Intermetallic Pd3Pb nanocrystals with controlled size and cubic geometry exposing (100) facets are synthesized and tested as electrocatalysts for ethanol oxidation in alkaline media. We observe the ...ethanol oxidation activity and stability to be size-dependent. The 10 nm Pd3Pb nanocrystals display the highest initial current densities, but after few hundred cycles, the current density of smaller nanocrystals becomes much larger. All of the catalysts exhibit a pronounced current decay during the first 500 s of continuous operation, which is associated with the accumulation of strongly adsorbed reaction intermediates, blocking reaction sites. These adsorbed species can be removed by cycling the catalysts or maintaining them at slightly higher potentials for a short period of time to oxidize and later reduce the Pd surface. Such simple cleaning processes, that can be performed during operation breaks without cell disassembly, is sufficient to effectively remove the poisoning species adsorbed on the surface and recover the electrocatalytic activity.
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IJS, KILJ, NUK, PNG, UL, UM
Exosomes mediate cellular communications in cancer by transmitting active molecules. However, the CAFs-derived molecular determinants that regulate esophageal squamous cell carcinoma (ESCC) ...metastasis have not been fully characterized. The purpose of this study was to investigate the potential roles of exosomal LINC01410 of ESCC cells. The characteristics of exosomes were identified using transmission electron microscope (TEM), Nanoparticle Tracking Analysis (NTA). The expression of LINC01410 and miR-122–5p was analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) assay. The biological roles of LINC01410 in ESCC cells were investigated using transwell assay. Western blot assay was employed to detect protein levels. The potential downstream molecular mechanism of LINC01410 was demonstrated with dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay and RNA pull down. CAFs promote the metastasis and epithelial-mesenchymal transition (EMT) of ESCC cells. CAFs exert their roles by transferring exosomes to ESCC cells, leading to a significant increase of LINC01410 level in ESCC cells. Mechanically, LINC01410 secreted by CAFs-Exo could contribute to metastasis and EMT by sponging miR-122–5p and increasing PKM2 level in TE-1 and Eca-109 cells. Additionally, LINC01410/miR-122–5p/PKM2 axis affecting ESCC metastasis and EMT in vitro and in vivo.
•CAFs promote metastasis and EMT of ESCC cells.•CAF-derived exosomes promote metastasis and EMT of ESCC.•Exosomal deliver LINC01410 essentially for metastasis and EMT of ESCC.•LINC01410/miR-122–5p/PKM2 axis regulates ESCC metastasis and EMT.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ
Background Myoglobin and cardiac troponin T are often elevated in patients with ischemic stroke. However, the association, if any, between both myoglobin and troponin T levels and hematoma volume in ...patients with intracerebral hemorrhage remains to be established. We investigate the possible relationship between admission myoglobin and troponin T levels and hematoma volume and growth. Methods A total of 143 patients with intracerebral hemorrhage admitted within 72 hours after symptom onset were divided into 4 groups according to the quartile of myoglobin levels. The information of hematoma was assessed with computed tomography scans. Serum myoglobin and cardiac troponin were tested at admission. The relationship between myoglobin levels and hematoma volume and growth was performed using univariate and multiple logistic regression and linear regression. Results High levels of serum myoglobin were associated with larger hematoma volume. In the highest quartile compared with the lowest quartile of myoglobin, the crude and adjusted odds ratios for the incidence of baseline hematoma volume greater than 30 mL were 2.14 (95% confidence interval 1.45-3.15) and 2.78 (95% confidence interval 1.57-5.00), respectively, in logistic regression. In linear regression, the adjusted B for the relationship of myoglobin and hematoma volume and the change of hematoma volume was .02 (95% confidence interval .01-.04, P = .007) and .021 (95% confidence interval .01-.03, P < .001), respectively, whereas high level of troponin T was not associated with large hematoma volume. Conclusion Our results first demonstrate that myoglobin is associated with larger hematoma volume and growth after adjusting potential confounding factors.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
High-brightness light-emitting diode (LED) is next generation of green lighting. However, the bulky electrolytic capacitor is required to compensate the difference of pulsating power, thereby ...restricting the lifetime. Meanwhile, the existing drivers based on pulse frequency modulation (PFM) is bound to arouse heavy electromagnetic interference. In this paper, the series resonant converter based LED drive is proposed to overcome the shortcomings of electrolytic capacitor and PFM control. The proposed method is to attenuate the low frequency ripples delivered from the power factor correction (PFC) to LEDs; therefore, the capacitance is reduced for energy storage of offline LED drivers. On account of the adoption of the switching controlled capacitor (SCC), the constant frequency control is achieved by the regulations of the equivalent capacitance. Half-bridge switches are shared by the bridgeless PFC and the resonant unit, therefore, single-stage LED drive is realized with high efficiency. In addition, SCC is simultaneously shared for the upper and lower half-bridge to reduce the cost and improve the power density. Operating principle, design considerations, and performance comparisons are examined in detail. Finally, all the superior performances of proposed LED driver are verified by simulation and experimental prototypes with two-channel LEDs, and rated output power of 80 W.
Developing high-strength welded joint of heavy-thick titanium alloy plates is in immediate need to unravel the strength-enhanced behaviors for high-pressure and low-temperature performance of ...deep-sea submersibles. Here, we synergistically employed transmission electron microscope (TEM) and electron back-scattered diffraction (EBSD) technologies to micro-crystallographically unravel the evolution behaviors of weld microstructure, grain orientation and grain boundaries for the welded joint of the heavy-thick Ti-6Al-4V plates with the thickness of up to 60 mm. Resulted, the strength-enhanced welded joint was evidently ascribed to the transformation of lath martensite into basketweave-martensite and the rigid-flexible mixture strategy of the enhanced conical-texture and the weakened basal-texture and cylindrical-texture. Furthermore, the remarkably lowered geometrically necessary dislocations (GNDs) density and the greatly decreased deformation-prone grains number due to the transformation of low-into-high angle grain boundaries indispensably strengthened the joint strength. Therefore, this work has made clear the strength-enhanced behaviors of Ti-6Al-4V welded joints for substantially improving high-strength welded structure of heavy-thick titanium alloy plates, and sufficiently promoting the service safety for deep-sea submersibles.
•Transformation of lath martensite into basketweave-martensite enhanced the welded joint strength.•Thermal cycling caused the rigid-flexible mixture of the enhanced conical-texture and the weakened basal-texture.•Transformation of low-into-high angle grain boundaries lowered GNDs density and decreased deformation-prone grains number.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ
With complex process integration approach and severe fabrication limitations caused by introduction of new materials and diminishing process margins, there are mounting concerns with the increased ...failure rate at the early life cycle (e.g.<1year operation) of product application known as infant mortality failures. A paradigm change in reliability qualification methodology aim at understanding the impact of variation on reliability is required to ensure reliability robustness. Using Electromigration (EM) as an example, this paper described a methodology where the impact of process variation on reliability is studied. A model that predicts the impact of process variation on EM sigma is also proposed which enables variation and its impact on reliability to be quantified. Using this methodology, the critical process parameters impacting reliability could be identified and controlled to ensure reliability robustness.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Metallenes are an emerging class of two-dimensional (2D) material with outstanding potential in electrocatalysis. Herein, we present a new PdMoSb trimetallene produced by a facile wet-chemistry ...procedure and tested for the alcohol oxidation reaction. PdMoSb shows an extremely high Pd utilization and superior performance toward ethanol, methanol, and glycerol electro-oxidation compared with PdMo and commercial Pd/C catalysts. Experimental results and density functional theory calculations reveal that the enhanced activity relies not only on the high surface area that characterizes the ultrathin 2D metallene structure, but also on the particular electronic configuration of Sb. Sb facilitates OH
−
adsorption in the reactive-intermediate pathway and strongly enhances the CO tolerance in the poisoning-intermediate pathway for alcohol oxidation. The excellent alcohol oxidation performance of PdMoSb trimetallene demonstrates the high potential of multimetallenes in the field of electrocatalysis.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Coronary artery damage from Kawasaki disease (KD) is closely linked to the dysfunction of the endothelial progenitor cells (EPCs). The aim of the present study was to evaluate the modulatory effect ...of granulocyte colony-stimulating factor (G-CSF) on EPCs and elastin breakdown of coronary arteries in a KD mouse model.
A Lactobacillus casei cell wall extract (LCWE)-induced KD model was established in C57BL/6 mice that were subsequently administrated with recombinant human G-CSF (rhG-CSF). Nω-nitro-L-arginine methyl ester (L-NAME) was administrated for the negative intervention. Evaluations included coronary artery lesions, EPC number and functions, and the plasma concentration of nitric oxide (NO).
Elastin breakdown was found in the coronary arteries of model mice 56 days after injection of LCWE. The number of circulating EPCs, plasma concentration of NO, and functions of bone marrow EPCs, including proliferation, adhesion, and migration abilities, were all lower in the KD model group compared with those in the control group. After administration of rhG-CSF, the number of circulating EPCs and plasma concentration of NO were increased significantly compared with those in the KD model group. There were also increases in the functional indexes of EPCs. Furthermore, rhG-CSF administration improved the elastin breakdown effectively. However, these protective effects of rhG-CSF on coronary arteries were attenuated by L-NAME.
The present study indicated that the administration of G-CSF prevents elastin breakdown of the coronary arteries by enhancing the number and functions of EPCs via the NO system, and then accelerates the repair of coronary artery lesions in the KD.
Chinese Modular High-Temperature Gas-Cooled Reactor HTR-PM is a promising energy source for comprehensive utilization. The original coordinated control strategy of HTR-PM is a “turbine following ...reactor” strategy, which is not able to perform load following operation. To have more flexible operation capability, this paper presents a load following control strategy for HTR-PM. A balance of plant (BOP) model of HTR-PM is first developed for dynamic simulation, including the once through steam generator (OTSG), turbine generator, condenser, feed water heater, deaerator, feed water pump, valves and piping system. Then the original coordinated control strategy and the proposed load following control strategy are clarified, and model validation, simulation results are documented respectively. For turbine trip without reactor shutdown from 100%PFP transient, the steam dump strategy is improved to meet the safety requirements. Results demonstrate that the proposed load following strategy can meet the requirements of safety operation, which is desirable for participation in peak load regulating of power system.
•A load following control strategy for Chinese Modular High-Temperature Gas-Cooled Reactor HTR-PM is proposed.•HTR-PM balance of plant system is modeled and validated.•The proposed control strategy is verified by simulations of typical operation transients.•Steam dump system is improved to enhance system performance.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ
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