The present study screened a human fetal brain cDNA library to find the proteins that interact with mutant superoxide dismutase 1 （SOD1） using a yeast two-hybrid system. Using BLAST software, 15 real proteins which ...The present study screened a human fetal brain cDNA library to find the proteins that interact with mutant superoxide dismutase 1 （SOD1） using a yeast two-hybrid system. Using BLAST software, 15 real proteins which interacted with mutant SOD1 were obtained, including 8 known proteins （protein tyrosine-phosphatase non-receptor type 2, TBCl D4, protein kinase family, splicing factor, arginine/serine-rich 2, SRC protein tyrosine kinase Fyn, β-sarcoglycan; glycine receptor a2, microtubule associated protein/microtubule affinity-regulating kinase 1, ferritin H chain）, and 7 unknown proteins. Results demonstrated interaction of mutant SOD1 with microtubule associated protein/microtubule affinity-regulating kinase 1 and β-sarcoglycan.展开更多
This paper proposes a fault estimation method for sampled data systems with sensor faults. The sampled data system is firstly discretized to obtain a discrete time model. Then a descriptor system is constructed to des...This paper proposes a fault estimation method for sampled data systems with sensor faults. The sampled data system is firstly discretized to obtain a discrete time model. Then a descriptor system is constructed to describe the discretized system with sensor faults. Based on the descriptor system representation a bank of observers are designed to isolate and estimate the sensor faults. These observers can be synthesized by the linear matrix inequality (LMI) technique and sufficient conditions for the existence of these observers are derived. Finally the effectiveness is ascertained by an aircraft simulation example which is in the proposed method.展开更多
This paper proposes a state estimation method for a class of norm bounded non linear sampled data descriptor systems using the Kalman filtering method. The descriptor model is firstly discretized to obtain a discrete ...This paper proposes a state estimation method for a class of norm bounded non linear sampled data descriptor systems using the Kalman filtering method. The descriptor model is firstly discretized to obtain a discrete time non singular one. Then a model of robust extended Kalman filter is proposed for the state estimation based on the discretized non linear non singular system. As parameters are introduced in for transforming descriptor systems into non singular ones there exist uncertainties in the state of the systems. To solve this problem an optimized upper bound is proposed so that the convergence of the estimation error co variance matrix is guaranteed in the paper. A simulating example is proposed to verify the validity of this method at last.展开更多
In this paper,the problem of designing robust H-infinity output feedback controller and l2-gain controller are investigated for a class of discrete-time singular piecewise-affine systems with input saturation and stat...In this paper,the problem of designing robust H-infinity output feedback controller and l2-gain controller are investigated for a class of discrete-time singular piecewise-affine systems with input saturation and state constraints. Based on a singular piecewise Lyapunov function combined with S-procedure and some matrix inequality convexifying techniques,the H-infinity stabilization condition is established and the l2-gain controller is investigated,and meanwhile,the input saturation disturbance tolerance condition is proposed. Under energy bounded disturbance,the domain of attraction is well estimated and the l2-gain controller is designed in some restricted region. It is shown that the controller gains can be obtained by solving a family of LMIs parameterized by one or two scalar variables. Meanwhile,by using the corresponding optimization methods,the domain of attraction and the disturbance tolerance level is maximized,and the H-infinity performance γ is minimized.Finally,numerical examples are given to illustrate the effectiveness of the proposed design methods.展开更多
In this paper, a robust sensor fault diagnosis observer with non-singular structure is proposed for a class of linear sampled-data descriptor system with state time-vary delay. Firstly, a sampled-data descriptor model...In this paper, a robust sensor fault diagnosis observer with non-singular structure is proposed for a class of linear sampled-data descriptor system with state time-vary delay. Firstly, a sampled-data descriptor model with time-vary delay is proposed and transformed into a discrete-time non-singular one. Then, a robust sensor fault diagnosis observer is proposed based on the state estimation error and the measurement residual, this observer can guarantee the robustness of the residual against the augmented disturbance and the sensor fault, which means the H∞ performance index is satisfied. As the confining matrix of the designed observer parameters does not meet the Linear Matrix Inequality (LMI), a cone complementary linearization (CCL) algorithm is proposed to solve this problem. The decision logic of the residual is obtained by the residual evaluation function. Simulation results show the effectiveness of the method.展开更多
[Objectives]To explore the process of simultaneous extracting total flavonoids and chlorogenic acid from Flos Lonicerae by pressure assisted extraction.[Methods]Based on the single factor experiment,orthogonal experim...[Objectives]To explore the process of simultaneous extracting total flavonoids and chlorogenic acid from Flos Lonicerae by pressure assisted extraction.[Methods]Based on the single factor experiment,orthogonal experiments were carried out to investigate the effects of solvent concentration,solid-to-liquid ratio,extraction pressure,extraction time and extraction temperature on the extraction rate of total flavonoids and chlorogenic acid.[Results]The results showed that the extraction pressure had a significant effect on the extraction of two kinds of chemical constituents from F.Lonicerae.The optimum process conditions were as follows:solvent concentration was 60%,solid-liquid ratio was 1∶20(g/mL),extraction pressure was 2 MPa,extraction time was 30 min,extraction temperature was 70℃.The process conditions are stable,and the extraction efficiency is higher than that of ultrasonic assisted extraction method.Under the test conditions,the extraction rates of total flavonoids and chlorogenic acids were respectively 15.66%and 3.89%.[Conclusions]This study provides a new theoretical basis for the development and utilization of F.Lonicerae.展开更多
[Objectives] This study aimed to optimize the conditions for pressurized synchronous extraction of volatile oils, total flavonoids and tannic acid from Artemisia argyi .[Methods] Single factor experiments and orthogon...[Objectives] This study aimed to optimize the conditions for pressurized synchronous extraction of volatile oils, total flavonoids and tannic acid from Artemisia argyi .[Methods] Single factor experiments and orthogonal experiments were conducted.[Results] Pressurization had a significant effect on the extraction rate of chemical constituents of A. argyi . The optimal conditions for pressurized synchronous extraction of volatile oils, total flavonoids and tannic acid from A. argyi were as follows: solvent concentration of 70%, solid to liquid ratio of 1∶ 30 (g/mL), extraction pressure of 0.9 MPa, extraction time of 40 min and extraction temperature of 90 ℃. Under the optimal extraction conditions, the yields of volatile oils, total flavonoids and tannic acid were 0.852%, 4.66% and 6.79%, respectively.[Conclusions] Compared with other extraction methods, the pressurized assistant solvent extraction method can achieve the synchronous extraction of volatile oils, total flavonoids and tannic acid from A. argyi . The process is stable, short in extraction time, high in solvent utilization rate and ideal in extraction effect of the three components from A. argyi .展开更多
Starting from the characteristics of big data,the cognition and thinking of contemporary college students have shown new features.Therefore,it is necessary to use the technical means of big data to formulate thinking ...Starting from the characteristics of big data,the cognition and thinking of contemporary college students have shown new features.Therefore,it is necessary to use the technical means of big data to formulate thinking under big data,combined with critical thinking.By doing so,students can finally nurture a correct attitude and better morality and even complete the fundamental task of higher education.展开更多
This paper aims to tackle the calculation efficiency problem raised in the cavitation-flow simulation of the aviation centrifugal pump due to the fading-away interface resulting from the dissipation of numerics used i...This paper aims to tackle the calculation efficiency problem raised in the cavitation-flow simulation of the aviation centrifugal pump due to the fading-away interface resulting from the dissipation of numerics used in the phase-change control equation for unstructured-grid multiphase flow,and due to the limitation of flow time-step in whole flow regimes,the control equation of vapor–liquid two-phase flow considering cavitation mass transport is established firstly,modifying the momentum equation by introducing the surface tension,and adding the artificial convective flow to the phase equation to solve the numerical dissipation problem.Secondly,in consideration of the local time step principle and based on the multi-dimensional general limiter algorithm with explicit solutions under the OpenFOAM platform,a solution method of steady-state VOF (Volume of Fluid) model considering cavitation two-phase change is constructed,and the feasibility of this method is verified by NACA hydrofoil and NASA flat plate inducer.Finally,based on the platform developed,the cavitation performance of an aviation centrifugal pump inducer is analyzed.The research results show that the error of the calculated cavitation pressure distribution for NACA hydrofoil between the simulation test and the experimental-test is less than 5%,and the maximum error of calculated cavitation number at pump head dropping for NASA high-speed flat plate inducer between the simulation test and the experimental-test is 2.1%.The cavitation area observed in the simulation test is the same as that obtained in the high-speed photography test.Based on the OpenFOAM simulation method,the position of pump head dropping of the fuel centrifugal pump can be accurately captured.The error of the calculated cavitation number at pump head dropping between the simulation test and the experimental test is about 3.7%,showing high calculation accuracy.展开更多
Nonalcoholic fatty liver disease(NAFLD)is characterized by excessive accumulation of hepatic lipids and metabolic stress-induced liver injury.There are currently no approved effective pharmacological treatments for NA...Nonalcoholic fatty liver disease(NAFLD)is characterized by excessive accumulation of hepatic lipids and metabolic stress-induced liver injury.There are currently no approved effective pharmacological treatments for NAFLD.Traditional Chinese medicine(TCM)has been used for centuries to treat patients with chronic liver diseases without clear disease types and mechanisms.More recently,TCM has been shown to have unique advantages in the treatment of NAFLD.We performed a systematic review of the medical literature published over the last two decades and found that many TCM formulas have been reported to be beneficial for the treatment of metabolic dysfunctions,including Potentilla discolor Bunge(PDB).PDB has a variety of active compounds,including flavonoids,terpenoids,organic acids,steroids and tannins.Many compounds have been shown to exhibit a series of beneficial effects for the treatment of NAFLD,including anti-oxidative and anti-inflammatory functions,improvement of lipid metabolism and reversal of insulin resistance.In this review,we summarize potential therapeutic effects of TCM formulas for the treatment of NAFLD,focusing on the medicinal properties of natural active compounds from PDB and their underlying mechanisms.We point out that PDB can be classified as a novel candidate for the treatment and prevention of NAFLD.展开更多
background Intravenous tissue plasminogen activator with or without mechanical thrombectomy during the acute phase are approved therapies for ischaemic stroke.Due to the short treatment time window(<6 hours)and oft...background Intravenous tissue plasminogen activator with or without mechanical thrombectomy during the acute phase are approved therapies for ischaemic stroke.Due to the short treatment time window(<6 hours)and often treatment failure,these patients would still have an intracranial arterial occlusion(IAO).It is unclear whether these patients can benefit from subsequent interventional recanalizationof their occluded artery in the subacute phase.In this retrospective study,we have examined the efficacy and safety in patients who have received either percutaneous transluminal angioplasty(PTA)or percutaneous transluminal angioplasty and stenting(PTAS)for IAO in the subacute phase of their stroke.Methods Patients with subacute symptomatic ischaemic stroke caused by IAO were assessed to identify the responsible artery and low perfusion areas by CT angiography,MR angiography or digital subtraction angiography.In eligible patients,a PTA or PTAS was performed to reopen the occluded artery.Regular antithrombotic therapy,use of statins,control of risk factors and rehabilitation therapy were prescribed after the procedure.All patients had regular follow-up up to 12 months.results PTA or PTAS was performed in 16 patients with cerebral infarction caused by IAO in the subacute phase.After the procedure,12 cases were recanalized,two were partially recanalized and two failed to open.One patient with left C6 segment occlusion of the carotid artery had a central retinal artery embolism after PTAS.The perioperative adverse events were 6.25%.At 3 months,the distribution of modified Rankin scale scores was 0(seven cases),1(three cases),2(five cases)and 3(one case).conclusion Selective PTA or PTAS could be performed in ischaemic stroke patients with a small infarct size and large area of hypoperfusion from an occluded large cerebral artery after the acute phase.It may improve neurological dysfunction and reduce the incidence of disability.展开更多
Large-scale gold mineralization during the Early Cretaceous is identified in the Jiao-dong Peninsula of China.Sources of ore-forming fluids remain debated.We study the Qilishan gold deposit in the northwestern Jiaodon...Large-scale gold mineralization during the Early Cretaceous is identified in the Jiao-dong Peninsula of China.Sources of ore-forming fluids remain debated.We study the Qilishan gold deposit in the northwestern Jiaodong Peninsula with detailed mineralogical observation and in-situ sulfur isotope analyses,in order to reveal the gold occurrence and the origin of ore-forming fluids.The Qilishan gold deposit is mainly clastic altered rock-type in mineralization,and ore minerals are visible native gold,electrum,pyrite,chalcopyrite and galena,gangue minerals as quartz,sericite and calcite.The gold occurrence includes inclusion and intergranular types,formed within pyrites and chalcopy-rites and along their fissures.In-situ sulfur isotope analysis of gold-bearing sulfides suggests that the Qilishan deposit is enriched in heavy sulfur,withδ34S values mainly from+8.0‰to+12.0‰.δ34S val-ues increase gradually with the fluid evolution from the early to late stages,which is interpreted to be related to the loss of sulfur via sulfide precipitation.The crystallization of sulfides from hydrothermal fluids may have triggered the instability of Au(HS)2,and finally led to gold precipitation.Combined with sulfur isotope compositions of other gold deposits(n=43)and wall-rocks in the Jiaodong Peninsu-la,it is proposed that the ore-forming fluids were probably not directly originated from metamorphic wall-rocks(e.g.,Jiaodong Group).Moreover,the relatively long time interval rules out the possibility that the gold mineralization(ca.120 Ma)was associated with granitic magma activities(mostly 160-150 Ma).Possible ore genesis scenario is that,long-term subduction of slabs(e.g.,the Paleo-Pacific)with gold-enriched pyritic materials and crustal sedimentary rocks resulted in both high Au contents and positiveδ34S values of sulfur in the lithospheric mantle below the North China Craton.Subse-quently,devolatilization of the metasomatized mantle produced auriferous fluids that migrated up-ward along translithospheric fault systems,and gold finally precipitated in favorable structural posi-tions,generating the world-class Jiaodong deposits in the Early Cretaceous.展开更多
Mechanically pumped two-phase loop(MPTL)which is a prominent two-phase heat transfer technology presents a promising prospect in thermal control for space payload.However,transient behavior of MPTL caused by phase-cha...Mechanically pumped two-phase loop(MPTL)which is a prominent two-phase heat transfer technology presents a promising prospect in thermal control for space payload.However,transient behavior of MPTL caused by phase-change and heat sources load-on/off in simulated space environment is rarely reported.In the present study,one MPTL setup was designed and constructed,and experimentally studied.Particularly,a novel two-phase thermally-controlled accumulator integrated with passive cooling measure and three capillary structures was designed as the temperature-control device.Dynamic behavior of the start-up,temperature control,and temperature adjustment were monitored;meanwhile,thermodynamic behavior within the proposed accumulator,the operating behavior as well as the heat and mass transfer behavior between the main loop and the accumulator were revealed.The results show that the fluid management function of the capillary structures for the novel accumulator is verified.The working point of the MPTL system can be adjusted by changing the temperature control point of the accumulator and it is little influenced by external heat flux and heat sources on/off.Pressure-drop oscillations which are manifested as fluctuations of temperature and pressure can be observed after phase changing due to the compressible volume within the accumulator and the negative-slope portion of the internal pressure.展开更多
Small-diameter tissue-engineered vascular grafts(sdTEVGs)with hyperglycemia resistance have not been constructed.The intimal hyperplasia caused by hyperglycemia remains problem to hinder the patency of sdTEVGs.Here,in...Small-diameter tissue-engineered vascular grafts(sdTEVGs)with hyperglycemia resistance have not been constructed.The intimal hyperplasia caused by hyperglycemia remains problem to hinder the patency of sdTEVGs.Here,inspired by bionic regulation of nerve on vascular,we found the released neural exosomes could inhibit the abnormal phenotype transformation of vascular smooth muscle cells(VSMCs).The transformation was a prime culprit causing the intimal hyperplasia of sdTEVGs.To address this concern,sdTEVGs were modified with an on-demand programmable dual-responsive system of ultrathin hydrogels.An external primary Reactive Oxygen Species(ROS)-responsive Netrin-1 system was initially triggered by local inflammation to induce nerve remolding of the sdTEVGs overcoming the difficulty of nerve regeneration under hyperglycemia.Then,the internal secondary ATP-responsive DENND1A(guanine nucleotide exchange factor)system was turned on by the neurotransmitter ATP from the immigrated nerve fibers to stimulate effective release of neural exosomes.The results showed nerve fibers grow into the sdTEVGs in diabetic rats 30 days after transplantation.At day 90,the abnormal VSMCs phenotype was not detected in the sdTEVGs,which maintained long-time patency without intima hyperplasia.Our study provides new insights to construct vascular grafts resisting hyperglycemia damage.展开更多
An adaptive multi-penalty discontinuous Galerkin method(AMPDG)for the diffusion problem is considered.Convergence and quasi-optimality of the AM-PDG are proved.Compared with the analyses for the adaptive finite elemen...An adaptive multi-penalty discontinuous Galerkin method(AMPDG)for the diffusion problem is considered.Convergence and quasi-optimality of the AM-PDG are proved.Compared with the analyses for the adaptive finite element method or the adaptive interior penalty discontinuous Galerkin method,extra works are done to overcome the difficulties caused by the additional penalty terms.展开更多
基金the National Natural Science Foundation of China, No. 30300116
文摘The present study screened a human fetal brain cDNA library to find the proteins that interact with mutant superoxide dismutase 1 （SOD1） using a yeast two-hybrid system. Using BLAST software, 15 real proteins which interacted with mutant SOD1 were obtained, including 8 known proteins （protein tyrosine-phosphatase non-receptor type 2, TBCl D4, protein kinase family, splicing factor, arginine/serine-rich 2, SRC protein tyrosine kinase Fyn, β-sarcoglycan; glycine receptor a2, microtubule associated protein/microtubule affinity-regulating kinase 1, ferritin H chain）, and 7 unknown proteins. Results demonstrated interaction of mutant SOD1 with microtubule associated protein/microtubule affinity-regulating kinase 1 and β-sarcoglycan.
基金Sponsored by the National Natural Science Foundation of China(Grant No.61004038)
文摘This paper proposes a fault estimation method for sampled data systems with sensor faults. The sampled data system is firstly discretized to obtain a discrete time model. Then a descriptor system is constructed to describe the discretized system with sensor faults. Based on the descriptor system representation a bank of observers are designed to isolate and estimate the sensor faults. These observers can be synthesized by the linear matrix inequality (LMI) technique and sufficient conditions for the existence of these observers are derived. Finally the effectiveness is ascertained by an aircraft simulation example which is in the proposed method.
基金Sponsored by the National Natural Science Foundation of China(Grant No.61021002)
文摘This paper proposes a state estimation method for a class of norm bounded non linear sampled data descriptor systems using the Kalman filtering method. The descriptor model is firstly discretized to obtain a discrete time non singular one. Then a model of robust extended Kalman filter is proposed for the state estimation based on the discretized non linear non singular system. As parameters are introduced in for transforming descriptor systems into non singular ones there exist uncertainties in the state of the systems. To solve this problem an optimized upper bound is proposed so that the convergence of the estimation error co variance matrix is guaranteed in the paper. A simulating example is proposed to verify the validity of this method at last.
基金Sponsored by the National Natural Science Foundation of China(Grant No.61004038)
文摘In this paper,the problem of designing robust H-infinity output feedback controller and l2-gain controller are investigated for a class of discrete-time singular piecewise-affine systems with input saturation and state constraints. Based on a singular piecewise Lyapunov function combined with S-procedure and some matrix inequality convexifying techniques,the H-infinity stabilization condition is established and the l2-gain controller is investigated,and meanwhile,the input saturation disturbance tolerance condition is proposed. Under energy bounded disturbance,the domain of attraction is well estimated and the l2-gain controller is designed in some restricted region. It is shown that the controller gains can be obtained by solving a family of LMIs parameterized by one or two scalar variables. Meanwhile,by using the corresponding optimization methods,the domain of attraction and the disturbance tolerance level is maximized,and the H-infinity performance γ is minimized.Finally,numerical examples are given to illustrate the effectiveness of the proposed design methods.
基金Sponsored by the National Natural Science Foundation of China(Grant No.61021002)
文摘In this paper, a robust sensor fault diagnosis observer with non-singular structure is proposed for a class of linear sampled-data descriptor system with state time-vary delay. Firstly, a sampled-data descriptor model with time-vary delay is proposed and transformed into a discrete-time non-singular one. Then, a robust sensor fault diagnosis observer is proposed based on the state estimation error and the measurement residual, this observer can guarantee the robustness of the residual against the augmented disturbance and the sensor fault, which means the H∞ performance index is satisfied. As the confining matrix of the designed observer parameters does not meet the Linear Matrix Inequality (LMI), a cone complementary linearization (CCL) algorithm is proposed to solve this problem. The decision logic of the residual is obtained by the residual evaluation function. Simulation results show the effectiveness of the method.
基金Supported by Scientific Research Project of Hunan Provincial Department of Education in 2017(17C1603)
文摘[Objectives]To explore the process of simultaneous extracting total flavonoids and chlorogenic acid from Flos Lonicerae by pressure assisted extraction.[Methods]Based on the single factor experiment,orthogonal experiments were carried out to investigate the effects of solvent concentration,solid-to-liquid ratio,extraction pressure,extraction time and extraction temperature on the extraction rate of total flavonoids and chlorogenic acid.[Results]The results showed that the extraction pressure had a significant effect on the extraction of two kinds of chemical constituents from F.Lonicerae.The optimum process conditions were as follows:solvent concentration was 60%,solid-liquid ratio was 1∶20(g/mL),extraction pressure was 2 MPa,extraction time was 30 min,extraction temperature was 70℃.The process conditions are stable,and the extraction efficiency is higher than that of ultrasonic assisted extraction method.Under the test conditions,the extraction rates of total flavonoids and chlorogenic acids were respectively 15.66%and 3.89%.[Conclusions]This study provides a new theoretical basis for the development and utilization of F.Lonicerae.
基金Supported by Guiding Science and Technology Plan Project of Yongzhou City(Yong Ke Fa[2015]10)
文摘[Objectives] This study aimed to optimize the conditions for pressurized synchronous extraction of volatile oils, total flavonoids and tannic acid from Artemisia argyi .[Methods] Single factor experiments and orthogonal experiments were conducted.[Results] Pressurization had a significant effect on the extraction rate of chemical constituents of A. argyi . The optimal conditions for pressurized synchronous extraction of volatile oils, total flavonoids and tannic acid from A. argyi were as follows: solvent concentration of 70%, solid to liquid ratio of 1∶ 30 (g/mL), extraction pressure of 0.9 MPa, extraction time of 40 min and extraction temperature of 90 ℃. Under the optimal extraction conditions, the yields of volatile oils, total flavonoids and tannic acid were 0.852%, 4.66% and 6.79%, respectively.[Conclusions] Compared with other extraction methods, the pressurized assistant solvent extraction method can achieve the synchronous extraction of volatile oils, total flavonoids and tannic acid from A. argyi . The process is stable, short in extraction time, high in solvent utilization rate and ideal in extraction effect of the three components from A. argyi .
基金This paper is the fruit of the key project backed by the 2019 Educational Reform Project of Institution of Higher Education of Shanxi Province(Ideological and Political Theory Course)-A Study on Educational Reform of Ideological and Political Theory Courses in the Big Data Era(Project Number:2019JGSZ003).
文摘Starting from the characteristics of big data,the cognition and thinking of contemporary college students have shown new features.Therefore,it is necessary to use the technical means of big data to formulate thinking under big data,combined with critical thinking.By doing so,students can finally nurture a correct attitude and better morality and even complete the fundamental task of higher education.
基金supported by the National Science and Technology Major Project, China (No. J2019-V-0016-0111)the Aviation Engine and Gas Turbine Basic Science Center Project, China (No. P2022-B-V-003-001)+3 种基金the Defense Industrial Technology Development Program, China (No. JCKY2022607C002)the AECC Industry University Cooperation Project, China (No. HFZL2022CXY013)the National Natural Science Foundation of China (No. 52372396)the Key R&D Project in Shaanxi Province, China (No. 2021GXLH-01-16)。
文摘This paper aims to tackle the calculation efficiency problem raised in the cavitation-flow simulation of the aviation centrifugal pump due to the fading-away interface resulting from the dissipation of numerics used in the phase-change control equation for unstructured-grid multiphase flow,and due to the limitation of flow time-step in whole flow regimes,the control equation of vapor–liquid two-phase flow considering cavitation mass transport is established firstly,modifying the momentum equation by introducing the surface tension,and adding the artificial convective flow to the phase equation to solve the numerical dissipation problem.Secondly,in consideration of the local time step principle and based on the multi-dimensional general limiter algorithm with explicit solutions under the OpenFOAM platform,a solution method of steady-state VOF (Volume of Fluid) model considering cavitation two-phase change is constructed,and the feasibility of this method is verified by NACA hydrofoil and NASA flat plate inducer.Finally,based on the platform developed,the cavitation performance of an aviation centrifugal pump inducer is analyzed.The research results show that the error of the calculated cavitation pressure distribution for NACA hydrofoil between the simulation test and the experimental-test is less than 5%,and the maximum error of calculated cavitation number at pump head dropping for NASA high-speed flat plate inducer between the simulation test and the experimental-test is 2.1%.The cavitation area observed in the simulation test is the same as that obtained in the high-speed photography test.Based on the OpenFOAM simulation method,the position of pump head dropping of the fuel centrifugal pump can be accurately captured.The error of the calculated cavitation number at pump head dropping between the simulation test and the experimental test is about 3.7%,showing high calculation accuracy.
基金partly supported by National Natural Science Foundation of China (Nos. 82074155, 81874436, 81973773, China)“Shuguang Program” supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission (No. 18SG39, China)+5 种基金Program of Shanghai Academic/Technology Research Leader (No. 20XD1423500, China)Clinical Research Plan of SHDC (No. SHDC2020CR3089B, China)Shanghai Key Clinical Specialty Construction Project (No.shslczdzk01201, China)Shanghai Frontier Research Base of Disease and Syndrome Biology of inflammatory cancer transformation (No. 2021KJ03-12, China)Shanghai Sailing Program (No. 20YF1450200, China)Shanghai Collaborative Innovation Center of Industrial Transformation of Hospital TCM Preparation (China)
文摘Nonalcoholic fatty liver disease(NAFLD)is characterized by excessive accumulation of hepatic lipids and metabolic stress-induced liver injury.There are currently no approved effective pharmacological treatments for NAFLD.Traditional Chinese medicine(TCM)has been used for centuries to treat patients with chronic liver diseases without clear disease types and mechanisms.More recently,TCM has been shown to have unique advantages in the treatment of NAFLD.We performed a systematic review of the medical literature published over the last two decades and found that many TCM formulas have been reported to be beneficial for the treatment of metabolic dysfunctions,including Potentilla discolor Bunge(PDB).PDB has a variety of active compounds,including flavonoids,terpenoids,organic acids,steroids and tannins.Many compounds have been shown to exhibit a series of beneficial effects for the treatment of NAFLD,including anti-oxidative and anti-inflammatory functions,improvement of lipid metabolism and reversal of insulin resistance.In this review,we summarize potential therapeutic effects of TCM formulas for the treatment of NAFLD,focusing on the medicinal properties of natural active compounds from PDB and their underlying mechanisms.We point out that PDB can be classified as a novel candidate for the treatment and prevention of NAFLD.
文摘background Intravenous tissue plasminogen activator with or without mechanical thrombectomy during the acute phase are approved therapies for ischaemic stroke.Due to the short treatment time window(<6 hours)and often treatment failure,these patients would still have an intracranial arterial occlusion(IAO).It is unclear whether these patients can benefit from subsequent interventional recanalizationof their occluded artery in the subacute phase.In this retrospective study,we have examined the efficacy and safety in patients who have received either percutaneous transluminal angioplasty(PTA)or percutaneous transluminal angioplasty and stenting(PTAS)for IAO in the subacute phase of their stroke.Methods Patients with subacute symptomatic ischaemic stroke caused by IAO were assessed to identify the responsible artery and low perfusion areas by CT angiography,MR angiography or digital subtraction angiography.In eligible patients,a PTA or PTAS was performed to reopen the occluded artery.Regular antithrombotic therapy,use of statins,control of risk factors and rehabilitation therapy were prescribed after the procedure.All patients had regular follow-up up to 12 months.results PTA or PTAS was performed in 16 patients with cerebral infarction caused by IAO in the subacute phase.After the procedure,12 cases were recanalized,two were partially recanalized and two failed to open.One patient with left C6 segment occlusion of the carotid artery had a central retinal artery embolism after PTAS.The perioperative adverse events were 6.25%.At 3 months,the distribution of modified Rankin scale scores was 0(seven cases),1(three cases),2(five cases)and 3(one case).conclusion Selective PTA or PTAS could be performed in ischaemic stroke patients with a small infarct size and large area of hypoperfusion from an occluded large cerebral artery after the acute phase.It may improve neurological dysfunction and reduce the incidence of disability.
基金We thank constructive suggestions from editors and anonymousreviewers.This research was supported by the NationalKey R&D Plan(No.2018YFC0603801)the Open ResearchProject from the State Key Laboratory of Geological Processesand Mineral Resources,China University of Geosciences(No.GPMR201816)+3 种基金Fundamental Research Funds for the CentralPublic Welfare Research Institutes(Nos.KK1914,KK2013)the National Natural Science Foundation of China(Nos.41911530106,41772084)the Chinese Geological Survey Program(Nos.DD20160055,DD20190379)Key Laboratory ofRegional Geology and Mineralization,Hebei GEO University(No.HGU-RGMKF192).
文摘Large-scale gold mineralization during the Early Cretaceous is identified in the Jiao-dong Peninsula of China.Sources of ore-forming fluids remain debated.We study the Qilishan gold deposit in the northwestern Jiaodong Peninsula with detailed mineralogical observation and in-situ sulfur isotope analyses,in order to reveal the gold occurrence and the origin of ore-forming fluids.The Qilishan gold deposit is mainly clastic altered rock-type in mineralization,and ore minerals are visible native gold,electrum,pyrite,chalcopyrite and galena,gangue minerals as quartz,sericite and calcite.The gold occurrence includes inclusion and intergranular types,formed within pyrites and chalcopy-rites and along their fissures.In-situ sulfur isotope analysis of gold-bearing sulfides suggests that the Qilishan deposit is enriched in heavy sulfur,withδ34S values mainly from+8.0‰to+12.0‰.δ34S val-ues increase gradually with the fluid evolution from the early to late stages,which is interpreted to be related to the loss of sulfur via sulfide precipitation.The crystallization of sulfides from hydrothermal fluids may have triggered the instability of Au(HS)2,and finally led to gold precipitation.Combined with sulfur isotope compositions of other gold deposits(n=43)and wall-rocks in the Jiaodong Peninsu-la,it is proposed that the ore-forming fluids were probably not directly originated from metamorphic wall-rocks(e.g.,Jiaodong Group).Moreover,the relatively long time interval rules out the possibility that the gold mineralization(ca.120 Ma)was associated with granitic magma activities(mostly 160-150 Ma).Possible ore genesis scenario is that,long-term subduction of slabs(e.g.,the Paleo-Pacific)with gold-enriched pyritic materials and crustal sedimentary rocks resulted in both high Au contents and positiveδ34S values of sulfur in the lithospheric mantle below the North China Craton.Subse-quently,devolatilization of the metasomatized mantle produced auriferous fluids that migrated up-ward along translithospheric fault systems,and gold finally precipitated in favorable structural posi-tions,generating the world-class Jiaodong deposits in the Early Cretaceous.
基金supported by the National Natural Science Foundation of China(No.51806010)Shanghai Sailing Program,China(No.18YF1409100).
文摘Mechanically pumped two-phase loop(MPTL)which is a prominent two-phase heat transfer technology presents a promising prospect in thermal control for space payload.However,transient behavior of MPTL caused by phase-change and heat sources load-on/off in simulated space environment is rarely reported.In the present study,one MPTL setup was designed and constructed,and experimentally studied.Particularly,a novel two-phase thermally-controlled accumulator integrated with passive cooling measure and three capillary structures was designed as the temperature-control device.Dynamic behavior of the start-up,temperature control,and temperature adjustment were monitored;meanwhile,thermodynamic behavior within the proposed accumulator,the operating behavior as well as the heat and mass transfer behavior between the main loop and the accumulator were revealed.The results show that the fluid management function of the capillary structures for the novel accumulator is verified.The working point of the MPTL system can be adjusted by changing the temperature control point of the accumulator and it is little influenced by external heat flux and heat sources on/off.Pressure-drop oscillations which are manifested as fluctuations of temperature and pressure can be observed after phase changing due to the compressible volume within the accumulator and the negative-slope portion of the internal pressure.
基金We would like to thank Xing Shen and Yaqing Tang in the Innovative Drug Research Center of Chongqing University and Jing Zhou in the Department of Physiology,Basic Medical College,Peking University,for their support with the work.Thank Zhang San from Shiyanjia Lab(www.shiyanjia.com)for the modulus analysis.This work was supported by the National Key Research and Development Plan Young Scientists Program(No:2017YFA0106000)The National Science Fund for Outstanding Young Scholars(No.31822021)+1 种基金the National Science Foundation of China(No:31771057)and The National Key Research and Development Plan(No:2016YFC1101100).
文摘Small-diameter tissue-engineered vascular grafts(sdTEVGs)with hyperglycemia resistance have not been constructed.The intimal hyperplasia caused by hyperglycemia remains problem to hinder the patency of sdTEVGs.Here,inspired by bionic regulation of nerve on vascular,we found the released neural exosomes could inhibit the abnormal phenotype transformation of vascular smooth muscle cells(VSMCs).The transformation was a prime culprit causing the intimal hyperplasia of sdTEVGs.To address this concern,sdTEVGs were modified with an on-demand programmable dual-responsive system of ultrathin hydrogels.An external primary Reactive Oxygen Species(ROS)-responsive Netrin-1 system was initially triggered by local inflammation to induce nerve remolding of the sdTEVGs overcoming the difficulty of nerve regeneration under hyperglycemia.Then,the internal secondary ATP-responsive DENND1A(guanine nucleotide exchange factor)system was turned on by the neurotransmitter ATP from the immigrated nerve fibers to stimulate effective release of neural exosomes.The results showed nerve fibers grow into the sdTEVGs in diabetic rats 30 days after transplantation.At day 90,the abnormal VSMCs phenotype was not detected in the sdTEVGs,which maintained long-time patency without intima hyperplasia.Our study provides new insights to construct vascular grafts resisting hyperglycemia damage.
基金This research was partially the National Natural Science Foundation of China under grants 11525103 and 91130004.
文摘An adaptive multi-penalty discontinuous Galerkin method(AMPDG)for the diffusion problem is considered.Convergence and quasi-optimality of the AM-PDG are proved.Compared with the analyses for the adaptive finite element method or the adaptive interior penalty discontinuous Galerkin method,extra works are done to overcome the difficulties caused by the additional penalty terms.
