8 research outputs found
Probing particle-phonon-coupled states in the neutron-rich nucleus Cu-65 by lifetime measurements with fast-timing techniques
The Cu-65 nucleuswas populated by the Ni-64(Li-7,alpha 2n)Cu-65 reaction
and the lifetime of the 9/2(+) state at 2.5 MeV was measured by
electronic fast-timing technique, providing the value tau = 37(3) ps.
The reduced transition probability B(E3) = 8.82(165) W.u. is deduced and
compared to theoretical predictions in the framework of a
particle-vibration (weak) coupling model. The results indicate that the
9/2(+) state is a member of the 3(-)circle times pi p3/2 multiplet,
built by coupling the octupole 3(-) phonon of Ni-64 to an unpaired
proton in the p(3/2) level, confirming the robustness of core
excitations in the medium mass nucleus Ni-64
The mutable nature of particle-core excitations with spin in the one-valence-proton nucleus ¹³³Sb
The γ-ray decay of excited states of the one-valence-proton nucleus ¹³³Sb has been studied using cold-neutron induced fission of ²³⁵U and ²⁴¹Pu targets, during the EXILL campaign at the ILL reactor in Grenoble. By using a highly efficient HPGe array, coincidences between γ-rays prompt with the fission event and those delayed up to several tens of microseconds were investigated, allowing to observe, for the first time, high-spin excited states above the 16.6 μs isomer. Lifetimes analysis, performed by fast-timing techniques with LaBr₃(Ce) scintillators, revealed a difference of almost two orders of magnitude in B(M1) strength for transitions between positive-parity medium-spin yrast states. The data are interpreted by a newly developed microscopic model which takes into account couplings between core excitations (both collective and non-collective) of the doubly magic nucleus ¹³²Sn and the valence proton, using the Skyrme effective interaction in a consistent way. The results point to a fast change in the nature of particle-core excitations with increasing spin
Electrocardiographic criteria of true left bundle branch block: a simple sign to predict a better clinical and instrumental response to CRT.
Background: Cardiac resynchronization therapy (CRT) has proved to be very effective in improving
morbidity and mortality in patients affected with severe congestive heart failure. Its efficacy has been
shown to be greater in patients with left bundle branch block (LBBB). The aim of our study was to verify
if newly proposed criteria for true LBBB identify patients with a better clinical and instrumental response
to CRT.
Methods: Between May 2007 and April 2011, 111 patients with left ventricular ejection fraction (LVEF)
≤ 35% and LBBB morphology received a CRT device and were divided into two groups according to
QRS morphology. Group 1 (61 patients) consisted of patients with “true” LBBB morphology; group 2 (50
patients) consisted of patients with “false” LBBB. The primary endpoint was the utility of criteria for true
LBBB to predict a composite endpoint of all-cause mortality and hospital admission with heart failure.
The secondary endpoint was the utility of the same criteria to predict an absolute increase in LVEF ≥
10%.
Results: “False” LBBB morphology and a dose of bisoprolol <5 mg at last follow-up were the only
parameters related to clinical outcome in multivariate analysis (respectively: hazard ratio [HR] 3.98,
confidence interval [CI] 95% 1.51–10.48; HR 0.15, CI 95% 0.05–0.43). “True” LBBB morphology was the
only variable significantly related to a greater increase in LVEF (HR 4.57, CI 95% 1.36–8.28).
Conclusion: True LBBB morphology is related to a higher event-free survival rate in CRT patients and
better echocardiographic response
Electrocardiographic criteria of true left bundle branch block: a simple sign to predict a better clinical and instrumental response to CRT.
Background: Cardiac resynchronization therapy (CRT) has proved to be very effective in improving
morbidity and mortality in patients affected with severe congestive heart failure. Its efficacy has been
shown to be greater in patients with left bundle branch block (LBBB). The aim of our study was to verify
if newly proposed criteria for true LBBB identify patients with a better clinical and instrumental response
to CRT.
Methods: Between May 2007 and April 2011, 111 patients with left ventricular ejection fraction (LVEF)
≤ 35% and LBBB morphology received a CRT device and were divided into two groups according to
QRS morphology. Group 1 (61 patients) consisted of patients with “true” LBBB morphology; group 2 (50
patients) consisted of patients with “false” LBBB. The primary endpoint was the utility of criteria for true
LBBB to predict a composite endpoint of all-cause mortality and hospital admission with heart failure.
The secondary endpoint was the utility of the same criteria to predict an absolute increase in LVEF ≥
10%.
Results: “False” LBBB morphology and a dose of bisoprolol <5 mg at last follow-up were the only
parameters related to clinical outcome in multivariate analysis (respectively: hazard ratio [HR] 3.98,
confidence interval [CI] 95% 1.51–10.48; HR 0.15, CI 95% 0.05–0.43). “True” LBBB morphology was the
only variable significantly related to a greater increase in LVEF (HR 4.57, CI 95% 1.36–8.28).
Conclusion: True LBBB morphology is related to a higher event-free survival rate in CRT patients and
better echocardiographic response
The mutable nature of particle-core excitations with spin in the one-valence-proton nucleus Sb
International audienceThe gamma-ray decay of excited states of the one-valence-proton nucleus 133Sb has been studied using cold-neutron induced fission of 235U and 241Pu targets, during the EXILL campaign at the ILL reactor in Grenoble. By using a highly efficient HPGe array, coincidences between gamma-rays prompt with the fission event and those delayed up to several tens of microseconds were investigated, allowing to observe, for the first time, high-spin excited states above the 16.6 micros isomer. Lifetimes analysis, performed by fast-timing techniques with LaBr3(Ce) scintillators, reveals a difference of almost two orders of magnitude in B(M1) strength for transitions between positive-parity medium-spin yrast states. The data are interpreted by a newly developed microscopic model which takes into account couplings between core excitations (both collective and non-collective) of the doubly magic nucleus 132Sn and the valence proton, using the Skyrme effective interaction in a consistent way. The results point to a fast change in the nature of particle-core excitations with increasing spin