8 research outputs found

    AN ANALYTICAL METHOD TO CALCULATE THE ERGODIC AND DIFFERENCE MATRICES OF THE DISCOUNTED MARKOV DECISION PROCESSES

    Get PDF
    In the paper, a theorem about the existence of the ergodic and difference matrices of the finite state discounted Markov decision processes had been formulated and proved. On the basis of this theorem an analytical method to calculate these matrices is presented. The theorem allows the distribution of the overall value into two parts: the so-called "constant" part, which represents a part of the value related to the ergodic matrix and the "variable" part which represents a sum of the difference matrices. On the basis of the mentioned analytical method a new performance index to the discounted optimal control Markov problem is proposed and some interpretation of the received results is given. The proposed new performance index is formulated as a quotient of the distinguished parts of the overall value. The method is illustrated by two simple examples.

    Pest categorisation of the Ralstonia solanacearum species complex

    Get PDF
    Following a request from the European Commission, the EFSA Panel on Plant Health performed a pest categorisation of the Ralstonia solanacearum species complex (RSSC), a distinguishable cosmopolitan group of bacterial plant pathogens (including R. solanacearum, Ralstonia pseudosolanacearum and two subspecies of Ralstonia syzygii) of the family Burkholderiaceae. The RSSC causes bacterial wilt in solanaceous crops, such as potato, tomato and pepper, but can also cause wilts in other important food crops such as fruit banana, plantain banana and cassava. The pest survives in the soil, and a number of weed species can also be infected by the pest, often asymptomatically. The RSSC is regulated in Council Directive 2000/29/EC (Annex IAII) (indicated by its former name R. solanacearum, as delimited by Yabuuchi et al.) as a harmful organism whose introduction into the EU is banned. In addition, Council Directive 1998/57/EC (amended by Commission Directive 2006/63/CE) concerns the measures to be taken within EU Member States (MS) against the RSSC to (a) detect it and determine its distribution, (b) prevent its occurrence and spread, and (c) control it with the aim of eradication. The pest is present in several EU MS, but in all cases with a restricted distribution and under official control. New phylotypes of the RSSC could enter the EU primarily via host plants for planting (including seed tubers). The pest could establish in the EU, as climatic conditions are favourable, hosts are common and the pathogen has high adaptability. Spread is mainly via plants for planting. Substantial crop losses in the EU would occur in the presence of RSSC epidemics. The RSSC is regarded as one of the world’s most important phytopathogenic bacteria due to its broad geographical distribution, large host range, aggressiveness, genetic diversity and long persistence in soil and water. The list of hosts and commodities for which the pest is regulated is incomplete due to the high diversity of hosts and the lack of knowledge of the complete host range. Moreover, the comparative epidemiology of the different pathogen species has not yet been studied. The criteria assessed by the Panel for consideration of the RSSC as potential quarantine pest are met, while, for regulated non-quarantine pests, the criterion on the widespread presence in the EU is not met

    Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

    Get PDF
    Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≄ II, EF ≀35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure < 100 mmHg (n = 1127), estimated glomerular filtration rate < 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

    Cardiac myosin activation with omecamtiv mecarbil in systolic heart failure

    No full text
    BACKGROUND The selective cardiac myosin activator omecamtiv mecarbil has been shown to improve cardiac function in patients with heart failure with a reduced ejection fraction. Its effect on cardiovascular outcomes is unknown. METHODS We randomly assigned 8256 patients (inpatients and outpatients) with symptomatic chronic heart failure and an ejection fraction of 35% or less to receive omecamtiv mecarbil (using pharmacokinetic-guided doses of 25 mg, 37.5 mg, or 50 mg twice daily) or placebo, in addition to standard heart-failure therapy. The primary outcome was a composite of a first heart-failure event (hospitalization or urgent visit for heart failure) or death from cardiovascular causes. RESULTS During a median of 21.8 months, a primary-outcome event occurred in 1523 of 4120 patients (37.0%) in the omecamtiv mecarbil group and in 1607 of 4112 patients (39.1%) in the placebo group (hazard ratio, 0.92; 95% confidence interval [CI], 0.86 to 0.99; P = 0.03). A total of 808 patients (19.6%) and 798 patients (19.4%), respectively, died from cardiovascular causes (hazard ratio, 1.01; 95% CI, 0.92 to 1.11). There was no significant difference between groups in the change from baseline on the Kansas City Cardiomyopathy Questionnaire total symptom score. At week 24, the change from baseline for the median N-terminal pro-B-type natriuretic peptide level was 10% lower in the omecamtiv mecarbil group than in the placebo group; the median cardiac troponin I level was 4 ng per liter higher. The frequency of cardiac ischemic and ventricular arrhythmia events was similar in the two groups. CONCLUSIONS Among patients with heart failure and a reduced ejection, those who received omecamtiv mecarbil had a lower incidence of a composite of a heart-failure event or death from cardiovascular causes than those who received placebo. (Funded by Amgen and others; GALACTIC-HF ClinicalTrials.gov number, NCT02929329; EudraCT number, 2016 -002299-28.)

    Cardiovascular Efficacy and Safety of Bococizumab in High-Risk Patients

    No full text
    BACKGROUN
    corecore