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The effects of spin-orbit (SOC) and electron-phonon coupling on the collective excitation of doped monolayer Sb2 are investigated using density functional and many-body perturbation theories. The spin-orbit coupling is exclusively important for the monolayer Sb2 and it leads to the reconstruction of the electronic band structure. In particular, plasmon modes of monolayer Sb2 are quite sensitive to the SOC and are characterized by very low damping rates owing to small electron-phonon scatterings. Our results show plasmons in antimonene are significantly less damped compared to monolayer graphene when plasmon energies are ω > 0.2 eV due to smaller plasmon-phonon coupling in the former material.

We study the effects of Kohn anomalies on the superconducting properties in electron- and hole-doped cases of monolayer blue phosphorene, considering both adiabatic and non-adiabatic phonon dispersions using first-principle calculations. We show that the topology of the Fermi surface is crucial for the formation of Kohn anomalies of doped blue phosphorene. By using the anisotropic Eliashberg formalism, we further carefully consider the temperature dependence of the non-adiabatic phonon dispersions. In cases of low hole densities, strong electron-phonon coupling leads to a maximum critical temperature of Tc = 97 K for superconductivity. In electron-doped regimes, on the other hand, a maximum superconducting critical temperature of Tc = 38 K is reached at a doping level that includes a Lifshitz transition point. Furthermore, our results indicate that the most prominent component of electron-phonon coupling arises from the coupling between an in-plane (out-of-plane) deformation and in-plane (out-of-plane) electronic states of the electron (hole) type doping.

Primary percutaneous coronary intervention (PPCI) is the gold standard of treatment in patients with acute ST-elevation myocardial infarction (STEMI). The no-reflow phenomenon (NRP) is a detrimental consequence of STEMI. Colchicine is an antiinflammatory drug that may help prevent the NRP and improve patient outcomes. In a randomized, double-blind, placebo-controlled clinical trial, 451 patients with acute STEMI who were candidates for PPCI and eligible for enrollment were randomized into the colchicine group (n = 229) and the control group (n = 222). About 321 patients were eligible to participate; 161 patients were assigned to the colchicine group, whereas 160 patients were assigned to the control group. Colchicine was administered 1 mg before PCI and 0.5 mg daily after the procedure until discharge. NRP, measured by angiographic findings including the thrombolysis in myocardial infarction flow grade and the thrombolysis in myocardial infarction myocardial perfusion grade, was reported as the primary outcome. Secondary end points included ST resolution 90 minutes after the procedure, P-selectin, high-sensitivity C-reactive protein, and troponin levels postprocedurally, predischarge ejection fraction, and major adverse cardiac events (MACE) at 1 month and 1 year after PPCI. NRP rates did not show a significant difference between the 2 groups (P = 0.98). Moreover, the levels of P-selectin, high-sensitivity C-reactive protein, and troponin were not significantly different. MACE and predischarge ejection fraction were also not significantly different between the groups. In patients with STEMI treated by PPCI, colchicine administered before PPCI was not associated with a signif-icant reduction in the NRP and MACE prevention (trial registration: IRCT20120111008698N23).

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A multiscale modeling and simulation approach, including first-principles calculations, ab initio molecular dynamics simulations, and a tight binding approach, is employed to study band flattening of the electronic band structure of oxidized monolayer graphene. The width of flat bands can be tuned by strain, the external electric field, and the density of functional groups and their distribution. A transition to a conducting state is found for monolayer graphene with impurities when it is subjected to an electric field of ∼1.0 V/Å. Several parallel impurity-induced flat bands appear in the low-energy spectrum of monolayer graphene when the number of epoxy groups is changed. The width of the flat band decreases with an increase in tensile strain but is independent of the electric field strength. Here an alternative and easy route for obtaining band flattening in thermodynamically stable functionalized monolayer graphene is introduced. Our work discloses a new avenue for research on band flattening in monolayer graphene.

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We have investigated the piezoelectric response of the hydrogenated graphene oxide (H-G-SiO2) stacks both experimentally and theoretically. The piezoresponse force microscopy method and density-functional theory (DFT) calculations were used to study the piezoresponse effect of this structure from both experimental and computational point of views. A mono-layer graphene, made by chemical vapour deposition method, is deposited on Si/SiO2 substrate and its surface is then functionalized with hydrogen atoms. The vertical piezoresponse, observed by piezoresponse force microscopy, is measured to be about 2146 pC N−1, that is comparable to the reported state of the art piezoelectric materials such as relaxor-based ferroelectric single crystals. In order to carry out the DFT modelling, a H-Graphene-O Janus structure has been adopted, where graphene is modified by oxygen atoms adsorbed on one side while hydrogen atoms are placed on the other side. Through modelling by DFT calculations, it is revealed that, by applying out-of-plane compressive uniaxial strain, the structure preforms different piezoelectric behaviours, up to three orders of magnitude alteration by the applied strain. The demonstrated approach for enhancing the piezo-response of graphene paves the way for realizing graphene-based nanoscale sensors, actuators and transducers.