Linking spatial stock dynamics and economics: Evaluation of indicators and fishery management for the travelling eastern king prawn (Melicertus plebejus)

Reduced economic circumstances havemoved management goals towards higher profit, rather than maximum sustainable yields in several Australian fisheries. The eastern king prawn is one such fishery, for which we have developed new methodology for stock dynamics, calculation of model-based and data-based reference points and management strategy evaluation. The fishery is notable for the northward movement of prawns in eastern Australian waters, from the State jurisdiction of New South Wales to that of Queensland, as they grow to spawning size, so that vessels fishing in the northern deeper waters harvest more large prawns. Bioeconomic fishing data were standardized for calibrating a length-structured spatial operating model. Model simulations identified that reduced boat numbers and fishing effort could improve profitability while retaining viable fishing in each jurisdiction. Simulations also identified catch rate levels that were effective for monitoring in simple within-year effort-control rules. However, favourable performance of catch rate indicators was achieved only when a meaningful upper limit was placed on total allowed fishing effort. Themethods and findings will allow improved measures for monitoring fisheries and inform decision makers on the uncertainty and assumptions affecting economic indicators.

Conducting Gestures : Institutional and Educational Construction of Conductorship in Finland, 1973-1993

Anu Konttinen: Conducting Gestures Institutional and Educational Construction of Conductorship in Finland, 1973-1993. This doctoral thesis concentrates on those Finnish conductors who have participated in Professor Jorma Panula s conducting class at the Sibelius Academy during the years 1973 1993. The starting point was conducting as a myth, and the goal has been to find its practical opposite the practical core of the profession. What has been studied is whether one can theorise and analyse this core, and how. The theoretical goal has been to find out what kind of social construction conductorship is as a historical, sociological and practical phenomenon. In practical terms, this means taking the historical and social concept of a great conductor apart to look for the practical core gestural communication. The most important theoretical tool is the concept of gesture. The idea has been to sketch a theoretical model based on gestural communication between a conductor and an orchestra, and to give one example of the many possible ways of studying the gestures of a conductor.

An exploratory study on the commercialisation of heat pump-fluidised bed drying technology

Fluidised bed-heat pump drying technology offers distinctive advantages over the existing drying technology employed in the Australian food industry. However, as is the case with many other examples of innovations that have had clear relative advantages, the rates of adoption and diffusion of this technology have been very slow. "Why does this happen?" is the theme of this research study that has been undertaken with an objective to analyse a range of issues related to the market acceptance of technological innovations. The research methodology included the development of an integrated conceptual model based on an extensive review of literature in the areas of innovation diffusion, technology transfer and industrial marketing. Three major determinants associated with the market acceptance of innovations were identified as the characteristics of the innovation, adopter information processing capability and the influence of the innovation supplier on the adoption process. This was followed by a study involving more than 30 small and medium enterprises identified as potential adopters of fluidised bed-heat pump drying technology in the Australian food industry. The findings revealed that judgment was the key evaluation strategy employed by potential adopters in the particular industry sector. Further, it was evidenced that the innovations were evaluated against a predetermined criteria covering a range of aspects with emphasis on a selected set of attributes of the innovation. Implication of these findings on the commercialisation of fluidised bed-heat pump drying technology was established, and a series of recommendations was made to the innovation supplier (DPI/FT) enabling it to develop an effective commercialisation strategy.

Evaluation of the Australian branched broomrape (Orobanche ramosa) eradication program

Because weed eradication programs commonly take 10 or more years to complete, there is a need to evaluate progress toward the eradication objective. We present a simple model, based on information that is readily obtainable, that assesses conformity to the delimitation and extirpation criteria for eradication. It is applied to the program currently targeting the annual parasitic weed, branched broomrape, in South Australia. The model consists of delimitation and extirpation (E) measures plotted against each other to form an 'eradograph.' Deviations from the 'ideal' eradograph plot can inform tactical responses, e.g., increases in survey and/or control effort. Infestations progress from the active phase to the monitoring phase when no plants have been detected for at least 12 mo. They revert to the active phase upon further detection of plants. We summarize this process for the invasion as a whole in a state-and-transition model. Using this model we demonstrate that the invasion is unlikely to be delimited unless the amount of newly detected infested area decreases, on average, by at least 50% per annum. As a result of control activities implemented, on average approximately 70% (range, 44 to 86%) of active infestations progressed to the monitoring phase in the year following their detection. Simulations suggest that increasing this rate of transition will not increase E to a significant extent. The rate of reversion of infestations from the monitoring phase to the active phase decreased logarithmically with time since last detection, but it is likely that lower rates of reversion would accelerate the trend toward extirpation. Program performance with respect to the delimitation criterion has been variable; performance with respect to the extirpation criterion would be improved considerably by the development and application of cost-effective methods for eliminating branched broomrape soil seed populations.

Connecting the space between design and research: Explorations in participatory research supervision

In this article we offer a single case study using an action research method for gathering and analysing data offering insights valuable to both design and research supervision practice. We do not attempt to generalise from this single case, but offer it as an instance that can improve our understanding of research supervision practice. We question the conventional ‘dyadic’ models of research supervision and outline a more collaborative model, based on the signature pedagogy of architecture: the design studio. A novel approach to the supervision of creatively oriented post-graduate students is proposed, including new approaches to design methods and participatory supervision that draw on established design studio practices. This model collapses the distance between design and research activities. Our case study involving Research Masters student supervision in the discipline of Architecture, shows how ‘connected learning’ emerges from this approach. This type of learning builds strong elements of creativity and fun, which promote and enhance student engagement. The results of our action research suggests that students learn to research more easily in such an environment and supervisory practices are enhanced when we apply the techniques and characteristics of design studio pedagogy to the more conventional research pedagogies imported from the humanities. We believe that other creative disciplines can apply similar tactics to enrich both the creative practice of research and the supervision of HDR students.

Phase relations between Al2O3---Cr2O3 and FeAl2O4---FeCr2O4 solid solutions at 1823 K

Tie-lines between the corundum and spinel solid solutions have been determined experimentally at 1823 K. Next, activities of FeCr2O4 and FeAl2O4 in the spinel solid solution were determined by combining the tie-line data with literature values for the activities of Cr2O3 and Al2O3 in the corundum phase. Activities and the Gibbs energy of mixing for the spinel solid solution were also obtained from a model based on cation distribution between nonequivalent crystallographic sites in the oxide lattice. The difference between the Gibbs energy of mixing obtained experimentally and from the model has been attributed to a strain enthalpy term which is relatively unchanged in magnitude from the reported at 1373 K. The integral enthalpy of mixing obtained from experimental data at 1373 and 1823 K using the second law is compared with the model result.

How widespread is Parthenium hysterophorus and its biological control agent Zygogramma bicolorata in South Asia?

Parthenium hysterophorus is a weed of global significance causing severe economic, environmental, human and animal health problems in Asia, Africa, Australia and the Pacific. In South Asia, P. hysterophorus occurs in India, Pakistan, Sri Lanka, Bangladesh and Nepal. A host-specific leaf-feeding beetle Zygogramma bicolorata from Mexico was introduced into India in 1984, as a biological control agent for P. hysterophorus. In this study, a GIS-based distribution map of P. hysterophorus and its biological control agent Z. bicolorata in South Asia based on meta-analysis is presented. The map highlights the limited published information on P. hysterophorus incidence in many of the states and territories in India, as well as in neighbouring Bangladesh, Bhutan, Nepal and Pakistan. Incidence of Z. bicolorata was recorded as three distinct clusters, covering many states in India. In Pakistan, Z. bicolorata was recorded in the Punjab region bordering India. A CLIMEX model based on the current distribution of Z. bicolorata in India suggests that the geographic range of this agent in India and Pakistan can extend to other P. hysterophorus-infested areas in the region. The CLIMEX model also suggests that all of Bangladesh and Sri Lanka, and parts of Nepal are climatically suitable for Z. bicolorata.

The effect of data sources and quality on the predictive capacity of CLIMEX models: an assessment of Teleonemia scrupulosa and Octotoma scabripennis for the biocontrol of Lantana camara in Australia

Understanding the effects of different types and quality of data on bioclimatic modeling predictions is vital to ascertaining the value of existing models, and to improving future models. Bioclimatic models were constructed using the CLIMEX program, using different data types – seasonal dynamics, geographic (overseas) distribution, and a combination of the two – for two biological control agents for the major weed Lantana camara L. in Australia. The models for one agent, Teleonemia scrupulosa Stål (Hemiptera:Tingidae) were based on a higher quality and quantity of data than the models for the other agent, Octotoma scabripennis Guérin-Méneville (Coleoptera: Chrysomelidae). Predictions of the geographic distribution for Australia showed that T. scrupulosa models exhibited greater accuracy with a progressive improvement from seasonal dynamics data, to the model based on overseas distribution, and finally the model combining the two data types. In contrast, O. scabripennis models were of low accuracy, and showed no clear trends across the various model types. These case studies demonstrate the importance of high quality data for developing models, and of supplementing distributional data with species seasonal dynamics data wherever possible. Seasonal dynamics data allows the modeller to focus on the species response to climatic trends, while distributional data enables easier fitting of stress parameters by restricting the species envelope to the described distribution. It is apparent that CLIMEX models based on low quality seasonal dynamics data, together with a small quantity of distributional data, are of minimal value in predicting the spatial extent of species distribution.

Population structure of South African and Australian Pyrenophora teres isolates.

There are two recognized forms of the disease net blotch of barley: the net form caused by Pyrenophora teres f. teres (PTT) and the spot form caused by P. teres f. maculata (PTM). In this study, amplified fragment length polymorphism analysis was used to investigate the genetic diversity and population structure of 60 PTT and 64 PTM isolates collected across Australia (66 isolates) and in the south-western Cape of South Africa (58 isolates). For comparison, P. tritici-repentis, Exserohilum rostratum and Bipolaris sorokiniana samples were also included in the analyses. Both distance-and model-based cluster analyses separated the PTT and PTM isolates into two strongly divergent genetic groups. Significant variation was observed both among the South African and Australian populations of PTT and PTM and among sampling locations for the PTT samples. Results suggest that sexual reproduction between the two forms is unlikely and that reproduction within the PTT and PTM groups occurs mainly asexually.

An investigation of solid adamantane by a modified isothermal-isobaric ensemble Monte Carlo simulation

Isothermal-isobaric ensemble Monte Carlo simulation studies of adamantane have been carried out at different temperatures. Thermodynamic properties and radial distribution functions calculated by employing a simple potential model based on sitesite interactions show good agreement with experiment and suggest that the solid is orientationally disordered at high temperatures.

Oxidative and photooxidative degradation of poly(acrylic acid)

The oxidative degradation of poly(acrylic acid) (PAA), a water soluble polymer, was studied at various temperatures with different concentrations of persulfates, potassium persulfate (KPS), ammonium persulfate (APS) and sodium persulfate (SPS). The photodegradation of PAA was also examined with APS as oxidizer. The degraded samples were analyzed for the time evolution of molecular weight distribution by gel permeation chromatography. A theoretical model based on the continuous distribution kinetics was developed that accounted for the polymer degradation and the dissociation of persulfate. The rate coefficients for the oxidative and photooxidative degradation of PAA were determined from the parametric fit of the model with experimental data. The rate of degradation increased with increasing amount of persulfate in both oxidative and photooxidative degradation. The rate of degradation also increased with increasing temperature in the case of oxidative degradation.

Population structure, effective population size and adverse effects of stocking in the endangered Australian eastern freshwater cod Maccullochella ikei

Microsatellite markers were used to examine spatio-temporal genetic variation in the endangered eastern freshwater cod Maccullochella ikei in the Clarence River system, eastern Australia. High levels of population structure were detected. A model-based clustering analysis of multilocus genotypes identified four populations that were highly differentiated by F-statistics (FST = 0· 09 − 0· 49; P < 0· 05), suggesting fragmentation and restricted dispersal particularly among upstream sites. Hatchery breeding programmes were used to re-establish locally extirpated populations and to supplement remnant populations. Bayesian and frequency-based analyses of hatchery fingerling samples provided evidence for population admixture in the hatchery, with the majority of parental stock sourced from distinct upstream sites. Comparison between historical and contemporary wild-caught samples showed a significant loss of heterozygosity (21%) and allelic richness (24%) in the Mann and Nymboida Rivers since the commencement of stocking. Fragmentation may have been a causative factor; however, temporal shifts in allele frequencies suggest swamping with hatchery-produced M. ikei has contributed to the genetic decline in the largest wild population. This study demonstrates the importance of using information on genetic variation and population structure in the management of breeding and stocking programmes, particularly for threatened species.

Eliciting and encoding expert knowledge on variable selection into classical or Bayesian species distribution models

The quality of species distribution models (SDMs) relies to a large degree on the quality of the input data, from bioclimatic indices to environmental and habitat descriptors (Austin, 2002). Recent reviews of SDM techniques, have sought to optimize predictive performance e.g. Elith et al., 2006. In general SDMs employ one of three approaches to variable selection. The simplest approach relies on the expert to select the variables, as in environmental niche models Nix, 1986 or a generalized linear model without variable selection (Miller and Franklin, 2002). A second approach explicitly incorporates variable selection into model fitting, which allows examination of particular combinations of variables. Examples include generalized linear or additive models with variable selection (Hastie et al. 2002); or classification trees with complexity or model based pruning (Breiman et al., 1984, Zeileis, 2008). A third approach uses model averaging, to summarize the overall contribution of a variable, without considering particular combinations. Examples include neural networks, boosted or bagged regression trees and Maximum Entropy as compared in Elith et al. 2006. Typically, users of SDMs will either consider a small number of variable sets, via the first approach, or else supply all of the candidate variables (often numbering more than a hundred) to the second or third approaches. Bayesian SDMs exist, with several methods for eliciting and encoding priors on model parameters (see review in Low Choy et al. 2010). However few methods have been published for informative variable selection; one example is Bayesian trees (O’Leary 2008). Here we report an elicitation protocol that helps makes explicit a priori expert judgements on the quality of candidate variables. This protocol can be flexibly applied to any of the three approaches to variable selection, described above, Bayesian or otherwise. We demonstrate how this information can be obtained then used to guide variable selection in classical or machine learning SDMs, or to define priors within Bayesian SDMs.

State Dependent Attempt Rate Modeling of Single Cell IEEE 802.11 WLANs with Homogeneous Nodes and Poisson Arrivals

Analytical models of IEEE 802.11-based WLANs are invariably based on approximations, such as the well-known mean-field approximations proposed by Bianchi for saturated nodes. In this paper, we provide a new approach for modeling the situation when the nodes are not saturated. We study a State Dependent Attempt Rate (SDAR) approximation to model M queues (one queue per node) served by the CSMA/CA protocol as standardized in the IEEE 802.11 DCF. The approximation is that, when n of the M queues are non-empty, the attempt probability of the n non-empty nodes is given by the long-term attempt probability of n saturated nodes as provided by Bianchi's model. This yields a coupled queue system. When packets arrive to the M queues according to independent Poisson processes, we provide an exact model for the coupled queue system with SDAR service. The main contribution of this paper is to provide an analysis of the coupled queue process by studying a lower dimensional process and by introducing a certain conditional independence approximation. We show that the numerical results obtained from our finite buffer analysis are in excellent agreement with the corresponding results obtained from ns-2 simulations. We replace the CSMA/CA protocol as implemented in the ns-2 simulator with the SDAR service model to show that the SDAR approximation provides an accurate model for the CSMA/CA protocol. We also report the simulation speed-ups thus obtained by our model-based simulation.

Microstructural evolution and grain boundary sliding in a superplastic magnesium AZ31 alloy

Tensile experiments on a fine-grained single-phase Mg–Zn–Al alloy (AZ31) at 673 K revealed superplastic behavior with an elongation to failure of 475% at 1 × 10−4 s−1 and non-superplastic behavior with an elongation to failure of 160% at 1 × 10−2 s−1; the corresponding strain rate sensitivities under these conditions were 0.5 and 0.2, respectively. Measurements indicated that the grain boundary sliding (GBS) contribution to strain ξ was 30% under non-superplastic conditions; there was also a significant sharpening in texture during such deformation. Under superplastic conditions, ξ was 50% at both low and high elongations of 20% and 120%; the initial texture became more random under such conditions. In non-superplastic conditions, deformation occurred under steady-state conditions without grain growth before significant flow localization whereas, under superplastic conditions, there was grain growth during the early stages of deformation, leading to strain hardening. The grains retained equiaxed shapes under all experimental conditions. Superplastic deformation is attributed to GBS, while non-superplastic deformation is attributed to intragranular dislocation creep with some contribution from GBS. The retention of equiaxed grain shapes during dislocation creep is consistent with a model based on local recovery related to the disturbance of triple junctions.