Acute renal failure (ARF) can complicate up to 60% of orthotopic liver transplants (OLT). The RIFLE criteria were developed to provide a consensus definition for acute renal disease in critically ill patients. Using the RI-FLE criteria, we aimed to determine the incidence and risk factors for ARF and acute renal injury (ARI), and to evaluate the link with the outcomes, patient survival and length of hospital stay. Three hundred patients, who received 359 OLTs, were retrospectively analyzed. ARI and ARF occurred post 11.1 and 25.7% of OLTs, respectively. By multivariate analysis, ARI was associated with pre-OLT hypertension and alcoholic liver disease and ARF with higher pre-OLT creatinine, inotrope and aminoglycoside use. ARF, but not ARI, had an impact on 30-day and 1-year patient survival and longer length of hospital stay. ARI and ARF, as defined by the RIFLE criteria, are common complications of OLT, with distinct risk factors and ARF has serious clinical consequences. The development of a consensus definition is a welcome advance, however these criteria do need to be validated in large studies in a wide variety of patient populations.

The future electricity network has to be able to manage energy coming from different grids as well as from Renewable Energy Sources (RES) and other Distributed Generation (DG) systems. Advanced power electronic converters can provide the means to control power flow and ensure proper and secure operation of future networks. This paper presents analysis, design and experimental validation of a back-to-back three-phase AC-DC-AC multi-level converter employed for Universal and Flexible Power Management (UNIFLEX-PM) of future electrical grids and its advanced control technique. The proposed system has been successfully tested for bidirectional power flow operation with different grid operating conditions such as voltage unbalance, frequency variation, harmonic distortion and faults due to short circuits

A device for measuring human breath ammonia was developed based on a single use, disposable, inkjet printed ammonia sensor fabricated using polyaniline nanoparticles. The device was optimized for sampling ammonia in human breath samples by addressing issues such as variations in breath sample volume, flow rate, sources of oral ammonia, temperature and humidity. The resulting system was capable of measuring ammonia in breath from 40 to 2993 ppbv (r(2 )= 0.99, n = 3) as correlated with photoacoustic laser spectroscopy and correlation in normal human breath samples yielded a slope of 0.93 and a Pearson correlation coefficient of 0.9705 (p < 0.05, n = 11). Measurement of ammonia in the breath of patients with end-stage kidney disease demonstrated its significant reduction following dialysis, while also correlating well with blood urea nitrogen (BUN) (r = 0.61, p < 0.01, n = 96). Excellent intraindividual correlations were demonstrated between breath ammonia and BUN (0.86 to 0.96), which demonstrates the possibility of using low cost point of care breath ammonia systems as a noninvasive means of monitoring kidney dysfunction and treatment.

Model predictive control (MPC) has a number of desirable attributes which are difficult to achieve with classical converter control techniques. Unfortunately, the nature of power electronics imposes restriction to the method, as a result of the limited number of available converter states. This, combined with the spread spectrum nature of harmonics inherent with the strategy, complicates further design. This paper presents a method for removing this characteristic without compromising the desirable functionality of predictive control. The method, named modulated MPC, is applied to a two-level three-phase converter and compared with a number of similar approaches. Experimental results are used to support theoretical analysis and simulation studies

Multilevel converters are known to have many advantages\ud for electricity network applications. In particular, cascaded\ud H-bridge converters are attractive because of their inherent\ud modularity and scalability. Predictive control for power converters\ud is advantageous as a result of its applicability to discrete system\ud and fast response. In this paper, a novel control technique, named\ud modulated model predictive control, is introduced with the aim\ud to increase the performance of model predictive control. The\ud proposed controller addresses a modulation scheme as part of the\ud minimization process. The proposed control technique is described\ud in detail, validated through simulation and experimental testing,\ud and compared with dead-beat and traditional model predictive\ud control. The results show the increased performance of the modulated\ud model predictive control with respect to the classic finite\ud control set model predictive control in terms of current waveform\ud total harmonic distortion (THD). Moreover, the proposed controller\ud allows a multi-objective control, with respect to dead-beat\ud control that does not present this capabilit

We carried out a retrospective review of 47 intra-articular fractures of the calcaneum treated by open reduction and internal fixation in 45 patients by a single surgeon between 1993 and 2001. The fractures were evaluated before operation by plain radiographs and a CT scan using Sanders' classification. Osteosynthesis involved a lateral approach and the use of the AO calcaneal plate. The mean follow-up was for ten years (7 to 15). Clinical assessment included the American Orthopaedic Foot and Ankle Society Score (AOFAS), the Creighton-Nebraska Score, the Kerr, Prothero, Atkins Score and the SF-36 Health Questionnaire. The radiological evaluation consisted of lateral and axial views of the os calcis. Arthritic changes in the subtalar joint were assessed with an internal oblique view and were graded using the Morrey and Wiedeman scale. There were 18 excellent (38.3%), 17 good (36.2%), three fair (6.3%) and nine poor (19.2%) results. Five patients had a superficial wound infection and five others eventually had a subtalar arthrodesis because of continuing pain. Restoration of Böhler's angle was associated with a better outcome. The degree of arthritic change in the subtalar joint did not correlate with the outcome scores or Sanders' classification. Prompt osteosynthesis should be considered for intra-articular fractures of the calcaneum in order to restore the shape of the hindfoot and Böhler's angle.

A note on versions:The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the repository url above for details on accessing the published version and note that access may require a subscription.For more information, please contact eprints@nottingham.ac.uk Abstract-This letter presents a fault detection method for modular multilevel converters (MMC) which is capable of locating a faulty semiconductor switching device in the circuit. The proposed fault detection method is based on a sliding mode observer (SMO) and a switching model of a half-bridge, the approach taken is to conjecture the location of fault, modify the SMO accordingly and then compare the observed and measured states to verify, or otherwise, the assumption. This technique requires no additional measurement elements and can easily be implemented in a DSP or micro-controller. The operation and robustness of the fault detection technique are confirmed by simulation results for the fault condition of a semiconductor switching device appearing as an open-circuit.

Moderate CKD was very prevalent. We identified the risk factors for progression of CKD and also that severe CKD was associated with reduced patient survival.