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It was observed that 2-Sc3+ was ca. 3200 times more reactive toward the OAT reaction compared to 2. Hammett analysis of 2 exhibited a V-shaped plot, indicating a change of the reaction mechanism upon going from electron-rich to electron-deficient Ar3P substrates. In contrast, 2-Ca2+ and 2-Sc3+ showed an electrophilic nature toward the OAT reaction, thus demonstrating the role of the Lewis acid in controlling the OAT mechanism. The hydrogen-atom abstraction reaction of 2 and 2-Mn+ adducts with 1-benzyl-1,4-dihydronicotinamide was investigated, and it was observed that the rate of reaction did not vary considerably with the Lewis acidity of Mn+ ions. On the basis of Eyring analysis of 2 and 2-Mn+ adducts, we hypothesized an entropy-controlled hydrogen-atom-transfer reaction for 2-Sc3+, which is different from the reaction mechanism of 2 and 2-Ca2+.Asarum heterotropoides extracts showed strong antibacterial activity against selected phytopathogenic bacteria. Bioguided isolation was conducted to obtain 11 phenanthrene derivatives (1-11), 4 phenylpropanoids (12-15), a flavonoid (16), and a steroid (17), including a new phenanthrene derivative (1). In vitro bioassay results showed that phenanthrene derivatives are the main active components of A. heterotropoides extracts. The new compound aristoloxazine C (1) was found to exhibit outstanding antibacterial activity against Ralstonia solanacearum, Xanthomonas oryzae, Erwinia carolovora, Pseudomonas syringae, and Xanthomonas axonopodis, with MIC values of 0.05, 2.5, 2.5, 5, and 6.25 μg/mL, respectively. These values were significantly higher than that of the positive control, streptomycin sulfate. mTOR target Aristoloxazine C (1) also demonstrated an excellent control effect on tobacco bacterial wilt. Physiological and biochemical experiments combined with electron microscopy showed that the antibacterial activity of aristoloxazine C (1) was primarily related to the destruction of the bacterial cell wall structure. Thus, aristoloxazine C (1) may have the potential to be used as a template for the development of new bactericides or as a probe for the discovery of new antimicrobial targets.Trifolium pratense L. (red clover) is a popular botanical supplement used for women's health. Irilone isolated from red clover previously demonstrated progestogenic potentiation activity. In this study, irilone enhanced progesterone signaling was determined to not occur due to post-translational phosphorylation or by reducing progesterone receptor (PR) protein levels but instead increased PR protein levels in T47D breast cancer cells, which could be blocked by estrogen receptor (ER) antagonists, suggesting an ER dependent effect. Further, irilone increased luciferase activity from a hormone responsive element in a cell line that lacked ER and PR but expressed the glucocorticoid receptor (GR). A siRNA knockdown of GR in Ishikawa PR-B endometrial cancer cells reduced irilone's ability to enhance progesterone signaling. In an ovariectomized CD-1 mouse model, irilone did not induce uterine epithelial cell proliferation. The mechanism of action of irilone gives insight into PR crosstalk with other steroid hormone receptors, which can be important for understanding botanicals that are used for women's health.Methods for producing DNA SAM-based sensors with improved thermal stability and control over the homogeneity of low DNA probe density will enable advanced sensor development. The thermal stability of low-coverage DNA SAMs was studied for surfaces prepared using potential-assisted thiol exchange (Edep) and compared to DNA SAMs prepared without control over the substrate potential (OCPdep). Both surface preparation methods were studied using in situ fluorescence microscopy and electrochemistry with fluorophore or redox-modified DNA SAMs on a single-crystal gold bead electrode. Fluorescence microscopy showed that the influence of the underlying surface crystallography was important in both cases. The highest thermal stability was realized for square or rectangular surface atomic structure (e.g., surfaces from 110 to 100). The 111 and related surfaces were the least thermally stable. The low DNA coverage surfaces prepared by Edep had better thermal stability and higher DNA probe mobility as compared to OCPdep-prepared surfaces with the similar coverage. These results were correlated with methylene blue redox-tagged DNA probes, which directly measured the average DNA coverage. Both methods indicated that Edep DNA SAMs were more uniformly distributed across the electrode surface, while the surfaces prepared via OCPdep assembled into clusters with reduced mobility. The potential-assisted thiol-exchange approach to preparing low-coverage DNA SAMs was shown to quickly create modified surfaces that were consistent, had mobility characteristics which should yield superior DNA hybridization efficiencies, and having greater thermal stability which will translate into a longer shelf-life.Protein adsorption to surfaces is at the heart of numerous technological and bioanalytical applications, but sometimes, it is also associated with medical risks. To deepen our insights into processes involving layers of surface-adsorbed proteins, high-resolution structural information is essential. Here, we use standing-wave X-ray fluorescence (SWXF) in combination with an optimized liquid-cell setup to investigate the underwater conformation of the random-coiled phosphoprotein β-casein adsorbed to hydrophilic and hydrophobized solid surfaces. The orientation of the protein, as determined through the distributions of sulfur and phosphorus, is found to be sensitive to the chemical nature of the substrate. While no preferred orientations are observed on hydrophobized surfaces, on hydrophilic Al oxide, β-casein is adsorbed as a diblock copolymer with the phosphorylated domain I attached to the surface. Our results demonstrate that targeting biologically relevant chemical elements with SWXF enables a detailed investigation of biomolecular layers under near-physiological conditions.A noninvasive fiber material-based wearable electrochemical sensor to continuously monitor the glucose level in sweat is highly desirable for smart fabrics for personal diabetes management. To achieve it, the key challenge is to construct fibers with high stretchability and excellent electrochemical performance. Herein, a highly stretchable Ni-Co metal-organic framework/Ag/reduced graphene oxide/polyurethane (Ni-Co MOF/Ag/rGO/PU) fiber-based wearable electrochemical sensor is fabricated for monitoring the glucose level in sweat continuously with high sensitivity and accuracy. The rGO/PU fiber was simply produced by an improved wet spinning technology, and the Ni-Co MOF nanosheet was coated on its surface to prepare the Ni-Co MOF/Ag/rGO/PU (NCGP) fiber electrode. The Ni-Co MOF has a large specific surface area and high catalytic activity, which enables the fiber sensors with good electrochemical performance with a high sensitivity of 425.9 μA·mM-1·cm-2 and a wide linear range of 10 μM-0.66 mM. More importantly, the NCGP fiber electrode also shows extremely high stretching and bending stability under mechanical deformation. Also, the NCGP fiber electrode has high selectivity and long-time storage stability. Moreover, the NCGP fiber-based three-electrode system was sewn with an absorbent fabric and fixed on a stretchable polydimethylsiloxane film substrate to form a nonenzymatic sweat glucose wearable sensor, which realized real-time monitoring of glucose in human sweat with high accuracy. This indicates that our designed NCGP fiber can be used as a wearable electrochemical sensor for the bio-diagnostics of body sweat.Advances in single-cell level profiling of the proteome require quantitative and versatile platforms, especially for rare cell analyses such as circulating tumor cell (CTC) profiling. Here we demonstrate an integrated microfluidic chip that uses magnetic nanoparticles to capture single tumor cells with high efficiency, permits on-chip incubation, and facilitates in situ cell-surface protein expression analysis. Combined with phage-based barcoding and next-generation sequencing technology, we were able to monitor changes in the expression of multiple surface markers stimulated in response to CTC adherence. Interestingly, we found fluctuations in the expression of Frizzled2 (FZD2) that reflected the microenvironment of the single cells. This platform has a high potential for in-depth screening of multiple surface antigens simultaneously in rare cells with single-cell resolution, which will provide further insights regarding biological heterogeneity and human disease.Raman spectral libraries specific to microplastics demonstrated improved spectral matching results when weathered plastics and a variety of particle colors and morphologies were included. Here, we explore if this is true for Fourier transform infrared (FTIR) spectroscopy as well. We present two novel databases specific to microplastics using attenuated total reflection (μATR-FTIR) (1) an FTIR library of plastic particles (FLOPP), containing 186 spectra from common plastic items, across 14 polymer types and (2) an FTIR library of plastic particles sourced from the environment (FLOPP-e), containing 195 spectra across 15 polymer types. Both libraries include particles from a variety of sources, morphologies, and colors. We demonstrate the applicability of these libraries for microplastics research by comparing spectral match results from two microplastic datasets. For this, we use different combinations of libraries including commercially available reference libraries, an open-access polymer library, and FLOPP and FLOPP-e. Among tests, the greatest mean HQI result was achieved when the greatest number of libraries was included. This work demonstrates that spectral libraries specific to plastic particles found in the environment improve the accuracy of spectral matching and are best used in combination with commercial libraries containing chemical components that are commonly found within plastics and other anthropogenic particles. Multivariate principal component analyses of FLOPP and FLOPP-e spectra confirmed differences among polymer types and higher variation in principal component scores among weathered particles, but no patterns were observed among particle colors or morphologies. These results demonstrate that ATR-FTIR analyses are sensitive to weathering of plastics but not to particle color and morphology.Liquid phase exfoliation (LPE) is a popular method to create dispersions of two-dimensional nanosheets from layered inorganic van der Waals crystals. Here, it is applied to orthorhombic and triclinic single crystals of the organic semiconductor rubrene with only noncovalent interactions (mainly π-π) between the molecules. Distinct nanorods and nanobelts of rubrene are formed, stabilized against aggregation in aqueous sodium cholate solution, and isolated by liquid cascade centrifugation. Selected-area electron diffraction and Raman spectroscopy confirm the crystallinity of the rubrene nanorods and nanobelts while the optical properties (absorbance, photoluminescence) of the dispersions are similar to rubrene solutions due to their randomized orientations. The formation of these stable crystalline rubrene nanostructures with only a few molecular layers by LPE confirms that noncovalent interactions in molecular crystals can be strong enough to enable mechanical exfoliation similar to inorganic layered materials.