13 research outputs found
Amelioration of Atherosclerosis by lycopene is linked to the modulation of gut microbiota dysbiosis and related gut-heart axis activation in high-fat diet-fed ApoEâ/â mice
Abstract Background Interplay between gut microbiota and heart, termed âgut-heartâ axis, has a crucial role in the pathogenesis of atherosclerosis. Our previous study showed that lycopene possesses anti-inflammatory and anti-atherosclerotic effects, but its link to the gut microbiota is poorly understood. Herein, we surmised that lycopene could regulate the gut microbiota, exert anti-atherosclerotic effect by regulating the âgut-heartâ axis. Methods Male ApoEâ/â mice were fed a high-fat diet (HFD) with or without lycopene (0.1% w/w) for 19 weeks. Gut microbiota was analyzed by 16 S rRNA sequencing, the protein levels of zonula occludens-1 (ZO-1), occludin, toll-like receptor 4 (TLR4) and phospho-nuclear factor-ÎșB (NF-ÎșB) p65 were measured by Western blotting, the levels of serum inflammatory factors including monocyte chemotactic protein 1 (MCP-1), tumor necrosis factor-α (TNF-α), interleukin-1ÎČ (IL-1ÎČ), and IL-6 were assayed using ELISA kits. Also, the concentrations of serum lipopolysaccharide (LPS), D-lactic acid (D-LA) and diamine peroxidase (DAO) were measured through ELISA method. Results The aortic sinus sections revealed that lycopene supplementation significantly reduced the extent of atherosclerotic lesions and inhibited atherosclerosis development caused by HFD. The analysis of gut microbiota showed that lycopene reduced the ratio of Firmicutes/Bacteroides and increased the relative abundance of Verrucomicrobia, Akkermansia and Alloprevotella, which were related to elevated intestinal barrier function and reduced inflammation. Moreover, lycopene up-regulated the expression of intestinal ZO-1 and occludin and decreased serum LPS, D-LA and DAO levels. In addition, lycopene inhibited the expression of TLR4 and phospho-NF-ÎșB p65 in aortic sinus plaque, serum MCP-1, TNF-α, IL-1ÎČ, and IL-6 levels were also lowered by lycopene treatment. Conclusions Our results indicated the protective effect of lycopene against atherosclerosis induced by HFD and further revealed that its mechanism might be its prebiotic effect on maintaining gut microbiota homeostasis and improving intestinal barrier function, consequently reducing serum LPS-triggered inflammatory response in the heart
On demand shape memory polymer via light regulated topological defects in a dynamic covalent network
Stimuli-responsive soft materials are of interest for a range of applications. Here, the authors report on the use of light triggered catalysts to control topological defect driven isomerization of polymer networks and demonstrate application in shape memory polymers
Characterization of Intracellular Structure Changes of Microcystis under Sonication Treatment by Polarized Light Scattering
Cyanobacterial bloom is one of the most urgent global environmental issues, which eventually could threaten human health and safety. Sonication treatment (ST) is a potential effective method to control cyanobacteria blooms in the field. Currently, the bottleneck of extensive application of ST is the difficulty to estimate the ST effect on the cyanobacterial cells and then determine suitable ST times in the field. In this study, cyanobacterial Microcystis samples sonicated at different times were first measured by a spectrophotometer to calculate the removal efficiency of Microcystis cells. Additionally, they were observed by TEM to reveal the intracellular structure changes of the cells. Then the samples were measured by an experimental setup based on polarized light scattering to measure the polarization parameters. Experimental results indicated that the polarization parameters can effectively characterize the intracellular structural changes of Microcystis cells with different ST times, which is quite consistent with the results for removal efficiency and TEM images. Further, the optimal ST time can be inferred by the polarization parameters. These results demonstrate that polarized light scattering can be a potentially powerful tool to explore suitable times for sonication treatment of cyanobacteria blooms
Wavelength-tunable picosecond soliton fiber laser with topological insulator : Bi2Se3 as a mode locker
Based on the open-aperture Z-scan measurement, we firstly uncovered the saturable absorption property of the topological insulator (TI): Bi2Se3. A high absolute modulation depth up to 98% and a saturation intensity of 0.49 GWcmâ2 were identified. By incorporating this novel saturable absorber material into an erbium-doped fiber laser, wavelength tunable soliton operation was experimentally demonstrated. Our result indicates that like the atomic layer graphene, the topological insulator Bi2Se3 could also operate as an effective saturable absorber for the passive mode locking of lasers at the telecommunication band.Published versio
Third order nonlinear optical property of Bi2Se3
The third order nonlinear optical property of Bi2Se3, a kind of topological insulator (TI), has been investigated under femto-second laser excitation. The open and closed aperture Z-scan measurements were used to unambiguously distinguish the real and imaginary part of the third order optical nonlinearity of the TI. When excited at 800 nm, the TI exhibits saturable absorption with a saturation intensity of 10.12 GW/cm2 and a modulation depth of 61.2%, and a giant nonlinear refractive index of 10 -14 m2/W, almost six orders of magnitude larger than that of bulk dielectrics. This finding suggests that the TI: Bi2Se 3 is indeed a promising nonlinear optical material and thus can find potential applications from passive laser mode locker to optical Kerr effect based photonic devices.Published versio
Broadband spatial self-phase modulation and ultrafast response of MXene Ti3C2Tx (T=O, OH or F)
Two-dimensional layered materials (2DLM) have become the subject of intensive research in various applications such as electronics, photonics and optoelectronics due to their unique physical properties. As a new class of 2DLM, MXenes have attracted great interest due to their superior performance in a wide variety of applications such as batteries, supercapacitors, catalysts, electronics and optics. Here, we have investigated the broadband spatial self-phase modulation (SSPM) and ultrafast response of the MXene Ti3C2Tx (T=O, OH or F) experimentally. The MXene Ti3C2Tx exhibited the broadband nonlinear optical response via SSPM from 400 nm to ~1 ÎŒm under the ultrafast laser excitation, and ultrafast carrier characteristics with an ultrafast recovery time with femtosecond transient absorption spectroscopy. The experimental results have shown that the MXenes have the broadband nonlinear optical response, which can lay a foundation for the application prospect for the MXene-based ultrafast optoelectronic devices
Correction: A disorder-free conformation boosts phonon and charge transfer in an electron-deficient-core-based non-fullerene acceptor (vol 8, pg 8566, 2020)
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Fused benzothiadiazole : a building block for n-type organic acceptor to achieve high-performance organic solar cells
Narrow bandgap n-type organic semiconductors (n-OS) have attracted great attention in recent years as acceptors in organic solar cells (OSCs), due to their easily tuned absorption and electronic energy levels in comparison with fullerene acceptors. Herein, a new n-OS acceptor, Y5, with an electron-deficient-core-based fused structure is designed and synthesized, which exhibits a strong absorption in the 600â900 nm region with an extinction coefficient of 1.24 Ă 105 cmâ1, and an electron mobility of 2.11 Ă 10â4 cm2 Vâ1 sâ1. By blending Y5 with three types of common medium-bandgap polymers (J61, PBDB-T, and TTFQx-T1) as donors, all devices exhibit high short-circuit current densities over 20 mA cmâ2. As a result, the power conversion efficiency of the Y5-based OSCs with J61, TTFQx-T1, and PBDB-T reaches 11.0%, 13.1%, and 14.1%, respectively. This indicates that Y5 is a universal and highly efficient n-OS acceptor for applications in organic solar cells
Fused Benzothiadiazole: A Building Block for nâType Organic Acceptor to Achieve HighâPerformance Organic Solar Cells
Narrow bandgap n-type organic semiconductors (n-OS) have attracted great attention in recent years as acceptors in organic solar cells (OSCs), due to their easily tuned absorption and electronic energy levels in comparison with fullerene acceptors. Herein, a new n-OS acceptor, Y5, with an electron-deficient-core-based fused structure is designed and synthesized, which exhibits a strong absorption in the 600â900 nm region with an extinction coefficient of 1.24 Ă 105 cmâ1, and an electron mobility of 2.11 Ă 10â4 cm2 Vâ1 sâ1. By blending Y5 with three types of common medium-bandgap polymers (J61, PBDB-T, and TTFQx-T1) as donors, all devices exhibit high short-circuit current densities over 20 mA cmâ2. As a result, the power conversion efficiency of the Y5-based OSCs with J61, TTFQx-T1, and PBDB-T reaches 11.0%, 13.1%, and 14.1%, respectively. This indicates that Y5 is a universal and highly efficient n-OS acceptor for applications in organic solar cells