Evolution of the SPS Power Converter Controls towards the LHC Era

By the end of the nineties, the power converter control system (Mugef) of the CERN proton accelerator (SPS) had undergone a complete modernization. This resulted in newly developed hardware for function generation, measurement and I/O in a VME environment, under the LynxOS real-time operating system. This has provided a platform on which extensions can be developed for future operation in the Large Hadron Collider (LHC) era. This paper describes some of these extensions, in particular a fast Surveillance and Interlock system for monitoring the power converter output currents. This will be mandatory for the safe operation of the SPS transfer lines TI2 & TI8 to LHC and for similar applications in the future. The strategies employed to cope with various failure modes of the power converters and the timely activation of the interlock are outlined. The new SPS controls infrastructure now under development, will give rise to new modes of operation for the Mugef systems. Integration with the proposed middleware must be undertaken in a structured evolution, while retaining compatibility with the current usage.Comment: Paper is 3 pages for ICAPEPCS 01 27 - 30 November 2001 San Jose. John C L Brazier is the principal author and a consultant to CERN (hence the CERN Email address but UK Organisation

The incidence of arthropathy adverse events in efalizumab-treated patients is low and similar to placebo and does not increase with long-term treatment: pooled analysis of data from Phase III clinical trials of efalizumab

A large-scale, pooled analysis of safety data from five Phase III clinical trials (including open-label extensions of two of these studies) and two Phase III open-label clinical trials of efalizumab was conducted to explore whether arthropathy adverse events (AEs) were associated with efalizumab treatment in patients with moderate-to-severe chronic plaque psoriasis. Data from patients who received subcutaneous injections of efalizumab or placebo were stratified for analysis into phases according to the nature and duration of treatment. These included: the ‘first treatment’ phase (0–12-week data from patients who received either efalizumab, 1 mg/kg once weekly, or placebo in the five placebo-controlled studies); the ‘extended treatment’ phase (13–24-week data from seven trials for all efalizumab-treated patients); and the ‘long-term treatment’ phase (data from efalizumab-treated patients who received treatment for up to 36 months in two long-term trials). Descriptive statistics were performed and the incidence of arthropathy AEs per patient-year was calculated using 95% confidence intervals (CIs). During the first treatment phase, a similar proportion of patients had an arthropathy AE in the efalizumab group (3.3%; 58/1740 patients) compared with the placebo group (3.5%; 34/979 patients); the incidence of arthropathy AEs per patient-year was 0.15 in the efalizumab group (95% CI 0.11–0.19) and 0.16 in the placebo group (95% CI 0.11–0.22). Analysis of first treatment phase data from one study (n = 793) showed that the incidence of psoriatic arthropathy per patient-year was lower in efalizumab-treated patients (0.10; 95% CI 0.05–0.18) than in those given placebo (0.17; 95% CI 0.08–0.30). During the extended treatment phase, the incidence of arthropathy remained low (0.17; 95% CI 0.14–0.22). Data from two long-term studies showed that there was no increase in the incidence of arthropathy AEs over time in patients treated with efalizumab for up to 36 months. Patients who had an arthropathy AE during treatment with efalizumab appeared to be more likely to have a history of arthropathy prior to treatment. Efalizumab does not appear to increase the risk of arthropathy AEs compared with placebo

Measurement of the transfer function of the main SPS Quadrupoles

During two short MD's we have measured the transfer function (amplitude and phase) of the main quadrupole string QD. By the word string we mean the global effect of power supplies, magnets and the eddy current effects of the vacuum chamber. This paper presents the measurement procedure and the results, which are needed for the design of a real-time feedback system for the betatron tunes ( Qloop)

Migration from WorldFIP to a Low-Cost Ethernet Fieldbus for Power Converter Control at CERN

Power converter control in the LHC uses embedded computers called Function Generator/Controllers (FGCs), which are connected to WorldFIP fieldbuses around the accelerator ring

Factors influencing long-term outcomes in relapsing-remitting multiple sclerosis: PRISMS-15

AIM: An exploratory study of the relationship between cumulative exposure to subcutaneous (sc) interferon (IFN) β-1a treatment and other possible prognostic factors with long-term clinical outcomes in relapsing–remitting multiple sclerosis (RRMS). METHODS: Patients in the original PRISMS study were invited to a single follow-up visit 15 years after initial randomisation (PRISMS-15). Outcomes over 15 years were compared in the lowest and highest quartile of the cumulative sc IFN β-1a dose groups, and according to total time receiving sc IFN β-1a as a continuous variable per 5 years of treatment. Potential prognostic factors for outcomes were analysed. RESULTS: Of 560 patients randomised in PRISMS, 291 returned for PRISMS-15 and 290 (51.8%) were analysed. Higher cumulative dose exposure and longer treatment time appeared to be associated with better outcomes on: annualised relapse rate, number of relapses, time to Expanded Disability Status Scale (EDSS) progression, change in EDSS, proportions of patients with EDSS ≥4 or ≥6, ≤5 relapses and EDSS <4 or <6, and time to conversion to secondary-progressive MS (SPMS). Higher dose exposure was associated with lower proportions of patients with EDSS progression and conversion to SPMS, and longer time on treatment with lower risk of first relapse. Change in EDSS from baseline to 24 months was a strong predictor of evaluated clinical outcomes over 15 years. CONCLUSIONS: These findings suggest that higher cumulative exposure to sc IFN β-1a may be associated with better clinical outcomes, and early change in EDSS score may have prognostic value, over many years, in RRMS