In order to study selection indices for improving rice grain yield, a cross was made between an Iranian traditional rice (Oryza sativa L.) variety, Tarommahalli and an improved indica rice variety, Khazar in 2006. The...In order to study selection indices for improving rice grain yield, a cross was made between an Iranian traditional rice (Oryza sativa L.) variety, Tarommahalli and an improved indica rice variety, Khazar in 2006. The traits of the parents (30 plants), F1 (30 plants) and F2 generations (492 individuals) were evaluated at the Rice Research Institute of Iran (RRII) during 2007. Heritabilities of the number of panicles per plant, plant height, days to heading and panicle exsertion were greater than that of grain yield. The selection indices were developed using the results of multivariate analysis. To evaluate selection strategies to maximize grain yield, 14 selection indices were calculated based on two methods (optimum and base) and combinations of 12 traits with various economic weights. Results of selection indices showed that selection for grain weight, number of panicles per plant and panicle length by using their phenotypic and/or genotypic direct effects (path coefficient) as economic weights should serve as an effective selection criterion for using either the optimum or base index.展开更多
A chemically modified carbon paste electrode (CPE), consisting of 2,2'-[ (1E)- (1,2- phenylenebis (azanylylidene)] bis (methanylylidene)]bis (benzene-1,4-diol) (PBD) and multiwalled carbon nano-tubes (CNTs), was u...A chemically modified carbon paste electrode (CPE), consisting of 2,2'-[ (1E)- (1,2- phenylenebis (azanylylidene)] bis (methanylylidene)]bis (benzene-1,4-diol) (PBD) and multiwalled carbon nano-tubes (CNTs), was used to study the electrocatalytic oxidation of dopamine using cyclic voltamme-try, chronoamperometry, and differential pulse voltammetry (DPV). First, the electrochemical be-havior of the modified electrode was investigated in buffer solution. Then the diffusion coefficient, electrocatalytic rate constant, and electron-transfer coefficient for dopamine oxidation at the sur-face of the PBD-modified CNT paste electrode were determined using electrochemical approaches. It was found that under optimum conditions (pH = 7.0), the oxidation of dopamine at the surface of such an electrode occurred at about 200 mV, lower than that of an unmodified CPE. DPV of dopa-mine at the modified electrode exhibited two linear dynamic ranges, with a detection limit of 1.0 μmol/L. Finally, DPV was used successfully for the simultaneous determination of dopamine, uric acid, and folic acid at the modified electrode, and detection limits of 1.0, 1.2, and 2.7 μmol/L were obtained for dopamine, uric acid, and folic acid, respectively. This method was also used for the determination of dopamine in a pharmaceutical preparation using the standard addition method.展开更多
There is a steep increase in data encoded as symmetric positive definite(SPD)matrix in the past decade.The set of SPD matrices forms a Riemannian manifold that constitutes a half convex cone in the vector space of mat...There is a steep increase in data encoded as symmetric positive definite(SPD)matrix in the past decade.The set of SPD matrices forms a Riemannian manifold that constitutes a half convex cone in the vector space of matrices,which we sometimes call SPD manifold.One of the fundamental problems in the application of SPD manifold is to find the nearest neighbor of a queried SPD matrix.Hashing is a popular method that can be used for the nearest neighbor search.However,hashing cannot be directly applied to SPD manifold due to its non-Euclidean intrinsic geometry.Inspired by the idea of kernel trick,a new hashing scheme for SPD manifold by random projection and quantization in expanded data space is proposed in this paper.Experimental results in large scale nearduplicate image detection show the effectiveness and efficiency of the proposed method.展开更多
Repair and maintenance costs are the most important factors affecting decision making about substituting agricultural machineries. This decision is made based on the economic life （time） of machineries. In this rese...Repair and maintenance costs are the most important factors affecting decision making about substituting agricultural machineries. This decision is made based on the economic life （time） of machineries. In this research, condition monitoring of MF285 and MF399 tractors was performed using engine oil analysis to find the optimum life time of tractor substitution in comparison with the breakdown maintenance method in Iran. All recorded information about fixed and variable costs were selected as data base and analyzed. Data were divided （classified） based on period of annual working time. Using power regression analysis led to find mathematical models for the optimum time life definition. Cumulative working time （X） was selected as independent and cumulative costs based on definite percent of initial price （Y） was considered as dependent variable and a power law equation was found to express the costs of both MF399 and MF285 tractors as a function of working time. Results showed that in CM method, average of economic life was 13 and 11 years for MF399 and MF285, respectively. It was also found that in BM method, economic life wasl0 and 8.5 years for MF399 and MF285, respectively.展开更多
Background:Traumatic brain injury,one of the leading causes of death in adults under 40 years of age in the world,is frequently caused by mechanical shock,resulting in diffuse neuronal damage and long-term cognitive d...Background:Traumatic brain injury,one of the leading causes of death in adults under 40 years of age in the world,is frequently caused by mechanical shock,resulting in diffuse neuronal damage and long-term cognitive dysfunction.Many existing TBI animal models revival with expensive equipment or special room are needed or the processes of operations are complex and not easy to be widely used.Therefore,a simpler TBI model needs to be designed.Methods:Our TBI model is an innovation of the modeling method through air guns shutting rubber bullets.A core facet is the application of our designed rubber bullet impact device.It could focus the hitting power to the fixed site of the brain,thus triggering a mild closed head injury.Moreover,the degree of damage can be adjusted by the times of shots.Results:Our model induced blood-brain barrier leakage and diffused neuronal damage.Besides,it led to an increased level of Tau phosphorylation and resulted in cognitive dysfunction within several weeks post-injury.Conclusion:Our TBI model is not only simple and time-saving but also can simulate mild brain injuries in clinical.It is suitable for exploring pathobiological mechanisms as well as a screening of potential therapies for TBI.展开更多
文摘In order to study selection indices for improving rice grain yield, a cross was made between an Iranian traditional rice (Oryza sativa L.) variety, Tarommahalli and an improved indica rice variety, Khazar in 2006. The traits of the parents (30 plants), F1 (30 plants) and F2 generations (492 individuals) were evaluated at the Rice Research Institute of Iran (RRII) during 2007. Heritabilities of the number of panicles per plant, plant height, days to heading and panicle exsertion were greater than that of grain yield. The selection indices were developed using the results of multivariate analysis. To evaluate selection strategies to maximize grain yield, 14 selection indices were calculated based on two methods (optimum and base) and combinations of 12 traits with various economic weights. Results of selection indices showed that selection for grain weight, number of panicles per plant and panicle length by using their phenotypic and/or genotypic direct effects (path coefficient) as economic weights should serve as an effective selection criterion for using either the optimum or base index.
基金the Yazd University Research Council, the IUT Research Council and Excellence in Sensors for financial support of this research.
文摘A chemically modified carbon paste electrode (CPE), consisting of 2,2'-[ (1E)- (1,2- phenylenebis (azanylylidene)] bis (methanylylidene)]bis (benzene-1,4-diol) (PBD) and multiwalled carbon nano-tubes (CNTs), was used to study the electrocatalytic oxidation of dopamine using cyclic voltamme-try, chronoamperometry, and differential pulse voltammetry (DPV). First, the electrochemical be-havior of the modified electrode was investigated in buffer solution. Then the diffusion coefficient, electrocatalytic rate constant, and electron-transfer coefficient for dopamine oxidation at the sur-face of the PBD-modified CNT paste electrode were determined using electrochemical approaches. It was found that under optimum conditions (pH = 7.0), the oxidation of dopamine at the surface of such an electrode occurred at about 200 mV, lower than that of an unmodified CPE. DPV of dopa-mine at the modified electrode exhibited two linear dynamic ranges, with a detection limit of 1.0 μmol/L. Finally, DPV was used successfully for the simultaneous determination of dopamine, uric acid, and folic acid at the modified electrode, and detection limits of 1.0, 1.2, and 2.7 μmol/L were obtained for dopamine, uric acid, and folic acid, respectively. This method was also used for the determination of dopamine in a pharmaceutical preparation using the standard addition method.
文摘There is a steep increase in data encoded as symmetric positive definite(SPD)matrix in the past decade.The set of SPD matrices forms a Riemannian manifold that constitutes a half convex cone in the vector space of matrices,which we sometimes call SPD manifold.One of the fundamental problems in the application of SPD manifold is to find the nearest neighbor of a queried SPD matrix.Hashing is a popular method that can be used for the nearest neighbor search.However,hashing cannot be directly applied to SPD manifold due to its non-Euclidean intrinsic geometry.Inspired by the idea of kernel trick,a new hashing scheme for SPD manifold by random projection and quantization in expanded data space is proposed in this paper.Experimental results in large scale nearduplicate image detection show the effectiveness and efficiency of the proposed method.
文摘Repair and maintenance costs are the most important factors affecting decision making about substituting agricultural machineries. This decision is made based on the economic life （time） of machineries. In this research, condition monitoring of MF285 and MF399 tractors was performed using engine oil analysis to find the optimum life time of tractor substitution in comparison with the breakdown maintenance method in Iran. All recorded information about fixed and variable costs were selected as data base and analyzed. Data were divided （classified） based on period of annual working time. Using power regression analysis led to find mathematical models for the optimum time life definition. Cumulative working time （X） was selected as independent and cumulative costs based on definite percent of initial price （Y） was considered as dependent variable and a power law equation was found to express the costs of both MF399 and MF285 tractors as a function of working time. Results showed that in CM method, average of economic life was 13 and 11 years for MF399 and MF285, respectively. It was also found that in BM method, economic life wasl0 and 8.5 years for MF399 and MF285, respectively.
基金This work was supported by the National Natural Science Foundation of China(grant number 81671264)Guangzhou Scientific Foundation Committee(grant numbers 201704020222 and 201807010094)
文摘Background:Traumatic brain injury,one of the leading causes of death in adults under 40 years of age in the world,is frequently caused by mechanical shock,resulting in diffuse neuronal damage and long-term cognitive dysfunction.Many existing TBI animal models revival with expensive equipment or special room are needed or the processes of operations are complex and not easy to be widely used.Therefore,a simpler TBI model needs to be designed.Methods:Our TBI model is an innovation of the modeling method through air guns shutting rubber bullets.A core facet is the application of our designed rubber bullet impact device.It could focus the hitting power to the fixed site of the brain,thus triggering a mild closed head injury.Moreover,the degree of damage can be adjusted by the times of shots.Results:Our model induced blood-brain barrier leakage and diffused neuronal damage.Besides,it led to an increased level of Tau phosphorylation and resulted in cognitive dysfunction within several weeks post-injury.Conclusion:Our TBI model is not only simple and time-saving but also can simulate mild brain injuries in clinical.It is suitable for exploring pathobiological mechanisms as well as a screening of potential therapies for TBI.
