Search Rutherford Discovery Fellowship awards 2010–2017

Public Summary: Many organic molecules and polymers have an electronic structure similar to inorganic semiconductors like silicon. Semiconductors provide for the absorption of energy when electrons are energized to form electronic excited states. The electronic excited states of organic semiconductors can be exploited in technologies like solar cells, light-emitting diode displays, and lasers. Motivated by promise of abundant clean energy at low-cost, organic solar cells have achieved encouraging efficiencies of close to 8% to date - spurring chemists to develop new materials that strongly absorb sunlight and generate photocurrent. Yet understanding the physics of photocurrent generation sufficiently to guide the design of improved materials has proven to be a formidable challenge. The crux is that excited state energy is dissipated extremely quickly, meaning that key processes are hidden in timescales that require special tools to measure. This research program will develop and exploit advanced laser spectroscopy tools to address this problem. Sequences of extremely short laser pulses will be used to generate excited states in organic solar cells and probe the pathways through which energy is relayed between different parts of the cell. Amongst the technical challenges are i) the ability to see on an enormous range of timescales spanning seconds down to femtoseconds (millionths of billionths of seconds), and ii) the ability to identify short-lived excited states that are nearly invisible. The proposed research program uses a combination of extremely sensitive custom-made ultrafast optical absorption and emission spectroscopy techniques capable of tracking the fate of the absorbed photon energy. With the ability to see different types of short-lived excited states, this research program draws inspiration from natural photosynthesis to advance new design paradigms in artificially engineered solar energy conversion. This research program could provide a route to low-cost solar cells and will enhance our understanding of a range of other photoactive devices.

Public Summary: Though the first diagram of a food web---the network of who eats whom in an ecosystem---was published in the late 1800s, the past decades in particular have seen tremendous growth in the data available to characterise empirical interaction networks. Studies of these webs have helped unravel the ecological determinants of community structure, as well as established an unambiguous link between species-species interactions and the resplendent biodiversity observed in natural ecosystems. As a result of these studies, it is easy to conclude that the community-scale consequences of species' interactions have never been clearer; and yet the ecological and evolutionary implications for populations of individual species remain a mystery. Moreover, because we have been studying present-day networks through an ecological lens, we do not understand the interplay between speciation, extinction, and adaptation and a community's ability to maintain its biodiversity, species composition, or the structure of the interactions between species. The overall objective of my proposed research is therefore to bridge this gap and to build toward a general theory of evolution in ecological networks. The business magnate Warren Buffett once said that 'Wide diversification is only required when investors do not understand what they are doing.' Buffett's primary interests are clearly not in ecology; there are, however, strong parallels between what it takes to maintain either a functional financial sector or a persistent ecological community. Unfortunately, while economics seeks to rigorously outline the costs and benefits of entering a market, we still do not know what trade-offs are experienced by a species as a result of forming part of a larger, more complex community. Without quantifying the evolutionary component of who actually 'benefits' in ecological networks---the individuals, the species, or the community---we will continue to be limited in our understanding of the structure, function, and future of ecological communities.

Public Summary: 'Is there life elsewhere in the Universe?' This question has puzzled mankind for centuries. In the last twenty years we have made enormous strides towards answering it with the discovery of planets orbiting stars other than our own Sun. To date, over 700 extra-solar planets have been discovered. Many of these planets are very different to those planets in our Solar System, being typically large gas giant planets orbiting close to their host star. As techniques and facilities improved over the years, planetary systems more like our own have been found, with smaller, rocky planets orbiting their host star at distances similar to that of our Earth around the Sun. We will soon be discovering planets very similar to Earth.
How planets form around stars is still uncertain, with at least two competing theories. Deciding which theory is correct will require an estimate of how many planets there are and what masses they have. No single method to date is capable of finding every type of planetary system and so to get a proper understanding of how many planets exist in the Universe, we need to use a variety of complementary methods to detect planets.
The technique that I use to detect extra-solar planets relies on the way gravity deflects light - a prediction according to Einstein's General Theory of Relativity. The technique - called gravitational microlensing - allows the detection of small, earth-mass planets orbiting their host stars at orbital radii similar to the Earth-Sun distance. The Microlensing Observations in Astrophysics (MOA) collaboration looks for these tiny signals arising from distant planets, using a dedicated 1.8 metre telescope observing from the South Island of New Zealand. These observations are combined with observations made with telescopes situated around the world and the data are searched for evidence of planets.
MOA has led the world in this field of research, being one of the first survey operations of its kind in the world. The MOA collaboration has defined the modern approach to detecting extra-solar planets via microlensing and many similar survey projects are following in MOA's steps. Microlensing observations may also be performed using a space telescope. Space telescopes such as WFIRST, from NASA and EUCLID, from the ESA, will be suitable for making microlensing observations. I will continue to promote the detection of extra-solar planets using these and other space telescopes.
The increase in data from these new projects will need to be analysed - a task not possible by the relatively small number of experts worldwide who are capable of this work. An automated analysis system is required to cope with the difficult job of detecting and characterising any planetary signal in the wealth of data that soon will be coming from all the new surveys. I, as a Rutherford Discovery Fellow, will design and create this automated analysis system and ensure New Zealand retains its leading position in extra-solar planet discovery.

Public Summary: The human genome harbours evidence of long-term and repeated exposure to retroviral pathogens. Consequently, cells have developed an array of proteins as part of the innate immune response to recognise, prevent and contain infection by retroviruses. Termed restriction factors these proteins disrupt multiple stages of the retroviral lifecycle including reverse transcription, viral assembly, genome replication and viral release. Members of the tripartite motif (TRIM) protein family have been identified to have a crucial role in this vital cellular immune response to retroviral pathogens. The TRIM protein family is characterised by a conserved domain architecture, called the RBCC motif. While little is known about the processes and mechanism of retroviral restriction, the interactions made by this motif govern TRIM protein function and the ability of TRIM proteins to both recognise retroviral components within the cell and disrupt the retroviral lifecycle. These interactions include the formation of multimers and higher order assemblies, interactions with cellular machinery and the recognition of retroviral components. Structural biology has the ability to examine these interactions at atomic resolution allowing a detailed analysis of the mechanism and determinants of restriction. Investigation of this vital aspect of cellular immunity may lead to vital new opportunities to block, and clear retroviral infections including HIV, the causative agent of AIDS.

Public Summary: The electromagnetic output of the sun defines our physiology. Human vision is tuned to the visible spectrum, infrared radiation provides life-giving warmth, while ultraviolet light has a contradictory nature that is not fully understood. Ultraviolet radiation attacks the upper layers of our skin through collagen and DNA damage causing premature skin aging and melanoma, while at the same time providing our primary means of vitamin D synthesis. The importance of vitamin D to our general well being has only recently been fully recognised with vitamin D deficiency being linked to increased risks of multiple sclerosis, osteoporosis, diabetes, bowel cancer, and heart disease. The ultraviolet climate in New Zealand is complex and impacts us in subtlely different ways - for Maori and Pacific Islanders the risk of vitamin D deficiency is significantly increased while those of European origin have the highest per capita rates of skin cancer in the world. What we share is the need to understand the complex nature of the relationship between our health and solar ultraviolet radiation. From a technological point of view, the ultraviolet spectrum is the next stop for faster data storage and communications technologies that have already evolved from red to blue laser light. Understanding and harnessing the ultraviolet spectrum from health and technology perspectives requires new semiconductor materials such as zinc oxide and the oxides of gallium, indium, tin, and magnesium. These metal oxide semiconductors represent a new frontier for material science, possessing fascinating properties such as unusual surface electron layers, strong internal electric fields, and the rare combination of high mobility conduction and transparency that is much sought after for applications such as optical displays, smart windows, electronic paper and transparent electrodes for wide-area solar cells.
This research program is designed to explore the growth, behaviour, and applications of metal oxide semiconductors with bandgaps (responsivity) in the ultraviolet spectrum. It provides for a comprehensive investigation of their unusual physical properties and the development of new optoelectronic devices with a particular focus on delivering new epidemiological tools to help provide answers to key health questions concerning the risks and benefits of ultraviolet radiation to human health. It is also designed to transfer significant new research and technology capability by working closely with key overseas collaborators on advanced material characterisation techniques not available in New Zealand.

Public Summary: The reconstruction of paleoenvironmental conditions is vital for assessing ongoing climate change and societal vulnerability with regard to both extreme events and long-term climate reorganization. Speleothems (cave carbonate deposits) provide some of the best terrestrial archives of past environmental conditions, yet the existing state of knowledge remains hampered by the complexity of speleothem isotopic records. Consequently, stable isotope-based palaeoclimate reconstructions from speleothems remain essentially qualitative, with many workers questioning the meaning of records with even strong hydrological forcing (where hydro-climatological factors exert the greatest signal variance in palaeo proxies), such as those found in Chinese monsoonal speleothems. Speleothem science has made outstanding contributions to understanding past global climate change using only a handful of mainly geochemical proxies linked to regional climate conditions. Unfortunately, traditional proxies extracted from cave carbonates (e.g. oxygen and carbon isotope ratios) seldom allow quantitative estimates with regard to rainfall amount, infiltration or temperature because they record multiple forcings. Recent technological advances provide new quantitative tracers and analytical tools, including magnetic analysis, fluid inclusion isotope signatures, and nonlinear data analysis. Some of these methods have already become “routine”, while others have not yet been used in speleothem research. In this project, I will develop new chemical and physical environmental proxies to study changes in the important climate parameters of rainfall and temperature. These proxies will allow the forcing factors that influence traditional but ambiguous tracers to be distinguished from each other, and quantitative climate reconstructions to be developed. The project combines geochemical, magnetic and statistical approaches, allowing the proxies to be verified quickly and enabling swift development of quantitative models. In particular, the Rutherford Discovery Fellowship will enable me to develop a new proxy of drip-point discharge based on particle-transported trace metals which will form the foundation of efforts across the QUEST project (see leadership section and CV), and will underpin the separation of climatic drivers in isotope records. Particles in cave waters have the potential to encode a range of important information relating to hydrology (trace metals, magnetism) and surface temperature (soil-derived organics). I will verify the aforementioned proxy for drip-point discharge, which would be the first truly quantitative measure of hydrological variability in the past and which therefore holds enormous significance for our understanding of past climatic change. This proxy utilises trace metals (which originate from metal-organic complexes in dripwaters) as chronometers of drip-point hydrology. The robustness of this tracer will be strengthened by combining it with magnetic data, which quantifies infiltration dynamics. Chemical and statistical analyses will be used to construct the first robust method for disentangling hydrological and temperature signals in speleothem isotope records. These novel proxies will be tested using Australasian speleothems, producing new and detailed records of the El Niño–Southern Oscillation variability and the Southern Annular Mode over the last 10,000 years, thereby expanding our understanding of Southern Hemisphere climate systems.

Public Summary: New Zealand has the 4th largest exclusive economic zone in the world. We depend on the economic and environmental value of this marine estate, through fisheries, shipping activities, energy and mineral exploration, tourism and recreational use. All these activities generate significant noise alongside the natural sounds produced by the animals; making the ocean an increasingly noisy place. This myriad of sounds can travel large distances in all directions due to the excellent transmission of sound in water. Of major concern is that manmade sources have doubled the level of ambient background noise of the worlds oceans. A way to monitor these activities is passive acoustics i.e. listening to the sea. Not only can passive acoustics be used to monitor man-made sources, but research has shown that it can be used to monitor the natural marine environment, with reefs separated by a few kilometres having significantly different sound signatures. Therefore, passive acoustics can be used to monitor human and biological activities and their interactions. In some ways, this is analogous to remote sensing from space which has generated huge progress in our understanding of terrestrial systems and the sea-surface. However, space-based remote sensing cannot characterise the water column below the ocean surface whereas acoustics has that potential. The general goal of this research is to understand the acoustic ecology of the pelagic environment, as a contribution to understanding, monitoring and management of coastal marine environments. The proposed research specifically tests the proposition that passive acoustics can provide an efficient cost-effective mechanism for monitoring ecosystem health.

Public Summary: Fault zone rocks, particularly those that delineate tectonic plate boundaries, have distinct structural fabrics and mineralogy that give them unique mechanical properties, such as low and anisotropic permeability, and slip-weakening behaviour. They form through multiple overprinting cycles of shearing, and alteration by fluid-rock interactions. The unique mechanical properties mean fault rocks influence movement of fluids within the Earth, affecting geothermal circulation and mineral deposition. They also cause tectonically-driven deformation to localise on the structures, allowing them to accommodate earthquake-generating slip, and facilitating operation of the Earth's plate tectonic system. Finally, they result in unique geophysical signatures that are extensively employed in mineral exploration targeting. Fault and ductile shear zone rocks can be revealed at Earth's surface due to uplift; this is the case in New Zealand's Alpine Fault zone, where exposed rocks are frozen equivalents of those presently deforming at depths of up to 35km. Drilling into active faults such as this, and collecting samples from the drilled hole(s) provides a third dimension in pressure-temperature-time (all of which affect mechanical behaviour). New (electron microscopic) methods allow targeted observation of the very fine structure of recovered materials. Deformation processes can also be simulated and geophysical properties measured in innovative high pressure-temperature rock deformation apparatuses, and by computational modeling. All these methods will be drawn on to unravel the complex processes that result in formation and evolution of unique fault zone rocks as they are sheared. The program will both take advantage of New Zealand’s location astride a tectonic plate boundary, and inform New Zealand’s societal understanding of the hazard this situation presents. It will benefit from contributions of an extensive international network of collaborators that work with the Principal Investigator (PI). Furthermore, Postgraduate Students and Postdoctoral Scholars, many already engaged in preliminary research, will contribute to the success of the program thus building capability and establishing New Zealand as a leader in the field of fault zone research. It will allow the PI to motivate, mentor and educate the next generation of New Zealanders on their way to becoming internationally respected scientists. The PI is recognized as an effective organiser and motivator of team research in New Zealand and internationally. Co-ordinating and interacting with multinational teams requires her to juggle support from multiple platforms. This Fellowship will allow her to lead her own innovative world-class research program under one stable umbrella so that her scientific foci emerge from the consortia environments, and provide opportunities for leadership growth in other areas.

Public Summary: After the horrors of World War Two, New Zealand played a leading role in the development of international human rights laws and norms. With a strong tradition of giving everyone 'a fair go', New Zealanders were keen to establish legal and structural safeguards to protect those most vulnerable at home and abroad. Through the 1970s and 1980s, in particular, New Zealand proudly introduced human rights norms into domestic law and policy, and developed new institutions like the Human Rights Commission to provide oversight and education. This approach culminated with the introduction of the Bill of Rights Act in 1990 (BORA), which embedded international civil and political rights into New Zealand's legal framework. Yet, recent evidence shows that human rights are in decline in New Zealand. Many previous human rights standards have deteriorated, new laws frequently conflict with the rights contained in BORA, legal commentators detail that human rights cases are almost impossible to win, and human rights are often negatively represented within governmental and media discourse. This leads to a question: what happened to human rights? Drawing upon a qualitative multi-method approach that employs extensive documentary analysis as well as interviews and focus groups, this project considers the status of human rights in New Zealand. It examines the factors that have turned New Zealand's approach from one in which human rights were optimistically implemented and enhanced to a stance that is more pessimistic, where human rights are discursively and practically undermined. The research will specifically address these concerns in relation to three populations that are linked to weakened human rights practices: children in trouble with authorities, prisoners and asylum seekers/refugees. It considers the contexts in which their rights have been both observed and curtailed from the end of World War Two to the present day. In doing so, it will examine the role of official and public discourse in providing legitimacy and support for human rights action and negation. The project will also chart the contemporary challenge to human rights erosion, and explain the ways in which New Zealanders and international actors continue to affirm human rights for the three groups in this study. The research will, finally, explore how the culture of human rights can be reinvigorated in New Zealand, and explain why this move is important to New Zealand society, both locally and globally. This research will lead to new knowledge about changes in human rights thinking, action and culture. The principal investigator will produce a number of academic outputs, including an original monograph on the factors that have enhanced or impeded human rights in New Zealand and an edited book on how human rights cultures can be developed. The project will provide professional opportunities for emerging criminology scholars and will also be 'community conscious', as the principal investigator will actively disseminate new findings to the New Zealand public, civil society organizations, academia and government.

Public Summary: Scientists have long recognized the importance of microbes, which form the basis of all food webs and drive biogeochemical cycles, which recycle key elements such as carbon and nitrogen. Given that the oceans account for more than 90% of the Earth’s biosphere (i.e., the biological component of earth systems) - it is hardly surprising that marine microorganisms account for a large part of the total biomass of life on Earth. These tiny powerhouses produce more than half of the entire global oxygen supply and, in doing so, use up a large proportion of human-generated CO2, a greenhouse gas that is accelerating global warming. Right now, one of the most pressing global science issues is understanding how anthropogenic emissions of greenhouse gases lead to climate change and predicting of how such changes will affect natural and human-influenced ecosystems we rely on (e.g. water quality and fishing). The oceans play a major role in the carbon cycle thanks to the chemical buffering capacity of the carbonate system and to the biological assimilation of CO2 during photosynthesis of phytoplankton (which accounts for 50% of Earth’s photosynthesis). Around 50% of the organic carbon produced by phytoplankton is channelled through microbial consumers (e.g. bacterioplankton) to higher trophic levels or respired back into the atmosphere as CO2. To understand how marine ecosystems will respond to climate change we must first understand the mechanisms by which marine microbes work. The majority of the research done in this field has been conducted in areas of the ocean considered ‘normal’, where primary production is not limited by trace metal availability (trace metals are required to form many important enzymes), and where the production of organic matter is enough to support the consumption of consumers. However, around 30% of the surface ocean lack trace metals inhibiting primary production (these areas are called High Nutrient Low Chlorophyll, HNLC, regions), where the present paradigm of production of organic matter by phytoplankton does not seem enough to account for the consumption rates of microbial consumers. The question then is how do consumers are able to thrive in these HNLC environments. We hypothesise that microbes in these regions might use alternative pathways for carbon and energy adquisition. Recent research carried out in our research group has revealed that the Subtropical Frontal Zone, located at our doorstep off the South Island of NZ, provides ideal model system to study the functional strategies of marine microbes in HNLC regions compared to ‘normal’ regions, results that can help prove that microbial carbon fluxes are different in these neglected HNLC regions of the ocean. Building on preliminary findings, we will combine cutting-edge genomics techniques with experimentation to reveal the unique properties that enable marine microbes to thrive in HNLC environments and which microbes are the main drivers of these processes. By identifying the microbial mechanisms of action and their influence we will be able to understand the role of these magnificent marine microbes and better constrain the effect of climate change and human actions on the marine ecosystems.