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Conical intersections (CIs) are pivotal in many photochemical processes. Traditional quantum chemistry methods, such as the state-average multiconfigurational methods, face computational hurdles in solving the electronic Schrödinger equation within the active space on classical computers. While quantum computing offers a potential solution, its feasibility in studying CIs, particularly on real quantum hardware, remains largely unexplored. Here, we present the first successful realization of a hybrid quantum-classical state-average complete active space self-consistent field method based on the variational quantum eigensolver (VQE-SA-CASSCF) on a superconducting quantum processor. This approach is applied to investigate CIs in two prototypical systems─ethylene (C 2 H 4 ) and triatomic hydrogen (H 3 ). We illustrate that VQE-SA-CASSCF, coupled with ongoing hardware and algorithmic enhancements, can lead to a correct description of CIs on existing quantum devices. These results lay the groundwork for exploring the potential of quantum computing to study CIs in more complex systems in the future.

Post-translational modifications of histone proteins regulate a long cascade of downstream cellular activities, including transcription and replication. Cellular lineage differentiation involves large-scale intracellular signaling and extracellular context. In particular, histone modifications play instructive and programmatic roles in central nervous system development. Deciphering functions of histone could offer feasible molecular strategies for neural diseases caused by histone modifications. Here, we review recent advances of in vitro and in vivo studies on histone modifications in neural differentiation., Competing Interests: The authors declare no conflict of interest., (© 2021 Published by Elsevier Ltd.)

Control of excited-state dynamics is key in tuning room-temperature phosphorescence (RTP) and thermally activated delayed fluorescence (TADF) emissions but is challenging for organic luminescent materials (OLMs). We show the regulation of TADF and RTP emissions of a boron difluoride β-acetylnaphthalene chelate (βCBF 2 ) by controlling the excited-state dynamics via its J- and H-aggregation states. Two crystalline polymorphs emitting green and red light have been controllably obtained. Although both monoclinic, the green and red crystals are dominated by J- and H-aggregation, respectively, owing to different molecular packing arrangements. J-aggregation significantly reduces the energy gap between the lowest singlet and triplet excited states for ultra-fast reverse intersystem crossing (RISC) and enhances the radiative singlet decay, together leading to TADF. The H-aggregation accelerates the ISC and suppresses the radiative singlet decay, helping to stabilize the triplet exciton for RTP., (© 2021 Wiley-VCH GmbH.)

Objective: This study aimed to investigate the effects of combined activin A and Wnt3a treatment on definitive endoderm (DE) differentiation from human parthenogenetic embryonic stem cells (hPESCs)., Methods: hPESCs on human foreskin fibroblast feeder layers were induced to differentiate into DE using a combination of 50 ng/ml activin A and 25 ng/ml Wnt3a. Expression of the DE markers CXCR4, E-cadherin (ECD), Sox17, and Goosecoid (Gsc) were examined using flow cytometry and real-time quantitative PCR., Results: The combination of activin A and Wnt3a significantly enhanced the percentages of CXCR4 + , ECD + , Sox17 + , and Gsc + cells, culminating on day 2 of induction. This combined use promoted DE differentiation from hPESCs in vitro ., Conclusions: Through the combination treatment using activin A and Wnt3a, DE differentiation from hPESCs culminated at 48 h, which can be regarded as the optimal time-point to induce differentiation of endodermal cells such as pancreatic, liver, and intestinal cells., (© 2020 by the Association of Clinical Scientists, Inc.)