Science, medicine, and the future. Prospecting for gold in the human genome

Doctors struggling with the daily problems of clinical medicine usually have little time for molecular and cell biology. But genetic research is producing an explosion of knowledge which doctors will need to understand in order to join in the ethical and financial debates that will inevitably follow the new treatments discovered. There may, indeed, be therapeutic gold hidden in our genes, but the price for it could be more than we can afford. This is the first of three articles introducing a series which aims to convey the excitement and potential power of biomedical science by speculating how current research will impinge on clinical management of common conditions

Molecular genetic approaches to understanding disease

Molecular genetics has greatly increased the understanding of diseases in which there is a single gene defect such as cystic fibrosis. Discovering the gene responsible and its function not only helps determine the pathogenesis of the disease but also offers a possible treatment-gene therapy. Polygenic disorders such as diabetes may soon yield their secrets to the same approach. Animal models of genetic diseases are proving useful research tools, and transgenesis has made xenografting possible. Furthermore, antisense technology allows specific inhibition of undesirably overexpressed genes such as those driving unwanted vascular cell proliferation and restenosis after angioplasty. The completion of the human genome project should make the search for "disease" gene much quicker and will increase still further the importance of these gene based approaches toward diseases

Comparative analysis of alternative fuels in detonation combustion

Detonation combustion prominently exhibits high thermodynamic efficiency which leads to better performance. As compared to the conventionally used isobaric heat addition in a Brayton cycle combustor, detonation uses a novel isochoric Humphrey cycle which utilises shocks and detonation waves to provide pressure-rise combustion. Such unsteady combustion has already been explored in wave rotor, pulse detonation engine and rotating detonation engine configurations as alternative technologies for the next generation of the aerospace propulsion systems. However, in addition to the better performance that the detonation mode of combustion offers, it is crucial to observe the environmental concerns as well. Therefore, this paper presents a one-dimensional numerical analysis for alternative fuels: Jet-A, Acetylene, Jatropha Bio-synthetic Paraffinic Kerosene, Camelina Bio-synthetic Paraffinic Kerosene, Algae Biofuel, and Microalgae Biofuel under detonation combustion conditions. For simplicity, the analysis is modelled using an open tube geometry. The analysis employs the Rankine-Hugoniot Equation, Rayleigh Line Equation, and Zel’dovich–von Neumann–Doering model and takes into account species mole, mass fraction, and enthalpies-of-formation of the reactants. Initially, minimum conditions for the detonation of each fuel are determined. Pressure, temperature, and density ratios at each stage of the combustion tube for different types of fuel are then explored systematically. Finally, the influence of different initial conditions is numerically examined to make a comparison for these fuels

A multifidelity multiobjective optimization framework for high-lift airfoils

High-lift devices design is a challenging task as it involves highly complex flow features while being critical for the overall performance of the aircraft. When part of an optimization loop, the computational cost of the Computational Fluid Dynamics becomes increasingly problematic. Methods to reduce the optimization time has been of major interest over the last 50 years. This paper presents a multiobjective multifidelity optimization framework that takes advantage of two approximation levels of the flow equations: a rapid method that provides quick estimates but of relatively low accuracy and a reference method that provides accurate estimations at the cost of a longer run-time. The method uses a sub-optimization, under a trust-region scheme, performed on the low-fidelity model corrected by a surrogate model that is fed by the high-fidelity tool. The size of the trust region is changed according to the accuracy of the corrected model. The multiobjective optimizer is used to set the positions of the ap and slat of a two-dimensional geometry with lift and drag as objectives with an empirical-based method and a Reynolds Averaged Navier-Stokes equations solver. The multifidelity method shows potential for discovering the complete Pareto front, yet it remains less optimal than the Pareto front from the high-fidelity-only optimization

Wall-resolved large eddy simulation over NACA0012 airfoil

The work presented here forms part of a project on Large-Eddy Simulation (LES) of aeroengine aeroacoustic interactions. In this paper we concentrate on LES of near-field flow over an isolated NACA0012 airfoil at zero angle of attack with Rec=2e5. The predicted unsteady pressure/velocity field is used in an analytically-based scheme for far-field trailing edge noise prediction. A wall resolved implicit LES or so-callednumerical Large Eddy Simulation (NLES) approach is employed to resolve streak-like structure in the near-wall flow regions. The mean and RMS velocity and pressure profile on airfoil surface and in wake are validated against experimental data and computational results from other researchers. The results of the wall-resolved NLES method are very encouraging. The effects of grid-refinement and higher-order numerical scheme on the wall-resolved NLES approach are also discussed

Electrical power grid network optimisation by evolutionary computing

A major factor in the consideration of an electrical power network of the scale of a national grid is the calculation of power flow and in particular, optimal power flow. This paper considers such a network, in which distributed generation is used, and examines how the network can be optimized, in terms of transmission line capacity, in order to obtain optimal or at least high-performing configurations, using multi-objective optimisation by evolutionary computing methods

Effects of biofuels properties on aircraft engine performance

Purpose-The purpose of this paper is to examine the effects of heat capacity and density of biofuels on aircraft engine performance indicated by thrust and fuel consumption. Design/methodology/approach-The influence of heat capacity and density was examined by simulating biofuels in a two-spool high-bypass turbofan engine running at cruise condition using a Cranfield in-house engine performance computer tool (PYTHIA). The effect of heat capacity and density on engine performance was evaluated through a comparison between kerosene and biofuels. Two types of biofuels were considered: Jatropha Bio-synthetic Paraffinic Kerosene (JSPK) and Camelina Bio-synthetic Paraffinic Kerosene (CSPK). Findings-Results show an increase in engine thrust and a reduction in fuel consumption as the percentage of biofuel in the kerosene/biofuel mixture increases. Besides a low heating value, an effect of heat capacity on increasing engine thrust and an effect of density on reducing engine fuel consumption are observed. Practical implications-The utilisation of biofuel in aircraft engines may result in reducing over-dependency on crude oil. Originality/value-This paper observes secondary factors (heat capacity and density) that may influence aircraft engine performance which should be taken into consideration when selecting new fuel for new engine designs

Regulation of glomerular cell number by apoptosis

Regulation of glomerular cell number by apoptosis. While commonly viewed as leading to glomerular scarring and end-stage renal failure, glomerular cell proliferation may be a beneficial response that promotes the injured glomerulus to return to its proper function. This brief review looks at the potentially counterbalancing influences that cause glomerular cells to survive, undergo mitosis, differentiate or die