We present 145 times of light maximum for high amplitude δ Scuti star BO Lyn based on several sky surveys(CRTS,DASCH,NSVS,OMC and Super WASP)and our photometric observations.Combining with the data in literature,a ...We present 145 times of light maximum for high amplitude δ Scuti star BO Lyn based on several sky surveys(CRTS,DASCH,NSVS,OMC and Super WASP)and our photometric observations.Combining with the data in literature,a total of 179 times of light maximum are used to analyze the O-C diagram of BO Lyn.We find that it can be described by an upward parabolic component and a periodic variation with a period of 34.5±0.1 yr.The latter could be caused by the light travel time effect as a result of an additional companion orbiting in a highly elliptical orbit(e=0.64±0.03).Our study indicates that the companion’s luminosity cannot be ignored,and it should be a late A-type main-sequence star.The long-term period change of BO Lyn is also detected,and its value,1.52±0.26×10^(-3)d Myr^(-1),is consistent with evolutionary models.We suggest that more spectroscopic and photometric observations are needed in the future to confirm the nature of the BO Lyn system.展开更多
In the present work, a treatment technique for trigeminal neuralgia (TN) using LINAC radiosurgery is shown. The technique is based on the optimization of ten static arcs in such a way as to minimize the overlapping of...In the present work, a treatment technique for trigeminal neuralgia (TN) using LINAC radiosurgery is shown. The technique is based on the optimization of ten static arcs in such a way as to minimize the overlapping of the treatment fields with the brainstem. We will call this technique brainstem-optimized (BO). The results are compared with another technique described in the literature known as a virtual cone (VC). The comparison of dosimetry results that have been carried out essentially shows that the doses in the brainstem V12Gy-brainstem, D0.5cm<sup>3</sup>-brainstem and D0.035 cm<sup>3</sup>-brainstem are lower in the BO versus VC technique, and with the parameters V50% (whole brain) and V12Gy-cerebrum higher in BO versus VC. Our goal is to keep the dose to the brainstem as low as possible and, if possible, at most between 12 Gy and 15 Gy. The BO technique meets our purposes and is considered clinically acceptable at our institution.展开更多
基金The DASCH project at Harvard is grateful for partial support from NSF grants AST-0407380,AST0909073 and AST-1313370partly supported by the West Light Foundation of Chinese Academy of Sciences+2 种基金the National Natural Science Foundation of China(Nos.11325315 and 11573063)the Yunnan Natural Science Foundation(Nos.2013FB084,2014FB187 and 2017FA001)the Strategic Priority Research Program “The Emergence of Cosmological Structures” of the Chinese Academy of Sciences(Grant No.XDB09010202)
文摘We present 145 times of light maximum for high amplitude δ Scuti star BO Lyn based on several sky surveys(CRTS,DASCH,NSVS,OMC and Super WASP)and our photometric observations.Combining with the data in literature,a total of 179 times of light maximum are used to analyze the O-C diagram of BO Lyn.We find that it can be described by an upward parabolic component and a periodic variation with a period of 34.5±0.1 yr.The latter could be caused by the light travel time effect as a result of an additional companion orbiting in a highly elliptical orbit(e=0.64±0.03).Our study indicates that the companion’s luminosity cannot be ignored,and it should be a late A-type main-sequence star.The long-term period change of BO Lyn is also detected,and its value,1.52±0.26×10^(-3)d Myr^(-1),is consistent with evolutionary models.We suggest that more spectroscopic and photometric observations are needed in the future to confirm the nature of the BO Lyn system.
文摘In the present work, a treatment technique for trigeminal neuralgia (TN) using LINAC radiosurgery is shown. The technique is based on the optimization of ten static arcs in such a way as to minimize the overlapping of the treatment fields with the brainstem. We will call this technique brainstem-optimized (BO). The results are compared with another technique described in the literature known as a virtual cone (VC). The comparison of dosimetry results that have been carried out essentially shows that the doses in the brainstem V12Gy-brainstem, D0.5cm<sup>3</sup>-brainstem and D0.035 cm<sup>3</sup>-brainstem are lower in the BO versus VC technique, and with the parameters V50% (whole brain) and V12Gy-cerebrum higher in BO versus VC. Our goal is to keep the dose to the brainstem as low as possible and, if possible, at most between 12 Gy and 15 Gy. The BO technique meets our purposes and is considered clinically acceptable at our institution.