39 research outputs found

    Circulating BMP9 Protects the Pulmonary Endothelium during Inflammation-induced Lung Injury in Mice.

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    Rationale: Pulmonary endothelial permeability contributes to the high-permeability pulmonary edema that characterizes acute respiratory distress syndrome. Circulating BMP9 (bone morphogenetic protein 9) is emerging as an important regulator of pulmonary vascular homeostasis. Objectives:To determine whether endogenous BMP9 plays a role in preserving pulmonary endothelial integrity and whether loss of endogenous BMP9 occurs during LPS challenge. Methods: A BMP9-neutralizing antibody was administrated to healthy adult mice, and lung vasculature was examined. Potential mechanisms were delineated by transcript analysis in human lung endothelial cells. The impact of BMP9 administration was evaluated in a murine acute lung injury model induced by inhaled LPS. Levels of BMP9 were measured in plasma from patients with sepsis and from endotoxemic mice. Measurements and Main Results: Subacute neutralization of endogenous BMP9 in mice (N = 12) resulted in increased lung vascular permeability (P = 0.022), interstitial edema (P = 0.0047), and neutrophil extravasation (P = 0.029) compared with IgG control treatment (N = 6). In pulmonary endothelial cells, BMP9 regulated transcriptome pathways implicated in vascular permeability and cell-membrane integrity. Augmentation of BMP9 signaling in mice (N = 8) prevented inhaled LPS-induced lung injury (P = 0.0027) and edema (P < 0.0001). In endotoxemic mice (N = 12), endogenous circulating BMP9 concentrations were markedly reduced, the causes of which include a transient reduction in hepatic BMP9 mRNA expression and increased elastase activity in plasma. In human patients with sepsis (N = 10), circulating concentratons of BMP9 were also markedly reduced (P < 0.0001). Conclusions: Endogenous circulating BMP9 is a pulmonary endothelial-protective factor, downregulated during inflammation. Exogenous BMP9 offers a potential therapy to prevent increased pulmonary endothelial permeability in lung injury

    PREPARATION AND APPLICATIONS OF STIMULI-RESPONSIVE COMPOSITE MATERIALS

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    A New Boiler-turbine-heating Coordinated Control Strategy to Improve the Operating Flexibility of CHP Units

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    The operating flexibility of the power units is getting increasing attention from power systems especially those with large-scale fluctuating renewable energies. However, the combined heat and power (CHP) units are getting a bottleneck because their electricity productions are restricted by heat productions. This study aims to develop an electric-heat coordinated control strategy to make the CHP units more flexible. First of all, the dynamic model for a 300 MW CHP unit is set up, and its linear state-space description is obtained. A control strategy based on linear quadratic regulator (LQR) is then developed to satisfy different heat-power demands in various operating conditions. The control weights Q and R are optimized by particle swarm optimization. Moreover, the improved coordinated control strategy based on precise energy balance is put forward to increase the CHP power ramp rate considering electricity priority strategy and recovery control of the heat source. Finally, the simulation results show that the improved strategy is suitable for various CHP operating scenarios, and the case for electricity priority and heat recovery control significantly improves the unit power rate on the premise of stable heat supply. This work provides a reliable and flexible control mode for CHP units, which can support the power system stability and renewable energy integration.</p

    IGF-1-releasing PLGA nanoparticles modified 3D printed PCL scaffolds for cartilage tissue engineering

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    The aim of this study is to fabricate and test a 3D-printed PCL scaffold incorporating IGF-1-releasing PLGA nanoparticles for cartilage tissue engineering. IGF-1 loaded PLGA nanoparticles were produced by the double-emulsion method, and were incorporated onto 3D printed PCL scaffolds via PDA. Particle size, loading effciency (LE) and encapsulation effciency (EE) of the nanoparticles were examined. SEM, pore size, porosity, compression testing, contact angle, IGF-1 release kinetics of the composite scaffolds were also determined. For cell culture studies, CCK-8, Live/dead, MTT, GAG content and expression level of chondrocytes specific proteins and genes and HIF-1α were also tested. There was no difference of the nanoparticle size. And the LE and EE of IGF-1 in PLGA nanoparticles was about 5.53 ± 0.12% and 61.26 ± 2.71%, respectively. There was a slower, sustained release for all drug-loaded nanoparticles PLGA/PDA/PCL scaffolds. There was no difference of pore size, porosity, compressive strength of each scaffold. The contact angles PCL scaffolds were significant decreased when coated with PDA and PLGA nanoparticales. (p < .05) Live/dead staining showed more cells attached to the IGF-1 PLGA/PDA/PCL scaffolds. The CCK-8 and MTT assay showed higher cell proliferation and better biocompatibility of the IGF-1 PLGA/PDA/PCL scaffolds. (p < .05) GAG content, chondrogenic protein and gene expression level of SOX-9, COL-II, ACAN, and HIF pathway related gene (HIF-1α) were significantly higher in IGF-1 PLGA/PDA/PCL scaffolds group compared to other groups. (p < .05) IGF-1 PLGA/PDA/PCL scaffolds may be a better method for sustained IGF-1 administration and a promising scaffold for cartilage tissue engineering

    Fabrication of Ga<sub>2</sub>O<sub>3</sub> Schottky Barrier Diode and Heterojunction Diode by MOCVD

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    In this article, we reported on a Ga2O3-based Schottky barrier diode and heterojunction diode from MOCVD. The Si-doped n-type Ga2O3 drift layer, grown by MOCVD, exhibited high crystal quality, flat surfaces, and uniform doping. The distribution of unintentional impurities in the films was studied. Then nickel Schottky barrier diode and p-NiO/n-Ga2O3 heterojunction diode were fabricated and measured. Without any electric field management structure, the Schottky barrier diode and heterojunction diode have specific resistances of 3.0 mΩ·cm2 and 6.2 mΩ·cm2, breakdown voltages of 380 V and 740 V, thus yielding power figures of merit of 48 MW·cm−2 and 88 MW·cm−2, respectively. Besides, both devices exhibit a current on/off ratio of more than 1010. This shows the prospect of MOCVD in power device manufacture

    Carbon Capsules of Ionic Liquid for Enhanced Performance of Electrochemical Double-Layer Capacitors

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    Ion accessibility, large surface area, and complete wetting of a carbonaceous electrode by the electrolyte are crucial for high-performance electrochemical double-layer capacitors. Herein, we report a facile and scalable method to prepare electrode–electrolyte hybrid materials, where an ionic liquid (IL) electrolyte is encapsulated within a shell of reduced graphene oxide (rGO) nanosheets as the active electrode material (called rGO-IL capsules). These structures were templated using a Pickering emulsion consisting of a dispersed phase of 1-methyl-3-butylimidazolium hexafluorophosphate ([bmim]­[PF<sub>6</sub>]) and a continuous water phase; graphene oxide nanosheets were used as the surfactant, and interfacial polymerization yielded polyurea that bound the nanosheets together to form the capsule shell. This method prevents the aggregation and restacking of GO nanosheets and allows wetting of the materials by IL. The chemical composition, thermal properties, morphology, and electrochemical behavior of these new hybrid architectures are fully characterized. Specific capacitances of 80 F g<sup>–1</sup> at 18 °C and 127 F g<sup>–1</sup> at 60 °C were achieved at a scan rate of 10 mV s<sup>–1</sup> for symmetric coin cells of rGO-IL capsules. These architected materials have higher capacitance at low temperature (18 °C) across many scan rates (10–500 mV s<sup>–1</sup>) compared with analogous cells with the porous carbon YP-50. These results demonstrate a distinct and important methodology to enhance the performance of electrochemical double-layer capacitors by incorporating electrolyte and carbon material together during synthesis

    Carbon Capsules of Ionic Liquid for Enhanced Performance of Electrochemical Double-Layer Capacitors

    No full text
    Ion accessibility, large surface area, and complete wetting of a carbonaceous electrode by the electrolyte are crucial for high-performance electrochemical double-layer capacitors. Herein, we report a facile and scalable method to prepare electrode–electrolyte hybrid materials, where an ionic liquid (IL) electrolyte is encapsulated within a shell of reduced graphene oxide (rGO) nanosheets as the active electrode material (called rGO-IL capsules). These structures were templated using a Pickering emulsion consisting of a dispersed phase of 1-methyl-3-butylimidazolium hexafluorophosphate ([bmim]­[PF<sub>6</sub>]) and a continuous water phase; graphene oxide nanosheets were used as the surfactant, and interfacial polymerization yielded polyurea that bound the nanosheets together to form the capsule shell. This method prevents the aggregation and restacking of GO nanosheets and allows wetting of the materials by IL. The chemical composition, thermal properties, morphology, and electrochemical behavior of these new hybrid architectures are fully characterized. Specific capacitances of 80 F g<sup>–1</sup> at 18 °C and 127 F g<sup>–1</sup> at 60 °C were achieved at a scan rate of 10 mV s<sup>–1</sup> for symmetric coin cells of rGO-IL capsules. These architected materials have higher capacitance at low temperature (18 °C) across many scan rates (10–500 mV s<sup>–1</sup>) compared with analogous cells with the porous carbon YP-50. These results demonstrate a distinct and important methodology to enhance the performance of electrochemical double-layer capacitors by incorporating electrolyte and carbon material together during synthesis
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