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In this study, we report a simple and reliable high-performance liquid chromatography coupled with diode array detection method for simultaneous and quantitative analysis and comparison of major phenolic compounds dominant phytochemicals in Chrysanthemum morifolium, Florists chrysanthemum and snow chrysanthemum (Coreopsis tinctoria or C. tinctoria). The chromatographic separation was achieved using a reversed phase C18 column with a mobile phase of water [containing 0.1% trifluoroacetic acid (TFA)] and acetonitrile. The major phenolic compounds were completely separated within 16 min at a flow rate of 1.0 mL/min. Flavonoid and phenolic acid profiles of the ethanol extracts of the three flowers were analyzed. The results revealed that C. tinctoria possessed the highest amount of flavonoids (flavanomarein, flavanokanin, marein and okanin) and relative lower content of phenolic acid (chlorogenic acid and 3,5-dicafeoylquinic acid). The total content of the four flavonoids in C. tinctoria reached 53.99 ± 1.32 mg/g. In particular, the marein content in C. tinctoria was as high as 36.50 mg/g. Flavanomarein was only detected in C. tinctoria, whereas chlorogenic acid and 3,5-dicafeoylquinic acid were abundant in Chrysanthemum morifolium and Florists chrysanthemum. The content of marein in Chrysanthemum morifolium was slightly higher than that in Florists chrysanthemum, whereas no okanin was detected in Florists chrysanthemum under these high-performance liquid chromatography conditions. The results indicated phenolic components differ significantly depending on the cultivar, especially between C. tinctoria and common commercially available chrysanthemums. The method adopted in this study is helpful for quality control of different chrysanthemum species as well as their products, which is essential for usage and functionality clarification.The functional and computational properties of brain areas are determined, in large part, by their connectivity profiles. Advances in neuroimaging and network neuroscience allow us to characterize the human brain noninvasively, but a comprehensive understanding of the human brain demands an account of the anatomy of brain connections. Long-range anatomical connections are instantiated by white matter, which itself is organized into tracts. These tracts are often disrupted by central nervous system disorders, and they can be targeted by neuromodulatory interventions, such as deep brain stimulation. Here, we characterized the connections, morphology, traversal, and functions of the major white matter tracts in the brain. There are major discrepancies across different accounts of white matter tract anatomy, hindering our attempts to accurately map the connectivity of the human brain. However, we are often able to clarify the source(s) of these discrepancies through careful consideration of both histological tract-tracing and diffusion-weighted tractography studies. In combination, the advantages and disadvantages of each method permit novel insights into brain connectivity. Ultimately, our synthesis provides an essential reference for neuroscientists and clinicians interested in brain connectivity and anatomy, allowing for the study of the association of white matter's properties with behavior, development, and disorders.We have investigated the reactions of chalcogenoureas derived from N-heterocyclic carbenes, referred to here as [E(NHC)], with halogens. Depending on the structure of the chalcogenourea and the identity of the halogen, a diverse range of reactivity was observed and a corresponding range of structures was obtained. Cyclic voltammetry was carried out to characterise the oxidation and reduction potentials of these [E(NHC)] species; selenoureas were found to be easier to oxidise than the corresponding thioureas. In some cases, a correlation was found between the oxidation potential of these compounds and the electronic properties of the corresponding NHC. The reactivity of these chalcogenoureas with different halogenating reagents (Br2, SO2Cl2, I2) was then investigated, and products were characterised using NMR spectroscopy and single-crystal X-ray diffraction. X-ray analyses elucidated the solid-state coordination types of the obtained products, showing that a variety of possible adducts can be obtained. In some cases, we were able to extrapolate a structure/activity correlation to explain the observed trends in reactivity and oxidation potentials.From classical molecular dynamics simulations, we identify a simple and general predictor of molecular orientation at solid and vapour interfaces of isotropic fluids of disk-like anisotropic particles based on their shape and interaction anisotropy. For a wide variety of inter-particle interactions, temperatures, and substrate types within the range of typical organic semiconductors and their processing conditions, we find remarkable universal scaling of the orientation at the interface with the free energy calculated from pair interactions between close-packed nearest neighbours and an empirically derived universal relationship between the entropy and the shape anisotropy and bulk volume fraction of the fluid particles. The face-on orientation of fluid particles at the solid interface is generally predicted to be the equilibrium structure, although the alignment can be controlled by tuning the particle shape and substrate type, while changing the strength of fluid-fluid interactions is likely to play a less effective role. At the vapour interface, only the side-on structure is predicted, and conditions for which the face-on structure may be preferred, such as low temperature, low interaction anisotropy, or low shape anisotropy, are likely to result in little orientation preference (due to the low anisotropy) or be associated with a phase transition to an anisotropic bulk phase for systems with interactions in the range of typical organic semiconductors. Based on these results, we propose a set of guidelines for the rational design and processing of organic semiconductors to achieve a target orientation at a solid or vapour interface.Reactions of the seven-membered heterocyclic potassium diamidoalumanyl, [KAl(SiNDipp)]2 (SiNDipp = CH2SiMe2NDipp2; Dipp = 2,6-di-isopropylphenyl), with a variety of Cu(I), Ag(I) and Au(I) chloride N-heterocyclic carbene (NHC) adducts are described. The resultant group 11-Al bonded derivatives have been characterised in solution by NMR spectroscopy and, in the case of [SiNDippAl-Au(NHCiPr)] (NHCiPr = N,N'-di-isopropyl-4,5-dimethyl-2-ylidene), by single crystal X-ray diffraction. Although similar reactions of LAgCl and LAuCl, where L is a more basic cyclic alkyl amino carbene (CAAC), generally resulted in reduction of the group 11 cations to the base metals, X-ray analysis of [(CyCAAC)AgAl(SiNDipp)] (CyCAAC = 2-[2,6-bis(1-methylethyl)phenyl]-3,3-dimethyl-2-azaspiro[4.5]dec-1-ylidene) provides the first solid-state authentication of an Ag-Al σ bond. The reactivity of the NHC-supported Cu, Ag and Au alumanyl derivatives was assayed with the isoelectronic unsaturated small molecules, N,N'-di-isopropylcarbodius group 11 alumanyls with N,N'-di-isopropylcarbodiimide indicates that the observed formation of the Cu-N and Ag-N bound isomers do not provide the thermodynamic reaction outcome. In contrast, examination of the CO2-derived reactions, and their potential toward CO extrusion and subsequent carbonate formation, implies that the identity of the co-ligand exerts a greater influence on this aspect of reactivity than the architecture of the diamidoalumanyl anion.Experimental measurements of the thermal effects of the same osmolytes on two different globular proteins, C-reactive protein (CRP) and tumor necrosis factor alpha (TNFα), have shown that quantifying the change in the denaturing temperature leads to some results that are unique to each protein. In order to find osmolyte-dependent parameters that can be applied more consistently from protein to protein, this work considers, instead, the overall free energy change associated with that denaturation using coarse-grained models. Crenolanib order This is enabled by using theoretical fluid equations that take into account the exclusion of water and osmolyte from the volume occupied by the protein in both its native and denatured forms. Assuming ideal geometric models of the two protein states whose sizes are based on the protein's surface area in each form, and taking into account the density of the aqueous osmolyte solution, the free energy change due to the change in geometry can be calculated. The overall change in free energy of the system is found from that quantity and other protein- and osmolyte-specific parameters, which are determined using the experimental concentration and temperature results. We find that these fitted parameters accurately reproduce experimental results and also show consistent patterns from protein to protein. We also consider two different model geometries of the denatured protein and find little impact on the use of one or the other. Defining the effects of the osmolyte in terms of free energy also allows for prediction of overall phase change behavior, including cold denaturation.At temperatures close to absolute zero, the molecular reactions and collisions are dominantly governed by quantum mechanics. Remarkable quantum phenomena such as quantum tunneling, quantum threshold behavior, quantum resonances, quantum interference, and quantum statistics are expected to be the main features in ultracold reactions and collisions. Ultracold molecules offer great opportunities and challenges in the study of these intriguing quantum phenomena in molecular processes. In this article, we review the recent progress in the preparation of ultracold molecules and the study of ultracold reactions and collisions using ultracold molecules. We focus on the controlled ultracold chemistry and the scattering resonances at ultralow temperatures. The challenges in understanding the complex ultracold reactions and collisions are also discussed.Predicting quantum mechanical properties (QMPs) is very important for the innovation of material and chemistry science. Multitask deep learning models have been widely used in QMPs prediction. However, existing multitask learning models often train multiple QMPs prediction tasks simultaneously without considering the internal relationships and differences between tasks, which may cause the model to overfit easy tasks. In this study, we first proposed a multiscale dynamic attention graph neural network (MDGNN) for molecular representation learning. The MDGNN was designed in a multitask learning fashion that can solve multiple learning tasks at the same time. We then introduced a dynamic task balancing (DTB) strategy combining task differences and difficulties to reduce overfitting across multiple tasks. Finally, we adopted gradient-weighted class activation mapping (Grad-CAM) to analyze a deep learning model for frontier molecular orbital, highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy level predictions. We evaluated our approach using two large QMPs datasets and compared the proposed method to the state-of-the-art multitask learning models. The MDGNN outperforms other multitask learning approaches on two datasets. The DTB strategy can further improve the performance of MDGNN significantly. Moreover, we show that Grad-CAM creates explanations that are consistent with the molecular orbitals theory. These advantages demonstrate that the proposed method improves the generalization and interpretation capability of QMPs prediction modeling.

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