Modified Conjugate Gradient Method for Unconstrained Optimization

Conjugate gradient method holds an important role in solving unconstrained Optimizations, especially for large scale problems. Numerous studies and modific ations have been done to improve this method. In this paper, we propose a new conjugate gradient meth od which is computed by modifying Dai and Yuan formula. This new � k formula for the denominator is introduced and the numerator of Dai and Yuan for mula is retrained, but still possesses global converge nce properties. Numerical results based on number of iterations and number of function evaluations by usin g exact line search have shown that the new formul a is an efficient when we comparative it with the oth er conjugate gradient methods

Assessing the cardiology community position on transradial intervention and the use of bivalirudin in patients with acute coronary syndrome undergoing invasive management: results of an EAPCI survey.

AIMS: Our aim was to report on a survey initiated by the European Association of Percutaneous Cardiovascular Interventions (EAPCI) collecting the opinion of the cardiology community on the invasive management of acute coronary syndrome (ACS), before and after the MATRIX trial presentation at the American College of Cardiology (ACC) 2015 Scientific Sessions. METHODS AND RESULTS: A web-based survey was distributed to all individuals registered on the EuroIntervention mailing list (n=15,200). A total of 572 and 763 physicians responded to the pre- and post-ACC survey, respectively. The radial approach emerged as the preferable access site for ACS patients undergoing invasive management with roughly every other responder interpreting the evidence for mortality benefit as definitive and calling for a guidelines upgrade to class I. The most frequently preferred anticoagulant in ACS patients remains unfractionated heparin (UFH), due to higher costs and greater perceived thrombotic risks associated with bivalirudin. However, more than a quarter of participants declared the use of bivalirudin would increase after MATRIX. CONCLUSIONS: The MATRIX trial reinforced the evidence for a causal association between bleeding and mortality and triggered consensus on the superiority of the radial versus femoral approach. The belief that bivalirudin mitigates bleeding risk is common, but UFH still remains the preferred anticoagulant based on lower costs and thrombotic risks