Arsenate-induced phosphate release from soils and its effect on plant phosphorus

Adsorption of arsenic onto soil was investigated as a means of understanding arsenic-induced release of phosphate. In batch adsorption experiments As adsorption was accompanied by P desorption. At low As additions, the ratio As adsorbed: P desorbed remained constant. At higher As additions, P desorption reached a maximum while As adsorption continued to increase. The P desorption maximum coincided with an increase in pH. Barley plants were grown on soils spiked with arsenate (0-360 mg As kg(-1)) to investigate the effect on plant growth and P uptake. As arsenic concentration increased, above ground plant yield decreased and the plants showed symptoms typical of As toxicity and P deficiency. At low As additions to the soil, uptake of As and P by barley increased. At higher As additions P uptake decreased. It is argued that this was due to the change in As:P ratio in the soil solution. It is concluded that input of arsenic to the soil could mobilise phosphate. Crop yield is likely to be affected, either due to reduced phosphate availability at low arsenic additions or arsenic toxicity at higher additions.

Modelling niches of arbitrary shape in genetic algorithms using Niche Linkage in the Dynamic Niche Clustering framework

We present some additions to a fuzzy variable radius niche technique called Dynamic Niche Clustering (DNC) (Gan and Warwick, 1999; 2000; 2001) that enable the identification and creation of niches of arbitrary shape through a mechanism called Niche Linkage. We show that by using this mechanism it is possible to attain better feature extraction from the underlying population.

Feasibility of using dialysis for determining calcium ion concentration and pH in calcium-fortified soymilk at high temperature

Dialysis was performed to examine some of the properties of the soluble phase of calcium (Ca) fortified soymilk at high temperatures. Dialysates were obtained while heating soymilk at temperatures of 80 and 100 °C for 1 h and 121 °C for 15 min. It was found that the pH, total Ca, and ionic Ca of dialysates obtained at high temperature were all lower than in their corresponding nonheated Ca-fortified soymilk. Increasing temperature from 80 to 100 °C hardly affected Ca ion concentration ([Ca2+]) of dialysate obtained from Ca chloride-fortified soymilk, but it increased [Ca2+] in dialysates of Ca gluconate-fortified soymilk and Ca lactate-fortified soymilk fortified with 5 to 6 mM Ca. Dialysates obtained at 100 °C had lower pH than dialysate prepared at 80 °C. Higher Ca additions to soymilk caused a significant (P≤ 0.05) reduction in pH and an increase in [Ca2+] of these dialysates. When soymilk was dialyzed at 121 °C, pH, total Ca, and ionic Ca were further reduced. Freezing point depression (FPD) of dialysates increased as temperature increased but were lower than corresponding soymilk samples. This approach provides a means of estimating pH and ionic Ca in soymilks at high temperatures, in order to better understand their combined role on soymilk coagulation.

Small x resummations confronted with F2(x, Q2) data

It has been observed recently that a consistent LO BFKL gluon evolution leads to a steep growth of F2(x, Q2) for x → 0 almost independently of Q2. We show that current data from the DESY HERA collider are precise enough to finally rule out a pure BFKL behaviour in the accessible small x region. Several attempts have been made by other groups to treat the BFKL type small x resummations instead as additions to the conventional anomalous dimensions of the successful renormalization group “Altarelli-Parisi” equations. We demonstrate that all presently available F2 data, in particular at lower values of Q2, can not be described using the presently known NLO (two-loop consistent) small x resummations. Finally we comment on the common reason for the failure of these BFKL inspired methods which result, in general, in too steep >x-dependencies as x → 0.

Clubroot (Plasmodiophora brassicae Woronin): an agricultural and biological challenge worldwide

Clubroot disease and the causal microbe Plasmodiophora brassicae offer abundant challenges to agriculturists and biological scientists. This microbe is well fitted for the environments which it inhabits. Plasmodiophora brassicae exists in soil as microscopic well protected resting spores and then grows actively and reproduces while shielded inside the roots of host plants. The pathogen is active outside the host for only short periods. Consequently, scientific studies are made challenging by the biological context of the host and pathogen and the technology required to investigate and understand that relationship. Controlling clubroot disease is a challenge for farmers, crop consultants and plant pathology practitioners because of the limited options which are available. Full symptom expression happens solely in members of the Brassicaceae family. Currently, only a few genes expressing strong resistance to P. brassicae are known and readily available. Agrochemical control is similarly limited by difficulties in molecule formulation which combines efficacy with environmental acceptability. Manipulation of husbandry encouraging improvements in soil structure, texture, nutrient composition and moisture content can reduce populations of P. brassicae. Integrating such strategies with rotation and crop management will reduce but not eliminate this disease. There are indications that forms of biological competition may be mobilised as additions to integrated control strategies. The aim of this review is to chart key themes in the development of scientific biological understanding of this host-pathogen relationship by offering signposts to grapple with clubroot disease which devastates crops and their profitability. Particular attention is given to the link between soil and nutrient chemistry and activity of this microbe.

Processes controlling surface, bottom and lateral melt of Arctic sea ice in a state of the art sea ice model

We present a modelling study of processes controlling the summer melt of the Arctic sea ice cover. We perform a sensitivity study and focus our interest on the thermodynamics at the ice–atmosphere and ice–ocean interfaces. We use the Los Alamos community sea ice model CICE, and additionally implement and test three new parametrization schemes: (i) a prognostic mixed layer; (ii) a three equation boundary condition for the salt and heat flux at the ice–ocean interface; and (iii) a new lateral melt parametrization. Recent additions to the CICE model are also tested, including explicit melt ponds, a form drag parametrization and a halodynamic brine drainage scheme. The various sea ice parametrizations tested in this sensitivity study introduce a wide spread in the simulated sea ice characteristics. For each simulation, the total melt is decomposed into its surface, bottom and lateral melt components to assess the processes driving melt and how this varies regionally and temporally. Because this study quantifies the relative importance of several processes in driving the summer melt of sea ice, this work can serve as a guide for future research priorities.

A case study of the direct radiative effect of biomass burning aerosols on precipitation in the Eastern Amazon

Numerical experiments with the Brazilian additions to the Regional Atmospheric Modeling System were performed with two nested grids (50 and 10 km horizontal resolution, respectively) with and without the effect of biomass burning for 8 different situations for 96 h integrations. Only the direct radiative effect of aerosols is considered. The results were analyzed in large areas encompassing the BR163 road (one of the main areas of deforestation in the Amazon). mainly where most of the burning takes place. The precipitation change due to the direct radiative impact of biomass burning is generally negative (i.e., there is a decrease of precipitation). However, there are a few cases with a positive impact. Two opposite forcing mechanisms were explored: (a) the thermodynamic forcing that is generally negative in the sense that the aerosol tends to stabilize the lower atmosphere and (b) the dynamic impact associated with the low level horizontal pressure gradients produced by the aerosol plumes. In order to understand the non-linear relationship between the two effects, experiments were performed with 4-fold emissions. In these cases, the dynamic effect overcomes the stabilization produced by the radiative forcing and precipitation increase is observed in comparison with the control experiment. This study suggests that. in general, the biomass burning radiative forcing decreases the precipitation. However, very large concentrations of aerosols may lead to an increase of precipitation due to the dynamical forcing associated with the horizontal pressure gradients. (C) 2009 Elsevier B.V. All rights reserved.

Hardenability reduction in VN microalloyed eutectoid steels

By dilatometry, it is shown that vanadium microalloying additions to eutectoid carbon steels, which also contain an increased level of nitrogen, cause a marked decrease in hardenability when transforming from fine grained austenite.

Faking it for real

Jean Baudrillard suggests that the supremacy of the simulacra is a modern development, reality a construction of the U.S. His argument, given the U.S. penchant for breaking and remaking the world in its own image (it is, in the language of Baudrillard, both iconoclast and iconolater), is strong. However, writers, artists, and philosophers have been pondering the reign of illusion for millennia. Plato described the world as a place of simulations that left us wanting. For Shakespeare, the world was a stage of fools; the play was that of an idiot. Goya presented the world as a dream of reason that gave birth to the monsters he painted. Borges (like Shakespeare and also perhaps Goya and Plato) was obsessed with what he refers to in "Tlön, Uqbar, Orbis Tertius" as the "atrocious or banal" idea that reality, as we know it (which is, of course, the only perspective of it that we can have), is fake. The three books under review here, Ian Miller's Faking It, Penny Cousineau-Levine's Faking Death: Canadian Art Photography and the Canadian Imagination, and Paul Matthew St Pierre's A Portrait of the Artist as Australian: L'Oeuvre bizarre de Barry Humphries, can be considered additions to the oeuvre fascinated and troubled by what Borges calls the "phantasmagorias" of our world

The use of home experimentation kits for distance students in first-year undergraduate electronics

Laboratory and practical classes are an important part of the education of students in electronics and electrical engineering. "Hands-on" experience is critical for any engineer working in these fields in particular. For many years, delivering engineering practicals to distance-education students has been a tremendous challenge for universities. For a number of years now, students enrolled in the common first-year electronics course by distance mode at Deakin University have received a home experimentation kit. Using the kit and a laboratory manual, students are required to complete a number of experiments based on components included in the kit. The kit supports a full range of practical activities for digital electronics, and a more limited range of activities for analog electronics. With the kit, off campus students are supplied software for simulating AC electronic circuits, such as amplifiers and rectifiers. In this report we examine the past use of this kit and software,
review anecdotal student experiences with the package, and propose changes to it and to other curriculum resources, aiming to enhance the use of the kit by distance students. Key curriculum resources planned are a web-based 'companion' for the components in and the use of the kit, and two additions to the kit itself: a battery powered function generator, and a PC-based oscilloscope.

Determinants of native avian richness in suburban remnant vegetation : implications for conservation planning

While urban areas are increasingly recognized as having potential value for biodiversity conservation, the relationship between biodiversity and the structure and configuration of the urban landscape is poorly understood. In this study we surveyed birds in 39 remnant patches of native vegetation of various sizes (range 1–107 ha) embedded in the suburban matrix in Melbourne, Australia. The total richness of species within remnants was strongly associated with the size of remnants. Remnant-reliant species displayed a much stronger response to remnant area than matrix-tolerant species indicating the importance of large remnants in maintaining representative bird assemblages. Large remnants are important for other ecological groups of species including migratory species, ground foraging birds and canopy foraging birds. Other landscape (e.g. amount of riparian vegetation) and structural components (e.g. shrub cover) of remnants have a lesser role in determining the richness of individual remnants. This research provides conservation managers and planners with a hierarchical process to reserve design and management in order to conserve the highest richness of native species within urban areas. First of all, conservation efforts should preferentially focus on the retention of larger remnants of native vegetation. Second, where possible, riparian vegetation should be included within reserves or, where it is already present, should be carefully managed to ensure its integrity. Third, efforts should be focused at maintaining appropriate habitat and vegetation structure and complexity.

The sociology of Pierre Bourdieu and researching education policy

Bourdieu did not write anything explicitly about education policy. Despite this neglect, we agree with van Zanten that his theoretical concepts and methodological approaches can contribute to researching and understanding educational policy in the context of globalisation and the economising of it. In applying Bourdieu's theory and methodology to research in education policy, we focus on developing his work to understand what we call 'cross-field effects' and for exploring the emergence of a 'global education policy field'. These concepts are derived from some of our recent research concerning globalisation and mediatisation of education policy. The paper considers three separate issues. The first deals with Bourdieu' s primary 'thinking tools', namely practice, habitus,capitals and fields and their application to policy studies. The second and third sections consider two additions to Bourdieu's thinking tools, as a way to reconceptualise the functioning of policy if considered as a social field. More specifically, the second section develops an argument around cross-field effects, as a way to group together, research and describe policy effects. The third section develops an argument about an emergent global education policy field, and considers ways that such a field affects national education policy fields.

Dynamic shot suggestion filtering for home video based on user performance

This paper presents novel additions to our existing amateur media creation framework. The framework provides at-capture guidance to enable the home movie maker to realize their aesthetic and narrative goals and automation of post-production editing. A common problem with the amateur filming context is its contingent nature, which often results in the failure to gain footage vital to the user's goals, even with at-capture software embedding. Accordingly, we have modelled minimizing the difference between target and captured footage at a given time during filming as a probability distribution divergence problem. We apply two policies of feedback to the user on their performance, passive communication via a suggestion desirability measure, and active filtering of undesirable suggestions. We demonstrate the framework using each policy with a simulation of various user and filming situations with promising results.

Image fusion metrics : evolution in a nutshell

Image fusion process merges two images into a single more informative image. Objective image fusion per- formance metrics rely primarily on measuring the amount of information transferred from each source image into the fused image. Objective image fusion metrics have evolved from image processing dissimilarity metrics. Additionally, researchers have developed many additions to image dissimilarity metrics in order to better value the local fusion worthy features in source images. This paper studies the evolution of objective image fusion performance metrics and their subjective and objective validation. It describes how a fusion performance metric evolves starting with image dissimilarity metrics, its realization into image fusion contexts, its localized weighting factors and the validation process.

International housing market analysis based on housing commencements

Additions to the aggregate housing stock are a broad measure of the state of an economy and overall level of confidence in a particular region over a designated period. This is due to the direct and indirect effect (e.g. employment in the housing construction industry) upon on the local economy and is linked to the confidence of local households in the future direction of housing investment, the level of housing affordability by households as related to employment levels and the relationship between supply and demand in each region. Another consideration is the ability of the government to monitor and successfully intervene in the operation of the household market (e.g. mortgage interest rates) with the intent of restricting an over-supply situation which may take years to fully recover. The analysis in this section examines new housing commencements for Scotland, Australia, USA and Canada over an extended time period with the specific focus placed on the periods before, during and after the high profile global financial crisis in 2007-2008. The graph in Figure 1 was adapted from data sourced from The Scottish Government (2013) and covers the 15-year period between 1998 and 2012. With the exception of 1999 there were been relatively few years with substantial additions to the housing market. However, the effect of the GFC can clearly be observed post 2007 although by 2012 there was relatively change from the previous year.