56 research outputs found

    Real options for adaptive decisions in primary industries

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    Abstract The long term sustainability of Australian crop and livestock farms is threatened with climate change and climate variability. In response, farmers may decide to (1) adjust practices and technologies, (2) change production systems, or (3) transform their industries, for example, by relocating to new geographical areas. Adjustments to existing practices are easy to make relative to changes to production systems or transformations of an industry. Switching between production regimes requires new investments and infrastructure and can leave assets stranded. These changes can be partially or wholly irreversible but hysteresis effects can make switching difficult and mistakes costly to reverse. ‘Real options’ is a framework to structure thinking and analysis of these difficult choices. Previous work has demonstrated how real options can be applied to adaptation, and extends traditional economic analyses of agricultural investment decisions based on net present values to better represent the uncertainty and risks of climate change. This project uses transects across space as analogues for future climate scenarios. We simulate yields from climate data and draw on data from actual farms to estimate a real options model referred to as ‘Real Options for Adaptive Decisions’ (ROADs). We present results for the transformation of wheat dominant cropping systems in South Australia, New South Wales, and Western Australia. We find that farmers’ decisions, as much as a changing climate, determine how agriculture will be transformed. Please cite this report as: Hertzler, G, Sanderson, T, Capon, T, Hayman, P, Kingwell, R, McClintock, A, Crean, J, Randall, A 2013 Will primary producers continue to adjust practices and technologies, change production systems or transform their industry – an application of real options,  National Climate Change Adaptation Research Facility, Gold Coast, pp. 93. The long term sustainability of Australian crop and livestock farms is threatened with climate change and climate variability. In response, farmers may decide to (1) adjust practices and technologies, (2) change production systems, or (3) transform their industries, for example, by relocating to new geographical areas. Adjustments to existing practices are easy to make relative to changes to production systems or transformations of an industry. Switching between production regimes requires new investments and infrastructure and can leave assets stranded. These changes can be partially or wholly irreversible but hysteresis effects can make switching difficult and mistakes costly to reverse. ‘Real options’ is a framework to structure thinking and analysis of these difficult choices. Previous work has demonstrated how real options can be applied to adaptation, and extends traditional economic analyses of agricultural investment decisions based on net present values to better represent the uncertainty and risks of climate change. This project uses transects across space as analogues for future climate scenarios. We simulate yields from climate data and draw on data from actual farms to estimate a real options model referred to as ‘Real Options for Adaptive Decisions’ (ROADs). We present results for the transformation of wheat dominant cropping systems in South Australia, New South Wales, and Western Australia. We find that farmers’ decisions, as much as a changing climate, determine how agriculture will be transformed

    Formation Flying and Change Detection for the UNSW Canberra Space ‘M2’ Low Earth Orbit Formation Flying CubeSat Mission

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    The University of New South Wales, Canberra (UNSW Canberra) embarked on an ambitious CubeSatellite research, development, and education program in 2017 through funding provided by the Royal Australian Air Force (RAAF). The program consisted of M1 (Mission 1), M2 Pathfinder, and concludes with the formation flying mission M2. M2 is the final mission comprising two 6U CubeSatellites flying in formation using differential aerodynamic drag control. The M2 satellites were launched in a conjoined 12U form factor on RocketLab’s ‘They Go Up So Fast’ launch in March 2021. On 10th September 2021 the spacecraft divided into two 6U CubeSats (M2-A and M2-B) under the action of a small spring force in their near-circular 550km, 45-degree inclination orbit. The formation is controlled by varying the spacecrafts’ attitude, which creates a large variation in the aerodynamic drag force due to the change in the cross-sectional area from the large, double-deployable, solar arrays located on the zenith face of the spacecraft. This paper presents the outcomes of the Formation Flying and Change Detection primary mission objectives for the mission. The results are generated by collecting and analysing optical and RF (Radio Frequency) space domain awareness sensor data from the ground and validating them against GPS (Global Positioning System) and attitude data downlinked from the spacecraft. The outcomes of the broader mission objectives, which include increasing the Technology Readiness Level for a suite of intelligent on-board optical and RF sensor technologies, will be presented in subsequent publications. The results presented here comprise two major campaigns: 1.) The spacecraft separation campaign when the original 12U form factor deployed following launch split in half to form the M2-A and M2-B satellites, and 2) the demonstration of active formation control of the spacecraft via differential aerodynamic drag. M2-A and M2-B underwent several major configuration changes during the spacecraft separation campaign. The results from ground-based sensors detecting the 12U spacecraft separating into two distinct (6U) objects are presented. The effect of the double-deployable solar arrays deployment on the relative orbital motion of the M2-A and M2-B spacecraft is illustrated and compared to data from optical and RF ground-based measurements taken during this window. The formation control campaign involved actively controlling the spacecraft via differential aerodynamic drag in order to significantly alter the separation distance. The mission demonstrated the capability to switch the leading spacecraft’s position between M2-A and M2-B and to actively control separation distance ranging from 130km down to 1km. Formation control is achieved via open-loop, pre-scheduled, commands issued from the UNSW Canberra Space ground station. A two-stage modelling and simulation process is used to derive the scheduled attitude states. Firstly, a batch least squares orbit determination algorithm is applied to GPS data from a steady-state differential drag actuation period (where one spacecraft is in maximum drag and the other in its minimum drag attitude configuration). The batch least squares orbit determination is conducted out using the NASA General Mission Analysis Tool (GMAT), resulting in precise state estimates for each spacecraft and drag coefficient (Cd) estimates for both the maximum and minimum drag configurations. Predictions of trajectory for various attitude profiles can be produced by tailoring the spacecraft’s drag coefficients between the maximum and minimum values generated by the batch least squares state estimation process. Ground-based optical and RF space domain awareness (SDA) sensor measurements collected during the manoeuvre campaign are compared to the spacecraft’s GPS and attitude telemetry data. The SDA sensors are actively seeking to detect changes in the separation distance between the spacecraft. Initial results from an investigation into whether changes observed in photometric light curve signatures can signal the commencement of a differential drag manoeuvre are presented

    The Neural Basis of Following Advice

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    Learning by following explicit advice is fundamental for human cultural evolution, yet the neurobiology of adaptive social learning is largely unknown. Here, we used simulations to analyze the adaptive value of social learning mechanisms, computational modeling of behavioral data to describe cognitive mechanisms involved in social learning, and model-based functional magnetic resonance imaging (fMRI) to identify the neurobiological basis of following advice. One-time advice received before learning had a sustained influence on people's learning processes. This was best explained by social learning mechanisms implementing a more positive evaluation of the outcomes from recommended options. Computer simulations showed that this “outcome-bonus” accumulates more rewards than an alternative mechanism implementing higher initial reward expectation for recommended options. fMRI results revealed a neural outcome-bonus signal in the septal area and the left caudate. This neural signal coded rewards in the absence of advice, and crucially, it signaled greater positive rewards for positive and negative feedback after recommended rather than after non-recommended choices. Hence, our results indicate that following advice is intrinsically rewarding. A positive correlation between the model's outcome-bonus parameter and amygdala activity after positive feedback directly relates the computational model to brain activity. These results advance the understanding of social learning by providing a neurobiological account for adaptive learning from advice

    Multiple Loci Are Associated with White Blood Cell Phenotypes

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    White blood cell (WBC) count is a common clinical measure from complete blood count assays, and it varies widely among healthy individuals. Total WBC count and its constituent subtypes have been shown to be moderately heritable, with the heritability estimates varying across cell types. We studied 19,509 subjects from seven cohorts in a discovery analysis, and 11,823 subjects from ten cohorts for replication analyses, to determine genetic factors influencing variability within the normal hematological range for total WBC count and five WBC subtype measures. Cohort specific data was supplied by the CHARGE, HeamGen, and INGI consortia, as well as independent collaborative studies. We identified and replicated ten associations with total WBC count and five WBC subtypes at seven different genomic loci (total WBC count—6p21 in the HLA region, 17q21 near ORMDL3, and CSF3; neutrophil count—17q21; basophil count- 3p21 near RPN1 and C3orf27; lymphocyte count—6p21, 19p13 at EPS15L1; monocyte count—2q31 at ITGA4, 3q21, 8q24 an intergenic region, 9q31 near EDG2), including three previously reported associations and seven novel associations. To investigate functional relationships among variants contributing to variability in the six WBC traits, we utilized gene expression- and pathways-based analyses. We implemented gene-clustering algorithms to evaluate functional connectivity among implicated loci and showed functional relationships across cell types. Gene expression data from whole blood was utilized to show that significant biological consequences can be extracted from our genome-wide analyses, with effect estimates for significant loci from the meta-analyses being highly corellated with the proximal gene expression. In addition, collaborative efforts between the groups contributing to this study and related studies conducted by the COGENT and RIKEN groups allowed for the examination of effect homogeneity for genome-wide significant associations across populations of diverse ancestral backgrounds

    Resilience and thresholds in river ecosystems

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    This Waterlines report is part of a series of papers commissioned on issues relating to Australian aquatic ecosystems. These Waterlines reports will contribute to improved environmental water management by stimulating discussion, synthesising current thinking, identifying knowledge gaps, and highlighting areas that warrant further investigation. With increasing anthropogenic pressures on river ecosystems, the way that rivers are managed is critical for the maintenance and improvement of human wellbeing. Like much of the world, Australian practices of terrestrial and aquatic ecosystem management have relied on notions of a uniform equilibrium state, where the focus has been on increasing or optimising efficiency and performance in order to deliver defined benefits, including supply or sustainability (Hillman et al. 2005; Walker and Salt 2006). Yet Australian river ecosystems are under pressure and continue to degrade under existing management practices. This is not surprising. Ecosystems are moving targets, which are characterised by episodic change, patchiness, variability, multiple scales of operation, and multiple stable states in both the social and biophysical domains (Gunderson and Holling 2002). Time and time again, ecosystems managed for some type of equilibrium carrying capacity have been thwarted by surprise events, changes in thresholds, and market failures (Carpenter and Folke 2006). Time and time again it has been shown that optimising efficiency to deliver a defined benefit does not lead to sustainability, but rather to collapse (Walker and Salt 2006). New ideas are required to improve the management of Australian river ecosystems. One such idea - resilience thinking - provides an umbrella under which to consider the future management of river ecosystems. Resilience is the amount of change a system can undergo (its capacity to absorb disturbance) and remain within the same regime that essentially retains the same function, structure and feedbacks (Walker and Salt 2006). Resilience thinking seeks to determine how societies, economies and ecosystems can be managed to confer resilience: that is, how to maintain the capacity of a system to absorb disturbance without changing to a different state. The aims of this project are to: 1. review the concepts of resilience and thresholds as they apply in river ecosystems 2. identify the components of a framework to assist planners in managing the resilience of river ecosystems

    The Absolute Stereochemistry of Variabilin and Related Sesterterpene Tetronic Acids

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    The absolute stereochemistry of the marine metabolite variabilin (1). has been suggested by degradation. The absolute stereochemistry of related marine metabolites, ircinin-1 (2), ircinin-2 (3), (8£,13Z,20Z)-strobobilin (4) and (8Z,13£,20Z)-strobobilin (5), have been tentatively established through comparison of their molecular rotations with those for variabilin

    Floodplain ecosystems: resilience, value of ecosystem services and principles for diverting water from floodplains

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    This Waterlines report is part of a series of papers commissioned on issues relating to Australian aquatic ecosystems. These Waterlines reports will contribute to improved environmental water management by stimulating discussion, synthesising current thinking, identifying knowledge gaps, and highlighting areas that warrant further investigation. Australian floodplain ecosystems are a valuable resource. Since European settlement, the character of floodplains has been altered by large-scale developments. The scale of human impacts on floodplain ecosystems has greatly increased in recent times, and deciding how to manage floodplains in terms of land and water allocations is of pressing concern. Negotiating the complex hydrological and ecological trade-offs associated with development is now more challenging because of the uncertainties of climate change and increasing demands for ecosystem services, such as water, food and biofuels (Gordon et al. 2008). As a result, recent policy developments have highlighted the need to improve our understanding of impacts on the hydrological cycle, including the prevalence and severity of nonlinear changes in ecosystems. Decisions on water allocation (encompassing scientific, management-agency and engineering processes that are used together to supply and maintain flows in regulated rivers) for floodplain ecosystems are complex but such decisions can be aided through a consideration of the goods and services provided by floodplains as well as the underlying function of floodplain ecological systems. This project examines the consequences of the dislocation of water from floodplains in terms of the ability of their social–ecological systems to adapt to disturbances, such as floods, droughts and development. An increased understanding of the value of the ecosystem goods and services provided by Australian floodplains will assist managers in making decisions about the trade-offs associated with water diversions. This report identifies some of the major economic values of floodplain ecosystem goods and services in Australia. It explores the contribution of the resilience of ecosystems to the economic value of floodplain ecosystem goods and services and the consequences for the management of water resources and floodplains. It describes some of the limitations and constraints on economic valuation from the perspective of resilience thinking, which describes the complex dynamics of social–ecological systems. General principles are then derived to help guide water allocations for Australian floodplains
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