Mathematical models for describing the shape of the in vitro unstretched human crystalline lens

We developed orthogonal least-squares techniques for fitting crystalline lens shapes, and used the bootstrap method to determine uncertainties associated with the estimated vertex radii of curvature and asphericities of five different models. Three existing models were investigated including one that uses two separate conics for the anterior and posterior surfaces, and two whole lens models based on a modulated hyperbolic cosine function and on a generalized conic function. Two new models were proposed including one that uses two interdependent conics and a polynomial based whole lens model. The models were used to describe the in vitro shape for a data set of twenty human lenses with ages 7–82 years. The two-conic-surface model (7 mm zone diameter) and the interdependent surfaces model had significantly lower merit functions than the other three models for the data set, indicating that most likely they can describe human lens shape over a wide age range better than the other models (although with the two-conic-surfaces model being unable to describe the lens equatorial region). Considerable differences were found between some models regarding estimates of radii of curvature and surface asphericities. The hyperbolic cosine model and the new polynomial based whole lens model had the best precision in determining the radii of curvature and surface asphericities across the five considered models. Most models found significant increase in anterior, but not posterior, radius of curvature with age. Most models found a wide scatter of asphericities, but with the asphericities usually being positive and not significantly related to age. As the interdependent surfaces model had lower merit function than three whole lens models, there is further scope to develop an accurate model of the complete shape of human lenses of all ages. The results highlight the continued difficulty in selecting an appropriate model for the crystalline lens shape.

A novel profluorescent dinitroxide for imaging polypropylene degradation

Free-radical processes underpin the thermo-oxidative degradation of polyolefins. Thus, to extend the lifetime of these polymers, stabilizers are generally added during processing to scavenge the free radicals formed as the polymer degrades. Nitroxide radical precursors, such as hindered amine stabilizers (HAS),1,2 are common polypropylene additives as the nitroxide moiety is a potent scavenger of polymer alkyl radicals (R¥). Oxidation of HAS by radicals formed during polypropylene degradation yields nitroxide radicals (RRNO¥), which rapidly trap the polymer degradation species to produce alkoxyamines, thus retarding oxidative polymer degradation. This increase in polymer stability is demonstrated by a lengthening of the “induction period” of the polymer (the time prior to a sharp rise in the oxidation of the polymer). Instrumental techniques such as chemiluminescence or infrared spectroscopy are somewhat limited in detecting changes in the polymer during the initial stages of degradation. Therefore, other methods for observing polymer degradation have been sought as the useful life of a polymer does not extend far beyond its “induction period”

Rejoinder to James Hamilton

Hamilton (2001) makes a number of comments on our paper (Harding and Pagan, 2002b). The objectives of this rejoinder are, firstly, to note the areas in which we agree; secondly, to define with greater clarity the areas in which we disagree; and, thirdly, to point to other papers, including a longer version of this response, where we have dealt with some of the issues that he raises. The core of our debate with him is whether one should use an algorithm with a specified set of rules for determining the turning points in economic activity or whether one should use a parametric model that features latent states. Hamilton begins his criticism by stating that there is a philosophical distinction between the two methods for dating cycles and concludes that the method we use “leaves vague and intuitive exactly what this algorithm is intended to measure”. Nothing is further from the truth. When seeking ways to decide on whether a turning point has occurred it is always useful to ask the question, what is a recession? Common usage suggests that it is a decline in the level of economic activity that lasts for some time. For this reason it has become standard to describe a recession as a decline in GDP that lasts for more than two quarters. Finding periods in which quarterly GDP declined for two periods is exactly what our approach does. What is vague about this?

A distributed denial of service testbed

The Denial of Service Testing Framework (dosTF) being developed as part of the joint India-Australia research project for ‘Protecting Critical Infrastructure from Denial of Service Attacks’ allows for the construction, monitoring and management of emulated Distributed Denial of Service attacks using modest hardware resources. The purpose of the testbed is to study the effectiveness of different DDoS mitigation strategies and to allow for the testing of defense appliances. Experiments are saved and edited in XML as abstract descriptions of an attack/defense strategy that is only mapped to real resources at run-time. It also provides a web-application portal interface that can start, stop and monitor an attack remotely. Rather than monitoring a service under attack indirectly, by observing traffic and general system parameters, monitoring of the target application is performed directly in real time via a customised SNMP agent.

James Street market, Brisbane : a subtropical retail case study

Climate change mitigation is driving demand for energy-efficient and environmentally conscious commercial buildings in Australia. In the Australian subtropics, high rainfall, warm weather and humidity present unique challenges and opportunities for the architects tasked with designing eco-sensitive projects. The case of the James Street Market in Brisbane’s Fortitude Valley shows that climate-responsive design is an effective approach for reducing the environmental impact of commercial developments. The James Street Market combines climate-responsiveness, environmentally sensitive design strategies and smart planning to create a more sustainable retail precinct. This paper details the design strategies featured in the James Street Market, the project that kicked off a renaissance in climate-responsive commercial building design in Brisbane.

Judge George W Paul's Japanese house : a case study

In the late 1880s a pre-fabricated Japanese house was shipped from Kobe, Japan, to Brisbane, Australia, and erected in the up-market suburb of New Farm by Japanese tradesmen. This paper is developed from a broader project researching the life of G W Paul, the man who had the house built and subsequently lived in it for the remainder of his life. Paul’s motivation in importing the house represented a unique, but unfulfilled effort to develop a future, hybrid culture for Queensland. This effort took the form of a commercial venture to construct Japanese houses as desirable and climatically suitable dwellings. Against the backdrop of this ambition, this paper presents new research to elucidate and extend previous knowledge, assesses the reception of the house by its nineteenth century Brisbane audience, and considers possible reasons for the limited response which signalled the cancellation of the commercial venture.

Selling James Bond : product placement in the James Bond films

The character of James Bond for many people is intrinsically linked in their minds with particular brands – Aston Martin, Bollinger, Omega, Smirnoff vodka, and so on. This direct association between character and brand highlights the intrinsic role of product placement in the film industry, and in the James Bond films in particular. Selling James Bond: Product Placement in the James Bond Films provides a comprehensive overview of the history of product placement in the James Bond series – charting the progression of the practice and drawing direct correlations to significant cultural and historical events that impacted upon the number and types of products incorporated into the series. While primarily a financial arrangement, it is also important that the practice of product placement be examined and understood in relation to these cultural contexts, an area of research so far largely ignored by academic study. Through extensive content analysis of the official James Bond film series, as well as utilising directors’ commentary and industry reports, this book illustrates the strong impact specific cultural and historical events have had on the practice of product placement in the series. In doing so, it provides an exciting and in-depth “behind the scenes” look at the James Bond film series, and its complicated and sometimes contentious history of product placement. In the process, it charts the gradual emergence of product placement from the more traditional background shot to becoming so embedded in the actual film narrative that they have become simply yet another method for filmmakers to produce cultural meaning.

Implementing a systematic process for rapidly embedding sustainability within chemical engineering education: a case study of James Cook University, Australia

Sustainability has emerged as a primary context for engineering education in the 21st Century, particularly the sub-discipline of chemical engineering. However, there is confusion over how to go about integrating sustainability knowledge and skills systemically within bachelor degrees. This paper addresses this challenge, using a case study of an Australian chemical engineering degree to highlight important practical considerations for embedding sustainability at the core of the curriculum. The paper begins with context for considering a systematic process for rapid curriculum renewal. The authors then summarise a 2-year federally funded project, which comprised piloting a model for rapid curriculum renewal led by the chemical engineering staff. Model elements contributing to the renewal of this engineering degree and described in this paper include: industry outreach; staff professional development; attribute identification and alignment; program mapping; and curriculum and teaching resource development. Personal reflections on the progress and process of rapid curriculum renewal in sustainability by the authors and participating engineering staff will be presented as a means to discuss and identify methodological improvements, as well as highlight barriers to project implementation. It is hoped that this paper will provide an example of a formalised methodology on which program reform and curriculum renewal for sustainability can be built upon in other higher education institutions.