A caisson breakwater is built on soft foundations after replacing the upper soft layer with sand. This paper presents a dynamic finite element method to investigate the strength degradation and associated pore pressur...A caisson breakwater is built on soft foundations after replacing the upper soft layer with sand. This paper presents a dynamic finite element method to investigate the strength degradation and associated pore pressure development of the intercalated soft layer under wave cyclic loading. By combining the undrained shear strength with the empirical formula of overconsolidation clay produced by unloading and the development model of pore pressure, the dynamic degradation law that describes the undrained shear strength as a function of cycle number and stress level is derived. Based on the proposed dynamic degradation law and M-C yield criterion, a dynamic finite element method is numerically implemented to predict changes in undrained shear strength of the intercalated soft layer by using the general-purpose FEM software ABAQUS, and the accuracy of the method is verified. The effects of cycle number and amplitude of the wave force on the degradation of the undrained shear strength of the intercalated soft layer and the associated excess pore pressure response are investigated by analyzing an overall distribution and three typical sections underneath the breakwater. By comparing the undrained shear strength distributions obtained by the static method and the quasi-static method with the undrained shear strength distributions obtained by the dynamic finite element method in the three typical sections, the superiority of the dynamic finite element method in predicting changes in undrained shear strength is demonstrated.展开更多
The striatum, as the primary input nucleus in the basal ganglion,plays an important role in neural circuits crucial for the control of critical motivation, motor planning and procedural learning(Kreitzer and Malenka, ...The striatum, as the primary input nucleus in the basal ganglion,plays an important role in neural circuits crucial for the control of critical motivation, motor planning and procedural learning(Kreitzer and Malenka, 2008). Most cells in the striatum are GABAergic, including a large population (90%-95%) of medium spiny neurons (MSNs) and a small population of interneurons.展开更多
Introduction-The cervical spine is subjected to injury frequently,especially among pilots who are usually on the condition of high acceleration.Injuries of the cervical spine will be potential risk of damage to the sp...Introduction-The cervical spine is subjected to injury frequently,especially among pilots who are usually on the condition of high acceleration.Injuries of the cervical spine will be potential risk of damage to the spinal cord,which could be result in life threatening展开更多
September 2017 Contents Preface Ensuring People’s Right to Health Based on China’s Conditions Continuous Improvement of Health Environment and Conditions Public Health Service Capability Improving Steadily Great Imp...September 2017 Contents Preface Ensuring People’s Right to Health Based on China’s Conditions Continuous Improvement of Health Environment and Conditions Public Health Service Capability Improving Steadily Great Improvement in the Quality of Medical and Health Services Improvement of the National Medical Security System展开更多
Objective To search for the potential medicinal plant part of Gentiana macrophyllabased on changes of secondary metabolites and trace elements in the flowers of G.macrophylla.Methods HPLC was used to detect the change...Objective To search for the potential medicinal plant part of Gentiana macrophyllabased on changes of secondary metabolites and trace elements in the flowers of G.macrophylla.Methods HPLC was used to detect the changes of the active constituents(longanic acid,sweroside,gentiopicroside,and swertiamarin)and ICP-AES was used for mineral nutrients in G.macrophylla during flower development.And soluble sugar,starch,crude protein,hemicelluloses,cellulose,and lignin were determined.Results Biomass of flower in full bloom(D2)phase was considerable during flower development,in which the contents of longanic acid and gentiopicroside were at the highest levels with 2.65 and 2.88 times higher than those recorded in Chinese Pharmacopoeia 2010,sweroside and swertiamarin in the flowers were reaching 6.06 and 1.25 times higher than those in roots.Florescence is the most valuable stage during flower development.The concentration of Fe,Mg,K,P,and B was higher in the flowers than that in roots.The accumulation of active constituents in the plant was influenced by the contents of metabolically linked carbon and nitrogen compounds.Conclusion The secondary metabolites,mineral nutrients,and physicochemical indicators are tightly regulated by flower organ development,D2 is an important stage for both biomass and extraction of active constituents such as longanic acid.The flowers of G.macrophylla could be used as a potential medicinal plant part for longanic acid at a high level.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant No.51279128)the National Natural Science Fund for Innovative Research Groups Science Foundation(Grant No.51321065)the Construction Science and Technology Project of Ministry of Transport of the People’s Republic of China(Grant No.2013328224070)
文摘A caisson breakwater is built on soft foundations after replacing the upper soft layer with sand. This paper presents a dynamic finite element method to investigate the strength degradation and associated pore pressure development of the intercalated soft layer under wave cyclic loading. By combining the undrained shear strength with the empirical formula of overconsolidation clay produced by unloading and the development model of pore pressure, the dynamic degradation law that describes the undrained shear strength as a function of cycle number and stress level is derived. Based on the proposed dynamic degradation law and M-C yield criterion, a dynamic finite element method is numerically implemented to predict changes in undrained shear strength of the intercalated soft layer by using the general-purpose FEM software ABAQUS, and the accuracy of the method is verified. The effects of cycle number and amplitude of the wave force on the degradation of the undrained shear strength of the intercalated soft layer and the associated excess pore pressure response are investigated by analyzing an overall distribution and three typical sections underneath the breakwater. By comparing the undrained shear strength distributions obtained by the static method and the quasi-static method with the undrained shear strength distributions obtained by the dynamic finite element method in the three typical sections, the superiority of the dynamic finite element method in predicting changes in undrained shear strength is demonstrated.
基金supported by grants from the National Key Research and Development Program of China (2016YFA0100702 and 2016YFC0902502)the National Natural Science Foundation of China (31670789 and 31671316)the CAMS Innovation Fund for Medical Sciences (CIFMS, 2016I2M-2-001, 2016-I2M-1-001, 2016-I2M-1-004 and 2017-I2M-1004)
文摘The striatum, as the primary input nucleus in the basal ganglion,plays an important role in neural circuits crucial for the control of critical motivation, motor planning and procedural learning(Kreitzer and Malenka, 2008). Most cells in the striatum are GABAergic, including a large population (90%-95%) of medium spiny neurons (MSNs) and a small population of interneurons.
文摘Introduction-The cervical spine is subjected to injury frequently,especially among pilots who are usually on the condition of high acceleration.Injuries of the cervical spine will be potential risk of damage to the spinal cord,which could be result in life threatening
文摘September 2017 Contents Preface Ensuring People’s Right to Health Based on China’s Conditions Continuous Improvement of Health Environment and Conditions Public Health Service Capability Improving Steadily Great Improvement in the Quality of Medical and Health Services Improvement of the National Medical Security System
基金Major National Science and Technology Program(2009ZX09308)
文摘Objective To search for the potential medicinal plant part of Gentiana macrophyllabased on changes of secondary metabolites and trace elements in the flowers of G.macrophylla.Methods HPLC was used to detect the changes of the active constituents(longanic acid,sweroside,gentiopicroside,and swertiamarin)and ICP-AES was used for mineral nutrients in G.macrophylla during flower development.And soluble sugar,starch,crude protein,hemicelluloses,cellulose,and lignin were determined.Results Biomass of flower in full bloom(D2)phase was considerable during flower development,in which the contents of longanic acid and gentiopicroside were at the highest levels with 2.65 and 2.88 times higher than those recorded in Chinese Pharmacopoeia 2010,sweroside and swertiamarin in the flowers were reaching 6.06 and 1.25 times higher than those in roots.Florescence is the most valuable stage during flower development.The concentration of Fe,Mg,K,P,and B was higher in the flowers than that in roots.The accumulation of active constituents in the plant was influenced by the contents of metabolically linked carbon and nitrogen compounds.Conclusion The secondary metabolites,mineral nutrients,and physicochemical indicators are tightly regulated by flower organ development,D2 is an important stage for both biomass and extraction of active constituents such as longanic acid.The flowers of G.macrophylla could be used as a potential medicinal plant part for longanic acid at a high level.