An acoustically actuated piezoelectric antenna is proposed for low frequency(LF)band in this paper.The proposed antenna is theoretically calculated,numerically optimized by the finite element method(FEM),and experimen...An acoustically actuated piezoelectric antenna is proposed for low frequency(LF)band in this paper.The proposed antenna is theoretically calculated,numerically optimized by the finite element method(FEM),and experimentally analyzed.The measurement results show that the near-field radiation pattern of the piezoelectric antenna is similar to that of the electric dipole antenna.The radiation efficiency of the piezoelectric antenna is 3-4 orders of magnitude higher than that of electrically small antenna(ESA),with their sizes being the same size,and the maximum transmission distance obtained experimentally is 100 cm,which can be improved by increasing the input power.In addition,the gain,directivity,and quality factor of piezoelectric antenna are also analyzed.In this paper,traditional antenna parameters are creatively used to analyze the performance of piezoelectric antenna.The research conclusions can provide reliable theoretical basis for realizing LF antenna miniaturization.展开更多
Different from conventional radiotherapy(CONV-RT),FLASH radiotherapy(FLASH-RT)delivers a single high dose at a mean dose rate40 Gy/s in milliseconds to achieve similar tumor control to CONV-RT while sparing normal tis...Different from conventional radiotherapy(CONV-RT),FLASH radiotherapy(FLASH-RT)delivers a single high dose at a mean dose rate40 Gy/s in milliseconds to achieve similar tumor control to CONV-RT while sparing normal tissues from detrimental injury.It provides an intriguing perspective in improving clinical outcomes for tumor patients as well as a novel way to enhance the differential responses between normal and tumor tissues.However,its mechanisms remain largely unclear.In this paper,we review the currently available publications on FLASH-RT and parse the probable mechanisms of three major aspects including the production of reactive oxygen species,DNA damage response,and immunoreaction.Experiments specifically designed to disclose the intrinsic difference between normal and malignant cells in response to FLASH-RT and CONV-RT are necessary to prove these hypotheses.展开更多
文摘An acoustically actuated piezoelectric antenna is proposed for low frequency(LF)band in this paper.The proposed antenna is theoretically calculated,numerically optimized by the finite element method(FEM),and experimentally analyzed.The measurement results show that the near-field radiation pattern of the piezoelectric antenna is similar to that of the electric dipole antenna.The radiation efficiency of the piezoelectric antenna is 3-4 orders of magnitude higher than that of electrically small antenna(ESA),with their sizes being the same size,and the maximum transmission distance obtained experimentally is 100 cm,which can be improved by increasing the input power.In addition,the gain,directivity,and quality factor of piezoelectric antenna are also analyzed.In this paper,traditional antenna parameters are creatively used to analyze the performance of piezoelectric antenna.The research conclusions can provide reliable theoretical basis for realizing LF antenna miniaturization.
基金This work is supported by the National Key R&D Program of China(No.2018YFC0115704)The author is very grateful to Dr.Tom K.Hei from Columbia University and Drs.Zhifang Chai,Wei Yang,Haowen Zhang,Ningang Liu,Wentao Hu,and Zengfu Shang from the School of Radiation Medicine and Protection,Soochow University,for their valuable and inspiring discussion。
文摘Different from conventional radiotherapy(CONV-RT),FLASH radiotherapy(FLASH-RT)delivers a single high dose at a mean dose rate40 Gy/s in milliseconds to achieve similar tumor control to CONV-RT while sparing normal tissues from detrimental injury.It provides an intriguing perspective in improving clinical outcomes for tumor patients as well as a novel way to enhance the differential responses between normal and tumor tissues.However,its mechanisms remain largely unclear.In this paper,we review the currently available publications on FLASH-RT and parse the probable mechanisms of three major aspects including the production of reactive oxygen species,DNA damage response,and immunoreaction.Experiments specifically designed to disclose the intrinsic difference between normal and malignant cells in response to FLASH-RT and CONV-RT are necessary to prove these hypotheses.
