Given that glyphosate weed control is an effective strategy to reduce costs and improve economic outcomes of agricultural production in China,the development of glyphosate-resistant cotton holds great promise.Using an...Given that glyphosate weed control is an effective strategy to reduce costs and improve economic outcomes of agricultural production in China,the development of glyphosate-resistant cotton holds great promise.Using an Agrobacterium-mediated transformation method,a new G2-aroA gene that encodes 5-enolpyruvylshikimate-3-phosphate synthase（EPSPS）was transformed into cotton cultivar K312.The transgenic cotton plants were regenerated from a callus tissue culture via kanamycin selection.Ten regenerated cotton plants were obtained and allowed to flower normally to produce fruit.The results from polymerase chain reaction（PCR）and Southern and Western blot analyses indicated that the target gene was integrated into the cotton chromosome and was expressed effectively at the protein level.The glyphosate tolerance analysis showed that the transgenic cotton had a high resistance to glyphosate.Further,even cotton treated with 45.0 mmol L^–1 of glyphosate was able to slowly grow,bloom and seed.The transgenic cotton may be used for cotton breeding research of glyphosate-tolerant cotton.展开更多
In order to smooth the trajectory of a robot and reduce dwell time,a transition curve is introduced between two adjacent curves in three-dimensional space.G2 continuity is guaranteed to transit smoothly.To minimize th...In order to smooth the trajectory of a robot and reduce dwell time,a transition curve is introduced between two adjacent curves in three-dimensional space.G2 continuity is guaranteed to transit smoothly.To minimize the amount of calculation,cubic and quartic Bezier curves are both analyzed.Furthermore,the contour curve is characterized by a transition parameter which defines the distance to the corner of the deviation.How to define the transition points for different curves is presented.A general move command interface is defined for receiving the curve limitations and transition parameters.Then,how to calculate the control points of the cubic and quartic Bezier curves is analyzed and given.Different situations are discussed separately,including transition between two lines,transition between a line and a circle,and transition between two circles.Finally,the experiments are carried out on a six degree of freedom(DOF) industrial robot to validate the proposed method.Results of single transition and multiple transitions are presented.The trajectories in the joint space are also analyzed.The results indicate that the method achieves G2 continuity within the transition constraint and has good efficiency and adaptability.展开更多
基金supported by the Genetically Modified Major Projects, China (2012ZX08011-003 and 2014ZX08011-004B)
文摘Given that glyphosate weed control is an effective strategy to reduce costs and improve economic outcomes of agricultural production in China,the development of glyphosate-resistant cotton holds great promise.Using an Agrobacterium-mediated transformation method,a new G2-aroA gene that encodes 5-enolpyruvylshikimate-3-phosphate synthase（EPSPS）was transformed into cotton cultivar K312.The transgenic cotton plants were regenerated from a callus tissue culture via kanamycin selection.Ten regenerated cotton plants were obtained and allowed to flower normally to produce fruit.The results from polymerase chain reaction（PCR）and Southern and Western blot analyses indicated that the target gene was integrated into the cotton chromosome and was expressed effectively at the protein level.The glyphosate tolerance analysis showed that the transgenic cotton had a high resistance to glyphosate.Further,even cotton treated with 45.0 mmol L^–1 of glyphosate was able to slowly grow,bloom and seed.The transgenic cotton may be used for cotton breeding research of glyphosate-tolerant cotton.
基金Supported by the National Natural Science Foundation of China(No.61573358)Research and Development of Large Multi-function Demolition Equipment in Disaster Site(No.2015BAK06B00)
文摘In order to smooth the trajectory of a robot and reduce dwell time,a transition curve is introduced between two adjacent curves in three-dimensional space.G2 continuity is guaranteed to transit smoothly.To minimize the amount of calculation,cubic and quartic Bezier curves are both analyzed.Furthermore,the contour curve is characterized by a transition parameter which defines the distance to the corner of the deviation.How to define the transition points for different curves is presented.A general move command interface is defined for receiving the curve limitations and transition parameters.Then,how to calculate the control points of the cubic and quartic Bezier curves is analyzed and given.Different situations are discussed separately,including transition between two lines,transition between a line and a circle,and transition between two circles.Finally,the experiments are carried out on a six degree of freedom(DOF) industrial robot to validate the proposed method.Results of single transition and multiple transitions are presented.The trajectories in the joint space are also analyzed.The results indicate that the method achieves G2 continuity within the transition constraint and has good efficiency and adaptability.
