Quantum computing on encrypted data

The ability to perform computations on encrypted data is a powerful tool for protecting privacy. Recently, protocols to achieve this on classical computing systems have been found. Here we present an efficient solution to the quantum analogue of this problem that enables arbitrary quantum computations to be carried out on encrypted quantum data. We prove that an untrusted server can implement a universal set of quantum gates on encrypted quantum bits (qubits) without learning any information about the inputs, while the client, knowing the decryption key, can easily decrypt the results of the computation. We experimentally demonstrate, using single photons and linear optics, the encryption and decryption scheme on a set of gates sufficient for arbitrary quantum computations. Because our protocol requires few extra resources compared to other schemes it can be easily incorporated into the design of future quantum servers. These results will play a key role in enabling the development of secure distributed quantum systems

Scholarly Teaching Fellows: Drivers and (Early) Outcomes

In Australian universities, the majority of teaching is now delivered by casual academics, engaged on short-term, hourly-paid contracts. Casual and continuing academic staff have worked actively through the national tertiary education union to limit casualization, defend the ‘integrated’ academic model of research and teaching, and to improve pay and conditions for casual staff. Since 2012 the union has moved to proactively define new continuing positions for casual staff, as ‘Scholarly Teaching Fellows’, designed to provide job security for casual teaching academics. This paper uses data from a selected range of Enterprise Bargaining Agreements (EBAs) to explore whether this relaxation of the union’s traditional insistence on the teaching/research nexus is successfully reducing precarity while avoiding the further disaggregation of academic work and careers

Rotational 3D Printing of Sensor Devices using Reactive Ink Chemistries

This paper charts progress in three key areas of a project supported by both UK government and UK industry to manufacture novel sensor devices using rotary 3D printing technology and innovative ink chemistries; (1) the development of an STL file slicing algorithm that returns constant Z height 2D contour data at a resolution that matches the given print head setup, allowing digital images to be generated of the correct size without the need for scaling; (2) the development of image transformation algorithms which allow images to be printed at higher resolutions using tilted print heads and; (3) the formulation of multi part reaction inks which combine and react on the substrate to form solid material layers with a finite thickness. A Direct Light Projection (DLP) technique demonstrated the robustness of the slice data by constructing fine detailed three dimensional test pieces which were comparable to identical parts built in an identical way from slice data obtained using commercial software. Material systems currently under investigation include plaster, stiff polyamides and epoxy polymers and conductive metallic’s. Early experimental results show conductivities of silver approaching 1.42x105 Siemens/m.Mechanical Engineerin

Influence of adjunct use andcheese microenvironment on nonstarter lactic acid bacteria populations in Cheddar-type cheese

This study investigated population dynamics of starter, adjunct, and nonstarter lactic acid bacteria (NSLAB) in reduced-fat Cheddar and Colby cheese made with or without a Lactobacillus casei adjunct. Duplicate vats of cheese were manufactured and ripened at 7°C. Bacterial populations were monitored periodically by plate counts and by DNA fingerprinting of cheese isolates with the random amplified polymorphic DNA technique. Isolates that displayed a unique DNA fingerprint were identified to the species level by partial nucleotide sequence analysis of the 16S rRNA gene. Nonstarter biota in both cheese types changed over time, but populations in the Colby cheese showed a greater degree of species heterogeneity. The addition of the L. casei adjunct to cheese milk at 104 cfu/ml did not completely suppress “wild” NSLAB populations, but it did appear to reduce nonstarter species and strain diversity in Colby and young Cheddar cheese. Nonetheless, nonstarter populations in all 6-mo-old cheeses were dominated by wild L. casei. Interestingly, the dominant strains of L. casei in each 6-mo-old cheese appeared to be affected more by adjunct treatment and not cheese variety

Percolative shunting on electrified surface

The surface discharge of electrified dielectrics at high humidity is considered. The percolative nature of charge transport in electrets is established. Particular attention is given to the phenomena of adsorption and nucleation of electrically conducting phase in the cause of percolation cluster growth on electrified surface. The critical index of the correlation lenght for percolation cluster is found, and its value is in good agreement with the known theoretical estimations.Comment: 4 pages with 1 figure, revtex, published in Tech. Phys. Lett. 25 (1999) 877-879 with one additional figur

Directed Percolation and Generalized Friendly Walkers

We show that the problem of directed percolation on an arbitrary lattice is equivalent to the problem of m directed random walkers with rather general attractive interactions, when suitably continued to m=0. In 1+1 dimensions, this is dual to a model of interacting steps on a vicinal surface. A similar correspondence with interacting self-avoiding walks is constructed for isotropic percolation.Comment: 4 pages, 3 figures, to be published in Phys. Rev. Let

British research in accounting and finance (2001–2007): the 2008 research assessment exercise

No abstract available

Diabetic ketoacidosis presentations in a low socio-economic area: are services suitable?

Background:Diabetic ketoacidosis causes a significant number of hospitalisations worldwide, with rates tending to increase with remoteness and socioeconomic disadvantage. Our study aimed to explore healthcare professionals’ perceptions of factors affecting presentation of people with type 1 diabetes in a low socioeconomic area of Queensland, Australia. Methods: This was a qualitative study. Individual semi-structured face-to-face or telephone interviews were completed with patients with type 1 diabetes who had presented in diabetic ketoacidosis, and healthcare professionals who have experience in related care. Data were analysed using Gibbs’s framework of thematic analysis. Results: Four patients with type 1 diabetes and 18 healthcare professionals were interviewed. Restricted access was identified as a factor contributing to diabetic ketoacidosis and delayed presentation, with ketone testing supplies, continuous glucose monitoring technology and transport considered barriers. Many of these factors were arguably preventable. Opportunities to improve the care available to patients with type 1 diabetes were detailed, with particularly strong support for dedicated out of hours telephone help lines for adults with type 1 diabetes. Conclusions: Gaps in support for patient self-care to avoid diabetic ketoacidosis presentations and prevent late presentation of diabetic ketoacidosis revealed by this study require service reconfiguration to support care delivery. Until change is made, people with type 1 diabetes will continue to make both avoidable and delayed, acutely unwell, presentations to Emergency Department

Improving the economic value of photographic screening for optical coherence tomography-detectable macular oedema : a prospective, multicentre, UK study

Peer reviewedPublisher PD

Transport on Directed Percolation Clusters

We study random lattice networks consisting of resistor like and diode like bonds. For investigating the transport properties of these random resistor diode networks we introduce a field theoretic Hamiltonian amenable to renormalization group analysis. We focus on the average two-port resistance at the transition from the nonpercolating to the directed percolating phase and calculate the corresponding resistance exponent $\phi$ to two-loop order. Moreover, we determine the backbone dimension $D_B$ of directed percolation clusters to two-loop order. We obtain a scaling relation for $D_B$ that is in agreement with well known scaling arguments.Comment: 4 page