Farming in the "New Economy" : An Australian Perspective

Barriers to trade between countries have reduced through the general Agreement on Tariffs and Trade (GATT) and the World Trade Organisation (WTO). The nature of trade between businesses is also changing dramatically through developments in Information Technology but also due to adoption of quality assurance and new approaches to supply chain management. The impacts of this "New Economy" vary around the world. This paper considers the implications of these developments for Australian farmers. Whilst these changes can be regarded as generally advantageous to Australian farmers, they may be disadvantaged in some areas because of the relatively small size of the Australian farming sector, its geographical dispersion, the advent of a range of new technologies and the structure of agribusinesses. The potential changes to the nature of farming and farm management skills are discussed.Farm Management,

Modern seawater acidification: The response of foraminifera to high-CO<inf>2</inf> conditions in the Mediterranean Sea

The seas around the island of Ischia (Italy) have a lowered pH as a result of volcanic gas vents that emit carbon dioxide from the sea floor at ambient seawater temperatures. These areas of acidified seawater provide natural laboratories in which to study the long-term biological response to rising CO2 levels. Benthic foraminifera (single-celled protists) are particularly interesting as they have short life histories, are environmentally sensitive and have an excellent fossil record. Here, we examine changes in foraminiferal assemblages along pH gradients at CO2 vents on the coast of Ischia and show that the foraminiferal distribution, diversity and nature of the fauna change markedly in the living assemblages as pH decreases. © 2010 Geological Society of London

Farm Management - Bugger the roots, where is the future?

The Farm Management discipline has long been closely aligned with agricultural economics. The question we raise is not where either discipline came from but where is Farm Management going. The impact of globalisation, the rising tide of deregulation and chain reversal mean that farm management professionals who have traditionally focused on optimisation of activities at a farm level are now commonly expected to use sociology and management science to explain economic organisation and performance on farms. They also are required to look at relationships in the value chain(s) in which the farm sits. This paper will analyse the implications of such change for Farm Management professionals.Farm Management, value chains, Farm Management,

Kinetics of acute hepatitis B virus infection in humans

Using patient data from a unique single source outbreak of hepatitis B virus (HBV) infection, we have characterized the kinetics of acute HBV infection by monitoring viral turnover in the serum during the late incubation and clinical phases of the disease in humans. HBV replicates rapidly with minimally estimated doubling times ranging between 2.2 and 5.8 d (mean 3.7 ± 1.5 d). After a peak viral load in serum of nearly 1010 HBV DNA copies/ml is attained, clearance of HBV DNA follows a two or three phase decay pattern with an initial rapid decline characterized by mean half-life (t1/2) of 3.7 ± 1.2 d, similar to the t1/2 observed in the noncytolytic clearance of covalently closed circular DNA for other hepadnaviruses. The final phase of virion clearance occurs at a variable rate (t1/2 of 4.8 to 284 d) and may relate to the rate of loss of infected hepatocytes. Free virus has a mean t1/2 of at most 1.2 ± 0.6 d. We estimate a peak HBV production rate of at least 1013 virions/day and a maximum production rate of an infected hepatocyte of 200–1,000 virions/day, on average. At this peak rate of virion production we estimate that every possible single and most double mutations would be created each day

Information hiding and retrieval in Rydberg wave packets using half-cycle pulses

We demonstrate an information hiding and retrieval scheme with the relative phases between states in a Rydberg wave packet acting as the bits of a data register. We use a terahertz half-cycle pulse (HCP) to transfer phase-encoded information from an optically accessible angular momentum manifold to another manifold which is not directly accessed by our laser pulses, effectively hiding the information from our optical interferometric measurement techniques. A subsequent HCP acting on these wave packets reintroduces the information back into the optically accessible data register manifold which can then be read out

Gene expression time delays & Turing pattern formation systems

The incorporation of time delays can greatly affect the behaviour of partial differential equations and dynamical systems. In addition, there is evidence that time delays in gene expression due to transcription and translation play an important role in the dynamics of cellular systems. In this paper, we investigate the effects of incorporating gene expression time delays into a one-dimensional putative reaction diffusion pattern formation mechanism on both stationary domains and domains with spatially uniform exponential growth. While oscillatory behaviour is rare, we find that the time taken to initiate and stabilise patterns increases dramatically as the time delay is increased. In addition, we observe that on rapidly growing domains the time delay can induce a failure of the Turing instability which cannot be predicted by a naive linear analysis of the underlying equations about the homogeneous steady state. The dramatic lag in the induction of patterning, or even its complete absence on occasions, highlights the importance of considering explicit gene expression time delays in models for cellular reaction diffusion patterning

Optimal path planning for nonholonomic robotics systems via parametric optimisation

Abstract. Motivated by the path planning problem for robotic systems this paper considers nonholonomic path planning on the Euclidean group of motions SE(n) which describes a rigid bodies path in n-dimensional Euclidean space. The problem is formulated as a constrained optimal kinematic control problem where the cost function to be minimised is a quadratic function of translational and angular velocity inputs. An application of the Maximum Principle of optimal control leads to a set of Hamiltonian vector field that define the necessary conditions for optimality and consequently the optimal velocity history of the trajectory. It is illustrated that the systems are always integrable when n = 2 and in some cases when n = 3. However, if they are not integrable in the most general form of the cost function they can be rendered integrable by considering special cases. This implies that it is possible to reduce the kinematic system to a class of curves defined analytically. If the optimal motions can be expressed analytically in closed form then the path planning problem is reduced to one of parameter optimisation where the parameters are optimised to match prescribed boundary conditions.This reduction procedure is illustrated for a simple wheeled robot with a sliding constraint and a conventional slender underwater vehicle whose velocity in the lateral directions are constrained due to viscous damping

Antecedents and performance consequences of international outsourcing

The outsourcing of intermediate products to international suppliers is believed to improve firm performance. We investigate this claim and test key dimensions of the decision to outsource internationally using survey data on 200 manufacturing firms located in the Netherlands. We find that most international outsourcing is intra-regional in nature. Furthermore international outsourcing is a consequence of a firm‟s ability to search and evaluate foreign suppliers, which is co-determined by its size, multinationality, and frequency of cross-border communications. Finally, no performance effects were observed for international or global outsourcing. We conclude international outsourcing is a balancing act between lower production costs abroad and lower transaction costs locally