Occurrence of iron and associated bacterial populations in soils of a forested subtropical coastal catchment

Iron (Fe) biogeochemistry is potentially of environmental significance in plantation-forested, subtropical coastal ecosystems where soil disturbance and seasonal water logging may lead to elevation of Fe mobilization and associated water quality deterioration. Using wet-chemical extraction and laboratory cultivation, we examined the occurrence of Fe forms and associated bacterial populations in diverse soils of a representative subtropical Australian coastal catchment (Poona Creek). Total reactive Fe was abundant throughout 0e30 cm soil cores, consisting primarily of crystalline forms in well-drained sand soils and water-logged loam soils, whereas in water-logged, low clay soils, over half of total reactive Fe was present in poorly-crystalline forms due to organic and inorganic complexation, respectively. Forestry practices such as plantation clear-felling and replanting, seasonal water logging and mineral soil properties significantly impacted soil organic carbon (C), potentially-bioavailable Fe pools and densities of S-, but not Fe-, bacterial populations. Bacterial Fe(III) reduction and abiotic Fe(II) oxidation, as well as chemolithotrophic S oxidation and aerobic, heterotrophic respiration were integral to catchment terrestrial FeeC cycling. This work demonstrates bacterial involvement in terrestrial Fe cycling in a subtropical coastal circumneutral-pH ecosystem.

Common variation in the fibroblast growth factor receptor 2 gene is not associated with endometriosis risk

BACKGROUND Endometriosis is a polygenic disease with a complex and multifactorial aetiology that affects 8-10% of women of reproductive age. Epidemiological data support a link between endometriosis and cancers of the reproductive tract. Fibroblast growth factor receptor 2 (FGFR2) has recently been implicated in both endometrial and breast cancer. Our previous studies on endometriosis identified significant linkage to a novel susceptibility locus on chromosome 10q26 and the FGFR2 gene maps within this linkage region. We therefore hypothesized that variation in FGFR2 may contribute to the risk of endometriosis. METHODS We genotyped 13 single nucleotide polymorphisms (SNPs) densely covering a 27 kb region within intron 2 of FGFR2 including two SNPs (rs2981582 and rs1219648) significantly associated with breast cancer and a total 40 tagSNPs across 150 kb of the FGFR2 gene. SNPs were genotyped in 958 endometriosis cases and 959 unrelated controls. RESULTS We found no evidence for association between endometriosis and FGFR2 intron 2 SNPs or SNP haplotypes and no evidence for association between endometriosis and variation across the FGFR2 gene. CONCLUSIONS Common variation in the breast-cancer implicated intron 2 and other highly plausible causative candidate regions of FGFR2 do not appear to be a major contributor to endometriosis susceptibility in our large Australian sample.

Is there a physicality requirement at Common Law? : a survey of the Pre-NRDC cases discussing ‘Manufacture’

One of the fundamental issues that remains unresolved in patent law today, both in Australia and in other jurisdictions, is whether an invention must produce a physical effect or cause a physical transformation of matter to be patentable, or whether it is sufficient that an invention involves a specific practical application of an idea or principle to achieve a useful result. In short, the question is whether Australian patent law contains a physicality requirement. Despite being recently considered by the Federal Court, this is arguably an issue that has yet to be satisfactorily resolved in Australia. In its 2006 decision in Grant v Commissioner of Patents, the Full Court of the Federal Court of Australia found that the patentable subject matter standard is rooted in the physical, when it held that an invention must involve a physical effect or transformation to be patent eligible. That decision, however, has been the subject of scrutiny in the academic literature. This article seeks to add to the existing literature written in response to the Grant decision by examining in detail the key common law cases decided prior to the High Court’s watershed decision in National Research Development Corporation v Commissioner of Patents, which is the undisputed authoritative statement of principle in regards to the patentable subject matter standard in Australia. This article, in conjunction with others written by the author, questions the Federal Court’s assertion in Grant that the physicality requirement it established is consistent with existing law.

Haplotype analysis of two recurrent CDKN2A mutations in 10 melanoma families : evidence for common founders and independent mutations

Germ-line mutations in CDKN2A have been shown to predispose to cutaneous malignant melanoma. We have identified 2 new melanoma kindreds which carry a duplication of a 24bp repeat present in the 5' region of CDKN2A previously identified in melanoma families from Australia and the United States. This mutation has now been reported in 5 melanoma families from 3 continents: Europe, North America, and Australasia. The M53I mutation in exon 2 of CDKN2A has also been documented in 5 melanoma families from Australia and North America. The aim of this study was to determine whether the occurrence of the mutations in these families from geographically diverse populations represented mutation hotspots within CDKN2A or were due to common ancestors. Haplotypes of 11 microsatellite markers flanking CDKN2A were constructed in 5 families carrying the M53I mutation and 5 families carrying the 24bp duplication. There were some differences in the segregating haplotypes due primarily to recombinations and mutations within the short tandem-repeat markers; however, the data provide evidence to indicate that there were at least 3 independent 24bp duplication events and possibly only 1 original M53I mutation. This is the first study to date which indicates common founders in melanoma families from different continents.

Multifractal characterisation and analysis of complex networks

Complex networks have been studied extensively due to their relevance to many real-world systems such as the world-wide web, the internet, biological and social systems. During the past two decades, studies of such networks in different fields have produced many significant results concerning their structures, topological properties, and dynamics. Three well-known properties of complex networks are scale-free degree distribution, small-world effect and self-similarity. The search for additional meaningful properties and the relationships among these properties is an active area of current research. This thesis investigates a newer aspect of complex networks, namely their multifractality, which is an extension of the concept of selfsimilarity. The first part of the thesis aims to confirm that the study of properties of complex networks can be expanded to a wider field including more complex weighted networks. Those real networks that have been shown to possess the self-similarity property in the existing literature are all unweighted networks. We use the proteinprotein interaction (PPI) networks as a key example to show that their weighted networks inherit the self-similarity from the original unweighted networks. Firstly, we confirm that the random sequential box-covering algorithm is an effective tool to compute the fractal dimension of complex networks. This is demonstrated on the Homo sapiens and E. coli PPI networks as well as their skeletons. Our results verify that the fractal dimension of the skeleton is smaller than that of the original network due to the shortest distance between nodes is larger in the skeleton, hence for a fixed box-size more boxes will be needed to cover the skeleton. Then we adopt the iterative scoring method to generate weighted PPI networks of five species, namely Homo sapiens, E. coli, yeast, C. elegans and Arabidopsis Thaliana. By using the random sequential box-covering algorithm, we calculate the fractal dimensions for both the original unweighted PPI networks and the generated weighted networks. The results show that self-similarity is still present in generated weighted PPI networks. This implication will be useful for our treatment of the networks in the third part of the thesis. The second part of the thesis aims to explore the multifractal behavior of different complex networks. Fractals such as the Cantor set, the Koch curve and the Sierspinski gasket are homogeneous since these fractals consist of a geometrical figure which repeats on an ever-reduced scale. Fractal analysis is a useful method for their study. However, real-world fractals are not homogeneous; there is rarely an identical motif repeated on all scales. Their singularity may vary on different subsets; implying that these objects are multifractal. Multifractal analysis is a useful way to systematically characterize the spatial heterogeneity of both theoretical and experimental fractal patterns. However, the tools for multifractal analysis of objects in Euclidean space are not suitable for complex networks. In this thesis, we propose a new box covering algorithm for multifractal analysis of complex networks. This algorithm is demonstrated in the computation of the generalized fractal dimensions of some theoretical networks, namely scale-free networks, small-world networks, random networks, and a kind of real networks, namely PPI networks of different species. Our main finding is the existence of multifractality in scale-free networks and PPI networks, while the multifractal behaviour is not confirmed for small-world networks and random networks. As another application, we generate gene interactions networks for patients and healthy people using the correlation coefficients between microarrays of different genes. Our results confirm the existence of multifractality in gene interactions networks. This multifractal analysis then provides a potentially useful tool for gene clustering and identification. The third part of the thesis aims to investigate the topological properties of networks constructed from time series. Characterizing complicated dynamics from time series is a fundamental problem of continuing interest in a wide variety of fields. Recent works indicate that complex network theory can be a powerful tool to analyse time series. Many existing methods for transforming time series into complex networks share a common feature: they define the connectivity of a complex network by the mutual proximity of different parts (e.g., individual states, state vectors, or cycles) of a single trajectory. In this thesis, we propose a new method to construct networks of time series: we define nodes by vectors of a certain length in the time series, and weight of edges between any two nodes by the Euclidean distance between the corresponding two vectors. We apply this method to build networks for fractional Brownian motions, whose long-range dependence is characterised by their Hurst exponent. We verify the validity of this method by showing that time series with stronger correlation, hence larger Hurst exponent, tend to have smaller fractal dimension, hence smoother sample paths. We then construct networks via the technique of horizontal visibility graph (HVG), which has been widely used recently. We confirm a known linear relationship between the Hurst exponent of fractional Brownian motion and the fractal dimension of the corresponding HVG network. In the first application, we apply our newly developed box-covering algorithm to calculate the generalized fractal dimensions of the HVG networks of fractional Brownian motions as well as those for binomial cascades and five bacterial genomes. The results confirm the monoscaling of fractional Brownian motion and the multifractality of the rest. As an additional application, we discuss the resilience of networks constructed from time series via two different approaches: visibility graph and horizontal visibility graph. Our finding is that the degree distribution of VG networks of fractional Brownian motions is scale-free (i.e., having a power law) meaning that one needs to destroy a large percentage of nodes before the network collapses into isolated parts; while for HVG networks of fractional Brownian motions, the degree distribution has exponential tails, implying that HVG networks would not survive the same kind of attack.

Revealing common attributes of organizational identities using performance measurement systems

Identity is unique, multiple and dynamic. This paper explores common attributes of organisational identities, and examines the role of performance management systems (PMSs) on revealing identity attributes. One of the influential PMSs, the balanced scorecard, is used to illustrate the arguments. A case study of a public-sector organisation suggests that PMSs now place a value on the intangible aspects of organisational life as well as the financial, periodically revealing distinctiveness, relativity, visibility, fluidity and manageability of public-sector identities that sustain their viability. This paper contributes to a multi-disciplinary approach and its practical application, demonstrating an alternative pathway to identity-making using PMSs.

Photocatalytic disinfection of bacterial pollutants using suspended and immobilized TiO(2) powders

The photocatalytic disinfection of Enterobacter cloacae and Enterobacter coli using microwave (MW), convection hydrothermal (HT) and Degussa P25 titania was investigated in suspension and immobilized reactors. In suspension reactors, MW-treated TiO(2) was the most efficient catalyst (per unit weight of catalyst) for the disinfection of E. cloacae. However, HT-treated TiO(2) was approximately 10 times more efficient than MW or P25 titania for the disinfection of E. coli suspensions in surface water using the immobilized reactor. In immobilized experiments, using surface water a significant amount of photolysis was observed using the MW- and HT-treated films; however, disinfection on P25 films was primarily attributed to photocatalysis. Competitive action of inorganic ions and humic substances for hydroxyl radicals during photocatalytic experiments, as well as humic substances physically screening the cells from UV and hydroxyl radical attack resulted in low rates of disinfection. A decrease in colony size (from 1.5 to 0.3 mm) was noted during photocatalytic experiments. The smaller than average colonies were thought to occur during sublethal (•) OH and O(2) (•-) attack. Catalyst fouling was observed following experiments in surface water and the ability to regenerate the surface was demonstrated using photocatalytic degradation of oxalic acid as a model test system

Case studies of statutory interventions into the common law concept of charity

This paper considers four examples of statutory interventions into the common law concept of charity, namely, those of Pennsylvania, Barbados, the definition recommended by the Report of the Inquiry into the Definition of Charities in Australia, and the Recreational Charities legislation of the United Kingdom. It comments on some issues affecting each style of intervention. The paper does not argue against statutory intervention but submits that legislative changes are best made by deeming a particular purpose to be charitable, or not charitable, so that, except to that extent, the common law concept remains intact – this is the approach adopted by the Recreational Charities legislation.

Detecting common dynamics in transitory components

This paper considers VECMs for variables exhibiting cointegration and common features in the transitory components. While the presence of cointegration between the permanent components of series reduces the rank of the long-run multiplier matrix, a common feature among the transitory components leads to a rank reduction in the matrix summarizing short-run dynamics. The common feature also implies that there exists linear combinations of the first-differenced variables in a cointegrated VAR that are white noise and traditional tests focus on testing for this characteristic. An alternative, however, is to test the rank of the short-run dynamics matrix directly. Consequently, we use the literature on testing the rank of a matrix to produce some alternative test statistics. We also show that these are identical to one of the traditional tests. The performance of the different methods is illustrated in a Monte Carlo analysis which is then used to re-examine an existing empirical study. Finally, this approach is applied to provide a check for the presence of common dynamics in DSGE models.