分类： 天文学 >> 天文学 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： The near-infrared imaging channel constitutes a crucial component of the multichannel high-resolution imaging system of the New Vacuum Solar Telescope (NVST). We have successfully achieved high-resolution, narrowband imaging of the chromosphere using He i 10830 Å triplet within this channel, which significantly enhances the imaging observation capabilities of NVST. This paper provides a concise overview of the optical system associated with the near-infrared imaging channel, detailing data processing procedures and presenting several observed images. Leveraging a high-resolution image reconstruction algorithm, we were able to generate a narrowband image near the diffraction limit at 10830 Å with a temporal resolution of less than 10 s.
分类： 生物学 >> 生物物理学 >> 生物力学与生物流变学 提交时间： 2016-05-12
Zhang, Zhenya
Li, Kaiming
Cai, Zeyuan
Fang, Yu
An, Lili
Hu, Zhishang
Hang, Haiying
Cai, Zeyuan
Hu, Zhishang
摘要： Rad9, Rad1 and Hus1 are essential genes conserved from yeast to humans. They form a heterotrimer complex (9-1-1 complex) that participates in the cell cycle checkpoint activation and DNA damage repair in eukaryotic cells. Rad9, Rad1 and Hus1 deficient cells are hypersensitive to ionizing radiation and mouse cells deleted for anyone of the three genes are highly sensitive to the killing by gamma rays. We propose that ionizing radiation-induced transcription of these genes is a mechanism by which cells respond to radiation-induced damage. In this study we used quantitative real-time RT-PCR(qPCR) to analyze the mRNA levels of Rad9, Rad1 and Hus1 in various tissues isolated from mice that were either mock irradiated or exposed to 10 Gy gamma radiation. Our results indicated that the mRNA levels of Rad9, Rad1 and Hus1 genes were very different among these tissues, and we found high natural levels of mRNA in the spleen, lung, ovary and testis of mice before exposure to radiation. The mRNA levels of the three genes were well correlated across these tissues, being high, medium or low in each of the tissues simultaneously. The mRNA levels of the three genes were analyzed at 2, 6, 12, 24 and 48 h after irradiation. In most tissues Rad9 was strongly induced at 2 and 12 h time points and Hus1 was strongly induced at 2, 12 and 48 h time points, but Rad1 was minimally induced in most of the tissues with the exception of slightly higher levels in the heart and lung tissues at the 48 h time point. These results suggest that the regulation mechanisms for the mRNA levels of the three genes in response to ionizing radiation are complex and not well orchestrated. We also detected the induction of Rad9 and Hus1 proteins in the heart and liver of the animals after irradiation, and found that Rad9 protein levels were highly induced in both the heart and liver, while the Hus1 protein levels were significantly induced only in the liver, suggesting that Rad9 and Hus1 protein levels are not regulated in a coordinated manner in response to irradiation. We then went on to measure the mRNA levels of the three genes and the Rad9 and Hus1 protein levels in the mouse liver cell line (NCTC 1469) in response to irradiation in vitro. All three genes in the cultured cells were minimally induced at mRNA level, obviously different from the highly dynamic induction in liver. Rad9 and Hus1 were significantly induced at the protein level, but the induced Rad9 protein levels were higher than the Hus1 levels. Taken together, the good correlation of the mRNA levels of Rad9, Hus1 and Rad1 genes across different tissues isolated from the animals that were mock irradiated and the lack of correlation in mRNA as well as protein levels after irradiation suggest that the 9-1-1 complex has evolved to play various physiological roles in tissues rather than dealing with high doses of gamma radiation or other genotoxic agents. (C) 2015 by Radiation Research Society
分类： 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间： 2017-05-02
Li, ZG [Li, Zhong-guo][ 1 ]
Liang, LY [Liang, Lingyan][ 2 ]
Cao, HT [Cao, Hongtao][ 2 ]
Xiao, ZG [Xiao, Zhengguo][ 1 ]
Wu, XZ [Wu, Xingzhi][ 1 ]
Fang, Y [Fang, Yu][ 3 ]
Yang, JY [Yang, Junyi][ 3 ]
Wei, TH [Wei, Tai-Huei][ 1 ]
Song, YL [Song, Ying-lin][ 1,3 ]
摘要： We studied the carrier dynamics in a series of SnOx thin films using femtosecond transient absorption (TA) spectroscopy. The observed carrier relaxation was found to be strongly dependent on thin film stoichiometry. The TA spectra corresponding to free carriers, trapped carriers, and state filling were observed in the picosecond time region for SnO2, SnOx, and SnO film, respectively. The TA decay kinetics of all films were best fit with a tri-exponential decay model with fast (1 ps), medium ( 10 ps), and slow (ns) components. Our results revealed the carrier relaxation and recombination processes in SnOx thin films, identifying the critical role of stoichiometry in photo-induced phenomena.
点击量
通过
点击量
下载量
评论
待评议
