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Abstract Objectives To evaluate whether the projected 24% reduction in acute bed numbers in Lothian hospitals, which formed part of the private finance initiative (PFI) plans for the replacement Royal [...]

We aim to promote efficiency, to improve services and to stimulate fresh flows of investment. We want to harness the private sector's management expertise and resources, bringing a new approach [...]

Growing numbers of health authorities and NHS trusts are carrying out service 'reconfigurations' which involve the centralisation of services from two or more sites and the sale or downgrading of [...]

No light at the end of this tunnel? Lowering the cholesterol concentration undoubtedly reduces the prevalence of fatal and non-fatal myocardial infarction,[1] but three concerns remain. firstly, meta-analyses of both [...]

Further trials with harder end points are needed for all lipid lowering drugs Publication of the World Health Organisation trial of clofibrate (Atromid) reduced expectations that cholesterol lowering drugs might [...]

This paper proposes a control strategy for station keeping of an underwater vehicle- manipulator system when the manipulator is asked to perform a certain task. The control structure consists of an inverse dynamic feedforward controller, the interaction forces between subsystems and a PILIM feedback controller for pitch control of the vehicle. The UVMS includes a 6-DOF vehicle and a 3-link manipulator, where the manipulator has a significant mass compared to the vehicle. The equations of motion are based on a tree representation of the UVMS and are described with the Newton-Euler algorithm. Hydrodynamic effects and friction considerations are taken into account in the forward dynamic model, while in the inverse dynamic model they are ignored. Simulation results show the validity of the inverse dynamic model approach without perfect knowledge of the system for station keeping of the vehicle. A key contribution of the study is that it is based on a lightweight underwater system. The main problem addressed in this paper is the station keeping of an underwater vehicle when the attached manipulator is moving. It is demonstrated that an inverse dynamic model used as a feedforward controller is a viable solution in the presence of system uncertainties.

This paper presents a novel solution using a radial basis function network (RBFN) to approximate the inverse kinematics of a robotic system where the geometric parameters of the manipulator are unknown. Simulation and experimental results are presented for a three–link manipulator to demonstrate the effectiveness of the proposed approach. To achieve this level of performance, centres of hidden–layer units are regularly distributed in the workspace, constrained training data is used where inputs are collected approximately around the centre positions in the workspace and the training phase is performed using either strict interpolation or the least mean square algorithm. These proposed ideas have significantly improved the network's performance.

This paper proposes a new parameter estimation approach for a single-phase induction machine (SPIM) whose parameters are usually obtained using several traditional techniques such as the DC, no-load, load and locked-rotor tests. The proposal is based on using two advanced particle swarm optimisation (PSO) algorithms. In the PSO algorithm, the inertia weight, cognitive and social parameters and two independent random sequences are the main parameters which affect the search characteristics and convergence capability, as well as the solution quality in each application. Two advanced PSO algorithms, known as the dynamic particle swarm optimisation (dynamic PSO) and the chaos particle swarm optimisation (chaos PSO) algorithms modify the algorithm parameters to improve the performance of the standard PSO algorithm. The algorithms use the experimental measurements of the currents and active powers in the SPIM main and auxiliary windings as the inputs to the parameter estimator. The experimental results obtained compare the estimated SPIM parameters with the SPIM parameters achieved using the traditional tests. There is also a comparison of the solution quality between the standard PSO, dynamic PSO and chaos PSO algorithms. The results show that the dynamic PSO and chaos PSO algorithms are better than the standard PSO algorithm for parameter estimation of the SPIM.

This paper presents a novel dynamic model derivation for the PA10-6CE manipulator. The model consists of: gravity term based on manufacturer specifications, non-parametric friction term estimated experimentally, inertia, Coriolis and centrifugal terms computed based on simplified geometric link models and motor inertia estimated experimentally. The incorporation of the model terms is firstly analysed with a comparison of simulated and experimental closed-loop control tasks. Model-based controller performance is then evaluated and analysed in terms of complexity versus tracking error performance. The model-based controllers implemented are feedback linearisation, Slotine-Li and Wen-Bayard. Model-based controller performance is evaluated and analysed in terms of complexity versus tracking error performance.

Major depressive disorder (MDD) is a common heritable condition. The diversity of the phenotype coupled with aetiological and genetic heterogeneity present formidable obstacles in the search for causative genetic loci. Studies of large families with many affected individuals, and the selection of well‐defined clinical subgroups of depression, are two ways to reduce this complexity. Unexplained swelling symptoms (USS) are common in women and many patients give a strong personal and family history of depression. Co‐morbid depression and swelling symptoms define a useful sub‐phenotype for investigating genetic factors in depression. We have completed a genome‐wide linkage analysis using 371 microsatellite markers in four families where MDD is co‐morbid with USS. Of 47 affected individuals, 28 had both MDD and unexplained swelling, 11 had symptoms of swelling alone, and 8 had MDD alone. Parametric marker‐specific analysis identified one suggestive locus, D8S260 (LOD = 2.02) and non‐parametric multipoint variance component analysis identified a region on 7p (LOD = 2.10). A 47 cM suggestive linkage region on chromosome 14q (identified by both parametric and non‐parametric methods) was identified and investigated further with fine‐mapping markers but the evidence for linkage to this region decreased with increased marker information content. © 2007 Wiley‐Liss, Inc.

Manipulator movement produces force/moment disturbances which act on the underwater vehicle and alter its position, and consequently the manipulator end-effector position. The effect of the manipulator motion, assuming perfect manipulator joint angle tracking, on the vehicle's position and consequently the manipulator end-effector position is investigated assuming no vehicle control. Control of the vehicle's yaw angle, in this particular manipulator-vehicle configuration, has been determined to be the single most important factor in reducing the end-effector error variation. Due to the nonlinear dynamics of the vehicle, Slotine's sliding mode approach has been used. This technique allows the expressions developed for the manipulator disturbances to be incorporated in the control law. This is shown to be beneficial in the regulation of the vehicle's yaw angle, and offers improved performance compared with a sliding mode controller that does not incorporate the manipulator disturbances. This technique also demonstrates superior performance and insensitivity to parameter variations compared with a fixed-gain controller.

This paper presents an Internet remote control interface for a MITSUBISHI PA10-6CE manipulator established for the purpose of the ROBOT museum exhibition during spring and summer 2004. The robotic manipulator is a part of the Intelligent Robotic Systems Laboratory at Heriot – Watt University, which has been established to work on dynamic and kinematic aspects of manipulator control in the presence of environmental disturbances. The laboratory has been enriched by a simple vision system consisting of three web-cameras to broadcast the live images of the robots over the Internet. The Interface comprises of the TCP/IP server providing command parsing and execution using the open controller architecture of the manipulator and a client Java applet web-site providing a simple robot control interface.

Twenty-seven previously osteomalacic and 77 normal Asian women participated in a seven-day survey of dietary intake and daylight outdoor exposure. Individual levels of daylight outdoor exposure discriminated poorly between normal and osteomalacic women. The presence of osteomalacia was strongly related to varying degrees of vegetarianism. Lactovegetarianism (no meat, fish or egg consumption) was associated with significantly greater osteomalacic risk than ovolactovegetarianism (no meat or fish consumption). Unlike Asian rickets, high-extraction wheat cereal as chapatti was not a significant risk factor for osteomalacia in Asian women and dietary fibre was a less important risk factor than absent dietary meat, fish or egg. When exposure to ultraviolet radiation is limited, Asian osteomalacia (and Asian rickets) are determined by dietary factors.