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Canberra, Australia

CSIRO PUBLISHING is an Australian-based science and technology publisher. CSIRO PUBLISHING is the publishing branch of the Commonwealth Scientific and Industrial Research Organisation. They cover a range of scientific disciplines including agriculture, chemistry, plant and animal science, natural history and environmental management. They publish research journals, books, magazines and email newsletters. They also produce videos and multimedia content for students and training. Wikipedia.

Robson B.J.,CSIRO
Environmental Modelling and Software | Year: 2014

This systematic review considers how water quality and aquatic ecology models represent the phosphorus cycle. Although the focus is on phosphorus, many of the observations and discussion points here relate to aquatic ecosystem models in general. The review considers how models compare across domains of application, the degree to which current models are fit for purpose, how to choose between multiple alternative formulations, and how models might be improved. Lake and marine models have been gradually increasing in complexity, with increasing emphasis on inorganic processes and ecosystems. River models have remained simpler, but have been more rigorously assessed. Processes important in less eutrophic systems have often been neglected: these include the biogeochemistry of organic phosphorus, transformations associated with fluxes through soils and sediments, transfer rate-limited phosphorus uptake, and responses of plants to pulsed nutrient inputs. Arguments for and against increasing model complexity, physical and physiological realism are reviewed. © 2014 The Author. Source

Barnard A.S.,CSIRO
Accounts of Chemical Research | Year: 2012

Under a given set of conditions, nanomaterials can crystallize into structures that are entirely inconsistent with the bulk material and may adopt a range of faceted morphologies that depend on the particle size. A size-dependent phase diagram, a graphical representation of the chemical equilibrium, offers a convenient way to describe this relationship among the size, morphology, and thermodynamic environment. Although creating such a diagram from conventional experiments is extremely challenging (and costly), theory and simulation allow us to use virtual experiments to control the temperature, pressure, size, structure and composition independently.Although the stability and morphology of gold nanoparticles has been add-ressed numerous times in recent years, a critical examination of the literature reveals a number of glaring contradictions. Typically gold nanoparticles present as multiply-twinned structures, such as icosahedra and decahedra, or faceted monocrystalline (fcc) shapes, such as truncated octahedra and cuboctahedra. All of these shapes are dominated by various fractions of {111} and {100} facets, which have different surface atom densities, electronic structure, bonding, chemical reactivities, and thermodynamic properties. Although many of the computational (and theoretical) studies agree on the energetic order of the different motifs and shapes, they do not necessarily agree with experimental observations. When discrepancies arise between experimental observations and thermodynamic modeling, they are often attributed to kinetics. But only recently could researchers analytically compare the kinetics and thermodynamics of faceted nanoparticles.In this Account, we follow a theoretical study of the size, shape, and structure of nanogold. We systematically explore why certain shapes are expected at different sizes and (more importantly) why others are actually observed. Icosahedra are only thermodynamically preferred at small sizes, but we find that they are the most frequently observed structures at larger sizes because they are kinetically stable (and coarsen more rapidly). In contrast, although the phase diagram correctly predicts that other motifs will emerge at larger sizes, it overestimates the frequency of those observations. These results suggest either a competition or collaboration between the kinetic and thermodynamic influences.We can understand this interaction between influences if we consider the change in shape and the change in size over time. We then use the outputs of the kinetic model as inputs for the thermodynamic model to plot the thermodynamic stability as a function of time. This comparison confirms that decahedra emerge through a combination of kinetics and thermodynamics, and that the fcc shapes are repressed due to an energetic penalty associated with the significant departure from the thermodynamically preferred shape. The infrequent observation of the fcc structures is governed by thermodynamics alone. © Published 2012 by the American Chemical Society. Source

Barnard A.S.,CSIRO
Reports on Progress in Physics | Year: 2010

As we learn more about the physics, chemistry and engineering of materials at the nanoscale, we find that the development of a complete understanding is not (in general) possible using one technique alone. Computer simulations provide a very valuable addition to our scientific repertoire, but it is not immediately intuitive which of the many methods available are right for a given problem. In this paper, various computational approaches are described as they apply to the study of the structure and formation of discrete inorganic nanoparticles. To illustrate how these methods are best used, results of studies from many research groups are reviewed, and informal case studies are constructed on carbon, titania and gold nanoparticles. © 2010 IOP Publishing Ltd. Source

Recognition that climate change could have negative consequences for agricultural production has generated a desire to build resilience into agricultural systems. One rational and cost-effective method may be the implementation of increased agricultural crop diversification. Crop diversification can improve resilience in a variety of ways: by engendering a greater ability to suppress pest outbreaks and dampen pathogen transmission, which may worsen under future climate scenarios, as well as by buffering crop production from the effects of greater climate variability and extreme events. Such benefits point toward the obvious value of adopting crop diversification to improve resilience, yet adoption has been slow. Economic incentives encouraging production of a select few crops, the push for biotechnology strategies, and the belief that monocultures are more productive than diversified systems have been hindrances in promoting this strategy. However, crop diversification can be implemented in a variety of forms and at a variety of scales, allowing farmers to choose a strategy that both increases resilience and provides economic benefits. © 2011 by American Institute of Biological Sciences. All rights reserved. Source

Dodds P.N.,CSIRO | Rathjen J.P.,Australian National University
Nature Reviews Genetics | Year: 2010

Plants are engaged in a continuous co-evolutionary struggle for dominance with their pathogens. The outcomes of these interactions are of particular importance to human activities, as they can have dramatic effects on agricultural systems. The recent convergence of molecular studies of plant immunity and pathogen infection strategies is revealing an integrated picture of the plant pathogen interaction from the perspective of both organisms. Plants have an amazing capacity to recognize pathogens through strategies involving both conserved and variable pathogen elicitors, and pathogens manipulate the defence response through secretion of virulence effector molecules. These insights suggest novel biotechnological approaches to crop protection. © 2010 Macmillan Publishers Limited. All rights reserved. Source

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