Efficiency of calculating a dynamic response is an important point of the compliant mechanism for posture adjustment.Dynamic modeling with low orders of a 2R1T compliant parallel mechanism is studied in the paper.The ...Efficiency of calculating a dynamic response is an important point of the compliant mechanism for posture adjustment.Dynamic modeling with low orders of a 2R1T compliant parallel mechanism is studied in the paper.The mechanism with two out-of-plane rotational and one lifting degrees of freedom(DoFs)plays an important role in posture adjustment.Based on elastic beam theory,the stiffness matrix and mass matrix of the beam element are established where the moment of inertia is considered.To improve solving efficiency,a dynamic model with low orders of the mechanism is established based on a modified modal synthesis method.Firstly,each branch of the RPR type mechanism is divided into a substructure.Subsequently,a set of hypothetical modes of each substructure is obtained based on the C-B method.Finally,dynamic equation of the whole mechanism is established by the substructure assembly.A dynamic experiment is conducted to verify the dynamic characteristics of the compliant mechanism.展开更多
A novel compliant mechanism with RPR degrees of freedom(DOF)is proposed where R and P represent rotation and translation DOFs,respectively.The proposed compliant mechanism is obtained from dimension synthesizing a 2-R...A novel compliant mechanism with RPR degrees of freedom(DOF)is proposed where R and P represent rotation and translation DOFs,respectively.The proposed compliant mechanism is obtained from dimension synthesizing a 2-RPU-UPR rigid parallel mechanism with the method of optimization of motion/force transfer characteristic.R,P and U represent rotation,translation and universal pairs,respectively.Firstly,inverse kinematics and Jacobian matrix are analyzed for the dimensional synthesis.Then,output transmission indexes of branches in the parallel mechanism are given.Dimensional synthesis is completed based on the normalized design parameter.And optimization of flexure joints based on constrained energy is carried out.Afterwards,the novel compliant mechanism is obtained by direct replacing method.Mechanical model of the compliant mechanism including static stiffness and input stiffness is built based on the pseudo-rigid body modeling method and virtual work principle.Finally,FEA simulation by Ansys Workbench is carried out to verify DOF,effectiveness of the dimension synthesis,and compliant model.Optimization of motion/force transfer characteristic is first applied for the design of compliant mechanisms to suppress drift of rotation axis in the paper.展开更多
The stationary phase of microbial growth is a very complex state regulated by various environmental and physiological factors. An intensive study of stationary phase could promote a comprehensive understanding of the ...The stationary phase of microbial growth is a very complex state regulated by various environmental and physiological factors. An intensive study of stationary phase could promote a comprehensive understanding of the complete life cycle of microorganisms, and may provide important insights into their adaptation to harsh and nutrient-depleted conditions. Although the underlying mechanisms have been weU-studied in bacteria and yeasts （Herman, 2002; Navarro Llorens et al., 2010）, less is known about this growth phase in archaea yet. The haloarchaeon Haloferax mediterranei has served as a good model for studying haloarchaeal physiology and metabolism for several decades because of its accelerated growth, remarkable metabolic ability and genomic stability （Han et al., 2012）. During stationary phase, H. mediterranei can produce halocin H4 （Cheung et al.,展开更多
Background and Objectives:To investigate the correlation between weight-adjusted-waist index(WWI),a novel obesity index,and serum ferritin(SF)level in patients with type 2 diabetes mellitus(T2DM),and the association b...Background and Objectives:To investigate the correlation between weight-adjusted-waist index(WWI),a novel obesity index,and serum ferritin(SF)level in patients with type 2 diabetes mellitus(T2DM),and the association between WWI and the prevalence of hyperferritinemia.Methods and Study Design:A total of 943 patients with T2DM were divided into three groups based on WWI tertile levels.Disparities in SF levels and the prevalence of hyperferritinemia were compared among these groups.The correlations among WWI,SF levels,and hyperferritinemia were analyzed in patients with T2DM.Results:As WWI tertile levels increased,SF levels tended to increase(p for trend<0.01).A statistically significant positive correlation was observed between the WWI and SF levels(R=0.263,p<0.001).After adjusting for confounders by multiple linear regression,a significant positive correlation was maintained between the WWI and SF levels[β=0.194,95%CI(49.914,112.120),p<0.01].Binary logistic regression analysis revealed a positive association between the WWI and the likelihood of hyperferritinemia,with a notably stronger correlation observed in females compared to males[OR=3.248,95%CI(2.027,5.204),p<0.01 vs.OR=2.091,95%CI(1.432,3.054),p<0.01].Conclusions:Along with increasing WWI,SF levels gradually increased in patients with T2DM.The WWI exhibited a positive correlation with SF levels and hyperferritinemia,more significantly in female patients.展开更多
Background and Objectives:To investigate the relationship between geriatric nutritional risk index(GNRI)and osteoporosis(OP)in postmenopausal elderly women with type 2 diabetes mellitus(T2DM).Methods and Study Design:...Background and Objectives:To investigate the relationship between geriatric nutritional risk index(GNRI)and osteoporosis(OP)in postmenopausal elderly women with type 2 diabetes mellitus(T2DM).Methods and Study Design:A total of 141 postmenopausal elderly women with T2DM was divided into OP and normal bone mineral density(BMD)groups,the differences in GRNI levels between the two groups were compared.According to the tertile levels of GRNI,T2DM were divided into three groups(T1,T2,T3 groups),and the differences in OP prevalence and levels of BMD among the three groups were compared.Results:Among postmenopausal elderly women with T2DM,GNRI levels were lower in the OP group compared to the normal BMD group[(103±5.46)vs.(105±5.46),p<0.05)].With elevated GNRI levels,the BMD levels of femoral,total hip,total body,and lumbar vertebrae(L)were gradually increased,which were higher in the T3 group than in the T1 group(all p<0.05).GNRI levels were positively correlated with the BMD levels of femoral,spine,total hip,total body,L1,L2,L3,L4,and L1-L4.GNRI was an independent influencing factor for the occurrence of OP(OR=0.887,95%CI[0.795,0.988]).The ROC curve showed that the GNRI combined with serum ALP and P levels had a high predictive value for OP,with an area under the curve of 0.725(p<0.01).Conclusions:In postmenopausal elderly women with T2DM,GNRI was independently and positively correlated with BMD levels.GNRI may be a predictor development of OP.展开更多
Soil interparticle forces can pose important effects on soil aggregate stability and rainfall splash erosion.Meanwhile,these interparticle forces are strongly influenced by specific ion effects.In this study,we applie...Soil interparticle forces can pose important effects on soil aggregate stability and rainfall splash erosion.Meanwhile,these interparticle forces are strongly influenced by specific ion effects.In this study,we applied three monovalent cations(Li^(+),Na^(+),and K^(+))with various concentrations to investigate the influence of specific ion effects on aggregate stability and splash erosion via pipette and rainfall simulation methods.The specific ion effects on soil interparticle forces were quantitatively evaluated by introducing cationic non-classical polarization.The results showed that aggregate stability and splash erosion had strong ion specificity.Aggregate breaking strength and splash erosion rate at the same salt concentration followed the sequence as Li^(+)>Na^(+)>K^(+).With decreasing salt concentration,the difference in aggregate breaking strength or splash erosion rate between different cation systems increased initially(1–10^(-2)mol L^(–1))and later was nearly invariable(10^(–2)–10^(–4)mol L^(–1)).The experimental results were well quantitatively explained by soil interparticle forces considering cationic non-classical polarization.Furthermore,both aggregate breaking strength and splash erosion rate of three cations revealed a strong positive linear relation with net force subjected to cationic non-classical polarization(R^(2)=0.81,R^(2)=0.81).These results demonstrated that different non-classical polarization of cations resulted in different soil interparticle forces,and thus led to differences in aggregate stability and splash erosion.Our study provides valuable information to deeply understand the mechanisms of rainfall splash erosion.展开更多
The“gut-liver”axis plays an important role in the mechanism of alcoholic liver disease(ALD).Sporidiobolus pararoseus polysaccharides(SPP)have been shown to improve the gut barrier and liver damage in mice with ALD.H...The“gut-liver”axis plays an important role in the mechanism of alcoholic liver disease(ALD).Sporidiobolus pararoseus polysaccharides(SPP)have been shown to improve the gut barrier and liver damage in mice with ALD.However,the process is modulated via the gut microbiome and amino acids in the gut-liver axis has not been elucidated.In this study,the gut microbiome and metabolic function were explored for the mechanism by which SPP improve ALD.The results showed that after the SPP were metabolized by ALD mice,microbial diversity was altered,and the relative abundances of Lachnospiraceae,Alistipes,Eubacterium siraeum,and Bacteroides increased.The predicted results of microbiome functions promoted the biosynthesis of amino acids,tyrosine,tryptophan,valine,leucine,and isoleucine were enhanced.Metabolomics results also confirmed that butanoate metabolism and biosynthesis of phenylalanine,tyrosine,and tryptophan are the main regulatory pathways of SPP.The gut microbiome metabolizes the hallmark metabolites of SPP were L-tyrosine,L-histidine,and L-serine.Correlation analysis and interaction network deeply mine gut microbiome(Lachnospiraceae,Eubacterium siraeum,Erysipelotrichaceae),metabolites(Lserine,Ltyrosine),and metabolism(biosynthesis of amino acids,valine,leucine,and isoleucine biosynthesis)may be key factors in the SPP-gut microbiome-metabolites-metabolism in ALD mice.Therefore,SPP have the effect of proliferating beneficial gut microbiome that metabolize polysaccharides,promoting the production of amino acids,and regulating liver metabolic disorders.展开更多
Summary What is already known about this topic?The coronavirus disease 2019(COVID-19)pandemic poses a significant threat to mental health globally and may change the proportion of hospitalized patients.What is added b...Summary What is already known about this topic?The coronavirus disease 2019(COVID-19)pandemic poses a significant threat to mental health globally and may change the proportion of hospitalized patients.What is added by this report?This report analyzed and compared the disease characteristics of psychiatric inpatients one year before and after Wuhan lifted lockdown during COVID-19.About 50%of the inpatients were diagnosed with bipolar disorder;females and adolescents had a higher prevalence of mental disorders.What are the implications for public health practice?More attention should be paid to the mental health of children,adolescents,and females.展开更多
基金Supported by National Natural Science Foundation of China (Grant No.51975007)。
文摘Efficiency of calculating a dynamic response is an important point of the compliant mechanism for posture adjustment.Dynamic modeling with low orders of a 2R1T compliant parallel mechanism is studied in the paper.The mechanism with two out-of-plane rotational and one lifting degrees of freedom(DoFs)plays an important role in posture adjustment.Based on elastic beam theory,the stiffness matrix and mass matrix of the beam element are established where the moment of inertia is considered.To improve solving efficiency,a dynamic model with low orders of the mechanism is established based on a modified modal synthesis method.Firstly,each branch of the RPR type mechanism is divided into a substructure.Subsequently,a set of hypothetical modes of each substructure is obtained based on the C-B method.Finally,dynamic equation of the whole mechanism is established by the substructure assembly.A dynamic experiment is conducted to verify the dynamic characteristics of the compliant mechanism.
基金National Natural Science Foundation of China(Grant No.51975007).
文摘A novel compliant mechanism with RPR degrees of freedom(DOF)is proposed where R and P represent rotation and translation DOFs,respectively.The proposed compliant mechanism is obtained from dimension synthesizing a 2-RPU-UPR rigid parallel mechanism with the method of optimization of motion/force transfer characteristic.R,P and U represent rotation,translation and universal pairs,respectively.Firstly,inverse kinematics and Jacobian matrix are analyzed for the dimensional synthesis.Then,output transmission indexes of branches in the parallel mechanism are given.Dimensional synthesis is completed based on the normalized design parameter.And optimization of flexure joints based on constrained energy is carried out.Afterwards,the novel compliant mechanism is obtained by direct replacing method.Mechanical model of the compliant mechanism including static stiffness and input stiffness is built based on the pseudo-rigid body modeling method and virtual work principle.Finally,FEA simulation by Ansys Workbench is carried out to verify DOF,effectiveness of the dimension synthesis,and compliant model.Optimization of motion/force transfer characteristic is first applied for the design of compliant mechanisms to suppress drift of rotation axis in the paper.
基金supported by the grants from the National Natural Science Foundation of China(Nos.30925001 and 31271334)the Chinese Academy of Sciences(No. KSCX2-EW-G-2-4)
文摘The stationary phase of microbial growth is a very complex state regulated by various environmental and physiological factors. An intensive study of stationary phase could promote a comprehensive understanding of the complete life cycle of microorganisms, and may provide important insights into their adaptation to harsh and nutrient-depleted conditions. Although the underlying mechanisms have been weU-studied in bacteria and yeasts （Herman, 2002; Navarro Llorens et al., 2010）, less is known about this growth phase in archaea yet. The haloarchaeon Haloferax mediterranei has served as a good model for studying haloarchaeal physiology and metabolism for several decades because of its accelerated growth, remarkable metabolic ability and genomic stability （Han et al., 2012）. During stationary phase, H. mediterranei can produce halocin H4 （Cheung et al.,
基金funded by the National Natural Science Foundation of China(No.81960155 and No.82360161)the Science Foundation of Gansu Provincial Maternity and Child-care Hospital(GMCCH2024-3-2)the Lanzhou Science and Technology Bureau(2022-3-46).
文摘Background and Objectives:To investigate the correlation between weight-adjusted-waist index(WWI),a novel obesity index,and serum ferritin(SF)level in patients with type 2 diabetes mellitus(T2DM),and the association between WWI and the prevalence of hyperferritinemia.Methods and Study Design:A total of 943 patients with T2DM were divided into three groups based on WWI tertile levels.Disparities in SF levels and the prevalence of hyperferritinemia were compared among these groups.The correlations among WWI,SF levels,and hyperferritinemia were analyzed in patients with T2DM.Results:As WWI tertile levels increased,SF levels tended to increase(p for trend<0.01).A statistically significant positive correlation was observed between the WWI and SF levels(R=0.263,p<0.001).After adjusting for confounders by multiple linear regression,a significant positive correlation was maintained between the WWI and SF levels[β=0.194,95%CI(49.914,112.120),p<0.01].Binary logistic regression analysis revealed a positive association between the WWI and the likelihood of hyperferritinemia,with a notably stronger correlation observed in females compared to males[OR=3.248,95%CI(2.027,5.204),p<0.01 vs.OR=2.091,95%CI(1.432,3.054),p<0.01].Conclusions:Along with increasing WWI,SF levels gradually increased in patients with T2DM.The WWI exhibited a positive correlation with SF levels and hyperferritinemia,more significantly in female patients.
基金funded by National Natural Science Foundation of China(No.81960155No.82360161)+1 种基金Science and Technology Department of Lanzhou City(No.2022-3-46)Lanzhou University First Hospital Intra-Hospital Fund(No.ldyyyn2020-01).
文摘Background and Objectives:To investigate the relationship between geriatric nutritional risk index(GNRI)and osteoporosis(OP)in postmenopausal elderly women with type 2 diabetes mellitus(T2DM).Methods and Study Design:A total of 141 postmenopausal elderly women with T2DM was divided into OP and normal bone mineral density(BMD)groups,the differences in GRNI levels between the two groups were compared.According to the tertile levels of GRNI,T2DM were divided into three groups(T1,T2,T3 groups),and the differences in OP prevalence and levels of BMD among the three groups were compared.Results:Among postmenopausal elderly women with T2DM,GNRI levels were lower in the OP group compared to the normal BMD group[(103±5.46)vs.(105±5.46),p<0.05)].With elevated GNRI levels,the BMD levels of femoral,total hip,total body,and lumbar vertebrae(L)were gradually increased,which were higher in the T3 group than in the T1 group(all p<0.05).GNRI levels were positively correlated with the BMD levels of femoral,spine,total hip,total body,L1,L2,L3,L4,and L1-L4.GNRI was an independent influencing factor for the occurrence of OP(OR=0.887,95%CI[0.795,0.988]).The ROC curve showed that the GNRI combined with serum ALP and P levels had a high predictive value for OP,with an area under the curve of 0.725(p<0.01).Conclusions:In postmenopausal elderly women with T2DM,GNRI was independently and positively correlated with BMD levels.GNRI may be a predictor development of OP.
基金supported by the National Natural Science Foundation of China(41977024,41601236)the Fundamental Research Funds for the Central Universities(2452019078).
文摘Soil interparticle forces can pose important effects on soil aggregate stability and rainfall splash erosion.Meanwhile,these interparticle forces are strongly influenced by specific ion effects.In this study,we applied three monovalent cations(Li^(+),Na^(+),and K^(+))with various concentrations to investigate the influence of specific ion effects on aggregate stability and splash erosion via pipette and rainfall simulation methods.The specific ion effects on soil interparticle forces were quantitatively evaluated by introducing cationic non-classical polarization.The results showed that aggregate stability and splash erosion had strong ion specificity.Aggregate breaking strength and splash erosion rate at the same salt concentration followed the sequence as Li^(+)>Na^(+)>K^(+).With decreasing salt concentration,the difference in aggregate breaking strength or splash erosion rate between different cation systems increased initially(1–10^(-2)mol L^(–1))and later was nearly invariable(10^(–2)–10^(–4)mol L^(–1)).The experimental results were well quantitatively explained by soil interparticle forces considering cationic non-classical polarization.Furthermore,both aggregate breaking strength and splash erosion rate of three cations revealed a strong positive linear relation with net force subjected to cationic non-classical polarization(R^(2)=0.81,R^(2)=0.81).These results demonstrated that different non-classical polarization of cations resulted in different soil interparticle forces,and thus led to differences in aggregate stability and splash erosion.Our study provides valuable information to deeply understand the mechanisms of rainfall splash erosion.
基金supported by the National Key Research and Development Program of China(Nos.2020YFC1606800).
文摘The“gut-liver”axis plays an important role in the mechanism of alcoholic liver disease(ALD).Sporidiobolus pararoseus polysaccharides(SPP)have been shown to improve the gut barrier and liver damage in mice with ALD.However,the process is modulated via the gut microbiome and amino acids in the gut-liver axis has not been elucidated.In this study,the gut microbiome and metabolic function were explored for the mechanism by which SPP improve ALD.The results showed that after the SPP were metabolized by ALD mice,microbial diversity was altered,and the relative abundances of Lachnospiraceae,Alistipes,Eubacterium siraeum,and Bacteroides increased.The predicted results of microbiome functions promoted the biosynthesis of amino acids,tyrosine,tryptophan,valine,leucine,and isoleucine were enhanced.Metabolomics results also confirmed that butanoate metabolism and biosynthesis of phenylalanine,tyrosine,and tryptophan are the main regulatory pathways of SPP.The gut microbiome metabolizes the hallmark metabolites of SPP were L-tyrosine,L-histidine,and L-serine.Correlation analysis and interaction network deeply mine gut microbiome(Lachnospiraceae,Eubacterium siraeum,Erysipelotrichaceae),metabolites(Lserine,Ltyrosine),and metabolism(biosynthesis of amino acids,valine,leucine,and isoleucine biosynthesis)may be key factors in the SPP-gut microbiome-metabolites-metabolism in ALD mice.Therefore,SPP have the effect of proliferating beneficial gut microbiome that metabolize polysaccharides,promoting the production of amino acids,and regulating liver metabolic disorders.
文摘Summary What is already known about this topic?The coronavirus disease 2019(COVID-19)pandemic poses a significant threat to mental health globally and may change the proportion of hospitalized patients.What is added by this report?This report analyzed and compared the disease characteristics of psychiatric inpatients one year before and after Wuhan lifted lockdown during COVID-19.About 50%of the inpatients were diagnosed with bipolar disorder;females and adolescents had a higher prevalence of mental disorders.What are the implications for public health practice?More attention should be paid to the mental health of children,adolescents,and females.
