BACKGROUND Although nonpharmacological interventions(NPI) for irritable bowel syndrome(IBS) have been applied clinically, their relative efficacy and safety are poorly understood.AIM To compare and rank different NPI ...BACKGROUND Although nonpharmacological interventions(NPI) for irritable bowel syndrome(IBS) have been applied clinically, their relative efficacy and safety are poorly understood.AIM To compare and rank different NPI in the treatment of IBS.METHODS Five electronic databases were searched from their inception to January 12, 2020. Data of included publications were analyzed using network meta-analysis(NMA). Quality of endpoints were assessed by tools of the Cochrane Handbook and the GRADEpro software. Pooled relative risk or standardized mean difference with their corresponding 95% confidence intervals were used for statistical analysis. Surface under the cumulative ranking curve(SUCRA) probability value was conducted to rank the examined interventions. Sensitivity analysis was performed to verify the robustness of results and test the source of heterogeneity.RESULTS Forty randomized controlled trials with 4196 participants were included in this NMA. Compared with routine pharmacotherapies and placebo, acupuncture and cognitive behavioral therapy(CBT) had better efficacy in relieving IBS symptoms. Based on the SUCRA values, acupuncture ranked first in improving overall clinical efficacy and avoiding adverse effects. CBT ranked first in lowering the scores of IBS symptom severity scale, self-rating anxiety scale and self-rating depression scale.CONCLUSION This study confirmed the efficacy and safety of NPI for improving IBS symptoms, which to some extent recommended several interventions for clinical practice.展开更多
Lithium-sulfur(Li-S) battery is considered as a promising energy storage system to realize high energy density.Nevertheless,unstable lithium metal anode emerges as the bottleneck toward practical applications,especial...Lithium-sulfur(Li-S) battery is considered as a promising energy storage system to realize high energy density.Nevertheless,unstable lithium metal anode emerges as the bottleneck toward practical applications,especially with limited anode excess required in a working full cell.In this contribution,a mixed diisopropyl ether-based(mixed-DIPE) electrolyte was proposed to effectively protect lithium metal anode in Li-S batteries with sulfurized polyacrylonitrile(SPAN) cathodes.The mixed-DIPE electrolyte improves the compatibility to lithium metal and suppresses the dissolution of lithium polysulfides,rendering significantly improved cycling stability.Concretely,Li | Cu half-cells with the mixed-DIPE electrolyte cycled stably for 120 cycles,which is nearly five times longer than that with routine carbonate-based electrolyte.Moreover,the mixedDIPE electrolyte contributed to a doubled life span of 156 cycles at 0.5 C in Li | SPAN full cells with ultrathin 50 μm Li metal anodes compared with the routine electrolyte.This contribution affords an effective electrolyte formula for Li metal anode protection and is expected to propel the practical applications of high-energy-density Li-S batteries.展开更多
Lithium–sulfur(Li–S)batteries are highly regarded as next-generation energy storage devices due to their ultrahigh theoretical energy density of 2600 Wh kg^(−1).However,practical high-energy-density Li–S pouch cell...Lithium–sulfur(Li–S)batteries are highly regarded as next-generation energy storage devices due to their ultrahigh theoretical energy density of 2600 Wh kg^(−1).However,practical high-energy-density Li–S pouch cells suffer from limited cycling lifespan with rapid loss of active materials.Herein,systematic evaluation on a 400 Wh kg^(−1)Li–S pouch cell is carried out to reveal the working and failure mechanism of Li–S batteries under practical conditions.Electrode morphology,spatial distribution and species analysis of sulfur,and capacity retention of electrodes are respectively evaluated after the first cycle of discharge or charge.Considerable lithium polysulfides are found in electrolyte even at the end of discharge or charge,where the sulfur redox reactions are reversible with high capacity retention.Meanwhile,severe morphology change is identified on lithium metal anode,yet there remains substantial active lithium to support the following cycles.This work not only demonstrates unique behaviors of Li–S batteries under practical conditions,which is essential for promoting the progress of Li–S pouch cells,but also affords a systematic evaluation methodology to guide further investigation on high-energy-density Li–S batteries.展开更多
基金Supported by National Natural Science Foundation of China, No.81774238, No. 81373563, and No.30772689Construction of Chinese First-class Discipline of Guangzhou University of Chinese Medicine, 2017, No.70+2 种基金Construction of Chinese First-class Discipline Research of Key Project of Guangzhou University of Chinese Medicine([2020] No. 62,[2019] No. 5, and[2018] No. 6)Construction of High-level University of Guangzhou University of Chinese Medicine(2016, No. 64)Innovation Team to Foster Scientific Research Projects of Guangzhou University of Chinese Medicine, No.2016KYTD07。
文摘BACKGROUND Although nonpharmacological interventions(NPI) for irritable bowel syndrome(IBS) have been applied clinically, their relative efficacy and safety are poorly understood.AIM To compare and rank different NPI in the treatment of IBS.METHODS Five electronic databases were searched from their inception to January 12, 2020. Data of included publications were analyzed using network meta-analysis(NMA). Quality of endpoints were assessed by tools of the Cochrane Handbook and the GRADEpro software. Pooled relative risk or standardized mean difference with their corresponding 95% confidence intervals were used for statistical analysis. Surface under the cumulative ranking curve(SUCRA) probability value was conducted to rank the examined interventions. Sensitivity analysis was performed to verify the robustness of results and test the source of heterogeneity.RESULTS Forty randomized controlled trials with 4196 participants were included in this NMA. Compared with routine pharmacotherapies and placebo, acupuncture and cognitive behavioral therapy(CBT) had better efficacy in relieving IBS symptoms. Based on the SUCRA values, acupuncture ranked first in improving overall clinical efficacy and avoiding adverse effects. CBT ranked first in lowering the scores of IBS symptom severity scale, self-rating anxiety scale and self-rating depression scale.CONCLUSION This study confirmed the efficacy and safety of NPI for improving IBS symptoms, which to some extent recommended several interventions for clinical practice.
基金supported by National Key Research and Development Program(2016YFA0202500 and 2016YFA0200102)National Natural Science Foundation of China(21776019,21825501,and U1801257)the Tsinghua University Initiative Scientific Research Program
文摘Lithium-sulfur(Li-S) battery is considered as a promising energy storage system to realize high energy density.Nevertheless,unstable lithium metal anode emerges as the bottleneck toward practical applications,especially with limited anode excess required in a working full cell.In this contribution,a mixed diisopropyl ether-based(mixed-DIPE) electrolyte was proposed to effectively protect lithium metal anode in Li-S batteries with sulfurized polyacrylonitrile(SPAN) cathodes.The mixed-DIPE electrolyte improves the compatibility to lithium metal and suppresses the dissolution of lithium polysulfides,rendering significantly improved cycling stability.Concretely,Li | Cu half-cells with the mixed-DIPE electrolyte cycled stably for 120 cycles,which is nearly five times longer than that with routine carbonate-based electrolyte.Moreover,the mixedDIPE electrolyte contributed to a doubled life span of 156 cycles at 0.5 C in Li | SPAN full cells with ultrathin 50 μm Li metal anodes compared with the routine electrolyte.This contribution affords an effective electrolyte formula for Li metal anode protection and is expected to propel the practical applications of high-energy-density Li-S batteries.
基金supported by the Beijing Natural Science Foundation(JQ20004)National Natural Science Foundation of China(U1801257)the Scientific and Technological Key Project of Shanxi Province(20191102003)。
文摘Lithium–sulfur(Li–S)batteries are highly regarded as next-generation energy storage devices due to their ultrahigh theoretical energy density of 2600 Wh kg^(−1).However,practical high-energy-density Li–S pouch cells suffer from limited cycling lifespan with rapid loss of active materials.Herein,systematic evaluation on a 400 Wh kg^(−1)Li–S pouch cell is carried out to reveal the working and failure mechanism of Li–S batteries under practical conditions.Electrode morphology,spatial distribution and species analysis of sulfur,and capacity retention of electrodes are respectively evaluated after the first cycle of discharge or charge.Considerable lithium polysulfides are found in electrolyte even at the end of discharge or charge,where the sulfur redox reactions are reversible with high capacity retention.Meanwhile,severe morphology change is identified on lithium metal anode,yet there remains substantial active lithium to support the following cycles.This work not only demonstrates unique behaviors of Li–S batteries under practical conditions,which is essential for promoting the progress of Li–S pouch cells,but also affords a systematic evaluation methodology to guide further investigation on high-energy-density Li–S batteries.
