Printed electronics on elastomer substrates have found wide applications in wearable devices and soft robotics. For everyday usage, additional requirements exist for the robustness of the printed ...flexible electrodes, such as the ability to resist scratching and damage. Therefore, highly robust electrodes with self‐healing, and good mechanical strength and stretchability are highly required and challenging. In this paper, a cross‐linking polyurea using polydimethylsiloxane as the soft segment and dynamic urea bonds is prepared and serves as a self‐healing elastomer substrate for coating and printing of silver nanowires (AgNWs). Due to the dynamic exchangeable urea bond at 60 °C, the elastomer exhibits dynamic exchange of the cross‐linking network while retaining the macroscopic shape. As a result, the AgNWs are partially embedded in the surface of the elastomer substrate when coated or printed at 60 °C, forming strong interfacial adhesion. As a result, the obtained stretchable electrode exhibits high mechanical strength and stretchability, the ability to resist scratching and sonication, and self‐healing. This strategy can be applied to a variety of different conducting electrode materials including AgNWs, silver particles, and liquid metal, which provides a new way to prepare robust and self‐healing printed electronics.
A concept involving preparing stretchable, robust, and self‐healing electrodes via a direct surface printing on a polyurea elastomer is developed in this work. Taking advantage of the dynamic polyurea's kinetic chain movement at an elevated temperature, variable conductive nano‐fillers can be self‐embedded into the elastomer's surface without shape changing, exhibiting high significance in designing both robust and self‐healing electrodes.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
MicroRNA-9 (miR-9) is involved in inflammatory reaction in atherosclerosis; however, its function and regulatory mechanisms remain unclear. We aimed to uncover the exact roles of miR-9 and downstream ...signaling pathways using in vitro human atherosclerosis models.
We used oxidized low-density lipoprotein (oxLDL)-stimulated human THP-1 derived macrophages, oxLDL-stimulated human primary peripheral blood monocytes and lipopolysaccharides (LPS) or Alum-stimulated human THP-1 derived macrophages as in vitro atherosclerosis inflammation models. Transient transfection of over-expression vectors, small interference RNAs (siRNAs) or antisense oligonucleotides was used to regulate intracellular protein or miR-9 levels. Cell responses and signal transduction were detected by multiple assays including Western blotting, enzyme-linked immunosorbent assay (ELISA) and luciferase reporter assay.
MiR-9 inhibited while anti-miR-9 antisense oligonucleotides induced interleukin-1 beta (IL-1β) and NLRP3 inflammasome activation in all in vitro models. Janus kinase 1 (JAK1) and matrix metalloproteinase 13 (MMP-13) were identified as the target genes of miR-9. In oxLDL-stimulated human THP-1 derived macrophages, knockdown of JAK1 by siRNA blocked the phosphorylation of signal transducer and activator of transcription 1 (STAT1) and mimicked the effects of miR-9. In the same model, JAK1 knockdown blocked the phosphorylation of NF-κB p65 in the nuclei and the phosphorylation of NF-κB IκBα in the cytoplasm.
Our study demonstrated that miR-9 could inhibit activation of the NLRP3 inflammasome and attenuate atherosclerosis-related inflammation, likely through the JAK1/STAT1 signaling pathway. Therefore, miR-9 may serve as a potential therapeutic target for atherosclerosis.
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•A photoelectrochemical sensor was developed for the “signal-on” analysis of Hg2+.•Bead chain-like Ag2S were integrated with ZnS to be coated onto the ITO electrodes.•Ag2S and ZnS ...were utilized separately as the sensitizer and recognition probe.•Hg2+ can conduct a Zn-to-Hg exchange to form HgS/ZnS@Ag2S heterojunction.•This sensor can facilitate the detection of Hg2+ with concentrations down to 1.0 pM.
A visible-light-driven photoelectrochemical (PEC) sensor has been developed for the “signal-on” analysis of Hg2+ by the synergetic combination of low-bandgap Ag2S and wide-bandgap ZnS quantum dots (QDs). Ag2S QDs were synthesized with bead-chain-like structure by the self-assembly route and further covalently bound with ZnS QDs to be coated onto the indium tin oxide (ITO) electrodes. It was discovered that the ZnS@Ag2S-modified electrodes could display the visible-light-driven PEC behavior, of which Ag2S and ZnS QDs could act as the PEC sensitizer and Hg2+-recognition probe, respectively. More importantly, the photocurrent responses of the developed electrodes could be specifically turned on in the presence of Hg2+ under the visible-light irradiation, presumably due to that Hg2+ might conduct a Zn-to-Hg exchange on ZnS QDs to trigger the formation of HgS/ZnS@Ag2S heterojunction towards the enhanced electron-hole separation. The as-prepared PEC sensor could facilitate the detection of Hg2+ with concentrations ranging from 0.010–1000 nM, with a detection limit of about 1.0 pM. Besides, the feasibility of practical applications of the developed PEC analysis strategy was verified by probing Hg2+ in environmental water samples. Such a visible-light-driven PEC detection platform with the unique “turn-on” signal output may promise for the extensive applications for Hg2+ evaluation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Two-dimensional (2D) valleytronics materials have garnered significant attention due to great potential for information encoding and processing. Here, we investigate the strain effect on the valley ...and topological properties of a novel septuple-layer FeO2Si2N2 monolayer by employing the first-principles calculations. The monolayer is affirmed to be a stable ferrovalley semiconductor with in-plane magnetization and high Curie transition temperature (156 K). Further, by applying the compressive strain from −3.24 to −3.4%, the magnetization of the monolayer can be tuned from in-plane to out-of-plane direction, and consequently, the monolayer exhibits topological nontrivial valley state with valley polarization due to the breaking of inversion and time-reversal symmetry, and higher Curie temperature (213 K) due to the enhanced superexchange interaction between Fe and O atoms. Thus, the long-sought valley-polarized quantum anomalous Hall (VQAH) effect can be realized in higher Curie temperature in FeO2Si2N2 monolayer by applying the appropriate compressive strain.
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•FeO2Si2N2 monolayer is a FM semiconductor with high Tc of 156 K and MAE of 0.95 meV.•The MAE can be flipped from in-plane to out-of-plane under −3.24% to −3.4% strain.•The reversal of magnetization direction indicates the emergence of valley polarization.•The valley-polarized quantum anomalous Hall effect can be observed under strain.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•A new green solvent system, glycolic acid pretreatment, has been discovered.•The separation of hemicellulose was highly selective.•The depolymerization and repolymerization of lignin ...were inhibited.•The separation rate of hemicellulose was as high as 65.08%.•The recovery rate of glycolic acid was as high as 91%.
Glycolic acid has chemical properties similar to those of formic acid. Therefore, similar to formic acid pretreatment, glycolic acid pretreatment has the separation effect of hemicellulose. In this study, eucalyptus hemicellulose was effectively separated by glycolic acid pretreatment. The effects of glycolic acid concentration, temperature and time on the separation of cellulose, hemicellulose and lignin were investigated. The optimum conditions were acid concentration 5.40%, temperature 140 °C, time 3.0 h. The highest yield of xylose was 56.72%. The recovery rate of glycolic acid was 91%. Compared to formic acid, the yield of xylose increased to 10.33% while that of lignin decreased to 11.08%. It showed high selectivity for hemicellulose separation, yielding 65.48% hemicellulose with 72.08% purity. The depolymerization and repolymerization of lignin were inhibited. The integrity of the cellulose structure was preserved. It provides theoretical support for the fractional separation and high-value transformation of lignocellulosic biomass.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Tenacissoside H (TEH), which has anti-inflammatory and anti-tumor effects, is a major active ingredient extracted from the stem of Marsdenia tenacissima. However, the effect of TEH on hepatocellular ...carcinoma (HCC) as well as the underlying mechanisms are still indistinct. Presently, HCC cells (including Huh-7 and HepG2) were dealt with different concentrations of TEH. The proliferation and apoptosis of HCC cells were determined via Cell Counting Kit-8 (CCK8) assay and flow cytometry. In addition, Western blot was conducted to evaluate the expressions of autophagy—and apoptosis-related proteins. Tissue immunofluorescence was carried out to evaluate LC3B expression in the tumor tissues. The data showed that TEH suppressed the growth of HCC cells in a concentration-dependent manner. Besides, TEH enhanced radiosensitivity and promoted the apoptosis of HCC cells. Moreover, the mRNA and protein levels of autophagy-related genes (LC3-II/LC2-I, ATG5, Beclin-1) were significantly promoted by TEH. Mechanistically, TEH attenuated the activation of PI3K/Akt/mTOR signaling pathway. However, inhibition of PI3 K pathway abolished the anti-tumor effects of TEH in HCC cells. Collectively, this study suggested that TEH increases the radiosensitivity of HCC cells via inducing autophagy and apoptosis through downregulating PI3K/Akt/mTOR signaling pathway.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Magnetic topological insulators (Chern insulators) have been extensively sought since quantum anomalous Hall effect (QAHE) was experimentally verified. Here, we employ first-principles calculations ...to predict a kagome lattice Zn2N3 monolayer to be an intrinsic magnetic topological insulator which makes QAHE to be realized. The stable Zn2N3 monolayer is shown to exhibit a large band gap of 3.75 eV in a spin channel and a well known Weyl point near the Fermi level with the Fermi velocity of about 4.2 × 105 m s−1 in the other spin channel. Further taking into account the spin–orbit coupling (SOC), the system opens a band gap of 4.3 meV at the Fermi level, and the opening of the band gap brings about a surge in the Berry curvature, which transforms the system into a topological non-trivial state. In addition, the Zn2N3 belongs to the ferromagnetic ground state with out of plane magnetization, and the Curie temperature (Tc) is estimated to be 168 K by Monte Carlo simulation. Moreover, the tight-binding (TB) model is established to verify the topological properties with the calculated Chern number C = 1, anomalous Hall conductance (AHC) σxy=e2/h, and a dissipation-free chiral edge state. Thus, the kagome Zn2N3 monolayer could be a potential candidate for achieving QAHE and low-power consumption spintronic devices.
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•The 2D Kagome lattice Zn2N3 is confirmed to be an intrinsic magnetic topological insulator.•The linear band crossings with the Weyl point was found at the Fermi level, which is mainly contributed by the Pz orbitals of N atoms.•The Zn2N3 holds the ferromagnetic ground state with out of plane magnet moment, and the Currie temperature is about 168 K.•Realization of quantum anomalous Hall effect in the Zn2N3 is proved to be feasible.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Ferromagnetic semiconductors with coexisting ferroelectric and ferrovalley polarizations are highly desirable for next-generation electronic devices and have rarely been discovered till date. Herein, ...we employ the first-principles calculations to identify the stable two-dimensional semiconductors ReAlGe2X6 (X = S, Se) to concurrently exhibit ferroelectric (FE), ferromagnetic (FM), and ferrovalley (FV) polarizations. The FE derives from the spontaneous spatial mirror ( P ) asymmetry induced by a vertical displacement of Ge–Ge dimers. The FM arises from the Re–X–Ge–X–Re supersuperexchange interactions, which enhances the Curie temperature (T C) up to 192 and 180 K for S and Se systems, respectively. Furthermore, due to the strong spin–orbit coupling of d shell of Re atoms, ReAlGe2X6 (X = S, Se) capture a remarkable perpendicular magnetocrystalline anisotropy energy of 4.86 and 3.79 meV, which breaks time-inversion ( T ) symmetry, and consequently, posse the giant FV polarization of 280 and 260 meV, as well as polarized Berry curvature and circularly light absorption, which notably enables exceptional anomalous valley Hall and circular dichroism effects. The tuning properties of the valley and magnetic states are further characterized by strain.
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IJS, KILJ, NUK, PNG, UL, UM
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