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In the present work, a flexible carbon sponge is experimentally characterized and proposed as an alternative electrode for advanced vanadium redox flow batteries. Such an electrode is prepared via directly carbonizing the commercially-available and inexpensive melamine formaldehyde resin sponge in argon, to inherit the well-defined and three-dimensional bi-continuous architecture of the melamine sponge with 99.6% porosity and 40 μm average pore size. By applying the carbon sponges as the electrodes, it is demonstrated that the vanadium flow battery at 200 mA cm

Study ObjectivesIncreased incidence of narcolepsy was reported in children during the 2009 H1N1 pandemic following Pandemrix, a H1N1 flu vaccine. A link with A(H1N1) pdm09 infections remains controversial. Using nationwide surveillance data from China (1990 to 2017), the epidemiology of narcolepsy was analyzed.MethodsIndividual records of narcolepsy patients were collected from 15 of 42 hospitals across China known to diagnose cases. Incidence was estimated assuming the representativeness of these hospitals. Age-specific incidence, epidemiological and clinical characteristics of patients were evaluated before, during, and after the 2009 H1N1 pandemic. Sensitivity analyses were conducted by including NT1 cases only and excluding the effect of the 2009 H1N1 vaccination.ResultsAverage annual incidence was 0.79 per 100 000 person-years (PY) from 1990 to 2017 and 1.08 per 100 000 PY from 2003 to 2017. Incidence increased 4.17 (95% CI 4.12, 4.22) and 1.42 (95% CI 1.41, 1.44) fold during and after the 2009 H1N1 pandemic when compared to baseline. These results were robust in sensitivity analyses. Patients with the onset of narcolepsy during the pandemic period were younger (notably in 5–9-year-old strata), and the age shift toward younger children reversed to baseline following the pandemic.ConclusionsIncreased incidence of narcolepsy was observed during the 2009 H1N1 pandemic period. This is likely to be associated with the circulation of the wild type A(H1N1)pdm09 virus. This observation should be considered for future influenza pandemic preparedness plans.

BACKGROUND Erectile dysfunction (ED) with obstructive sleep apnoea (OSA) is a relatively common issue for men. A number of clinical studies have demonstrated that continuous positive airway pressure (CPAP) therapy may effectively alleviate ED symptoms from patients with OSA. METHODS PubMed, MEDLINE, EMBASE and Cochrane Library databases were utilised and searched for the relevant studies up to September 2, 2019. The International Index of Erectile Function 5 (IIEF-5) scoring system from the patients before and after receiving their CPAP therapy were collected according to the strict inclusion and exclusion criteria. REVMEN 5.3 software was applied for the meta-analysis. RESULTS A total of seven publications consisted of 206 ED patients with OSA were included in the study. ED patients with OSA received CPAP treatment were significantly improved based on the IIEF-5 scores [Weighted Mean Difference (WMD) = 1.14, 95% confidence interval (CI) = 0.89-1.38, z = 9.09, p < 0.0001].Our research found that the high heterogeneity is mainly due to Zhang's data, with a higher apnoea-hypopnea index (AHI) compared to the other included studies. A moderate heterogeneity (I2 = 54%, P = 0.05) was found after removal of Zhang's data. CONCLUSION The results suggest that continuous positive airway pressure therapy relive erectile dysfunction symptoms in patients with obstructive sleep apnoea. However, further evidence is needed due to the insufficient number of included patients and high heterogeneity.

Large clinical trials and real-world studies have demonstrated that the beneficial effects of sodium-glucose co-transporter 2 (SGLT2) inhibitors on renal outcomes regardless of the presence of diabetes. However, the mechanism remains obscure. Here, we analyze the anti-fibrotic and anti-inflammatory effects of dapagliflozin, a SGLT2 inhibitor, on renal alternations using the ischemia/reperfusion-induced fibrosis model. Transcriptome and metabolome analysis showed that the accumulation of tricarboxylic acid (TCA) cycle metabolites and upregulation of inflammation in fibrosis renal cortical tissue were mitigated by dapagliflozin treatment. Moreover, dapagliflozin markedly relieved the activation of mammalian target of rapamycin and hypoxia inducible factor-1α signaling and restored tubular cell-preferred fatty acid oxidation. Notably, NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome activation was strikingly blocked by dapagliflozin. We further demonstrated that the immunomodulatory metabolite itaconate derived from the TCA cycle was significantly boosted as a result of decreased isocitrate dehydrogenase 2 and increased immune-responsive gene 1 and mitochondrial citrate carrier in dapagliflozin-treated mice, which contributed to the inhibitory effect of dapagliflozin on NLRP3 inflammasome activation. Furthermore, administration of cell-permeable itaconate surrogate prevented activation of NLRP3 inflammasome and protected kidney against fibrosis development. Our results identify a novel mechanism coupling metabolism and inflammation for kidney benefits of SGLT2 inhibition in progressive chronic kidney disease.

Electrode architecture design is vitally important for achieving high-power and long-life vanadium redox flow batteries. This work starts with a rationale for the polarization losses of current flow battery electrodes on a basis of the well-developed design of a proton exchange membrane fuel cell. With a gained understanding from the electrode design of a fuel cell, an attempt is made to engineer the architecture of carbon felt by creating a nano-catalytic layer on carbon fiber surfaces via a facile and powerful copper oxide etching method. By engraving nano-holes on fiber surfaces, the carbon felt can deliver attributes of expanded reaction surface area, abundant defective sites and excellent structural stability under swift-flowing electrolyte without sacrificing mass transport properties. With the nano-holed and defective carbon felt, the battery demonstrates a remarkably improved performance with 85.1% energy efficiency at 320 mA cm−2, 21.8% larger than that of the pristine carbon felt. In addition, the flow battery with this new electrode shows excellent long-term stability up to 2000 cycles. It is envisioned that such an electrode design strategy would inspire the future development of advanced fibrous electrodes for flow cell applications.

Inhibition of sodium–glucose cotransporter 2 (SGLT2) in the proximal tubule of the kidney has emerged as an effective antihyperglycemic treatment. The potential protective role of SGLT2 inhibition on diabetic kidney disease (DKD) and underlying mechanism, however, remains unknown. In this study, metabolic switch was examined using kidney samples from human with diabetes and streptozocin (STZ)-induced experimental mouse model of diabetes treated with or without SGLT2 inhibitor dapagliflozin. Results were further validated using primarily cultured proximal tubule epithelial cells. We found that DKD development and progression to renal fibrosis entailed profound changes in proximal tubule metabolism, characterized by a switch from fatty acid utilization to glycolysis and lipid accumulation, which is associated with the increased expression of HIF-1α. Diabetes-induced tubulointerstitial damage, such as macrophage infiltration and fibrosis, was significantly improved by dapagliflozin. Consistent with the effects of these beneficial interventions, the metabolic disorder was almost completely eliminated by dapagliflozin. The increased level of HIF-1α in renal proximal tubule was nearly nullified by dapagliflozin. Moreover, dapagliflozin protects against glucose-induced metabolic shift in PTCs via inhibiting HIF-1α. It suggests that SGLT2 inhibition is efficient in rectifying the metabolic disorder and may be a novel prevention and treatment strategy for kidney tubule in DKD.

The thin-film electrode has been regarded as one of the desirable options for the vanadium redox flow battery. However, most of the thin-film electrodes developed to date suffer from high mass transport resistance and deliver unsatisfactory performance. In this work, we proposed a dual-layer thin-film electrode, consisting of a backing layer and a catalyst layer, for flow batteries. The backing layer with larger pores is adapted to improve the concentration distribution as well as to provide mechanical support while the catalyst layer with smaller pores provides sufficient active sites. The electrospun fiber mat is adopted as catalyst layer and backing layers in the study include carbon paper, carbon cloth and graphite felt. It is showed that carbon cloth supported electrospun fiber mat electrode demonstrates an energy efficiency of 76.1% at the current density of 240 mA cm−2, which is much higher that achieved by conventional electrospun fiber mat electrodes (61.9%). After optimizations of flow field designs and key operational parameters, the energy efficiency of battery with dual-layer structured electrodes can reach as high as 80.2% at a current density of 240 mA cm−2. In addition, the present battery can stably operate for more than 800 cycles without obvious decay.

In this work, we propose to bind carbon nanofibrous networks onto a carbon felt substrate via the self-assembly process of polyaniline for vanadium redox flow batteries. The binder-free carbon nano-network wrapped carbon felt has a specific surface area of 161 m2 g−1, which is one hundred times higher than that of pristine carbon felt (0.4 m2 g−1) and thermally treated carbon felt (1.0 m2 g−1). Besides, the surface compositions of carbon nanofibers are also optimized by sulfur and nitrogen co-doping to selectively catalyze vanadium redox reactions with low parasitic reaction activity. It was found that the optimized N–S co-doping and the hierarchically porous structure collaboratively provide abundant active sites and an efficient mass transfer pathway, promoting the advection–diffusion–reaction process. Meanwhile, the nanofiber network also improves the interconnectivity among the micron-scale fibers of carbon felt, reducing the cell internal resistance. As a result, the present electrode exhibits an encouraging energy efficiency of 82.4% at a remarkably high current density of 320 mA cm−2 in a vanadium redox flow battery system, as compared to that obtained by the thermally treated carbon felt (66.8%). Furthermore, the carbon nano-network wrapped carbon felt also demonstrates a superior long-term stability over 1000 cycles, showing great promise in practical flow battery applications.

Hybrid flow batteries are one of the most promising technologies for storing the electricity generated from intermittent renewables, such as wind and solar. However, most of the existing hybrid systems currently suffer from low power density and poor cycle performance resulted from the parasitic reactions. To mitigate these issues, here we report a tin-iron hybrid flow battery in which the stannous chloride anolyte is separated from the ferric/ferrous chloride catholyte. With the reversible tin metal deposition/stripping and ferric/ferrous chloride redox reactions at carbon surfaces, the present battery delivers an energy efficiency of 78.5% even at the current density of 200 mA cm−2. In addition, owing to high hydrogen overvoltage of metallic tin, the parasitic hydrogen evolution reaction in the negative electrode can be largely avoided so that the battery can stably operate over 700 cycles without obvious efficiency decay. With the excellent rate and cycle performance, it is envisioned that the tin-iron flow battery is a promising candidate for large-scale energy storage applications.

Simultaneously achieving fast mass transfer and high electrochemical activity has been a central issue of the porous electrode design of vanadium redox flow batteries (VRFBs). In this work, we present a bio-inspired multiscale-pore-network structured carbon felt electrode via chemistry of metal extraction for VRFBs. For the uniquely developed electrode, the micron-scale pores formed by the intersected carbon fibers are favorable for electrolyte permeation while the vanadium ion diffusion and redox reactions are promoted by the submicron-scale and nanoscale pores on the carbon fiber surfaces. Besides, oxygen and nitrogen functional groups are also introduced onto electrode surfaces to synergistically improve the catalytic activity and wettability. The superb structural and surface characteristics of the present multiscale electrode result in an encouraging VRFB performance with an energy efficiency of 81.9% at a current density of as high as 320 mA cm−2, which is 15.2% higher than that of pristine (single-scale) carbon felt electrodes. Furthermore, the battery with the multiscale electrodes can stably operate for 500 cycles without an obvious efficiency decay, verifying the excellent stability of such a structure. In principle, the multiscale electrode design can also be extended to other types of flow-cell architectured electrochemical systems that involve multiscale processes.

Objective: To evaluate systematically the effects of continuous positive airway pressure (CPAP) on blood pressure in patients with resistant hypertension and obstructive sleep apnea (OSA). Methods: The Cochrane Library, PubMed, ScienceDirect, and the Web of Science were searched for studies investigating the effects of CPAP on blood pressure in patients with resistant hypertension and OSA. The selected studies underwent quality assessment and meta-analysis, as well as being tested for heterogeneity. Results: Six randomized controlled trials were included in the meta-analysis. The pooled estimates of the changes in mean systolic blood pressure and mean diastolic blood pressure (as assessed by 24-h ambulatory blood pressure monitoring) were −5.40 mmHg (95% CI: −9.17 to −1.64; p = 0.001; I2 = 74%) and −3.86 mmHg (95% CI: −6.41 to −1.30; p = 0.00001; I2 = 79%), respectively. Conclusions: CPAP therapy can significantly reduce blood pressure in patients with resistant hypertension and OSA. RESUMO Objetivo: Avaliar sistematicamente os efeitos da continuous positive airway pressure (CPAP, pressão positiva contínua nas vias aéreas) na pressão arterial em pacientes com hipertensão resistente e apneia obstrutiva do sono (AOS). Métodos: Estudos que investigassem os efeitos da CPAP na pressão arterial em pacientes com hipertensão resistente e AOS foram buscados nos seguintes bancos de dados eletrônicos: Cochrane Library; PubMed; ScienceDirect e Web of Science. Os estudos selecionados foram submetidos a avaliação de qualidade, meta-análise e teste de heterogeneidade. Resultados: Foram incluídos na meta-análise seis ensaios clínicos controlados aleatórios. As estimativas combinadas das alterações das médias de pressão arterial sistólica e pressão arterial diastólica (medidas por meio de monitoração ambulatorial da pressão arterial durante 24 h) foram de −5,40 mmHg (IC95%: −9,17 a −1,64; p = 0,001; I2 = 74%) e −3,86 mmHg (IC95%: −6,41 a −1,30; p = 0,00001; I2 = 79%), respectivamente. Conclusões: O tratamento com CPAP é capaz de reduzir significativamente a pressão arterial em pacientes com hipertensão resistente e AOS.

Component materials and flow fields are key design parameters that influence the advection-diffusion-reaction process and thereby the performance of a Sn–Fe hybrid flow battery. In this work, various electrode configurations (empty chamber and porous carbon-based electrodes), membranes (cation and anion conducting) and flow fields (serpentine and interdigitated) are systematically investigated to elucidate their effects on the unique charge/discharge behaviors of the Sn–Fe flow battery with tin metal plating/striping. It is found that the battery capacity roughly increases linearly with the porosity of the porous electrode especially at low current densities, and a highly porous electrode (graphite felt) is more desirable than an empty chamber configuration in terms of capacity and power density. In addition, as compared to cation exchange membrane (Nafion 212), the anion exchange membrane (Fumasep FAP-450) exhibits improved capacities and columbic efficiencies in sulfuric acid-based electrolytes at low current densities due to the reduction of cation crossover. Interestingly, it is showed that although a serpentine flow field and a low flow rate generally lead to poor battery performance, they tend to ameliorate the maldistribution of plated tin at the negative electrode owing to the restricted mass transfer of reactants.

Redox flow batteries (RFBs), which combines the attributes of fuel cells and solid-state batteries, have been recognized as one of leading technologies for storing electricity that generated from solar and wind farms due to the striking advantages, including excellent scalability, high efficiency, long lifetime as well as high safety [1]. Despite the attractive merits, the widespread deployment of this type of technology was significantly limited by technical and economical issues, such as low power density, high capacity decay rate, low energy density and high capital cost [2]. To address these issues, electrode and membrane designs are of great importance. For instance, electrode design over porous structure and surface properties is critically important for improving the power density and lowering the capital cost. With regard to the electrode design and selection, several types of carbon-fiber based electrodes, such as graphite/carbon felt, carbon paper and carbon cloth, have been employed as the electrodes of RFBs and associated pretreatment procedures have also been investigated, demonstrating decent performance in different RFB systems [3]. However, comprehensive comparison studies on these porous electrodes in RFBs are scarce. In this presentation, we will offer a comprehensive comparison between the state of art RFB electrodes (carbon felt, carbon paper, carbon cloth) in terms of macro and micro porous structure, surface properties, transport properties (hydraulic permeability, mass transfer coefficients, MacMullin number) as well as electrochemical performance. Besides, the use of some novel electrodes, such as brush structured carbon materials, in RFBs will also be disclosed in the present work. With the present comprehensive comparison study, insights on future electrode design and engineering direction will be discussed at last. [1] A.Z. Weber, M.M. Mench, J.P. Meyers, P.N. Ross, J.T. Gostick, Q. Liu, J.Appl.Electrochem. 41 (2011) 1137-1164. [2] M.L. Perry, A.Z. Weber, J.Electrochem.Soc. 163 (2016) A5064-A5067. [3] B.R. Chalamala, T. Soundappan, G.R. Fisher, M.R. Anstey, V.V. Viswanathan, M.L. Perry, Proc IEEE. 102 (2014) 976-999.