Evolution of egg size and fertilisation efficiency in sea stars: large eggs are not fertilised more readily than small eggs in Patiriella (Echinodermata: Asteroidea)

Fertilisation kinetics theory suggests that, when sperm are limiting, the larger eggs of broadcast-spawning marine organisms ought to be fertilised more frequently than smaller eggs, because they provide a bigger target for searching sperm. Whilst this effect has been demonstrated within species, it is not known if this pattern holds among species. We tested whether a large difference in egg size between congeneric seastars with contrasting planktotrophic and lecithotrophic modes of development results in differences in the likelihood of eggs being fertilised in sperm-limiting situations. Measurement of egg sizes and sperm swimming speeds led to the prediction that the sperm–egg collision rate constant for Patiriella calcar (420-µm-diameter egg) should be nine times greater than for P. regularis (140-µm-diameter egg). Although the eggs of P. calcar should be fertilised at greater rates in low sperm concentrations, they were not. When gametes were allowed to mix for 10 s, the hypothesis that P. calcar eggs required less sperm than P. regularis to ensure 50% of eggs were fertilised was rejected. When gametes were mixed for 5 min, P. regularis eggs were more frequently fertilised, but the difference was not statistically significant. We conclude there must be a difference between these species in the likelihood that when a sperm finds a conspecific egg it can successfully fertilise. This apparent uncoupling of egg size and likelihood of fertilisation suggests that fertilisation is not a major constraint on the evolution of egg size in these seastars.

More than just a transaction: conceptualising industry-based networks for virtual trading communities

This paper addresses the questions of why failure in industry-based networks has been so persistent and whether it is possible to avoid failure and achieve success in internet based markets [iMarketplaces]. A better explanation of implementation failures is important for both improved empirical outcomes and theory building. We construct a theoretical framework based on Bijker’s technology frame (1995) and a contextualization typology developed by Nowotny, Scott and Gibbons (2001). The framework helps us understand how industry-based networks function, why they fail and how we can apply the framework to assist better empirical outcomes. In this paper we apply our framework to Food Connect Australia, a vertically integrated marketplace, representative of the first wave of B2B markets. Sponsors of these iMarketplaces were quick to see and exploit the opportunities online access offered to bring together large numbers of buyers and sellers in new ways. However a lack of understanding of firstly, what represented true value in these networks and secondly, how to achieve buy-in at sustainable levels, meant that many of these first wave sites failed. Application of our framework reveals why there has been a radical shift from the trading role originally envisioned for these sites to the information hub model of the iMarketplace that industry is now being urged to adopt (Berryman and Heck, 2001).

More dominant in their inactivity: consumer response and the adoption of digital TV in Australia

After much hesitation, discussion, and power brokering, Australia adopted digital TV for its Free-to air broadcasting on January 1, 2001. However, by December 2002, only a few thousand homes had adopted the technology. This paper examines the implementation and regulation of digital TV in Australia from the point of view of the ‘established base’ the new technology will replace, theories on diffusion and innovation of new technologies, and the Justification Model, which sees technology choice as social gambling. It then evaluates the various protectionist regulations and limitations imposed on the technology to safeguard the various stakeholders, the implementation strategies used, lack of digital content, marketing efforts, negative media coverage, and the economic realities of the technology, and argues that if consumers reject the technology altogether, it would lead to Australia missing the future applications of digital technology and the opportunity to address the issue of the ‘digital divide’ in the 21st century.

Mining more gold from web page hyperlinks

The development of the Internet has boosted prosperity of the World Wide Web, which is now a huge information source. Because of characteristics of the web, in most cases, traditional databasebased technologies are no longer suitable for web information retrieval and management. To effectively manage web information, it is necessary to reveal intrinsic relationships/structures among web information objects by eliminating noise factors. This paper proposes a mechanism that could be widely used in information processing, including web information processing and noise factor elimination for getting more intrinsic relationships. As an application case of this mechanism, one relevant web page finding algorithm is proposed to uncover intrinsic relationship among web pages from their hyperlink patterns, and find more semantic relevant web pages. The experimental evaluation shows the feasibility and effectiveness of the algorithm and demonstrates the potential of the proposed mechanism in web applications.

Consolidating one novel structure whilst constructing two more

This study reports the cognitive processing of a Year 8 female student (Kerri) during a test, and during her subsequent homework as she consolidated as part of abstracting; a topic of recent research interest. This case adds to the body of knowledge about how constructing and consolidating can occur simultaneously. The analysis captured the complexity of the cognitive processing, and their intertwined nature. Data was captured through lesson video, and post-lesson, video-stimulated reconstructive student interviews. It was found that Kerri’s constructing and consolidating included characteristics previously identified by others, and an additional feature. Her constructing included “branching” (Kidron & Dreyfus, 2004, p. 159); but unlike the case cited, one of these branches related to a new goal.

Including the designer in a more holistic understanding of ecologically sustainable design (ESD)

This paper backgrounds the current approach to ecologically sustainable design (ESD) while outlining the prevailing technological zeitgeist within which architecture operates. In differentiating between ecology and ecosophy a quantum shift in attitude is explored. This allows the psychodynamics behind the act of commitment to be brought up for discussion and places the designer within a more holistic understanding of ESD.

Empirical generalisation as an inadequate cognitive scaffold to theoretical generalisation of a more complex concept

The impact of prior learning on new learning is highlighted by the case of Dean, a Year 8 student who developed his own method to find the sum of the interior angles of a polygon without knowing why his method worked. Enriched transcripts and visual displays of the cognitive, social (Dreyfus, Hershkowitz, & Schwarz, 2001) and affective elements (Williams, 2002) of Dean's interrupted abstraction process informed the identification of factors that inhibited Dean's constructing process. It was found Dean possessed an empirical, not theoretical, generalization (Davydov, 1990) about sums of interior angles of triangles that was an inadequate cognitive artifact for constructing the new more complex theoretical generalization. The study suggests use of tasks designed with the opportunity develop assumed knowledge in conjunction with new concepts.

Observation of pain assessment and management- the complexities of clinical practice

• Pain assessment and management are complex issues that embrace physiological, emotional, cognitive, and social dimensions.

• This observational study sought to investigate nurse–patient interactions associated with pain assessment and management in hospitalized postsurgical patients in clinical practice settings.

• Twelve field observations were carried out on Registered Nurses' activities relating to pain with their assigned patients. All nurses were involved in direct patient care in one surgical unit of a metropolitan teaching hospital in Melbourne, Australia. Six observation times were identified as key periods for activities relating to pain, which included change of shift and high activity periods. Each observation period lasted 2 hours and was examined on two occasions.

• Four major themes were identified as barriers to effective pain management: nurses' responses to interruptions of activities relating to pain, nurses' attentiveness to patient cues of pain, nurses' varying interpretations of pain, and nurses' attempts to address competing demands of nurses, doctors and patients.

• These findings provide some understanding of the complexities impacting on nurses' assessment and management of postoperative pain. Further research using this observational methodology is indicated to examine these influences in more depth. This knowledge may form the basis for developing and evaluating strategic intervention programmes that analyse nurses' management of postoperative pain and, in particular, their administration of opioid analgesics.

Informed principal, moral hazard, and the value of a more informative technology

We analyze a principal-agent model with moral hazard in which the principal has private information about the technology. We characterize Perfect Bayesian Equilibria of the contracting game that possess the following properties: (i) a principal with a more informative technology ends up earning less profits than a principal with a less informative one does; (ii) compared to the complete information case, the actions implemented by the privately informed principal can be distorted; (iii) the agent can end up being better off when the principal has private information.

Re-badged environmental education: is ESD more than just a slogan?

In the field of environment-related education, the period from the early 70s to the present is marked by continuity and contestation. There has been a remarkable continuity of environmentrelated practice; and there has also been contestation in the language of the field, with terms like ecology education, environmental education and education for sustainable development becoming highly visible at different times. Presently, the environment-related work formerly known as ‘environmental education’ (EE) is being aggressively and extensively ‘re-badged’ as ‘education for sustainable development’ (ESD). This paper explores the role of slogans in the fields of environmental education and education for sustainable development.

A matrix-based model for web page community construction and more

The rapid development of network technologies has made the web a huge information source with its own characteristics. In most cases, traditional database-based technologies are no longer suitable for web information processing and management. For effectively processing and managing web information, it is necessary to reveal intrinsic relationships/structures among concerned web information objects such as web pages. In this work, a set of web pages that have their intrinsic relationships is called a web page community. This paper proposes a matrix-based model to describe relationships among concerned web pages. Based on this model, intrinsic relationships among pages could be revealed, and in turn a web page community could be constructed. The issues that are related to the application of the model are deeply investigated and studied. The concepts of community and intrinsic relationships, as well as the proposed matrix-based model, are then extended to other application areas such as biological data processing. Some application cases of the model in a broad range of areas are presented, demonstrating the potentials of this matrix-based model.