Large anions exhibit slow diffusion kinetics in graphite cathode of dual-ion batteries(DIBs);particularly at high current density,it suffers severely from the largely-reduced interlayer utilization of graphite cathode...Large anions exhibit slow diffusion kinetics in graphite cathode of dual-ion batteries(DIBs);particularly at high current density,it suffers severely from the largely-reduced interlayer utilization of graphite cathode,which as a bottleneck limits the fast charge application of DIBs.To maximize interlayer utilization and achieve faster anion diffusion kinetics,a fast and uncrowded anion transport channel must be established.Herein,Li^(+)was pre-intercalated into the graphite paper(GP)cathode to increase the interlayer spacing,and then hosted for the PF_(6)^(-)anion storage.Combined with theoretical calculation,it shows that the local interlayer spacing enlargement and the residual Li^(+)reduce the anion intercalation energy and diffusion barrier,leading to better rate stability.The obtained GP with Li^(+)pre-intercalation(GP-Li)electrode exhibits a discharge capacity of 23.1 m Ah g^(-1) at a high current of 1300 m A g^(-1).This work provides a facile method to efficiently improve the interlayer utilization of graphite cathode at large currents.展开更多
Oxygen evolution reaction(OER)is a bottleneck half-reaction in many important energy conversion processes(e.g.,water splitting),and one of the key issues lies to develop high-efficiency,cost-effective OER electrocatal...Oxygen evolution reaction(OER)is a bottleneck half-reaction in many important energy conversion processes(e.g.,water splitting),and one of the key issues lies to develop high-efficiency,cost-effective OER electrocatalysts.Rather than those popular extrinsic modulations of any catalysts with gradually degraded performance,we aim at the utilization of the intermediates offered from the undergoing OER as long-standing electrocatalysts.Herein,by inverted design,we extracted the bimetallic borides(FeCoB_(2))-derived intermediates metal borates in the OER,unlocking their potential as a selffunctionalized highly active catalytic phase in-situ formed on the metal boride surface for continuing OER operation.Mechanistically,the surface metal atoms are oxidized to oxyhydroxides,and the surface metalloids(B)are further transformed to the corresponding oxoanions to form metal borates.Such OER self-produced electrocatalyst exhibits a small overpotential of 295 mV at 10 mA/cm2 and its high catalytic activity lasts even after 200 h.Compared with FeCoB_(2),the catalytic activity of this electrochemically activated FeCoB_(2) is~7 times higher.The in-situ formed metal borate is dominatingly responsible for the obtained high catalytic activity.Such unique OER-produced self-functionalization surfaces of metal borates afford to greatly reduce the energy barrier of the continuing OER,thereby accelerating the reaction process.展开更多
The poor stability of non-noble metal catalysts in oxygen reduction reaction(ORR) is a main bottleneck that limits their big-scale application in metal-air batteries. Herein, we construct a chainmail catalyst(Co-NC-AD...The poor stability of non-noble metal catalysts in oxygen reduction reaction(ORR) is a main bottleneck that limits their big-scale application in metal-air batteries. Herein, we construct a chainmail catalyst(Co-NC-AD) with outstanding stability, via the competitive complexation and post absorption strategy,consisting of highly graphitic layers wrapped uniform-size Co nanoparticles(Co-NPs). Experiments combined with density functional theory(DFT) calculations jointly confirmed that the electron transfer occurred from the inner Co-NPs to the external graphitic layers. It facilitated the adsorption process of oxygen molecules and the hybridization of the O-2 p and C-1 p orbitals, which accelerated the ORR reaction kinetics. Consequently, our prepared Co-NC-AD shows excellent ORR activity, offered with a more positive initial potential(E_(onset)= 0.95 V) and half-wave potential(E_(1/2)= 0.86 V). The remarkable stability and resistance of methanol poisoning are merited from the protection effect of stable graphitic layers. In addition, the high electrochemical performance of Co-NC-AD-based zinc-air battery demonstrates their potential for practical applications. Therefore, our work provides new ideas for the design of nanoconfined catalysts with high stability and activity.展开更多
[Objectives]This study was conducted to investigate the effects of boron fertilizer on the root system and nutrient contents of yacon.[Methods]By the field test method,high-and low-dose of boron fertilizer(Na2B8O13,90...[Objectives]This study was conducted to investigate the effects of boron fertilizer on the root system and nutrient contents of yacon.[Methods]By the field test method,high-and low-dose of boron fertilizer(Na2B8O13,9000 and 3000 g/hm2)and equal amount of clean water(CK)were sprayed 3 times in the soil area where plants were grown in the early,middle and late stages of yacon growth,and the effects of applying boron fertilizer on the growth and fruit quality of yacon were analyzed.[Results]The indexes of the root system of yacon treated with boron fertilizer were significantly higher than those of the CK.The yield and total sugar,vitamin C,ash,Ca,Fe,Zn and other nutrients of the boron fertilizer treatments increased significantly compared with the CK.The yields of the low-and high-dose treatments increased by 77.2%and 211.2%,respectively,compared with the CK;and the contents of total sugar,vitamin C,ash,Ca,Fe and Zn in the high-dose treatment increased by 28.4%,163.6%,33.2%,73.3%,41.2%and 56.2%,respectively,compared with the CK.The nutrients in yacon treated with the low dose of boron fertilizer were lower than those with the high dose.The application of boron fertilizer could increase the yield of yacon,improve its quality and increase the contents of nutrients such as Ca,Fe,Zn and total sugar.[Conclusions]This study provides a reference for the reasonable application of boron fertilizer in the production of yacon and the improvement of the quality of yacon.展开更多
It is challenging for precise governing of electronic configuration of the individually-atomic catalysts toward optimal electrocatalysis,as d-band configuration of a metal center determines the adsorption behavior of ...It is challenging for precise governing of electronic configuration of the individually-atomic catalysts toward optimal electrocatalysis,as d-band configuration of a metal center determines the adsorption behavior of reactive species to the center in oxygen reduction reaction(ORR).The addition of Cu atom modifies the d-band center position of Fe central atom,thus strengthening the d-π*orbital interactions.Herein,FeCu-NC catalyst in the nitrogen-doped carbon(NC)support containing individual dual-metal CuN4/FeN4 sites was prepared by the surface confinement strategy of zeolitic imidazolate framework(ZIF),treated as a model catalyst.Experimentally and theoretically co-verified dual-metal CuN4/FeN4 sites highly dispersed in the NC support,enable transferring more electrons from FeN4 sites to*OH intermediates,thereby accelerating the desorption process of*OH species.Superior to those commercial Pt/C,Our FeCu-NC catalyst exhibited extraordinary ORR activity(with a E1/2 as high as 0.87 V)and cycling stability in 0.1 M KOH electrolyte,and thereof demonstrated excellent discharge performance in zinc-air batteries.Our construction of dual-atom catalysts(DACs)provides a strategy for atom-by-atom designing high-efficiency catalysts via orbital regulation.展开更多
Programmed cell death 4 (PDCD4) is a RNA-binding protein that acts as a tumor suppressor in many cancer types, including colorectal cancer (CRC). During CRC carcinogenesis, PDCD4 protein levels remarkably decrease...Programmed cell death 4 (PDCD4) is a RNA-binding protein that acts as a tumor suppressor in many cancer types, including colorectal cancer (CRC). During CRC carcinogenesis, PDCD4 protein levels remarkably decrease, but the underlying molecular mechanism for decreased PDCD4 expression is not fully understood. In this study, we performed bioinformatics analysis to identify miRNAs that potentially target PDCD4. We demonstrated miR-181b as a direct regulator of PDCD4. We further showed that activation of IL6/STAT3 signaling pathway increased miR-181b expression and conse- quently resulted in downregulation of PDCD4 in CRC cells. In addition, we investigated the biological effects of PDCD4 inhibition by miR-181b both in vitro and in vivo and found that miR-181b could promote cell proliferation and migration and suppress apoptosis in CRC cells and accelerate tumor growth in xenograft mice, potentially through targeting PDCD4. Taken toge- ther, this study highlights an oncomiR role for miR-181b in regulating PDCD4 in CRC and suggests that miR-181b may be a novel molecular therapeutic target for CRC.展开更多
Myocardial regeneration has been considered a promising option for the treatment of adult myocardial injuries.Previously,a chick early amniotic fluid(ceAF)preparation was shown to contain growth-related factors that p...Myocardial regeneration has been considered a promising option for the treatment of adult myocardial injuries.Previously,a chick early amniotic fluid(ceAF)preparation was shown to contain growth-related factors that pro-moted embryonic growth and cellular proliferation,though the nature of the components within ceAF were not fully defined.Here we tested whether this ceAF preparation is similarly effective in the promotion of myocardial regen-eration,which could provide an alternative therapeutic for intervening myocardial injury.In this study,a myocardial ischemic injury model was established in adult mice and pigs by multiple research entities,and we were able to show that ceAF can efficiently rescue damaged cardiac tissues and markedly improve cardiac function in both experimental models through intravenous administration.ceAF administration increased cell proliferation and improved angio-genesis,likely via down-regulation of Hippo-YAP signaling.Our data suggest that ceAF administration can effectively rescue ischemic heart injury,providing the key functional information for the further development of ceAF for use in attenuating myocardial injury.展开更多
Dear Editor,Dilated cardiomyopathy(DCM)is a common form of inherited cardiomyopathy.In the past decades,single mutations in various genes encoding sarcomeric,cytoskeletal,and channel proteins etc.have been found to be...Dear Editor,Dilated cardiomyopathy(DCM)is a common form of inherited cardiomyopathy.In the past decades,single mutations in various genes encoding sarcomeric,cytoskeletal,and channel proteins etc.have been found to be associated with DCM(Hershberger et al.,2013;McNally and Mestroni,2017).However,the mechanisms how single mutations in sarcomeric or structural genes lead to the disease remain elusive.An interesting phenomenon often seen in familial cardiomyopathy is that different single mutations on the same gene can cause either DCM or hypertrophic cardiomyopathy(HCM)(Kathiresan and Srivastava,2012),which exhibit almost opposite disease phenotypes.DCM is characterized by thinned myocardium and septum,ventricular chamber dilation,and systolic dysfunction(Jefferies and Towbin,2010;McNally and Mestroni,2017),while HCM exhibits thickened myocardium and septum,reduced ventricular chamber,and diastolic dysfunction(Richard et al.,2003).At the cellular level,HCM cardiomyocytes exhibit concentric hypertrophy characterized by assembly of myofilaments in parallel and widening of the myocytes.In contrast,DCM cardiomyocytes show eccentric hypertrophy,with assembly of the myofilaments in series and myocyte elongation(Kehat and Molkentin,2010).展开更多
基金financially supported by the National Natural Science Foundation of China(51932003,51872115)the 2020 International Cooperation Project of the Department of Science and Technology of Jilin Province(20200801001GH)the Project supported by State Key Laboratory of Luminescence and Applications(KLA-2020-05)。
文摘Large anions exhibit slow diffusion kinetics in graphite cathode of dual-ion batteries(DIBs);particularly at high current density,it suffers severely from the largely-reduced interlayer utilization of graphite cathode,which as a bottleneck limits the fast charge application of DIBs.To maximize interlayer utilization and achieve faster anion diffusion kinetics,a fast and uncrowded anion transport channel must be established.Herein,Li^(+)was pre-intercalated into the graphite paper(GP)cathode to increase the interlayer spacing,and then hosted for the PF_(6)^(-)anion storage.Combined with theoretical calculation,it shows that the local interlayer spacing enlargement and the residual Li^(+)reduce the anion intercalation energy and diffusion barrier,leading to better rate stability.The obtained GP with Li^(+)pre-intercalation(GP-Li)electrode exhibits a discharge capacity of 23.1 m Ah g^(-1) at a high current of 1300 m A g^(-1).This work provides a facile method to efficiently improve the interlayer utilization of graphite cathode at large currents.
基金Financially supported by the National Natural Science Foundation of China(51872115,52101256,51932003)China Postdoctoral Science Foundation Project(2020M680043)+1 种基金Science and Technology Research Project of the Department of Education of Jilin Province(JJKH20211083KJ)2020 International Cooperation Project of the Department of Science and Technology of Jilin Province(20200801001GH)。
文摘Oxygen evolution reaction(OER)is a bottleneck half-reaction in many important energy conversion processes(e.g.,water splitting),and one of the key issues lies to develop high-efficiency,cost-effective OER electrocatalysts.Rather than those popular extrinsic modulations of any catalysts with gradually degraded performance,we aim at the utilization of the intermediates offered from the undergoing OER as long-standing electrocatalysts.Herein,by inverted design,we extracted the bimetallic borides(FeCoB_(2))-derived intermediates metal borates in the OER,unlocking their potential as a selffunctionalized highly active catalytic phase in-situ formed on the metal boride surface for continuing OER operation.Mechanistically,the surface metal atoms are oxidized to oxyhydroxides,and the surface metalloids(B)are further transformed to the corresponding oxoanions to form metal borates.Such OER self-produced electrocatalyst exhibits a small overpotential of 295 mV at 10 mA/cm2 and its high catalytic activity lasts even after 200 h.Compared with FeCoB_(2),the catalytic activity of this electrochemically activated FeCoB_(2) is~7 times higher.The in-situ formed metal borate is dominatingly responsible for the obtained high catalytic activity.Such unique OER-produced self-functionalization surfaces of metal borates afford to greatly reduce the energy barrier of the continuing OER,thereby accelerating the reaction process.
基金supported by the National Natural Science Foundation of China(51872115,51932003)the 2020 International Cooperation Project of the Department of Science and Technology of Jilin Province(20200801001GH)+1 种基金the Project supported by State Key Laboratory of Luminescence and Applications(KLA-2020-05)the Project for Self-innovation Capability Construction of Jilin Province Development and Reform Commission(2021C026)。
文摘The poor stability of non-noble metal catalysts in oxygen reduction reaction(ORR) is a main bottleneck that limits their big-scale application in metal-air batteries. Herein, we construct a chainmail catalyst(Co-NC-AD) with outstanding stability, via the competitive complexation and post absorption strategy,consisting of highly graphitic layers wrapped uniform-size Co nanoparticles(Co-NPs). Experiments combined with density functional theory(DFT) calculations jointly confirmed that the electron transfer occurred from the inner Co-NPs to the external graphitic layers. It facilitated the adsorption process of oxygen molecules and the hybridization of the O-2 p and C-1 p orbitals, which accelerated the ORR reaction kinetics. Consequently, our prepared Co-NC-AD shows excellent ORR activity, offered with a more positive initial potential(E_(onset)= 0.95 V) and half-wave potential(E_(1/2)= 0.86 V). The remarkable stability and resistance of methanol poisoning are merited from the protection effect of stable graphitic layers. In addition, the high electrochemical performance of Co-NC-AD-based zinc-air battery demonstrates their potential for practical applications. Therefore, our work provides new ideas for the design of nanoconfined catalysts with high stability and activity.
基金School-level Scientific Research Fund Project of Guizhou Normal University(2017BS007)。
文摘[Objectives]This study was conducted to investigate the effects of boron fertilizer on the root system and nutrient contents of yacon.[Methods]By the field test method,high-and low-dose of boron fertilizer(Na2B8O13,9000 and 3000 g/hm2)and equal amount of clean water(CK)were sprayed 3 times in the soil area where plants were grown in the early,middle and late stages of yacon growth,and the effects of applying boron fertilizer on the growth and fruit quality of yacon were analyzed.[Results]The indexes of the root system of yacon treated with boron fertilizer were significantly higher than those of the CK.The yield and total sugar,vitamin C,ash,Ca,Fe,Zn and other nutrients of the boron fertilizer treatments increased significantly compared with the CK.The yields of the low-and high-dose treatments increased by 77.2%and 211.2%,respectively,compared with the CK;and the contents of total sugar,vitamin C,ash,Ca,Fe and Zn in the high-dose treatment increased by 28.4%,163.6%,33.2%,73.3%,41.2%and 56.2%,respectively,compared with the CK.The nutrients in yacon treated with the low dose of boron fertilizer were lower than those with the high dose.The application of boron fertilizer could increase the yield of yacon,improve its quality and increase the contents of nutrients such as Ca,Fe,Zn and total sugar.[Conclusions]This study provides a reference for the reasonable application of boron fertilizer in the production of yacon and the improvement of the quality of yacon.
基金supported by the National Natural Science Foundation of China(Nos.51872115 and 52272209)2020 International Cooperation Project of the Department of Science and Technology of Jilin Province(No.20200801001GH).
文摘It is challenging for precise governing of electronic configuration of the individually-atomic catalysts toward optimal electrocatalysis,as d-band configuration of a metal center determines the adsorption behavior of reactive species to the center in oxygen reduction reaction(ORR).The addition of Cu atom modifies the d-band center position of Fe central atom,thus strengthening the d-π*orbital interactions.Herein,FeCu-NC catalyst in the nitrogen-doped carbon(NC)support containing individual dual-metal CuN4/FeN4 sites was prepared by the surface confinement strategy of zeolitic imidazolate framework(ZIF),treated as a model catalyst.Experimentally and theoretically co-verified dual-metal CuN4/FeN4 sites highly dispersed in the NC support,enable transferring more electrons from FeN4 sites to*OH intermediates,thereby accelerating the desorption process of*OH species.Superior to those commercial Pt/C,Our FeCu-NC catalyst exhibited extraordinary ORR activity(with a E1/2 as high as 0.87 V)and cycling stability in 0.1 M KOH electrolyte,and thereof demonstrated excellent discharge performance in zinc-air batteries.Our construction of dual-atom catalysts(DACs)provides a strategy for atom-by-atom designing high-efficiency catalysts via orbital regulation.
文摘Programmed cell death 4 (PDCD4) is a RNA-binding protein that acts as a tumor suppressor in many cancer types, including colorectal cancer (CRC). During CRC carcinogenesis, PDCD4 protein levels remarkably decrease, but the underlying molecular mechanism for decreased PDCD4 expression is not fully understood. In this study, we performed bioinformatics analysis to identify miRNAs that potentially target PDCD4. We demonstrated miR-181b as a direct regulator of PDCD4. We further showed that activation of IL6/STAT3 signaling pathway increased miR-181b expression and conse- quently resulted in downregulation of PDCD4 in CRC cells. In addition, we investigated the biological effects of PDCD4 inhibition by miR-181b both in vitro and in vivo and found that miR-181b could promote cell proliferation and migration and suppress apoptosis in CRC cells and accelerate tumor growth in xenograft mice, potentially through targeting PDCD4. Taken toge- ther, this study highlights an oncomiR role for miR-181b in regulating PDCD4 in CRC and suggests that miR-181b may be a novel molecular therapeutic target for CRC.
基金This work was supported by ZheJiang HygeianCells Biomedical Co.Ltd.,Hangzhou,Zhejiang,310019,China.
文摘Myocardial regeneration has been considered a promising option for the treatment of adult myocardial injuries.Previously,a chick early amniotic fluid(ceAF)preparation was shown to contain growth-related factors that pro-moted embryonic growth and cellular proliferation,though the nature of the components within ceAF were not fully defined.Here we tested whether this ceAF preparation is similarly effective in the promotion of myocardial regen-eration,which could provide an alternative therapeutic for intervening myocardial injury.In this study,a myocardial ischemic injury model was established in adult mice and pigs by multiple research entities,and we were able to show that ceAF can efficiently rescue damaged cardiac tissues and markedly improve cardiac function in both experimental models through intravenous administration.ceAF administration increased cell proliferation and improved angio-genesis,likely via down-regulation of Hippo-YAP signaling.Our data suggest that ceAF administration can effectively rescue ischemic heart injury,providing the key functional information for the further development of ceAF for use in attenuating myocardial injury.
文摘Dear Editor,Dilated cardiomyopathy(DCM)is a common form of inherited cardiomyopathy.In the past decades,single mutations in various genes encoding sarcomeric,cytoskeletal,and channel proteins etc.have been found to be associated with DCM(Hershberger et al.,2013;McNally and Mestroni,2017).However,the mechanisms how single mutations in sarcomeric or structural genes lead to the disease remain elusive.An interesting phenomenon often seen in familial cardiomyopathy is that different single mutations on the same gene can cause either DCM or hypertrophic cardiomyopathy(HCM)(Kathiresan and Srivastava,2012),which exhibit almost opposite disease phenotypes.DCM is characterized by thinned myocardium and septum,ventricular chamber dilation,and systolic dysfunction(Jefferies and Towbin,2010;McNally and Mestroni,2017),while HCM exhibits thickened myocardium and septum,reduced ventricular chamber,and diastolic dysfunction(Richard et al.,2003).At the cellular level,HCM cardiomyocytes exhibit concentric hypertrophy characterized by assembly of myofilaments in parallel and widening of the myocytes.In contrast,DCM cardiomyocytes show eccentric hypertrophy,with assembly of the myofilaments in series and myocyte elongation(Kehat and Molkentin,2010).