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1.
Nanotechnology ; 32(9): 095403, 2021 Feb 26.
Article in English | MEDLINE | ID: mdl-33203815

ABSTRACT

The development of a biodegradable cellulose-based separator with excellent performance has been of great research significance and application potential for the green development of supercapacitors. Herein, the regenerated porous cellulose/Polyvinyl alcohol films (CP-10, CP-15, CP-20, CP-25) with different mass ratio were successfully fabricated by a simple blending and phase inversion process. Their electrochemical properties as separators in assembled supercapacitor were evaluated. Fourier transform infrared spectroscopy and x-ray diffraction analysis indicate that intermolecular and intramolecular hydrogen bonding existed between cellulose and polyvinyl alcohol of the CP films. Compared with other CP films, the CP-20 film shows higher mechanical strength (28.02 MPa), better wettability (79.06°), higher porosity (59.69%) and electrolyte uptake (281.26 wt%). These properties of CP-20 are expected to show better electrochemical performance as separator. Indeed, the electrochemical tests, including electrochemical impedance spectroscopy, cyclic voltammetry, galvanostatic charge discharge, demonstrate that the SC-20 capacitor (with CP-20 as separator) shows the lowest equivalent series resistance of 0.57 Ω, the highest areal capacitance of 1.98 F cm-2 at 10 mV s-1, specific capacitance of 134.41 F g-1 and charge-discharge efficiency of 98.62% at 1 A g-1 among the four capacitors with CP films as separators. Comparing the assembled SC-40 and SC-30 with two commercial separators (TF4040 and MPF30AC) and SC-PVA with Polyvinyl alcohol (PVA) separator, the CV and GCD curves of SC-20 maintain the quasi rectangular and symmetrical triangular profiles respectively at different scan rates in potential window of 0-1 V. SC-20 exhibits the highest value of 28.24 Wh kg-1 at 0.5 A g-1 with a power density of 0.26 kW kg-1, and 13.41 Wh kg-1 at 10 A g-1 with a power density of 6.04 kW kg-1. SC-20 also shows the lowest voltage drop and the highest areal and specific capacitance. Moreover, SC-20 maintains the highest value of 86.81% after 4000 cycles compared to 21.18% of SC-40, 75.07% of SC-30, and 6.66% of SC-PVA, showing a superior rate capability of a supercapacitor. These results indicate that CP films can be served as promising separators for supercapacitors.

2.
Front Pharmacol ; 11: 1034, 2020.
Article in English | MEDLINE | ID: mdl-32792941

ABSTRACT

Atherosclerosis (AS) is an excessive chronic inflammatory hyperplasia caused by the damage of vascular endothelial cell morphology and function. Changes in mitochondrial internal conformation and increase of reactive oxygen species (ROS) can lead to energy metabolism disorders in mitochondria, which further affects the occurrence of atherosclerosis by impairing vascular endothelial function. Coenzyme Q10 (CoQ10) is one of the components of mitochondrial respiratory chain, which has the functions of electron transfer, reducing oxidative stress damage, improving mitochondrial function and promoting energy metabolism. The main purpose of this study is to investigate the protective effects of CoQ10 against AS by improving mitochondrial energy metabolism. Both in high fat diet (HFD) fed APOE -/- mice and in ox-LDL-treated HAECs, CoQ10 significantly decreased the levels of TG, TC and LDL-C and increased the levels of HDL-C, thus playing a role in regulating lipid homeostasis. Meanwhile, CoQ10 decreased the levels of LDH and MDA and increased the levels of SOD and GSH, thus playing a role in regulating oxidation level. CoQ10 also inhibited the over-release of ROS and increased ATP content to improve mitochondrial function. CoQ10 also decreased the levels of related inflammatory factors (ICAM-1, VCAM-1, IL-6, TNF-α and NLRP3). In order to study the mechanism of the experiment, AMPK and YAP were silenced in vitro. The further study suggested AMPK small interfering RNA (siRNA) and YAP small interfering RNA (siRNA) affected the expression of OPA1, a crucial protein regulating the balance of mitochondrial fusion and division and decreased the therapeutic effects of CoQ10. These results indicated that CoQ10 improved mitochondrial function, inhibited ROS production, promoted energy metabolism and attenuated AS by activating AMPK-YAP-OPA1 pathway. This study provides a possible new mechanism for CoQ10 in the treatment of AS and may bring a new hope for the prevention and treatment of AS in the future.

3.
Front Cell Dev Biol ; 8: 683, 2020.
Article in English | MEDLINE | ID: mdl-32850809

ABSTRACT

The recent outbreak of the coronavirus disease-2019 (COVID-19) caused serious challenges to the human society in China and across the world. COVID-19 induced pneumonia in human hosts and carried a highly inter-person contagiousness. The COVID-19 patients may carry severe symptoms, and some of them may even die of major organ failures. This study utilized the machine learning algorithms to build the COVID-19 severeness detection model. Support vector machine (SVM) demonstrated a promising detection accuracy after 32 features were detected to be significantly associated with the COVID-19 severeness. These 32 features were further screened for inter-feature redundancies. The final SVM model was trained using 28 features and achieved the overall accuracy 0.8148. This work may facilitate the risk estimation of whether the COVID-19 patients would develop the severe symptoms. The 28 COVID-19 severeness associated biomarkers may also be investigated for their underlining mechanisms how they were involved in the COVID-19 infections.

4.
Phys Rev Lett ; 124(21): 213603, 2020 May 29.
Article in English | MEDLINE | ID: mdl-32530692

ABSTRACT

Field-orthogonal temporal mode analysis of optical fields has recently been developed for a new framework of quantum information science. However, so far, the exact profiles of the temporal modes are not known, which makes it difficult to achieve mode selection and demultiplexing. Here, we report a novel method that measures directly the exact form of the temporal modes. This, in turn, enables us to make mode-orthogonal homodyne detection with mode-matched local oscillators. We apply the method to a pulse-pumped, specially engineered fiber parametric amplifier and demonstrate temporally multiplexed multidimensional quantum entanglement of continuous variables in telecom wavelength. The temporal mode characterization technique can be generalized to other pulse-excited systems to find their eigenmodes for multiplexing in the temporal domain.

5.
Sci Rep ; 10(1): 6278, 2020 Apr 14.
Article in English | MEDLINE | ID: mdl-32286425

ABSTRACT

Synthetic Mg2TiO4 qandilite was investigated to 50 and 40.4 GPa at room temperature using Raman spectroscopy and X-ray diffraction, respectively. The Raman measurements showed that cubic Mg2TiO4 spinel transforms to a high pressure tetragonal (I41/amd, No.141) phase at 14.7 GPa. Owing to sluggish kinetics at room temperature, the spinel phase coexists with the tetragonal phase between 14.7 and 24.3 GPa. In the X-ray diffraction experiment, transformation of the cubic Mg2TiO4 to the tetragonal structure was complete by 29.2 GPa, ~5 GPa higher than the transition pressure obtained by Raman measurements, owing to slow kinetics. The obtained isothermal bulk modulus of Mg2TiO4 spinel is KT0 = 148(3) GPa when KT0' = 6.6, or KT0 = 166(1) GPa when KT0' is fixed at 4. The isothermal bulk modulus of the high-pressure tetragonal phase is calculated to be 209(2) GPa and V0 = 270(2) Å3 when KT0' is fixed at 4, and the volume reduction on change from cubic to tetragonal phase is about 9%. The calculated thermal Grüneisen parameters (γth) of cubic and tetragonal Mg2TiO4 phases are 1.01 and 0.63. Based on the radii ratio of spinel cations, a simple model is proposed to predict post-spinel structures.

7.
Pharmacol Res ; 148: 104414, 2019 10.
Article in English | MEDLINE | ID: mdl-31449974

ABSTRACT

Atherosclerosis (AS) is one of the major causes leading to mortality of dysfunctional cardiovascular events in the menopausal women, which has long-term deficiency of estrogen. At present, the primary treatment for postmenopausal AS is hormone replacement therapy (HRT). However, it can increase the risks of ovarian and uterine cancers with long-term therapy. So seeking for a phytoestrogen which can overcome the disadvantages of HRT is a great mission. Dioscin, a traditional Chinese medicine, extracted from the roots of dioscorea nipponica, has anti-inflammatory, anti-tumor and anti-apoptosis activities. Especially, it also has estrogenic activity. Thus, this study aims to investigate the effects of dioscin on postmenopausal AS. Currently, ovariectomy (OVX) is the accepted model for AS associated with estrogen deficiency, and it can mimic the cessation of ovarian function that occurs in postmenopausal women as well. We used the high fat diet and ovariectomy(HFD-OVX)model to induce postmenopausal AS in the low-density lipoprotein receptor- deficient (LDLR-/-) mice. (1) The levels of TG, TC, LDL-C, HDLC, MDA, GSH, MDA and GSH in serum of HFD-OVX induced LDLR-/- mice were measured by colorimetric assay. (2) The artery injury of HFD-OVX induced LDLR-/- mice was detected with Oil Red O staining. (3) The protein expressions of NOX4, P22phox, IκB, p-p65, n-p65, ICAM-1, VCAM-1, caspase-3, caspase-9, bcl-2, PGC-1α, ERα, ERß in the arterial tissue of HFD-OVX induced LDLR-/- mice were detected by Western blot analysis. In vitro, the model of human aortic endothelial cells (HAECs) induced by oxidized low-density lipoprotein (ox-LDL) (150 µg /ml) was established, and the molecular mechanism of dioscin on atherosclerosis in postmenopausal women was investigated. (1) The levels of MDA, GSH, MDA and GSH in ox-LDL induced HAECs were measured by colorimetric assay. (2) Reactive Oxygen Species (ROS) of ox-LDL induced HAEC cells was detected by fluorescence staining. (3) The protein expressions of PGC-1α, ERα, ERß, NOX4, P22phox, IκB, p-p65, n-p65, ICAM-1, VCAM-1, caspase-3, caspase-9, bcl-2 and LC3 in ox-LDL induced HAECs were detected by Western blot analysis. (4) The autophagy level of ox-LDL induced HAECs was measured by transmission electron microscopy. (5) The applications of si-RNA transfection were used to explore whether dioscin could activate PGC-1α/ERα pathway to inhibit postmenopausal atherosclerosis. In vivo, we found that dioscin decreased the level of TG, TC, LDL-C and increased the level of HDLC in serum of HFD-OVX induced LDLR-/- mice, and it has protective effects to maintain the lipid homeostasis; The Oil Red O staining study showed that dioscin could significantly inhibit the formation of atherosclerotic plaques in HFD-OVX-treated LDLR-/- mice; Dioscin decreased the levels of NOX4, P22phox, p-p65, n-p65, ICAM-1, VCAM-1, caspase-3, caspase-9, but increased the levels of HDL-C, GSH, SOD, PGC-1α, ERα, ERß, IκB, Bcl-2 and elevated the autophagy level in arterial tissues of HFD-OVX induced LDLR-/- mice. It is particularly worth mentioning that the up-regulating effect of dioscin on ERα is stronger than ERß in OVX treated mice. In vitro, the results of colorimetric assay showed that dioscin decreased the level of MDA and LDH, increased the level of SOD and GSH in ox-LDL-induced HAEC cells; Dioscin also suppressed the release of ROS in ox-LDL-induced HAECs by fluorescence staining; Dioscin decreased the levels of NOX4, P22phox, p-p65, n-p65, ICAM-1, VCAM-1, caspase-3, caspase-9, but increased the levels of PGC-1α, ERα, ERß, IκB, Bcl-2 and the ratio of LC3-II/LC3-I in ox-LDL-induced HAECs; Dioscin significantly elevated the autophagy level of ox-LDL-induced HAECs by transmission electron microscopy analysis; In addition, by si-RNA transfection, we found that the inhibitory effects of dioscin on oxidative stress, inflammatory response and apoptosis might partly through PGC-1α/ERα pathway in ox-LDL induced HAECs. The data of dual-Luciferase reporter assay revealed that dioscin activated ERα at least partly through PGC-1α pathway. Dioscin significantly inhibited oxidative stress, inflammatory response, apoptosis and increased the level of autophagy in vivo and vitro. In addition, dioscin could regulate the balance of lipid metabolism. Moreover, we proved that the effects of dioscin attenuating postmenopausal atherosclerosis by inhibiting oxidative stress, inflammation and apoptosis were partly dependent on PGC-1α/ERα pathway. Therefore, dioscin, as a phytoestrogen, might become a drug for the treatment of atherosclerosis in postmenopausal women.


Subject(s)
Apoptosis/drug effects , Atherosclerosis/prevention & control , Autophagy/drug effects , Diosgenin/analogs & derivatives , Inflammation/drug therapy , Oxidative Stress/drug effects , Signal Transduction/drug effects , Animals , Atherosclerosis/metabolism , Cells, Cultured , Diosgenin/pharmacology , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Estrogen Receptor alpha/metabolism , Female , Humans , Inflammation/metabolism , Medicine, Chinese Traditional/methods , Mice , Mice, Inbred C57BL , Ovariectomy/methods , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/metabolism , Plant Extracts/pharmacology , Postmenopause/drug effects , Postmenopause/metabolism , Receptors, LDL/metabolism
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