Impulsive breakdown of mineral oil and natural and synthetic ester liquids when containing varying levels of moisture

This article reports and discusses the results of impulse breakdown study of different insulating liquids under highly divergent electric field conditions. Samples of a natural ester (Envirotemp FR3), a synthetic ester (MIDEL 7131), and a naphthenic mineral oil (Shell Diala S4 ZX) at different levels of relative humidity were exposed to HV impulses with a nominal 7-\mu \text{s} rise time and 150-kV peak voltage of both positive and negative polarity. A strong dependence of the breakdown voltage and time to breakdown of the investigated dielectric liquids was observed with respect to the polarity of the applied HV impulses. It was shown that the FR3 natural ester liquid has a higher dielectric strength when exposed to positive impulse than when under negative impulse stress. The opposite breakdown behavior was observed for the synthetic ester MIDEL 7131 and the naphthenic oil Shell Diala S4 ZX which exhibited lower breakdown voltage under positive energization as compared with the negative energization. The breakdown voltage and prebreakdown time obtained in the present tests of the naphthenic oil, Shell Diala S4 ZX, lie between that of the ester liquids irrespective of impulse polarity. It has been established that no statistically significant variations exist in the breakdown parameters (breakdown voltage and time to breakdown) of the studied dielectric liquids as their relative humidity is increased under either impulse polarity. The obtained results will help in coordination of practical applications of low environmental impact dielectric fluids in power and pulsed power systems and components

Effect of remote ischaemic conditioning on clinical outcomes in patients with acute myocardial infarction (CONDI-2/ERIC-PPCI): a single-blind randomised controlled trial.

BACKGROUND: Remote ischaemic conditioning with transient ischaemia and reperfusion applied to the arm has been shown to reduce myocardial infarct size in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). We investigated whether remote ischaemic conditioning could reduce the incidence of cardiac death and hospitalisation for heart failure at 12 months. METHODS: We did an international investigator-initiated, prospective, single-blind, randomised controlled trial (CONDI-2/ERIC-PPCI) at 33 centres across the UK, Denmark, Spain, and Serbia. Patients (age >18 years) with suspected STEMI and who were eligible for PPCI were randomly allocated (1:1, stratified by centre with a permuted block method) to receive standard treatment (including a sham simulated remote ischaemic conditioning intervention at UK sites only) or remote ischaemic conditioning treatment (intermittent ischaemia and reperfusion applied to the arm through four cycles of 5-min inflation and 5-min deflation of an automated cuff device) before PPCI. Investigators responsible for data collection and outcome assessment were masked to treatment allocation. The primary combined endpoint was cardiac death or hospitalisation for heart failure at 12 months in the intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT02342522) and is completed. FINDINGS: Between Nov 6, 2013, and March 31, 2018, 5401 patients were randomly allocated to either the control group (n=2701) or the remote ischaemic conditioning group (n=2700). After exclusion of patients upon hospital arrival or loss to follow-up, 2569 patients in the control group and 2546 in the intervention group were included in the intention-to-treat analysis. At 12 months post-PPCI, the Kaplan-Meier-estimated frequencies of cardiac death or hospitalisation for heart failure (the primary endpoint) were 220 (8·6%) patients in the control group and 239 (9·4%) in the remote ischaemic conditioning group (hazard ratio 1·10 [95% CI 0·91-1·32], p=0·32 for intervention versus control). No important unexpected adverse events or side effects of remote ischaemic conditioning were observed. INTERPRETATION: Remote ischaemic conditioning does not improve clinical outcomes (cardiac death or hospitalisation for heart failure) at 12 months in patients with STEMI undergoing PPCI. FUNDING: British Heart Foundation, University College London Hospitals/University College London Biomedical Research Centre, Danish Innovation Foundation, Novo Nordisk Foundation, TrygFonden

The court and household of Edward III, 1360-1377

This thesis is written in two parts. The first part contains an examination of the household functionings as an institution. Although the household was an establishment of declining national importance in the years 1360-1377, due to the fact that Edward III was increasingly separated from it and thus it lost much of its political significance, nevertheless his subjects were on the whole satisfied with the way in which the king ran his household. What complaints there were about its activities were not generalised condemnations but specific complaints aimed at either the jurisdictional competence of the court of the [indecipherable] or the way in which the kings purveyors abused their positions. The numbers of household staff declined steadily during this period, from over 550 in 1359-60 to less than 350 in 1377, the most radical drop being in the early 1360s and probably being due to the fact that the household was no longer involved in the war. Despite the merger of the King’s and Queen’s households in 1360, wardrobe turnover was much reduced by this drop in numbers and by the household's non-involvement in the war; moreover real attempts at economy were made in the household throughout this period. The chamber too had its official income reduced but in actuality its unofficial income probably made it a vary wealthy department in the 1360s although after 1369 most of its wealth was ploughed into the exchequer, by now very much a controlling organ of the national finances, to help to finance the renewed French war. The second part of the thesis examines the part which the royal domestic establishments played in the political upheavals of 1376-77. The Good parliament was not an attack on a system of government, still less an attack on the household. It was a highly personalised attack on a group of courtiers and their associates who had come increasingly to dominate both the kings policies and his patronage in the 1360s and 1370s. Yet with notable exceptions these courtiers were much more than mere idle royal favourites; the commons in the Good Parliament were quick to forget the services which men such as William Latinor, John Yovill and Richard Lyons had done to the state, and while it is true that these men had personally benefitted considerably from their association with the court, nevertheless the charges brought against them in the Good Parliament were in many cases most unfair. Finally, the part played by the lords in the events of 1376-77 in investigated and it is argued that although there was some opposition from the prelates to the government (now virtually ran by John of Gaunt although this was far from being the case before 1376), there really is very little evidence to suggest that the lay magnates either led the opposition in the Good Parliament or seriously opposed government policies in the last year of the reign