针对锚固节理岩体在恒定法向刚度(constant normal stiffness,CNS)条件下剪切特性与破坏机制研究不足的问题,基于离散元模拟构建了锚固节理岩体数值模型,开展了系统的数值剪切实验。通过改变法向刚度、结构面粗糙度系数(joint surface r...针对锚固节理岩体在恒定法向刚度(constant normal stiffness,CNS)条件下剪切特性与破坏机制研究不足的问题,基于离散元模拟构建了锚固节理岩体数值模型,开展了系统的数值剪切实验。通过改变法向刚度、结构面粗糙度系数(joint surface roughness coefficient,JRC)、初始法向应力和锚杆弹性模量4个关键参数,探讨其对岩体剪切应力应变特征、法向应力演化、法向位移行为及内力响应的影响。结果表明:法向刚度对剪切应力应变曲线具有多阶段调控作用;JRC与峰值剪切应力呈近似指数关系,并显著影响法向应力的双阶段演化过程及法向位移曲线特征;初始法向应力调控剪切过程中的多阶段强度表现及法向位移的发展时序;锚杆弹性模量对峰值剪切应力具有非线性调控效应,低弹性模量强化效应平缓,高弹性模量则显著提升剪切应力,且其内力响应规律符合Boltzmann模型描述。研究揭示了CNS条件下多因素协同作用对锚固岩体剪切行为的影响机制,为岩土工程中锚固参数的合理选取与稳定性控制提供了理论支撑。展开更多
In the mammalian central nervous system(CNS),astrocytes are the ubiquitous glial cells that have complex morphological and molecular characteristics.These fascinating cells play essential neurosupportive and homeostat...In the mammalian central nervous system(CNS),astrocytes are the ubiquitous glial cells that have complex morphological and molecular characteristics.These fascinating cells play essential neurosupportive and homeostatic roles in the healthy CNS and undergo morphological,molecular,and functional changes to adopt so-called‘reactive’states in response to CNS injury or disease.In recent years,interest in astrocyte research has increased dramatically and some new biological features and roles of astrocytes in physiological and pathological conditions have been discovered thanks to technological advances.Here,we will review and discuss the wellestablished and emerging astroglial biology and functions,with emphasis on their potential as therapeutic targets for CNS injury,including traumatic and ischemic injury.This review article will highlight the importance of astrocytes in the neuropathological process and repair of CNS injury.展开更多
Although high-dose methotrexate(HD-MTX)is the most effective drug against primary CNS lymphomas(PCNSL),outcome-de-termining variables related to its administration schedule have not been defined.The impact on toxicity...Although high-dose methotrexate(HD-MTX)is the most effective drug against primary CNS lymphomas(PCNSL),outcome-de-termining variables related to its administration schedule have not been defined.The impact on toxicity and outcome of the area under thecurve(AUC(MTX)),dose intensity(DI(MTX))and infusion rate(IR(MTX))of MTX and plsamatic creatinine clearance(CL(crea))was investigated in a retrospective series of 45 PCNSL patients treated with three different HD-MTX-basedcombinations.Anticon-vulsants were administered in 31 pts(69%).Age>60 years,anticonvulsant therapy,slow IR(MTX)(</=800 mgm(-2)h(-1)),and reduced DI(MTX)(</=1000 mgm(-2)wk(-1))were significantly correlated with low AUC(MTX)values.Seven pa-展开更多
为了研究通信导航监视(communicatio,navigation and surveillance,CNS)下的定位误差和纵向碰撞风险及其影响因素,在Reich模型的基础上,分析通信、导航和监视误差,推导出平行航路纵向重叠概率的计算公式.据此建立了基于CNS性能的平行航...为了研究通信导航监视(communicatio,navigation and surveillance,CNS)下的定位误差和纵向碰撞风险及其影响因素,在Reich模型的基础上,分析通信、导航和监视误差,推导出平行航路纵向重叠概率的计算公式.据此建立了基于CNS性能的平行航路纵向碰撞风险评估模型.算例表明,所给定的平行航路在RCP400、RNP10和RSP20条件下,碰撞风险为3.0×10-10,达到国际民航组织安全目标水平的要求.评估模型是可行的.展开更多
基金supported by the National Natural Science Foundation of China(82171386,81971161,and 82201536)the Shanghai Science and Technology Development Foundation(22YF1458600)+1 种基金the Scientifc Foundation from Naval Medical University(2021QN08)the STI2030-Major Projects from Ministry of Science and Technology of China(2022ZD0204700).
文摘In the mammalian central nervous system(CNS),astrocytes are the ubiquitous glial cells that have complex morphological and molecular characteristics.These fascinating cells play essential neurosupportive and homeostatic roles in the healthy CNS and undergo morphological,molecular,and functional changes to adopt so-called‘reactive’states in response to CNS injury or disease.In recent years,interest in astrocyte research has increased dramatically and some new biological features and roles of astrocytes in physiological and pathological conditions have been discovered thanks to technological advances.Here,we will review and discuss the wellestablished and emerging astroglial biology and functions,with emphasis on their potential as therapeutic targets for CNS injury,including traumatic and ischemic injury.This review article will highlight the importance of astrocytes in the neuropathological process and repair of CNS injury.
文摘Although high-dose methotrexate(HD-MTX)is the most effective drug against primary CNS lymphomas(PCNSL),outcome-de-termining variables related to its administration schedule have not been defined.The impact on toxicity and outcome of the area under thecurve(AUC(MTX)),dose intensity(DI(MTX))and infusion rate(IR(MTX))of MTX and plsamatic creatinine clearance(CL(crea))was investigated in a retrospective series of 45 PCNSL patients treated with three different HD-MTX-basedcombinations.Anticon-vulsants were administered in 31 pts(69%).Age>60 years,anticonvulsant therapy,slow IR(MTX)(</=800 mgm(-2)h(-1)),and reduced DI(MTX)(</=1000 mgm(-2)wk(-1))were significantly correlated with low AUC(MTX)values.Seven pa-
文摘为了研究通信导航监视(communicatio,navigation and surveillance,CNS)下的定位误差和纵向碰撞风险及其影响因素,在Reich模型的基础上,分析通信、导航和监视误差,推导出平行航路纵向重叠概率的计算公式.据此建立了基于CNS性能的平行航路纵向碰撞风险评估模型.算例表明,所给定的平行航路在RCP400、RNP10和RSP20条件下,碰撞风险为3.0×10-10,达到国际民航组织安全目标水平的要求.评估模型是可行的.
