To build a community of scientific innovation,serve the country’s goals of carbon peak and carbon neutrality,promote application of scientific research outcomes in the Guangdong-Hong Kong-Macao Greater Bay Area(GBA),...To build a community of scientific innovation,serve the country’s goals of carbon peak and carbon neutrality,promote application of scientific research outcomes in the Guangdong-Hong Kong-Macao Greater Bay Area(GBA),and accelerate the formation of new quality productive forces in the green energy industry,the Yangjiang Offshore Wind Power Laboratory and the GBA Institute of Industry and Talent(GBAIIT)recently signed a strategic cooperation agreement.展开更多
DNA polymerases are an essential class of enzymes or molecular motors that catalyze processive DNA syntheses during DNA replications. A critical issue for DNA polymerases is their molecular mechanism of processive DNA...DNA polymerases are an essential class of enzymes or molecular motors that catalyze processive DNA syntheses during DNA replications. A critical issue for DNA polymerases is their molecular mechanism of processive DNA replication. We have proposed a model for chemomechanical coupling of DNA polymerases before, based on which the predicted results have been provided about the dependence of DNA replication velocity upon the external force on Klenow fragment of DNA polymerase I. Here, we performed single molecule measurements of the replication velocity of Klenow fragment under the external force by using magnetic tweezers. The single molecule data verified quantitatively the previous theoretical predictions, which is critical to the chemomechanical coupling mechanism of DNA polymerases. A prominent characteristic for the Klenow fragment is that the replication velocity is independent of the assisting force whereas the velocity increases largely with the increase of the resisting force,attains the maximum velocity at about 3.8 pN and then decreases with the further increase of the resisting force.展开更多
In classic mechanics, the force is the interaction of matter, and it is also the basic reason for accelerated motion of objects. In general relativity, the force is no longer the interaction of objects, but the result...In classic mechanics, the force is the interaction of matter, and it is also the basic reason for accelerated motion of objects. In general relativity, the force is no longer the interaction of objects, but the result of curvature of space and time. In this paper, the significance of acceleration is elaborated according to Axioms 1 and 3. Being different from Axiom 2 in which the acceleration force of the continuum is given by the ratio of variables, the accelerated motion in Axiom 1 is carried out in units superimposed because there is only one space or time independently where space-time bending is meaningless. The accelerated motion in Axiom 3 can be considered to be described by using the equation of the linear and curvilinear process of the continuum extending to infinitely distance. Further, this linear and curvilinear process of the continuum is only a quantitative continuum in essence and thus an accelerated motion transmitting from finite to infinite quantities must be jumping by an infinitely great accelerating force.展开更多
Variable acceleration linear motion is an important motion model in senior high school. This paper analyzes five common variable acceleration linear motion models in senior high school physics, and summarizes the crit...Variable acceleration linear motion is an important motion model in senior high school. This paper analyzes five common variable acceleration linear motion models in senior high school physics, and summarizes the critical state in the process of object motion, as well as solutions to common problems in the models.展开更多
文摘To build a community of scientific innovation,serve the country’s goals of carbon peak and carbon neutrality,promote application of scientific research outcomes in the Guangdong-Hong Kong-Macao Greater Bay Area(GBA),and accelerate the formation of new quality productive forces in the green energy industry,the Yangjiang Offshore Wind Power Laboratory and the GBA Institute of Industry and Talent(GBAIIT)recently signed a strategic cooperation agreement.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 11674381, 21991133, 11774407, 11874415, 1187441431770812)+3 种基金the Key Research Program on Frontier Science (Grant No. QYZDB-SSWSLH045)the National Key Research and Development Program of China (Grant No. 2016YFA0301500)the CAS Strategic Priority Research Program (Grant No. XDB37010100)the National Laboratory of Biomacromolecules (Grant No. 2020kf02)。
文摘DNA polymerases are an essential class of enzymes or molecular motors that catalyze processive DNA syntheses during DNA replications. A critical issue for DNA polymerases is their molecular mechanism of processive DNA replication. We have proposed a model for chemomechanical coupling of DNA polymerases before, based on which the predicted results have been provided about the dependence of DNA replication velocity upon the external force on Klenow fragment of DNA polymerase I. Here, we performed single molecule measurements of the replication velocity of Klenow fragment under the external force by using magnetic tweezers. The single molecule data verified quantitatively the previous theoretical predictions, which is critical to the chemomechanical coupling mechanism of DNA polymerases. A prominent characteristic for the Klenow fragment is that the replication velocity is independent of the assisting force whereas the velocity increases largely with the increase of the resisting force,attains the maximum velocity at about 3.8 pN and then decreases with the further increase of the resisting force.
文摘In classic mechanics, the force is the interaction of matter, and it is also the basic reason for accelerated motion of objects. In general relativity, the force is no longer the interaction of objects, but the result of curvature of space and time. In this paper, the significance of acceleration is elaborated according to Axioms 1 and 3. Being different from Axiom 2 in which the acceleration force of the continuum is given by the ratio of variables, the accelerated motion in Axiom 1 is carried out in units superimposed because there is only one space or time independently where space-time bending is meaningless. The accelerated motion in Axiom 3 can be considered to be described by using the equation of the linear and curvilinear process of the continuum extending to infinitely distance. Further, this linear and curvilinear process of the continuum is only a quantitative continuum in essence and thus an accelerated motion transmitting from finite to infinite quantities must be jumping by an infinitely great accelerating force.
文摘Variable acceleration linear motion is an important motion model in senior high school. This paper analyzes five common variable acceleration linear motion models in senior high school physics, and summarizes the critical state in the process of object motion, as well as solutions to common problems in the models.
