Pinocembrin is one of the most abundant flavonoids in propolis, and it may also be widely found in a variety of plants. In addition to natural extraction, pinocembrin can be obtained by biosynthesis. Biosynthesis efficiency can be improved by a metabolic engineering strategy and a two-phase pH fermentation strategy. Pinocembrin poses an interest for its remarkable pharmacological activities, such as neuroprotection, anti-oxidation, and anti-inflammation. Studies have shown that pinocembrin works excellently in treating ischemic stroke. Pinocembrin can reduce nerve damage in the ischemic area and reduce mitochondrial dysfunction and the degree of oxidative stress. Given its significant efficacy in cerebral ischemia, pinocembrin has been approved by China Food and Drug Administration (CFDA) as a new treatment drug for ischemic stroke and is currently in progress in phase II clinical trials. Research has shown that pinocembrin can be absorbed rapidly in the body and easily cross the blood–brain barrier. In addition, the absorption/elimination process of pinocembrin occurs rapidly and shows no serious accumulation in the body. Pinocembrin has also been found to play a role in Parkinson’s disease, Alzheimer’s disease, and specific solid tumors, but its mechanisms of action require in-depth studies. In this review, we summarized the latest 10 years of studies on the biosynthesis, pharmacological activities, and pharmacokinetics of pinocembrin, focusing on its effects on certain diseases, aiming to explore its targets, explaining possible mechanisms of action, and finding potential therapeutic applications.

We have implemented the calculations of NMR parameters within the generalized energy-based fragmentation (GEBF) method for condensed-phase systems with periodic boundary conditions (PBC). In this PBC-GEBF approach, NMR parameters of molecules in a unit cell are assembled as a linear combination of the corresponding quantities from a series of small embedded subsystems. To treat condensed-phase systems containing large molecules, we propose a novel “fragment-based” strategy for building subsystems, while our previously reported “molecule-based” strategy for construction of subsystems is appropriate for periodic systems with small molecules. The “fragment-based” strategy in PBC-GEBF is demonstrated to be much more efficient than its “molecule-based” counterpart to treat crystals of large molecules. With the “molecule-based” PBC-GEBF method, we obtained consistently good NMR parameters of liquid water with B3LYP on top of neural-network-potential-based ab initio molecular dynamics (AIMD) snapshots. With the “fragment-based” PBC-GEBF approach, we predicted the 1H chemical shifts of a large macrocycle in solution based on a series of classical MD snapshots. The calculated results are in good accord with the experimental chemical shifts. Therefore, the PBC-GEBF method is expected to be a reliable and efficient tool for predicting NMR parameters of large complex systems in solutions.

some outstanding features, such as a high carrier mobility, [8][9][10] a high thermal conductivity, [11] flexibility, [12] and visible transparency. [13,14] Moreover, it can be used as a removable layer for the epitaxial growth of III-Ns, thus providing the foundation for a new field of transferable and flexible LEDs. [15,16] Recently, graphene has been used as a buffer layer for the van der Waals epitaxy growth of a GaN epilayer to overcome the substantial thermal expansion coefficient and in-plane lattice constant mismatch between the GaN epilayer and sapphire substrate (c-Al 2 O 3 ), which causes a significant strain in the GaN epilayer. However, because the graphene surface lacks dangling bonds, the nucleation of nitrides on graphene is restricted, and clusters are easily formed. [17,18] In this study, theoretical calculations using first-principles calculations based on density functional theory (DFT) were carefully conducted to further examine the formation mechanism of AlN and GaN on graphene. We found that AlN selectively grows on graphene, and we identified its optimal nucleation site. We obtained the adsorption probability of Al atoms at various positions on the graphene CC ring and found that the hollow of the complete graphene CC ring and the center of the broken graphene CC ring are the best adsorption positions under different states of the graphene. Based on this, we innovatively inserted an AlN composite nucleation layer between graphene and GaN, which was grown by metal organic chemical vapor deposition (MOCVD) using time-distributed and constant-pressure (TDCP) growth. The growth process for AlN is divided into three stages. Under the same pressure, different flow rates, and growth temperatures are used for each stage. By controlling the growth time at different flow rates, an AlN composite nucleation layer on graphene can be formed. By introducing the selective nucleation of an AlN composite layer and graphene, the biaxial stress of the GaN film was effectively released, leading to transferable and low density dislocations in the GaN film and the In 0.1 Ga 0.9 N/GaN multiple quantum well structures. Note that LEDs with an ultrahigh light output power (LOP) of 260.5 mW at a small current of 560 mA were achieved. Our study demonstrates a practical application of an AlN composite nucleation layer grown on graphene that may result in A transferable GaN epilayer is grown on an improved aluminum nitride (AlN)/graphene composite substrate. In this study, theoretical calculations using first-principles calculations based on density functional theory are carefully conducted to further examine the formation mechanism of AlN on graphene. AlN selectively grows on graphene via its optimal nucleation site, which leads to the selective nucleation of AlN on graphene via quasi-van der Waals epitaxy. Thus, an AlN composite nucleation layer is innovatively inserted between graphene and GaN, using the time-distributed and constant-pressure growth method by metal organic chemical vapor deposition. Moreover, a hi...

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