用0、50、100、150和200 m M Na Cl溶液处理不同秋眠等级紫花苜蓿标准品种Maverick、Archer和CUF101,观察形态特征和盐害级别,测定叶片净光合速率(Pn)、细胞间隙CO2浓度(Ci)和气孔导度(Gs),分析盐胁迫对不同秋眠等级紫花苜蓿光合特性的...用0、50、100、150和200 m M Na Cl溶液处理不同秋眠等级紫花苜蓿标准品种Maverick、Archer和CUF101,观察形态特征和盐害级别,测定叶片净光合速率(Pn)、细胞间隙CO2浓度(Ci)和气孔导度(Gs),分析盐胁迫对不同秋眠等级紫花苜蓿光合特性的影响.不同秋眠等级紫花苜蓿植株叶片盐害级别随品种和处理浓度不同而不同,但均随Na Cl浓度的增加和胁迫时间的延长而加大.在较低Na Cl浓度下Maverick、Archer和CUF101光合响应存在着预警阶段-恢复阶段-耗尽阶段,在高Na Cl浓度下,所有的供试品种光合响应直接进入耗尽阶段.展开更多
The number of patients with chronic kidney disease re-quiring renal replacement therapy has increased world-wide. The most common replacement therapy is hemo-dialysis （HD）. Vascular access （VA） has a key role for ...The number of patients with chronic kidney disease re-quiring renal replacement therapy has increased world-wide. The most common replacement therapy is hemo-dialysis （HD）. Vascular access （VA） has a key role for successful treatment. Despite the advances that have taken place in the feld of the HD procedure, few things have changed with regards to VA in recent years. Ar-teriovenous fstula （AVF）, polytetrafuoroethylene graft and the cuffed double lumen silicone catheter are the most common used for VA. In the long term, a number of complications may present and more than one VA is needed during the HD life. The most common com-plications for all of VA types are thrombosis, bleeding and infection, the most common cause of morbidity in these patients. It has been estimated that VA dysfunc-tion is responsible for 20% of all hospitalizations. The annual cost of placing and looking after dialysis VA in the United States exceeds 1 billion dollars per year. A good functional access is also vital in order to deliver adequate HD therapy. It seems that the native AVF that Brescia and Cimino described in 1966 still remains the frst choice for VA. The native forearm AVFs have the longest survival and require the fewest interventions. For this reason, the forearm AVF is the frst choice, fol-lowed by the upper-arm AVF, the arteriovenous graft and the cuffed central venous catheter is the final choice. In conclusion, VA remains the most importantissue for patients on HD and despite the technical im-provements, a number of problems and complications have to be resolved.展开更多
The mechanical behavior of advanced composites can be modeled mathematically through unknown variables and Shear Strain Thickness Functions(SSTFs). Such SSTFs can be of polynomial or non-polynomial nature and some par...The mechanical behavior of advanced composites can be modeled mathematically through unknown variables and Shear Strain Thickness Functions(SSTFs). Such SSTFs can be of polynomial or non-polynomial nature and some parameters of non-polynomial SSTFs can be optimized to get optimal results. In this paper, these parameters are called ‘‘r" and ‘‘s" and they are the argument of the trigonometric SSTFs introduced within the Carrera Unified Formulation(CUF). The Equivalent Single Layer(ESL) governing equations are obtained by employing the Principle of Virtual Displacement(PVD) and are solved using Navier method solution. Furthermore, trigonometric expansion with Murakami theory was implemented in order to reproduce the Zig-Zag effects which are important for multilayer structures. Several combinations of optimization parameters are evaluated and selected by different criteria of average error. Results of the present unified trigonometrical theory with CUF bases confirm that it is possible to improve the stress and displacement results through the thickness distribution of models with reduced unknown variables. Since the idea is to find a theory with reduced numbers of unknowns, the present method appears to be an appropriate technique to select a simple model. However these optimization parameters depend on the plate geometry and the order of expansion or unknown variables. So, the topic deserves further research.展开更多
Panel flutter phenomena can be strongly affected by thermal loads,and so a refined aeroelastic model is presented.Higher-order shell theories are used as structural models.The aerodynamic forces are described using th...Panel flutter phenomena can be strongly affected by thermal loads,and so a refined aeroelastic model is presented.Higher-order shell theories are used as structural models.The aerodynamic forces are described using the Piston theory.The temperature is considered uniform over the thickness of the panel.The aero-thermo-elastic model is derived in the framework of the Carrera unified formulation(CUF),therefore the matrices are expressed in a compact form using the″fundamental nuclei″.Composite and sandwich structures are considered and different boundary conditions are taken into account.The effects of the thermal load on the aeroelastic behavior are investigated.展开更多
The buckling of thin-walled structures is presented using the 1D finite element based refined beam theory formulation that permits us to obtain N-order expansions for the three displacement fields over the section dom...The buckling of thin-walled structures is presented using the 1D finite element based refined beam theory formulation that permits us to obtain N-order expansions for the three displacement fields over the section domain.These higher-order models are obtained in the framework of the Carrera unified formulation(CUF).CUF is a hierarchical formulation in which the refined models are obtained with no need for ad hoc formulations.Beam theories are obtained on the basis of Taylor-type and Lagrange polynomial expansions.Assessments of these theories have been carried out by their applications to studies related to the buckling of various beam structures,like the beams with square cross section,I-section,thin rectangular cross section,and annular beams.The results obtained match very well with those from commercial finite element softwares with a significantly less computational cost.Further,various types of modes like the bending modes,axial modes,torsional modes,and circumferential shell-type modes are observed.展开更多
Immune cell accumulation and white matter anomaly are common features of HIV(human immunodeficiency virus)-infected patients in combination antiretroviral therapy(cART) era.Neuroimaging tests on cART treated patients ...Immune cell accumulation and white matter anomaly are common features of HIV(human immunodeficiency virus)-infected patients in combination antiretroviral therapy(cART) era.Neuroimaging tests on cART treated patients displayed prominent diffuse white matter lesions.Notably,immune cell nodular lesion(NL) was a conspicuous type of pathological change in HIV/SIV(simian immunodeficiency virus) infected brain before cART.Therefore,we used SIV infected brain to investigate the distribution of those NLs in gray and white matters.We found a significant higher number of NLs in white matter than that in gray matter.However,virus infection correlated with macrophage NLs but not with microglia NLs,especially in white matter.In addition,NLs interrupted white matter integrity more severely,since even tiny nodules could disconnect nerve fibers in white matter tracts.In the gray matter with dense myelinated axons,NLs obviously encroached those fibers;in the area of few myelinated axons,small nodules well co-localized with extracellular matrix between neurons.展开更多
文摘用0、50、100、150和200 m M Na Cl溶液处理不同秋眠等级紫花苜蓿标准品种Maverick、Archer和CUF101,观察形态特征和盐害级别,测定叶片净光合速率(Pn)、细胞间隙CO2浓度(Ci)和气孔导度(Gs),分析盐胁迫对不同秋眠等级紫花苜蓿光合特性的影响.不同秋眠等级紫花苜蓿植株叶片盐害级别随品种和处理浓度不同而不同,但均随Na Cl浓度的增加和胁迫时间的延长而加大.在较低Na Cl浓度下Maverick、Archer和CUF101光合响应存在着预警阶段-恢复阶段-耗尽阶段,在高Na Cl浓度下,所有的供试品种光合响应直接进入耗尽阶段.
文摘The number of patients with chronic kidney disease re-quiring renal replacement therapy has increased world-wide. The most common replacement therapy is hemo-dialysis （HD）. Vascular access （VA） has a key role for successful treatment. Despite the advances that have taken place in the feld of the HD procedure, few things have changed with regards to VA in recent years. Ar-teriovenous fstula （AVF）, polytetrafuoroethylene graft and the cuffed double lumen silicone catheter are the most common used for VA. In the long term, a number of complications may present and more than one VA is needed during the HD life. The most common com-plications for all of VA types are thrombosis, bleeding and infection, the most common cause of morbidity in these patients. It has been estimated that VA dysfunc-tion is responsible for 20% of all hospitalizations. The annual cost of placing and looking after dialysis VA in the United States exceeds 1 billion dollars per year. A good functional access is also vital in order to deliver adequate HD therapy. It seems that the native AVF that Brescia and Cimino described in 1966 still remains the frst choice for VA. The native forearm AVFs have the longest survival and require the fewest interventions. For this reason, the forearm AVF is the frst choice, fol-lowed by the upper-arm AVF, the arteriovenous graft and the cuffed central venous catheter is the final choice. In conclusion, VA remains the most importantissue for patients on HD and despite the technical im-provements, a number of problems and complications have to be resolved.
基金“Diseno y optimización de dispositivos de drenaje para pacientes con glaucoma mediante el uso de modelos computacionales de ojos"founded by Cienciactiva,CONCYTEC,under the contract number N°008-2016-FONDECYTfinancial support from the Peruvian Government
文摘The mechanical behavior of advanced composites can be modeled mathematically through unknown variables and Shear Strain Thickness Functions(SSTFs). Such SSTFs can be of polynomial or non-polynomial nature and some parameters of non-polynomial SSTFs can be optimized to get optimal results. In this paper, these parameters are called ‘‘r" and ‘‘s" and they are the argument of the trigonometric SSTFs introduced within the Carrera Unified Formulation(CUF). The Equivalent Single Layer(ESL) governing equations are obtained by employing the Principle of Virtual Displacement(PVD) and are solved using Navier method solution. Furthermore, trigonometric expansion with Murakami theory was implemented in order to reproduce the Zig-Zag effects which are important for multilayer structures. Several combinations of optimization parameters are evaluated and selected by different criteria of average error. Results of the present unified trigonometrical theory with CUF bases confirm that it is possible to improve the stress and displacement results through the thickness distribution of models with reduced unknown variables. Since the idea is to find a theory with reduced numbers of unknowns, the present method appears to be an appropriate technique to select a simple model. However these optimization parameters depend on the plate geometry and the order of expansion or unknown variables. So, the topic deserves further research.
文摘Panel flutter phenomena can be strongly affected by thermal loads,and so a refined aeroelastic model is presented.Higher-order shell theories are used as structural models.The aerodynamic forces are described using the Piston theory.The temperature is considered uniform over the thickness of the panel.The aero-thermo-elastic model is derived in the framework of the Carrera unified formulation(CUF),therefore the matrices are expressed in a compact form using the″fundamental nuclei″.Composite and sandwich structures are considered and different boundary conditions are taken into account.The effects of the thermal load on the aeroelastic behavior are investigated.
文摘The buckling of thin-walled structures is presented using the 1D finite element based refined beam theory formulation that permits us to obtain N-order expansions for the three displacement fields over the section domain.These higher-order models are obtained in the framework of the Carrera unified formulation(CUF).CUF is a hierarchical formulation in which the refined models are obtained with no need for ad hoc formulations.Beam theories are obtained on the basis of Taylor-type and Lagrange polynomial expansions.Assessments of these theories have been carried out by their applications to studies related to the buckling of various beam structures,like the beams with square cross section,I-section,thin rectangular cross section,and annular beams.The results obtained match very well with those from commercial finite element softwares with a significantly less computational cost.Further,various types of modes like the bending modes,axial modes,torsional modes,and circumferential shell-type modes are observed.
基金supported by R01 NS063878,R01 NS077873 and P30 MH062261(to H.X.and H.S.F.)。
文摘Immune cell accumulation and white matter anomaly are common features of HIV(human immunodeficiency virus)-infected patients in combination antiretroviral therapy(cART) era.Neuroimaging tests on cART treated patients displayed prominent diffuse white matter lesions.Notably,immune cell nodular lesion(NL) was a conspicuous type of pathological change in HIV/SIV(simian immunodeficiency virus) infected brain before cART.Therefore,we used SIV infected brain to investigate the distribution of those NLs in gray and white matters.We found a significant higher number of NLs in white matter than that in gray matter.However,virus infection correlated with macrophage NLs but not with microglia NLs,especially in white matter.In addition,NLs interrupted white matter integrity more severely,since even tiny nodules could disconnect nerve fibers in white matter tracts.In the gray matter with dense myelinated axons,NLs obviously encroached those fibers;in the area of few myelinated axons,small nodules well co-localized with extracellular matrix between neurons.
