Professor Annie Goldson, Department of Film, Television and Media Studies, University of Auckland
Marsden grant: $230,000 over 3 years
Associate Professor Annie Goldson has won a Marsden grant to explore issues surrounding documentaries on human rights and international law. This interest stemmed from her experience of producing her recent work, the highly acclaimed documentary Punitive Damage, which screened on New Zealand television and in cinemas here and around the world. Punitive Damage concerns the death of a New Zealander at the hands of the Indonesian military during their occupation of East Timor, and the subsequent attempts to get the case heard under international law.
While distributing Punitive Damage, Professor Goldson came across a series of documentaries that bore similarities to her own. Calling the Ghosts is the story of two Bosnian women who were repeatedly raped by Serbian paramilitaries and who testified before the International War Crimes Tribunal at The Hague, while Long Night's Journey into Day focuses on case studies heard before the Truth and Reconciliation Commission in South Africa.
In her analysis, Professor Goldson will propose and explore three theses. First, she will argue that these films are part of a new genre of human rights documentaries based on international law, that use the device of legal testimony from witnesses and victims to explore a situation of grievous human rights abuses. Second, she suggests that the documentaries and the legal processes that they represent are part of a new "global morality" that has emerged in the post Cold War era, and that returns to an idea of universal human rights. Third, she explores the reasons why women figure prominently in the documentaries, as both central "characters" and as director/producers. Professor Goldson will also interview the three film-makers involved and incorporate their reflections on producing and distributing their work into the body of the research.
Professor Goldson's research will be publicised as a book with an accompanying video documentary.
Principal Investigators: Dr Tim Naish, Institute of Geological and Nuclear Sciences, Lower Hutt, and Professor Peter Barrett, School of Earth Sciences, Victoria University of Wellington
Marsden grant: $390,000 over 3 years
The stability of the East and West Antarctic ice sheets in the context of global warming, is of critical importance to humanity. If they melted completely, the sea would rise 65 m, inundating huge areas of productive coastal plains. Latest information from the Intergovernmental Panel on Climate Change predicts a 2 - 6 degree Celsius increase in temperatures by the end of of this century. A concern is that changes of this order could destabilise the Antarctic ice sheets and lead to their breakup. However, no one knows for sure to what extent this might happen.
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The fundamental behaviour of ice sheets and the conditions under which they might melt is poorly understood. Dr Naish, Professor Barrett and collaborators have hypothesised that the East Antarctic ice sheet was unstable 35 - 15 million years ago when planetary temperatures were 3 - 4 degrees warmer than at present. They plan to analyse 1500 m of sediment core recovered from McMurdo Sound during the past 3 years by the multi-national Cape Roberts Project, and to establish the character and periodicity of climatic changes and associated advances and retreats of the ice sheets in that 20 million year period.
This information will enable researchers to establish the extent of ice sheet changes when the planet was warmer and to better predict how the Antarctic ice sheets will react to continued global warming.
Principal Investigator: Professor Murray McEwan, Department of Chemistry, University of Canterbury
Marsden grant: $480,000 over 3 years
The techniques used to study organic molecules existing in gigantic interstellar gas clouds and in the atmospheres of other planets and moons will be applied for medical and environmental benefit here on Earth.
Professor McEwan's proposal has two goals. The first is to examine how such molecules can be made in the extraterrestrial environment under conditions that are so cold ( -223 to -263 degrees Celsius) that conventional chemistry virtually stops. It was once thought that no chemistry was possible in this hostile medium, but close to 120 different molecules and ions have now been identified. These gas clouds, which are loosely held together by gravity, are so large that they contain vastly greater quantities of organic material than are present on Earth, even though the concentration of matter is very low. Professor McEwan will be specifically focusing on reactions with carbon, the key element in organic molecules on which all life forms are based.
The second goal is to develop the instrumentation so that it can be used to detect trace amounts of very volatile organic compounds arising from a wide range of processes. Hence, the technique can be used to diagnose disease by detecting tiny amounts of certain compounds in the breath. It may also be applied to measuring pollution and to checking food quality. This part of the research work is being carried out in collaboration with Christchurch Hospital.
Principal Investigator: Dr David Saul, School of Biological Sciences, University of Auckland
Marsden grant: $475,000 over 3 years
How did life originate on Earth? Two opposing views on the origins of life are the "hot start" and "cold start" theories. Some hold that Earth's volcanic past indicates that life emerged during a period when the temperature was much higher than now. The bombardment of Earth by meteors when the solar system was still settling down would have repeatedly boiled the oceans, and it has been argued that deep oceanic hydrothermal vents may have been the only stable environments in which life could emerge. The recent discovery of organisms growing at or above 95 degrees Celsius would seem to support this idea. Others say that the evidence for life beginning in high temperatures is not strong and that a cold start was just as likely.
The Marsden-funded team from Auckland University will endeavour to produce their own evidence to answer biology's fundamental question. Improvements in computational power and techniques in molecular biology allow research techniques that would have been bio-fiction not so long ago. They intend to infer the sequence of these ancient genes by extrapolating back from those found in contemporary bacteria. Then, they will artificially reproduce these putative genes and, in turn, produce the proteins encoded by them. The protein products will be tested to see if they are adapted to function in a hot or a cold environment, indicating the optimum temperature for growth of these early organisms.
Principal Investigator: Dr Sophie Tomlinson, English Department, University of Auckland
Fast-Start Marsden grant: $100,000 over 2 years
Most scholars identify the Stuart Restoration of 1660 as the time when acting first emerged as a profession available to women. But Dr Sophie Tomlinson argues that women's involvement in theatre and the portrayal of female characters became a public issue before that time.
By means of a scholarly book and a collaborative edition of three 17th century plays, she will show how a lively debate about women actors arose in response to the innovative performances of two foreign queens at the early Stuart courts, Anne of Denmark and Henrietta Maria of France, in the early 1600s. Dr Tomlinson argues that this controversy resulted in a new appreciation of women's ingenuity and wit, and more realistic portrayals of women. It also enabled female playwrights in England to gain acceptance.
Male playwrights were influenced by the debate too. For instance, John Fletcher's comedy The Wild-Goose Chase (1621), consciously revises the model of gender relations in Shakespeare's The Taming of the Shrew (1592) in order to appeal to the sophisticated audiences of Jacobean private theatres. Tomlinson and her young team of scholars are planning to publish an edition of this play, together with editions of James Shirley's The Bird in a Cage (1633) and Margaret Cavendish's The Convent of Pleasure (1668). Together, the monographs and the edition in which Dr Tomlinson is engaged, will rewrite the history of 17th century theatre from the perspective of its female participants. This promises to significantly alter our understanding of women and performance in 17th century England.
Principal Investigator: Dr Iain Lamont, Department of Biochemistry, University of Otago
Marsden grant: $420,000 over 3 years
Dr Iain Lamont and his colleagues at the University of Otago will study how a potentially harmful species of bacteria called Pseudomonas aeruginosa receives information from its surroundings.
These micro-organisms are widespread in nature and can infect people who have severe burns or a compromised immune system. In order to grow, P. aeruginosa bacteria need to scavenge iron from their surroundings. They do this by secreting a chemical called pyoverdine, which binds to the iron and then carries it back into the bacterium.
Dr Lamont's group has discovered that, in addition to shuttling back and forth across the cell membrane, pyoverdine sends signals through three connected proteins which span the inner and outer cell membranes. This activates certain genes and the bacteria produce substances that enable them to multiply and cause disease. The researchers will identify which genes are activated and analyse precisely how the signal activates them.
The pyoverdine system provides a model for how many types of bacteria might respond to their environment. The proposed studies may, therefore, help us understand how to stop or inhibit bacterial infections.
Principal Investigator: Dr Sheila Thornton, Department of Zoology, University of Otago
Fast-Start Marsden grant: $100,000 over 2 years
How long can you hold your breath? Thirty seconds, perhaps a minute? Now imagine that not only are you holding your breath, but you're exercising hard. Weddell seals do this for several hours a day. They hold their breath for up to 40 minutes, dive as deep as 400 m and catch all their food while doing it. And after all this, they don't even seem to be out of breath. How can seals dive for so long but not run out of oxygen?
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The tissues of the seal seem to reduce their requirements for oxygen during diving. But this doesn't involve the creation of an "oxygen debt", which is what happens to humans that try the same thing. Blood flow to peripheral tissues is reduced and the heart rate drops while seals are swimming, foraging and feeding underwater. Somehow seals are able to make the oxygen they store in their muscles go much further than might be expected.
Mitochondria are probably the key to this behaviour. They are found within cells and are the places where the energy in food is extracted and where oxygen is consumed. Mitochondria work by creating a chemical "gradient" across their membrane. Energy stored in this gradient is harnessed to drive pumps which make an important molecule called ATP. However, the membrane enveloping the mitochondria and separating it from the rest of the cell is fairly leaky and in most mammals perhaps half of the energy is lost. It seems likely that the mitochondria in diving seals are much less prone to these leaks. By examining seal mitochondria in specially designed equipment, it will be possible to see what happens to them under diving conditions when pressure increases and the oxygen supply decreases.
Principal Investigators: Associate Professor Dave Kelly and Dr Matthew Turnbull, Plant & Microbial Sciences, University of Canterbury
Marsden grant: $486,000 over 3 years
Southern beech forests of New Zealand have a unique interaction with the tiny, sooty beech scale insect that sucks sap from these trees and produces significant quantities of honeydew. This excreted honeydew is extremely important to a large range of consumers within these forests, including native birds, reptiles, invertebrates, fungi and many soil micro-organisms.
However, the actual nature of the interaction between the insect and the beech trees is not well understood. In particular, the extent to which the honeydew scale insect affects the overall productivity of these forest systems has not been determined. It has been estimated that the scale insects extract an astonishing 32% of the energy produced by photosynthesis from lowland beech forests, but the trees that support them appear just as healthy as uninfested trees.
Associate Professor Kelly and Dr Turnbull will investigate the physiology and ecology of this important and unusual interaction. They propose that the insect does not harm its host tree, but rather that the host is induced to increase photosynthesis by the extra demand for sugars.
Results from this study will advance our fundamental understanding of the impact that insect feeding has on forest function. This will determine whether an insect can cause large amounts of extra photosynthesis to occur and, as such, be regarded as a "primary producer". If this were the case, then this distinctly New Zealand phenomenon would prove to be very unusual on a world scale. The study will also help determine the likely responses of beech ecosystems to global climate change. If their theory is correct, heavily infested forests may cope better with higher temperatures and levels of atmospheric carbon dioxide.
Principal Investigators: Associate Professor Bruce Smaill, Faculty of Medical and Health Sciences, and Associate Professor Andrew Pullan, Department of Engineering Science, University of Auckland
Marsden grant: $585,000 over 3 years
A beating heart is a sophisticated muscular pump in which the pumping action occurs by regular contractions of the heart muscle. These contractions are triggered by waves of electrical activity that sweep through the four chambers of the heart in a co-ordinated fashion. This ordered rhythm is sometimes disturbed by electrical waves that cycle rapidly within a particular region of the heart. These "re-entrant arrhythmias" are often provoked by a heart attack and can progress to complete disruption of the heart rhythm, called "ventricular fibrillation".
Physiologists and engineers from the University of Auckland are working together to understand more about these potentially life-threatening heart rhythm disturbances.
Electrical activation at the level of individual cells within the heart is fairly well understood and techniques have been developed for recording electrical events on the surface of the heart. However, there is currently much less knowledge about the mechanisms that cause re-entrant arrhythmia and fibrillation, as these have an effect throughout the entire heart.
The Auckland researchers plan to develop experimental probes, which will use laser light to visualise electrical activity inside the muscle of the heart wall, rather than just on the surface, and to retrace the paths that electrical waves follow during re-entrant arrhythmia. These results, together with a detailed study of the structure of cardiac muscle, will be combined to build up a computer model. Arrhythmias and fibrillations can then be generated within the model, simulating a heart attack. The combination of the experimental study and the computer modelling will provide a better understanding of why these heart rhythm disturbances occur.
Principal Investigators: Dr Kathy Schwinn and Dr Kevin Davies, Crop & Food Research, Palmerston North
Marsden grant: $455,000 over 3 years
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Many flowers have pigmentation patterns involving stripes, spots or irregular
patches. To have areas on the same petal with and without colour, the plant
needs to turn on pigment production in some cells, while keeping it turned off
in similar neighbouring cells. We know how the typical red and blue pigments
are made and have some knowledge of the way in which the plant controls this
pigment production. However, we still do not know how the complex patterns of
petal pigmentation are formed.
Pigments are made by specialised proteins inside plant cells. Different proteins make different pigments, so the colour of a cell is determined by which mix of proteins it produces. Ultimately, the production of proteins is controlled by the plant's genes, but how do two genetically identical cells of the same plant produce different sets of proteins?
We now know that individual genes can be turned on or off. In its "on" state, a gene tells the cell to produce a particular protein. This project will tackle the fundamental question of how genes are turned on and off, and how these instructions are coordinated between cells to make flowers with striped and spotted patterns.
Principal Investigator: Professor Vaughan Jones, New Zealand Mathematics Research Institute and Auckland University.
Other New Zealand contributing organisations: University of Auckland and Victoria University of Wellington
Marsden grant: $261,000 over 3 years
The New Zealand Mathematics Research Institute will conduct a series of workshops that will bring some of the world's best mathematicians together in New Zealand to work with local researchers and graduate students. The Institute is an independent organisation headed by Professor Vaughan Jones FRS FRSNZ, the New Zealand born and educated mathematician who was the first recipient of the New Zealand Science and Technology Gold Medal (since renamed the Rutherford Medal) and who remains the only person from a Southern Hemisphere country to have received the Fields Medal, which is the equivalent of a Nobel Prize for mathematics. Professor Jones is based at the University of California, Berkeley, but maintains a permanent appointment as Distinguished Alumni Professor at Auckland University. For some time now, he has spent a part of each year in New Zealand leading these research workshops. His eminence on the world stage of mathematics has enabled him to attract an impressive group of scholars to participate, providing excellent research-level training for New Zealand graduate students. The workshops have also attracted researchers and students from Australia and have increased international awareness of the research strength that exists in this country.
Principal Investigator: Dr Uwe Morgenstern, Institute of Geological and Nuclear Sciences, Lower Hutt
Marsden grant: $540,000 over 3 years
Core samples taken from ice sheets, particularly those in polar latitudes, vary at different depths in their content of greenhouse gases, dust, aerosols, and other substances implicated in climatic changes on Earth over the past hundreds of thousands of years.
To obtain a more comprehensive global picture of changes in Earth's climate, especially over the last few hundred years when human effects on natural processes have become significant, attention is now turning to mid to low latitude ice caps, which better characterise changes in the climate system across the planet. But scientists are lacking a suitable method to date ice layers in the relatively short time range of 100 - 1000 years. The most promising possibility is to use radioactive dating techniques based on a short-lived isotope of silicon, which is produced in the upper atmosphere through cosmic ray collisions, and is brought down to Earth in rain and snow.
Dr Morgenstern and collaborators will investigate the viability of this method.
They will first make accurate measurements of the "half-life" of the
isotope (how long it takes for the radioactivity of the isotope to reduce by
half) and differences in its deposition rate at various sites. With this information,
they will test the new dating method against previously dated polar ice cores,
and then apply the method to mid to low latitude ice caps and glaciers to distinguish
regional patterns of natural versus human-induced climatic changes.
Principal Investigator: Professor Les Oxley, Department of Economics, University of Waikato
Marsden grant: $250,000 over 3 years
Until recently, efforts to create more economic growth were focused on using more machines. However, with the growing importance of knowledge in the economy, the focus has moved towards the role of human capital in the growth process. Knowledge differences give some people more ability to contribute to the economy and society in the future than others. But how do you measure the knowledge embodied in human beings?
This task, as the Economist has remarked, is far from simple and certainly incomplete. To date, all popular measures have been based on past educational achievement, for example, years of schooling. However, such measures have been of limited use in explaining the performance of developed economies such as New Zealand.
In this Marsden project, Professor Oxley and his associates will attempt to construct a forward-looking measure of human capital by combining the traditional educational approach with a model that takes into account people's future earnings. The outcome of this work may give a better understanding of the role of human capital in the economy and provide guidance for appropriate policies.
A research programme, kick-started with a Marsden grant, has investigated how bacteria cause gastric disease in humans and animals.
Helicobacter bacteria stick to the stomach walls and produce toxins which damage the cells of the lining, enabling the organism to extract nutrients. As well as having "stickability", to be successful, these bacteria also have to be strong swimmers. They may need to migrate to greener pastures on the stomach lining through turbulent and acidic stomach contents. Massey University microbiologist, Dr Paul O'Toole, and his collaborators here and overseas, have been examining both characteristics in two Helicobacter species, H. mustelae and H. pylori, which cause gastric disease in ferrets and humans, respectively.
It had been thought that H. mustelae was absent from New Zealand ferret populations, but researchers were able to find animals colonised by the bacteria. They analysed repetitive regions in the bacterial chromosomes, which showed that the bacterium is able to vary the make-up of one of its surface proteins, Hsr, in order to fool the ferret's immune system. This effectively makes the bacteria invisible to the animal's defence forces. After a while, however, the immune system catches on and resumes attack.
The Hsr protein virtually covers the bacterial cell surface and might, therefore,
be expected to help the micro-organism stick to the stomach lining. However,
the team found that when Hsr was "knocked out" of the bacteria, it
did not prevent them from adhering to the stomach. This might suggest that the
only role of this abundant surface protein is that of "immune decoy",
but there is a possibility that the protein may also be involved in the transport
of nutrients into the cell. Researchers are currently testing this idea.
The adhesion function of proteins in H. pylori, the bacteria which cause stomach ulcers in humans, is reasonably well understood. There is a family of 32 different "sticking" proteins in the genome. So far, Dr O'Toole and colleagues have instead concentrated on the swimming ability of this species. The whip-like tail or flagellum that enables H. pylori to move so powerfully is constructed on the exterior cell wall from protein "building blocks" made inside the cell. These have to be transported outside through the cell membranes and wall. Exactly how they get there and where the energy comes from to do it, is of particular interest to the researchers.
Typically, around forty genes are required to direct the export and assemblage of flagella in single-celled organisms. The team is able to cross reference these gene sequences with the H. pylori genome, to determine which genes are present and which are missing. PhD student Steffen Porwollik has focused on a particular region of the H. pylori chromosome that encodes a protein involved in exporting the sub-units of the flagellum.
An exciting discovery is that certain proteins made in the cell, including one of the 32 family members used to secure the bacteria to the stomach lining, appear to hitch a ride out of the cell on the flagellum components. This energy-efficient transport system is being further investigated.
Although the damage caused to stomach cells by H. mustelae and H. pylori is very similar, the two bacteria appear to function differently, evidenced by the presence of Hsr in one and a family of adhesive proteins in the other. Both species differ from "model" textbook bacteria in having smaller genomes and therefore smaller protein repertoires. Understanding the details of their pathogenic mechanisms - how they encode, manufacture and transport proteins, and how they adapt to the host response has fundamental relevance for other cell biology studies. Better treatment of stomach ulcers may be a bonus.
For further information, contact Dr Paul O'Toole, Institute of Molecular BioSciences, Massey University, Private Bag 11-222, Palmerston North Tel: (06) 350 4998 Email: P.W.O'Toole@Massey.ac.nz
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| Dr Palmer standing in a drained peat bog area containing an extensive network of decayed in situ stumps and peg roots that now protrude above the shrunken peat layer. |
Kauri (Agathis australis) is widely known throughout New Zealand for its spectacular shape and size (with trunks more than 5 m in diameter!) as well as its timber properties. The restricted distribution of the species to northern parts of the country shows its tropical affinity. Our species is a southern outlier from the family group Araucariaceae and is a classic example of our relic Gondwanaland heritage.
When the great supercontinent of Gondwanaland broke up, New Zealand finally split from Australia, taking with it the conifer forests of that time, which have since become part of our unique native vegetation. One of those species, the prized kauri, has remained unchanged since separation 60 - 80 million years ago, when dinosaurs still foraged beneath their giant canopies.
In the 300 km stretch from Hamilton to Ninety-Mile Beach, there are peat bogs
containing, in some cases, perfectly preserved kauri stumps, logs and root plates.
The wood has resulted in a small industry producing high value ornaments and
furniture. Some of these forest remnants are at least 40,000 years old, which
is approaching the limit for radiocarbon-dating techniques. The wood was preserved
in the acidic and anaerobic conditions of the waterlogged peat burial grounds,
which prevented degeneration by insects, fungi, bacteria and oxygen-driven chemical
reactions.
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| Dr Jonathan Palmer and Mr Dave Stewart looking at a kauri
cross- section about to be sent for detailed tree-ring analysis. This tree was radiocarbon dated as being buried for over 40,000 years. |
Removing a buried kauri log from a peat bog.
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The extensive range of locations found to contain preserved wood has caused great local debate about the possible causes. Now, the findings of a Marsden-funded programme, led by Lincoln University plant palaeoecologist Dr Jonathan Palmer, have provided some intriguing insights. He and his collaborators, Associate Professor John Ogden (Auckland University), Dr Alan Hogg (Waikato University) and Drs Phil Tonkin and Xiong Limin (Lincoln University) have investigated the ages and distribution of these subfossil kauri in order to decode the cryptic record they form of our past climate.
When the radiocarbon ages of kauri wood taken from the bogs are graphed, a clear pattern emerges. There is a marked gap in the preservation of kauri between 8,000 and 20,000 years ago (see graph). The preservation periods either side of the gap span thousands of years, and several generations of trees can be found at the same site. Dr Palmer and the research team believe that this is linked to climate changes and associated sea-level fluctuations.
For example, during the last glacial event, which ended about 10,000 years
ago, the sea level was about 120m lower than today. At the end of the glaciation,
sea levels started rising again. Our western coastlines have persistent onshore
winds, but today, coastal dunes are constrained by the cliffs and adjacent hills,
limiting their spread inland. However, the effect of the sea-level rise initially
may have been the accumulation of a ramp-like sand mass, so that dunes could
migrate eastwards, partially burying the older landscape. Moving dunes can quickly
build thick sand masses that bury forests and alter drainage patterns.
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| Ages of ancient kauri logs. Bar heights represent the numbers of logs found of a particular age |
The travelling sand mass may leave little sign of its passing. The only evidence is a succession of thin sand sheets overlying the stumps of a buried forest.
Around the margins of many bog sites, successive generations of kauri trees were gradually colonising further and further towards the centre as sediment and tree material accumulated. However, this process was abruptly halted by rising water levels caused by the dunes or by impeded river drainage from raised sea levels. The result was that the trees were drowned and we find sites with stumps looking like a cut forest, the wood not underwater having rotted away. Under the stumps and towards the centre, we also find logs of the older generations. Peat development continued in the bog and eventually buried the stumps.
The team's findings illustrate the dramatic, though delayed environmental effects of sea-level changes. The period of time when kauri were not preserved coincides with a cold period which has been well-defined by ice core studies. However, the periods of kauri preservation do not match the timing of transitions from cold to warm periods, but begin some time later, after the migrating dunes have had their effect. The extent of the sand dunes and their mobility after a delayed period of time, was a major and unlooked for discovery which will have a bearing on future climate change scenarios.
Analysis of the tree rings is continuing and will provide a more detailed record of the climate during preservation periods. The ongoing archive collection of kauri cross-sections now held at The Kauri Museum at Matakohe in Northland will be a resource for other scientific studies.
For further information, contact Associate Professor John Ogden, School for Environmental and Marine Sciences, University of Auckland, Private Bag 92-019, Auckland, Tel: (09) 373 7599 ext 6624 Email: j.ogden@auckland.ac.nz
A nationwide study of 821 students in 107 secondary schools found that one-third of students could not categorically claim that they felt safe at school. Further, only 5% of students and 8% of staff respondents perceived that lesbian, gay or bisexual students would feel safe at their school. The survey was carried out by the Children's Issues Centre in Dunedin and was funded by a Marsden grant. Project Manager Dr Karen Nairn, a former teacher, says that these results are worrying in light of concerns about the links between bullying and youth suicide.
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| Dr Karen Nairn |
The survey, initiated by Professor Anne Smith, included questions about four sets of rights contained in the United Nations Convention on the Rights of the Child: specifically, young people's rights to participate in decisons about daily school life, to recreation opportunities at school, to feel safe at school, and to a healthy school environment. Although the major focus of the study is on how young people describe their experiences at school, the study also examines staff views about young people's rights and what difficulties get in the way of providing for these rights. The survey's findings on participation rights were reported in Marsden Update last December. Now researchers are examining the most critical issue, that of safety.
The open-ended question on attitudes to gay/lesbian/bisexual students showed that these students are very reluctant to reveal their sexual identity for fear of harassment. One female respondent explains, "If they felt safe everyone would know they were lesbian or bisexual, but if they are it must be kept quiet because I don't know of any." And a female staff member said, "I doubt if there are any students who would make themselves known as lesbian. I say this because of the comments (made by students) which are frequently heard denigrating lesbians."
Dr Nairn notes that, "Generally, girls and Maori and Pacific Island students showed more tolerant attitudes. And, as one might expect, it is more difficult to be gay in a boys' school or a rural school, where attitudes tend to be more conservative."
There are hopeful signs that schools are being more proactive in "making schools safe for people of every sexuality", the title and aim of a set of guidelines recently issued by the Post Primary Teachers' Association. Although attitudes and practices among schools, even neighbouring ones, could differ greatly, there were instances of assertive school-wide initiatives and individual support for students. Inevitably, staff, more so than students, perceived that there were mechanisms for protection, support and acceptance of lesbian, gay and bisexual students.
The survey was phase 1 of the Marsden-funded project. Phase 2, which is almost complete, is an in-depth case study of four schools. The results of the research will form a base from which New Zealand's progress under the terms of the United Nations Convention on the Rights of the Child can be evaluated.
For further information, contact Dr Karen Nairn, Children's Issues Centre, P. O. Box 56, Dunedin Tel: (03) 479 5089 Email: karen.nairn@stonebow.otago.ac.nz
Marsden Update is published quarterly by the Marsden Fund and is available free on request. Editor: Glenda Lewis Email: glenda.lewis@rsnz.org