Owing to their global search capabilities and gradient-free operation,metaheuristic algorithms are widely applied to a wide range of optimization problems.However,their computational demands become prohibitive when ta...Owing to their global search capabilities and gradient-free operation,metaheuristic algorithms are widely applied to a wide range of optimization problems.However,their computational demands become prohibitive when tackling high-dimensional optimization challenges.To effectively address these challenges,this study introduces cooperative metaheuristics integrating dynamic dimension reduction(DR).Building upon particle swarm optimization(PSO)and differential evolution(DE),the proposed cooperative methods C-PSO and C-DE are developed.In the proposed methods,the modified principal components analysis(PCA)is utilized to reduce the dimension of design variables,thereby decreasing computational costs.The dynamic DR strategy implements periodic execution of modified PCA after a fixed number of iterations,resulting in the important dimensions being dynamically identified.Compared with the static one,the dynamic DR strategy can achieve precise identification of important dimensions,thereby enabling accelerated convergence toward optimal solutions.Furthermore,the influence of cumulative contribution rate thresholds on optimization problems with different dimensions is investigated.Metaheuristic algorithms(PSO,DE)and cooperative metaheuristics(C-PSO,C-DE)are examined by 15 benchmark functions and two engineering design problems(speed reducer and composite pressure vessel).Comparative results demonstrate that the cooperative methods achieve significantly superior performance compared to standard methods in both solution accuracy and computational efficiency.Compared to standard metaheuristic algorithms,cooperative metaheuristics achieve a reduction in computational cost of at least 40%.The cooperative metaheuristics can be effectively used to tackle both high-dimensional unconstrained and constrained optimization problems.展开更多
In practical engineering, many uncertain factors in loading or degradation of material properties may vary with time. Stochastic process modeling constitutes a suitable approach for describing these time-dependent unc...In practical engineering, many uncertain factors in loading or degradation of material properties may vary with time. Stochastic process modeling constitutes a suitable approach for describing these time-dependent uncertainties. By adopting this approach, however, the timedependent reliability calculation is a great challenge owing to the complexity and the huge computational burden. This paper presents a new instantaneous response surface method t-IRS for time-dependent reliability analysis. Different from the adaptive extreme response surface approach, the proposed method does not need to build and update surrogate models separately at each time node. It first uses the expansion optimal linear estimation method to discretize the stochastic processes into a set of independent standard normal variables together with some deterministic functions of time. Time is then treated as an independent one-dimensional variable. Next, initial samples are generated by Latin hypercube sampling, and the corresponding response values are calculated and utilized to construct an instantaneous response surrogate model of the Kriging type. The active learning method is applied to update the Kriging surrogate model until satisfactory accuracy is achieved. Finally, the instantaneous response surrogate model is used to compute the time-dependent reliability via Monte Carlo simulation. Four case studies are utilized to demonstrate the effectiveness of the ^-IRS method for time-dependent reliability analysis.展开更多
Objective:To uncover the underlying mechanism of Hewei Jiangni granule(HWJNG)on non-erosive reflux disease(NERD)treatment by examining histological changes,gastrointestinal neurochemicals release and visceral hypersen...Objective:To uncover the underlying mechanism of Hewei Jiangni granule(HWJNG)on non-erosive reflux disease(NERD)treatment by examining histological changes,gastrointestinal neurochemicals release and visceral hypersensitivity-related receptor expression in NERD model rats.Methods:A NERD rat model was established via a combination of basal sensitization and acid perfusion.HWJNG treatments at different doses were then administered.Pathological changes to tissues,mast cell(MC)activation,serum levels of esophageal visceral hypersensitivity-related neurochemicals,and transient receptor potential(TRP)receptor mRNA and protein levels were investigated.Results:Compared with the control group,the expression of tryptase in MCs,the changes of intercellular space,and the serum levels of substance P(SP),calcitonin gene-related peptides(CGRP)and proteinaseactivated receptor 2(PAR2)increased in the model group(all P<.05).The expression of TRP vanilloid 1(Trpv1)mRNA decreased in esophagus and dorsal root ganglia(DRG)of the model group(P=.030&P=.013),and the expression of TRP melastatin channel subfamily member 8(Trpm8)mRNA decreased in the esophagus of model group(P<.01).The level of esophageal TRPV1 protein increased in the model group(P<.01)and the level of TRPM8 protein decreased in esophagus and DRG of the model group(both P<.05).Compared with the model group,the serum levels of SP,CGRP,and PAR2 in the mediumdose HWJNG group showed significant decreases(all P<.05).The expression of Trpv1 mRNA in esophagus and DRG of the HWJNG groups and the Omeprazole group remarkably decreased(all P<.05),as was the expression of Trpm8 mRNA in esophagus of the HWJNG groups(all P<.05).Conclusion:HWJNG alleviated visceral hypersensitivity in NERD model rats by regulating TRP-mediated signaling.Our results indicate that HWJNG has potential as a therapeutic agent for NERD.展开更多
Over the last decade,the rapid advances of life sciences have significantly increased public awareness and comprehension of dermatological knowledge,resulting in widespread acceptance of scientific skincare in society...Over the last decade,the rapid advances of life sciences have significantly increased public awareness and comprehension of dermatological knowledge,resulting in widespread acceptance of scientific skincare in society.The scope of photoprotection has expanded to encompass not only ultraviolet radiation but also visible light(including blue light).Furthermore,photoprotection methods have evolved from light blocking to the repair of cellular damage caused by prolonged light exposure via biological signaling pathways.Blue light(BL)is the portion of sunlight between 400 nm(violet)and 500 nm(cyan),that can penetrate deep into biological tissues,with up to 20%reaching subcutaneous tissues.Similar to UV damage,BL can cause oxidative stress,persistent pigmentation,and extracellular matrix degradation,resulting in skin symptoms such as hyperpigmentation,dullness,lack of radiance,uneven skin tone,and wrinkles.This study investigates the clinical manifestations of BL-induced skin photodamages,as well as the underlying biological mechanisms and proposes rational photoaging prevention strategies.展开更多
Multistage multi-cluster hydraulic fracturing has enabled the economic exploitation of shale reservoirs,but the interpretation of hydraulic fracture parameters is challenging.The pressure signals after pump shutdown a...Multistage multi-cluster hydraulic fracturing has enabled the economic exploitation of shale reservoirs,but the interpretation of hydraulic fracture parameters is challenging.The pressure signals after pump shutdown are influenced by hydraulic fractures,which can reflect the geometric features of hydraulic fracture.The shutdown pressure can be used to interpret the hydraulic fracture parameters in a real-time and cost-effective manner.In this paper,a mathematical model for shutdown pressure evolution is developed considering the effects of wellbore friction,perforation friction and fluid loss in fractures.An efficient numerical simulation method is established by using the method of characteristics.Based on this method,the impacts of fracture half-length,fracture height,opened cluster and perforation number,and filtration coefficient on the evolution of shutdown pressure are analyzed.The results indicate that a larger fracture half-length may hasten the decay of shutdown pressure,while a larger fracture height can slow down the decay of shutdown pressure.A smaller number of opened clusters and perforations can significantly increase the perforation friction and decrease the overall level of shutdown pressure.A larger filtration coefficient may accelerate the fluid filtration in the fracture and hasten the drop of the shutdown pressure.The simulation method of shutdown pressure,as well as the analysis results,has important implications for the interpretation of hydraulic fracture parameters.展开更多
Adult central nervous system （CNS） tissue has a limited capacity to recover after trauma or disease. Recent medical cell therapy using polymeric biomaterial- loaded stem cells with the capability of differentiation ...Adult central nervous system （CNS） tissue has a limited capacity to recover after trauma or disease. Recent medical cell therapy using polymeric biomaterial- loaded stem cells with the capability of differentiation to specific neural population has directed focuses toward the recovery of CNS. Fibers that can provide topographical, biochemical and electrical cues would be attractive for directing the differentiation of stem cells into electro-responsive cells such as neuronal cells. Here we report on the fabrication of an electrospun polypyrrole/polylactide composite nanofiber film that direct or determine the fate of mesenchymal stem cells （MSCs）, via combination of aligned surface topography, and electrical stimulation （ES）. The surface morphology, mechanical properties and electric properties of the film were characterized. Comparing with that on random surface film, expression of neurofilament-lowest and nestin of human umbilical cord mesenchymal stem cells （huMSCs） cultured on film with aligned surface topography and ES were obviously enhanced. These results suggest that aligned topography combining with ES facilitates the neurogenic differentiation of huMSCs and the aligned conductive film can act as a potential nerve scaffold.展开更多
Background:Histological healing is closely associated with improved long-term clinical outcomes and lowered relapses in patients with ulcerative colitis(UC).Here,we developed a novel diagnostic criterion for assessing...Background:Histological healing is closely associated with improved long-term clinical outcomes and lowered relapses in patients with ulcerative colitis(UC).Here,we developed a novel diagnostic criterion for assessing histological healing in UC patients.Methods:We conducted a retrospective cohort study in UC patients,whose treatment was iteratively optimized to achieve mucosal healing at Shanghai Tenth People’s Hospital of Tongji University from January 2017 to May 2022.We identified an inflammatory cell enumeration index(ICEI)for assessing histological healing based on the proportions of eosinophils,CD177^(+)neutrophils,and CD40L^(+)T cells in the colonic lamina propria under high power field(HPF),and the outcomes(risks of symptomatic relapses)of achieving histological remission vs.persistent histological inflammation using Kaplan-Meier curves.Intrareader reliability and inter-reader reliability were evaluated by each reader.The relationships to the changes in the Nancy index and the Geboes score were also assessed for responsiveness.The ICEI was further validated in a new cohort of UC patients from other nine university hospitals.Results:We developed an ICEI for clinical diagnosis of histological healing,i.e.,Y=1.701X_(1)+0.758X_(2)+1.347X_(3)-7.745(X_(1),X_(2),and X_(3)represent the proportions of CD177^(+)neutrophils,eosinophils,and CD40L^(+)T cells,respectively,in the colonic lamina propria under HPF).The receiver operating characteristics curve(ROC)analysis revealed that Y<-0.391 was the cutoff value for the diagnosis of histological healing and that an area under the curve(AUC)was 0.942(95%confidence interval[CI]:0.905-0.979)with a sensitivity of 92.5%and a specificity of 83.6%(P<0.001).The intraclass correlation coefficient(ICC)for the intrareader reliability was 0.855(95%CI:0.781-0.909),and ICEI had good inter-reader reliability of 0.832(95%CI:0.748-0.894).During an 18-month follow-up,patients with histological healing had a substantially better outcome compared with those with unachieved histological healing(P<0.001)using ICEI.During a 12-month follow-up from other nine hospitals,patients with histological healing also had a lower risk of relapse than patients with unachieved histological healing.Conclusions:ICEI can be used to predict histological healing and identify patients with a risk of relapse 12 months and 18 months after clinical therapy.Therefore,ICEI provides a promising,simplified approach to monitor histological healing and to predict the prognosis of UC.Registration:Chinese Clinical Trial Registry,No.ChiCTR2300077792.展开更多
The Tibetan Plateau (TP) encompasses Xizang and Qinghai and parts of northern Yunnan and Sichuan provinces, with a total area of circa 2.6 millions km2. The 2013 satellite data showed that grasslands, forests, wetland...The Tibetan Plateau (TP) encompasses Xizang and Qinghai and parts of northern Yunnan and Sichuan provinces, with a total area of circa 2.6 millions km2. The 2013 satellite data showed that grasslands, forests, wetlands, agricultural lands, and deserts account for 60%, 7.7%, 1.4%, 0.3%, and 30%, respectively, of total TP land (1)Due to its existence in dry, high altitude and cold environments, the TP ecosystem is extremely vulnerable to global climate change and studies on the TP ecosystem can be utilized as a pre-warning for other ecosystems.展开更多
基金funded by National Natural Science Foundation of China(Nos.12402142,11832013 and 11572134)Natural Science Foundation of Hubei Province(No.2024AFB235)+1 种基金Hubei Provincial Department of Education Science and Technology Research Project(No.Q20221714)the Opening Foundation of Hubei Key Laboratory of Digital Textile Equipment(Nos.DTL2023019 and DTL2022012).
文摘Owing to their global search capabilities and gradient-free operation,metaheuristic algorithms are widely applied to a wide range of optimization problems.However,their computational demands become prohibitive when tackling high-dimensional optimization challenges.To effectively address these challenges,this study introduces cooperative metaheuristics integrating dynamic dimension reduction(DR).Building upon particle swarm optimization(PSO)and differential evolution(DE),the proposed cooperative methods C-PSO and C-DE are developed.In the proposed methods,the modified principal components analysis(PCA)is utilized to reduce the dimension of design variables,thereby decreasing computational costs.The dynamic DR strategy implements periodic execution of modified PCA after a fixed number of iterations,resulting in the important dimensions being dynamically identified.Compared with the static one,the dynamic DR strategy can achieve precise identification of important dimensions,thereby enabling accelerated convergence toward optimal solutions.Furthermore,the influence of cumulative contribution rate thresholds on optimization problems with different dimensions is investigated.Metaheuristic algorithms(PSO,DE)and cooperative metaheuristics(C-PSO,C-DE)are examined by 15 benchmark functions and two engineering design problems(speed reducer and composite pressure vessel).Comparative results demonstrate that the cooperative methods achieve significantly superior performance compared to standard methods in both solution accuracy and computational efficiency.Compared to standard metaheuristic algorithms,cooperative metaheuristics achieve a reduction in computational cost of at least 40%.The cooperative metaheuristics can be effectively used to tackle both high-dimensional unconstrained and constrained optimization problems.
基金supported by the National Natural Science Foundation of China (Nos.11572134 and 11832013).
文摘In practical engineering, many uncertain factors in loading or degradation of material properties may vary with time. Stochastic process modeling constitutes a suitable approach for describing these time-dependent uncertainties. By adopting this approach, however, the timedependent reliability calculation is a great challenge owing to the complexity and the huge computational burden. This paper presents a new instantaneous response surface method t-IRS for time-dependent reliability analysis. Different from the adaptive extreme response surface approach, the proposed method does not need to build and update surrogate models separately at each time node. It first uses the expansion optimal linear estimation method to discretize the stochastic processes into a set of independent standard normal variables together with some deterministic functions of time. Time is then treated as an independent one-dimensional variable. Next, initial samples are generated by Latin hypercube sampling, and the corresponding response values are calculated and utilized to construct an instantaneous response surrogate model of the Kriging type. The active learning method is applied to update the Kriging surrogate model until satisfactory accuracy is achieved. Finally, the instantaneous response surrogate model is used to compute the time-dependent reliability via Monte Carlo simulation. Four case studies are utilized to demonstrate the effectiveness of the ^-IRS method for time-dependent reliability analysis.
基金the Beijing Municipal Science&Technology Commission(Z171100001717021)the National Natural Science Foundation of China(81803907).
文摘Objective:To uncover the underlying mechanism of Hewei Jiangni granule(HWJNG)on non-erosive reflux disease(NERD)treatment by examining histological changes,gastrointestinal neurochemicals release and visceral hypersensitivity-related receptor expression in NERD model rats.Methods:A NERD rat model was established via a combination of basal sensitization and acid perfusion.HWJNG treatments at different doses were then administered.Pathological changes to tissues,mast cell(MC)activation,serum levels of esophageal visceral hypersensitivity-related neurochemicals,and transient receptor potential(TRP)receptor mRNA and protein levels were investigated.Results:Compared with the control group,the expression of tryptase in MCs,the changes of intercellular space,and the serum levels of substance P(SP),calcitonin gene-related peptides(CGRP)and proteinaseactivated receptor 2(PAR2)increased in the model group(all P<.05).The expression of TRP vanilloid 1(Trpv1)mRNA decreased in esophagus and dorsal root ganglia(DRG)of the model group(P=.030&P=.013),and the expression of TRP melastatin channel subfamily member 8(Trpm8)mRNA decreased in the esophagus of model group(P<.01).The level of esophageal TRPV1 protein increased in the model group(P<.01)and the level of TRPM8 protein decreased in esophagus and DRG of the model group(both P<.05).Compared with the model group,the serum levels of SP,CGRP,and PAR2 in the mediumdose HWJNG group showed significant decreases(all P<.05).The expression of Trpv1 mRNA in esophagus and DRG of the HWJNG groups and the Omeprazole group remarkably decreased(all P<.05),as was the expression of Trpm8 mRNA in esophagus of the HWJNG groups(all P<.05).Conclusion:HWJNG alleviated visceral hypersensitivity in NERD model rats by regulating TRP-mediated signaling.Our results indicate that HWJNG has potential as a therapeutic agent for NERD.
文摘Over the last decade,the rapid advances of life sciences have significantly increased public awareness and comprehension of dermatological knowledge,resulting in widespread acceptance of scientific skincare in society.The scope of photoprotection has expanded to encompass not only ultraviolet radiation but also visible light(including blue light).Furthermore,photoprotection methods have evolved from light blocking to the repair of cellular damage caused by prolonged light exposure via biological signaling pathways.Blue light(BL)is the portion of sunlight between 400 nm(violet)and 500 nm(cyan),that can penetrate deep into biological tissues,with up to 20%reaching subcutaneous tissues.Similar to UV damage,BL can cause oxidative stress,persistent pigmentation,and extracellular matrix degradation,resulting in skin symptoms such as hyperpigmentation,dullness,lack of radiance,uneven skin tone,and wrinkles.This study investigates the clinical manifestations of BL-induced skin photodamages,as well as the underlying biological mechanisms and proposes rational photoaging prevention strategies.
基金The work is supported by the Sub-Project of“Research on Key Technologies and Equipment of Reservoir Stimulation”of China National Petroleum Corporation Post–14th Five-Year Plan Forward-Looking Major Science and Technology Project“Research on New Technology of Monitoring and Diagnosis of Horizontal Well Hydraulic Fracture Network Distribution Pattern”(2021DJ4502).
文摘Multistage multi-cluster hydraulic fracturing has enabled the economic exploitation of shale reservoirs,but the interpretation of hydraulic fracture parameters is challenging.The pressure signals after pump shutdown are influenced by hydraulic fractures,which can reflect the geometric features of hydraulic fracture.The shutdown pressure can be used to interpret the hydraulic fracture parameters in a real-time and cost-effective manner.In this paper,a mathematical model for shutdown pressure evolution is developed considering the effects of wellbore friction,perforation friction and fluid loss in fractures.An efficient numerical simulation method is established by using the method of characteristics.Based on this method,the impacts of fracture half-length,fracture height,opened cluster and perforation number,and filtration coefficient on the evolution of shutdown pressure are analyzed.The results indicate that a larger fracture half-length may hasten the decay of shutdown pressure,while a larger fracture height can slow down the decay of shutdown pressure.A smaller number of opened clusters and perforations can significantly increase the perforation friction and decrease the overall level of shutdown pressure.A larger filtration coefficient may accelerate the fluid filtration in the fracture and hasten the drop of the shutdown pressure.The simulation method of shutdown pressure,as well as the analysis results,has important implications for the interpretation of hydraulic fracture parameters.
文摘Adult central nervous system （CNS） tissue has a limited capacity to recover after trauma or disease. Recent medical cell therapy using polymeric biomaterial- loaded stem cells with the capability of differentiation to specific neural population has directed focuses toward the recovery of CNS. Fibers that can provide topographical, biochemical and electrical cues would be attractive for directing the differentiation of stem cells into electro-responsive cells such as neuronal cells. Here we report on the fabrication of an electrospun polypyrrole/polylactide composite nanofiber film that direct or determine the fate of mesenchymal stem cells （MSCs）, via combination of aligned surface topography, and electrical stimulation （ES）. The surface morphology, mechanical properties and electric properties of the film were characterized. Comparing with that on random surface film, expression of neurofilament-lowest and nestin of human umbilical cord mesenchymal stem cells （huMSCs） cultured on film with aligned surface topography and ES were obviously enhanced. These results suggest that aligned topography combining with ES facilitates the neurogenic differentiation of huMSCs and the aligned conductive film can act as a potential nerve scaffold.
基金National Natural Science Foundation of China(Nos.82370532,and 82341219)
文摘Background:Histological healing is closely associated with improved long-term clinical outcomes and lowered relapses in patients with ulcerative colitis(UC).Here,we developed a novel diagnostic criterion for assessing histological healing in UC patients.Methods:We conducted a retrospective cohort study in UC patients,whose treatment was iteratively optimized to achieve mucosal healing at Shanghai Tenth People’s Hospital of Tongji University from January 2017 to May 2022.We identified an inflammatory cell enumeration index(ICEI)for assessing histological healing based on the proportions of eosinophils,CD177^(+)neutrophils,and CD40L^(+)T cells in the colonic lamina propria under high power field(HPF),and the outcomes(risks of symptomatic relapses)of achieving histological remission vs.persistent histological inflammation using Kaplan-Meier curves.Intrareader reliability and inter-reader reliability were evaluated by each reader.The relationships to the changes in the Nancy index and the Geboes score were also assessed for responsiveness.The ICEI was further validated in a new cohort of UC patients from other nine university hospitals.Results:We developed an ICEI for clinical diagnosis of histological healing,i.e.,Y=1.701X_(1)+0.758X_(2)+1.347X_(3)-7.745(X_(1),X_(2),and X_(3)represent the proportions of CD177^(+)neutrophils,eosinophils,and CD40L^(+)T cells,respectively,in the colonic lamina propria under HPF).The receiver operating characteristics curve(ROC)analysis revealed that Y<-0.391 was the cutoff value for the diagnosis of histological healing and that an area under the curve(AUC)was 0.942(95%confidence interval[CI]:0.905-0.979)with a sensitivity of 92.5%and a specificity of 83.6%(P<0.001).The intraclass correlation coefficient(ICC)for the intrareader reliability was 0.855(95%CI:0.781-0.909),and ICEI had good inter-reader reliability of 0.832(95%CI:0.748-0.894).During an 18-month follow-up,patients with histological healing had a substantially better outcome compared with those with unachieved histological healing(P<0.001)using ICEI.During a 12-month follow-up from other nine hospitals,patients with histological healing also had a lower risk of relapse than patients with unachieved histological healing.Conclusions:ICEI can be used to predict histological healing and identify patients with a risk of relapse 12 months and 18 months after clinical therapy.Therefore,ICEI provides a promising,simplified approach to monitor histological healing and to predict the prognosis of UC.Registration:Chinese Clinical Trial Registry,No.ChiCTR2300077792.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences (XDA20050102)the National Natural Science Foundation of China (41725003)
文摘The Tibetan Plateau (TP) encompasses Xizang and Qinghai and parts of northern Yunnan and Sichuan provinces, with a total area of circa 2.6 millions km2. The 2013 satellite data showed that grasslands, forests, wetlands, agricultural lands, and deserts account for 60%, 7.7%, 1.4%, 0.3%, and 30%, respectively, of total TP land (1)Due to its existence in dry, high altitude and cold environments, the TP ecosystem is extremely vulnerable to global climate change and studies on the TP ecosystem can be utilized as a pre-warning for other ecosystems.
