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This article, published in the Chemistry of Natural Compounds journal, explores the challenges of extracting polyhydroxyl compounds from medicinal plants and their role in repelling insects. The study focuses on the plant Hylotelephium erythrostictum, which is resilient and adaptable to various weather conditions. The researchers have identified eight polyhydroxyl compounds from this plant, including sarmentosin, sachaloside V, rhodiocyanoside A, lotaustralin, ethyl glucopyranoside, (–)-myrtenyl-α-L-arabinopyranosyl-(1→6)-β-D-glucopyranoside, maltose, and glycerol. The article provides detailed information about the chemical structures and properties of these compounds. The document also discusses the methods used to collect, identify, extract, and partition the plant, as well as the presence of similar compounds in other species of the Rhodiola genus. The research was supported by funding from the National Natural Science Foundation of China and the Doctor of Natural Science Foundation of Yanbian University. [Extracted from the article]

Iron is an extraordinary promoter to impose nickel/cobalt (hydr)oxides as the most active oxygen evolution reaction catalysts, whereas the synergistic effect is actively debated. Here, we unveil that active oxygen species mediate a strong electrochemical interaction between iron oxides (FeOxHy) and the supporting metal oxyhydroxides. Our survey on the electrochemical behavior of nine supporting metal oxyhydroxides (M(O)OH) uncovers that FeOxHy synergistically promotes substrates that can produce active oxygen species exclusively. Tafel slopes correlate with the presence and kind of oxygen species. Moreover, the oxygen evolution reaction onset potentials of FeOxHy@M(O)OH coincide with the emerging potentials of active oxygen species, whereas large potential gaps are present for intact M(O)OH. Chemical probe experiments suggest that active oxygen species could act as proton acceptors and/or mediators for proton transfer and/or diffusion in cooperative catalysis. This discovery offers a new insight to understand the synergistic catalysis of Fe-based oxygen evolution reaction electrocatalysts. The authors systematically and unambiguously correlate the electrocatalytic activity of binary metal oxyhydroxides supported FeOxHy with active oxygen species, and show when and how the active oxygen species are involved during the oxygen evolution reaction process [ABSTRACT FROM AUTHOR]

Soft and stretchable electronics have emerged as highly promising tools for biomedical diagnosis and biological studies, as they interface intimately with the human body and other biological systems. Most stretchable electronic materials and devices, however, still have Young's moduli orders of magnitude higher than soft bio-tissues, which limit their conformability and long-term biocompatibility. Here, we present a design strategy of soft interlayer for allowing the use of existing stretchable materials of relatively high moduli to versatilely realize stretchable devices with ultralow tissue-level moduli. We have demonstrated stretchable transistor arrays and active-matrix circuits with moduli below 10 kPa—over two orders of magnitude lower than the current state of the art. Benefiting from the increased conformability to irregular and dynamic surfaces, the ultrasoft device created with the soft interlayer design realizes electrophysiological recording on an isolated heart with high adaptability, spatial stability, and minimal influence on ventricle pressure. In vivo biocompatibility tests also demonstrate the benefit of suppressing foreign-body responses for long-term implantation. With its general applicability to diverse materials and devices, this soft-interlayer design overcomes the material-level limitation for imparting tissue-level softness to a variety of bioelectronic devices. Stretchable electronics are attractive for a range of biomedical applications, but are challenging to prepare with suitable mechanical properties. Here, the authors report the use of a soft interlayer that allows the development of stretchable electronics with tissue-like material properties. [ABSTRACT FROM AUTHOR]

Unraveling the precise location and nature of active sites is of paramount significance for the understanding of the catalytic mechanism and the rational design of efficient electrocatalysts. Here, we use well-defined crystalline cobalt oxyhydroxides CoOOH nanorods and nanosheets as model catalysts to investigate the geometric catalytic active sites. The morphology-dependent analysis reveals a ~50 times higher specific activity of CoOOH nanorods than that of CoOOH nanosheets. Furthermore, we disclose a linear correlation of catalytic activities with their lateral surface areas, suggesting that the active sites are exclusively located at lateral facets rather than basal facets. Theoretical calculations show that the coordinatively unsaturated cobalt sites of lateral facets upshift the O 2p-band center closer to the Fermi level, thereby enhancing the covalency of Co-O bonds to yield the reactivity. This work elucidates the geometrical catalytic active sites and enlightens the design strategy of surface engineering for efficient OER catalysts. While cobalt-based electrocatalysts demonstrate promising performances for oxygen evolution, active site identification is complicated by concurrent structural changes. Here, authors examine crystalline, well-defined cobalt oxyhydroxide nanomaterials and identify the geometric active sites. [ABSTRACT FROM AUTHOR]

Circular RNAs (circRNAs) have key roles in a variety of neurological diseases, including epilepsy. This objective of this study was to perform the functional exploration and mechanism investigation of circRNA Ubiquilin1 (circUBQLN1) in epilepsy. Epilepsy cell model was established by the treatment of Mg2+-free in human neurons-hippocampal (HN-h) cells. The quantitative real-time polymerase chain reaction (qRT-PCR) was used for the expression analysis of circUBQLN1, linear-UBQLN1, microRNA-155 (miR-155), and sex-determining region Y-box 7 (SOX7). Proliferation detection was completed using Cell Counting Kit-8 (CCK-8) assay. Apoptosis analysis was conducted by flow cytometry and caspase-3 assay. Oxidative stress was assessed through determining the levels of superoxide dismutase (SOD) and malondialdehyde (MDA). Target analysis was performed by dual-luciferase reporter and RNA pull-down assays. SOX7 protein level was examined by Western blot. CircUBQLN1 was downregulated in epilepsy samples and Mg2+-free-induced cell model. Functional analysis in vitro suggested that circUBQLN1 overexpression facilitated proliferation but reduced apoptosis and oxidative stress in Mg2+-free-treated HN-h cells. Target analysis showed that circUBQLN1 acted as a miR-155 sponge and miR-155-targeted SOX7. Moreover, circUBQLN1 could combine with miR-155 to regulate the SOX7 expression. Reverted assays indicated that circUBQLN1 overexpression alleviated the Mg2+-free-induced nerve injury by sponging miR-155, and knockdown of SOX7 abrogated the protective function of in-miR-155 or circUBQLN1 in the Mg2+-free-treated HN-h cells. Our data revealed that circUBQLN1 prevented nerve injury in Mg2+-free-treated HN-h cells by regulating the miR-155/SOX7 axis, showing that circUBQLN1 might be used as a biomolecular target for the treatment of epilepsy. [ABSTRACT FROM AUTHOR]

In our continued phytochemical studies of I O. malacophylla i [[10]-[12]], through an I i -glucosidase activity-guided method, phenolic glycoside constituents were investigated. The ethyl acetate extract was subjected to column chromatography using silica gel (120 ×10 cm, silica gel 75 m), and eluted with dichloromethane-methanol (100:1-1:1) to obtain 11 subfractions (Frs. The NMR featured signals of compound B 6 b that were consistent with the compound B 2 b skeleton. The six compounds, 6 I O i -acetylarbutin ( B 1 b , 17.5 mg), I p i -carboxyphenyl- -D-glycopyranoside ( B 2 b , 8.0 mg), I p i -hydroxyphenyl I i -L-rhamnopyranoside ( B 3 b , 4.0 mg), cissusic acid ( B 4 b , 8.2 mg), arbutin ( B 5 b , 17.5 mg), and I p i -carboxyphenyl-6' I O i -acetate I i -Dglycopyranoside ( B 6 b , 8.4 mg) were first isolated from the ethyl acetate extract of I O. malacophylla i , purifying by RP-18 column chromatography. [Extracted from the article]

The chemical structures of the compounds were determined from the NMR and MS spectra and by comparison with reported values in the literature. The petroleum ether extract (5.3 g) was subjected to a series of silica gel columns (petroleum ether-ethyl acetate, 30:1 to 2:1) to afford 10 compounds on the basis of TLC analysis and a bioassay-guided fractionation. Compd. 2019; 55: 21. 1:CAS:528:DC%2BC1MXmsFeltbc%3D. 10.1007/s10600-019-02606-w 13 Sielinou VT, Vardamides JC, Ali MS, Ahmed Z, Hameed A, Nkengfack AE. In our continuous effort to explore inhibitory -glucosidase ingredients from this plant, we isolate 10 compounds from the petroleum ether extract of I H. erythromosticum i , which is the first report on compounds from the genus I Hylotelephium i , including diethyl 2-hydroxysuccinate ( B 1 b ), triethyl 2-hydroxypropane-1,2,3-tricarboxylate ( B 2 b ), 5-ethoxy-3-(ethoxycarbonyl)- 3-hydroxy-5-oxopentanoic acid ( B 3 b ), methyl -D-xylopyranoside ( B 4 b ), 4-hydroxy-2-methylphenyl- -D-glucopyranoside ( B 5 b ), 6 I O i -acetylarbutin ( B 6 b ), I cis i -caffeic acid ( B 7 b ), scopoletin ( B 8 b ), 24-propylcholesterol ( B 9 b ), and acacetin-7 I O i - -D-glucopyranoside ( B 10 b ). [Extracted from the article]

Skin-like electronics that can adhere seamlessly to human skin or within the body are highly desirable for applications such as health monitoring, medical treatment, medical implants and biological studies, and for technologies that include human-machine interfaces, soft robotics and augmented reality. Rendering such electronics soft and stretchable-like human skin-would make them more comfortable to wear, and, through increased contact area, would greatly enhance the fidelity of signals acquired from the skin. Structural engineering of rigid inorganic and organic devices has enabled circuit-level stretchability, but this requires sophisticated fabrication techniques and usually suffers from reduced densities of devices within an array. We reasoned that the desired parameters, such as higher mechanical deformability and robustness, improved skin compatibility and higher device density, could be provided by using intrinsically stretchable polymer materials instead. However, the production of intrinsically stretchable materials and devices is still largely in its infancy: such materials have been reported, but functional, intrinsically stretchable electronics have yet to be demonstrated owing to the lack of a scalable fabrication technology. Here we describe a fabrication process that enables high yield and uniformity from a variety of intrinsically stretchable electronic polymers. We demonstrate an intrinsically stretchable polymer transistor array with an unprecedented device density of 347 transistors per square centimetre. The transistors have an average charge-carrier mobility comparable to that of amorphous silicon, varying only slightly (within one order of magnitude) when subjected to 100 per cent strain for 1,000 cycles, without current-voltage hysteresis. Our transistor arrays thus constitute intrinsically stretchable skin electronics, and include an active matrix for sensory arrays, as well as analogue and digital circuit elements. Our process offers a general platform for incorporating other intrinsically stretchable polymer materials, enabling the fabrication of next-generation stretchable skin electronic devices. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) have been demonstrated as an effective way to harvest mechanical energy to drive small electronics. The density of triboelectric charges generated on contact surfaces between two distinct materials is a critical factor for dictating the output power. We demonstrate an approach to effectively tune the triboelectric properties of materials by taking advantage of the dipole moment in polarized polyvinylidene fluoride (PVDF), leading to substantial enhancement of the output power density of the TENG. The output voltage ranged from 72 V to 215 V under a constant contact force of 50 N. This work not only provides a new method of enhancing output power of TENGs, but also offers an insight into charge transfer in contact electrification by investigating dipole-moment-induced effects on the electrical output of TENGs. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]