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Abstract: Phase-field modeling has been performed to study the domain morphologies of ferroelectric PbTiO3/SrTiO3 superlattice grown on SrTiO3 substrates. Taking into account contributions of the interfacial and depolarization field effects, the polarization, phase transition temperature and critical thickness are calculated as functions of sample dimensions and temperature. The results show that interfacial and depolarization field effects are the main reasons behind the dependence of the domain structures and critical properties (i.e., the phase transition temperature and critical thickness) on the thicknesses of the constituent layers of the PbTiO3/SrTiO3 superlattices. [Copyright &y& Elsevier]

A series of In:Fe:LiNbO3 crystals with various concentration of In2O3 doping were grown in an air atmosphere using the Czochralski method. Spectroscopic properties (fundamental absorption edge, OH vibrational band) were used for an exploration of the defect structure. Light-induced scattering and direct observation of the transmitted laser beam distortion were used to characterize the optical damage. It was found that the threshold intensity of In (3 mol%):Fe:LiNbO3 was 2 orders of magnitude higher than that of Fe:LiNbO3 and was able to withstand higher power level. The increase in damage resistance could be attributed to the Fe3+ losing their electron acceptor properties and therefore an increase in photoconductivity. [Copyright &y& Elsevier]

Purpose: To assess the post-acute activity and clinical utility of reproxalap, a novel reactive aldehyde species (RASP) inhibitor, versus vehicle in patients with seasonal allergic conjunctivitis., Design: Parallel-group, double-masked, randomized Phase 3 trial., Methods: Two topical ocular reproxalap concentrations (0.25% and 0.5%) were evaluated versus vehicle in patients with allergic conjunctivitis randomized 1:1:1 and treated with test article 10 minutes prior to conjunctival seasonal allergen challenge. The primary endpoint was area under the post-acute ocular itching score (range = 0-4) curve from 10 to 60 minutes after challenge. The key secondary endpoint was the proportion of subjects with ≥2 points improvement from their peak ocular itching score at baseline., Results: A total of 318 patients were randomized at 11 US sites. Both concentrations of reproxalap (0.25% and 0.5%) achieved the primary endpoint (P < .0001 and P = .003, respectively) and the key secondary endpoint (P = .0005 and P = .02, respectively). Time to complete resolution of ocular itching was statistically faster for both reproxalap concentrations than for vehicle (P < .0001 and P = .001, respectively). No safety or tolerability concerns were noted. The most common adverse event was mild and transient instillation site irritation., Conclusion: Reproxalap was effective at reducing ocular itching in patients with allergic conjunctivitis. Reproxalap activity was clinically relevant, as assessed by responder-based and distributional analyses. ALLEVIATE represents one of the first allergic conjunctivitis Phase 3 trials of a novel mechanism of action in decades, and is unique among conjunctival allergen challenge trials in assessing clinical relevance with standard and validated techniques., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background: His bundle pacing (HBP) remains technically challenging and is currently guided by electrograms and 2-dimensional fluoroscopy. Our objective was to describe a new technique for HBP directly guided by electroanatomic mapping (EAM)., Methods: Twenty-eight patients were included. The atrioventricular septum was mapped via EAM, and His bundle (HB) electrograms, selective, and nonselective HB capture sites were tagged. Pacing leads were connected to EAM, navigated to tagged HB target sites and deployed. Intracardiac electrograms and pacing parameters were recorded. Lead location was tagged on the cloud of HB sites, which was divided into 3 arbitrary segments. In 5 patients, atrioventricular nodal ablation was performed with direct visualization of the HBP lead by EAM., Results: Reproducible navigation of the pacing lead to predetermined HBP locations guided by EAM was achieved in all patients. The lead was successfully deployed in 25 patients. HB cloud area was 360 (212) mm 2 . There was no correlation between HBP threshold and lead location on the His cloud. The intracardiac electrograms atrial/ventricular ratio at the lead deployment site correlated with its EAM position on the His cloud ( P=0.045). Procedure, fluoroscopy, and mapping times were 116.0 (38.8), 8.6 (6.3), and 9.0 (11.4) minutes, respectively. HBP threshold at implant was 1.5 (2.3) V at 1.5 (1.0) ms. Distance between HB lead and ablation sites was 10.0 (1.3) mm in patients undergoing atrioventricular nodal ablation., Conclusions: Direct guidance of HBP by EAM allows for direct visualization of the pacing lead on the HB cloud and reproducible navigation to predetermined HB capture sites. Intracardiac electrograms atrial/ventricular ratio at the lead deployment site correlates with His cloud location. EAM can be applied during standard HBP procedures or combined with atrioventricular nodal ablation.

The Academic Research Consortium (ARC)-2 initiative revisited the clinical and angiographic end point definitions in coronary device trials, proposed in 2007, to make them more suitable for use in clinical trials that include increasingly complex lesion and patient populations and incorporate novel devices such as bioresorbable vascular scaffolds. In addition, recommendations for the incorporation of patient-related outcomes in clinical trials are proposed. Academic Research Consortium-2 is a collaborative effort between academic research organizations in the United States and Europe, device manufacturers, and European, US, and Asian regulatory bodies. Several in-person meetings were held to discuss the changes that have occurred in the device landscape and in clinical trials and regulatory pathways in the last decade. The consensus-based end point definitions in this document are endorsed by the stakeholders of this document and strongly advocated for clinical trial purposes. This Academic Research Consortium-2 document provides further standardization of end point definitions for coronary device trials, incorporating advances in technology and knowledge. Their use will aid interpretation of trial outcomes and comparison among studies, thus facilitating the evaluation of the safety and effectiveness of these devices., (© 2018 American Heart Association, Inc., and European Society of Cardiology.)