Conventional PI control encounters some problems when dealing with large lag process in the presence of parameter uncertainties.For the typical first-order process,an observerbased linear active disturbance rejection ...Conventional PI control encounters some problems when dealing with large lag process in the presence of parameter uncertainties.For the typical first-order process,an observerbased linear active disturbance rejection control(LADRC)scheme is presented to cope with the difficulties,and a reduced-order observer scheme is proposed further.Some quantitative dynamic results with regard to non-overshoot characteristics are obtained.Finally,the performance boundaries of LADRC and PI control are explicitly compared with each other,which shows that the former is more superior in most cases.展开更多
The high-purity distillation column system is strongly nonlinear and coupled,which makes it difficult to control.Active disturbance rejection control(ADRC)has been widely used in distillation systems,but it has limita...The high-purity distillation column system is strongly nonlinear and coupled,which makes it difficult to control.Active disturbance rejection control(ADRC)has been widely used in distillation systems,but it has limitations in controlling distillation systems with large time delays since ADRC employs ESO and feedback control law to estimate the total disturbance of the system without considering the large time delays.This paper designs a proportion integral-type active disturbance rejection generalized predictive control(PI-ADRGPC)algorithm to control the distillation column system with large time delay.It replaces the PD controller in ADRC with a proportion integral-type generalized predictive control(PI-GPC),thereby improving the performance of control systems with large time delays.Since the proposed controller has many parameters and is difficult to tune,this paper proposes to use the grey wolf optimization(GWO)to tune these parameters,whose structure can also be used by other intelligent optimization algorithms.The performance of GWO tuned PI-ADRGPC is compared with the control performance of GWO tuned ADRC method,multi-verse optimizer(MVO)tuned PI-ADRGPC and MVO tuned ADRC.The simulation results show that the proposed strategy can track reference well and has a good disturbance rejection performance.展开更多
Evaluation of calligraphic copy is the core of Chinese calligraphy appreciation and in-heritance.However,previous aesthetic evaluation studies often focussed on photos and paintings,with few attempts on Chinese callig...Evaluation of calligraphic copy is the core of Chinese calligraphy appreciation and in-heritance.However,previous aesthetic evaluation studies often focussed on photos and paintings,with few attempts on Chinese calligraphy.To solve this problem,a Siamese regression aesthetic fusion method is proposed,named SRAFE,for Chinese calligraphy based on the combination of calligraphy aesthetics and deep learning.First,a dataset termed Evaluated Chinese Calligraphy Copies(E3C)is constructed for aesthetic evalu-ation.Second,12 hand‐crafted aesthetic features based on the shape,structure,and stroke of calligraphy are designed.Then,the Siamese regression network(SRN)is designed to extract the deep aesthetic representation of calligraphy.Finally,the SRAFE method is built by fusing the deep aesthetic features with the hand‐crafted aesthetic features.Experimental results show that scores given by SRAFE are similar to the aesthetic evaluation label of E3C,proving the effectiveness of the authors’method.展开更多
Background Pediatric acute fulminant myocarditis(AFM)is a very dangerous disease that may lead to acute heart failure or even sudden death.Previous reports have identified some prognostic factors in adult AFM;however,...Background Pediatric acute fulminant myocarditis(AFM)is a very dangerous disease that may lead to acute heart failure or even sudden death.Previous reports have identified some prognostic factors in adult AFM;however,there is no such research on children with AFM on venoarterial extracorporeal membrane oxygenation(VA-ECMO).This study aimed to find relevant prognostic factors for predicting adverse clinical outcomes.Methods A retrospective analysis was performed in an affiliated university children’s hospital with consecutive patients receiving VA-ECMO for AFM from July 2010 to November 2020.These children were classified into a survivor group(n=33)and a non-survivor group(n=8).Patient demographics,clinical events,laboratory findings,and electrocardiographic and echocardiographic parameters were analyzed.Results Peak serum creatinine(SCr)and peak creatine kinase isoenzyme MB during ECMO had joint predictive value for in-hospital mortality(p=0.011,AUC=0.962).Based on multivariable logistic regression analysis,peak SCr level during ECMO support was an independent predictor of in-hospital mortality(OR=1.035,95%CI 1.006 to 1.064,p=0.017,AUC=0.936,with optimal cut-off value of 78μmol/L).Conclusion Tissue hypoperfusion and consequent end-organ damage ultimately hampered the outcomes.The need for left atrial decompression indicated a sicker patient on ECMO and introduced additional risk for complications.Earlier and more cautious deployment would likely be associated with decreased risk of complications and mortality.展开更多
Background:We aimed to systematically review the efficacy of mannitol(MTL)on patients with acute severe traumatic brain injury(TBI).Methods:Databases such as PubMed(US National Library of Medicine),CENTRAL(The Cochran...Background:We aimed to systematically review the efficacy of mannitol(MTL)on patients with acute severe traumatic brain injury(TBI).Methods:Databases such as PubMed(US National Library of Medicine),CENTRAL(The Cochrane Library 2014,Issue 3),ISI(Web of Science:Science Citation Index Expanded),Chinese Biomedicine Database(CBM),and China Knowledge Resource Integrated Database(CNKI)have been searched for relevant studies published between 1 January 2003 and 1 October 2014.We have established inclusion and exclusion criteria to identify RCTs,which were suitable to be enrolled in the systematic review.The comparison group could be hypertonic saline(HS),hydroxyethyl starch,or others.The quality assessment was based on the Cochrane Handbook for Systematic Reviews of Interventions Version 5.0.1 and modified Jadad score scale.The major outcome was mortality,followed by the secondary outcomes such as neurological outcome,days on intensive care unit(ICU),and ventilator day.In addition,intracranial pressure(ICP),cerebral perfusion pressure(CPP),and mean arterial pressure(MAP)were used as the surrogate endpoints.Data synthesis and meta-analysis was conducted by using R(version 3.7-0.).Results:When 176 potential relevant literatures and abstracts have been screened,four RCTs met all the inclusion criteria and were enrolled for the meta-analysis.Amongst all the enrolled studies,two trials have provided the primary outcome data.There was no heterogeneity between two studies(I2=0%)and a fixed model was used for meta-analysis(n=53),pooled result indicated that the mortality was similar in mannitol intervention and control treatment,OR=0.80,95%CI[0.27,2.37],P=0.38.We found that both mannitol and HS were efficient in decreasing the ICP.Furthermore,the effect of the HS on the ICP appeared to be more effective in the patients with diffuse brain injuries than mannitol did.Conclusions:As a conclusion,the mannitol therapy cannot reduce the mortality risk of acute severe traumatic brain injury.Current evidence does not support the mannitol as an effective treatment of acute severe traumatic brain injury.The well-designed randomized controlled trials are in urgent need to demonstrate the adoption of mannitol to acute severe traumatic brain injury.展开更多
What is already known about this topic?Allergic diseases have affected an estimated 40%of the population in China.However,our understanding of the full spectrum of these diseases remains insufficient.What is added by ...What is already known about this topic?Allergic diseases have affected an estimated 40%of the population in China.However,our understanding of the full spectrum of these diseases remains insufficient.What is added by this report?Between 2018 and 2021,Yichang City documented 625,929 outpatient visits mainly related to skin and mucous membrane allergies(77.90%)and allergic respiratory conditions(19.64%).In 2021,the occurrence of outpatient visits for conditions such as allergic rhinitis,acute atopic conjunctivitis,and atopic dermatitis increased.The demographic analysis revealed that male patients comprised the majority of the under 18 age bracket(56.05%),while female patients were predominantly represented in the 18 to 65 age bracket(61.79%).What are the implications for public health practice?This constitutes the first analysis of the spectrum of allergic diseases,utilizing regional outpatient data,which has substantial implications for understanding the disease burden.展开更多
Background and Objectives:We aim to establish deep learning models to optimize the individualized energy delivery for septic patients.Methods and Study Design:We conducted a study of adult septic patients in ICU,colle...Background and Objectives:We aim to establish deep learning models to optimize the individualized energy delivery for septic patients.Methods and Study Design:We conducted a study of adult septic patients in ICU,collecting 47 indicators for 14 days.We filtered out nutrition-related features and divided the data into datasets according to the three metabolic phases proposed by ESPEN:acute early,acute late,and rehabilitation.We then established optimal energy target models for each phase using deep learning and conducted external validation.Results:A total of 179 patients in training dataset and 98 patients in external validation dataset were included in this study,and total data size was 3115 elements.The age,weight and BMI of the patients were 63.05(95%CI 60.42-65.68),61.31(95%CI 59.62-63.00)and 22.70(95%CI 22.21-23.19),respectively.And 26.0%(72)of the patients were female.The models indicated that the optimal energy targets in the three phases were 900kcal/d,2300kcal/d,and 2000kcal/d,respectively.Excessive energy intake increased mortality rapidly in the early period of the acute phase.Insufficient energy in the late period of the acute phase significantly raised the mortality as well.For the rehabilitation phase,too much or too little energy delivery were both associated with elevated death risk.Conclusions:Our study established time-series prediction models for septic patients to optimize energy delivery in the ICU.We recommended permissive underfeeding only in the early acute phase.Later,increased energy intake may improve survival and settle energy debts caused by underfeeding.展开更多
The major histocompatibility complex(MHC)of proteins that exists in all vertebrates is encoded by a cluster of genes associated with the immune response and related functions.MHC is divided into MHC I,II,and III;MHC I...The major histocompatibility complex(MHC)of proteins that exists in all vertebrates is encoded by a cluster of genes associated with the immune response and related functions.MHC is divided into MHC I,II,and III;MHC I is involved in antigenic presentation,binding T cell receptors,and leading ultimately to specific cellular immune responses.The complicated functions of MHC I are determined by the nature of the complex.The crystal structure of MHC I has been solved for many animals,revealing the relationship between spatial structure and function.MHC I consists of an a heavy chain and a b2m light chain,both ligated non-covalently to a complex when a peptide is bound to the antigenic-binding groove.The a heavy chain is divided into an extracellular domain,a transmembrane domain,and an intracellular domain.The extracellular domain consists of sub-regions a1,a2,and a3.The a1 and a2 together form the antigenic-binding groove and bind antigenic peptides with 8–10 amino acid residues.MHC I can form a stable spatial structure;however,it should be noted that there are differences in the structure of MHC I among animal species,including anchored amino acids in binding peptides,binding sites,molecular distance,crystallization conditions,etc.Here,progress in determination of the crystal structure of human,mouse,chicken,non-human primate,and swine MHC I is described in detail.展开更多
The mysteries of life’s evolution on our planet drive us to explore the limits of biology.Life forms on Earth as we know are composed of six essential elements:carbon,hydrogen,oxygen,nitrogen,sulfur and phosphorus.Ho...The mysteries of life’s evolution on our planet drive us to explore the limits of biology.Life forms on Earth as we know are composed of six essential elements:carbon,hydrogen,oxygen,nitrogen,sulfur and phosphorus.However,a recently published research work funded by the National Aeronautics and Space Administration(NASA),USA,has almost shaken the fundamental knowledge about what is life made of on Earth.The research team led by NASA astrobiologist Felisa Wolfe-Simon described a microbe isolated from California’s Mono Lake that could sustain its growth by using toxic chemical arsenic(As)instead of phosphorus(P).This surprising discovery was published online by Science Express on December 2 last year(Wolfe-Simon et al.,2010,online).If the authors of the paper were right,we would have to expand our definition of life on this planet.The arsenic-bug they grew was dubbed GFAJ-1,which interestingly stands for“Give Felisa A Job.”展开更多
基金supported by the National Natural Science Foundation of China(60774088)the National High Technology Research and Development Program of China(863 Program)(2009AA04Z132)the Specialized Research Fund for the Doctoral Program of Higher Education of China(20090031110029)
文摘Conventional PI control encounters some problems when dealing with large lag process in the presence of parameter uncertainties.For the typical first-order process,an observerbased linear active disturbance rejection control(LADRC)scheme is presented to cope with the difficulties,and a reduced-order observer scheme is proposed further.Some quantitative dynamic results with regard to non-overshoot characteristics are obtained.Finally,the performance boundaries of LADRC and PI control are explicitly compared with each other,which shows that the former is more superior in most cases.
基金funded by the National Natural Science Foundation of China(61973175,62073177 and 61973172)South African National Research Foundation(132797)+2 种基金South African National Research Foundation Incentive(114911)Eskom Tertiary Education Support Programme Grant of South AfricaTianjin Research Innovation Project for Postgraduate Students(2021YJSB018,2020YJSB003)。
文摘The high-purity distillation column system is strongly nonlinear and coupled,which makes it difficult to control.Active disturbance rejection control(ADRC)has been widely used in distillation systems,but it has limitations in controlling distillation systems with large time delays since ADRC employs ESO and feedback control law to estimate the total disturbance of the system without considering the large time delays.This paper designs a proportion integral-type active disturbance rejection generalized predictive control(PI-ADRGPC)algorithm to control the distillation column system with large time delay.It replaces the PD controller in ADRC with a proportion integral-type generalized predictive control(PI-GPC),thereby improving the performance of control systems with large time delays.Since the proposed controller has many parameters and is difficult to tune,this paper proposes to use the grey wolf optimization(GWO)to tune these parameters,whose structure can also be used by other intelligent optimization algorithms.The performance of GWO tuned PI-ADRGPC is compared with the control performance of GWO tuned ADRC method,multi-verse optimizer(MVO)tuned PI-ADRGPC and MVO tuned ADRC.The simulation results show that the proposed strategy can track reference well and has a good disturbance rejection performance.
文摘Evaluation of calligraphic copy is the core of Chinese calligraphy appreciation and in-heritance.However,previous aesthetic evaluation studies often focussed on photos and paintings,with few attempts on Chinese calligraphy.To solve this problem,a Siamese regression aesthetic fusion method is proposed,named SRAFE,for Chinese calligraphy based on the combination of calligraphy aesthetics and deep learning.First,a dataset termed Evaluated Chinese Calligraphy Copies(E3C)is constructed for aesthetic evalu-ation.Second,12 hand‐crafted aesthetic features based on the shape,structure,and stroke of calligraphy are designed.Then,the Siamese regression network(SRN)is designed to extract the deep aesthetic representation of calligraphy.Finally,the SRAFE method is built by fusing the deep aesthetic features with the hand‐crafted aesthetic features.Experimental results show that scores given by SRAFE are similar to the aesthetic evaluation label of E3C,proving the effectiveness of the authors’method.
基金This work was financially support by the Scientific Research Program of Shanghai Maternal and Child Health Association(ZGMF-B 201908).
文摘Background Pediatric acute fulminant myocarditis(AFM)is a very dangerous disease that may lead to acute heart failure or even sudden death.Previous reports have identified some prognostic factors in adult AFM;however,there is no such research on children with AFM on venoarterial extracorporeal membrane oxygenation(VA-ECMO).This study aimed to find relevant prognostic factors for predicting adverse clinical outcomes.Methods A retrospective analysis was performed in an affiliated university children’s hospital with consecutive patients receiving VA-ECMO for AFM from July 2010 to November 2020.These children were classified into a survivor group(n=33)and a non-survivor group(n=8).Patient demographics,clinical events,laboratory findings,and electrocardiographic and echocardiographic parameters were analyzed.Results Peak serum creatinine(SCr)and peak creatine kinase isoenzyme MB during ECMO had joint predictive value for in-hospital mortality(p=0.011,AUC=0.962).Based on multivariable logistic regression analysis,peak SCr level during ECMO support was an independent predictor of in-hospital mortality(OR=1.035,95%CI 1.006 to 1.064,p=0.017,AUC=0.936,with optimal cut-off value of 78μmol/L).Conclusion Tissue hypoperfusion and consequent end-organ damage ultimately hampered the outcomes.The need for left atrial decompression indicated a sicker patient on ECMO and introduced additional risk for complications.Earlier and more cautious deployment would likely be associated with decreased risk of complications and mortality.
基金grants from Sichuan Provincial Department of Science and Technology(2012SZ0181,SZ20120209)grants from Chengdu Municipality Department of Science and Technology(11PPYB099SF-289 AND 12PPYB181SF-002).
文摘Background:We aimed to systematically review the efficacy of mannitol(MTL)on patients with acute severe traumatic brain injury(TBI).Methods:Databases such as PubMed(US National Library of Medicine),CENTRAL(The Cochrane Library 2014,Issue 3),ISI(Web of Science:Science Citation Index Expanded),Chinese Biomedicine Database(CBM),and China Knowledge Resource Integrated Database(CNKI)have been searched for relevant studies published between 1 January 2003 and 1 October 2014.We have established inclusion and exclusion criteria to identify RCTs,which were suitable to be enrolled in the systematic review.The comparison group could be hypertonic saline(HS),hydroxyethyl starch,or others.The quality assessment was based on the Cochrane Handbook for Systematic Reviews of Interventions Version 5.0.1 and modified Jadad score scale.The major outcome was mortality,followed by the secondary outcomes such as neurological outcome,days on intensive care unit(ICU),and ventilator day.In addition,intracranial pressure(ICP),cerebral perfusion pressure(CPP),and mean arterial pressure(MAP)were used as the surrogate endpoints.Data synthesis and meta-analysis was conducted by using R(version 3.7-0.).Results:When 176 potential relevant literatures and abstracts have been screened,four RCTs met all the inclusion criteria and were enrolled for the meta-analysis.Amongst all the enrolled studies,two trials have provided the primary outcome data.There was no heterogeneity between two studies(I2=0%)and a fixed model was used for meta-analysis(n=53),pooled result indicated that the mortality was similar in mannitol intervention and control treatment,OR=0.80,95%CI[0.27,2.37],P=0.38.We found that both mannitol and HS were efficient in decreasing the ICP.Furthermore,the effect of the HS on the ICP appeared to be more effective in the patients with diffuse brain injuries than mannitol did.Conclusions:As a conclusion,the mannitol therapy cannot reduce the mortality risk of acute severe traumatic brain injury.Current evidence does not support the mannitol as an effective treatment of acute severe traumatic brain injury.The well-designed randomized controlled trials are in urgent need to demonstrate the adoption of mannitol to acute severe traumatic brain injury.
文摘What is already known about this topic?Allergic diseases have affected an estimated 40%of the population in China.However,our understanding of the full spectrum of these diseases remains insufficient.What is added by this report?Between 2018 and 2021,Yichang City documented 625,929 outpatient visits mainly related to skin and mucous membrane allergies(77.90%)and allergic respiratory conditions(19.64%).In 2021,the occurrence of outpatient visits for conditions such as allergic rhinitis,acute atopic conjunctivitis,and atopic dermatitis increased.The demographic analysis revealed that male patients comprised the majority of the under 18 age bracket(56.05%),while female patients were predominantly represented in the 18 to 65 age bracket(61.79%).What are the implications for public health practice?This constitutes the first analysis of the spectrum of allergic diseases,utilizing regional outpatient data,which has substantial implications for understanding the disease burden.
基金supported by Sichuan Science and Technology Program(No.2021YFH0109 to Mingwei Sun and 2021YFS0378 to Hua Jiang)National Natural Science Foundation of China(No.72074222 to Wei Chen).
文摘Background and Objectives:We aim to establish deep learning models to optimize the individualized energy delivery for septic patients.Methods and Study Design:We conducted a study of adult septic patients in ICU,collecting 47 indicators for 14 days.We filtered out nutrition-related features and divided the data into datasets according to the three metabolic phases proposed by ESPEN:acute early,acute late,and rehabilitation.We then established optimal energy target models for each phase using deep learning and conducted external validation.Results:A total of 179 patients in training dataset and 98 patients in external validation dataset were included in this study,and total data size was 3115 elements.The age,weight and BMI of the patients were 63.05(95%CI 60.42-65.68),61.31(95%CI 59.62-63.00)and 22.70(95%CI 22.21-23.19),respectively.And 26.0%(72)of the patients were female.The models indicated that the optimal energy targets in the three phases were 900kcal/d,2300kcal/d,and 2000kcal/d,respectively.Excessive energy intake increased mortality rapidly in the early period of the acute phase.Insufficient energy in the late period of the acute phase significantly raised the mortality as well.For the rehabilitation phase,too much or too little energy delivery were both associated with elevated death risk.Conclusions:Our study established time-series prediction models for septic patients to optimize energy delivery in the ICU.We recommended permissive underfeeding only in the early acute phase.Later,increased energy intake may improve survival and settle energy debts caused by underfeeding.
基金supported by the National Natural Science Foundation of China(30972169 and 31172304)the Liaoning Doctoral Start Fund(20081078)the Liaoning Scientific Project in Education Bureau(L2010018)
文摘The major histocompatibility complex(MHC)of proteins that exists in all vertebrates is encoded by a cluster of genes associated with the immune response and related functions.MHC is divided into MHC I,II,and III;MHC I is involved in antigenic presentation,binding T cell receptors,and leading ultimately to specific cellular immune responses.The complicated functions of MHC I are determined by the nature of the complex.The crystal structure of MHC I has been solved for many animals,revealing the relationship between spatial structure and function.MHC I consists of an a heavy chain and a b2m light chain,both ligated non-covalently to a complex when a peptide is bound to the antigenic-binding groove.The a heavy chain is divided into an extracellular domain,a transmembrane domain,and an intracellular domain.The extracellular domain consists of sub-regions a1,a2,and a3.The a1 and a2 together form the antigenic-binding groove and bind antigenic peptides with 8–10 amino acid residues.MHC I can form a stable spatial structure;however,it should be noted that there are differences in the structure of MHC I among animal species,including anchored amino acids in binding peptides,binding sites,molecular distance,crystallization conditions,etc.Here,progress in determination of the crystal structure of human,mouse,chicken,non-human primate,and swine MHC I is described in detail.
文摘The mysteries of life’s evolution on our planet drive us to explore the limits of biology.Life forms on Earth as we know are composed of six essential elements:carbon,hydrogen,oxygen,nitrogen,sulfur and phosphorus.However,a recently published research work funded by the National Aeronautics and Space Administration(NASA),USA,has almost shaken the fundamental knowledge about what is life made of on Earth.The research team led by NASA astrobiologist Felisa Wolfe-Simon described a microbe isolated from California’s Mono Lake that could sustain its growth by using toxic chemical arsenic(As)instead of phosphorus(P).This surprising discovery was published online by Science Express on December 2 last year(Wolfe-Simon et al.,2010,online).If the authors of the paper were right,we would have to expand our definition of life on this planet.The arsenic-bug they grew was dubbed GFAJ-1,which interestingly stands for“Give Felisa A Job.”
