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1 In a retrospective study, we stratified 79 patients with paracetamol hepatotoxicity into two groups according to weekly alcohol consumption below ( n = 49) or above ( n = 30) Royal College of Physicians' guidelines of 21 units week -1 for males and 14 for females. 2 Survival was lower (33%) and serum creatinine on admission higher (median 207 μmol) in patients whose alcohol consumption was above recommended guidelines than in those whose drank less than this (65.9% and 138 μmol, P < 0.01 and P = 0.027, respectively). An arterial blood pH < 7.30 on admission was also more common in those patients with a higher alcohol consumption (30% v 12.2%, P = 0.05). 3 In all patients whose alcohol consumption exceeded the guidelines, paracetamol overdose was fatal if associated with a serum creatinine greater than 300 μmol in conjunction with a prothrombin time over 100 s and grade 3 or 4 encephalopathy or a peak prothrombin time over 180 s. 4 Chronic alcohol intake above suggested limits is an adverse prognostic feature in cases of severe paracetamol overdose. This effect is partly related to increased nephrotoxicity.

The drainage of a viscous gravity current into a deep porous medium driven by both the gravitational and capillary forces is considered in two steps. We first study the one-dimensional case where a layer of fluid drains vertically into an infinitely deep porous medium. We determine a transition from the capillary-driven regime to the gravity-driven regime as time proceeds. Second, we solve the coupled spreading and drainage problem. There are no self-similar solutions of the problem for the entire time period, so asymptotic analyses are developed for the height, depth and front location in both the early-time and the late-time periods. In addition, we present numerical results of the governing partial differential equations, which agree well with the self-similar solutions in the appropriate asymptotic limits.

This paper gives a introduction of a SMES unit using 2G HTS wires. A complete SMES system including both superconducting coils and control circuit has been designed to operate at 77 K. Three single-phase H-bridge converters have been used in the control circuit. A loop control signal is sent out by using 32 fixed point Digital Signal Processor (DSP). The complete circuit has been both modelled in simulation and built experimentally. The results validate that this SMES successfully compensates a voltage sag in a power system.

A new correlation has been developped for predicting the wall film thickness in risers operating in the fast fluidisation regime. The correlation has been developed from published solids flux and particle velocity measurements made in circulating fluidised-bed risers.

AbstractDetermining the implications of global climate change for highly mobile taxa such as migratory birds requires a perspective that is spatiotemporally comprehensive and ecologically relevant. Here, we document how passerine bird species that migrate within the Western Hemisphere (n = 77) are associated with projected novel climates across the full annual cycle. Following expectations, highly novel climates occurred on tropical non‐breeding grounds and the least novel climates occurred on temperate breeding grounds. Contrary to expectations, highly novel climates also occurred within temperate regions during the transition from breeding to autumn migration. This outcome was caused by lower inter‐annual climatic variability occurring in combination with stronger warming projections. Thus, migrants are projected to encounter novel climates across the majority of their annual cycle, with a pronounced peak occurring when juveniles are leaving the nest and preparing to embark on their first migratory journey, which may adversely affect their chances of survival.

Abstract The ac impedance method has been used to investigate the conductivity of pressed HUP pellets. The activation energy for the ionic conduction process at high frequencies (30 kJ mol −1 ) was attributed to a simple proton hopping step. At lower frequencies (32 Hz) a Warburg diffusional impedance was observed with a much higher activation energy. This was attributed to the higher energy process of vacancy rotations needed for ion transfer over significant distances. Using a concentration cell, with HUP as the electrolyte, the thermodynamics of the hydrogen-tungsten oxide system was investigated.

Nuclear power generation offers a reliable, low-impact and large-scale alternative to fossil fuels. However, concerns exist over the safety and sustainability of this method of power production, and it remains unpopular with some governments and pressure groups throughout the world. Fast thorium fuelled accelerator-driven sub-critical reactors (ADSRs) offer a possible route to providing further re-assurance regarding these concerns on account of their properties of enhanced safety through sub-critical operation combined with reduced actinide waste production from the thorium fuel source. The appropriate sub-critical margin at which these reactors should operate is the subject of continued debate. Commercial interests favour a small sub-critical margin in order to minimise the size of the accelerator needed for a given power output, whilst enhanced safety would be better satisfied through larger sub-critical margins to further minimise the possibility of a criticality excursion. Against this background, this paper examines some of the issues affecting reactor safety inherent within thorium fuel sources resulting from the essential Th90232→Th90233→Pa91233→U92233 breeding chain. Differences in the decay half-lives and fission and capture cross-sections of 233Pa and 233U can result in significant changes in the reactivity of the fuel following changes in the reactor power. Reactor operation is represented using a homogeneous lumped fast reactor model that can simulate the evolution of actinides and reactivity variations to first-order accuracy. The reactivity of the fuel is shown to increase significantly following a loss of power to the accelerator. Where the sub-critical operating margins are small this can result in a criticality excursion unless some form of additional intervention is made, for example through the insertion of control rods.

Abstract The choice of turbulence model can have a strong impact on results for many turbomachinery zones. Palliative corrections to them and also transition modeling can have a further profound solution impact. The spectral gaps necessary for theoretically valid URANS solutions are also lacking in certain turbomachinery zones. Large Eddy Simulation (LES) alleviates the serious area of turbulence modeling uncertainty but with an extreme increase in computational cost. However, there seems a lack of validation data to explore in depth the performance of LES and thus strategies to refine it. LES best practices are needed. Although LES is, obviously, much less model dependent than RANS, grids currently used for more practical simulations are clearly insufficiently fine for the LES model and numerical schemes not to be playing an excessively strong role. Very few turbomachinery simulations make use of properly constructed, correlated turbulence inflow. Even if this is attempted, most measurement sets are incomplete and lack an adequate basis for modeling this inflow. Gas turbines are highly complex coupled systems and hence inflow and outflow boundary condition specification needs to go beyond just synthesizing turbulent structures and preventing their reflection. Despite the strong limitations of the dissipative Smagorinsky model, it still sees the most wide spread use, generally, in excessively dissipative flow solvers. Monotone Integrated LES (MILES) related approaches, hybrid LES–RANS and more advanced LES models seem to have an equal but subservient frequency of use in turbomachinery applications. Clearly the introduction of a RANS layer can have a substantial accuracy penalty. However, it does allow LES to be rationally used, albeit in a diluted sense for industrial applications. The Reynolds numbers found in turbomachinery are substantial. However, in certain areas evidence suggests they will not be enough to ensure a long inertial subrange and hence the use of standard LES modeling practices. Despite the excessively coarse grids used in much of the LES work reviewed, with essentially RANS based codes, meaningful results are often gained. This can perhaps be attributed to the choice of cases, these being ones for which RANS modeling gives extremely poor performance. It is a concern that for practical turbomachinery LES studies grid densities used tend to have an Reynolds number scaling to a strong negative power.

Abstract This paper addresses three questions that are relevant to integrating different regional transmission areas. Market integration normally increases the number of competitors and should therefore reduce prices but the first section shows that prices could rise when the number of generator s initially increases. Regulatory effort will also be affected by market integration. If the number of generators in either market is low, then our analysis suggests that the outcome depends on whether the regulators act independently or coordinate. Finally, if markets are gradually combined into larger units, the choice of transmission allocation (coordinated auctions or market coupling) will affect the prospects of making further gains and hence could lead to incomplete reform.

Abstract The paper considers the normal impact of elastic-perfectly plastic spheres, with and without interface adhesion, and presents an analytical solution for the coefficient of restitution which is expressed in terms of the impact velocity, the critical sticking velocity and the velocity below which the interaction is assumed to be elastic.