Palmitoleic acid(POA)can be naturally found only in few oil seeds and has significant applications in pharmaceutical industry.Recently,the isolated oleaginous yeast Scheffersomyces segobiensis DSM 27193 was identified...Palmitoleic acid(POA)can be naturally found only in few oil seeds and has significant applications in pharmaceutical industry.Recently,the isolated oleaginous yeast Scheffersomyces segobiensis DSM 27193 was identified with high content of POA in its intracellular lipid(13.80%).In this study,process optimization focused on dissolved oxygen regulation to improve POA production was conducted.Dynamic agitation was found to do significant enhancement on POA-rich lipid production than aeration regulation.Under the best condition of 1000 r·min^(-1)of agitation and 1 vvm(airvolume/culture volume/min)of aeration,no ethanol was detected during the whole fermentation process,while a dry biomass concentration of 44.80 g·L^(-1)with 13.43 g·L^(-1)of lipid and 2.93 g·L^(-1)of POA was achieved.Transcription analysis revealed that the ethanol synthetic pathway was downregulated under the condition of high agitation,while the expression of the key enzymes responsible for lipid and POA accumulation were enhanced.展开更多
We report polarization reversal periodically controlled by the electric field in multiferroic MnWO_(4) with a pulsed field up to 52 T.The electric polarization cannot be reversed by successive opposite electric fields...We report polarization reversal periodically controlled by the electric field in multiferroic MnWO_(4) with a pulsed field up to 52 T.The electric polarization cannot be reversed by successive opposite electric fields in low magnetic fields(<14 T)at 4.2 K,whereas polarization reversal is directly achieved by two opposite electric fields under high magnetic fields(<45 T).Interestingly,the polarization curve of rising and falling fields for H∥u(magnetic easy axis)is irreversible when the magnetic field is close to 52 T.In this case,the rising and falling polarization curves can be individually reversed by the electric field,and thus require five cycles to recover to the initial condition by the order of the applied electric fields(+E,-E,-E,+E,+E).In addition,we find that ferroelectric phaseⅣcan be tuned from parallel to antiparallel in relation to ferroelectric phase AF2 by applying a magnetic field approximated to the c axis.展开更多
Halide perovskites with naturally coupled electron-ion dynamics hold greatpotential for nonvolatile memory applications. Self-rectifying memristors arepromising as they can avoid sneak currents and simplify device con...Halide perovskites with naturally coupled electron-ion dynamics hold greatpotential for nonvolatile memory applications. Self-rectifying memristors arepromising as they can avoid sneak currents and simplify device configuration.Here we report a self-rectifying memristor firstly achieved in a single perovskite(NH CINH_(3))_(3)PbI_(5) (abbreviated as (IFA)_(3)PbI_(5)), which is sandwiched byAg and ITO electrodes as the simplest cell in a crossbar array device configuration.The iodide ions of (IFA)_(3)PbI_(5) can be easily activated, of which the migrationin the bulk contributes to the resistance hysteresis and the reaction withAg at the interface contributes to the spontaneous formation of AgI. The perfectcombination of n-type AgI and p-type (IFA)_(3)PbI_(5) gives rise to the rectificationfunction like a p–n diode. Such a self-rectifying memristor exhibits therecord-low set power consumption and voltage. This work emphasizes that themultifunction of ions in perovskites can simplify the fabrication procedure,decrease the programming power, and increase the integration density offuture memory devices.展开更多
In this paper,a novel BC_(3)N_(2)monolayer has been found with a graphene-like structure using the developed particle swarm optimization algorithm in combination with ab initio calculations.The predicted structure mee...In this paper,a novel BC_(3)N_(2)monolayer has been found with a graphene-like structure using the developed particle swarm optimization algorithm in combination with ab initio calculations.The predicted structure meets the thermodynamical,dynamical,and mechanical stability requirements.Interestingly,the BC_(3)N_(2)plane shows a metallic character.Importantly,BC_(3)N_(2)has an in-plane stiffness comparable to that of graphene.We have also investigated the adsorption characteristics of CO_(2)on pristine monolayer and Mo functionalized monolayer using density functional theory.Subsequently,electronic structures of the interacting systems(CO_(2)molecule and substrates)have been preliminarily explored.The results show that Mo/BC_(3)N_(2)has a stronger adsorption capacity towards CO_(2)comparing with the pristine one,which can provide a reference for the further study of the CO_(2)reduction mechanism on the transition metal-functionalized surface as well as the new catalyst’s design.展开更多
Using the global particle-swarm optimization method and density functional theory,we predict a new stable two-dimensional layered material:MgSiP_(2)with a low-buckled honeycomb lattice.Our HSE06 calculation shows that...Using the global particle-swarm optimization method and density functional theory,we predict a new stable two-dimensional layered material:MgSiP_(2)with a low-buckled honeycomb lattice.Our HSE06 calculation shows that MgSiP_(2)is an indirect-gap semiconductor with a band-gap of 1.20 eV,closed to that of bulk silicon.More remarkably,MgSiP_(2)exhibits worthwhile anisotropy along with electron and hole carrier mobility.A ultrahigh electron mobility is even up to 1.29×10^(4)cm^(2)V^(-1)s^(-1).while the hole mobility is nearly zero along the a direction.The large difference of the mobility between electron and hole together with the suitable band-gap suggest that MgSiP_(2)may be a good candidate for solar cell or photochemical catalysis material.Furthermore,we explore MgSiP_(2)as an anode for sodium-ion batte ries.Upon Na adsorption,the semiconducting MgSiP_(2)transforms to a metallic state,ensuring good electrical conductivity.A maximum theoretical capacity of 1406 mAh/g,a small volume change(within 9.5%),a small diffusion barrier(~0.16 eV)and low average open-circuit voltages(~0.15 V)were found fo r MgSiP_(2)as an anode for sodium-ion batteries.These results are helpful to deepen the understanding of MgSiP_(2)as a nanoelectronic device and a potential anode for Na-ion batteries.展开更多
Multivariate dynamic networks indicate networks whose topology structure and vertex attributes are evolving along time.They are common in multimedia applications.Anomaly detection is one of the essential tasks in anal...Multivariate dynamic networks indicate networks whose topology structure and vertex attributes are evolving along time.They are common in multimedia applications.Anomaly detection is one of the essential tasks in analyzing these networks though it is not well addressed.In this paper,we combine a rare category detection method and visualization techniques to help users to identify and analyze anomalies in multivariate dynamic networks.We conclude features of rare categories and two types of anomalies of rare categories.Then we present a novel rare category detection method,called DIRAD,to detect rare category candidates with anomalies.We develop a prototype system called iNet,which integrates two major visualization components,including a glyph-based rare category identifier,which helps users to identify rare categories among detected substructures,a major view,which assists users to analyze and interpret the anomalies of rare categories in network topology and vertex attributes.Evaluations,including an algorithm performance evaluation,a case study,and a user study,are conducted to test the effectiveness of proposed methods.展开更多
As electrodes,two-dimensio nal materials show special advantages including the infinite planar lengths,broad electrochemical window,large surface-volume ratio,and much exposed active sites.In theory,the two-dimensiona...As electrodes,two-dimensio nal materials show special advantages including the infinite planar lengths,broad electrochemical window,large surface-volume ratio,and much exposed active sites.In theory,the two-dimensional materials consist of the elements with high electronegativity may absorb more Na atoms,resulting in a high battery storage capacity.Based on the above idea,we selected the two dimensional metallic PS2 with 1 T-Type structure as an anode material,and explored its potential applications as an electrode material for Na-ion battery through first-principle calculations.As we expected,when two dimensional PS2 is used as an anode in Na-ion battery,it can adsorb maximum three layers of sodium atoms on both sides of the monolayer,resulting in a maximum theoretical capacity of 1692 mAh/g.Furthermore,it also possesses a rather small sodium diffusion barrier of 0.17 eV,a low average open-circuit voltage of 0.18 V,and a relatively small lattice changes within 13% during the intercalation of Na.These results suggested that the two dimensional PS2 is a potentially excellent Na-ion battery anode.Our idea of designing two-dimensional anode materials with high storage capacity may provide some references for designing the next generation anode materials of metal-ion batteries.展开更多
Background:Hyperchloremia is associated with increased mortality in critically ill patients.The objective of this study was to investigate the association between increased chloride levels and mortality outcomes in in...Background:Hyperchloremia is associated with increased mortality in critically ill patients.The objective of this study was to investigate the association between increased chloride levels and mortality outcomes in intracerebral hemorrhage(ICH)patients admitted to the intensive care unit(ICU).Methods:We performed a retrospective study of all patients diagnosed with ICH and included in the Medical Information Mart for Intensive Care(MIMIC-III)from 2001 to 2012.Inclusion criteria were the first diagnosis of ICH,ICU length of stay(LOS)over 72 h,and not receiving hypertonic saline treatment.Serum chloride perturbation within 72 h of admission was evaluated as a predictor of outcomes.The increase in chloride from baseline was dichotomized based on an increase in chloride in 72 h(≤5 mmol/L or>5 mmol/L).The primary outcome was 90-day mortality.Results:A total of 376 patients(54.5%male,median age 70 years,interquartile range:58–79 years)were included.The overall 90-day mortality was 32.2%(n=121),in-hospital mortality was 25.8%(n=97),and Day 2 acute kidney injury(AKI)occurred in 29.0%(n=109)of patients.The prevalence of hyperchloremia on admission,during the first 72 h,and an increase in chloride(>5 mmol/L)were 8.8%,39.4%,and 42.8%,respectively.After adjusting for confounders,the hazard ratio of increase in chloride(>5 mmol/L)was 1.66(95%confidence interval:1.05–2.64,P=0.031).An increase in chloride(>5 mmol/L)was associated with a higher odds ratio for 90-day mortality in both the AKI and non-AKI groups.Conclusions:An increase in chloride from baseline is common in adult patients with ICH admitted to ICU.The increase is significantly associated with elevated mortality.These results support the significance of diligently monitoring chloride levels in these patients.展开更多
Electroreduction of carbon dioxide(CO_(2))into valuable chemicals and fuels is a promising strategy to mitigate energy and environmental problems.However,the poor selectivity and inadequate electrochemical stability p...Electroreduction of carbon dioxide(CO_(2))into valuable chemicals and fuels is a promising strategy to mitigate energy and environmental problems.However,the poor selectivity and inadequate electrochemical stability prevent practical applications.In this work,we prepared ultrasmall copper(Cu)nanoparticles by using tannic acid as a complexing agent and stablizer.The ultrasmall Cu nanoparticles(3.4 nm)exhibited outstanding performance for CO_(2)electroreduction to CH_(4).The Faradaic efficiency of CH_(4)could reach up to 68%at-1.2 V versus reversible hydrogen electrode(RHE),with high current density of 475 mA·cm^(-2).The ultrasmall Cu nanoparticles could enhance the CO adsorption and H2O activation,resulting in the high selectivity of CH_(4).展开更多
基金supported by the National Key Research & Development Program of China (2021YFC2101500, 2018YFA0902200)National Natural Science Foundation of China (22008115, 21978130)+4 种基金Jiangsu Province Natural Science Foundation for Youths (SBK2020044721)Jiangsu Provincial Agricultural Science and Technology Independent Innovation Fund Project (CX(21)3120)Jiangsu Planned Projects for Postdoctoral Research Funds (2021K085A)China Postdoctoral Science Foundation (2020M671467)Postdoctoral Research Funding Program of Jiangsu Province (2021K085A)
文摘Palmitoleic acid(POA)can be naturally found only in few oil seeds and has significant applications in pharmaceutical industry.Recently,the isolated oleaginous yeast Scheffersomyces segobiensis DSM 27193 was identified with high content of POA in its intracellular lipid(13.80%).In this study,process optimization focused on dissolved oxygen regulation to improve POA production was conducted.Dynamic agitation was found to do significant enhancement on POA-rich lipid production than aeration regulation.Under the best condition of 1000 r·min^(-1)of agitation and 1 vvm(airvolume/culture volume/min)of aeration,no ethanol was detected during the whole fermentation process,while a dry biomass concentration of 44.80 g·L^(-1)with 13.43 g·L^(-1)of lipid and 2.93 g·L^(-1)of POA was achieved.Transcription analysis revealed that the ethanol synthetic pathway was downregulated under the condition of high agitation,while the expression of the key enzymes responsible for lipid and POA accumulation were enhanced.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.12074135,12104388,and 52272219)Nanyang Normal University,the Natural Science Foundation of Henan Province (Grant Nos.222300420255 and 232300421220)the Key Scientific and Technological Projiect of Technology Depeartment of Henan Province of China (Grant Nos.222102230105 and 212102210448)。
文摘We report polarization reversal periodically controlled by the electric field in multiferroic MnWO_(4) with a pulsed field up to 52 T.The electric polarization cannot be reversed by successive opposite electric fields in low magnetic fields(<14 T)at 4.2 K,whereas polarization reversal is directly achieved by two opposite electric fields under high magnetic fields(<45 T).Interestingly,the polarization curve of rising and falling fields for H∥u(magnetic easy axis)is irreversible when the magnetic field is close to 52 T.In this case,the rising and falling polarization curves can be individually reversed by the electric field,and thus require five cycles to recover to the initial condition by the order of the applied electric fields(+E,-E,-E,+E,+E).In addition,we find that ferroelectric phaseⅣcan be tuned from parallel to antiparallel in relation to ferroelectric phase AF2 by applying a magnetic field approximated to the c axis.
基金National Key Research and Development Program of China,Grant/Award Numbers:2020YFA0308900,2022YFB3602801National Natural Science Foundation of China,Grant/Award Numbers:52373290,62288102。
文摘Halide perovskites with naturally coupled electron-ion dynamics hold greatpotential for nonvolatile memory applications. Self-rectifying memristors arepromising as they can avoid sneak currents and simplify device configuration.Here we report a self-rectifying memristor firstly achieved in a single perovskite(NH CINH_(3))_(3)PbI_(5) (abbreviated as (IFA)_(3)PbI_(5)), which is sandwiched byAg and ITO electrodes as the simplest cell in a crossbar array device configuration.The iodide ions of (IFA)_(3)PbI_(5) can be easily activated, of which the migrationin the bulk contributes to the resistance hysteresis and the reaction withAg at the interface contributes to the spontaneous formation of AgI. The perfectcombination of n-type AgI and p-type (IFA)_(3)PbI_(5) gives rise to the rectificationfunction like a p–n diode. Such a self-rectifying memristor exhibits therecord-low set power consumption and voltage. This work emphasizes that themultifunction of ions in perovskites can simplify the fabrication procedure,decrease the programming power, and increase the integration density offuture memory devices.
基金supported by the National Natural Science Foundation of China(Nos.21603109,U1404216,U1904179,U1404608)the Special Fund of Tianshui Normal University,China(Grant No.CXJ2020-08)+1 种基金the Key Science Fund of Educational Department of Henan Province of China(Nos.19A140013,20B140010)Shaanxi Provincial Education Department Serves Local Scientific Research Program(Nos.19JC020,20JK0676)。
文摘In this paper,a novel BC_(3)N_(2)monolayer has been found with a graphene-like structure using the developed particle swarm optimization algorithm in combination with ab initio calculations.The predicted structure meets the thermodynamical,dynamical,and mechanical stability requirements.Interestingly,the BC_(3)N_(2)plane shows a metallic character.Importantly,BC_(3)N_(2)has an in-plane stiffness comparable to that of graphene.We have also investigated the adsorption characteristics of CO_(2)on pristine monolayer and Mo functionalized monolayer using density functional theory.Subsequently,electronic structures of the interacting systems(CO_(2)molecule and substrates)have been preliminarily explored.The results show that Mo/BC_(3)N_(2)has a stronger adsorption capacity towards CO_(2)comparing with the pristine one,which can provide a reference for the further study of the CO_(2)reduction mechanism on the transition metal-functionalized surface as well as the new catalyst’s design.
基金supported by Henan Joint Funds of the National Natural Science Foundation of China(Nos.U1904179,U1404608 and U1404216)the National Natural Science Foundation of China(No.21603109)the Key Science Fund of Educational Department of Henan Province of China(No.20B140010)。
文摘Using the global particle-swarm optimization method and density functional theory,we predict a new stable two-dimensional layered material:MgSiP_(2)with a low-buckled honeycomb lattice.Our HSE06 calculation shows that MgSiP_(2)is an indirect-gap semiconductor with a band-gap of 1.20 eV,closed to that of bulk silicon.More remarkably,MgSiP_(2)exhibits worthwhile anisotropy along with electron and hole carrier mobility.A ultrahigh electron mobility is even up to 1.29×10^(4)cm^(2)V^(-1)s^(-1).while the hole mobility is nearly zero along the a direction.The large difference of the mobility between electron and hole together with the suitable band-gap suggest that MgSiP_(2)may be a good candidate for solar cell or photochemical catalysis material.Furthermore,we explore MgSiP_(2)as an anode for sodium-ion batte ries.Upon Na adsorption,the semiconducting MgSiP_(2)transforms to a metallic state,ensuring good electrical conductivity.A maximum theoretical capacity of 1406 mAh/g,a small volume change(within 9.5%),a small diffusion barrier(~0.16 eV)and low average open-circuit voltages(~0.15 V)were found fo r MgSiP_(2)as an anode for sodium-ion batteries.These results are helpful to deepen the understanding of MgSiP_(2)as a nanoelectronic device and a potential anode for Na-ion batteries.
基金This work was supported by National Key Research and Development Program(2018YFB0904503)the National Natural Science Foundation of China(Grant Nos.61772456,U1866602,61761136020,U1736109).
文摘Multivariate dynamic networks indicate networks whose topology structure and vertex attributes are evolving along time.They are common in multimedia applications.Anomaly detection is one of the essential tasks in analyzing these networks though it is not well addressed.In this paper,we combine a rare category detection method and visualization techniques to help users to identify and analyze anomalies in multivariate dynamic networks.We conclude features of rare categories and two types of anomalies of rare categories.Then we present a novel rare category detection method,called DIRAD,to detect rare category candidates with anomalies.We develop a prototype system called iNet,which integrates two major visualization components,including a glyph-based rare category identifier,which helps users to identify rare categories among detected substructures,a major view,which assists users to analyze and interpret the anomalies of rare categories in network topology and vertex attributes.Evaluations,including an algorithm performance evaluation,a case study,and a user study,are conducted to test the effectiveness of proposed methods.
基金supported by the Henan Joint Funds of the National Natural Science Foundation of China(Nos.U1904179 and U1404608,21603109,U1404216)the National Natural Science Foundation of China(Nos.21603109,51501093)the Key Science Fund of Educational Department of Henan Province of China(No.20B140010)。
文摘As electrodes,two-dimensio nal materials show special advantages including the infinite planar lengths,broad electrochemical window,large surface-volume ratio,and much exposed active sites.In theory,the two-dimensional materials consist of the elements with high electronegativity may absorb more Na atoms,resulting in a high battery storage capacity.Based on the above idea,we selected the two dimensional metallic PS2 with 1 T-Type structure as an anode material,and explored its potential applications as an electrode material for Na-ion battery through first-principle calculations.As we expected,when two dimensional PS2 is used as an anode in Na-ion battery,it can adsorb maximum three layers of sodium atoms on both sides of the monolayer,resulting in a maximum theoretical capacity of 1692 mAh/g.Furthermore,it also possesses a rather small sodium diffusion barrier of 0.17 eV,a low average open-circuit voltage of 0.18 V,and a relatively small lattice changes within 13% during the intercalation of Na.These results suggested that the two dimensional PS2 is a potentially excellent Na-ion battery anode.Our idea of designing two-dimensional anode materials with high storage capacity may provide some references for designing the next generation anode materials of metal-ion batteries.
基金supported by the Foundation of Beijing Tongren Hospital,Capital Medical University(No.2021-YJJ-ZZL-026).
文摘Background:Hyperchloremia is associated with increased mortality in critically ill patients.The objective of this study was to investigate the association between increased chloride levels and mortality outcomes in intracerebral hemorrhage(ICH)patients admitted to the intensive care unit(ICU).Methods:We performed a retrospective study of all patients diagnosed with ICH and included in the Medical Information Mart for Intensive Care(MIMIC-III)from 2001 to 2012.Inclusion criteria were the first diagnosis of ICH,ICU length of stay(LOS)over 72 h,and not receiving hypertonic saline treatment.Serum chloride perturbation within 72 h of admission was evaluated as a predictor of outcomes.The increase in chloride from baseline was dichotomized based on an increase in chloride in 72 h(≤5 mmol/L or>5 mmol/L).The primary outcome was 90-day mortality.Results:A total of 376 patients(54.5%male,median age 70 years,interquartile range:58–79 years)were included.The overall 90-day mortality was 32.2%(n=121),in-hospital mortality was 25.8%(n=97),and Day 2 acute kidney injury(AKI)occurred in 29.0%(n=109)of patients.The prevalence of hyperchloremia on admission,during the first 72 h,and an increase in chloride(>5 mmol/L)were 8.8%,39.4%,and 42.8%,respectively.After adjusting for confounders,the hazard ratio of increase in chloride(>5 mmol/L)was 1.66(95%confidence interval:1.05–2.64,P=0.031).An increase in chloride(>5 mmol/L)was associated with a higher odds ratio for 90-day mortality in both the AKI and non-AKI groups.Conclusions:An increase in chloride from baseline is common in adult patients with ICH admitted to ICU.The increase is significantly associated with elevated mortality.These results support the significance of diligently monitoring chloride levels in these patients.
基金the National Key Research and Development Program of China(grant no.2023YFA1507901)National Natural Science Foundation of China(grant nos.22003070,22293015,and 22121002).
文摘Electroreduction of carbon dioxide(CO_(2))into valuable chemicals and fuels is a promising strategy to mitigate energy and environmental problems.However,the poor selectivity and inadequate electrochemical stability prevent practical applications.In this work,we prepared ultrasmall copper(Cu)nanoparticles by using tannic acid as a complexing agent and stablizer.The ultrasmall Cu nanoparticles(3.4 nm)exhibited outstanding performance for CO_(2)electroreduction to CH_(4).The Faradaic efficiency of CH_(4)could reach up to 68%at-1.2 V versus reversible hydrogen electrode(RHE),with high current density of 475 mA·cm^(-2).The ultrasmall Cu nanoparticles could enhance the CO adsorption and H2O activation,resulting in the high selectivity of CH_(4).
