Search Rutherford Discovery Fellowship awards 2010–2017

Public Summary: The remarkable optical properties of nanostructures are increasingly used in a variety of emerging optical methods aiming at dramatically improving the sensitivity of devices for molecule detection and identification, ultimately down to a single-molecule. Potential applications are varied and far-reaching: quality control in the industry, drugs roadside detection, biochemical and forensic analysis, or ultra-fast DNA sequencing. Among these methods, surface-enhanced Raman spectroscopy and surface-enhanced fluorescence are currently those showing the most promises, in part due to the established widespread use of their conventional counterparts, Raman and fluorescence spectroscopy, in both fundamental research and applications. This research project aims at investigating a number of outstanding issues in both the fundamental understanding of these techniques and their application to practical problems. These studies will be both theoretical and experimental. This mix of theory and experiment will help to bridge the gap between fundamental studies and applications, which is too often a significant impediment to progress in this field. In parallel to these, some yet unexplored innovative variations of these techniques will be investigated. This work has the potential to dramatically improve our fundamental understanding of single molecule on surfaces and the applicability and transfer of these advanced techniques to real-world problems.

Public Summary: Sparked by the experimental achievement of Bose-Einstein condensation (BEC), a new field of ultra-cold atoms has emerged. A BEC typically consists of millions of neutral atoms at a few billionths of a degree above absolute zero, contained in a vacuum chamber, and levitated in space by magnetic or optical fields. At these ultra-low temperatures, the atoms undergo a phase transition, coalescing into a mesoscopic quantum droplet exhibiting the remarkable property of frictionless flow, known as superfluidity. When a superfluid rotates, it does so by creating a quantized vortex resembling a tiny fluid whirlpool or tornado. Mutually attracted vortices and anti-vortices can pair up into vortex dipoles that carry linear momentum and are central to understanding turbulent flows. The scattering of vortex dipoles, the potential for using focussed sound pulses to create vortex dipoles, and the nature of forces acting on individual vortices are central questions at the forefront of superfluid physics. Using a newly developed theory of ultra-cold atomic superfluids we will investigate these processes to give fundamental insights into the nature of quantum turbulence and the interface between vortex dynamics and superfluidity.

Public Summary: Global, regional, and local climate and weather models provide vital information to keep our communities safe from weather hazards, maintain high water and energy efficiency for food production and predict our renewable energy resource. These same models are also used to synthesize climate data for ecological and biodiversity studies, and agricultural and engineering meteorology. It is therefore vital to develop reliable and accurate models that give better estimates of surface-atmosphere thermodynamic fluxes, which are essential components for accurate surface wind, temperature and humidity predictions. The dynamics of the lowest 2 kms of Earth’s atmosphere, or the atmospheric boundary-layer, are poorly represented in weather and climate models due to inadequate representation of process such as turbulence, or rapid air fluctuations controlling energy and moisture exchanges at the surface-atmosphere interface. This lack of knowledge is mainly due to the complex and unpredictable nature of atmospheric turbulence and the limitations of our observational systems that hinder a comprehensive dynamic representation of the physical processes, which results in poor model performance. Climate and weather models are merely a numerical “engine” of mathematical formulations reflecting what scientists understand about atmospheric processes. Our current near-surface turbulence observational systems can provide ultra-high temporal sampling resolutions appropriate for turbulent transport analyses, but lack the essential spatial footprint to capture the spatially heterogeneous turbulent flux. It is increasingly evident that near-surface turbulent fluxes are part of a wider spatial spectrum of atmospheric coherent turbulent structures that are not accounted for in our current theoretical formulations. This research programme will address the principles behind surface-atmosphere interactions by critically reassessing the measurement techniques, thereby testing and developing both existing and new theoretical formulations of land-atmosphere turbulent interactions. It is critical to develop a comprehensive approach to investigating coherent turbulence structures that involves tracking their downward propagation towards the surface, and then observing their impacts on surface temperature and velocity fields. Our approach will be based on utilizing state-of-the-art far-infrared cameras employed in field experiments and lab-based physical models to develop a new improved spatial model of surface-atmospheric turbulent interactions. There are two main research objectives to this programme 1) to develop a physical model of a scaled-down landscape chamber to serve as a flexible experimental platform for time sequential thermography and in-situ turbulence measurements. This objective will also address our outstanding questions related to interpreting field-based results, such as how do unique surface properties (like thermal admittance, aerodynamic roughness and soil moisture) affect the brightness temperature turbulent signal measured by the infrared cameras?; 2) to rigorously validate the hypothesis that rapid fluctuations in brightness temperature are an accurate measure of boundary-layer turbulence. This objective will explore a vast library of boundary-layer turbulence measurements through traditional in-situ measurements and new near-target remote sensing via time sequential thermography. The analysis will focus on the extraction of key information from both measurement techniques for validating the spatio-temporal brightness temperature perturbations under a variety of surface types and meteorological regimes.

Public Summary: Matroids are mathematical objects used for understanding the nature of space. Many branches of classical mathematical subjects are dedicated to studying space, but these classical tools are for use in continuous space; space that contains an infinite number of points. The mathematics underlying computer science is not continuous and infinite. Instead it is discrete and finite. Matroids are the tools we must use if we wish to understand space from a finite, discrete, point of view. Therefore we can think of matroid theory as being computer-age geometry. Model theory is the mathematical study of formal languages, and the structures they make statements about. In model theory, we ask what properties of mathematical structures can be expressed using sentences from a specified formal language. Although model theory has been extensively used in many areas of discrete mathematics, there are essentially no results in matroid theory that exploit model-theoretical techniques. The central aim of this project is to correct that omission.

Public Summary: Nanofluidics, the study and application of fluid flow in and around nanoscale structures, is a highly topical field, inspired by microfluidics, nanoscience and biotechnology. Developments in this area can impact a tremendous range of research: from cellular ion channels to sands and soils, from single molecules to colloidal suspensions, from fundamental physics to device engineering. Nanofluidics is likely to be most useful, and become most familiar, in medical technologies. Future diagnostics and detectors will be miniaturised, all-in-one tools suitable for use in the home or at the point of care. Medical technologies are a fast-growing export earner, with potential to contribute strongly to New Zealand's push for science-led prosperity over the next decade and beyond.
At present, the range of tools available to the nanofluidic 'plumber' is limited - microfluidic devices are commonplace, but the next steps towards the nanoscale naturally meet technological roadblocks. The most prominent roadblock concerns transport of fluid, and of particles within the fluid - via pressure, electromagnetism or Brownian motion, for example. Transport mechanisms can interact in a complicated way, restricting our ability to practically exploit them. It is no surprise that transport which depends on electronic surface charge is particularly hard to control, because surface effects become relatively important at small scales. In addition to charge on the walls of a channel, there is also charge on particle surfaces, and the distribution and flow of ions must also be considered in an aqueous environment.
This project will use theory and experiments to develop novel tools, harnessing nanofluidic transport for the would-be plumber. Two experimental systems will be central to the specific work carried out. Both are ideal for studying nanofluidic transport, because they allow mechanisms to be controlled and observed at relevant (and even tunable) length scales. The first involves tunable nanopores, a nanotechnology being developed by Christchurch-based startup Izon Science. Tunable nanopores can be used to sense standard polystyrene nanoparticles within an aqueous electrolyte, and to accurately measure their concentration, size and surface charge. Here, we will use these pores to analyse a wide range of particle types, including gold and magnetic nanoparticles, viruses, platelets, and large biomolecules. For the second experimental system, we will draw upon our recent world-first demonstration that small drops can enhance the capillary-driven uptake of liquid into a tube. When compared with uptake from a large reservoir, drop-enhanced uptake proceeds more quickly, and uptake is even possible when the liquid and tube are 'non-wetting' (e.g. water and Teflon). Drop-enhanced uptake could be used to control transport when phase boundaries are present.
Like a plumber's crescent wrench, the tools we hope to develop are very general, and are likely to be useful in the development of many different technologies. Any specific application will probably require collaboration with other parties and dedicated attention to a specific research question. The project plan recognises this by including a specific objective for speedily taking advantage of commercial opportunities as they arise.

Public Summary: The last decade has seen a great expansion in the legal protection of privacy in England, New Zealand and the wider common law world. Change in England was ushered in by the incorporation of the European Convention on Human Rights right to 'respect for private life' into domestic law (via the Human Rights Act 1998). Holding themselves bound to develop common law consistently with Convention principles, courts protected 'private life' by extending the action for breach of confidence to include private (but not strictly confidential) information. Legislation such as the Data Protection Act 1998 and the Protection from Harassment Act 1997 was also passed, enhancing privacy protection still further. Modern English privacy law is therefore a complex product of domestic legislation, common law, and the jurisprudence of the European Court of Human Rights. The book which is the subject of this proposal will analyse these different strands of jurisprudence and, for the first time, pull them together into a coherent theory of privacy law. The book will address four central questions: what is privacy, why is it worthy of protection, how is it currently protected in English law, and what further developments are needed to create a comprehensive, coherent private law privacy right? The book will combine both theoretical and doctrinal analyses and draw on a broad range of sources including scholarly work and case law from Europe, England, New Zealand and other Commonwealth and common law jurisdictions.

Public Summary: The potential for rapid deglaciation of West Antarctica remains a primary uncertainty in the Intergovernmental Panel on Climate Change (IPCC) predictions for 21st Century sea level rise. The recent and unpredicted collapse of multiple ice shelves and rapid acceleration of discharge of Antarctic ice suggests that dynamical responses to warming play a more significant role than is currently understood and captured in coupled climate-ice sheet models. Such models can be improved and validated by replicating known past changes. The Roosevelt Island Climate Evolution (RICE) project is an international partnership seeking to understand past, present, and future changes of the Ross Ice Shelf, a major drainage pathway of the West Antarctic Ice Sheet. About 5 to 3 million years ago, the last time when atmospheric carbon dioxide (CO2) concentration and temperatures were similar to those predicted for the end of the 21st Century, the Ross Ice Shelf disintegrated multiple times, initiating the collapse of West Antarctica. However, no high resolution data exist from this time period. To determine the rate of change, RICE will provide an annually resolved ice core record for the past 20,000 years, when global temperatures increased by 6 deg C to preindustrial temperatures, global sea level rose by ~120 m, and the Ross Ice Shelf grounding line retreated over 1,000 km. Most of the Ross Ice Shelf retreat occurred when global sea level had already reached modern levels. For this reason, the precise correlation between increasing air and ocean temperatures, and the velocity and characteristics of the ice shelf retreat, will enable us to determine accurately the sensitivity of the Ross Ice Shelf to warming. Our results will significantly advance models to improve predictions of the future behaviour of the Ross Ice Shelf, and hence West Antarctica's contribution to sea level rise

Public Summary: The evolution of intelligence is one of nature’s greatest mysteries. We have little idea how we came to be so clever, or even how our minds actually differ from those of other species on our planet. For over 100 years researchers have compared human and animal intelligence in order to gain insight into this area. However, these comparisons have been based on a “success-testing” approach, where researchers simply examine whether an animal can solve a problem or not. This approach has generated a great deal of debate, but little actual progress, because success-testing is flawed. Just because an animal solves a problem, it does not follow that the animal has used the same cognitive mechanisms as humans to do so. I have recently developed a novel “signature-testing” approach to avoid this problem. By searching for the signatures of cognitive mechanisms (their limits, errors and biases) it is possible to show whether a human and an animal truly think in the same way or not. I will combine an experimental procedure I recently invented with this novel theoretical approach to compare the causal reasoning of children to that of two highly intelligent bird species: kea and New Caledonian crows. Causal reasoning is one of the most powerful types of thought that humans possess. It allows us to form hypotheses about phenomena without obvious causes, such as lightning and disease, and so is at the heart of our ability to think scientifically. By mapping the causal reasoning of children, I will identify the limits, errors and biases that characterise children’s scientific thought. Searching for these signatures in New Caledonian crows and kea will show which aspects of this cognition are shared, and which are different, between my three study species. The pattern of cognitive signatures found will show if humans and the tool-making New Caledonia crow have enhanced causal reasoning abilities compared to those of the non-tool making kea. Thus I will uncover whether tool behaviours really are a key driver of the evolution of intelligence, and so shed light on one of the biggest questions in psychology: how intelligence actually evolves.

Public Summary: Awareness of motor neuron disease (MND) is growing, following the hugely successful ice-bucket challenge and the release of the Stephen Hawking biopic “The Theory of Everything” in 2014. But we are poised on a precipice; increased awareness and research funding must yet be translated into understanding of disease mechanisms before patients can benefit from better treatments. Indeed, the typical sufferer of MND will die from the disease within 3 years, meaning that Hawking currently represents the exception, rather than the rule. MND is a fatal and incurable movement disorder affecting ~1 in 15,000 New Zealanders. In this disease, motor neurons within the brain and spinal cord degenerate, causing progressive loss of movement function. Both genetic and environmental factors contribute to motor neuron death in MND. But do these factors also affect other types of brain cells? I have exciting new evidence to suggest that they do. Pericyte cells, which surround the blood vessels in the brain and form part of the blood-brain-barrier, are also damaged in MND. This may explain how blood-borne irritants can leak into the brain in MND, which worsens the plight of the motor neurons. This work will use pericyte cells grown directly from the brain and spinal cord of MND patients who have bequeathed these tissues to our Human Brain Bank. This incredible resource will allow us to conduct two important studies. The first study asks whether pericytes from brain regions containing dying motor neurons show the same disease signatures as pericytes from brain regions which are spared in MND. The second study then tests a range of chemical compounds for their ability to provoke or alleviate a disease signature in pericytes. Together these studies will determine whether the disease processes occurring within motor neurons also occur independently within pericytes. This work has important implications for identifying new treatments for disease- by helping us to identify all of the cell types an effective treatment for MND must target, as well as allowing us to test potential new treatments using cells other than just motor neurons. By exploring the role of non-neuronal cell types such as pericytes, we hope to better understand why MND develops and how we can best treat it. And perhaps one day soon we will have our “Theory of Everything” regarding this devastating disease.

Public Summary: Forests play a vital role in carbon and water cycles locally, regionally and globally. New Zealand forests are unique ecosystems with very high proportions of endemic plant and animal species and they also support a thriving tourism industry. Despite the importance of forests, there has been only limited research on climate change impacts on our native terrestrial ecosystems. In much of New Zealand, climate change will result in longer, drier summers, more frequent extreme events such as droughts, rising temperatures and associated increased concentrations of atmospheric carbon dioxide. Alterations to rainfall patterns affect water-use and productivity of plants across the world and NZ plants may be particularly vulnerable to periods of low moisture availability. Our vegetation evolved under moist conditions so many species are not well-prepared for drought. Kauri (Agathis australis) is a key tree species in Northland forests. Kauri trees are culturally significant, store huge amounts of biomass and play a central role in species assemblage patterns in forests. Yet kauri have physiological traits that make them unfit for drought conditions. Drought-induced forest mortality is a global phenomenon but recent research is suggesting that trees in moister parts of the world are more likely to succumb to drought than those areas with less annual rainfall. Trees can die in different ways during drought because there are several metabolic and hydraulic failure points that can be triggered during dry conditions and warmer temperatures. Responses of each tree depend on physiological adaptations, site conditions and other factors such as pathogen attack. The vulnerability and mechanisms of drought mortality in New Zealand trees have not been studied so the critical minimum water requirements of different species are unknown. This is an added pressure for kauri on top of the threat of kauri dieback caused by the water mould, Phytophthora taxon Agathis. I will create artificial drought in forest plots by diverting rainfall before it reaches the forest floor. There will be three treatment plots to simulate spring drought, summer drought and reduced rainfall throughout the year as well as a control plot. I will measure plant physiological responses of several tree species to these drought treatments and work with colleagues to study the consequences of drought for soil microbial communities, soil carbon storage, tree ferns, epiphytes, ecosystem productivity and composition and longer term impacts though analysis of tree rings. By using an integrated approach, this ground-breaking research will capture a range of ecosystem responses that would be missed if each component was studied in isolation. The five-year time frame of the Rutherford Discovery Fellowship scheme allows for assessment of subsequent droughts and longer-term impacts of dry conditions. The information gathered is urgently needed for effective management and conservation of our native forests under a changing climate.