This study investigates the effects of platinum/carbon (Pt/C) catalysts on the performance of a vanadium redox flow battery. The Pt/C catalysts were synthesized using the impregnation-reduction method. The activity of these catalysts on the V(IV)/V(V) redox reaction was investigated using cyclic voltammetry, linear sweep voltammetry, and the rotating disk electrode (RDE) technique. The reaction rate constant K0 and exchange current density i0 were calculated from the RDE data. The Ko increased from 3.37 × 10−6 cm·s−1 to 6.86 × 10−6 cm·s−1, and i0 increased from 13.79 μA to 72.96 μA as the Pt loading increased. Single-cell charge-discharge tests were performed with Pt/C on carbon felt as the positive electrode and raw carbon felt as the negative electrode. The energy efficiency of cells increased from 51.8% to 72.3% as the electrode material changed from carbon felt to Pt/C on carbon felt at a constant current density of 10 mA·cm−2. The best Cell-D energy efficiency was 20.5% higher than that without an electrocatalyst (Cell-A). The Pt/C catalyst can also effectively reduce the cell internal resistance. The charge/discharge efficiency of a single cell with different anode catalyst is increased in the following order: Pt/C 15 wt% > Pt/C 10 wt% > Pt/C 5 wt% >carbon felt

Aims/Introduction: Admission hyperglycemia is associated with poor outcome in patients with myocardial infarction. The present study evaluated the relationship between admission glucose level and other clinical variables in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). Materials and Methods: The 959 consecutive STEMI patients undergoing primary PCI were divided into five groups based on admission glucose levels of <100, 100-139, 140-189, 190-249 and ≥250 mg/dL. Their short-and long-term outcomes were compared. Results: Higher admission glucose levels were associated with significantly higher inhospital morbidity and mortality, the overall mortality rate at follow up, and the incidence of reinfarction or heart failure requiring admission or leading to mortality at follow up. The odds ratios (95% confidence interval) for in-hospital morbidity, in-hospital mortality, mortality at follow up and re-infarction or heart failure or mortality at follow up of patients with admission glucose levels ≥190 mg/dL, compared with those with admission glucose levels <190 mg/dL, were 2.12 (1.3-3.4, P = 0.001), 2.74 (1.4-5.5, P = 0.004), 2.52 (1.2-5.1, P = 0.01) and 1.70 (1.03-2.8, P = 0.04), respectively. Previously non-diabetic patients with admission glucose levels ≥250 mg/dL had significantly higher in-hospital morbidity or mortality (44 vs 70%, P = 0.03). Known diabetic patients had higher rates of reinfarction, heart failure or mortality at follow up in the 100-139 mg/dL (8 vs 27%, P = 0.04) and 140-189 mg/dL (11 vs 26%, P = 0.02) groups. Conclusions: Admission hyperglycemia, especially at glucose levels ≥190 mg/dL, is a predictor of poor prognosis in STEMI patients undergoing primary PCI.

Reprogrammed glucose metabolism and increased glycolysis have been implicated in tumor chemoresistance. The aim was to investigate the distinct roles of the glucose metabolites pyruvate and ATP in chemoresistance mechanisms, including cell death and proliferation. Our data showed higher glucose transporters in colorectal cancer (CRC) from non-responsive patients than those responsive to chemotherapy. Human CRC cell lines exposed to 5-fluorouracil (5-FU) displayed elevated cell viability and larger tumors in xenograft mouse models if cultured in high-glucose medium. Glucose conferred resistance to 5-FU-induced necroptosis via pyruvate scavenging of mitochondrial free radicals, whereas ATP replenishment had no effect on cell death. Glucose attenuated the 5-FU-induced G0/G1 shift but not the S phase arrest. Opposing effects were observed by glucose metabolites; ATP increased while pyruvate decreased the G0/G1 shift. Lastly, 5-FU-induced tumor spheroid destruction was prevented by glucose and pyruvate, but not by ATP. Our finding argues against ATP as the main effector for glucose-mediated chemoresistance and supports a key role of glycolytic pyruvate as an antioxidant for dual modes of action: necroptosis reduction and a cell cycle shift to a quiescent state.

Mesenteric ischaemia/reperfusion induces epithelial death in both forms of apoptosis and necrosis, leading to villus denudation and gut barrier damage. It remains unclear whether programmed cell necrosis [i.e. receptor-interacting protein kinase (RIP)-dependent necroptosis] is involved in ischaemic injury. Previous studies have demonstrated that enteral glucose uptake by sodium-glucose transporter 1 ameliorated ischaemia/reperfusion-induced epithelial injury, partly via anti-apoptotic signalling and maintenance of crypt proliferation. Glucose metabolism is generally assumed to be cytoprotective; however, the roles played by glucose metabolites (e.g. pyruvate and ATP) on epithelial cell death and crypt dysfunction remain elusive. The present study aimed to investigate the cytoprotective effects exerted by distinct glycolytic metabolites in ischaemic gut. Wistar rats subjected to mesenteric ischaemia were enterally instilled glucose, pyruvate or liposomal ATP. The results showed that intestinal ischaemia caused RIP1-dependent epithelial necroptosis and villus destruction accompanied by a reduction in crypt proliferation. Enteral glucose uptake decreased epithelial cell death and increased crypt proliferation, and ameliorated mucosal histological damage. Instillation of cell-permeable pyruvate suppressed epithelial cell death in an ATP-independent manner and improved the villus morphology but failed to maintain crypt function. Conversely, the administration of liposomal ATP partly restored crypt proliferation but did not reduce epithelial necroptosis and histopathological injury. Lastly, glucose and pyruvate attenuated mucosal-to-serosal macromolecular flux and prevented enteric bacterial translocation upon blood reperfusion. In conclusion, glucose metabolites protect against ischaemic injury through distinct modes and sites, including inhibition of epithelial necroptosis by pyruvate and the promotion of crypt proliferation by ATP.

This investigation focuses on the effect of titanium dioxide (TiO 2 ) coatings of a carbon black (XC-72) negative electrode on the performance of a vanadium redox flow battery (VRFB). TiO 2 , a hydrophilic material, was added to the carbon electrode to improve the wettability and reduce the electrical resistance of the electrode surface. The electrochemical performances of homemade TiO 2 , commercial TiO 2 , and carbon felt are investigated by using cyclic voltammetry and single-cell charge-discharge measurements. An electrode with 20 wt% of fabricated TiO 2 loading at a scan rate of 0.006 V s −1 shows a specific capacitance (C s,t ) of 186.2 F g −1 , which is 55.5% and 12.2% higher than that of pure carbon electrode (119.7 F g −1 ) and commercial TiO 2 (166.0 F g −1 ), respectively. At current density of 200 mA cm −2 , the energy storage efficiency (η E = 65.4%) of the single cell with 20 wt% homemade TiO 2 /C-containing carbon felt negative electrode is 16.0% and 6.1% higher than that of the negative electrode with raw carbon felt (η E = 56.4%) and of the negative electrode containing commercial TiO 2 /C (η E = 61.6%), respectively. These results demonstrate the potential application of TiO 2 /C electrodes for high-efficiency VRFBs at high current densities. Vanadium redox flow battery (VRFB) has been proposed as a promising candidate for large scale energy storage applications, such as load-leveling applications. VRFB can store and stabilize intermittent electricity generated from wind turbine or photovoltaic. VRBF has several advantages over other types of batteries, such as excellent electrochemical reversibility, high roundtrip efficiency, flexible, and negligible cross-contamination between positive and negative electrolytes.1-5 VRFB employs V(IV)/V(V) and V(II)/V(III) redox couples as positive and negative half-cells, respectively, with the standard open circuit cell potential approximate 1.26 V at 100% state of charge. 6Carbon felt is a typical electrode material and it has wide operating electrode potential range, chemically stable, high surface area, and reasonable price. However, carbon felt electrode shows poor electrochemical activity. Therefore, much attention has been focus to electrode modification to enhance its electrochemical properties. [7][8][9][10][11][12][13][14] Several alternative electrode materials have been proposed to improve electrode performance, such as metal electrodeposition on carbon fibers. Various metal compounds have also been deposited on graphite fibers to improve the catalytic activity for vanadium redox couples and to enhance electrode stability in acidic vanadium solution. In the literature, metal compounds deposited on carbon felts include IrO 2, 9 Ru(O 2 ), 10 and Ir, 11 whereas others include partial modification of the functional groups on the graphite surface.12,13 The coating of metal nanoparticles on the fiber of carbon felt is a promising approach. Recently, transition metal oxides, e.g. TiO 2 , ZnO, have been studied extensively as a water adsorbent for improv...