Predator control promotes invasive dominated ecological states

Invasive species are regarded as one of the top five drivers of the global extinction crisis. In response, extreme measures have been applied in an attempt to control or eradicate invasives, with little success overall. We tested the idea that state shifts to invasive dominance are symptomatic of losses in ecosystem resilience, due to the suppression of apex predators. This concept was investigated in Australia where the high rate of mammalian extinctions is largely attributed to the destructive influence of invasive species. Intensive pest control is widely applied across the continent, simultaneously eliminating Australia’s apex predator, the dingo (Canis lupus dingo). We show that predator management accounts for shifts between two main ecosystem states. Lethal control fractures dingo social structure and leads to bottom-up driven increases in invasive mesopredators and herbivores. Where control is relaxed, dingoes re-establish top–down regulation of ecosystems, allowing for the recovery of biodiversity and productivity.

The productivity-wage and productivity-employment nexus : a panel data analysis of Indian manufacturing

This article investigates the long-run relationship between labour productivity and employment, and between labour productivity and real wages in the case of the Indian manufacturing sector. The panel data set consists of 17 two-digit manufacturing industries for the period 1973–1974 to 1999–2001. We find that productivity-wages and productivity-employment are panel cointegrated for all industries. We find that both employment and real wages exert a positive effect on labour productivity. We argue that flexible labour market has a significant influence on manufacturing productivity, employment and real wages in the case of Indian manufacturing.

Construction capital productivity measurement using a data envelopment analysis

During the past few decades, the construction industry has experienced a series of changes including the innovation of construction technologies and the enhancement of management strategies. These improvements should have had a considerable effect on industrial efficiency and productivity performance, but research is needed to address whether the capital productivity levels of the construction industry have in fact shown such a huge improvement. This paper aims to develop an analysis procedure to measure capital productivity changes and to reasonably quantify factors affecting productivity levels in the construction industry. Based on the data envelopment analysis method, this research has developed a novel model measuring capital productivity and has applied it to the Australian construction industry. The numerical results indicate that the average annual capital productivity levels of the construction industry are slowly growing in all the Australian states and territories except for Queensland and Western Australia. In addition, construction technologies are shown to have a close relationship with the changes in capital productivity according to the temporal-spatial comparisons of productivity indices. The research findings are expected to be beneficial for making policy and strategic decisions to improve the capital productivity performance.

Attack vector analysis and privacy-preserving social network data publishing

This paper addresses the problem of privacy-preserving data publishing for social network. Research on protecting the privacy of individuals and the confidentiality of data in social network has recently been receiving increasing attention. Privacy is an important issue when one wants to make use of data that involves individuals' sensitive information, especially in a time when data collection is becoming easier and sophisticated data mining techniques are becoming more efficient. In this paper, we discuss various privacy attack vectors on social networks. We present algorithms that sanitize data to make it safe for release while preserving useful information, and discuss ways of analyzing the sanitized data. This study provides a summary of the current state-of-the-art, based on which we expect to see advances in social networks data publishing for years to come.

Early childhood science education : do Australian publishing trends represent world publishing trends?

A literature search of both Australian early childhood journals and Australian science education journals provides a compelling picture of science education in Australian early childhood in the recent past and the previous 40 years. Whilst a previous review of the literature found that there were concerns over the early childhood educators' confidence in teaching science, particularly physical sciences, current research indicates that this problem is still prevalent. The historical perspective also found that there was a distinctive approach evolving in early childhood science education, however further research into the place of science in the cognitive domain of early childhood was required. The more recent literature search found that as an area of investigation, early childhood science is still a neglected research area and there is still much scope for the development of theories and analysis of early childhood science education. The literature search was undertaken scanning for titles which included science education and early childhood in several Australian early childhood journals and Australian science education journals, although it is acknowledged that some articles may have been sent to international journals.

Managing fire mosaics for small mammal conservation : a landscape perspective

1.Fire is a major driver of ecosystem structure and function worldwide. It is also widely used as a management tool to achieve conservation goals. A common objective is the maintenance of 'fire mosaics' comprising spatially heterogeneous patches of differing fire history. However, it is unclear what properties of fire mosaics most enhance conservation efforts. Here we focus on the spatial and temporal properties of fire-prone landscapes that influence the distribution of small mammals.

2.We surveyed small mammals in 28 landscapes (each 12·6km²) representing a range of fire histories in the Murray Mallee region (104 000km²) of semi-arid Australia. Generalised linear mixed models were used to examine the influence of five landscape properties on the capture rate of individual species and the species richness of native small mammals. We investigated the influence of the proportional extent of fire age-classes, the diversity of fire age-classes, the extent of the dominant vegetation type, rainfall history and biogeographic context.

3.Three of four study species were associated with the spatial extent of fire age-classes. Older vegetation was found to provide important habitat for native small mammals. Overall, however, rainfall history and biogeographic context were dominant influences: for example, the species richness of native mammals was positively associated with above-average rainfall. There was little evidence that the diversity of fire age-classes influenced either the capture rate of individual species or species richness.

4.Synthesis and applications. In fire-prone environments, habitat availability can change markedly over short time-scales. Sufficient habitat at a suitable seral stage within the landscape is a key requirement for species conservation. In mallee ecosystems, the retention of older vegetation is recommended to create more desirable fire mosaics for native small mammals. In addition to such spatial properties of mosaics that are amenable to manipulation, an understanding of how ecological processes affect the biota (such as variation in rainfall-driven productivity) is also essential for informed conservation management.

Labour productivity measurement with variable returns to scale in Australia's construction industry

As an important productivity indicator, the change of labour productivity is one indispensable marker in determining the rise or fall of overall industrial performance. This study aims to address whether the labour productivity level of the Australian construction industry has, in fact, shown a huge improvement during the last few decades. This article constructs a measuring method estimating labour productivity changes based on the data envelopment analysis technique with variable returns to scale. By adopting a production frontier approach, the labour productivity index can be broken down into components attributable to efficiency change, technological progress and capital accumulation. The numerical results exemplified by a single-input and single-output system indicate that the average annual labour productivity levels of the construction industry are slowly growing in all the Australian states and territories. However, the year-on-year change in the overall labour productivity performance does not maintain a long-term increase over the period 1990–2008. The study forms the basis for further industrial productivity research. Proposals and recommendations are expected to be beneficial for making policy and strategic decisions to improve the performance of the construction industry.

Fiber generators in needleless electrospinning

The conventional electrospinning often uses a needle-like nozzle to produce nanofibers with a very low production rate. Despite the enormous application potential, needle electrospun nanofibers meet difficulties in broad applications in practice, due to the lack of an economic and efficient way to scale up the electrospinning process. Recently, needleless electrospinning has emerged as a new electrospinning mode and shown ability to produce nanofibers on large-scales. It has been established that the fiber generator, also referred to as “spinneret” in this paper, in needleless electrospinning plays a key role in scaling up the nanofiber production. This paper summarizes the recent advances in the development of needleless spinnerets and their influences on electrospinning process, nanofiber quality, and productivity.

Kin selection, not group augmentation, predicts helping in an obligate cooperatively breeding bird

Kin selection theory has been the central model for understanding the evolution of cooperative breeding, where non-breeders help bear the cost of rearing young. Recently, the dominance of this idea has been questioned; particularly in obligate cooperative breeders where breeding without help is uncommon and seldom successful. In such systems, the direct benefits gained through augmenting current group size have been hypothesized to provide a tractable alternative (or addition) to kin selection. However, clear empirical tests of the opposing predictions are lacking. Here, we provide convincing evidence to suggest that kin selection and not group augmentation accounts for decisions of whether, where and how often to help in an obligate cooperative breeder, the chestnut-crowned babbler (Pomatostomus ruficeps). We found no evidence that group members base helping decisions on the size of breeding units available in their social group, despite both correlational and experimental data showing substantial variation in the degree to which helpers affect productivity in units of different size. By contrast, 98 per cent of group members with kin present helped, 100 per cent directed their care towards the most related brood in the social group, and those rearing half/full-sibs helped approximately three times harder than those rearing less/non-related broods. We conclude that kin selection plays a central role in the maintenance of cooperative breeding in this species, despite the apparent importance of living in large groups.

Biological vulnerability of two exploited sharks of the genus Deania (Centrophoridae)

Life-history parameters of Deania calcea and Deania quadrispinosa suggested that their productivity was very low. Maturity (L_T50) occurs at c. 80% of maximum observed total lengths (L_T) for both species and sexes. A large proportion of mature females were neither pre-ovulatory nor pregnant, and the reproductive cycle included a distinct resting phase after pregnancy. For D. calcea, mean ovarian fecundity was 12 and maximum observed litter size was 10 (average of six); D. quadrispinosa averaged 17 pups per litter. Birth L_T was 28-33 cm for D. calcea and 23-25 cm for D. quadrispinosa. The male and female reproductive cycles were aseasonal, and consequently, the length of the reproductive cycle could not be determined. Preliminary ageing data from dorsal-spine growth bands suggested that female D. calcea lived to 31-36 years and males to 24-32 years. The L_T-at-age data using external bands on the spines showed maturity occurring at 15·5 years (males) and 21·5 years (females), whereas banding on the internal dentine indicated maturity at 10·5 and 17·5 years for males and females. Thus, a female lifetime of 31-36 years allowed for a maximum of 7 litters if a 2 year cycle is assumed or only five litters with a 3 year cycle, resulting in a lifetime fecundity of only 42 pups (2 year cycle) or even lower (3 year cycle).

The productivity and performance of Australia’s major banks since deregulation

The aim of this study is to present some measures of the performance of banks operating in Australia since the deregulation of the Australian financial system in early 1980s; including the periods of financial market instability (the early 1990s and mid to late 2000s). In undertaking this measurement two approaches will be used. The first simply applies standard financial indicators. The second approach applies data envelopment analysis (DEA), to determine Malmquist indices of the levels of and the changes in the efficiency and productivity of Australian banks. The empirical results demonstrate the effect of deregulation and periodic financial crisis’s on the performance of individual banks, and the major part of the Australian banking sector. Overall the productivity performance of the Australian banks tended to improve considerably in those periods of strongest economic growth (i.e. the mid 1980s and 2000s).