Search results for "CROSSOVER"
showing 10 items of 658 documents
Permanent left atrial pacing therapy may improve symptoms in heart failure patients with preserved ejection fraction and atrial dyssynchrony: a pilot…
2012
Aims Our group has recently shown that in some patients, heart failure with preserved ejection fraction (HFPEF) may be explained by ‘atrial dyssynchrony syndrome’ (ADS) due to interatrial conduction delay (IACD), a short left atrioventricular interval (LAVI), and increased left atrial (LA) stiffness. Our primary objective was to evaluate LA pacing therapy as a new treatment to restore left ventricular active filling in patients with no other known causes for HF than ADS. Methods and results Six patients with severe HFPEF with IACD (P wave duration >120 ms in lead II), short LAVI during electrophysiological studies ( 15), and no standard indication for a pacemaker were implanted with a lead …
Cooperative Spin‐Crossover Behaviour in Polymeric 1D Fe II Coordination Compounds: [{Fe(tba) 3 }X 2 ]· n H 2 O
2007
A new family of 1D cooperative spin-crossover polymers with general formula [{Fe(tba)3}X2]·nH2O [tba = N-(4H-1,2,4-triazol-4-yl)benzamide; X = CF3SO3–, n = 2 (1), n = 0 (4); BF4–,n = 3 (2), n = 0 (5); 4-CH3C6H4SO3–, n = 3 (3), n = 0 (6)] has been synthesised and characterised using a series of spectroscopic methods, X-ray powder diffraction, magnetic susceptibility measurements and differential scanning calorimetry. The copper analogue of 1, [{Cu(tba)3}(CF3SO3)2]·3H2O (7), has also been synthesised and its crystal structure solved at 293 K. Compound 7 crystallises in the P space group. The bidentate N-(4H-1,2,4-triazol-4-yl)benzamide ligand bridges the copper ions through the 1,2-nitrogen p…
Quasielastic neutron scattering study of dynamics at the crossover from dilute to semidilute behavior in polymer solutions
1982
The impact of aircraft noise on vascular and cardiac function in relation to noise event number: a randomized trial
2020
Abstract Aims Nighttime aircraft noise exposure has been associated with increased risk of hypertension and myocardial infarction, mechanistically linked to sleep disturbance, stress, and endothelial dysfunction. It is unclear, whether the most widely used metric to determine noise exposure, equivalent continuous sound level (Leq), is an adequate indicator of the cardiovascular impact induced by different noise patterns. Methods and results In a randomized crossover study, we exposed 70 individuals with established cardiovascular disease or increased cardiovascular risk to two aircraft noise scenarios and one control scenario. Polygraphic recordings, echocardiography, and flow-mediated dila…
Communication between iron(II) building blocks in cooperative spin transition phenomena
2003
[EN] In the present article we discuss the cooperative nature of the spin crossover phenomenon in iron(II) complexes, providing a perspective of the state of the art in this area. The first aspect we discuss is the role of the intermolecular interactions, more precisely the ¿-interactions, in mononuclear complexes. We show that by playing with the nature of the ligands, aliphatic, aromatic, or extended aromatic, it is possible to create stronger cohesive forces and receive a more cooperative response from the compound. In the next step the singular family of bipyrimidine-bridged iron(II) dinuclear compounds is presented as the simplest example of polynuclear spin crossover complexes exhibit…
Enhanced bistability by guest inclusion in Fe(ii) spin crossover porous coordination polymers
2012
Inclusion of thiourea guest molecules in the tridimensional spin crossover porous coordination polymers {[Fe(pyrazine)[M(CN)(4)]} (M = Pd, Pt) leads to novel clathrates exhibiting unprecedented large thermal hysteresis loops of ca. 60 K wide centered near room temperature.
Pressure effect on temperature induced high-spin–low-spin phase transitions
2002
The effect of hydrostatic pressure on the transition temperature and the hysteresis widths of first-order spin crossover phase transitions is considered in the frame of the mean field theory and on the basis of the scope of recent pressure experiments. Relevant parameters for a qualitative description of the behaviour of spin transition compounds under pressure are derived and analysed.
Spin‐Crossover Complexes
2013
EurJIC is proud to present a bumper issue on Spin-Crossover Complexes. Our Guest Editors, Keith Murray, Hiroki Oshio and Jose Antonio Real, have worked hard to put together a fantastic issue. With a valuable personal account of the field by Philipp Gutlich and inspiring papers by leading experts, you will not be disappointed.
Anodal transcranial direct current stimulation and intermittent theta-burst stimulation improve deglutition and swallowing reproducibility in elderly…
2019
Background: Dysphagia in the elderly, known as presbydysphagia, has become a relevant public health problem in several countries. Swallowing disorders may be a consequence of different neurological disorders (secondary presbydysphagia) or the expression of the aging process itself (primary presbydysphagia). We aimed to test the therapeutic potential of two different non-invasive brain stimulation (NIBS) techniques in subjects with primary or secondary presbydysphagia. Methods: A blinded randomized controlled trial with crossover design was carried out in 42 patients, randomly assigned to anodal transcranial direct current stimulation (tDCS) or intermittent theta-burst stimulation (TBS) grou…
Continuum limit in random sequential adsorption.
1991
We develop analytical estimates of the late-stage (long-time) asymptotic behavior of the coverage in the D-dimensional lattice models of irreversible deposition of hypercube-shaped particles. Our results elucidate the crossover from the exponential time dependence for the lattice case to the power-law behavior with a multiplicative logarithmic factor, in the continuum deposition. Numerical Monte Carlo results are reported for the two-dimensional (2D) deposition, both lattice and continuum. Combined with the exact 1D results, they are used to test the general theoretical expectations for the late-stage deposition kinetics. New accurate estimates of the jamming coverages in 2D rule out some e…