Key derivation function : the SCKDF scheme

A key derivation function is used to generate one or more cryptographic keys from a private (secret) input value. This paper proposes a new method for constructing a generic stream cipher based key derivation function. We show that our proposed key derivation function based on stream ciphers is secure if the underlying stream cipher is secure. We simulate instances of this stream cipher based key derivation function using three eStream finalist: Trivium, Sosemanuk and Rabbit. The simulation results show these stream cipher based key derivation functions offer efficiency advantages over the more commonly used key derivation functions based on block ciphers and hash functions.

A nonlinear position controller for maritime operations of Rotary-wing UAVs

This paper presents a disturbance attenuation controller for horizontal position stabilization for hover and automatic landings of a Rotary-wing Unmanned Aerial Vehicle (RUAV) operating in rough seas. Based on a helicopter model representing aerodynamics during the landing phase, a nonlinear state feedback H-infinity controller is designed to achieve rapid horizontal position tracking in a gusty environment. The resultant control variables are further treated in consideration of practical constraints (flapping dynamics, servo dynamics and time lag effect) for implementation purpose. The high-fidelity closed-loop simulation using parameters of the Vario helicopter verifies performance of the proposed position controller. It not only increases the disturbance attenuation capability of the RUAV, but also enables rapid position response when gusts occur. Comparative studies show that the H-infinity controller exhibits great performance improvement and can be applied to ship/RUAV landing systems.

Ageing, technology anxiety and intuitive use of complex interfaces

This paper presents the outcome of a study that investigated the relationships between technology prior experience, self-efficacy, technology anxiety, complexity of interface (nested versus flat) and intuitive use in older people. The findings show that, as expected, older people took less time to complete the task on the interface that used a flat structure when compared to the interface that used a complex nested structure. All age groups also used the flat interface more intuitively. However, contrary to what was hypothesised, older age groups did better under anxious conditions. Interestingly, older participants did not make significantly more errors compared with younger age groups on either interface structures.

Nursing communication and casualisation of the nursing workforce.

Nurse researchers in Queensland •will undertake an ethnographic study of a health care facUity in order to explore the relationship between the increasing casualisation of the nursing workforce and the communication needs of full time and casual nurses.

The Law of Real Property Mortgages [2nd. Ed.]

This book examines the principles and practice of real estate mortgages in an easily accessible text referenced to all the Australian States. It specifically deals with the major theoretical and practical aspects of the land mortgage, including vitiating factors in formation, mortgagees’ powers and duties and mortgagors’ rights – both statutory and other – as well as assignment, insurance and discharge. It focuses exclusively on real estate mortgages and provides a thorough account of the law through analysis of the plethora of court decisions and statutory provisions in this area. Duncan and Dixon analyse the substance of the mortgage transaction from creation through to rights of enforcement. In its detailed consideration of the rights and obligations of mortgagors and mortgagees, it covers topics such as priorities and tacking, insurance, variation and assignment, rights of discharge, entry into possession, foreclosure and power of sale. In addition, the book contains a separate chapter on factors that may affect the validity and enforcement of a mortgage, together with separate consideration of a mortgagee’s right to enforce a guarantee provided on behalf of a mortgagor, and the rights and liabilities associated with a receivership regime initiated by

The roles of plant dsRNA-binding proteins in RNAi-like pathways

Dicers are associated with double-stranded RNA-binding proteins (dsRBPs) in animals. In the plant, Arabidopsis, there are four dicer-like (DCL) proteins and five potential dsRBPs. These DCLs act redundantly and hierarchically. However, we show there is little or no redundancy or hierarchy amongst the DRBs in their DCL interactions. DCL1 operates exclusively with DRB1 to produce micro (mi)RNAs, DCL4 operates exclusively with DRB4 to produce trans-acting (ta) siRNAs and 21nt siRNAs from viral RNA. DCL2 and DCL3 produce viral siRNAs without requiring assistance from any dsRBP. DRB2, DRB3 and DRB5 appear unnecessary for mi-, tasi-, viral si-, or heterochromatinising siRNA production but act redundantly in a developmental pathway. © 2008 Federation of European Biochemical Societies.

Cloning and characterization of microRNAs from Brassica napus

A library containing approximately 40,000 small RNA sequences was constructed for Brassica napus. Analysis of 3025 sequences obtained from this library resulted in the identification of 11 conserved miRNA families, which were validated by secondary structure prediction using surrounding sequences in the Brassica genome. Two 21 nt small RNA sequences reside within the arm of a pre-miRNA like stem-loop structure, making them likely candidates for novel non-conserved miRNAs in B. napus. Most of the conserved miRNAs were expressed at similar levels in a F1 hybrid B. napus line and its four double haploid progeny that showed marked variations in phenotypes, but many were differentially expressed between B. napus and Arabidopsis. The miR169 family was expressed at high levels in young leaves and stems, but was undetectable in roots and mature leaves, suggesting that miR169 expression is developmentally regulated in B. napus. © 2007 Federation of European Biochemical Societies.

The evolution and diversification of Dicers in plants

Most multicellular organisms regulate developmental transitions by microRNAs, which are generated by an enzyme, Dicer. Insects and fungi have two Dicer-like genes, and many animals have only one, yet the plant, Arabidopsis, has four. Examining the poplar and rice genomes revealed that they contain five and six Dicer-like genes, respectively. Analysis of these genes suggests that plants require a basic set of four Dicer types which were present before the divergence of mono- and dicotyledonous plants (∼200 million years ago), but after the divergence of plants from green algae. A fifth type of Dicer seems to have evolved in monocots. © 2006 Federation of European Biochemical Societies.

RNA silencing platforms in plants

Since the discovery of RNAi, its mechanism in plants and animals has been intensively studied, widely exploited as a research tool, and used for a number of potential commercial applications. In this article, we discuss the platforms for delivering RNAi in plants. We provide a brief background to these platforms and concentrate on discussing the more recent advances, comparing the RNAi technologies used in plants with those used in animals, and trying to predict the ways in which RNAi technologies may further develop. © 2005 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Treaty talk : past, present and future -- [Edited version of the inaugural Ngunnawal Lecture at the University of Canberra]

WELL I HEARD it on the radio and I saw it on the television. John Howard said there would be no talk of a treaty between his government and Indigenous people. He is not the first government leader to hold such views. Let me consider some of the public and official conversations that the concept of a treaty has invoked and what they reveal about white sovereignty. My interest in such dialogues stems from the fact that the idea of a treaty between white Australia and Indigenous people is not new and in the year of the centenary of Federation the Australian nation is still having trouble discussing it. Australian culture is less white than it used to be, but Anglicised whiteness forms the centre where white men established and defend institutions encouraging a possessive investment in white sovereignty. My intention is to invoke critical thought about these conversations. White sovereignty is a subject that asserts its dominance on social, political...