Smooth transonic flow in an array of counter-rotating vortices

Numerical solutions to the steady two-dimensional compressible Euler equations corresponding to a compressible analogue of the Mallier & Maslowe (Phys. Fluids, vol. A 5, 1993, p. 1074) vortex are presented. The steady compressible Euler equations are derived for homentropic flow and solved using a spectral method. A solution branch is parameterized by the inverse of the sound speed at infinity, $c_{\infty}^{-1}$, and the mass flow rate between adjacent vortex cores of the corresponding incompressible solution, $\epsilon$. For certain values of the mass flux, the solution branches followed numerically were found to terminate at a finite value of $c_{\infty}^{-1}$. Along these branches numerical evidence for the existence of extensive regions of smooth steady transonic flow, with local Mach numbers as large as 1.276, is presented

Mild and facile synthesis of multi-functional RAFT chain transfer agents

In this paper we will describe the synthesis and characterization of a series of novel chain transfer agents for application in reversible addition fragmentation chain transfer polymerization (RAFT). The facile and mild conditions used for the synthesis of these new chain transfer agents should allow for the application of these methods for the preparation of a wide range of multifunctional chain transfer agent species. Some initial polymerization data for these multifunctional chain transfer agents is also reported

The control of Corynebacterium pseudotuberculosis infection in sheep flocks : a mathematical model of the impact of vaccination, serological testing, clinical examination and lancing of abscesses

A mathematical model of Corynebacterium pseudotuberculosis infection in sheep flocks was used to evaluate strategies for control and elimination of caseous lymphadenitis (CIA). Control strategies tested were vaccination, serological testing and removal of seropositives, clinical examination and removal of sheep with abscesses, lancing abscesses, and appropriate combinations. Three different infection rates with and without replacement of culled ewes were used to evaluate the control options. Controls were either implemented immediately after infection was detected in a flock or once CIA was at endemic equilibrium, and with different frequencies of examination or testing. Elimination of infection was defined as 99% confidence that no sheep were infected with C. pseudo tuberculosis. The control strategies were evaluated by estimating the reduction in infection or probability of elimination and the number of ewes culled from the flock. Lancing abscesses reduced the prevalence of infection when the initial prevalence was 0.90, but vaccination combined with clinical examination reduced infection rapidly with little impact on lamb productivity. Further research is required to develop a diagnostic test with at least 0.90 specificity and sensitivity under field conditions before any methods of control can be recommended with confidence

The key performance indicators of the BIM implementation process

Contemporarily some firms in the construction industry are attempting to adopt a BIM method of working. Each of these attempts reflects a varying BIM adoption philosophy and inevitably different BIM technologies, implementation strategies and roadmaps. On the other hand, all these attempts are often motivated to attain competitive advantages for product delivery in the market place. The question of what the best method of adopting BIM has not been answered yet. That is to say, it is required to identify a standard method that will benchmark the different BIM adoption cases by comparing the efficiency gains in these cases: a standard benchmarking method can help the stakeholders to decide on the most appropriate strategies for themselves. This paper explains the live experience of BIM adoption in a KTP (Knowledge Transfer Partnership) project, undertaken between the University of Salford and John McCall Architects practicing in the housing and regeneration fields, with a particular focus on a set of KPIs that have been developed and tested through the action research strategy in the project. Weighting of these KPI’s has been developed from an architectural business perspectiv

General practitioner deprivation payments in Northern Ireland: is the current system equitable?

The allocation of General practitioners deprivation payments has been a contentious issue since it was first proposed. This paper examines the method of allocation of such payments in Northern Ireland. A more equitable system would be based on enumeration districts, have a lower Jarman score and a closer relationship between Jarman score and remuneration. Unlike other parts of the UK these changes are now possible in Northern Ireland and should be implemented

Strategies for preparing fluorescently labelled polymer nanoparticles

There is great interest in the use of fluorescent polymer nanoparticles as optical imaging agents. When designing and synthesising a fluorescent polymer nanoparticle imaging agent there is a large variety in both the particle formation and dye attachment strategies that can be pursued. In this mini-review we detail this range of possibilities, illustrating with examples from the literature, and highlighting particular advantages in each case. © 2014 The Authors. Polymer International published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry

Efficient DNA-polymer coupling in organic solvents:a survey of amide coupling, Thiol-Ene and Tetrazine-Norbornene chemistries applied to conjugation of Poly(N-Isopropylacrylamide)

A range of chemistries were explored for the efficient covalent conjugation of DNA to poly(N-isopropylacrylamide) (poly(NIPAM)) in organic solvents. Amide coupling and thiol–ene Michael addition were found to be ineffective for the synthesis of the desired products. However, the inverse electron-demand Diels–Alder (DAinv) reaction between tetrazine (Tz) and norbornene (Nb) was found to give DNA–polymer conjugates in good yields (up to 40%) in organic solvents (N,N-dimethylformamide, N,N-dimethylacetamide and N-methyl-2-pyrrolidone), and without the need for a catalyst. Methods for the synthesis of Tz-and Nb- functionalised DNA were developed, along with a post-polymerisation functionalisation strategy for the production of Tz-functionalised polymers