The spontaneous bursts of electrical activity in the developing auditory system are derived from the periodic release of adenosine triphosphate(ATP)by supporting cells in the Kölliker’s organ.However,the mechani...The spontaneous bursts of electrical activity in the developing auditory system are derived from the periodic release of adenosine triphosphate(ATP)by supporting cells in the Kölliker’s organ.However,the mechanisms responsible for initiating spontaneous ATP release have not been determined.Our previous study revealed that telomerase reverse transcriptase(TERT)is expressed in the basilar membrane during the first postnatal week.Its role in cochlear development remains unclear.In this study,we investigated the expression and role of TERT in postnatal cochlea supporting cells.Our results revealed that in postnatal cochlear Kölliker’s organ supporting cells,TERT shifts from the nucleus into the cytoplasm over time.We found that the TERT translocation tendency in postnatal cochlear supporting cells in vitro coincided with that observed in vivo.Further analysis showed that TERT in the cytoplasm was mainly located in mitochondria in the absence of oxidative stress or apoptosis,suggesting that TERT in mitochondria plays roles other than antioxidant or anti-apoptotic functions.We observed increased ATP synthesis,release and activation of purine signaling systems in supporting cells during the first 10 postnatal days.The phenomenon that TERT translocation coincided with changes in ATP synthesis,release and activation of the purine signaling system in postnatal cochlear supporting cells suggested that TERT may be involved in regulating ATP release and activation of the purine signaling system.Our study provides a new research direction for exploring the spontaneous electrical activity of the cochlea during the early postnatal period.展开更多
Poly(ethylene oxide)(PEO)-based solid polymer electrolyte(SPE)is considered as a promising solid-state electrolyte for all-solid-state lithium batteries(ASSLBs).Nevertheless,the poor interfacial stability with high-vo...Poly(ethylene oxide)(PEO)-based solid polymer electrolyte(SPE)is considered as a promising solid-state electrolyte for all-solid-state lithium batteries(ASSLBs).Nevertheless,the poor interfacial stability with high-voltage cathode materials(e.g.,LiCoO_(2))restricts its application in high energy density solid-state batteries.Herein,high-voltage stable Li_(3)AlF_(6) protective layer is coated on the surface of LiCoO_(2) particle to improve the performance and investigate the failure mechanism of PEO-based ASSLBs.The phase transition unveils that chemical redox reaction occurs between the highly reactive LiCoO_(2) surface and PEO-based SPE,resulting in structure collapse of LiCoO_(2),hence the poor cycle performance of PEO-based ASSLBs with LiCoO_(2) at charging voltage of 4.2 V vs Li/Li+.By sharp contrast,no obvious structure change can be found at the surface of Li_(3)AlF_(6)-coated LiCoO_(2),and the original layered phase was well retained.When the charging voltage reaches up to 4.5 V vs Li/Li+,the intensive electrochemical decomposition of PEO-based SPE occurs,leading to the constant increase of cell impedance and directly causing the poor performance.This work not only provides important supplement to the failure mechanism of PEO-based batter-ies with LiCoO_(2),but also presents a universal strategy to retain structure stability of cathode-electrolyte interface in high-voltage ASSLBs.展开更多
After germination in the dark,plants produce a shoot apical hook and closed cotyledons to protect the quiescent shoot apical meristem(SAM),which is critical for seedling survival during skotomorphogenesis.The factors ...After germination in the dark,plants produce a shoot apical hook and closed cotyledons to protect the quiescent shoot apical meristem(SAM),which is critical for seedling survival during skotomorphogenesis.The factors that coordinate these processes,particularly SAM repression,remain enigmatic.Plant cuticles,multilayered structures of lipid components on the outermost surface of the aerial epidermis of all land plants,provide protection against desiccation and external environmental stresses.Whether and how cuticles regulate plant development are still unclear.Here,we demonstrate that mutants of BODYGUARD1(BDG1)and long-chain acyl-CoA synthetase2(LACS2),key genes involved in cutin biosynthesis,produce a short hypocotyl with an opened apical hook and cotyledons in which the SAM is activated during skotomorphogenesis.Light signaling represses expression of BDG1 and LACS2,as well as cutin biosynthesis.Transcriptome analysis revealed that cuticles are critical for skotomorphogenesis,particularly for the development and function of chloroplasts.Genetic and molecular analyses showed that decreased HOOKLESS1 expression results in apical hook opening in the mutants.When hypoxia-induced expression of LITTLE ZIPPER2 at the SAM promotes organ initiation in the mutants,the de-repressed expression of cell-cycle genes and the cytokinin response induce the growth of true leaves.Our results reveal previously unrecognized developmental functions of the plant cuticle during skotomorphogenesis and demonstrate a mechanism by which light initiates photomorphogenesis through dynamic regulation of cuticle synthesis to induce coordinated and systemic changes in organ development and growth during the skotomorphogenesis-to-photomorphogenesis transition.展开更多
Two-dimensional ferromagnetic(2DFM)semiconductors(metals,half-metals,and so on)are important materials fornext-generation nano-electronic and nano-spintronic devices.However,these kinds of materials remain scarce,“tr...Two-dimensional ferromagnetic(2DFM)semiconductors(metals,half-metals,and so on)are important materials fornext-generation nano-electronic and nano-spintronic devices.However,these kinds of materials remain scarce,“trial anderror”experiments and calculations are both time-consumingand expensive.In the present work,in order to obtain theoptimal 2DFM materials with strong magnetization,a machinelearning(ML)framework was established to search the 2Dmaterial space containing over 2417 samples and identified 615compounds whose magnetic orders were then determined viahigh-throughput first-principles calculations.With the adoptionof ML algorithms,two classification models and a regressionmodel were trained.The interpretability of the regressionmodel was evaluated through Shapley Additive exPlanations(SHAP)analysis.Unexpectedly,it is found that Cr2NF2 is apotential antiferromagnetic ferroelectric 2D multiferroic material.More importantly,60 novel 2DFM candidates werepredicted,and among them,13 candidates have magnetic moments of>7μB.Os2Cl8,Fe3GeSe2,and Mn4N3S2 were predictedto be novel 2DFM semiconductors,metals,and half-metals,respectively.With the adoption of the ML approach in thecurrent work,the prediction of 2DFM materials with strongmagnetization can be accelerated,and the computation timecan be drastically reduced by more than one order ofmagnitude.展开更多
Lithium(Li)metal is one of the most promising anodes for next-generation energy storage systems.However,the Li dendrite formation and unstable solid-electrolyte interface(SEI)have hindered its further application.Lith...Lithium(Li)metal is one of the most promising anodes for next-generation energy storage systems.However,the Li dendrite formation and unstable solid-electrolyte interface(SEI)have hindered its further application.Lithium nitrate(LiNO3)is extensively used as an effective electrolyte additive in ether-based electrolytes to improve the stability of lithium metal.Nevertheless,it is rarely utilized in carbonate electrolytes due to its low solubility.Here,a novel gel polymer electrolyte(GPE)consisting of poly(vinylidene fluoride)(PVDF),poly(methyl methacrylate)(PMMA),poly(ethylene oxide)(PEO)with LiN03 additive is proposed to solve this issue.In this GPE,polyether-based PEO serves as a matrix for dissolving LiNO3 which can be decomposed into a fast Li-ion conductor(Li3N)in conventional carbonate electrolytes to enhance the stability and Li^+conductivity of the SEI film.As a result,dendrite formation is effectively suppressed,and a significantly improved average Coulombic efficiency(CE)of 97.2%in Li-Cu cell is achieved.By using this novel GPE coupled with Li anode and LiNi0.5Mn0.3Co0.2O2(NMC532),excellent capacity retention of 94.1%and high average CE of over 99.2%are obtained after 200 cycles at 0.5 C.This work presents fresh insight into practical modification strategies on high-voltage Li metal batteries.展开更多
Succinonitrile(SN)based solid-state electrolytes(SSEs)have potential applications in lithium(Li)batteries due to their ease of preparation and high ionic conductivity at room temperature.Here,a novel SSE consisting of...Succinonitrile(SN)based solid-state electrolytes(SSEs)have potential applications in lithium(Li)batteries due to their ease of preparation and high ionic conductivity at room temperature.Here,a novel SSE consisting of poly(vinylidene fluoride-hexafluoropropy-lene)(PVDF-HFP),poly(methyl methacrylate)(PMMA)and Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3) with SN is fabricated,where PMMA is added to serve as a polymer matrix for better wettability of SN.Due to the addition of PMMA,improved room-temperature ionic conductivity of the SSE is resulted.More importantly,better interfacial contact as well as more stable solid-state electrolyte(SEI)layer between SSE and Li anode can be also obtained.As a result,homogeneous and dendrite-free Li plating can be achieved for over 1000 h in Li symmetric cells.When coupled with LiNi_(0.5)Mn_(0.3)Co_(0.2)O_(2) cathode and Li anode,the proposed SSE delivers excellent cycling stability and rate capability in full-cells.By implementing SSEs with a polymeric wetting agent,this work provides fresh perspectives on stabilizing the interface between SSEs and Li metal anodes.展开更多
A facile one-pot hydrothermal procedure for the synthesis of magnetic greigite was investigated in this work, by using FeSO4, thioacetamide, and a tiny amount of hexamethylenetetramine (HMTA) as starting materials. ...A facile one-pot hydrothermal procedure for the synthesis of magnetic greigite was investigated in this work, by using FeSO4, thioacetamide, and a tiny amount of hexamethylenetetramine (HMTA) as starting materials. The HMTA molecule, which acted as a chelating agent and an oxidant, could not only tune the valence fluctuation of iron ions, but also direct the hydrothermal reaction towards the exclusive for- mation of greigite platelets with hundreds of nanometers in lateral size. In the presence of a static magnetic field during this synthesis, the greigite nano-platelets were apt to congregate to form 3D flower-like microspheres. A set of experiments suggested that the ferrous ions were at first partly oxidized by HMTA to form ferric intermediates, i.e., Fe(OH)3 and Fe2O3. Then excessive ferrous ions, along with the solid in- termediates, reacted with sulfide ions, and finally evolved into greigite, Taken into consideration that a similar process occurred in magnetotactic bacteria, our results may give a hint at the design of biomimetic synthesis strategies to produce nanomaterials, especially the magnetosome-like greigite.展开更多
基金supported by the National Natural Science Foundation of China,Nos.81870732(to DZ),82171161(to DZ),81900933(to YS),and 82000978(to ZL).
文摘The spontaneous bursts of electrical activity in the developing auditory system are derived from the periodic release of adenosine triphosphate(ATP)by supporting cells in the Kölliker’s organ.However,the mechanisms responsible for initiating spontaneous ATP release have not been determined.Our previous study revealed that telomerase reverse transcriptase(TERT)is expressed in the basilar membrane during the first postnatal week.Its role in cochlear development remains unclear.In this study,we investigated the expression and role of TERT in postnatal cochlea supporting cells.Our results revealed that in postnatal cochlear Kölliker’s organ supporting cells,TERT shifts from the nucleus into the cytoplasm over time.We found that the TERT translocation tendency in postnatal cochlear supporting cells in vitro coincided with that observed in vivo.Further analysis showed that TERT in the cytoplasm was mainly located in mitochondria in the absence of oxidative stress or apoptosis,suggesting that TERT in mitochondria plays roles other than antioxidant or anti-apoptotic functions.We observed increased ATP synthesis,release and activation of purine signaling systems in supporting cells during the first 10 postnatal days.The phenomenon that TERT translocation coincided with changes in ATP synthesis,release and activation of the purine signaling system in postnatal cochlear supporting cells suggested that TERT may be involved in regulating ATP release and activation of the purine signaling system.Our study provides a new research direction for exploring the spontaneous electrical activity of the cochlea during the early postnatal period.
基金We acknowledge financial support from The Shenzhen Science and Technology Research Grant(No.JCYJ20200109140416788)Soft Science Research Project of Guangdong Province(No.2017B030301013)The National Natural Science Foundation of China(No.52102200).
文摘Poly(ethylene oxide)(PEO)-based solid polymer electrolyte(SPE)is considered as a promising solid-state electrolyte for all-solid-state lithium batteries(ASSLBs).Nevertheless,the poor interfacial stability with high-voltage cathode materials(e.g.,LiCoO_(2))restricts its application in high energy density solid-state batteries.Herein,high-voltage stable Li_(3)AlF_(6) protective layer is coated on the surface of LiCoO_(2) particle to improve the performance and investigate the failure mechanism of PEO-based ASSLBs.The phase transition unveils that chemical redox reaction occurs between the highly reactive LiCoO_(2) surface and PEO-based SPE,resulting in structure collapse of LiCoO_(2),hence the poor cycle performance of PEO-based ASSLBs with LiCoO_(2) at charging voltage of 4.2 V vs Li/Li+.By sharp contrast,no obvious structure change can be found at the surface of Li_(3)AlF_(6)-coated LiCoO_(2),and the original layered phase was well retained.When the charging voltage reaches up to 4.5 V vs Li/Li+,the intensive electrochemical decomposition of PEO-based SPE occurs,leading to the constant increase of cell impedance and directly causing the poor performance.This work not only provides important supplement to the failure mechanism of PEO-based batter-ies with LiCoO_(2),but also presents a universal strategy to retain structure stability of cathode-electrolyte interface in high-voltage ASSLBs.
基金supported by the National Natural Science Foundation of China(32270340 and 31970824 to X.L.and 32300304 to H.Z.)the project“Fulltime introduction of high-end talent research project”(2020HBQZYC004 and A202105008 to X.L.)from Hebei provincefunding from the Hebei Natural Science Foundation(C2021205013 to X.L.,C2021205043 to L.G.,and C2023205049 to Y.Sun).
文摘After germination in the dark,plants produce a shoot apical hook and closed cotyledons to protect the quiescent shoot apical meristem(SAM),which is critical for seedling survival during skotomorphogenesis.The factors that coordinate these processes,particularly SAM repression,remain enigmatic.Plant cuticles,multilayered structures of lipid components on the outermost surface of the aerial epidermis of all land plants,provide protection against desiccation and external environmental stresses.Whether and how cuticles regulate plant development are still unclear.Here,we demonstrate that mutants of BODYGUARD1(BDG1)and long-chain acyl-CoA synthetase2(LACS2),key genes involved in cutin biosynthesis,produce a short hypocotyl with an opened apical hook and cotyledons in which the SAM is activated during skotomorphogenesis.Light signaling represses expression of BDG1 and LACS2,as well as cutin biosynthesis.Transcriptome analysis revealed that cuticles are critical for skotomorphogenesis,particularly for the development and function of chloroplasts.Genetic and molecular analyses showed that decreased HOOKLESS1 expression results in apical hook opening in the mutants.When hypoxia-induced expression of LITTLE ZIPPER2 at the SAM promotes organ initiation in the mutants,the de-repressed expression of cell-cycle genes and the cytokinin response induce the growth of true leaves.Our results reveal previously unrecognized developmental functions of the plant cuticle during skotomorphogenesis and demonstrate a mechanism by which light initiates photomorphogenesis through dynamic regulation of cuticle synthesis to induce coordinated and systemic changes in organ development and growth during the skotomorphogenesis-to-photomorphogenesis transition.
基金supported by the National NaturalScience Foundation of China(No.U19A2077)Soft ScienceResearch Project of Guangdong Province(No.2017B030301013).
文摘Two-dimensional ferromagnetic(2DFM)semiconductors(metals,half-metals,and so on)are important materials fornext-generation nano-electronic and nano-spintronic devices.However,these kinds of materials remain scarce,“trial anderror”experiments and calculations are both time-consumingand expensive.In the present work,in order to obtain theoptimal 2DFM materials with strong magnetization,a machinelearning(ML)framework was established to search the 2Dmaterial space containing over 2417 samples and identified 615compounds whose magnetic orders were then determined viahigh-throughput first-principles calculations.With the adoptionof ML algorithms,two classification models and a regressionmodel were trained.The interpretability of the regressionmodel was evaluated through Shapley Additive exPlanations(SHAP)analysis.Unexpectedly,it is found that Cr2NF2 is apotential antiferromagnetic ferroelectric 2D multiferroic material.More importantly,60 novel 2DFM candidates werepredicted,and among them,13 candidates have magnetic moments of>7μB.Os2Cl8,Fe3GeSe2,and Mn4N3S2 were predictedto be novel 2DFM semiconductors,metals,and half-metals,respectively.With the adoption of the ML approach in thecurrent work,the prediction of 2DFM materials with strongmagnetization can be accelerated,and the computation timecan be drastically reduced by more than one order ofmagnitude.
基金This work was financially supported by National Key R&D Program of China(No.2016 YFB0700600)Soft Science Research Project of Guangdong Province(No.2017B030301013)and Shenzhen Science and Technology Research Grant(No.ZDSYS201707281026184).
文摘Lithium(Li)metal is one of the most promising anodes for next-generation energy storage systems.However,the Li dendrite formation and unstable solid-electrolyte interface(SEI)have hindered its further application.Lithium nitrate(LiNO3)is extensively used as an effective electrolyte additive in ether-based electrolytes to improve the stability of lithium metal.Nevertheless,it is rarely utilized in carbonate electrolytes due to its low solubility.Here,a novel gel polymer electrolyte(GPE)consisting of poly(vinylidene fluoride)(PVDF),poly(methyl methacrylate)(PMMA),poly(ethylene oxide)(PEO)with LiN03 additive is proposed to solve this issue.In this GPE,polyether-based PEO serves as a matrix for dissolving LiNO3 which can be decomposed into a fast Li-ion conductor(Li3N)in conventional carbonate electrolytes to enhance the stability and Li^+conductivity of the SEI film.As a result,dendrite formation is effectively suppressed,and a significantly improved average Coulombic efficiency(CE)of 97.2%in Li-Cu cell is achieved.By using this novel GPE coupled with Li anode and LiNi0.5Mn0.3Co0.2O2(NMC532),excellent capacity retention of 94.1%and high average CE of over 99.2%are obtained after 200 cycles at 0.5 C.This work presents fresh insight into practical modification strategies on high-voltage Li metal batteries.
基金financially supported by National Key R&D Program of China(No.2016YFB0700600)Soft Science Research Project of Guangdong Province(No.2017B030301013)。
文摘Succinonitrile(SN)based solid-state electrolytes(SSEs)have potential applications in lithium(Li)batteries due to their ease of preparation and high ionic conductivity at room temperature.Here,a novel SSE consisting of poly(vinylidene fluoride-hexafluoropropy-lene)(PVDF-HFP),poly(methyl methacrylate)(PMMA)and Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3) with SN is fabricated,where PMMA is added to serve as a polymer matrix for better wettability of SN.Due to the addition of PMMA,improved room-temperature ionic conductivity of the SSE is resulted.More importantly,better interfacial contact as well as more stable solid-state electrolyte(SEI)layer between SSE and Li anode can be also obtained.As a result,homogeneous and dendrite-free Li plating can be achieved for over 1000 h in Li symmetric cells.When coupled with LiNi_(0.5)Mn_(0.3)Co_(0.2)O_(2) cathode and Li anode,the proposed SSE delivers excellent cycling stability and rate capability in full-cells.By implementing SSEs with a polymeric wetting agent,this work provides fresh perspectives on stabilizing the interface between SSEs and Li metal anodes.
基金supported by the National Natural Science Foundation of China (Nos. 40902014 and 51472064)the Natural Scientific Research Innovation Foundation in Harbin Institute of Technology (HIT.NSRIF 2013055)
文摘A facile one-pot hydrothermal procedure for the synthesis of magnetic greigite was investigated in this work, by using FeSO4, thioacetamide, and a tiny amount of hexamethylenetetramine (HMTA) as starting materials. The HMTA molecule, which acted as a chelating agent and an oxidant, could not only tune the valence fluctuation of iron ions, but also direct the hydrothermal reaction towards the exclusive for- mation of greigite platelets with hundreds of nanometers in lateral size. In the presence of a static magnetic field during this synthesis, the greigite nano-platelets were apt to congregate to form 3D flower-like microspheres. A set of experiments suggested that the ferrous ions were at first partly oxidized by HMTA to form ferric intermediates, i.e., Fe(OH)3 and Fe2O3. Then excessive ferrous ions, along with the solid in- termediates, reacted with sulfide ions, and finally evolved into greigite, Taken into consideration that a similar process occurred in magnetotactic bacteria, our results may give a hint at the design of biomimetic synthesis strategies to produce nanomaterials, especially the magnetosome-like greigite.