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aureus (+) and Gram-negative E. coli (-).A stereoselective and convenient route has been demonstrated to access (Z)-1,2-diazido alkenes from the corresponding 1,2-diboronic esters via a copper-mediated reaction with sodium azide. Alternately, mono-functionalization was regioselectively carried out with trimethylsilyl azide as an azidation reactant. The in situ conversion of bis-azides to the corresponding bis-triazoles can be readily achieved in the presence of copper sulfate and sodium ascorbate, while the modification of the catalytic system opened a new convenient route to bis-triazolo-pyrazines, a new class of fused heterocycles.Manufacture of uniform, sensitive, and durable microtextured sensing materials is one of the greatest challenges for pressure sensors and electronic skins. Reported in this article is a gold nanoparticle-assembled, 3D-interconnected, graphene microchannel-embedded PDMS (3D GMC-PDMS) film for strain and pressure sensors. The film consists of porous nickel foam with its inner walls coated by multilayer graphene. Embedding in PDMS with etching removal of the Ni yields a 3D GMC-PDMS. Coating the inner walls with Au nanoparticles yields an Au nanoparticle-assembled 3D GMC-PDMS (AuNPs-GMC-PDMS) film, which is useful as an ultrasensitive pressure and strain sensor. This sensor exhibits a wide detection range (∼50 kPa) and ultrahigh sensitivity of 5.37, 1.56, and 0.5 kPa-1 in the ranges of less then 1, 1-10, and 10-50 kPa, respectively. Its lower detection limit is 4.4 Pa, its response time is 20 ms, and its strain factor is up to 15. Comparison of a AuNPs-GMC-PDMS film with a 3D GMC-PDMS film reveals a sensitivity improvement of 40 times in the 0-1 kPa pressure range and a gauge factor of more than 4 times in the 0-30% tensile strain range. The device has broad applications as a traditional or wearable medical sensor.Short-chain fatty acids (SCFAs) are small molecules ubiquitous in nature. In mammalian guts, SCFAs are mostly produced by anaerobic intestinal microbiota through the fermentation of dietary fiber. Levels of microbe-derived SCFAs are closely relevant to human health status and indicative to gut microbiota dysbiosis. However, the quantification of SCFA using conventional chromatographic approaches is often time consuming, thus limiting high-throughput screening tests. Herein, we established a novel method to quantify SCFAs by coupling amidation derivatization of SCFAs with paper-loaded direct analysis in real time mass spectrometry (pDART-MS). Remarkably, SCFAs of a biological sample were quantitatively determined within a minute using the pDART-MS platform, which showed a limit of detection at the μM level. This platform was applied to quantify SCFAs in various biological samples, including feces from stressed rats, sera of patients with kidney disease, and fermentation products of metabolically engineered cyanobacteria. Significant differences in SCFA levels between different groups of biological practices were promptly revealed and evaluated. As there is a burgeoning demand for the analysis of SCFAs due to an increasing academic interest of gut microbiota and its metabolism, this newly developed platform will be of great potential in biological and clinical sciences as well as in industrial quality control.Ion channels are often targeted by toxins or other ligands to modify their channel activities and alter ion conductance. PF-477736 clinical trial between toxins and ion channels could result in changes in membrane insertion depth for residues close to the binding site. Paramagnetic solid-state nuclear magnetic resonance (SSNMR) has shown great potential in providing structural information on membrane samples. We used KcsA as a model ion channel to investigate how the paramagnetic effects of Mn2+ and Dy3+ ions with headgroup-modified chelator lipids would influence the SSNMR signals of membrane proteins in proteoliposomes. Spectral comparisons have shown significant changes of peak intensities for the residues in the loop or terminal regions due to paramagnetic effects corresponding to the close proximity to the membrane surface. Hence, these results demonstrate that paramagnetic SSNMR can be used to detect surface residues based on the topology and membrane insertion properties for integral membrane proteins.As a star ligand, the construction of coordination polymers (CPs) based on tetrakis(4-carboxyphenyl)ethylene (H4TCPE) has drawn much attention, due to not only the various coordination configurations but also the intriguing chromophore feature causing aggregation-induced emission (AIE). Herein, by the solvothermal reaction of H4TCPE as connected nodes with lanthanide La(III) salts, the first example of the La(III)-TCPE-based CP (1) has been obtained. The structural analyses indicate that 1 exhibits a 3D framework connected by the sharing carboxylate groups with two kinds of 1D rhombic channels when viewed along the c direction. The photophysical properties of 1 have been explored by luminescence, photoluminescence decay, and quantum yield in the solid state. 1 shows strong luminescence in tetrahydrofuran that was attributed to a "pseudo-AIE process" and sensitive and selective sensing activity of Fe3+ toward metal ions via the obvious luminescent quenching. The sensing mechanism has been investigated and reveals a synergetic effect of the competitive absorption and weak interactions between 1 and Fe3+. #link# Moreover, the high porosity, multiple conjugated π-electrons within the tetrakis(4-carboxyphenyl)ethylene backbone, and the uncoordinated carboxyl oxygen sites in this material also provide the capacity for iodine adsorption. The adsorption experiments indicate that 1 could efficiently remove almost complete I2 from the cyclohexane solution after 24 h contact time with an adsorption capacity of 690 mg/g toward I2.The development of a photoinduced, highly diastereo- and enantioselective [3 + 2]-cycloaddition of N-cyclopropylurea with α-alkylstyrenes is reported. This asymmetric radical cycloaddition relies on the strategic placement of urea on cyclopropylamine as a redox-active directing group (DG) with anion-binding ability and the use of an ion pair, comprising an iridium polypyridyl complex and a weakly coordinating chiral borate ion, as a photocatalyst. The structure of the anion component of the catalyst governs reactivity, and pertinent structural modification of the borate ion enables high levels of catalytic activity and stereocontrol. This system tolerates a range of α-alkylstyrenes and hence offers rapid access to various aminocyclopentanes with contiguous tertiary and quaternary stereocenters, as the urea DG is readily removable.