Are point of management assays relevant for food safety in the poultry industries?

The current pandemic has ensured considerable attention has been paid to the role of the approach termed ‘Point of Care’ diagnostics. Indeed, the term ‘RAT’ (Rapid Antigen Test) and RAT hunting now have totally different meaning to that widely understood before 2020. In the veterinary field, including food safety, the term used for these types of rapid in situ assays is ‘Point of Management’ (POM) assays. In this article, we describe our recent research on low cost, low technology, in-house style POM assays in the field of food safety as applied to the poultry industries. We then discuss what are the advantages and disadvantages of these low cost, low technology POM assays

Population and Virulence Factor Analysis of Staphylococcus aureus from Bovine Mastitis.

End of Project ReportsStaphylococcus aureus is a major cause of bovine mastitis and the disease is responsible for substantial economic losses in the dairy industry world-wide. A large number of commonly accepted virulence factors are associated with S. aureus but it is yet to be elucidated which of these are important for infection of the bovine udder. A rational and effective strategy for the control of intramammary infections may need to be directed against clones of S. aureus that commonly cause disease. The objective of this study was to characterise the genetic variance of S. aureus isolate populations from infected udders in Ireland using RAPD-PCR, ribotyping and multilocus enzyme electrophoresis (MLEE). Similar S. aureus isolates collected in the USA were also typed in order to compare strain differences in staphylococcal populations in a different environment. Phenotypic diversity based on a number of presumed virulence factors together with antibiotic sensitivity was examined and correlations between phenotype and genotype were identified, if present. In addition, a pathogenicity island encoding multiple superantigens was completely sequenced and characterised. Knockout mutants of these superantigens were also constructed and in vitro functional analysis performed. Laboratory animal experiments (mice and rabbits) were used to study the relative pathogenicity of individual staphylococcal strains (mice) and also to measure the immunological responses after prolonged exposure to the predominant strains (rabbits)

Classical symmetric functions in superspace

We present the basic elements of a generalization of symmetric function theory involving functions of commuting and anticommuting (Grassmannian) variables. These new functions, called symmetric functions in superspace, are invariant under the diagonal action of the symmetric group on the sets of commuting and anticommuting variables. In this work, we present the superspace extension of the classical bases, namely, the monomial symmetric functions, the elementary symmetric functions, the completely symmetric functions, and the power sums. Various basic results, such as the generating functions for the multiplicative bases, Cauchy formulas, involution operations as well as the combinatorial scalar product are also generalized.Comment: 21 pages, this supersedes the first part of math.CO/041230

Be different to be better: the effect of personality on optimal foraging with incomplete knowledge

Many animal populations include a diversity of personalities, and these personalities are often linked to foraging strategy. However, it is not always clear why populations should evolve to have this diversity. Indeed, optimal foraging theory typically seeks out a single optimal strategy for individuals in a population. So why do we, in fact, see a variety of strategies existing in a single population? Here, we aim to provide insight into this conundrum by modelling the particular case of foraging seabirds, that forage on patchy prey. These seabirds have only partial knowledge of their environment: they do not know exactly where the next patch will emerge, but they may have some understanding of which locations are more likely to lead to patch emergence than others. Many existing optimal foraging studies assume either complete knowledge (e.g. Marginal Value Theorem) or no knowledge (e.g. Lévy Flight Hypothesis), but here we construct a new modelling approach which incorporates partial knowledge. In our model, different foraging strategies are favoured by different birds along the bold-shy personality continuum, so we can assess the optimality of a personality type. We show that it is optimal to be shy (resp. bold) when living in a population of bold (resp. shy) birds. This observation gives a plausible mechanism behind the emergence of diverse personalities. We also show that environmental degradation is likely to favour shyer birds and cause a decrease in diversity of personality over time

The Link vs. the Event: Activating and Deactivating Elements in Time-Based Hypermedia

Activation and deactivation of media items plays a fundamental role in the playing of multimedia and time-based hypermedia presentations. Activation and deactivation information thus has to be captured in an underlying document format. In this paper we show that a number of aspects of activation and deactivation information can be captured using both link structures and events in time-based hypermedia. In particular, we discuss how deactivation and activation can be specified, how the activations and deactivations can be initiated and potential (synchronization) relationships between the elements involved. We first introduce the notions of time-based scheduling and event-based scheduling and then present a short summary of linking. We discuss the similarities between event-based scheduling and linking. We describe a number of aspects of activation and deactivation that can be specified within a document. We then discuss how activation and deactivation information can be recorded in link structures and events

Multi-band material loaded Low-SAR antenna for mobile handsets

Previous studies have shown that monopoles loaded with material of equal permittivity and permeability values give increased bandwidth and radiation efficiency for a given size reduction. Positioning the monopole orthogonally to the head directs pattern nulls towards the head, which leads to low Specific Absorption Rates (SAR). Simulated results of the material loaded monopole showed dual-mode behaviour. In this paper, the simple monopole is translated into a compact antenna design suitable for mobile handsets. Metallic strips are printed on the material block to increase the number of modes and realise a small, quad-band, low-SAR handset antenna

Investigation into the realisation of a low-SAR, dual mode material coated antenna for mobile handsets

Previous theoretical and experimental work on material loaded antennas illustrated that choosing a material mix containing equal permittivity and permeability in combination with specific positioning of the antenna in relation to the head can produce the definitive small size, high efficiency, low specific absorption rate (SAR) antenna. Further results obtained from a TLM simulator indicate the antenna's ability to operate in wideband dual mode and provide design guidelines for its realisation. New materials are tested and design-engineering techniques are explored, towards the ultimate aim of realising and integrating the antenna into the handset

Feasibility of a triple mode, low SAR material coated antenna for mobile handsets

It has been previously established that material loaded monopoles having equal permittivity and permeability values, give increased bandwidth and radiation efficiency for a given size reduction. Very low Specific Absorption Rates (SAR) have been obtained by orthogonally positioning the antenna towards the head. Recent results obtained from a TLM simulator indicate the antenna’s capability to operate in dual mode. In this present paper various designs are researched, in order to preserve and translate the antenna features into a more compact embedded version. A final design solution is presented with the addition of metal strips, confirming the realisation of a small, triple-band, low-SAR handset antenna

Macdonald polynomials in superspace: conjectural definition and positivity conjectures

We introduce a conjectural construction for an extension to superspace of the Macdonald polynomials. The construction, which depends on certain orthogonality and triangularity relations, is tested for high degrees. We conjecture a simple form for the norm of the Macdonald polynomials in superspace, and a rather non-trivial expression for their evaluation. We study the limiting cases q=0 and q=\infty, which lead to two families of Hall-Littlewood polynomials in superspace. We also find that the Macdonald polynomials in superspace evaluated at q=t=0 or q=t=\infty seem to generalize naturally the Schur functions. In particular, their expansion coefficients in the corresponding Hall-Littlewood bases appear to be polynomials in t with nonnegative integer coefficients. More strikingly, we formulate a generalization of the Macdonald positivity conjecture to superspace: the expansion coefficients of the Macdonald superpolynomials expanded into a modified version of the Schur superpolynomial basis (the q=t=0 family) are polynomials in q and t with nonnegative integer coefficients.Comment: 18 page

Professor Jim James ... a great researcher and motivator in the field of antennas

This paper is dedicated to Professor Jim James. It is a celebration of his life, career and world renowned research contribution to the engineering community. Jim was eminent for his pioneering research contributions to the fundamental understanding of radiation mechanisms in printed patch and small antennas including seminal achievements, both theoretical and in terms of demonstrated practical applications, in communications, radar and medical electronics. The paper includes a brief summary of his research. Details will also be included on some of his latest work involving low SAR material coated mobile handset antennas