The heavy ions with high linear energy transfer and high relative biological effectiveness are much more deleterious on the male germ cells, ones of the most radiosensitive cells of the body,than low-LET ionizing radi...The heavy ions with high linear energy transfer and high relative biological effectiveness are much more deleterious on the male germ cells, ones of the most radiosensitive cells of the body,than low-LET ionizing radiation such as X-ray or gamma-ray. The effects of low-dose heavy ion irradiation on male germ cell adaptation and genetics and the possible mechanism of this adaptation are summarized in our laboratory. Our results showed that the heavy ion irradiation significantly increased the frequencies of chromosomal aberrations in spermatogonia and spermato-cytes of mice, the low dose heavy ion irradiation could induce significant adaptative response on mouse testes and human sperm, and pre-exposure of mouse testes with low-dose heavy ion can markedly alleviate damage effects in-duced by subsequent high-dose irradiation. The increase of SOD activity and decrease of lipid peroxidation levels induced by low-dose ionizing radiation may be involved in this adaptative response mechanism. These studies may provide useful theoretical and clinical bases for radioprotection of reproductive potential and assessment of genetic risks for human exposed to heavy ions in radiotherapy and in outer space environment.展开更多
Heavy ion irradiated polymers can be chemically etched to form track membrane with pores in the micro and sub-micro ranges. The basic proccsses of track membrane production are irradiation of thin polymer films throug...Heavy ion irradiated polymers can be chemically etched to form track membrane with pores in the micro and sub-micro ranges. The basic proccsses of track membrane production are irradiation of thin polymer films through heavy ions followcd by chemical ctching. The track mcmbrane parameters such as pore size and shape, pore density, aspect ratio etc. depend on many factors such as material properties, irradiation conditions (ions, ion energy and fluence etc.) and etching conditions (etchant concentration, etching temperature etc.), as well as the treatmcnts of the material before or during chemical etching. In this work the Xe-ion irradiated PET fihns were chcmically etchcd and the pore growth processes were followed from which the etching parameters were evaluated and analyzed with respect to etchant concentration and applied voltages.展开更多
文摘The heavy ions with high linear energy transfer and high relative biological effectiveness are much more deleterious on the male germ cells, ones of the most radiosensitive cells of the body,than low-LET ionizing radiation such as X-ray or gamma-ray. The effects of low-dose heavy ion irradiation on male germ cell adaptation and genetics and the possible mechanism of this adaptation are summarized in our laboratory. Our results showed that the heavy ion irradiation significantly increased the frequencies of chromosomal aberrations in spermatogonia and spermato-cytes of mice, the low dose heavy ion irradiation could induce significant adaptative response on mouse testes and human sperm, and pre-exposure of mouse testes with low-dose heavy ion can markedly alleviate damage effects in-duced by subsequent high-dose irradiation. The increase of SOD activity and decrease of lipid peroxidation levels induced by low-dose ionizing radiation may be involved in this adaptative response mechanism. These studies may provide useful theoretical and clinical bases for radioprotection of reproductive potential and assessment of genetic risks for human exposed to heavy ions in radiotherapy and in outer space environment.
文摘Heavy ion irradiated polymers can be chemically etched to form track membrane with pores in the micro and sub-micro ranges. The basic proccsses of track membrane production are irradiation of thin polymer films through heavy ions followcd by chemical ctching. The track mcmbrane parameters such as pore size and shape, pore density, aspect ratio etc. depend on many factors such as material properties, irradiation conditions (ions, ion energy and fluence etc.) and etching conditions (etchant concentration, etching temperature etc.), as well as the treatmcnts of the material before or during chemical etching. In this work the Xe-ion irradiated PET fihns were chcmically etchcd and the pore growth processes were followed from which the etching parameters were evaluated and analyzed with respect to etchant concentration and applied voltages.
