Phosphorus(P)is essential for living plants,and P deficiency is one of the key factors limiting the yield in rapeseed production worldwide.As the most important organ for plants,root morphology traits(RMTs)play a key ...Phosphorus(P)is essential for living plants,and P deficiency is one of the key factors limiting the yield in rapeseed production worldwide.As the most important organ for plants,root morphology traits(RMTs)play a key role in P absorption.To investigate the genetic variability of RMT under low P availability,we dissected the genetic structure of RMTs by genome-wide association studies(GWAS),linkage mapping and candidate gene association studies(CGAS).A total of 52 suggestive loci were associated with RMTs under P stress conditions in 405 oilseed rape accessions.The purple acid phosphatase gene BnPAP17 was found to control the lateral root number(LRN)and root dry weight(RDW)under low P stress.The expression of BnPAP17 was increased in shoot tissue in P-efficient cultivars compared to root tissue and P-inefficient cultivars in response to low P stress.Moreover,the haplotype of BnPAP17^(Hap3)was detected for the selective breeding of P efficiency in oilseed rape.Over-expression of the BnPAP17^(Hap3)could promote the shoot and root growth with enhanced tolerance to low P stress and organic phosphorus(Po)utilization in oilseed rape.Collectively,these findings increase our understanding of the mechanisms underlying BnPAP17-mediated low P stress tolerance in oilseed rape.展开更多
Graphene-based thermally conductive composites have been proposed as effective thermal management materials for cooling high-power electronic devices.However,when flexible graphene nanosheets are assembled into macros...Graphene-based thermally conductive composites have been proposed as effective thermal management materials for cooling high-power electronic devices.However,when flexible graphene nanosheets are assembled into macroscopic thermally conductive composites,capillary forces induce shrinkage of graphene nanosheets to form wrinkles during solution-based spontaneous drying,which greatly reduces the thermal conductivity of the composites.Herein,graphene nanosheets/aramid nanofiber(GNS/ANF)composite films with high thermal conductivity were prepared by in-plane stretching of GNS/ANF composite hydrogel networks with hydrogen bonds andπ-πinteractions.The in-plane mechanical stretching eliminates graphene nanosheets wrinkles by suppressing inward shrinkage due to capillary forces during drying and achieves a high in-plane orientation of graphene nanosheets,thereby creating a fast in-plane heat transfer channel.The composite films(GNS/ANF-60 wt%)with eliminated graphene nanosheets wrinkles showed a significant increase in thermal conductivity(146 W m^(−1)K^(−1))and tensile strength(207 MPa).The combination of these excellent properties enables the GNS/ANF composite films to be effectively used for cooling flexible LED chips and smartphones,showing promising applications in the thermal management of high-power electronic devices.展开更多
Inactive elemental doping is commonly used to improve the structural stability of high-voltage layered transition-metal oxide cathodes.However,the one-step co-doping strategy usually results in small grain size since ...Inactive elemental doping is commonly used to improve the structural stability of high-voltage layered transition-metal oxide cathodes.However,the one-step co-doping strategy usually results in small grain size since the low diffusivity ions such as Ti^(4+)will be concentrated on grain boundaries,which hinders the grain growth.In order to synthesize large single-crystal layered oxide cathodes,considering the different diffusivities of different dopant ions,we propose a simple two-step multi-element co-doping strategy to fabricate core–shell structured LiCoO_(2)(CS-LCO).In the current work,the high-diffusivity Al^(3+)/Mg^(2+)ions occupy the core of single-crystal grain while the low diffusivity Ti^(4+)ions enrich the shell layer.The Ti^(4+)-enriched shell layer(~12 nm)with Co/Ti substitution and stronger Ti–O bond gives rise to less oxygen ligand holes.In-situ XRD demonstrates the constrained contraction of c-axis lattice parameter and mitigated structural distortion.Under a high upper cut-off voltage of 4.6 V,the single-crystal CS-LCO maintains a reversible capacity of 159.8 mAh g^(−1)with a good retention of~89%after 300 cycles,and reaches a high specific capacity of 163.8 mAh g^(−1)at 5C.The proposed strategy can be extended to other pairs of low-(Zr^(4+),Ta^(5+),and W6+,etc.)and high-diffusivity cations(Zn^(2+),Ni^(2+),and Fe^(3+),etc.)for rational design of advanced layered oxide core–shell structured cathodes for lithium-ion batteries.展开更多
Hydroxyl-terminated polybutadiene/toluene diisocyanate(HTPB/TDI)system is widely used in composite solid propellants.The migrations of plasticizers and water molecules from solid propellants and surrounding environmen...Hydroxyl-terminated polybutadiene/toluene diisocyanate(HTPB/TDI)system is widely used in composite solid propellants.The migrations of plasticizers and water molecules from solid propellants and surrounding environment to the inhibitor have always been the important issues.This study focuses on the preparation,characterization and anti-migration behavior of graphene oxide(GO)/HTPB nanocomposite liner.The GO/HTPB(GH)composite liners affect the migration of small molecules through a tighter cross-linked structure and weakening function of small molecule adsorption.The anti-migration performance of the liner at different temperatures was analyzed,and the influence of the added amount of GO on the anti-migration performance and adhesion performance was also systematically studied.The overall performance of the liner is optimized when the amount of GO filler is 0.3 wt%.After adding 0.3 wt%GO,the concentration of dioctyl sebacate(DOS)migrated into the liner is decreased by 23.28%,and the concentration of water molecules is decreased by 51.89%,indicating that the introduction of GO can significantly improve the anti-migration performance of the liner.In addition,the bond strength is greatly increased from 0.25 MPa to 0.95 MPa,which meets the application requirements of the current propellant system.This research provides an important way for the preparation of structure-function synergistic anti-migration composite liners.展开更多
BACKGROUND Chronic heart failure(CHF)is a serious and prevalent condition characterized by impaired cardiac function and inflammation.Standard therapy for CHF has limitations,prompting the exploration of alternative t...BACKGROUND Chronic heart failure(CHF)is a serious and prevalent condition characterized by impaired cardiac function and inflammation.Standard therapy for CHF has limitations,prompting the exploration of alternative treatments.Recombinant human brain natriuretic peptide(BNP)has emerged as a potential therapy,with evidence suggesting that it can improve cardiac function and reduce inflammation in patients with CHF.However,further research is required to determine the efficacy and safety of lyophilized recombinant human BNP in CHF patients and its impact on microinflammatory status.This study aimed to investigate the effects of lyophilized recombinant human BNP therapy on CHF patients’cardiac function and microinflammatory status.AIM To investigate the effects of freeze-dried recombinant human BNP therapy on cardiac function and microinflammatory status in patients with CHF.METHODS In total,102 CHF patients admitted to our hospital from January 2021 to January 2022 were randomly assigned to control and observation groups(n=51 patients/group).The control patients were treated with standard HF therapy for 3 d,whereas the observational patients were injected with the recombinant human BNP for 3 d.Clinical efficacy,inflammatory factor levels,myocardial damage,cardiac function before and after the treatment,and adverse reactions during treatment were compared between the two groups.RESULTS The overall clinical efficacy was higher in the observation group than in the control group.Compared with baseline,serum hypersensitive C-reactive protein,N-terminal proBNP,and troponin I level,and physical,emotional,social,and economic scores were lower in both groups after treatment,with greater reductions in levels and scores noted in the observation group than in the control group.The overall incidence of adverse reactions in the observation group was not significantly different compared with that in the control group(P>0.05).CONCLUSION Freeze-dried recombinant human BNP therapy can improve heart function and enhance microinflammatory status,thereby improving overall quality of life without any obvious side effects.This therapy is safe and reliable.展开更多
The vehicular sensor network (VSN) is an important part of intelligent transportation, which is used for real-timedetection and operation control of vehicles and real-time transmission of data and information. In the ...The vehicular sensor network (VSN) is an important part of intelligent transportation, which is used for real-timedetection and operation control of vehicles and real-time transmission of data and information. In the environmentofVSN, massive private data generated by vehicles are transmitted in open channels and used by other vehicle users,so it is crucial to maintain high transmission efficiency and high confidentiality of data. To deal with this problem, inthis paper, we propose a heterogeneous fault-tolerant aggregate signcryption scheme with an equality test (HFTASET).The scheme combines fault-tolerant and aggregate signcryption,whichnot onlymakes up for the deficiency oflow security of aggregate signature, but alsomakes up for the deficiency that aggregate signcryption cannot tolerateinvalid signature. The scheme supports one verification pass when all signcryptions are valid, and it supportsunbounded aggregation when the total number of signcryptions grows dynamically. In addition, this schemesupports heterogeneous equality test, and realizes the access control of private data in different cryptographicenvironments, so as to achieve flexibility in the application of our scheme and realize the function of quick searchof plaintext or ciphertext. Then, the security of HFTAS-ET is demonstrated by strict theoretical analysis. Finally, weconduct strict and standardized experimental operation and performance evaluation, which shows that the schemehas better performance.展开更多
BACKGROUND The multidisciplinary team(MDT)has been carried out in many large hospitals now.However,given the costs of time and money and with little strong evidence of MDT effectiveness being reported,critiques of MDT...BACKGROUND The multidisciplinary team(MDT)has been carried out in many large hospitals now.However,given the costs of time and money and with little strong evidence of MDT effectiveness being reported,critiques of MDTs persist.AIM To evaluate the effects of MDTs on patients with synchronous colorectal liver metastases and share our opinion on management of synchronous colorectal liver metastases.METHODS In this study we collected clinical data of patients with synchronous colorectal liver metastases from February 2014 to February 2017 in the Chinese People’s Liberation Army General Hospital and subsequently divided them into an MDT+group and an MDT-group.In total,93 patients in MDT+group and 169 patients in MDT-group were included totally.RESULTS Statistical increases in the rate of chest computed tomography examination(P=0.001),abdomen magnetic resonance imaging examination(P=0.000),and preoperative image staging(P=0.0000)were observed in patients in MDT+group.Additionally,the proportion of patients receiving chemotherapy(P=0.019)and curative resection(P=0.042)was also higher in MDT+group.Multivariable analysis showed that the population of patients assessed by MDT meetings had higher 1-year[hazard ratio(HR)=0.608,95%confidence interval(CI):0.398-0.931,P=0.022]and 5-year(HR=0.694,95%CI:0.515-0.937,P=0.017)overall survival.CONCLUSION These results proved that MDT management did bring patients with synchronous colorectal liver metastases more opportunities for comprehensive examination and treatment,resulting in better outcomes.展开更多
During the drilling process,stick-slip vibration of the drill string is mainly caused by the nonlinear friction gen-erated by the contact between the drill bit and the rock.To eliminate the fatigue wear of downhole dr...During the drilling process,stick-slip vibration of the drill string is mainly caused by the nonlinear friction gen-erated by the contact between the drill bit and the rock.To eliminate the fatigue wear of downhole drilling tools caused by stick-slip vibrations,the Fractional-Order Proportional-Integral-Derivative(FOPID)controller is used to suppress stick-slip vibrations in the drill string.Although the FOPID controller can effectively suppress the drill string stick-slip vibration,its structure isflexible and parameter setting is complicated,so it needs to use the cor-responding machine learning algorithm for parameter optimization.Based on the principle of torsional vibration,a simplified model of multi-degree-of-freedom drill string is established and its block diagram is designed.The continuous nonlinear friction generated by cutting rock is described by the LuGre friction model.The adaptive learning strategy of genetic algorithm(GA),particle swarm optimization(PSO)and particle swarm optimization improved(IPSO)by arithmetic optimization(AOA)is used to optimize and adjust the controller parameters,and the drill string stick-slip vibration is suppressed to the greatest extent.The results show that:When slight drill string stick-slip vibration occurs,the FOPID controller optimized by machine learning algorithm has a good effect on suppressing drill string stick-slip vibration.However,the FOPID controller cannot get the drill string system which has fallen into serious stick-slip vibration(stuck pipe)out of trouble,and the machine learning algorithm is required to mark a large amount of data on adjacent Wells to train the model.Set a reasonable range of drilling parameters(weight on bit/drive torque)in advance to avoid severe stick-slip vibration(stuck pipe)in the drill string system.展开更多
With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux ex...With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux extraction and ultrasound-assisted extraction,and the effects of different extraction methods the contents of total flavonoids in P.edulis from different areas were compared.The results showed that the best extraction time for P.edulis in Yunnan Province was 20 min,and that for Guangdong and Guangxi Zhuang Autonomous Region was 30 min.The yield of total flavonoids from P.edulis extracted by the condensation reflux extraction method was relatively better.The content of total flavonoids in P.edulis in Yunnan was the highest with an average content of 0.2557%,while the average content of total flavonoids in P.edulis in Guangdong was the lowest with an average content of 0.2108%.展开更多
Background:Hepatic fibrosis is a common chronic liver disease in clinic,the purpose of our study is to explore potential biomarkers to provide a theoretical basis for the treatment of liver fibrosis with pirfenidone.M...Background:Hepatic fibrosis is a common chronic liver disease in clinic,the purpose of our study is to explore potential biomarkers to provide a theoretical basis for the treatment of liver fibrosis with pirfenidone.Methods:We downloaded a gene-sequencing dataset and a single-cell dataset from the GEO database and pirfenidone target genes from three different databases.First,we performed GO,KEGG,and DO analysis on pirfenidone target genes.Then,we grouped the liver tissue sequencing data(GSE162694)in the sequencing data set(N-F0 group and F1-F4 group)and performed gene expression differential analysis on these two groups,weighted gene co-expression network analysis and gene Enrichment analysis.Finally,we intersected the significantly upregulated genes in the F1-F4 group with the pirfenidone target genes and performed PPI network analysis.In order to further explore the expression of both pirfenidone drug target genes and liver fibrosis disease genes(PDLFG)in different immune cells of liver tissue,we used the CD45+cell data in the GSE136103 data set for further analysis.Results:A subnetwork consisting of CDC42,HNF4A,BHLHE40,CCDC71L,NR1H3,TNF,MGLL,GPT,SCD and PLIN1 was screened out,and by analysis,we finally identified the SCD as PDLFG.In single-cell sequencing analysis,we found that SCD was highly expressed in M2-polarized macrophages.Conclusion:SCD may be an important target protein to inhibit the progression of liver fibrosis.展开更多
Tea polyphenols(TP)is a class of polyhydroxy compounds isolated from tea.Modern biological and medical studies have shown that TP has many pharmacological activities,such as anti-inflammatory,anti-virus,anti-oxidation...Tea polyphenols(TP)is a class of polyhydroxy compounds isolated from tea.Modern biological and medical studies have shown that TP has many pharmacological activities,such as anti-inflammatory,anti-virus,anti-oxidation,anti-tumor and anti-radiation.Furthermore,these substances can be used as a potential drug component to positively guide the occurrence and development of certain diseases.Furthermore,because of the activities of TP,such as anti-oxidation and anti-bacteria,it can be applied in food preservation,color preservation,deodorization,and treatment of food processing by-products.Based on the research progress of TP in recent years,this paper summarizes the pharmacological activities of TP and expounds on its application potential in the field of food.In order to provide a theoretical reference for the research,development and utilization of TP.展开更多
该文针对多源时变干扰影响的双三相永磁同步电机系统,研究其基波平面内的调速控制问题和谐波平面内的谐波电流抑制问题。首先,在基波平面采用非串级控制结构,通过构造广义比例积分观测器(generalized proportional integral observer,GP...该文针对多源时变干扰影响的双三相永磁同步电机系统,研究其基波平面内的调速控制问题和谐波平面内的谐波电流抑制问题。首先,在基波平面采用非串级控制结构,通过构造广义比例积分观测器(generalized proportional integral observer,GPIO)估计转速环的多源快变干扰;然后,针对q轴电流的过流保护问题,在传统比例微分反馈控制器的基础上利用障碍函数设计思想,结合干扰估计信息,得到基于GPIO的电流约束复合控制器;其次,在谐波平面,通过设计2个GPIO精准估计电流环的多源快变干扰,并与比例反馈控制器结合形成复合控制器来抑制2个电流环中的谐波电流。最后,给出严谨的稳定性分析,并通过对比实验验证所提方法的有效性。展开更多
Deep-sea sediment disturbance may occur when collecting polymetallic nodules,resulting in the creation of plumes that could have a negative impact on the ecological environment.This study aims to investigate the poten...Deep-sea sediment disturbance may occur when collecting polymetallic nodules,resulting in the creation of plumes that could have a negative impact on the ecological environment.This study aims to investigate the potential solution of using polyaluminum chloride(PAC)in the water jet.The effects of PAC are examined through a self-designed simulation system for deep-sea polymetallic nodule collection and sediment samples from a potential deep-sea mining area.The experimental results showed that the optimal PAC dose was found to be 0.75 g/L.Compared with the test conditions without the addition of PAC,the presence of PAC leads to a reduction in volume,lower characteristic turbidity,smaller diffusion velocity,and shorter settling time of the plume.This indicates that PAC inhibits the entire development process of the plume.The addition of PAC leads to the flocculation of mm-sized particles,resulting in the formation of cm-sized flocs.The flocculation of particles decreases the rate of erosion on the seabed by around 30%.This reduction in erosion helps to decrease the formation of plumes.Additionally,when the size of suspended particles increases,it reduces the scale at which they diffuse.Furthermore,the settling velocity of flocs(around 10^(-2) m/s)is much higher that of compared to sediment particles(around 10^(-5) m/s),which effectively reduces the amount of time the plume remains in suspension.展开更多
Surface-supported isolated atoms in single-atom catalysts(SACs)grant maximum utilization of metals in heterogeneous catalysis.Herein,we report a feasible pyrolysis strategy to synthesize Pd single atoms by thermally m...Surface-supported isolated atoms in single-atom catalysts(SACs)grant maximum utilization of metals in heterogeneous catalysis.Herein,we report a feasible pyrolysis strategy to synthesize Pd single atoms by thermally melting Pd nanoparticles on an oxygen-vacancy-rich tungsten-oxide matrix at reduction atmosphere.Near ambient pressure X-ray photoelectron spectroscopy was used to monitor the formation of zero-valence Pd single atoms and the increased metallic feature of WO_(3-x)substrate.Accordingly,the as-obtained zero-valence Pd single-atom catalyst exhibits a markedly boosted HER activity with a low overpotential(η_(10)=70 mV)at the current density of 10 mA/cm2and a small Tafel slope(b=68 mV/dec),nearly 150 mV and a 3,0-fold enhancement than those of Pd nanoparticles(η_(10)=220 mV,b=133 mV/dec)under the same conditions.In addition,quasi in situ XPS results suggest the hydrogen spillover effect is more likely to occur on Pd single atoms during the electrochemical process.Our work may pave an interesting route for the rational design of highly-efficient single-atom catalysts,and the elucidation of corresponding enhanced reaction mechanisms by the utilization of advanced characterization techniques.展开更多
Amidst the swift advancement of new power systems and electric vehicles,inverter-fed machines have progressively materialized as a pivotal apparatus for efficient energy conversion.Stator winding turn insulation failu...Amidst the swift advancement of new power systems and electric vehicles,inverter-fed machines have progressively materialized as a pivotal apparatus for efficient energy conversion.Stator winding turn insulation failure is the root cause of inverter-fed machine breakdown.The online monitoring of turn insulation health can detect potential safety risks promptly,but faces the challenge of weak characteristics of turn insulation degradation.This study proposes an innovative method to evaluate the turn insulation state of inverter-fed machines by utilizing the fractional Fourier transform with a Mel filter(FrFT-Mel).First,the sensitivity of the high-frequency(HF)switching oscillation current to variations in turn insulation was analyzed within the fractional domain.Subsequently,an improved Mel filter is introduced,and its structure and parameters are specifically designed based on the features intrinsic to the common-mode impedance resonance point of the electrical machine.Finally,an evaluation index was proposed for the turn insulation state of inverter-fed machines.Experimental results on a 3kW permanent magnet synchronous machine(PMSM)demonstrate that the proposed FrFT-Mel method significantly enhances the sensitivity of turn insulation state perception by approximately five times,compared to the traditional Fourier transform method.展开更多
With the continuous advancement in topology optimization and additive manufacturing(AM)technology,the capability to fabricate functionally graded materials and intricate cellular structures with spatially varying micr...With the continuous advancement in topology optimization and additive manufacturing(AM)technology,the capability to fabricate functionally graded materials and intricate cellular structures with spatially varying microstructures has grown significantly.However,a critical challenge is encountered in the design of these structures–the absence of robust interface connections between adjacent microstructures,potentially resulting in diminished efficiency or macroscopic failure.A Hybrid Level Set Method(HLSM)is proposed,specifically designed to enhance connectivity among non-uniform microstructures,contributing to the design of functionally graded cellular structures.The HLSM introduces a pioneering algorithm for effectively blending heterogeneous microstructure interfaces.Initially,an interpolation algorithm is presented to construct transition microstructures seamlessly connected on both sides.Subsequently,the algorithm enables the morphing of non-uniform unit cells to seamlessly adapt to interconnected adjacent microstructures.The method,seamlessly integrated into a multi-scale topology optimization framework using the level set method,exhibits its efficacy through numerical examples,showcasing its prowess in optimizing 2D and 3D functionally graded materials(FGM)and multi-scale topology optimization.In essence,the pressing issue of interface connections in complex structure design is not only addressed but also a robust methodology is introduced,substantiated by numerical evidence,advancing optimization capabilities in the realm of functionally graded materials and cellular structures.展开更多
基金financially supported by the National Natural Science Foundation of China(32201868 and 32001575)。
文摘Phosphorus(P)is essential for living plants,and P deficiency is one of the key factors limiting the yield in rapeseed production worldwide.As the most important organ for plants,root morphology traits(RMTs)play a key role in P absorption.To investigate the genetic variability of RMT under low P availability,we dissected the genetic structure of RMTs by genome-wide association studies(GWAS),linkage mapping and candidate gene association studies(CGAS).A total of 52 suggestive loci were associated with RMTs under P stress conditions in 405 oilseed rape accessions.The purple acid phosphatase gene BnPAP17 was found to control the lateral root number(LRN)and root dry weight(RDW)under low P stress.The expression of BnPAP17 was increased in shoot tissue in P-efficient cultivars compared to root tissue and P-inefficient cultivars in response to low P stress.Moreover,the haplotype of BnPAP17^(Hap3)was detected for the selective breeding of P efficiency in oilseed rape.Over-expression of the BnPAP17^(Hap3)could promote the shoot and root growth with enhanced tolerance to low P stress and organic phosphorus(Po)utilization in oilseed rape.Collectively,these findings increase our understanding of the mechanisms underlying BnPAP17-mediated low P stress tolerance in oilseed rape.
基金the National Natural Science Foundation of China(No.51972162).
文摘Graphene-based thermally conductive composites have been proposed as effective thermal management materials for cooling high-power electronic devices.However,when flexible graphene nanosheets are assembled into macroscopic thermally conductive composites,capillary forces induce shrinkage of graphene nanosheets to form wrinkles during solution-based spontaneous drying,which greatly reduces the thermal conductivity of the composites.Herein,graphene nanosheets/aramid nanofiber(GNS/ANF)composite films with high thermal conductivity were prepared by in-plane stretching of GNS/ANF composite hydrogel networks with hydrogen bonds andπ-πinteractions.The in-plane mechanical stretching eliminates graphene nanosheets wrinkles by suppressing inward shrinkage due to capillary forces during drying and achieves a high in-plane orientation of graphene nanosheets,thereby creating a fast in-plane heat transfer channel.The composite films(GNS/ANF-60 wt%)with eliminated graphene nanosheets wrinkles showed a significant increase in thermal conductivity(146 W m^(−1)K^(−1))and tensile strength(207 MPa).The combination of these excellent properties enables the GNS/ANF composite films to be effectively used for cooling flexible LED chips and smartphones,showing promising applications in the thermal management of high-power electronic devices.
基金the Hong Kong Polytechnic University(Q-CDBG),the Science and Technology Program of Guangdong Province of China(2020A0505090001)the Research Grants Council of the Hong Kong Special Administrative Region,China(Project No.PolyU152178/20E)+2 种基金the National Natural Science Foundation of China(22379052)the Natural Science Foundation of Guangdong(No.2022A1515011667)China Postdoctoral Science Foundation(2021T140268).
文摘Inactive elemental doping is commonly used to improve the structural stability of high-voltage layered transition-metal oxide cathodes.However,the one-step co-doping strategy usually results in small grain size since the low diffusivity ions such as Ti^(4+)will be concentrated on grain boundaries,which hinders the grain growth.In order to synthesize large single-crystal layered oxide cathodes,considering the different diffusivities of different dopant ions,we propose a simple two-step multi-element co-doping strategy to fabricate core–shell structured LiCoO_(2)(CS-LCO).In the current work,the high-diffusivity Al^(3+)/Mg^(2+)ions occupy the core of single-crystal grain while the low diffusivity Ti^(4+)ions enrich the shell layer.The Ti^(4+)-enriched shell layer(~12 nm)with Co/Ti substitution and stronger Ti–O bond gives rise to less oxygen ligand holes.In-situ XRD demonstrates the constrained contraction of c-axis lattice parameter and mitigated structural distortion.Under a high upper cut-off voltage of 4.6 V,the single-crystal CS-LCO maintains a reversible capacity of 159.8 mAh g^(−1)with a good retention of~89%after 300 cycles,and reaches a high specific capacity of 163.8 mAh g^(−1)at 5C.The proposed strategy can be extended to other pairs of low-(Zr^(4+),Ta^(5+),and W6+,etc.)and high-diffusivity cations(Zn^(2+),Ni^(2+),and Fe^(3+),etc.)for rational design of advanced layered oxide core–shell structured cathodes for lithium-ion batteries.
基金the financial support of the National Natural Science Foundation of China(grant number 22005145)the Natural Science Foundation of Jiangsu Province(grant number BK20180495,BK20180698)+1 种基金the Opening Project of Key Laboratory of Special Energy Materials(Nanjing University of Science and Technology)the Fundamental Research Funds for the Priority Academic Program Development of Jiangsu Higher Education Institutions(grant number 30919011404)。
文摘Hydroxyl-terminated polybutadiene/toluene diisocyanate(HTPB/TDI)system is widely used in composite solid propellants.The migrations of plasticizers and water molecules from solid propellants and surrounding environment to the inhibitor have always been the important issues.This study focuses on the preparation,characterization and anti-migration behavior of graphene oxide(GO)/HTPB nanocomposite liner.The GO/HTPB(GH)composite liners affect the migration of small molecules through a tighter cross-linked structure and weakening function of small molecule adsorption.The anti-migration performance of the liner at different temperatures was analyzed,and the influence of the added amount of GO on the anti-migration performance and adhesion performance was also systematically studied.The overall performance of the liner is optimized when the amount of GO filler is 0.3 wt%.After adding 0.3 wt%GO,the concentration of dioctyl sebacate(DOS)migrated into the liner is decreased by 23.28%,and the concentration of water molecules is decreased by 51.89%,indicating that the introduction of GO can significantly improve the anti-migration performance of the liner.In addition,the bond strength is greatly increased from 0.25 MPa to 0.95 MPa,which meets the application requirements of the current propellant system.This research provides an important way for the preparation of structure-function synergistic anti-migration composite liners.
文摘BACKGROUND Chronic heart failure(CHF)is a serious and prevalent condition characterized by impaired cardiac function and inflammation.Standard therapy for CHF has limitations,prompting the exploration of alternative treatments.Recombinant human brain natriuretic peptide(BNP)has emerged as a potential therapy,with evidence suggesting that it can improve cardiac function and reduce inflammation in patients with CHF.However,further research is required to determine the efficacy and safety of lyophilized recombinant human BNP in CHF patients and its impact on microinflammatory status.This study aimed to investigate the effects of lyophilized recombinant human BNP therapy on CHF patients’cardiac function and microinflammatory status.AIM To investigate the effects of freeze-dried recombinant human BNP therapy on cardiac function and microinflammatory status in patients with CHF.METHODS In total,102 CHF patients admitted to our hospital from January 2021 to January 2022 were randomly assigned to control and observation groups(n=51 patients/group).The control patients were treated with standard HF therapy for 3 d,whereas the observational patients were injected with the recombinant human BNP for 3 d.Clinical efficacy,inflammatory factor levels,myocardial damage,cardiac function before and after the treatment,and adverse reactions during treatment were compared between the two groups.RESULTS The overall clinical efficacy was higher in the observation group than in the control group.Compared with baseline,serum hypersensitive C-reactive protein,N-terminal proBNP,and troponin I level,and physical,emotional,social,and economic scores were lower in both groups after treatment,with greater reductions in levels and scores noted in the observation group than in the control group.The overall incidence of adverse reactions in the observation group was not significantly different compared with that in the control group(P>0.05).CONCLUSION Freeze-dried recombinant human BNP therapy can improve heart function and enhance microinflammatory status,thereby improving overall quality of life without any obvious side effects.This therapy is safe and reliable.
基金supported in part by the Open Fund of Advanced Cryptography and System Security Key Laboratory of Sichuan Province under Grant SKLACSS-202102in part by the Intelligent Terminal Key Laboratory of Sichuan Province under Grant SCITLAB-1019.
文摘The vehicular sensor network (VSN) is an important part of intelligent transportation, which is used for real-timedetection and operation control of vehicles and real-time transmission of data and information. In the environmentofVSN, massive private data generated by vehicles are transmitted in open channels and used by other vehicle users,so it is crucial to maintain high transmission efficiency and high confidentiality of data. To deal with this problem, inthis paper, we propose a heterogeneous fault-tolerant aggregate signcryption scheme with an equality test (HFTASET).The scheme combines fault-tolerant and aggregate signcryption,whichnot onlymakes up for the deficiency oflow security of aggregate signature, but alsomakes up for the deficiency that aggregate signcryption cannot tolerateinvalid signature. The scheme supports one verification pass when all signcryptions are valid, and it supportsunbounded aggregation when the total number of signcryptions grows dynamically. In addition, this schemesupports heterogeneous equality test, and realizes the access control of private data in different cryptographicenvironments, so as to achieve flexibility in the application of our scheme and realize the function of quick searchof plaintext or ciphertext. Then, the security of HFTAS-ET is demonstrated by strict theoretical analysis. Finally, weconduct strict and standardized experimental operation and performance evaluation, which shows that the schemehas better performance.
文摘BACKGROUND The multidisciplinary team(MDT)has been carried out in many large hospitals now.However,given the costs of time and money and with little strong evidence of MDT effectiveness being reported,critiques of MDTs persist.AIM To evaluate the effects of MDTs on patients with synchronous colorectal liver metastases and share our opinion on management of synchronous colorectal liver metastases.METHODS In this study we collected clinical data of patients with synchronous colorectal liver metastases from February 2014 to February 2017 in the Chinese People’s Liberation Army General Hospital and subsequently divided them into an MDT+group and an MDT-group.In total,93 patients in MDT+group and 169 patients in MDT-group were included totally.RESULTS Statistical increases in the rate of chest computed tomography examination(P=0.001),abdomen magnetic resonance imaging examination(P=0.000),and preoperative image staging(P=0.0000)were observed in patients in MDT+group.Additionally,the proportion of patients receiving chemotherapy(P=0.019)and curative resection(P=0.042)was also higher in MDT+group.Multivariable analysis showed that the population of patients assessed by MDT meetings had higher 1-year[hazard ratio(HR)=0.608,95%confidence interval(CI):0.398-0.931,P=0.022]and 5-year(HR=0.694,95%CI:0.515-0.937,P=0.017)overall survival.CONCLUSION These results proved that MDT management did bring patients with synchronous colorectal liver metastases more opportunities for comprehensive examination and treatment,resulting in better outcomes.
基金This research was funded by the National Natural Science Foundation of China(51974052)(51804061)the Chongqing Research Program of Basic Research and Frontier Technology(cstc2019jcyj-msxmX0199).
文摘During the drilling process,stick-slip vibration of the drill string is mainly caused by the nonlinear friction gen-erated by the contact between the drill bit and the rock.To eliminate the fatigue wear of downhole drilling tools caused by stick-slip vibrations,the Fractional-Order Proportional-Integral-Derivative(FOPID)controller is used to suppress stick-slip vibrations in the drill string.Although the FOPID controller can effectively suppress the drill string stick-slip vibration,its structure isflexible and parameter setting is complicated,so it needs to use the cor-responding machine learning algorithm for parameter optimization.Based on the principle of torsional vibration,a simplified model of multi-degree-of-freedom drill string is established and its block diagram is designed.The continuous nonlinear friction generated by cutting rock is described by the LuGre friction model.The adaptive learning strategy of genetic algorithm(GA),particle swarm optimization(PSO)and particle swarm optimization improved(IPSO)by arithmetic optimization(AOA)is used to optimize and adjust the controller parameters,and the drill string stick-slip vibration is suppressed to the greatest extent.The results show that:When slight drill string stick-slip vibration occurs,the FOPID controller optimized by machine learning algorithm has a good effect on suppressing drill string stick-slip vibration.However,the FOPID controller cannot get the drill string system which has fallen into serious stick-slip vibration(stuck pipe)out of trouble,and the machine learning algorithm is required to mark a large amount of data on adjacent Wells to train the model.Set a reasonable range of drilling parameters(weight on bit/drive torque)in advance to avoid severe stick-slip vibration(stuck pipe)in the drill string system.
基金Supported by Hunan Provincial University Innovation Platform Open Fund Project(19K049)。
文摘With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux extraction and ultrasound-assisted extraction,and the effects of different extraction methods the contents of total flavonoids in P.edulis from different areas were compared.The results showed that the best extraction time for P.edulis in Yunnan Province was 20 min,and that for Guangdong and Guangxi Zhuang Autonomous Region was 30 min.The yield of total flavonoids from P.edulis extracted by the condensation reflux extraction method was relatively better.The content of total flavonoids in P.edulis in Yunnan was the highest with an average content of 0.2557%,while the average content of total flavonoids in P.edulis in Guangdong was the lowest with an average content of 0.2108%.
文摘Background:Hepatic fibrosis is a common chronic liver disease in clinic,the purpose of our study is to explore potential biomarkers to provide a theoretical basis for the treatment of liver fibrosis with pirfenidone.Methods:We downloaded a gene-sequencing dataset and a single-cell dataset from the GEO database and pirfenidone target genes from three different databases.First,we performed GO,KEGG,and DO analysis on pirfenidone target genes.Then,we grouped the liver tissue sequencing data(GSE162694)in the sequencing data set(N-F0 group and F1-F4 group)and performed gene expression differential analysis on these two groups,weighted gene co-expression network analysis and gene Enrichment analysis.Finally,we intersected the significantly upregulated genes in the F1-F4 group with the pirfenidone target genes and performed PPI network analysis.In order to further explore the expression of both pirfenidone drug target genes and liver fibrosis disease genes(PDLFG)in different immune cells of liver tissue,we used the CD45+cell data in the GSE136103 data set for further analysis.Results:A subnetwork consisting of CDC42,HNF4A,BHLHE40,CCDC71L,NR1H3,TNF,MGLL,GPT,SCD and PLIN1 was screened out,and by analysis,we finally identified the SCD as PDLFG.In single-cell sequencing analysis,we found that SCD was highly expressed in M2-polarized macrophages.Conclusion:SCD may be an important target protein to inhibit the progression of liver fibrosis.
基金supports by the Natural Science Foundation of Jilin Province(20210101220JC)Health commission project of Jilin Province(2021LC042).
文摘Tea polyphenols(TP)is a class of polyhydroxy compounds isolated from tea.Modern biological and medical studies have shown that TP has many pharmacological activities,such as anti-inflammatory,anti-virus,anti-oxidation,anti-tumor and anti-radiation.Furthermore,these substances can be used as a potential drug component to positively guide the occurrence and development of certain diseases.Furthermore,because of the activities of TP,such as anti-oxidation and anti-bacteria,it can be applied in food preservation,color preservation,deodorization,and treatment of food processing by-products.Based on the research progress of TP in recent years,this paper summarizes the pharmacological activities of TP and expounds on its application potential in the field of food.In order to provide a theoretical reference for the research,development and utilization of TP.
文摘该文针对多源时变干扰影响的双三相永磁同步电机系统,研究其基波平面内的调速控制问题和谐波平面内的谐波电流抑制问题。首先,在基波平面采用非串级控制结构,通过构造广义比例积分观测器(generalized proportional integral observer,GPIO)估计转速环的多源快变干扰;然后,针对q轴电流的过流保护问题,在传统比例微分反馈控制器的基础上利用障碍函数设计思想,结合干扰估计信息,得到基于GPIO的电流约束复合控制器;其次,在谐波平面,通过设计2个GPIO精准估计电流环的多源快变干扰,并与比例反馈控制器结合形成复合控制器来抑制2个电流环中的谐波电流。最后,给出严谨的稳定性分析,并通过对比实验验证所提方法的有效性。
基金supported by the National Natural Science Foundation of China(Nos.52225107,U2106224,U1906234,51822904,and U1706223)the Fundamental Research Funds for the Central Universities(No.202041004)
文摘Deep-sea sediment disturbance may occur when collecting polymetallic nodules,resulting in the creation of plumes that could have a negative impact on the ecological environment.This study aims to investigate the potential solution of using polyaluminum chloride(PAC)in the water jet.The effects of PAC are examined through a self-designed simulation system for deep-sea polymetallic nodule collection and sediment samples from a potential deep-sea mining area.The experimental results showed that the optimal PAC dose was found to be 0.75 g/L.Compared with the test conditions without the addition of PAC,the presence of PAC leads to a reduction in volume,lower characteristic turbidity,smaller diffusion velocity,and shorter settling time of the plume.This indicates that PAC inhibits the entire development process of the plume.The addition of PAC leads to the flocculation of mm-sized particles,resulting in the formation of cm-sized flocs.The flocculation of particles decreases the rate of erosion on the seabed by around 30%.This reduction in erosion helps to decrease the formation of plumes.Additionally,when the size of suspended particles increases,it reduces the scale at which they diffuse.Furthermore,the settling velocity of flocs(around 10^(-2) m/s)is much higher that of compared to sediment particles(around 10^(-5) m/s),which effectively reduces the amount of time the plume remains in suspension.
基金the support from the National Key R&D Program of China(No.2022YFA1503801)the National Natural Science Foundation of China(No.22172190,No.22202232 and No.22109171)。
文摘Surface-supported isolated atoms in single-atom catalysts(SACs)grant maximum utilization of metals in heterogeneous catalysis.Herein,we report a feasible pyrolysis strategy to synthesize Pd single atoms by thermally melting Pd nanoparticles on an oxygen-vacancy-rich tungsten-oxide matrix at reduction atmosphere.Near ambient pressure X-ray photoelectron spectroscopy was used to monitor the formation of zero-valence Pd single atoms and the increased metallic feature of WO_(3-x)substrate.Accordingly,the as-obtained zero-valence Pd single-atom catalyst exhibits a markedly boosted HER activity with a low overpotential(η_(10)=70 mV)at the current density of 10 mA/cm2and a small Tafel slope(b=68 mV/dec),nearly 150 mV and a 3,0-fold enhancement than those of Pd nanoparticles(η_(10)=220 mV,b=133 mV/dec)under the same conditions.In addition,quasi in situ XPS results suggest the hydrogen spillover effect is more likely to occur on Pd single atoms during the electrochemical process.Our work may pave an interesting route for the rational design of highly-efficient single-atom catalysts,and the elucidation of corresponding enhanced reaction mechanisms by the utilization of advanced characterization techniques.
基金supported in part by the National Natural Science Foundation of China under Grant 51907116in part sponsored by Natural Science Foundation of Shanghai 22ZR1425400sponsored by Shanghai Rising-Star Program 23QA1404000.
文摘Amidst the swift advancement of new power systems and electric vehicles,inverter-fed machines have progressively materialized as a pivotal apparatus for efficient energy conversion.Stator winding turn insulation failure is the root cause of inverter-fed machine breakdown.The online monitoring of turn insulation health can detect potential safety risks promptly,but faces the challenge of weak characteristics of turn insulation degradation.This study proposes an innovative method to evaluate the turn insulation state of inverter-fed machines by utilizing the fractional Fourier transform with a Mel filter(FrFT-Mel).First,the sensitivity of the high-frequency(HF)switching oscillation current to variations in turn insulation was analyzed within the fractional domain.Subsequently,an improved Mel filter is introduced,and its structure and parameters are specifically designed based on the features intrinsic to the common-mode impedance resonance point of the electrical machine.Finally,an evaluation index was proposed for the turn insulation state of inverter-fed machines.Experimental results on a 3kW permanent magnet synchronous machine(PMSM)demonstrate that the proposed FrFT-Mel method significantly enhances the sensitivity of turn insulation state perception by approximately five times,compared to the traditional Fourier transform method.
基金the National Key Research and Development Program of China(Grant Number 2021YFB1714600)the National Natural Science Foundation of China(Grant Number 52075195)the Fundamental Research Funds for the Central Universities,China through Program No.2172019kfyXJJS078.
文摘With the continuous advancement in topology optimization and additive manufacturing(AM)technology,the capability to fabricate functionally graded materials and intricate cellular structures with spatially varying microstructures has grown significantly.However,a critical challenge is encountered in the design of these structures–the absence of robust interface connections between adjacent microstructures,potentially resulting in diminished efficiency or macroscopic failure.A Hybrid Level Set Method(HLSM)is proposed,specifically designed to enhance connectivity among non-uniform microstructures,contributing to the design of functionally graded cellular structures.The HLSM introduces a pioneering algorithm for effectively blending heterogeneous microstructure interfaces.Initially,an interpolation algorithm is presented to construct transition microstructures seamlessly connected on both sides.Subsequently,the algorithm enables the morphing of non-uniform unit cells to seamlessly adapt to interconnected adjacent microstructures.The method,seamlessly integrated into a multi-scale topology optimization framework using the level set method,exhibits its efficacy through numerical examples,showcasing its prowess in optimizing 2D and 3D functionally graded materials(FGM)and multi-scale topology optimization.In essence,the pressing issue of interface connections in complex structure design is not only addressed but also a robust methodology is introduced,substantiated by numerical evidence,advancing optimization capabilities in the realm of functionally graded materials and cellular structures.