Tractable Combinations of Global Constraints

We study the complexity of constraint satisfaction problems involving global constraints, i.e., special-purpose constraints provided by a solver and represented implicitly by a parametrised algorithm. Such constraints are widely used; indeed, they are one of the key reasons for the success of constraint programming in solving real-world problems. Previous work has focused on the development of efficient propagators for individual constraints. In this paper, we identify a new tractable class of constraint problems involving global constraints of unbounded arity. To do so, we combine structural restrictions with the observation that some important types of global constraint do not distinguish between large classes of equivalent solutions.Comment: To appear in proceedings of CP'13, LNCS 8124. arXiv admin note: text overlap with arXiv:1307.179

Some investigations into non passive listening

Our knowledge of the function of the auditory nervous system is based upon a wealth of data obtained, for the most part, in anaesthetised animals. More recently, it has been generally acknowledged that factors such as attention profoundly modulate the activity of sensory systems and this can take place at many levels of processing. Imaging studies, in particular, have revealed the greater activation of auditory areas and areas outside of sensory processing areas when attending to a stimulus. We present here a brief review of the consequences of such non-passive listening and go on to describe some of the experiments we are conducting to investigate them. In imaging studies, using fMRI, we can demonstrate the activation of attention networks that are non-specific to the sensory modality as well as greater and different activation of the areas of the supra-temporal plane that includes primary and secondary auditory areas. The profuse descending connections of the auditory system seem likely to be part of the mechanisms subserving attention to sound. These are generally thought to be largely inactivated by anaesthesia. However, we have been able to demonstrate that even in an anaesthetised preparation, removing the descending control from the cortex leads to quite profound changes in the temporal patterns of activation by sounds in thalamus and inferior colliculus. Some of these effects seem to be specific to the ear of stimulation and affect interaural processing. To bridge these observations we are developing an awake behaving preparation involving freely moving animals in which it will be possible to investigate the effects of consciousness (by contrasting awake and anaesthetized), passive and active listening

eXtended Color Cell Compression -- A Runtime-efficient Compression Scheme for Software Video

Multimedia applications require a compression and decompression scheme for digital video. The standardized and widely used techniques JPEG and MPEG provide very good compression ratios, but are computationally quite complex and demanding. We propose to use an extension to the much simpler Color Cell Compression scheme as an alternative. Our extension includes the use of variable block sizes, the reuse of color index values from previously encoded blocks, and Huffman encoding of the stream of blocks. We present experimental results showing that our scheme provides much better runtime performance than MPEG, at the cost of a slightly inferior compression ratio. It is thus especially suited for software videos in high-speed networks

The serum proteome of Atlantic salmon, Salmo salar, during pancreas disease (PD) following infection with salmonid alphavirus subtype 3 (SAV3)

Salmonid alphavirus is the aetological agent of pancreas disease (PD) in marine Atlantic salmon, Salmo salar, and rainbow trout, Oncorhynchus mykiss, with most outbreaks in Norway caused by SAV subtype 3 (SAV3). This atypical alphavirus is transmitted horizontally causing a significant economic impact on the aquaculture industry. This histopathological and proteomic study, using an established cohabitational experimental model, investigated the correlation between tissue damage during PD and a number of serum proteins associated with these pathologies in Atlantic salmon. The proteins were identified by two-dimensional electrophoresis, trypsin digest and peptide MS/MS fingerprinting. A number of humoral components of immunity which may act as biomarkers of the disease were also identified. For example, creatine kinase, enolase and malate dehydrogenase serum concentrations were shown to correlate with pathology during PD. In contrast, hemopexin, transferrin, and apolipoprotein, amongst others, altered during later stages of the disease and did not correlate with tissue pathologies. This approach has given new insight into not only PD but also fish disease as a whole, by characterisation of the protein response to infection, through pathological processes to tissue recovery. Biological significance: Salmonid alphavirus causes pancreas disease (PD) in Atlantic salmon, Salmo salar, and has a major economic impact on the aquaculture industry. A proteomic investigation of the change to the serum proteome during PD has been made with an established experimental model of the disease. Serum proteins were identified by two-dimensional electrophoresis, trypsin digest and peptide MS/MS fingerprinting with 72 protein spots being shown to alter significantly over the 12 week period of the infection. The concentrations of certain proteins in serum such as creatine kinase, enolase and malate dehydrogenase were shown to correlate with tissue pathology while other proteins such as hemopexin, transferrin, and apolipoprotein, altered in concentration during later stages of the disease and did not correlate with tissue pathologies. The protein response to infection may be used to monitor disease progression and enhance understanding of the pathology of PD

Opto-mechanical measurement of micro-trap via nonlinear cavity enhanced Raman scattering spectrum

High-gain resonant nonlinear Raman scattering on trapped cold atoms within a high-fineness ring optical cavity is simply explained under a nonlinear opto-mechanical mechanism, and a proposal using it to detect frequency of micro-trap on atom chip is presented. The enhancement of scattering spectrum is due to a coherent Raman conversion between two different cavity modes mediated by collective vibrations of atoms through nonlinear opto-mechanical couplings. The physical conditions of this technique are roughly estimated on Rubidium atoms, and a simple quantum analysis as well as a multi-body semiclassical simulation on this nonlinear Raman process is conducted.Comment: 7 pages, 2 figure

Towards a population of HMXB/NS microquasars as counterparts of low-latitude unidentified EGRET sources

The discovery of the microquasar LS 5039 well within the 95% conficence contour of the Unidentified EGRET Source (UES) 3EG J1824-1514 was a major step towards the possible association between microquasars (MQs) and UESs. The recent discovery of precessing relativistic radio jets in LS I +61 303, a source associated for long time with 2CG 135+01 and with the UES 3EG J0241+6103, has given further support to this idea. Finally, the very recently proposed association between the microquasar candidate AX J1639.0-4642 and the UES 3EG J1639-4702 points towards a population of High Mass X-ray Binary (HMXB)/Neutron Star (NS) microquasars as counterparts of low-latitude unidentified EGRET sources.Comment: 12 pages, 7 figures. Proceedings of the Conference "The Multiwavelength Approach to Unidentified Gamma-ray Sources", to appear in the journal Astrophysics and Space Scienc

Quantized spin waves in the metallic state of magnetoresistive manganites

High resolution spin waves measurements have been carried out in ferromagnetic (F) La(1-x)(Sr,Ca)xMnO3 with x(Sr)=0.15, 0.175, 0.2, 0.3 and x(Ca)=0.3. In all q-directions, close to the zone boundary, the spin wave spectra consist of several energy levels, with the same values in the metallic and the x\approx 1/8 ranges. Mainly the intensity varies, jumping from the lower energy levels determined in the x\approx 1/8 range to the higher energy ones observed in the metallic state. On the basis of a quantitative agreement found for x(Sr)=0.15 in a model of ordered 2D clusters, the spin wave anomalies of the metallic state can be interpreted in terms of quantized spin waves within the same 2D clusters, embedded in a 3D matrix.Comment: 4 pages, 5 figure

Exact eigenstate analysis of finite-frequency conductivity in graphene

We employ the exact eigenstate basis formalism to study electrical conductivity in graphene, in the presence of short-range diagonal disorder and inter-valley scattering. We find that for disorder strength, $W \ge$ 5, the density of states is flat. We, then, make connection, using the MRG approach, with the work of Abrahams \textit{et al.} and find a very good agreement for disorder strength, $W$ = 5. For low disorder strength, $W$ = 2, we plot the energy-resolved current matrix elements squared for different locations of the Fermi energy from the band centre. We find that the states close to the band centre are more extended and falls of nearly as $1/E_l^{2}$ as we move away from the band centre. Further studies of current matrix elements versus disorder strength suggests a cross-over from weakly localized to a very weakly localized system. We calculate conductivity using Kubo Greenwood formula and show that, for low disorder strength, conductivity is in a good qualitative agreement with the experiments, even for the on-site disorder. The intensity plots of the eigenstates also reveal clear signatures of puddle formation for very small carrier concentration. We also make comparison with square lattice and find that graphene is more easily localized when subject to disorder.Comment: 11 pages,15 figure

Professionalism, Golf Coaching and a Master of Science Degree: A commentary

As a point of reference I congratulate Simon Jenkins on tackling the issue of professionalism in coaching. As he points out coaching is not a profession, but this does not mean that coaching would not benefit from going through a professionalization process. As things stand I find that the stimulus article unpacks some critically important issues of professionalism, broadly within the context of golf coaching. However, I am not sure enough is made of understanding what professional (golf) coaching actually is nor how the development of a professional golf coach can be facilitated by a Master of Science Degree (M.Sc.). I will focus my commentary on these two issues

The health and educational costs of preterm birth to 18 years of age in Australia

Background: Preterm birth is the greatest cause of death up to five years of age and an im-portant contributor to lifelong disability. There is increasing evidence that a meaningful pro-portion of early births may be prevented, but widespread introduction of effective preventive strategies will require financial support.Aims: This study estimated the economic cost to the Australian government of preterm birth, up to 18 years of age.Materials and Methods: A decision-analytic model was developed to estimate the costs of preterm birth in Australia for a hypothetical cohort of 314 814 children, the number of live births in 2016. Costs to Australia’s eight jurisdictions included medical expenditures and ad-ditional costs to educational services.Results: The total cost of preterm birth to the Australian government associated with the an-nual cohort was estimated at $1.413 billion (95% CI 1047-1781). Two-thirds of the costs were borne by healthcare services during the newborn period and one-quarter of the costs by educational services providing special assistance. For each child, the costs were highest for those born at the earliest survivable gestational age, but the larger numbers of children born at later gestational ages contributed heavily to the overall economic burden.Conclusion: Preterm birth leaves many people with lifelong disabilities and generates a sig-nificant economic burden to society. The costs extend beyond those to the healthcare system and include additional educational needs. Assessments of economic costs should inform eco-nomic evaluations of interventions aimed at the prevention or treatment of preterm birth.John P. Newnham, Chris Schilling, Stavros Petrou, Jonathan M Morris, Euan M. Wallace, Kiarna Brown ... et al