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We theoretically investigate microscopic origins of vibronic coupling (VC) contributing to singlet fission (SF) dynamics in pentacene and its halogenated derivatives. The features of VCs related to diabatic exciton states and interstate electronic couplings (Holstein and Peierls couplings, respectively) are interpreted by the VC density (VCD) analysis, which allows one to clarify the relationship between the chemical structure and VC as spatial contribution. It is found for the pentacene dimer face-to-edge configuration in a herringbone crystal that characteristic intermolecular vibrations with low frequencies exhibit strong Holstein couplings for the intermediate charge-transfer (CT) exciton states as well as Peierls couplings. From VCD analysis, the comprising density of the intermolecular CT and that of the intermolecular vibration are found to be constructively mixed in the intermolecular space, leading to the enhancement of VC. Moreover, in order to assess the chemical modification manner for controlling VC, we design several halogenated pentacene derivatives with slip-stack configurations. Our strategy to enhance VCD by halogenation is found to be rational, whereas the peaks of VC spectra for the CT states in the slip-stack packings are observed in high frequency regions. We compare their SF dynamics based on the quantum master equation explicitly including the exciton state-dependent VCs. From the analysis on relative relaxation factors between the adiabatic exciton states, their difference in the SF rate is highlighted by exciton configurations in addition to VCs. The present study is expected to be a first step toward efficient SF based on the design of VC in terms of both the chemical structure and intermolecular packing. [ABSTRACT FROM AUTHOR]

Theoretical molecular design of efficient nonlinear optical (NLO) systems using singlet fission (SF) is performed for butterfly-shaped acenes with/without nitrogen and sulfur substitutions using quantum chemical calculations, exciton dynamics simulations, and Marcus theory. It is found that these large systems meet the energy level matching conditions of efficient SF and exhibit superior third-order NLO properties (second hyperpolarizability γ at the molecular scale) to a typical SF molecule, pentacene. In addition, we investigate SF rates and γ in the correlated triplet pair [1(TT)] state generated by SF for various slip-stacked dimer models of these systems. For molecular packing with relatively large 1(TT) yields, a significant increase in γ/monomer in the 1(TT) state is observed, which is in good agreement with the electronic-coupling-based design guidelines obtained from our previous study. In particular, the butterfly-shaped acenes involving heteroatoms are found to exhibit a significant increase in γ/monomer as compared to the other systems. By analyzing the excitation properties in the 1(TT) state and intermolecular orbital interactions, we clarify the origin of such γ enhancement. The obtained results contribute to the construction of design guidelines for efficient SF-induced-NLO materials and demonstrate that butterfly-shaped acenes have the potential to surpass conventional NLO systems. [ABSTRACT FROM AUTHOR]

Aims Post-extubation dysphagia (PED), an often overlooked problem, is a common and serious complication associated with mortality and major morbidity after cardiovascular surgery. Dysphagia is considered an age-related disease, and evaluating its long-term effects is a pressing issue with rapidly progressing ageing worldwide. Therefore, we examined the effect of PED on functional status and long-term cardiovascular events in patients undergoing cardiovascular surgery. Methods and results This single-centre, retrospective cohort study included 712 patients who underwent elective cardiovascular surgery and met the inclusion criteria. Patients were divided into PED and non-PED groups based on their post-operative swallowing status. The swallowing status was assessed using the Food Intake Level Scale. Functional status was evaluated as hospital-associated disability (HAD), defined as a decrease in activities of daily living after hospital discharge compared with preoperative values. The patients were subsequently followed up to detect major adverse cardiac and cerebrovascular events (MACCEs). Post-extubation dysphagia was present in 23% of the 712 patients and was independently associated with HAD (adjusted odds ratio, 2.70). Over a 3.5-year median follow-up period, MACCE occurred in 14.1% of patients. Multivariate Cox proportional hazard analysis revealed HAD to be independently associated with an increased risk of MACCE (adjusted hazard ratio, 1.85), although PED was not significantly associated with MACCE. Conclusion Post-extubation dysphagia was an independent HAD predictor, with the odds of HAD occurrence being increased by 2.7-fold due to PED. Hospital-associated disability accompanied by PED is a powerful predictor of poor prognosis. Perioperative evaluation and management of the swallowing status, and appropriate therapeutic interventions, are warranted. [ABSTRACT FROM AUTHOR]

Introduction: An easy-to-use, multiuse, single-patient, electromechanical autoinjector, the SMARTCLIC®/CLICWISE® injection device, was recently developed to improve the self-administration options available to patients with chronic inflammatory disease treated with biologic agents. An extensive series of studies were conducted to guide the design and development of this device and to ensure its safety and effectiveness. Methods: Participants in two user preference studies and three formative human factor (HF) studies evaluated evolving iterations of the autoinjector device, dose dispenser cartridge, graphical user interface, and informational materials; participants in a summative HF test subsequently assessed the final proposed commercially representative product. In the user preference studies, rheumatologists and patients with chronic inflammatory disease, interviewed online and in-person, provided feedback on the design and functionality of four prototypes. In the HF studies, the safety, effectiveness, and usability of adapted prototypes were assessed under simulated-use conditions by patients with chronic inflammatory disease, caregivers, and healthcare professionals (HCPs). The safety and effectiveness of the final refined device and system were confirmed in a summative HF test by patients and HCPs in simulated-use scenarios. Results: Rheumatologists (n = 204) and patients (n = 39) interviewed in the two user preference studies provided feedback on the device size, feature ergonomics, and usability that guided prototype development in the subsequent formative HF studies. Observations from patients, caregivers, and HCPs (n = 55) participating in the latter studies yielded additional critical design revisions that culminated in development of the final device and system. Of 106 injection simulations conducted in the summative HF test, all resulted in successful medication delivery, and no potential harms were associated with injection-related use events. Conclusion: Findings from this research facilitated development of the SmartClic/ClicWise autoinjector device and demonstrated that it could be used safely and effectively by participants representative of the intended-use population of patients, lay caregivers, and HCPs. [ABSTRACT FROM AUTHOR]