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An electrochemical biosensor based on a water-stable one-dimensional double-chain Cu(II) metal-organic framework (Cu-MOF) directly was constructed for efficiently recognizing l-tyrosine (l-Tyr) in biomimic environments. Cu-MOF [Cu(bpe)(fdc) (H2O)(DMF)]·0.5H2O n (bpe = 1,2-di(4-pyridyl)ethylene, H2fdc = 2,5-furandicarboxylic acid, namely, Cu-1) was synthesized by a hydrothermal method. [https://www.selleckchem.com/products/Eloxatin.html Oxaliplatin] It was characterized by IR, scanning electron microscopy, atomic force microscopy, and PXRD techniques. Cu-1 exhibited extreme solvent and thermal stability as well as excellent electroconductive character. It was coated on a glassy carbon electrode (GCE) surface to prepare an electrochemical biosensor (Cu-1/GCE) which showed preferable biosensing ability toward l-Tyr. This Cu-MOF electrochemical biosensor showed simple operation and high sensitivity toward l-Tyr in the concentration range from 0.01 to 0.09 mM. The detection limit is 5.822 μM. Furthermore, Cu-1/GCE showed extremely excellent selectivity to l-Tyr in a biomimic environment with several amino acid interferents. This new strategy exhibits great potential applications for designing MOFs with excellent electrochemical activity.Structural color has been particularly attractive as it provides a highly promising approach for next-generation color printing. Plasmonic nanostructures have been intensively investigated for color printing, while suffering from intrinsic loss that degrades the quality of the coloration. Dielectric materials have emerged as an alternative because of their high refractive index that enables highly confined optical modes within the nanostructure at the diffraction limit. Here, we demonstrate an all-dielectric nanoring metasurface for coloration. By harnessing the intrinsic nanoring structure design, vivid structural color has been achieved in the visible range. The color gamut is expected to occupy 115% of the standard color space (sRGB) on the chromaticity diagram of the International Commission on Illumination (CIE) 1931 in theory. Our structure can be applied to various complex devices and materials and find potential applications such as displays, information, and art works.Understanding the electronic structure of coordinatively unsaturated transition-metal compounds and predicting their physical properties are of great importance for catalyst design. Bond dissociation energy De and bond length re are two of the fundamental quantities for which good predictions are important for a successful design strategy. In the present work, recent experimentally measured bond energies and bond lengths of VX diatomic molecules (X = C, N, S) are used as a gauge to consider the utility of a number of electronic structure methods. Single-reference methods are one focus because of their efficiency and utility in practical calculations, and multireference configuration interaction (MRCISD) methods and a composite coupled cluster (CCC) method are a second focus because of their potential high accuracy. The comparison is especially challenging because of the large multireference M diagnostics of these molecules, in the range 0.15-0.19. For the single-reference methods, Kohn-Sham density functional theory (KS-DFT) has been tested with a variety of approximate exchange-correlation functionals. Of these, MOHLYP provides the bond dissociation energies in best agreement with experiments, and BLYP provides the bond lengths that are in best agreement with experiments; but by requiring good performance for both the De and re of the vanadium compounds, MOHLYP, MN12-L, MGGA_MS1, MGGA_MS0, O3LYP, and M06-L are the most highly recommended functionals. The CCC calculations include up to connected pentuple excitations for the valence electrons and up to connected quadruple excitations for the core-valence terms; this results in highly accurate dissociation energies and good bond lengths. Averaged over the three molecules, the mean unsigned deviation of CCC bond energies from experimental ones is only 0.4 kcal/mol, demonstrating excellent convergence of theory and experiments.Accumulated pieces of evidence have shown that PI3Kδ plays a critical role in chronic obstructive pulmonary disease (COPD). Using a fragment-hybrid approach, we discovered a potent and selective PI3Kδ inhibitor ( S )-18. In the biochemical assay, ( S )-18 inhibits PI3Kδ (IC50 = 14 nM) with high selectivity over other class I PI3Ks (56∼83 fold). ( S )-18 also achieves good selectivity over other protein kinases in the kinome (S-score (35) = 0.015). In the cell, ( S )-18 selectively and potently inhibits the PI3Kδ-mediated phosphorylation of AKT T308 but not other class I PI3K-mediated signaling. Additionally, ( S )-18 exhibits no apparent inhibitory effect on CYP isoforms except for a moderate effect on CYP2C9. Furthermore, it shows no apparent inhibitory activity against hERG (IC50 &gt; 10 μM). In vivo, ( S )-18 displays favorable PK properties for inhaled delivery and improves lung function in a rodent model of pulmonary inflammation. These results suggest that ( S )-18 might be a new potential therapeutic candidate for COPD.A thorough understanding of native oxides is essential for designing semiconductor devices. Here, we report a study of the rate and mechanisms of spontaneous oxidation of bulk single crystals of ZrS x Se2-x alloys and MoS2. ZrS x Se2-x alloys oxidize rapidly, and the oxidation rate increases with Se content. Oxidation of basal surfaces is initiated by favorable O2 adsorption and proceeds by a mechanism of Zr-O bond switching, that collapses the van der Waals gaps, and is facilitated by progressive redox transitions of the chalcogen. The rate-limiting process is the formation and out-diffusion of SO2. In contrast, MoS2 basal surfaces are stable due to unfavorable oxygen adsorption. Our results provide insight and quantitative guidance for designing and processing semiconductor devices based on ZrS x Se2-x and MoS2 and identify the atomistic-scale mechanisms of bonding and phase transformations in layered materials with competing anions.Bacterial arylmalonate decarboxylase (AMDase) and evolved variants have become a valuable tool with which to access both enantiomers of a broad range of chiral arylaliphatic acids with high optical purity. Yet, the molecular principles responsible for the substrate scope, activity, and selectivity of this enzyme are only poorly understood to date, greatly hampering the predictability and design of improved enzyme variants for specific applications. In this work, empirical valence bond and metadynamics simulations were performed on wild-type AMDase and variants thereof to obtain a better understanding of the underlying molecular processes determining reaction outcome. Our results clearly reproduce the experimentally observed substrate scope and support a mechanism driven by ground-state destabilization of the carboxylate group being cleaved by the enzyme. In addition, our results indicate that, in the case of the nonconverted or poorly converted substrates studied in this work, increased solvent exposure of the active site upon binding of these substrates can disturb the vulnerable network of interactions responsible for facilitating the AMDase-catalyzed cleavage of CO2.