Topological current of point defects and its bifurcation

From the topological properties of a three dimensional vector order parameter, the topological current of point defects is obtained. One shows that the charge of point defects is determined by Hopf indices and Brouwer degrees. The evolution of point defects is also studied. One concludes that there exist crucial cases of branch processes in the evolution of point defects when the Jacobian $D(\frac \phi x)=0$.Comment: revtex,14 pages,no figur

Phase-matched locally chiral light for global control of chiral light-matter interaction

Locally chiral light is an emerging tool for probing and controlling molecular chirality. It can generate large and freely adjustable enantioselectivities in purely electric-dipole effects, offering its major advantages over traditional chiral light. However, the existing types of locally chiral light are phase-mismatched, and thus the global efficiencies are greatly reduced compared with the maximum single-point efficiencies or even vanish. Here, we propose a scheme to generate phase-matched locally chiral light. To confirm this advantage, we numerically show the robust highly efficient global control of enantiospecific electronic state transfer of methyloxirane at nanoseconds. Our work potentially constitutes the starting point for developing more efficient chiroptical techniques for the studies of chiral molecules.Comment: 5 pages, 3figures, 1 supplment documen

Community Built Environment and Multilevel Social Determinants of Obesity: Evidence from China Health and Nutrition Survey

The prevalence of overweight and obesity is highest in wealthy countries like the United States, but is rapidly increasing in less developed countries. From 1992 to 2002, China had an increase from 14.6% to 21.8% in overweight and obesity. Social determinants of obesity in developing countries remain poorly understood. Further, these associations may vary by community built environment (BE) of developing countries

Intelligent high-altitude power inspection vision module based on KendryteK210 microcontroller

Now our country has a huge electric power system, it needs a complex electric power transmission network to support its normal operation. With the development of unmanned aerial vehicle platform and microprocessor technology in recent years, the unmanned aerial vehicle inspection platform based on microprocessor is an important development direction of power transmission network maintenance. Based on this background, this paper designs an intelligent high-altitude line inspection vision module based on KendryteK210 microcontroller. The module can be used as a UAV load to carry out efficient power line patrol work, and wireless communication is carried out by ESP8285Wi-Fi. First of all, the inspection vision module uses OV2640 visible light camera to complete the target image data acquisition. Then, in the process of data processing, the least square method and Theil-Sen regression algorithm are combined to get the target line object, so as to get the slope and length of the line object and other parameters. Finally, the target in the image was identifi ed based on the yolov2 neural network model, and then the fl ight path instruction was provided for the UAV platform